149 files changed, 5842 insertions, 2251 deletions

diff --git a/CREDITS b/CREDITS
index 10c214dc95e7..832436e1dd91 100644
--- a/CREDITS
+++ b/CREDITS
@@ -966,6 +966,7 @@ N: Pekka Enberg
 E: penberg@cs.helsinki.fi
 W: http://www.cs.helsinki.fi/u/penberg/
 D: Various kernel hacks, fixes, and cleanups.
+D: Slab allocators
 S: Finland
 
 N: David Engebretsen
@@ -1939,8 +1940,8 @@ D: for Menuconfig's lxdialog.
 N: Christoph Lameter
 E: christoph@lameter.com
 D: Digiboard PC/Xe and PC/Xi, Digiboard EPCA
-D: Early protocol filter for bridging code
-D: Bug fixes
+D: NUMA support, Slab allocators, Page migration
+D: Scalability, Time subsystem
 
 N: Paul Laufer
 E: paul@laufernet.com
diff --git a/Documentation/lguest/extract b/Documentation/lguest/extract
new file mode 100644
index 000000000000..7730bb6e4b94
--- /dev/null
+++ b/Documentation/lguest/extract
@@ -0,0 +1,58 @@
+#! /bin/sh
+
+set -e
+
+PREFIX=$1
+shift
+
+trap 'rm -r $TMPDIR' 0
+TMPDIR=`mktemp -d`
+
+exec 3>/dev/null
+for f; do
+    while IFS="
+" read -r LINE; do
+        case "$LINE" in
+            *$PREFIX:[0-9]*:\**)
+                NUM=`echo "$LINE" | sed "s/.*$PREFIX:\([0-9]*\).*/\1/"`
+                if [ -f $TMPDIR/$NUM ]; then
+                    echo "$TMPDIR/$NUM already exits prior to $f"
+                    exit 1
+                fi
+                exec 3>>$TMPDIR/$NUM
+                echo $f | sed 's,\.\./,,g' > $TMPDIR/.$NUM
+                /bin/echo "$LINE" | sed -e "s/$PREFIX:[0-9]*//" -e "s/:\*/*/" >&3
+                ;;
+            *$PREFIX:[0-9]*)
+                NUM=`echo "$LINE" | sed "s/.*$PREFIX:\([0-9]*\).*/\1/"`
+                if [ -f $TMPDIR/$NUM ]; then
+                    echo "$TMPDIR/$NUM already exits prior to $f"
+                    exit 1
+                fi
+                exec 3>>$TMPDIR/$NUM
+                echo $f | sed 's,\.\./,,g' > $TMPDIR/.$NUM
+                /bin/echo "$LINE" | sed "s/$PREFIX:[0-9]*//" >&3
+                ;;
+            *:\**)
+                /bin/echo "$LINE" | sed -e "s/:\*/*/" -e "s,/\*\*/,," >&3
+                echo >&3
+                exec 3>/dev/null
+                ;;
+            *)
+                /bin/echo "$LINE" >&3
+                ;;
+        esac
+    done < $f
+    echo >&3
+    exec 3>/dev/null
+done
+
+LASTFILE=""
+for f in $TMPDIR/*; do
+    if [ "$LASTFILE" != $(cat $TMPDIR/.$(basename $f) ) ]; then
+        LASTFILE=$(cat $TMPDIR/.$(basename $f) )
+        echo "[ $LASTFILE ]"
+    fi
+    cat $f
+done
+
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index 62a8133393e1..f7918401a007 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -1,5 +1,10 @@
-/* Simple program to layout "physical" memory for new lguest guest.
- * Linked high to avoid likely physical memory.  */
+/*P:100 This is the Launcher code, a simple program which lays out the
+ * "physical" memory for the new Guest by mapping the kernel image and the
+ * virtual devices, then reads repeatedly from /dev/lguest to run the Guest.
+ *
+ * The only trick: the Makefile links it at a high address so it will be clear
+ * of the guest memory region.  It means that each Guest cannot have more than
+ * about 2.5G of memory on a normally configured Host. :*/
 #define _LARGEFILE64_SOURCE
 #define _GNU_SOURCE
 #include <stdio.h>
@@ -29,12 +34,20 @@
 #include <termios.h>
 #include <getopt.h>
 #include <zlib.h>
+/*L:110 We can ignore the 28 include files we need for this program, but I do
+ * want to draw attention to the use of kernel-style types.
+ *
+ * As Linus said, "C is a Spartan language, and so should your naming be."  I
+ * like these abbreviations and the header we need uses them, so we define them
+ * here.
+ */
 typedef unsigned long long u64;
 typedef uint32_t u32;
 typedef uint16_t u16;
 typedef uint8_t u8;
 #include "../../include/linux/lguest_launcher.h"
 #include "../../include/asm-i386/e820.h"
+/*:*/
 
 #define PAGE_PRESENT 0x7        /* Present, RW, Execute */
 #define NET_PEERNUM 1
@@ -43,33 +56,52 @@ typedef uint8_t u8;
 #define SIOCBRADDIF     0x89a2          /* add interface to bridge      */
 #endif
 
+/*L:120 verbose is both a global flag and a macro.  The C preprocessor allows
+ * this, and although I wouldn't recommend it, it works quite nicely here. */
 static bool verbose;
 #define verbose(args...) \
         do { if (verbose) printf(args); } while(0)
+/*:*/
+
+/* The pipe to send commands to the waker process */
 static int waker_fd;
+/* The top of guest physical memory. */
 static u32 top;
 
+/* This is our list of devices. */
 struct device_list
 {
+        /* Summary information about the devices in our list: ready to pass to
+         * select() to ask which need servicing.*/
         fd_set infds;
         int max_infd;
 
+        /* The descriptor page for the devices. */
         struct lguest_device_desc *descs;
+
+        /* A single linked list of devices. */
         struct device *dev;
+        /* ... And an end pointer so we can easily append new devices */
         struct device **lastdev;
 };
 
+/* The device structure describes a single device. */
 struct device
 {
+        /* The linked-list pointer. */
         struct device *next;
+        /* The descriptor for this device, as mapped into the Guest. */
         struct lguest_device_desc *desc;
+        /* The memory page(s) of this device, if any.  Also mapped in Guest. */
         void *mem;
 
-        /* Watch this fd if handle_input non-NULL. */
+        /* If handle_input is set, it wants to be called when this file
+         * descriptor is ready. */
         int fd;
         bool (*handle_input)(int fd, struct device *me);
 
-        /* Watch DMA to this key if handle_input non-NULL. */
+        /* If handle_output is set, it wants to be called when the Guest sends
+         * DMA to this key. */
         unsigned long watch_key;
         u32 (*handle_output)(int fd, const struct iovec *iov,
                              unsigned int num, struct device *me);
@@ -78,6 +110,11 @@ struct device
         void *priv;
 };
 
+/*L:130
+ * Loading the Kernel.
+ *
+ * We start with couple of simple helper routines.  open_or_die() avoids
+ * error-checking code cluttering the callers: */
 static int open_or_die(const char *name, int flags)
 {
         int fd = open(name, flags);
@@ -86,26 +123,38 @@ static int open_or_die(const char *name, int flags)
         return fd;
 }
 
+/* map_zeroed_pages() takes a (page-aligned) address and a number of pages. */
 static void *map_zeroed_pages(unsigned long addr, unsigned int num)
 {
+        /* We cache the /dev/zero file-descriptor so we only open it once. */
         static int fd = -1;
 
         if (fd == -1)
                 fd = open_or_die("/dev/zero", O_RDONLY);
 
+        /* We use a private mapping (ie. if we write to the page, it will be
+         * copied), and obviously we insist that it be mapped where we ask. */
         if (mmap((void *)addr, getpagesize() * num,
                  PROT_READ|PROT_WRITE|PROT_EXEC, MAP_FIXED|MAP_PRIVATE, fd, 0)
             != (void *)addr)
                 err(1, "Mmaping %u pages of /dev/zero @%p", num, (void *)addr);
+
+        /* Returning the address is just a courtesy: can simplify callers. */
         return (void *)addr;
 }
 
-/* Find magic string marking entry point, return entry point. */
+/* To find out where to start we look for the magic Guest string, which marks
+ * the code we see in lguest_asm.S.  This is a hack which we are currently
+ * plotting to replace with the normal Linux entry point. */
 static unsigned long entry_point(void *start, void *end,
                                  unsigned long page_offset)
 {
         void *p;
 
+        /* The scan gives us the physical starting address.  We want the
+         * virtual address in this case, and fortunately, we already figured
+         * out the physical-virtual difference and passed it here in
+         * "page_offset". */
         for (p = start; p < end; p++)
                 if (memcmp(p, "GenuineLguest", strlen("GenuineLguest")) == 0)
                         return (long)p + strlen("GenuineLguest") + page_offset;
@@ -113,7 +162,17 @@ static unsigned long entry_point(void *start, void *end,
         err(1, "Is this image a genuine lguest?");
 }
 
-/* Returns the entry point */
+/* This routine takes an open vmlinux image, which is in ELF, and maps it into
+ * the Guest memory.  ELF = Embedded Linking Format, which is the format used
+ * by all modern binaries on Linux including the kernel.
+ *
+ * The ELF headers give *two* addresses: a physical address, and a virtual
+ * address.  The Guest kernel expects to be placed in memory at the physical
+ * address, and the page tables set up so it will correspond to that virtual
+ * address.  We return the difference between the virtual and physical
+ * addresses in the "page_offset" pointer.
+ *
+ * We return the starting address. */
 static unsigned long map_elf(int elf_fd, const Elf32_Ehdr *ehdr,
                              unsigned long *page_offset)
 {
@@ -122,40 +181,61 @@ static unsigned long map_elf(int elf_fd, const Elf32_Ehdr *ehdr,
         unsigned int i;
         unsigned long start = -1UL, end = 0;
 
-        /* Sanity checks. */
+        /* Sanity checks on the main ELF header: an x86 executable with a
+         * reasonable number of correctly-sized program headers. */
         if (ehdr->e_type != ET_EXEC
             || ehdr->e_machine != EM_386
             || ehdr->e_phentsize != sizeof(Elf32_Phdr)
             || ehdr->e_phnum < 1 || ehdr->e_phnum > 65536U/sizeof(Elf32_Phdr))
                 errx(1, "Malformed elf header");
 
+        /* An ELF executable contains an ELF header and a number of "program"
+         * headers which indicate which parts ("segments") of the program to
+         * load where. */
+
+        /* We read in all the program headers at once: */
         if (lseek(elf_fd, ehdr->e_phoff, SEEK_SET) < 0)
                 err(1, "Seeking to program headers");
         if (read(elf_fd, phdr, sizeof(phdr)) != sizeof(phdr))
                 err(1, "Reading program headers");
 
+        /* We don't know page_offset yet. */
         *page_offset = 0;
-        /* We map the loadable segments at virtual addresses corresponding
-         * to their physical addresses (our virtual == guest physical). */
+
+        /* Try all the headers: there are usually only three.  A read-only one,
+         * a read-write one, and a "note" section which isn't loadable. */
         for (i = 0; i < ehdr->e_phnum; i++) {
+                /* If this isn't a loadable segment, we ignore it */
                 if (phdr[i].p_type != PT_LOAD)
                         continue;
 
                 verbose("Section %i: size %i addr %p\n",
                         i, phdr[i].p_memsz, (void *)phdr[i].p_paddr);
 
-                /* We expect linear address space. */
+                /* We expect a simple linear address space: every segment must
+                 * have the same difference between virtual (p_vaddr) and
+                 * physical (p_paddr) address. */
                 if (!*page_offset)
                         *page_offset = phdr[i].p_vaddr - phdr[i].p_paddr;
                 else if (*page_offset != phdr[i].p_vaddr - phdr[i].p_paddr)
                         errx(1, "Page offset of section %i different", i);
 
+                /* We track the first and last address we mapped, so we can
+                 * tell entry_point() where to scan. */
                 if (phdr[i].p_paddr < start)
                         start = phdr[i].p_paddr;
                 if (phdr[i].p_paddr + phdr[i].p_filesz > end)
                         end = phdr[i].p_paddr + phdr[i].p_filesz;
 
-                /* We map everything private, writable. */
+                /* We map this section of the file at its physical address.  We
+                 * map it read & write even if the header says this segment is
+                 * read-only.  The kernel really wants to be writable: it
+                 * patches its own instructions which would normally be
+                 * read-only.
+                 *
+                 * MAP_PRIVATE means that the page won't be copied until a
+                 * write is done to it.  This allows us to share much of the
+                 * kernel memory between Guests. */
                 addr = mmap((void *)phdr[i].p_paddr,
                             phdr[i].p_filesz,
                             PROT_READ|PROT_WRITE|PROT_EXEC,
@@ -169,7 +249,31 @@ static unsigned long map_elf(int elf_fd, const Elf32_Ehdr *ehdr,
         return entry_point((void *)start, (void *)end, *page_offset);
 }
 
-/* This is amazingly reliable. */
+/*L:170 Prepare to be SHOCKED and AMAZED.  And possibly a trifle nauseated.
+ *
+ * We know that CONFIG_PAGE_OFFSET sets what virtual address the kernel expects
+ * to be.  We don't know what that option was, but we can figure it out
+ * approximately by looking at the addresses in the code.  I chose the common
+ * case of reading a memory location into the %eax register:
+ *
+ *  movl <some-address>, %eax
+ *
+ * This gets encoded as five bytes: "0xA1 <4-byte-address>".  For example,
+ * "0xA1 0x18 0x60 0x47 0xC0" reads the address 0xC0476018 into %eax.
+ *
+ * In this example can guess that the kernel was compiled with
+ * CONFIG_PAGE_OFFSET set to 0xC0000000 (it's always a round number).  If the
+ * kernel were larger than 16MB, we might see 0xC1 addresses show up, but our
+ * kernel isn't that bloated yet.
+ *
+ * Unfortunately, x86 has variable-length instructions, so finding this
+ * particular instruction properly involves writing a disassembler.  Instead,
+ * we rely on statistics.  We look for "0xA1" and tally the different bytes
+ * which occur 4 bytes later (the "0xC0" in our example above).  When one of
+ * those bytes appears three times, we can be reasonably confident that it
+ * forms the start of CONFIG_PAGE_OFFSET.
+ *
+ * This is amazingly reliable. */
 static unsigned long intuit_page_offset(unsigned char *img, unsigned long len)
 {
         unsigned int i, possibilities[256] = { 0 };
@@ -182,30 +286,52 @@ static unsigned long intuit_page_offset(unsigned char *img, unsigned long len)
         errx(1, "could not determine page offset");
 }
 
+/*L:160 Unfortunately the entire ELF image isn't compressed: the segments
+ * which need loading are extracted and compressed raw.  This denies us the
+ * information we need to make a fully-general loader. */
 static unsigned long unpack_bzimage(int fd, unsigned long *page_offset)
 {
         gzFile f;
         int ret, len = 0;
+        /* A bzImage always gets loaded at physical address 1M.  This is
+         * actually configurable as CONFIG_PHYSICAL_START, but as the comment
+         * there says, "Don't change this unless you know what you are doing".
+         * Indeed. */
         void *img = (void *)0x100000;
 
+        /* gzdopen takes our file descriptor (carefully placed at the start of
+         * the GZIP header we found) and returns a gzFile. */
         f = gzdopen(fd, "rb");
+        /* We read it into memory in 64k chunks until we hit the end. */
         while ((ret = gzread(f, img + len, 65536)) > 0)
                 len += ret;
         if (ret < 0)
                 err(1, "reading image from bzImage");
 
         verbose("Unpacked size %i addr %p\n", len, img);
+
+        /* Without the ELF header, we can't tell virtual-physical gap.  This is
+         * CONFIG_PAGE_OFFSET, and people do actually change it.  Fortunately,
+         * I have a clever way of figuring it out from the code itself.  */
         *page_offset = intuit_page_offset(img, len);
 
         return entry_point(img, img + len, *page_offset);
 }
 
+/*L:150 A bzImage, unlike an ELF file, is not meant to be loaded.  You're
+ * supposed to jump into it and it will unpack itself.  We can't do that
+ * because the Guest can't run the unpacking code, and adding features to
+ * lguest kills puppies, so we don't want to.
+ *
+ * The bzImage is formed by putting the decompressing code in front of the
+ * compressed kernel code.  So we can simple scan through it looking for the
+ * first "gzip" header, and start decompressing from there. */
 static unsigned long load_bzimage(int fd, unsigned long *page_offset)
 {
         unsigned char c;
         int state = 0;
 
-        /* Ugly brute force search for gzip header. */
+        /* GZIP header is 0x1F 0x8B <method> <flags>... <compressed-by>. */
         while (read(fd, &c, 1) == 1) {
                 switch (state) {
                 case 0:
@@ -222,8 +348,10 @@ static unsigned long load_bzimage(int fd, unsigned long *page_offset)
                         state++;
                         break;
                 case 9:
+                        /* Seek back to the start of the gzip header. */
                         lseek(fd, -10, SEEK_CUR);
-                        if (c != 0x03) /* Compressed under UNIX. */
+                        /* One final check: "compressed under UNIX". */
+                        if (c != 0x03)
                                 state = -1;
                         else
                                 return unpack_bzimage(fd, page_offset);
@@ -232,25 +360,43 @@ static unsigned long load_bzimage(int fd, unsigned long *page_offset)
         errx(1, "Could not find kernel in bzImage");
 }
 
+/*L:140 Loading the kernel is easy when it's a "vmlinux", but most kernels
+ * come wrapped up in the self-decompressing "bzImage" format.  With some funky
+ * coding, we can load those, too. */
 static unsigned long load_kernel(int fd, unsigned long *page_offset)
 {
         Elf32_Ehdr hdr;
 
+        /* Read in the first few bytes. */
         if (read(fd, &hdr, sizeof(hdr)) != sizeof(hdr))
                 err(1, "Reading kernel");
 
+        /* If it's an ELF file, it starts with "\177ELF" */
         if (memcmp(hdr.e_ident, ELFMAG, SELFMAG) == 0)
                 return map_elf(fd, &hdr, page_offset);
 
+        /* Otherwise we assume it's a bzImage, and try to unpack it */
         return load_bzimage(fd, page_offset);
 }
 
+/* This is a trivial little helper to align pages.  Andi Kleen hated it because
+ * it calls getpagesize() twice: "it's dumb code."
+ *
+ * Kernel guys get really het up about optimization, even when it's not
+ * necessary.  I leave this code as a reaction against that. */
 static inline unsigned long page_align(unsigned long addr)
 {
+        /* Add upwards and truncate downwards. */
         return ((addr + getpagesize()-1) & ~(getpagesize()-1));
 }
 
-/* initrd gets loaded at top of memory: return length. */
+/*L:180 An "initial ram disk" is a disk image loaded into memory along with
+ * the kernel which the kernel can use to boot from without needing any
+ * drivers.  Most distributions now use this as standard: the initrd contains
+ * the code to load the appropriate driver modules for the current machine.
+ *
+ * Importantly, James Morris works for RedHat, and Fedora uses initrds for its
+ * kernels.  He sent me this (and tells me when I break it). */
 static unsigned long load_initrd(const char *name, unsigned long mem)
 {
         int ifd;
@@ -259,21 +405,35 @@ static unsigned long load_initrd(const char *name, unsigned long mem)
         void *iaddr;
 
         ifd = open_or_die(name, O_RDONLY);
+        /* fstat() is needed to get the file size. */
         if (fstat(ifd, &st) < 0)
                 err(1, "fstat() on initrd '%s'", name);
 
+        /* The length needs to be rounded up to a page size: mmap needs the
+         * address to be page aligned. */
         len = page_align(st.st_size);
+        /* We map the initrd at the top of memory. */
         iaddr = mmap((void *)mem - len, st.st_size,
                      PROT_READ|PROT_EXEC|PROT_WRITE,
                      MAP_FIXED|MAP_PRIVATE, ifd, 0);
         if (iaddr != (void *)mem - len)
                 err(1, "Mmaping initrd '%s' returned %p not %p",
                     name, iaddr, (void *)mem - len);
+        /* Once a file is mapped, you can close the file descriptor.  It's a
+         * little odd, but quite useful. */
         close(ifd);
         verbose("mapped initrd %s size=%lu @ %p\n", name, st.st_size, iaddr);
+
+        /* We return the initrd size. */
         return len;
 }
 
+/* Once we know how much memory we have, and the address the Guest kernel
+ * expects, we can construct simple linear page tables which will get the Guest
+ * far enough into the boot to create its own.
+ *
+ * We lay them out of the way, just below the initrd (which is why we need to
+ * know its size). */
 static unsigned long setup_pagetables(unsigned long mem,
                                       unsigned long initrd_size,
                                       unsigned long page_offset)
@@ -282,23 +442,32 @@ static unsigned long setup_pagetables(unsigned long mem,
         unsigned int mapped_pages, i, linear_pages;
         unsigned int ptes_per_page = getpagesize()/sizeof(u32);
 
-        /* If we can map all of memory above page_offset, we do so. */
+        /* Ideally we map all physical memory starting at page_offset.
+         * However, if page_offset is 0xC0000000 we can only map 1G of physical
+         * (0xC0000000 + 1G overflows). */
         if (mem <= -page_offset)
                 mapped_pages = mem/getpagesize();
         else
                 mapped_pages = -page_offset/getpagesize();
 
-        /* Each linear PTE page can map ptes_per_page pages. */
+        /* Each PTE page can map ptes_per_page pages: how many do we need? */
         linear_pages = (mapped_pages + ptes_per_page-1)/ptes_per_page;
 
-        /* We lay out top-level then linear mapping immediately below initrd */
+        /* We put the toplevel page directory page at the top of memory. */
         pgdir = (void *)mem - initrd_size - getpagesize();
+
+        /* Now we use the next linear_pages pages as pte pages */
         linear = (void *)pgdir - linear_pages*getpagesize();
 
+        /* Linear mapping is easy: put every page's address into the mapping in
+         * order.  PAGE_PRESENT contains the flags Present, Writable and
+         * Executable. */
         for (i = 0; i < mapped_pages; i++)
                 linear[i] = ((i * getpagesize()) | PAGE_PRESENT);
 
-        /* Now set up pgd so that this memory is at page_offset */
+        /* The top level points to the linear page table pages above.  The
+         * entry representing page_offset points to the first one, and they
+         * continue from there. */
         for (i = 0; i < mapped_pages; i += ptes_per_page) {
                 pgdir[(i + page_offset/getpagesize())/ptes_per_page]
                         = (((u32)linear + i*sizeof(u32)) | PAGE_PRESENT);
@@ -307,9 +476,13 @@ static unsigned long setup_pagetables(unsigned long mem,
         verbose("Linear mapping of %u pages in %u pte pages at %p\n",
                 mapped_pages, linear_pages, linear);
 
+        /* We return the top level (guest-physical) address: the kernel needs
+         * to know where it is. */
         return (unsigned long)pgdir;
 }
 
+/* Simple routine to roll all the commandline arguments together with spaces
+ * between them. */
 static void concat(char *dst, char *args[])
 {
         unsigned int i, len = 0;
@@ -323,6 +496,10 @@ static void concat(char *dst, char *args[])
         dst[len] = '\0';
 }
 
+/* This is where we actually tell the kernel to initialize the Guest.  We saw
+ * the arguments it expects when we looked at initialize() in lguest_user.c:
+ * the top physical page to allow, the top level pagetable, the entry point and
+ * the page_offset constant for the Guest. */
 static int tell_kernel(u32 pgdir, u32 start, u32 page_offset)
 {
         u32 args[] = { LHREQ_INITIALIZE,
@@ -332,8 +509,11 @@ static int tell_kernel(u32 pgdir, u32 start, u32 page_offset)
         fd = open_or_die("/dev/lguest", O_RDWR);
         if (write(fd, args, sizeof(args)) < 0)
                 err(1, "Writing to /dev/lguest");
+
+        /* We return the /dev/lguest file descriptor to control this Guest */
         return fd;
 }
+/*:*/
 
 static void set_fd(int fd, struct device_list *devices)
 {
@@ -342,61 +522,108 @@ static void set_fd(int fd, struct device_list *devices)
                 devices->max_infd = fd;
 }
 
-/* When input arrives, we tell the kernel to kick lguest out with -EAGAIN. */
+/*L:200
+ * The Waker.
+ *
+ * With a console and network devices, we can have lots of input which we need
+ * to process.  We could try to tell the kernel what file descriptors to watch,
+ * but handing a file descriptor mask through to the kernel is fairly icky.
+ *
+ * Instead, we fork off a process which watches the file descriptors and writes
+ * the LHREQ_BREAK command to the /dev/lguest filedescriptor to tell the Host
+ * loop to stop running the Guest.  This causes it to return from the
+ * /dev/lguest read with -EAGAIN, where it will write to /dev/lguest to reset
+ * the LHREQ_BREAK and wake us up again.
+ *
+ * This, of course, is merely a different *kind* of icky.
+ */
 static void wake_parent(int pipefd, int lguest_fd, struct device_list *devices)
 {
+        /* Add the pipe from the Launcher to the fdset in the device_list, so
+         * we watch it, too. */
         set_fd(pipefd, devices);
 
         for (;;) {
                 fd_set rfds = devices->infds;
                 u32 args[] = { LHREQ_BREAK, 1 };
 
+                /* Wait until input is ready from one of the devices. */
                 select(devices->max_infd+1, &rfds, NULL, NULL, NULL);
+                /* Is it a message from the Launcher? */
                 if (FD_ISSET(pipefd, &rfds)) {
                         int ignorefd;
+                        /* If read() returns 0, it means the Launcher has
+                         * exited.  We silently follow. */
                         if (read(pipefd, &ignorefd, sizeof(ignorefd)) == 0)
                                 exit(0);
+                        /* Otherwise it's telling us there's a problem with one
+                         * of the devices, and we should ignore that file
+                         * descriptor from now on. */
                         FD_CLR(ignorefd, &devices->infds);
-                } else
+                } else /* Send LHREQ_BREAK command. */
                         write(lguest_fd, args, sizeof(args));
         }
 }
 
+/* This routine just sets up a pipe to the Waker process. */
 static int setup_waker(int lguest_fd, struct device_list *device_list)
 {
         int pipefd[2], child;
 
+        /* We create a pipe to talk to the waker, and also so it knows when the
+         * Launcher dies (and closes pipe). */
         pipe(pipefd);
         child = fork();
         if (child == -1)
                 err(1, "forking");
 
         if (child == 0) {
+                /* Close the "writing" end of our copy of the pipe */
                 close(pipefd[1]);
                 wake_parent(pipefd[0], lguest_fd, device_list);
         }
+        /* Close the reading end of our copy of the pipe. */
         close(pipefd[0]);
 
+        /* Here is the fd used to talk to the waker. */
         return pipefd[1];
 }
 
+/*L:210
+ * Device Handling.
+ *
+ * When the Guest sends DMA to us, it sends us an array of addresses and sizes.
+ * We need to make sure it's not trying to reach into the Launcher itself, so
+ * we have a convenient routine which check it and exits with an error message
+ * if something funny is going on:
+ */
 static void *_check_pointer(unsigned long addr, unsigned int size,
                             unsigned int line)
 {
+        /* We have to separately check addr and addr+size, because size could
+         * be huge and addr + size might wrap around. */
         if (addr >= top || addr + size >= top)
                 errx(1, "%s:%i: Invalid address %li", __FILE__, line, addr);
+        /* We return a pointer for the caller's convenience, now we know it's
+         * safe to use. */
         return (void *)addr;
 }
+/* A macro which transparently hands the line number to the real function. */
 #define check_pointer(addr,size) _check_pointer(addr, size, __LINE__)
 
-/* Returns pointer to dma->used_len */
+/* The Guest has given us the address of a "struct lguest_dma".  We check it's
+ * OK and convert it to an iovec (which is a simple array of ptr/size
+ * pairs). */
 static u32 *dma2iov(unsigned long dma, struct iovec iov[], unsigned *num)
 {
         unsigned int i;
         struct lguest_dma *udma;
 
+        /* First we make sure that the array memory itself is valid. */
         udma = check_pointer(dma, sizeof(*udma));
+        /* Now we check each element */
         for (i = 0; i < LGUEST_MAX_DMA_SECTIONS; i++) {
+                /* A zero length ends the array. */
                 if (!udma->len[i])
                         break;
 
@@ -404,9 +631,15 @@ static u32 *dma2iov(unsigned long dma, struct iovec iov[], unsigned *num)
                 iov[i].iov_len = udma->len[i];
         }
         *num = i;
+
+        /* We return the pointer to where the caller should write the amount of
+         * the buffer used. */
         return &udma->used_len;
 }
 
+/* This routine gets a DMA buffer from the Guest for a given key, and converts
+ * it to an iovec array.  It returns the interrupt the Guest wants when we're
+ * finished, and a pointer to the "used_len" field to fill in. */
 static u32 *get_dma_buffer(int fd, void *key,
                            struct iovec iov[], unsigned int *num, u32 *irq)
 {
@@ -414,16 +647,21 @@ static u32 *get_dma_buffer(int fd, void *key,
         unsigned long udma;
         u32 *res;
 
+        /* Ask the kernel for a DMA buffer corresponding to this key. */
         udma = write(fd, buf, sizeof(buf));
+        /* They haven't registered any, or they're all used? */
         if (udma == (unsigned long)-1)
                 return NULL;
 
-        /* Kernel stashes irq in ->used_len. */
+        /* Convert it into our iovec array */
         res = dma2iov(udma, iov, num);
+        /* The kernel stashes irq in ->used_len to get it out to us. */
         *irq = *res;
+        /* Return a pointer to ((struct lguest_dma *)udma)->used_len. */
         return res;
 }
 
+/* This is a convenient routine to send the Guest an interrupt. */
 static void trigger_irq(int fd, u32 irq)
 {
         u32 buf[] = { LHREQ_IRQ, irq };
@@ -431,6 +669,10 @@ static void trigger_irq(int fd, u32 irq)
                 err(1, "Triggering irq %i", irq);
 }
 
+/* This simply sets up an iovec array where we can put data to be discarded.
+ * This happens when the Guest doesn't want or can't handle the input: we have
+ * to get rid of it somewhere, and if we bury it in the ceiling space it will
+ * start to smell after a week. */
 static void discard_iovec(struct iovec *iov, unsigned int *num)
 {
         static char discard_buf[1024];
@@ -439,19 +681,24 @@ static void discard_iovec(struct iovec *iov, unsigned int *num)
         iov->iov_len = sizeof(discard_buf);
 }
 
+/* Here is the input terminal setting we save, and the routine to restore them
+ * on exit so the user can see what they type next. */
 static struct termios orig_term;
 static void restore_term(void)
 {
         tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
 }
 
+/* We associate some data with the console for our exit hack. */
 struct console_abort
 {
+        /* How many times have they hit ^C? */
         int count;
+        /* When did they start? */
         struct timeval start;
 };
 
-/* We DMA input to buffer bound at start of console page. */
+/* This is the routine which handles console input (ie. stdin). */
 static bool handle_console_input(int fd, struct device *dev)
 {
         u32 irq = 0, *lenp;
@@ -460,24 +707,38 @@ static bool handle_console_input(int fd, struct device *dev)
         struct iovec iov[LGUEST_MAX_DMA_SECTIONS];
         struct console_abort *abort = dev->priv;
 
+        /* First we get the console buffer from the Guest.  The key is dev->mem
+         * which was set to 0 in setup_console(). */
         lenp = get_dma_buffer(fd, dev->mem, iov, &num, &irq);
         if (!lenp) {
+                /* If it's not ready for input, warn and set up to discard. */
                 warn("console: no dma buffer!");
                 discard_iovec(iov, &num);
         }
 
+        /* This is why we convert to iovecs: the readv() call uses them, and so
+         * it reads straight into the Guest's buffer. */
         len = readv(dev->fd, iov, num);
         if (len <= 0) {
+                /* This implies that the console is closed, is /dev/null, or
+                 * something went terribly wrong.  We still go through the rest
+                 * of the logic, though, especially the exit handling below. */
                 warnx("Failed to get console input, ignoring console.");
                 len = 0;
         }
 
+        /* If we read the data into the Guest, fill in the length and send the
+         * interrupt. */
         if (lenp) {
                 *lenp = len;
                 trigger_irq(fd, irq);
         }
 
-        /* Three ^C within one second?  Exit. */
+        /* Three ^C within one second?  Exit.
+         *
+         * This is such a hack, but works surprisingly well.  Each ^C has to be
+         * in a buffer by itself, so they can't be too fast.  But we check that
+         * we get three within about a second, so they can't be too slow. */
         if (len == 1 && ((char *)iov[0].iov_base)[0] == 3) {
                 if (!abort->count++)
                         gettimeofday(&abort->start, NULL);
@@ -485,43 +746,60 @@ static bool handle_console_input(int fd, struct device *dev)
                         struct timeval now;
                         gettimeofday(&now, NULL);
                         if (now.tv_sec <= abort->start.tv_sec+1) {
-                                /* Make sure waker is not blocked in BREAK */
                                 u32 args[] = { LHREQ_BREAK, 0 };
+                                /* Close the fd so Waker will know it has to
+                                 * exit. */
                                 close(waker_fd);
+                                /* Just in case waker is blocked in BREAK, send
+                                 * unbreak now. */
                                 write(fd, args, sizeof(args));
                                 exit(2);
                         }
                         abort->count = 0;
                 }
         } else
+                /* Any other key resets the abort counter. */
                 abort->count = 0;
 
+        /* Now, if we didn't read anything, put the input terminal back and
+         * return failure (meaning, don't call us again). */
         if (!len) {
                 restore_term();
                 return false;
         }
+        /* Everything went OK! */
         return true;
 }
 
+/* Handling console output is much simpler than input. */
 static u32 handle_console_output(int fd, const struct iovec *iov,
                                  unsigned num, struct device*dev)
 {
+        /* Whatever the Guest sends, write it to standard output.  Return the
+         * number of bytes written. */
         return writev(STDOUT_FILENO, iov, num);
 }
 
+/* Guest->Host network output is also pretty easy. */
 static u32 handle_tun_output(int fd, const struct iovec *iov,
                              unsigned num, struct device *dev)
 {
-        /* Now we've seen output, we should warn if we can't get buffers. */
+        /* We put a flag in the "priv" pointer of the network device, and set
+         * it as soon as we see output.  We'll see why in handle_tun_input() */
         *(bool *)dev->priv = true;
+        /* Whatever packet the Guest sent us, write it out to the tun
+         * device. */
         return writev(dev->fd, iov, num);
 }
 
+/* This matches the peer_key() in lguest_net.c.  The key for any given slot
+ * is the address of the network device's page plus 4 * the slot number. */
 static unsigned long peer_offset(unsigned int peernum)
 {
         return 4 * peernum;
 }
 
+/* This is where we handle a packet coming in from the tun device */
 static bool handle_tun_input(int fd, struct device *dev)
 {
         u32 irq = 0, *lenp;
@@ -529,17 +807,28 @@ static bool handle_tun_input(int fd, struct device *dev)
         unsigned num;
         struct iovec iov[LGUEST_MAX_DMA_SECTIONS];
 
+        /* First we get a buffer the Guest has bound to its key. */
         lenp = get_dma_buffer(fd, dev->mem+peer_offset(NET_PEERNUM), iov, &num,
                               &irq);
         if (!lenp) {
+                /* Now, it's expected that if we try to send a packet too
+                 * early, the Guest won't be ready yet.  This is why we set a
+                 * flag when the Guest sends its first packet.  If it's sent a
+                 * packet we assume it should be ready to receive them.
+                 *
+                 * Actually, this is what the status bits in the descriptor are
+                 * for: we should *use* them.  FIXME! */
                 if (*(bool *)dev->priv)
                         warn("network: no dma buffer!");
                 discard_iovec(iov, &num);
         }
 
+        /* Read the packet from the device directly into the Guest's buffer. */
         len = readv(dev->fd, iov, num);
         if (len <= 0)
                 err(1, "reading network");
+
+        /* Write the used_len, and trigger the interrupt for the Guest */
         if (lenp) {
                 *lenp = len;
                 trigger_irq(fd, irq);
@@ -547,9 +836,13 @@ static bool handle_tun_input(int fd, struct device *dev)
         verbose("tun input packet len %i [%02x %02x] (%s)\n", len,
                 ((u8 *)iov[0].iov_base)[0], ((u8 *)iov[0].iov_base)[1],
                 lenp ? "sent" : "discarded");
+        /* All good. */
         return true;
 }
 
+/* The last device handling routine is block output: the Guest has sent a DMA
+ * to the block device.  It will have placed the command it wants in the
+ * "struct lguest_block_page". */
 static u32 handle_block_output(int fd, const struct iovec *iov,
                                unsigned num, struct device *dev)
 {
@@ -559,36 +852,64 @@ static u32 handle_block_output(int fd, const struct iovec *iov,
         struct iovec reply[LGUEST_MAX_DMA_SECTIONS];
         off64_t device_len, off = (off64_t)p->sector * 512;
 
+        /* First we extract the device length from the dev->priv pointer. */
         device_len = *(off64_t *)dev->priv;
 
+        /* We first check that the read or write is within the length of the
+         * block file. */
         if (off >= device_len)
                 err(1, "Bad offset %llu vs %llu", off, device_len);
+        /* Move to the right location in the block file.  This shouldn't fail,
+         * but best to check. */
         if (lseek64(dev->fd, off, SEEK_SET) != off)
                 err(1, "Bad seek to sector %i", p->sector);
 
         verbose("Block: %s at offset %llu\n", p->type ? "WRITE" : "READ", off);
 
+        /* They were supposed to bind a reply buffer at key equal to the start
+         * of the block device memory.  We need this to tell them when the
+         * request is finished. */
         lenp = get_dma_buffer(fd, dev->mem, reply, &reply_num, &irq);
         if (!lenp)
                 err(1, "Block request didn't give us a dma buffer");
 
         if (p->type) {
+                /* A write request.  The DMA they sent contained the data, so
+                 * write it out. */
                 len = writev(dev->fd, iov, num);
+                /* Grr... Now we know how long the "struct lguest_dma" they
+                 * sent was, we make sure they didn't try to write over the end
+                 * of the block file (possibly extending it). */
                 if (off + len > device_len) {
+                        /* Trim it back to the correct length */
                         ftruncate(dev->fd, device_len);
+                        /* Die, bad Guest, die. */
                         errx(1, "Write past end %llu+%u", off, len);
                 }
+                /* The reply length is 0: we just send back an empty DMA to
+                 * interrupt them and tell them the write is finished. */
                 *lenp = 0;
         } else {
+                /* A read request.  They sent an empty DMA to start the
+                 * request, and we put the read contents into the reply
+                 * buffer. */
                 len = readv(dev->fd, reply, reply_num);
                 *lenp = len;
         }
 
+        /* The result is 1 (done), 2 if there was an error (short read or
+         * write). */
         p->result = 1 + (p->bytes != len);
+        /* Now tell them we've used their reply buffer. */
         trigger_irq(fd, irq);
+
+        /* We're supposed to return the number of bytes of the output buffer we
+         * used.  But the block device uses the "result" field instead, so we
+         * don't bother. */
         return 0;
 }
 
+/* This is the generic routine we call when the Guest sends some DMA out. */
 static void handle_output(int fd, unsigned long dma, unsigned long key,
                           struct device_list *devices)
 {
@@ -597,30 +918,53 @@ static void handle_output(int fd, unsigned long dma, unsigned long key,
         struct iovec iov[LGUEST_MAX_DMA_SECTIONS];
         unsigned num = 0;
 
+        /* Convert the "struct lguest_dma" they're sending to a "struct
+         * iovec". */
         lenp = dma2iov(dma, iov, &num);
+
+        /* Check each device: if they expect output to this key, tell them to
+         * handle it. */
         for (i = devices->dev; i; i = i->next) {
                 if (i->handle_output && key == i->watch_key) {
+                        /* We write the result straight into the used_len field
+                         * for them. */
                         *lenp = i->handle_output(fd, iov, num, i);
                         return;
                 }
         }
+
+        /* This can happen: the kernel sends any SEND_DMA which doesn't match
+         * another Guest to us.  It could be that another Guest just left a
+         * network, for example.  But it's unusual. */
         warnx("Pending dma %p, key %p", (void *)dma, (void *)key);
 }
 
+/* This is called when the waker wakes us up: check for incoming file
+ * descriptors. */
 static void handle_input(int fd, struct device_list *devices)
 {
+        /* select() wants a zeroed timeval to mean "don't wait". */
         struct timeval poll = { .tv_sec = 0, .tv_usec = 0 };
 
         for (;;) {
                 struct device *i;
                 fd_set fds = devices->infds;
 
+                /* If nothing is ready, we're done. */
                 if (select(devices->max_infd+1, &fds, NULL, NULL, &poll) == 0)
                         break;
 
+                /* Otherwise, call the device(s) which have readable
+                 * file descriptors and a method of handling them.  */
                 for (i = devices->dev; i; i = i->next) {
                         if (i->handle_input && FD_ISSET(i->fd, &fds)) {
+                                /* If handle_input() returns false, it means we
+                                 * should no longer service it.
+                                 * handle_console_input() does this. */
                                 if (!i->handle_input(fd, i)) {
+                                        /* Clear it from the set of input file
+                                         * descriptors kept at the head of the
+                                         * device list. */
                                         FD_CLR(i->fd, &devices->infds);
                                         /* Tell waker to ignore it too... */
                                         write(waker_fd, &i->fd, sizeof(i->fd));
@@ -630,6 +974,15 @@ static void handle_input(int fd, struct device_list *devices)
         }
 }
 
+/*L:190
+ * Device Setup
+ *
+ * All devices need a descriptor so the Guest knows it exists, and a "struct
+ * device" so the Launcher can keep track of it.  We have common helper
+ * routines to allocate them.
+ *
+ * This routine allocates a new "struct lguest_device_desc" from descriptor
+ * table in the devices array just above the Guest's normal memory. */
 static struct lguest_device_desc *
 new_dev_desc(struct lguest_device_desc *descs,
              u16 type, u16 features, u16 num_pages)
@@ -641,6 +994,8 @@ new_dev_desc(struct lguest_device_desc *descs,
                         descs[i].type = type;
                         descs[i].features = features;
                         descs[i].num_pages = num_pages;
+                        /* If they said the device needs memory, we allocate
+                         * that now, bumping up the top of Guest memory. */
                         if (num_pages) {
                                 map_zeroed_pages(top, num_pages);
                                 descs[i].pfn = top/getpagesize();
@@ -652,6 +1007,9 @@ new_dev_desc(struct lguest_device_desc *descs,
         errx(1, "too many devices");
 }
 
+/* This monster routine does all the creation and setup of a new device,
+ * including caling new_dev_desc() to allocate the descriptor and device
+ * memory. */
 static struct device *new_device(struct device_list *devices,
                                  u16 type, u16 num_pages, u16 features,
                                  int fd,
@@ -664,12 +1022,18 @@ static struct device *new_device(struct device_list *devices,
 {
         struct device *dev = malloc(sizeof(*dev));
 
-        /* Append to device list. */
+        /* Append to device list.  Prepending to a single-linked list is
+         * easier, but the user expects the devices to be arranged on the bus
+         * in command-line order.  The first network device on the command line
+         * is eth0, the first block device /dev/lgba, etc. */
         *devices->lastdev = dev;
         dev->next = NULL;
         devices->lastdev = &dev->next;
 
+        /* Now we populate the fields one at a time. */
         dev->fd = fd;
+        /* If we have an input handler for this file descriptor, then we add it
+         * to the device_list's fdset and maxfd. */
         if (handle_input)
                 set_fd(dev->fd, devices);
         dev->desc = new_dev_desc(devices->descs, type, features, num_pages);
@@ -680,27 +1044,37 @@ static struct device *new_device(struct device_list *devices,
         return dev;
 }
 
+/* Our first setup routine is the console.  It's a fairly simple device, but
+ * UNIX tty handling makes it uglier than it could be. */
 static void setup_console(struct device_list *devices)
 {
         struct device *dev;
 
+        /* If we can save the initial standard input settings... */
         if (tcgetattr(STDIN_FILENO, &orig_term) == 0) {
                 struct termios term = orig_term;
+                /* Then we turn off echo, line buffering and ^C etc.  We want a
+                 * raw input stream to the Guest. */
                 term.c_lflag &= ~(ISIG|ICANON|ECHO);
                 tcsetattr(STDIN_FILENO, TCSANOW, &term);
+                /* If we exit gracefully, the original settings will be
+                 * restored so the user can see what they're typing. */
                 atexit(restore_term);
         }
 
-        /* We don't currently require a page for the console. */
+        /* We don't currently require any memory for the console, so we ask for
+         * 0 pages. */
         dev = new_device(devices, LGUEST_DEVICE_T_CONSOLE, 0, 0,
                          STDIN_FILENO, handle_console_input,
                          LGUEST_CONSOLE_DMA_KEY, handle_console_output);
+        /* We store the console state in dev->priv, and initialize it. */
         dev->priv = malloc(sizeof(struct console_abort));
         ((struct console_abort *)dev->priv)->count = 0;
         verbose("device %p: console\n",
                 (void *)(dev->desc->pfn * getpagesize()));
 }
 
+/* Setting up a block file is also fairly straightforward. */
 static void setup_block_file(const char *filename, struct device_list *devices)
 {
         int fd;
@@ -708,20 +1082,47 @@ static void setup_block_file(const char *filename, struct device_list *devices)
         off64_t *device_len;
         struct lguest_block_page *p;
 
+        /* We open with O_LARGEFILE because otherwise we get stuck at 2G.  We
+         * open with O_DIRECT because otherwise our benchmarks go much too
+         * fast. */
         fd = open_or_die(filename, O_RDWR|O_LARGEFILE|O_DIRECT);
+
+        /* We want one page, and have no input handler (the block file never
+         * has anything interesting to say to us).  Our timing will be quite
+         * random, so it should be a reasonable randomness source. */
         dev = new_device(devices, LGUEST_DEVICE_T_BLOCK, 1,
                          LGUEST_DEVICE_F_RANDOMNESS,
                          fd, NULL, 0, handle_block_output);
+
+        /* We store the device size in the private area */
         device_len = dev->priv = malloc(sizeof(*device_len));
+        /* This is the safe way of establishing the size of our device: it
+         * might be a normal file or an actual block device like /dev/hdb. */
         *device_len = lseek64(fd, 0, SEEK_END);
-        p = dev->mem;
 
+        /* The device memory is a "struct lguest_block_page".  It's zeroed
+         * already, we just need to put in the device size.  Block devices
+         * think in sectors (ie. 512 byte chunks), so we translate here. */
+        p = dev->mem;
         p->num_sectors = *device_len/512;
         verbose("device %p: block %i sectors\n",
                 (void *)(dev->desc->pfn * getpagesize()), p->num_sectors);
 }
 
-/* We use fnctl locks to reserve network slots (autocleanup!) */
+/*
+ * Network Devices.
+ *
+ * Setting up network devices is quite a pain, because we have three types.
+ * First, we have the inter-Guest network.  This is a file which is mapped into
+ * the address space of the Guests who are on the network.  Because it is a
+ * shared mapping, the same page underlies all the devices, and they can send
+ * DMA to each other.
+ *
+ * Remember from our network driver, the Guest is told what slot in the page it
+ * is to use.  We use exclusive fnctl locks to reserve a slot.  If another
+ * Guest is using a slot, the lock will fail and we try another.  Because fnctl
+ * locks are cleaned up automatically when we die, this cleverly means that our
+ * reservation on the slot will vanish if we crash. */
 static unsigned int find_slot(int netfd, const char *filename)
 {
         struct flock fl;
@@ -729,26 +1130,33 @@ static unsigned int find_slot(int netfd, const char *filename)
         fl.l_type = F_WRLCK;
         fl.l_whence = SEEK_SET;
         fl.l_len = 1;
+        /* Try a 1 byte lock in each possible position number */
         for (fl.l_start = 0;
              fl.l_start < getpagesize()/sizeof(struct lguest_net);
              fl.l_start++) {
+                /* If we succeed, return the slot number. */
                 if (fcntl(netfd, F_SETLK, &fl) == 0)
                         return fl.l_start;
         }
         errx(1, "No free slots in network file %s", filename);
 }
 
+/* This function sets up the network file */
 static void setup_net_file(const char *filename,
                            struct device_list *devices)
 {
         int netfd;
         struct device *dev;
 
+        /* We don't use open_or_die() here: for friendliness we create the file
+         * if it doesn't already exist. */
         netfd = open(filename, O_RDWR, 0);
         if (netfd < 0) {
                 if (errno == ENOENT) {
                         netfd = open(filename, O_RDWR|O_CREAT, 0600);
                         if (netfd >= 0) {
+                                /* If we succeeded, initialize the file with a
+                                 * blank page. */
                                 char page[getpagesize()];
                                 memset(page, 0, sizeof(page));
                                 write(netfd, page, sizeof(page));
@@ -758,11 +1166,15 @@ static void setup_net_file(const char *filename,
                         err(1, "cannot open net file '%s'", filename);
         }
 
+        /* We need 1 page, and the features indicate the slot to use and that
+         * no checksum is needed.  We never touch this device again; it's
+         * between the Guests on the network, so we don't register input or
+         * output handlers. */
         dev = new_device(devices, LGUEST_DEVICE_T_NET, 1,
                          find_slot(netfd, filename)|LGUEST_NET_F_NOCSUM,
                          -1, NULL, 0, NULL);
 
-        /* We overwrite the /dev/zero mapping with the actual file. */
+        /* Map the shared file. */
         if (mmap(dev->mem, getpagesize(), PROT_READ|PROT_WRITE,
                          MAP_FIXED|MAP_SHARED, netfd, 0) != dev->mem)
                         err(1, "could not mmap '%s'", filename);
@@ -770,6 +1182,7 @@ static void setup_net_file(const char *filename,
                 (void *)(dev->desc->pfn * getpagesize()), filename,
                 dev->desc->features & ~LGUEST_NET_F_NOCSUM);
 }
+/*:*/
 
 static u32 str2ip(const char *ipaddr)
 {
@@ -779,7 +1192,11 @@ static u32 str2ip(const char *ipaddr)
         return (byte[0] << 24) | (byte[1] << 16) | (byte[2] << 8) | byte[3];
 }
 
-/* adapted from libbridge */
+/* This code is "adapted" from libbridge: it attaches the Host end of the
+ * network device to the bridge device specified by the command line.
+ *
+ * This is yet another James Morris contribution (I'm an IP-level guy, so I
+ * dislike bridging), and I just try not to break it. */
 static void add_to_bridge(int fd, const char *if_name, const char *br_name)
 {
         int ifidx;
@@ -798,12 +1215,16 @@ static void add_to_bridge(int fd, const char *if_name, const char *br_name)
                 err(1, "can't add %s to bridge %s", if_name, br_name);
 }
 
+/* This sets up the Host end of the network device with an IP address, brings
+ * it up so packets will flow, the copies the MAC address into the hwaddr
+ * pointer (in practice, the Host's slot in the network device's memory). */
 static void configure_device(int fd, const char *devname, u32 ipaddr,
                              unsigned char hwaddr[6])
 {
         struct ifreq ifr;
         struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
 
+        /* Don't read these incantations.  Just cut & paste them like I did! */
         memset(&ifr, 0, sizeof(ifr));
         strcpy(ifr.ifr_name, devname);
         sin->sin_family = AF_INET;
@@ -814,12 +1235,19 @@ static void configure_device(int fd, const char *devname, u32 ipaddr,
         if (ioctl(fd, SIOCSIFFLAGS, &ifr) != 0)
                 err(1, "Bringing interface %s up", devname);
 
+        /* SIOC stands for Socket I/O Control.  G means Get (vs S for Set
+         * above).  IF means Interface, and HWADDR is hardware address.
+         * Simple! */
         if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0)
                 err(1, "getting hw address for %s", devname);
-
         memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, 6);
 }
 
+/*L:195 The other kind of network is a Host<->Guest network.  This can either
+ * use briding or routing, but the principle is the same: it uses the "tun"
+ * device to inject packets into the Host as if they came in from a normal
+ * network card.  We just shunt packets between the Guest and the tun
+ * device. */
 static void setup_tun_net(const char *arg, struct device_list *devices)
 {
         struct device *dev;
@@ -828,36 +1256,56 @@ static void setup_tun_net(const char *arg, struct device_list *devices)
         u32 ip;
         const char *br_name = NULL;
 
+        /* We open the /dev/net/tun device and tell it we want a tap device.  A
+         * tap device is like a tun device, only somehow different.  To tell
+         * the truth, I completely blundered my way through this code, but it
+         * works now! */
         netfd = open_or_die("/dev/net/tun", O_RDWR);
         memset(&ifr, 0, sizeof(ifr));
         ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
         strcpy(ifr.ifr_name, "tap%d");
         if (ioctl(netfd, TUNSETIFF, &ifr) != 0)
                 err(1, "configuring /dev/net/tun");
+        /* We don't need checksums calculated for packets coming in this
+         * device: trust us! */
         ioctl(netfd, TUNSETNOCSUM, 1);
 
-        /* You will be peer 1: we should create enough jitter to randomize */
+        /* We create the net device with 1 page, using the features field of
+         * the descriptor to tell the Guest it is in slot 1 (NET_PEERNUM), and
+         * that the device has fairly random timing.  We do *not* specify
+         * LGUEST_NET_F_NOCSUM: these packets can reach the real world.
+         *
+         * We will put our MAC address is slot 0 for the Guest to see, so
+         * it will send packets to us using the key "peer_offset(0)": */
         dev = new_device(devices, LGUEST_DEVICE_T_NET, 1,
                          NET_PEERNUM|LGUEST_DEVICE_F_RANDOMNESS, netfd,
                          handle_tun_input, peer_offset(0), handle_tun_output);
+
+        /* We keep a flag which says whether we've seen packets come out from
+         * this network device. */
         dev->priv = malloc(sizeof(bool));
         *(bool *)dev->priv = false;
 
+        /* We need a socket to perform the magic network ioctls to bring up the
+         * tap interface, connect to the bridge etc.  Any socket will do! */
         ipfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
         if (ipfd < 0)
                 err(1, "opening IP socket");
 
+        /* If the command line was --tunnet=bridge:<name> do bridging. */
         if (!strncmp(BRIDGE_PFX, arg, strlen(BRIDGE_PFX))) {
                 ip = INADDR_ANY;
                 br_name = arg + strlen(BRIDGE_PFX);
                 add_to_bridge(ipfd, ifr.ifr_name, br_name);
-        } else
+        } else /* It is an IP address to set up the device with */
                 ip = str2ip(arg);
 
-        /* We are peer 0, ie. first slot. */
+        /* We are peer 0, ie. first slot, so we hand dev->mem to this routine
+         * to write the MAC address at the start of the device memory.  */
         configure_device(ipfd, ifr.ifr_name, ip, dev->mem);
 
-        /* Set "promisc" bit: we want every single packet. */
+        /* Set "promisc" bit: we want every single packet if we're going to
+         * bridge to other machines (and otherwise it doesn't matter). */
         *((u8 *)dev->mem) |= 0x1;
 
         close(ipfd);
@@ -868,7 +1316,10 @@ static void setup_tun_net(const char *arg, struct device_list *devices)
         if (br_name)
                 verbose("attached to bridge: %s\n", br_name);
 }
+/* That's the end of device setup. */
 
+/*L:220 Finally we reach the core of the Launcher, which runs the Guest, serves
+ * its input and output, and finally, lays it to rest. */
 static void __attribute__((noreturn))
 run_guest(int lguest_fd, struct device_list *device_list)
 {
@@ -880,20 +1331,37 @@ run_guest(int lguest_fd, struct device_list *device_list)
                 /* We read from the /dev/lguest device to run the Guest. */
                 readval = read(lguest_fd, arr, sizeof(arr));
 
+                /* The read can only really return sizeof(arr) (the Guest did a
+                 * SEND_DMA to us), or an error. */
+
+                /* For a successful read, arr[0] is the address of the "struct
+                 * lguest_dma", and arr[1] is the key the Guest sent to. */
                 if (readval == sizeof(arr)) {
                         handle_output(lguest_fd, arr[0], arr[1], device_list);
                         continue;
+                /* ENOENT means the Guest died.  Reading tells us why. */
                 } else if (errno == ENOENT) {
                         char reason[1024] = { 0 };
                         read(lguest_fd, reason, sizeof(reason)-1);
                         errx(1, "%s", reason);
+                /* EAGAIN means the waker wanted us to look at some input.
+                 * Anything else means a bug or incompatible change. */
                 } else if (errno != EAGAIN)
                         err(1, "Running guest failed");
+
+                /* Service input, then unset the BREAK which releases
+                 * the Waker. */
                 handle_input(lguest_fd, device_list);
                 if (write(lguest_fd, args, sizeof(args)) < 0)
                         err(1, "Resetting break");
         }
 }
+/*
+ * This is the end of the Launcher.
+ *
+ * But wait!  We've seen I/O from the Launcher, and we've seen I/O from the
+ * Drivers.  If we were to see the Host kernel I/O code, our understanding
+ * would be complete... :*/
 
 static struct option opts[] = {
         { "verbose", 0, NULL, 'v' },
@@ -911,20 +1379,49 @@ static void usage(void)
              "<mem-in-mb> vmlinux [args...]");
 }
 
+/*L:100 The Launcher code itself takes us out into userspace, that scary place
+ * where pointers run wild and free!  Unfortunately, like most userspace
+ * programs, it's quite boring (which is why everyone like to hack on the
+ * kernel!).  Perhaps if you make up an Lguest Drinking Game at this point, it
+ * will get you through this section.  Or, maybe not.
+ *
+ * The Launcher binary sits up high, usually starting at address 0xB8000000.
+ * Everything below this is the "physical" memory for the Guest.  For example,
+ * if the Guest were to write a "1" at physical address 0, we would see a "1"
+ * in the Launcher at "(int *)0".  Guest physical == Launcher virtual.
+ *
+ * This can be tough to get your head around, but usually it just means that we
+ * don't need to do any conversion when the Guest gives us it's "physical"
+ * addresses.
+ */
 int main(int argc, char *argv[])
 {
+        /* Memory, top-level pagetable, code startpoint, PAGE_OFFSET and size
+         * of the (optional) initrd. */
         unsigned long mem = 0, pgdir, start, page_offset, initrd_size = 0;
+        /* A temporary and the /dev/lguest file descriptor. */
         int i, c, lguest_fd;
+        /* The list of Guest devices, based on command line arguments. */
         struct device_list device_list;
+        /* The boot information for the Guest: at guest-physical address 0. */
         void *boot = (void *)0;
+        /* If they specify an initrd file to load. */
         const char *initrd_name = NULL;
 
+        /* First we initialize the device list.  Since console and network
+         * device receive input from a file descriptor, we keep an fdset
+         * (infds) and the maximum fd number (max_infd) with the head of the
+         * list.  We also keep a pointer to the last device, for easy appending
+         * to the list. */
         device_list.max_infd = -1;
         device_list.dev = NULL;
         device_list.lastdev = &device_list.dev;
         FD_ZERO(&device_list.infds);
 
-        /* We need to know how much memory so we can allocate devices. */
+        /* We need to know how much memory so we can set up the device
+         * descriptor and memory pages for the devices as we parse the command
+         * line.  So we quickly look through the arguments to find the amount
+         * of memory now. */
         for (i = 1; i < argc; i++) {
                 if (argv[i][0] != '-') {
                         mem = top = atoi(argv[i]) * 1024 * 1024;
@@ -933,6 +1430,8 @@ int main(int argc, char *argv[])
                         break;
                 }
         }
+
+        /* The options are fairly straight-forward */
         while ((c = getopt_long(argc, argv, "v", opts, NULL)) != EOF) {
                 switch (c) {
                 case 'v':
@@ -955,42 +1454,71 @@ int main(int argc, char *argv[])
                         usage();
                 }
         }
+        /* After the other arguments we expect memory and kernel image name,
+         * followed by command line arguments for the kernel. */
         if (optind + 2 > argc)
                 usage();
 
-        /* We need a console device */
+        /* We always have a console device */
         setup_console(&device_list);
 
-        /* First we map /dev/zero over all of guest-physical memory. */
+        /* We start by mapping anonymous pages over all of guest-physical
+         * memory range.  This fills it with 0, and ensures that the Guest
+         * won't be killed when it tries to access it. */
         map_zeroed_pages(0, mem / getpagesize());
 
         /* Now we load the kernel */
         start = load_kernel(open_or_die(argv[optind+1], O_RDONLY),
                             &page_offset);
 
-        /* Map the initrd image if requested */
+        /* Map the initrd image if requested (at top of physical memory) */
         if (initrd_name) {
                 initrd_size = load_initrd(initrd_name, mem);
+                /* These are the location in the Linux boot header where the
+                 * start and size of the initrd are expected to be found. */
                 *(unsigned long *)(boot+0x218) = mem - initrd_size;
                 *(unsigned long *)(boot+0x21c) = initrd_size;
+                /* The bootloader type 0xFF means "unknown"; that's OK. */
                 *(unsigned char *)(boot+0x210) = 0xFF;
         }
 
-        /* Set up the initial linar pagetables. */
+        /* Set up the initial linear pagetables, starting below the initrd. */
         pgdir = setup_pagetables(mem, initrd_size, page_offset);
 
-        /* E820 memory map: ours is a simple, single region. */
+        /* The Linux boot header contains an "E820" memory map: ours is a
+         * simple, single region. */
         *(char*)(boot+E820NR) = 1;
         *((struct e820entry *)(boot+E820MAP))
                 = ((struct e820entry) { 0, mem, E820_RAM });
-        /* Command line pointer and command line (at 4096) */
+        /* The boot header contains a command line pointer: we put the command
+         * line after the boot header (at address 4096) */
         *(void **)(boot + 0x228) = boot + 4096;
         concat(boot + 4096, argv+optind+2);
-        /* Paravirt type: 1 == lguest */
+
+        /* The guest type value of "1" tells the Guest it's under lguest. */
         *(int *)(boot + 0x23c) = 1;
 
+        /* We tell the kernel to initialize the Guest: this returns the open
+         * /dev/lguest file descriptor. */
         lguest_fd = tell_kernel(pgdir, start, page_offset);
+
+        /* We fork off a child process, which wakes the Launcher whenever one
+         * of the input file descriptors needs attention.  Otherwise we would
+         * run the Guest until it tries to output something. */
         waker_fd = setup_waker(lguest_fd, &device_list);
 
+        /* Finally, run the Guest.  This doesn't return. */
         run_guest(lguest_fd, &device_list);
 }
+/*:*/
+
+/*M:999
+ * Mastery is done: you now know everything I do.
+ *
+ * But surely you have seen code, features and bugs in your wanderings which
+ * you now yearn to attack?  That is the real game, and I look forward to you
+ * patching and forking lguest into the Your-Name-Here-visor.
+ *
+ * Farewell, and good coding!
+ * Rusty Russell.
+ */
diff --git a/MAINTAINERS b/MAINTAINERS
index 01f222e51871..babd00b0c65c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3339,6 +3339,14 @@ M:	thomas@winischhofer.net
 W:      http://www.winischhofer.at/linuxsisusbvga.shtml
 S:      Maintained
 
+SLAB ALLOCATOR
+P:      Christoph Lameter
+M:      clameter@sgi.com
+P:      Pekka Enberg
+M:      penberg@cs.helsinki.fi
+L:      linux-mm@kvack.org
+S:      Maintained
+
 SMC91x ETHERNET DRIVER
 P:      Nicolas Pitre
 M:      nico@cam.org
diff --git a/arch/alpha/kernel/head.S b/arch/alpha/kernel/head.S
index e27d23c74ba8..7ac1f1372c36 100644
--- a/arch/alpha/kernel/head.S
+++ b/arch/alpha/kernel/head.S
@@ -10,6 +10,7 @@
 #include <asm/system.h>
 #include <asm/asm-offsets.h>
 
+.section .text.head, "ax"
 .globl swapper_pg_dir
 .globl _stext
 swapper_pg_dir=SWAPPER_PGD
diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
index ab642a4f08de..9dc1cee43265 100644
--- a/arch/alpha/kernel/pci.c
+++ b/arch/alpha/kernel/pci.c
@@ -195,7 +195,7 @@ pcibios_init(void)
 
 subsys_initcall(pcibios_init);
 
-char * __init
+char * __devinit
 pcibios_setup(char *str)
 {
         return str;
@@ -204,7 +204,7 @@ pcibios_setup(char *str)
 #ifdef ALPHA_RESTORE_SRM_SETUP
 static struct pdev_srm_saved_conf *srm_saved_configs;
 
-void __init
+void __devinit
 pdev_save_srm_config(struct pci_dev *dev)
 {
         struct pdev_srm_saved_conf *tmp;
@@ -247,14 +247,14 @@ pci_restore_srm_config(void)
 }
 #endif
 
-void __init
+void __devinit
 pcibios_fixup_resource(struct resource *res, struct resource *root)
 {
         res->start += root->start;
         res->end += root->start;
 }
 
-void __init
+void __devinit
 pcibios_fixup_device_resources(struct pci_dev *dev, struct pci_bus *bus)
 {
         /* Update device resources.  */
@@ -273,7 +273,7 @@ pcibios_fixup_device_resources(struct pci_dev *dev, struct pci_bus *bus)
         }
 }
 
-void __init
+void __devinit
 pcibios_fixup_bus(struct pci_bus *bus)
 {
         /* Propagate hose info into the subordinate devices.  */
diff --git a/arch/alpha/kernel/pci_iommu.c b/arch/alpha/kernel/pci_iommu.c
index 6b07f89a72c7..e1c470752ebc 100644
--- a/arch/alpha/kernel/pci_iommu.c
+++ b/arch/alpha/kernel/pci_iommu.c
@@ -58,7 +58,7 @@ size_for_memory(unsigned long max)
         return max;
 }
 
-struct pci_iommu_arena *
+struct pci_iommu_arena * __init
 iommu_arena_new_node(int nid, struct pci_controller *hose, dma_addr_t base,
                      unsigned long window_size, unsigned long align)
 {
@@ -117,7 +117,7 @@ iommu_arena_new_node(int nid, struct pci_controller *hose, dma_addr_t base,
         return arena;
 }
 
-struct pci_iommu_arena *
+struct pci_iommu_arena * __init
 iommu_arena_new(struct pci_controller *hose, dma_addr_t base,
                 unsigned long window_size, unsigned long align)
 {
diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c
index b28731437c31..0804b6abe203 100644
--- a/arch/alpha/kernel/smp.c
+++ b/arch/alpha/kernel/smp.c
@@ -358,7 +358,7 @@ secondary_cpu_start(int cpuid, struct task_struct *idle)
 /*
  * Bring one cpu online.
  */
-static int __devinit
+static int __cpuinit
 smp_boot_one_cpu(int cpuid)
 {
         struct task_struct *idle;
@@ -487,7 +487,7 @@ smp_prepare_boot_cpu(void)
 {
 }
 
-int __devinit
+int __cpuinit
 __cpu_up(unsigned int cpu)
 {
         smp_boot_one_cpu(cpu);
@@ -541,7 +541,7 @@ smp_percpu_timer_interrupt(struct pt_regs *regs)
         set_irq_regs(old_regs);
 }
 
-int __init
+int
 setup_profiling_timer(unsigned int multiplier)
 {
         return -EINVAL;
diff --git a/arch/alpha/kernel/vmlinux.lds.S b/arch/alpha/kernel/vmlinux.lds.S
index fe13daa5cb2c..7af07d3ad5f0 100644
--- a/arch/alpha/kernel/vmlinux.lds.S
+++ b/arch/alpha/kernel/vmlinux.lds.S
@@ -15,6 +15,7 @@ SECTIONS
 
   _text = .;                                    /* Text and read-only data */
   .text : { 
+        *(.text.head)
         TEXT_TEXT
         SCHED_TEXT
         LOCK_TEXT
diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index c3750c2c4113..c85598acb8fd 100644
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -430,22 +430,12 @@ void __init alternative_instructions(void)
  * And on the local CPU you need to be protected again NMI or MCE handlers
  * seeing an inconsistent instruction while you patch.
  */
-void __kprobes text_poke(void *oaddr, unsigned char *opcode, int len)
+void __kprobes text_poke(void *addr, unsigned char *opcode, int len)
 {
-        u8 *addr = oaddr;
-        if (!pte_write(*lookup_address((unsigned long)addr))) {
-                struct page *p[2] = { virt_to_page(addr), virt_to_page(addr+PAGE_SIZE) };
-                addr = vmap(p, 2, VM_MAP, PAGE_KERNEL);
-                if (!addr)
-                        return;
-                addr += ((unsigned long)oaddr) % PAGE_SIZE;
-        }
         memcpy(addr, opcode, len);
         sync_core();
         /* Not strictly needed, but can speed CPU recovery up. Ignore cross cacheline
            case. */
         if (cpu_has_clflush)
-                asm("clflush (%0) " :: "r" (oaddr) : "memory");
-        if (addr != oaddr)
-                vunmap(addr);
+                asm("clflush (%0) " :: "r" (addr) : "memory");
 }
diff --git a/arch/i386/kernel/cpu/cpufreq/Kconfig b/arch/i386/kernel/cpu/cpufreq/Kconfig
index 094118ba00da..d8c6f132dc7a 100644
--- a/arch/i386/kernel/cpu/cpufreq/Kconfig
+++ b/arch/i386/kernel/cpu/cpufreq/Kconfig
@@ -92,7 +92,7 @@ config X86_POWERNOW_K8
 config X86_POWERNOW_K8_ACPI
         bool "ACPI Support"
         select ACPI_PROCESSOR
-        depends on X86_POWERNOW_K8
+        depends on ACPI && X86_POWERNOW_K8
         default y
         help
           This provides access to the K8s Processor Performance States via ACPI.
diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c
index 1b1a1e66d099..4c4809f13cb1 100644
--- a/arch/i386/mm/init.c
+++ b/arch/i386/mm/init.c
@@ -800,9 +800,17 @@ void mark_rodata_ro(void)
         unsigned long start = PFN_ALIGN(_text);
         unsigned long size = PFN_ALIGN(_etext) - start;
 
-        change_page_attr(virt_to_page(start),
-                         size >> PAGE_SHIFT, PAGE_KERNEL_RX);
-        printk("Write protecting the kernel text: %luk\n", size >> 10);
+#ifndef CONFIG_KPROBES
+#ifdef CONFIG_HOTPLUG_CPU
+        /* It must still be possible to apply SMP alternatives. */
+        if (num_possible_cpus() <= 1)
+#endif
+        {
+                change_page_attr(virt_to_page(start),
+                                 size >> PAGE_SHIFT, PAGE_KERNEL_RX);
+                printk("Write protecting the kernel text: %luk\n", size >> 10);
+        }
+#endif
         start += size;
         size = (unsigned long)__end_rodata - start;
         change_page_attr(virt_to_page(start),
diff --git a/arch/ia64/kernel/cyclone.c b/arch/ia64/kernel/cyclone.c
index 2fd96d9062a1..790ef0d87e12 100644
--- a/arch/ia64/kernel/cyclone.c
+++ b/arch/ia64/kernel/cyclone.c
@@ -38,11 +38,11 @@ static struct clocksource clocksource_cyclone = {
 
 int __init init_cyclone_clock(void)
 {
-        u64* reg;
+        u64 __iomem *reg;
         u64 base;       /* saved cyclone base address */
         u64 offset;     /* offset from pageaddr to cyclone_timer register */
         int i;
-        u32* volatile cyclone_timer;    /* Cyclone MPMC0 register */
+        u32 __iomem *cyclone_timer;     /* Cyclone MPMC0 register */
 
         if (!use_cyclone)
                 return 0;
@@ -51,7 +51,7 @@ int __init init_cyclone_clock(void)
 
         /* find base address */
         offset = (CYCLONE_CBAR_ADDR);
-        reg = (u64*)ioremap_nocache(offset, sizeof(u64));
+        reg = ioremap_nocache(offset, sizeof(u64));
         if(!reg){
                 printk(KERN_ERR "Summit chipset: Could not find valid CBAR"
                                 " register.\n");
@@ -69,7 +69,7 @@ int __init init_cyclone_clock(void)
 
         /* setup PMCC */
         offset = (base + CYCLONE_PMCC_OFFSET);
-        reg = (u64*)ioremap_nocache(offset, sizeof(u64));
+        reg = ioremap_nocache(offset, sizeof(u64));
         if(!reg){
                 printk(KERN_ERR "Summit chipset: Could not find valid PMCC"
                                 " register.\n");
@@ -81,7 +81,7 @@ int __init init_cyclone_clock(void)
 
         /* setup MPCS */
         offset = (base + CYCLONE_MPCS_OFFSET);
-        reg = (u64*)ioremap_nocache(offset, sizeof(u64));
+        reg = ioremap_nocache(offset, sizeof(u64));
         if(!reg){
                 printk(KERN_ERR "Summit chipset: Could not find valid MPCS"
                                 " register.\n");
@@ -93,7 +93,7 @@ int __init init_cyclone_clock(void)
 
         /* map in cyclone_timer */
         offset = (base + CYCLONE_MPMC_OFFSET);
-        cyclone_timer = (u32*)ioremap_nocache(offset, sizeof(u32));
+        cyclone_timer = ioremap_nocache(offset, sizeof(u32));
         if(!cyclone_timer){
                 printk(KERN_ERR "Summit chipset: Could not find valid MPMC"
                                 " register.\n");
@@ -110,7 +110,7 @@ int __init init_cyclone_clock(void)
                         printk(KERN_ERR "Summit chipset: Counter not counting!"
                                         " DISABLED\n");
                         iounmap(cyclone_timer);
-                        cyclone_timer = 0;
+                        cyclone_timer = NULL;
                         use_cyclone = 0;
                         return -ENODEV;
                 }
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 627785c48ea9..6c0e9e2e1b82 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -52,7 +52,7 @@ static struct clocksource clocksource_itc = {
         .name           = "itc",
         .rating         = 350,
         .read           = itc_get_cycles,
-        .mask           = 0xffffffffffffffff,
+        .mask           = CLOCKSOURCE_MASK(64),
         .mult           = 0, /*to be caluclated*/
         .shift          = 16,
         .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
@@ -255,7 +255,7 @@ ia64_init_itm (void)
         }
 }
 
-static cycle_t itc_get_cycles()
+static cycle_t itc_get_cycles(void)
 {
         u64 lcycle, now, ret;
 
diff --git a/arch/m32r/kernel/setup_mappi.c b/arch/m32r/kernel/setup_mappi.c
index 6b2d77da0683..fe73c9ec611f 100644
--- a/arch/m32r/kernel/setup_mappi.c
+++ b/arch/m32r/kernel/setup_mappi.c
@@ -45,7 +45,8 @@ static void mask_and_ack_mappi(unsigned int irq)
 
 static void end_mappi_irq(unsigned int irq)
 {
-        enable_mappi_irq(irq);
+        if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
+                enable_mappi_irq(irq);
 }
 
 static unsigned int startup_mappi_irq(unsigned int irq)
@@ -88,7 +89,7 @@ void __init init_IRQ(void)
         irq_desc[M32R_IRQ_INT0].chip = &mappi_irq_type;
         irq_desc[M32R_IRQ_INT0].action = NULL;
         irq_desc[M32R_IRQ_INT0].depth = 1;
-        icu_data[M32R_IRQ_INT0].icucr = M32R_ICUCR_IEN|M32R_ICUCR_ISMOD10;
+        icu_data[M32R_IRQ_INT0].icucr = M32R_ICUCR_IEN|M32R_ICUCR_ISMOD11;
         disable_mappi_irq(M32R_IRQ_INT0);
 #endif /* CONFIG_M32R_NE2000 */
 
diff --git a/arch/m68knommu/kernel/setup.c b/arch/m68knommu/kernel/setup.c
index a5ac0d40fbec..3f86ade3a22a 100644
--- a/arch/m68knommu/kernel/setup.c
+++ b/arch/m68knommu/kernel/setup.c
@@ -42,8 +42,6 @@ EXPORT_SYMBOL(memory_end);
 
 char __initdata command_line[COMMAND_LINE_SIZE];
 
-void (*mach_trap_init)(void);
-
 /* machine dependent timer functions */
 void (*mach_sched_init)(irq_handler_t handler);
 void (*mach_tick)(void);
diff --git a/arch/m68knommu/platform/5206/config.c b/arch/m68knommu/platform/5206/config.c
index d265ed4e5afc..d0f2dc5cb5a1 100644
--- a/arch/m68knommu/platform/5206/config.c
+++ b/arch/m68knommu/platform/5206/config.c
@@ -28,7 +28,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -101,7 +100,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/5206e/config.c b/arch/m68knommu/platform/5206e/config.c
index 7fa5e8254c31..4ab614f1ecda 100644
--- a/arch/m68knommu/platform/5206e/config.c
+++ b/arch/m68knommu/platform/5206e/config.c
@@ -27,7 +27,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -107,7 +106,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/520x/config.c b/arch/m68knommu/platform/520x/config.c
index 85830f9882f3..a2c95bebd004 100644
--- a/arch/m68knommu/platform/520x/config.c
+++ b/arch/m68knommu/platform/520x/config.c
@@ -30,7 +30,6 @@ unsigned int dma_device_address[MAX_M68K_DMA_CHANNELS];
 void coldfire_pit_tick(void);
 void coldfire_pit_init(irq_handler_t handler);
 unsigned long coldfire_pit_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -51,7 +50,6 @@ void config_BSP(char *commandp, int size)
     mach_sched_init = coldfire_pit_init;
     mach_tick = coldfire_pit_tick;
     mach_gettimeoffset = coldfire_pit_offset;
-    mach_trap_init = coldfire_trap_init;
     mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/523x/config.c b/arch/m68knommu/platform/523x/config.c
index c0157e110035..0a3af05a434b 100644
--- a/arch/m68knommu/platform/523x/config.c
+++ b/arch/m68knommu/platform/523x/config.c
@@ -29,7 +29,6 @@
 void coldfire_pit_tick(void);
 void coldfire_pit_init(irq_handler_t handler);
 unsigned long coldfire_pit_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -66,7 +65,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_pit_init;
         mach_tick = coldfire_pit_tick;
         mach_gettimeoffset = coldfire_pit_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/5249/config.c b/arch/m68knommu/platform/5249/config.c
index 4cdeb719512d..dc2c362590c2 100644
--- a/arch/m68knommu/platform/5249/config.c
+++ b/arch/m68knommu/platform/5249/config.c
@@ -27,7 +27,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -99,7 +98,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/5272/config.c b/arch/m68knommu/platform/5272/config.c
index 609b10e4b9b9..1365a8300d5d 100644
--- a/arch/m68knommu/platform/5272/config.c
+++ b/arch/m68knommu/platform/5272/config.c
@@ -28,7 +28,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 extern unsigned int mcf_timervector;
@@ -132,7 +131,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/527x/config.c b/arch/m68knommu/platform/527x/config.c
index 126dac066482..1b820441419a 100644
--- a/arch/m68knommu/platform/527x/config.c
+++ b/arch/m68knommu/platform/527x/config.c
@@ -29,7 +29,6 @@
 void coldfire_pit_tick(void);
 void coldfire_pit_init(irq_handler_t handler);
 unsigned long coldfire_pit_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -66,7 +65,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_pit_init;
         mach_tick = coldfire_pit_tick;
         mach_gettimeoffset = coldfire_pit_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/528x/config.c b/arch/m68knommu/platform/528x/config.c
index aab1ef0c1f78..a089e9513699 100644
--- a/arch/m68knommu/platform/528x/config.c
+++ b/arch/m68knommu/platform/528x/config.c
@@ -29,7 +29,6 @@
 void coldfire_pit_tick(void);
 void coldfire_pit_init(irq_handler_t handler);
 unsigned long coldfire_pit_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 /***************************************************************************/
@@ -66,7 +65,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_pit_init;
         mach_tick = coldfire_pit_tick;
         mach_gettimeoffset = coldfire_pit_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/5307/config.c b/arch/m68knommu/platform/5307/config.c
index 1f10e941b87c..e3461619fd65 100644
--- a/arch/m68knommu/platform/5307/config.c
+++ b/arch/m68knommu/platform/5307/config.c
@@ -29,7 +29,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 extern unsigned int mcf_timervector;
@@ -126,7 +125,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 
 #ifdef MCF_BDM_DISABLE
diff --git a/arch/m68knommu/platform/5307/pit.c b/arch/m68knommu/platform/5307/pit.c
index aa15beeb36ca..e53c446d10e4 100644
--- a/arch/m68knommu/platform/5307/pit.c
+++ b/arch/m68knommu/platform/5307/pit.c
@@ -5,9 +5,8 @@
  *               hardware timer only exists in the Freescale ColdFire
  *               5270/5271, 5282 and other CPUs.
  *
- *      Copyright (C) 1999-2006, Greg Ungerer (gerg@snapgear.com)
+ *      Copyright (C) 1999-2007, Greg Ungerer (gerg@snapgear.com)
  *      Copyright (C) 2001-2004, SnapGear Inc. (www.snapgear.com)
- *
  */
 
 /***************************************************************************/
@@ -17,8 +16,8 @@
 #include <linux/param.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <asm/io.h>
-#include <asm/irq.h>
 #include <asm/coldfire.h>
 #include <asm/mcfpit.h>
 #include <asm/mcfsim.h>
@@ -43,13 +42,18 @@ void coldfire_pit_tick(void)
 
 /***************************************************************************/
 
+static struct irqaction coldfire_pit_irq = {
+        .name    = "timer",
+        .flags   = IRQF_DISABLED | IRQF_TIMER,
+};
+
 void coldfire_pit_init(irq_handler_t handler)
 {
         volatile unsigned char *icrp;
         volatile unsigned long *imrp;
 
-        request_irq(MCFINT_VECBASE + MCFINT_PIT1, handler, IRQF_DISABLED,
-                "ColdFire Timer", NULL);
+        coldfire_pit_irq.handler = handler;
+        setup_irq(MCFINT_VECBASE + MCFINT_PIT1, &coldfire_pit_irq);
 
         icrp = (volatile unsigned char *) (MCF_IPSBAR + MCFICM_INTC0 +
                 MCFINTC_ICR0 + MCFINT_PIT1);
diff --git a/arch/m68knommu/platform/5307/timers.c b/arch/m68knommu/platform/5307/timers.c
index fb66eadd5896..64bd0ff9029e 100644
--- a/arch/m68knommu/platform/5307/timers.c
+++ b/arch/m68knommu/platform/5307/timers.c
@@ -3,7 +3,7 @@
 /*
  *      timers.c -- generic ColdFire hardware timer support.
  *
- *      Copyright (C) 1999-2006, Greg Ungerer (gerg@snapgear.com)
+ *      Copyright (C) 1999-2007, Greg Ungerer (gerg@snapgear.com)
  */
 
 /***************************************************************************/
@@ -13,8 +13,8 @@
 #include <linux/param.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/irq.h>
 #include <asm/io.h>
-#include <asm/irq.h>
 #include <asm/traps.h>
 #include <asm/machdep.h>
 #include <asm/coldfire.h>
@@ -62,17 +62,24 @@ void coldfire_tick(void)
 
 /***************************************************************************/
 
+static struct irqaction coldfire_timer_irq = {
+        .name    = "timer",
+        .flags   = IRQF_DISABLED | IRQF_TIMER,
+};
+
 static int ticks_per_intr;
 
 void coldfire_timer_init(irq_handler_t handler)
 {
+        coldfire_timer_irq.handler = handler;
+        setup_irq(mcf_timervector, &coldfire_timer_irq);
+
         __raw_writew(MCFTIMER_TMR_DISABLE, TA(MCFTIMER_TMR));
         ticks_per_intr = (MCF_BUSCLK / 16) / HZ;
         __raw_writetrr(ticks_per_intr - 1, TA(MCFTIMER_TRR));
         __raw_writew(MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 |
                 MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, TA(MCFTIMER_TMR));
 
-        request_irq(mcf_timervector, handler, IRQF_DISABLED, "timer", NULL);
         mcf_settimericr(1, mcf_timerlevel);
 
 #ifdef CONFIG_HIGHPROFILE
diff --git a/arch/m68knommu/platform/532x/config.c b/arch/m68knommu/platform/532x/config.c
index dc39c466e33f..b32c6425f821 100644
--- a/arch/m68knommu/platform/532x/config.c
+++ b/arch/m68knommu/platform/532x/config.c
@@ -37,7 +37,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 extern unsigned int mcf_timervector;
@@ -108,7 +107,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 
 #ifdef MCF_BDM_DISABLE
diff --git a/arch/m68knommu/platform/5407/config.c b/arch/m68knommu/platform/5407/config.c
index fde417fdd650..e692536817d8 100644
--- a/arch/m68knommu/platform/5407/config.c
+++ b/arch/m68knommu/platform/5407/config.c
@@ -28,7 +28,6 @@
 void coldfire_tick(void);
 void coldfire_timer_init(irq_handler_t handler);
 unsigned long coldfire_timer_offset(void);
-void coldfire_trap_init(void);
 void coldfire_reset(void);
 
 extern unsigned int mcf_timervector;
@@ -112,7 +111,6 @@ void config_BSP(char *commandp, int size)
         mach_sched_init = coldfire_timer_init;
         mach_tick = coldfire_tick;
         mach_gettimeoffset = coldfire_timer_offset;
-        mach_trap_init = coldfire_trap_init;
         mach_reset = coldfire_reset;
 }
 
diff --git a/arch/m68knommu/platform/68328/timers.c b/arch/m68knommu/platform/68328/timers.c
index ef067f4c3cd4..0396476f955d 100644
--- a/arch/m68knommu/platform/68328/timers.c
+++ b/arch/m68knommu/platform/68328/timers.c
@@ -18,10 +18,10 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <asm/setup.h>
 #include <asm/system.h>
 #include <asm/pgtable.h>
-#include <asm/irq.h>
 #include <asm/machdep.h>
 #include <asm/MC68VZ328.h>
 
@@ -53,14 +53,19 @@
 
 /***************************************************************************/
 
+static struct irqaction m68328_timer_irq = {
+        .name    = "timer",
+        .flags   = IRQF_DISABLED | IRQF_TIMER,
+};
+
 void m68328_timer_init(irq_handler_t timer_routine)
 {
         /* disable timer 1 */
         TCTL = 0;
 
         /* set ISR */
-        if (request_irq(TMR_IRQ_NUM, timer_routine, IRQ_FLG_LOCK, "timer", NULL)) 
-                panic("Unable to attach timer interrupt\n");
+        m68328_timer_irq.handler = timer_routine;
+        setup_irq(TMR_IRQ_NUM, &m68328_timer_irq);
 
         /* Restart mode, Enable int, Set clock source */
         TCTL = TCTL_OM | TCTL_IRQEN | CLOCK_SOURCE;
diff --git a/arch/m68knommu/platform/68360/config.c b/arch/m68knommu/platform/68360/config.c
index 4ff13bd51ffd..155b72fe2607 100644
--- a/arch/m68knommu/platform/68360/config.c
+++ b/arch/m68knommu/platform/68360/config.c
@@ -17,11 +17,11 @@
 #include <linux/tty.h>
 #include <linux/console.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 
 #include <asm/setup.h>
 #include <asm/system.h>
 #include <asm/pgtable.h>
-#include <asm/irq.h>
 #include <asm/machdep.h>
 #include <asm/m68360.h>
 
@@ -51,11 +51,15 @@ extern unsigned long int system_clock; //In kernel setup.c
 
 extern void config_M68360_irq(void);
 
+static struct irqaction m68360_timer_irq = {
+        .name    = "timer",
+        .flags   = IRQF_DISABLED | IRQF_TIMER,
+};
+
 void BSP_sched_init(irq_handler_t timer_routine)
 {
   unsigned char prescaler;
   unsigned short tgcr_save;
-  int return_value;
 
 #if 0
   /* Restart mode, Enable int, 32KHz, Enable timer */
@@ -86,10 +90,8 @@ void BSP_sched_init(irq_handler_t timer_routine)
   pquicc->timer_ter1 = 0x0003; /* clear timer events */
 
   /* enable timer 1 interrupt in CIMR */
-//  request_irq(IRQ_MACHSPEC | CPMVEC_TIMER1, timer_routine, IRQ_FLG_LOCK, "timer", NULL);
-  //return_value = request_irq( CPMVEC_TIMER1, timer_routine, IRQ_FLG_LOCK, "timer", NULL);
-  return_value = request_irq(CPMVEC_TIMER1 , timer_routine, IRQ_FLG_LOCK,
-          "Timer", NULL);
+  m68360_timer_irq.handler = timer_routine;
+  setup_irq(CPMVEC_TIMER1, &m68360_timer_irq);
 
   /* Start timer 1: */
   tgcr_save = (pquicc->timer_tgcr & 0xfff0) | 0x0001;
diff --git a/arch/sparc64/kernel/viohs.c b/arch/sparc64/kernel/viohs.c
index 09126fc338ba..708fa1705fbe 100644
--- a/arch/sparc64/kernel/viohs.c
+++ b/arch/sparc64/kernel/viohs.c
@@ -702,7 +702,7 @@ u32 vio_send_sid(struct vio_driver_state *vio)
 }
 EXPORT_SYMBOL(vio_send_sid);
 
