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()
  ...

2 files changed, 14 insertions, 100 deletions

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index b1937ca1357..7b0ba92e7e4 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -362,71 +362,22 @@ struct binder_transaction {
 static void
 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
 
-/*
- * copied from get_unused_fd_flags
- */
 static int task_get_unused_fd_flags(struct binder_proc *proc, int flags)
 {
 	struct files_struct *files = proc->files;
-	int fd, error;
-	struct fdtable *fdt;
 	unsigned long rlim_cur;
 	unsigned long irqs;
 
 	if (files == NULL)
 		return -ESRCH;
 
-	error = -EMFILE;
-	spin_lock(&files->file_lock);
-
-repeat:
-	fdt = files_fdtable(files);
-	fd = find_next_zero_bit(fdt->open_fds, fdt->max_fds, files->next_fd);
-
-	/*
-	 * N.B. For clone tasks sharing a files structure, this test
-	 * will limit the total number of files that can be opened.
-	 */
-	rlim_cur = 0;
-	if (lock_task_sighand(proc->tsk, &irqs)) {
-		rlim_cur = proc->tsk->signal->rlim[RLIMIT_NOFILE].rlim_cur;
-		unlock_task_sighand(proc->tsk, &irqs);
-	}
-	if (fd >= rlim_cur)
-		goto out;
-
-	/* Do we need to expand the fd array or fd set?  */
-	error = expand_files(files, fd);
-	if (error < 0)
-		goto out;
-
-	if (error) {
-		/*
-		 * If we needed to expand the fs array we
-		 * might have blocked - try again.
-		 */
-		error = -EMFILE;
-		goto repeat;
-	}
-
-	__set_open_fd(fd, fdt);
-	if (flags & O_CLOEXEC)
-		__set_close_on_exec(fd, fdt);
-	else
-		__clear_close_on_exec(fd, fdt);
-	files->next_fd = fd + 1;
-
-	/* Sanity check */
-	if (fdt->fd[fd] != NULL) {
-		pr_warn("get_unused_fd: slot %d not NULL!\n", fd);
-		fdt->fd[fd] = NULL;
-	}
+	if (!lock_task_sighand(proc->tsk, &irqs))
+		return -EMFILE;
 
-	error = fd;
+	rlim_cur = task_rlimit(proc->tsk, RLIMIT_NOFILE);
+	unlock_task_sighand(proc->tsk, &irqs);
 
-out:
-	spin_unlock(&files->file_lock);
-	return error;
+	return __alloc_fd(files, 0, rlim_cur, flags);
 }
 
 /*
@@ -435,28 +386,8 @@ out:
 static void task_fd_install(
 	struct binder_proc *proc, unsigned int fd, struct file *file)
 {
-	struct files_struct *files = proc->files;
-	struct fdtable *fdt;
-
-	if (files == NULL)
-		return;
-
-	spin_lock(&files->file_lock);
-	fdt = files_fdtable(files);
-	BUG_ON(fdt->fd[fd] != NULL);
-	rcu_assign_pointer(fdt->fd[fd], file);
-	spin_unlock(&files->file_lock);
-}
-
-/*
- * copied from __put_unused_fd in open.c
- */
-static void __put_unused_fd(struct files_struct *files, unsigned int fd)
-{
-	struct fdtable *fdt = files_fdtable(files);
-	__clear_open_fd(fd, fdt);
-	if (fd < files->next_fd)
-		files->next_fd = fd;
+	if (proc->files)
+		__fd_install(proc->files, fd, file);
 }
 
 /*
@@ -464,27 +395,12 @@ static void __put_unused_fd(struct files_struct *files, unsigned int fd)
  */
 static long task_close_fd(struct binder_proc *proc, unsigned int fd)
 {
-	struct file *filp;
-	struct files_struct *files = proc->files;
-	struct fdtable *fdt;
 	int retval;
 
-	if (files == NULL)
+	if (proc->files == NULL)
 		return -ESRCH;
 
-	spin_lock(&files->file_lock);
-	fdt = files_fdtable(files);
-	if (fd >= fdt->max_fds)
-		goto out_unlock;
-	filp = fdt->fd[fd];
-	if (!filp)
-		goto out_unlock;
-	rcu_assign_pointer(fdt->fd[fd], NULL);
-	__clear_close_on_exec(fd, fdt);
-	__put_unused_fd(files, fd);
-	spin_unlock(&files->file_lock);
-	retval = filp_close(filp, files);
-
+	retval = __close_fd(proc->files, fd);
 	/* can't restart close syscall because file table entry was cleared */
 	if (unlikely(retval == -ERESTARTSYS ||
 		     retval == -ERESTARTNOINTR ||
@@ -493,10 +409,6 @@ static long task_close_fd(struct binder_proc *proc, unsigned int fd)
 		retval = -EINTR;
 
 	return retval;
-
-out_unlock:
-	spin_unlock(&files->file_lock);
-	return -EBADF;
 }
 
 static void binder_set_nice(long nice)
@@ -2793,6 +2705,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	const char *failure_string;
 	struct binder_buffer *buffer;
 
+	if (proc->tsk != current)
+		return -EINVAL;
+
 	if ((vma->vm_end - vma->vm_start) > SZ_4M)
 		vma->vm_end = vma->vm_start + SZ_4M;
 
@@ -2857,7 +2772,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	binder_insert_free_buffer(proc, buffer);
 	proc->free_async_space = proc->buffer_size / 2;
 	barrier();
-	proc->files = get_files_struct(proc->tsk);
+	proc->files = get_files_struct(current);
 	proc->vma = vma;
 	proc->vma_vm_mm = vma->vm_mm;
 
diff --git a/drivers/staging/omapdrm/omap_gem.c b/drivers/staging/omapdrm/omap_gem.c
index c8287438e0d..3434e6ec014 100644
--- a/drivers/staging/omapdrm/omap_gem.c
+++ b/drivers/staging/omapdrm/omap_gem.c
@@ -592,9 +592,8 @@ int omap_gem_mmap_obj(struct drm_gem_object *obj,
 		 * in particular in the case of mmap'd dmabufs)
 		 */
 		fput(vma->vm_file);
-		get_file(obj->filp);
 		vma->vm_pgoff = 0;
-		vma->vm_file  = obj->filp;
+		vma->vm_file  = get_file(obj->filp);
 
 		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 	}