Hi all,

The fs/ntfs runtime metadata-corruption paths only record the in-memory
NVolErrors() flag, and the dirty-bit persistence used to race with
ntfs_sync_fs(): a volume could end up with a clean on-disk dirty flag
despite modification or recorded corruption, so chkdsk would not run on
the next mount.  This series fixes that.

   1/6 makes the volume flag read-modify-write atomic under the
      $Volume mrec_lock;
   2/6 marks the volume dirty unconditionally on metadata changes,
      dropping the racy caller-side checks in file.c and namei.c;
   3/6 derives the on-disk dirty bit from the recorded error state at
      the persistence points (sync_fs, remount-ro, put_super) and never
      writes a hibernated volume;
   4/6 persists the dirty state after the final put_super() commits so
      late errors cannot unmount clean;
   5/6 stops ntfs_sync_fs() from clearing VOLUME_IS_DIRTY: the clearing
      moves to the quiescent transitions, a recorded error state is
      still persisted at sync time, and sync now reports writeback and
      flush errors instead of discarding them;
   6/6 checks the dirty-state commit on remount and unmount.

Changes in this revision, from the review:

  - 5/6: with the clearing gone from the sync path, a recorded error
    state is persisted without ever clearing the bit, and
    sync_blockdev() and blkdev_issue_flush() are both called with the
    first error returned.

  - The IOCB_NOWAIT behavior and the per-operation $Volume mrec_lock
    acquisition are outside the scope of this series.  The series keeps
    the unconditional ntfs_set_volume_flags() call to preserve the
    ordering that marks the volume dirty before the metadata
    modification; a RWF_NOWAIT write still blocks in the marking when
    the volume looks clean, as it already did on the base.  The
    non-blocking and contended-lock handling (mutex_trylock, GFP_NOWAIT)
    will be addressed in a separate follow-up patch.

Hongling Zeng (4):
  ntfs: fix volume flag update races
  ntfs: set the volume dirty bit unconditionally on metadata changes
  ntfs: sync the volume dirty bit with the recorded error state
  ntfs: persist the dirty state after the final put_super() commits

 fs/ntfs/file.c   |  20 ++---
 fs/ntfs/namei.c  |  24 ++----
 fs/ntfs/ntfs.h   |   1 -
 fs/ntfs/super.c  | 191 ++++++++++++++++++++++++++++++++++++-----------
 fs/ntfs/volume.h |   4 +
 5 files changed, 171 insertions(+), 69 deletions(-)

-- 
2.25.1