[PATCH 0/17] Make O_SYNC handling use standard syncing path (Version 2)

[Jan Kara <jack@suse.cz>]

   Hi,

  first, sorry for a few patches sent before this one - I forgot to give
--compose to git send-email and there was a bug in the third patch.
  This is the second version of my patch set improving O_SYNC implementation.
The changes against previous version are small. Most notably
generic_file_aio_write() now triggers fsync() even when it returns EIOCBQUEUED
so that we behave the same way as generic_file_direct_write() did. I've
added patch renaming generic_file_aio_write_nolock() to device_aio_write()
(since it's used by fs/block_dev.c and drivers/char/raw.c). And finally
I've optimized XFS syncing as Christoph has suggested.
  Any comments welcome and BTW I'd be happy if affected fs maintainers
had a look at those patches so that I can add their ack.
									Honza
---
  Here's some rationale for the patch set:
The patch set unifines O_SYNC handling with standard fsync() path.  After this,
we have just one place forcing a single file to disk so filesystems like ext3 /
ext4 don't have to force a transaction commit in ext?_file_write for O_SYNC
files / IS_SYNC inodes.  The code is also cleaner this way (actually about 150
lines shorter), we don't sync the inode several times as it happened previously
etc.