-extern int vio_ldc_alloc(struct vio_driver_state *vio,
+int vio_ldc_alloc(struct vio_driver_state *vio,
                          struct ldc_channel_config *base_cfg,
                          void *event_arg)
 {
diff --git a/arch/x86_64/ia32/ia32_binfmt.c b/arch/x86_64/ia32/ia32_binfmt.c
index b70f3e7cf06c..dffd2ac72747 100644
--- a/arch/x86_64/ia32/ia32_binfmt.c
+++ b/arch/x86_64/ia32/ia32_binfmt.c
@@ -41,8 +41,9 @@ int sysctl_vsyscall32 = 1;
 #undef ARCH_DLINFO
 #define ARCH_DLINFO do {  \
         if (sysctl_vsyscall32) { \
-        NEW_AUX_ENT(AT_SYSINFO, (u32)(u64)VSYSCALL32_VSYSCALL); \
-        NEW_AUX_ENT(AT_SYSINFO_EHDR, VSYSCALL32_BASE);    \
+                current->mm->context.vdso = (void *)VSYSCALL32_BASE;    \
+                NEW_AUX_ENT(AT_SYSINFO, (u32)(u64)VSYSCALL32_VSYSCALL); \
+                NEW_AUX_ENT(AT_SYSINFO_EHDR, VSYSCALL32_BASE);    \
         }       \
 } while(0)
 
diff --git a/arch/x86_64/ia32/syscall32.c b/arch/x86_64/ia32/syscall32.c
index fc4419ff0355..15013bac181c 100644
--- a/arch/x86_64/ia32/syscall32.c
+++ b/arch/x86_64/ia32/syscall32.c
@@ -49,14 +49,6 @@ int syscall32_setup_pages(struct linux_binprm *bprm, int exstack)
         return ret;
 }
 
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
-        if (vma->vm_start == VSYSCALL32_BASE &&
-            vma->vm_mm && vma->vm_mm->task_size == IA32_PAGE_OFFSET)
-                return "[vdso]";
-        return NULL;
-}
-
 static int __init init_syscall32(void)
 { 
         char *syscall32_page = (void *)get_zeroed_page(GFP_KERNEL);
diff --git a/arch/x86_64/kernel/tce.c b/arch/x86_64/kernel/tce.c
index 3aeae2fa2e24..821527e7faa3 100644
--- a/arch/x86_64/kernel/tce.c
+++ b/arch/x86_64/kernel/tce.c
@@ -165,7 +165,7 @@ done:
         return ret;
 }
 
-void* alloc_tce_table(void)
+void * __init alloc_tce_table(void)
 {
         unsigned int size;
 
@@ -175,7 +175,7 @@ void* alloc_tce_table(void)
         return __alloc_bootmem_low(size, size, 0);
 }
 
-void free_tce_table(void *tbl)
+void __init free_tce_table(void *tbl)
 {
         unsigned int size;
 
diff --git a/arch/x86_64/kernel/tsc.c b/arch/x86_64/kernel/tsc.c
index 9b76b03d0600..2a59bde663f2 100644
--- a/arch/x86_64/kernel/tsc.c
+++ b/arch/x86_64/kernel/tsc.c
@@ -118,8 +118,6 @@ core_initcall(cpufreq_tsc);
 
 #endif
 
-static int tsc_unstable = 0;
-
 /*
  * Make an educated guess if the TSC is trustworthy and synchronized
  * over all CPUs.
diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index 38f5d6368006..458893b376f8 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -600,6 +600,16 @@ void mark_rodata_ro(void)
 {
         unsigned long start = (unsigned long)_stext, end;
 
+#ifdef CONFIG_HOTPLUG_CPU
+        /* It must still be possible to apply SMP alternatives. */
+        if (num_possible_cpus() > 1)
+                start = (unsigned long)_etext;
+#endif
+
+#ifdef CONFIG_KPROBES
+        start = (unsigned long)__start_rodata;
+#endif
+        
         end = (unsigned long)__end_rodata;
         start = (start + PAGE_SIZE - 1) & PAGE_MASK;
         end &= PAGE_MASK;
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 251344cb29ae..22b401b2e088 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -11,9 +11,6 @@ menuconfig ACPI
         depends on PCI
         depends on PM
         select PNP
-        # for sleep
-        select HOTPLUG_CPU if X86 && SMP
-        select SUSPEND_SMP if X86 && SMP
         default y
         ---help---
           Advanced Configuration and Power Interface (ACPI) support for 
diff --git a/drivers/base/power/shutdown.c b/drivers/base/power/shutdown.c
index a47ee1b70d20..56e8eaaac012 100644
--- a/drivers/base/power/shutdown.c
+++ b/drivers/base/power/shutdown.c
@@ -44,7 +44,5 @@ void device_shutdown(void)
                         dev->driver->shutdown(dev);
                 }
         }
-
-        sysdev_shutdown();
 }
 
diff --git a/drivers/block/lguest_blk.c b/drivers/block/lguest_blk.c
index 5b79d0724171..93e3c4001bf5 100644
--- a/drivers/block/lguest_blk.c
+++ b/drivers/block/lguest_blk.c
@@ -1,6 +1,12 @@
-/* A simple block driver for lguest.
+/*D:400
+ * The Guest block driver
  *
- * Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
+ * This is a simple block driver, which appears as /dev/lgba, lgbb, lgbc etc.
+ * The mechanism is simple: we place the information about the request in the
+ * device page, then use SEND_DMA (containing the data for a write, or an empty
+ * "ping" DMA for a read).
+ :*/
+/* Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,27 +31,50 @@
 
 static char next_block_index = 'a';
 
+/*D:420 Here is the structure which holds all the information we need about
+ * each Guest block device.
+ *
+ * I'm sure at this stage, you're wondering "hey, where was the adventure I was
+ * promised?" and thinking "Rusty sucks, I shall say nasty things about him on
+ * my blog".  I think Real adventures have boring bits, too, and you're in the
+ * middle of one.  But it gets better.  Just not quite yet. */
 struct blockdev
 {
+        /* The block queue infrastructure wants a spinlock: it is held while it
+         * calls our block request function.  We grab it in our interrupt
+         * handler so the responses don't mess with new requests. */
         spinlock_t lock;
 
-        /* The disk structure for the kernel. */
+        /* The disk structure registered with kernel. */
         struct gendisk *disk;
 
-        /* The major number for this disk. */
+        /* The major device number for this disk, and the interrupt.  We only
+         * really keep them here for completeness; we'd need them if we
+         * supported device unplugging. */
         int major;
         int irq;
 
+        /* The physical address of this device's memory page */
         unsigned long phys_addr;
-        /* The mapped block page. */
+        /* The mapped memory page for convenient acces. */
         struct lguest_block_page *lb_page;
 
-        /* We only have a single request outstanding at a time. */
+        /* We only have a single request outstanding at a time: this is it. */
         struct lguest_dma dma;
         struct request *req;
 };
 
-/* Jens gave me this nice helper to end all chunks of a request. */
+/*D:495 We originally used end_request() throughout the driver, but it turns
+ * out that end_request() is deprecated, and doesn't actually end the request
+ * (which seems like a good reason to deprecate it!).  It simply ends the first
+ * bio.  So if we had 3 bios in a "struct request" we would do all 3,
+ * end_request(), do 2, end_request(), do 1 and end_request(): twice as much
+ * work as we needed to do.
+ *
+ * This reinforced to me that I do not understand the block layer.
+ *
+ * Nonetheless, Jens Axboe gave me this nice helper to end all chunks of a
+ * request.  This improved disk speed by 130%. */
 static void end_entire_request(struct request *req, int uptodate)
 {
         if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
@@ -55,30 +84,62 @@ static void end_entire_request(struct request *req, int uptodate)
         end_that_request_last(req, uptodate);
 }
 
+/* I'm told there are only two stories in the world worth telling: love and
+ * hate.  So there used to be a love scene here like this:
+ *
+ *  Launcher:   We could make beautiful I/O together, you and I.
+ *  Guest:      My, that's a big disk!
+ *
+ * Unfortunately, it was just too raunchy for our otherwise-gentle tale. */
+
+/*D:490 This is the interrupt handler, called when a block read or write has
+ * been completed for us. */
 static irqreturn_t lgb_irq(int irq, void *_bd)
 {
+        /* We handed our "struct blockdev" as the argument to request_irq(), so
+         * it is passed through to us here.  This tells us which device we're
+         * dealing with in case we have more than one. */
         struct blockdev *bd = _bd;
         unsigned long flags;
 
+        /* We weren't doing anything?  Strange, but could happen if we shared
+         * interrupts (we don't!). */
         if (!bd->req) {
                 pr_debug("No work!\n");
                 return IRQ_NONE;
         }
 
+        /* Not done yet?  That's equally strange. */
         if (!bd->lb_page->result) {
                 pr_debug("No result!\n");
                 return IRQ_NONE;
         }
 
+        /* We have to grab the lock before ending the request. */
         spin_lock_irqsave(&bd->lock, flags);
+        /* "result" is 1 for success, 2 for failure: end_entire_request() wants
+         * to know whether this succeeded or not. */
         end_entire_request(bd->req, bd->lb_page->result == 1);
+        /* Clear out request, it's done. */
         bd->req = NULL;
+        /* Reset incoming DMA for next time. */
         bd->dma.used_len = 0;
+        /* Ready for more reads or writes */
         blk_start_queue(bd->disk->queue);
         spin_unlock_irqrestore(&bd->lock, flags);
+
+        /* The interrupt was for us, we dealt with it. */
         return IRQ_HANDLED;
 }
 
+/*D:480 The block layer's "struct request" contains a number of "struct bio"s,
+ * each of which contains "struct bio_vec"s, each of which contains a page, an
+ * offset and a length.
+ *
+ * Fortunately there are iterators to help us walk through the "struct
+ * request".  Even more fortunately, there were plenty of places to steal the
+ * code from.  We pack the "struct request" into our "struct lguest_dma" and
+ * return the total length. */
 static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
 {
         unsigned int i = 0, idx, len = 0;
@@ -87,8 +148,13 @@ static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
         rq_for_each_bio(bio, req) {
                 struct bio_vec *bvec;
                 bio_for_each_segment(bvec, bio, idx) {
+                        /* We told the block layer not to give us too many. */
                         BUG_ON(i == LGUEST_MAX_DMA_SECTIONS);
+                        /* If we had a zero-length segment, it would look like
+                         * the end of the data referred to by the "struct
+                         * lguest_dma", so make sure that doesn't happen. */
                         BUG_ON(!bvec->bv_len);
+                        /* Convert page & offset to a physical address */
                         dma->addr[i] = page_to_phys(bvec->bv_page)
                                 + bvec->bv_offset;
                         dma->len[i] = bvec->bv_len;
@@ -96,26 +162,39 @@ static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
                         i++;
                 }
         }
+        /* If the array isn't full, we mark the end with a 0 length */
         if (i < LGUEST_MAX_DMA_SECTIONS)
                 dma->len[i] = 0;
         return len;
 }
 
+/* This creates an empty DMA, useful for prodding the Host without sending data
+ * (ie. when we want to do a read) */
 static void empty_dma(struct lguest_dma *dma)
 {
         dma->len[0] = 0;
 }
 
+/*D:470 Setting up a request is fairly easy: */
 static void setup_req(struct blockdev *bd,
                       int type, struct request *req, struct lguest_dma *dma)
 {
+        /* The type is 1 (write) or 0 (read). */
         bd->lb_page->type = type;
+        /* The sector on disk where the read or write starts. */
         bd->lb_page->sector = req->sector;
+        /* The result is initialized to 0 (unfinished). */
         bd->lb_page->result = 0;
+        /* The current request (so we can end it in the interrupt handler). */
         bd->req = req;
+        /* The number of bytes: returned as a side-effect of req_to_dma(),
+         * which packs the block layer's "struct request" into our "struct
+         * lguest_dma" */
         bd->lb_page->bytes = req_to_dma(req, dma);
 }
 
+/*D:450 Write is pretty straightforward: we pack the request into a "struct
+ * lguest_dma", then use SEND_DMA to send the request. */
 static void do_write(struct blockdev *bd, struct request *req)
 {
         struct lguest_dma send;
@@ -126,6 +205,9 @@ static void do_write(struct blockdev *bd, struct request *req)
         lguest_send_dma(bd->phys_addr, &send);
 }
 
+/* Read is similar to write, except we pack the request into our receive
+ * "struct lguest_dma" and send through an empty DMA just to tell the Host that
+ * there's a request pending. */
 static void do_read(struct blockdev *bd, struct request *req)
 {
         struct lguest_dma ping;
@@ -137,21 +219,30 @@ static void do_read(struct blockdev *bd, struct request *req)
         lguest_send_dma(bd->phys_addr, &ping);
 }
 
+/*D:440 This where requests come in: we get handed the request queue and are
+ * expected to pull a "struct request" off it until we've finished them or
+ * we're waiting for a reply: */
 static void do_lgb_request(struct request_queue *q)
 {
         struct blockdev *bd;
         struct request *req;
 
 again:
+        /* This sometimes returns NULL even on the very first time around.  I
+         * wonder if it's something to do with letting elves handle the request
+         * queue... */
         req = elv_next_request(q);
         if (!req)
                 return;
 
+        /* We attached the struct blockdev to the disk: get it back */
         bd = req->rq_disk->private_data;
-        /* Sometimes we get repeated requests after blk_stop_queue. */
+        /* Sometimes we get repeated requests after blk_stop_queue(), but we
+         * can only handle one at a time. */
         if (bd->req)
                 return;
 
+        /* We only do reads and writes: no tricky business! */
         if (!blk_fs_request(req)) {
                 pr_debug("Got non-command 0x%08x\n", req->cmd_type);
                 req->errors++;
@@ -164,20 +255,31 @@ again:
         else
                 do_read(bd, req);
 
-        /* Wait for interrupt to tell us it's done. */
+        /* We've put out the request, so stop any more coming in until we get
+         * an interrupt, which takes us to lgb_irq() to re-enable the queue. */
         blk_stop_queue(q);
 }
 
+/*D:430 This is the "struct block_device_operations" we attach to the disk at
+ * the end of lguestblk_probe().  It doesn't seem to want much. */
 static struct block_device_operations lguestblk_fops = {
         .owner = THIS_MODULE,
 };
 
+/*D:425 Setting up a disk device seems to involve a lot of code.  I'm not sure
+ * quite why.  I do know that the IDE code sent two or three of the maintainers
+ * insane, perhaps this is the fringe of the same disease?
+ *
+ * As in the console code, the probe function gets handed the generic
+ * lguest_device from lguest_bus.c: */
 static int lguestblk_probe(struct lguest_device *lgdev)
 {
         struct blockdev *bd;
         int err;
         int irqflags = IRQF_SHARED;
 
+        /* First we allocate our own "struct blockdev" and initialize the easy
+         * fields. */
         bd = kmalloc(sizeof(*bd), GFP_KERNEL);
         if (!bd)
                 return -ENOMEM;
@@ -187,59 +289,100 @@ static int lguestblk_probe(struct lguest_device *lgdev)
         bd->req = NULL;
         bd->dma.used_len = 0;
         bd->dma.len[0] = 0;
+        /* The descriptor in the lguest_devices array provided by the Host
+         * gives the Guest the physical page number of the device's page. */
         bd->phys_addr = (lguest_devices[lgdev->index].pfn << PAGE_SHIFT);
 
+        /* We use lguest_map() to get a pointer to the device page */
         bd->lb_page = lguest_map(bd->phys_addr, 1);
         if (!bd->lb_page) {
                 err = -ENOMEM;
                 goto out_free_bd;
         }
 
+        /* We need a major device number: 0 means "assign one dynamically". */
         bd->major = register_blkdev(0, "lguestblk");
         if (bd->major < 0) {
                 err = bd->major;
                 goto out_unmap;
         }
 
+        /* This allocates a "struct gendisk" where we pack all the information
+         * about the disk which the rest of Linux sees.  We ask for one minor
+         * number; I do wonder if we should be asking for more. */
         bd->disk = alloc_disk(1);
         if (!bd->disk) {
                 err = -ENOMEM;
                 goto out_unregister_blkdev;
         }
 
+        /* Every disk needs a queue for requests to come in: we set up the
+         * queue with a callback function (the core of our driver) and the lock
+         * to use. */
         bd->disk->queue = blk_init_queue(do_lgb_request, &bd->lock);
         if (!bd->disk->queue) {
                 err = -ENOMEM;
                 goto out_put_disk;
         }
 
-        /* We can only handle a certain number of sg entries */
+        /* We can only handle a certain number of pointers in our SEND_DMA
+         * call, so we set that with blk_queue_max_hw_segments().  This is not
+         * to be confused with blk_queue_max_phys_segments() of course!  I
+         * know, who could possibly confuse the two?
+         *
+         * Well, it's simple to tell them apart: this one seems to work and the
+         * other one didn't. */
         blk_queue_max_hw_segments(bd->disk->queue, LGUEST_MAX_DMA_SECTIONS);
-        /* Buffers must not cross page boundaries */
+
+        /* Due to technical limitations of our Host (and simple coding) we
+         * can't have a single buffer which crosses a page boundary.  Tell it
+         * here.  This means that our maximum request size is 16
+         * (LGUEST_MAX_DMA_SECTIONS) pages. */
         blk_queue_segment_boundary(bd->disk->queue, PAGE_SIZE-1);
 
+        /* We name our disk: this becomes the device name when udev does its
+         * magic thing and creates the device node, such as /dev/lgba.
+         * next_block_index is a global which starts at 'a'.  Unfortunately
+         * this simple increment logic means that the 27th disk will be called
+         * "/dev/lgb{".  In that case, I recommend having at least 29 disks, so
+         * your /dev directory will be balanced. */
         sprintf(bd->disk->disk_name, "lgb%c", next_block_index++);
+
+        /* We look to the device descriptor again to see if this device's
+         * interrupts are expected to be random.  If they are, we tell the irq
+         * subsystem.  At the moment this bit is always set. */
         if (lguest_devices[lgdev->index].features & LGUEST_DEVICE_F_RANDOMNESS)
                 irqflags |= IRQF_SAMPLE_RANDOM;
+
+        /* Now we have the name and irqflags, we can request the interrupt; we
+         * give it the "struct blockdev" we have set up to pass to lgb_irq()
+         * when there is an interrupt. */
         err = request_irq(bd->irq, lgb_irq, irqflags, bd->disk->disk_name, bd);
         if (err)
                 goto out_cleanup_queue;
 
+        /* We bind our one-entry DMA pool to the key for this block device so
+         * the Host can reply to our requests.  The key is equal to the
+         * physical address of the device's page, which is conveniently
+         * unique. */
         err = lguest_bind_dma(bd->phys_addr, &bd->dma, 1, bd->irq);
         if (err)
                 goto out_free_irq;
 
+        /* We finish our disk initialization and add the disk to the system. */
         bd->disk->major = bd->major;
         bd->disk->first_minor = 0;
         bd->disk->private_data = bd;
         bd->disk->fops = &lguestblk_fops;
-        /* This is initialized to the disk size by the other end. */
+        /* This is initialized to the disk size by the Launcher. */
         set_capacity(bd->disk, bd->lb_page->num_sectors);
         add_disk(bd->disk);
 
         printk(KERN_INFO "%s: device %i at major %d\n",
                bd->disk->disk_name, lgdev->index, bd->major);
 
+        /* We don't need to keep the "struct blockdev" around, but if we ever
+         * implemented device removal, we'd need this. */
         lgdev->private = bd;
         return 0;
 
@@ -258,6 +401,8 @@ out_free_bd:
         return err;
 }
 
+/*D:410 The boilerplate code for registering the lguest block driver is just
+ * like the console: */
 static struct lguest_driver lguestblk_drv = {
         .name = "lguestblk",
         .owner = THIS_MODULE,
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index acdbcdc3e457..b391776e5bf3 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -130,6 +130,7 @@ config ROCKETPORT
 config CYCLADES
         tristate "Cyclades async mux support"
         depends on SERIAL_NONSTANDARD && (PCI || ISA)
+        select FW_LOADER
         ---help---
           This driver supports Cyclades Z and Y multiserial boards.
           You would need something like this to connect more than two modems to
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index 9a2694e5f8b9..77bf4aa217a8 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -73,7 +73,7 @@ static struct clocksource clocksource_hpet = {
         .name           = "hpet",
         .rating         = 250,
         .read           = read_hpet,
-        .mask           = 0xffffffffffffffff,
+        .mask           = CLOCKSOURCE_MASK(64),
         .mult           = 0, /*to be caluclated*/
         .shift          = 10,
         .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
diff --git a/drivers/char/hvc_lguest.c b/drivers/char/hvc_lguest.c
index e7b889e404a7..feeccbaec438 100644
--- a/drivers/char/hvc_lguest.c
+++ b/drivers/char/hvc_lguest.c
@@ -1,6 +1,22 @@
-/* Simple console for lguest.
+/*D:300
+ * The Guest console driver
  *
- * Copyright (C) 2006 Rusty Russell, IBM Corporation
+ * This is a trivial console driver: we use lguest's DMA mechanism to send
+ * bytes out, and register a DMA buffer to receive bytes in.  It is assumed to
+ * be present and available from the very beginning of boot.
+ *
+ * Writing console drivers is one of the few remaining Dark Arts in Linux.
+ * Fortunately for us, the path of virtual consoles has been well-trodden by
+ * the PowerPC folks, who wrote "hvc_console.c" to generically support any
+ * virtual console.  We use that infrastructure which only requires us to write
+ * the basic put_chars and get_chars functions and call the right register
+ * functions.
+ :*/
+
+/*M:002 The console can be flooded: while the Guest is processing input the
+ * Host can send more.  Buffering in the Host could alleviate this, but it is a
+ * difficult problem in general. :*/
+/* Copyright (C) 2006 Rusty Russell, IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -21,49 +37,81 @@
 #include <linux/lguest_bus.h>
 #include "hvc_console.h"
 
+/*D:340 This is our single console input buffer, with associated "struct
+ * lguest_dma" referring to it.  Note the 0-terminated length array, and the
+ * use of physical address for the buffer itself. */
 static char inbuf[256];
 static struct lguest_dma cons_input = { .used_len = 0,
                                         .addr[0] = __pa(inbuf),
                                         .len[0] = sizeof(inbuf),
                                         .len[1] = 0 };
 
+/*D:310 The put_chars() callback is pretty straightforward.
+ *
+ * First we put the pointer and length in a "struct lguest_dma": we only have
+ * one pointer, so we set the second length to 0.  Then we use SEND_DMA to send
+ * the data to (Host) buffers attached to the console key.  Usually a device's
+ * key is a physical address within the device's memory, but because the
+ * console device doesn't have any associated physical memory, we use the
+ * LGUEST_CONSOLE_DMA_KEY constant (aka 0). */
 static int put_chars(u32 vtermno, const char *buf, int count)
 {
         struct lguest_dma dma;
 
-        /* FIXME: what if it's over a page boundary? */
+        /* FIXME: DMA buffers in a "struct lguest_dma" are not allowed
+         * to go over page boundaries.  This never seems to happen,
+         * but if it did we'd need to fix this code. */
         dma.len[0] = count;
         dma.len[1] = 0;
         dma.addr[0] = __pa(buf);
 
         lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
+        /* We're expected to return the amount of data we wrote: all of it. */
         return count;
 }
 
+/*D:350 get_chars() is the callback from the hvc_console infrastructure when
+ * an interrupt is received.
+ *
+ * Firstly we see if our buffer has been filled: if not, we return.  The rest
+ * of the code deals with the fact that the hvc_console() infrastructure only
+ * asks us for 16 bytes at a time.  We keep a "cons_offset" variable for
+ * partially-read buffers. */
 static int get_chars(u32 vtermno, char *buf, int count)
 {
         static int cons_offset;
 
+        /* Nothing left to see here... */
         if (!cons_input.used_len)
                 return 0;
 
+        /* You want more than we have to give?  Well, try wanting less! */
         if (cons_input.used_len - cons_offset < count)
                 count = cons_input.used_len - cons_offset;
 
+        /* Copy across to their buffer and increment offset. */
         memcpy(buf, inbuf + cons_offset, count);
         cons_offset += count;
+
+        /* Finished?  Zero offset, and reset cons_input so Host will use it
+         * again. */
         if (cons_offset == cons_input.used_len) {
                 cons_offset = 0;
                 cons_input.used_len = 0;
         }
         return count;
 }
+/*:*/
 
 static struct hv_ops lguest_cons = {
         .get_chars = get_chars,
         .put_chars = put_chars,
 };
 
+/*D:320 Console drivers are initialized very early so boot messages can go
+ * out.  At this stage, the console is output-only.  Our driver checks we're a
+ * Guest, and if so hands hvc_instantiate() the console number (0), priority
+ * (0), and the struct hv_ops containing the put_chars() function. */
 static int __init cons_init(void)
 {
         if (strcmp(paravirt_ops.name, "lguest") != 0)
@@ -73,21 +121,46 @@ static int __init cons_init(void)
 }
 console_initcall(cons_init);
 
+/*D:370 To set up and manage our virtual console, we call hvc_alloc() and
+ * stash the result in the private pointer of the "struct lguest_device".
+ * Since we never remove the console device we never need this pointer again,
+ * but using ->private is considered good form, and you never know who's going
+ * to copy your driver.
+ *
+ * Once the console is set up, we bind our input buffer ready for input. */
 static int lguestcons_probe(struct lguest_device *lgdev)
 {
         int err;
 
+        /* The first argument of hvc_alloc() is the virtual console number, so
+         * we use zero.  The second argument is the interrupt number.
+         *
+         * The third argument is a "struct hv_ops" containing the put_chars()
+         * and get_chars() pointers.  The final argument is the output buffer
+         * size: we use 256 and expect the Host to have room for us to send
+         * that much. */
         lgdev->private = hvc_alloc(0, lgdev_irq(lgdev), &lguest_cons, 256);
         if (IS_ERR(lgdev->private))
                 return PTR_ERR(lgdev->private);
 
+        /* We bind a single DMA buffer at key LGUEST_CONSOLE_DMA_KEY.
+         * "cons_input" is that statically-initialized global DMA buffer we saw
+         * above, and we also give the interrupt we want. */
         err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY, &cons_input, 1,
                               lgdev_irq(lgdev));
         if (err)
                 printk("lguest console: failed to bind buffer.\n");
         return err;
 }
+/* Note the use of lgdev_irq() for the interrupt number.  We tell hvc_alloc()
+ * to expect input when this interrupt is triggered, and then tell
+ * lguest_bind_dma() that is the interrupt to send us when input comes in. */
 
+/*D:360 From now on the console driver follows standard Guest driver form:
+ * register_lguest_driver() registers the device type and probe function, and
+ * the probe function sets up the device.
+ *
+ * The standard "struct lguest_driver": */
 static struct lguest_driver lguestcons_drv = {
         .name = "lguestcons",
         .owner = THIS_MODULE,
@@ -95,6 +168,7 @@ static struct lguest_driver lguestcons_drv = {
         .probe = lguestcons_probe,
 };
 
+/* The standard init function */
 static int __init hvc_lguest_init(void)
 {
         return register_lguest_driver(&lguestcons_drv);
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 1724c41d2414..98b6b4fb4257 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -8,7 +8,7 @@ menuconfig EDAC
         bool "EDAC - error detection and reporting (EXPERIMENTAL)"
         depends on HAS_IOMEM
         depends on EXPERIMENTAL
-        depends on X86 || MIPS || PPC
+        depends on X86 || PPC
         help
           EDAC is designed to report errors in the core system.
           These are low-level errors that are reported in the CPU or
@@ -126,7 +126,7 @@ config EDAC_I5000
 config EDAC_PASEMI
         tristate "PA Semi PWRficient"
         depends on EDAC_MM_EDAC && PCI
-        depends on PPC
+        depends on PPC_PASEMI
         help
           Support for error detection and correction on PA Semi
           PWRficient.
diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c
index 4471be362599..063a1bffe38b 100644
--- a/drivers/edac/edac_mc.c
+++ b/drivers/edac/edac_mc.c
@@ -214,6 +214,13 @@ void edac_mc_free(struct mem_ctl_info *mci)
 }
 EXPORT_SYMBOL_GPL(edac_mc_free);
 
+
+/*
+ * find_mci_by_dev
+ *
+ *      scan list of controllers looking for the one that manages
+ *      the 'dev' device
+ */
 static struct mem_ctl_info *find_mci_by_dev(struct device *dev)
 {
         struct mem_ctl_info *mci;
@@ -268,12 +275,6 @@ static void edac_mc_workq_function(struct work_struct *work_req)
         if (edac_mc_assert_error_check_and_clear() && (mci->edac_check != NULL))
                 mci->edac_check(mci);
 
-        /*
-         * FIXME: temp place holder for PCI checks,
-         * goes away when we break out PCI
-         */
-        edac_pci_do_parity_check();
-
         mutex_unlock(&mem_ctls_mutex);
 
         /* Reschedule */
@@ -314,36 +315,55 @@ static void edac_mc_workq_teardown(struct mem_ctl_info *mci)
 {
         int status;
 
-        /* if not running POLL, leave now */
-        if (mci->op_state == OP_RUNNING_POLL) {
-                status = cancel_delayed_work(&mci->work);
-                if (status == 0) {
-                        debugf0("%s() not canceled, flush the queue\n",
-                                __func__);
+        status = cancel_delayed_work(&mci->work);
+        if (status == 0) {
+                debugf0("%s() not canceled, flush the queue\n",
+                        __func__);
 
-                        /* workq instance might be running, wait for it */
-                        flush_workqueue(edac_workqueue);
-                }
+                /* workq instance might be running, wait for it */
+                flush_workqueue(edac_workqueue);
         }
 }
 
 /*
- * edac_reset_delay_period
+ * edac_mc_reset_delay_period(unsigned long value)
+ *
+ *      user space has updated our poll period value, need to
+ *      reset our workq delays
  */
-static void edac_reset_delay_period(struct mem_ctl_info *mci, unsigned long value)
+void edac_mc_reset_delay_period(int value)
 {
-        /* cancel the current workq request */
-        edac_mc_workq_teardown(mci);
+        struct mem_ctl_info *mci;
+        struct list_head *item;
 
-        /* lock the list of devices for the new setup */
         mutex_lock(&mem_ctls_mutex);
 
-        /* restart the workq request, with new delay value */
-        edac_mc_workq_setup(mci, value);
+        /* scan the list and turn off all workq timers, doing so under lock
+         */
+        list_for_each(item, &mc_devices) {
+                mci = list_entry(item, struct mem_ctl_info, link);
+
+                if (mci->op_state == OP_RUNNING_POLL)
+                        cancel_delayed_work(&mci->work);
+        }
+
+        mutex_unlock(&mem_ctls_mutex);
+
+
+        /* re-walk the list, and reset the poll delay */
+        mutex_lock(&mem_ctls_mutex);
+
+        list_for_each(item, &mc_devices) {
+                mci = list_entry(item, struct mem_ctl_info, link);
+
+                edac_mc_workq_setup(mci, (unsigned long) value);
+        }
 
         mutex_unlock(&mem_ctls_mutex);
 }
 
+
+
 /* Return 0 on success, 1 on failure.
  * Before calling this function, caller must
  * assign a unique value to mci->mc_idx.
diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index cd090b0677a7..4a0576bd06fc 100644
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -122,6 +122,23 @@ static ssize_t memctrl_int_store(void *ptr, const char *buffer, size_t count)
         return count;
 }
 
+/*
+ * mc poll_msec time value
+ */
+static ssize_t poll_msec_int_store(void *ptr, const char *buffer, size_t count)
+{
+        int *value = (int *)ptr;
+
+        if (isdigit(*buffer)) {
+                *value = simple_strtoul(buffer, NULL, 0);
+
+                /* notify edac_mc engine to reset the poll period */
+                edac_mc_reset_delay_period(*value);
+        }
+
+        return count;
+}
+
 
 /* EDAC sysfs CSROW data structures and methods
  */
@@ -704,7 +721,7 @@ MEMCTRL_ATTR(edac_mc_log_ce,
         S_IRUGO | S_IWUSR, memctrl_int_show, memctrl_int_store);
 
 MEMCTRL_ATTR(edac_mc_poll_msec,
-        S_IRUGO | S_IWUSR, memctrl_int_show, memctrl_int_store);
+        S_IRUGO | S_IWUSR, memctrl_int_show, poll_msec_int_store);
 
 /* Base Attributes of the memory ECC object */
 static struct memctrl_dev_attribute *memctrl_attr[] = {
diff --git a/drivers/edac/edac_module.h b/drivers/edac/edac_module.h
index a2134dfc3cc6..cbc419c8ebc1 100644
--- a/drivers/edac/edac_module.h
+++ b/drivers/edac/edac_module.h
@@ -52,6 +52,8 @@ extern void edac_device_workq_setup(struct edac_device_ctl_info *edac_dev,
 extern void edac_device_workq_teardown(struct edac_device_ctl_info *edac_dev);
 extern void edac_device_reset_delay_period(struct edac_device_ctl_info
                                            *edac_dev, unsigned long value);
+extern void edac_mc_reset_delay_period(int value);
+
 extern void *edac_align_ptr(void *ptr, unsigned size);
 
 /*
@@ -64,6 +66,10 @@ extern int edac_sysfs_pci_setup(void);
 extern void edac_sysfs_pci_teardown(void);
 extern int edac_pci_get_check_errors(void);
 extern int edac_pci_get_poll_msec(void);
+extern void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci);
+extern void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg);
+extern void edac_pci_handle_npe(struct edac_pci_ctl_info *pci,
+                                const char *msg);
 #else                           /* CONFIG_PCI */
 /* pre-process these away */
 #define edac_pci_do_parity_check()
@@ -72,6 +78,8 @@ extern int edac_pci_get_poll_msec(void);
 #define edac_sysfs_pci_teardown()
 #define edac_pci_get_check_errors()
 #define edac_pci_get_poll_msec()
+#define edac_pci_handle_pe()
+#define edac_pci_handle_npe()
 #endif                          /* CONFIG_PCI */
 
 #endif                          /* __EDAC_MODULE_H__ */
diff --git a/drivers/edac/edac_pci.c b/drivers/edac/edac_pci.c
index d9cd5e048cee..5dee9f50414b 100644
--- a/drivers/edac/edac_pci.c
+++ b/drivers/edac/edac_pci.c
@@ -31,20 +31,12 @@
 static DEFINE_MUTEX(edac_pci_ctls_mutex);
 static struct list_head edac_pci_list = LIST_HEAD_INIT(edac_pci_list);
 
-static inline void edac_lock_pci_list(void)
-{
-        mutex_lock(&edac_pci_ctls_mutex);
-}
-
-static inline void edac_unlock_pci_list(void)
-{
-        mutex_unlock(&edac_pci_ctls_mutex);
-}
-
 /*
- * The alloc() and free() functions for the 'edac_pci' control info
- * structure. The chip driver will allocate one of these for each
- * edac_pci it is going to control/register with the EDAC CORE.
+ * edac_pci_alloc_ctl_info
+ *
+ *      The alloc() function for the 'edac_pci' control info
+ *      structure. The chip driver will allocate one of these for each
+ *      edac_pci it is going to control/register with the EDAC CORE.
  */
 struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
                                                 const char *edac_pci_name)
@@ -53,47 +45,59 @@ struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
         void *pvt;
         unsigned int size;
 
+        debugf1("%s()\n", __func__);
+
         pci = (struct edac_pci_ctl_info *)0;
         pvt = edac_align_ptr(&pci[1], sz_pvt);
         size = ((unsigned long)pvt) + sz_pvt;
 
-        if ((pci = kzalloc(size, GFP_KERNEL)) == NULL)
+        /* Alloc the needed control struct memory */
+        pci = kzalloc(size, GFP_KERNEL);
+        if (pci  == NULL)
                 return NULL;
 
+        /* Now much private space */
         pvt = sz_pvt ? ((char *)pci) + ((unsigned long)pvt) : NULL;
 
         pci->pvt_info = pvt;
-
         pci->op_state = OP_ALLOC;
 
         snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name);
 
         return pci;
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);
 
 /*
  * edac_pci_free_ctl_info()
- *      frees the memory allocated by edac_pci_alloc_ctl_info() function
+ *
+ *      Last action on the pci control structure.
+ *
+ *      call the remove sysfs informaton, which will unregister
+ *      this control struct's kobj. When that kobj's ref count
+ *      goes to zero, its release function will be call and then
+ *      kfree() the memory.
  */
 void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
 {
-        kfree(pci);
-}
+        debugf1("%s()\n", __func__);
 
+        edac_pci_remove_sysfs(pci);
+}
 EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);
 
 /*
  * find_edac_pci_by_dev()
  *      scans the edac_pci list for a specific 'struct device *'
+ *
+ *      return NULL if not found, or return control struct pointer
  */
 static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev)
 {
         struct edac_pci_ctl_info *pci;
         struct list_head *item;
 
-        debugf3("%s()\n", __func__);
+        debugf1("%s()\n", __func__);
 
         list_for_each(item, &edac_pci_list) {
                 pci = list_entry(item, struct edac_pci_ctl_info, link);
@@ -118,10 +122,13 @@ static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
         struct list_head *item, *insert_before;
         struct edac_pci_ctl_info *rover;
 
+        debugf1("%s()\n", __func__);
+
         insert_before = &edac_pci_list;
 
         /* Determine if already on the list */
-        if (unlikely((rover = find_edac_pci_by_dev(pci->dev)) != NULL))
+        rover = find_edac_pci_by_dev(pci->dev);
+        if (unlikely(rover != NULL))
                 goto fail0;
 
         /* Insert in ascending order by 'pci_idx', so find position */
@@ -157,6 +164,8 @@ fail1:
 
 /*
  * complete_edac_pci_list_del
+ *
+ *      RCU completion callback to indicate item is deleted
  */
 static void complete_edac_pci_list_del(struct rcu_head *head)
 {
@@ -169,6 +178,8 @@ static void complete_edac_pci_list_del(struct rcu_head *head)
 
 /*
  * del_edac_pci_from_global_list
+ *
+ *      remove the PCI control struct from the global list
  */
 static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
 {
@@ -207,35 +218,52 @@ struct edac_pci_ctl_info *edac_pci_find(int idx)
 
         return NULL;
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_find);
 
 /*
  * edac_pci_workq_function()
- *      performs the operation scheduled by a workq request
+ *
+ *      periodic function that performs the operation
+ *      scheduled by a workq request, for a given PCI control struct
  */
 static void edac_pci_workq_function(struct work_struct *work_req)
 {
         struct delayed_work *d_work = (struct delayed_work *)work_req;
         struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
+        int msec;
+        unsigned long delay;
 
-        edac_lock_pci_list();
+        debugf3("%s() checking\n", __func__);
 
-        if ((pci->op_state == OP_RUNNING_POLL) &&
-                (pci->edac_check != NULL) && (edac_pci_get_check_errors()))
-                pci->edac_check(pci);
+        mutex_lock(&edac_pci_ctls_mutex);
 
-        edac_unlock_pci_list();
+        if (pci->op_state == OP_RUNNING_POLL) {
+                /* we might be in POLL mode, but there may NOT be a poll func
+                 */
+                if ((pci->edac_check != NULL) && edac_pci_get_check_errors())
+                        pci->edac_check(pci);
+
+                /* if we are on a one second period, then use round */
+                msec = edac_pci_get_poll_msec();
+                if (msec == 1000)
+                        delay = round_jiffies(msecs_to_jiffies(msec));
+                else
+                        delay = msecs_to_jiffies(msec);
+
+                /* Reschedule only if we are in POLL mode */
+                queue_delayed_work(edac_workqueue, &pci->work, delay);
+        }
 
-        /* Reschedule */
-        queue_delayed_work(edac_workqueue, &pci->work,
-                        msecs_to_jiffies(edac_pci_get_poll_msec()));
+        mutex_unlock(&edac_pci_ctls_mutex);
 }
 
 /*
  * edac_pci_workq_setup()
  *      initialize a workq item for this edac_pci instance
  *      passing in the new delay period in msec
+ *
+ *      locking model:
+ *              called when 'edac_pci_ctls_mutex' is locked
  */
 static void edac_pci_workq_setup(struct edac_pci_ctl_info *pci,
                                  unsigned int msec)
@@ -255,6 +283,8 @@ static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci)
 {
         int status;
 
+        debugf0("%s()\n", __func__);
+
         status = cancel_delayed_work(&pci->work);
         if (status == 0)
                 flush_workqueue(edac_workqueue);
@@ -262,19 +292,25 @@ static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci)
 
 /*
  * edac_pci_reset_delay_period
+ *
+ *      called with a new period value for the workq period
+ *      a) stop current workq timer
+ *      b) restart workq timer with new value
  */
 void edac_pci_reset_delay_period(struct edac_pci_ctl_info *pci,
                                  unsigned long value)
 {
-        edac_lock_pci_list();
+        debugf0("%s()\n", __func__);
 
         edac_pci_workq_teardown(pci);
 
+        /* need to lock for the setup */
+        mutex_lock(&edac_pci_ctls_mutex);
+
         edac_pci_workq_setup(pci, value);
 
-        edac_unlock_pci_list();
+        mutex_unlock(&edac_pci_ctls_mutex);
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_reset_delay_period);
 
 /*
@@ -294,14 +330,13 @@ int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
         debugf0("%s()\n", __func__);
 
         pci->pci_idx = edac_idx;
+        pci->start_time = jiffies;
 
-        edac_lock_pci_list();
+        mutex_lock(&edac_pci_ctls_mutex);
 
         if (add_edac_pci_to_global_list(pci))
                 goto fail0;
 
-        pci->start_time = jiffies;
-
         if (edac_pci_create_sysfs(pci)) {
                 edac_pci_printk(pci, KERN_WARNING,
                                 "failed to create sysfs pci\n");
@@ -323,16 +358,16 @@ int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
                         pci->ctl_name,
                         dev_name(pci), edac_op_state_to_string(pci->op_state));
 
-        edac_unlock_pci_list();
+        mutex_unlock(&edac_pci_ctls_mutex);
         return 0;
 
+        /* error unwind stack */
 fail1:
         del_edac_pci_from_global_list(pci);
 fail0:
-        edac_unlock_pci_list();
+        mutex_unlock(&edac_pci_ctls_mutex);
         return 1;
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_add_device);
 
 /*
@@ -354,22 +389,25 @@ struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
 
         debugf0("%s()\n", __func__);
 
-        edac_lock_pci_list();
+        mutex_lock(&edac_pci_ctls_mutex);
 
-        if ((pci = find_edac_pci_by_dev(dev)) == NULL) {
-                edac_unlock_pci_list();
+        /* ensure the control struct is on the global list
+         * if not, then leave
+         */
+        pci = find_edac_pci_by_dev(dev);
+        if (pci  == NULL) {
+                mutex_unlock(&edac_pci_ctls_mutex);
                 return NULL;
         }
 
         pci->op_state = OP_OFFLINE;
 
-        edac_pci_workq_teardown(pci);
-
-        edac_pci_remove_sysfs(pci);
-
         del_edac_pci_from_global_list(pci);
 
-        edac_unlock_pci_list();
+        mutex_unlock(&edac_pci_ctls_mutex);
+
+        /* stop the workq timer */
+        edac_pci_workq_teardown(pci);
 
         edac_printk(KERN_INFO, EDAC_PCI,
                 "Removed device %d for %s %s: DEV %s\n",
@@ -377,14 +415,20 @@ struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
 
         return pci;
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_del_device);
 
+/*
+ * edac_pci_generic_check
+ *
+ *      a Generic parity check API
+ */
 void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
 {
+        debugf4("%s()\n", __func__);
         edac_pci_do_parity_check();
 }
 
+/* free running instance index counter */
 static int edac_pci_idx;
 #define EDAC_PCI_GENCTL_NAME    "EDAC PCI controller"
 
@@ -392,6 +436,17 @@ struct edac_pci_gen_data {
         int edac_idx;
 };
 
+/*
+ * edac_pci_create_generic_ctl
+ *
+ *      A generic constructor for a PCI parity polling device
+ *      Some systems have more than one domain of PCI busses.
+ *      For systems with one domain, then this API will
+ *      provide for a generic poller.
+ *
+ *      This routine calls the edac_pci_alloc_ctl_info() for
+ *      the generic device, with default values
+ */
 struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
                                                 const char *mod_name)
 {
@@ -421,13 +476,18 @@ struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
 
         return pci;
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);
 
+/*
+ * edac_pci_release_generic_ctl
+ *
+ *      The release function of a generic EDAC PCI polling device
+ */
 void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
 {
+        debugf0("%s() pci mod=%s\n", __func__, pci->mod_name);
+
         edac_pci_del_device(pci->dev);
         edac_pci_free_ctl_info(pci);
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);
diff --git a/drivers/edac/edac_pci_sysfs.c b/drivers/edac/edac_pci_sysfs.c
index fac94cae2c3d..69f5dddabddf 100644
--- a/drivers/edac/edac_pci_sysfs.c
+++ b/drivers/edac/edac_pci_sysfs.c
@@ -13,22 +13,25 @@
 #include "edac_core.h"
 #include "edac_module.h"
 
+/* Turn off this whole feature if PCI is not configured */
 #ifdef CONFIG_PCI
 
 #define EDAC_PCI_SYMLINK        "device"
 
-static int check_pci_errors;    /* default YES check PCI parity */
-static int edac_pci_panic_on_pe;        /* default no panic on PCI Parity */
-static int edac_pci_log_pe = 1; /* log PCI parity errors */
+/* data variables exported via sysfs */
+static int check_pci_errors;            /* default NO check PCI parity */
+static int edac_pci_panic_on_pe;        /* default NO panic on PCI Parity */
+static int edac_pci_log_pe = 1;         /* log PCI parity errors */
 static int edac_pci_log_npe = 1;        /* log PCI non-parity error errors */
+static int edac_pci_poll_msec = 1000;   /* one second workq period */
+
 static atomic_t pci_parity_count = ATOMIC_INIT(0);
 static atomic_t pci_nonparity_count = ATOMIC_INIT(0);
-static int edac_pci_poll_msec = 1000;
 
-static struct kobject edac_pci_kobj;    /* /sys/devices/system/edac/pci */
-static struct completion edac_pci_kobj_complete;
+static struct kobject edac_pci_top_main_kobj;
 static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0);
 
+/* getter functions for the data variables */
 int edac_pci_get_check_errors(void)
 {
         return check_pci_errors;
@@ -74,17 +77,22 @@ static void edac_pci_instance_release(struct kobject *kobj)
 {
         struct edac_pci_ctl_info *pci;
 
-        debugf1("%s()\n", __func__);
+        debugf0("%s()\n", __func__);
 
+        /* Form pointer to containing struct, the pci control struct */
         pci = to_instance(kobj);
-        complete(&pci->kobj_complete);
+
+        /* decrement reference count on top main kobj */
+        kobject_put(&edac_pci_top_main_kobj);
+
+        kfree(pci);     /* Free the control struct */
 }
 
 /* instance specific attribute structure */
 struct instance_attribute {
         struct attribute attr;
-         ssize_t(*show) (struct edac_pci_ctl_info *, char *);
-         ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t);
+        ssize_t(*show) (struct edac_pci_ctl_info *, char *);
+        ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t);
 };
 
 /* Function to 'show' fields from the edac_pci 'instance' structure */
@@ -112,6 +120,7 @@ static ssize_t edac_pci_instance_store(struct kobject *kobj,
         return -EIO;
 }
 
+/* fs_ops table */
 static struct sysfs_ops pci_instance_ops = {
         .show = edac_pci_instance_show,
         .store = edac_pci_instance_store
@@ -134,48 +143,82 @@ static struct instance_attribute *pci_instance_attr[] = {
         NULL
 };
 
-/* the ktype for pci instance */
+/* the ktype for a pci instance */
 static struct kobj_type ktype_pci_instance = {
         .release = edac_pci_instance_release,
         .sysfs_ops = &pci_instance_ops,
         .default_attrs = (struct attribute **)pci_instance_attr,
 };
 
+/*
+ * edac_pci_create_instance_kobj
+ *
+ *      construct one EDAC PCI instance's kobject for use
+ */
 static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
 {
+        struct kobject *main_kobj;
         int err;
 
-        pci->kobj.parent = &edac_pci_kobj;
+        debugf0("%s()\n", __func__);
+
+        /* Set the parent and the instance's ktype */
+        pci->kobj.parent = &edac_pci_top_main_kobj;
         pci->kobj.ktype = &ktype_pci_instance;
 
         err = kobject_set_name(&pci->kobj, "pci%d", idx);
         if (err)
                 return err;
 
+        /* First bump the ref count on the top main kobj, which will
+         * track the number of PCI instances we have, and thus nest
+         * properly on keeping the module loaded
+         */
+        main_kobj = kobject_get(&edac_pci_top_main_kobj);
+        if (!main_kobj) {
+                err = -ENODEV;
+                goto error_out;
+        }
+
+        /* And now register this new kobject under the main kobj */
         err = kobject_register(&pci->kobj);
         if (err != 0) {
                 debugf2("%s() failed to register instance pci%d\n",
                         __func__, idx);
-                return err;
+                kobject_put(&edac_pci_top_main_kobj);
+                goto error_out;
         }
 
         debugf1("%s() Register instance 'pci%d' kobject\n", __func__, idx);
 
         return 0;
+
+        /* Error unwind statck */
+error_out:
+        return err;
 }
 
-static void
-edac_pci_delete_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
+/*
+ * edac_pci_unregister_sysfs_instance_kobj
+ *
+ *      unregister the kobj for the EDAC PCI instance
+ */
+void edac_pci_unregister_sysfs_instance_kobj(struct edac_pci_ctl_info *pci)
 {
-        init_completion(&pci->kobj_complete);
+        debugf0("%s()\n", __func__);
+
+        /* Unregister the instance kobject and allow its release
+         * function release the main reference count and then
+         * kfree the memory
+         */
         kobject_unregister(&pci->kobj);
-        wait_for_completion(&pci->kobj_complete);
 }
 
 /***************************** EDAC PCI sysfs root **********************/
 #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj)
 #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr)
 
+/* simple show/store functions for attributes */
 static ssize_t edac_pci_int_show(void *ptr, char *buffer)
 {
         int *value = ptr;
@@ -267,118 +310,189 @@ static struct edac_pci_dev_attribute *edac_pci_attr[] = {
         NULL,
 };
 
-/* No memory to release */
-static void edac_pci_release(struct kobject *kobj)
+/*
+ * edac_pci_release_main_kobj
+ *
+ *      This release function is called when the reference count to the
+ *      passed kobj goes to zero.
+ *
+ *      This kobj is the 'main' kobject that EDAC PCI instances
+ *      link to, and thus provide for proper nesting counts
+ */
+static void edac_pci_release_main_kobj(struct kobject *kobj)
 {
-        struct edac_pci_ctl_info *pci;
 
-        pci = to_edacpci(kobj);
+        debugf0("%s() here to module_put(THIS_MODULE)\n", __func__);
 
-        debugf1("%s()\n", __func__);
-        complete(&pci->kobj_complete);
+        /* last reference to top EDAC PCI kobject has been removed,
+         * NOW release our ref count on the core module
+         */
+        module_put(THIS_MODULE);
 }
 
-static struct kobj_type ktype_edac_pci = {
-        .release = edac_pci_release,
+/* ktype struct for the EDAC PCI main kobj */
+static struct kobj_type ktype_edac_pci_main_kobj = {
+        .release = edac_pci_release_main_kobj,
         .sysfs_ops = &edac_pci_sysfs_ops,
         .default_attrs = (struct attribute **)edac_pci_attr,
 };
 
 /**
- * edac_sysfs_pci_setup()
+ * edac_pci_main_kobj_setup()
  *
  *      setup the sysfs for EDAC PCI attributes
  *      assumes edac_class has already been initialized
  */
-int edac_pci_register_main_kobj(void)
+int edac_pci_main_kobj_setup(void)
 {
         int err;
         struct sysdev_class *edac_class;
 
-        debugf1("%s()\n", __func__);
+        debugf0("%s()\n", __func__);
+
+        /* check and count if we have already created the main kobject */
+        if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1)
+                return 0;
 
+        /* First time, so create the main kobject and its
+         * controls and atributes
+         */
         edac_class = edac_get_edac_class();
         if (edac_class == NULL) {
                 debugf1("%s() no edac_class\n", __func__);
-                return -ENODEV;
+                err = -ENODEV;
+                goto decrement_count_fail;
         }
 
-        edac_pci_kobj.ktype = &ktype_edac_pci;
+        /* Need the kobject hook ups, and name setting */
+        edac_pci_top_main_kobj.ktype = &ktype_edac_pci_main_kobj;
+        edac_pci_top_main_kobj.parent = &edac_class->kset.kobj;
 
-        edac_pci_kobj.parent = &edac_class->kset.kobj;
-
-        err = kobject_set_name(&edac_pci_kobj, "pci");
+        err = kobject_set_name(&edac_pci_top_main_kobj, "pci");
         if (err)
-                return err;
+                goto decrement_count_fail;
+
+        /* Bump the reference count on this module to ensure the
+         * modules isn't unloaded until we deconstruct the top
+         * level main kobj for EDAC PCI
+         */
+        if (!try_module_get(THIS_MODULE)) {
+                debugf1("%s() try_module_get() failed\n", __func__);
+                err = -ENODEV;
+                goto decrement_count_fail;
+        }
 
         /* Instanstiate the pci object */
         /* FIXME: maybe new sysdev_create_subdir() */
-        err = kobject_register(&edac_pci_kobj);
-
+        err = kobject_register(&edac_pci_top_main_kobj);
         if (err) {
                 debugf1("Failed to register '.../edac/pci'\n");
-                return err;
+                goto kobject_register_fail;
         }
 
+        /* At this point, to 'release' the top level kobject
+         * for EDAC PCI, then edac_pci_main_kobj_teardown()
+         * must be used, for resources to be cleaned up properly
+         */
         debugf1("Registered '.../edac/pci' kobject\n");
 
         return 0;
+
+        /* Error unwind statck */
+kobject_register_fail:
+        module_put(THIS_MODULE);
+
+decrement_count_fail:
+        /* if are on this error exit, nothing to tear down */
+        atomic_dec(&edac_pci_sysfs_refcount);
+
+        return err;
 }
 
 /*
- * edac_pci_unregister_main_kobj()
+ * edac_pci_main_kobj_teardown()
  *
- *      perform the sysfs teardown for the PCI attributes
+ *      if no longer linked (needed) remove the top level EDAC PCI
+ *      kobject with its controls and attributes
  */
-void edac_pci_unregister_main_kobj(void)
+static void edac_pci_main_kobj_teardown(void)
 {
         debugf0("%s()\n", __func__);
-        init_completion(&edac_pci_kobj_complete);
-        kobject_unregister(&edac_pci_kobj);
-        wait_for_completion(&edac_pci_kobj_complete);
+
+        /* Decrement the count and only if no more controller instances
+         * are connected perform the unregisteration of the top level
+         * main kobj
+         */
+        if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
+                debugf0("%s() called kobject_unregister on main kobj\n",
+                        __func__);
+                kobject_unregister(&edac_pci_top_main_kobj);
+        }
 }
 
+/*
+ *
+ * edac_pci_create_sysfs
+ *
+ *      Create the controls/attributes for the specified EDAC PCI device
+ */
 int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
 {
         int err;
         struct kobject *edac_kobj = &pci->kobj;
 
-        if (atomic_inc_return(&edac_pci_sysfs_refcount) == 1) {
-                err = edac_pci_register_main_kobj();
-                if (err) {
-                        atomic_dec(&edac_pci_sysfs_refcount);
-                        return err;
-                }
-        }
+        debugf0("%s() idx=%d\n", __func__, pci->pci_idx);
 
-        err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
-        if (err) {
-                if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0)
-                        edac_pci_unregister_main_kobj();
-        }
+        /* create the top main EDAC PCI kobject, IF needed */
+        err = edac_pci_main_kobj_setup();
+        if (err)
+                return err;
 
-        debugf0("%s() idx=%d\n", __func__, pci->pci_idx);
+        /* Create this instance's kobject under the MAIN kobject */
+        err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
+        if (err)
+                goto unregister_cleanup;
 
         err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
         if (err) {
                 debugf0("%s() sysfs_create_link() returned err= %d\n",
                         __func__, err);
-                return err;
+                goto symlink_fail;
         }
 
         return 0;
+
+        /* Error unwind stack */
+symlink_fail:
+        edac_pci_unregister_sysfs_instance_kobj(pci);
+
+unregister_cleanup:
+        edac_pci_main_kobj_teardown();
+
+        return err;
 }
 
+/*
+ * edac_pci_remove_sysfs
+ *
+ *      remove the controls and attributes for this EDAC PCI device
+ */
 void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
 {
-        debugf0("%s()\n", __func__);
-
-        edac_pci_delete_instance_kobj(pci, pci->pci_idx);
+        debugf0("%s() index=%d\n", __func__, pci->pci_idx);
 
+        /* Remove the symlink */
         sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);
 
-        if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0)
-                edac_pci_unregister_main_kobj();
+        /* remove this PCI instance's sysfs entries */
+        edac_pci_unregister_sysfs_instance_kobj(pci);
+
+        /* Call the main unregister function, which will determine
+         * if this 'pci' is the last instance.
+         * If it is, the main kobject will be unregistered as a result
+         */
+        debugf0("%s() calling edac_pci_main_kobj_teardown()\n", __func__);
+        edac_pci_main_kobj_teardown();
 }
 
 /************************ PCI error handling *************************/
@@ -414,13 +528,14 @@ static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
         return status;
 }
 
-typedef void (*pci_parity_check_fn_t) (struct pci_dev * dev);
 
 /* Clear any PCI parity errors logged by this device. */
 static void edac_pci_dev_parity_clear(struct pci_dev *dev)
 {
         u8 header_type;
 
+        debugf0("%s()\n", __func__);
+
         get_pci_parity_status(dev, 0);
 
         /* read the device TYPE, looking for bridges */
@@ -433,17 +548,28 @@ static void edac_pci_dev_parity_clear(struct pci_dev *dev)
 /*
  *  PCI Parity polling
  *
+ *      Fucntion to retrieve the current parity status
+ *      and decode it
+ *
  */
 static void edac_pci_dev_parity_test(struct pci_dev *dev)
 {
+        unsigned long flags;
         u16 status;
         u8 header_type;
 
-        /* read the STATUS register on this device
-         */
+        /* stop any interrupts until we can acquire the status */
+        local_irq_save(flags);
+
+        /* read the STATUS register on this device */
         status = get_pci_parity_status(dev, 0);
 
-        debugf2("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
+        /* read the device TYPE, looking for bridges */
+        pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
+
+        local_irq_restore(flags);
+
+        debugf4("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
 
         /* check the status reg for errors */
         if (status) {
@@ -471,16 +597,14 @@ static void edac_pci_dev_parity_test(struct pci_dev *dev)
                 }
         }
 
-        /* read the device TYPE, looking for bridges */
-        pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 
-        debugf2("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id);
+        debugf4("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id);
 
         if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) {
                 /* On bridges, need to examine secondary status register  */
                 status = get_pci_parity_status(dev, 1);
 
-                debugf2("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
+                debugf4("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
 
                 /* check the secondary status reg for errors */
                 if (status) {
@@ -510,9 +634,12 @@ static void edac_pci_dev_parity_test(struct pci_dev *dev)
         }
 }
 
+/* reduce some complexity in definition of the iterator */
+typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
+
 /*
  * pci_dev parity list iterator
- *      Scan the PCI device list for one iteration, looking for SERRORs
+ *      Scan the PCI device list for one pass, looking for SERRORs
  *      Master Parity ERRORS or Parity ERRORs on primary or secondary devices
  */
 static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
@@ -535,22 +662,22 @@ static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
  */
 void edac_pci_do_parity_check(void)
 {
-        unsigned long flags;
         int before_count;
 
         debugf3("%s()\n", __func__);
 
+        /* if policy has PCI check off, leave now */
         if (!check_pci_errors)
                 return;
 
         before_count = atomic_read(&pci_parity_count);
 
         /* scan all PCI devices looking for a Parity Error on devices and
-         * bridges
+         * bridges.
+         * The iterator calls pci_get_device() which might sleep, thus
+         * we cannot disable interrupts in this scan.
          */
-        local_irq_save(flags);
         edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
-        local_irq_restore(flags);
 
         /* Only if operator has selected panic on PCI Error */
         if (edac_pci_get_panic_on_pe()) {
@@ -560,6 +687,12 @@ void edac_pci_do_parity_check(void)
         }
 }
 
+/*
+ * edac_pci_clear_parity_errors
+ *
+ *      function to perform an iteration over the PCI devices
+ *      and clearn their current status
+ */
 void edac_pci_clear_parity_errors(void)
 {
         /* Clear any PCI bus parity errors that devices initially have logged
@@ -567,6 +700,12 @@ void edac_pci_clear_parity_errors(void)
          */
         edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
 }
+
+/*
+ * edac_pci_handle_pe
+ *
+ *      Called to handle a PARITY ERROR event
+ */
 void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
 {
 
@@ -584,9 +723,14 @@ void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
          */
         edac_pci_do_parity_check();
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_handle_pe);
 
+
+/*
+ * edac_pci_handle_npe
+ *
+ *      Called to handle a NON-PARITY ERROR event
+ */
 void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
 {
 
@@ -604,7 +748,6 @@ void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
          */
         edac_pci_do_parity_check();
 }
-
 EXPORT_SYMBOL_GPL(edac_pci_handle_npe);
 
 /*
diff --git a/drivers/edac/i3000_edac.c b/drivers/edac/i3000_edac.c
index 0ecfdc432f87..e895f9f887ab 100644
--- a/drivers/edac/i3000_edac.c
+++ b/drivers/edac/i3000_edac.c
@@ -275,7 +275,7 @@ static int i3000_probe1(struct pci_dev *pdev, int dev_idx)
         unsigned char *c0dra = dra, *c1dra = &dra[I3000_RANKS_PER_CHANNEL / 2];
         unsigned char *c0drb = drb, *c1drb = &drb[I3000_RANKS_PER_CHANNEL];
         unsigned long mchbar;
-        void *window;
+        void __iomem *window;
 
         debugf0("MC: %s()\n", __func__);
 
diff --git a/drivers/i2c/chips/ds1682.c b/drivers/i2c/chips/ds1682.c
index 5879f0f25495..9e94542c18a2 100644
--- a/drivers/i2c/chips/ds1682.c
+++ b/drivers/i2c/chips/ds1682.c
@@ -75,7 +75,8 @@ static ssize_t ds1682_show(struct device *dev, struct device_attribute *attr,
         /* Special case: the 32 bit regs are time values with 1/4s
          * resolution, scale them up to milliseconds */
         if (sattr->nr == 4)
-                return sprintf(buf, "%llu\n", ((u64) le32_to_cpu(val)) * 250);
+                return sprintf(buf, "%llu\n",
+                        ((unsigned long long)le32_to_cpu(val)) * 250);
 
         /* Format the output string and return # of bytes */
         return sprintf(buf, "%li\n", (long)le32_to_cpu(val));
diff --git a/drivers/ide/pci/scc_pata.c b/drivers/ide/pci/scc_pata.c
index f668d235e6be..bf19ddfa6cda 100644
--- a/drivers/ide/pci/scc_pata.c
+++ b/drivers/ide/pci/scc_pata.c
@@ -551,8 +551,8 @@ static int setup_mmio_scc (struct pci_dev *dev, const char *name)
         unsigned long dma_base = pci_resource_start(dev, 1);
         unsigned long ctl_size = pci_resource_len(dev, 0);
         unsigned long dma_size = pci_resource_len(dev, 1);
-        void *ctl_addr;
-        void *dma_addr;
+        void __iomem *ctl_addr;
+        void __iomem *dma_addr;
         int i;
 
         for (i = 0; i < MAX_HWIFS; i++) {
diff --git a/drivers/ieee1394/raw1394.c b/drivers/ieee1394/raw1394.c
index 336e5ff4cfcf..cadf0479cce5 100644
--- a/drivers/ieee1394/raw1394.c
+++ b/drivers/ieee1394/raw1394.c
@@ -2677,7 +2677,7 @@ static long raw1394_iso_xmit_recv_packets32(struct file *file, unsigned int cmd,
                                           struct raw1394_iso_packets32 __user *arg)
 {
         compat_uptr_t infos32;
-        void *infos;
+        void __user *infos;
         long err = -EFAULT;
         struct raw1394_iso_packets __user *dst = compat_alloc_user_space(sizeof(struct raw1394_iso_packets));
 
diff --git a/drivers/lguest/Makefile b/drivers/lguest/Makefile
index 55382c7d799c..e5047471c334 100644
--- a/drivers/lguest/Makefile
+++ b/drivers/lguest/Makefile
@@ -5,3 +5,15 @@ obj-$(CONFIG_LGUEST_GUEST) += lguest.o lguest_asm.o lguest_bus.o
 obj-$(CONFIG_LGUEST)    += lg.o
 lg-y := core.o hypercalls.o page_tables.o interrupts_and_traps.o \
         segments.o io.o lguest_user.o switcher.o
+
+Preparation Preparation!: PREFIX=P
+Guest: PREFIX=G
+Drivers: PREFIX=D
+Launcher: PREFIX=L
+Host: PREFIX=H
+Switcher: PREFIX=S
+Mastery: PREFIX=M
+Beer:
+        @for f in Preparation Guest Drivers Launcher Host Switcher Mastery; do echo "{==- $$f -==}"; make -s $$f; done; echo "{==-==}"
+Preparation Preparation! Guest Drivers Launcher Host Switcher Mastery:
+        @sh ../../Documentation/lguest/extract $(PREFIX) `find ../../* -name '*.[chS]' -wholename '*lguest*'`
diff --git a/drivers/lguest/README b/drivers/lguest/README
new file mode 100644
index 000000000000..b7db39a64c66
--- /dev/null
+++ b/drivers/lguest/README
@@ -0,0 +1,47 @@
+Welcome, friend reader, to lguest.
+
+Lguest is an adventure, with you, the reader, as Hero.  I can't think of many
+5000-line projects which offer both such capability and glimpses of future
+potential; it is an exciting time to be delving into the source!
+
+But be warned; this is an arduous journey of several hours or more!  And as we
+know, all true Heroes are driven by a Noble Goal.  Thus I offer a Beer (or
+equivalent) to anyone I meet who has completed this documentation.
+
+So get comfortable and keep your wits about you (both quick and humorous).
+Along your way to the Noble Goal, you will also gain masterly insight into
+lguest, and hypervisors and x86 virtualization in general.
+
+Our Quest is in seven parts: (best read with C highlighting turned on)
+
+I) Preparation
+        - In which our potential hero is flown quickly over the landscape for a
+          taste of its scope.  Suitable for the armchair coders and other such
+          persons of faint constitution.
+
+II) Guest
+        - Where we encounter the first tantalising wisps of code, and come to
+          understand the details of the life of a Guest kernel.
+
+III) Drivers
+        - Whereby the Guest finds its voice and become useful, and our
+          understanding of the Guest is completed.
+
+IV) Launcher
+        - Where we trace back to the creation of the Guest, and thus begin our
+          understanding of the Host.
+
+V) Host
+        - Where we master the Host code, through a long and tortuous journey.
+          Indeed, it is here that our hero is tested in the Bit of Despair.
+
+VI) Switcher
+        - Where our understanding of the intertwined nature of Guests and Hosts
+          is completed.
+
+VII) Mastery
+        - Where our fully fledged hero grapples with the Great Question:
+          "What next?"
+
+make Preparation!
+Rusty Russell.
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index ce909ec57499..0a46e8837d9a 100644
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -1,5 +1,8 @@
-/* World's simplest hypervisor, to test paravirt_ops and show
- * unbelievers that virtualization is the future.  Plus, it's fun! */
+/*P:400 This contains run_guest() which actually calls into the Host<->Guest
+ * Switcher and analyzes the return, such as determining if the Guest wants the
+ * Host to do something.  This file also contains useful helper routines, and a
+ * couple of non-obvious setup and teardown pieces which were implemented after
+ * days of debugging pain. :*/
 #include <linux/module.h>
 #include <linux/stringify.h>
 #include <linux/stddef.h>
@@ -61,11 +64,33 @@ static struct lguest_pages *lguest_pages(unsigned int cpu)
                   (SWITCHER_ADDR + SHARED_SWITCHER_PAGES*PAGE_SIZE))[cpu]);
 }
 
+/*H:010 We need to set up the Switcher at a high virtual address.  Remember the
+ * Switcher is a few hundred bytes of assembler code which actually changes the
+ * CPU to run the Guest, and then changes back to the Host when a trap or
+ * interrupt happens.
+ *
+ * The Switcher code must be at the same virtual address in the Guest as the
+ * Host since it will be running as the switchover occurs.
+ *
+ * Trying to map memory at a particular address is an unusual thing to do, so
+ * it's not a simple one-liner.  We also set up the per-cpu parts of the
+ * Switcher here.
+ */
 static __init int map_switcher(void)
 {
         int i, err;
         struct page **pagep;
 
+        /*
+         * Map the Switcher in to high memory.
+         *
+         * It turns out that if we choose the address 0xFFC00000 (4MB under the
+         * top virtual address), it makes setting up the page tables really
+         * easy.
+         */
+
+        /* We allocate an array of "struct page"s.  map_vm_area() wants the
+         * pages in this form, rather than just an array of pointers. */
         switcher_page = kmalloc(sizeof(switcher_page[0])*TOTAL_SWITCHER_PAGES,
                                 GFP_KERNEL);
         if (!switcher_page) {
@@ -73,6 +98,8 @@ static __init int map_switcher(void)
                 goto out;
         }
 
+        /* Now we actually allocate the pages.  The Guest will see these pages,
+         * so we make sure they're zeroed. */
         for (i = 0; i < TOTAL_SWITCHER_PAGES; i++) {
                 unsigned long addr = get_zeroed_page(GFP_KERNEL);
                 if (!addr) {
@@ -82,6 +109,9 @@ static __init int map_switcher(void)
                 switcher_page[i] = virt_to_page(addr);
         }
 
+        /* Now we reserve the "virtual memory area" we want: 0xFFC00000
+         * (SWITCHER_ADDR).  We might not get it in theory, but in practice
+         * it's worked so far. */
         switcher_vma = __get_vm_area(TOTAL_SWITCHER_PAGES * PAGE_SIZE,
                                        VM_ALLOC, SWITCHER_ADDR, VMALLOC_END);
         if (!switcher_vma) {
@@ -90,49 +120,105 @@ static __init int map_switcher(void)
                 goto free_pages;
         }
 
+        /* This code actually sets up the pages we've allocated to appear at
+         * SWITCHER_ADDR.  map_vm_area() takes the vma we allocated above, the
+         * kind of pages we're mapping (kernel pages), and a pointer to our
+         * array of struct pages.  It increments that pointer, but we don't
+         * care. */
         pagep = switcher_page;
         err = map_vm_area(switcher_vma, PAGE_KERNEL, &pagep);
         if (err) {
                 printk("lguest: map_vm_area failed: %i\n", err);
                 goto free_vma;
         }
+
+        /* Now the switcher is mapped at the right address, we can't fail!
+         * Copy in the compiled-in Switcher code (from switcher.S). */
         memcpy(switcher_vma->addr, start_switcher_text,
                end_switcher_text - start_switcher_text);
 
-        /* Fix up IDT entries to point into copied text. */
+        /* Most of the switcher.S doesn't care that it's been moved; on Intel,
+         * jumps are relative, and it doesn't access any references to external
+         * code or data.
+         *
+         * The only exception is the interrupt handlers in switcher.S: their
+         * addresses are placed in a table (default_idt_entries), so we need to
+         * update the table with the new addresses.  switcher_offset() is a
+         * convenience function which returns the distance between the builtin
+         * switcher code and the high-mapped copy we just made. */
         for (i = 0; i < IDT_ENTRIES; i++)
                 default_idt_entries[i] += switcher_offset();
 
+        /*
+         * Set up the Switcher's per-cpu areas.
+         *
+         * Each CPU gets two pages of its own within the high-mapped region
+         * (aka. "struct lguest_pages").  Much of this can be initialized now,
+         * but some depends on what Guest we are running (which is set up in
+         * copy_in_guest_info()).
+         */
         for_each_possible_cpu(i) {
+                /* lguest_pages() returns this CPU's two pages. */
                 struct lguest_pages *pages = lguest_pages(i);
+                /* This is a convenience pointer to make the code fit one
+                 * statement to a line. */
                 struct lguest_ro_state *state = &pages->state;
 
-                /* These fields are static: rest done in copy_in_guest_info */
+                /* The Global Descriptor Table: the Host has a different one
+                 * for each CPU.  We keep a descriptor for the GDT which says
+                 * where it is and how big it is (the size is actually the last
+                 * byte, not the size, hence the "-1"). */
                 state->host_gdt_desc.size = GDT_SIZE-1;
                 state->host_gdt_desc.address = (long)get_cpu_gdt_table(i);
+
+                /* All CPUs on the Host use the same Interrupt Descriptor
+                 * Table, so we just use store_idt(), which gets this CPU's IDT
+                 * descriptor. */
                 store_idt(&state->host_idt_desc);
+
+                /* The descriptors for the Guest's GDT and IDT can be filled
+                 * out now, too.  We copy the GDT & IDT into ->guest_gdt and
+                 * ->guest_idt before actually running the Guest. */
                 state->guest_idt_desc.size = sizeof(state->guest_idt)-1;
                 state->guest_idt_desc.address = (long)&state->guest_idt;
                 state->guest_gdt_desc.size = sizeof(state->guest_gdt)-1;
                 state->guest_gdt_desc.address = (long)&state->guest_gdt;
+
+                /* We know where we want the stack to be when the Guest enters
+                 * the switcher: in pages->regs.  The stack grows upwards, so
+                 * we start it at the end of that structure. */
                 state->guest_tss.esp0 = (long)(&pages->regs + 1);
+                /* And this is the GDT entry to use for the stack: we keep a
+                 * couple of special LGUEST entries. */
                 state->guest_tss.ss0 = LGUEST_DS;
-                /* No I/O for you! */
+
+                /* x86 can have a finegrained bitmap which indicates what I/O
+                 * ports the process can use.  We set it to the end of our
+                 * structure, meaning "none". */
                 state->guest_tss.io_bitmap_base = sizeof(state->guest_tss);
+
+                /* Some GDT entries are the same across all Guests, so we can
+                 * set them up now. */
                 setup_default_gdt_entries(state);
+                /* Most IDT entries are the same for all Guests, too.*/
                 setup_default_idt_entries(state, default_idt_entries);
 
-                /* Setup LGUEST segments on all cpus */
+                /* The Host needs to be able to use the LGUEST segments on this
+                 * CPU, too, so put them in the Host GDT. */
                 get_cpu_gdt_table(i)[GDT_ENTRY_LGUEST_CS] = FULL_EXEC_SEGMENT;
                 get_cpu_gdt_table(i)[GDT_ENTRY_LGUEST_DS] = FULL_SEGMENT;
         }
 
-        /* Initialize entry point into switcher. */
+        /* In the Switcher, we want the %cs segment register to use the
+         * LGUEST_CS GDT entry: we've put that in the Host and Guest GDTs, so
+         * it will be undisturbed when we switch.  To change %cs and jump we
+         * need this structure to feed to Intel's "lcall" instruction. */
         lguest_entry.offset = (long)switch_to_guest + switcher_offset();
         lguest_entry.segment = LGUEST_CS;
 
         printk(KERN_INFO "lguest: mapped switcher at %p\n",
                switcher_vma->addr);
+        /* And we succeeded... */
         return 0;
 
 free_vma:
@@ -146,35 +232,58 @@ free_some_pages:
 out:
         return err;
 }
+/*:*/
 
+/* Cleaning up the mapping when the module is unloaded is almost...
+ * too easy. */
 static void unmap_switcher(void)
 {
         unsigned int i;
 
+        /* vunmap() undoes *both* map_vm_area() and __get_vm_area(). */
         vunmap(switcher_vma->addr);
+        /* Now we just need to free the pages we copied the switcher into */
         for (i = 0; i < TOTAL_SWITCHER_PAGES; i++)
                 __free_pages(switcher_page[i], 0);
 }
 
-/* IN/OUT insns: enough to get us past boot-time probing. */
+/*H:130 Our Guest is usually so well behaved; it never tries to do things it
+ * isn't allowed to.  Unfortunately, "struct paravirt_ops" isn't quite
+ * complete, because it doesn't contain replacements for the Intel I/O
+ * instructions.  As a result, the Guest sometimes fumbles across one during
+ * the boot process as it probes for various things which are usually attached
+ * to a PC.
+ *
+ * When the Guest uses one of these instructions, we get trap #13 (General
+ * Protection Fault) and come here.  We see if it's one of those troublesome
+ * instructions and skip over it.  We return true if we did. */
 static int emulate_insn(struct lguest *lg)
 {
         u8 insn;
         unsigned int insnlen = 0, in = 0, shift = 0;
+        /* The eip contains the *virtual* address of the Guest's instruction:
+         * guest_pa just subtracts the Guest's page_offset. */
         unsigned long physaddr = guest_pa(lg, lg->regs->eip);
 
-        /* This only works for addresses in linear mapping... */
+        /* The guest_pa() function only works for Guest kernel addresses, but
+         * that's all we're trying to do anyway. */
         if (lg->regs->eip < lg->page_offset)
                 return 0;
+
+        /* Decoding x86 instructions is icky. */
         lgread(lg, &insn, physaddr, 1);
 
-        /* Operand size prefix means it's actually for ax. */
+        /* 0x66 is an "operand prefix".  It means it's using the upper 16 bits
+           of the eax register. */
         if (insn == 0x66) {
                 shift = 16;
+                /* The instruction is 1 byte so far, read the next byte. */
                 insnlen = 1;
                 lgread(lg, &insn, physaddr + insnlen, 1);
         }
 
+        /* We can ignore the lower bit for the moment and decode the 4 opcodes
+         * we need to emulate. */
         switch (insn & 0xFE) {
         case 0xE4: /* in     <next byte>,%al */
                 insnlen += 2;
@@ -191,9 +300,13 @@ static int emulate_insn(struct lguest *lg)
                 insnlen += 1;
                 break;
         default:
+                /* OK, we don't know what this is, can't emulate. */
                 return 0;
         }
 
+        /* If it was an "IN" instruction, they expect the result to be read
+         * into %eax, so we change %eax.  We always return all-ones, which
+         * traditionally means "there's nothing there". */
         if (in) {
                 /* Lower bit tells is whether it's a 16 or 32 bit access */
                 if (insn & 0x1)
@@ -201,28 +314,46 @@ static int emulate_insn(struct lguest *lg)
                 else
                         lg->regs->eax |= (0xFFFF << shift);
         }
+        /* Finally, we've "done" the instruction, so move past it. */
         lg->regs->eip += insnlen;
+        /* Success! */
         return 1;
 }
-
+/*:*/
+
+/*L:305
+ * Dealing With Guest Memory.
+ *
+ * When the Guest gives us (what it thinks is) a physical address, we can use
+ * the normal copy_from_user() & copy_to_user() on that address: remember,
+ * Guest physical == Launcher virtual.
+ *
+ * But we can't trust the Guest: it might be trying to access the Launcher
+ * code.  We have to check that the range is below the pfn_limit the Launcher
+ * gave us.  We have to make sure that addr + len doesn't give us a false
+ * positive by overflowing, too. */
 int lguest_address_ok(const struct lguest *lg,
                       unsigned long addr, unsigned long len)
 {
         return (addr+len) / PAGE_SIZE < lg->pfn_limit && (addr+len >= addr);
 }
 
-/* Just like get_user, but don't let guest access lguest binary. */
+/* This is a convenient routine to get a 32-bit value from the Guest (a very
+ * common operation).  Here we can see how useful the kill_lguest() routine we
+ * met in the Launcher can be: we return a random value (0) instead of needing
+ * to return an error. */
 u32 lgread_u32(struct lguest *lg, unsigned long addr)
 {
         u32 val = 0;
 
-        /* Don't let them access lguest binary */
+        /* Don't let them access lguest binary. */
         if (!lguest_address_ok(lg, addr, sizeof(val))
             || get_user(val, (u32 __user *)addr) != 0)
                 kill_guest(lg, "bad read address %#lx", addr);
         return val;
 }
 
+/* Same thing for writing a value. */
 void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val)
 {
         if (!lguest_address_ok(lg, addr, sizeof(val))
@@ -230,6 +361,9 @@ void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val)
                 kill_guest(lg, "bad write address %#lx", addr);
 }
 
+/* This routine is more generic, and copies a range of Guest bytes into a
+ * buffer.  If the copy_from_user() fails, we fill the buffer with zeroes, so
+ * the caller doesn't end up using uninitialized kernel memory. */
 void lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes)
 {
         if (!lguest_address_ok(lg, addr, bytes)
@@ -240,6 +374,7 @@ void lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes)
         }
 }
 
+/* Similarly, our generic routine to copy into a range of Guest bytes. */
 void lgwrite(struct lguest *lg, unsigned long addr, const void *b,
              unsigned bytes)
 {
@@ -247,6 +382,7 @@ void lgwrite(struct lguest *lg, unsigned long addr, const void *b,
             || copy_to_user((void __user *)addr, b, bytes) != 0)
                 kill_guest(lg, "bad write address %#lx len %u", addr, bytes);
 }
+/* (end of memory access helper routines) :*/
 
 static void set_ts(void)
 {
@@ -257,54 +393,108 @@ static void set_ts(void)
                 write_cr0(cr0|8);
 }
 
+/*S:010
+ * We are getting close to the Switcher.
+ *
+ * Remember that each CPU has two pages which are visible to the Guest when it
+ * runs on that CPU.  This has to contain the state for that Guest: we copy the
+ * state in just before we run the Guest.
+ *
+ * Each Guest has "changed" flags which indicate what has changed in the Guest
+ * since it last ran.  We saw this set in interrupts_and_traps.c and
+ * segments.c.
+ */
 static void copy_in_guest_info(struct lguest *lg, struct lguest_pages *pages)
 {
+        /* Copying all this data can be quite expensive.  We usually run the
+         * same Guest we ran last time (and that Guest hasn't run anywhere else
+         * meanwhile).  If that's not the case, we pretend everything in the
+         * Guest has changed. */
         if (__get_cpu_var(last_guest) != lg || lg->last_pages != pages) {
                 __get_cpu_var(last_guest) = lg;
                 lg->last_pages = pages;
                 lg->changed = CHANGED_ALL;
         }
 
-        /* These are pretty cheap, so we do them unconditionally. */
+        /* These copies are pretty cheap, so we do them unconditionally: */
+        /* Save the current Host top-level page directory. */
         pages->state.host_cr3 = __pa(current->mm->pgd);
+        /* Set up the Guest's page tables to see this CPU's pages (and no
+         * other CPU's pages). */
         map_switcher_in_guest(lg, pages);
+        /* Set up the two "TSS" members which tell the CPU what stack to use
+         * for traps which do directly into the Guest (ie. traps at privilege
+         * level 1). */
         pages->state.guest_tss.esp1 = lg->esp1;
         pages->state.guest_tss.ss1 = lg->ss1;
 
-        /* Copy direct trap entries. */
+        /* Copy direct-to-Guest trap entries. */
         if (lg->changed & CHANGED_IDT)
                 copy_traps(lg, pages->state.guest_idt, default_idt_entries);
 
-        /* Copy all GDT entries but the TSS. */
+        /* Copy all GDT entries which the Guest can change. */
         if (lg->changed & CHANGED_GDT)
                 copy_gdt(lg, pages->state.guest_gdt);
         /* If only the TLS entries have changed, copy them. */
         else if (lg->changed & CHANGED_GDT_TLS)
                 copy_gdt_tls(lg, pages->state.guest_gdt);
 
+        /* Mark the Guest as unchanged for next time. */
         lg->changed = 0;
 }
 
+/* Finally: the code to actually call into the Switcher to run the Guest. */
 static void run_guest_once(struct lguest *lg, struct lguest_pages *pages)
 {
+        /* This is a dummy value we need for GCC's sake. */
         unsigned int clobber;
 
+        /* Copy the guest-specific information into this CPU's "struct
+         * lguest_pages". */
         copy_in_guest_info(lg, pages);
 
-        /* Put eflags on stack, lcall does rest: suitable for iret return. */
+        /* Now: we push the "eflags" register on the stack, then do an "lcall".
+         * This is how we change from using the kernel code segment to using
+         * the dedicated lguest code segment, as well as jumping into the
+         * Switcher.
+         *
+         * The lcall also pushes the old code segment (KERNEL_CS) onto the
+         * stack, then the address of this call.  This stack layout happens to
+         * exactly match the stack of an interrupt... */
         asm volatile("pushf; lcall *lguest_entry"
+                     /* This is how we tell GCC that %eax ("a") and %ebx ("b")
+                      * are changed by this routine.  The "=" means output. */
                      : "=a"(clobber), "=b"(clobber)
+                     /* %eax contains the pages pointer.  ("0" refers to the
+                      * 0-th argument above, ie "a").  %ebx contains the
+                      * physical address of the Guest's top-level page
+                      * directory. */
                      : "0"(pages), "1"(__pa(lg->pgdirs[lg->pgdidx].pgdir))
+                     /* We tell gcc that all these registers could change,
+                      * which means we don't have to save and restore them in
+                      * the Switcher. */
                      : "memory", "%edx", "%ecx", "%edi", "%esi");
 }
+/*:*/
 
+/*H:030 Let's jump straight to the the main loop which runs the Guest.
+ * Remember, this is called by the Launcher reading /dev/lguest, and we keep
+ * going around and around until something interesting happens. */
 int run_guest(struct lguest *lg, unsigned long __user *user)
 {
+        /* We stop running once the Guest is dead. */
         while (!lg->dead) {
+                /* We need to initialize this, otherwise gcc complains.  It's
+                 * not (yet) clever enough to see that it's initialized when we
+                 * need it. */
                 unsigned int cr2 = 0; /* Damn gcc */
 
-                /* Hypercalls first: we might have been out to userspace */
+                /* First we run any hypercalls the Guest wants done: either in
+                 * the hypercall ring in "struct lguest_data", or directly by
+                 * using int 31 (LGUEST_TRAP_ENTRY). */
                 do_hypercalls(lg);
+                /* It's possible the Guest did a SEND_DMA hypercall to the
+                 * Launcher, in which case we return from the read() now. */
                 if (lg->dma_is_pending) {
                         if (put_user(lg->pending_dma, user) ||
                             put_user(lg->pending_key, user+1))
@@ -312,6 +502,7 @@ int run_guest(struct lguest *lg, unsigned long __user *user)
                         return sizeof(unsigned long)*2;
                 }
 
+                /* Check for signals */
                 if (signal_pending(current))
                         return -ERESTARTSYS;
 
@@ -319,77 +510,154 @@ int run_guest(struct lguest *lg, unsigned long __user *user)
                 if (lg->break_out)
                         return -EAGAIN;
 
+                /* Check if there are any interrupts which can be delivered
+                 * now: if so, this sets up the hander to be executed when we
+                 * next run the Guest. */
                 maybe_do_interrupt(lg);
 
+                /* All long-lived kernel loops need to check with this horrible
+                 * thing called the freezer.  If the Host is trying to suspend,
+                 * it stops us. */
                 try_to_freeze();
 
+                /* Just make absolutely sure the Guest is still alive.  One of
+                 * those hypercalls could have been fatal, for example. */
                 if (lg->dead)
                         break;
 
+                /* If the Guest asked to be stopped, we sleep.  The Guest's
+                 * clock timer or LHCALL_BREAK from the Waker will wake us. */
                 if (lg->halted) {
                         set_current_state(TASK_INTERRUPTIBLE);
                         schedule();
                         continue;
                 }
 
+                /* OK, now we're ready to jump into the Guest.  First we put up
+                 * the "Do Not Disturb" sign: */
                 local_irq_disable();
 
-                /* Even if *we* don't want FPU trap, guest might... */
+                /* Remember the awfully-named TS bit?  If the Guest has asked
+                 * to set it we set it now, so we can trap and pass that trap
+                 * to the Guest if it uses the FPU. */
                 if (lg->ts)
                         set_ts();
 
-                /* Don't let Guest do SYSENTER: we can't handle it. */
+                /* SYSENTER is an optimized way of doing system calls.  We
+                 * can't allow it because it always jumps to privilege level 0.
+                 * A normal Guest won't try it because we don't advertise it in
+                 * CPUID, but a malicious Guest (or malicious Guest userspace
+                 * program) could, so we tell the CPU to disable it before
+                 * running the Guest. */
                 if (boot_cpu_has(X86_FEATURE_SEP))
                         wrmsr(MSR_IA32_SYSENTER_CS, 0, 0);
 
