Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs update from Al Viro:

 - big one - consolidation of descriptor-related logics; almost all of
   that is moved to fs/file.c

   (BTW, I'm seriously tempted to rename the result to fd.c.  As it is,
   we have a situation when file_table.c is about handling of struct
   file and file.c is about handling of descriptor tables; the reasons
   are historical - file_table.c used to be about a static array of
   struct file we used to have way back).

   A lot of stray ends got cleaned up and converted to saner primitives,
   disgusting mess in android/binder.c is still disgusting, but at least
   doesn't poke so much in descriptor table guts anymore.  A bunch of
   relatively minor races got fixed in process, plus an ext4 struct file
   leak.

 - related thing - fget_light() partially unuglified; see fdget() in
   there (and yes, it generates the code as good as we used to have).

 - also related - bits of Cyrill's procfs stuff that got entangled into
   that work; _not_ all of it, just the initial move to fs/proc/fd.c and
   switch of fdinfo to seq_file.

 - Alex's fs/coredump.c spiltoff - the same story, had been easier to
   take that commit than mess with conflicts.  The rest is a separate
   pile, this was just a mechanical code movement.

 - a few misc patches all over the place.  Not all for this cycle,
   there'll be more (and quite a few currently sit in akpm's tree)."

Fix up trivial conflicts in the android binder driver, and some fairly
simple conflicts due to two different changes to the sock_alloc_file()
interface ("take descriptor handling from sock_alloc_file() to callers"
vs "net: Providing protocol type via system.sockprotoname xattr of
/proc/PID/fd entries" adding a dentry name to the socket)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits)
  MAX_LFS_FILESIZE should be a loff_t
  compat: fs: Generic compat_sys_sendfile implementation
  fs: push rcu_barrier() from deactivate_locked_super() to filesystems
  btrfs: reada_extent doesn't need kref for refcount
  coredump: move core dump functionality into its own file
  coredump: prevent double-free on an error path in core dumper
  usb/gadget: fix misannotations
  fcntl: fix misannotations
  ceph: don't abuse d_delete() on failure exits
  hypfs: ->d_parent is never NULL or negative
  vfs: delete surplus inode NULL check
  switch simple cases of fget_light to fdget
  new helpers: fdget()/fdput()
  switch o2hb_region_dev_write() to fget_light()
  proc_map_files_readdir(): don't bother with grabbing files
  make get_file() return its argument
  vhost_set_vring(): turn pollstart/pollstop into bool
  switch prctl_set_mm_exe_file() to fget_light()
  switch xfs_find_handle() to fget_light()
  switch xfs_swapext() to fget_light()
  ...

5 files changed, 39 insertions, 72 deletions

diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 559ae1ee6706..840838769853 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -189,7 +189,7 @@ SYSCALL_SPU(getcwd)
 SYSCALL_SPU(capget)
 SYSCALL_SPU(capset)
 COMPAT_SYS(sigaltstack)
-SYSX_SPU(sys_sendfile64,compat_sys_sendfile,sys_sendfile)
+SYSX_SPU(sys_sendfile,compat_sys_sendfile_wrapper,sys_sendfile)
 SYSCALL(ni_syscall)
 SYSCALL(ni_syscall)
 PPC_SYS(vfork)
@@ -229,7 +229,7 @@ COMPAT_SYS_SPU(sched_setaffinity)
 COMPAT_SYS_SPU(sched_getaffinity)
 SYSCALL(ni_syscall)
 SYSCALL(ni_syscall)
-SYS32ONLY(sendfile64)
+SYSX(sys_ni_syscall,compat_sys_sendfile64_wrapper,sys_sendfile64)
 COMPAT_SYS_SPU(io_setup)
 SYSCALL_SPU(io_destroy)
 COMPAT_SYS_SPU(io_getevents)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index bd377a368611..c683fa350add 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -419,6 +419,7 @@
 #define __ARCH_WANT_COMPAT_SYS_TIME
 #define __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_SYS_NEWFSTATAT
+#define __ARCH_WANT_COMPAT_SYS_SENDFILE
 #endif
 
 /*
diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c
index 81c570633ead..abd1112da54f 100644
--- a/arch/powerpc/kernel/sys_ppc32.c
+++ b/arch/powerpc/kernel/sys_ppc32.c
@@ -143,48 +143,17 @@ long compat_sys_ipc(u32 call, u32 first, u32 second, u32 third, compat_uptr_t pt
  * proper conversion (sign extension) between the register representation of a signed int (msr in 32-bit mode)
  * and the register representation of a signed int (msr in 64-bit mode) is performed.
  */
-asmlinkage long compat_sys_sendfile(u32 out_fd, u32 in_fd, compat_off_t __user * offset, u32 count)
+asmlinkage long compat_sys_sendfile_wrapper(u32 out_fd, u32 in_fd,
+                                            compat_off_t __user *offset, u32 count)
 {
-        mm_segment_t old_fs = get_fs();
-        int ret;
-        off_t of;
-        off_t __user *up;
-
-        if (offset && get_user(of, offset))
-                return -EFAULT;
-
-        /* The __user pointer cast is valid because of the set_fs() */          
-        set_fs(KERNEL_DS);
-        up = offset ? (off_t __user *) &of : NULL;
-        ret = sys_sendfile((int)out_fd, (int)in_fd, up, count);
-        set_fs(old_fs);
-        
-        if (offset && put_user(of, offset))
-                return -EFAULT;
-                
-        return ret;
+        return compat_sys_sendfile((int)out_fd, (int)in_fd, offset, count);
 }
 
