Pull vfs update from Al Viro:

 - misc stable fixes

 - trivial kernel-doc and comment fixups

 - remove never-used block_page_mkwrite() wrapper function, and rename
   the function that is _actually_ used to not have double underscores.

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: 9p: cache.h: Add #define of include guard
  vfs: remove stale comment in inode_operations
  vfs: remove unused wrapper block_page_mkwrite()
  binfmt_elf: Correct `arch_check_elf's description
  fs: fix writeback.c kernel-doc warnings
  fs: fix inode.c kernel-doc warning
  fs/pipe.c: return error code rather than 0 in pipe_write()
  fs/pipe.c: preserve alloc_file() error code
  binfmt_elf: Don't clobber passed executable's file header
  FS-Cache: Handle a write to the page immediately beyond the EOF marker
  cachefiles: perform test on s_blocksize when opening cache file.
  FS-Cache: Don't override netfs's primary_index if registering failed
  FS-Cache: Increase reference of parent after registering, netfs success
  debugfs: fix refcount imbalance in start_creating

The big warning comment that is currently at the end of struct
inode_operations was added as part of this commit:

4aa7c6346be3 ("vfs: add i_op->dentry_open()")

It was added to warn people not to use the newly added 'dentry_open'
function pointer.

This function pointer was removed as part of this commit:

4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and
		f_inode to the underlay")

The comment was left behind and now refers to nothing, so remove it.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull block IO poll support from Jens Axboe:
 "Various groups have been doing experimentation around IO polling for
  (really) fast devices.  The code has been reviewed and has been
  sitting on the side for a few releases, but this is now good enough
  for coordinated benchmarking and further experimentation.

  Currently O_DIRECT sync read/write are supported.  A framework is in
  the works that allows scalable stats tracking so we can auto-tune
  this.  And we'll add libaio support as well soon.  Fow now, it's an
  opt-in feature for test purposes"

* 'for-4.4/io-poll' of git://git.kernel.dk/linux-block:
  direct-io: be sure to assign dio->bio_bdev for both paths
  directio: add block polling support
  NVMe: add blk polling support
  block: add block polling support
  blk-mq: return tag/queue combo in the make_request_fn handlers
  block: change ->make_request_fn() and users to return a queue cookie

No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.

Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>

Merge patch-bomb from Andrew Morton:

 - inotify tweaks

 - some ocfs2 updates (many more are awaiting review)

 - various misc bits

 - kernel/watchdog.c updates

 - Some of mm.  I have a huge number of MM patches this time and quite a
   lot of it is quite difficult and much will be held over to next time.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
  selftests: vm: add tests for lock on fault
  mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage
  mm: introduce VM_LOCKONFAULT
  mm: mlock: add new mlock system call
  mm: mlock: refactor mlock, munlock, and munlockall code
  kasan: always taint kernel on report
  mm, slub, kasan: enable user tracking by default with KASAN=y
  kasan: use IS_ALIGNED in memory_is_poisoned_8()
  kasan: Fix a type conversion error
  lib: test_kasan: add some testcases
  kasan: update reference to kasan prototype repo
  kasan: move KASAN_SANITIZE in arch/x86/boot/Makefile
  kasan: various fixes in documentation
  kasan: update log messages
  kasan: accurately determine the type of the bad access
  kasan: update reported bug types for kernel memory accesses
  kasan: update reported bug types for not user nor kernel memory accesses
  mm/kasan: prevent deadlock in kasan reporting
  mm/kasan: don't use kasan shadow pointer in generic functions
  mm/kasan: MODULE_VADDR is not available on all archs
  ...

filemap_fdatawait() is a function to wait for on-going writeback to
complete but also consume and clear error status of the mapping set during
writeback.

The latter functionality is critical for applications to detect writeback
error with system calls like fsync(2)/fdatasync(2).

However filemap_fdatawait() is also used by sync(2) or FIFREEZE ioctl,
which don't check error status of individual mappings.

As a result, fsync() may not be able to detect writeback error if events
happen in the following order:

   Application                    System admin
   ----------------------------------------------------------
   write data on page cache
                                  Run sync command
                                  writeback completes with error
                                  filemap_fdatawait() clears error
   fsync returns success
   (but the data is not on disk)

This patch adds filemap_fdatawait_keep_errors() for call sites where
writeback error is not handled so that they don't clear error status.

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

All callers use locks_lock_inode_wait() instead.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>

Users of the locks API commonly call either posix_lock_file_wait() or
flock_lock_file_wait() depending upon the lock type.  Add a new function
locks_lock_inode_wait() which will check and call the correct function for
the type of lock passed in.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>

In order to handle the !CONFIG_TRANSPARENT_HUGEPAGES case, we need to
return VM_FAULT_FALLBACK from the inlined dax_pmd_fault(), which is
defined in linux/mm.h.  Given that we don't want to include <linux/mm.h>
in <linux/fs.h>, the easiest solution is to move the DAX-related
functions to a new header, <linux/dax.h>.  We could also have moved
VM_FAULT_* definitions to a new header, or a different header that isn't
quite such a boil-the-ocean header as <linux/mm.h>, but this felt like
the best option.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull vfs updates from Al Viro:
 "In this one:

   - d_move fixes (Eric Biederman)

   - UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
     handling ought to be fixed)

   - switch of sb_writers to percpu rwsem (Oleg Nesterov)

   - superblock scalability (Josef Bacik and Dave Chinner)

   - swapon(2) race fix (Hugh Dickins)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
  vfs: Test for and handle paths that are unreachable from their mnt_root
  dcache: Reduce the scope of i_lock in d_splice_alias
  dcache: Handle escaped paths in prepend_path
  mm: fix potential data race in SyS_swapon
  inode: don't softlockup when evicting inodes
  inode: rename i_wb_list to i_io_list
  sync: serialise per-superblock sync operations
  inode: convert inode_sb_list_lock to per-sb
  inode: add hlist_fake to avoid the inode hash lock in evict
  writeback: plug writeback at a high level
  change sb_writers to use percpu_rw_semaphore
  shift percpu_counter_destroy() into destroy_super_work()
  percpu-rwsem: kill CONFIG_PERCPU_RWSEM
  percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
  percpu-rwsem: introduce percpu_down_read_trylock()
  document rwsem_release() in sb_wait_write()
  fix the broken lockdep logic in __sb_start_write()
  introduce __sb_writers_{acquired,release}() helpers
  ufs_inode_get{frag,block}(): get rid of 'phys' argument
  ufs_getfrag_block(): tidy up a bit
  ...