+                /* Now we actually run the Guest.  It will pop back out when
+                 * something interesting happens, and we can examine its
+                 * registers to see what it was doing. */
                 run_guest_once(lg, lguest_pages(raw_smp_processor_id()));
 
-                /* Save cr2 now if we page-faulted. */
+                /* The "regs" pointer contains two extra entries which are not
+                 * really registers: a trap number which says what interrupt or
+                 * trap made the switcher code come back, and an error code
+                 * which some traps set.  */
+
+                /* If the Guest page faulted, then the cr2 register will tell
+                 * us the bad virtual address.  We have to grab this now,
+                 * because once we re-enable interrupts an interrupt could
+                 * fault and thus overwrite cr2, or we could even move off to a
+                 * different CPU. */
                 if (lg->regs->trapnum == 14)
                         cr2 = read_cr2();
+                /* Similarly, if we took a trap because the Guest used the FPU,
+                 * we have to restore the FPU it expects to see. */
                 else if (lg->regs->trapnum == 7)
                         math_state_restore();
 
+                /* Restore SYSENTER if it's supposed to be on. */
                 if (boot_cpu_has(X86_FEATURE_SEP))
                         wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+
+                /* Now we're ready to be interrupted or moved to other CPUs */
                 local_irq_enable();
 
+                /* OK, so what happened? */
                 switch (lg->regs->trapnum) {
                 case 13: /* We've intercepted a GPF. */
+                        /* Check if this was one of those annoying IN or OUT
+                         * instructions which we need to emulate.  If so, we
+                         * just go back into the Guest after we've done it. */
                         if (lg->regs->errcode == 0) {
                                 if (emulate_insn(lg))
                                         continue;
                         }
                         break;
                 case 14: /* We've intercepted a page fault. */
+                        /* The Guest accessed a virtual address that wasn't
+                         * mapped.  This happens a lot: we don't actually set
+                         * up most of the page tables for the Guest at all when
+                         * we start: as it runs it asks for more and more, and
+                         * we set them up as required. In this case, we don't
+                         * even tell the Guest that the fault happened.
+                         *
+                         * The errcode tells whether this was a read or a
+                         * write, and whether kernel or userspace code. */
                         if (demand_page(lg, cr2, lg->regs->errcode))
                                 continue;
 
-                        /* If lguest_data is NULL, this won't hurt. */
+                        /* OK, it's really not there (or not OK): the Guest
+                         * needs to know.  We write out the cr2 value so it
+                         * knows where the fault occurred.
+                         *
+                         * Note that if the Guest were really messed up, this
+                         * could happen before it's done the INITIALIZE
+                         * hypercall, so lg->lguest_data will be NULL, so
+                         * &lg->lguest_data->cr2 will be address 8.  Writing
+                         * into that address won't hurt the Host at all,
+                         * though. */
                         if (put_user(cr2, &lg->lguest_data->cr2))
                                 kill_guest(lg, "Writing cr2");
                         break;
                 case 7: /* We've intercepted a Device Not Available fault. */
-                        /* If they don't want to know, just absorb it. */
+                        /* If the Guest doesn't want to know, we already
+                         * restored the Floating Point Unit, so we just
+                         * continue without telling it. */
                         if (!lg->ts)
                                 continue;
                         break;
-                case 32 ... 255: /* Real interrupt, fall thru */
+                case 32 ... 255:
+                        /* These values mean a real interrupt occurred, in
+                         * which case the Host handler has already been run.
+                         * We just do a friendly check if another process
+                         * should now be run, then fall through to loop
+                         * around: */
                         cond_resched();
                 case LGUEST_TRAP_ENTRY: /* Handled at top of loop */
                         continue;
                 }
 
+                /* If we get here, it's a trap the Guest wants to know
+                 * about. */
                 if (deliver_trap(lg, lg->regs->trapnum))
                         continue;
 
+                /* If the Guest doesn't have a handler (either it hasn't
+                 * registered any yet, or it's one of the faults we don't let
+                 * it handle), it dies with a cryptic error message. */
                 kill_guest(lg, "unhandled trap %li at %#lx (%#lx)",
                            lg->regs->trapnum, lg->regs->eip,
                            lg->regs->trapnum == 14 ? cr2 : lg->regs->errcode);
         }
+        /* The Guest is dead => "No such file or directory" */
         return -ENOENT;
 }
 
+/* Now we can look at each of the routines this calls, in increasing order of
+ * complexity: do_hypercalls(), emulate_insn(), maybe_do_interrupt(),
+ * deliver_trap() and demand_page().  After all those, we'll be ready to
+ * examine the Switcher, and our philosophical understanding of the Host/Guest
+ * duality will be complete. :*/
+
 int find_free_guest(void)
 {
         unsigned int i;
@@ -407,55 +675,96 @@ static void adjust_pge(void *on)
                 write_cr4(read_cr4() & ~X86_CR4_PGE);
 }
 
+/*H:000
+ * Welcome to the Host!
+ *
+ * By this point your brain has been tickled by the Guest code and numbed by
+ * the Launcher code; prepare for it to be stretched by the Host code.  This is
+ * the heart.  Let's begin at the initialization routine for the Host's lg
+ * module.
+ */
 static int __init init(void)
 {
         int err;
 
+        /* Lguest can't run under Xen, VMI or itself.  It does Tricky Stuff. */
         if (paravirt_enabled()) {
                 printk("lguest is afraid of %s\n", paravirt_ops.name);
                 return -EPERM;
         }
 
+        /* First we put the Switcher up in very high virtual memory. */
         err = map_switcher();
         if (err)
                 return err;
 
+        /* Now we set up the pagetable implementation for the Guests. */
         err = init_pagetables(switcher_page, SHARED_SWITCHER_PAGES);
         if (err) {
                 unmap_switcher();
                 return err;
         }
+
+        /* The I/O subsystem needs some things initialized. */
         lguest_io_init();
 
+        /* /dev/lguest needs to be registered. */
         err = lguest_device_init();
         if (err) {
                 free_pagetables();
                 unmap_switcher();
                 return err;
         }
+
+        /* Finally, we need to turn off "Page Global Enable".  PGE is an
+         * optimization where page table entries are specially marked to show
+         * they never change.  The Host kernel marks all the kernel pages this
+         * way because it's always present, even when userspace is running.
+         *
+         * Lguest breaks this: unbeknownst to the rest of the Host kernel, we
+         * switch to the Guest kernel.  If you don't disable this on all CPUs,
+         * you'll get really weird bugs that you'll chase for two days.
+         *
+         * I used to turn PGE off every time we switched to the Guest and back
+         * on when we return, but that slowed the Switcher down noticibly. */
+
+        /* We don't need the complexity of CPUs coming and going while we're
+         * doing this. */
         lock_cpu_hotplug();
         if (cpu_has_pge) { /* We have a broader idea of "global". */
+                /* Remember that this was originally set (for cleanup). */
                 cpu_had_pge = 1;
+                /* adjust_pge is a helper function which sets or unsets the PGE
+                 * bit on its CPU, depending on the argument (0 == unset). */
                 on_each_cpu(adjust_pge, (void *)0, 0, 1);
+                /* Turn off the feature in the global feature set. */
                 clear_bit(X86_FEATURE_PGE, boot_cpu_data.x86_capability);
         }
         unlock_cpu_hotplug();
+
+        /* All good! */
         return 0;
 }
 
+/* Cleaning up is just the same code, backwards.  With a little French. */
 static void __exit fini(void)
 {
         lguest_device_remove();
         free_pagetables();
         unmap_switcher();
+
+        /* If we had PGE before we started, turn it back on now. */
         lock_cpu_hotplug();
         if (cpu_had_pge) {
                 set_bit(X86_FEATURE_PGE, boot_cpu_data.x86_capability);
+                /* adjust_pge's argument "1" means set PGE. */
                 on_each_cpu(adjust_pge, (void *)1, 0, 1);
         }
         unlock_cpu_hotplug();
 }
 
+/* The Host side of lguest can be a module.  This is a nice way for people to
+ * play with it.  */
 module_init(init);
 module_exit(fini);
 MODULE_LICENSE("GPL");
diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c
index ea52ca451f74..7a5299f9679d 100644
--- a/drivers/lguest/hypercalls.c
+++ b/drivers/lguest/hypercalls.c
@@ -1,5 +1,10 @@
-/*  Actual hypercalls, which allow guests to actually do something.
-    Copyright (C) 2006 Rusty Russell IBM Corporation
+/*P:500 Just as userspace programs request kernel operations through a system
+ * call, the Guest requests Host operations through a "hypercall".  You might
+ * notice this nomenclature doesn't really follow any logic, but the name has
+ * been around for long enough that we're stuck with it.  As you'd expect, this
+ * code is basically a one big switch statement. :*/
+
+/*  Copyright (C) 2006 Rusty Russell IBM Corporation
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -23,37 +28,63 @@
 #include <irq_vectors.h>
 #include "lg.h"
 
+/*H:120 This is the core hypercall routine: where the Guest gets what it
+ * wants.  Or gets killed.  Or, in the case of LHCALL_CRASH, both.
+ *
+ * Remember from the Guest: %eax == which call to make, and the arguments are
+ * packed into %edx, %ebx and %ecx if needed. */
 static void do_hcall(struct lguest *lg, struct lguest_regs *regs)
 {
         switch (regs->eax) {
         case LHCALL_FLUSH_ASYNC:
+                /* This call does nothing, except by breaking out of the Guest
+                 * it makes us process all the asynchronous hypercalls. */
                 break;
         case LHCALL_LGUEST_INIT:
+                /* You can't get here unless you're already initialized.  Don't
+                 * do that. */
                 kill_guest(lg, "already have lguest_data");
                 break;
         case LHCALL_CRASH: {
+                /* Crash is such a trivial hypercall that we do it in four
+                 * lines right here. */
                 char msg[128];
+                /* If the lgread fails, it will call kill_guest() itself; the
+                 * kill_guest() with the message will be ignored. */
                 lgread(lg, msg, regs->edx, sizeof(msg));
                 msg[sizeof(msg)-1] = '\0';
                 kill_guest(lg, "CRASH: %s", msg);
                 break;
         }
         case LHCALL_FLUSH_TLB:
+                /* FLUSH_TLB comes in two flavors, depending on the
+                 * argument: */
                 if (regs->edx)
                         guest_pagetable_clear_all(lg);
                 else
                         guest_pagetable_flush_user(lg);
                 break;
         case LHCALL_GET_WALLCLOCK: {
+                /* The Guest wants to know the real time in seconds since 1970,
+                 * in good Unix tradition. */
                 struct timespec ts;
                 ktime_get_real_ts(&ts);
                 regs->eax = ts.tv_sec;
                 break;
         }
         case LHCALL_BIND_DMA:
+                /* BIND_DMA really wants four arguments, but it's the only call
+                 * which does.  So the Guest packs the number of buffers and
+                 * the interrupt number into the final argument, and we decode
+                 * it here.  This can legitimately fail, since we currently
+                 * place a limit on the number of DMA pools a Guest can have.
+                 * So we return true or false from this call. */
                 regs->eax = bind_dma(lg, regs->edx, regs->ebx,
                                      regs->ecx >> 8, regs->ecx & 0xFF);
                 break;
+
+        /* All these calls simply pass the arguments through to the right
+         * routines. */
         case LHCALL_SEND_DMA:
                 send_dma(lg, regs->edx, regs->ebx);
                 break;
@@ -81,10 +112,13 @@ static void do_hcall(struct lguest *lg, struct lguest_regs *regs)
         case LHCALL_SET_CLOCKEVENT:
                 guest_set_clockevent(lg, regs->edx);
                 break;
+
         case LHCALL_TS:
+                /* This sets the TS flag, as we saw used in run_guest(). */
                 lg->ts = regs->edx;
                 break;
         case LHCALL_HALT:
+                /* Similarly, this sets the halted flag for run_guest(). */
                 lg->halted = 1;
                 break;
         default:
@@ -92,25 +126,42 @@ static void do_hcall(struct lguest *lg, struct lguest_regs *regs)
         }
 }
 
-/* We always do queued calls before actual hypercall. */
+/* Asynchronous hypercalls are easy: we just look in the array in the Guest's
+ * "struct lguest_data" and see if there are any new ones marked "ready".
+ *
+ * We are careful to do these in order: obviously we respect the order the
+ * Guest put them in the ring, but we also promise the Guest that they will
+ * happen before any normal hypercall (which is why we check this before
+ * checking for a normal hcall). */
 static void do_async_hcalls(struct lguest *lg)
 {
         unsigned int i;
         u8 st[LHCALL_RING_SIZE];
 
+        /* For simplicity, we copy the entire call status array in at once. */
         if (copy_from_user(&st, &lg->lguest_data->hcall_status, sizeof(st)))
                 return;
 
+
+        /* We process "struct lguest_data"s hcalls[] ring once. */
         for (i = 0; i < ARRAY_SIZE(st); i++) {
                 struct lguest_regs regs;
+                /* We remember where we were up to from last time.  This makes
+                 * sure that the hypercalls are done in the order the Guest
+                 * places them in the ring. */
                 unsigned int n = lg->next_hcall;
 
+                /* 0xFF means there's no call here (yet). */
                 if (st[n] == 0xFF)
                         break;
 
+                /* OK, we have hypercall.  Increment the "next_hcall" cursor,
+                 * and wrap back to 0 if we reach the end. */
                 if (++lg->next_hcall == LHCALL_RING_SIZE)
                         lg->next_hcall = 0;
 
+                /* We copy the hypercall arguments into a fake register
+                 * structure.  This makes life simple for do_hcall(). */
                 if (get_user(regs.eax, &lg->lguest_data->hcalls[n].eax)
                     || get_user(regs.edx, &lg->lguest_data->hcalls[n].edx)
                     || get_user(regs.ecx, &lg->lguest_data->hcalls[n].ecx)
@@ -119,74 +170,126 @@ static void do_async_hcalls(struct lguest *lg)
                         break;
                 }
 
+                /* Do the hypercall, same as a normal one. */
                 do_hcall(lg, &regs);
+
+                /* Mark the hypercall done. */
                 if (put_user(0xFF, &lg->lguest_data->hcall_status[n])) {
                         kill_guest(lg, "Writing result for async hypercall");
                         break;
                 }
 
+                /* Stop doing hypercalls if we've just done a DMA to the
+                 * Launcher: it needs to service this first. */
                 if (lg->dma_is_pending)
                         break;
         }
 }
 
+/* Last of all, we look at what happens first of all.  The very first time the
+ * Guest makes a hypercall, we end up here to set things up: */
 static void initialize(struct lguest *lg)
 {
         u32 tsc_speed;
 
+        /* You can't do anything until you're initialized.  The Guest knows the
+         * rules, so we're unforgiving here. */
         if (lg->regs->eax != LHCALL_LGUEST_INIT) {
                 kill_guest(lg, "hypercall %li before LGUEST_INIT",
                            lg->regs->eax);
                 return;
         }
 
-        /* We only tell the guest to use the TSC if it's reliable. */
+        /* We insist that the Time Stamp Counter exist and doesn't change with
+         * cpu frequency.  Some devious chip manufacturers decided that TSC
+         * changes could be handled in software.  I decided that time going
+         * backwards might be good for benchmarks, but it's bad for users.
+         *
+         * We also insist that the TSC be stable: the kernel detects unreliable
+         * TSCs for its own purposes, and we use that here. */
         if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC) && !check_tsc_unstable())
                 tsc_speed = tsc_khz;
         else
                 tsc_speed = 0;
 
+        /* The pointer to the Guest's "struct lguest_data" is the only
+         * argument. */
         lg->lguest_data = (struct lguest_data __user *)lg->regs->edx;
-        /* We check here so we can simply copy_to_user/from_user */
+        /* If we check the address they gave is OK now, we can simply
+         * copy_to_user/from_user from now on rather than using lgread/lgwrite.
+         * I put this in to show that I'm not immune to writing stupid
+         * optimizations. */
         if (!lguest_address_ok(lg, lg->regs->edx, sizeof(*lg->lguest_data))) {
                 kill_guest(lg, "bad guest page %p", lg->lguest_data);
                 return;
         }
+        /* The Guest tells us where we're not to deliver interrupts by putting
+         * the range of addresses into "struct lguest_data". */
         if (get_user(lg->noirq_start, &lg->lguest_data->noirq_start)
             || get_user(lg->noirq_end, &lg->lguest_data->noirq_end)
-            /* We reserve the top pgd entry. */
+            /* We tell the Guest that it can't use the top 4MB of virtual
+             * addresses used by the Switcher. */
             || put_user(4U*1024*1024, &lg->lguest_data->reserve_mem)
             || put_user(tsc_speed, &lg->lguest_data->tsc_khz)
+            /* We also give the Guest a unique id, as used in lguest_net.c. */
             || put_user(lg->guestid, &lg->lguest_data->guestid))
                 kill_guest(lg, "bad guest page %p", lg->lguest_data);
 
-        /* This is the one case where the above accesses might have
-         * been the first write to a Guest page.  This may have caused
-         * a copy-on-write fault, but the Guest might be referring to
-         * the old (read-only) page. */
+        /* This is the one case where the above accesses might have been the
+         * first write to a Guest page.  This may have caused a copy-on-write
+         * fault, but the Guest might be referring to the old (read-only)
+         * page. */
         guest_pagetable_clear_all(lg);
 }
+/* Now we've examined the hypercall code; our Guest can make requests.  There
+ * is one other way we can do things for the Guest, as we see in
+ * emulate_insn(). */
 
-/* Even if we go out to userspace and come back, we don't want to do
- * the hypercall again. */
+/*H:110 Tricky point: we mark the hypercall as "done" once we've done it.
+ * Normally we don't need to do this: the Guest will run again and update the
+ * trap number before we come back around the run_guest() loop to
+ * do_hypercalls().
+ *
+ * However, if we are signalled or the Guest sends DMA to the Launcher, that
+ * loop will exit without running the Guest.  When it comes back it would try
+ * to re-run the hypercall. */
 static void clear_hcall(struct lguest *lg)
 {
         lg->regs->trapnum = 255;
 }
 
+/*H:100
+ * Hypercalls
+ *
+ * Remember from the Guest, hypercalls come in two flavors: normal and
+ * asynchronous.  This file handles both of types.
+ */
 void do_hypercalls(struct lguest *lg)
 {
+        /* Not initialized yet? */
         if (unlikely(!lg->lguest_data)) {
+                /* Did the Guest make a hypercall?  We might have come back for
+                 * some other reason (an interrupt, a different trap). */
                 if (lg->regs->trapnum == LGUEST_TRAP_ENTRY) {
+                        /* Set up the "struct lguest_data" */
                         initialize(lg);
+                        /* The hypercall is done. */
                         clear_hcall(lg);
                 }
                 return;
         }
 
+        /* The Guest has initialized.
+         *
+         * Look in the hypercall ring for the async hypercalls: */
         do_async_hcalls(lg);
+
+        /* If we stopped reading the hypercall ring because the Guest did a
+         * SEND_DMA to the Launcher, we want to return now.  Otherwise if the
+         * Guest asked us to do a hypercall, we do it. */
         if (!lg->dma_is_pending && lg->regs->trapnum == LGUEST_TRAP_ENTRY) {
                 do_hcall(lg, lg->regs);
+                /* The hypercall is done. */
                 clear_hcall(lg);
         }
 }
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index bee029bb2c7b..bd0091bf79ec 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -1,100 +1,160 @@
+/*P:800 Interrupts (traps) are complicated enough to earn their own file.
+ * There are three classes of interrupts:
+ *
+ * 1) Real hardware interrupts which occur while we're running the Guest,
+ * 2) Interrupts for virtual devices attached to the Guest, and
+ * 3) Traps and faults from the Guest.
+ *
+ * Real hardware interrupts must be delivered to the Host, not the Guest.
+ * Virtual interrupts must be delivered to the Guest, but we make them look
+ * just like real hardware would deliver them.  Traps from the Guest can be set
+ * up to go directly back into the Guest, but sometimes the Host wants to see
+ * them first, so we also have a way of "reflecting" them into the Guest as if
+ * they had been delivered to it directly. :*/
 #include <linux/uaccess.h>
 #include "lg.h"
 
+/* The address of the interrupt handler is split into two bits: */
 static unsigned long idt_address(u32 lo, u32 hi)
 {
         return (lo & 0x0000FFFF) | (hi & 0xFFFF0000);
 }
 
+/* The "type" of the interrupt handler is a 4 bit field: we only support a
+ * couple of types. */
 static int idt_type(u32 lo, u32 hi)
 {
         return (hi >> 8) & 0xF;
 }
 
+/* An IDT entry can't be used unless the "present" bit is set. */
 static int idt_present(u32 lo, u32 hi)
 {
         return (hi & 0x8000);
 }
 
+/* We need a helper to "push" a value onto the Guest's stack, since that's a
+ * big part of what delivering an interrupt does. */
 static void push_guest_stack(struct lguest *lg, unsigned long *gstack, u32 val)
 {
+        /* Stack grows upwards: move stack then write value. */
         *gstack -= 4;
         lgwrite_u32(lg, *gstack, val);
 }
 
+/*H:210 The set_guest_interrupt() routine actually delivers the interrupt or
+ * trap.  The mechanics of delivering traps and interrupts to the Guest are the
+ * same, except some traps have an "error code" which gets pushed onto the
+ * stack as well: the caller tells us if this is one.
+ *
+ * "lo" and "hi" are the two parts of the Interrupt Descriptor Table for this
+ * interrupt or trap.  It's split into two parts for traditional reasons: gcc
+ * on i386 used to be frightened by 64 bit numbers.
+ *
+ * We set up the stack just like the CPU does for a real interrupt, so it's
+ * identical for the Guest (and the standard "iret" instruction will undo
+ * it). */
 static void set_guest_interrupt(struct lguest *lg, u32 lo, u32 hi, int has_err)
 {
         unsigned long gstack;
         u32 eflags, ss, irq_enable;
 
-        /* If they want a ring change, we use new stack and push old ss/esp */
+        /* There are two cases for interrupts: one where the Guest is already
+         * in the kernel, and a more complex one where the Guest is in
+         * userspace.  We check the privilege level to find out. */
         if ((lg->regs->ss&0x3) != GUEST_PL) {
+                /* The Guest told us their kernel stack with the SET_STACK
+                 * hypercall: both the virtual address and the segment */
                 gstack = guest_pa(lg, lg->esp1);
                 ss = lg->ss1;
+                /* We push the old stack segment and pointer onto the new
+                 * stack: when the Guest does an "iret" back from the interrupt
+                 * handler the CPU will notice they're dropping privilege
+                 * levels and expect these here. */
                 push_guest_stack(lg, &gstack, lg->regs->ss);
                 push_guest_stack(lg, &gstack, lg->regs->esp);
         } else {
+                /* We're staying on the same Guest (kernel) stack. */
                 gstack = guest_pa(lg, lg->regs->esp);
                 ss = lg->regs->ss;
         }
 
-        /* We use IF bit in eflags to indicate whether irqs were enabled
-           (it's always 1, since irqs are enabled when guest is running). */
+        /* Remember that we never let the Guest actually disable interrupts, so
+         * the "Interrupt Flag" bit is always set.  We copy that bit from the
+         * Guest's "irq_enabled" field into the eflags word: the Guest copies
+         * it back in "lguest_iret". */
         eflags = lg->regs->eflags;
         if (get_user(irq_enable, &lg->lguest_data->irq_enabled) == 0
             && !(irq_enable & X86_EFLAGS_IF))
                 eflags &= ~X86_EFLAGS_IF;
 
+        /* An interrupt is expected to push three things on the stack: the old
+         * "eflags" word, the old code segment, and the old instruction
+         * pointer. */
         push_guest_stack(lg, &gstack, eflags);
         push_guest_stack(lg, &gstack, lg->regs->cs);
         push_guest_stack(lg, &gstack, lg->regs->eip);
 
+        /* For the six traps which supply an error code, we push that, too. */
         if (has_err)
                 push_guest_stack(lg, &gstack, lg->regs->errcode);
 
-        /* Change the real stack so switcher returns to trap handler */
+        /* Now we've pushed all the old state, we change the stack, the code
+         * segment and the address to execute. */
         lg->regs->ss = ss;
         lg->regs->esp = gstack + lg->page_offset;
         lg->regs->cs = (__KERNEL_CS|GUEST_PL);
         lg->regs->eip = idt_address(lo, hi);
 
-        /* Disable interrupts for an interrupt gate. */
+        /* There are two kinds of interrupt handlers: 0xE is an "interrupt
+         * gate" which expects interrupts to be disabled on entry. */
         if (idt_type(lo, hi) == 0xE)
                 if (put_user(0, &lg->lguest_data->irq_enabled))
                         kill_guest(lg, "Disabling interrupts");
 }
 
+/*H:200
+ * Virtual Interrupts.
+ *
+ * maybe_do_interrupt() gets called before every entry to the Guest, to see if
+ * we should divert the Guest to running an interrupt handler. */
 void maybe_do_interrupt(struct lguest *lg)
 {
         unsigned int irq;
         DECLARE_BITMAP(blk, LGUEST_IRQS);
         struct desc_struct *idt;
 
+        /* If the Guest hasn't even initialized yet, we can do nothing. */
         if (!lg->lguest_data)
                 return;
 
-        /* Mask out any interrupts they have blocked. */
+        /* Take our "irqs_pending" array and remove any interrupts the Guest
+         * wants blocked: the result ends up in "blk". */
         if (copy_from_user(&blk, lg->lguest_data->blocked_interrupts,
                            sizeof(blk)))
                 return;
 
         bitmap_andnot(blk, lg->irqs_pending, blk, LGUEST_IRQS);
 
+        /* Find the first interrupt. */
         irq = find_first_bit(blk, LGUEST_IRQS);
+        /* None?  Nothing to do */
         if (irq >= LGUEST_IRQS)
                 return;
 
+        /* They may be in the middle of an iret, where they asked us never to
+         * deliver interrupts. */
         if (lg->regs->eip >= lg->noirq_start && lg->regs->eip < lg->noirq_end)
                 return;
 
-        /* If they're halted, we re-enable interrupts. */
+        /* If they're halted, interrupts restart them. */
         if (lg->halted) {
                 /* Re-enable interrupts. */
                 if (put_user(X86_EFLAGS_IF, &lg->lguest_data->irq_enabled))
                         kill_guest(lg, "Re-enabling interrupts");
                 lg->halted = 0;
         } else {
-                /* Maybe they have interrupts disabled? */
+                /* Otherwise we check if they have interrupts disabled. */
                 u32 irq_enabled;
                 if (get_user(irq_enabled, &lg->lguest_data->irq_enabled))
                         irq_enabled = 0;
@@ -102,112 +162,211 @@ void maybe_do_interrupt(struct lguest *lg)
                         return;
         }
 
+        /* Look at the IDT entry the Guest gave us for this interrupt.  The
+         * first 32 (FIRST_EXTERNAL_VECTOR) entries are for traps, so we skip
+         * over them. */
         idt = &lg->idt[FIRST_EXTERNAL_VECTOR+irq];
+        /* If they don't have a handler (yet?), we just ignore it */
         if (idt_present(idt->a, idt->b)) {
+                /* OK, mark it no longer pending and deliver it. */
                 clear_bit(irq, lg->irqs_pending);
+                /* set_guest_interrupt() takes the interrupt descriptor and a
+                 * flag to say whether this interrupt pushes an error code onto
+                 * the stack as well: virtual interrupts never do. */
                 set_guest_interrupt(lg, idt->a, idt->b, 0);
         }
 }
 
+/*H:220 Now we've got the routines to deliver interrupts, delivering traps
+ * like page fault is easy.  The only trick is that Intel decided that some
+ * traps should have error codes: */
 static int has_err(unsigned int trap)
 {
         return (trap == 8 || (trap >= 10 && trap <= 14) || trap == 17);
 }
 
+/* deliver_trap() returns true if it could deliver the trap. */
 int deliver_trap(struct lguest *lg, unsigned int num)
 {
         u32 lo = lg->idt[num].a, hi = lg->idt[num].b;
 
+        /* Early on the Guest hasn't set the IDT entries (or maybe it put a
+         * bogus one in): if we fail here, the Guest will be killed. */
         if (!idt_present(lo, hi))
                 return 0;
         set_guest_interrupt(lg, lo, hi, has_err(num));
         return 1;
 }
 
+/*H:250 Here's the hard part: returning to the Host every time a trap happens
+ * and then calling deliver_trap() and re-entering the Guest is slow.
+ * Particularly because Guest userspace system calls are traps (trap 128).
+ *
+ * So we'd like to set up the IDT to tell the CPU to deliver traps directly
+ * into the Guest.  This is possible, but the complexities cause the size of
+ * this file to double!  However, 150 lines of code is worth writing for taking
+ * system calls down from 1750ns to 270ns.  Plus, if lguest didn't do it, all
+ * the other hypervisors would tease it.
+ *
+ * This routine determines if a trap can be delivered directly. */
 static int direct_trap(const struct lguest *lg,
                        const struct desc_struct *trap,
                        unsigned int num)
 {
-        /* Hardware interrupts don't go to guest (except syscall). */
+        /* Hardware interrupts don't go to the Guest at all (except system
+         * call). */
         if (num >= FIRST_EXTERNAL_VECTOR && num != SYSCALL_VECTOR)
                 return 0;
 
-        /* We intercept page fault (demand shadow paging & cr2 saving)
-           protection fault (in/out emulation) and device not
-           available (TS handling), and hypercall */
+        /* The Host needs to see page faults (for shadow paging and to save the
+         * fault address), general protection faults (in/out emulation) and
+         * device not available (TS handling), and of course, the hypercall
+         * trap. */
         if (num == 14 || num == 13 || num == 7 || num == LGUEST_TRAP_ENTRY)
                 return 0;
 
-        /* Interrupt gates (0xE) or not present (0x0) can't go direct. */
+        /* Only trap gates (type 15) can go direct to the Guest.  Interrupt
+         * gates (type 14) disable interrupts as they are entered, which we
+         * never let the Guest do.  Not present entries (type 0x0) also can't
+         * go direct, of course 8) */
         return idt_type(trap->a, trap->b) == 0xF;
 }
-
+/*:*/
+
+/*M:005 The Guest has the ability to turn its interrupt gates into trap gates,
+ * if it is careful.  The Host will let trap gates can go directly to the
+ * Guest, but the Guest needs the interrupts atomically disabled for an
+ * interrupt gate.  It can do this by pointing the trap gate at instructions
+ * within noirq_start and noirq_end, where it can safely disable interrupts. */
+
+/*M:006 The Guests do not use the sysenter (fast system call) instruction,
+ * because it's hardcoded to enter privilege level 0 and so can't go direct.
+ * It's about twice as fast as the older "int 0x80" system call, so it might
+ * still be worthwhile to handle it in the Switcher and lcall down to the
+ * Guest.  The sysenter semantics are hairy tho: search for that keyword in
+ * entry.S :*/
+
+/*H:260 When we make traps go directly into the Guest, we need to make sure
+ * the kernel stack is valid (ie. mapped in the page tables).  Otherwise, the
+ * CPU trying to deliver the trap will fault while trying to push the interrupt
+ * words on the stack: this is called a double fault, and it forces us to kill
+ * the Guest.
+ *
+ * Which is deeply unfair, because (literally!) it wasn't the Guests' fault. */
 void pin_stack_pages(struct lguest *lg)
 {
         unsigned int i;
 
+        /* Depending on the CONFIG_4KSTACKS option, the Guest can have one or
+         * two pages of stack space. */
         for (i = 0; i < lg->stack_pages; i++)
+                /* The stack grows *upwards*, hence the subtraction */
                 pin_page(lg, lg->esp1 - i * PAGE_SIZE);
 }
 
+/* Direct traps also mean that we need to know whenever the Guest wants to use
+ * a different kernel stack, so we can change the IDT entries to use that
+ * stack.  The IDT entries expect a virtual address, so unlike most addresses
+ * the Guest gives us, the "esp" (stack pointer) value here is virtual, not
+ * physical.
+ *
+ * In Linux each process has its own kernel stack, so this happens a lot: we
+ * change stacks on each context switch. */
 void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages)
 {
-        /* You cannot have a stack segment with priv level 0. */
+        /* You are not allowd have a stack segment with privilege level 0: bad
+         * Guest! */
         if ((seg & 0x3) != GUEST_PL)
                 kill_guest(lg, "bad stack segment %i", seg);
+        /* We only expect one or two stack pages. */
         if (pages > 2)
                 kill_guest(lg, "bad stack pages %u", pages);
+        /* Save where the stack is, and how many pages */
         lg->ss1 = seg;
         lg->esp1 = esp;
         lg->stack_pages = pages;
+        /* Make sure the new stack pages are mapped */
         pin_stack_pages(lg);
 }
 
-/* Set up trap in IDT. */
+/* All this reference to mapping stacks leads us neatly into the other complex
+ * part of the Host: page table handling. */
+
+/*H:235 This is the routine which actually checks the Guest's IDT entry and
+ * transfers it into our entry in "struct lguest": */
 static void set_trap(struct lguest *lg, struct desc_struct *trap,
                      unsigned int num, u32 lo, u32 hi)
 {
         u8 type = idt_type(lo, hi);
 
+        /* We zero-out a not-present entry */
         if (!idt_present(lo, hi)) {
                 trap->a = trap->b = 0;
                 return;
         }
 
+        /* We only support interrupt and trap gates. */
         if (type != 0xE && type != 0xF)
                 kill_guest(lg, "bad IDT type %i", type);
 
+        /* We only copy the handler address, present bit, privilege level and
+         * type.  The privilege level controls where the trap can be triggered
+         * manually with an "int" instruction.  This is usually GUEST_PL,
+         * except for system calls which userspace can use. */
         trap->a = ((__KERNEL_CS|GUEST_PL)<<16) | (lo&0x0000FFFF);
         trap->b = (hi&0xFFFFEF00);
 }
 
+/*H:230 While we're here, dealing with delivering traps and interrupts to the
+ * Guest, we might as well complete the picture: how the Guest tells us where
+ * it wants them to go.  This would be simple, except making traps fast
+ * requires some tricks.
+ *
+ * We saw the Guest setting Interrupt Descriptor Table (IDT) entries with the
+ * LHCALL_LOAD_IDT_ENTRY hypercall before: that comes here. */
 void load_guest_idt_entry(struct lguest *lg, unsigned int num, u32 lo, u32 hi)
 {
-        /* Guest never handles: NMI, doublefault, hypercall, spurious irq. */
+        /* Guest never handles: NMI, doublefault, spurious interrupt or
+         * hypercall.  We ignore when it tries to set them. */
         if (num == 2 || num == 8 || num == 15 || num == LGUEST_TRAP_ENTRY)
                 return;
 
+        /* Mark the IDT as changed: next time the Guest runs we'll know we have
+         * to copy this again. */
         lg->changed |= CHANGED_IDT;
+
+        /* The IDT which we keep in "struct lguest" only contains 32 entries
+         * for the traps and LGUEST_IRQS (32) entries for interrupts.  We
+         * ignore attempts to set handlers for higher interrupt numbers, except
+         * for the system call "interrupt" at 128: we have a special IDT entry
+         * for that. */
         if (num < ARRAY_SIZE(lg->idt))
                 set_trap(lg, &lg->idt[num], num, lo, hi);
         else if (num == SYSCALL_VECTOR)
                 set_trap(lg, &lg->syscall_idt, num, lo, hi);
 }
 
+/* The default entry for each interrupt points into the Switcher routines which
+ * simply return to the Host.  The run_guest() loop will then call
+ * deliver_trap() to bounce it back into the Guest. */
 static void default_idt_entry(struct desc_struct *idt,
                               int trap,
                               const unsigned long handler)
 {
+        /* A present interrupt gate. */
         u32 flags = 0x8e00;
 
-        /* They can't "int" into any of them except hypercall. */
+        /* Set the privilege level on the entry for the hypercall: this allows
+         * the Guest to use the "int" instruction to trigger it. */
         if (trap == LGUEST_TRAP_ENTRY)
                 flags |= (GUEST_PL << 13);
 
+        /* Now pack it into the IDT entry in its weird format. */
         idt->a = (LGUEST_CS<<16) | (handler&0x0000FFFF);
         idt->b = (handler&0xFFFF0000) | flags;
 }
 
+/* When the Guest first starts, we put default entries into the IDT. */
 void setup_default_idt_entries(struct lguest_ro_state *state,
                                const unsigned long *def)
 {
@@ -217,19 +376,25 @@ void setup_default_idt_entries(struct lguest_ro_state *state,
                 default_idt_entry(&state->guest_idt[i], i, def[i]);
 }
 
+/*H:240 We don't use the IDT entries in the "struct lguest" directly, instead
+ * we copy them into the IDT which we've set up for Guests on this CPU, just
+ * before we run the Guest.  This routine does that copy. */
 void copy_traps(const struct lguest *lg, struct desc_struct *idt,
                 const unsigned long *def)
 {
         unsigned int i;
 
-        /* All hardware interrupts are same whatever the guest: only the
-         * traps might be different. */
+        /* We can simply copy the direct traps, otherwise we use the default
+         * ones in the Switcher: they will return to the Host. */
         for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++) {
                 if (direct_trap(lg, &lg->idt[i], i))
                         idt[i] = lg->idt[i];
                 else
                         default_idt_entry(&idt[i], i, def[i]);
         }
+
+        /* Don't forget the system call trap!  The IDT entries for other
+         * interupts never change, so no need to copy them. */
         i = SYSCALL_VECTOR;
         if (direct_trap(lg, &lg->syscall_idt, i))
                 idt[i] = lg->syscall_idt;
diff --git a/drivers/lguest/io.c b/drivers/lguest/io.c
index c8eb79266991..ea68613b43f6 100644
--- a/drivers/lguest/io.c
+++ b/drivers/lguest/io.c
@@ -1,5 +1,9 @@
-/* Simple I/O model for guests, based on shared memory.
- * Copyright (C) 2006 Rusty Russell IBM Corporation
+/*P:300 The I/O mechanism in lguest is simple yet flexible, allowing the Guest
+ * to talk to the Launcher or directly to another Guest.  It uses familiar
+ * concepts of DMA and interrupts, plus some neat code stolen from
+ * futexes... :*/
+
+/* Copyright (C) 2006 Rusty Russell IBM Corporation
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -23,8 +27,36 @@
 #include <linux/uaccess.h>
 #include "lg.h"
 
+/*L:300
+ * I/O
+ *
+ * Getting data in and out of the Guest is quite an art.  There are numerous
+ * ways to do it, and they all suck differently.  We try to keep things fairly
+ * close to "real" hardware so our Guest's drivers don't look like an alien
+ * visitation in the middle of the Linux code, and yet make sure that Guests
+ * can talk directly to other Guests, not just the Launcher.
+ *
+ * To do this, the Guest gives us a key when it binds or sends DMA buffers.
+ * The key corresponds to a "physical" address inside the Guest (ie. a virtual
+ * address inside the Launcher process).  We don't, however, use this key
+ * directly.
+ *
+ * We want Guests which share memory to be able to DMA to each other: two
+ * Launchers can mmap memory the same file, then the Guests can communicate.
+ * Fortunately, the futex code provides us with a way to get a "union
+ * futex_key" corresponding to the memory lying at a virtual address: if the
+ * two processes share memory, the "union futex_key" for that memory will match
+ * even if the memory is mapped at different addresses in each.  So we always
+ * convert the keys to "union futex_key"s to compare them.
+ *
+ * Before we dive into this though, we need to look at another set of helper
+ * routines used throughout the Host kernel code to access Guest memory.
+ :*/
 static struct list_head dma_hash[61];
 
+/* An unfortunate side effect of the Linux double-linked list implementation is
+ * that there's no good way to statically initialize an array of linked
+ * lists. */
 void lguest_io_init(void)
 {
         unsigned int i;
@@ -56,6 +88,19 @@ kill:
         return 0;
 }
 
+/*L:330 This is our hash function, using the wonderful Jenkins hash.
+ *
+ * The futex key is a union with three parts: an unsigned long word, a pointer,
+ * and an int "offset".  We could use jhash_2words() which takes three u32s.
+ * (Ok, the hash functions are great: the naming sucks though).
+ *
+ * It's nice to be portable to 64-bit platforms, so we use the more generic
+ * jhash2(), which takes an array of u32, the number of u32s, and an initial
+ * u32 to roll in.  This is uglier, but breaks down to almost the same code on
+ * 32-bit platforms like this one.
+ *
+ * We want a position in the array, so we modulo ARRAY_SIZE(dma_hash) (ie. 61).
+ */
 static unsigned int hash(const union futex_key *key)
 {
         return jhash2((u32*)&key->both.word,
@@ -64,6 +109,9 @@ static unsigned int hash(const union futex_key *key)
                 % ARRAY_SIZE(dma_hash);
 }
 
+/* This is a convenience routine to compare two keys.  It's a much bemoaned C
+ * weakness that it doesn't allow '==' on structures or unions, so we have to
+ * open-code it like this. */
 static inline int key_eq(const union futex_key *a, const union futex_key *b)
 {
         return (a->both.word == b->both.word
@@ -71,22 +119,36 @@ static inline int key_eq(const union futex_key *a, const union futex_key *b)
                 && a->both.offset == b->both.offset);
 }
 
-/* Must hold read lock on dmainfo owner's current->mm->mmap_sem */
+/*L:360 OK, when we need to actually free up a Guest's DMA array we do several
+ * things, so we have a convenient function to do it.
+ *
+ * The caller must hold a read lock on dmainfo owner's current->mm->mmap_sem
+ * for the drop_futex_key_refs(). */
 static void unlink_dma(struct lguest_dma_info *dmainfo)
 {
+        /* You locked this too, right? */
         BUG_ON(!mutex_is_locked(&lguest_lock));
+        /* This is how we know that the entry is free. */
         dmainfo->interrupt = 0;
+        /* Remove it from the hash table. */
         list_del(&dmainfo->list);
+        /* Drop the references we were holding (to the inode or mm). */
         drop_futex_key_refs(&dmainfo->key);
 }
 
+/*L:350 This is the routine which we call when the Guest asks to unregister a
+ * DMA array attached to a given key.  Returns true if the array was found. */
 static int unbind_dma(struct lguest *lg,
                       const union futex_key *key,
                       unsigned long dmas)
 {
         int i, ret = 0;
 
+        /* We don't bother with the hash table, just look through all this
+         * Guest's DMA arrays. */
         for (i = 0; i < LGUEST_MAX_DMA; i++) {
+                /* In theory it could have more than one array on the same key,
+                 * or one array on multiple keys, so we check both */
                 if (key_eq(key, &lg->dma[i].key) && dmas == lg->dma[i].dmas) {
                         unlink_dma(&lg->dma[i]);
                         ret = 1;
@@ -96,51 +158,91 @@ static int unbind_dma(struct lguest *lg,
         return ret;
 }
 
+/*L:340 BIND_DMA: this is the hypercall which sets up an array of "struct
+ * lguest_dma" for receiving I/O.
+ *
+ * The Guest wants to bind an array of "struct lguest_dma"s to a particular key
+ * to receive input.  This only happens when the Guest is setting up a new
+ * device, so it doesn't have to be very fast.
+ *
+ * It returns 1 on a successful registration (it can fail if we hit the limit
+ * of registrations for this Guest).
+ */
 int bind_dma(struct lguest *lg,
              unsigned long ukey, unsigned long dmas, u16 numdmas, u8 interrupt)
 {
         unsigned int i;
         int ret = 0;
         union futex_key key;
+        /* Futex code needs the mmap_sem. */
         struct rw_semaphore *fshared = &current->mm->mmap_sem;
 
+        /* Invalid interrupt?  (We could kill the guest here). */
         if (interrupt >= LGUEST_IRQS)
                 return 0;
 
+        /* We need to grab the Big Lguest Lock, because other Guests may be
+         * trying to look through this Guest's DMAs to send something while
+         * we're doing this. */
         mutex_lock(&lguest_lock);
         down_read(fshared);
         if (get_futex_key((u32 __user *)ukey, fshared, &key) != 0) {
                 kill_guest(lg, "bad dma key %#lx", ukey);
                 goto unlock;
         }
+
+        /* We want to keep this key valid once we drop mmap_sem, so we have to
+         * hold a reference. */
         get_futex_key_refs(&key);
 
+        /* If the Guest specified an interrupt of 0, that means they want to
+         * unregister this array of "struct lguest_dma"s. */
         if (interrupt == 0)
                 ret = unbind_dma(lg, &key, dmas);
         else {
+                /* Look through this Guest's dma array for an unused entry. */
                 for (i = 0; i < LGUEST_MAX_DMA; i++) {
+                        /* If the interrupt is non-zero, the entry is already
+                         * used. */
                         if (lg->dma[i].interrupt)
                                 continue;
 
+                        /* OK, a free one!  Fill on our details. */
                         lg->dma[i].dmas = dmas;
                         lg->dma[i].num_dmas = numdmas;
                         lg->dma[i].next_dma = 0;
                         lg->dma[i].key = key;
                         lg->dma[i].guestid = lg->guestid;
                         lg->dma[i].interrupt = interrupt;
+
+                        /* Now we add it to the hash table: the position
+                         * depends on the futex key that we got. */
                         list_add(&lg->dma[i].list, &dma_hash[hash(&key)]);
+                        /* Success! */
                         ret = 1;
                         goto unlock;
                 }
         }
+        /* If we didn't find a slot to put the key in, drop the reference
+         * again. */
         drop_futex_key_refs(&key);
 unlock:
+        /* Unlock and out. */
         up_read(fshared);
         mutex_unlock(&lguest_lock);
         return ret;
 }
 
-/* lgread from another guest */
+/*L:385 Note that our routines to access a different Guest's memory are called
+ * lgread_other() and lgwrite_other(): these names emphasize that they are only
+ * used when the Guest is *not* the current Guest.
+ *
+ * The interface for copying from another process's memory is called
+ * access_process_vm(), with a final argument of 0 for a read, and 1 for a
+ * write.
+ *
+ * We need lgread_other() to read the destination Guest's "struct lguest_dma"
+ * array. */
 static int lgread_other(struct lguest *lg,
                         void *buf, u32 addr, unsigned bytes)
 {
@@ -153,7 +255,8 @@ static int lgread_other(struct lguest *lg,
         return 1;
 }
 
-/* lgwrite to another guest */
+/* "lgwrite()" to another Guest: used to update the destination "used_len" once
+ * we've transferred data into the buffer. */
 static int lgwrite_other(struct lguest *lg, u32 addr,
                          const void *buf, unsigned bytes)
 {
@@ -166,6 +269,15 @@ static int lgwrite_other(struct lguest *lg, u32 addr,
         return 1;
 }
 
+/*L:400 This is the generic engine which copies from a source "struct
+ * lguest_dma" from this Guest into another Guest's "struct lguest_dma".  The
+ * destination Guest's pages have already been mapped, as contained in the
+ * pages array.
+ *
+ * If you're wondering if there's a nice "copy from one process to another"
+ * routine, so was I.  But Linux isn't really set up to copy between two
+ * unrelated processes, so we have to write it ourselves.
+ */
 static u32 copy_data(struct lguest *srclg,
                      const struct lguest_dma *src,
                      const struct lguest_dma *dst,
@@ -174,33 +286,59 @@ static u32 copy_data(struct lguest *srclg,
         unsigned int totlen, si, di, srcoff, dstoff;
         void *maddr = NULL;
 
+        /* We return the total length transferred. */
         totlen = 0;
+
+        /* We keep indexes into the source and destination "struct lguest_dma",
+         * and an offset within each region. */
         si = di = 0;
         srcoff = dstoff = 0;
+
+        /* We loop until the source or destination is exhausted. */
         while (si < LGUEST_MAX_DMA_SECTIONS && src->len[si]
                && di < LGUEST_MAX_DMA_SECTIONS && dst->len[di]) {
+                /* We can only transfer the rest of the src buffer, or as much
+                 * as will fit into the destination buffer. */
                 u32 len = min(src->len[si] - srcoff, dst->len[di] - dstoff);
 
+                /* For systems using "highmem" we need to use kmap() to access
+                 * the page we want.  We often use the same page over and over,
+                 * so rather than kmap() it on every loop, we set the maddr
+                 * pointer to NULL when we need to move to the next
+                 * destination page. */
                 if (!maddr)
                         maddr = kmap(pages[di]);
 
-                /* FIXME: This is not completely portable, since
-                   archs do different things for copy_to_user_page. */
+                /* Copy directly from (this Guest's) source address to the
+                 * destination Guest's kmap()ed buffer.  Note that maddr points
+                 * to the start of the page: we need to add the offset of the
+                 * destination address and offset within the buffer. */
+
+                /* FIXME: This is not completely portable.  I looked at
+                 * copy_to_user_page(), and some arch's seem to need special
+                 * flushes.  x86 is fine. */
                 if (copy_from_user(maddr + (dst->addr[di] + dstoff)%PAGE_SIZE,
                                    (void __user *)src->addr[si], len) != 0) {
+                        /* If a copy failed, it's the source's fault. */
                         kill_guest(srclg, "bad address in sending DMA");
                         totlen = 0;
                         break;
                 }
 
+                /* Increment the total and src & dst offsets */
                 totlen += len;
                 srcoff += len;
                 dstoff += len;
+
+                /* Presumably we reached the end of the src or dest buffers: */
                 if (srcoff == src->len[si]) {
+                        /* Move to the next buffer at offset 0 */
                         si++;
                         srcoff = 0;
                 }
                 if (dstoff == dst->len[di]) {
+                        /* We need to unmap that destination page and reset
+                         * maddr ready for the next one. */
                         kunmap(pages[di]);
                         maddr = NULL;
                         di++;
@@ -208,13 +346,15 @@ static u32 copy_data(struct lguest *srclg,
                 }
         }
 
+        /* If we still had a page mapped at the end, unmap now. */
         if (maddr)
                 kunmap(pages[di]);
 
         return totlen;
 }
 
-/* Src is us, ie. current. */
+/*L:390 This is how we transfer a "struct lguest_dma" from the source Guest
+ * (the current Guest which called SEND_DMA) to another Guest. */
 static u32 do_dma(struct lguest *srclg, const struct lguest_dma *src,
                   struct lguest *dstlg, const struct lguest_dma *dst)
 {
@@ -222,23 +362,31 @@ static u32 do_dma(struct lguest *srclg, const struct lguest_dma *src,
         u32 ret;
         struct page *pages[LGUEST_MAX_DMA_SECTIONS];
 
+        /* We check that both source and destination "struct lguest_dma"s are
+         * within the bounds of the source and destination Guests */
         if (!check_dma_list(dstlg, dst) || !check_dma_list(srclg, src))
                 return 0;
 
-        /* First get the destination pages */
+        /* We need to map the pages which correspond to each parts of
+         * destination buffer. */
         for (i = 0; i < LGUEST_MAX_DMA_SECTIONS; i++) {
                 if (dst->len[i] == 0)
                         break;
+                /* get_user_pages() is a complicated function, especially since
+                 * we only want a single page.  But it works, and returns the
+                 * number of pages.  Note that we're holding the destination's
+                 * mmap_sem, as get_user_pages() requires. */
                 if (get_user_pages(dstlg->tsk, dstlg->mm,
                                    dst->addr[i], 1, 1, 1, pages+i, NULL)
                     != 1) {
+                        /* This means the destination gave us a bogus buffer */
                         kill_guest(dstlg, "Error mapping DMA pages");
                         ret = 0;
                         goto drop_pages;
                 }
         }
 
-        /* Now copy until we run out of src or dst. */
+        /* Now copy the data until we run out of src or dst. */
         ret = copy_data(srclg, src, dst, pages);
 
 drop_pages:
@@ -247,6 +395,11 @@ drop_pages:
         return ret;
 }
 
+/*L:380 Transferring data from one Guest to another is not as simple as I'd
+ * like.  We've found the "struct lguest_dma_info" bound to the same address as
+ * the send, we need to copy into it.
+ *
+ * This function returns true if the destination array was empty. */
 static int dma_transfer(struct lguest *srclg,
                         unsigned long udma,
                         struct lguest_dma_info *dst)
@@ -255,15 +408,23 @@ static int dma_transfer(struct lguest *srclg,
         struct lguest *dstlg;
         u32 i, dma = 0;
 
+        /* From the "struct lguest_dma_info" we found in the hash, grab the
+         * Guest. */
         dstlg = &lguests[dst->guestid];
-        /* Get our dma list. */
+        /* Read in the source "struct lguest_dma" handed to SEND_DMA. */
         lgread(srclg, &src_dma, udma, sizeof(src_dma));
 
-        /* We can't deadlock against them dmaing to us, because this
-         * is all under the lguest_lock. */
+        /* We need the destination's mmap_sem, and we already hold the source's
+         * mmap_sem for the futex key lookup.  Normally this would suggest that
+         * we could deadlock if the destination Guest was trying to send to
+         * this source Guest at the same time, which is another reason that all
+         * I/O is done under the big lguest_lock. */
         down_read(&dstlg->mm->mmap_sem);
 
+        /* Look through the destination DMA array for an available buffer. */
         for (i = 0; i < dst->num_dmas; i++) {
+                /* We keep a "next_dma" pointer which often helps us avoid
+                 * looking at lots of previously-filled entries. */
                 dma = (dst->next_dma + i) % dst->num_dmas;
                 if (!lgread_other(dstlg, &dst_dma,
                                   dst->dmas + dma * sizeof(struct lguest_dma),
@@ -273,30 +434,46 @@ static int dma_transfer(struct lguest *srclg,
                 if (!dst_dma.used_len)
                         break;
         }
+
+        /* If we found a buffer, we do the actual data copy. */
         if (i != dst->num_dmas) {
                 unsigned long used_lenp;
                 unsigned int ret;
 
                 ret = do_dma(srclg, &src_dma, dstlg, &dst_dma);
-                /* Put used length in src. */
+                /* Put used length in the source "struct lguest_dma"'s used_len
+                 * field.  It's a little tricky to figure out where that is,
+                 * though. */
                 lgwrite_u32(srclg,
                             udma+offsetof(struct lguest_dma, used_len), ret);
+                /* Tranferring 0 bytes is OK if the source buffer was empty. */
                 if (ret == 0 && src_dma.len[0] != 0)
                         goto fail;
 
-                /* Make sure destination sees contents before length. */
+                /* The destination Guest might be running on a different CPU:
+                 * we have to make sure that it will see the "used_len" field
+                 * change to non-zero *after* it sees the data we copied into
+                 * the buffer.  Hence a write memory barrier. */
                 wmb();
+                /* Figuring out where the destination's used_len field for this
+                 * "struct lguest_dma" in the array is also a little ugly. */
                 used_lenp = dst->dmas
                         + dma * sizeof(struct lguest_dma)
                         + offsetof(struct lguest_dma, used_len);
                 lgwrite_other(dstlg, used_lenp, &ret, sizeof(ret));
+                /* Move the cursor for next time. */
                 dst->next_dma++;
         }
         up_read(&dstlg->mm->mmap_sem);
 
-        /* Do this last so dst doesn't simply sleep on lock. */
+        /* We trigger the destination interrupt, even if the destination was
+         * empty and we didn't transfer anything: this gives them a chance to
+         * wake up and refill. */
         set_bit(dst->interrupt, dstlg->irqs_pending);
+        /* Wake up the destination process. */
         wake_up_process(dstlg->tsk);
+        /* If we passed the last "struct lguest_dma", the receive had no
+         * buffers left. */
         return i == dst->num_dmas;
 
 fail:
@@ -304,6 +481,8 @@ fail:
         return 0;
 }
 
+/*L:370 This is the counter-side to the BIND_DMA hypercall; the SEND_DMA
+ * hypercall.  We find out who's listening, and send to them. */
 void send_dma(struct lguest *lg, unsigned long ukey, unsigned long udma)
 {
         union futex_key key;
@@ -313,31 +492,43 @@ void send_dma(struct lguest *lg, unsigned long ukey, unsigned long udma)
 again:
         mutex_lock(&lguest_lock);
         down_read(fshared);
+        /* Get the futex key for the key the Guest gave us */
         if (get_futex_key((u32 __user *)ukey, fshared, &key) != 0) {
                 kill_guest(lg, "bad sending DMA key");
                 goto unlock;
         }
-        /* Shared mapping?  Look for other guests... */
+        /* Since the key must be a multiple of 4, the futex key uses the lower
+         * bit of the "offset" field (which would always be 0) to indicate a
+         * mapping which is shared with other processes (ie. Guests). */
         if (key.shared.offset & 1) {
                 struct lguest_dma_info *i;
+                /* Look through the hash for other Guests. */
                 list_for_each_entry(i, &dma_hash[hash(&key)], list) {
+                        /* Don't send to ourselves. */
                         if (i->guestid == lg->guestid)
                                 continue;
                         if (!key_eq(&key, &i->key))
                                 continue;
 
+                        /* If dma_transfer() tells us the destination has no
+                         * available buffers, we increment "empty". */
                         empty += dma_transfer(lg, udma, i);
                         break;
                 }
+                /* If the destination is empty, we release our locks and
+                 * give the destination Guest a brief chance to restock. */
                 if (empty == 1) {
                         /* Give any recipients one chance to restock. */
                         up_read(&current->mm->mmap_sem);
                         mutex_unlock(&lguest_lock);
+                        /* Next time, we won't try again. */
                         empty++;
                         goto again;
                 }
         } else {
-                /* Private mapping: tell our userspace. */
+                /* Private mapping: Guest is sending to its Launcher.  We set
+                 * the "dma_is_pending" flag so that the main loop will exit
+                 * and the Launcher's read() from /dev/lguest will return. */
                 lg->dma_is_pending = 1;
                 lg->pending_dma = udma;
                 lg->pending_key = ukey;
@@ -346,6 +537,7 @@ unlock:
         up_read(fshared);
         mutex_unlock(&lguest_lock);
 }
+/*:*/
 
 void release_all_dma(struct lguest *lg)
 {
@@ -361,7 +553,18 @@ void release_all_dma(struct lguest *lg)
         up_read(&lg->mm->mmap_sem);
 }
 
-/* Userspace wants a dma buffer from this guest. */
+/*M:007 We only return a single DMA buffer to the Launcher, but it would be
+ * more efficient to return a pointer to the entire array of DMA buffers, which
+ * it can cache and choose one whenever it wants.
+ *
+ * Currently the Launcher uses a write to /dev/lguest, and the return value is
+ * the address of the DMA structure with the interrupt number placed in
+ * dma->used_len.  If we wanted to return the entire array, we need to return
+ * the address, array size and interrupt number: this seems to require an
+ * ioctl(). :*/
+
+/*L:320 This routine looks for a DMA buffer registered by the Guest on the
+ * given key (using the BIND_DMA hypercall). */
 unsigned long get_dma_buffer(struct lguest *lg,
                              unsigned long ukey, unsigned long *interrupt)
 {
@@ -370,15 +573,29 @@ unsigned long get_dma_buffer(struct lguest *lg,
         struct lguest_dma_info *i;
         struct rw_semaphore *fshared = &current->mm->mmap_sem;
 
+        /* Take the Big Lguest Lock to stop other Guests sending this Guest DMA
+         * at the same time. */
         mutex_lock(&lguest_lock);
+        /* To match between Guests sharing the same underlying memory we steal
+         * code from the futex infrastructure.  This requires that we hold the
+         * "mmap_sem" for our process (the Launcher), and pass it to the futex
+         * code. */
         down_read(fshared);
+
+        /* This can fail if it's not a valid address, or if the address is not
+         * divisible by 4 (the futex code needs that, we don't really). */
         if (get_futex_key((u32 __user *)ukey, fshared, &key) != 0) {
                 kill_guest(lg, "bad registered DMA buffer");
                 goto unlock;
         }
+        /* Search the hash table for matching entries (the Launcher can only
+         * send to its own Guest for the moment, so the entry must be for this
+         * Guest) */
         list_for_each_entry(i, &dma_hash[hash(&key)], list) {
                 if (key_eq(&key, &i->key) && i->guestid == lg->guestid) {
                         unsigned int j;
+                        /* Look through the registered DMA array for an
+                         * available buffer. */
                         for (j = 0; j < i->num_dmas; j++) {
                                 struct lguest_dma dma;
 
@@ -387,6 +604,8 @@ unsigned long get_dma_buffer(struct lguest *lg,
                                 if (dma.used_len == 0)
                                         break;
                         }
+                        /* Store the interrupt the Guest wants when the buffer
+                         * is used. */
                         *interrupt = i->interrupt;
                         break;
                 }
@@ -396,4 +615,12 @@ unlock:
         mutex_unlock(&lguest_lock);
         return ret;
 }
+/*:*/
 
+/*L:410 This really has completed the Launcher.  Not only have we now finished
+ * the longest chapter in our journey, but this also means we are over halfway
+ * through!
+ *
+ * Enough prevaricating around the bush: it is time for us to dive into the
+ * core of the Host, in "make Host".
+ */
diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 3e2ddfbc816e..269116eee85f 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -58,9 +58,18 @@ struct lguest_dma_info
         u8 interrupt;   /* 0 when not registered */
 };
 
-/* We have separate types for the guest's ptes & pgds and the shadow ptes &
- * pgds.  Since this host might use three-level pagetables and the guest and
- * shadow pagetables don't, we can't use the normal pte_t/pgd_t. */
+/*H:310 The page-table code owes a great debt of gratitude to Andi Kleen.  He
+ * reviewed the original code which used "u32" for all page table entries, and
+ * insisted that it would be far clearer with explicit typing.  I thought it
+ * was overkill, but he was right: it is much clearer than it was before.
+ *
+ * We have separate types for the Guest's ptes & pgds and the shadow ptes &
+ * pgds.  There's already a Linux type for these (pte_t and pgd_t) but they
+ * change depending on kernel config options (PAE). */
+
+/* Each entry is identical: lower 12 bits of flags and upper 20 bits for the
+ * "page frame number" (0 == first physical page, etc).  They are different
+ * types so the compiler will warn us if we mix them improperly. */
 typedef union {
         struct { unsigned flags:12, pfn:20; };
         struct { unsigned long val; } raw;
@@ -77,8 +86,12 @@ typedef union {
         struct { unsigned flags:12, pfn:20; };
         struct { unsigned long val; } raw;
 } gpte_t;
+
+/* We have two convenient macros to convert a "raw" value as handed to us by
+ * the Guest into the correct Guest PGD or PTE type. */
 #define mkgpte(_val) ((gpte_t){.raw.val = _val})
 #define mkgpgd(_val) ((gpgd_t){.raw.val = _val})
+/*:*/
 
 struct pgdir
 {
@@ -244,6 +257,30 @@ unsigned long get_dma_buffer(struct lguest *lg, unsigned long key,
 /* hypercalls.c: */
 void do_hypercalls(struct lguest *lg);
 
+/*L:035
+ * Let's step aside for the moment, to study one important routine that's used
+ * widely in the Host code.
+ *
+ * There are many cases where the Guest does something invalid, like pass crap
+ * to a hypercall.  Since only the Guest kernel can make hypercalls, it's quite
+ * acceptable to simply terminate the Guest and give the Launcher a nicely
+ * formatted reason.  It's also simpler for the Guest itself, which doesn't
+ * need to check most hypercalls for "success"; if you're still running, it
+ * succeeded.
+ *
+ * Once this is called, the Guest will never run again, so most Host code can
+ * call this then continue as if nothing had happened.  This means many
+ * functions don't have to explicitly return an error code, which keeps the
+ * code simple.
+ *
+ * It also means that this can be called more than once: only the first one is
+ * remembered.  The only trick is that we still need to kill the Guest even if
+ * we can't allocate memory to store the reason.  Linux has a neat way of
+ * packing error codes into invalid pointers, so we use that here.
+ *
+ * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
+ * } while(0)".
+ */
 #define kill_guest(lg, fmt...)                                  \
 do {                                                            \
         if (!(lg)->dead) {                                      \
@@ -252,6 +289,7 @@ do {								\
                         (lg)->dead = ERR_PTR(-ENOMEM);          \
         }                                                       \
 } while(0)
+/* (End of aside) :*/
 
 static inline unsigned long guest_pa(struct lguest *lg, unsigned long vaddr)
 {
diff --git a/drivers/lguest/lguest.c b/drivers/lguest/lguest.c
index 18dade06d4a9..6dfe568523a2 100644
--- a/drivers/lguest/lguest.c
+++ b/drivers/lguest/lguest.c
@@ -1,6 +1,32 @@
-/*
- * Lguest specific paravirt-ops implementation
+/*P:010
+ * A hypervisor allows multiple Operating Systems to run on a single machine.
+ * To quote David Wheeler: "Any problem in computer science can be solved with
+ * another layer of indirection."
+ *
+ * We keep things simple in two ways.  First, we start with a normal Linux
+ * kernel and insert a module (lg.ko) which allows us to run other Linux
+ * kernels the same way we'd run processes.  We call the first kernel the Host,
+ * and the others the Guests.  The program which sets up and configures Guests
+ * (such as the example in Documentation/lguest/lguest.c) is called the
+ * Launcher.
+ *
+ * Secondly, we only run specially modified Guests, not normal kernels.  When
+ * you set CONFIG_LGUEST to 'y' or 'm', this automatically sets
+ * CONFIG_LGUEST_GUEST=y, which compiles this file into the kernel so it knows
+ * how to be a Guest.  This means that you can use the same kernel you boot
+ * normally (ie. as a Host) as a Guest.
  *
+ * These Guests know that they cannot do privileged operations, such as disable
+ * interrupts, and that they have to ask the Host to do such things explicitly.
+ * This file consists of all the replacements for such low-level native
+ * hardware operations: these special Guest versions call the Host.
+ *
+ * So how does the kernel know it's a Guest?  The Guest starts at a special
+ * entry point marked with a magic string, which sets up a few things then
+ * calls here.  We replace the native functions in "struct paravirt_ops"
+ * with our Guest versions, then boot like normal. :*/
+
+/*
  * Copyright (C) 2006, Rusty Russell <rusty@rustcorp.com.au> IBM Corporation.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -40,6 +66,12 @@
 #include <asm/mce.h>
 #include <asm/io.h>
 
+/*G:010 Welcome to the Guest!
+ *
+ * The Guest in our tale is a simple creature: identical to the Host but
+ * behaving in simplified but equivalent ways.  In particular, the Guest is the
+ * same kernel as the Host (or at least, built from the same source code). :*/
+
 /* Declarations for definitions in lguest_guest.S */
 extern char lguest_noirq_start[], lguest_noirq_end[];
 extern const char lgstart_cli[], lgend_cli[];
@@ -58,7 +90,26 @@ struct lguest_data lguest_data = {
 struct lguest_device_desc *lguest_devices;
 static cycle_t clock_base;
 
-static enum paravirt_lazy_mode lazy_mode;
+/*G:035 Notice the lazy_hcall() above, rather than hcall().  This is our first
+ * real optimization trick!
+ *
+ * When lazy_mode is set, it means we're allowed to defer all hypercalls and do
+ * them as a batch when lazy_mode is eventually turned off.  Because hypercalls
+ * are reasonably expensive, batching them up makes sense.  For example, a
+ * large mmap might update dozens of page table entries: that code calls
+ * lguest_lazy_mode(PARAVIRT_LAZY_MMU), does the dozen updates, then calls
+ * lguest_lazy_mode(PARAVIRT_LAZY_NONE).
+ *
+ * So, when we're in lazy mode, we call async_hypercall() to store the call for
+ * future processing.  When lazy mode is turned off we issue a hypercall to
+ * flush the stored calls.
+ *
+ * There's also a hack where "mode" is set to "PARAVIRT_LAZY_FLUSH" which
+ * indicates we're to flush any outstanding calls immediately.  This is used
+ * when an interrupt handler does a kmap_atomic(): the page table changes must
+ * happen immediately even if we're in the middle of a batch.  Usually we're
+ * not, though, so there's nothing to do. */
+static enum paravirt_lazy_mode lazy_mode; /* Note: not SMP-safe! */
 static void lguest_lazy_mode(enum paravirt_lazy_mode mode)
 {
         if (mode == PARAVIRT_LAZY_FLUSH) {
@@ -82,6 +133,16 @@ static void lazy_hcall(unsigned long call,
                 async_hcall(call, arg1, arg2, arg3);
 }
 
+/* async_hcall() is pretty simple: I'm quite proud of it really.  We have a
+ * ring buffer of stored hypercalls which the Host will run though next time we
+ * do a normal hypercall.  Each entry in the ring has 4 slots for the hypercall
+ * arguments, and a "hcall_status" word which is 0 if the call is ready to go,
+ * and 255 once the Host has finished with it.
+ *
+ * If we come around to a slot which hasn't been finished, then the table is
+ * full and we just make the hypercall directly.  This has the nice side
+ * effect of causing the Host to run all the stored calls in the ring buffer
+ * which empties it for next time! */
 void async_hcall(unsigned long call,
                  unsigned long arg1, unsigned long arg2, unsigned long arg3)
 {
@@ -89,6 +150,9 @@ void async_hcall(unsigned long call,
         static unsigned int next_call;
         unsigned long flags;
 
+        /* Disable interrupts if not already disabled: we don't want an
+         * interrupt handler making a hypercall while we're already doing
+         * one! */
         local_irq_save(flags);
         if (lguest_data.hcall_status[next_call] != 0xFF) {
                 /* Table full, so do normal hcall which will flush table. */
@@ -98,7 +162,7 @@ void async_hcall(unsigned long call,
                 lguest_data.hcalls[next_call].edx = arg1;
                 lguest_data.hcalls[next_call].ebx = arg2;
                 lguest_data.hcalls[next_call].ecx = arg3;
-                /* Make sure host sees arguments before "valid" flag. */
+                /* Arguments must all be written before we mark it to go */
                 wmb();
                 lguest_data.hcall_status[next_call] = 0;
                 if (++next_call == LHCALL_RING_SIZE)
@@ -106,9 +170,14 @@ void async_hcall(unsigned long call,
         }
         local_irq_restore(flags);
 }
+/*:*/
 
+/* Wrappers for the SEND_DMA and BIND_DMA hypercalls.  This is mainly because
+ * Jeff Garzik complained that __pa() should never appear in drivers, and this
+ * helps remove most of them.   But also, it wraps some ugliness. */
 void lguest_send_dma(unsigned long key, struct lguest_dma *dma)
 {
+        /* The hcall might not write this if something goes wrong */
         dma->used_len = 0;
         hcall(LHCALL_SEND_DMA, key, __pa(dma), 0);
 }
@@ -116,11 +185,16 @@ void lguest_send_dma(unsigned long key, struct lguest_dma *dma)
 int lguest_bind_dma(unsigned long key, struct lguest_dma *dmas,
                     unsigned int num, u8 irq)
 {
+        /* This is the only hypercall which actually wants 5 arguments, and we
+         * only support 4.  Fortunately the interrupt number is always less
+         * than 256, so we can pack it with the number of dmas in the final
+         * argument.  */
         if (!hcall(LHCALL_BIND_DMA, key, __pa(dmas), (num << 8) | irq))
                 return -ENOMEM;
         return 0;
 }
 
+/* Unbinding is the same hypercall as binding, but with 0 num & irq. */
 void lguest_unbind_dma(unsigned long key, struct lguest_dma *dmas)
 {
         hcall(LHCALL_BIND_DMA, key, __pa(dmas), 0);
@@ -138,35 +212,73 @@ void lguest_unmap(void *addr)
         iounmap((__force void __iomem *)addr);
 }
 
+/*G:033
+ * Here are our first native-instruction replacements: four functions for
+ * interrupt control.
+ *
+ * The simplest way of implementing these would be to have "turn interrupts
+ * off" and "turn interrupts on" hypercalls.  Unfortunately, this is too slow:
+ * these are by far the most commonly called functions of those we override.
+ *
+ * So instead we keep an "irq_enabled" field inside our "struct lguest_data",
+ * which the Guest can update with a single instruction.  The Host knows to
+ * check there when it wants to deliver an interrupt.
+ */
+
+/* save_flags() is expected to return the processor state (ie. "eflags").  The
+ * eflags word contains all kind of stuff, but in practice Linux only cares
+ * about the interrupt flag.  Our "save_flags()" just returns that. */
 static unsigned long save_fl(void)
 {
         return lguest_data.irq_enabled;
 }
 
+/* "restore_flags" just sets the flags back to the value given. */
 static void restore_fl(unsigned long flags)
 {
-        /* FIXME: Check if interrupt pending... */
         lguest_data.irq_enabled = flags;
 }
 
+/* Interrupts go off... */
 static void irq_disable(void)
 {
         lguest_data.irq_enabled = 0;
 }
 
+/* Interrupts go on... */
 static void irq_enable(void)
 {
-        /* FIXME: Check if interrupt pending... */
         lguest_data.irq_enabled = X86_EFLAGS_IF;
 }
-
+/*:*/
+/*M:003 Note that we don't check for outstanding interrupts when we re-enable
+ * them (or when we unmask an interrupt).  This seems to work for the moment,
+ * since interrupts are rare and we'll just get the interrupt on the next timer
+ * tick, but when we turn on CONFIG_NO_HZ, we should revisit this.  One way
+ * would be to put the "irq_enabled" field in a page by itself, and have the
+ * Host write-protect it when an interrupt comes in when irqs are disabled.
+ * There will then be a page fault as soon as interrupts are re-enabled. :*/
+
+/*G:034
+ * The Interrupt Descriptor Table (IDT).
+ *
+ * The IDT tells the processor what to do when an interrupt comes in.  Each
+ * entry in the table is a 64-bit descriptor: this holds the privilege level,
+ * address of the handler, and... well, who cares?  The Guest just asks the
+ * Host to make the change anyway, because the Host controls the real IDT.
+ */
 static void lguest_write_idt_entry(struct desc_struct *dt,
                                    int entrynum, u32 low, u32 high)
 {
+        /* Keep the local copy up to date. */
         write_dt_entry(dt, entrynum, low, high);
+        /* Tell Host about this new entry. */
         hcall(LHCALL_LOAD_IDT_ENTRY, entrynum, low, high);
 }
 
+/* Changing to a different IDT is very rare: we keep the IDT up-to-date every
+ * time it is written, so we can simply loop through all entries and tell the
+ * Host about them. */
 static void lguest_load_idt(const struct Xgt_desc_struct *desc)
 {
         unsigned int i;
@@ -176,12 +288,29 @@ static void lguest_load_idt(const struct Xgt_desc_struct *desc)
                 hcall(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b);
 }
 
+/*
+ * The Global Descriptor Table.
+ *
+ * The Intel architecture defines another table, called the Global Descriptor
+ * Table (GDT).  You tell the CPU where it is (and its size) using the "lgdt"
+ * instruction, and then several other instructions refer to entries in the
+ * table.  There are three entries which the Switcher needs, so the Host simply
+ * controls the entire thing and the Guest asks it to make changes using the
+ * LOAD_GDT hypercall.
+ *
+ * This is the opposite of the IDT code where we have a LOAD_IDT_ENTRY
+ * hypercall and use that repeatedly to load a new IDT.  I don't think it
+ * really matters, but wouldn't it be nice if they were the same?
+ */
 static void lguest_load_gdt(const struct Xgt_desc_struct *desc)
 {
         BUG_ON((desc->size+1)/8 != GDT_ENTRIES);
         hcall(LHCALL_LOAD_GDT, __pa(desc->address), GDT_ENTRIES, 0);
 }
 
+/* For a single GDT entry which changes, we do the lazy thing: alter our GDT,
+ * then tell the Host to reload the entire thing.  This operation is so rare
+ * that this naive implementation is reasonable. */
 static void lguest_write_gdt_entry(struct desc_struct *dt,
                                    int entrynum, u32 low, u32 high)
 {
@@ -189,19 +318,58 @@ static void lguest_write_gdt_entry(struct desc_struct *dt,
         hcall(LHCALL_LOAD_GDT, __pa(dt), GDT_ENTRIES, 0);
 }
 
+/* OK, I lied.  There are three "thread local storage" GDT entries which change
+ * on every context switch (these three entries are how glibc implements
+ * __thread variables).  So we have a hypercall specifically for this case. */
 static void lguest_load_tls(struct thread_struct *t, unsigned int cpu)
 {
         lazy_hcall(LHCALL_LOAD_TLS, __pa(&t->tls_array), cpu, 0);
 }
+/*:*/
 
+/*G:038 That's enough excitement for now, back to ploughing through each of
+ * the paravirt_ops (we're about 1/3 of the way through).
+ *
+ * This is the Local Descriptor Table, another weird Intel thingy.  Linux only
+ * uses this for some strange applications like Wine.  We don't do anything
+ * here, so they'll get an informative and friendly Segmentation Fault. */
 static void lguest_set_ldt(const void *addr, unsigned entries)
 {
 }
 
+/* This loads a GDT entry into the "Task Register": that entry points to a
+ * structure called the Task State Segment.  Some comments scattered though the
+ * kernel code indicate that this used for task switching in ages past, along
+ * with blood sacrifice and astrology.
+ *
+ * Now there's nothing interesting in here that we don't get told elsewhere.
+ * But the native version uses the "ltr" instruction, which makes the Host
+ * complain to the Guest about a Segmentation Fault and it'll oops.  So we
+ * override the native version with a do-nothing version. */
 static void lguest_load_tr_desc(void)
 {
 }
 
+/* The "cpuid" instruction is a way of querying both the CPU identity
+ * (manufacturer, model, etc) and its features.  It was introduced before the
+ * Pentium in 1993 and keeps getting extended by both Intel and AMD.  As you
+ * might imagine, after a decade and a half this treatment, it is now a giant
+ * ball of hair.  Its entry in the current Intel manual runs to 28 pages.
+ *
+ * This instruction even it has its own Wikipedia entry.  The Wikipedia entry
+ * has been translated into 4 languages.  I am not making this up!
+ *
+ * We could get funky here and identify ourselves as "GenuineLguest", but
+ * instead we just use the real "cpuid" instruction.  Then I pretty much turned
+ * off feature bits until the Guest booted.  (Don't say that: you'll damage
+ * lguest sales!)  Shut up, inner voice!  (Hey, just pointing out that this is
+ * hardly future proof.)  Noone's listening!  They don't like you anyway,
+ * parenthetic weirdo!
+ *
+ * Replacing the cpuid so we can turn features off is great for the kernel, but
+ * anyone (including userspace) can just use the raw "cpuid" instruction and
+ * the Host won't even notice since it isn't privileged.  So we try not to get
+ * too worked up about it. */
 static void lguest_cpuid(unsigned int *eax, unsigned int *ebx,
                          unsigned int *ecx, unsigned int *edx)
 {
@@ -214,21 +382,43 @@ static void lguest_cpuid(unsigned int *eax, unsigned int *ebx,
                 *ecx &= 0x00002201;
                 /* SSE, SSE2, FXSR, MMX, CMOV, CMPXCHG8B, FPU. */
                 *edx &= 0x07808101;
-                /* Host wants to know when we flush kernel pages: set PGE. */
+                /* The Host can do a nice optimization if it knows that the
+                 * kernel mappings (addresses above 0xC0000000 or whatever
+                 * PAGE_OFFSET is set to) haven't changed.  But Linux calls
+                 * flush_tlb_user() for both user and kernel mappings unless
+                 * the Page Global Enable (PGE) feature bit is set. */
                 *edx |= 0x00002000;
                 break;
         case 0x80000000:
                 /* Futureproof this a little: if they ask how much extended
-                 * processor information, limit it to known fields. */
+                 * processor information there is, limit it to known fields. */
                 if (*eax > 0x80000008)
                         *eax = 0x80000008;
                 break;
         }
 }
 
+/* Intel has four control registers, imaginatively named cr0, cr2, cr3 and cr4.
+ * I assume there's a cr1, but it hasn't bothered us yet, so we'll not bother
+ * it.  The Host needs to know when the Guest wants to change them, so we have
+ * a whole series of functions like read_cr0() and write_cr0().
+ *
+ * We start with CR0.  CR0 allows you to turn on and off all kinds of basic
+ * features, but Linux only really cares about one: the horrifically-named Task
+ * Switched (TS) bit at bit 3 (ie. 8)
+ *
+ * What does the TS bit do?  Well, it causes the CPU to trap (interrupt 7) if
+ * the floating point unit is used.  Which allows us to restore FPU state
+ * lazily after a task switch, and Linux uses that gratefully, but wouldn't a
+ * name like "FPUTRAP bit" be a little less cryptic?
+ *
+ * We store cr0 (and cr3) locally, because the Host never changes it.  The
+ * Guest sometimes wants to read it and we'd prefer not to bother the Host
+ * unnecessarily. */
 static unsigned long current_cr0, current_cr3;
 static void lguest_write_cr0(unsigned long val)
 {
+        /* 8 == TS bit. */
         lazy_hcall(LHCALL_TS, val & 8, 0, 0);
         current_cr0 = val;
 }
@@ -238,17 +428,25 @@ static unsigned long lguest_read_cr0(void)
         return current_cr0;
 }
 
+/* Intel provided a special instruction to clear the TS bit for people too cool
+ * to use write_cr0() to do it.  This "clts" instruction is faster, because all
+ * the vowels have been optimized out. */
 static void lguest_clts(void)
 {
         lazy_hcall(LHCALL_TS, 0, 0, 0);
         current_cr0 &= ~8U;
 }
 
+/* CR2 is the virtual address of the last page fault, which the Guest only ever
+ * reads.  The Host kindly writes this into our "struct lguest_data", so we
+ * just read it out of there. */
 static unsigned long lguest_read_cr2(void)
 {
         return lguest_data.cr2;
 }
 
+/* CR3 is the current toplevel pagetable page: the principle is the same as
+ * cr0.  Keep a local copy, and tell the Host when it changes. */
 static void lguest_write_cr3(unsigned long cr3)
 {
         lazy_hcall(LHCALL_NEW_PGTABLE, cr3, 0, 0);
@@ -260,7 +458,7 @@ static unsigned long lguest_read_cr3(void)
         return current_cr3;
 }
 
-/* Used to enable/disable PGE, but we don't care. */
+/* CR4 is used to enable and disable PGE, but we don't care. */
 static unsigned long lguest_read_cr4(void)
 {
         return 0;
@@ -270,6 +468,59 @@ static void lguest_write_cr4(unsigned long val)
 {
 }
 
+/*
+ * Page Table Handling.
+ *
+ * Now would be a good time to take a rest and grab a coffee or similarly
+ * relaxing stimulant.  The easy parts are behind us, and the trek gradually
+ * winds uphill from here.
+ *
+ * Quick refresher: memory is divided into "pages" of 4096 bytes each.  The CPU
+ * maps virtual addresses to physical addresses using "page tables".  We could
+ * use one huge index of 1 million entries: each address is 4 bytes, so that's
+ * 1024 pages just to hold the page tables.   But since most virtual addresses
+ * are unused, we use a two level index which saves space.  The CR3 register
+ * contains the physical address of the top level "page directory" page, which
+ * contains physical addresses of up to 1024 second-level pages.  Each of these
+ * second level pages contains up to 1024 physical addresses of actual pages,
+ * or Page Table Entries (PTEs).
+ *
+ * Here's a diagram, where arrows indicate physical addresses:
+ *
+ * CR3 ---> +---------+
+ *          |      --------->+---------+
+ *          |         |      | PADDR1  |
+ *        Top-level   |      | PADDR2  |
+ *        (PMD) page  |      |         |
+ *          |         |    Lower-level |
+ *          |         |    (PTE) page  |
+ *          |         |      |         |
+ *            ....               ....
+ *
+ * So to convert a virtual address to a physical address, we look up the top
+ * level, which points us to the second level, which gives us the physical
+ * address of that page.  If the top level entry was not present, or the second
+ * level entry was not present, then the virtual address is invalid (we
+ * say "the page was not mapped").
+ *
+ * Put another way, a 32-bit virtual address is divided up like so:
+ *
+ *  1 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
+ * |<---- 10 bits ---->|<---- 10 bits ---->|<------ 12 bits ------>|
+ *    Index into top     Index into second      Offset within page
+ *  page directory page    pagetable page
+ *
+ * The kernel spends a lot of time changing both the top-level page directory
+ * and lower-level pagetable pages.  The Guest doesn't know physical addresses,
+ * so while it maintains these page tables exactly like normal, it also needs
+ * to keep the Host informed whenever it makes a change: the Host will create
+ * the real page tables based on the Guests'.
+ */
+
+/* The Guest calls this to set a second-level entry (pte), ie. to map a page
+ * into a process' address space.  We set the entry then tell the Host the
+ * toplevel and address this corresponds to.  The Guest uses one pagetable per
+ * process, so we need to tell the Host which one we're changing (mm->pgd). */
 static void lguest_set_pte_at(struct mm_struct *mm, unsigned long addr,
                               pte_t *ptep, pte_t pteval)
 {
@@ -277,7 +528,9 @@ static void lguest_set_pte_at(struct mm_struct *mm, unsigned long addr,
         lazy_hcall(LHCALL_SET_PTE, __pa(mm->pgd), addr, pteval.pte_low);
 }
 
-/* We only support two-level pagetables at the moment. */
+/* The Guest calls this to set a top-level entry.  Again, we set the entry then
+ * tell the Host which top-level page we changed, and the index of the entry we
+ * changed. */
 static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
 {
         *pmdp = pmdval;
@@ -285,7 +538,15 @@ static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
                    (__pa(pmdp)&(PAGE_SIZE-1))/4, 0);
 }
 
-/* FIXME: Eliminate all callers of this. */
+/* There are a couple of legacy places where the kernel sets a PTE, but we
+ * don't know the top level any more.  This is useless for us, since we don't
+ * know which pagetable is changing or what address, so we just tell the Host
+ * to forget all of them.  Fortunately, this is very rare.
+ *
+ * ... except in early boot when the kernel sets up the initial pagetables,
+ * which makes booting astonishingly slow.  So we don't even tell the Host
+ * anything changed until we've done the first page table switch.
+ */
 static void lguest_set_pte(pte_t *ptep, pte_t pteval)
 {
         *ptep = pteval;
@@ -294,22 +555,51 @@ static void lguest_set_pte(pte_t *ptep, pte_t pteval)
                 lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
 }
 
+/* Unfortunately for Lguest, the paravirt_ops for page tables were based on
+ * native page table operations.  On native hardware you can set a new page
+ * table entry whenever you want, but if you want to remove one you have to do
+ * a TLB flush (a TLB is a little cache of page table entries kept by the CPU).
+ *
+ * So the lguest_set_pte_at() and lguest_set_pmd() functions above are only
+ * called when a valid entry is written, not when it's removed (ie. marked not
+ * present).  Instead, this is where we come when the Guest wants to remove a
+ * page table entry: we tell the Host to set that entry to 0 (ie. the present
+ * bit is zero). */
 static void lguest_flush_tlb_single(unsigned long addr)
 {
-        /* Simply set it to zero, and it will fault back in. */
+        /* Simply set it to zero: if it was not, it will fault back in. */
         lazy_hcall(LHCALL_SET_PTE, current_cr3, addr, 0);
 }
 
+/* This is what happens after the Guest has removed a large number of entries.
+ * This tells the Host that any of the page table entries for userspace might
+ * have changed, ie. virtual addresses below PAGE_OFFSET. */
 static void lguest_flush_tlb_user(void)
 {
         lazy_hcall(LHCALL_FLUSH_TLB, 0, 0, 0);
 }
 
+/* This is called when the kernel page tables have changed.  That's not very
+ * common (unless the Guest is using highmem, which makes the Guest extremely
+ * slow), so it's worth separating this from the user flushing above. */
 static void lguest_flush_tlb_kernel(void)
 {
         lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
 }
 
+/*
+ * The Unadvanced Programmable Interrupt Controller.
+ *
+ * This is an attempt to implement the simplest possible interrupt controller.
+ * I spent some time looking though routines like set_irq_chip_and_handler,
+ * set_irq_chip_and_handler_name, set_irq_chip_data and set_phasers_to_stun and
+ * I *think* this is as simple as it gets.
+ *
+ * We can tell the Host what interrupts we want blocked ready for using the
+ * lguest_data.interrupts bitmap, so disabling (aka "masking") them is as
+ * simple as setting a bit.  We don't actually "ack" interrupts as such, we
+ * just mask and unmask them.  I wonder if we should be cleverer?
+ */
 static void disable_lguest_irq(unsigned int irq)
 {
         set_bit(irq, lguest_data.blocked_interrupts);
@@ -318,9 +608,9 @@ static void disable_lguest_irq(unsigned int irq)
 static void enable_lguest_irq(unsigned int irq)
 {
         clear_bit(irq, lguest_data.blocked_interrupts);
-        /* FIXME: If it's pending? */
 }
 
+/* This structure describes the lguest IRQ controller. */
 static struct irq_chip lguest_irq_controller = {
         .name           = "lguest",
         .mask           = disable_lguest_irq,
@@ -328,6 +618,10 @@ static struct irq_chip lguest_irq_controller = {
         .unmask         = enable_lguest_irq,
 };
 