-asmlinkage int compat_sys_sendfile64(int out_fd, int in_fd, compat_loff_t __user *offset, s32 count)
+asmlinkage long compat_sys_sendfile64_wrapper(u32 out_fd, u32 in_fd,
+                                              compat_loff_t __user *offset, u32 count)
 {
-        mm_segment_t old_fs = get_fs();
-        int ret;
-        loff_t lof;
-        loff_t __user *up;
-        
-        if (offset && get_user(lof, offset))
-                return -EFAULT;
-                
-        /* The __user pointer cast is valid because of the set_fs() */          
-        set_fs(KERNEL_DS);
-        up = offset ? (loff_t __user *) &lof : NULL;
-        ret = sys_sendfile64(out_fd, in_fd, up, count);
-        set_fs(old_fs);
-        
-        if (offset && put_user(lof, offset))
-                return -EFAULT;
-                
-        return ret;
+        return sys_sendfile((int)out_fd, (int)in_fd,
+                            (off_t __user *)offset, count);
 }
 
 long compat_sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
diff --git a/arch/powerpc/platforms/cell/spu_syscalls.c b/arch/powerpc/platforms/cell/spu_syscalls.c
index 714bbfc3162c..db4e638cf408 100644
--- a/arch/powerpc/platforms/cell/spu_syscalls.c
+++ b/arch/powerpc/platforms/cell/spu_syscalls.c
@@ -69,8 +69,6 @@ SYSCALL_DEFINE4(spu_create, const char __user *, name, unsigned int, flags,
         umode_t, mode, int, neighbor_fd)
 {
         long ret;
-        struct file *neighbor;
-        int fput_needed;
         struct spufs_calls *calls;
 
         calls = spufs_calls_get();
@@ -78,11 +76,11 @@ SYSCALL_DEFINE4(spu_create, const char __user *, name, unsigned int, flags,
                 return -ENOSYS;
 
         if (flags & SPU_CREATE_AFFINITY_SPU) {
+                struct fd neighbor = fdget(neighbor_fd);
                 ret = -EBADF;
-                neighbor = fget_light(neighbor_fd, &fput_needed);
-                if (neighbor) {
-                        ret = calls->create_thread(name, flags, mode, neighbor);
-                        fput_light(neighbor, fput_needed);
+                if (neighbor.file) {
+                        ret = calls->create_thread(name, flags, mode, neighbor.file);
+                        fdput(neighbor);
                 }
         } else
                 ret = calls->create_thread(name, flags, mode, NULL);
@@ -94,8 +92,7 @@ SYSCALL_DEFINE4(spu_create, const char __user *, name, unsigned int, flags,
 asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
 {
         long ret;
-        struct file *filp;
-        int fput_needed;
+        struct fd arg;
         struct spufs_calls *calls;
 
         calls = spufs_calls_get();
@@ -103,10 +100,10 @@ asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
                 return -ENOSYS;
 
         ret = -EBADF;
-        filp = fget_light(fd, &fput_needed);
-        if (filp) {
-                ret = calls->spu_run(filp, unpc, ustatus);
-                fput_light(filp, fput_needed);
+        arg = fdget(fd);
+        if (arg.file) {
+                ret = calls->spu_run(arg.file, unpc, ustatus);
+                fdput(arg);
         }
 
         spufs_calls_put(calls);
diff --git a/arch/powerpc/platforms/cell/spufs/coredump.c b/arch/powerpc/platforms/cell/spufs/coredump.c
index c2c5b078ba80..657e3f233a64 100644
--- a/arch/powerpc/platforms/cell/spufs/coredump.c
+++ b/arch/powerpc/platforms/cell/spufs/coredump.c
@@ -106,6 +106,17 @@ static int spufs_ctx_note_size(struct spu_context *ctx, int dfd)
         return total;
 }
 
+static int match_context(const void *v, struct file *file, unsigned fd)
+{
+        struct spu_context *ctx;
+        if (file->f_op != &spufs_context_fops)
+                return 0;
+        ctx = SPUFS_I(file->f_dentry->d_inode)->i_ctx;
+        if (ctx->flags & SPU_CREATE_NOSCHED)
+                return 0;
+        return fd + 1;
+}
+
 /*
  * The additional architecture-specific notes for Cell are various
  * context files in the spu context.
@@ -115,29 +126,18 @@ static int spufs_ctx_note_size(struct spu_context *ctx, int dfd)
  * internal functionality to dump them without needing to actually
  * open the files.
  */
+/*
+ * descriptor table is not shared, so files can't change or go away.
+ */
 static struct spu_context *coredump_next_context(int *fd)
 {
-        struct fdtable *fdt = files_fdtable(current->files);
         struct file *file;
-        struct spu_context *ctx = NULL;
-
-        for (; *fd < fdt->max_fds; (*fd)++) {
-                if (!fd_is_open(*fd, fdt))
-                        continue;
-
-                file = fcheck(*fd);
-
-                if (!file || file->f_op != &spufs_context_fops)
-                        continue;
-
-                ctx = SPUFS_I(file->f_dentry->d_inode)->i_ctx;
-                if (ctx->flags & SPU_CREATE_NOSCHED)
-                        continue;
-
-                break;
-        }
-
-        return ctx;
+        int n = iterate_fd(current->files, *fd, match_context, NULL);
+        if (!n)
+                return NULL;
+        *fd = n - 1;
+        file = fcheck(*fd);
+        return SPUFS_I(file->f_dentry->d_inode)->i_ctx;
 }
 
 int spufs_coredump_extra_notes_size(void)