...which just returns -EBUSY if a directory alias would be created.

This is to be used by fuse mkdir to make sure that a buggy or malicious
userspace filesystem doesn't do anything nasty.  Previously fuse used a
private mutex for this purpose, which can now go away.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Instead of passing the direction as argument (and checking it on every
step through the hash chain), just have separate __lookup_mnt() and
__lookup_mnt_last().  And use the standard iterators...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

aka br_write_{lock,unlock} of vfsmount_lock.  Inlines in fs/mount.h,
vfsmount_lock extern moved over there as well.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

wake_up_interruptible/poll_wait provide sufficient barriers;
just use ACCESS_ONCE() to fetch ns->event and that's it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

should've been done 6 years ago...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

->mnt_expire is protected by namespace_sem
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

MNT_WRITER_UNDERFLOW_LIMIT has been missed 4 years ago when it became unused.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... and don't bother with dropping and regaining vfsmount_lock
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mnt_list is protected by namespace_sem, not vfsmount_lock
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

nobody else will see that struct file after return from ->release()
anyway; just leave ->f_op as is and let __fput() do that fops_put().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... rather than open-coding it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

duplicated to hell and back...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... on anything found via ->d_fsdata
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

If the underlying dentry doesn't have ->d_revalidate(), there's no need to
force dropping out of RCU mode.  All we need for that is to make freeing
ecryptfs_dentry_info RCU-delayed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Modify the code to use current_euid(), and in_egroup_p, as in done
in fs/proc/proc_sysctl.c:test_perm()

Cc: stable@vger.kernel.org
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull SCSI target fixes from Nicholas Bellinger:
 "Here are the outstanding target fixes queued up for v3.12-rc4 code.

  The highlights include:

   - Make vhost/scsi tag percpu_ida_alloc() use GFP_ATOMIC
   - Allow sess_cmd_map allocation failure fallback to use vzalloc
   - Fix COMPARE_AND_WRITE se_cmd->data_length bug with FILEIO backends
   - Fixes for COMPARE_AND_WRITE callback recursive failure OOPs + non
     zero scsi_status bug
   - Make iscsi-target do acknowledgement tag release from RX context
   - Setup iscsi-target with extra (cmdsn_depth / 2) percpu_ida tags

  Also included is a iscsi-target patch CC'ed for v3.10+ that avoids
  legacy wait_for_task=true release during fast-past StatSN
  acknowledgement, and two other SRP target related patches that address
  long-standing issues that are CC'ed for v3.3+.

  Extra thanks to Thomas Glanzmann for his testing feedback with
  COMPARE_AND_WRITE + EXTENDED_COPY VAAI logic"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  iscsi-target; Allow an extra tag_num / 2 number of percpu_ida tags
  iscsi-target: Perform release of acknowledged tags from RX context
  iscsi-target: Only perform wait_for_tasks when performing shutdown
  target: Fail on non zero scsi_status in compare_and_write_callback
  target: Fix recursive COMPARE_AND_WRITE callback failure
  target: Reset data_length for COMPARE_AND_WRITE to NoLB * block_size
  ib_srpt: always set response for task management
  target: Fall back to vzalloc upon ->sess_cmd_map kzalloc failure
  vhost/scsi: Use GFP_ATOMIC with percpu_ida_alloc for obtaining tag
  ib_srpt: Destroy cm_id before destroying QP.
  target: Fix xop->dbl assignment in target_xcopy_parse_segdesc_02

Pull slave-dmaengine fixes from Vinod Koul:
 "Here is the slave dmanegine fixes.  We have the fix for deadlock issue
  on imx-dma by Michael and Josh's edma config fix along with author
  change"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: imx-dma: fix callback path in tasklet
  dmaengine: imx-dma: fix lockdep issue between irqhandler and tasklet
  dmaengine: imx-dma: fix slow path issue in prep_dma_cyclic
  dma/Kconfig: Make TI_EDMA select TI_PRIV_EDMA
  edma: Update author email address

Pull btrfs fixes from Chris Mason:
 "This is a small collection of fixes, including a regression fix from
  Liu Bo that solves rare crashes with compression on.

  I've merged my for-linus up to 3.12-rc3 because the top commit is only
  meant for 3.12.  The rest of the fixes are also available in my master
  branch on top of my last 3.11 based pull"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: Fix crash due to not allocating integrity data for a bioset
  Btrfs: fix a use-after-free bug in btrfs_dev_replace_finishing
  Btrfs: eliminate races in worker stopping code
  Btrfs: fix crash of compressed writes
  Btrfs: fix transid verify errors when recovering log tree