+/* This sets up the Interrupt Descriptor Table (IDT) entry for each hardware
+ * interrupt (except 128, which is used for system calls), and then tells the
+ * Linux infrastructure that each interrupt is controlled by our level-based
+ * lguest interrupt controller. */
 static void __init lguest_init_IRQ(void)
 {
         unsigned int i;
@@ -340,14 +634,24 @@ static void __init lguest_init_IRQ(void)
                                                  handle_level_irq);
                 }
         }
+        /* This call is required to set up for 4k stacks, where we have
+         * separate stacks for hard and soft interrupts. */
         irq_ctx_init(smp_processor_id());
 }
 
+/*
+ * Time.
+ *
+ * It would be far better for everyone if the Guest had its own clock, but
+ * until then it must ask the Host for the time.
+ */
 static unsigned long lguest_get_wallclock(void)
 {
         return hcall(LHCALL_GET_WALLCLOCK, 0, 0, 0);
 }
 
+/* If the Host tells us we can trust the TSC, we use that, otherwise we simply
+ * use the imprecise but reliable "jiffies" counter. */
 static cycle_t lguest_clock_read(void)
 {
         if (lguest_data.tsc_khz)
@@ -428,12 +732,19 @@ static void lguest_time_irq(unsigned int irq, struct irq_desc *desc)
         local_irq_restore(flags);
 }
 
+/* At some point in the boot process, we get asked to set up our timing
+ * infrastructure.  The kernel doesn't expect timer interrupts before this, but
+ * we cleverly initialized the "blocked_interrupts" field of "struct
+ * lguest_data" so that timer interrupts were blocked until now. */
 static void lguest_time_init(void)
 {
+        /* Set up the timer interrupt (0) to go to our simple timer routine */
         set_irq_handler(0, lguest_time_irq);
 
-        /* We use the TSC if the Host tells us we can, otherwise a dumb
-         * jiffies-based clock. */
+        /* Our clock structure look like arch/i386/kernel/tsc.c if we can use
+         * the TSC, otherwise it looks like kernel/time/jiffies.c.  Either way,
+         * the "rating" is initialized so high that it's always chosen over any
+         * other clocksource. */
         if (lguest_data.tsc_khz) {
                 lguest_clock.shift = 22;
                 lguest_clock.mult = clocksource_khz2mult(lguest_data.tsc_khz,
@@ -449,13 +760,30 @@ static void lguest_time_init(void)
         clock_base = lguest_clock_read();
         clocksource_register(&lguest_clock);
 
-        /* We can't set cpumask in the initializer: damn C limitations! */
+        /* We can't set cpumask in the initializer: damn C limitations!  Set it
+         * here and register our timer device. */
         lguest_clockevent.cpumask = cpumask_of_cpu(0);
         clockevents_register_device(&lguest_clockevent);
 
+        /* Finally, we unblock the timer interrupt. */
         enable_lguest_irq(0);
 }
 
+/*
+ * Miscellaneous bits and pieces.
+ *
+ * Here is an oddball collection of functions which the Guest needs for things
+ * to work.  They're pretty simple.
+ */
+
+/* The Guest needs to tell the host what stack it expects traps to use.  For
+ * native hardware, this is part of the Task State Segment mentioned above in
+ * lguest_load_tr_desc(), but to help hypervisors there's this special call.
+ *
+ * We tell the Host the segment we want to use (__KERNEL_DS is the kernel data
+ * segment), the privilege level (we're privilege level 1, the Host is 0 and
+ * will not tolerate us trying to use that), the stack pointer, and the number
+ * of pages in the stack. */
 static void lguest_load_esp0(struct tss_struct *tss,
                                      struct thread_struct *thread)
 {
@@ -463,15 +791,31 @@ static void lguest_load_esp0(struct tss_struct *tss,
                    THREAD_SIZE/PAGE_SIZE);
 }
 
+/* Let's just say, I wouldn't do debugging under a Guest. */
 static void lguest_set_debugreg(int regno, unsigned long value)
 {
         /* FIXME: Implement */
 }
 
+/* There are times when the kernel wants to make sure that no memory writes are
+ * caught in the cache (that they've all reached real hardware devices).  This
+ * doesn't matter for the Guest which has virtual hardware.
+ *
+ * On the Pentium 4 and above, cpuid() indicates that the Cache Line Flush
+ * (clflush) instruction is available and the kernel uses that.  Otherwise, it
+ * uses the older "Write Back and Invalidate Cache" (wbinvd) instruction.
+ * Unlike clflush, wbinvd can only be run at privilege level 0.  So we can
+ * ignore clflush, but replace wbinvd.
+ */
 static void lguest_wbinvd(void)
 {
 }
 
+/* If the Guest expects to have an Advanced Programmable Interrupt Controller,
+ * we play dumb by ignoring writes and returning 0 for reads.  So it's no
+ * longer Programmable nor Controlling anything, and I don't think 8 lines of
+ * code qualifies for Advanced.  It will also never interrupt anything.  It
+ * does, however, allow us to get through the Linux boot code. */
 #ifdef CONFIG_X86_LOCAL_APIC
 static void lguest_apic_write(unsigned long reg, unsigned long v)
 {
@@ -483,19 +827,32 @@ static unsigned long lguest_apic_read(unsigned long reg)
 }
 #endif
 
+/* STOP!  Until an interrupt comes in. */
 static void lguest_safe_halt(void)
 {
         hcall(LHCALL_HALT, 0, 0, 0);
 }
 
+/* Perhaps CRASH isn't the best name for this hypercall, but we use it to get a
+ * message out when we're crashing as well as elegant termination like powering
+ * off.
+ *
+ * Note that the Host always prefers that the Guest speak in physical addresses
+ * rather than virtual addresses, so we use __pa() here. */
 static void lguest_power_off(void)
 {
         hcall(LHCALL_CRASH, __pa("Power down"), 0, 0);
 }
 
+/*
+ * Panicing.
+ *
+ * Don't.  But if you did, this is what happens.
+ */
 static int lguest_panic(struct notifier_block *nb, unsigned long l, void *p)
 {
         hcall(LHCALL_CRASH, __pa(p), 0, 0);
+        /* The hcall won't return, but to keep gcc happy, we're "done". */
         return NOTIFY_DONE;
 }
 
@@ -503,15 +860,45 @@ static struct notifier_block paniced = {
         .notifier_call = lguest_panic
 };
 
+/* Setting up memory is fairly easy. */
 static __init char *lguest_memory_setup(void)
 {
-        /* We do this here because lockcheck barfs if before start_kernel */
+        /* We do this here and not earlier because lockcheck barfs if we do it
+         * before start_kernel() */
         atomic_notifier_chain_register(&panic_notifier_list, &paniced);
 
+        /* The Linux bootloader header contains an "e820" memory map: the
+         * Launcher populated the first entry with our memory limit. */
         add_memory_region(E820_MAP->addr, E820_MAP->size, E820_MAP->type);
+
+        /* This string is for the boot messages. */
         return "LGUEST";
 }
 
+/*G:050
+ * Patching (Powerfully Placating Performance Pedants)
+ *
+ * We have already seen that "struct paravirt_ops" lets us replace simple
+ * native instructions with calls to the appropriate back end all throughout
+ * the kernel.  This allows the same kernel to run as a Guest and as a native
+ * kernel, but it's slow because of all the indirect branches.
+ *
+ * Remember that David Wheeler quote about "Any problem in computer science can
+ * be solved with another layer of indirection"?  The rest of that quote is
+ * "... But that usually will create another problem."  This is the first of
+ * those problems.
+ *
+ * Our current solution is to allow the paravirt back end to optionally patch
+ * over the indirect calls to replace them with something more efficient.  We
+ * patch the four most commonly called functions: disable interrupts, enable
+ * interrupts, restore interrupts and save interrupts.  We usually have 10
+ * bytes to patch into: the Guest versions of these operations are small enough
+ * that we can fit comfortably.
+ *
+ * First we need assembly templates of each of the patchable Guest operations,
+ * and these are in lguest_asm.S. */
+
+/*G:060 We construct a table from the assembler templates: */
 static const struct lguest_insns
 {
         const char *start, *end;
@@ -521,35 +908,52 @@ static const struct lguest_insns
         [PARAVIRT_PATCH(restore_fl)] = { lgstart_popf, lgend_popf },
         [PARAVIRT_PATCH(save_fl)] = { lgstart_pushf, lgend_pushf },
 };
+
+/* Now our patch routine is fairly simple (based on the native one in
+ * paravirt.c).  If we have a replacement, we copy it in and return how much of
+ * the available space we used. */
 static unsigned lguest_patch(u8 type, u16 clobber, void *insns, unsigned len)
 {
         unsigned int insn_len;
 
-        /* Don't touch it if we don't have a replacement */
+        /* Don't do anything special if we don't have a replacement */
         if (type >= ARRAY_SIZE(lguest_insns) || !lguest_insns[type].start)
                 return paravirt_patch_default(type, clobber, insns, len);
 
         insn_len = lguest_insns[type].end - lguest_insns[type].start;
 
-        /* Similarly if we can't fit replacement. */
+        /* Similarly if we can't fit replacement (shouldn't happen, but let's
+         * be thorough). */
         if (len < insn_len)
                 return paravirt_patch_default(type, clobber, insns, len);
 
+        /* Copy in our instructions. */
         memcpy(insns, lguest_insns[type].start, insn_len);
         return insn_len;
 }
 
+/*G:030 Once we get to lguest_init(), we know we're a Guest.  The paravirt_ops
+ * structure in the kernel provides a single point for (almost) every routine
+ * we have to override to avoid privileged instructions. */
 __init void lguest_init(void *boot)
 {
-        /* Copy boot parameters first. */
+        /* Copy boot parameters first: the Launcher put the physical location
+         * in %esi, and head.S converted that to a virtual address and handed
+         * it to us. */
         memcpy(&boot_params, boot, PARAM_SIZE);
+        /* The boot parameters also tell us where the command-line is: save
+         * that, too. */
         memcpy(boot_command_line, __va(boot_params.hdr.cmd_line_ptr),
                COMMAND_LINE_SIZE);
 
+        /* We're under lguest, paravirt is enabled, and we're running at
+         * privilege level 1, not 0 as normal. */
         paravirt_ops.name = "lguest";
         paravirt_ops.paravirt_enabled = 1;
         paravirt_ops.kernel_rpl = 1;
 
+        /* We set up all the lguest overrides for sensitive operations.  These
+         * are detailed with the operations themselves. */
         paravirt_ops.save_fl = save_fl;
         paravirt_ops.restore_fl = restore_fl;
         paravirt_ops.irq_disable = irq_disable;
@@ -593,20 +997,45 @@ __init void lguest_init(void *boot)
         paravirt_ops.set_lazy_mode = lguest_lazy_mode;
         paravirt_ops.wbinvd = lguest_wbinvd;
         paravirt_ops.sched_clock = lguest_sched_clock;
-
+        /* Now is a good time to look at the implementations of these functions
+         * before returning to the rest of lguest_init(). */
+
+        /*G:070 Now we've seen all the paravirt_ops, we return to
+         * lguest_init() where the rest of the fairly chaotic boot setup
+         * occurs.
+         *
+         * The Host expects our first hypercall to tell it where our "struct
+         * lguest_data" is, so we do that first. */
         hcall(LHCALL_LGUEST_INIT, __pa(&lguest_data), 0, 0);
 
-        /* We use top of mem for initial pagetables. */
+        /* The native boot code sets up initial page tables immediately after
+         * the kernel itself, and sets init_pg_tables_end so they're not
+         * clobbered.  The Launcher places our initial pagetables somewhere at
+         * the top of our physical memory, so we don't need extra space: set
+         * init_pg_tables_end to the end of the kernel. */
         init_pg_tables_end = __pa(pg0);
 
+        /* Load the %fs segment register (the per-cpu segment register) with
+         * the normal data segment to get through booting. */
         asm volatile ("mov %0, %%fs" : : "r" (__KERNEL_DS) : "memory");
 
+        /* The Host uses the top of the Guest's virtual address space for the
+         * Host<->Guest Switcher, and it tells us how much it needs in
+         * lguest_data.reserve_mem, set up on the LGUEST_INIT hypercall. */
         reserve_top_address(lguest_data.reserve_mem);
 
+        /* If we don't initialize the lock dependency checker now, it crashes
+         * paravirt_disable_iospace. */
         lockdep_init();
 
+        /* The IDE code spends about 3 seconds probing for disks: if we reserve
+         * all the I/O ports up front it can't get them and so doesn't probe.
+         * Other device drivers are similar (but less severe).  This cuts the
+         * kernel boot time on my machine from 4.1 seconds to 0.45 seconds. */
         paravirt_disable_iospace();
 
+        /* This is messy CPU setup stuff which the native boot code does before
+         * start_kernel, so we have to do, too: */
         cpu_detect(&new_cpu_data);
         /* head.S usually sets up the first capability word, so do it here. */
         new_cpu_data.x86_capability[0] = cpuid_edx(1);
@@ -617,14 +1046,27 @@ __init void lguest_init(void *boot)
 #ifdef CONFIG_X86_MCE
         mce_disabled = 1;
 #endif
-
 #ifdef CONFIG_ACPI
         acpi_disabled = 1;
         acpi_ht = 0;
 #endif
 
+        /* We set the perferred console to "hvc".  This is the "hypervisor
+         * virtual console" driver written by the PowerPC people, which we also
+         * adapted for lguest's use. */
         add_preferred_console("hvc", 0, NULL);
 
+        /* Last of all, we set the power management poweroff hook to point to
+         * the Guest routine to power off. */
         pm_power_off = lguest_power_off;
+
+        /* Now we're set up, call start_kernel() in init/main.c and we proceed
+         * to boot as normal.  It never returns. */
         start_kernel();
 }
+/*
+ * This marks the end of stage II of our journey, The Guest.
+ *
+ * It is now time for us to explore the nooks and crannies of the three Guest
+ * devices and complete our understanding of the Guest in "make Drivers".
+ */
diff --git a/drivers/lguest/lguest_asm.S b/drivers/lguest/lguest_asm.S
index a3dbf22ee365..f182c6a36209 100644
--- a/drivers/lguest/lguest_asm.S
+++ b/drivers/lguest/lguest_asm.S
@@ -4,15 +4,15 @@
 #include <asm/thread_info.h>
 #include <asm/processor-flags.h>
 
-/*
- * This is where we begin: we have a magic signature which the launcher looks
- * for.  The plan is that the Linux boot protocol will be extended with a
+/*G:020 This is where we begin: we have a magic signature which the launcher
+ * looks for.  The plan is that the Linux boot protocol will be extended with a
  * "platform type" field which will guide us here from the normal entry point,
- * but for the moment this suffices.  We pass the virtual address of the boot
- * info to lguest_init().
+ * but for the moment this suffices.  The normal boot code uses %esi for the
+ * boot header, so we do too.  We convert it to a virtual address by adding
+ * PAGE_OFFSET, and hand it to lguest_init() as its argument (ie. %eax).
  *
- * We put it in .init.text will be discarded after boot.
- */
+ * The .section line puts this code in .init.text so it will be discarded after
+ * boot. */
 .section .init.text, "ax", @progbits
 .ascii "GenuineLguest"
         /* Set up initial stack. */
@@ -21,7 +21,9 @@
         addl $__PAGE_OFFSET, %eax
         jmp lguest_init
 
-/* The templates for inline patching. */
+/*G:055 We create a macro which puts the assembler code between lgstart_ and
+ * lgend_ markers.  These templates end up in the .init.text section, so they
+ * are discarded after boot. */
 #define LGUEST_PATCH(name, insns...)                    \
         lgstart_##name: insns; lgend_##name:;           \
         .globl lgstart_##name; .globl lgend_##name
@@ -30,24 +32,61 @@ LGUEST_PATCH(cli, movl $0, lguest_data+LGUEST_DATA_irq_enabled)
 LGUEST_PATCH(sti, movl $X86_EFLAGS_IF, lguest_data+LGUEST_DATA_irq_enabled)
 LGUEST_PATCH(popf, movl %eax, lguest_data+LGUEST_DATA_irq_enabled)
 LGUEST_PATCH(pushf, movl lguest_data+LGUEST_DATA_irq_enabled, %eax)
+/*:*/
 
 .text
 /* These demark the EIP range where host should never deliver interrupts. */
 .global lguest_noirq_start
 .global lguest_noirq_end
 
-/*
- * We move eflags word to lguest_data.irq_enabled to restore interrupt state.
- * For page faults, gpfs and virtual interrupts, the hypervisor has saved
- * eflags manually, otherwise it was delivered directly and so eflags reflects
- * the real machine IF state, ie. interrupts on.  Since the kernel always dies
- * if it takes such a trap with interrupts disabled anyway, turning interrupts
- * back on unconditionally here is OK.
- */
+/*M:004 When the Host reflects a trap or injects an interrupt into the Guest,
+ * it sets the eflags interrupt bit on the stack based on
+ * lguest_data.irq_enabled, so the Guest iret logic does the right thing when
+ * restoring it.  However, when the Host sets the Guest up for direct traps,
+ * such as system calls, the processor is the one to push eflags onto the
+ * stack, and the interrupt bit will be 1 (in reality, interrupts are always
+ * enabled in the Guest).
+ *
+ * This turns out to be harmless: the only trap which should happen under Linux
+ * with interrupts disabled is Page Fault (due to our lazy mapping of vmalloc
+ * regions), which has to be reflected through the Host anyway.  If another
+ * trap *does* go off when interrupts are disabled, the Guest will panic, and
+ * we'll never get to this iret! :*/
+
+/*G:045 There is one final paravirt_op that the Guest implements, and glancing
+ * at it you can see why I left it to last.  It's *cool*!  It's in *assembler*!
+ *
+ * The "iret" instruction is used to return from an interrupt or trap.  The
+ * stack looks like this:
+ *   old address
+ *   old code segment & privilege level
+ *   old processor flags ("eflags")
+ *
+ * The "iret" instruction pops those values off the stack and restores them all
+ * at once.  The only problem is that eflags includes the Interrupt Flag which
+ * the Guest can't change: the CPU will simply ignore it when we do an "iret".
+ * So we have to copy eflags from the stack to lguest_data.irq_enabled before
+ * we do the "iret".
+ *
+ * There are two problems with this: firstly, we need to use a register to do
+ * the copy and secondly, the whole thing needs to be atomic.  The first
+ * problem is easy to solve: push %eax on the stack so we can use it, and then
+ * restore it at the end just before the real "iret".
+ *
+ * The second is harder: copying eflags to lguest_data.irq_enabled will turn
+ * interrupts on before we're finished, so we could be interrupted before we
+ * return to userspace or wherever.  Our solution to this is to surround the
+ * code with lguest_noirq_start: and lguest_noirq_end: labels.  We tell the
+ * Host that it is *never* to interrupt us there, even if interrupts seem to be
+ * enabled. */
 ENTRY(lguest_iret)
         pushl   %eax
         movl    12(%esp), %eax
 lguest_noirq_start:
+        /* Note the %ss: segment prefix here.  Normal data accesses use the
+         * "ds" segment, but that will have already been restored for whatever
+         * we're returning to (such as userspace): we can't trust it.  The %ss:
+         * prefix makes sure we use the stack segment, which is still valid. */
         movl    %eax,%ss:lguest_data+LGUEST_DATA_irq_enabled
         popl    %eax
         iret
diff --git a/drivers/lguest/lguest_bus.c b/drivers/lguest/lguest_bus.c
index 18d6ab21a43b..55a7940ca732 100644
--- a/drivers/lguest/lguest_bus.c
+++ b/drivers/lguest/lguest_bus.c
@@ -1,3 +1,6 @@
+/*P:050 Lguest guests use a very simple bus for devices.  It's a simple array
+ * of device descriptors contained just above the top of normal memory.  The
+ * lguest bus is 80% tedious boilerplate code. :*/
 #include <linux/init.h>
 #include <linux/bootmem.h>
 #include <linux/lguest_bus.h>
@@ -43,6 +46,10 @@ static struct device_attribute lguest_dev_attrs[] = {
         __ATTR_NULL
 };
 
+/*D:130 The generic bus infrastructure requires a function which says whether a
+ * device matches a driver.  For us, it is simple: "struct lguest_driver"
+ * contains a "device_type" field which indicates what type of device it can
+ * handle, so we just cast the args and compare: */
 static int lguest_dev_match(struct device *_dev, struct device_driver *_drv)
 {
         struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
@@ -50,6 +57,7 @@ static int lguest_dev_match(struct device *_dev, struct device_driver *_drv)
 
         return (drv->device_type == lguest_devices[dev->index].type);
 }
+/*:*/
 
 struct lguest_bus {
         struct bus_type bus;
@@ -68,11 +76,24 @@ static struct lguest_bus lguest_bus = {
         }
 };
 
+/*D:140 This is the callback which occurs once the bus infrastructure matches
+ * up a device and driver, ie. in response to add_lguest_device() calling
+ * device_register(), or register_lguest_driver() calling driver_register().
+ *
+ * At the moment it's always the latter: the devices are added first, since
+ * scan_devices() is called from a "core_initcall", and the drivers themselves
+ * called later as a normal "initcall".  But it would work the other way too.
+ *
+ * So now we have the happy couple, we add the status bit to indicate that we
+ * found a driver.  If the driver truly loves the device, it will return
+ * happiness from its probe function (ok, perhaps this wasn't my greatest
+ * analogy), and we set the final "driver ok" bit so the Host sees it's all
+ * green. */
 static int lguest_dev_probe(struct device *_dev)
 {
         int ret;
-        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
-        struct lguest_driver *drv = container_of(dev->dev.driver,
+        struct lguest_device*dev = container_of(_dev,struct lguest_device,dev);
+        struct lguest_driver*drv = container_of(dev->dev.driver,
                                                 struct lguest_driver, drv);
 
         lguest_devices[dev->index].status |= LGUEST_DEVICE_S_DRIVER;
@@ -82,6 +103,10 @@ static int lguest_dev_probe(struct device *_dev)
         return ret;
 }
 
+/* The last part of the bus infrastructure is the function lguest drivers use
+ * to register themselves.  Firstly, we do nothing if there's no lguest bus
+ * (ie. this is not a Guest), otherwise we fill in the embedded generic "struct
+ * driver" fields and call the generic driver_register(). */
 int register_lguest_driver(struct lguest_driver *drv)
 {
         if (!lguest_devices)
@@ -94,12 +119,36 @@ int register_lguest_driver(struct lguest_driver *drv)
 
         return driver_register(&drv->drv);
 }
+
+/* At the moment we build all the drivers into the kernel because they're so
+ * simple: 8144 bytes for all three of them as I type this.  And as the console
+ * really needs to be built in, it's actually only 3527 bytes for the network
+ * and block drivers.
+ *
+ * If they get complex it will make sense for them to be modularized, so we
+ * need to explicitly export the symbol.
+ *
+ * I don't think non-GPL modules make sense, so it's a GPL-only export.
+ */
 EXPORT_SYMBOL_GPL(register_lguest_driver);
 
+/*D:120 This is the core of the lguest bus: actually adding a new device.
+ * It's a separate function because it's neater that way, and because an
+ * earlier version of the code supported hotplug and unplug.  They were removed
+ * early on because they were never used.
+ *
+ * As Andrew Tridgell says, "Untested code is buggy code".
+ *
+ * It's worth reading this carefully: we start with an index into the array of
+ * "struct lguest_device_desc"s indicating the device which is new: */
 static void add_lguest_device(unsigned int index)
 {
         struct lguest_device *new;
 
+        /* Each "struct lguest_device_desc" has a "status" field, which the
+         * Guest updates as the device is probed.  In the worst case, the Host
+         * can look at these bits to tell what part of device setup failed,
+         * even if the console isn't available. */
         lguest_devices[index].status |= LGUEST_DEVICE_S_ACKNOWLEDGE;
         new = kmalloc(sizeof(struct lguest_device), GFP_KERNEL);
         if (!new) {
@@ -108,12 +157,17 @@ static void add_lguest_device(unsigned int index)
                 return;
         }
 
+        /* The "struct lguest_device" setup is pretty straight-forward example
+         * code. */
         new->index = index;
         new->private = NULL;
         memset(&new->dev, 0, sizeof(new->dev));
         new->dev.parent = &lguest_bus.dev;
         new->dev.bus = &lguest_bus.bus;
         sprintf(new->dev.bus_id, "%u", index);
+
+        /* device_register() causes the bus infrastructure to look for a
+         * matching driver. */
         if (device_register(&new->dev) != 0) {
                 printk(KERN_EMERG "Cannot register lguest device %u\n", index);
                 lguest_devices[index].status |= LGUEST_DEVICE_S_FAILED;
@@ -121,6 +175,9 @@ static void add_lguest_device(unsigned int index)
         }
 }
 
+/*D:110 scan_devices() simply iterates through the device array.  The type 0
+ * is reserved to mean "no device", and anything else means we have found a
+ * device: add it. */
 static void scan_devices(void)
 {
         unsigned int i;
@@ -130,12 +187,23 @@ static void scan_devices(void)
                         add_lguest_device(i);
 }
 
+/*D:100 Fairly early in boot, lguest_bus_init() is called to set up the lguest
+ * bus.  We check that we are a Guest by checking paravirt_ops.name: there are
+ * other ways of checking, but this seems most obvious to me.
+ *
+ * So we can access the array of "struct lguest_device_desc"s easily, we map
+ * that memory and store the pointer in the global "lguest_devices".  Then we
+ * register the bus with the core.  Doing two registrations seems clunky to me,
+ * but it seems to be the correct sysfs incantation.
+ *
+ * Finally we call scan_devices() which adds all the devices found in the
+ * "struct lguest_device_desc" array. */
 static int __init lguest_bus_init(void)
 {
         if (strcmp(paravirt_ops.name, "lguest") != 0)
                 return 0;
 
-        /* Devices are in page above top of "normal" mem. */
+        /* Devices are in a single page above top of "normal" mem */
         lguest_devices = lguest_map(max_pfn<<PAGE_SHIFT, 1);
 
         if (bus_register(&lguest_bus.bus) != 0
@@ -145,4 +213,5 @@ static int __init lguest_bus_init(void)
         scan_devices();
         return 0;
 }
+/* Do this after core stuff, before devices. */
 postcore_initcall(lguest_bus_init);
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index e90d7a783daf..80d1b58c7698 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -1,36 +1,70 @@
-/* Userspace control of the guest, via /dev/lguest. */
+/*P:200 This contains all the /dev/lguest code, whereby the userspace launcher
+ * controls and communicates with the Guest.  For example, the first write will
+ * tell us the memory size, pagetable, entry point and kernel address offset.
+ * A read will run the Guest until a signal is pending (-EINTR), or the Guest
+ * does a DMA out to the Launcher.  Writes are also used to get a DMA buffer
+ * registered by the Guest and to send the Guest an interrupt. :*/
 #include <linux/uaccess.h>
 #include <linux/miscdevice.h>
 #include <linux/fs.h>
 #include "lg.h"
 
+/*L:030 setup_regs() doesn't really belong in this file, but it gives us an
+ * early glimpse deeper into the Host so it's worth having here.
+ *
+ * Most of the Guest's registers are left alone: we used get_zeroed_page() to
+ * allocate the structure, so they will be 0. */
 static void setup_regs(struct lguest_regs *regs, unsigned long start)
 {
-        /* Write out stack in format lguest expects, so we can switch to it. */
+        /* There are four "segment" registers which the Guest needs to boot:
+         * The "code segment" register (cs) refers to the kernel code segment
+         * __KERNEL_CS, and the "data", "extra" and "stack" segment registers
+         * refer to the kernel data segment __KERNEL_DS.
+         *
+         * The privilege level is packed into the lower bits.  The Guest runs
+         * at privilege level 1 (GUEST_PL).*/
         regs->ds = regs->es = regs->ss = __KERNEL_DS|GUEST_PL;
         regs->cs = __KERNEL_CS|GUEST_PL;
-        regs->eflags = 0x202;   /* Interrupts enabled. */
+
+        /* The "eflags" register contains miscellaneous flags.  Bit 1 (0x002)
+         * is supposed to always be "1".  Bit 9 (0x200) controls whether
+         * interrupts are enabled.  We always leave interrupts enabled while
+         * running the Guest. */
+        regs->eflags = 0x202;
+
+        /* The "Extended Instruction Pointer" register says where the Guest is
+         * running. */
         regs->eip = start;
-        /* esi points to our boot information (physical address 0) */
+
+        /* %esi points to our boot information, at physical address 0, so don't
+         * touch it. */
 }
 
-/* + addr */
+/*L:310 To send DMA into the Guest, the Launcher needs to be able to ask for a
+ * DMA buffer.  This is done by writing LHREQ_GETDMA and the key to
+ * /dev/lguest. */
 static long user_get_dma(struct lguest *lg, const u32 __user *input)
 {
         unsigned long key, udma, irq;
 
+        /* Fetch the key they wrote to us. */
         if (get_user(key, input) != 0)
                 return -EFAULT;
+        /* Look for a free Guest DMA buffer bound to that key. */
         udma = get_dma_buffer(lg, key, &irq);
         if (!udma)
                 return -ENOENT;
 
-        /* We put irq number in udma->used_len. */
+        /* We need to tell the Launcher what interrupt the Guest expects after
+         * the buffer is filled.  We stash it in udma->used_len. */
         lgwrite_u32(lg, udma + offsetof(struct lguest_dma, used_len), irq);
+
+        /* The (guest-physical) address of the DMA buffer is returned from
+         * the write(). */
         return udma;
 }
 
-/* To force the Guest to stop running and return to the Launcher, the
+/*L:315 To force the Guest to stop running and return to the Launcher, the
  * Waker sets writes LHREQ_BREAK and the value "1" to /dev/lguest.  The
  * Launcher then writes LHREQ_BREAK and "0" to release the Waker. */
 static int break_guest_out(struct lguest *lg, const u32 __user *input)
@@ -54,7 +88,8 @@ static int break_guest_out(struct lguest *lg, const u32 __user *input)
         }
 }
 
-/* + irq */
+/*L:050 Sending an interrupt is done by writing LHREQ_IRQ and an interrupt
+ * number to /dev/lguest. */
 static int user_send_irq(struct lguest *lg, const u32 __user *input)
 {
         u32 irq;
@@ -63,14 +98,19 @@ static int user_send_irq(struct lguest *lg, const u32 __user *input)
                 return -EFAULT;
         if (irq >= LGUEST_IRQS)
                 return -EINVAL;
+        /* Next time the Guest runs, the core code will see if it can deliver
+         * this interrupt. */
         set_bit(irq, lg->irqs_pending);
         return 0;
 }
 
+/*L:040 Once our Guest is initialized, the Launcher makes it run by reading
+ * from /dev/lguest. */
 static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
 {
         struct lguest *lg = file->private_data;
 
+        /* You must write LHREQ_INITIALIZE first! */
         if (!lg)
                 return -EINVAL;
 
@@ -78,27 +118,52 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
         if (current != lg->tsk)
                 return -EPERM;
 
+        /* If the guest is already dead, we indicate why */
         if (lg->dead) {
                 size_t len;
 
+                /* lg->dead either contains an error code, or a string. */
                 if (IS_ERR(lg->dead))
                         return PTR_ERR(lg->dead);
 
+                /* We can only return as much as the buffer they read with. */
                 len = min(size, strlen(lg->dead)+1);
                 if (copy_to_user(user, lg->dead, len) != 0)
                         return -EFAULT;
                 return len;
         }
 
+        /* If we returned from read() last time because the Guest sent DMA,
+         * clear the flag. */
         if (lg->dma_is_pending)
                 lg->dma_is_pending = 0;
 
+        /* Run the Guest until something interesting happens. */
         return run_guest(lg, (unsigned long __user *)user);
 }
 
-/* Take: pfnlimit, pgdir, start, pageoffset. */
+/*L:020 The initialization write supplies 4 32-bit values (in addition to the
+ * 32-bit LHREQ_INITIALIZE value).  These are:
+ *
+ * pfnlimit: The highest (Guest-physical) page number the Guest should be
+ * allowed to access.  The Launcher has to live in Guest memory, so it sets
+ * this to ensure the Guest can't reach it.
+ *
+ * pgdir: The (Guest-physical) address of the top of the initial Guest
+ * pagetables (which are set up by the Launcher).
+ *
+ * start: The first instruction to execute ("eip" in x86-speak).
+ *
+ * page_offset: The PAGE_OFFSET constant in the Guest kernel.  We should
+ * probably wean the code off this, but it's a very useful constant!  Any
+ * address above this is within the Guest kernel, and any kernel address can
+ * quickly converted from physical to virtual by adding PAGE_OFFSET.  It's
+ * 0xC0000000 (3G) by default, but it's configurable at kernel build time.
+ */
 static int initialize(struct file *file, const u32 __user *input)
 {
+        /* "struct lguest" contains everything we (the Host) know about a
+         * Guest. */
         struct lguest *lg;
         int err, i;
         u32 args[4];
@@ -106,7 +171,7 @@ static int initialize(struct file *file, const u32 __user *input)
         /* We grab the Big Lguest lock, which protects the global array
          * "lguests" and multiple simultaneous initializations. */
         mutex_lock(&lguest_lock);
-
+        /* You can't initialize twice!  Close the device and start again... */
         if (file->private_data) {
                 err = -EBUSY;
                 goto unlock;
@@ -117,37 +182,70 @@ static int initialize(struct file *file, const u32 __user *input)
                 goto unlock;
         }
 
+        /* Find an unused guest. */
         i = find_free_guest();
         if (i < 0) {
                 err = -ENOSPC;
                 goto unlock;
         }
+        /* OK, we have an index into the "lguest" array: "lg" is a convenient
+         * pointer. */
         lg = &lguests[i];
+
+        /* Populate the easy fields of our "struct lguest" */
         lg->guestid = i;
         lg->pfn_limit = args[0];
         lg->page_offset = args[3];
+
+        /* We need a complete page for the Guest registers: they are accessible
+         * to the Guest and we can only grant it access to whole pages. */
         lg->regs_page = get_zeroed_page(GFP_KERNEL);
         if (!lg->regs_page) {
                 err = -ENOMEM;
                 goto release_guest;
         }
+        /* We actually put the registers at the bottom of the page. */
         lg->regs = (void *)lg->regs_page + PAGE_SIZE - sizeof(*lg->regs);
 
+        /* Initialize the Guest's shadow page tables, using the toplevel
+         * address the Launcher gave us.  This allocates memory, so can
+         * fail. */
         err = init_guest_pagetable(lg, args[1]);
         if (err)
                 goto free_regs;
 
+        /* Now we initialize the Guest's registers, handing it the start
+         * address. */
         setup_regs(lg->regs, args[2]);
+
+        /* There are a couple of GDT entries the Guest expects when first
+         * booting. */
         setup_guest_gdt(lg);
+
+        /* The timer for lguest's clock needs initialization. */
         init_clockdev(lg);
+
+        /* We keep a pointer to the Launcher task (ie. current task) for when
+         * other Guests want to wake this one (inter-Guest I/O). */
         lg->tsk = current;
+        /* We need to keep a pointer to the Launcher's memory map, because if
+         * the Launcher dies we need to clean it up.  If we don't keep a
+         * reference, it is destroyed before close() is called. */
         lg->mm = get_task_mm(lg->tsk);
+
+        /* Initialize the queue for the waker to wait on */
         init_waitqueue_head(&lg->break_wq);
+
+        /* We remember which CPU's pages this Guest used last, for optimization
+         * when the same Guest runs on the same CPU twice. */
         lg->last_pages = NULL;
+
+        /* We keep our "struct lguest" in the file's private_data. */
         file->private_data = lg;
 
         mutex_unlock(&lguest_lock);
 
+        /* And because this is a write() call, we return the length used. */
         return sizeof(args);
 
 free_regs:
@@ -159,9 +257,15 @@ unlock:
         return err;
 }
 
+/*L:010 The first operation the Launcher does must be a write.  All writes
+ * start with a 32 bit number: for the first write this must be
+ * LHREQ_INITIALIZE to set up the Guest.  After that the Launcher can use
+ * writes of other values to get DMA buffers and send interrupts. */
 static ssize_t write(struct file *file, const char __user *input,
                      size_t size, loff_t *off)
 {
+        /* Once the guest is initialized, we hold the "struct lguest" in the
+         * file private data. */
         struct lguest *lg = file->private_data;
         u32 req;
 
@@ -169,8 +273,11 @@ static ssize_t write(struct file *file, const char __user *input,
                 return -EFAULT;
         input += sizeof(req);
 
+        /* If you haven't initialized, you must do that first. */
         if (req != LHREQ_INITIALIZE && !lg)
                 return -EINVAL;
+
+        /* Once the Guest is dead, all you can do is read() why it died. */
         if (lg && lg->dead)
                 return -ENOENT;
 
@@ -192,33 +299,72 @@ static ssize_t write(struct file *file, const char __user *input,
         }
 }
 
+/*L:060 The final piece of interface code is the close() routine.  It reverses
+ * everything done in initialize().  This is usually called because the
+ * Launcher exited.
+ *
+ * Note that the close routine returns 0 or a negative error number: it can't
+ * really fail, but it can whine.  I blame Sun for this wart, and K&R C for
+ * letting them do it. :*/
 static int close(struct inode *inode, struct file *file)
 {
         struct lguest *lg = file->private_data;
 
+        /* If we never successfully initialized, there's nothing to clean up */
         if (!lg)
                 return 0;
 
+        /* We need the big lock, to protect from inter-guest I/O and other
+         * Launchers initializing guests. */
         mutex_lock(&lguest_lock);
         /* Cancels the hrtimer set via LHCALL_SET_CLOCKEVENT. */
         hrtimer_cancel(&lg->hrt);
+        /* Free any DMA buffers the Guest had bound. */
         release_all_dma(lg);
+        /* Free up the shadow page tables for the Guest. */
         free_guest_pagetable(lg);
+        /* Now all the memory cleanups are done, it's safe to release the
+         * Launcher's memory management structure. */
         mmput(lg->mm);
+        /* If lg->dead doesn't contain an error code it will be NULL or a
+         * kmalloc()ed string, either of which is ok to hand to kfree(). */
         if (!IS_ERR(lg->dead))
                 kfree(lg->dead);
+        /* We can free up the register page we allocated. */
         free_page(lg->regs_page);
+        /* We clear the entire structure, which also marks it as free for the
+         * next user. */
         memset(lg, 0, sizeof(*lg));
+        /* Release lock and exit. */
         mutex_unlock(&lguest_lock);
+
         return 0;
 }
 
+/*L:000
+ * Welcome to our journey through the Launcher!
+ *
+ * The Launcher is the Host userspace program which sets up, runs and services
+ * the Guest.  In fact, many comments in the Drivers which refer to "the Host"
+ * doing things are inaccurate: the Launcher does all the device handling for
+ * the Guest.  The Guest can't tell what's done by the the Launcher and what by
+ * the Host.
+ *
+ * Just to confuse you: to the Host kernel, the Launcher *is* the Guest and we
+ * shall see more of that later.
+ *
+ * We begin our understanding with the Host kernel interface which the Launcher
+ * uses: reading and writing a character device called /dev/lguest.  All the
+ * work happens in the read(), write() and close() routines: */
 static struct file_operations lguest_fops = {
         .owner   = THIS_MODULE,
         .release = close,
         .write   = write,
         .read    = read,
 };
+
+/* This is a textbook example of a "misc" character device.  Populate a "struct
+ * miscdevice" and register it with misc_register(). */
 static struct miscdevice lguest_dev = {
         .minor  = MISC_DYNAMIC_MINOR,
         .name   = "lguest",
diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c
index 1b0ba09b1269..b7a924ace684 100644
--- a/drivers/lguest/page_tables.c
+++ b/drivers/lguest/page_tables.c
@@ -1,5 +1,11 @@
-/* Shadow page table operations.
- * Copyright (C) Rusty Russell IBM Corporation 2006.
+/*P:700 The pagetable code, on the other hand, still shows the scars of
+ * previous encounters.  It's functional, and as neat as it can be in the
+ * circumstances, but be wary, for these things are subtle and break easily.
+ * The Guest provides a virtual to physical mapping, but we can neither trust
+ * it nor use it: we verify and convert it here to point the hardware to the
+ * actual Guest pages when running the Guest. :*/
+
+/* Copyright (C) Rusty Russell IBM Corporation 2006.
  * GPL v2 and any later version */
 #include <linux/mm.h>
 #include <linux/types.h>
@@ -9,38 +15,96 @@
 #include <asm/tlbflush.h>
 #include "lg.h"
 
+/*M:008 We hold reference to pages, which prevents them from being swapped.
+ * It'd be nice to have a callback in the "struct mm_struct" when Linux wants
+ * to swap out.  If we had this, and a shrinker callback to trim PTE pages, we
+ * could probably consider launching Guests as non-root. :*/
+
+/*H:300
+ * The Page Table Code
+ *
+ * We use two-level page tables for the Guest.  If you're not entirely
+ * comfortable with virtual addresses, physical addresses and page tables then
+ * I recommend you review lguest.c's "Page Table Handling" (with diagrams!).
+ *
+ * The Guest keeps page tables, but we maintain the actual ones here: these are
+ * called "shadow" page tables.  Which is a very Guest-centric name: these are
+ * the real page tables the CPU uses, although we keep them up to date to
+ * reflect the Guest's.  (See what I mean about weird naming?  Since when do
+ * shadows reflect anything?)
+ *
+ * Anyway, this is the most complicated part of the Host code.  There are seven
+ * parts to this:
+ *  (i) Setting up a page table entry for the Guest when it faults,
+ *  (ii) Setting up the page table entry for the Guest stack,
+ *  (iii) Setting up a page table entry when the Guest tells us it has changed,
+ *  (iv) Switching page tables,
+ *  (v) Flushing (thowing away) page tables,
+ *  (vi) Mapping the Switcher when the Guest is about to run,
+ *  (vii) Setting up the page tables initially.
+ :*/
+
+/* Pages a 4k long, and each page table entry is 4 bytes long, giving us 1024
+ * (or 2^10) entries per page. */
 #define PTES_PER_PAGE_SHIFT 10
 #define PTES_PER_PAGE (1 << PTES_PER_PAGE_SHIFT)
+
+/* 1024 entries in a page table page maps 1024 pages: 4MB.  The Switcher is
+ * conveniently placed at the top 4MB, so it uses a separate, complete PTE
+ * page.  */
 #define SWITCHER_PGD_INDEX (PTES_PER_PAGE - 1)
 
+/* We actually need a separate PTE page for each CPU.  Remember that after the
+ * Switcher code itself comes two pages for each CPU, and we don't want this
+ * CPU's guest to see the pages of any other CPU. */
 static DEFINE_PER_CPU(spte_t *, switcher_pte_pages);
 #define switcher_pte_page(cpu) per_cpu(switcher_pte_pages, cpu)
 
+/*H:320 With our shadow and Guest types established, we need to deal with
+ * them: the page table code is curly enough to need helper functions to keep
+ * it clear and clean.
+ *
+ * The first helper takes a virtual address, and says which entry in the top
+ * level page table deals with that address.  Since each top level entry deals
+ * with 4M, this effectively divides by 4M. */
 static unsigned vaddr_to_pgd_index(unsigned long vaddr)
 {
         return vaddr >> (PAGE_SHIFT + PTES_PER_PAGE_SHIFT);
 }
 
-/* These access the shadow versions (ie. the ones used by the CPU). */
+/* There are two functions which return pointers to the shadow (aka "real")
+ * page tables.
+ *
+ * spgd_addr() takes the virtual address and returns a pointer to the top-level
+ * page directory entry for that address.  Since we keep track of several page
+ * tables, the "i" argument tells us which one we're interested in (it's
+ * usually the current one). */
 static spgd_t *spgd_addr(struct lguest *lg, u32 i, unsigned long vaddr)
 {
         unsigned int index = vaddr_to_pgd_index(vaddr);
 
+        /* We kill any Guest trying to touch the Switcher addresses. */
         if (index >= SWITCHER_PGD_INDEX) {
                 kill_guest(lg, "attempt to access switcher pages");
                 index = 0;
         }
+        /* Return a pointer index'th pgd entry for the i'th page table. */
         return &lg->pgdirs[i].pgdir[index];
 }
 
+/* This routine then takes the PGD entry given above, which contains the
+ * address of the PTE page.  It then returns a pointer to the PTE entry for the
+ * given address. */
 static spte_t *spte_addr(struct lguest *lg, spgd_t spgd, unsigned long vaddr)
 {
         spte_t *page = __va(spgd.pfn << PAGE_SHIFT);
+        /* You should never call this if the PGD entry wasn't valid */
         BUG_ON(!(spgd.flags & _PAGE_PRESENT));
         return &page[(vaddr >> PAGE_SHIFT) % PTES_PER_PAGE];
 }
 
-/* These access the guest versions. */
+/* These two functions just like the above two, except they access the Guest
+ * page tables.  Hence they return a Guest address. */
 static unsigned long gpgd_addr(struct lguest *lg, unsigned long vaddr)
 {
         unsigned int index = vaddr >> (PAGE_SHIFT + PTES_PER_PAGE_SHIFT);
@@ -55,12 +119,24 @@ static unsigned long gpte_addr(struct lguest *lg,
         return gpage + ((vaddr>>PAGE_SHIFT) % PTES_PER_PAGE) * sizeof(gpte_t);
 }
 
-/* Do a virtual -> physical mapping on a user page. */
+/*H:350 This routine takes a page number given by the Guest and converts it to
+ * an actual, physical page number.  It can fail for several reasons: the
+ * virtual address might not be mapped by the Launcher, the write flag is set
+ * and the page is read-only, or the write flag was set and the page was
+ * shared so had to be copied, but we ran out of memory.
+ *
+ * This holds a reference to the page, so release_pte() is careful to
+ * put that back. */
 static unsigned long get_pfn(unsigned long virtpfn, int write)
 {
         struct page *page;
+        /* This value indicates failure. */
         unsigned long ret = -1UL;
 
+        /* get_user_pages() is a complex interface: it gets the "struct
+         * vm_area_struct" and "struct page" assocated with a range of pages.
+         * It also needs the task's mmap_sem held, and is not very quick.
+         * It returns the number of pages it got. */
         down_read(&current->mm->mmap_sem);
         if (get_user_pages(current, current->mm, virtpfn << PAGE_SHIFT,
                            1, write, 1, &page, NULL) == 1)
@@ -69,28 +145,47 @@ static unsigned long get_pfn(unsigned long virtpfn, int write)
         return ret;
 }
 
+/*H:340 Converting a Guest page table entry to a shadow (ie. real) page table
+ * entry can be a little tricky.  The flags are (almost) the same, but the
+ * Guest PTE contains a virtual page number: the CPU needs the real page
+ * number. */
 static spte_t gpte_to_spte(struct lguest *lg, gpte_t gpte, int write)
 {
         spte_t spte;
         unsigned long pfn;
 
-        /* We ignore the global flag. */
+        /* The Guest sets the global flag, because it thinks that it is using
+         * PGE.  We only told it to use PGE so it would tell us whether it was
+         * flushing a kernel mapping or a userspace mapping.  We don't actually
+         * use the global bit, so throw it away. */
         spte.flags = (gpte.flags & ~_PAGE_GLOBAL);
+
+        /* We need a temporary "unsigned long" variable to hold the answer from
+         * get_pfn(), because it returns 0xFFFFFFFF on failure, which wouldn't
+         * fit in spte.pfn.  get_pfn() finds the real physical number of the
+         * page, given the virtual number. */
         pfn = get_pfn(gpte.pfn, write);
         if (pfn == -1UL) {
                 kill_guest(lg, "failed to get page %u", gpte.pfn);
-                /* Must not put_page() bogus page on cleanup. */
+                /* When we destroy the Guest, we'll go through the shadow page
+                 * tables and release_pte() them.  Make sure we don't think
+                 * this one is valid! */
                 spte.flags = 0;
         }
+        /* Now we assign the page number, and our shadow PTE is complete. */
         spte.pfn = pfn;
         return spte;
 }
 
+/*H:460 And to complete the chain, release_pte() looks like this: */
 static void release_pte(spte_t pte)
 {
+        /* Remember that get_user_pages() took a reference to the page, in
+         * get_pfn()?  We have to put it back now. */
         if (pte.flags & _PAGE_PRESENT)
                 put_page(pfn_to_page(pte.pfn));
 }
+/*:*/
 
 static void check_gpte(struct lguest *lg, gpte_t gpte)
 {
@@ -104,11 +199,16 @@ static void check_gpgd(struct lguest *lg, gpgd_t gpgd)
                 kill_guest(lg, "bad page directory entry");
 }
 
-/* FIXME: We hold reference to pages, which prevents them from being
-   swapped.  It'd be nice to have a callback when Linux wants to swap out. */
-
-/* We fault pages in, which allows us to update accessed/dirty bits.
- * Return true if we got page. */
+/*H:330
+ * (i) Setting up a page table entry for the Guest when it faults
+ *
+ * We saw this call in run_guest(): when we see a page fault in the Guest, we
+ * come here.  That's because we only set up the shadow page tables lazily as
+ * they're needed, so we get page faults all the time and quietly fix them up
+ * and return to the Guest without it knowing.
+ *
+ * If we fixed up the fault (ie. we mapped the address), this routine returns
+ * true. */
 int demand_page(struct lguest *lg, unsigned long vaddr, int errcode)
 {
         gpgd_t gpgd;
@@ -117,106 +217,161 @@ int demand_page(struct lguest *lg, unsigned long vaddr, int errcode)
         gpte_t gpte;
         spte_t *spte;
 
+        /* First step: get the top-level Guest page table entry. */
         gpgd = mkgpgd(lgread_u32(lg, gpgd_addr(lg, vaddr)));
+        /* Toplevel not present?  We can't map it in. */
         if (!(gpgd.flags & _PAGE_PRESENT))
                 return 0;
 
+        /* Now look at the matching shadow entry. */
         spgd = spgd_addr(lg, lg->pgdidx, vaddr);
         if (!(spgd->flags & _PAGE_PRESENT)) {
-                /* Get a page of PTEs for them. */
+                /* No shadow entry: allocate a new shadow PTE page. */
                 unsigned long ptepage = get_zeroed_page(GFP_KERNEL);
-                /* FIXME: Steal from self in this case? */
+                /* This is not really the Guest's fault, but killing it is
+                 * simple for this corner case. */
                 if (!ptepage) {
                         kill_guest(lg, "out of memory allocating pte page");
                         return 0;
                 }
+                /* We check that the Guest pgd is OK. */
                 check_gpgd(lg, gpgd);
+                /* And we copy the flags to the shadow PGD entry.  The page
+                 * number in the shadow PGD is the page we just allocated. */
                 spgd->raw.val = (__pa(ptepage) | gpgd.flags);
         }
 
+        /* OK, now we look at the lower level in the Guest page table: keep its
+         * address, because we might update it later. */
         gpte_ptr = gpte_addr(lg, gpgd, vaddr);
         gpte = mkgpte(lgread_u32(lg, gpte_ptr));
 
-        /* No page? */
+        /* If this page isn't in the Guest page tables, we can't page it in. */
         if (!(gpte.flags & _PAGE_PRESENT))
                 return 0;
 
-        /* Write to read-only page? */
+        /* Check they're not trying to write to a page the Guest wants
+         * read-only (bit 2 of errcode == write). */
         if ((errcode & 2) && !(gpte.flags & _PAGE_RW))
                 return 0;
 
-        /* User access to a non-user page? */
+        /* User access to a kernel page? (bit 3 == user access) */
         if ((errcode & 4) && !(gpte.flags & _PAGE_USER))
                 return 0;
 
+        /* Check that the Guest PTE flags are OK, and the page number is below
+         * the pfn_limit (ie. not mapping the Launcher binary). */
         check_gpte(lg, gpte);
+        /* Add the _PAGE_ACCESSED and (for a write) _PAGE_DIRTY flag */
         gpte.flags |= _PAGE_ACCESSED;
         if (errcode & 2)
                 gpte.flags |= _PAGE_DIRTY;
 
-        /* We're done with the old pte. */
+        /* Get the pointer to the shadow PTE entry we're going to set. */
         spte = spte_addr(lg, *spgd, vaddr);
+        /* If there was a valid shadow PTE entry here before, we release it.
+         * This can happen with a write to a previously read-only entry. */
         release_pte(*spte);
 
-        /* We don't make it writable if this isn't a write: later
-         * write will fault so we can set dirty bit in guest. */
+        /* If this is a write, we insist that the Guest page is writable (the
+         * final arg to gpte_to_spte()). */
         if (gpte.flags & _PAGE_DIRTY)
                 *spte = gpte_to_spte(lg, gpte, 1);
         else {
+                /* If this is a read, don't set the "writable" bit in the page
+                 * table entry, even if the Guest says it's writable.  That way
+                 * we come back here when a write does actually ocur, so we can
+                 * update the Guest's _PAGE_DIRTY flag. */
                 gpte_t ro_gpte = gpte;
                 ro_gpte.flags &= ~_PAGE_RW;
                 *spte = gpte_to_spte(lg, ro_gpte, 0);
         }
 
-        /* Now we update dirty/accessed on guest. */
+        /* Finally, we write the Guest PTE entry back: we've set the
+         * _PAGE_ACCESSED and maybe the _PAGE_DIRTY flags. */
         lgwrite_u32(lg, gpte_ptr, gpte.raw.val);
+
+        /* We succeeded in mapping the page! */
         return 1;
 }
 
-/* This is much faster than the full demand_page logic. */
+/*H:360 (ii) Setting up the page table entry for the Guest stack.
+ *
+ * Remember pin_stack_pages() which makes sure the stack is mapped?  It could
+ * simply call demand_page(), but as we've seen that logic is quite long, and
+ * usually the stack pages are already mapped anyway, so it's not required.
+ *
+ * This is a quick version which answers the question: is this virtual address
+ * mapped by the shadow page tables, and is it writable? */
 static int page_writable(struct lguest *lg, unsigned long vaddr)
 {
         spgd_t *spgd;
         unsigned long flags;
 
+        /* Look at the top level entry: is it present? */
         spgd = spgd_addr(lg, lg->pgdidx, vaddr);
         if (!(spgd->flags & _PAGE_PRESENT))
                 return 0;
 
+        /* Check the flags on the pte entry itself: it must be present and
+         * writable. */
         flags = spte_addr(lg, *spgd, vaddr)->flags;
         return (flags & (_PAGE_PRESENT|_PAGE_RW)) == (_PAGE_PRESENT|_PAGE_RW);
 }
 
+/* So, when pin_stack_pages() asks us to pin a page, we check if it's already
+ * in the page tables, and if not, we call demand_page() with error code 2
+ * (meaning "write"). */
 void pin_page(struct lguest *lg, unsigned long vaddr)
 {
         if (!page_writable(lg, vaddr) && !demand_page(lg, vaddr, 2))
                 kill_guest(lg, "bad stack page %#lx", vaddr);
 }
 
+/*H:450 If we chase down the release_pgd() code, it looks like this: */
 static void release_pgd(struct lguest *lg, spgd_t *spgd)
 {
+        /* If the entry's not present, there's nothing to release. */
         if (spgd->flags & _PAGE_PRESENT) {
                 unsigned int i;
+                /* Converting the pfn to find the actual PTE page is easy: turn
+                 * the page number into a physical address, then convert to a
+                 * virtual address (easy for kernel pages like this one). */
                 spte_t *ptepage = __va(spgd->pfn << PAGE_SHIFT);
+                /* For each entry in the page, we might need to release it. */
                 for (i = 0; i < PTES_PER_PAGE; i++)
                         release_pte(ptepage[i]);
+                /* Now we can free the page of PTEs */
                 free_page((long)ptepage);
+                /* And zero out the PGD entry we we never release it twice. */
                 spgd->raw.val = 0;
         }
 }
 
+/*H:440 (v) Flushing (thowing away) page tables,
+ *
+ * We saw flush_user_mappings() called when we re-used a top-level pgdir page.
+ * It simply releases every PTE page from 0 up to the kernel address. */
 static void flush_user_mappings(struct lguest *lg, int idx)
 {
         unsigned int i;
+        /* Release every pgd entry up to the kernel's address. */
         for (i = 0; i < vaddr_to_pgd_index(lg->page_offset); i++)
                 release_pgd(lg, lg->pgdirs[idx].pgdir + i);
 }
 
+/* The Guest also has a hypercall to do this manually: it's used when a large
+ * number of mappings have been changed. */
 void guest_pagetable_flush_user(struct lguest *lg)
 {
+        /* Drop the userspace part of the current page table. */
         flush_user_mappings(lg, lg->pgdidx);
 }
+/*:*/
 
+/* We keep several page tables.  This is a simple routine to find the page
+ * table (if any) corresponding to this top-level address the Guest has given
+ * us. */
 static unsigned int find_pgdir(struct lguest *lg, unsigned long pgtable)
 {
         unsigned int i;
@@ -226,21 +381,30 @@ static unsigned int find_pgdir(struct lguest *lg, unsigned long pgtable)
         return i;
 }
 
+/*H:435 And this is us, creating the new page directory.  If we really do
+ * allocate a new one (and so the kernel parts are not there), we set
+ * blank_pgdir. */
 static unsigned int new_pgdir(struct lguest *lg,
                               unsigned long cr3,
                               int *blank_pgdir)
 {
         unsigned int next;
 
+        /* We pick one entry at random to throw out.  Choosing the Least
+         * Recently Used might be better, but this is easy. */
         next = random32() % ARRAY_SIZE(lg->pgdirs);
+        /* If it's never been allocated at all before, try now. */
         if (!lg->pgdirs[next].pgdir) {
                 lg->pgdirs[next].pgdir = (spgd_t *)get_zeroed_page(GFP_KERNEL);
+                /* If the allocation fails, just keep using the one we have */
                 if (!lg->pgdirs[next].pgdir)
                         next = lg->pgdidx;
                 else
-                        /* There are no mappings: you'll need to re-pin */
+                        /* This is a blank page, so there are no kernel
+                         * mappings: caller must map the stack! */
                         *blank_pgdir = 1;
         }
+        /* Record which Guest toplevel this shadows. */
         lg->pgdirs[next].cr3 = cr3;
         /* Release all the non-kernel mappings. */
         flush_user_mappings(lg, next);
@@ -248,82 +412,161 @@ static unsigned int new_pgdir(struct lguest *lg,
         return next;
 }
 
+/*H:430 (iv) Switching page tables
+ *
+ * This is what happens when the Guest changes page tables (ie. changes the
+ * top-level pgdir).  This happens on almost every context switch. */
 void guest_new_pagetable(struct lguest *lg, unsigned long pgtable)
 {
         int newpgdir, repin = 0;
 
+        /* Look to see if we have this one already. */
         newpgdir = find_pgdir(lg, pgtable);
+        /* If not, we allocate or mug an existing one: if it's a fresh one,
+         * repin gets set to 1. */
         if (newpgdir == ARRAY_SIZE(lg->pgdirs))
                 newpgdir = new_pgdir(lg, pgtable, &repin);
+        /* Change the current pgd index to the new one. */
         lg->pgdidx = newpgdir;
+        /* If it was completely blank, we map in the Guest kernel stack */
         if (repin)
                 pin_stack_pages(lg);
 }
 
+/*H:470 Finally, a routine which throws away everything: all PGD entries in all
+ * the shadow page tables.  This is used when we destroy the Guest. */
 static void release_all_pagetables(struct lguest *lg)
 {
         unsigned int i, j;
 
+        /* Every shadow pagetable this Guest has */
         for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++)
                 if (lg->pgdirs[i].pgdir)
+                        /* Every PGD entry except the Switcher at the top */
                         for (j = 0; j < SWITCHER_PGD_INDEX; j++)
                                 release_pgd(lg, lg->pgdirs[i].pgdir + j);
 }
 
+/* We also throw away everything when a Guest tells us it's changed a kernel
+ * mapping.  Since kernel mappings are in every page table, it's easiest to
+ * throw them all away.  This is amazingly slow, but thankfully rare. */
 void guest_pagetable_clear_all(struct lguest *lg)
 {
         release_all_pagetables(lg);
+        /* We need the Guest kernel stack mapped again. */
         pin_stack_pages(lg);
 }
 
+/*H:420 This is the routine which actually sets the page table entry for then
+ * "idx"'th shadow page table.
+ *
+ * Normally, we can just throw out the old entry and replace it with 0: if they
+ * use it demand_page() will put the new entry in.  We need to do this anyway:
+ * The Guest expects _PAGE_ACCESSED to be set on its PTE the first time a page
+ * is read from, and _PAGE_DIRTY when it's written to.
+ *
+ * But Avi Kivity pointed out that most Operating Systems (Linux included) set
+ * these bits on PTEs immediately anyway.  This is done to save the CPU from
+ * having to update them, but it helps us the same way: if they set
+ * _PAGE_ACCESSED then we can put a read-only PTE entry in immediately, and if
+ * they set _PAGE_DIRTY then we can put a writable PTE entry in immediately.
+ */
 static void do_set_pte(struct lguest *lg, int idx,
                        unsigned long vaddr, gpte_t gpte)
 {
+        /* Look up the matching shadow page directot entry. */
         spgd_t *spgd = spgd_addr(lg, idx, vaddr);
+
+        /* If the top level isn't present, there's no entry to update. */
         if (spgd->flags & _PAGE_PRESENT) {
+                /* Otherwise, we start by releasing the existing entry. */
                 spte_t *spte = spte_addr(lg, *spgd, vaddr);
                 release_pte(*spte);
+
+                /* If they're setting this entry as dirty or accessed, we might
+                 * as well put that entry they've given us in now.  This shaves
+                 * 10% off a copy-on-write micro-benchmark. */
                 if (gpte.flags & (_PAGE_DIRTY | _PAGE_ACCESSED)) {
                         check_gpte(lg, gpte);
                         *spte = gpte_to_spte(lg, gpte, gpte.flags&_PAGE_DIRTY);
                 } else
+                        /* Otherwise we can demand_page() it in later. */
                         spte->raw.val = 0;
         }
 }
 
+/*H:410 Updating a PTE entry is a little trickier.
+ *
+ * We keep track of several different page tables (the Guest uses one for each
+ * process, so it makes sense to cache at least a few).  Each of these have
+ * identical kernel parts: ie. every mapping above PAGE_OFFSET is the same for
+ * all processes.  So when the page table above that address changes, we update
+ * all the page tables, not just the current one.  This is rare.
+ *
+ * The benefit is that when we have to track a new page table, we can copy keep
+ * all the kernel mappings.  This speeds up context switch immensely. */
 void guest_set_pte(struct lguest *lg,
                    unsigned long cr3, unsigned long vaddr, gpte_t gpte)
 {
-        /* Kernel mappings must be changed on all top levels. */
+        /* Kernel mappings must be changed on all top levels.  Slow, but
+         * doesn't happen often. */
         if (vaddr >= lg->page_offset) {
                 unsigned int i;
                 for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++)
                         if (lg->pgdirs[i].pgdir)
                                 do_set_pte(lg, i, vaddr, gpte);
         } else {
+                /* Is this page table one we have a shadow for? */
                 int pgdir = find_pgdir(lg, cr3);
                 if (pgdir != ARRAY_SIZE(lg->pgdirs))
+                        /* If so, do the update. */
                         do_set_pte(lg, pgdir, vaddr, gpte);
         }
 }
 
+/*H:400
+ * (iii) Setting up a page table entry when the Guest tells us it has changed.
+ *
+ * Just like we did in interrupts_and_traps.c, it makes sense for us to deal
+ * with the other side of page tables while we're here: what happens when the
+ * Guest asks for a page table to be updated?
+ *
+ * We already saw that demand_page() will fill in the shadow page tables when
+ * needed, so we can simply remove shadow page table entries whenever the Guest
+ * tells us they've changed.  When the Guest tries to use the new entry it will
+ * fault and demand_page() will fix it up.
+ *
+ * So with that in mind here's our code to to update a (top-level) PGD entry:
+ */
 void guest_set_pmd(struct lguest *lg, unsigned long cr3, u32 idx)
 {
         int pgdir;
 
+        /* The kernel seems to try to initialize this early on: we ignore its
+         * attempts to map over the Switcher. */
         if (idx >= SWITCHER_PGD_INDEX)
                 return;
 
+        /* If they're talking about a page table we have a shadow for... */
         pgdir = find_pgdir(lg, cr3);
         if (pgdir < ARRAY_SIZE(lg->pgdirs))
+                /* ... throw it away. */
                 release_pgd(lg, lg->pgdirs[pgdir].pgdir + idx);
 }
 
+/*H:500 (vii) Setting up the page tables initially.
+ *
+ * When a Guest is first created, the Launcher tells us where the toplevel of
+ * its first page table is.  We set some things up here: */
 int init_guest_pagetable(struct lguest *lg, unsigned long pgtable)
 {
-        /* We assume this in flush_user_mappings, so check now */
+        /* In flush_user_mappings() we loop from 0 to
+         * "vaddr_to_pgd_index(lg->page_offset)".  This assumes it won't hit
+         * the Switcher mappings, so check that now. */
         if (vaddr_to_pgd_index(lg->page_offset) >= SWITCHER_PGD_INDEX)
                 return -EINVAL;
+        /* We start on the first shadow page table, and give it a blank PGD
+         * page. */
         lg->pgdidx = 0;
         lg->pgdirs[lg->pgdidx].cr3 = pgtable;
         lg->pgdirs[lg->pgdidx].pgdir = (spgd_t*)get_zeroed_page(GFP_KERNEL);
@@ -332,33 +575,48 @@ int init_guest_pagetable(struct lguest *lg, unsigned long pgtable)
         return 0;
 }
 
+/* When a Guest dies, our cleanup is fairly simple. */
 void free_guest_pagetable(struct lguest *lg)
 {
         unsigned int i;
 
+        /* Throw away all page table pages. */
         release_all_pagetables(lg);
+        /* Now free the top levels: free_page() can handle 0 just fine. */
         for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++)
                 free_page((long)lg->pgdirs[i].pgdir);
 }
 
-/* Caller must be preempt-safe */
+/*H:480 (vi) Mapping the Switcher when the Guest is about to run.
+ *
+ * The Switcher and the two pages for this CPU need to be available to the
+ * Guest (and not the pages for other CPUs).  We have the appropriate PTE pages
+ * for each CPU already set up, we just need to hook them in. */
 void map_switcher_in_guest(struct lguest *lg, struct lguest_pages *pages)
 {
         spte_t *switcher_pte_page = __get_cpu_var(switcher_pte_pages);
         spgd_t switcher_pgd;
         spte_t regs_pte;
 
-        /* Since switcher less that 4MB, we simply mug top pte page. */
+        /* Make the last PGD entry for this Guest point to the Switcher's PTE
+         * page for this CPU (with appropriate flags). */
         switcher_pgd.pfn = __pa(switcher_pte_page) >> PAGE_SHIFT;
         switcher_pgd.flags = _PAGE_KERNEL;
         lg->pgdirs[lg->pgdidx].pgdir[SWITCHER_PGD_INDEX] = switcher_pgd;
 
-        /* Map our regs page over stack page. */
+        /* We also change the Switcher PTE page.  When we're running the Guest,
+         * we want the Guest's "regs" page to appear where the first Switcher
+         * page for this CPU is.  This is an optimization: when the Switcher
+         * saves the Guest registers, it saves them into the first page of this
+         * CPU's "struct lguest_pages": if we make sure the Guest's register
+         * page is already mapped there, we don't have to copy them out
+         * again. */
         regs_pte.pfn = __pa(lg->regs_page) >> PAGE_SHIFT;
         regs_pte.flags = _PAGE_KERNEL;
         switcher_pte_page[(unsigned long)pages/PAGE_SIZE%PTES_PER_PAGE]
                 = regs_pte;
 }
+/*:*/
 
 static void free_switcher_pte_pages(void)
 {
@@ -368,6 +626,10 @@ static void free_switcher_pte_pages(void)
                 free_page((long)switcher_pte_page(i));
 }
 
+/*H:520 Setting up the Switcher PTE page for given CPU is fairly easy, given
+ * the CPU number and the "struct page"s for the Switcher code itself.
+ *
+ * Currently the Switcher is less than a page long, so "pages" is always 1. */
 static __init void populate_switcher_pte_page(unsigned int cpu,
                                               struct page *switcher_page[],
                                               unsigned int pages)
@@ -375,21 +637,26 @@ static __init void populate_switcher_pte_page(unsigned int cpu,
         unsigned int i;
         spte_t *pte = switcher_pte_page(cpu);
 
+        /* The first entries are easy: they map the Switcher code. */
         for (i = 0; i < pages; i++) {
                 pte[i].pfn = page_to_pfn(switcher_page[i]);
                 pte[i].flags = _PAGE_PRESENT|_PAGE_ACCESSED;
         }
 
-        /* We only map this CPU's pages, so guest can't see others. */
+        /* The only other thing we map is this CPU's pair of pages. */
         i = pages + cpu*2;
 
-        /* First page (regs) is rw, second (state) is ro. */
+        /* First page (Guest registers) is writable from the Guest */
         pte[i].pfn = page_to_pfn(switcher_page[i]);
         pte[i].flags = _PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_RW;
+        /* The second page contains the "struct lguest_ro_state", and is
+         * read-only. */
         pte[i+1].pfn = page_to_pfn(switcher_page[i+1]);
         pte[i+1].flags = _PAGE_PRESENT|_PAGE_ACCESSED;
 }
 
+/*H:510 At boot or module load time, init_pagetables() allocates and populates
+ * the Switcher PTE page for each CPU. */
 __init int init_pagetables(struct page **switcher_page, unsigned int pages)
 {
         unsigned int i;
@@ -404,7 +671,9 @@ __init int init_pagetables(struct page **switcher_page, unsigned int pages)
         }
         return 0;
 }
+/*:*/
 
+/* Cleaning up simply involves freeing the PTE page for each CPU. */
 void free_pagetables(void)
 {
         free_switcher_pte_pages();
diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c
index 1b2cfe89dcd5..f675a41a80da 100644
--- a/drivers/lguest/segments.c
+++ b/drivers/lguest/segments.c
@@ -1,16 +1,68 @@
+/*P:600 The x86 architecture has segments, which involve a table of descriptors
+ * which can be used to do funky things with virtual address interpretation.
+ * We originally used to use segments so the Guest couldn't alter the
+ * Guest<->Host Switcher, and then we had to trim Guest segments, and restore
+ * for userspace per-thread segments, but trim again for on userspace->kernel
+ * transitions...  This nightmarish creation was contained within this file,
+ * where we knew not to tread without heavy armament and a change of underwear.
+ *
+ * In these modern times, the segment handling code consists of simple sanity
+ * checks, and the worst you'll experience reading this code is butterfly-rash
+ * from frolicking through its parklike serenity. :*/
 #include "lg.h"
 
+/*H:600
+ * We've almost completed the Host; there's just one file to go!
+ *
+ * Segments & The Global Descriptor Table
+ *
+ * (That title sounds like a bad Nerdcore group.  Not to suggest that there are
+ * any good Nerdcore groups, but in high school a friend of mine had a band
+ * called Joe Fish and the Chips, so there are definitely worse band names).
+ *
+ * To refresh: the GDT is a table of 8-byte values describing segments.  Once
+ * set up, these segments can be loaded into one of the 6 "segment registers".
+ *
+ * GDT entries are passed around as "struct desc_struct"s, which like IDT
+ * entries are split into two 32-bit members, "a" and "b".  One day, someone
+ * will clean that up, and be declared a Hero.  (No pressure, I'm just saying).
+ *
+ * Anyway, the GDT entry contains a base (the start address of the segment), a
+ * limit (the size of the segment - 1), and some flags.  Sounds simple, and it
+ * would be, except those zany Intel engineers decided that it was too boring
+ * to put the base at one end, the limit at the other, and the flags in
+ * between.  They decided to shotgun the bits at random throughout the 8 bytes,
+ * like so:
+ *
+ * 0               16                     40       48  52  56     63
+ * [ limit part 1 ][     base part 1     ][ flags ][li][fl][base ]
+ *                                                  mit ags part 2
+ *                                                part 2
+ *
+ * As a result, this file contains a certain amount of magic numeracy.  Let's
+ * begin.
+ */
+
+/* Is the descriptor the Guest wants us to put in OK?
+ *
+ * The flag which Intel says must be zero: must be zero.  The descriptor must
+ * be present, (this is actually checked earlier but is here for thorougness),
+ * and the descriptor type must be 1 (a memory segment).  */
 static int desc_ok(const struct desc_struct *gdt)
 {
-        /* MBZ=0, P=1, DT=1  */
         return ((gdt->b & 0x00209000) == 0x00009000);
 }
 
+/* Is the segment present?  (Otherwise it can't be used by the Guest). */
 static int segment_present(const struct desc_struct *gdt)
 {
         return gdt->b & 0x8000;
 }
 
+/* There are several entries we don't let the Guest set.  The TSS entry is the
+ * "Task State Segment" which controls all kinds of delicate things.  The
+ * LGUEST_CS and LGUEST_DS entries are reserved for the Switcher, and the
+ * the Guest can't be trusted to deal with double faults. */
 static int ignored_gdt(unsigned int num)
 {
         return (num == GDT_ENTRY_TSS
@@ -19,9 +71,18 @@ static int ignored_gdt(unsigned int num)
                 || num == GDT_ENTRY_DOUBLEFAULT_TSS);
 }
 
-/* We don't allow removal of CS, DS or SS; it doesn't make sense. */
+/* If the Guest asks us to remove an entry from the GDT, we have to be careful.
+ * If one of the segment registers is pointing at that entry the Switcher will
+ * crash when it tries to reload the segment registers for the Guest.
+ *
+ * It doesn't make much sense for the Guest to try to remove its own code, data
+ * or stack segments while they're in use: assume that's a Guest bug.  If it's
+ * one of the lesser segment registers using the removed entry, we simply set
+ * that register to 0 (unusable). */
 static void check_segment_use(struct lguest *lg, unsigned int desc)
 {
+        /* GDT entries are 8 bytes long, so we divide to get the index and
+         * ignore the bottom bits. */
         if (lg->regs->gs / 8 == desc)
                 lg->regs->gs = 0;
         if (lg->regs->fs / 8 == desc)
@@ -33,13 +94,21 @@ static void check_segment_use(struct lguest *lg, unsigned int desc)
             || lg->regs->ss / 8 == desc)
                 kill_guest(lg, "Removed live GDT entry %u", desc);
 }
-
+/*:*/
+/*M:009 We wouldn't need to check for removal of in-use segments if we handled
+ * faults in the Switcher.  However, it's probably not a worthwhile
+ * optimization. :*/
+
+/*H:610 Once the GDT has been changed, we look through the changed entries and
+ * see if they're OK.  If not, we'll call kill_guest() and the Guest will never
+ * get to use the invalid entries. */
 static void fixup_gdt_table(struct lguest *lg, unsigned start, unsigned end)
 {
         unsigned int i;
 
         for (i = start; i < end; i++) {
-                /* We never copy these ones to real gdt */
+                /* We never copy these ones to real GDT, so we don't care what
+                 * they say */
                 if (ignored_gdt(i))
                         continue;
 
@@ -53,41 +122,57 @@ static void fixup_gdt_table(struct lguest *lg, unsigned start, unsigned end)
                 if (!desc_ok(&lg->gdt[i]))
                         kill_guest(lg, "Bad GDT descriptor %i", i);
 
-                /* DPL 0 presumably means "for use by guest". */
+                /* Segment descriptors contain a privilege level: the Guest is
+                 * sometimes careless and leaves this as 0, even though it's
+                 * running at privilege level 1.  If so, we fix it here. */
                 if ((lg->gdt[i].b & 0x00006000) == 0)
                         lg->gdt[i].b |= (GUEST_PL << 13);
 
-                /* Set accessed bit, since gdt isn't writable. */
+                /* Each descriptor has an "accessed" bit.  If we don't set it
+                 * now, the CPU will try to set it when the Guest first loads
+                 * that entry into a segment register.  But the GDT isn't
+                 * writable by the Guest, so bad things can happen. */
                 lg->gdt[i].b |= 0x00000100;
         }
 }
 
+/* This routine is called at boot or modprobe time for each CPU to set up the
+ * "constant" GDT entries for Guests running on that CPU. */
 void setup_default_gdt_entries(struct lguest_ro_state *state)
 {
         struct desc_struct *gdt = state->guest_gdt;
         unsigned long tss = (unsigned long)&state->guest_tss;
 
-        /* Hypervisor segments. */
+        /* The hypervisor segments are full 0-4G segments, privilege level 0 */
         gdt[GDT_ENTRY_LGUEST_CS] = FULL_EXEC_SEGMENT;
         gdt[GDT_ENTRY_LGUEST_DS] = FULL_SEGMENT;
 
-        /* This is the one which we *cannot* copy from guest, since tss
-           is depended on this lguest_ro_state, ie. this cpu. */
+        /* The TSS segment refers to the TSS entry for this CPU, so we cannot
+         * copy it from the Guest.  Forgive the magic flags */
         gdt[GDT_ENTRY_TSS].a = 0x00000067 | (tss << 16);
         gdt[GDT_ENTRY_TSS].b = 0x00008900 | (tss & 0xFF000000)
                 | ((tss >> 16) & 0x000000FF);
 }
 
+/* This routine is called before the Guest is run for the first time. */
 void setup_guest_gdt(struct lguest *lg)
 {
+        /* Start with full 0-4G segments... */
         lg->gdt[GDT_ENTRY_KERNEL_CS] = FULL_EXEC_SEGMENT;
         lg->gdt[GDT_ENTRY_KERNEL_DS] = FULL_SEGMENT;
+        /* ...except the Guest is allowed to use them, so set the privilege
+         * level appropriately in the flags. */
         lg->gdt[GDT_ENTRY_KERNEL_CS].b |= (GUEST_PL << 13);
         lg->gdt[GDT_ENTRY_KERNEL_DS].b |= (GUEST_PL << 13);
 }
 
-/* This is a fast version for the common case where only the three TLS entries
- * have changed. */
+/* Like the IDT, we never simply use the GDT the Guest gives us.  We set up the
+ * GDTs for each CPU, then we copy across the entries each time we want to run
+ * a different Guest on that CPU. */
+
+/* A partial GDT load, for the three "thead-local storage" entries.  Otherwise
+ * it's just like load_guest_gdt().  So much, in fact, it would probably be
+ * neater to have a single hypercall to cover both. */
 void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt)
 {
         unsigned int i;
@@ -96,22 +181,31 @@ void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt)
                 gdt[i] = lg->gdt[i];
 }
 
+/* This is the full version */
 void copy_gdt(const struct lguest *lg, struct desc_struct *gdt)
 {
         unsigned int i;
 
+        /* The default entries from setup_default_gdt_entries() are not
+         * replaced.  See ignored_gdt() above. */
         for (i = 0; i < GDT_ENTRIES; i++)
                 if (!ignored_gdt(i))
                         gdt[i] = lg->gdt[i];
 }
 
+/* This is where the Guest asks us to load a new GDT (LHCALL_LOAD_GDT). */
 void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num)
 {
+        /* We assume the Guest has the same number of GDT entries as the
+         * Host, otherwise we'd have to dynamically allocate the Guest GDT. */
         if (num > ARRAY_SIZE(lg->gdt))
                 kill_guest(lg, "too many gdt entries %i", num);
 
+        /* We read the whole thing in, then fix it up. */
         lgread(lg, lg->gdt, table, num * sizeof(lg->gdt[0]));
         fixup_gdt_table(lg, 0, ARRAY_SIZE(lg->gdt));
+        /* Mark that the GDT changed so the core knows it has to copy it again,
+         * even if the Guest is run on the same CPU. */
         lg->changed |= CHANGED_GDT;
 }
 
@@ -123,3 +217,13 @@ void guest_load_tls(struct lguest *lg, unsigned long gtls)
         fixup_gdt_table(lg, GDT_ENTRY_TLS_MIN, GDT_ENTRY_TLS_MAX+1);
         lg->changed |= CHANGED_GDT_TLS;
 }
+
+/*
+ * With this, we have finished the Host.
+ *
+ * Five of the seven parts of our task are complete.  You have made it through
+ * the Bit of Despair (I think that's somewhere in the page table code,
+ * myself).
+ *
+ * Next, we examine "make Switcher".  It's short, but intense.
+ */
diff --git a/drivers/lguest/switcher.S b/drivers/lguest/switcher.S
index eadd4cc299d2..d418179ea6b5 100644
--- a/drivers/lguest/switcher.S
+++ b/drivers/lguest/switcher.S
@@ -1,45 +1,136 @@
-/* This code sits at 0xFFC00000 to do the low-level guest<->host switch.
+/*P:900 This is the Switcher: code which sits at 0xFFC00000 to do the low-level
+ * Guest<->Host switch.  It is as simple as it can be made, but it's naturally
+ * very specific to x86.
+ *
+ * You have now completed Preparation.  If this has whet your appetite; if you
+ * are feeling invigorated and refreshed then the next, more challenging stage
+ * can be found in "make Guest". :*/
 
-   There is are two pages above us for this CPU (struct lguest_pages).
-   The second page (struct lguest_ro_state) becomes read-only after the
-   context switch.  The first page (the stack for traps) remains writable,
-   but while we're in here, the guest cannot be running.
-*/
+/*S:100
+ * Welcome to the Switcher itself!
+ *
+ * This file contains the low-level code which changes the CPU to run the Guest
+ * code, and returns to the Host when something happens.  Understand this, and
+ * you understand the heart of our journey.
+ *
+ * Because this is in assembler rather than C, our tale switches from prose to
+ * verse.  First I tried limericks:
+ *
+ *      There once was an eax reg,
+ *      To which our pointer was fed,
+ *      It needed an add,
+ *      Which asm-offsets.h had
+ *      But this limerick is hurting my head.
+ *
+ * Next I tried haikus, but fitting the required reference to the seasons in
+ * every stanza was quickly becoming tiresome:
+ *
+ *      The %eax reg
+ *      Holds "struct lguest_pages" now:
+ *      Cherry blossoms fall.
+ *
+ * Then I started with Heroic Verse, but the rhyming requirement leeched away
+ * the content density and led to some uniquely awful oblique rhymes:
+ *
+ *      These constants are coming from struct offsets
+ *      For use within the asm switcher text.
+ *
+ * Finally, I settled for something between heroic hexameter, and normal prose
+ * with inappropriate linebreaks.  Anyway, it aint no Shakespeare.
+ */
+
+// Not all kernel headers work from assembler
+// But these ones are needed: the ENTRY() define
+// And constants extracted from struct offsets
+// To avoid magic numbers and breakage:
+// Should they change the compiler can't save us
+// Down here in the depths of assembler code.
 #include <linux/linkage.h>
 #include <asm/asm-offsets.h>
 #include "lg.h"
 
+// We mark the start of the code to copy
+// It's placed in .text tho it's never run here
+// You'll see the trick macro at the end
+// Which interleaves data and text to effect.
 .text
 ENTRY(start_switcher_text)
 
-/* %eax points to lguest pages for this CPU.  %ebx contains cr3 value.
-   All normal registers can be clobbered! */
+// When we reach switch_to_guest we have just left
+// The safe and comforting shores of C code
+// %eax has the "struct lguest_pages" to use
+// Where we save state and still see it from the Guest
+// And %ebx holds the Guest shadow pagetable:
+// Once set we have truly left Host behind.
 ENTRY(switch_to_guest)
-        /* Save host segments on host stack. */
+        // We told gcc all its regs could fade,
+        // Clobbered by our journey into the Guest
+        // We could have saved them, if we tried
+        // But time is our master and cycles count.
+
+        // Segment registers must be saved for the Host
+        // We push them on the Host stack for later
         pushl   %es
         pushl   %ds
         pushl   %gs
         pushl   %fs
-        /* With CONFIG_FRAME_POINTER, gcc doesn't let us clobber this! */
+        // But the compiler is fickle, and heeds
+        // No warning of %ebp clobbers
+        // When frame pointers are used.  That register
+        // Must be saved and restored or chaos strikes.
         pushl   %ebp
-        /* Save host stack. */
+        // The Host's stack is done, now save it away
+        // In our "struct lguest_pages" at offset
+        // Distilled into asm-offsets.h
         movl    %esp, LGUEST_PAGES_host_sp(%eax)
-        /* Switch to guest stack: if we get NMI we expect to be there. */
+
+        // All saved and there's now five steps before us:
+        // Stack, GDT, IDT, TSS
+        // And last of all the page tables are flipped.
+
+        // Yet beware that our stack pointer must be
+        // Always valid lest an NMI hits
+        // %edx does the duty here as we juggle
+        // %eax is lguest_pages: our stack lies within.
         movl    %eax, %edx
         addl    $LGUEST_PAGES_regs, %edx
         movl    %edx, %esp
-        /* Switch to guest's GDT, IDT. */
+
+        // The Guest's GDT we so carefully
+        // Placed in the "struct lguest_pages" before
         lgdt    LGUEST_PAGES_guest_gdt_desc(%eax)
+
+        // The Guest's IDT we did partially
+        // Move to the "struct lguest_pages" as well.
         lidt    LGUEST_PAGES_guest_idt_desc(%eax)
-        /* Switch to guest's TSS while GDT still writable. */
+
+        // The TSS entry which controls traps
+        // Must be loaded up with "ltr" now:
+        // For after we switch over our page tables
+        // It (as the rest) will be writable no more.
+        // (The GDT entry TSS needs
+        // Changes type when we load it: damn Intel!)
         movl    $(GDT_ENTRY_TSS*8), %edx
         ltr     %dx
-        /* Set host's TSS GDT entry to available (clear byte 5 bit 2). */
+
+        // Look back now, before we take this last step!
+        // The Host's TSS entry was also marked used;
+        // Let's clear it again, ere we return.
+        // The GDT descriptor of the Host
+        // Points to the table after two "size" bytes
         movl    (LGUEST_PAGES_host_gdt_desc+2)(%eax), %edx
+        // Clear the type field of "used" (byte 5, bit 2)
         andb    $0xFD, (GDT_ENTRY_TSS*8 + 5)(%edx)
-        /* Switch to guest page tables: lguest_pages->state now read-only. */
+
+        // Once our page table's switched, the Guest is live!
+        // The Host fades as we run this final step.
+        // Our "struct lguest_pages" is now read-only.
         movl    %ebx, %cr3
-        /* Restore guest regs */
+
+        // The page table change did one tricky thing:
+        // The Guest's register page has been mapped
+        // Writable onto our %esp (stack) --
+        // We can simply pop off all Guest regs.
         popl    %ebx
         popl    %ecx
         popl    %edx
@@ -51,12 +142,27 @@ ENTRY(switch_to_guest)
         popl    %fs
         popl    %ds
         popl    %es
-        /* Skip error code and trap number */
+
+        // Near the base of the stack lurk two strange fields
+        // Which we fill as we exit the Guest
+        // These are the trap number and its error
+        // We can simply step past them on our way.
         addl    $8, %esp
+
+        // The last five stack slots hold return address
+        // And everything needed to change privilege
+        // Into the Guest privilege level of 1,
+        // And the stack where the Guest had last left it.
+        // Interrupts are turned back on: we are Guest.
         iret
 
+// There are two paths where we switch to the Host
+// So we put the routine in a macro.
+// We are on our way home, back to the Host
+// Interrupted out of the Guest, we come here.
 #define SWITCH_TO_HOST                                                  \
-        /* Save guest state */                                          \
+        /* We save the Guest state: all registers first                 \
+         * Laid out just as "struct lguest_regs" defines */             \
         pushl   %es;                                                    \
         pushl   %ds;                                                    \
         pushl   %fs;                                                    \
@@ -68,58 +174,119 @@ ENTRY(switch_to_guest)
         pushl   %edx;                                                   \
         pushl   %ecx;                                                   \
         pushl   %ebx;                                                   \
-        /* Load lguest ds segment for convenience. */                   \
+        /* Our stack and our code are using segments                    \
+         * Set in the TSS and IDT                                       \
+         * Yet if we were to touch data we'd use                        \
+         * Whatever data segment the Guest had.                         \
+         * Load the lguest ds segment for now. */                       \
         movl    $(LGUEST_DS), %eax;                                     \
         movl    %eax, %ds;                                              \
-        /* Figure out where we are, based on stack (at top of regs). */ \
+        /* So where are we?  Which CPU, which struct?                   \
+         * The stack is our clue: our TSS sets                          \
+         * It at the end of "struct lguest_pages"                       \
+         * And we then pushed and pushed and pushed Guest regs:         \
+         * Now stack points atop the "struct lguest_regs".              \
+         * Subtract that offset, and we find our struct. */             \
         movl    %esp, %eax;                                             \
         subl    $LGUEST_PAGES_regs, %eax;                               \
-        /* Put trap number in %ebx before we switch cr3 and lose it. */ \
+        /* Save our trap number: the switch will obscure it             \
+         * (The Guest regs are not mapped here in the Host)             \
+         * %ebx holds it safe for deliver_to_host */                    \
         movl    LGUEST_PAGES_regs_trapnum(%eax), %ebx;                  \
-        /* Switch to host page tables (host GDT, IDT and stack are in host   \
-           mem, so need this first) */                                  \
+        /* The Host GDT, IDT and stack!                                 \
+         * All these lie safely hidden from the Guest:                  \
+         * We must return to the Host page tables                       \
+         * (Hence that was saved in struct lguest_pages) */             \
         movl    LGUEST_PAGES_host_cr3(%eax), %edx;                      \
         movl    %edx, %cr3;                                             \
-        /* Set guest's TSS to available (clear byte 5 bit 2). */        \
+        /* As before, when we looked back at the Host                   \
+         * As we left and marked TSS unused                             \
+         * So must we now for the Guest left behind. */                 \
         andb    $0xFD, (LGUEST_PAGES_guest_gdt+GDT_ENTRY_TSS*8+5)(%eax); \
-        /* Switch to host's GDT & IDT. */                               \
+        /* Switch to Host's GDT, IDT. */                                \
         lgdt    LGUEST_PAGES_host_gdt_desc(%eax);                       \
         lidt    LGUEST_PAGES_host_idt_desc(%eax);                       \
-        /* Switch to host's stack. */                                   \
+        /* Restore the Host's stack where it's saved regs lie */        \
         movl    LGUEST_PAGES_host_sp(%eax), %esp;                       \
-        /* Switch to host's TSS */                                      \
+        /* Last the TSS: our Host is complete */                        \
         movl    $(GDT_ENTRY_TSS*8), %edx;                               \
         ltr     %dx;                                                    \
+        /* Restore now the regs saved right at the first. */            \
         popl    %ebp;                                                   \
         popl    %fs;                                                    \
         popl    %gs;                                                    \
         popl    %ds;                                                    \
         popl    %es
 
