Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc vfs updates from Al Viro:
 "All kinds of stuff.  That probably should've been 5 or 6 separate
  branches, but by the time I'd realized how large and mixed that bag
  had become it had been too close to -final to play with rebasing.

  Some fs/namei.c cleanups there, memdup_user_nul() introduction and
  switching open-coded instances, burying long-dead code, whack-a-mole
  of various kinds, several new helpers for ->llseek(), assorted
  cleanups and fixes from various people, etc.

  One piece probably deserves special mention - Neil's
  lookup_one_len_unlocked().  Similar to lookup_one_len(), but gets
  called without ->i_mutex and tries to avoid ever taking it.  That, of
  course, means that it's not useful for any directory modifications,
  but things like getting inode attributes in nfds readdirplus are fine
  with that.  I really should've asked for moratorium on lookup-related
  changes this cycle, but since I hadn't done that early enough...  I
  *am* asking for that for the coming cycle, though - I'm going to try
  and get conversion of i_mutex to rwsem with ->lookup() done under lock
  taken shared.

  There will be a patch closer to the end of the window, along the lines
  of the one Linus had posted last May - mechanical conversion of
  ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/
  inode_is_locked()/inode_lock_nested().  To quote Linus back then:

    -----
    |    This is an automated patch using
    |
    |        sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/'
    |        sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/'
    |        sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[     ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/'
    |        sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/'
    |        sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/'
    |
    |    with a very few manual fixups
    -----

  I'm going to send that once the ->i_mutex-affecting stuff in -next
  gets mostly merged (or when Linus says he's about to stop taking
  merges)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  nfsd: don't hold i_mutex over userspace upcalls
  fs:affs:Replace time_t with time64_t
  fs/9p: use fscache mutex rather than spinlock
  proc: add a reschedule point in proc_readfd_common()
  logfs: constify logfs_block_ops structures
  fcntl: allow to set O_DIRECT flag on pipe
  fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE
  fs: xattr: Use kvfree()
  [s390] page_to_phys() always returns a multiple of PAGE_SIZE
  nbd: use ->compat_ioctl()
  fs: use block_device name vsprintf helper
  lib/vsprintf: add %*pg format specifier
  fs: use gendisk->disk_name where possible
  poll: plug an unused argument to do_poll
  amdkfd: don't open-code memdup_user()
  cdrom: don't open-code memdup_user()
  rsxx: don't open-code memdup_user()
  mtip32xx: don't open-code memdup_user()
  [um] mconsole: don't open-code memdup_user_nul()
  [um] hostaudio: don't open-code memdup_user()
  ...

4 files changed, 10 insertions, 88 deletions

diff --git a/drivers/char/generic_nvram.c b/drivers/char/generic_nvram.c
index 6c4f4b5a9dd3..073db9558379 100644
--- a/drivers/char/generic_nvram.c
+++ b/drivers/char/generic_nvram.c
@@ -20,6 +20,7 @@
 #include <linux/fcntl.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
+#include <linux/pagemap.h>
 #include <asm/uaccess.h>
 #include <asm/nvram.h>
 #ifdef CONFIG_PPC_PMAC
@@ -33,24 +34,8 @@ static ssize_t nvram_len;
 
 static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
 {
-        switch (origin) {
-        case 0:
-                break;
-        case 1:
-                offset += file->f_pos;
-                break;
-        case 2:
-                offset += nvram_len;
-                break;
-        default:
-                offset = -1;
-        }
-        if (offset < 0)
-                return -EINVAL;
-
-        file->f_pos = offset;
-
-        return file->f_pos;
+        return generic_file_llseek_size(file, offset, origin,
+                                        MAX_LFS_FILESIZE, nvram_len);
 }
 
 static ssize_t read_nvram(struct file *file, char __user *buf,
diff --git a/drivers/char/mbcs.c b/drivers/char/mbcs.c
index e5d3e3f7a49b..67d426470e53 100644
--- a/drivers/char/mbcs.c
+++ b/drivers/char/mbcs.c
@@ -26,6 +26,7 @@
 #include <linux/uio.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/pagemap.h>
 #include <asm/io.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -451,31 +452,8 @@ mbcs_sram_write(struct file * fp, const char __user *buf, size_t len, loff_t * o
 
 static loff_t mbcs_sram_llseek(struct file * filp, loff_t off, int whence)
 {
-        loff_t newpos;
-
-        switch (whence) {
-        case SEEK_SET:
-                newpos = off;
-                break;
-
-        case SEEK_CUR:
-                newpos = filp->f_pos + off;
-                break;
-
-        case SEEK_END:
-                newpos = MBCS_SRAM_SIZE + off;
-                break;
-
-        default:                /* can't happen */
-                return -EINVAL;
-        }
-
-        if (newpos < 0)
-                return -EINVAL;
-
-        filp->f_pos = newpos;
-
-        return newpos;
+        return generic_file_llseek_size(filp, off, whence, MAX_LFS_FILESIZE,
+                                        MBCS_SRAM_SIZE);
 }
 
 static uint64_t mbcs_pioaddr(struct mbcs_soft *soft, uint64_t offset)
diff --git a/drivers/char/nvram.c b/drivers/char/nvram.c
index 97c2d8d433d6..01292328a456 100644
--- a/drivers/char/nvram.c
+++ b/drivers/char/nvram.c
@@ -110,6 +110,7 @@
 #include <linux/io.h>
 #include <linux/uaccess.h>
 #include <linux/mutex.h>
+#include <linux/pagemap.h>
 
 
 static DEFINE_MUTEX(nvram_mutex);
@@ -213,21 +214,8 @@ void nvram_set_checksum(void)
 
 static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
 {
-        switch (origin) {
-        case 0:
-                /* nothing to do */
-                break;
-        case 1:
-                offset += file->f_pos;
-                break;
-        case 2:
-                offset += NVRAM_BYTES;
-                break;
-        default:
-                return -EINVAL;
-        }
-
-        return (offset >= 0) ? (file->f_pos = offset) : -EINVAL;
+        return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
+                                        NVRAM_BYTES);
 }
 
 static ssize_t nvram_read(struct file *file, char __user *buf,
diff --git a/drivers/char/nwflash.c b/drivers/char/nwflash.c
index e371480d3639..dbe598de9b74 100644
--- a/drivers/char/nwflash.c
+++ b/drivers/char/nwflash.c
@@ -277,36 +277,7 @@ static loff_t flash_llseek(struct file *file, loff_t offset, int orig)
                 printk(KERN_DEBUG "flash_llseek: offset=0x%X, orig=0x%X.\n",
                        (unsigned int) offset, orig);
 
-        switch (orig) {
-        case 0:
-                if (offset < 0) {
-                        ret = -EINVAL;
-                        break;
-                }
-
-                if ((unsigned int) offset > gbFlashSize) {
-                        ret = -EINVAL;
-                        break;
-                }
-
-                file->f_pos = (unsigned int) offset;
-                ret = file->f_pos;
-                break;
-        case 1:
-                if ((file->f_pos + offset) > gbFlashSize) {
-                        ret = -EINVAL;
-                        break;
-                }
-                if ((file->f_pos + offset) < 0) {
-                        ret = -EINVAL;
-                        break;
-                }
-                file->f_pos += offset;
-                ret = file->f_pos;
-                break;
-        default:
-                ret = -EINVAL;
-        }
+        ret = no_seek_end_llseek_size(file, offset, orig, gbFlashSize);
         mutex_unlock(&flash_mutex);
         return ret;
 }