[PATCH 0/4] Cleanups in extent_io callbacks

[David Sterba <dsterba@suse.com>]

Some of the checks for extent_io callbacks can be safely dropped as they're
always defined, plus some dummy callback additions so more checks can be
dropped. There's more potential for the same cleanup in other callbacks but
this would need more evaluation wheather dummy callbacks vs existence checks
are really worth it.

David Sterba (4):
      btrfs: let writepage_end_io_hook return void
      btrfs: document existence of extent_io ops callbacks
      btrfs: drop checks for mandatory extent_io_ops callbacks
      btrfs: add dummy callback for readpage_io_failed and drop checks

 fs/btrfs/disk-io.c   |  7 +++++--
 fs/btrfs/extent_io.c | 18 +++++++-----------
 fs/btrfs/extent_io.h | 25 +++++++++++++++++--------
 fs/btrfs/inode.c     | 20 ++++++++++++++------
 4 files changed, 43 insertions(+), 27 deletions(-)