-/* Return to run_guest_once. */
+// Here's where we come when the Guest has just trapped:
+// (Which trap we'll see has been pushed on the stack).
+// We need only switch back, and the Host will decode
+// Why we came home, and what needs to be done.
 return_to_host:
         SWITCH_TO_HOST
         iret
 
+// An interrupt, with some cause external
+// Has ajerked us rudely from the Guest's code
+// Again we must return home to the Host
 deliver_to_host:
         SWITCH_TO_HOST
-        /* Decode IDT and jump to hosts' irq handler.  When that does iret, it
-         * will return to run_guest_once.  This is a feature. */
+        // But now we must go home via that place
+        // Where that interrupt was supposed to go
+        // Had we not been ensconced, running the Guest.
+        // Here we see the cleverness of our stack:
+        // The Host stack is formed like an interrupt
+        // With EIP, CS and EFLAGS layered.
+        // Interrupt handlers end with "iret"
+        // And that will take us home at long long last.
+
+        // But first we must find the handler to call!
+        // The IDT descriptor for the Host
+        // Has two bytes for size, and four for address:
+        // %edx will hold it for us for now.
         movl    (LGUEST_PAGES_host_idt_desc+2)(%eax), %edx
+        // We now know the table address we need,
+        // And saved the trap's number inside %ebx.
+        // Yet the pointer to the handler is smeared
+        // Across the bits of the table entry.
+        // What oracle can tell us how to extract
+        // From such a convoluted encoding?
+        // I consulted gcc, and it gave
+        // These instructions, which I gladly credit:
         leal    (%edx,%ebx,8), %eax
         movzwl  (%eax),%edx
         movl    4(%eax), %eax
         xorw    %ax, %ax
         orl     %eax, %edx
+        // Now the address of the handler's in %edx
+        // We call it now: its "iret" takes us home.
         jmp     *%edx
 
-/* Real hardware interrupts are delivered straight to the host.  Others
-   cause us to return to run_guest_once so it can decide what to do.  Note
-   that some of these are overridden by the guest to deliver directly, and
-   never enter here (see load_guest_idt_entry). */
+// Every interrupt can come to us here
+// But we must truly tell each apart.
+// They number two hundred and fifty six
+// And each must land in a different spot,
+// Push its number on stack, and join the stream.
+
+// And worse, a mere six of the traps stand apart
+// And push on their stack an addition:
+// An error number, thirty two bits long
+// So we punish the other two fifty
+// And make them push a zero so they match.
+
+// Yet two fifty six entries is long
+// And all will look most the same as the last
+// So we create a macro which can make
+// As many entries as we need to fill.
+
+// Note the change to .data then .text:
+// We plant the address of each entry
+// Into a (data) table for the Host
+// To know where each Guest interrupt should go.
 .macro IRQ_STUB N TARGET
         .data; .long 1f; .text; 1:
- /* Make an error number for most traps, which don't have one. */
+ // Trap eight, ten through fourteen and seventeen
+ // Supply an error number.  Else zero.
  .if (\N <> 8) && (\N < 10 || \N > 14) && (\N <> 17)
         pushl   $0
  .endif
@@ -128,6 +295,8 @@ deliver_to_host:
         ALIGN
 .endm
 
+// This macro creates numerous entries
+// Using GAS macros which out-power C's.
 .macro IRQ_STUBS FIRST LAST TARGET
  irq=\FIRST
  .rept \LAST-\FIRST+1
@@ -136,24 +305,43 @@ deliver_to_host:
  .endr
 .endm
 
-/* We intercept every interrupt, because we may need to switch back to
- * host.  Unfortunately we can't tell them apart except by entry
- * point, so we need 256 entry points.
- */
+// Here's the marker for our pointer table
+// Laid in the data section just before
+// Each macro places the address of code
+// Forming an array: each one points to text
+// Which handles interrupt in its turn.
 .data
 .global default_idt_entries
 default_idt_entries:
 .text
-        IRQ_STUBS 0 1 return_to_host            /* First two traps */
-        IRQ_STUB 2 handle_nmi                   /* NMI */
-        IRQ_STUBS 3 31 return_to_host           /* Rest of traps */
-        IRQ_STUBS 32 127 deliver_to_host        /* Real interrupts */
-        IRQ_STUB 128 return_to_host             /* System call (overridden) */
-        IRQ_STUBS 129 255 deliver_to_host       /* Other real interrupts */
-
-/* We ignore NMI and return. */
+        // The first two traps go straight back to the Host
+        IRQ_STUBS 0 1 return_to_host
+        // We'll say nothing, yet, about NMI
+        IRQ_STUB 2 handle_nmi
+        // Other traps also return to the Host
+        IRQ_STUBS 3 31 return_to_host
+        // All interrupts go via their handlers
+        IRQ_STUBS 32 127 deliver_to_host
+        // 'Cept system calls coming from userspace
+        // Are to go to the Guest, never the Host.
+        IRQ_STUB 128 return_to_host
+        IRQ_STUBS 129 255 deliver_to_host
+
+// The NMI, what a fabulous beast
+// Which swoops in and stops us no matter that
+// We're suspended between heaven and hell,
+// (Or more likely between the Host and Guest)
+// When in it comes!  We are dazed and confused
+// So we do the simplest thing which one can.
+// Though we've pushed the trap number and zero
+// We discard them, return, and hope we live.
 handle_nmi:
         addl    $8, %esp
         iret
 
+// We are done; all that's left is Mastery
+// And "make Mastery" is a journey long
+// Designed to make your fingers itch to code.
+
+// Here ends the text, the file and poem.
 ENTRY(end_switcher_text)
diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index 9dcbffd0aa15..e204e7b4028a 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -509,7 +509,7 @@ config VIDEO_VINO
 
 config VIDEO_STRADIS
         tristate "Stradis 4:2:2 MPEG-2 video driver  (EXPERIMENTAL)"
-        depends on EXPERIMENTAL && PCI && VIDEO_V4L1 && !PPC64
+        depends on EXPERIMENTAL && PCI && VIDEO_V4L1 && VIRT_TO_BUS
         help
           Say Y here to enable support for the Stradis 4:2:2 MPEG-2 video
           driver for PCI.  There is a product page at
@@ -520,7 +520,7 @@ config VIDEO_ZORAN_ZR36060
 
 config VIDEO_ZORAN
         tristate "Zoran ZR36057/36067 Video For Linux"
-        depends on PCI && I2C_ALGOBIT && VIDEO_V4L1 && !PPC64
+        depends on PCI && I2C_ALGOBIT && VIDEO_V4L1 && VIRT_TO_BUS
         help
           Say Y for support for MJPEG capture cards based on the Zoran
           36057/36067 PCI controller chipset. This includes the Iomega
diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index f88ebc5b685e..cc6c73442435 100644
--- a/drivers/mtd/maps/Kconfig
+++ b/drivers/mtd/maps/Kconfig
@@ -103,7 +103,7 @@ config MTD_PMC_MSP_RAMROOT
 
 config MTD_SUN_UFLASH
         tristate "Sun Microsystems userflash support"
-        depends on SPARC && MTD_CFI
+        depends on SPARC && MTD_CFI && PCI
         help
           This provides a 'mapping' driver which supports the way in
           which user-programmable flash chips are connected on various
diff --git a/drivers/net/ax88796.c b/drivers/net/ax88796.c
index 1d882360b34d..e43e8047b90e 100644
--- a/drivers/net/ax88796.c
+++ b/drivers/net/ax88796.c
@@ -819,7 +819,7 @@ static int ax_probe(struct platform_device *pdev)
         }
 
         ei_status.mem = ioremap(res->start, size);
-        dev->base_addr = (long)ei_status.mem;
+        dev->base_addr = (unsigned long)ei_status.mem;
 
         if (ei_status.mem == NULL) {
                 dev_err(&pdev->dev, "Cannot ioremap area (%08zx,%08zx)\n",
diff --git a/drivers/net/cxgb3/cxgb3_offload.c b/drivers/net/cxgb3/cxgb3_offload.c
index ebcf35e4cf5b..e620ed4c3ff0 100644
--- a/drivers/net/cxgb3/cxgb3_offload.c
+++ b/drivers/net/cxgb3/cxgb3_offload.c
@@ -699,7 +699,7 @@ static int do_cr(struct t3cdev *dev, struct sk_buff *skb)
  * the buffer.
  */
 static struct sk_buff *cxgb3_get_cpl_reply_skb(struct sk_buff *skb, size_t len,
-                                               int gfp)
+                                               gfp_t gfp)
 {
         if (likely(!skb_cloned(skb))) {
                 BUG_ON(skb->len < len);
diff --git a/drivers/net/lguest_net.c b/drivers/net/lguest_net.c
index 112778652f7d..cab57911a80e 100644
--- a/drivers/net/lguest_net.c
+++ b/drivers/net/lguest_net.c
@@ -1,6 +1,13 @@
-/* A simple network driver for lguest.
+/*D:500
+ * The Guest network driver.
  *
- * Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
+ * This is very simple a virtual network driver, and our last Guest driver.
+ * The only trick is that it can talk directly to multiple other recipients
+ * (ie. other Guests on the same network).  It can also be used with only the
+ * Host on the network.
+ :*/
+
+/* Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -28,23 +35,47 @@
 #define MAX_LANS                4
 #define NUM_SKBS                8
 
+/*M:011 Network code master Jeff Garzik points out numerous shortcomings in
+ * this driver if it aspires to greatness.
+ *
+ * Firstly, it doesn't use "NAPI": the networking's New API, and is poorer for
+ * it.  As he says "NAPI means system-wide load leveling, across multiple
+ * network interfaces.  Lack of NAPI can mean competition at higher loads."
+ *
+ * He also points out that we don't implement set_mac_address, so users cannot
+ * change the devices hardware address.  When I asked why one would want to:
+ * "Bonding, and situations where you /do/ want the MAC address to "leak" out
+ * of the host onto the wider net."
+ *
+ * Finally, he would like module unloading: "It is not unrealistic to think of
+ * [un|re|]loading the net support module in an lguest guest.  And, adding
+ * module support makes the programmer more responsible, because they now have
+ * to learn to clean up after themselves.  Any driver that cannot clean up
+ * after itself is an incomplete driver in my book."
+ :*/
+
+/*D:530 The "struct lguestnet_info" contains all the information we need to
+ * know about the network device. */
 struct lguestnet_info
 {
-        /* The shared page(s). */
+        /* The mapped device page(s) (an array of "struct lguest_net"). */
         struct lguest_net *peer;
+        /* The physical address of the device page(s) */
         unsigned long peer_phys;
+        /* The size of the device page(s). */
         unsigned long mapsize;
 
         /* The lguest_device I come from */
         struct lguest_device *lgdev;
 
-        /* My peerid. */
+        /* My peerid (ie. my slot in the array). */
         unsigned int me;
 
-        /* Receive queue. */
+        /* Receive queue: the network packets waiting to be filled. */
         struct sk_buff *skb[NUM_SKBS];
         struct lguest_dma dma[NUM_SKBS];
 };
+/*:*/
 
 /* How many bytes left in this page. */
 static unsigned int rest_of_page(void *data)
@@ -52,39 +83,82 @@ static unsigned int rest_of_page(void *data)
         return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE);
 }
 
-/* Simple convention: offset 4 * peernum. */
+/*D:570 Each peer (ie. Guest or Host) on the network binds their receive
+ * buffers to a different key: we simply use the physical address of the
+ * device's memory page plus the peer number.  The Host insists that all keys
+ * be a multiple of 4, so we multiply the peer number by 4. */
 static unsigned long peer_key(struct lguestnet_info *info, unsigned peernum)
 {
         return info->peer_phys + 4 * peernum;
 }
 
+/* This is the routine which sets up a "struct lguest_dma" to point to a
+ * network packet, similar to req_to_dma() in lguest_blk.c.  The structure of a
+ * "struct sk_buff" has grown complex over the years: it consists of a "head"
+ * linear section pointed to by "skb->data", and possibly an array of
+ * "fragments" in the case of a non-linear packet.
+ *
+ * Our receive buffers don't use fragments at all but outgoing skbs might, so
+ * we handle it. */
 static void skb_to_dma(const struct sk_buff *skb, unsigned int headlen,
                        struct lguest_dma *dma)
 {
         unsigned int i, seg;
 
+        /* First, we put the linear region into the "struct lguest_dma".  Each
+         * entry can't go over a page boundary, so even though all our packets
+         * are 1514 bytes or less, we might need to use two entries here: */
         for (i = seg = 0; i < headlen; seg++, i += rest_of_page(skb->data+i)) {
                 dma->addr[seg] = virt_to_phys(skb->data + i);
                 dma->len[seg] = min((unsigned)(headlen - i),
                                     rest_of_page(skb->data + i));
         }
+
+        /* Now we handle the fragments: at least they're guaranteed not to go
+         * over a page.  skb_shinfo(skb) returns a pointer to the structure
+         * which tells us about the number of fragments and the fragment
+         * array. */
         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++, seg++) {
                 const skb_frag_t *f = &skb_shinfo(skb)->frags[i];
                 /* Should not happen with MTU less than 64k - 2 * PAGE_SIZE. */
                 if (seg == LGUEST_MAX_DMA_SECTIONS) {
+                        /* We will end up sending a truncated packet should
+                         * this ever happen.  Plus, a cool log message! */
                         printk("Woah dude!  Megapacket!\n");
                         break;
                 }
                 dma->addr[seg] = page_to_phys(f->page) + f->page_offset;
                 dma->len[seg] = f->size;
         }
+
+        /* If after all that we didn't use the entire "struct lguest_dma"
+         * array, we terminate it with a 0 length. */
         if (seg < LGUEST_MAX_DMA_SECTIONS)
                 dma->len[seg] = 0;
 }
 
-/* We overload multicast bit to show promiscuous mode. */
+/*
+ * Packet transmission.
+ *
+ * Our packet transmission is a little unusual.  A real network card would just
+ * send out the packet and leave the receivers to decide if they're interested.
+ * Instead, we look through the network device memory page and see if any of
+ * the ethernet addresses match the packet destination, and if so we send it to
+ * that Guest.
+ *
+ * This is made a little more complicated in two cases.  The first case is
+ * broadcast packets: for that we send the packet to all Guests on the network,
+ * one at a time.  The second case is "promiscuous" mode, where a Guest wants
+ * to see all the packets on the network.  We need a way for the Guest to tell
+ * us it wants to see all packets, so it sets the "multicast" bit on its
+ * published MAC address, which is never valid in a real ethernet address.
+ */
 #define PROMISC_BIT             0x01
 
+/* This is the callback which is summoned whenever the network device's
+ * multicast or promiscuous state changes.  If the card is in promiscuous mode,
+ * we advertise that in our ethernet address in the device's memory.  We do the
+ * same if Linux wants any or all multicast traffic.  */
 static void lguestnet_set_multicast(struct net_device *dev)
 {
         struct lguestnet_info *info = netdev_priv(dev);
@@ -95,11 +169,14 @@ static void lguestnet_set_multicast(struct net_device *dev)
                 info->peer[info->me].mac[0] &= ~PROMISC_BIT;
 }
 
+/* A simple test function to see if a peer wants to see all packets.*/
 static int promisc(struct lguestnet_info *info, unsigned int peer)
 {
         return info->peer[peer].mac[0] & PROMISC_BIT;
 }
 
+/* Another simple function to see if a peer's advertised ethernet address
+ * matches a packet's destination ethernet address. */
 static int mac_eq(const unsigned char mac[ETH_ALEN],
                   struct lguestnet_info *info, unsigned int peer)
 {
@@ -109,6 +186,8 @@ static int mac_eq(const unsigned char mac[ETH_ALEN],
         return memcmp(mac+1, info->peer[peer].mac+1, ETH_ALEN-1) == 0;
 }
 
+/* This is the function which actually sends a packet once we've decided a
+ * peer wants it: */
 static void transfer_packet(struct net_device *dev,
                             struct sk_buff *skb,
                             unsigned int peernum)
@@ -116,76 +195,134 @@ static void transfer_packet(struct net_device *dev,
         struct lguestnet_info *info = netdev_priv(dev);
         struct lguest_dma dma;
 
+        /* We use our handy "struct lguest_dma" packing function to prepare
+         * the skb for sending. */
         skb_to_dma(skb, skb_headlen(skb), &dma);
         pr_debug("xfer length %04x (%u)\n", htons(skb->len), skb->len);
 
+        /* This is the actual send call which copies the packet. */
         lguest_send_dma(peer_key(info, peernum), &dma);
+
+        /* Check that the entire packet was transmitted.  If not, it could mean
+         * that the other Guest registered a short receive buffer, but this
+         * driver should never do that.  More likely, the peer is dead. */
         if (dma.used_len != skb->len) {
                 dev->stats.tx_carrier_errors++;
                 pr_debug("Bad xfer to peer %i: %i of %i (dma %p/%i)\n",
                          peernum, dma.used_len, skb->len,
                          (void *)dma.addr[0], dma.len[0]);
         } else {
+                /* On success we update the stats. */
                 dev->stats.tx_bytes += skb->len;
                 dev->stats.tx_packets++;
         }
 }
 
+/* Another helper function to tell is if a slot in the device memory is unused.
+ * Since we always set the Local Assignment bit in the ethernet address, the
+ * first byte can never be 0. */
 static int unused_peer(const struct lguest_net peer[], unsigned int num)
 {
         return peer[num].mac[0] == 0;
 }
 
+/* Finally, here is the routine which handles an outgoing packet.  It's called
+ * "start_xmit" for traditional reasons. */
 static int lguestnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         unsigned int i;
         int broadcast;
         struct lguestnet_info *info = netdev_priv(dev);
+        /* Extract the destination ethernet address from the packet. */
         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
 
         pr_debug("%s: xmit %02x:%02x:%02x:%02x:%02x:%02x\n",
                  dev->name, dest[0],dest[1],dest[2],dest[3],dest[4],dest[5]);
 
+        /* If it's a multicast packet, we broadcast to everyone.  That's not
+         * very efficient, but there are very few applications which actually
+         * use multicast, which is a shame really.
+         *
+         * As etherdevice.h points out: "By definition the broadcast address is
+         * also a multicast address."  So we don't have to test for broadcast
+         * packets separately. */
         broadcast = is_multicast_ether_addr(dest);
+
+        /* Look through all the published ethernet addresses to see if we
+         * should send this packet. */
         for (i = 0; i < info->mapsize/sizeof(struct lguest_net); i++) {
+                /* We don't send to ourselves (we actually can't SEND_DMA to
+                 * ourselves anyway), and don't send to unused slots.*/
                 if (i == info->me || unused_peer(info->peer, i))
                         continue;
 
+                /* If it's broadcast we send it.  If they want every packet we
+                 * send it.  If the destination matches their address we send
+                 * it.  Otherwise we go to the next peer. */
                 if (!broadcast && !promisc(info, i) && !mac_eq(dest, info, i))
                         continue;
 
                 pr_debug("lguestnet %s: sending from %i to %i\n",
                          dev->name, info->me, i);
+                /* Our routine which actually does the transfer. */
                 transfer_packet(dev, skb, i);
         }
+
+        /* An xmit routine is expected to dispose of the packet, so we do. */
         dev_kfree_skb(skb);
+
+        /* As per kernel convention, 0 means success.  This is why I love
+         * networking: even if we never sent to anyone, that's still
+         * success! */
         return 0;
 }
 
-/* Find a new skb to put in this slot in shared mem. */
+/*D:560
+ * Packet receiving.
+ *
+ * First, here's a helper routine which fills one of our array of receive
+ * buffers: */
 static int fill_slot(struct net_device *dev, unsigned int slot)
 {
         struct lguestnet_info *info = netdev_priv(dev);
-        /* Try to create and register a new one. */
+
+        /* We can receive ETH_DATA_LEN (1500) byte packets, plus a standard
+         * ethernet header of ETH_HLEN (14) bytes. */
         info->skb[slot] = netdev_alloc_skb(dev, ETH_HLEN + ETH_DATA_LEN);
         if (!info->skb[slot]) {
                 printk("%s: could not fill slot %i\n", dev->name, slot);
                 return -ENOMEM;
         }
 
+        /* skb_to_dma() is a helper which sets up the "struct lguest_dma" to
+         * point to the data in the skb: we also use it for sending out a
+         * packet. */
         skb_to_dma(info->skb[slot], ETH_HLEN + ETH_DATA_LEN, &info->dma[slot]);
+
+        /* This is a Write Memory Barrier: it ensures that the entry in the
+         * receive buffer array is written *before* we set the "used_len" entry
+         * to 0.  If the Host were looking at the receive buffer array from a
+         * different CPU, it could potentially see "used_len = 0" and not see
+         * the updated receive buffer information.  This would be a horribly
+         * nasty bug, so make sure the compiler and CPU know this has to happen
+         * first. */
         wmb();
-        /* Now we tell hypervisor it can use the slot. */
+        /* Writing 0 to "used_len" tells the Host it can use this receive
+         * buffer now. */
         info->dma[slot].used_len = 0;
         return 0;
 }
 
+/* This is the actual receive routine.  When we receive an interrupt from the
+ * Host to tell us a packet has been delivered, we arrive here: */
 static irqreturn_t lguestnet_rcv(int irq, void *dev_id)
 {
         struct net_device *dev = dev_id;
         struct lguestnet_info *info = netdev_priv(dev);
         unsigned int i, done = 0;
 
+        /* Look through our entire receive array for an entry which has data
+         * in it. */
         for (i = 0; i < ARRAY_SIZE(info->dma); i++) {
                 unsigned int length;
                 struct sk_buff *skb;
@@ -194,10 +331,16 @@ static irqreturn_t lguestnet_rcv(int irq, void *dev_id)
                 if (length == 0)
                         continue;
 
+                /* We've found one!  Remember the skb (we grabbed the length
+                 * above), and immediately refill the slot we've taken it
+                 * from. */
                 done++;
                 skb = info->skb[i];
                 fill_slot(dev, i);
 
+                /* This shouldn't happen: micropackets could be sent by a
+                 * badly-behaved Guest on the network, but the Host will never
+                 * stuff more data in the buffer than the buffer length. */
                 if (length < ETH_HLEN || length > ETH_HLEN + ETH_DATA_LEN) {
                         pr_debug(KERN_WARNING "%s: unbelievable skb len: %i\n",
                                  dev->name, length);
@@ -205,36 +348,72 @@ static irqreturn_t lguestnet_rcv(int irq, void *dev_id)
                         continue;
                 }
 
+                /* skb_put(), what a great function!  I've ranted about this
+                 * function before (http://lkml.org/lkml/1999/9/26/24).  You
+                 * call it after you've added data to the end of an skb (in
+                 * this case, it was the Host which wrote the data). */
                 skb_put(skb, length);
+
+                /* The ethernet header contains a protocol field: we use the
+                 * standard helper to extract it, and place the result in
+                 * skb->protocol.  The helper also sets up skb->pkt_type and
+                 * eats up the ethernet header from the front of the packet. */
                 skb->protocol = eth_type_trans(skb, dev);
-                /* This is a reliable transport. */
+
+                /* If this device doesn't need checksums for sending, we also
+                 * don't need to check the packets when they come in. */
                 if (dev->features & NETIF_F_NO_CSUM)
                         skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+                /* As a last resort for debugging the driver or the lguest I/O
+                 * subsystem, you can uncomment the "#define DEBUG" at the top
+                 * of this file, which turns all the pr_debug() into printk()
+                 * and floods the logs. */
                 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
                          ntohs(skb->protocol), skb->len, skb->pkt_type);
 
+                /* Update the packet and byte counts (visible from ifconfig,
+                 * and good for debugging). */
                 dev->stats.rx_bytes += skb->len;
                 dev->stats.rx_packets++;
+
+                /* Hand our fresh network packet into the stack's "network
+                 * interface receive" routine.  That will free the packet
+                 * itself when it's finished. */
                 netif_rx(skb);
         }
+
+        /* If we found any packets, we assume the interrupt was for us. */
         return done ? IRQ_HANDLED : IRQ_NONE;
 }
 
+/*D:550 This is where we start: when the device is brought up by dhcpd or
+ * ifconfig.  At this point we advertise our MAC address to the rest of the
+ * network, and register receive buffers ready for incoming packets. */
 static int lguestnet_open(struct net_device *dev)
 {
         int i;
         struct lguestnet_info *info = netdev_priv(dev);
 
-        /* Set up our MAC address */
+        /* Copy our MAC address into the device page, so others on the network
+         * can find us. */
         memcpy(info->peer[info->me].mac, dev->dev_addr, ETH_ALEN);
 
-        /* Turn on promisc mode if needed */
+        /* We might already be in promisc mode (dev->flags & IFF_PROMISC).  Our
+         * set_multicast callback handles this already, so we call it now. */
         lguestnet_set_multicast(dev);
 
+        /* Allocate packets and put them into our "struct lguest_dma" array.
+         * If we fail to allocate all the packets we could still limp along,
+         * but it's a sign of real stress so we should probably give up now. */
         for (i = 0; i < ARRAY_SIZE(info->dma); i++) {
                 if (fill_slot(dev, i) != 0)
                         goto cleanup;
         }
+
+        /* Finally we tell the Host where our array of "struct lguest_dma"
+         * receive buffers is, binding it to the key corresponding to the
+         * device's physical memory plus our peerid. */
         if (lguest_bind_dma(peer_key(info,info->me), info->dma,
                             NUM_SKBS, lgdev_irq(info->lgdev)) != 0)
                 goto cleanup;
@@ -245,22 +424,29 @@ cleanup:
                 dev_kfree_skb(info->skb[i]);
         return -ENOMEM;
 }
+/*:*/
 
+/* The close routine is called when the device is no longer in use: we clean up
+ * elegantly. */
 static int lguestnet_close(struct net_device *dev)
 {
         unsigned int i;
         struct lguestnet_info *info = netdev_priv(dev);
 
-        /* Clear all trace: others might deliver packets, we'll ignore it. */
+        /* Clear all trace of our existence out of the device memory by setting
+         * the slot which held our MAC address to 0 (unused). */
         memset(&info->peer[info->me], 0, sizeof(info->peer[info->me]));
 
-        /* Deregister sg lists. */
+        /* Unregister our array of receive buffers */
         lguest_unbind_dma(peer_key(info, info->me), info->dma);
         for (i = 0; i < ARRAY_SIZE(info->dma); i++)
                 dev_kfree_skb(info->skb[i]);
         return 0;
 }
 
+/*D:510 The network device probe function is basically a standard ethernet
+ * device setup.  It reads the "struct lguest_device_desc" and sets the "struct
+ * net_device".  Oh, the line-by-line excitement!  Let's skip over it. :*/
 static int lguestnet_probe(struct lguest_device *lgdev)
 {
         int err, irqf = IRQF_SHARED;
@@ -290,10 +476,16 @@ static int lguestnet_probe(struct lguest_device *lgdev)
         dev->stop = lguestnet_close;
         dev->hard_start_xmit = lguestnet_start_xmit;
 
-        /* Turning on/off promisc will call dev->set_multicast_list.
-         * We don't actually support multicast yet */
+        /* We don't actually support multicast yet, but turning on/off
+         * promisc also calls dev->set_multicast_list. */
         dev->set_multicast_list = lguestnet_set_multicast;
         SET_NETDEV_DEV(dev, &lgdev->dev);
+
+        /* The network code complains if you have "scatter-gather" capability
+         * if you don't also handle checksums (it seem that would be
+         * "illogical").  So we use a lie of omission and don't tell it that we
+         * can handle scattered packets unless we also don't want checksums,
+         * even though to us they're completely independent. */
         if (desc->features & LGUEST_NET_F_NOCSUM)
                 dev->features = NETIF_F_SG|NETIF_F_NO_CSUM;
 
@@ -325,6 +517,9 @@ static int lguestnet_probe(struct lguest_device *lgdev)
         }
 
         pr_debug("lguestnet: registered device %s\n", dev->name);
+        /* Finally, we put the "struct net_device" in the generic "struct
+         * lguest_device"s private pointer.  Again, it's not necessary, but
+         * makes sure the cool kernel kids don't tease us. */
         lgdev->private = dev;
         return 0;
 
@@ -352,3 +547,11 @@ module_init(lguestnet_init);
 
 MODULE_DESCRIPTION("Lguest network driver");
 MODULE_LICENSE("GPL");
+
+/*D:580
+ * This is the last of the Drivers, and with this we have covered the many and
+ * wonderous and fine (and boring) details of the Guest.
+ *
+ * "make Launcher" beckons, where we answer questions like "Where do Guests
+ * come from?", and "What do you do when someone asks for optimization?"
+ */
diff --git a/drivers/net/lib8390.c b/drivers/net/lib8390.c
index 5c86e737f954..721ee38d2241 100644
--- a/drivers/net/lib8390.c
+++ b/drivers/net/lib8390.c
@@ -219,15 +219,6 @@ static void ei_tx_timeout(struct net_device *dev)
         int txsr, isr, tickssofar = jiffies - dev->trans_start;
         unsigned long flags;
 
-#if defined(CONFIG_M32R) && defined(CONFIG_SMP)
-        unsigned long icucr;
-
-        local_irq_save(flags);
-        icucr = inl(M32R_ICU_CR1_PORTL);
-        icucr |= M32R_ICUCR_ISMOD11;
-        outl(icucr, M32R_ICU_CR1_PORTL);
-        local_irq_restore(flags);
-#endif
         ei_local->stat.tx_errors++;
 
         spin_lock_irqsave(&ei_local->page_lock, flags);
diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c
index f87176055d0e..266e8b38fe10 100644
--- a/drivers/net/pppol2tp.c
+++ b/drivers/net/pppol2tp.c
@@ -2054,7 +2054,7 @@ end:
  */
 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
                                       struct pppol2tp_tunnel *tunnel,
-                                      int optname, int __user *val)
+                                      int optname, int *val)
 {
         int err = 0;
 
@@ -2077,7 +2077,7 @@ static int pppol2tp_tunnel_getsockopt(struct sock *sk,
  */
 static int pppol2tp_session_getsockopt(struct sock *sk,
                                        struct pppol2tp_session *session,
-                                       int optname, int __user *val)
+                                       int optname, int *val)
 {
         int err = 0;
 
diff --git a/drivers/pnp/card.c b/drivers/pnp/card.c
index dd6384b1efce..b6a4f02b01d1 100644
--- a/drivers/pnp/card.c
+++ b/drivers/pnp/card.c
@@ -2,7 +2,6 @@
  * card.c - contains functions for managing groups of PnP devices
  *
  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/module.h>
@@ -13,26 +12,31 @@
 LIST_HEAD(pnp_cards);
 static LIST_HEAD(pnp_card_drivers);
 
-
-static const struct pnp_card_device_id * match_card(struct pnp_card_driver * drv, struct pnp_card * card)
+static const struct pnp_card_device_id *match_card(struct pnp_card_driver *drv,
+                                                   struct pnp_card *card)
 {
-        const struct pnp_card_device_id * drv_id = drv->id_table;
-        while (*drv_id->id){
-                if (compare_pnp_id(card->id,drv_id->id)) {
+        const struct pnp_card_device_id *drv_id = drv->id_table;
+
+        while (*drv_id->id) {
+                if (compare_pnp_id(card->id, drv_id->id)) {
                         int i = 0;
+
                         for (;;) {
                                 int found;
                                 struct pnp_dev *dev;
-                                if (i == PNP_MAX_DEVICES || ! *drv_id->devs[i].id)
+
+                                if (i == PNP_MAX_DEVICES
+                                    || !*drv_id->devs[i].id)
                                         return drv_id;
                                 found = 0;
                                 card_for_each_dev(card, dev) {
-                                        if (compare_pnp_id(dev->id, drv_id->devs[i].id)) {
+                                        if (compare_pnp_id
+                                            (dev->id, drv_id->devs[i].id)) {
                                                 found = 1;
                                                 break;
                                         }
                                 }
-                                if (! found)
+                                if (!found)
                                         break;
                                 i++;
                         }
@@ -42,14 +46,15 @@ static const struct pnp_card_device_id * match_card(struct pnp_card_driver * drv
         return NULL;
 }
 
-static void card_remove(struct pnp_dev * dev)
+static void card_remove(struct pnp_dev *dev)
 {
         dev->card_link = NULL;
 }
 
-static void card_remove_first(struct pnp_dev * dev)
+static void card_remove_first(struct pnp_dev *dev)
 {
-        struct pnp_card_driver * drv = to_pnp_card_driver(dev->driver);
+        struct pnp_card_driver *drv = to_pnp_card_driver(dev->driver);
+
         if (!dev->card || !drv)
                 return;
         if (drv->remove)
@@ -67,7 +72,7 @@ static int card_probe(struct pnp_card *card, struct pnp_card_driver *drv)
 
         if (!drv->probe)
                 return 0;
-        id = match_card(drv,card);
+        id = match_card(drv, card);
         if (!id)
                 return 0;
 
@@ -94,12 +99,11 @@ static int card_probe(struct pnp_card *card, struct pnp_card_driver *drv)
  * pnp_add_card_id - adds an EISA id to the specified card
  * @id: pointer to a pnp_id structure
  * @card: pointer to the desired card
- *
  */
-
-int pnp_add_card_id(struct pnp_id *id, struct pnp_card * card)
+int pnp_add_card_id(struct pnp_id *id, struct pnp_card *card)
 {
-        struct pnp_id * ptr;
+        struct pnp_id *ptr;
+
         if (!id)
                 return -EINVAL;
         if (!card)
@@ -115,10 +119,11 @@ int pnp_add_card_id(struct pnp_id *id, struct pnp_card * card)
         return 0;
 }
 
-static void pnp_free_card_ids(struct pnp_card * card)
+static void pnp_free_card_ids(struct pnp_card *card)
 {
-        struct pnp_id * id;
+        struct pnp_id *id;
         struct pnp_id *next;
+
         if (!card)
                 return;
         id = card->id;
@@ -131,49 +136,55 @@ static void pnp_free_card_ids(struct pnp_card * card)
 
 static void pnp_release_card(struct device *dmdev)
 {
-        struct pnp_card * card = to_pnp_card(dmdev);
+        struct pnp_card *card = to_pnp_card(dmdev);
+
         pnp_free_card_ids(card);
         kfree(card);
 }
 
-
-static ssize_t pnp_show_card_name(struct device *dmdev, struct device_attribute *attr, char *buf)
+static ssize_t pnp_show_card_name(struct device *dmdev,
+                                  struct device_attribute *attr, char *buf)
 {
         char *str = buf;
         struct pnp_card *card = to_pnp_card(dmdev);
-        str += sprintf(str,"%s\n", card->name);
+
+        str += sprintf(str, "%s\n", card->name);
         return (str - buf);
 }
 
-static DEVICE_ATTR(name,S_IRUGO,pnp_show_card_name,NULL);
+static DEVICE_ATTR(name, S_IRUGO, pnp_show_card_name, NULL);
 
-static ssize_t pnp_show_card_ids(struct device *dmdev, struct device_attribute *attr, char *buf)
+static ssize_t pnp_show_card_ids(struct device *dmdev,
+                                 struct device_attribute *attr, char *buf)
 {
         char *str = buf;
         struct pnp_card *card = to_pnp_card(dmdev);
-        struct pnp_id * pos = card->id;
+        struct pnp_id *pos = card->id;
 
         while (pos) {
-                str += sprintf(str,"%s\n", pos->id);
+                str += sprintf(str, "%s\n", pos->id);
                 pos = pos->next;
         }
         return (str - buf);
 }
 
-static DEVICE_ATTR(card_id,S_IRUGO,pnp_show_card_ids,NULL);
+static DEVICE_ATTR(card_id, S_IRUGO, pnp_show_card_ids, NULL);
 
 static int pnp_interface_attach_card(struct pnp_card *card)
 {
-        int rc = device_create_file(&card->dev,&dev_attr_name);
-        if (rc) return rc;
+        int rc = device_create_file(&card->dev, &dev_attr_name);
 
-        rc = device_create_file(&card->dev,&dev_attr_card_id);
-        if (rc) goto err_name;
+        if (rc)
+                return rc;
+
+        rc = device_create_file(&card->dev, &dev_attr_card_id);
+        if (rc)
+                goto err_name;
 
         return 0;
 
-err_name:
-        device_remove_file(&card->dev,&dev_attr_name);
+      err_name:
+        device_remove_file(&card->dev, &dev_attr_name);
         return rc;
 }
 
@@ -181,15 +192,16 @@ err_name:
  * pnp_add_card - adds a PnP card to the PnP Layer
  * @card: pointer to the card to add
  */
-
-int pnp_add_card(struct pnp_card * card)
+int pnp_add_card(struct pnp_card *card)
 {
         int error;
-        struct list_head * pos, * temp;
+        struct list_head *pos, *temp;
+
         if (!card || !card->protocol)
                 return -EINVAL;
 
-        sprintf(card->dev.bus_id, "%02x:%02x", card->protocol->number, card->number);
+        sprintf(card->dev.bus_id, "%02x:%02x", card->protocol->number,
+                card->number);
         card->dev.parent = &card->protocol->dev;
         card->dev.bus = NULL;
         card->dev.release = &pnp_release_card;
@@ -205,18 +217,21 @@ int pnp_add_card(struct pnp_card * card)
                 /* we wait until now to add devices in order to ensure the drivers
                  * will be able to use all of the related devices on the card
                  * without waiting any unresonable length of time */
-                list_for_each(pos,&card->devices){
+                list_for_each(pos, &card->devices) {
                         struct pnp_dev *dev = card_to_pnp_dev(pos);
                         __pnp_add_device(dev);
                 }
 
                 /* match with card drivers */
-                list_for_each_safe(pos,temp,&pnp_card_drivers){
-                        struct pnp_card_driver * drv = list_entry(pos, struct pnp_card_driver, global_list);
-                        card_probe(card,drv);
+                list_for_each_safe(pos, temp, &pnp_card_drivers) {
+                        struct pnp_card_driver *drv =
+                            list_entry(pos, struct pnp_card_driver,
+                                       global_list);
+                        card_probe(card, drv);
                 }
         } else
-                pnp_err("sysfs failure, card '%s' will be unavailable", card->dev.bus_id);
+                pnp_err("sysfs failure, card '%s' will be unavailable",
+                        card->dev.bus_id);
         return error;
 }
 
@@ -224,10 +239,10 @@ int pnp_add_card(struct pnp_card * card)
  * pnp_remove_card - removes a PnP card from the PnP Layer
  * @card: pointer to the card to remove
  */
-
-void pnp_remove_card(struct pnp_card * card)
+void pnp_remove_card(struct pnp_card *card)
 {
         struct list_head *pos, *temp;
+
         if (!card)
                 return;
         device_unregister(&card->dev);
@@ -235,7 +250,7 @@ void pnp_remove_card(struct pnp_card * card)
         list_del(&card->global_list);
         list_del(&card->protocol_list);
         spin_unlock(&pnp_lock);
-        list_for_each_safe(pos,temp,&card->devices){
+        list_for_each_safe(pos, temp, &card->devices) {
                 struct pnp_dev *dev = card_to_pnp_dev(pos);
                 pnp_remove_card_device(dev);
         }
@@ -246,15 +261,14 @@ void pnp_remove_card(struct pnp_card * card)
  * @card: pointer to the card to add to
  * @dev: pointer to the device to add
  */
-
-int pnp_add_card_device(struct pnp_card * card, struct pnp_dev * dev)
+int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev)
 {
         if (!card || !dev || !dev->protocol)
                 return -EINVAL;
         dev->dev.parent = &card->dev;
         dev->card_link = NULL;
-        snprintf(dev->dev.bus_id, BUS_ID_SIZE, "%02x:%02x.%02x", dev->protocol->number,
-                 card->number,dev->number);
+        snprintf(dev->dev.bus_id, BUS_ID_SIZE, "%02x:%02x.%02x",
+                 dev->protocol->number, card->number, dev->number);
         spin_lock(&pnp_lock);
         dev->card = card;
         list_add_tail(&dev->card_list, &card->devices);
@@ -266,8 +280,7 @@ int pnp_add_card_device(struct pnp_card * card, struct pnp_dev * dev)
  * pnp_remove_card_device- removes a device from the specified card
  * @dev: pointer to the device to remove
  */
-
-void pnp_remove_card_device(struct pnp_dev * dev)
+void pnp_remove_card_device(struct pnp_dev *dev)
 {
         spin_lock(&pnp_lock);
         dev->card = NULL;
@@ -282,13 +295,14 @@ void pnp_remove_card_device(struct pnp_dev * dev)
  * @id: pointer to a PnP ID structure that explains the rules for finding the device
  * @from: Starting place to search from. If NULL it will start from the begining.
  */
-
-struct pnp_dev * pnp_request_card_device(struct pnp_card_link *clink, const char * id, struct pnp_dev * from)
+struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink,
+                                        const char *id, struct pnp_dev *from)
 {
-        struct list_head * pos;
-        struct pnp_dev * dev;
-        struct pnp_card_driver * drv;
-        struct pnp_card * card;
+        struct list_head *pos;
+        struct pnp_dev *dev;
+        struct pnp_card_driver *drv;
+        struct pnp_card *card;
+
         if (!clink || !id)
                 goto done;
         card = clink->card;
@@ -302,15 +316,15 @@ struct pnp_dev * pnp_request_card_device(struct pnp_card_link *clink, const char
         }
         while (pos != &card->devices) {
                 dev = card_to_pnp_dev(pos);
-                if ((!dev->card_link) && compare_pnp_id(dev->id,id))
+                if ((!dev->card_link) && compare_pnp_id(dev->id, id))
                         goto found;
                 pos = pos->next;
         }
 
-done:
+      done:
         return NULL;
 
-found:
+      found:
         dev->card_link = clink;
         dev->dev.driver = &drv->link.driver;
         if (pnp_bus_type.probe(&dev->dev))
@@ -320,7 +334,7 @@ found:
 
         return dev;
 
-err_out:
+      err_out:
         dev->dev.driver = NULL;
         dev->card_link = NULL;
         return NULL;
@@ -330,10 +344,10 @@ err_out:
  * pnp_release_card_device - call this when the driver no longer needs the device
  * @dev: pointer to the PnP device stucture
  */
-
-void pnp_release_card_device(struct pnp_dev * dev)
+void pnp_release_card_device(struct pnp_dev *dev)
 {
-        struct pnp_card_driver * drv = dev->card_link->driver;
+        struct pnp_card_driver *drv = dev->card_link->driver;
+
         if (!drv)
                 return;
         drv->link.remove = &card_remove;
@@ -347,6 +361,7 @@ void pnp_release_card_device(struct pnp_dev * dev)
 static int card_suspend(struct pnp_dev *dev, pm_message_t state)
 {
         struct pnp_card_link *link = dev->card_link;
+
         if (link->pm_state.event == state.event)
                 return 0;
         link->pm_state = state;
@@ -356,6 +371,7 @@ static int card_suspend(struct pnp_dev *dev, pm_message_t state)
 static int card_resume(struct pnp_dev *dev)
 {
         struct pnp_card_link *link = dev->card_link;
+
         if (link->pm_state.event == PM_EVENT_ON)
                 return 0;
         link->pm_state = PMSG_ON;
@@ -367,8 +383,7 @@ static int card_resume(struct pnp_dev *dev)
  * pnp_register_card_driver - registers a PnP card driver with the PnP Layer
  * @drv: pointer to the driver to register
  */
-
-int pnp_register_card_driver(struct pnp_card_driver * drv)
+int pnp_register_card_driver(struct pnp_card_driver *drv)
 {
         int error;
         struct list_head *pos, *temp;
@@ -389,9 +404,10 @@ int pnp_register_card_driver(struct pnp_card_driver * drv)
         list_add_tail(&drv->global_list, &pnp_card_drivers);
         spin_unlock(&pnp_lock);
 
-        list_for_each_safe(pos,temp,&pnp_cards){
-                struct pnp_card *card = list_entry(pos, struct pnp_card, global_list);
-                card_probe(card,drv);
+        list_for_each_safe(pos, temp, &pnp_cards) {
+                struct pnp_card *card =
+                    list_entry(pos, struct pnp_card, global_list);
+                card_probe(card, drv);
         }
         return 0;
 }
@@ -400,8 +416,7 @@ int pnp_register_card_driver(struct pnp_card_driver * drv)
  * pnp_unregister_card_driver - unregisters a PnP card driver from the PnP Layer
  * @drv: pointer to the driver to unregister
  */
-
-void pnp_unregister_card_driver(struct pnp_card_driver * drv)
+void pnp_unregister_card_driver(struct pnp_card_driver *drv)
 {
         spin_lock(&pnp_lock);
         list_del(&drv->global_list);
@@ -409,13 +424,6 @@ void pnp_unregister_card_driver(struct pnp_card_driver * drv)
         pnp_unregister_driver(&drv->link);
 }
 
-#if 0
-EXPORT_SYMBOL(pnp_add_card);
-EXPORT_SYMBOL(pnp_remove_card);
-EXPORT_SYMBOL(pnp_add_card_device);
-EXPORT_SYMBOL(pnp_remove_card_device);
-EXPORT_SYMBOL(pnp_add_card_id);
-#endif  /*  0  */
 EXPORT_SYMBOL(pnp_request_card_device);
 EXPORT_SYMBOL(pnp_release_card_device);
 EXPORT_SYMBOL(pnp_register_card_driver);
diff --git a/drivers/pnp/core.c b/drivers/pnp/core.c
index 8e7b2dd38810..61066fdb9e6d 100644
--- a/drivers/pnp/core.c
+++ b/drivers/pnp/core.c
@@ -2,7 +2,6 @@
  * core.c - contains all core device and protocol registration functions
  *
  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/pnp.h>
@@ -18,7 +17,6 @@
 
 #include "base.h"
 
-
 static LIST_HEAD(pnp_protocols);
 LIST_HEAD(pnp_global);
 DEFINE_SPINLOCK(pnp_lock);
@@ -36,7 +34,7 @@ void *pnp_alloc(long size)
         void *result;
 
         result = kzalloc(size, GFP_KERNEL);
-        if (!result){
+        if (!result) {
                 printk(KERN_ERR "pnp: Out of Memory\n");
                 return NULL;
         }
@@ -49,11 +47,10 @@ void *pnp_alloc(long size)
  *
  *  Ex protocols: ISAPNP, PNPBIOS, etc
  */
-
 int pnp_register_protocol(struct pnp_protocol *protocol)
 {
         int nodenum;
-        struct list_head * pos;
+        struct list_head *pos;
 
         if (!protocol)
                 return -EINVAL;
@@ -64,9 +61,9 @@ int pnp_register_protocol(struct pnp_protocol *protocol)
         spin_lock(&pnp_lock);
 
         /* assign the lowest unused number */
-        list_for_each(pos,&pnp_protocols) {
-                struct pnp_protocol * cur = to_pnp_protocol(pos);
-                if (cur->number == nodenum){
+        list_for_each(pos, &pnp_protocols) {
+                struct pnp_protocol *cur = to_pnp_protocol(pos);
+                if (cur->number == nodenum) {
                         pos = &pnp_protocols;
                         nodenum++;
                 }
@@ -83,7 +80,6 @@ int pnp_register_protocol(struct pnp_protocol *protocol)
 /**
  * pnp_protocol_unregister - removes a pnp protocol from the pnp layer
  * @protocol: pointer to the corresponding pnp_protocol structure
- *
  */
 void pnp_unregister_protocol(struct pnp_protocol *protocol)
 {
@@ -93,11 +89,11 @@ void pnp_unregister_protocol(struct pnp_protocol *protocol)
         device_unregister(&protocol->dev);
 }
 
-
 static void pnp_free_ids(struct pnp_dev *dev)
 {
-        struct pnp_id * id;
-        struct pnp_id * next;
+        struct pnp_id *id;
+        struct pnp_id *next;
+
         if (!dev)
                 return;
         id = dev->id;
@@ -110,7 +106,8 @@ static void pnp_free_ids(struct pnp_dev *dev)
 
 static void pnp_release_device(struct device *dmdev)
 {
-        struct pnp_dev * dev = to_pnp_dev(dmdev);
+        struct pnp_dev *dev = to_pnp_dev(dmdev);
+
         pnp_free_option(dev->independent);
         pnp_free_option(dev->dependent);
         pnp_free_ids(dev);
@@ -120,6 +117,7 @@ static void pnp_release_device(struct device *dmdev)
 int __pnp_add_device(struct pnp_dev *dev)
 {
         int ret;
+
         pnp_fixup_device(dev);
         dev->dev.bus = &pnp_bus_type;
         dev->dev.dma_mask = &dev->dma_mask;
@@ -143,13 +141,13 @@ int __pnp_add_device(struct pnp_dev *dev)
  *
  *  adds to driver model, name database, fixups, interface, etc.
  */
-
 int pnp_add_device(struct pnp_dev *dev)
 {
         if (!dev || !dev->protocol || dev->card)
                 return -EINVAL;
         dev->dev.parent = &dev->protocol->dev;
-        sprintf(dev->dev.bus_id, "%02x:%02x", dev->protocol->number, dev->number);
+        sprintf(dev->dev.bus_id, "%02x:%02x", dev->protocol->number,
+                dev->number);
         return __pnp_add_device(dev);
 }
 
@@ -162,21 +160,6 @@ void __pnp_remove_device(struct pnp_dev *dev)
         device_unregister(&dev->dev);
 }
 
-/**
- * pnp_remove_device - removes a pnp device from the pnp layer
- * @dev: pointer to dev to add
- *
- * this function will free all mem used by dev
- */
-#if 0
-void pnp_remove_device(struct pnp_dev *dev)
-{
-        if (!dev || dev->card)
-                return;
-        __pnp_remove_device(dev);
-}
-#endif  /*  0  */
-
 static int __init pnp_init(void)
 {
         printk(KERN_INFO "Linux Plug and Play Support v0.97 (c) Adam Belay\n");
@@ -184,10 +167,3 @@ static int __init pnp_init(void)
 }
 
 subsys_initcall(pnp_init);
-
-#if 0
-EXPORT_SYMBOL(pnp_register_protocol);
-EXPORT_SYMBOL(pnp_unregister_protocol);
-EXPORT_SYMBOL(pnp_add_device);
-EXPORT_SYMBOL(pnp_remove_device);
-#endif  /*  0  */
diff --git a/drivers/pnp/driver.c b/drivers/pnp/driver.c
index 1432806451cd..30b8f6f3258a 100644
--- a/drivers/pnp/driver.c
+++ b/drivers/pnp/driver.c
@@ -2,7 +2,6 @@
  * driver.c - device id matching, driver model, etc.
  *
  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/string.h>
@@ -16,12 +15,11 @@
 static int compare_func(const char *ida, const char *idb)
 {
         int i;
+
         /* we only need to compare the last 4 chars */
-        for (i=3; i<7; i++)
-        {
+        for (i = 3; i < 7; i++) {
                 if (ida[i] != 'X' &&
-                    idb[i] != 'X' &&
-                    toupper(ida[i]) != toupper(idb[i]))
+                    idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
                         return 0;
         }
         return 1;
@@ -31,20 +29,22 @@ int compare_pnp_id(struct pnp_id *pos, const char *id)
 {
         if (!pos || !id || (strlen(id) != 7))
                 return 0;
-        if (memcmp(id,"ANYDEVS",7)==0)
+        if (memcmp(id, "ANYDEVS", 7) == 0)
                 return 1;
-        while (pos){
-                if (memcmp(pos->id,id,3)==0)
-                        if (compare_func(pos->id,id)==1)
+        while (pos) {
+                if (memcmp(pos->id, id, 3) == 0)
+                        if (compare_func(pos->id, id) == 1)
                                 return 1;
                 pos = pos->next;
         }
         return 0;
 }
 
-static const struct pnp_device_id * match_device(struct pnp_driver *drv, struct pnp_dev *dev)
+static const struct pnp_device_id *match_device(struct pnp_driver *drv,
+                                                struct pnp_dev *dev)
 {
         const struct pnp_device_id *drv_id = drv->id_table;
+
         if (!drv_id)
                 return NULL;
 
@@ -59,7 +59,7 @@ static const struct pnp_device_id * match_device(struct pnp_driver *drv, struct
 int pnp_device_attach(struct pnp_dev *pnp_dev)
 {
         spin_lock(&pnp_lock);
-        if(pnp_dev->status != PNP_READY){
+        if (pnp_dev->status != PNP_READY) {
                 spin_unlock(&pnp_lock);
                 return -EBUSY;
         }
@@ -86,7 +86,8 @@ static int pnp_device_probe(struct device *dev)
         pnp_dev = to_pnp_dev(dev);
         pnp_drv = to_pnp_driver(dev->driver);
 
-        pnp_dbg("match found with the PnP device '%s' and the driver '%s'", dev->bus_id,pnp_drv->name);
+        pnp_dbg("match found with the PnP device '%s' and the driver '%s'",
+                dev->bus_id, pnp_drv->name);
 
         error = pnp_device_attach(pnp_dev);
         if (error < 0)
@@ -99,7 +100,7 @@ static int pnp_device_probe(struct device *dev)
                                 return error;
                 }
         } else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
-                    == PNP_DRIVER_RES_DISABLE) {
+                   == PNP_DRIVER_RES_DISABLE) {
                 error = pnp_disable_dev(pnp_dev);
                 if (error < 0)
                         return error;
@@ -110,22 +111,22 @@ static int pnp_device_probe(struct device *dev)
                 if (dev_id != NULL)
                         error = pnp_drv->probe(pnp_dev, dev_id);
         }
-        if (error >= 0){
+        if (error >= 0) {
                 pnp_dev->driver = pnp_drv;
                 error = 0;
         } else
                 goto fail;
         return error;
 
-fail:
+      fail:
         pnp_device_detach(pnp_dev);
         return error;
 }
 
 static int pnp_device_remove(struct device *dev)
 {
-        struct pnp_dev * pnp_dev = to_pnp_dev(dev);
-        struct pnp_driver * drv = pnp_dev->driver;
+        struct pnp_dev *pnp_dev = to_pnp_dev(dev);
+        struct pnp_driver *drv = pnp_dev->driver;
 
         if (drv) {
                 if (drv->remove)
@@ -138,8 +139,9 @@ static int pnp_device_remove(struct device *dev)
 
 static int pnp_bus_match(struct device *dev, struct device_driver *drv)
 {
-        struct pnp_dev * pnp_dev = to_pnp_dev(dev);
-        struct pnp_driver * pnp_drv = to_pnp_driver(drv);
+        struct pnp_dev *pnp_dev = to_pnp_dev(dev);
+        struct pnp_driver *pnp_drv = to_pnp_driver(drv);
+
         if (match_device(pnp_drv, pnp_dev) == NULL)
                 return 0;
         return 1;
@@ -147,8 +149,8 @@ static int pnp_bus_match(struct device *dev, struct device_driver *drv)
 
 static int pnp_bus_suspend(struct device *dev, pm_message_t state)
 {
-        struct pnp_dev * pnp_dev = to_pnp_dev(dev);
-        struct pnp_driver * pnp_drv = pnp_dev->driver;
+        struct pnp_dev *pnp_dev = to_pnp_dev(dev);
+        struct pnp_driver *pnp_drv = pnp_dev->driver;
         int error;
 
         if (!pnp_drv)
@@ -162,9 +164,9 @@ static int pnp_bus_suspend(struct device *dev, pm_message_t state)
 
         if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE) &&
             pnp_can_disable(pnp_dev)) {
-                error = pnp_stop_dev(pnp_dev);
-                if (error)
-                        return error;
+                error = pnp_stop_dev(pnp_dev);
+                if (error)
+                        return error;
         }
 
         if (pnp_dev->protocol && pnp_dev->protocol->suspend)
@@ -174,8 +176,8 @@ static int pnp_bus_suspend(struct device *dev, pm_message_t state)
 
 static int pnp_bus_resume(struct device *dev)
 {
-        struct pnp_dev * pnp_dev = to_pnp_dev(dev);
-        struct pnp_driver * pnp_drv = pnp_dev->driver;
+        struct pnp_dev *pnp_dev = to_pnp_dev(dev);
+        struct pnp_driver *pnp_drv = pnp_dev->driver;
         int error;
 
         if (!pnp_drv)
@@ -197,12 +199,12 @@ static int pnp_bus_resume(struct device *dev)
 }
 
 struct bus_type pnp_bus_type = {
-        .name   = "pnp",
-        .match  = pnp_bus_match,
-        .probe  = pnp_device_probe,
-        .remove = pnp_device_remove,
+        .name    = "pnp",
+        .match   = pnp_bus_match,
+        .probe   = pnp_device_probe,
+        .remove  = pnp_device_remove,
         .suspend = pnp_bus_suspend,
-        .resume = pnp_bus_resume,
+        .resume  = pnp_bus_resume,
 };
 
 int pnp_register_driver(struct pnp_driver *drv)
@@ -225,12 +227,11 @@ void pnp_unregister_driver(struct pnp_driver *drv)
  * pnp_add_id - adds an EISA id to the specified device
  * @id: pointer to a pnp_id structure
  * @dev: pointer to the desired device
- *
  */
-
 int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev)
 {
         struct pnp_id *ptr;
+
         if (!id)
                 return -EINVAL;
         if (!dev)
@@ -248,8 +249,5 @@ int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev)
 
 EXPORT_SYMBOL(pnp_register_driver);
 EXPORT_SYMBOL(pnp_unregister_driver);
-#if 0
-EXPORT_SYMBOL(pnp_add_id);
-#endif
 EXPORT_SYMBOL(pnp_device_attach);
 EXPORT_SYMBOL(pnp_device_detach);
diff --git a/drivers/pnp/interface.c b/drivers/pnp/interface.c
index ac9fcd499f3f..fe6684e13e82 100644
--- a/drivers/pnp/interface.c
+++ b/drivers/pnp/interface.c
@@ -3,7 +3,6 @@
  *
  * Some code, especially possible resource dumping is based on isapnp_proc.c (c) Jaroslav Kysela <perex@suse.cz>
  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/pnp.h>
@@ -29,7 +28,7 @@ struct pnp_info_buffer {
 
 typedef struct pnp_info_buffer pnp_info_buffer_t;
 
-static int pnp_printf(pnp_info_buffer_t * buffer, char *fmt,...)
+static int pnp_printf(pnp_info_buffer_t * buffer, char *fmt, ...)
 {
         va_list args;
         int res;
@@ -48,14 +47,18 @@ static int pnp_printf(pnp_info_buffer_t * buffer, char *fmt,...)
         return res;
 }
 
-static void pnp_print_port(pnp_info_buffer_t *buffer, char *space, struct pnp_port *port)
+static void pnp_print_port(pnp_info_buffer_t * buffer, char *space,
+                           struct pnp_port *port)
 {
-        pnp_printf(buffer, "%sport 0x%x-0x%x, align 0x%x, size 0x%x, %i-bit address decoding\n",
-                        space, port->min, port->max, port->align ? (port->align-1) : 0, port->size,
-                        port->flags & PNP_PORT_FLAG_16BITADDR ? 16 : 10);
+        pnp_printf(buffer,
+                   "%sport 0x%x-0x%x, align 0x%x, size 0x%x, %i-bit address decoding\n",
+                   space, port->min, port->max,
+                   port->align ? (port->align - 1) : 0, port->size,
+                   port->flags & PNP_PORT_FLAG_16BITADDR ? 16 : 10);
 }
 
-static void pnp_print_irq(pnp_info_buffer_t *buffer, char *space, struct pnp_irq *irq)
+static void pnp_print_irq(pnp_info_buffer_t * buffer, char *space,
+                          struct pnp_irq *irq)
 {
         int first = 1, i;
 
@@ -85,14 +88,15 @@ static void pnp_print_irq(pnp_info_buffer_t *buffer, char *space, struct pnp_irq
         pnp_printf(buffer, "\n");
 }
 
-static void pnp_print_dma(pnp_info_buffer_t *buffer, char *space, struct pnp_dma *dma)
+static void pnp_print_dma(pnp_info_buffer_t * buffer, char *space,
+                          struct pnp_dma *dma)
 {
         int first = 1, i;
         char *s;
 
         pnp_printf(buffer, "%sdma ", space);
         for (i = 0; i < 8; i++)
-                if (dma->map & (1<<i)) {
+                if (dma->map & (1 << i)) {
                         if (!first) {
                                 pnp_printf(buffer, ",");
                         } else {
@@ -136,12 +140,13 @@ static void pnp_print_dma(pnp_info_buffer_t *buffer, char *space, struct pnp_dma
         pnp_printf(buffer, " %s\n", s);
 }
 
-static void pnp_print_mem(pnp_info_buffer_t *buffer, char *space, struct pnp_mem *mem)
+static void pnp_print_mem(pnp_info_buffer_t * buffer, char *space,
+                          struct pnp_mem *mem)
 {
         char *s;
 
         pnp_printf(buffer, "%sMemory 0x%x-0x%x, align 0x%x, size 0x%x",
-                        space, mem->min, mem->max, mem->align, mem->size);
+                   space, mem->min, mem->max, mem->align, mem->size);
         if (mem->flags & IORESOURCE_MEM_WRITEABLE)
                 pnp_printf(buffer, ", writeable");
         if (mem->flags & IORESOURCE_MEM_CACHEABLE)
@@ -168,7 +173,7 @@ static void pnp_print_mem(pnp_info_buffer_t *buffer, char *space, struct pnp_mem
         pnp_printf(buffer, ", %s\n", s);
 }
 
-static void pnp_print_option(pnp_info_buffer_t *buffer, char *space,
+static void pnp_print_option(pnp_info_buffer_t * buffer, char *space,
                              struct pnp_option *option, int dep)
 {
         char *s;
@@ -179,19 +184,19 @@ static void pnp_print_option(pnp_info_buffer_t *buffer, char *space,
 
         if (dep) {
                 switch (option->priority) {
-                        case PNP_RES_PRIORITY_PREFERRED:
+                case PNP_RES_PRIORITY_PREFERRED:
                         s = "preferred";
                         break;
-                        case PNP_RES_PRIORITY_ACCEPTABLE:
+                case PNP_RES_PRIORITY_ACCEPTABLE:
                         s = "acceptable";
                         break;
-                        case PNP_RES_PRIORITY_FUNCTIONAL:
+                case PNP_RES_PRIORITY_FUNCTIONAL:
                         s = "functional";
                         break;
-                        default:
+                default:
                         s = "invalid";
                 }
-                pnp_printf(buffer, "Dependent: %02i - Priority %s\n",dep, s);
+                pnp_printf(buffer, "Dependent: %02i - Priority %s\n", dep, s);
         }
 
         for (port = option->port; port; port = port->next)
@@ -204,16 +209,16 @@ static void pnp_print_option(pnp_info_buffer_t *buffer, char *space,
                 pnp_print_mem(buffer, space, mem);
 }
 
-
-static ssize_t pnp_show_options(struct device *dmdev, struct device_attribute *attr, char *buf)
+static ssize_t pnp_show_options(struct device *dmdev,
+                                struct device_attribute *attr, char *buf)
 {
         struct pnp_dev *dev = to_pnp_dev(dmdev);
-        struct pnp_option * independent = dev->independent;
-        struct pnp_option * dependent = dev->dependent;
+        struct pnp_option *independent = dev->independent;
+        struct pnp_option *dependent = dev->dependent;
         int ret, dep = 1;
 
         pnp_info_buffer_t *buffer = (pnp_info_buffer_t *)
-                                 pnp_alloc(sizeof(pnp_info_buffer_t));
+            pnp_alloc(sizeof(pnp_info_buffer_t));
         if (!buffer)
                 return -ENOMEM;
 
@@ -223,7 +228,7 @@ static ssize_t pnp_show_options(struct device *dmdev, struct device_attribute *a
         if (independent)
                 pnp_print_option(buffer, "", independent, 0);
 
-        while (dependent){
+        while (dependent) {
                 pnp_print_option(buffer, "   ", dependent, dep);
                 dependent = dependent->next;
                 dep++;
@@ -233,10 +238,11 @@ static ssize_t pnp_show_options(struct device *dmdev, struct device_attribute *a
         return ret;
 }
 
-static DEVICE_ATTR(options,S_IRUGO,pnp_show_options,NULL);
+static DEVICE_ATTR(options, S_IRUGO, pnp_show_options, NULL);
 
-
-static ssize_t pnp_show_current_resources(struct device *dmdev, struct device_attribute *attr, char *buf)
+static ssize_t pnp_show_current_resources(struct device *dmdev,
+                                          struct device_attribute *attr,
+                                          char *buf)
 {
         struct pnp_dev *dev = to_pnp_dev(dmdev);
         int i, ret;
@@ -252,52 +258,56 @@ static ssize_t pnp_show_current_resources(struct device *dmdev, struct device_at
         buffer->buffer = buf;
         buffer->curr = buffer->buffer;
 
-        pnp_printf(buffer,"state = ");
+        pnp_printf(buffer, "state = ");
         if (dev->active)
-                pnp_printf(buffer,"active\n");
+                pnp_printf(buffer, "active\n");
         else
-                pnp_printf(buffer,"disabled\n");
+                pnp_printf(buffer, "disabled\n");
 
         for (i = 0; i < PNP_MAX_PORT; i++) {
                 if (pnp_port_valid(dev, i)) {
-                        pnp_printf(buffer,"io");
+                        pnp_printf(buffer, "io");
                         if (pnp_port_flags(dev, i) & IORESOURCE_DISABLED)
-                                pnp_printf(buffer," disabled\n");
+                                pnp_printf(buffer, " disabled\n");
                         else
-                                pnp_printf(buffer," 0x%llx-0x%llx\n",
-                                        (unsigned long long)pnp_port_start(dev, i),
-                                        (unsigned long long)pnp_port_end(dev, i));
+                                pnp_printf(buffer, " 0x%llx-0x%llx\n",
+                                           (unsigned long long)
+                                           pnp_port_start(dev, i),
+                                           (unsigned long long)pnp_port_end(dev,
+                                                                            i));
                 }
         }
         for (i = 0; i < PNP_MAX_MEM; i++) {
                 if (pnp_mem_valid(dev, i)) {
-                        pnp_printf(buffer,"mem");
+                        pnp_printf(buffer, "mem");
                         if (pnp_mem_flags(dev, i) & IORESOURCE_DISABLED)
-                                pnp_printf(buffer," disabled\n");
+                                pnp_printf(buffer, " disabled\n");
                         else
-                                pnp_printf(buffer," 0x%llx-0x%llx\n",
-                                        (unsigned long long)pnp_mem_start(dev, i),
-                                        (unsigned long long)pnp_mem_end(dev, i));
+                                pnp_printf(buffer, " 0x%llx-0x%llx\n",
+                                           (unsigned long long)
+                                           pnp_mem_start(dev, i),
+                                           (unsigned long long)pnp_mem_end(dev,
+                                                                           i));
                 }
         }
         for (i = 0; i < PNP_MAX_IRQ; i++) {
                 if (pnp_irq_valid(dev, i)) {
-                        pnp_printf(buffer,"irq");
+                        pnp_printf(buffer, "irq");
                         if (pnp_irq_flags(dev, i) & IORESOURCE_DISABLED)
-                                pnp_printf(buffer," disabled\n");
+                                pnp_printf(buffer, " disabled\n");
                         else
-                                pnp_printf(buffer," %lld\n",
-                                        (unsigned long long)pnp_irq(dev, i));
+                                pnp_printf(buffer, " %lld\n",
+                                           (unsigned long long)pnp_irq(dev, i));
                 }
         }
         for (i = 0; i < PNP_MAX_DMA; i++) {
                 if (pnp_dma_valid(dev, i)) {
-                        pnp_printf(buffer,"dma");
+                        pnp_printf(buffer, "dma");
                         if (pnp_dma_flags(dev, i) & IORESOURCE_DISABLED)
-                                pnp_printf(buffer," disabled\n");
+                                pnp_printf(buffer, " disabled\n");
                         else
-                                pnp_printf(buffer," %lld\n",
-                                        (unsigned long long)pnp_dma(dev, i));
+                                pnp_printf(buffer, " %lld\n",
+                                           (unsigned long long)pnp_dma(dev, i));
                 }
         }
         ret = (buffer->curr - buf);
@@ -308,55 +318,57 @@ static ssize_t pnp_show_current_resources(struct device *dmdev, struct device_at
 extern struct semaphore pnp_res_mutex;
 
 static ssize_t
-pnp_set_current_resources(struct device * dmdev, struct device_attribute *attr, const char * ubuf, size_t count)
+pnp_set_current_resources(struct device *dmdev, struct device_attribute *attr,
+                          const char *ubuf, size_t count)
 {
         struct pnp_dev *dev = to_pnp_dev(dmdev);
-        char    *buf = (void *)ubuf;
-        int     retval = 0;
+        char *buf = (void *)ubuf;
+        int retval = 0;
 
         if (dev->status & PNP_ATTACHED) {
                 retval = -EBUSY;
-                pnp_info("Device %s cannot be configured because it is in use.", dev->dev.bus_id);
+                pnp_info("Device %s cannot be configured because it is in use.",
+                         dev->dev.bus_id);
                 goto done;
         }
 
         while (isspace(*buf))
                 ++buf;
-        if (!strnicmp(buf,"disable",7)) {
+        if (!strnicmp(buf, "disable", 7)) {
                 retval = pnp_disable_dev(dev);
                 goto done;
         }
-        if (!strnicmp(buf,"activate",8)) {
+        if (!strnicmp(buf, "activate", 8)) {
                 retval = pnp_activate_dev(dev);
                 goto done;
         }
-        if (!strnicmp(buf,"fill",4)) {
+        if (!strnicmp(buf, "fill", 4)) {
                 if (dev->active)
                         goto done;
                 retval = pnp_auto_config_dev(dev);
                 goto done;
         }
-        if (!strnicmp(buf,"auto",4)) {
+        if (!strnicmp(buf, "auto", 4)) {
                 if (dev->active)
                         goto done;
                 pnp_init_resource_table(&dev->res);
                 retval = pnp_auto_config_dev(dev);
                 goto done;
         }
-        if (!strnicmp(buf,"clear",5)) {
+        if (!strnicmp(buf, "clear", 5)) {
                 if (dev->active)
                         goto done;
                 pnp_init_resource_table(&dev->res);
                 goto done;
         }
-        if (!strnicmp(buf,"get",3)) {
+        if (!strnicmp(buf, "get", 3)) {
                 down(&pnp_res_mutex);
                 if (pnp_can_read(dev))
                         dev->protocol->get(dev, &dev->res);
                 up(&pnp_res_mutex);
                 goto done;
         }
-        if (!strnicmp(buf,"set",3)) {
+        if (!strnicmp(buf, "set", 3)) {
                 int nport = 0, nmem = 0, nirq = 0, ndma = 0;
                 if (dev->active)
                         goto done;
@@ -366,65 +378,77 @@ pnp_set_current_resources(struct device * dmdev, struct device_attribute *attr,
                 while (1) {
                         while (isspace(*buf))
                                 ++buf;
-                        if (!strnicmp(buf,"io",2)) {
+                        if (!strnicmp(buf, "io", 2)) {
                                 buf += 2;
                                 while (isspace(*buf))
                                         ++buf;
-                                dev->res.port_resource[nport].start = simple_strtoul(buf,&buf,0);
+                                dev->res.port_resource[nport].start =
+                                    simple_strtoul(buf, &buf, 0);
                                 while (isspace(*buf))
                                         ++buf;
-                                if(*buf == '-') {
+                                if (*buf == '-') {
                                         buf += 1;
                                         while (isspace(*buf))
                                                 ++buf;
-                                        dev->res.port_resource[nport].end = simple_strtoul(buf,&buf,0);
+                                        dev->res.port_resource[nport].end =
+                                            simple_strtoul(buf, &buf, 0);
                                 } else
-                                        dev->res.port_resource[nport].end = dev->res.port_resource[nport].start;
-                                dev->res.port_resource[nport].flags = IORESOURCE_IO;
+                                        dev->res.port_resource[nport].end =
+                                            dev->res.port_resource[nport].start;
+                                dev->res.port_resource[nport].flags =
+                                    IORESOURCE_IO;
                                 nport++;
                                 if (nport >= PNP_MAX_PORT)
                                         break;
                                 continue;
                         }
-                        if (!strnicmp(buf,"mem",3)) {
+                        if (!strnicmp(buf, "mem", 3)) {
                                 buf += 3;
                                 while (isspace(*buf))
                                         ++buf;
-                                dev->res.mem_resource[nmem].start = simple_strtoul(buf,&buf,0);
+                                dev->res.mem_resource[nmem].start =
+                                    simple_strtoul(buf, &buf, 0);
                                 while (isspace(*buf))
                                         ++buf;
-                                if(*buf == '-') {
+                                if (*buf == '-') {
                                         buf += 1;
                                         while (isspace(*buf))
                                                 ++buf;
-                                        dev->res.mem_resource[nmem].end = simple_strtoul(buf,&buf,0);
+                                        dev->res.mem_resource[nmem].end =
+                                            simple_strtoul(buf, &buf, 0);
                                 } else
-                                        dev->res.mem_resource[nmem].end = dev->res.mem_resource[nmem].start;
-                                dev->res.mem_resource[nmem].flags = IORESOURCE_MEM;
+                                        dev->res.mem_resource[nmem].end =
+                                            dev->res.mem_resource[nmem].start;
+                                dev->res.mem_resource[nmem].flags =
+                                    IORESOURCE_MEM;
                                 nmem++;
                                 if (nmem >= PNP_MAX_MEM)
                                         break;
                                 continue;
                         }
-                        if (!strnicmp(buf,"irq",3)) {
+                        if (!strnicmp(buf, "irq", 3)) {
                                 buf += 3;
                                 while (isspace(*buf))
                                         ++buf;
                                 dev->res.irq_resource[nirq].start =
-                                dev->res.irq_resource[nirq].end = simple_strtoul(buf,&buf,0);
-                                dev->res.irq_resource[nirq].flags = IORESOURCE_IRQ;
+                                    dev->res.irq_resource[nirq].end =
+                                    simple_strtoul(buf, &buf, 0);
+                                dev->res.irq_resource[nirq].flags =
+                                    IORESOURCE_IRQ;
                                 nirq++;
                                 if (nirq >= PNP_MAX_IRQ)
                                         break;
                                 continue;
                         }
-                        if (!strnicmp(buf,"dma",3)) {
+                        if (!strnicmp(buf, "dma", 3)) {
                                 buf += 3;
                                 while (isspace(*buf))
                                         ++buf;
                                 dev->res.dma_resource[ndma].start =
-                                dev->res.dma_resource[ndma].end = simple_strtoul(buf,&buf,0);
-                                dev->res.dma_resource[ndma].flags = IORESOURCE_DMA;
+                                    dev->res.dma_resource[ndma].end =
+                                    simple_strtoul(buf, &buf, 0);
+                                dev->res.dma_resource[ndma].flags =
+                                    IORESOURCE_DMA;
                                 ndma++;
                                 if (ndma >= PNP_MAX_DMA)
                                         break;
@@ -435,45 +459,50 @@ pnp_set_current_resources(struct device * dmdev, struct device_attribute *attr,
                 up(&pnp_res_mutex);
                 goto done;
         }
- done:
+      done:
         if (retval < 0)
                 return retval;
         return count;
 }
 
-static DEVICE_ATTR(resources,S_IRUGO | S_IWUSR,
-                   pnp_show_current_resources,pnp_set_current_resources);
+static DEVICE_ATTR(resources, S_IRUGO | S_IWUSR,
+                   pnp_show_current_resources, pnp_set_current_resources);
 
-static ssize_t pnp_show_current_ids(struct device *dmdev, struct device_attribute *attr, char *buf)
+static ssize_t pnp_show_current_ids(struct device *dmdev,
+                                    struct device_attribute *attr, char *buf)
 {
         char *str = buf;
         struct pnp_dev *dev = to_pnp_dev(dmdev);
-        struct pnp_id * pos = dev->id;
+        struct pnp_id *pos = dev->id;
 
         while (pos) {
-                str += sprintf(str,"%s\n", pos->id);
+                str += sprintf(str, "%s\n", pos->id);
                 pos = pos->next;
         }
         return (str - buf);
 }
 
-static DEVICE_ATTR(id,S_IRUGO,pnp_show_current_ids,NULL);
+static DEVICE_ATTR(id, S_IRUGO, pnp_show_current_ids, NULL);
 
 int pnp_interface_attach_device(struct pnp_dev *dev)
 {
-        int rc = device_create_file(&dev->dev,&dev_attr_options);
-        if (rc) goto err;
-        rc = device_create_file(&dev->dev,&dev_attr_resources);
-        if (rc) goto err_opt;
-        rc = device_create_file(&dev->dev,&dev_attr_id);
-        if (rc) goto err_res;
+        int rc = device_create_file(&dev->dev, &dev_attr_options);
+
+        if (rc)
+                goto err;
+        rc = device_create_file(&dev->dev, &dev_attr_resources);
+        if (rc)
+                goto err_opt;
+        rc = device_create_file(&dev->dev, &dev_attr_id);
+        if (rc)
+                goto err_res;
 
         return 0;
 
-err_res:
-        device_remove_file(&dev->dev,&dev_attr_resources);
-err_opt:
-        device_remove_file(&dev->dev,&dev_attr_options);
-err:
+      err_res:
+        device_remove_file(&dev->dev, &dev_attr_resources);
+      err_opt:
+        device_remove_file(&dev->dev, &dev_attr_options);
+      err:
         return rc;
 }
diff --git a/drivers/pnp/isapnp/compat.c b/drivers/pnp/isapnp/compat.c
index 0697ab88a9ac..10bdcc4d4f7b 100644
--- a/drivers/pnp/isapnp/compat.c
+++ b/drivers/pnp/isapnp/compat.c
@@ -3,34 +3,30 @@
  *            the old isapnp APIs. If possible use the new APIs instead.
  *
  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
- *
  */
- 
-/* TODO: see if more isapnp functions are needed here */
 
 #include <linux/module.h>
 #include <linux/isapnp.h>
 #include <linux/string.h>
 
-static void pnp_convert_id(char *buf, unsigned short vendor, unsigned short device)
+static void pnp_convert_id(char *buf, unsigned short vendor,
+                           unsigned short device)
 {
         sprintf(buf, "%c%c%c%x%x%x%x",
-                        'A' + ((vendor >> 2) & 0x3f) - 1,
-                        'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
-                        'A' + ((vendor >> 8) & 0x1f) - 1,
-                        (device >> 4) & 0x0f,
-                        device & 0x0f,
-                        (device >> 12) & 0x0f,
-                        (device >> 8) & 0x0f);
+                'A' + ((vendor >> 2) & 0x3f) - 1,
+                'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
+                'A' + ((vendor >> 8) & 0x1f) - 1,
+                (device >> 4) & 0x0f, device & 0x0f,
+                (device >> 12) & 0x0f, (device >> 8) & 0x0f);
 }
 
-struct pnp_card *pnp_find_card(unsigned short vendor,
-                               unsigned short device,
+struct pnp_card *pnp_find_card(unsigned short vendor, unsigned short device,
                                struct pnp_card *from)
 {
         char id[8];
         char any[8];
         struct list_head *list;
+
         pnp_convert_id(id, vendor, device);
         pnp_convert_id(any, ISAPNP_ANY_ID, ISAPNP_ANY_ID);
 
@@ -38,20 +34,20 @@ struct pnp_card *pnp_find_card(unsigned short vendor,
 
         while (list != &pnp_cards) {
                 struct pnp_card *card = global_to_pnp_card(list);
-                if (compare_pnp_id(card->id,id) || (memcmp(id,any,7)==0))
+
+                if (compare_pnp_id(card->id, id) || (memcmp(id, any, 7) == 0))
                         return card;
                 list = list->next;
         }
         return NULL;
 }
 
-struct pnp_dev *pnp_find_dev(struct pnp_card *card,
-                             unsigned short vendor,
-                             unsigned short function,
-                             struct pnp_dev *from)
+struct pnp_dev *pnp_find_dev(struct pnp_card *card, unsigned short vendor,
+                             unsigned short function, struct pnp_dev *from)
 {
         char id[8];
         char any[8];
+
         pnp_convert_id(id, vendor, function);
         pnp_convert_id(any, ISAPNP_ANY_ID, ISAPNP_ANY_ID);
         if (card == NULL) {     /* look for a logical device from all cards */
@@ -63,7 +59,9 @@ struct pnp_dev *pnp_find_dev(struct pnp_card *card,
 
                 while (list != &pnp_global) {
                         struct pnp_dev *dev = global_to_pnp_dev(list);
-                        if (compare_pnp_id(dev->id,id) || (memcmp(id,any,7)==0))
+
+                        if (compare_pnp_id(dev->id, id) ||
+                            (memcmp(id, any, 7) == 0))
                                 return dev;
                         list = list->next;
                 }
@@ -78,7 +76,8 @@ struct pnp_dev *pnp_find_dev(struct pnp_card *card,
                 }
                 while (list != &card->devices) {
                         struct pnp_dev *dev = card_to_pnp_dev(list);
-                        if (compare_pnp_id(dev->id,id))
+
+                        if (compare_pnp_id(dev->id, id))
                                 return dev;
                         list = list->next;
                 }
diff --git a/drivers/pnp/isapnp/core.c b/drivers/pnp/isapnp/core.c
index 914d00c423ad..b4e2aa995b53 100644
--- a/drivers/pnp/isapnp/core.c
+++ b/drivers/pnp/isapnp/core.c
@@ -51,10 +51,10 @@
 #define ISAPNP_DEBUG
 #endif
 
-int isapnp_disable;                     /* Disable ISA PnP */
-static int isapnp_rdp;                  /* Read Data Port */
-static int isapnp_reset = 1;            /* reset all PnP cards (deactivate) */
-static int isapnp_verbose = 1;          /* verbose mode */
+int isapnp_disable;             /* Disable ISA PnP */
+static int isapnp_rdp;          /* Read Data Port */
+static int isapnp_reset = 1;    /* reset all PnP cards (deactivate) */
+static int isapnp_verbose = 1;  /* verbose mode */
 
 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
 MODULE_DESCRIPTION("Generic ISA Plug & Play support");
@@ -126,7 +126,7 @@ static unsigned short isapnp_read_word(unsigned char idx)
         unsigned short val;
 
         val = isapnp_read_byte(idx);
-        val = (val << 8) + isapnp_read_byte(idx+1);
+        val = (val << 8) + isapnp_read_byte(idx + 1);
         return val;
 }
 
@@ -139,7 +139,7 @@ void isapnp_write_byte(unsigned char idx, unsigned char val)
 static void isapnp_write_word(unsigned char idx, unsigned short val)
 {
         isapnp_write_byte(idx, val >> 8);
-        isapnp_write_byte(idx+1, val);
+        isapnp_write_byte(idx + 1, val);
 }
 
 static void isapnp_key(void)
@@ -193,7 +193,7 @@ static void isapnp_deactivate(unsigned char logdev)
 static void __init isapnp_peek(unsigned char *data, int bytes)
 {
         int i, j;
-        unsigned char d=0;
+        unsigned char d = 0;
 
         for (i = 1; i <= bytes; i++) {
                 for (j = 0; j < 20; j++) {
@@ -220,19 +220,18 @@ static int isapnp_next_rdp(void)
 {
         int rdp = isapnp_rdp;
         static int old_rdp = 0;
-        
-        if(old_rdp)
-        {
+
+        if (old_rdp) {
                 release_region(old_rdp, 1);
                 old_rdp = 0;
         }
         while (rdp <= 0x3ff) {
                 /*
-                 *      We cannot use NE2000 probe spaces for ISAPnP or we
-                 *      will lock up machines.
+                 *      We cannot use NE2000 probe spaces for ISAPnP or we
+                 *      will lock up machines.
                  */
-                if ((rdp < 0x280 || rdp >  0x380) && request_region(rdp, 1, "ISAPnP"))
-                {
+                if ((rdp < 0x280 || rdp > 0x380)
+                    && request_region(rdp, 1, "ISAPnP")) {
                         isapnp_rdp = rdp;
                         old_rdp = rdp;
                         return 0;
@@ -253,7 +252,6 @@ static inline void isapnp_set_rdp(void)
  *      Perform an isolation. The port selection code now tries to avoid
  *      "dangerous to read" ports.
  */
-
 static int __init isapnp_isolate_rdp_select(void)
 {
         isapnp_wait();
@@ -282,7 +280,6 @@ static int __init isapnp_isolate_rdp_select(void)
 /*
  *  Isolate (assign uniqued CSN) to all ISA PnP devices.
  */
-
 static int __init isapnp_isolate(void)
 {
         unsigned char checksum = 0x6a;
@@ -305,7 +302,9 @@ static int __init isapnp_isolate(void)
                         udelay(250);
                         if (data == 0x55aa)
                                 bit = 0x01;
-                        checksum = ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7) | (checksum >> 1);
+                        checksum =
+                            ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
+                            | (checksum >> 1);
                         bit = 0x00;
                 }
                 for (i = 65; i <= 72; i++) {
@@ -351,13 +350,12 @@ static int __init isapnp_isolate(void)
 /*
  *  Read one tag from stream.
  */
-
 static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
 {
         unsigned char tag, tmp[2];
 
         isapnp_peek(&tag, 1);
-        if (tag == 0)                           /* invalid tag */
+        if (tag == 0)           /* invalid tag */
                 return -1;
         if (tag & 0x80) {       /* large item */
                 *type = tag;
@@ -368,7 +366,8 @@ static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
                 *size = tag & 0x07;
         }
 #if 0
-        printk(KERN_DEBUG "tag = 0x%x, type = 0x%x, size = %i\n", tag, *type, *size);
+        printk(KERN_DEBUG "tag = 0x%x, type = 0x%x, size = %i\n", tag, *type,
+               *size);
 #endif
         if (*type == 0xff && *size == 0xffff)   /* probably invalid data */
                 return -1;
@@ -378,7 +377,6 @@ static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
 /*
  *  Skip specified number of bytes from stream.
  */
-
 static void __init isapnp_skip_bytes(int count)
 {
         isapnp_peek(NULL, count);
@@ -387,31 +385,30 @@ static void __init isapnp_skip_bytes(int count)
 /*
  *  Parse EISA id.
  */
-
-static void isapnp_parse_id(struct pnp_dev * dev, unsigned short vendor, unsigned short device)
+static void isapnp_parse_id(struct pnp_dev *dev, unsigned short vendor,
+                            unsigned short device)
 {
-        struct pnp_id * id;
+        struct pnp_id *id;
+
         if (!dev)
                 return;
         id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
         if (!id)
                 return;
         sprintf(id->id, "%c%c%c%x%x%x%x",
-                        'A' + ((vendor >> 2) & 0x3f) - 1,
-                        'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
-                        'A' + ((vendor >> 8) & 0x1f) - 1,
-                        (device >> 4) & 0x0f,
-                        device & 0x0f,
-                        (device >> 12) & 0x0f,
-                        (device >> 8) & 0x0f);
+                'A' + ((vendor >> 2) & 0x3f) - 1,
+                'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
+                'A' + ((vendor >> 8) & 0x1f) - 1,
+                (device >> 4) & 0x0f,
+                device & 0x0f, (device >> 12) & 0x0f, (device >> 8) & 0x0f);
         pnp_add_id(id, dev);
 }
 
 /*
  *  Parse logical device tag.
  */
-
-static struct pnp_dev * __init isapnp_parse_device(struct pnp_card *card, int size, int number)
+static struct pnp_dev *__init isapnp_parse_device(struct pnp_card *card,
+                                                  int size, int number)
 {
         unsigned char tmp[6];
         struct pnp_dev *dev;
@@ -435,13 +432,11 @@ static struct pnp_dev * __init isapnp_parse_device(struct pnp_card *card, int si
         return dev;
 }
 
-
 /*
  *  Add IRQ resource to resources list.
  */
-
 static void __init isapnp_parse_irq_resource(struct pnp_option *option,
-                                               int size)
+                                             int size)
 {
         unsigned char tmp[3];
         struct pnp_irq *irq;
@@ -458,15 +453,13 @@ static void __init isapnp_parse_irq_resource(struct pnp_option *option,
         else
                 irq->flags = IORESOURCE_IRQ_HIGHEDGE;
         pnp_register_irq_resource(option, irq);
-        return;
 }
 
 /*
  *  Add DMA resource to resources list.
  */
-
 static void __init isapnp_parse_dma_resource(struct pnp_option *option,
-                                               int size)
+                                             int size)
 {
         unsigned char tmp[2];
         struct pnp_dma *dma;
@@ -478,15 +471,13 @@ static void __init isapnp_parse_dma_resource(struct pnp_option *option,
         dma->map = tmp[0];
         dma->flags = tmp[1];
         pnp_register_dma_resource(option, dma);
-        return;
 }
 
 /*
  *  Add port resource to resources list.
  */
-
 static void __init isapnp_parse_port_resource(struct pnp_option *option,
-                                                int size)
+                                              int size)
 {
         unsigned char tmp[7];
         struct pnp_port *port;
@@ -500,16 +491,14 @@ static void __init isapnp_parse_port_resource(struct pnp_option *option,
         port->align = tmp[5];
         port->size = tmp[6];
         port->flags = tmp[0] ? PNP_PORT_FLAG_16BITADDR : 0;
-        pnp_register_port_resource(option,port);
-        return;
+        pnp_register_port_resource(option, port);
 }
 
 /*
  *  Add fixed port resource to resources list.
  */
-
 static void __init isapnp_parse_fixed_port_resource(struct pnp_option *option,
-                                                      int size)
+                                                    int size)
 {
         unsigned char tmp[3];
         struct pnp_port *port;
@@ -522,16 +511,14 @@ static void __init isapnp_parse_fixed_port_resource(struct pnp_option *option,
         port->size = tmp[2];
         port->align = 0;
         port->flags = PNP_PORT_FLAG_FIXED;
-        pnp_register_port_resource(option,port);
-        return;
+        pnp_register_port_resource(option, port);
 }
 
 /*
  *  Add memory resource to resources list.
  */
-
 static void __init isapnp_parse_mem_resource(struct pnp_option *option,
-                                               int size)
+                                             int size)
 {
         unsigned char tmp[9];
         struct pnp_mem *mem;
@@ -545,16 +532,14 @@ static void __init isapnp_parse_mem_resource(struct pnp_option *option,
         mem->align = (tmp[6] << 8) | tmp[5];
         mem->size = ((tmp[8] << 8) | tmp[7]) << 8;
         mem->flags = tmp[0];
-        pnp_register_mem_resource(option,mem);
-        return;
+        pnp_register_mem_resource(option, mem);
 }
 
 /*
  *  Add 32-bit memory resource to resources list.
  */
-
 static void __init isapnp_parse_mem32_resource(struct pnp_option *option,
-                                                 int size)
+                                               int size)
 {
         unsigned char tmp[17];
         struct pnp_mem *mem;
@@ -565,18 +550,19 @@ static void __init isapnp_parse_mem32_resource(struct pnp_option *option,
                 return;
         mem->min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
         mem->max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
-        mem->align = (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
-        mem->size = (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
+        mem->align =
+            (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
+        mem->size =
+            (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
         mem->flags = tmp[0];
-        pnp_register_mem_resource(option,mem);
+        pnp_register_mem_resource(option, mem);
 }
 
 /*
  *  Add 32-bit fixed memory resource to resources list.
  */
-
 static void __init isapnp_parse_fixed_mem32_resource(struct pnp_option *option,
-                                                       int size)
+                                                     int size)
 {
         unsigned char tmp[9];
         struct pnp_mem *mem;
@@ -585,28 +571,29 @@ static void __init isapnp_parse_fixed_mem32_resource(struct pnp_option *option,
         mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
         if (!mem)
                 return;
-        mem->min = mem->max = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
+        mem->min = mem->max =
+            (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
         mem->size = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
         mem->align = 0;
         mem->flags = tmp[0];
-        pnp_register_mem_resource(option,mem);
+        pnp_register_mem_resource(option, mem);
 }
 
 /*
  *  Parse card name for ISA PnP device.
- */ 
-
+ */
 static void __init
 isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
 {
         if (name[0] == '\0') {
-                unsigned short size1 = *size >= name_max ? (name_max - 1) : *size;
+                unsigned short size1 =
+                    *size >= name_max ? (name_max - 1) : *size;
                 isapnp_peek(name, size1);
                 name[size1] = '\0';
                 *size -= size1;
 
                 /* clean whitespace from end of string */
-                while (size1 > 0  &&  name[--size1] == ' ')
+                while (size1 > 0 && name[--size1] == ' ')
                         name[size1] = '\0';
         }
 }
@@ -614,7 +601,6 @@ isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
 /*
  *  Parse resource map for logical device.
  */
-
 static int __init isapnp_create_device(struct pnp_card *card,
                                        unsigned short size)
 {
@@ -622,6 +608,7 @@ static int __init isapnp_create_device(struct pnp_card *card,
         unsigned char type, tmp[17];
         struct pnp_option *option;
         struct pnp_dev *dev;
+
         if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
                 return 1;
         option = pnp_register_independent_option(dev);
@@ -629,17 +616,19 @@ static int __init isapnp_create_device(struct pnp_card *card,
                 kfree(dev);
                 return 1;
         }
-        pnp_add_card_device(card,dev);
+        pnp_add_card_device(card, dev);
 
         while (1) {
-                if (isapnp_read_tag(&type, &size)<0)
+                if (isapnp_read_tag(&type, &size) < 0)
                         return 1;
                 if (skip && type != _STAG_LOGDEVID && type != _STAG_END)
                         goto __skip;
                 switch (type) {
                 case _STAG_LOGDEVID:
                         if (size >= 5 && size <= 6) {
-                                if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
+                                if ((dev =
+                                     isapnp_parse_device(card, size,
+                                                         number++)) == NULL)
                                         return 1;
                                 size = 0;
                                 skip = 0;
@@ -648,7 +637,7 @@ static int __init isapnp_create_device(struct pnp_card *card,
                                         kfree(dev);
                                         return 1;
                                 }
-                                pnp_add_card_device(card,dev);
+                                pnp_add_card_device(card, dev);
                         } else {
                                 skip = 1;
                         }
@@ -658,7 +647,8 @@ static int __init isapnp_create_device(struct pnp_card *card,
                 case _STAG_COMPATDEVID:
                         if (size == 4 && compat < DEVICE_COUNT_COMPATIBLE) {
                                 isapnp_peek(tmp, 4);
-                                isapnp_parse_id(dev,(tmp[1] << 8) | tmp[0], (tmp[3] << 8) | tmp[2]);
+                                isapnp_parse_id(dev, (tmp[1] << 8) | tmp[0],
+                                                (tmp[3] << 8) | tmp[2]);
                                 compat++;
                                 size = 0;
                         }
@@ -684,7 +674,7 @@ static int __init isapnp_create_device(struct pnp_card *card,
                                 priority = 0x100 | tmp[0];
                                 size = 0;
                         }
-                        option = pnp_register_dependent_option(dev,priority);
+                        option = pnp_register_dependent_option(dev, priority);
                         if (!option)
                                 return 1;
                         break;
@@ -739,11 +729,13 @@ static int __init isapnp_create_device(struct pnp_card *card,
                                 isapnp_skip_bytes(size);
                         return 1;
                 default:
-                        printk(KERN_ERR "isapnp: unexpected or unknown tag type 0x%x for logical device %i (device %i), ignored\n", type, dev->number, card->number);
+                        printk(KERN_ERR
+                               "isapnp: unexpected or unknown tag type 0x%x for logical device %i (device %i), ignored\n",
+                               type, dev->number, card->number);
                 }
               __skip:
-                if (size > 0)
-                        isapnp_skip_bytes(size);
+                if (size > 0)
+                        isapnp_skip_bytes(size);
         }
         return 0;
 }
@@ -751,14 +743,13 @@ static int __init isapnp_create_device(struct pnp_card *card,
 /*
  *  Parse resource map for ISA PnP card.
  */
-
 static void __init isapnp_parse_resource_map(struct pnp_card *card)
 {
         unsigned char type, tmp[17];
         unsigned short size;
 
         while (1) {
-                if (isapnp_read_tag(&type, &size)<0)
+                if (isapnp_read_tag(&type, &size) < 0)
                         return;
                 switch (type) {
                 case _STAG_PNPVERNO:
@@ -771,7 +762,7 @@ static void __init isapnp_parse_resource_map(struct pnp_card *card)
                         break;
                 case _STAG_LOGDEVID:
                         if (size >= 5 && size <= 6) {
-                                if (isapnp_create_device(card, size)==1)
+                                if (isapnp_create_device(card, size) == 1)
                                         return;
                                 size = 0;
                         }
@@ -779,7 +770,8 @@ static void __init isapnp_parse_resource_map(struct pnp_card *card)
                 case _STAG_VENDOR:
                         break;
                 case _LTAG_ANSISTR:
-                        isapnp_parse_name(card->name, sizeof(card->name), &size);
+                        isapnp_parse_name(card->name, sizeof(card->name),
+                                          &size);
                         break;
                 case _LTAG_UNICODESTR:
                         /* silently ignore */
@@ -792,18 +784,19 @@ static void __init isapnp_parse_resource_map(struct pnp_card *card)
                                 isapnp_skip_bytes(size);
                         return;
                 default:
-                        printk(KERN_ERR "isapnp: unexpected or unknown tag type 0x%x for device %i, ignored\n", type, card->number);
+                        printk(KERN_ERR
+                               "isapnp: unexpected or unknown tag type 0x%x for device %i, ignored\n",
+                               type, card->number);
                 }
               __skip:
-                if (size > 0)
-                        isapnp_skip_bytes(size);
+                if (size > 0)
+                        isapnp_skip_bytes(size);
         }
 }
 
 /*
  *  Compute ISA PnP checksum for first eight bytes.
  */
-
 static unsigned char __init isapnp_checksum(unsigned char *data)
 {
         int i, j;
@@ -815,7 +808,9 @@ static unsigned char __init isapnp_checksum(unsigned char *data)
                         bit = 0;
                         if (b & (1 << j))
                                 bit = 1;
-                        checksum = ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7) | (checksum >> 1);
+                        checksum =
+                            ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
+                            | (checksum >> 1);
                 }
         }
         return checksum;
@@ -824,27 +819,25 @@ static unsigned char __init isapnp_checksum(unsigned char *data)
 /*
  *  Parse EISA id for ISA PnP card.
  */
-
-static void isapnp_parse_card_id(struct pnp_card * card, unsigned short vendor, unsigned short device)
+static void isapnp_parse_card_id(struct pnp_card *card, unsigned short vendor,
+                                 unsigned short device)
 {
-        struct pnp_id * id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
+        struct pnp_id *id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
+
         if (!id)
                 return;
         sprintf(id->id, "%c%c%c%x%x%x%x",
-                        'A' + ((vendor >> 2) & 0x3f) - 1,
-                        'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
-                        'A' + ((vendor >> 8) & 0x1f) - 1,
-                        (device >> 4) & 0x0f,
-                        device & 0x0f,
-                        (device >> 12) & 0x0f,
-                        (device >> 8) & 0x0f);
-        pnp_add_card_id(id,card);
+                'A' + ((vendor >> 2) & 0x3f) - 1,
+                'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
+                'A' + ((vendor >> 8) & 0x1f) - 1,
+                (device >> 4) & 0x0f,
+                device & 0x0f, (device >> 12) & 0x0f, (device >> 8) & 0x0f);
+        pnp_add_card_id(id, card);
 }
 
 /*
  *  Build device list for all present ISA PnP devices.
  */
-
 static int __init isapnp_build_device_list(void)
 {
         int csn;
@@ -858,22 +851,29 @@ static int __init isapnp_build_device_list(void)
                 isapnp_peek(header, 9);
                 checksum = isapnp_checksum(header);
 #if 0
-                printk(KERN_DEBUG "vendor: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
-                        header[0], header[1], header[2], header[3],
-                        header[4], header[5], header[6], header[7], header[8]);
+                printk(KERN_DEBUG
+                       "vendor: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
+                       header[0], header[1], header[2], header[3], header[4],
+                       header[5], header[6], header[7], header[8]);
                 printk(KERN_DEBUG "checksum = 0x%x\n", checksum);
 #endif
-                if ((card = kzalloc(sizeof(struct pnp_card), GFP_KERNEL)) == NULL)
+                if ((card =
+                     kzalloc(sizeof(struct pnp_card), GFP_KERNEL)) == NULL)
                         continue;
 
                 card->number = csn;
                 INIT_LIST_HEAD(&card->devices);
-                isapnp_parse_card_id(card, (header[1] << 8) | header[0], (header[3] << 8) | header[2]);
-                card->serial = (header[7] << 24) | (header[6] << 16) | (header[5] << 8) | header[4];
+                isapnp_parse_card_id(card, (header[1] << 8) | header[0],
+                                     (header[3] << 8) | header[2]);
+                card->serial =
+                    (header[7] << 24) | (header[6] << 16) | (header[5] << 8) |
+                    header[4];
                 isapnp_checksum_value = 0x00;
                 isapnp_parse_resource_map(card);
                 if (isapnp_checksum_value != 0x00)
-                        printk(KERN_ERR "isapnp: checksum for device %i is not valid (0x%x)\n", csn, isapnp_checksum_value);
+                        printk(KERN_ERR
+                               "isapnp: checksum for device %i is not valid (0x%x)\n",
+                               csn, isapnp_checksum_value);
                 card->checksum = isapnp_checksum_value;
                 card->protocol = &isapnp_protocol;
 
@@ -890,6 +890,7 @@ static int __init isapnp_build_device_list(void)
 int isapnp_present(void)
 {
         struct pnp_card *card;
+
         pnp_for_each_card(card) {
                 if (card->protocol == &isapnp_protocol)
                         return 1;
@@ -911,13 +912,13 @@ int isapnp_cfg_begin(int csn, int logdev)
         /* it is possible to set RDP only in the isolation phase */
         /*   Jens Thoms Toerring <Jens.Toerring@physik.fu-berlin.de> */
         isapnp_write_byte(0x02, 0x04);  /* clear CSN of card */
-        mdelay(2);                      /* is this necessary? */
-        isapnp_wake(csn);               /* bring card into sleep state */
-        isapnp_wake(0);                 /* bring card into isolation state */
-        isapnp_set_rdp();               /* reset the RDP port */
-        udelay(1000);                   /* delay 1000us */
+        mdelay(2);              /* is this necessary? */
+        isapnp_wake(csn);       /* bring card into sleep state */
+        isapnp_wake(0);         /* bring card into isolation state */
+        isapnp_set_rdp();       /* reset the RDP port */
+        udelay(1000);           /* delay 1000us */
         isapnp_write_byte(0x06, csn);   /* reset CSN to previous value */
-        udelay(250);                    /* is this necessary? */
+        udelay(250);            /* is this necessary? */
 #endif
         if (logdev >= 0)
                 isapnp_device(logdev);
@@ -931,12 +932,10 @@ int isapnp_cfg_end(void)
         return 0;
 }
 
-
 /*
- *  Inititialization.
+ *  Initialization.
  */
 
-
 EXPORT_SYMBOL(isapnp_protocol);
 EXPORT_SYMBOL(isapnp_present);
 EXPORT_SYMBOL(isapnp_cfg_begin);
@@ -946,7 +945,8 @@ EXPORT_SYMBOL(isapnp_read_byte);
 #endif
 EXPORT_SYMBOL(isapnp_write_byte);
 
-static int isapnp_read_resources(struct pnp_dev *dev, struct pnp_resource_table *res)
+static int isapnp_read_resources(struct pnp_dev *dev,
+                                 struct pnp_resource_table *res)
 {
         int tmp, ret;
 
@@ -960,31 +960,37 @@ static int isapnp_read_resources(struct pnp_dev *dev, struct pnp_resource_table
                         res->port_resource[tmp].flags = IORESOURCE_IO;
                 }
                 for (tmp = 0; tmp < PNP_MAX_MEM; tmp++) {
-                        ret = isapnp_read_word(ISAPNP_CFG_MEM + (tmp << 3)) << 8;
+                        ret =
+                            isapnp_read_word(ISAPNP_CFG_MEM + (tmp << 3)) << 8;
                         if (!ret)
                                 continue;
                         res->mem_resource[tmp].start = ret;
                         res->mem_resource[tmp].flags = IORESOURCE_MEM;
                 }
                 for (tmp = 0; tmp < PNP_MAX_IRQ; tmp++) {
-                        ret = (isapnp_read_word(ISAPNP_CFG_IRQ + (tmp << 1)) >> 8);
+                        ret =
+                            (isapnp_read_word(ISAPNP_CFG_IRQ + (tmp << 1)) >>
+                             8);
                         if (!ret)
                                 continue;
-                        res->irq_resource[tmp].start = res->irq_resource[tmp].end = ret;
+                        res->irq_resource[tmp].start =
+                            res->irq_resource[tmp].end = ret;
                         res->irq_resource[tmp].flags = IORESOURCE_IRQ;
                 }
                 for (tmp = 0; tmp < PNP_MAX_DMA; tmp++) {
                         ret = isapnp_read_byte(ISAPNP_CFG_DMA + tmp);
                         if (ret == 4)
                                 continue;
-                        res->dma_resource[tmp].start = res->dma_resource[tmp].end = ret;
+                        res->dma_resource[tmp].start =
+                            res->dma_resource[tmp].end = ret;
                         res->dma_resource[tmp].flags = IORESOURCE_DMA;
                 }
         }
         return 0;
 }
 
-static int isapnp_get_resources(struct pnp_dev *dev, struct pnp_resource_table * res)
+static int isapnp_get_resources(struct pnp_dev *dev,
+                                struct pnp_resource_table *res)
 {
         int ret;
         pnp_init_resource_table(res);
@@ -994,24 +1000,44 @@ static int isapnp_get_resources(struct pnp_dev *dev, struct pnp_resource_table *
         return ret;
 }
 
-static int isapnp_set_resources(struct pnp_dev *dev, struct pnp_resource_table * res)
+static int isapnp_set_resources(struct pnp_dev *dev,
+                                struct pnp_resource_table *res)
 {
         int tmp;
 
         isapnp_cfg_begin(dev->card->number, dev->number);
         dev->active = 1;
-        for (tmp = 0; tmp < PNP_MAX_PORT && (res->port_resource[tmp].flags & (IORESOURCE_IO | IORESOURCE_UNSET)) == IORESOURCE_IO; tmp++)
-                isapnp_write_word(ISAPNP_CFG_PORT+(tmp<<1), res->port_resource[tmp].start);
-        for (tmp = 0; tmp < PNP_MAX_IRQ && (res->irq_resource[tmp].flags & (IORESOURCE_IRQ | IORESOURCE_UNSET)) == IORESOURCE_IRQ; tmp++) {
+        for (tmp = 0;
+             tmp < PNP_MAX_PORT
+             && (res->port_resource[tmp].
+                 flags & (IORESOURCE_IO | IORESOURCE_UNSET)) == IORESOURCE_IO;
+             tmp++)
+                isapnp_write_word(ISAPNP_CFG_PORT + (tmp << 1),
+                                  res->port_resource[tmp].start);
+        for (tmp = 0;
+             tmp < PNP_MAX_IRQ
+             && (res->irq_resource[tmp].
+                 flags & (IORESOURCE_IRQ | IORESOURCE_UNSET)) == IORESOURCE_IRQ;
+             tmp++) {
                 int irq = res->irq_resource[tmp].start;
                 if (irq == 2)
                         irq = 9;
-                isapnp_write_byte(ISAPNP_CFG_IRQ+(tmp<<1), irq);
+                isapnp_write_byte(ISAPNP_CFG_IRQ + (tmp << 1), irq);
         }
-        for (tmp = 0; tmp < PNP_MAX_DMA && (res->dma_resource[tmp].flags & (IORESOURCE_DMA | IORESOURCE_UNSET)) == IORESOURCE_DMA; tmp++)
-                isapnp_write_byte(ISAPNP_CFG_DMA+tmp, res->dma_resource[tmp].start);
-        for (tmp = 0; tmp < PNP_MAX_MEM && (res->mem_resource[tmp].flags & (IORESOURCE_MEM | IORESOURCE_UNSET)) == IORESOURCE_MEM; tmp++)
-                isapnp_write_word(ISAPNP_CFG_MEM+(tmp<<3), (res->mem_resource[tmp].start >> 8) & 0xffff);
+        for (tmp = 0;
+             tmp < PNP_MAX_DMA
+             && (res->dma_resource[tmp].
+                 flags & (IORESOURCE_DMA | IORESOURCE_UNSET)) == IORESOURCE_DMA;
+             tmp++)
+                isapnp_write_byte(ISAPNP_CFG_DMA + tmp,
+                                  res->dma_resource[tmp].start);
+        for (tmp = 0;
+             tmp < PNP_MAX_MEM
+             && (res->mem_resource[tmp].
+                 flags & (IORESOURCE_MEM | IORESOURCE_UNSET)) == IORESOURCE_MEM;
+             tmp++)
+                isapnp_write_word(ISAPNP_CFG_MEM + (tmp << 3),
+                                  (res->mem_resource[tmp].start >> 8) & 0xffff);
         /* FIXME: We aren't handling 32bit mems properly here */
         isapnp_activate(dev->number);
         isapnp_cfg_end();
@@ -1030,9 +1056,9 @@ static int isapnp_disable_resources(struct pnp_dev *dev)
 }
 
 struct pnp_protocol isapnp_protocol = {
-        .name   = "ISA Plug and Play",
-        .get    = isapnp_get_resources,
-        .set    = isapnp_set_resources,
+        .name = "ISA Plug and Play",
+        .get = isapnp_get_resources,
+        .set = isapnp_set_resources,
         .disable = isapnp_disable_resources,
 };
 
@@ -1053,31 +1079,36 @@ static int __init isapnp_init(void)
 #endif
 #ifdef ISAPNP_REGION_OK
         if (!request_region(_PIDXR, 1, "isapnp index")) {
-                printk(KERN_ERR "isapnp: Index Register 0x%x already used\n", _PIDXR);
+                printk(KERN_ERR "isapnp: Index Register 0x%x already used\n",
+                       _PIDXR);
                 return -EBUSY;
         }
 #endif
         if (!request_region(_PNPWRP, 1, "isapnp write")) {
-                printk(KERN_ERR "isapnp: Write Data Register 0x%x already used\n", _PNPWRP);
+                printk(KERN_ERR
+                       "isapnp: Write Data Register 0x%x already used\n",
+                       _PNPWRP);
 #ifdef ISAPNP_REGION_OK
                 release_region(_PIDXR, 1);
 #endif
                 return -EBUSY;
         }
 
-        if(pnp_register_protocol(&isapnp_protocol)<0)
+        if (pnp_register_protocol(&isapnp_protocol) < 0)
                 return -EBUSY;
 
         /*
-         *      Print a message. The existing ISAPnP code is hanging machines
-         *      so let the user know where.
+         *      Print a message. The existing ISAPnP code is hanging machines
+         *      so let the user know where.
          */
-         
+
         printk(KERN_INFO "isapnp: Scanning for PnP cards...\n");
         if (isapnp_rdp >= 0x203 && isapnp_rdp <= 0x3ff) {
                 isapnp_rdp |= 3;
                 if (!request_region(isapnp_rdp, 1, "isapnp read")) {
-                        printk(KERN_ERR "isapnp: Read Data Register 0x%x already used\n", isapnp_rdp);
+                        printk(KERN_ERR
+                               "isapnp: Read Data Register 0x%x already used\n",
+                               isapnp_rdp);
 #ifdef ISAPNP_REGION_OK
                         release_region(_PIDXR, 1);
 #endif
@@ -1089,14 +1120,14 @@ static int __init isapnp_init(void)
         isapnp_detected = 1;
         if (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff) {
                 cards = isapnp_isolate();
-                if (cards < 0 || 
-                    (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
+                if (cards < 0 || (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
 #ifdef ISAPNP_REGION_OK
                         release_region(_PIDXR, 1);
 #endif
                         release_region(_PNPWRP, 1);
                         isapnp_detected = 0;
-                        printk(KERN_INFO "isapnp: No Plug & Play device found\n");
+                        printk(KERN_INFO
+                               "isapnp: No Plug & Play device found\n");
                         return 0;
                 }
                 request_region(isapnp_rdp, 1, "isapnp read");
@@ -1104,19 +1135,23 @@ static int __init isapnp_init(void)
         isapnp_build_device_list();
         cards = 0;
 
-        protocol_for_each_card(&isapnp_protocol,card) {
+        protocol_for_each_card(&isapnp_protocol, card) {
                 cards++;
                 if (isapnp_verbose) {
-                        printk(KERN_INFO "isapnp: Card '%s'\n", card->name[0]?card->name:"Unknown");
+                        printk(KERN_INFO "isapnp: Card '%s'\n",
+                               card->name[0] ? card->name : "Unknown");
                         if (isapnp_verbose < 2)
                                 continue;
-                        card_for_each_dev(card,dev) {
-                                printk(KERN_INFO "isapnp:   Device '%s'\n", dev->name[0]?dev->name:"Unknown");
+                        card_for_each_dev(card, dev) {
+                                printk(KERN_INFO "isapnp:   Device '%s'\n",
+                                       dev->name[0] ? dev->name : "Unknown");
                         }
                 }
         }
         if (cards) {
-                printk(KERN_INFO "isapnp: %i Plug & Play card%s detected total\n", cards, cards>1?"s":"");
+                printk(KERN_INFO
+                       "isapnp: %i Plug & Play card%s detected total\n", cards,
+                       cards > 1 ? "s" : "");
         } else {
                 printk(KERN_INFO "isapnp: No Plug & Play card found\n");
         }
@@ -1141,11 +1176,10 @@ __setup("noisapnp", isapnp_setup_disable);
 
 static int __init isapnp_setup_isapnp(char *str)
 {
-        (void)((get_option(&str,&isapnp_rdp) == 2) &&
-               (get_option(&str,&isapnp_reset) == 2) &&
-               (get_option(&str,&isapnp_verbose) == 2));
+        (void)((get_option(&str, &isapnp_rdp) == 2) &&
+               (get_option(&str, &isapnp_reset) == 2) &&
+               (get_option(&str, &isapnp_verbose) == 2));
         return 1;
 }
 
 __setup("isapnp=", isapnp_setup_isapnp);
-
diff --git a/drivers/pnp/isapnp/proc.c b/drivers/pnp/isapnp/proc.c
index 40b724ebe23b..3fbc0f9ffc26 100644
--- a/drivers/pnp/isapnp/proc.c
+++ b/drivers/pnp/isapnp/proc.c
@@ -2,7 +2,6 @@
  *  ISA Plug & Play support
  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
  *
- *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
  *   the Free Software Foundation; either version 2 of the License, or
@@ -16,7 +15,6 @@
  *   You should have received a copy of the GNU General Public License
  *   along with this program; if not, write to the Free Software
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
  */
 
 #include <linux/module.h>
@@ -54,7 +52,8 @@ static loff_t isapnp_proc_bus_lseek(struct file *file, loff_t off, int whence)
         return (file->f_pos = new);
 }
 
-static ssize_t isapnp_proc_bus_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
+static ssize_t isapnp_proc_bus_read(struct file *file, char __user * buf,
+                                    size_t nbytes, loff_t * ppos)
 {
         struct inode *ino = file->f_path.dentry->d_inode;
         struct proc_dir_entry *dp = PDE(ino);
@@ -74,7 +73,7 @@ static ssize_t isapnp_proc_bus_read(struct file *file, char __user *buf, size_t
                 return -EINVAL;
 
         isapnp_cfg_begin(dev->card->number, dev->number);
-        for ( ; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
+        for (; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
                 unsigned char val;
                 val = isapnp_read_byte(pos);
                 __put_user(val, buf);
@@ -85,10 +84,9 @@ static ssize_t isapnp_proc_bus_read(struct file *file, char __user *buf, size_t
         return nbytes;
 }
 
-static const struct file_operations isapnp_proc_bus_file_operations =
-{
-        .llseek         = isapnp_proc_bus_lseek,
-        .read           = isapnp_proc_bus_read,
+static const struct file_operations isapnp_proc_bus_file_operations = {
+        .llseek = isapnp_proc_bus_lseek,
+        .read = isapnp_proc_bus_read,
 };
 
 static int isapnp_proc_attach_device(struct pnp_dev *dev)
@@ -139,13 +137,14 @@ static int __exit isapnp_proc_detach_bus(struct pnp_card *bus)
         remove_proc_entry(name, isapnp_proc_bus_dir);
         return 0;
 }
-#endif /* MODULE */
+#endif                          /* MODULE */
 
 int __init isapnp_proc_init(void)
 {
         struct pnp_dev *dev;
+
         isapnp_proc_bus_dir = proc_mkdir("isapnp", proc_bus);
-        protocol_for_each_dev(&isapnp_protocol,dev) {
+        protocol_for_each_dev(&isapnp_protocol, dev) {
                 isapnp_proc_attach_device(dev);
         }
         return 0;
@@ -167,4 +166,4 @@ int __exit isapnp_proc_done(void)
                 remove_proc_entry("isapnp", proc_bus);
         return 0;
 }
-#endif /* MODULE */
+#endif                          /* MODULE */
diff --git a/drivers/pnp/manager.c b/drivers/pnp/manager.c
index 57e6ab1004d0..3bda513a6bd3 100644
--- a/drivers/pnp/manager.c
+++ b/drivers/pnp/manager.c
@@ -3,7 +3,6 @@
  *
  * based on isapnp.c resource management (c) Jaroslav Kysela <perex@suse.cz>
  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/errno.h>
@@ -26,7 +25,8 @@ static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
                 return -EINVAL;
 
         if (idx >= PNP_MAX_PORT) {
-                pnp_err("More than 4 ports is incompatible with pnp specifications.");
+                pnp_err
+                    ("More than 4 ports is incompatible with pnp specifications.");
                 /* pretend we were successful so at least the manager won't try again */
                 return 1;
         }
@@ -41,11 +41,11 @@ static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
 
         /* set the initial values */
         *flags |= rule->flags | IORESOURCE_IO;
-        *flags &=  ~IORESOURCE_UNSET;
+        *flags &= ~IORESOURCE_UNSET;
 
         if (!rule->size) {
                 *flags |= IORESOURCE_DISABLED;
-                return 1; /* skip disabled resource requests */
+                return 1;       /* skip disabled resource requests */
         }
 
         *start = rule->min;
@@ -70,7 +70,8 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
                 return -EINVAL;
 
         if (idx >= PNP_MAX_MEM) {
-                pnp_err("More than 8 mems is incompatible with pnp specifications.");
+                pnp_err
+                    ("More than 8 mems is incompatible with pnp specifications.");
                 /* pretend we were successful so at least the manager won't try again */
                 return 1;
         }
@@ -85,7 +86,7 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
 
         /* set the initial values */
         *flags |= rule->flags | IORESOURCE_MEM;
-        *flags &=  ~IORESOURCE_UNSET;
+        *flags &= ~IORESOURCE_UNSET;
 
         /* convert pnp flags to standard Linux flags */
         if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
@@ -99,11 +100,11 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
 
         if (!rule->size) {
                 *flags |= IORESOURCE_DISABLED;
-                return 1; /* skip disabled resource requests */
+                return 1;       /* skip disabled resource requests */
         }
 
         *start = rule->min;
-        *end = *start + rule->size -1;
+        *end = *start + rule->size - 1;
 
         /* run through until pnp_check_mem is happy */
         while (!pnp_check_mem(dev, idx)) {
@@ -115,7 +116,7 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
         return 1;
 }
 
-static int pnp_assign_irq(struct pnp_dev * dev, struct pnp_irq *rule, int idx)
+static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
 {
         resource_size_t *start, *end;
         unsigned long *flags;
@@ -130,7 +131,8 @@ static int pnp_assign_irq(struct pnp_dev * dev, struct pnp_irq *rule, int idx)
                 return -EINVAL;
 
         if (idx >= PNP_MAX_IRQ) {
-                pnp_err("More than 2 irqs is incompatible with pnp specifications.");
+                pnp_err
+                    ("More than 2 irqs is incompatible with pnp specifications.");
                 /* pretend we were successful so at least the manager won't try again */
                 return 1;
         }
@@ -145,11 +147,11 @@ static int pnp_assign_irq(struct pnp_dev * dev, struct pnp_irq *rule, int idx)
 
         /* set the initial values */
         *flags |= rule->flags | IORESOURCE_IRQ;
-        *flags &=  ~IORESOURCE_UNSET;
+        *flags &= ~IORESOURCE_UNSET;
 
         if (bitmap_empty(rule->map, PNP_IRQ_NR)) {
                 *flags |= IORESOURCE_DISABLED;
-                return 1; /* skip disabled resource requests */
+                return 1;       /* skip disabled resource requests */
         }
 
         /* TBD: need check for >16 IRQ */
@@ -159,9 +161,9 @@ static int pnp_assign_irq(struct pnp_dev * dev, struct pnp_irq *rule, int idx)
                 return 1;
         }
         for (i = 0; i < 16; i++) {
-                if(test_bit(xtab[i], rule->map)) {
+                if (test_bit(xtab[i], rule->map)) {
                         *start = *end = xtab[i];
-                        if(pnp_check_irq(dev, idx))
+                        if (pnp_check_irq(dev, idx))
                                 return 1;
                 }
         }
@@ -183,7 +185,8 @@ static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
                 return -EINVAL;
 
         if (idx >= PNP_MAX_DMA) {
-                pnp_err("More than 2 dmas is incompatible with pnp specifications.");
+                pnp_err
+                    ("More than 2 dmas is incompatible with pnp specifications.");
                 /* pretend we were successful so at least the manager won't try again */
                 return 1;
         }
@@ -198,17 +201,17 @@ static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
 
         /* set the initial values */
         *flags |= rule->flags | IORESOURCE_DMA;
-        *flags &=  ~IORESOURCE_UNSET;
+        *flags &= ~IORESOURCE_UNSET;
 
         if (!rule->map) {
                 *flags |= IORESOURCE_DISABLED;
-                return 1; /* skip disabled resource requests */
+                return 1;       /* skip disabled resource requests */
         }
 
         for (i = 0; i < 8; i++) {
-                if(rule->map & (1<<xtab[i])) {
+                if (rule->map & (1 << xtab[i])) {
                         *start = *end = xtab[i];
-                        if(pnp_check_dma(dev, idx))
+                        if (pnp_check_dma(dev, idx))
                                 return 1;
                 }
         }
@@ -218,72 +221,80 @@ static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
 /**
  * pnp_init_resources - Resets a resource table to default values.
  * @table: pointer to the desired resource table
- *
  */
 void pnp_init_resource_table(struct pnp_resource_table *table)
 {
         int idx;
+
         for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
                 table->irq_resource[idx].name = NULL;
                 table->irq_resource[idx].start = -1;
                 table->irq_resource[idx].end = -1;
-                table->irq_resource[idx].flags = IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                table->irq_resource[idx].flags =
+                    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_DMA; idx++) {
                 table->dma_resource[idx].name = NULL;
                 table->dma_resource[idx].start = -1;
                 table->dma_resource[idx].end = -1;
-                table->dma_resource[idx].flags = IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                table->dma_resource[idx].flags =
+                    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_PORT; idx++) {
                 table->port_resource[idx].name = NULL;
                 table->port_resource[idx].start = 0;
                 table->port_resource[idx].end = 0;
-                table->port_resource[idx].flags = IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                table->port_resource[idx].flags =
+                    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_MEM; idx++) {
                 table->mem_resource[idx].name = NULL;
                 table->mem_resource[idx].start = 0;
                 table->mem_resource[idx].end = 0;
-                table->mem_resource[idx].flags = IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                table->mem_resource[idx].flags =
+                    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
 }
 
 /**
  * pnp_clean_resources - clears resources that were not manually set
  * @res: the resources to clean
- *
  */
-static void pnp_clean_resource_table(struct pnp_resource_table * res)
+static void pnp_clean_resource_table(struct pnp_resource_table *res)
 {
         int idx;
+
         for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
                 if (!(res->irq_resource[idx].flags & IORESOURCE_AUTO))
                         continue;
                 res->irq_resource[idx].start = -1;
                 res->irq_resource[idx].end = -1;
-                res->irq_resource[idx].flags = IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                res->irq_resource[idx].flags =
+                    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_DMA; idx++) {
                 if (!(res->dma_resource[idx].flags & IORESOURCE_AUTO))
                         continue;
                 res->dma_resource[idx].start = -1;
                 res->dma_resource[idx].end = -1;
-                res->dma_resource[idx].flags = IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                res->dma_resource[idx].flags =
+                    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_PORT; idx++) {
                 if (!(res->port_resource[idx].flags & IORESOURCE_AUTO))
                         continue;
                 res->port_resource[idx].start = 0;
                 res->port_resource[idx].end = 0;
-                res->port_resource[idx].flags = IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                res->port_resource[idx].flags =
+                    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
         for (idx = 0; idx < PNP_MAX_MEM; idx++) {
                 if (!(res->mem_resource[idx].flags & IORESOURCE_AUTO))
                         continue;
                 res->mem_resource[idx].start = 0;
                 res->mem_resource[idx].end = 0;
-                res->mem_resource[idx].flags = IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
+                res->mem_resource[idx].flags =
+                    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
         }
 }
 
@@ -306,7 +317,7 @@ static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
                 return -ENODEV;
 
         down(&pnp_res_mutex);
-        pnp_clean_resource_table(&dev->res); /* start with a fresh slate */
+        pnp_clean_resource_table(&dev->res);    /* start with a fresh slate */
         if (dev->independent) {
                 port = dev->independent->port;
                 mem = dev->independent->mem;
@@ -341,10 +352,11 @@ static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
         if (depnum) {
                 struct pnp_option *dep;
                 int i;
-                for (i=1,dep=dev->dependent; i<depnum; i++, dep=dep->next)
-                        if(!dep)
+                for (i = 1, dep = dev->dependent; i < depnum;
+                     i++, dep = dep->next)
+                        if (!dep)
                                 goto fail;
-                port =dep->port;
+                port = dep->port;
                 mem = dep->mem;
                 irq = dep->irq;
                 dma = dep->dma;
@@ -378,7 +390,7 @@ static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
         up(&pnp_res_mutex);
         return 1;
 
-fail:
+      fail:
         pnp_clean_resource_table(&dev->res);
         up(&pnp_res_mutex);
         return 0;
@@ -392,10 +404,12 @@ fail:
  *
  * This function can be used by drivers that want to manually set thier resources.
  */
-int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table * res, int mode)
+int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res,
+                          int mode)
 {
         int i;
-        struct pnp_resource_table * bak;
+        struct pnp_resource_table *bak;
+
         if (!dev || !res)
                 return -EINVAL;
         if (!pnp_can_configure(dev))
@@ -409,19 +423,19 @@ int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table * res,
         dev->res = *res;
         if (!(mode & PNP_CONFIG_FORCE)) {
                 for (i = 0; i < PNP_MAX_PORT; i++) {
-                        if(!pnp_check_port(dev,i))
+                        if (!pnp_check_port(dev, i))
                                 goto fail;
                 }
                 for (i = 0; i < PNP_MAX_MEM; i++) {
-                        if(!pnp_check_mem(dev,i))
+                        if (!pnp_check_mem(dev, i))
                                 goto fail;
                 }
                 for (i = 0; i < PNP_MAX_IRQ; i++) {
-                        if(!pnp_check_irq(dev,i))
+                        if (!pnp_check_irq(dev, i))
                                 goto fail;
                 }
                 for (i = 0; i < PNP_MAX_DMA; i++) {
-                        if(!pnp_check_dma(dev,i))
+                        if (!pnp_check_dma(dev, i))
                                 goto fail;
                 }
         }
@@ -430,7 +444,7 @@ int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table * res,
         kfree(bak);
         return 0;
 
-fail:
+      fail:
         dev->res = *bak;
         up(&pnp_res_mutex);
         kfree(bak);
@@ -440,18 +454,18 @@ fail:
 /**
  * pnp_auto_config_dev - automatically assigns resources to a device
  * @dev: pointer to the desired device
- *
  */
 int pnp_auto_config_dev(struct pnp_dev *dev)
 {
         struct pnp_option *dep;
         int i = 1;
 
-        if(!dev)
+        if (!dev)
                 return -EINVAL;
 
-        if(!pnp_can_configure(dev)) {
-                pnp_dbg("Device %s does not support resource configuration.", dev->dev.bus_id);
+        if (!pnp_can_configure(dev)) {
+                pnp_dbg("Device %s does not support resource configuration.",
+                        dev->dev.bus_id);
                 return -ENODEV;
         }
 
@@ -476,23 +490,22 @@ int pnp_auto_config_dev(struct pnp_dev *dev)
  * pnp_start_dev - low-level start of the PnP device
  * @dev: pointer to the desired device
  *
- * assumes that resources have alread been allocated
+ * assumes that resources have already been allocated
  */
-
 int pnp_start_dev(struct pnp_dev *dev)
 {
         if (!pnp_can_write(dev)) {
-                pnp_dbg("Device %s does not support activation.", dev->dev.bus_id);
+                pnp_dbg("Device %s does not support activation.",
+                        dev->dev.bus_id);
                 return -EINVAL;
         }
 
-        if (dev->protocol->set(dev, &dev->res)<0) {
+        if (dev->protocol->set(dev, &dev->res) < 0) {
                 pnp_err("Failed to activate device %s.", dev->dev.bus_id);
                 return -EIO;
         }
 
         pnp_info("Device %s activated.", dev->dev.bus_id);
-
         return 0;
 }
 
@@ -502,20 +515,19 @@ int pnp_start_dev(struct pnp_dev *dev)
  *
  * does not free resources
  */
-
 int pnp_stop_dev(struct pnp_dev *dev)
 {
         if (!pnp_can_disable(dev)) {
-                pnp_dbg("Device %s does not support disabling.", dev->dev.bus_id);
+                pnp_dbg("Device %s does not support disabling.",
+                        dev->dev.bus_id);
                 return -EINVAL;
         }
-        if (dev->protocol->disable(dev)<0) {
+        if (dev->protocol->disable(dev) < 0) {
                 pnp_err("Failed to disable device %s.", dev->dev.bus_id);
                 return -EIO;
         }
 
         pnp_info("Device %s disabled.", dev->dev.bus_id);
-
         return 0;
 }
 
@@ -531,9 +543,8 @@ int pnp_activate_dev(struct pnp_dev *dev)
 
         if (!dev)
                 return -EINVAL;
-        if (dev->active) {
-                return 0; /* the device is already active */
-        }
+        if (dev->active)
+                return 0;       /* the device is already active */
 
         /* ensure resources are allocated */
         if (pnp_auto_config_dev(dev))
@@ -544,7 +555,6 @@ int pnp_activate_dev(struct pnp_dev *dev)
                 return error;
 
         dev->active = 1;
-
         return 1;
 }
 
@@ -558,11 +568,10 @@ int pnp_disable_dev(struct pnp_dev *dev)
 {
         int error;
 
-        if (!dev)
-                return -EINVAL;
-        if (!dev->active) {
-                return 0; /* the device is already disabled */
-        }
+        if (!dev)
+                return -EINVAL;
+        if (!dev->active)
+                return 0;       /* the device is already disabled */
 
         error = pnp_stop_dev(dev);
         if (error)
@@ -583,10 +592,9 @@ int pnp_disable_dev(struct pnp_dev *dev)
  * @resource: pointer to resource to be changed
  * @start: start of region
  * @size: size of region
- *
  */
 void pnp_resource_change(struct resource *resource, resource_size_t start,
-                                resource_size_t size)
+                         resource_size_t size)
 {
         if (resource == NULL)
                 return;
@@ -595,11 +603,7 @@ void pnp_resource_change(struct resource *resource, resource_size_t start,
         resource->end = start + size - 1;
 }
 
-
 EXPORT_SYMBOL(pnp_manual_config_dev);
-#if 0
-EXPORT_SYMBOL(pnp_auto_config_dev);
-#endif
 EXPORT_SYMBOL(pnp_start_dev);
 EXPORT_SYMBOL(pnp_stop_dev);
 EXPORT_SYMBOL(pnp_activate_dev);
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index fcd32ac575c3..6a2a3c2f4d5e 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -34,13 +34,13 @@ static int num = 0;
  * used by the kernel (PCI root, ...), as it is harmless and there were
  * already present in pnpbios. But there is an exception for devices that
  * have irqs (PIC, Timer) because we call acpi_register_gsi.
- * Finaly only devices that have a CRS method need to be in this list.
+ * Finally, only devices that have a CRS method need to be in this list.
  */
-static __initdata struct acpi_device_id excluded_id_list[] ={
-        {"PNP0C09", 0}, /* EC */
-        {"PNP0C0F", 0}, /* Link device */
-        {"PNP0000", 0}, /* PIC */
-        {"PNP0100", 0}, /* Timer */
+static struct __initdata acpi_device_id excluded_id_list[] = {
+        {"PNP0C09", 0},         /* EC */
+        {"PNP0C0F", 0},         /* Link device */
+        {"PNP0000", 0},         /* PIC */
+        {"PNP0100", 0},         /* Timer */
         {"", 0},
 };
 
@@ -84,15 +84,18 @@ static void __init pnpidacpi_to_pnpid(char *id, char *str)
         str[7] = '\0';
 }
 
-static int pnpacpi_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
+static int pnpacpi_get_resources(struct pnp_dev *dev,
+                                 struct pnp_resource_table *res)
 {
         acpi_status status;
-        status = pnpacpi_parse_allocated_resource((acpi_handle)dev->data,
-                &dev->res);
+
+        status = pnpacpi_parse_allocated_resource((acpi_handle) dev->data,
+                                                  &dev->res);
         return ACPI_FAILURE(status) ? -ENODEV : 0;
 }
 
-static int pnpacpi_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
+static int pnpacpi_set_resources(struct pnp_dev *dev,
+                                 struct pnp_resource_table *res)
 {
         acpi_handle handle = dev->data;
         struct acpi_buffer buffer;
@@ -119,27 +122,29 @@ static int pnpacpi_disable_resources(struct pnp_dev *dev)
         acpi_status status;
 
         /* acpi_unregister_gsi(pnp_irq(dev, 0)); */
-        status = acpi_evaluate_object((acpi_handle)dev->data,
-                "_DIS", NULL, NULL);
+        status = acpi_evaluate_object((acpi_handle) dev->data,
+                                      "_DIS", NULL, NULL);
         return ACPI_FAILURE(status) ? -ENODEV : 0;
 }
 
 static int pnpacpi_suspend(struct pnp_dev *dev, pm_message_t state)
 {
-        return acpi_bus_set_power((acpi_handle)dev->data,
-                acpi_pm_device_sleep_state(&dev->dev,
-                device_may_wakeup(&dev->dev), NULL));
+        return acpi_bus_set_power((acpi_handle) dev->data,
+                                  acpi_pm_device_sleep_state(&dev->dev,
+                                                             device_may_wakeup
+                                                             (&dev->dev),
+                                                             NULL));
 }
 
 static int pnpacpi_resume(struct pnp_dev *dev)
 {
-        return acpi_bus_set_power((acpi_handle)dev->data, ACPI_STATE_D0);
+        return acpi_bus_set_power((acpi_handle) dev->data, ACPI_STATE_D0);
 }
 
 static struct pnp_protocol pnpacpi_protocol = {
-        .name   = "Plug and Play ACPI",
-        .get    = pnpacpi_get_resources,
-        .set    = pnpacpi_set_resources,
+        .name    = "Plug and Play ACPI",
+        .get     = pnpacpi_get_resources,
+        .set     = pnpacpi_set_resources,
         .disable = pnpacpi_disable_resources,
         .suspend = pnpacpi_suspend,
         .resume = pnpacpi_resume,
@@ -154,17 +159,17 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
 
         status = acpi_get_handle(device->handle, "_CRS", &temp);
         if (ACPI_FAILURE(status) || !ispnpidacpi(acpi_device_hid(device)) ||
-                is_exclusive_device(device))
+            is_exclusive_device(device))
                 return 0;
 
         pnp_dbg("ACPI device : hid %s", acpi_device_hid(device));
-        dev =  kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
+        dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
         if (!dev) {
                 pnp_err("Out of memory");
                 return -ENOMEM;
         }
         dev->data = device->handle;
-        /* .enabled means if the device can decode the resources */
+        /* .enabled means the device can decode the resources */
         dev->active = device->status.enabled;
         status = acpi_get_handle(device->handle, "_SRS", &temp);
         if (ACPI_SUCCESS(status))
@@ -194,20 +199,23 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
         pnpidacpi_to_pnpid(acpi_device_hid(device), dev_id->id);
         pnp_add_id(dev_id, dev);
 
-        if(dev->active) {
+        if (dev->active) {
                 /* parse allocated resource */
-                status = pnpacpi_parse_allocated_resource(device->handle, &dev->res);
+                status = pnpacpi_parse_allocated_resource(device->handle,
+                                                          &dev->res);
                 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
-                        pnp_err("PnPACPI: METHOD_NAME__CRS failure for %s", dev_id->id);
+                        pnp_err("PnPACPI: METHOD_NAME__CRS failure for %s",
+                                dev_id->id);
                         goto err1;
                 }
         }
 
-        if(dev->capabilities & PNP_CONFIGURABLE) {
+        if (dev->capabilities & PNP_CONFIGURABLE) {
                 status = pnpacpi_parse_resource_option_data(device->handle,
-                        dev);
+                                                            dev);
                 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
-                        pnp_err("PnPACPI: METHOD_NAME__PRS failure for %s", dev_id->id);
+                        pnp_err("PnPACPI: METHOD_NAME__PRS failure for %s",
+                                dev_id->id);
                         goto err1;
                 }
         }
@@ -233,18 +241,19 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
         if (!dev->active)
                 pnp_init_resource_table(&dev->res);
         pnp_add_device(dev);
-        num ++;
+        num++;
 
         return AE_OK;
-err1:
+      err1:
         kfree(dev_id);
-err:
+      err:
         kfree(dev);
         return -EINVAL;
 }
 
 static acpi_status __init pnpacpi_add_device_handler(acpi_handle handle,
-        u32 lvl, void *context, void **rv)
+                                                     u32 lvl, void *context,
+                                                     void **rv)
 {
         struct acpi_device *device;
 
@@ -257,23 +266,22 @@ static acpi_status __init pnpacpi_add_device_handler(acpi_handle handle,
 
 static int __init acpi_pnp_match(struct device *dev, void *_pnp)
 {
-        struct acpi_device      *acpi = to_acpi_device(dev);
-        struct pnp_dev          *pnp = _pnp;
+        struct acpi_device *acpi = to_acpi_device(dev);
+        struct pnp_dev *pnp = _pnp;
 
         /* true means it matched */
         return acpi->flags.hardware_id
-                && !acpi_get_physical_device(acpi->handle)
-                && compare_pnp_id(pnp->id, acpi->pnp.hardware_id);
+            && !acpi_get_physical_device(acpi->handle)
+            && compare_pnp_id(pnp->id, acpi->pnp.hardware_id);
 }
 
-static int __init acpi_pnp_find_device(struct device *dev, acpi_handle *handle)
+static int __init acpi_pnp_find_device(struct device *dev, acpi_handle * handle)
 {
-        struct device           *adev;
-        struct acpi_device      *acpi;
+        struct device *adev;
+        struct acpi_device *acpi;
 
         adev = bus_find_device(&acpi_bus_type, NULL,
-                        to_pnp_dev(dev),
-                        acpi_pnp_match);
+                               to_pnp_dev(dev), acpi_pnp_match);
         if (!adev)
                 return -ENODEV;
 
@@ -287,7 +295,7 @@ static int __init acpi_pnp_find_device(struct device *dev, acpi_handle *handle)
  * pnpdev->dev.archdata.acpi_handle point to its ACPI sibling.
  */
 static struct acpi_bus_type __initdata acpi_pnp_bus = {
-        .bus = &pnp_bus_type,
+        .bus         = &pnp_bus_type,
         .find_device = acpi_pnp_find_device,
 };
 
@@ -307,6 +315,7 @@ static int __init pnpacpi_init(void)
         pnp_platform_devices = 1;
         return 0;
 }
+
 subsys_initcall(pnpacpi_init);
 
 static int __init pnpacpi_setup(char *str)
@@ -317,8 +326,5 @@ static int __init pnpacpi_setup(char *str)
                 pnpacpi_disabled = 1;
         return 1;
 }
-__setup("pnpacpi=", pnpacpi_setup);
 
-#if 0
-EXPORT_SYMBOL(pnpacpi_protocol);
-#endif
+__setup("pnpacpi=", pnpacpi_setup);
diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c
index 118ac9779b3c..ce5027feb3da 100644
--- a/drivers/pnp/pnpacpi/rsparser.c
+++ b/drivers/pnp/pnpacpi/rsparser.c
@@ -40,8 +40,7 @@ static int irq_flags(int triggering, int polarity)
                         flag = IORESOURCE_IRQ_LOWLEVEL;
                 else
                         flag = IORESOURCE_IRQ_HIGHLEVEL;
-        }
-        else {
+        } else {
                 if (polarity == ACPI_ACTIVE_LOW)
                         flag = IORESOURCE_IRQ_LOWEDGE;
                 else
@@ -72,9 +71,9 @@ static void decode_irq_flags(int flag, int *triggering, int *polarity)
         }
 }
 
-static void
-pnpacpi_parse_allocated_irqresource(struct pnp_resource_table *res, u32 gsi,
-        int triggering, int polarity, int shareable)
+static void pnpacpi_parse_allocated_irqresource(struct pnp_resource_table *res,
+                                                u32 gsi, int triggering,
+                                                int polarity, int shareable)
 {
         int i = 0;
         int irq;
@@ -83,12 +82,12 @@ pnpacpi_parse_allocated_irqresource(struct pnp_resource_table *res, u32 gsi,
                 return;
 
         while (!(res->irq_resource[i].flags & IORESOURCE_UNSET) &&
-                        i < PNP_MAX_IRQ)
+               i < PNP_MAX_IRQ)
                 i++;
         if (i >= PNP_MAX_IRQ)
                 return;
 
-        res->irq_resource[i].flags = IORESOURCE_IRQ;  // Also clears _UNSET flag
+        res->irq_resource[i].flags = IORESOURCE_IRQ;    // Also clears _UNSET flag
         res->irq_resource[i].flags |= irq_flags(triggering, polarity);
         irq = acpi_register_gsi(gsi, triggering, polarity);
         if (irq < 0) {
@@ -147,17 +146,19 @@ static int dma_flags(int type, int bus_master, int transfer)
         return flags;
 }
 
-static void
-pnpacpi_parse_allocated_dmaresource(struct pnp_resource_table *res, u32 dma,
-        int type, int bus_master, int transfer)
+static void pnpacpi_parse_allocated_dmaresource(struct pnp_resource_table *res,
+                                                u32 dma, int type,
+                                                int bus_master, int transfer)
 {
         int i = 0;
+
         while (i < PNP_MAX_DMA &&
-                        !(res->dma_resource[i].flags & IORESOURCE_UNSET))
+               !(res->dma_resource[i].flags & IORESOURCE_UNSET))
                 i++;
         if (i < PNP_MAX_DMA) {
-                res->dma_resource[i].flags = IORESOURCE_DMA;  // Also clears _UNSET flag
-                res->dma_resource[i].flags |= dma_flags(type, bus_master, transfer);
+                res->dma_resource[i].flags = IORESOURCE_DMA;    // Also clears _UNSET flag
+                res->dma_resource[i].flags |=
+                    dma_flags(type, bus_master, transfer);
                 if (dma == -1) {
                         res->dma_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
@@ -167,19 +168,19 @@ pnpacpi_parse_allocated_dmaresource(struct pnp_resource_table *res, u32 dma,
         }
 }
 
-static void
-pnpacpi_parse_allocated_ioresource(struct pnp_resource_table *res,
-        u64 io, u64 len, int io_decode)
+static void pnpacpi_parse_allocated_ioresource(struct pnp_resource_table *res,
+                                               u64 io, u64 len, int io_decode)
 {
         int i = 0;
+
         while (!(res->port_resource[i].flags & IORESOURCE_UNSET) &&
-                        i < PNP_MAX_PORT)
+               i < PNP_MAX_PORT)
                 i++;
         if (i < PNP_MAX_PORT) {
-                res->port_resource[i].flags = IORESOURCE_IO;  // Also clears _UNSET flag
+                res->port_resource[i].flags = IORESOURCE_IO;    // Also clears _UNSET flag
                 if (io_decode == ACPI_DECODE_16)
                         res->port_resource[i].flags |= PNP_PORT_FLAG_16BITADDR;
-                if (len <= 0 || (io + len -1) >= 0x10003) {
+                if (len <= 0 || (io + len - 1) >= 0x10003) {
                         res->port_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
@@ -188,21 +189,22 @@ pnpacpi_parse_allocated_ioresource(struct pnp_resource_table *res,
         }
 }
 
-static void
-pnpacpi_parse_allocated_memresource(struct pnp_resource_table *res,
-        u64 mem, u64 len, int write_protect)
+static void pnpacpi_parse_allocated_memresource(struct pnp_resource_table *res,
+                                                u64 mem, u64 len,
+                                                int write_protect)
 {
         int i = 0;
+
         while (!(res->mem_resource[i].flags & IORESOURCE_UNSET) &&
-                        (i < PNP_MAX_MEM))
+               (i < PNP_MAX_MEM))
                 i++;
         if (i < PNP_MAX_MEM) {
-                res->mem_resource[i].flags = IORESOURCE_MEM;  // Also clears _UNSET flag
+                res->mem_resource[i].flags = IORESOURCE_MEM;    // Also clears _UNSET flag
                 if (len <= 0) {
                         res->mem_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
-                if(write_protect == ACPI_READ_WRITE_MEMORY)
+                if (write_protect == ACPI_READ_WRITE_MEMORY)
                         res->mem_resource[i].flags |= IORESOURCE_MEM_WRITEABLE;
 
                 res->mem_resource[i].start = mem;
@@ -210,9 +212,8 @@ pnpacpi_parse_allocated_memresource(struct pnp_resource_table *res,
         }
 }
 
-static void
-pnpacpi_parse_allocated_address_space(struct pnp_resource_table *res_table,
-        struct acpi_resource *res)
+static void pnpacpi_parse_allocated_address_space(struct pnp_resource_table *res_table,
+                                                  struct acpi_resource *res)
 {
         struct acpi_resource_address64 addr, *p = &addr;
         acpi_status status;
@@ -220,7 +221,7 @@ pnpacpi_parse_allocated_address_space(struct pnp_resource_table *res_table,
         status = acpi_resource_to_address64(res, p);
         if (!ACPI_SUCCESS(status)) {
                 pnp_warn("PnPACPI: failed to convert resource type %d",
-                        res->type);
+                         res->type);
                 return;
         }
 
@@ -229,17 +230,20 @@ pnpacpi_parse_allocated_address_space(struct pnp_resource_table *res_table,
 
         if (p->resource_type == ACPI_MEMORY_RANGE)
                 pnpacpi_parse_allocated_memresource(res_table,
-                                p->minimum, p->address_length, p->info.mem.write_protect);
+                        p->minimum, p->address_length,
+                        p->info.mem.write_protect);
         else if (p->resource_type == ACPI_IO_RANGE)
                 pnpacpi_parse_allocated_ioresource(res_table,
-                                p->minimum, p->address_length,
-                                p->granularity == 0xfff ? ACPI_DECODE_10 : ACPI_DECODE_16);
+                        p->minimum, p->address_length,
+                        p->granularity == 0xfff ? ACPI_DECODE_10 :
+                                ACPI_DECODE_16);
 }
 
 static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
-        void *data)
+                                              void *data)
 {
-        struct pnp_resource_table *res_table = (struct pnp_resource_table *)data;
+        struct pnp_resource_table *res_table =
+            (struct pnp_resource_table *)data;
         int i;
 
         switch (res->type) {
@@ -260,17 +264,17 @@ static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
         case ACPI_RESOURCE_TYPE_DMA:
                 if (res->data.dma.channel_count > 0)
                         pnpacpi_parse_allocated_dmaresource(res_table,
-                                        res->data.dma.channels[0],
-                                        res->data.dma.type,
-                                        res->data.dma.bus_master,
-                                        res->data.dma.transfer);
+                                res->data.dma.channels[0],
+                                res->data.dma.type,
+                                res->data.dma.bus_master,
+                                res->data.dma.transfer);
                 break;
 
         case ACPI_RESOURCE_TYPE_IO:
                 pnpacpi_parse_allocated_ioresource(res_table,
-                                res->data.io.minimum,
-                                res->data.io.address_length,
-                                res->data.io.io_decode);
+                        res->data.io.minimum,
+                        res->data.io.address_length,
+                        res->data.io.io_decode);
                 break;
 
         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
@@ -279,9 +283,9 @@ static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
 
         case ACPI_RESOURCE_TYPE_FIXED_IO:
                 pnpacpi_parse_allocated_ioresource(res_table,
-                                res->data.fixed_io.address,
-                                res->data.fixed_io.address_length,
-                                ACPI_DECODE_10);
+                        res->data.fixed_io.address,
+                        res->data.fixed_io.address_length,
+                        ACPI_DECODE_10);
                 break;
 
         case ACPI_RESOURCE_TYPE_VENDOR:
@@ -292,21 +296,21 @@ static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
 
         case ACPI_RESOURCE_TYPE_MEMORY24:
                 pnpacpi_parse_allocated_memresource(res_table,
-                                res->data.memory24.minimum,
-                                res->data.memory24.address_length,
-                                res->data.memory24.write_protect);
+                        res->data.memory24.minimum,
+                        res->data.memory24.address_length,
+                        res->data.memory24.write_protect);
                 break;
         case ACPI_RESOURCE_TYPE_MEMORY32:
                 pnpacpi_parse_allocated_memresource(res_table,
-                                res->data.memory32.minimum,
-                                res->data.memory32.address_length,
-                                res->data.memory32.write_protect);
+                        res->data.memory32.minimum,
+                        res->data.memory32.address_length,
+                        res->data.memory32.write_protect);
                 break;
         case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
                 pnpacpi_parse_allocated_memresource(res_table,
-                                res->data.fixed_memory32.address,
-                                res->data.fixed_memory32.address_length,
-                                res->data.fixed_memory32.write_protect);
+                        res->data.fixed_memory32.address,
+                        res->data.fixed_memory32.address_length,
+                        res->data.fixed_memory32.write_protect);
                 break;
         case ACPI_RESOURCE_TYPE_ADDRESS16:
         case ACPI_RESOURCE_TYPE_ADDRESS32:
@@ -343,18 +347,21 @@ static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
         return AE_OK;
 }
 
-acpi_status pnpacpi_parse_allocated_resource(acpi_handle handle, struct pnp_resource_table *res)
+acpi_status pnpacpi_parse_allocated_resource(acpi_handle handle,
+                                             struct pnp_resource_table * res)
 {
         /* Blank the resource table values */
         pnp_init_resource_table(res);
 
-        return acpi_walk_resources(handle, METHOD_NAME__CRS, pnpacpi_allocated_resource, res);
+        return acpi_walk_resources(handle, METHOD_NAME__CRS,
+                                   pnpacpi_allocated_resource, res);
 }
 
-static void pnpacpi_parse_dma_option(struct pnp_option *option, struct acpi_resource_dma *p)
+static void pnpacpi_parse_dma_option(struct pnp_option *option,
+                                     struct acpi_resource_dma *p)
 {
         int i;
-        struct pnp_dma * dma;
+        struct pnp_dma *dma;
 
         if (p->channel_count == 0)
                 return;
@@ -362,18 +369,16 @@ static void pnpacpi_parse_dma_option(struct pnp_option *option, struct acpi_reso
         if (!dma)
                 return;
 
-        for(i = 0; i < p->channel_count; i++)
+        for (i = 0; i < p->channel_count; i++)
                 dma->map |= 1 << p->channels[i];
 
         dma->flags = dma_flags(p->type, p->bus_master, p->transfer);
 
         pnp_register_dma_resource(option, dma);
-        return;
 }
 
-
 static void pnpacpi_parse_irq_option(struct pnp_option *option,
-        struct acpi_resource_irq *p)
+                                     struct acpi_resource_irq *p)
 {
         int i;
         struct pnp_irq *irq;
@@ -384,17 +389,16 @@ static void pnpacpi_parse_irq_option(struct pnp_option *option,
         if (!irq)
                 return;
 
-        for(i = 0; i < p->interrupt_count; i++)
+        for (i = 0; i < p->interrupt_count; i++)
                 if (p->interrupts[i])
                         __set_bit(p->interrupts[i], irq->map);
         irq->flags = irq_flags(p->triggering, p->polarity);
 
         pnp_register_irq_resource(option, irq);
-        return;
 }
 
 static void pnpacpi_parse_ext_irq_option(struct pnp_option *option,
-        struct acpi_resource_extended_irq *p)
+                                         struct acpi_resource_extended_irq *p)
 {
         int i;
         struct pnp_irq *irq;
@@ -405,18 +409,16 @@ static void pnpacpi_parse_ext_irq_option(struct pnp_option *option,
         if (!irq)
                 return;
 
-        for(i = 0; i < p->interrupt_count; i++)
+        for (i = 0; i < p->interrupt_count; i++)
                 if (p->interrupts[i])
                         __set_bit(p->interrupts[i], irq->map);
         irq->flags = irq_flags(p->triggering, p->polarity);
 
         pnp_register_irq_resource(option, irq);
-        return;
 }
 
-static void
-pnpacpi_parse_port_option(struct pnp_option *option,
-        struct acpi_resource_io *io)
+static void pnpacpi_parse_port_option(struct pnp_option *option,
+                                      struct acpi_resource_io *io)
 {
         struct pnp_port *port;
 
@@ -430,14 +432,12 @@ pnpacpi_parse_port_option(struct pnp_option *option,
         port->align = io->alignment;
         port->size = io->address_length;
         port->flags = ACPI_DECODE_16 == io->io_decode ?
-                PNP_PORT_FLAG_16BITADDR : 0;
+            PNP_PORT_FLAG_16BITADDR : 0;
         pnp_register_port_resource(option, port);
-        return;
 }
 
-static void
-pnpacpi_parse_fixed_port_option(struct pnp_option *option,
-        struct acpi_resource_fixed_io *io)
+static void pnpacpi_parse_fixed_port_option(struct pnp_option *option,
+                                            struct acpi_resource_fixed_io *io)
 {
         struct pnp_port *port;
 
@@ -451,12 +451,10 @@ pnpacpi_parse_fixed_port_option(struct pnp_option *option,
         port->align = 0;
         port->flags = PNP_PORT_FLAG_FIXED;
         pnp_register_port_resource(option, port);
-        return;
 }
 
-static void
-pnpacpi_parse_mem24_option(struct pnp_option *option,
-        struct acpi_resource_memory24 *p)
+static void pnpacpi_parse_mem24_option(struct pnp_option *option,
+                                       struct acpi_resource_memory24 *p)
 {
         struct pnp_mem *mem;
 
@@ -471,15 +469,13 @@ pnpacpi_parse_mem24_option(struct pnp_option *option,
         mem->size = p->address_length;
 
         mem->flags = (ACPI_READ_WRITE_MEMORY == p->write_protect) ?
-                        IORESOURCE_MEM_WRITEABLE : 0;
+            IORESOURCE_MEM_WRITEABLE : 0;
 
         pnp_register_mem_resource(option, mem);
-        return;
 }
 
-static void
-pnpacpi_parse_mem32_option(struct pnp_option *option,
-        struct acpi_resource_memory32 *p)
+static void pnpacpi_parse_mem32_option(struct pnp_option *option,
+                                       struct acpi_resource_memory32 *p)
 {
         struct pnp_mem *mem;
 
@@ -494,15 +490,13 @@ pnpacpi_parse_mem32_option(struct pnp_option *option,
         mem->size = p->address_length;
 
         mem->flags = (ACPI_READ_WRITE_MEMORY == p->write_protect) ?
-                        IORESOURCE_MEM_WRITEABLE : 0;
+            IORESOURCE_MEM_WRITEABLE : 0;
 
         pnp_register_mem_resource(option, mem);
-        return;
 }
 
-static void
-pnpacpi_parse_fixed_mem32_option(struct pnp_option *option,
-        struct acpi_resource_fixed_memory32 *p)
+static void pnpacpi_parse_fixed_mem32_option(struct pnp_option *option,
+                                         struct acpi_resource_fixed_memory32 *p)
 {
         struct pnp_mem *mem;
 
@@ -516,14 +510,13 @@ pnpacpi_parse_fixed_mem32_option(struct pnp_option *option,
         mem->align = 0;
 
         mem->flags = (ACPI_READ_WRITE_MEMORY == p->write_protect) ?
-                        IORESOURCE_MEM_WRITEABLE : 0;
+            IORESOURCE_MEM_WRITEABLE : 0;
 
         pnp_register_mem_resource(option, mem);
-        return;
 }
 
-static void
-pnpacpi_parse_address_option(struct pnp_option *option, struct acpi_resource *r)
+static void pnpacpi_parse_address_option(struct pnp_option *option,
+                                         struct acpi_resource *r)
 {
         struct acpi_resource_address64 addr, *p = &addr;
         acpi_status status;
@@ -532,7 +525,8 @@ pnpacpi_parse_address_option(struct pnp_option *option, struct acpi_resource *r)
 
         status = acpi_resource_to_address64(r, p);
         if (!ACPI_SUCCESS(status)) {
-                pnp_warn("PnPACPI: failed to convert resource type %d", r->type);
+                pnp_warn("PnPACPI: failed to convert resource type %d",
+                         r->type);
                 return;
         }
 
@@ -547,7 +541,8 @@ pnpacpi_parse_address_option(struct pnp_option *option, struct acpi_resource *r)
                 mem->size = p->address_length;
                 mem->align = 0;
                 mem->flags = (p->info.mem.write_protect ==
-                    ACPI_READ_WRITE_MEMORY) ? IORESOURCE_MEM_WRITEABLE : 0;
+                              ACPI_READ_WRITE_MEMORY) ? IORESOURCE_MEM_WRITEABLE
+                    : 0;
                 pnp_register_mem_resource(option, mem);
         } else if (p->resource_type == ACPI_IO_RANGE) {
                 port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
@@ -568,109 +563,108 @@ struct acpipnp_parse_option_s {
 };
 
 static acpi_status pnpacpi_option_resource(struct acpi_resource *res,
-        void *data)
+                                           void *data)
 {
         int priority = 0;
-        struct acpipnp_parse_option_s *parse_data = (struct acpipnp_parse_option_s *)data;
+        struct acpipnp_parse_option_s *parse_data =
+            (struct acpipnp_parse_option_s *)data;
         struct pnp_dev *dev = parse_data->dev;
         struct pnp_option *option = parse_data->option;
 
         switch (res->type) {
-                case ACPI_RESOURCE_TYPE_IRQ:
-                        pnpacpi_parse_irq_option(option, &res->data.irq);
-                        break;
+        case ACPI_RESOURCE_TYPE_IRQ:
+                pnpacpi_parse_irq_option(option, &res->data.irq);
+                break;
 
-                case ACPI_RESOURCE_TYPE_DMA:
-                        pnpacpi_parse_dma_option(option, &res->data.dma);
-                        break;
+        case ACPI_RESOURCE_TYPE_DMA:
+                pnpacpi_parse_dma_option(option, &res->data.dma);
+                break;
 
-                case ACPI_RESOURCE_TYPE_START_DEPENDENT:
-                        switch (res->data.start_dpf.compatibility_priority) {
-                                case ACPI_GOOD_CONFIGURATION:
-                                        priority = PNP_RES_PRIORITY_PREFERRED;
-                                        break;
-
-                                case ACPI_ACCEPTABLE_CONFIGURATION:
-                                        priority = PNP_RES_PRIORITY_ACCEPTABLE;
-                                        break;
-
-                                case ACPI_SUB_OPTIMAL_CONFIGURATION:
-                                        priority = PNP_RES_PRIORITY_FUNCTIONAL;
-                                        break;
-                                default:
-                                        priority = PNP_RES_PRIORITY_INVALID;
-                                        break;
-                        }
-                        /* TBD: Considering performace/robustness bits */
-                        option = pnp_register_dependent_option(dev, priority);
-                        if (!option)
-                                return AE_ERROR;
-                        parse_data->option = option;
+        case ACPI_RESOURCE_TYPE_START_DEPENDENT:
+                switch (res->data.start_dpf.compatibility_priority) {
+                case ACPI_GOOD_CONFIGURATION:
+                        priority = PNP_RES_PRIORITY_PREFERRED;
                         break;
 
-                case ACPI_RESOURCE_TYPE_END_DEPENDENT:
-                        /*only one EndDependentFn is allowed*/
-                        if (!parse_data->option_independent) {
-                                pnp_warn("PnPACPI: more than one EndDependentFn");
-                                return AE_ERROR;
-                        }
-                        parse_data->option = parse_data->option_independent;
-                        parse_data->option_independent = NULL;
+                case ACPI_ACCEPTABLE_CONFIGURATION:
+                        priority = PNP_RES_PRIORITY_ACCEPTABLE;
                         break;
 
-                case ACPI_RESOURCE_TYPE_IO:
-                        pnpacpi_parse_port_option(option, &res->data.io);
+                case ACPI_SUB_OPTIMAL_CONFIGURATION:
+                        priority = PNP_RES_PRIORITY_FUNCTIONAL;
                         break;
-
-                case ACPI_RESOURCE_TYPE_FIXED_IO:
-                        pnpacpi_parse_fixed_port_option(option,
-                                &res->data.fixed_io);
+                default:
+                        priority = PNP_RES_PRIORITY_INVALID;
                         break;
+                }
+                /* TBD: Consider performance/robustness bits */
+                option = pnp_register_dependent_option(dev, priority);
+                if (!option)
+                        return AE_ERROR;
+                parse_data->option = option;
+                break;
 
-                case ACPI_RESOURCE_TYPE_VENDOR:
-                case ACPI_RESOURCE_TYPE_END_TAG:
-                        break;
+        case ACPI_RESOURCE_TYPE_END_DEPENDENT:
+                /*only one EndDependentFn is allowed */
+                if (!parse_data->option_independent) {
+                        pnp_warn("PnPACPI: more than one EndDependentFn");
+                        return AE_ERROR;
+                }
+                parse_data->option = parse_data->option_independent;
+                parse_data->option_independent = NULL;
+                break;
 
-                case ACPI_RESOURCE_TYPE_MEMORY24:
-                        pnpacpi_parse_mem24_option(option, &res->data.memory24);
-                        break;
+        case ACPI_RESOURCE_TYPE_IO:
+                pnpacpi_parse_port_option(option, &res->data.io);
+                break;
 
-                case ACPI_RESOURCE_TYPE_MEMORY32:
-                        pnpacpi_parse_mem32_option(option, &res->data.memory32);
-                        break;
+        case ACPI_RESOURCE_TYPE_FIXED_IO:
+                pnpacpi_parse_fixed_port_option(option, &res->data.fixed_io);
+                break;
 
-                case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
-                        pnpacpi_parse_fixed_mem32_option(option,
-                                &res->data.fixed_memory32);
-                        break;
+        case ACPI_RESOURCE_TYPE_VENDOR:
+        case ACPI_RESOURCE_TYPE_END_TAG:
+                break;
 
-                case ACPI_RESOURCE_TYPE_ADDRESS16:
-                case ACPI_RESOURCE_TYPE_ADDRESS32:
-                case ACPI_RESOURCE_TYPE_ADDRESS64:
-                        pnpacpi_parse_address_option(option, res);
-                        break;
+        case ACPI_RESOURCE_TYPE_MEMORY24:
+                pnpacpi_parse_mem24_option(option, &res->data.memory24);
+                break;
 
-                case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
-                        break;
+        case ACPI_RESOURCE_TYPE_MEMORY32:
+                pnpacpi_parse_mem32_option(option, &res->data.memory32);
+                break;
 
-                case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
-                        pnpacpi_parse_ext_irq_option(option,
-                                &res->data.extended_irq);
-                        break;
+        case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
+                pnpacpi_parse_fixed_mem32_option(option,
+                                                 &res->data.fixed_memory32);
+                break;
 
-                case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
-                        break;
+        case ACPI_RESOURCE_TYPE_ADDRESS16:
+        case ACPI_RESOURCE_TYPE_ADDRESS32:
+        case ACPI_RESOURCE_TYPE_ADDRESS64:
+                pnpacpi_parse_address_option(option, res);
+                break;
 
-                default:
-                        pnp_warn("PnPACPI: unknown resource type %d", res->type);
-                        return AE_ERROR;
+        case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
+                break;
+
+        case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+                pnpacpi_parse_ext_irq_option(option, &res->data.extended_irq);
+                break;
+
+        case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
+                break;
+
+        default:
+                pnp_warn("PnPACPI: unknown resource type %d", res->type);
+                return AE_ERROR;
         }
 
         return AE_OK;
 }
 
 acpi_status pnpacpi_parse_resource_option_data(acpi_handle handle,
-        struct pnp_dev *dev)
+                                               struct pnp_dev * dev)
 {
         acpi_status status;
         struct acpipnp_parse_option_s parse_data;
@@ -681,7 +675,7 @@ acpi_status pnpacpi_parse_resource_option_data(acpi_handle handle,
         parse_data.option_independent = parse_data.option;
         parse_data.dev = dev;
         status = acpi_walk_resources(handle, METHOD_NAME__PRS,
-                pnpacpi_option_resource, &parse_data);
+                                     pnpacpi_option_resource, &parse_data);
 
         return status;
 }
@@ -709,7 +703,7 @@ static int pnpacpi_supported_resource(struct acpi_resource *res)
  * Set resource
  */
 static acpi_status pnpacpi_count_resources(struct acpi_resource *res,
-        void *data)
+                                           void *data)
 {
         int *res_cnt = (int *)data;
 
@@ -732,14 +726,14 @@ static acpi_status pnpacpi_type_resources(struct acpi_resource *res, void *data)
 }
 
 int pnpacpi_build_resource_template(acpi_handle handle,
-        struct acpi_buffer *buffer)
+                                    struct acpi_buffer *buffer)
 {
         struct acpi_resource *resource;
         int res_cnt = 0;
         acpi_status status;
 
         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
-                pnpacpi_count_resources, &res_cnt);
+                                     pnpacpi_count_resources, &res_cnt);
         if (ACPI_FAILURE(status)) {
                 pnp_err("Evaluate _CRS failed");
                 return -EINVAL;
@@ -753,7 +747,7 @@ int pnpacpi_build_resource_template(acpi_handle handle,
         pnp_dbg("Res cnt %d", res_cnt);
         resource = (struct acpi_resource *)buffer->pointer;
         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
-                pnpacpi_type_resources, &resource);
+                                     pnpacpi_type_resources, &resource);
         if (ACPI_FAILURE(status)) {
                 kfree(buffer->pointer);
                 pnp_err("Evaluate _CRS failed");
@@ -766,7 +760,7 @@ int pnpacpi_build_resource_template(acpi_handle handle,
 }
 
 static void pnpacpi_encode_irq(struct acpi_resource *resource,
-        struct resource *p)
+                               struct resource *p)
 {
         int triggering, polarity;
 
@@ -782,7 +776,7 @@ static void pnpacpi_encode_irq(struct acpi_resource *resource,
 }
 
 static void pnpacpi_encode_ext_irq(struct acpi_resource *resource,
-        struct resource *p)
+                                   struct resource *p)
 {
         int triggering, polarity;
 
@@ -799,32 +793,32 @@ static void pnpacpi_encode_ext_irq(struct acpi_resource *resource,
 }
 
 static void pnpacpi_encode_dma(struct acpi_resource *resource,
-        struct resource *p)
+                               struct resource *p)
 {
         /* Note: pnp_assign_dma will copy pnp_dma->flags into p->flags */
         switch (p->flags & IORESOURCE_DMA_SPEED_MASK) {
-                case IORESOURCE_DMA_TYPEA:
-                        resource->data.dma.type = ACPI_TYPE_A;
-                        break;
-                case IORESOURCE_DMA_TYPEB:
-                        resource->data.dma.type = ACPI_TYPE_B;
-                        break;
-                case IORESOURCE_DMA_TYPEF:
-                        resource->data.dma.type = ACPI_TYPE_F;
-                        break;
-                default:
-                        resource->data.dma.type = ACPI_COMPATIBILITY;
+        case IORESOURCE_DMA_TYPEA:
+                resource->data.dma.type = ACPI_TYPE_A;
+                break;
+        case IORESOURCE_DMA_TYPEB:
+                resource->data.dma.type = ACPI_TYPE_B;
+                break;
+        case IORESOURCE_DMA_TYPEF:
+                resource->data.dma.type = ACPI_TYPE_F;
+                break;
+        default:
+                resource->data.dma.type = ACPI_COMPATIBILITY;
         }
 
         switch (p->flags & IORESOURCE_DMA_TYPE_MASK) {
-                case IORESOURCE_DMA_8BIT:
-                        resource->data.dma.transfer = ACPI_TRANSFER_8;
-                        break;
-                case IORESOURCE_DMA_8AND16BIT:
-                        resource->data.dma.transfer = ACPI_TRANSFER_8_16;
-                        break;
-                default:
-                        resource->data.dma.transfer = ACPI_TRANSFER_16;
+        case IORESOURCE_DMA_8BIT:
+                resource->data.dma.transfer = ACPI_TRANSFER_8;
+                break;
+        case IORESOURCE_DMA_8AND16BIT:
+                resource->data.dma.transfer = ACPI_TRANSFER_8_16;
+                break;
+        default:
+                resource->data.dma.transfer = ACPI_TRANSFER_16;
         }
 
         resource->data.dma.bus_master = !!(p->flags & IORESOURCE_DMA_MASTER);
@@ -833,31 +827,31 @@ static void pnpacpi_encode_dma(struct acpi_resource *resource,
 }
 
 static void pnpacpi_encode_io(struct acpi_resource *resource,
-        struct resource *p)
+                              struct resource *p)
 {
         /* Note: pnp_assign_port will copy pnp_port->flags into p->flags */
-        resource->data.io.io_decode = (p->flags & PNP_PORT_FLAG_16BITADDR)?
-                ACPI_DECODE_16 : ACPI_DECODE_10;
+        resource->data.io.io_decode = (p->flags & PNP_PORT_FLAG_16BITADDR) ?
+            ACPI_DECODE_16 : ACPI_DECODE_10;
         resource->data.io.minimum = p->start;
         resource->data.io.maximum = p->end;
-        resource->data.io.alignment = 0; /* Correct? */
+        resource->data.io.alignment = 0;        /* Correct? */
         resource->data.io.address_length = p->end - p->start + 1;
 }
 
 static void pnpacpi_encode_fixed_io(struct acpi_resource *resource,
-        struct resource *p)
+                                    struct resource *p)
 {
         resource->data.fixed_io.address = p->start;
         resource->data.fixed_io.address_length = p->end - p->start + 1;
 }
 
 static void pnpacpi_encode_mem24(struct acpi_resource *resource,
-        struct resource *p)
+                                 struct resource *p)
 {
         /* Note: pnp_assign_mem will copy pnp_mem->flags into p->flags */
         resource->data.memory24.write_protect =
-                (p->flags & IORESOURCE_MEM_WRITEABLE) ?
-                ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
+            (p->flags & IORESOURCE_MEM_WRITEABLE) ?
+            ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
         resource->data.memory24.minimum = p->start;
         resource->data.memory24.maximum = p->end;
         resource->data.memory24.alignment = 0;
@@ -865,11 +859,11 @@ static void pnpacpi_encode_mem24(struct acpi_resource *resource,
 }
 
 static void pnpacpi_encode_mem32(struct acpi_resource *resource,
-        struct resource *p)
+                                 struct resource *p)
 {
         resource->data.memory32.write_protect =
-                (p->flags & IORESOURCE_MEM_WRITEABLE) ?
-                ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
+            (p->flags & IORESOURCE_MEM_WRITEABLE) ?
+            ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
         resource->data.memory32.minimum = p->start;
         resource->data.memory32.maximum = p->end;
         resource->data.memory32.alignment = 0;
@@ -877,74 +871,77 @@ static void pnpacpi_encode_mem32(struct acpi_resource *resource,
 }
 
 static void pnpacpi_encode_fixed_mem32(struct acpi_resource *resource,
-        struct resource *p)
+                                       struct resource *p)
 {
         resource->data.fixed_memory32.write_protect =
-                (p->flags & IORESOURCE_MEM_WRITEABLE) ?
-                ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
+            (p->flags & IORESOURCE_MEM_WRITEABLE) ?
+            ACPI_READ_WRITE_MEMORY : ACPI_READ_ONLY_MEMORY;
         resource->data.fixed_memory32.address = p->start;
         resource->data.fixed_memory32.address_length = p->end - p->start + 1;
 }
 
 int pnpacpi_encode_resources(struct pnp_resource_table *res_table,
-        struct acpi_buffer *buffer)
+                             struct acpi_buffer *buffer)
 {
         int i = 0;
         /* pnpacpi_build_resource_template allocates extra mem */
-        int res_cnt = (buffer->length - 1)/sizeof(struct acpi_resource) - 1;
-        struct acpi_resource *resource = (struct acpi_resource*)buffer->pointer;
+        int res_cnt = (buffer->length - 1) / sizeof(struct acpi_resource) - 1;
+        struct acpi_resource *resource =
+            (struct acpi_resource *)buffer->pointer;
         int port = 0, irq = 0, dma = 0, mem = 0;
 
         pnp_dbg("res cnt %d", res_cnt);
         while (i < res_cnt) {
-                switch(resource->type) {
+                switch (resource->type) {
                 case ACPI_RESOURCE_TYPE_IRQ:
                         pnp_dbg("Encode irq");
                         pnpacpi_encode_irq(resource,
-                                &res_table->irq_resource[irq]);
+                                           &res_table->irq_resource[irq]);
                         irq++;
                         break;
 
                 case ACPI_RESOURCE_TYPE_DMA:
                         pnp_dbg("Encode dma");
                         pnpacpi_encode_dma(resource,
-                                &res_table->dma_resource[dma]);
+                                           &res_table->dma_resource[dma]);
                         dma++;
                         break;
                 case ACPI_RESOURCE_TYPE_IO:
                         pnp_dbg("Encode io");
                         pnpacpi_encode_io(resource,
-                                &res_table->port_resource[port]);
+                                          &res_table->port_resource[port]);
                         port++;
                         break;
                 case ACPI_RESOURCE_TYPE_FIXED_IO:
                         pnp_dbg("Encode fixed io");
                         pnpacpi_encode_fixed_io(resource,
-                                &res_table->port_resource[port]);
+                                                &res_table->
+                                                port_resource[port]);
                         port++;
                         break;
                 case ACPI_RESOURCE_TYPE_MEMORY24:
                         pnp_dbg("Encode mem24");
                         pnpacpi_encode_mem24(resource,
-                                &res_table->mem_resource[mem]);
+                                             &res_table->mem_resource[mem]);
                         mem++;
                         break;
                 case ACPI_RESOURCE_TYPE_MEMORY32:
                         pnp_dbg("Encode mem32");
                         pnpacpi_encode_mem32(resource,
-                                &res_table->mem_resource[mem]);
+                                             &res_table->mem_resource[mem]);
                         mem++;
                         break;
                 case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
                         pnp_dbg("Encode fixed mem32");
                         pnpacpi_encode_fixed_mem32(resource,
-                                &res_table->mem_resource[mem]);
+                                                   &res_table->
+                                                   mem_resource[mem]);
                         mem++;
                         break;
                 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
                         pnp_dbg("Encode ext irq");
                         pnpacpi_encode_ext_irq(resource,
-                                &res_table->irq_resource[irq]);
+                                               &res_table->irq_resource[irq]);
                         irq++;
                         break;
                 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
@@ -956,7 +953,7 @@ int pnpacpi_encode_resources(struct pnp_resource_table *res_table,
                 case ACPI_RESOURCE_TYPE_ADDRESS64:
                 case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
                 case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
-                default: /* other type */
+                default:        /* other type */
                         pnp_warn("unknown resource type %d", resource->type);
                         return -EINVAL;
                 }
diff --git a/drivers/pnp/pnpbios/bioscalls.c b/drivers/pnp/pnpbios/bioscalls.c
index a1f0b0ba2bfe..5dba68fe33f5 100644
--- a/drivers/pnp/pnpbios/bioscalls.c
+++ b/drivers/pnp/pnpbios/bioscalls.c
@@ -1,6 +1,5 @@
 /*
  * bioscalls.c - the lowlevel layer of the PnPBIOS driver
- *
  */
 
 #include <linux/types.h>
@@ -26,11 +25,10 @@
 #include "pnpbios.h"
 
 static struct {
-        u16     offset;
-        u16     segment;
+        u16 offset;
+        u16 segment;
 } pnp_bios_callpoint;
 
-
 /*
  * These are some opcodes for a "static asmlinkage"
  * As this code is *not* executed inside the linux kernel segment, but in a
@@ -44,8 +42,7 @@ static struct {
 
 asmlinkage void pnp_bios_callfunc(void);
 
-__asm__(
-        ".text                  \n"
+__asm__(".text                  \n"
         __ALIGN_STR "\n"
         "pnp_bios_callfunc:\n"
         "       pushl %edx      \n"
@@ -55,8 +52,7 @@ __asm__(
         "       lcallw *pnp_bios_callpoint\n"
         "       addl $16, %esp  \n"
         "       lret            \n"
-        ".previous              \n"
-);
+        ".previous              \n");
 
 #define Q2_SET_SEL(cpu, selname, address, size) \
 do { \
@@ -78,7 +74,6 @@ u32 pnp_bios_is_utter_crap = 0;
 
 static spinlock_t pnp_bios_lock;
 
-
 /*
  * Support Functions
  */
@@ -97,7 +92,7 @@ static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
          * PnP BIOSes are generally not terribly re-entrant.
          * Also, don't rely on them to save everything correctly.
          */
-        if(pnp_bios_is_utter_crap)
+        if (pnp_bios_is_utter_crap)
                 return PNP_FUNCTION_NOT_SUPPORTED;
 
         cpu = get_cpu();
@@ -113,112 +108,128 @@ static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
         if (ts2_size)
                 Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
 
-        __asm__ __volatile__(
-                "pushl %%ebp\n\t"
-                "pushl %%edi\n\t"
-                "pushl %%esi\n\t"
-                "pushl %%ds\n\t"
-                "pushl %%es\n\t"
-                "pushl %%fs\n\t"
-                "pushl %%gs\n\t"
-                "pushfl\n\t"
-                "movl %%esp, pnp_bios_fault_esp\n\t"
-                "movl $1f, pnp_bios_fault_eip\n\t"
-                "lcall %5,%6\n\t"
-                "1:popfl\n\t"
-                "popl %%gs\n\t"
-                "popl %%fs\n\t"
-                "popl %%es\n\t"
-                "popl %%ds\n\t"
-                "popl %%esi\n\t"
-                "popl %%edi\n\t"
-                "popl %%ebp\n\t"
-                : "=a" (status)
-                : "0" ((func) | (((u32)arg1) << 16)),
-                  "b" ((arg2) | (((u32)arg3) << 16)),
-                  "c" ((arg4) | (((u32)arg5) << 16)),
-                  "d" ((arg6) | (((u32)arg7) << 16)),
-                  "i" (PNP_CS32),
-                  "i" (0)
-                : "memory"
-        );
+        __asm__ __volatile__("pushl %%ebp\n\t"
+                             "pushl %%edi\n\t"
+                             "pushl %%esi\n\t"
+                             "pushl %%ds\n\t"
+                             "pushl %%es\n\t"
+                             "pushl %%fs\n\t"
+                             "pushl %%gs\n\t"
+                             "pushfl\n\t"
+                             "movl %%esp, pnp_bios_fault_esp\n\t"
+                             "movl $1f, pnp_bios_fault_eip\n\t"
+                             "lcall %5,%6\n\t"
+                             "1:popfl\n\t"
+                             "popl %%gs\n\t"
+                             "popl %%fs\n\t"
+                             "popl %%es\n\t"
+                             "popl %%ds\n\t"
+                             "popl %%esi\n\t"
+                             "popl %%edi\n\t"
+                             "popl %%ebp\n\t":"=a"(status)
+                             :"0"((func) | (((u32) arg1) << 16)),
+                             "b"((arg2) | (((u32) arg3) << 16)),
+                             "c"((arg4) | (((u32) arg5) << 16)),
+                             "d"((arg6) | (((u32) arg7) << 16)),
+                             "i"(PNP_CS32), "i"(0)
+                             :"memory");
         spin_unlock_irqrestore(&pnp_bios_lock, flags);
 
         get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
         put_cpu();
 
         /* If we get here and this is set then the PnP BIOS faulted on us. */
-        if(pnp_bios_is_utter_crap)
-        {
-                printk(KERN_ERR "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
-                printk(KERN_ERR "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
-                printk(KERN_ERR "PnPBIOS: Check with your vendor for an updated BIOS\n");
+        if (pnp_bios_is_utter_crap) {
+                printk(KERN_ERR
+                       "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
+                printk(KERN_ERR
+                       "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
+                printk(KERN_ERR
+                       "PnPBIOS: Check with your vendor for an updated BIOS\n");
         }
 
         return status;
 }
 
-void pnpbios_print_status(const char * module, u16 status)
+void pnpbios_print_status(const char *module, u16 status)
 {
-        switch(status) {
+        switch (status) {
         case PNP_SUCCESS:
                 printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
                 break;
         case PNP_NOT_SET_STATICALLY:
-                printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n",
+                       module);
                 break;
         case PNP_UNKNOWN_FUNCTION:
-                printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n",
+                       module);
                 break;
         case PNP_FUNCTION_NOT_SUPPORTED:
-                printk(KERN_ERR "PnPBIOS: %s: function not supported on this system\n", module);
+                printk(KERN_ERR
+                       "PnPBIOS: %s: function not supported on this system\n",
+                       module);
                 break;
         case PNP_INVALID_HANDLE:
                 printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
                 break;
         case PNP_BAD_PARAMETER:
-                printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n",
+                       module);
                 break;
         case PNP_SET_FAILED:
-                printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n",
+                       module);
                 break;
         case PNP_EVENTS_NOT_PENDING:
                 printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
                 break;
         case PNP_SYSTEM_NOT_DOCKED:
-                printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n",
+                       module);
                 break;
         case PNP_NO_ISA_PNP_CARDS:
-                printk(KERN_ERR "PnPBIOS: %s: no isapnp cards are installed on this system\n", module);
+                printk(KERN_ERR
+                       "PnPBIOS: %s: no isapnp cards are installed on this system\n",
+                       module);
                 break;
         case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
-                printk(KERN_ERR "PnPBIOS: %s: cannot determine the capabilities of the docking station\n", module);
+                printk(KERN_ERR
+                       "PnPBIOS: %s: cannot determine the capabilities of the docking station\n",
+                       module);
                 break;
         case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
-                printk(KERN_ERR "PnPBIOS: %s: unable to undock, the system does not have a battery\n", module);
+                printk(KERN_ERR
+                       "PnPBIOS: %s: unable to undock, the system does not have a battery\n",
+                       module);
                 break;
         case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
-                printk(KERN_ERR "PnPBIOS: %s: could not dock due to resource conflicts\n", module);
+                printk(KERN_ERR
+                       "PnPBIOS: %s: could not dock due to resource conflicts\n",
+                       module);
                 break;
         case PNP_BUFFER_TOO_SMALL:
-                printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n",
+                       module);
                 break;
         case PNP_USE_ESCD_SUPPORT:
                 printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
                 break;
         case PNP_MESSAGE_NOT_SUPPORTED:
-                printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n",
+                       module);
                 break;
         case PNP_HARDWARE_ERROR:
-                printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n", module);
+                printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n",
+                       module);
                 break;
         default:
-                printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module, status);
+                printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module,
+                       status);
                 break;
         }
 }
 
-
 /*
  * PnP BIOS Low Level Calls
  */
@@ -243,19 +254,22 @@ void pnpbios_print_status(const char * module, u16 status)
 static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2, PNP_TS1, PNP_DS, 0, 0,
-                               data, sizeof(struct pnp_dev_node_info), NULL, 0);
+        status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2,
+                               PNP_TS1, PNP_DS, 0, 0, data,
+                               sizeof(struct pnp_dev_node_info), NULL, 0);
         data->no_nodes &= 0xff;
         return status;
 }
 
 int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 {
-        int status = __pnp_bios_dev_node_info( data );
-        if ( status )
-                pnpbios_print_status( "dev_node_info", status );
+        int status = __pnp_bios_dev_node_info(data);
+
+        if (status)
+                pnpbios_print_status("dev_node_info", status);
         return status;
 }
 
@@ -273,17 +287,20 @@ int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
  *               or volatile current (0) config
  * Output: *nodenum=next node or 0xff if no more nodes
  */
-static int __pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
+static int __pnp_bios_get_dev_node(u8 *nodenum, char boot,
+                                   struct pnp_bios_node *data)
 {
         u16 status;
         u16 tmp_nodenum;
+
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        if ( !boot && pnpbios_dont_use_current_config )
+        if (!boot && pnpbios_dont_use_current_config)
                 return PNP_FUNCTION_NOT_SUPPORTED;
         tmp_nodenum = *nodenum;
-        status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2, boot ? 2 : 1, PNP_DS, 0,
-                               &tmp_nodenum, sizeof(tmp_nodenum), data, 65536);
+        status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2,
+                               boot ? 2 : 1, PNP_DS, 0, &tmp_nodenum,
+                               sizeof(tmp_nodenum), data, 65536);
         *nodenum = tmp_nodenum;
         return status;
 }
@@ -291,104 +308,66 @@ static int __pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node
 int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
 {
         int status;
-        status =  __pnp_bios_get_dev_node( nodenum, boot, data );
-        if ( status )
-                pnpbios_print_status( "get_dev_node", status );
+
+        status = __pnp_bios_get_dev_node(nodenum, boot, data);
+        if (status)
+                pnpbios_print_status("get_dev_node", status);
         return status;
 }
 
-
 /*
  * Call PnP BIOS with function 0x02, "set system device node"
  * Input: *nodenum = desired node, 
  *        boot = whether to set nonvolatile boot (!=0)
  *               or volatile current (0) config
  */
-static int __pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
+static int __pnp_bios_set_dev_node(u8 nodenum, char boot,
+                                   struct pnp_bios_node *data)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        if ( !boot && pnpbios_dont_use_current_config )
+        if (!boot && pnpbios_dont_use_current_config)
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1, boot ? 2 : 1, PNP_DS, 0, 0,
-                               data, 65536, NULL, 0);
+        status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1,
+                               boot ? 2 : 1, PNP_DS, 0, 0, data, 65536, NULL,
+                               0);
         return status;
 }
 
 int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
 {
         int status;
-        status =  __pnp_bios_set_dev_node( nodenum, boot, data );
-        if ( status ) {
-                pnpbios_print_status( "set_dev_node", status );
+
+        status = __pnp_bios_set_dev_node(nodenum, boot, data);
+        if (status) {
+                pnpbios_print_status("set_dev_node", status);
                 return status;
         }
-        if ( !boot ) { /* Update devlist */
-                status =  pnp_bios_get_dev_node( &nodenum, boot, data );
-                if ( status )
+        if (!boot) {            /* Update devlist */
+                status = pnp_bios_get_dev_node(&nodenum, boot, data);
+                if (status)
                         return status;
         }
         return status;
 }
 
-#if needed
-/*
- * Call PnP BIOS with function 0x03, "get event"
- */
-static int pnp_bios_get_event(u16 *event)
-{
-        u16 status;
-        if (!pnp_bios_present())
-                return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_EVENT, 0, PNP_TS1, PNP_DS, 0, 0 ,0 ,0,
-                               event, sizeof(u16), NULL, 0);
-        return status;
-}
-#endif
-
-#if needed
-/*
- * Call PnP BIOS with function 0x04, "send message"
- */
-static int pnp_bios_send_message(u16 message)
-{
-        u16 status;
-        if (!pnp_bios_present())
-                return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_SEND_MESSAGE, message, PNP_DS, 0, 0, 0, 0, 0, 0, 0, 0, 0);
-        return status;
-}
-#endif
-
 /*
  * Call PnP BIOS with function 0x05, "get docking station information"
  */
 int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
 {
         u16 status;
-        if (!pnp_bios_present())
-                return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
-                               data, sizeof(struct pnp_docking_station_info), NULL, 0);
-        return status;
-}
 
-#if needed
-/*
- * Call PnP BIOS with function 0x09, "set statically allocated resource
- * information"
- */
-static int pnp_bios_set_stat_res(char *info)
-{
-        u16 status;
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_SET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
-                               info, *((u16 *) info), 0, 0);
+        status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1,
+                               PNP_DS, 0, 0, 0, 0, data,
+                               sizeof(struct pnp_docking_station_info), NULL,
+                               0);
         return status;
 }
-#endif
 
 /*
  * Call PnP BIOS with function 0x0a, "get statically allocated resource
@@ -397,36 +376,23 @@ static int pnp_bios_set_stat_res(char *info)
 static int __pnp_bios_get_stat_res(char *info)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
-                               info, 65536, NULL, 0);
+        status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1,
+                               PNP_DS, 0, 0, 0, 0, info, 65536, NULL, 0);
         return status;
 }
 
 int pnp_bios_get_stat_res(char *info)
 {
         int status;
-        status = __pnp_bios_get_stat_res( info );
-        if ( status )
-                pnpbios_print_status( "get_stat_res", status );
-        return status;
-}
 
-#if needed
-/*
- * Call PnP BIOS with function 0x0b, "get APM id table"
- */
-static int pnp_bios_apm_id_table(char *table, u16 *size)
-{
-        u16 status;
-        if (!pnp_bios_present())
-                return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_APM_ID_TABLE, 0, PNP_TS2, 0, PNP_TS1, PNP_DS, 0, 0,
-                               table, *size, size, sizeof(u16));
+        status = __pnp_bios_get_stat_res(info);
+        if (status)
+                pnpbios_print_status("get_stat_res", status);
         return status;
 }
-#endif
 
 /*
  * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
@@ -434,19 +400,22 @@ static int pnp_bios_apm_id_table(char *table, u16 *size)
 static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return PNP_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
-                               data, sizeof(struct pnp_isa_config_struc), NULL, 0);
+        status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS,
+                               0, 0, 0, 0, data,
+                               sizeof(struct pnp_isa_config_struc), NULL, 0);
         return status;
 }
 
 int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 {
         int status;
-        status = __pnp_bios_isapnp_config( data );
-        if ( status )
-                pnpbios_print_status( "isapnp_config", status );
+
+        status = __pnp_bios_isapnp_config(data);
+        if (status)
+                pnpbios_print_status("isapnp_config", status);
         return status;
 }
 
@@ -456,19 +425,22 @@ int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 static int __pnp_bios_escd_info(struct escd_info_struc *data)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return ESCD_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4, PNP_TS1, PNP_DS,
-                               data, sizeof(struct escd_info_struc), NULL, 0);
+        status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4,
+                               PNP_TS1, PNP_DS, data,
+                               sizeof(struct escd_info_struc), NULL, 0);
         return status;
 }
 
 int pnp_bios_escd_info(struct escd_info_struc *data)
 {
         int status;
-        status = __pnp_bios_escd_info( data );
-        if ( status )
-                pnpbios_print_status( "escd_info", status );
+
+        status = __pnp_bios_escd_info(data);
+        if (status)
+                pnpbios_print_status("escd_info", status);
         return status;
 }
 
@@ -479,57 +451,42 @@ int pnp_bios_escd_info(struct escd_info_struc *data)
 static int __pnp_bios_read_escd(char *data, u32 nvram_base)
 {
         u16 status;
+
         if (!pnp_bios_present())
                 return ESCD_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
-                               data, 65536, __va(nvram_base), 65536);
+        status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0,
+                               0, data, 65536, __va(nvram_base), 65536);
         return status;
 }
 
 int pnp_bios_read_escd(char *data, u32 nvram_base)
 {
         int status;
-        status = __pnp_bios_read_escd( data, nvram_base );
-        if ( status )
-                pnpbios_print_status( "read_escd", status );
-        return status;
-}
 
-#if needed
-/*
- * Call PnP BIOS function 0x43, "write ESCD"
- */
-static int pnp_bios_write_escd(char *data, u32 nvram_base)
-{
-        u16 status;
-        if (!pnp_bios_present())
-                return ESCD_FUNCTION_NOT_SUPPORTED;
-        status = call_pnp_bios(PNP_WRITE_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
-                               data, 65536, __va(nvram_base), 65536);
+        status = __pnp_bios_read_escd(data, nvram_base);
+        if (status)
+                pnpbios_print_status("read_escd", status);
         return status;
 }
-#endif
-
-
-/*
- * Initialization
- */
 
 void pnpbios_calls_init(union pnp_bios_install_struct *header)
 {
         int i;
+
         spin_lock_init(&pnp_bios_lock);
         pnp_bios_callpoint.offset = header->fields.pm16offset;
         pnp_bios_callpoint.segment = PNP_CS16;
 
         set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
         _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
-        for (i = 0; i < NR_CPUS; i++) {
-                struct desc_struct *gdt = get_cpu_gdt_table(i);
-                if (!gdt)
-                        continue;
-                set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);
-                set_base(gdt[GDT_ENTRY_PNPBIOS_CS16], __va(header->fields.pm16cseg));
-                set_base(gdt[GDT_ENTRY_PNPBIOS_DS], __va(header->fields.pm16dseg));
-        }
+        for (i = 0; i < NR_CPUS; i++) {
+                struct desc_struct *gdt = get_cpu_gdt_table(i);
+                if (!gdt)
+                        continue;
+                set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);
+                set_base(gdt[GDT_ENTRY_PNPBIOS_CS16],
+                         __va(header->fields.pm16cseg));
+                set_base(gdt[GDT_ENTRY_PNPBIOS_DS],
+                         __va(header->fields.pm16dseg));
+        }
 }
diff --git a/drivers/pnp/pnpbios/core.c b/drivers/pnp/pnpbios/core.c
index ed112ee16012..3692a099b45f 100644
--- a/drivers/pnp/pnpbios/core.c
+++ b/drivers/pnp/pnpbios/core.c
@@ -32,7 +32,7 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
- 
+
 /* Change Log
  *
  * Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
@@ -71,14 +71,13 @@
 
 #include "pnpbios.h"
 
-
 /*
  *
  * PnP BIOS INTERFACE
  *
  */
 
-static union pnp_bios_install_struct * pnp_bios_install = NULL;
+static union pnp_bios_install_struct *pnp_bios_install = NULL;
 
 int pnp_bios_present(void)
 {
@@ -101,36 +100,35 @@ static struct completion unload_sem;
 /*
  * (Much of this belongs in a shared routine somewhere)
  */
- 
 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 {
-        char *argv [3], **envp, *buf, *scratch;
+        char *argv[3], **envp, *buf, *scratch;
         int i = 0, value;
 
-        if (!current->fs->root) {
+        if (!current->fs->root)
                 return -EAGAIN;
-        }
-        if (!(envp = kcalloc(20, sizeof (char *), GFP_KERNEL))) {
+        if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
                 return -ENOMEM;
-        }
         if (!(buf = kzalloc(256, GFP_KERNEL))) {
-                kfree (envp);
+                kfree(envp);
                 return -ENOMEM;
         }
 
-        /* FIXME: if there are actual users of this, it should be integrated into
-         * the driver core and use the usual infrastructure like sysfs and uevents */
-        argv [0] = "/sbin/pnpbios";
-        argv [1] = "dock";
-        argv [2] = NULL;
+        /* FIXME: if there are actual users of this, it should be
+         * integrated into the driver core and use the usual infrastructure
+         * like sysfs and uevents
+         */
+        argv[0] = "/sbin/pnpbios";
+        argv[1] = "dock";
+        argv[2] = NULL;
 
         /* minimal command environment */
-        envp [i++] = "HOME=/";
-        envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+        envp[i++] = "HOME=/";
+        envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 
 #ifdef  DEBUG
         /* hint that policy agent should enter no-stdout debug mode */
-        envp [i++] = "DEBUG=kernel";
+        envp[i++] = "DEBUG=kernel";
 #endif
         /* extensible set of named bus-specific parameters,
          * supporting multiple driver selection algorithms.
@@ -138,33 +136,33 @@ static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
         scratch = buf;
 
         /* action:  add, remove */
-        envp [i++] = scratch;
-        scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;
+        envp[i++] = scratch;
+        scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
 
         /* Report the ident for the dock */
-        envp [i++] = scratch;
-        scratch += sprintf (scratch, "DOCK=%x/%x/%x",
-                info->location_id, info->serial, info->capabilities);
+        envp[i++] = scratch;
+        scratch += sprintf(scratch, "DOCK=%x/%x/%x",
+                           info->location_id, info->serial, info->capabilities);
         envp[i] = NULL;
-        
-        value = call_usermodehelper (argv [0], argv, envp, UMH_WAIT_EXEC);
-        kfree (buf);
-        kfree (envp);
+
+        value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
+        kfree(buf);
+        kfree(envp);
         return 0;
 }
 
 /*
  * Poll the PnP docking at regular intervals
  */
-static int pnp_dock_thread(void * unused)
+static int pnp_dock_thread(void *unused)
 {
         static struct pnp_docking_station_info now;
         int docked = -1, d = 0;
+
         set_freezable();
-        while (!unloading)
-        {
+        while (!unloading) {
                 int status;
-                
+
                 /*
                  * Poll every 2 seconds
                  */
@@ -175,30 +173,29 @@ static int pnp_dock_thread(void * unused)
 
                 status = pnp_bios_dock_station_info(&now);
 
-                switch(status)
-                {
+                switch (status) {
                         /*
                          * No dock to manage
                          */
-                        case PNP_FUNCTION_NOT_SUPPORTED:
-                                complete_and_exit(&unload_sem, 0);
-                        case PNP_SYSTEM_NOT_DOCKED:
-                                d = 0;
-                                break;
-                        case PNP_SUCCESS:
-                                d = 1;
-                                break;
-                        default:
-                                pnpbios_print_status( "pnp_dock_thread", status );
-                                continue;
+                case PNP_FUNCTION_NOT_SUPPORTED:
+                        complete_and_exit(&unload_sem, 0);
+                case PNP_SYSTEM_NOT_DOCKED:
+                        d = 0;
+                        break;
+                case PNP_SUCCESS:
+                        d = 1;
+                        break;
+                default:
+                        pnpbios_print_status("pnp_dock_thread", status);
+                        continue;
                 }
-                if(d != docked)
-                {
-                        if(pnp_dock_event(d, &now)==0)
-                        {
+                if (d != docked) {
+                        if (pnp_dock_event(d, &now) == 0) {
                                 docked = d;
 #if 0
-                                printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
+                                printk(KERN_INFO
+                                       "PnPBIOS: Docking station %stached\n",
+                                       docked ? "at" : "de");
 #endif
                         }
                 }
@@ -206,21 +203,21 @@ static int pnp_dock_thread(void * unused)
         complete_and_exit(&unload_sem, 0);
 }
 
-#endif   /* CONFIG_HOTPLUG */
+#endif                          /* CONFIG_HOTPLUG */
 
-static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
+static int pnpbios_get_resources(struct pnp_dev *dev,
+                                 struct pnp_resource_table *res)
 {
         u8 nodenum = dev->number;
-        struct pnp_bios_node * node;
+        struct pnp_bios_node *node;
 
-        /* just in case */
-        if(!pnpbios_is_dynamic(dev))
+        if (!pnpbios_is_dynamic(dev))
                 return -EPERM;
 
         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
         if (!node)
                 return -1;
-        if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
+        if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
                 kfree(node);
                 return -ENODEV;
         }
@@ -230,24 +227,24 @@ static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table
         return 0;
 }
 
-static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
+static int pnpbios_set_resources(struct pnp_dev *dev,
+                                 struct pnp_resource_table *res)
 {
         u8 nodenum = dev->number;
-        struct pnp_bios_node * node;
+        struct pnp_bios_node *node;
         int ret;
 
-        /* just in case */
         if (!pnpbios_is_dynamic(dev))
                 return -EPERM;
 
         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
         if (!node)
                 return -1;
-        if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
+        if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
                 kfree(node);
                 return -ENODEV;
         }
-        if(pnpbios_write_resources_to_node(res, node)<0) {
+        if (pnpbios_write_resources_to_node(res, node) < 0) {
                 kfree(node);
                 return -1;
         }
@@ -258,18 +255,19 @@ static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table
         return ret;
 }
 
-static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
+static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 {
-        unsigned char * p = (char *)node->data;
-        unsigned char * end = (char *)(node->data + node->size);
+        unsigned char *p = (char *)node->data;
+        unsigned char *end = (char *)(node->data + node->size);
         unsigned int len;
         int i;
+
         while ((char *)p < (char *)end) {
-                if(p[0] & 0x80) { /* large tag */
+                if (p[0] & 0x80) {      /* large tag */
                         len = (p[2] << 8) | p[1];
                         p += 3;
                 } else {
-                        if (((p[0]>>3) & 0x0f) == 0x0f)
+                        if (((p[0] >> 3) & 0x0f) == 0x0f)
                                 return;
                         len = p[0] & 0x07;
                         p += 1;
@@ -278,24 +276,24 @@ static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
                         p[i] = 0;
                 p += len;
         }
-        printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
+        printk(KERN_ERR
+               "PnPBIOS: Resource structure did not contain an end tag.\n");
 }
 
 static int pnpbios_disable_resources(struct pnp_dev *dev)
 {
-        struct pnp_bios_node * node;
+        struct pnp_bios_node *node;
         u8 nodenum = dev->number;
         int ret;
 
-        /* just in case */
-        if(dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
+        if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
                 return -EPERM;
 
         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
         if (!node)
                 return -ENOMEM;
 
-        if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
+        if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
                 kfree(node);
                 return -ENODEV;
         }
@@ -311,22 +309,22 @@ static int pnpbios_disable_resources(struct pnp_dev *dev)
 /* PnP Layer support */
 
 struct pnp_protocol pnpbios_protocol = {
-        .name   = "Plug and Play BIOS",
-        .get    = pnpbios_get_resources,
-        .set    = pnpbios_set_resources,
+        .name = "Plug and Play BIOS",
+        .get = pnpbios_get_resources,
+        .set = pnpbios_set_resources,
         .disable = pnpbios_disable_resources,
 };
 
-static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
+static int insert_device(struct pnp_dev *dev, struct pnp_bios_node *node)
 {
-        struct list_head * pos;
-        struct pnp_dev * pnp_dev;
+        struct list_head *pos;
+        struct pnp_dev *pnp_dev;
         struct pnp_id *dev_id;
         char id[8];
 
         /* check if the device is already added */
         dev->number = node->handle;
-        list_for_each (pos, &pnpbios_protocol.devices){
+        list_for_each(pos, &pnpbios_protocol.devices) {
                 pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
                 if (dev->number == pnp_dev->number)
                         return -1;
@@ -336,8 +334,8 @@ static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
         dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
         if (!dev_id)
                 return -1;
-        pnpid32_to_pnpid(node->eisa_id,id);
-        memcpy(dev_id->id,id,7);
+        pnpid32_to_pnpid(node->eisa_id, id);
+        memcpy(dev_id->id, id, 7);
         pnp_add_id(dev_id, dev);
         pnpbios_parse_data_stream(dev, node);
         dev->active = pnp_is_active(dev);
@@ -375,35 +373,41 @@ static void __init build_devlist(void)
         if (!node)
                 return;
 
-        for(nodenum=0; nodenum<0xff; ) {
+        for (nodenum = 0; nodenum < 0xff;) {
                 u8 thisnodenum = nodenum;
                 /* eventually we will want to use PNPMODE_STATIC here but for now
                  * dynamic will help us catch buggy bioses to add to the blacklist.
                  */
                 if (!pnpbios_dont_use_current_config) {
-                        if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
+                        if (pnp_bios_get_dev_node
+                            (&nodenum, (char)PNPMODE_DYNAMIC, node))
                                 break;
                 } else {
-                        if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
+                        if (pnp_bios_get_dev_node
+                            (&nodenum, (char)PNPMODE_STATIC, node))
                                 break;
                 }
                 nodes_got++;
-                dev =  kzalloc(sizeof (struct pnp_dev), GFP_KERNEL);
+                dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
                 if (!dev)
                         break;
-                if(insert_device(dev,node)<0)
+                if (insert_device(dev, node) < 0)
                         kfree(dev);
                 else
                         devs++;
                 if (nodenum <= thisnodenum) {
-                        printk(KERN_ERR "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n", (unsigned int)nodenum, (unsigned int)thisnodenum);
+                        printk(KERN_ERR
+                               "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
+                               (unsigned int)nodenum,
+                               (unsigned int)thisnodenum);
                         break;
                 }
         }
         kfree(node);
 
-        printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
-                nodes_got, nodes_got != 1 ? "s" : "", devs);
+        printk(KERN_INFO
+               "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
+               nodes_got, nodes_got != 1 ? "s" : "", devs);
 }
 
 /*
@@ -412,8 +416,8 @@ static void __init build_devlist(void)
  *
  */
 
-static int pnpbios_disabled; /* = 0 */
-int pnpbios_dont_use_current_config; /* = 0 */
+static int pnpbios_disabled;
+int pnpbios_dont_use_current_config;
 
 #ifndef MODULE
 static int __init pnpbios_setup(char *str)
@@ -422,9 +426,9 @@ static int __init pnpbios_setup(char *str)
 
         while ((str != NULL) && (*str != '\0')) {
                 if (strncmp(str, "off", 3) == 0)
-                        pnpbios_disabled=1;
+                        pnpbios_disabled = 1;
                 if (strncmp(str, "on", 2) == 0)
-                        pnpbios_disabled=0;
+                        pnpbios_disabled = 0;
                 invert = (strncmp(str, "no-", 3) == 0);
                 if (invert)
                         str += 3;
@@ -453,35 +457,41 @@ static int __init pnpbios_probe_system(void)
         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 
         /*
-         * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
+         * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
          * structure and, if one is found, sets up the selectors and
          * entry points
          */
-        for (check = (union pnp_bios_install_struct *) __va(0xf0000);
-             check < (union pnp_bios_install_struct *) __va(0xffff0);
+        for (check = (union pnp_bios_install_struct *)__va(0xf0000);
+             check < (union pnp_bios_install_struct *)__va(0xffff0);
              check = (void *)check + 16) {
                 if (check->fields.signature != PNP_SIGNATURE)
                         continue;
-                printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
+                printk(KERN_INFO
+                       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
+                       check);
                 length = check->fields.length;
                 if (!length) {
-                        printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
+                        printk(KERN_ERR
+                               "PnPBIOS: installation structure is invalid, skipping\n");
                         continue;
                 }
                 for (sum = 0, i = 0; i < length; i++)
                         sum += check->chars[i];
                 if (sum) {
-                        printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
+                        printk(KERN_ERR
+                               "PnPBIOS: installation structure is corrupted, skipping\n");
                         continue;
                 }
                 if (check->fields.version < 0x10) {
-                        printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
+                        printk(KERN_WARNING
+                               "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
                                check->fields.version >> 4,
                                check->fields.version & 15);
                         continue;
                 }
-                printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
-                       check->fields.version >> 4, check->fields.version & 15,
+                printk(KERN_INFO
+                       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
+                       check->fields.version >> 4, check->fields.version & 15,
                        check->fields.pm16cseg, check->fields.pm16offset,
                        check->fields.pm16dseg);
                 pnp_bios_install = check;
@@ -499,25 +509,25 @@ static int __init exploding_pnp_bios(struct dmi_system_id *d)
 }
 
 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
-        {       /* PnPBIOS GPF on boot */
-                .callback = exploding_pnp_bios,
-                .ident = "Higraded P14H",
-                .matches = {
-                        DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
-                        DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
-                        DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
-                        DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
-                },
-        },
-        {       /* PnPBIOS GPF on boot */
-                .callback = exploding_pnp_bios,
-                .ident = "ASUS P4P800",
-                .matches = {
-                        DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
-                        DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
-                },
-        },
-        { }
+        {                       /* PnPBIOS GPF on boot */
+         .callback = exploding_pnp_bios,
+         .ident = "Higraded P14H",
+         .matches = {
+                     DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
+                     DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
+                     DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
+                     DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
+                     },
+         },
+        {                       /* PnPBIOS GPF on boot */
+         .callback = exploding_pnp_bios,
+         .ident = "ASUS P4P800",
+         .matches = {
+                     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
+                     DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
+                     },
+         },
+        {}
 };
 
 static int __init pnpbios_init(void)
@@ -533,14 +543,13 @@ static int __init pnpbios_init(void)
                 printk(KERN_INFO "PnPBIOS: Disabled\n");
                 return -ENODEV;
         }
-
 #ifdef CONFIG_PNPACPI
         if (!acpi_disabled && !pnpacpi_disabled) {
                 pnpbios_disabled = 1;
                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
                 return -ENODEV;
         }
-#endif /* CONFIG_ACPI */
+#endif                          /* CONFIG_ACPI */
 
         /* scan the system for pnpbios support */
         if (!pnpbios_probe_system())
@@ -552,14 +561,16 @@ static int __init pnpbios_init(void)
         /* read the node info */
         ret = pnp_bios_dev_node_info(&node_info);
         if (ret) {
-                printk(KERN_ERR "PnPBIOS: Unable to get node info.  Aborting.\n");
+                printk(KERN_ERR
+                       "PnPBIOS: Unable to get node info.  Aborting.\n");
                 return ret;
         }
 
         /* register with the pnp layer */
         ret = pnp_register_protocol(&pnpbios_protocol);
         if (ret) {
-                printk(KERN_ERR "PnPBIOS: Unable to register driver.  Aborting.\n");
+                printk(KERN_ERR
+                       "PnPBIOS: Unable to register driver.  Aborting.\n");
                 return ret;
         }
 
diff --git a/drivers/pnp/pnpbios/proc.c b/drivers/pnp/pnpbios/proc.c
index 8027073f7919..9c8c07701b65 100644
--- a/drivers/pnp/pnpbios/proc.c
+++ b/drivers/pnp/pnpbios/proc.c
@@ -18,9 +18,6 @@
  * The other files are human-readable.
  */
 
-//#include <pcmcia/config.h>
-//#include <pcmcia/k_compat.h>
-
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
@@ -37,42 +34,37 @@ static struct proc_dir_entry *proc_pnp = NULL;
 static struct proc_dir_entry *proc_pnp_boot = NULL;
 
 static int proc_read_pnpconfig(char *buf, char **start, off_t pos,
-                               int count, int *eof, void *data)
+                               int count, int *eof, void *data)
 {
         struct pnp_isa_config_struc pnps;
 
         if (pnp_bios_isapnp_config(&pnps))
                 return -EIO;
         return snprintf(buf, count,
-                "structure_revision %d\n"
-                "number_of_CSNs %d\n"
-                "ISA_read_data_port 0x%x\n",
-                pnps.revision,
-                pnps.no_csns,
-                pnps.isa_rd_data_port
-        );
+                        "structure_revision %d\n"
+                        "number_of_CSNs %d\n"
+                        "ISA_read_data_port 0x%x\n",
+                        pnps.revision, pnps.no_csns, pnps.isa_rd_data_port);
 }
 
 static int proc_read_escdinfo(char *buf, char **start, off_t pos,
-                              int count, int *eof, void *data)
+                              int count, int *eof, void *data)
 {
         struct escd_info_struc escd;
 
         if (pnp_bios_escd_info(&escd))
                 return -EIO;
         return snprintf(buf, count,
-                "min_ESCD_write_size %d\n"
-                "ESCD_size %d\n"
-                "NVRAM_base 0x%x\n",
-                escd.min_escd_write_size,
-                escd.escd_size,
-                escd.nv_storage_base
-        );
+                        "min_ESCD_write_size %d\n"
+                        "ESCD_size %d\n"
+                        "NVRAM_base 0x%x\n",
+                        escd.min_escd_write_size,
+                        escd.escd_size, escd.nv_storage_base);
 }
 
 #define MAX_SANE_ESCD_SIZE (32*1024)
 static int proc_read_escd(char *buf, char **start, off_t pos,
-                          int count, int *eof, void *data)
+                          int count, int *eof, void *data)
 {
         struct escd_info_struc escd;
         char *tmpbuf;
@@ -83,30 +75,36 @@ static int proc_read_escd(char *buf, char **start, off_t pos,
 
         /* sanity check */
         if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
-                printk(KERN_ERR "PnPBIOS: proc_read_escd: ESCD size reported by BIOS escd_info call is too great\n");
+                printk(KERN_ERR
+                       "PnPBIOS: proc_read_escd: ESCD size reported by BIOS escd_info call is too great\n");
                 return -EFBIG;
         }
 
         tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
-        if (!tmpbuf) return -ENOMEM;
+        if (!tmpbuf)
+                return -ENOMEM;
 
         if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
                 kfree(tmpbuf);
                 return -EIO;
         }
 
-        escd_size = (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1])*256;
+        escd_size =
+            (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
 
         /* sanity check */
         if (escd_size > MAX_SANE_ESCD_SIZE) {
-                printk(KERN_ERR "PnPBIOS: proc_read_escd: ESCD size reported by BIOS read_escd call is too great\n");
+                printk(KERN_ERR
+                       "PnPBIOS: proc_read_escd: ESCD size reported by BIOS read_escd call is too great\n");
                 return -EFBIG;
         }
 
         escd_left_to_read = escd_size - pos;
-        if (escd_left_to_read < 0) escd_left_to_read = 0;
-        if (escd_left_to_read == 0) *eof = 1;
-        n = min(count,escd_left_to_read);
+        if (escd_left_to_read < 0)
+                escd_left_to_read = 0;
+        if (escd_left_to_read == 0)
+                *eof = 1;
+        n = min(count, escd_left_to_read);
         memcpy(buf, tmpbuf + pos, n);
         kfree(tmpbuf);
         *start = buf;
@@ -114,17 +112,17 @@ static int proc_read_escd(char *buf, char **start, off_t pos,
 }
 
 static int proc_read_legacyres(char *buf, char **start, off_t pos,
-                               int count, int *eof, void *data)
+                               int count, int *eof, void *data)
 {
         /* Assume that the following won't overflow the buffer */
-        if (pnp_bios_get_stat_res(buf)) 
+        if (pnp_bios_get_stat_res(buf))
                 return -EIO;
 
-        return count;  // FIXME: Return actual length
+        return count;           // FIXME: Return actual length
 }
 
 static int proc_read_devices(char *buf, char **start, off_t pos,
-                             int count, int *eof, void *data)
+                             int count, int *eof, void *data)
 {
         struct pnp_bios_node *node;
         u8 nodenum;
@@ -134,9 +132,10 @@ static int proc_read_devices(char *buf, char **start, off_t pos,
                 return 0;
 
         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
-        if (!node) return -ENOMEM;
+        if (!node)
+                return -ENOMEM;
 
-        for (nodenum=pos; nodenum<0xff; ) {
+        for (nodenum = pos; nodenum < 0xff;) {
                 u8 thisnodenum = nodenum;
                 /* 26 = the number of characters per line sprintf'ed */
                 if ((p - buf + 26) > count)
@@ -148,7 +147,11 @@ static int proc_read_devices(char *buf, char **start, off_t pos,
                              node->type_code[0], node->type_code[1],
                              node->type_code[2], node->flags);
                 if (nodenum <= thisnodenum) {
-                        printk(KERN_ERR "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n", "PnPBIOS: proc_read_devices:", (unsigned int)nodenum, (unsigned int)thisnodenum);
+                        printk(KERN_ERR
+                               "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
+                               "PnPBIOS: proc_read_devices:",
+                               (unsigned int)nodenum,
+                               (unsigned int)thisnodenum);
                         *eof = 1;
                         break;
                 }
@@ -156,12 +159,12 @@ static int proc_read_devices(char *buf, char **start, off_t pos,
         kfree(node);
         if (nodenum == 0xff)
                 *eof = 1;
-        *start = (char *)((off_t)nodenum - pos);
+        *start = (char *)((off_t) nodenum - pos);
         return p - buf;
 }
 
 static int proc_read_node(char *buf, char **start, off_t pos,
-                          int count, int *eof, void *data)
+                          int count, int *eof, void *data)
 {
         struct pnp_bios_node *node;
         int boot = (long)data >> 8;
@@ -169,7 +172,8 @@ static int proc_read_node(char *buf, char **start, off_t pos,
         int len;
 
         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
-        if (!node) return -ENOMEM;
+        if (!node)
+                return -ENOMEM;
         if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
                 kfree(node);
                 return -EIO;
@@ -180,8 +184,8 @@ static int proc_read_node(char *buf, char **start, off_t pos,
         return len;
 }
 
-static int proc_write_node(struct file *file, const char __user *buf,
-                           unsigned long count, void *data)
+static int proc_write_node(struct file *file, const char __user * buf,
+                           unsigned long count, void *data)
 {
         struct pnp_bios_node *node;
         int boot = (long)data >> 8;
@@ -208,12 +212,12 @@ static int proc_write_node(struct file *file, const char __user *buf,
                 goto out;
         }
         ret = count;
-out:
+      out:
         kfree(node);
         return ret;
 }
 
-int pnpbios_interface_attach_device(struct pnp_bios_node * node)
+int pnpbios_interface_attach_device(struct pnp_bios_node *node)
 {
         char name[3];
         struct proc_dir_entry *ent;
@@ -222,7 +226,7 @@ int pnpbios_interface_attach_device(struct pnp_bios_node * node)
 
         if (!proc_pnp)
                 return -EIO;
-        if ( !pnpbios_dont_use_current_config ) {
+        if (!pnpbios_dont_use_current_config) {
                 ent = create_proc_entry(name, 0, proc_pnp);
                 if (ent) {
                         ent->read_proc = proc_read_node;
@@ -237,7 +241,7 @@ int pnpbios_interface_attach_device(struct pnp_bios_node * node)
         if (ent) {
                 ent->read_proc = proc_read_node;
                 ent->write_proc = proc_write_node;
-                ent->data = (void *)(long)(node->handle+0x100);
+                ent->data = (void *)(long)(node->handle + 0x100);
                 return 0;
         }
 
@@ -249,7 +253,7 @@ int pnpbios_interface_attach_device(struct pnp_bios_node * node)
  * work and the pnpbios_dont_use_current_config flag
  * should already have been set to the appropriate value
  */
-int __init pnpbios_proc_init( void )
+int __init pnpbios_proc_init(void)
 {
         proc_pnp = proc_mkdir("pnp", proc_bus);
         if (!proc_pnp)
@@ -258,10 +262,13 @@ int __init pnpbios_proc_init( void )
         if (!proc_pnp_boot)
                 return -EIO;
         create_proc_read_entry("devices", 0, proc_pnp, proc_read_devices, NULL);
-        create_proc_read_entry("configuration_info", 0, proc_pnp, proc_read_pnpconfig, NULL);
-        create_proc_read_entry("escd_info", 0, proc_pnp, proc_read_escdinfo, NULL);
+        create_proc_read_entry("configuration_info", 0, proc_pnp,
+                               proc_read_pnpconfig, NULL);
+        create_proc_read_entry("escd_info", 0, proc_pnp, proc_read_escdinfo,
+                               NULL);
         create_proc_read_entry("escd", S_IRUSR, proc_pnp, proc_read_escd, NULL);
-        create_proc_read_entry("legacy_device_resources", 0, proc_pnp, proc_read_legacyres, NULL);
+        create_proc_read_entry("legacy_device_resources", 0, proc_pnp,
+                               proc_read_legacyres, NULL);
 
         return 0;
 }
@@ -274,9 +281,9 @@ void __exit pnpbios_proc_exit(void)
         if (!proc_pnp)
                 return;
 
-        for (i=0; i<0xff; i++) {
+        for (i = 0; i < 0xff; i++) {
                 sprintf(name, "%02x", i);
-                if ( !pnpbios_dont_use_current_config )
+                if (!pnpbios_dont_use_current_config)
                         remove_proc_entry(name, proc_pnp);
                 remove_proc_entry(name, proc_pnp_boot);
         }
@@ -287,6 +294,4 @@ void __exit pnpbios_proc_exit(void)
         remove_proc_entry("devices", proc_pnp);
         remove_proc_entry("boot", proc_pnp);
         remove_proc_entry("pnp", proc_bus);
-
-        return;
 }
diff --git a/drivers/pnp/pnpbios/rsparser.c b/drivers/pnp/pnpbios/rsparser.c
index 3c2ab8394e3f..04ecd7b67230 100644
--- a/drivers/pnp/pnpbios/rsparser.c
+++ b/drivers/pnp/pnpbios/rsparser.c
@@ -1,6 +1,5 @@
 /*
  * rsparser.c - parses and encodes pnpbios resource data streams
- *
  */
 
 #include <linux/ctype.h>
@@ -12,8 +11,10 @@
 #ifdef CONFIG_PCI
 #include <linux/pci.h>
 #else
-inline void pcibios_penalize_isa_irq(int irq, int active) {}
-#endif /* CONFIG_PCI */
+inline void pcibios_penalize_isa_irq(int irq, int active)
+{
+}
+#endif                          /* CONFIG_PCI */
 
 #include "pnpbios.h"
 
@@ -52,75 +53,88 @@ inline void pcibios_penalize_isa_irq(int irq, int active) {}
  * Allocated Resources
  */
 
-static void
-pnpbios_parse_allocated_irqresource(struct pnp_resource_table * res, int irq)
+static void pnpbios_parse_allocated_irqresource(struct pnp_resource_table *res,
+                                                int irq)
 {
         int i = 0;
-        while (!(res->irq_resource[i].flags & IORESOURCE_UNSET) && i < PNP_MAX_IRQ) i++;
+
+        while (!(res->irq_resource[i].flags & IORESOURCE_UNSET)
+               && i < PNP_MAX_IRQ)
+                i++;
         if (i < PNP_MAX_IRQ) {
-                res->irq_resource[i].flags = IORESOURCE_IRQ;  // Also clears _UNSET flag
+                res->irq_resource[i].flags = IORESOURCE_IRQ;    // Also clears _UNSET flag
                 if (irq == -1) {
                         res->irq_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
                 res->irq_resource[i].start =
-                res->irq_resource[i].end = (unsigned long) irq;
+                    res->irq_resource[i].end = (unsigned long)irq;
                 pcibios_penalize_isa_irq(irq, 1);
         }
 }
 
-static void
-pnpbios_parse_allocated_dmaresource(struct pnp_resource_table * res, int dma)
+static void pnpbios_parse_allocated_dmaresource(struct pnp_resource_table *res,
+                                                int dma)
 {
         int i = 0;
+
         while (i < PNP_MAX_DMA &&
-                        !(res->dma_resource[i].flags & IORESOURCE_UNSET))
+               !(res->dma_resource[i].flags & IORESOURCE_UNSET))
                 i++;
         if (i < PNP_MAX_DMA) {
-                res->dma_resource[i].flags = IORESOURCE_DMA;  // Also clears _UNSET flag
+                res->dma_resource[i].flags = IORESOURCE_DMA;    // Also clears _UNSET flag
                 if (dma == -1) {
                         res->dma_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
                 res->dma_resource[i].start =
-                res->dma_resource[i].end = (unsigned long) dma;
+                    res->dma_resource[i].end = (unsigned long)dma;
         }
 }
 
-static void
-pnpbios_parse_allocated_ioresource(struct pnp_resource_table * res, int io, int len)
+static void pnpbios_parse_allocated_ioresource(struct pnp_resource_table *res,
+                                               int io, int len)
 {
         int i = 0;
-        while (!(res->port_resource[i].flags & IORESOURCE_UNSET) && i < PNP_MAX_PORT) i++;
+
+        while (!(res->port_resource[i].flags & IORESOURCE_UNSET)
+               && i < PNP_MAX_PORT)
+                i++;
         if (i < PNP_MAX_PORT) {
-                res->port_resource[i].flags = IORESOURCE_IO;  // Also clears _UNSET flag
-                if (len <= 0 || (io + len -1) >= 0x10003) {
+                res->port_resource[i].flags = IORESOURCE_IO;    // Also clears _UNSET flag
+                if (len <= 0 || (io + len - 1) >= 0x10003) {
                         res->port_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
-                res->port_resource[i].start = (unsigned long) io;
+                res->port_resource[i].start = (unsigned long)io;
                 res->port_resource[i].end = (unsigned long)(io + len - 1);
         }
 }
 
-static void
-pnpbios_parse_allocated_memresource(struct pnp_resource_table * res, int mem, int len)
+static void pnpbios_parse_allocated_memresource(struct pnp_resource_table *res,
+                                                int mem, int len)
 {
         int i = 0;
-        while (!(res->mem_resource[i].flags & IORESOURCE_UNSET) && i < PNP_MAX_MEM) i++;
+
+        while (!(res->mem_resource[i].flags & IORESOURCE_UNSET)
+               && i < PNP_MAX_MEM)
+                i++;
         if (i < PNP_MAX_MEM) {
-                res->mem_resource[i].flags = IORESOURCE_MEM;  // Also clears _UNSET flag
+                res->mem_resource[i].flags = IORESOURCE_MEM;    // Also clears _UNSET flag
                 if (len <= 0) {
                         res->mem_resource[i].flags |= IORESOURCE_DISABLED;
                         return;
                 }
-                res->mem_resource[i].start = (unsigned long) mem;
+                res->mem_resource[i].start = (unsigned long)mem;
                 res->mem_resource[i].end = (unsigned long)(mem + len - 1);
         }
 }
 
-static unsigned char *
-pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, struct pnp_resource_table * res)
+static unsigned char *pnpbios_parse_allocated_resource_data(unsigned char *p,
+                                                            unsigned char *end,
+                                                            struct
+                                                            pnp_resource_table
+                                                            *res)
 {
         unsigned int len, tag;
         int io, size, mask, i;
@@ -134,12 +148,12 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
         while ((char *)p < (char *)end) {
 
                 /* determine the type of tag */
-                if (p[0] & LARGE_TAG) { /* large tag */
+                if (p[0] & LARGE_TAG) { /* large tag */
                         len = (p[2] << 8) | p[1];
                         tag = p[0];
-                } else { /* small tag */
+                } else {        /* small tag */
                         len = p[0] & 0x07;
-                        tag = ((p[0]>>3) & 0x0f);
+                        tag = ((p[0] >> 3) & 0x0f);
                 }
 
                 switch (tag) {
@@ -147,8 +161,8 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
                 case LARGE_TAG_MEM:
                         if (len != 9)
                                 goto len_err;
-                        io = *(short *) &p[4];
-                        size = *(short *) &p[10];
+                        io = *(short *)&p[4];
+                        size = *(short *)&p[10];
                         pnpbios_parse_allocated_memresource(res, io, size);
                         break;
 
@@ -163,16 +177,16 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
                 case LARGE_TAG_MEM32:
                         if (len != 17)
                                 goto len_err;
-                        io = *(int *) &p[4];
-                        size = *(int *) &p[16];
+                        io = *(int *)&p[4];
+                        size = *(int *)&p[16];
                         pnpbios_parse_allocated_memresource(res, io, size);
                         break;
 
                 case LARGE_TAG_FIXEDMEM32:
                         if (len != 9)
                                 goto len_err;
-                        io = *(int *) &p[4];
-                        size = *(int *) &p[8];
+                        io = *(int *)&p[4];
+                        size = *(int *)&p[8];
                         pnpbios_parse_allocated_memresource(res, io, size);
                         break;
 
@@ -180,9 +194,10 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
                         if (len < 2 || len > 3)
                                 goto len_err;
                         io = -1;
-                        mask= p[1] + p[2]*256;
-                        for (i=0;i<16;i++, mask=mask>>1)
-                                if(mask & 0x01) io=i;
+                        mask = p[1] + p[2] * 256;
+                        for (i = 0; i < 16; i++, mask = mask >> 1)
+                                if (mask & 0x01)
+                                        io = i;
                         pnpbios_parse_allocated_irqresource(res, io);
                         break;
 
@@ -191,15 +206,16 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
                                 goto len_err;
                         io = -1;
                         mask = p[1];
-                        for (i=0;i<8;i++, mask = mask>>1)
-                                if(mask & 0x01) io=i;
+                        for (i = 0; i < 8; i++, mask = mask >> 1)
+                                if (mask & 0x01)
+                                        io = i;
                         pnpbios_parse_allocated_dmaresource(res, io);
                         break;
 
                 case SMALL_TAG_PORT:
                         if (len != 7)
                                 goto len_err;
-                        io = p[2] + p[3] *256;
+                        io = p[2] + p[3] * 256;
                         size = p[7];
                         pnpbios_parse_allocated_ioresource(res, io, size);
                         break;
@@ -218,12 +234,14 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
 
                 case SMALL_TAG_END:
                         p = p + 2;
-                        return (unsigned char *)p;
+                        return (unsigned char *)p;
                         break;
 
-                default: /* an unkown tag */
-                        len_err:
-                        printk(KERN_ERR "PnPBIOS: Unknown tag '0x%x', length '%d'.\n", tag, len);
+                default:        /* an unkown tag */
+                      len_err:
+                        printk(KERN_ERR
+                               "PnPBIOS: Unknown tag '0x%x', length '%d'.\n",
+                               tag, len);
                         break;
                 }
 
@@ -234,20 +252,21 @@ pnpbios_parse_allocated_resource_data(unsigned char * p, unsigned char * end, st
                         p += len + 1;
         }
 
-        printk(KERN_ERR "PnPBIOS: Resource structure does not contain an end tag.\n");
+        printk(KERN_ERR
+               "PnPBIOS: Resource structure does not contain an end tag.\n");
 
         return NULL;
 }
 
-
 /*
  * Resource Configuration Options
  */
 
-static void
-pnpbios_parse_mem_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_mem_option(unsigned char *p, int size,
+                                     struct pnp_option *option)
 {
-        struct pnp_mem * mem;
+        struct pnp_mem *mem;
+
         mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
         if (!mem)
                 return;
@@ -256,14 +275,14 @@ pnpbios_parse_mem_option(unsigned char *p, int size, struct pnp_option *option)
         mem->align = (p[9] << 8) | p[8];
         mem->size = ((p[11] << 8) | p[10]) << 8;
         mem->flags = p[3];
-        pnp_register_mem_resource(option,mem);
-        return;
+        pnp_register_mem_resource(option, mem);
 }
 
-static void
-pnpbios_parse_mem32_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_mem32_option(unsigned char *p, int size,
+                                       struct pnp_option *option)
 {
-        struct pnp_mem * mem;
+        struct pnp_mem *mem;
+
         mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
         if (!mem)
                 return;
@@ -272,14 +291,13 @@ pnpbios_parse_mem32_option(unsigned char *p, int size, struct pnp_option *option
         mem->align = (p[15] << 24) | (p[14] << 16) | (p[13] << 8) | p[12];
         mem->size = (p[19] << 24) | (p[18] << 16) | (p[17] << 8) | p[16];
         mem->flags = p[3];
-        pnp_register_mem_resource(option,mem);
-        return;
+        pnp_register_mem_resource(option, mem);
 }
 
-static void
-pnpbios_parse_fixed_mem32_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_fixed_mem32_option(unsigned char *p, int size,
+                                             struct pnp_option *option)
 {
-        struct pnp_mem * mem;
+        struct pnp_mem *mem;
         mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
         if (!mem)
                 return;
@@ -287,14 +305,13 @@ pnpbios_parse_fixed_mem32_option(unsigned char *p, int size, struct pnp_option *
         mem->size = (p[11] << 24) | (p[10] << 16) | (p[9] << 8) | p[8];
         mem->align = 0;
         mem->flags = p[3];
-        pnp_register_mem_resource(option,mem);
-        return;
+        pnp_register_mem_resource(option, mem);
 }
 
-static void
-pnpbios_parse_irq_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_irq_option(unsigned char *p, int size,
+                                     struct pnp_option *option)
 {
-        struct pnp_irq * irq;
+        struct pnp_irq *irq;
         unsigned long bits;
 
         irq = kzalloc(sizeof(struct pnp_irq), GFP_KERNEL);
@@ -306,27 +323,27 @@ pnpbios_parse_irq_option(unsigned char *p, int size, struct pnp_option *option)
                 irq->flags = p[3];
         else
                 irq->flags = IORESOURCE_IRQ_HIGHEDGE;
-        pnp_register_irq_resource(option,irq);
-        return;
+        pnp_register_irq_resource(option, irq);
 }
 
-static void
-pnpbios_parse_dma_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_dma_option(unsigned char *p, int size,
+                                     struct pnp_option *option)
 {
-        struct pnp_dma * dma;
+        struct pnp_dma *dma;
+
         dma = kzalloc(sizeof(struct pnp_dma), GFP_KERNEL);
         if (!dma)
                 return;
         dma->map = p[1];
         dma->flags = p[2];
-        pnp_register_dma_resource(option,dma);
-        return;
+        pnp_register_dma_resource(option, dma);
 }
 
-static void
-pnpbios_parse_port_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_port_option(unsigned char *p, int size,
+                                      struct pnp_option *option)
 {
-        struct pnp_port * port;
+        struct pnp_port *port;
+
         port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
         if (!port)
                 return;
@@ -335,14 +352,14 @@ pnpbios_parse_port_option(unsigned char *p, int size, struct pnp_option *option)
         port->align = p[6];
         port->size = p[7];
         port->flags = p[1] ? PNP_PORT_FLAG_16BITADDR : 0;
-        pnp_register_port_resource(option,port);
-        return;
+        pnp_register_port_resource(option, port);
 }
 
-static void
-pnpbios_parse_fixed_port_option(unsigned char *p, int size, struct pnp_option *option)
+static void pnpbios_parse_fixed_port_option(unsigned char *p, int size,
+                                            struct pnp_option *option)
 {
-        struct pnp_port * port;
+        struct pnp_port *port;
+
         port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
         if (!port)
                 return;
@@ -350,12 +367,12 @@ pnpbios_parse_fixed_port_option(unsigned char *p, int size, struct pnp_option *o
         port->size = p[3];
         port->align = 0;
         port->flags = PNP_PORT_FLAG_FIXED;
-        pnp_register_port_resource(option,port);
-        return;
+        pnp_register_port_resource(option, port);
 }
 
-static unsigned char *
-pnpbios_parse_resource_option_data(unsigned char * p, unsigned char * end, struct pnp_dev *dev)
+static unsigned char *pnpbios_parse_resource_option_data(unsigned char *p,
+                                                         unsigned char *end,
+                                                         struct pnp_dev *dev)
 {
         unsigned int len, tag;
         int priority = 0;
@@ -371,12 +388,12 @@ pnpbios_parse_resource_option_data(unsigned char * p, unsigned char * end, struc
         while ((char *)p < (char *)end) {
 
                 /* determine the type of tag */
-                if (p[0] & LARGE_TAG) { /* large tag */
+                if (p[0] & LARGE_TAG) { /* large tag */
                         len = (p[2] << 8) | p[1];
                         tag = p[0];
-                } else { /* small tag */
+                } else {        /* small tag */
                         len = p[0] & 0x07;
-                        tag = ((p[0]>>3) & 0x0f);
+                        tag = ((p[0] >> 3) & 0x0f);
                 }
 
                 switch (tag) {
@@ -442,16 +459,19 @@ pnpbios_parse_resource_option_data(unsigned char * p, unsigned char * end, struc
                         if (len != 0)
                                 goto len_err;
                         if (option_independent == option)
-                                printk(KERN_WARNING "PnPBIOS: Missing SMALL_TAG_STARTDEP tag\n");
+                                printk(KERN_WARNING
+                                       "PnPBIOS: Missing SMALL_TAG_STARTDEP tag\n");
                         option = option_independent;
                         break;
 
                 case SMALL_TAG_END:
-                        return p + 2;
+                        return p + 2;
 
-                default: /* an unkown tag */
-                        len_err:
-                        printk(KERN_ERR "PnPBIOS: Unknown tag '0x%x', length '%d'.\n", tag, len);
+                default:        /* an unkown tag */
+                      len_err:
+                        printk(KERN_ERR
+                               "PnPBIOS: Unknown tag '0x%x', length '%d'.\n",
+                               tag, len);
                         break;
                 }
 
@@ -462,19 +482,18 @@ pnpbios_parse_resource_option_data(unsigned char * p, unsigned char * end, struc
                         p += len + 1;
         }
 
-        printk(KERN_ERR "PnPBIOS: Resource structure does not contain an end tag.\n");
+        printk(KERN_ERR
+               "PnPBIOS: Resource structure does not contain an end tag.\n");
 
         return NULL;
 }
 
-
 /*
  * Compatible Device IDs
  */
 
 #define HEX(id,a) hex[((id)>>a) & 15]
 #define CHAR(id,a) (0x40 + (((id)>>a) & 31))
-//
 
 void pnpid32_to_pnpid(u32 id, char *str)
 {
@@ -483,21 +502,20 @@ void pnpid32_to_pnpid(u32 id, char *str)
         id = be32_to_cpu(id);
         str[0] = CHAR(id, 26);
         str[1] = CHAR(id, 21);
-        str[2] = CHAR(id,16);
+        str[2] = CHAR(id, 16);
         str[3] = HEX(id, 12);
         str[4] = HEX(id, 8);
         str[5] = HEX(id, 4);
         str[6] = HEX(id, 0);
         str[7] = '\0';
-
-        return;
 }
-//
+
 #undef CHAR
 #undef HEX
 
-static unsigned char *
-pnpbios_parse_compatible_ids(unsigned char *p, unsigned char *end, struct pnp_dev *dev)
+static unsigned char *pnpbios_parse_compatible_ids(unsigned char *p,
+                                                   unsigned char *end,
+                                                   struct pnp_dev *dev)
 {
         int len, tag;
         char id[8];
@@ -509,40 +527,45 @@ pnpbios_parse_compatible_ids(unsigned char *p, unsigned char *end, struct pnp_de
         while ((char *)p < (char *)end) {
 
                 /* determine the type of tag */
-                if (p[0] & LARGE_TAG) { /* large tag */
+                if (p[0] & LARGE_TAG) { /* large tag */
                         len = (p[2] << 8) | p[1];
                         tag = p[0];
-                } else { /* small tag */
+                } else {        /* small tag */
                         len = p[0] & 0x07;
-                        tag = ((p[0]>>3) & 0x0f);
+                        tag = ((p[0] >> 3) & 0x0f);
                 }
 
                 switch (tag) {
 
                 case LARGE_TAG_ANSISTR:
-                        strncpy(dev->name, p + 3, len >= PNP_NAME_LEN ? PNP_NAME_LEN - 2 : len);
-                        dev->name[len >= PNP_NAME_LEN ? PNP_NAME_LEN - 1 : len] = '\0';
+                        strncpy(dev->name, p + 3,
+                                len >= PNP_NAME_LEN ? PNP_NAME_LEN - 2 : len);
+                        dev->name[len >=
+                                  PNP_NAME_LEN ? PNP_NAME_LEN - 1 : len] = '\0';
                         break;
 
-                case SMALL_TAG_COMPATDEVID: /* compatible ID */
+                case SMALL_TAG_COMPATDEVID:     /* compatible ID */
                         if (len != 4)
                                 goto len_err;
-                        dev_id =  kzalloc(sizeof (struct pnp_id), GFP_KERNEL);
+                        dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
                         if (!dev_id)
                                 return NULL;
-                        pnpid32_to_pnpid(p[1] | p[2] << 8 | p[3] << 16 | p[4] << 24,id);
+                        pnpid32_to_pnpid(p[1] | p[2] << 8 | p[3] << 16 | p[4] <<
+                                         24, id);
                         memcpy(&dev_id->id, id, 7);
                         pnp_add_id(dev_id, dev);
                         break;
 
                 case SMALL_TAG_END:
                         p = p + 2;
-                        return (unsigned char *)p;
+                        return (unsigned char *)p;
                         break;
 
-                default: /* an unkown tag */
-                        len_err:
-                        printk(KERN_ERR "PnPBIOS: Unknown tag '0x%x', length '%d'.\n", tag, len);
+                default:        /* an unkown tag */
+                      len_err:
+                        printk(KERN_ERR
+                               "PnPBIOS: Unknown tag '0x%x', length '%d'.\n",
+                               tag, len);
                         break;
                 }
 
@@ -553,33 +576,34 @@ pnpbios_parse_compatible_ids(unsigned char *p, unsigned char *end, struct pnp_de
                         p += len + 1;
         }
 
-        printk(KERN_ERR "PnPBIOS: Resource structure does not contain an end tag.\n");
+        printk(KERN_ERR
+               "PnPBIOS: Resource structure does not contain an end tag.\n");
 
         return NULL;
 }
 
-
 /*
  * Allocated Resource Encoding
  */
 
-static void pnpbios_encode_mem(unsigned char *p, struct resource * res)
+static void pnpbios_encode_mem(unsigned char *p, struct resource *res)
 {
         unsigned long base = res->start;
         unsigned long len = res->end - res->start + 1;
+
         p[4] = (base >> 8) & 0xff;
         p[5] = ((base >> 8) >> 8) & 0xff;
         p[6] = (base >> 8) & 0xff;
         p[7] = ((base >> 8) >> 8) & 0xff;
         p[10] = (len >> 8) & 0xff;
         p[11] = ((len >> 8) >> 8) & 0xff;
-        return;
 }
 
-static void pnpbios_encode_mem32(unsigned char *p, struct resource * res)
+static void pnpbios_encode_mem32(unsigned char *p, struct resource *res)
 {
         unsigned long base = res->start;
         unsigned long len = res->end - res->start + 1;
+
         p[4] = base & 0xff;
         p[5] = (base >> 8) & 0xff;
         p[6] = (base >> 16) & 0xff;
@@ -592,12 +616,13 @@ static void pnpbios_encode_mem32(unsigned char *p, struct resource * res)
         p[17] = (len >> 8) & 0xff;
         p[18] = (len >> 16) & 0xff;
         p[19] = (len >> 24) & 0xff;
-        return;
 }
 
-static void pnpbios_encode_fixed_mem32(unsigned char *p, struct resource * res)
-{       unsigned long base = res->start;
+static void pnpbios_encode_fixed_mem32(unsigned char *p, struct resource *res)
+{
+        unsigned long base = res->start;
         unsigned long len = res->end - res->start + 1;
+
         p[4] = base & 0xff;
         p[5] = (base >> 8) & 0xff;
         p[6] = (base >> 16) & 0xff;
@@ -606,50 +631,52 @@ static void pnpbios_encode_fixed_mem32(unsigned char *p, struct resource * res)
         p[9] = (len >> 8) & 0xff;
         p[10] = (len >> 16) & 0xff;
         p[11] = (len >> 24) & 0xff;
-        return;
 }
 
-static void pnpbios_encode_irq(unsigned char *p, struct resource * res)
+static void pnpbios_encode_irq(unsigned char *p, struct resource *res)
 {
         unsigned long map = 0;
+
         map = 1 << res->start;
         p[1] = map & 0xff;
         p[2] = (map >> 8) & 0xff;
-        return;
 }
 
-static void pnpbios_encode_dma(unsigned char *p, struct resource * res)
+static void pnpbios_encode_dma(unsigned char *p, struct resource *res)
 {
         unsigned long map = 0;
+
         map = 1 << res->start;
         p[1] = map & 0xff;
-        return;
 }
 
-static void pnpbios_encode_port(unsigned char *p, struct resource * res)
+static void pnpbios_encode_port(unsigned char *p, struct resource *res)
 {
         unsigned long base = res->start;
         unsigned long len = res->end - res->start + 1;
+
         p[2] = base & 0xff;
         p[3] = (base >> 8) & 0xff;
         p[4] = base & 0xff;
         p[5] = (base >> 8) & 0xff;
         p[7] = len & 0xff;
-        return;
 }
 
-static void pnpbios_encode_fixed_port(unsigned char *p, struct resource * res)
+static void pnpbios_encode_fixed_port(unsigned char *p, struct resource *res)
 {
         unsigned long base = res->start;
         unsigned long len = res->end - res->start + 1;
+
         p[1] = base & 0xff;
         p[2] = (base >> 8) & 0xff;
         p[3] = len & 0xff;
-        return;
 }
 
-static unsigned char *
-pnpbios_encode_allocated_resource_data(unsigned char * p, unsigned char * end, struct pnp_resource_table * res)
+static unsigned char *pnpbios_encode_allocated_resource_data(unsigned char *p,
+                                                             unsigned char *end,
+                                                             struct
+                                                             pnp_resource_table
+                                                             *res)
 {
         unsigned int len, tag;
         int port = 0, irq = 0, dma = 0, mem = 0;
@@ -660,12 +687,12 @@ pnpbios_encode_allocated_resource_data(unsigned char * p, unsigned char * end, s
         while ((char *)p < (char *)end) {
 
                 /* determine the type of tag */
-                if (p[0] & LARGE_TAG) { /* large tag */
+                if (p[0] & LARGE_TAG) { /* large tag */
                         len = (p[2] << 8) | p[1];
                         tag = p[0];
-                } else { /* small tag */
+                } else {        /* small tag */
                         len = p[0] & 0x07;
-                        tag = ((p[0]>>3) & 0x0f);
+                        tag = ((p[0] >> 3) & 0x0f);
                 }
 
                 switch (tag) {
@@ -725,12 +752,14 @@ pnpbios_encode_allocated_resource_data(unsigned char * p, unsigned char * end, s
 
                 case SMALL_TAG_END:
                         p = p + 2;
-                        return (unsigned char *)p;
+                        return (unsigned char *)p;
                         break;
 
-                default: /* an unkown tag */
-                        len_err:
-                        printk(KERN_ERR "PnPBIOS: Unknown tag '0x%x', length '%d'.\n", tag, len);
+                default:        /* an unkown tag */
+                      len_err:
+                        printk(KERN_ERR
+                               "PnPBIOS: Unknown tag '0x%x', length '%d'.\n",
+                               tag, len);
                         break;
                 }
 
@@ -741,52 +770,52 @@ pnpbios_encode_allocated_resource_data(unsigned char * p, unsigned char * end, s
                         p += len + 1;
         }
 
-        printk(KERN_ERR "PnPBIOS: Resource structure does not contain an end tag.\n");
+        printk(KERN_ERR
+               "PnPBIOS: Resource structure does not contain an end tag.\n");
 
         return NULL;
 }
 
-
 /*
  * Core Parsing Functions
  */
 
-int
-pnpbios_parse_data_stream(struct pnp_dev *dev, struct pnp_bios_node * node)
+int pnpbios_parse_data_stream(struct pnp_dev *dev, struct pnp_bios_node *node)
 {
-        unsigned char * p = (char *)node->data;
-        unsigned char * end = (char *)(node->data + node->size);
-        p = pnpbios_parse_allocated_resource_data(p,end,&dev->res);
+        unsigned char *p = (char *)node->data;
+        unsigned char *end = (char *)(node->data + node->size);
+
+        p = pnpbios_parse_allocated_resource_data(p, end, &dev->res);
         if (!p)
                 return -EIO;
-        p = pnpbios_parse_resource_option_data(p,end,dev);
+        p = pnpbios_parse_resource_option_data(p, end, dev);
         if (!p)
                 return -EIO;
-        p = pnpbios_parse_compatible_ids(p,end,dev);
+        p = pnpbios_parse_compatible_ids(p, end, dev);
         if (!p)
                 return -EIO;
         return 0;
 }
 
-int
-pnpbios_read_resources_from_node(struct pnp_resource_table *res,
-                                 struct pnp_bios_node * node)
+int pnpbios_read_resources_from_node(struct pnp_resource_table *res,
+                                     struct pnp_bios_node *node)
 {
-        unsigned char * p = (char *)node->data;
-        unsigned char * end = (char *)(node->data + node->size);
-        p = pnpbios_parse_allocated_resource_data(p,end,res);
+        unsigned char *p = (char *)node->data;
+        unsigned char *end = (char *)(node->data + node->size);
+
+        p = pnpbios_parse_allocated_resource_data(p, end, res);
         if (!p)
                 return -EIO;
         return 0;
 }
 
-int
-pnpbios_write_resources_to_node(struct pnp_resource_table *res,
-                                struct pnp_bios_node * node)
+int pnpbios_write_resources_to_node(struct pnp_resource_table *res,
+                                    struct pnp_bios_node *node)
 {
-        unsigned char * p = (char *)node->data;
-        unsigned char * end = (char *)(node->data + node->size);
-        p = pnpbios_encode_allocated_resource_data(p,end,res);
+        unsigned char *p = (char *)node->data;
+        unsigned char *end = (char *)(node->data + node->size);
+
+        p = pnpbios_encode_allocated_resource_data(p, end, res);
         if (!p)
                 return -EIO;
         return 0;
diff --git a/drivers/pnp/quirks.c b/drivers/pnp/quirks.c
index 7c3236690cc3..90755d4cdb9f 100644
--- a/drivers/pnp/quirks.c
+++ b/drivers/pnp/quirks.c
@@ -19,7 +19,6 @@
 #include <linux/io.h>
 #include "base.h"
 
-
 static void quirk_awe32_resources(struct pnp_dev *dev)
 {
         struct pnp_port *port, *port2, *port3;
@@ -31,7 +30,7 @@ static void quirk_awe32_resources(struct pnp_dev *dev)
          * two extra ports (at offset 0x400 and 0x800 from the one given) by
          * hand.
          */
-        for ( ; res ; res = res->next ) {
+        for (; res; res = res->next) {
                 port2 = pnp_alloc(sizeof(struct pnp_port));
                 if (!port2)
                         return;
@@ -58,18 +57,19 @@ static void quirk_cmi8330_resources(struct pnp_dev *dev)
         struct pnp_option *res = dev->dependent;
         unsigned long tmp;
 
-        for ( ; res ; res = res->next ) {
+        for (; res; res = res->next) {
 
                 struct pnp_irq *irq;
                 struct pnp_dma *dma;
 
-                for( irq = res->irq; irq; irq = irq->next ) {   // Valid irqs are 5, 7, 10
+                for (irq = res->irq; irq; irq = irq->next) {    // Valid irqs are 5, 7, 10
                         tmp = 0x04A0;
                         bitmap_copy(irq->map, &tmp, 16);        // 0000 0100 1010 0000
                 }
 
-                for( dma = res->dma; dma; dma = dma->next ) // Valid 8bit dma channels are 1,3
-                        if( ( dma->flags & IORESOURCE_DMA_TYPE_MASK ) == IORESOURCE_DMA_8BIT )
+                for (dma = res->dma; dma; dma = dma->next)      // Valid 8bit dma channels are 1,3
+                        if ((dma->flags & IORESOURCE_DMA_TYPE_MASK) ==
+                            IORESOURCE_DMA_8BIT)
                                 dma->map = 0x000A;
         }
         printk(KERN_INFO "pnp: CMI8330 quirk - fixing interrupts and dma\n");
@@ -79,7 +79,7 @@ static void quirk_sb16audio_resources(struct pnp_dev *dev)
 {
         struct pnp_port *port;
         struct pnp_option *res = dev->dependent;
-        int    changed = 0;
+        int changed = 0;
 
         /*
          * The default range on the mpu port for these devices is 0x388-0x388.
@@ -87,24 +87,24 @@ static void quirk_sb16audio_resources(struct pnp_dev *dev)
          * auto-configured.
          */
 
-        for( ; res ; res = res->next ) {
+        for (; res; res = res->next) {
                 port = res->port;
-                if(!port)
+                if (!port)
                         continue;
                 port = port->next;
-                if(!port)
+                if (!port)
                         continue;
                 port = port->next;
-                if(!port)
+                if (!port)
                         continue;
-                if(port->min != port->max)
+                if (port->min != port->max)
                         continue;
                 port->max += 0x70;
                 changed = 1;
         }
-        if(changed)
-                printk(KERN_INFO "pnp: SB audio device quirk - increasing port range\n");
-        return;
+        if (changed)
+                printk(KERN_INFO
+                       "pnp: SB audio device quirk - increasing port range\n");
 }
 
 static int quirk_smc_fir_enabled(struct pnp_dev *dev)
@@ -124,7 +124,7 @@ static int quirk_smc_fir_enabled(struct pnp_dev *dev)
         outb(bank, firbase + 7);
 
         high = inb(firbase + 0);
-        low  = inb(firbase + 1);
+        low = inb(firbase + 1);
         chip = inb(firbase + 2);
 
         /* This corresponds to the check in smsc_ircc_present() */
@@ -153,8 +153,8 @@ static void quirk_smc_enable(struct pnp_dev *dev)
          */
         dev_err(&dev->dev, "%s not responding at SIR 0x%lx, FIR 0x%lx; "
                 "auto-configuring\n", dev->id->id,
-                (unsigned long) pnp_port_start(dev, 0),
-                (unsigned long) pnp_port_start(dev, 1));
+                (unsigned long)pnp_port_start(dev, 0),
+                (unsigned long)pnp_port_start(dev, 1));
 
         pnp_disable_dev(dev);
         pnp_init_resource_table(&dev->res);
@@ -162,8 +162,8 @@ static void quirk_smc_enable(struct pnp_dev *dev)
         pnp_activate_dev(dev);
         if (quirk_smc_fir_enabled(dev)) {
                 dev_err(&dev->dev, "responds at SIR 0x%lx, FIR 0x%lx\n",
-                        (unsigned long) pnp_port_start(dev, 0),
-                        (unsigned long) pnp_port_start(dev, 1));
+                        (unsigned long)pnp_port_start(dev, 0),
+                        (unsigned long)pnp_port_start(dev, 1));
                 return;
         }
 
@@ -175,8 +175,8 @@ static void quirk_smc_enable(struct pnp_dev *dev)
          */
         dev_err(&dev->dev, "not responding at SIR 0x%lx, FIR 0x%lx; "
                 "swapping SIR/FIR and reconfiguring\n",
-                (unsigned long) pnp_port_start(dev, 0),
-                (unsigned long) pnp_port_start(dev, 1));
+                (unsigned long)pnp_port_start(dev, 0),
+                (unsigned long)pnp_port_start(dev, 1));
 
         /*
          * Clear IORESOURCE_AUTO so pnp_activate_dev() doesn't reassign
@@ -200,8 +200,8 @@ static void quirk_smc_enable(struct pnp_dev *dev)
 
         if (quirk_smc_fir_enabled(dev)) {
                 dev_err(&dev->dev, "responds at SIR 0x%lx, FIR 0x%lx\n",
-                        (unsigned long) pnp_port_start(dev, 0),
-                        (unsigned long) pnp_port_start(dev, 1));
+                        (unsigned long)pnp_port_start(dev, 0),
+                        (unsigned long)pnp_port_start(dev, 1));
                 return;
         }
 
@@ -209,7 +209,6 @@ static void quirk_smc_enable(struct pnp_dev *dev)
                 "email bjorn.helgaas@hp.com\n");
 }
 
-
 /*
  *  PnP Quirks
  *  Cards or devices that need some tweaking due to incomplete resource info
@@ -217,21 +216,21 @@ static void quirk_smc_enable(struct pnp_dev *dev)
 
 static struct pnp_fixup pnp_fixups[] = {
         /* Soundblaster awe io port quirk */
-        { "CTL0021", quirk_awe32_resources },
-        { "CTL0022", quirk_awe32_resources },
-        { "CTL0023", quirk_awe32_resources },
+        {"CTL0021", quirk_awe32_resources},
+        {"CTL0022", quirk_awe32_resources},
+        {"CTL0023", quirk_awe32_resources},
         /* CMI 8330 interrupt and dma fix */
-        { "@X@0001", quirk_cmi8330_resources },
+        {"@X@0001", quirk_cmi8330_resources},
         /* Soundblaster audio device io port range quirk */
-        { "CTL0001", quirk_sb16audio_resources },
-        { "CTL0031", quirk_sb16audio_resources },
-        { "CTL0041", quirk_sb16audio_resources },
-        { "CTL0042", quirk_sb16audio_resources },
-        { "CTL0043", quirk_sb16audio_resources },
-        { "CTL0044", quirk_sb16audio_resources },
-        { "CTL0045", quirk_sb16audio_resources },
-        { "SMCf010", quirk_smc_enable },
-        { "" }
+        {"CTL0001", quirk_sb16audio_resources},
+        {"CTL0031", quirk_sb16audio_resources},
+        {"CTL0041", quirk_sb16audio_resources},
+        {"CTL0042", quirk_sb16audio_resources},
+        {"CTL0043", quirk_sb16audio_resources},
+        {"CTL0044", quirk_sb16audio_resources},
+        {"CTL0045", quirk_sb16audio_resources},
+        {"SMCf010", quirk_smc_enable},
+        {""}
 };
 
 void pnp_fixup_device(struct pnp_dev *dev)
@@ -239,9 +238,8 @@ void pnp_fixup_device(struct pnp_dev *dev)
         int i = 0;
 
         while (*pnp_fixups[i].id) {
-                if (compare_pnp_id(dev->id,pnp_fixups[i].id)) {
-                        pnp_dbg("Calling quirk for %s",
-                                  dev->dev.bus_id);
+                if (compare_pnp_id(dev->id, pnp_fixups[i].id)) {
+                        pnp_dbg("Calling quirk for %s", dev->dev.bus_id);
                         pnp_fixups[i].quirk_function(dev);
                 }
                 i++;
diff --git a/drivers/pnp/resource.c b/drivers/pnp/resource.c
index a685fbec4604..ea6ec14a0559 100644
--- a/drivers/pnp/resource.c
+++ b/drivers/pnp/resource.c
@@ -3,7 +3,6 @@
  *
  * based on isapnp.c resource management (c) Jaroslav Kysela <perex@suse.cz>
  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/module.h>
@@ -20,21 +19,19 @@
 #include <linux/pnp.h>
 #include "base.h"
 
-static int pnp_reserve_irq[16] = { [0 ... 15] = -1 };   /* reserve (don't use) some IRQ */
-static int pnp_reserve_dma[8] = { [0 ... 7] = -1 };     /* reserve (don't use) some DMA */
-static int pnp_reserve_io[16] = { [0 ... 15] = -1 };    /* reserve (don't use) some I/O region */
-static int pnp_reserve_mem[16] = { [0 ... 15] = -1 };   /* reserve (don't use) some memory region */
-
+static int pnp_reserve_irq[16] = {[0 ... 15] = -1 };    /* reserve (don't use) some IRQ */
+static int pnp_reserve_dma[8] = {[0 ... 7] = -1 };      /* reserve (don't use) some DMA */
+static int pnp_reserve_io[16] = {[0 ... 15] = -1 };     /* reserve (don't use) some I/O region */
+static int pnp_reserve_mem[16] = {[0 ... 15] = -1 };    /* reserve (don't use) some memory region */
 
 /*
  * option registration
  */
 
-static struct pnp_option * pnp_build_option(int priority)
+static struct pnp_option *pnp_build_option(int priority)
 {
         struct pnp_option *option = pnp_alloc(sizeof(struct pnp_option));
 
-        /* check if pnp_alloc ran out of memory */
         if (!option)
                 return NULL;
 
@@ -46,9 +43,10 @@ static struct pnp_option * pnp_build_option(int priority)
         return option;
 }
 
-struct pnp_option * pnp_register_independent_option(struct pnp_dev *dev)
+struct pnp_option *pnp_register_independent_option(struct pnp_dev *dev)
 {
         struct pnp_option *option;
+
         if (!dev)
                 return NULL;
 
@@ -61,9 +59,11 @@ struct pnp_option * pnp_register_independent_option(struct pnp_dev *dev)
         return option;
 }
 
-struct pnp_option * pnp_register_dependent_option(struct pnp_dev *dev, int priority)
+struct pnp_option *pnp_register_dependent_option(struct pnp_dev *dev,
+                                                 int priority)
 {
         struct pnp_option *option;
+
         if (!dev)
                 return NULL;
 
@@ -82,6 +82,7 @@ struct pnp_option * pnp_register_dependent_option(struct pnp_dev *dev, int prior
 int pnp_register_irq_resource(struct pnp_option *option, struct pnp_irq *data)
 {
         struct pnp_irq *ptr;
+
         if (!option)
                 return -EINVAL;
         if (!data)
@@ -110,6 +111,7 @@ int pnp_register_irq_resource(struct pnp_option *option, struct pnp_irq *data)
 int pnp_register_dma_resource(struct pnp_option *option, struct pnp_dma *data)
 {
         struct pnp_dma *ptr;
+
         if (!option)
                 return -EINVAL;
         if (!data)
@@ -129,6 +131,7 @@ int pnp_register_dma_resource(struct pnp_option *option, struct pnp_dma *data)
 int pnp_register_port_resource(struct pnp_option *option, struct pnp_port *data)
 {
         struct pnp_port *ptr;
+
         if (!option)
                 return -EINVAL;
         if (!data)
@@ -148,6 +151,7 @@ int pnp_register_port_resource(struct pnp_option *option, struct pnp_port *data)
 int pnp_register_mem_resource(struct pnp_option *option, struct pnp_mem *data)
 {
         struct pnp_mem *ptr;
+
         if (!option)
                 return -EINVAL;
         if (!data)
@@ -222,7 +226,6 @@ void pnp_free_option(struct pnp_option *option)
         }
 }
 
-
 /*
  * resource validity checking
  */
@@ -236,11 +239,12 @@ void pnp_free_option(struct pnp_option *option)
 #define cannot_compare(flags) \
 ((flags) & (IORESOURCE_UNSET | IORESOURCE_DISABLED))
 
-int pnp_check_port(struct pnp_dev * dev, int idx)
+int pnp_check_port(struct pnp_dev *dev, int idx)
 {
         int tmp;
         struct pnp_dev *tdev;
         resource_size_t *port, *end, *tport, *tend;
+
         port = &dev->res.port_resource[idx].start;
         end = &dev->res.port_resource[idx].end;
 
@@ -250,8 +254,8 @@ int pnp_check_port(struct pnp_dev * dev, int idx)
 
         /* check if the resource is already in use, skip if the
          * device is active because it itself may be in use */
-        if(!dev->active) {
-                if (__check_region(&ioport_resource, *port, length(port,end)))
+        if (!dev->active) {
+                if (__check_region(&ioport_resource, *port, length(port, end)))
                         return 0;
         }
 
@@ -259,7 +263,7 @@ int pnp_check_port(struct pnp_dev * dev, int idx)
         for (tmp = 0; tmp < 8; tmp++) {
                 int rport = pnp_reserve_io[tmp << 1];
                 int rend = pnp_reserve_io[(tmp << 1) + 1] + rport - 1;
-                if (ranged_conflict(port,end,&rport,&rend))
+                if (ranged_conflict(port, end, &rport, &rend))
                         return 0;
         }
 
@@ -268,7 +272,7 @@ int pnp_check_port(struct pnp_dev * dev, int idx)
                 if (dev->res.port_resource[tmp].flags & IORESOURCE_IO) {
                         tport = &dev->res.port_resource[tmp].start;
                         tend = &dev->res.port_resource[tmp].end;
-                        if (ranged_conflict(port,end,tport,tend))
+                        if (ranged_conflict(port, end, tport, tend))
                                 return 0;
                 }
         }
@@ -279,11 +283,12 @@ int pnp_check_port(struct pnp_dev * dev, int idx)
                         continue;
                 for (tmp = 0; tmp < PNP_MAX_PORT; tmp++) {
                         if (tdev->res.port_resource[tmp].flags & IORESOURCE_IO) {
-                                if (cannot_compare(tdev->res.port_resource[tmp].flags))
+                                if (cannot_compare
+                                    (tdev->res.port_resource[tmp].flags))
                                         continue;
                                 tport = &tdev->res.port_resource[tmp].start;
                                 tend = &tdev->res.port_resource[tmp].end;
-                                if (ranged_conflict(port,end,tport,tend))
+                                if (ranged_conflict(port, end, tport, tend))
                                         return 0;
                         }
                 }
@@ -292,11 +297,12 @@ int pnp_check_port(struct pnp_dev * dev, int idx)
         return 1;
 }
 
-int pnp_check_mem(struct pnp_dev * dev, int idx)
+int pnp_check_mem(struct pnp_dev *dev, int idx)
 {
         int tmp;
         struct pnp_dev *tdev;
         resource_size_t *addr, *end, *taddr, *tend;
+
         addr = &dev->res.mem_resource[idx].start;
         end = &dev->res.mem_resource[idx].end;
 
@@ -306,8 +312,8 @@ int pnp_check_mem(struct pnp_dev * dev, int idx)
 
         /* check if the resource is already in use, skip if the
          * device is active because it itself may be in use */
-        if(!dev->active) {
-                if (check_mem_region(*addr, length(addr,end)))
+        if (!dev->active) {
+                if (check_mem_region(*addr, length(addr, end)))
                         return 0;
         }
 
@@ -315,7 +321,7 @@ int pnp_check_mem(struct pnp_dev * dev, int idx)
         for (tmp = 0; tmp < 8; tmp++) {
                 int raddr = pnp_reserve_mem[tmp << 1];
                 int rend = pnp_reserve_mem[(tmp << 1) + 1] + raddr - 1;
-                if (ranged_conflict(addr,end,&raddr,&rend))
+                if (ranged_conflict(addr, end, &raddr, &rend))
                         return 0;
         }
 
@@ -324,7 +330,7 @@ int pnp_check_mem(struct pnp_dev * dev, int idx)
                 if (dev->res.mem_resource[tmp].flags & IORESOURCE_MEM) {
                         taddr = &dev->res.mem_resource[tmp].start;
                         tend = &dev->res.mem_resource[tmp].end;
-                        if (ranged_conflict(addr,end,taddr,tend))
+                        if (ranged_conflict(addr, end, taddr, tend))
                                 return 0;
                 }
         }
@@ -335,11 +341,12 @@ int pnp_check_mem(struct pnp_dev * dev, int idx)
                         continue;
                 for (tmp = 0; tmp < PNP_MAX_MEM; tmp++) {
                         if (tdev->res.mem_resource[tmp].flags & IORESOURCE_MEM) {
-                                if (cannot_compare(tdev->res.mem_resource[tmp].flags))
+                                if (cannot_compare
+                                    (tdev->res.mem_resource[tmp].flags))
                                         continue;
                                 taddr = &tdev->res.mem_resource[tmp].start;
                                 tend = &tdev->res.mem_resource[tmp].end;
-                                if (ranged_conflict(addr,end,taddr,tend))
+                                if (ranged_conflict(addr, end, taddr, tend))
                                         return 0;
                         }
                 }
@@ -353,11 +360,11 @@ static irqreturn_t pnp_test_handler(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
-int pnp_check_irq(struct pnp_dev * dev, int idx)
+int pnp_check_irq(struct pnp_dev *dev, int idx)
 {
         int tmp;
         struct pnp_dev *tdev;
-        resource_size_t * irq = &dev->res.irq_resource[idx].start;
+        resource_size_t *irq = &dev->res.irq_resource[idx].start;
 
         /* if the resource doesn't exist, don't complain about it */
         if (cannot_compare(dev->res.irq_resource[idx].flags))
@@ -394,9 +401,9 @@ int pnp_check_irq(struct pnp_dev * dev, int idx)
 
         /* check if the resource is already in use, skip if the
          * device is active because it itself may be in use */
-        if(!dev->active) {
+        if (!dev->active) {
                 if (request_irq(*irq, pnp_test_handler,
-                                IRQF_DISABLED|IRQF_PROBE_SHARED, "pnp", NULL))
+                                IRQF_DISABLED | IRQF_PROBE_SHARED, "pnp", NULL))
                         return 0;
                 free_irq(*irq, NULL);
         }
@@ -407,7 +414,8 @@ int pnp_check_irq(struct pnp_dev * dev, int idx)
                         continue;
                 for (tmp = 0; tmp < PNP_MAX_IRQ; tmp++) {
                         if (tdev->res.irq_resource[tmp].flags & IORESOURCE_IRQ) {
-                                if (cannot_compare(tdev->res.irq_resource[tmp].flags))
+                                if (cannot_compare
+                                    (tdev->res.irq_resource[tmp].flags))
                                         continue;
                                 if ((tdev->res.irq_resource[tmp].start == *irq))
                                         return 0;
@@ -418,12 +426,12 @@ int pnp_check_irq(struct pnp_dev * dev, int idx)
         return 1;
 }
 
-int pnp_check_dma(struct pnp_dev * dev, int idx)
+int pnp_check_dma(struct pnp_dev *dev, int idx)
 {
 #ifndef CONFIG_IA64
         int tmp;
         struct pnp_dev *tdev;
-        resource_size_t * dma = &dev->res.dma_resource[idx].start;
+        resource_size_t *dma = &dev->res.dma_resource[idx].start;
 
         /* if the resource doesn't exist, don't complain about it */
         if (cannot_compare(dev->res.dma_resource[idx].flags))
@@ -449,7 +457,7 @@ int pnp_check_dma(struct pnp_dev * dev, int idx)
 
         /* check if the resource is already in use, skip if the
          * device is active because it itself may be in use */
-        if(!dev->active) {
+        if (!dev->active) {
                 if (request_dma(*dma, "pnp"))
                         return 0;
                 free_dma(*dma);
@@ -461,7 +469,8 @@ int pnp_check_dma(struct pnp_dev * dev, int idx)
                         continue;
                 for (tmp = 0; tmp < PNP_MAX_DMA; tmp++) {
                         if (tdev->res.dma_resource[tmp].flags & IORESOURCE_DMA) {
-                                if (cannot_compare(tdev->res.dma_resource[tmp].flags))
+                                if (cannot_compare
+                                    (tdev->res.dma_resource[tmp].flags))
                                         continue;
                                 if ((tdev->res.dma_resource[tmp].start == *dma))
                                         return 0;
@@ -471,30 +480,18 @@ int pnp_check_dma(struct pnp_dev * dev, int idx)
 
         return 1;
 #else
-        /* IA64 hasn't legacy DMA */
+        /* IA64 does not have legacy DMA */
         return 0;
 #endif
 }
 
-
-#if 0
-EXPORT_SYMBOL(pnp_register_dependent_option);
-EXPORT_SYMBOL(pnp_register_independent_option);
-EXPORT_SYMBOL(pnp_register_irq_resource);
-EXPORT_SYMBOL(pnp_register_dma_resource);
-EXPORT_SYMBOL(pnp_register_port_resource);
-EXPORT_SYMBOL(pnp_register_mem_resource);
-#endif  /*  0  */
-
-
 /* format is: pnp_reserve_irq=irq1[,irq2] .... */
-
 static int __init pnp_setup_reserve_irq(char *str)
 {
         int i;
 
         for (i = 0; i < 16; i++)
-                if (get_option(&str,&pnp_reserve_irq[i]) != 2)
+                if (get_option(&str, &pnp_reserve_irq[i]) != 2)
                         break;
         return 1;
 }
@@ -502,13 +499,12 @@ static int __init pnp_setup_reserve_irq(char *str)
 __setup("pnp_reserve_irq=", pnp_setup_reserve_irq);
 
 /* format is: pnp_reserve_dma=dma1[,dma2] .... */
-
 static int __init pnp_setup_reserve_dma(char *str)
 {
         int i;
 
         for (i = 0; i < 8; i++)
-                if (get_option(&str,&pnp_reserve_dma[i]) != 2)
+                if (get_option(&str, &pnp_reserve_dma[i]) != 2)
                         break;
         return 1;
 }
@@ -516,13 +512,12 @@ static int __init pnp_setup_reserve_dma(char *str)
 __setup("pnp_reserve_dma=", pnp_setup_reserve_dma);
 
 /* format is: pnp_reserve_io=io1,size1[,io2,size2] .... */
-
 static int __init pnp_setup_reserve_io(char *str)
 {
         int i;
 
         for (i = 0; i < 16; i++)
-                if (get_option(&str,&pnp_reserve_io[i]) != 2)
+                if (get_option(&str, &pnp_reserve_io[i]) != 2)
                         break;
         return 1;
 }
@@ -530,13 +525,12 @@ static int __init pnp_setup_reserve_io(char *str)
 __setup("pnp_reserve_io=", pnp_setup_reserve_io);
 
 /* format is: pnp_reserve_mem=mem1,size1[,mem2,size2] .... */
-
 static int __init pnp_setup_reserve_mem(char *str)
 {
         int i;
 
         for (i = 0; i < 16; i++)
-                if (get_option(&str,&pnp_reserve_mem[i]) != 2)
+                if (get_option(&str, &pnp_reserve_mem[i]) != 2)
                         break;
         return 1;
 }
diff --git a/drivers/pnp/support.c b/drivers/pnp/support.c
index 946a0dcd627d..13c608f5fb30 100644
--- a/drivers/pnp/support.c
+++ b/drivers/pnp/support.c
@@ -1,8 +1,7 @@
 /*
- * support.c - provides standard pnp functions for the use of pnp protocol drivers,
+ * support.c - standard functions for the use of pnp protocol drivers
  *
  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #include <linux/module.h>
@@ -11,22 +10,18 @@
 #include "base.h"
 
 /**
- * pnp_is_active - Determines if a device is active based on its current resources
+ * pnp_is_active - Determines if a device is active based on its current
+ *      resources
  * @dev: pointer to the desired PnP device
- *
  */
-
-int pnp_is_active(struct pnp_dev * dev)
+int pnp_is_active(struct pnp_dev *dev)
 {
         if (!pnp_port_start(dev, 0) && pnp_port_len(dev, 0) <= 1 &&
             !pnp_mem_start(dev, 0) && pnp_mem_len(dev, 0) <= 1 &&
-            pnp_irq(dev, 0) == -1 &&
-            pnp_dma(dev, 0) == -1)
-                return 0;
+            pnp_irq(dev, 0) == -1 && pnp_dma(dev, 0) == -1)
+                return 0;
         else
                 return 1;
 }
 
-
-
 EXPORT_SYMBOL(pnp_is_active);
diff --git a/drivers/pnp/system.c b/drivers/pnp/system.c
index a8a95540b1ef..a06f980b3ac9 100644
--- a/drivers/pnp/system.c
+++ b/drivers/pnp/system.c
@@ -16,13 +16,14 @@
 
 static const struct pnp_device_id pnp_dev_table[] = {
         /* General ID for reserving resources */
-        {       "PNP0c02",              0       },
+        {"PNP0c02", 0},
         /* memory controller */
-        {       "PNP0c01",              0       },
-        {       "",                     0       }
+        {"PNP0c01", 0},
+        {"", 0}
 };
 
-static void reserve_range(const char *pnpid, resource_size_t start, resource_size_t end, int port)
+static void reserve_range(const char *pnpid, resource_size_t start,
+                          resource_size_t end, int port)
 {
         struct resource *res;
         char *regionid;
@@ -32,9 +33,9 @@ static void reserve_range(const char *pnpid, resource_size_t start, resource_siz
                 return;
         snprintf(regionid, 16, "pnp %s", pnpid);
         if (port)
-                res = request_region(start, end-start+1, regionid);
+                res = request_region(start, end - start + 1, regionid);
         else
-                res = request_mem_region(start, end-start+1, regionid);
+                res = request_mem_region(start, end - start + 1, regionid);
         if (res == NULL)
                 kfree(regionid);
         else
@@ -44,11 +45,10 @@ static void reserve_range(const char *pnpid, resource_size_t start, resource_siz
          * example do reserve stuff they know about too, so we may well
          * have double reservations.
          */
-        printk(KERN_INFO
-                "pnp: %s: %s range 0x%llx-0x%llx %s reserved\n",
-                pnpid, port ? "ioport" : "iomem",
-                (unsigned long long)start, (unsigned long long)end,
-                NULL != res ? "has been" : "could not be");
+        printk(KERN_INFO "pnp: %s: %s range 0x%llx-0x%llx %s reserved\n",
+               pnpid, port ? "ioport" : "iomem",
+               (unsigned long long)start, (unsigned long long)end,
+               NULL != res ? "has been" : "could not be");
 }
 
 static void reserve_resources_of_dev(const struct pnp_dev *dev)
@@ -74,7 +74,7 @@ static void reserve_resources_of_dev(const struct pnp_dev *dev)
                         continue;       /* invalid */
 
                 reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
-                        pnp_port_end(dev, i), 1);
+                              pnp_port_end(dev, i), 1);
         }
 
         for (i = 0; i < PNP_MAX_MEM; i++) {
@@ -82,24 +82,22 @@ static void reserve_resources_of_dev(const struct pnp_dev *dev)
                         continue;
 
                 reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
-                        pnp_mem_end(dev, i), 0);
+                              pnp_mem_end(dev, i), 0);
         }
-
-        return;
 }
 
-static int system_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
+static int system_pnp_probe(struct pnp_dev *dev,
+                            const struct pnp_device_id *dev_id)
 {
         reserve_resources_of_dev(dev);
         return 0;
 }
 
 static struct pnp_driver system_pnp_driver = {
-        .name           = "system",
-        .id_table       = pnp_dev_table,
-        .flags          = PNP_DRIVER_RES_DO_NOT_CHANGE,
-        .probe          = system_pnp_probe,
-        .remove         = NULL,
+        .name     = "system",
+        .id_table = pnp_dev_table,
+        .flags    = PNP_DRIVER_RES_DO_NOT_CHANGE,
+        .probe    = system_pnp_probe,
 };
 
 static int __init pnp_system_init(void)
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 7ede9e725360..d3a33aa2696f 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -15,34 +15,36 @@ rtc-core-$(CONFIG_RTC_INTF_DEV)	+= rtc-dev.o
 rtc-core-$(CONFIG_RTC_INTF_PROC) += rtc-proc.o
 rtc-core-$(CONFIG_RTC_INTF_SYSFS) += rtc-sysfs.o
 
+# Keep the list ordered.
+
+obj-$(CONFIG_RTC_DRV_AT32AP700X)+= rtc-at32ap700x.o
+obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
+obj-$(CONFIG_RTC_DRV_BFIN)      += rtc-bfin.o
 obj-$(CONFIG_RTC_DRV_CMOS)      += rtc-cmos.o
-obj-$(CONFIG_RTC_DRV_X1205)     += rtc-x1205.o
-obj-$(CONFIG_RTC_DRV_ISL1208)   += rtc-isl1208.o
-obj-$(CONFIG_RTC_DRV_TEST)      += rtc-test.o
-obj-$(CONFIG_RTC_DRV_AT32AP700X)        += rtc-at32ap700x.o
+obj-$(CONFIG_RTC_DRV_DS1216)    += rtc-ds1216.o
 obj-$(CONFIG_RTC_DRV_DS1307)    += rtc-ds1307.o
+obj-$(CONFIG_RTC_DRV_DS1553)    += rtc-ds1553.o
 obj-$(CONFIG_RTC_DRV_DS1672)    += rtc-ds1672.o
 obj-$(CONFIG_RTC_DRV_DS1742)    += rtc-ds1742.o
+obj-$(CONFIG_RTC_DRV_EP93XX)    += rtc-ep93xx.o
+obj-$(CONFIG_RTC_DRV_ISL1208)   += rtc-isl1208.o
+obj-$(CONFIG_RTC_DRV_M41T80)    += rtc-m41t80.o
+obj-$(CONFIG_RTC_DRV_M48T59)    += rtc-m48t59.o
+obj-$(CONFIG_RTC_DRV_M48T86)    += rtc-m48t86.o
+obj-$(CONFIG_RTC_DRV_MAX6900)   += rtc-max6900.o
+obj-$(CONFIG_RTC_DRV_MAX6902)   += rtc-max6902.o
 obj-$(CONFIG_RTC_DRV_OMAP)      += rtc-omap.o
 obj-$(CONFIG_RTC_DRV_PCF8563)   += rtc-pcf8563.o
 obj-$(CONFIG_RTC_DRV_PCF8583)   += rtc-pcf8583.o
+obj-$(CONFIG_RTC_DRV_PL031)     += rtc-pl031.o
+obj-$(CONFIG_RTC_DRV_RS5C313)   += rtc-rs5c313.o
+obj-$(CONFIG_RTC_DRV_RS5C348)   += rtc-rs5c348.o
 obj-$(CONFIG_RTC_DRV_RS5C372)   += rtc-rs5c372.o
 obj-$(CONFIG_RTC_DRV_S3C)       += rtc-s3c.o
-obj-$(CONFIG_RTC_DRV_RS5C348)   += rtc-rs5c348.o
-obj-$(CONFIG_RTC_DRV_M41T80)    += rtc-m41t80.o
-obj-$(CONFIG_RTC_DRV_M48T86)    += rtc-m48t86.o
-obj-$(CONFIG_RTC_DRV_DS1553)    += rtc-ds1553.o
-obj-$(CONFIG_RTC_DRV_STK17TA8)  += rtc-stk17ta8.o
-obj-$(CONFIG_RTC_DRV_RS5C313)   += rtc-rs5c313.o
-obj-$(CONFIG_RTC_DRV_EP93XX)    += rtc-ep93xx.o
 obj-$(CONFIG_RTC_DRV_SA1100)    += rtc-sa1100.o
-obj-$(CONFIG_RTC_DRV_VR41XX)    += rtc-vr41xx.o
-obj-$(CONFIG_RTC_DRV_PL031)     += rtc-pl031.o
-obj-$(CONFIG_RTC_DRV_MAX6900)   += rtc-max6900.o
-obj-$(CONFIG_RTC_DRV_MAX6902)   += rtc-max6902.o
-obj-$(CONFIG_RTC_DRV_V3020)     += rtc-v3020.o
-obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
 obj-$(CONFIG_RTC_DRV_SH)        += rtc-sh.o
-obj-$(CONFIG_RTC_DRV_BFIN)      += rtc-bfin.o
-obj-$(CONFIG_RTC_DRV_M48T59)    += rtc-m48t59.o
-obj-$(CONFIG_RTC_DRV_DS1216)    += rtc-ds1216.o
+obj-$(CONFIG_RTC_DRV_STK17TA8)  += rtc-stk17ta8.o
+obj-$(CONFIG_RTC_DRV_TEST)      += rtc-test.o
+obj-$(CONFIG_RTC_DRV_V3020)     += rtc-v3020.o
+obj-$(CONFIG_RTC_DRV_VR41XX)    += rtc-vr41xx.o
+obj-$(CONFIG_RTC_DRV_X1205)     += rtc-x1205.o
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 5158a625671f..db6f3f0d8982 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -352,7 +352,7 @@ read_rtc:
                 /* oscillator fault?  clear flag, and warn */
                 if (ds1307->regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
                         i2c_smbus_write_byte_data(client, DS1307_REG_CONTROL,
-                                        ds1307->regs[DS1337_REG_CONTROL]
+                                        ds1307->regs[DS1307_REG_CONTROL]
                                         & ~DS1338_BIT_OSF);
                         dev_warn(&client->dev, "SET TIME!\n");
                         goto read_rtc;
diff --git a/drivers/rtc/rtc-stk17ta8.c b/drivers/rtc/rtc-stk17ta8.c
index f10d3facecbe..8288b6b2bf2b 100644
--- a/drivers/rtc/rtc-stk17ta8.c
+++ b/drivers/rtc/rtc-stk17ta8.c
@@ -258,7 +258,8 @@ static const struct rtc_class_ops stk17ta8_rtc_ops = {
         .ioctl          = stk17ta8_rtc_ioctl,
 };
 
-static ssize_t stk17ta8_nvram_read(struct kobject *kobj, char *buf,
+static ssize_t stk17ta8_nvram_read(struct kobject *kobj,
+                                 struct bin_attribute *attr, char *buf,
                                  loff_t pos, size_t size)
 {
         struct platform_device *pdev =
@@ -272,7 +273,8 @@ static ssize_t stk17ta8_nvram_read(struct kobject *kobj, char *buf,
         return count;
 }
 
-static ssize_t stk17ta8_nvram_write(struct kobject *kobj, char *buf,
+static ssize_t stk17ta8_nvram_write(struct kobject *kobj,
+                                  struct bin_attribute *attr, char *buf,
                                   loff_t pos, size_t size)
 {
         struct platform_device *pdev =
diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index 7071ff8da63e..5cf48123e0ef 100644
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -28,7 +28,7 @@
 #include <asm/hardware.h>
 
 #include <asm/arch/regs-gpio.h>
-#include <asm/arch/regs-spi.h>
+#include <asm/plat-s3c24xx/regs-spi.h>
 #include <asm/arch/spi.h>
 
 struct s3c24xx_spi {
diff --git a/drivers/video/chipsfb.c b/drivers/video/chipsfb.c
index f48e8c534c87..6796ba62c3c6 100644
--- a/drivers/video/chipsfb.c
+++ b/drivers/video/chipsfb.c
@@ -24,6 +24,7 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/fb.h>
+#include <linux/pm.h>
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/console.h>
@@ -458,7 +459,7 @@ static int chipsfb_pci_suspend(struct pci_dev *pdev, pm_message_t state)
 
         if (state.event == pdev->dev.power.power_state.event)
                 return 0;
-        if (state.event != PM_SUSPEND_MEM)
+        if (state.event != PM_EVENT_SUSPEND)
                 goto done;
 
         acquire_console_sem();
diff --git a/drivers/video/tgafb.c b/drivers/video/tgafb.c
index 89facb73edfc..d292a37ec7d6 100644
--- a/drivers/video/tgafb.c
+++ b/drivers/video/tgafb.c
@@ -849,7 +849,7 @@ tgafb_clut_imageblit(struct fb_info *info, const struct fb_image *image)
         u32 *palette = ((u32 *)info->pseudo_palette);
         unsigned long pos, line_length, i, j;
         const unsigned char *data;
-        void *regs_base, *fb_base;
+        void __iomem *regs_base, *fb_base;
 
         dx = image->dx;
         dy = image->dy;
diff --git a/drivers/w1/masters/ds1wm.c b/drivers/w1/masters/ds1wm.c
index 763bc73e5070..4b696641ce33 100644
--- a/drivers/w1/masters/ds1wm.c
+++ b/drivers/w1/masters/ds1wm.c
@@ -85,7 +85,7 @@ static struct {
 };
 
 struct ds1wm_data {
-        void            *map;
+        void            __iomem *map;
         int             bus_shift; /* # of shifts to calc register offsets */
         struct platform_device *pdev;
         struct ds1wm_platform_data *pdata;
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index 9e943fbce81b..227d53b12a5c 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -782,8 +782,8 @@ static int process_msg(void)
                 msg->u.watch.vec = split(body, msg->hdr.len,
                                          &msg->u.watch.vec_size);
                 if (IS_ERR(msg->u.watch.vec)) {
-                        kfree(msg);
                         err = PTR_ERR(msg->u.watch.vec);
+                        kfree(msg);
                         goto out;
                 }
 
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 68579a0ed3f0..639a32c3c9c1 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -580,7 +580,7 @@ static int ext2_check_descriptors (struct super_block * sb)
                         return 0;
                 }
                 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
-                    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
+                    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
                     last_block)
                 {
                         ext2_error (sb, "ext2_check_descriptors",
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index f0614e3f1fe8..22cfdd61c060 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -1221,7 +1221,7 @@ static int ext3_check_descriptors (struct super_block * sb)
                         return 0;
                 }
                 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
-                    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
+                    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
                     last_block)
                 {
                         ext3_error (sb, "ext3_check_descriptors",
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 75adbb64e028..4550b83ab1c9 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1283,7 +1283,7 @@ static int ext4_check_descriptors (struct super_block * sb)
                 }
                 inode_table = ext4_inode_table(sb, gdp);
                 if (inode_table < first_block ||
-                    inode_table + sbi->s_itb_per_group > last_block)
+                    inode_table + sbi->s_itb_per_group - 1 > last_block)
                 {
                         ext4_error (sb, "ext4_check_descriptors",
                                     "Inode table for group %d"
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index b3efa4536cc5..a21e4bc5444b 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -335,10 +335,10 @@ static void nlmsvc_freegrantargs(struct nlm_rqst *call)
 /*
  * Deferred lock request handling for non-blocking lock
  */
-static u32
+static __be32
 nlmsvc_defer_lock_rqst(struct svc_rqst *rqstp, struct nlm_block *block)
 {
-        u32 status = nlm_lck_denied_nolocks;
+        __be32 status = nlm_lck_denied_nolocks;
 
         block->b_flags |= B_QUEUED;
 
@@ -352,7 +352,7 @@ nlmsvc_defer_lock_rqst(struct svc_rqst *rqstp, struct nlm_block *block)
                         status = nlm_drop_reply;
         }
         dprintk("lockd: nlmsvc_defer_lock_rqst block %p flags %d status %d\n",
-                block, block->b_flags, status);
+                block, block->b_flags, ntohl(status));
 
         return status;
 }
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index b3d55c6747fd..8ef0964179bc 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2450,7 +2450,7 @@ nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_
 }
 
 static void
-nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, int nfserr,
+nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
                      struct nfsd4_secinfo *secinfo)
 {
         int i = 0;
diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
index b6f12593c39d..981027d1187b 100644
--- a/fs/reiserfs/stree.c
+++ b/fs/reiserfs/stree.c
@@ -1042,7 +1042,8 @@ static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, st
                 pos = I_UNFM_NUM(&s_ih);
 
                 while (le_ih_k_offset (&s_ih) + (pos - 1) * blk_size > n_new_file_length) {
-                    __u32 *unfm, block;
+                    __le32 *unfm;
+                    __u32 block;
 
                     /* Each unformatted block deletion may involve one additional
                      * bitmap block into the transaction, thereby the initial
@@ -1052,7 +1053,7 @@ static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, st
                         break;
                     }
 
-                    unfm = (__u32 *)B_I_PITEM(p_s_bh, &s_ih) + pos - 1;
+                    unfm = (__le32 *)B_I_PITEM(p_s_bh, &s_ih) + pos - 1;
                     block = get_block_num(unfm, 0);
 
                     if (block != 0) {
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 3b07f26d984d..7b941abbcde0 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -320,7 +320,7 @@ asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemas
 
         if (sizemask != sizeof(sigset_t) ||
             copy_from_user(&sigmask, user_mask, sizeof(sigmask)))
-                return error = -EINVAL;
+                return -EINVAL;
         sigdelsetmask(&sigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
         signotset(&sigmask);
 
diff --git a/fs/timerfd.c b/fs/timerfd.c
index af9eca5c0230..61983f3b107c 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -95,7 +95,7 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
 {
         struct timerfd_ctx *ctx = file->private_data;
         ssize_t res;
-        u32 ticks = 0;
+        u64 ticks = 0;
         DECLARE_WAITQUEUE(wait, current);
 
         if (count < sizeof(ticks))
@@ -130,7 +130,7 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
                          * callback to avoid DoS attacks specifying a very
                          * short timer period.
                          */
-                        ticks = (u32)
+                        ticks = (u64)
                                 hrtimer_forward(&ctx->tmr,
                                                 hrtimer_cb_get_time(&ctx->tmr),
                                                 ctx->tintv);
@@ -140,7 +140,7 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
         }
         spin_unlock_irq(&ctx->wqh.lock);
         if (ticks)
-                res = put_user(ticks, buf) ? -EFAULT: sizeof(ticks);
+                res = put_user(ticks, (u64 __user *) buf) ? -EFAULT: sizeof(ticks);
         return res;
 }
 
diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.c b/fs/xfs/linux-2.6/xfs_ioctl32.c
index 141cf15067c2..42319d75aaab 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl32.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl32.c
@@ -139,7 +139,7 @@ STATIC int xfs_inumbers_fmt_compat(
         long count,
         long *written)
 {
-        compat_xfs_inogrp_t *p32 = ubuffer;
+        compat_xfs_inogrp_t __user *p32 = ubuffer;
         long i;
 
         for (i = 0; i < count; i++) {
@@ -444,7 +444,7 @@ xfs_compat_ioctl(
         case XFS_IOC_FSINUMBERS_32:
                 cmd = _NATIVE_IOC(cmd, struct xfs_fsop_bulkreq);
                 return xfs_ioc_bulkstat_compat(XFS_BHVTOI(VNHEAD(vp))->i_mount,
-                                cmd, (void*)arg);
+                                cmd, (void __user*)arg);
         case XFS_IOC_FD_TO_HANDLE_32:
         case XFS_IOC_PATH_TO_HANDLE_32:
         case XFS_IOC_PATH_TO_FSHANDLE_32:
diff --git a/include/asm-alpha/bitops.h b/include/asm-alpha/bitops.h
index 3a0cbeb03fa1..9e71201000d5 100644
--- a/include/asm-alpha/bitops.h
+++ b/include/asm-alpha/bitops.h
@@ -324,7 +324,7 @@ static inline int fls64(unsigned long x)
 {
         unsigned long t, a, r;
 
-        t = __kernel_cmpbge (x, 0x0101010101010101);
+        t = __kernel_cmpbge (x, 0x0101010101010101UL);
         a = __flsm1_tab[t];
         t = __kernel_extbl (x, a);
         r = a*8 + __flsm1_tab[t] + (x != 0);
diff --git a/include/asm-arm/unaligned.h b/include/asm-arm/unaligned.h
index 795b9e5b9e6a..8431f6eed5c6 100644
--- a/include/asm-arm/unaligned.h
+++ b/include/asm-arm/unaligned.h
@@ -60,24 +60,24 @@ extern int __bug_unaligned_x(const void *ptr);
                 __get_unaligned_4_be((__p+4)))
 
 #define __get_unaligned_le(ptr)                                         \
-        ({                                                              \
+        ((__force typeof(*(ptr)))({                                     \
                 const __u8 *__p = (const __u8 *)(ptr);                  \
                 __builtin_choose_expr(sizeof(*(ptr)) == 1, *__p,        \
                   __builtin_choose_expr(sizeof(*(ptr)) == 2, __get_unaligned_2_le(__p), \
                   __builtin_choose_expr(sizeof(*(ptr)) == 4, __get_unaligned_4_le(__p), \
                   __builtin_choose_expr(sizeof(*(ptr)) == 8, __get_unaligned_8_le(__p), \
                     (void)__bug_unaligned_x(__p)))));                   \
-        })
+        }))
 
 #define __get_unaligned_be(ptr)                                         \
-        ({                                                              \
+        ((__force typeof(*(ptr)))({                                     \
                 const __u8 *__p = (const __u8 *)(ptr);                  \
                 __builtin_choose_expr(sizeof(*(ptr)) == 1, *__p,        \
                   __builtin_choose_expr(sizeof(*(ptr)) == 2, __get_unaligned_2_be(__p), \
                   __builtin_choose_expr(sizeof(*(ptr)) == 4, __get_unaligned_4_be(__p), \
                   __builtin_choose_expr(sizeof(*(ptr)) == 8, __get_unaligned_8_be(__p), \
                     (void)__bug_unaligned_x(__p)))));                   \
-        })
+        }))
 
 
 static inline void __put_unaligned_2_le(__u32 __v, register __u8 *__p)
@@ -131,15 +131,16 @@ static inline void __put_unaligned_8_be(const unsigned long long __v, register _
  */
 #define __put_unaligned_le(val,ptr)                                     \
         ({                                                      \
+                (void)sizeof(*(ptr) = (val));                   \
                 switch (sizeof(*(ptr))) {                       \
                 case 1:                                         \
                         *(ptr) = (val);                         \
                         break;                                  \
-                case 2: __put_unaligned_2_le((val),(__u8 *)(ptr));      \
+                case 2: __put_unaligned_2_le((__force u16)(val),(__u8 *)(ptr)); \
                         break;                                  \
-                case 4: __put_unaligned_4_le((val),(__u8 *)(ptr));      \
+                case 4: __put_unaligned_4_le((__force u32)(val),(__u8 *)(ptr)); \
                         break;                                  \
-                case 8: __put_unaligned_8_le((val),(__u8 *)(ptr)); \
+                case 8: __put_unaligned_8_le((__force u64)(val),(__u8 *)(ptr)); \
                         break;                                  \
                 default: __bug_unaligned_x(ptr);                \
                         break;                                  \
@@ -149,15 +150,16 @@ static inline void __put_unaligned_8_be(const unsigned long long __v, register _
 
 #define __put_unaligned_be(val,ptr)                                     \
         ({                                                      \
+                (void)sizeof(*(ptr) = (val));                   \
                 switch (sizeof(*(ptr))) {                       \
                 case 1:                                         \
                         *(ptr) = (val);                         \
                         break;                                  \
-                case 2: __put_unaligned_2_be((val),(__u8 *)(ptr));      \
+                case 2: __put_unaligned_2_be((__force u16)(val),(__u8 *)(ptr)); \
                         break;                                  \
-                case 4: __put_unaligned_4_be((val),(__u8 *)(ptr));      \
+                case 4: __put_unaligned_4_be((__force u32)(val),(__u8 *)(ptr)); \
                         break;                                  \
-                case 8: __put_unaligned_8_be((val),(__u8 *)(ptr)); \
+                case 8: __put_unaligned_8_be((__force u64)(val),(__u8 *)(ptr)); \
                         break;                                  \
                 default: __bug_unaligned_x(ptr);                \
                         break;                                  \
diff --git a/include/asm-m68k/raw_io.h b/include/asm-m68k/raw_io.h
index 91c623f0994c..d9eb9834ccc8 100644
--- a/include/asm-m68k/raw_io.h
+++ b/include/asm-m68k/raw_io.h
@@ -36,15 +36,15 @@ extern void __iounmap(void *addr, unsigned long size);
 #define in_be32(addr) \
     ({ u32 __v = (*(__force volatile u32 *) (addr)); __v; })
 #define in_le16(addr) \
-    ({ u16 __v = le16_to_cpu(*(__force volatile u16 *) (addr)); __v; })
+    ({ u16 __v = le16_to_cpu(*(__force volatile __le16 *) (addr)); __v; })
 #define in_le32(addr) \
-    ({ u32 __v = le32_to_cpu(*(__force volatile u32 *) (addr)); __v; })
+    ({ u32 __v = le32_to_cpu(*(__force volatile __le32 *) (addr)); __v; })
 
 #define out_8(addr,b) (void)((*(__force volatile u8 *) (addr)) = (b))
 #define out_be16(addr,w) (void)((*(__force volatile u16 *) (addr)) = (w))
 #define out_be32(addr,l) (void)((*(__force volatile u32 *) (addr)) = (l))
-#define out_le16(addr,w) (void)((*(__force volatile u16 *) (addr)) = cpu_to_le16(w))
-#define out_le32(addr,l) (void)((*(__force volatile u32 *) (addr)) = cpu_to_le32(l))
+#define out_le16(addr,w) (void)((*(__force volatile __le16 *) (addr)) = cpu_to_le16(w))
+#define out_le32(addr,l) (void)((*(__force volatile __le32 *) (addr)) = cpu_to_le32(l))
 
 #define raw_inb in_8
 #define raw_inw in_be16
diff --git a/include/asm-m68knommu/hardirq.h b/include/asm-m68knommu/hardirq.h
index 980075bab792..bfad28149a49 100644
--- a/include/asm-m68knommu/hardirq.h
+++ b/include/asm-m68knommu/hardirq.h
@@ -22,4 +22,6 @@ typedef struct {
 # error HARDIRQ_BITS is too low!
 #endif
 
+void ack_bad_irq(unsigned int irq);
+
 #endif /* __M68K_HARDIRQ_H */
diff --git a/include/asm-m68knommu/machdep.h b/include/asm-m68knommu/machdep.h
index 6ce28f8e0ead..2b75a300df4f 100644
--- a/include/asm-m68knommu/machdep.h
+++ b/include/asm-m68knommu/machdep.h
@@ -48,6 +48,5 @@ extern char *mach_sysrq_xlate;
 
 extern void config_BSP(char *command, int len);
 extern void (*mach_tick)(void);
-extern void (*mach_trap_init)(void);
 
 #endif /* _M68KNOMMU_MACHDEP_H */
diff --git a/include/asm-mips/edac.h b/include/asm-mips/edac.h
new file mode 100644
index 000000000000..83719eee2d13
--- /dev/null
+++ b/include/asm-mips/edac.h
@@ -0,0 +1,35 @@
+#ifndef ASM_EDAC_H
+#define ASM_EDAC_H
+
+/* ECC atomic, DMA, SMP and interrupt safe scrub function */
+
+static inline void atomic_scrub(void *va, u32 size)
+{
+        unsigned long *virt_addr = va;
+        unsigned long temp;
+        u32 i;
+
+        for (i = 0; i < size / sizeof(unsigned long); i++, virt_addr++) {
+
+                /*
+                 * Very carefully read and write to memory atomically
+                 * so we are interrupt, DMA and SMP safe.
+                 *
+                 * Intel: asm("lock; addl $0, %0"::"m"(*virt_addr));
+                 */
+
+                __asm__ __volatile__ (
+                "       .set    mips3                                   \n"
+                "1:     ll      %0, %1          # atomic_add            \n"
+                "       ll      %0, %1          # atomic_add            \n"
+                "       addu    %0, $0                                  \n"
+                "       sc      %0, %1                                  \n"
+                "       beqz    %0, 1b                                  \n"
+                "       .set    mips0                                   \n"
+                : "=&r" (temp), "=m" (*virt_addr)
+                : "m" (*virt_addr));
+
+        }
+}
+
+#endif
diff --git a/include/asm-powerpc/bug.h b/include/asm-powerpc/bug.h
index f6fa39474846..a248b8bd4d7c 100644
--- a/include/asm-powerpc/bug.h
+++ b/include/asm-powerpc/bug.h
@@ -79,7 +79,7 @@
                 _EMIT_BUG_ENTRY                                 \
                 : : "i" (__FILE__), "i" (__LINE__), "i" (0),    \
                   "i" (sizeof(struct bug_entry)),               \
-                  "r" ((long)(x)));                             \
+                  "r" ((__force long)(x)));                     \
         }                                                       \
 } while (0)
 
diff --git a/include/asm-powerpc/page.h b/include/asm-powerpc/page.h
index 10c51f457d48..236a9210e5fc 100644
--- a/include/asm-powerpc/page.h
+++ b/include/asm-powerpc/page.h
@@ -190,7 +190,6 @@ extern void copy_user_page(void *to, void *from, unsigned long vaddr,
 extern int page_is_ram(unsigned long pfn);
 
 struct vm_area_struct;
-extern const char *arch_vma_name(struct vm_area_struct *vma);
 
 #include <asm-generic/memory_model.h>
 #endif /* __ASSEMBLY__ */
diff --git a/include/asm-x86_64/uaccess.h b/include/asm-x86_64/uaccess.h
index 9df30b939c4e..f4ce8768ad44 100644
--- a/include/asm-x86_64/uaccess.h
+++ b/include/asm-x86_64/uaccess.h
@@ -100,7 +100,7 @@ struct exception_table_entry
         case 8:  __get_user_x(8,__ret_gu,__val_gu,ptr); break;          \
         default: __get_user_bad(); break;                               \
         }                                                               \
-        (x) = (typeof(*(ptr)))__val_gu;                         \
+        (x) = (__force typeof(*(ptr)))__val_gu;                         \
         __ret_gu;                                                       \
 })
 
@@ -192,7 +192,7 @@ struct __large_struct { unsigned long buf[100]; };
         int __gu_err;                                           \
         unsigned long __gu_val;                                 \
         __get_user_size(__gu_val,(ptr),(size),__gu_err);        \
-        (x) = (typeof(*(ptr)))__gu_val;                 \
+        (x) = (__force typeof(*(ptr)))__gu_val;                 \
         __gu_err;                                               \
 })
 
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 12a1291855e2..86f9a3a6137d 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -15,8 +15,8 @@
 # define __acquire(x)   __context__(x,1)
 # define __release(x)   __context__(x,-1)
 # define __cond_lock(x,c)       ((c) ? ({ __acquire(x); 1; }) : 0)
-extern void __chk_user_ptr(const void __user *);
-extern void __chk_io_ptr(const void __iomem *);
+extern void __chk_user_ptr(const volatile void __user *);
+extern void __chk_io_ptr(const volatile void __iomem *);
 #else
 # define __user
 # define __kernel
diff --git a/include/linux/device.h b/include/linux/device.h
index d9f0a57f5a2f..3a38d1f70cb7 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -551,6 +551,9 @@ extern void put_device(struct device * dev);
 /* drivers/base/power/shutdown.c */
 extern void device_shutdown(void);
 
+/* drivers/base/sys.c */
+extern void sysdev_shutdown(void);
+
 
 /* drivers/base/firmware.c */
 extern int __must_check firmware_register(struct kset *);
diff --git a/include/linux/lguest.h b/include/linux/lguest.h
index 500aace21ca7..e76c151c7129 100644
--- a/include/linux/lguest.h
+++ b/include/linux/lguest.h
@@ -27,18 +27,38 @@
 #define LG_CLOCK_MIN_DELTA      100UL
 #define LG_CLOCK_MAX_DELTA      ULONG_MAX
 
+/*G:031 First, how does our Guest contact the Host to ask for privileged
+ * operations?  There are two ways: the direct way is to make a "hypercall",
+ * to make requests of the Host Itself.
+ *
+ * Our hypercall mechanism uses the highest unused trap code (traps 32 and
+ * above are used by real hardware interrupts).  Seventeen hypercalls are
+ * available: the hypercall number is put in the %eax register, and the
+ * arguments (when required) are placed in %edx, %ebx and %ecx.  If a return
+ * value makes sense, it's returned in %eax.
+ *
+ * Grossly invalid calls result in Sudden Death at the hands of the vengeful
+ * Host, rather than returning failure.  This reflects Winston Churchill's
+ * definition of a gentleman: "someone who is only rude intentionally". */
 #define LGUEST_TRAP_ENTRY 0x1F
 
 static inline unsigned long
 hcall(unsigned long call,
       unsigned long arg1, unsigned long arg2, unsigned long arg3)
 {
+        /* "int" is the Intel instruction to trigger a trap. */
         asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
+                       /* The call is in %eax (aka "a"), and can be replaced */
                      : "=a"(call)
+                       /* The other arguments are in %eax, %edx, %ebx & %ecx */
                      : "a"(call), "d"(arg1), "b"(arg2), "c"(arg3)
+                       /* "memory" means this might write somewhere in memory.
+                        * This isn't true for all calls, but it's safe to tell
+                        * gcc that it might happen so it doesn't get clever. */
                      : "memory");
         return call;
 }
+/*:*/
 
 void async_hcall(unsigned long call,
                  unsigned long arg1, unsigned long arg2, unsigned long arg3);
@@ -52,31 +72,40 @@ struct hcall_ring
         u32 eax, edx, ebx, ecx;
 };
 
-/* All the good stuff happens here: guest registers it with LGUEST_INIT */
+/*G:032 The second method of communicating with the Host is to via "struct
+ * lguest_data".  The Guest's very first hypercall is to tell the Host where
+ * this is, and then the Guest and Host both publish information in it. :*/
 struct lguest_data
 {
-/* Fields which change during running: */
-        /* 512 == enabled (same as eflags) */
+        /* 512 == enabled (same as eflags in normal hardware).  The Guest
+         * changes interrupts so often that a hypercall is too slow. */
         unsigned int irq_enabled;
-        /* Interrupts blocked by guest. */
+        /* Fine-grained interrupt disabling by the Guest */
         DECLARE_BITMAP(blocked_interrupts, LGUEST_IRQS);
 
-        /* Virtual address of page fault. */
+        /* The Host writes the virtual address of the last page fault here,
+         * which saves the Guest a hypercall.  CR2 is the native register where
+         * this address would normally be found. */
         unsigned long cr2;
 
-        /* Async hypercall ring.  0xFF == done, 0 == pending. */
+        /* Async hypercall ring.  Instead of directly making hypercalls, we can
+         * place them in here for processing the next time the Host wants.
+         * This batching can be quite efficient. */
+
+        /* 0xFF == done (set by Host), 0 == pending (set by Guest). */
         u8 hcall_status[LHCALL_RING_SIZE];
+        /* The actual registers for the hypercalls. */
         struct hcall_ring hcalls[LHCALL_RING_SIZE];
 
-/* Fields initialized by the hypervisor at boot: */
+/* Fields initialized by the Host at boot: */
         /* Memory not to try to access */
         unsigned long reserve_mem;
-        /* ID of this guest (used by network driver to set ethernet address) */
+        /* ID of this Guest (used by network driver to set ethernet address) */
         u16 guestid;
         /* KHz for the TSC clock. */
         u32 tsc_khz;
 
-/* Fields initialized by the guest at boot: */
+/* Fields initialized by the Guest at boot: */
         /* Instruction range to suppress interrupts even if enabled */
         unsigned long noirq_start, noirq_end;
 };
diff --git a/include/linux/lguest_bus.h b/include/linux/lguest_bus.h
index c9b4e05fee49..d27853ddc644 100644
--- a/include/linux/lguest_bus.h
+++ b/include/linux/lguest_bus.h
@@ -15,11 +15,14 @@ struct lguest_device {
         void *private;
 };
 
-/* By convention, each device can use irq index+1 if it wants to. */
+/*D:380 Since interrupt numbers are arbitrary, we use a convention: each device
+ * can use the interrupt number corresponding to its index.  The +1 is because
+ * interrupt 0 is not usable (it's actually the timer interrupt). */
 static inline int lgdev_irq(const struct lguest_device *dev)
 {
         return dev->index + 1;
 }
+/*:*/
 
 /* dma args must not be vmalloced! */
 void lguest_send_dma(unsigned long key, struct lguest_dma *dma);
diff --git a/include/linux/lguest_launcher.h b/include/linux/lguest_launcher.h
index 0ba414a40c80..641670579446 100644
--- a/include/linux/lguest_launcher.h
+++ b/include/linux/lguest_launcher.h
@@ -9,14 +9,45 @@
 /* How many devices?  Assume each one wants up to two dma arrays per device. */
 #define LGUEST_MAX_DEVICES (LGUEST_MAX_DMA/2)
 
+/*D:200
+ * Lguest I/O
+ *
+ * The lguest I/O mechanism is the only way Guests can talk to devices.  There
+ * are two hypercalls involved: SEND_DMA for output and BIND_DMA for input.  In
+ * each case, "struct lguest_dma" describes the buffer: this contains 16
+ * addr/len pairs, and if there are fewer buffer elements the len array is
+ * terminated with a 0.
+ *
+ * I/O is organized by keys: BIND_DMA attaches buffers to a particular key, and
+ * SEND_DMA transfers to buffers bound to particular key.  By convention, keys
+ * correspond to a physical address within the device's page.  This means that
+ * devices will never accidentally end up with the same keys, and allows the
+ * Host use The Futex Trick (as we'll see later in our journey).
+ *
+ * SEND_DMA simply indicates a key to send to, and the physical address of the
+ * "struct lguest_dma" to send.  The Host will write the number of bytes
+ * transferred into the "struct lguest_dma"'s used_len member.
+ *
+ * BIND_DMA indicates a key to bind to, a pointer to an array of "struct
+ * lguest_dma"s ready for receiving, the size of that array, and an interrupt
+ * to trigger when data is received.  The Host will only allow transfers into
+ * buffers with a used_len of zero: it then sets used_len to the number of
+ * bytes transferred and triggers the interrupt for the Guest to process the
+ * new input. */
 struct lguest_dma
 {
-        /* 0 if free to be used, filled by hypervisor. */
+        /* 0 if free to be used, filled by the Host. */
         u32 used_len;
         unsigned long addr[LGUEST_MAX_DMA_SECTIONS];
         u16 len[LGUEST_MAX_DMA_SECTIONS];
 };
+/*:*/
 
+/*D:460 This is the layout of a block device memory page.  The Launcher sets up
+ * the num_sectors initially to tell the Guest the size of the disk.  The Guest
+ * puts the type, sector and length of the request in the first three fields,
+ * then DMAs to the Host.  The Host processes the request, sets up the result,
+ * then DMAs back to the Guest. */
 struct lguest_block_page
 {
         /* 0 is a read, 1 is a write. */
@@ -28,27 +59,47 @@ struct lguest_block_page
         u32 num_sectors; /* Disk length = num_sectors * 512 */
 };
 
-/* There is a shared page of these. */
+/*D:520 The network device is basically a memory page where all the Guests on
+ * the network publish their MAC (ethernet) addresses: it's an array of "struct
+ * lguest_net": */
 struct lguest_net
 {
         /* Simply the mac address (with multicast bit meaning promisc). */
         unsigned char mac[6];
 };
+/*:*/
 
 /* Where the Host expects the Guest to SEND_DMA console output to. */
 #define LGUEST_CONSOLE_DMA_KEY 0
 
-/* We have a page of these descriptors in the lguest_device page. */
+/*D:010
+ * Drivers
+ *
+ * The Guest needs devices to do anything useful.  Since we don't let it touch
+ * real devices (think of the damage it could do!) we provide virtual devices.
+ * We could emulate a PCI bus with various devices on it, but that is a fairly
+ * complex burden for the Host and suboptimal for the Guest, so we have our own
+ * "lguest" bus and simple drivers.
+ *
+ * Devices are described by an array of LGUEST_MAX_DEVICES of these structs,
+ * placed by the Launcher just above the top of physical memory:
+ */
 struct lguest_device_desc {
+        /* The device type: console, network, disk etc. */
         u16 type;
 #define LGUEST_DEVICE_T_CONSOLE 1
 #define LGUEST_DEVICE_T_NET     2
 #define LGUEST_DEVICE_T_BLOCK   3
 
+        /* The specific features of this device: these depends on device type
+         * except for LGUEST_DEVICE_F_RANDOMNESS. */
         u16 features;
 #define LGUEST_NET_F_NOCSUM             0x4000 /* Don't bother checksumming */
 #define LGUEST_DEVICE_F_RANDOMNESS      0x8000 /* IRQ is fairly random */
 
+        /* This is how the Guest reports status of the device: the Host can set
+         * LGUEST_DEVICE_S_REMOVED to indicate removal, but the rest are only
+         * ever manipulated by the Guest, and only ever set. */
         u16 status;
 /* 256 and above are device specific. */
 #define LGUEST_DEVICE_S_ACKNOWLEDGE     1 /* We have seen device. */
@@ -58,9 +109,12 @@ struct lguest_device_desc {
 #define LGUEST_DEVICE_S_REMOVED_ACK     16 /* Driver has been told. */
 #define LGUEST_DEVICE_S_FAILED          128 /* Something actually failed */
 
+        /* Each device exists somewhere in Guest physical memory, over some
+         * number of pages. */
         u16 num_pages;
         u32 pfn;
 };
+/*:*/
 
 /* Write command first word is a request. */
 enum lguest_req
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c456c3a1c28e..3e9e8fec5a41 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1246,7 +1246,7 @@ void drop_slab(void);
 extern int randomize_va_space;
 #endif
 
-__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma);
+const char * arch_vma_name(struct vm_area_struct *vma);
 
 #endif /* __KERNEL__ */
 #endif /* _LINUX_MM_H */
diff --git a/include/linux/netfilter/xt_connlimit.h b/include/linux/netfilter/xt_connlimit.h
index 90ae8b474cb8..37e933c9987d 100644
--- a/include/linux/netfilter/xt_connlimit.h
+++ b/include/linux/netfilter/xt_connlimit.h
@@ -5,8 +5,8 @@ struct xt_connlimit_data;
 
 struct xt_connlimit_info {
         union {
-                u_int32_t v4_mask;
-                u_int32_t v6_mask[4];
+                __be32 v4_mask;
+                __be32 v6_mask[4];
         };
         unsigned int limit, inverse;
 
diff --git a/include/linux/pnp.h b/include/linux/pnp.h
index 66edb2293184..16b46aace349 100644
--- a/include/linux/pnp.h
+++ b/include/linux/pnp.h
@@ -1,7 +1,6 @@
 /*
  * Linux Plug and Play Support
  * Copyright by Adam Belay <ambx1@neo.rr.com>
- *
  */
 
 #ifndef _LINUX_PNP_H
@@ -23,7 +22,6 @@
 struct pnp_protocol;
 struct pnp_dev;
 
-
 /*
  * Resource Management
  */
@@ -73,37 +71,37 @@ struct pnp_dev;
 #define PNP_PORT_FLAG_FIXED     (1<<1)
 
 struct pnp_port {
-        unsigned short min;             /* min base number */
-        unsigned short max;             /* max base number */
-        unsigned char align;            /* align boundary */
-        unsigned char size;             /* size of range */
-        unsigned char flags;            /* port flags */
-        unsigned char pad;              /* pad */
-        struct pnp_port *next;          /* next port */
+        unsigned short min;     /* min base number */
+        unsigned short max;     /* max base number */
+        unsigned char align;    /* align boundary */
+        unsigned char size;     /* size of range */
+        unsigned char flags;    /* port flags */
+        unsigned char pad;      /* pad */
+        struct pnp_port *next;  /* next port */
 };
 
 #define PNP_IRQ_NR 256
 struct pnp_irq {
-        DECLARE_BITMAP(map, PNP_IRQ_NR); /* bitmaks for IRQ lines */
-        unsigned char flags;            /* IRQ flags */
-        unsigned char pad;              /* pad */
-        struct pnp_irq *next;           /* next IRQ */
+        DECLARE_BITMAP(map, PNP_IRQ_NR);        /* bitmask for IRQ lines */
+        unsigned char flags;    /* IRQ flags */
+        unsigned char pad;      /* pad */
+        struct pnp_irq *next;   /* next IRQ */
 };
 
 struct pnp_dma {
-        unsigned char map;              /* bitmask for DMA channels */
-        unsigned char flags;            /* DMA flags */
-        struct pnp_dma *next;           /* next port */
+        unsigned char map;      /* bitmask for DMA channels */
+        unsigned char flags;    /* DMA flags */
+        struct pnp_dma *next;   /* next port */
 };
 
 struct pnp_mem {
-        unsigned int min;               /* min base number */
-        unsigned int max;               /* max base number */
-        unsigned int align;             /* align boundary */
-        unsigned int size;              /* size of range */
-        unsigned char flags;            /* memory flags */
-        unsigned char pad;              /* pad */
-        struct pnp_mem *next;           /* next memory resource */
+        unsigned int min;       /* min base number */
+        unsigned int max;       /* max base number */
+        unsigned int align;     /* align boundary */
+        unsigned int size;      /* size of range */
+        unsigned char flags;    /* memory flags */
+        unsigned char pad;      /* pad */
+        struct pnp_mem *next;   /* next memory resource */
 };
 
 #define PNP_RES_PRIORITY_PREFERRED      0
@@ -127,7 +125,6 @@ struct pnp_resource_table {
         struct resource irq_resource[PNP_MAX_IRQ];
 };
 
-
 /*
  * Device Managemnt
  */
@@ -139,14 +136,14 @@ struct pnp_card {
         struct list_head protocol_list; /* node in protocol's list of cards */
         struct list_head devices;       /* devices attached to the card */
 
-        struct pnp_protocol * protocol;
-        struct pnp_id * id;             /* contains supported EISA IDs*/
+        struct pnp_protocol *protocol;
+        struct pnp_id *id;              /* contains supported EISA IDs */
 
         char name[PNP_NAME_LEN];        /* contains a human-readable name */
-        unsigned char   pnpver;         /* Plug & Play version */
-        unsigned char   productver;     /* product version */
-        unsigned int    serial;         /* serial number */
-        unsigned char   checksum;       /* if zero - checksum passed */
+        unsigned char pnpver;           /* Plug & Play version */
+        unsigned char productver;       /* product version */
+        unsigned int serial;            /* serial number */
+        unsigned char checksum;         /* if zero - checksum passed */
         struct proc_dir_entry *procdir; /* directory entry in /proc/bus/isapnp */
 };
 
@@ -159,18 +156,18 @@ struct pnp_card {
         (card) = global_to_pnp_card((card)->global_list.next))
 
 struct pnp_card_link {
-        struct pnp_card * card;
-        struct pnp_card_driver * driver;
-        void * driver_data;
+        struct pnp_card *card;
+        struct pnp_card_driver *driver;
+        void *driver_data;
         pm_message_t pm_state;
 };
 
-static inline void *pnp_get_card_drvdata (struct pnp_card_link *pcard)
+static inline void *pnp_get_card_drvdata(struct pnp_card_link *pcard)
 {
         return pcard->driver_data;
 }
 
-static inline void pnp_set_card_drvdata (struct pnp_card_link *pcard, void *data)
+static inline void pnp_set_card_drvdata(struct pnp_card_link *pcard, void *data)
 {
         pcard->driver_data = data;
 }
@@ -186,22 +183,22 @@ struct pnp_dev {
         struct list_head card_list;     /* node in card's list of devices */
         struct list_head rdev_list;     /* node in cards list of requested devices */
 
-        struct pnp_protocol * protocol;
-        struct pnp_card * card;         /* card the device is attached to, none if NULL */
-        struct pnp_driver * driver;
-        struct pnp_card_link * card_link;
+        struct pnp_protocol *protocol;
+        struct pnp_card *card;  /* card the device is attached to, none if NULL */
+        struct pnp_driver *driver;
+        struct pnp_card_link *card_link;
 
-        struct pnp_id   * id;   /* supported EISA IDs*/
+        struct pnp_id *id;              /* supported EISA IDs */
 
         int active;
         int capabilities;
-        struct pnp_option * independent;
-        struct pnp_option * dependent;
+        struct pnp_option *independent;
+        struct pnp_option *dependent;
         struct pnp_resource_table res;
 
         char name[PNP_NAME_LEN];        /* contains a human-readable name */
-        unsigned short  regs;           /* ISAPnP: supported registers */
-        int             flags;          /* used by protocols */
+        unsigned short regs;            /* ISAPnP: supported registers */
+        int flags;                      /* used by protocols */
         struct proc_dir_entry *procent; /* device entry in /proc/bus/isapnp */
         void *data;
 };
@@ -220,19 +217,19 @@ struct pnp_dev {
         (dev) = card_to_pnp_dev((dev)->card_list.next))
 #define pnp_dev_name(dev) (dev)->name
 
-static inline void *pnp_get_drvdata (struct pnp_dev *pdev)
+static inline void *pnp_get_drvdata(struct pnp_dev *pdev)
 {
         return dev_get_drvdata(&pdev->dev);
 }
 
-static inline void pnp_set_drvdata (struct pnp_dev *pdev, void *data)
+static inline void pnp_set_drvdata(struct pnp_dev *pdev, void *data)
 {
         dev_set_drvdata(&pdev->dev, data);
 }
 
 struct pnp_fixup {
         char id[7];
-        void (*quirk_function)(struct pnp_dev *dev);    /* fixup function */
+        void (*quirk_function) (struct pnp_dev * dev);  /* fixup function */
 };
 
 /* config parameters */
@@ -269,7 +266,6 @@ extern struct pnp_protocol pnpbios_protocol;
 #define pnp_device_is_pnpbios(dev) 0
 #endif
 
-
 /* status */
 #define PNP_READY               0x0000
 #define PNP_ATTACHED            0x0001
@@ -287,17 +283,17 @@ extern struct pnp_protocol pnpbios_protocol;
 
 struct pnp_id {
         char id[PNP_ID_LEN];
-        struct pnp_id * next;
+        struct pnp_id *next;
 };
 
 struct pnp_driver {
-        char * name;
+        char *name;
         const struct pnp_device_id *id_table;
         unsigned int flags;
-        int  (*probe)  (struct pnp_dev *dev, const struct pnp_device_id *dev_id);
+        int (*probe) (struct pnp_dev *dev, const struct pnp_device_id *dev_id);
         void (*remove) (struct pnp_dev *dev);
-        int  (*suspend) (struct pnp_dev *dev, pm_message_t state);
-        int  (*resume) (struct pnp_dev *dev);
+        int (*suspend) (struct pnp_dev *dev, pm_message_t state);
+        int (*resume) (struct pnp_dev *dev);
         struct device_driver driver;
 };
 
@@ -305,13 +301,14 @@ struct pnp_driver {
 
 struct pnp_card_driver {
         struct list_head global_list;
-        char * name;
+        char *name;
         const struct pnp_card_device_id *id_table;
         unsigned int flags;
-        int  (*probe)  (struct pnp_card_link *card, const struct pnp_card_device_id *card_id);
+        int (*probe) (struct pnp_card_link *card,
+                      const struct pnp_card_device_id *card_id);
         void (*remove) (struct pnp_card_link *card);
-        int  (*suspend) (struct pnp_card_link *card, pm_message_t state);
-        int  (*resume) (struct pnp_card_link *card);
+        int (*suspend) (struct pnp_card_link *card, pm_message_t state);
+        int (*resume) (struct pnp_card_link *card);
         struct pnp_driver link;
 };
 
@@ -321,29 +318,28 @@ struct pnp_card_driver {
 #define PNP_DRIVER_RES_DO_NOT_CHANGE    0x0001  /* do not change the state of the device */
 #define PNP_DRIVER_RES_DISABLE          0x0003  /* ensure the device is disabled */
 
-
 /*
  * Protocol Management
  */
 
 struct pnp_protocol {
-        struct list_head        protocol_list;
-        char                  * name;
+        struct list_head protocol_list;
+        char *name;
 
         /* resource control functions */
-        int (*get)(struct pnp_dev *dev, struct pnp_resource_table *res);
-        int (*set)(struct pnp_dev *dev, struct pnp_resource_table *res);
-        int (*disable)(struct pnp_dev *dev);
+        int (*get) (struct pnp_dev *dev, struct pnp_resource_table *res);
+        int (*set) (struct pnp_dev *dev, struct pnp_resource_table *res);
+        int (*disable) (struct pnp_dev *dev);
 
         /* protocol specific suspend/resume */
-        int (*suspend)(struct pnp_dev *dev, pm_message_t state);
-        int (*resume)(struct pnp_dev *dev);
+        int (*suspend) (struct pnp_dev * dev, pm_message_t state);
+        int (*resume) (struct pnp_dev * dev);
 
         /* used by pnp layer only (look but don't touch) */
-        unsigned char           number;         /* protocol number*/
-        struct device           dev;            /* link to driver model */
-        struct list_head        cards;
-        struct list_head        devices;
+        unsigned char number;   /* protocol number */
+        struct device dev;      /* link to driver model */
+        struct list_head cards;
+        struct list_head devices;
 };
 
 #define to_pnp_protocol(n) list_entry(n, struct pnp_protocol, protocol_list)
@@ -356,7 +352,6 @@ struct pnp_protocol {
         (dev) != protocol_to_pnp_dev(&(protocol)->devices); \
         (dev) = protocol_to_pnp_dev((dev)->protocol_list.next))
 
-
 extern struct bus_type pnp_bus_type;
 
 #if defined(CONFIG_PNP)
@@ -376,21 +371,25 @@ void pnp_remove_card(struct pnp_card *card);
 int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev);
 void pnp_remove_card_device(struct pnp_dev *dev);
 int pnp_add_card_id(struct pnp_id *id, struct pnp_card *card);
-struct pnp_dev * pnp_request_card_device(struct pnp_card_link *clink, const char * id, struct pnp_dev * from);
-void pnp_release_card_device(struct pnp_dev * dev);
-int pnp_register_card_driver(struct pnp_card_driver * drv);
-void pnp_unregister_card_driver(struct pnp_card_driver * drv);
+struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink,
+                                        const char *id, struct pnp_dev *from);
+void pnp_release_card_device(struct pnp_dev *dev);
+int pnp_register_card_driver(struct pnp_card_driver *drv);
+void pnp_unregister_card_driver(struct pnp_card_driver *drv);
 extern struct list_head pnp_cards;
 
 /* resource management */
-struct pnp_option * pnp_register_independent_option(struct pnp_dev *dev);
-struct pnp_option * pnp_register_dependent_option(struct pnp_dev *dev, int priority);
+struct pnp_option *pnp_register_independent_option(struct pnp_dev *dev);
+struct pnp_option *pnp_register_dependent_option(struct pnp_dev *dev,
+                                                 int priority);
 int pnp_register_irq_resource(struct pnp_option *option, struct pnp_irq *data);
 int pnp_register_dma_resource(struct pnp_option *option, struct pnp_dma *data);
-int pnp_register_port_resource(struct pnp_option *option, struct pnp_port *data);
+int pnp_register_port_resource(struct pnp_option *option,
+                               struct pnp_port *data);
 int pnp_register_mem_resource(struct pnp_option *option, struct pnp_mem *data);
 void pnp_init_resource_table(struct pnp_resource_table *table);
-int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res, int mode);
+int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res,
+                          int mode);
 int pnp_auto_config_dev(struct pnp_dev *dev);
 int pnp_validate_config(struct pnp_dev *dev);
 int pnp_start_dev(struct pnp_dev *dev);
@@ -398,11 +397,11 @@ int pnp_stop_dev(struct pnp_dev *dev);
 int pnp_activate_dev(struct pnp_dev *dev);
 int pnp_disable_dev(struct pnp_dev *dev);
 void pnp_resource_change(struct resource *resource, resource_size_t start,
-                                resource_size_t size);
+                         resource_size_t size);
 
 /* protocol helpers */
-int pnp_is_active(struct pnp_dev * dev);
-int compare_pnp_id(struct pnp_id * pos, const char * id);
+int pnp_is_active(struct pnp_dev *dev);
+int compare_pnp_id(struct pnp_id *pos, const char *id);
 int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev);
 int pnp_register_driver(struct pnp_driver *drv);
 void pnp_unregister_driver(struct pnp_driver *drv);
@@ -415,23 +414,24 @@ static inline void pnp_unregister_protocol(struct pnp_protocol *protocol) { }
 static inline int pnp_init_device(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_add_device(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_device_attach(struct pnp_dev *pnp_dev) { return -ENODEV; }
-static inline void pnp_device_detach(struct pnp_dev *pnp_dev) { ; }
+static inline void pnp_device_detach(struct pnp_dev *pnp_dev) { }
+
 #define pnp_platform_devices 0
 
 /* multidevice card support */
 static inline int pnp_add_card(struct pnp_card *card) { return -ENODEV; }
-static inline void pnp_remove_card(struct pnp_card *card) { ; }
+static inline void pnp_remove_card(struct pnp_card *card) { }
 static inline int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev) { return -ENODEV; }
-static inline void pnp_remove_card_device(struct pnp_dev *dev) { ; }
+static inline void pnp_remove_card_device(struct pnp_dev *dev) { }
 static inline int pnp_add_card_id(struct pnp_id *id, struct pnp_card *card) { return -ENODEV; }
-static inline struct pnp_dev * pnp_request_card_device(struct pnp_card_link *clink, const char * id, struct pnp_dev * from) { return NULL; }
-static inline void pnp_release_card_device(struct pnp_dev * dev) { ; }
-static inline int pnp_register_card_driver(struct pnp_card_driver * drv) { return -ENODEV; }
-static inline void pnp_unregister_card_driver(struct pnp_card_driver * drv) { ; }
+static inline struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink, const char *id, struct pnp_dev *from) { return NULL; }
+static inline void pnp_release_card_device(struct pnp_dev *dev) { }
+static inline int pnp_register_card_driver(struct pnp_card_driver *drv) { return -ENODEV; }
+static inline void pnp_unregister_card_driver(struct pnp_card_driver *drv) { }
 
 /* resource management */
-static inline struct pnp_option * pnp_register_independent_option(struct pnp_dev *dev) { return NULL; }
-static inline struct pnp_option * pnp_register_dependent_option(struct pnp_dev *dev, int priority) { return NULL; }
+static inline struct pnp_option *pnp_register_independent_option(struct pnp_dev *dev) { return NULL; }
+static inline struct pnp_option *pnp_register_dependent_option(struct pnp_dev *dev, int priority) { return NULL; }
 static inline int pnp_register_irq_resource(struct pnp_option *option, struct pnp_irq *data) { return -ENODEV; }
 static inline int pnp_register_dma_resource(struct pnp_option *option, struct pnp_dma *data) { return -ENODEV; }
 static inline int pnp_register_port_resource(struct pnp_option *option, struct pnp_port *data) { return -ENODEV; }
@@ -444,20 +444,17 @@ static inline int pnp_start_dev(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_stop_dev(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_activate_dev(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_disable_dev(struct pnp_dev *dev) { return -ENODEV; }
-static inline void pnp_resource_change(struct resource *resource,
-                                        resource_size_t start,
-                                        resource_size_t size) { }
+static inline void pnp_resource_change(struct resource *resource, resource_size_t start, resource_size_t size) { }
 
 /* protocol helpers */
-static inline int pnp_is_active(struct pnp_dev * dev) { return 0; }
-static inline int compare_pnp_id(struct pnp_id * pos, const char * id) { return -ENODEV; }
+static inline int pnp_is_active(struct pnp_dev *dev) { return 0; }
+static inline int compare_pnp_id(struct pnp_id *pos, const char *id) { return -ENODEV; }
 static inline int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_register_driver(struct pnp_driver *drv) { return -ENODEV; }
-static inline void pnp_unregister_driver(struct pnp_driver *drv) { ; }
+static inline void pnp_unregister_driver(struct pnp_driver *drv) { }
 
 #endif /* CONFIG_PNP */
 
-
 #define pnp_err(format, arg...) printk(KERN_ERR "pnp: " format "\n" , ## arg)
 #define pnp_info(format, arg...) printk(KERN_INFO "pnp: " format "\n" , ## arg)
 #define pnp_warn(format, arg...) printk(KERN_WARNING "pnp: " format "\n" , ## arg)
diff --git a/include/linux/pnpbios.h b/include/linux/pnpbios.h
index 0a282ac1f6b2..329192adc9dd 100644
--- a/include/linux/pnpbios.h
+++ b/include/linux/pnpbios.h
@@ -99,32 +99,32 @@
 
 #pragma pack(1)
 struct pnp_dev_node_info {
-        __u16   no_nodes;
-        __u16   max_node_size;
+        __u16 no_nodes;
+        __u16 max_node_size;
 };
 struct pnp_docking_station_info {
-        __u32   location_id;
-        __u32   serial;
-        __u16   capabilities;
+        __u32 location_id;
+        __u32 serial;
+        __u16 capabilities;
 };
 struct pnp_isa_config_struc {
-        __u8    revision;
-        __u8    no_csns;
-        __u16   isa_rd_data_port;
-        __u16   reserved;
+        __u8 revision;
+        __u8 no_csns;
+        __u16 isa_rd_data_port;
+        __u16 reserved;
 };
 struct escd_info_struc {
-        __u16   min_escd_write_size;
-        __u16   escd_size;
-        __u32   nv_storage_base;
+        __u16 min_escd_write_size;
+        __u16 escd_size;
+        __u32 nv_storage_base;
 };
 struct pnp_bios_node {
-        __u16   size;
-        __u8    handle;
-        __u32   eisa_id;
-        __u8    type_code[3];
-        __u16   flags;
-        __u8    data[0];
+        __u16 size;
+        __u8 handle;
+        __u32 eisa_id;
+        __u8 type_code[3];
+        __u16 flags;
+        __u8 data[0];
 };
 #pragma pack()
 
@@ -133,22 +133,16 @@ struct pnp_bios_node {
 /* non-exported */
 extern struct pnp_dev_node_info node_info;
 
-extern int pnp_bios_dev_node_info (struct pnp_dev_node_info *data);
-extern int pnp_bios_get_dev_node (u8 *nodenum, char config, struct pnp_bios_node *data);
-extern int pnp_bios_set_dev_node (u8 nodenum, char config, struct pnp_bios_node *data);
-extern int pnp_bios_get_stat_res (char *info);
-extern int pnp_bios_isapnp_config (struct pnp_isa_config_struc *data);
-extern int pnp_bios_escd_info (struct escd_info_struc *data);
-extern int pnp_bios_read_escd (char *data, u32 nvram_base);
+extern int pnp_bios_dev_node_info(struct pnp_dev_node_info *data);
+extern int pnp_bios_get_dev_node(u8 *nodenum, char config,
+                                 struct pnp_bios_node *data);
+extern int pnp_bios_set_dev_node(u8 nodenum, char config,
+                                 struct pnp_bios_node *data);
+extern int pnp_bios_get_stat_res(char *info);
+extern int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data);
+extern int pnp_bios_escd_info(struct escd_info_struc *data);
+extern int pnp_bios_read_escd(char *data, u32 nvram_base);
 extern int pnp_bios_dock_station_info(struct pnp_docking_station_info *data);
-#define needed 0
-#if needed
-extern int pnp_bios_get_event (u16 *message);
-extern int pnp_bios_send_message (u16 message);
-extern int pnp_bios_set_stat_res (char *info);
-extern int pnp_bios_apm_id_table (char *table, u16 *size);
-extern int pnp_bios_write_escd (char *data, u32 nvram_base);
-#endif
 
 #endif /* CONFIG_PNPBIOS */
 
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index e8e6da394c92..618f93c32b7f 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -125,6 +125,9 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 static inline void register_nosave_region(unsigned long b, unsigned long e)
 {
 }
+static inline void register_nosave_region_late(unsigned long b, unsigned long e)
+{
+}
 #endif
 
 #endif /* _LINUX_SWSUSP_H */
diff --git a/include/net/netfilter/nf_conntrack_tuple.h b/include/net/netfilter/nf_conntrack_tuple.h
index 040dae5f0c9e..c48e390f4b0f 100644
--- a/include/net/netfilter/nf_conntrack_tuple.h
+++ b/include/net/netfilter/nf_conntrack_tuple.h
@@ -35,7 +35,7 @@ union nf_conntrack_address {
 union nf_conntrack_man_proto
 {
         /* Add other protocols here. */
-        u_int16_t all;
+        __be16 all;
 
         struct {
                 __be16 port;
@@ -73,7 +73,7 @@ struct nf_conntrack_tuple
                 union nf_conntrack_address u3;
                 union {
                         /* Add other protocols here. */
-                        u_int16_t all;
+                        __be16 all;
 
                         struct {
                                 __be16 port;
diff --git a/include/xen/page.h b/include/xen/page.h
index 1df6c1930578..c0c8fcb27899 100644
--- a/include/xen/page.h
+++ b/include/xen/page.h
@@ -4,6 +4,7 @@
 #include <linux/pfn.h>
 
 #include <asm/uaccess.h>
+#include <asm/pgtable.h>
 
 #include <xen/features.h>
 
diff --git a/init/initramfs.c b/init/initramfs.c
index 00eff7a11085..1db02a0025db 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -133,7 +133,7 @@ static __initdata loff_t this_header, next_header;
 
 static __initdata int dry_run;
 
-static inline void eat(unsigned n)
+static inline void __init eat(unsigned n)
 {
         victim += n;
         this_header += n;
diff --git a/kernel/kmod.c b/kernel/kmod.c
index beedbdc64608..9809cc1f33d6 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -351,11 +351,11 @@ static inline void register_pm_notifier_callback(void) {}
 
 /**
  * call_usermodehelper_setup - prepare to call a usermode helper
- * @path - path to usermode executable
- * @argv - arg vector for process
- * @envp - environment for process
+ * @path: path to usermode executable
+ * @argv: arg vector for process
+ * @envp: environment for process
  *
- * Returns either NULL on allocation failure, or a subprocess_info
+ * Returns either %NULL on allocation failure, or a subprocess_info
  * structure.  This should be passed to call_usermodehelper_exec to
  * exec the process and free the structure.
  */
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 324ac0188ce1..eb72255b5c86 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -216,6 +216,7 @@ int hibernation_platform_enter(void)
                  * sleep state after all
                  */
                 error = hibernation_ops->prepare();
+                sysdev_shutdown();
                 if (!error)
                         error = hibernation_ops->enter();
         } else {
diff --git a/kernel/sys.c b/kernel/sys.c
index 08562f419768..14f8adcfffd9 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -804,6 +804,7 @@ static void kernel_restart_prepare(char *cmd)
         blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
         system_state = SYSTEM_RESTART;
         device_shutdown();
+        sysdev_shutdown();
 }
 
 /**
@@ -860,6 +861,7 @@ void kernel_shutdown_prepare(enum system_states state)
 void kernel_halt(void)
 {
         kernel_shutdown_prepare(SYSTEM_HALT);
+        sysdev_shutdown();
         printk(KERN_EMERG "System halted.\n");
         machine_halt();
 }
@@ -876,6 +878,7 @@ void kernel_power_off(void)
         kernel_shutdown_prepare(SYSTEM_POWER_OFF);
         if (pm_power_off_prepare)
                 pm_power_off_prepare();
+        sysdev_shutdown();
         printk(KERN_EMERG "Power down.\n");
         machine_power_off();
 }
diff --git a/mm/migrate.c b/mm/migrate.c
index 34d8ada053e4..37c73b902008 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -49,9 +49,8 @@ int isolate_lru_page(struct page *page, struct list_head *pagelist)
                 struct zone *zone = page_zone(page);
 
                 spin_lock_irq(&zone->lru_lock);
-                if (PageLRU(page)) {
+                if (PageLRU(page) && get_page_unless_zero(page)) {
                         ret = 0;
-                        get_page(page);
                         ClearPageLRU(page);
                         if (PageActive(page))
                                 del_page_from_active_list(zone, page);
@@ -632,18 +631,35 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
                         goto unlock;
                 wait_on_page_writeback(page);
         }
-
         /*
-         * Establish migration ptes or remove ptes
+         * By try_to_unmap(), page->mapcount goes down to 0 here. In this case,
+         * we cannot notice that anon_vma is freed while we migrates a page.
+         * This rcu_read_lock() delays freeing anon_vma pointer until the end
+         * of migration. File cache pages are no problem because of page_lock()
+         */
+        rcu_read_lock();
+        /*
+         * This is a corner case handling.
+         * When a new swap-cache is read into, it is linked to LRU
+         * and treated as swapcache but has no rmap yet.
+         * Calling try_to_unmap() against a page->mapping==NULL page is
+         * BUG. So handle it here.
          */
+        if (!page->mapping)
+                goto rcu_unlock;
+        /* Establish migration ptes or remove ptes */
         try_to_unmap(page, 1);
+
         if (!page_mapped(page))
                 rc = move_to_new_page(newpage, page);
 
         if (rc)
                 remove_migration_ptes(page, page);
+rcu_unlock:
+        rcu_read_unlock();
 
 unlock:
+
         unlock_page(page);
 
         if (rc != -EAGAIN) {
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 40954fb81598..6d3550ca0282 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2775,11 +2775,11 @@ unsigned long __meminit __absent_pages_in_range(int nid,
         if (i == -1)
                 return 0;
 
+        prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
+
         /* Account for ranges before physical memory on this node */
         if (early_node_map[i].start_pfn > range_start_pfn)
-                hole_pages = early_node_map[i].start_pfn - range_start_pfn;
-
-        prev_end_pfn = early_node_map[i].start_pfn;
+                hole_pages = prev_end_pfn - range_start_pfn;
 
         /* Find all holes for the zone within the node */
         for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 420bbb9955e9..5c18595b7616 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -112,9 +112,9 @@ static int br_handle_local_finish(struct sk_buff *skb)
  */
 static inline int is_link_local(const unsigned char *dest)
 {
-        const u16 *a = (const u16 *) dest;
-        static const u16 *const b = (const u16 *const ) br_group_address;
-        static const u16 m = __constant_cpu_to_be16(0xfff0);
+        __be16 *a = (__be16 *)dest;
+        static const __be16 *b = (const __be16 *)br_group_address;
+        static const __be16 m = __constant_cpu_to_be16(0xfff0);
 
         return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
 }
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c
index e848d8d6292f..deab27facbad 100644
--- a/net/ipv4/netfilter/nf_nat_core.c
+++ b/net/ipv4/netfilter/nf_nat_core.c
@@ -77,7 +77,8 @@ static inline unsigned int
 hash_by_src(const struct nf_conntrack_tuple *tuple)
 {
         /* Original src, to ensure we map it consistently if poss. */
-        return jhash_3words((__force u32)tuple->src.u3.ip, tuple->src.u.all,
+        return jhash_3words((__force u32)tuple->src.u3.ip,
+                            (__force u32)tuple->src.u.all,
                             tuple->dst.protonum, 0) % nf_nat_htable_size;
 }
 
diff --git a/net/ipv4/netfilter/nf_nat_rule.c b/net/ipv4/netfilter/nf_nat_rule.c
index 0f45427e5fdc..76ec59ae524d 100644
--- a/net/ipv4/netfilter/nf_nat_rule.c
+++ b/net/ipv4/netfilter/nf_nat_rule.c
@@ -192,7 +192,7 @@ alloc_null_binding_confirmed(struct nf_conn *ct, unsigned int hooknum)
                 = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC
                    ? ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip
                    : ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip);
-        u_int16_t all
+        __be16 all
                 = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC
                    ? ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.all
                    : ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.all);
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index df30976f6dfd..ca774d8e3be3 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -385,7 +385,7 @@ parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
 
 static int
 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
-            int *type, int *code, int *msg, __be32 *info, int offset)
+            int *type, int *code, int *msg, __u32 *info, int offset)
 {
         struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data;
         struct ip6_tnl *t;
@@ -435,7 +435,7 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
                 if ((*code) == ICMPV6_HDR_FIELD)
                         teli = parse_tlv_tnl_enc_lim(skb, skb->data);
 
-                if (teli && teli == ntohl(*info) - 2) {
+                if (teli && teli == *info - 2) {
                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
                         if (tel->encap_limit == 0) {
                                 if (net_ratelimit())
@@ -452,7 +452,7 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
                 }
                 break;
         case ICMPV6_PKT_TOOBIG:
-                mtu = ntohl(*info) - offset;
+                mtu = *info - offset;
                 if (mtu < IPV6_MIN_MTU)
                         mtu = IPV6_MIN_MTU;
                 t->dev->mtu = mtu;
@@ -478,12 +478,12 @@ out:
 
 static int
 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
-           int type, int code, int offset, __u32 info)
+           int type, int code, int offset, __be32 info)
 {
         int rel_msg = 0;
         int rel_type = type;
         int rel_code = code;
-        __u32 rel_info = info;
+        __u32 rel_info = ntohl(info);
         int err;
         struct sk_buff *skb2;
         struct iphdr *eiph;
@@ -564,10 +564,9 @@ ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
                         goto out;
 
                 skb2->dst->ops->update_pmtu(skb2->dst, rel_info);
-                rel_info = htonl(rel_info);
         }
 
-        icmp_send(skb2, rel_type, rel_code, rel_info);
+        icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 
 out:
         kfree_skb(skb2);
@@ -576,12 +575,12 @@ out:
 
 static int
 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
-           int type, int code, int offset, __u32 info)
+           int type, int code, int offset, __be32 info)
 {
         int rel_msg = 0;
         int rel_type = type;
         int rel_code = code;
-        __u32 rel_info = info;
+        __u32 rel_info = ntohl(info);
         int err;
 
         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
diff --git a/net/key/af_key.c b/net/key/af_key.c
index 0f8304b0246b..7b0a95abe934 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2540,7 +2540,7 @@ static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
         sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
         sel.sport = ((struct sockaddr_in *)(sa + 1))->sin_port;
         if (sel.sport)
-                sel.sport_mask = ~0;
+                sel.sport_mask = htons(0xffff);
 
         /* set destination address info of selector */
         sa = ext_hdrs[SADB_EXT_ADDRESS_DST - 1],
@@ -2549,7 +2549,7 @@ static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
         sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
         sel.dport = ((struct sockaddr_in *)(sa + 1))->sin_port;
         if (sel.dport)
-                sel.dport_mask = ~0;
+                sel.dport_mask = htons(0xffff);
 
         rq = (struct sadb_x_ipsecrequest *)(pol + 1);
 
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index aa086c83af80..0fe11889ce14 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -79,7 +79,8 @@ static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
         a = jhash2(tuple->src.u3.all, ARRAY_SIZE(tuple->src.u3.all),
                    (tuple->src.l3num << 16) | tuple->dst.protonum);
         b = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),
-                   (tuple->src.u.all << 16) | tuple->dst.u.all);
+                   ((__force __u16)tuple->src.u.all << 16) |
+                    (__force __u16)tuple->dst.u.all);
 
         return jhash_2words(a, b, rnd) % size;
 }
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 1aa6229ca99f..eb6695dcd73b 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -80,7 +80,7 @@ static unsigned int nf_ct_expect_dst_hash(const struct nf_conntrack_tuple *tuple
 
         return jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),
                       (((tuple->dst.protonum ^ tuple->src.l3num) << 16) |
-                       tuple->dst.u.all) ^ nf_ct_expect_hash_rnd) %
+                       (__force __u16)tuple->dst.u.all) ^ nf_ct_expect_hash_rnd) %
                nf_ct_expect_hsize;
 }
 
@@ -259,8 +259,8 @@ void nf_ct_expect_init(struct nf_conntrack_expect *exp, int family,
         }
 
         if (src) {
-                exp->tuple.src.u.all = (__force u16)*src;
-                exp->mask.src.u.all = 0xFFFF;
+                exp->tuple.src.u.all = *src;
+                exp->mask.src.u.all = htons(0xFFFF);
         } else {
                 exp->tuple.src.u.all = 0;
                 exp->mask.src.u.all = 0;
@@ -272,7 +272,7 @@ void nf_ct_expect_init(struct nf_conntrack_expect *exp, int family,
                 memset((void *)&exp->tuple.dst.u3 + len, 0x00,
                        sizeof(exp->tuple.dst.u3) - len);
 
-        exp->tuple.dst.u.all = (__force u16)*dst;
+        exp->tuple.dst.u.all = *dst;
 }
 EXPORT_SYMBOL_GPL(nf_ct_expect_init);
 
diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
index ca10df40784f..96aa637c0932 100644
--- a/net/netfilter/nf_conntrack_helper.c
+++ b/net/netfilter/nf_conntrack_helper.c
@@ -39,7 +39,7 @@ static int nf_ct_helper_vmalloc;
 static unsigned int helper_hash(const struct nf_conntrack_tuple *tuple)
 {
         return (((tuple->src.l3num << 8) | tuple->dst.protonum) ^
-                tuple->src.u.all) % nf_ct_helper_hsize;
+                (__force __u16)tuple->src.u.all) % nf_ct_helper_hsize;
 }
 
 struct nf_conntrack_helper *
diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c
index 3335dd5be962..06cff1d13690 100644
--- a/net/netfilter/xt_connlimit.c
+++ b/net/netfilter/xt_connlimit.c
@@ -42,13 +42,13 @@ struct xt_connlimit_data {
 static u_int32_t connlimit_rnd;
 static bool connlimit_rnd_inited;
 
-static inline unsigned int connlimit_iphash(u_int32_t addr)
+static inline unsigned int connlimit_iphash(__be32 addr)
 {
         if (unlikely(!connlimit_rnd_inited)) {
                 get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
                 connlimit_rnd_inited = true;
         }
-        return jhash_1word(addr, connlimit_rnd) & 0xFF;
+        return jhash_1word((__force __u32)addr, connlimit_rnd) & 0xFF;
 }
 
 static inline unsigned int
@@ -66,7 +66,7 @@ connlimit_iphash6(const union nf_conntrack_address *addr,
         for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i)
                 res.ip6[i] = addr->ip6[i] & mask->ip6[i];
 
-        return jhash2(res.ip6, ARRAY_SIZE(res.ip6), connlimit_rnd) & 0xFF;
+        return jhash2((u32 *)res.ip6, ARRAY_SIZE(res.ip6), connlimit_rnd) & 0xFF;
 }
 
 static inline bool already_closed(const struct nf_conn *conn)
diff --git a/net/netfilter/xt_u32.c b/net/netfilter/xt_u32.c
index 04b677ae8dae..74f9b14c012f 100644
--- a/net/netfilter/xt_u32.c
+++ b/net/netfilter/xt_u32.c
@@ -21,6 +21,7 @@ static bool u32_match_it(const struct xt_u32 *data,
         unsigned int nnums;
         unsigned int nvals;
         unsigned int i;
+        __be32 n;
         u_int32_t pos;
         u_int32_t val;
         u_int32_t at;
@@ -38,9 +39,9 @@ static bool u32_match_it(const struct xt_u32 *data,
                 if (skb->len < 4 || pos > skb->len - 4);
                         return false;
 
-                ret   = skb_copy_bits(skb, pos, &val, sizeof(val));
+                ret   = skb_copy_bits(skb, pos, &n, sizeof(n));
                 BUG_ON(ret < 0);
-                val   = ntohl(val);
+                val   = ntohl(n);
                 nnums = ct->nnums;
 
                 /* Inner loop runs over "&", "<<", ">>" and "@" operands */
@@ -65,10 +66,10 @@ static bool u32_match_it(const struct xt_u32 *data,
                                     pos > skb->len - at - 4)
                                         return false;
 
-                                ret = skb_copy_bits(skb, at + pos, &val,
-                                                    sizeof(val));
+                                ret = skb_copy_bits(skb, at + pos, &n,
+                                                    sizeof(n));
                                 BUG_ON(ret < 0);
-                                val = ntohl(val);
+                                val = ntohl(n);
                                 break;
                         }
                 }
diff --git a/net/rxrpc/ar-connection.c b/net/rxrpc/ar-connection.c
index 372b24466dc7..d6667f7bc85e 100644
--- a/net/rxrpc/ar-connection.c
+++ b/net/rxrpc/ar-connection.c
@@ -71,7 +71,7 @@ struct rxrpc_conn_bundle *rxrpc_get_bundle(struct rxrpc_sock *rx,
         struct rb_node *p, *parent, **pp;
 
         _enter("%p{%x},%x,%hx,",
-               rx, key_serial(key), trans->debug_id, ntohl(service_id));
+               rx, key_serial(key), trans->debug_id, ntohs(service_id));
 
         if (rx->trans == trans && rx->bundle) {
                 atomic_inc(&rx->bundle->usage);
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 64b9b8c743c4..12ff5da8160e 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -131,13 +131,13 @@ static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len)
         case AF_INET:
                 snprintf(buf, len, "%u.%u.%u.%u, port=%u",
                         NIPQUAD(((struct sockaddr_in *) addr)->sin_addr),
-                        htons(((struct sockaddr_in *) addr)->sin_port));
+                        ntohs(((struct sockaddr_in *) addr)->sin_port));
                 break;
 
         case AF_INET6:
                 snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u",
                         NIP6(((struct sockaddr_in6 *) addr)->sin6_addr),
-                        htons(((struct sockaddr_in6 *) addr)->sin6_port));
+                        ntohs(((struct sockaddr_in6 *) addr)->sin6_port));
                 break;
 
         default:
diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index 35d5ba1d4f42..ce2659836374 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -72,10 +72,8 @@ static inline void msg_set_bits(struct tipc_msg *m, u32 w,
                                 u32 pos, u32 mask, u32 val)
 {
         val = (val & mask) << pos;
-        val = htonl(val);
-        mask = htonl(mask << pos);
-        m->hdr[w] &= ~mask;
-        m->hdr[w] |= val;
+        m->hdr[w] &= ~htonl(mask << pos);
+        m->hdr[w] |= htonl(val);
 }
 
 /*