[PATCH 5/7] xfs: honor the O_SYNC flag for aysnchronous direct I/O requests

[Jeff Moyer]

Jeff Moyer <jmoyer at redhat.com> writes:

> Jeff Moyer <jmoyer at redhat.com> writes:
>
>> Hi, Dave,
>>
>> Thanks for the review!
>>
>>> or better still, factor xfs_file_fsync() so that it calls a helper
>>> that doesn't wait for data IO completion, and call that helper here
>>> too. The semantics of fsync/fdatasync are too complex to have to
>>> implement and maintain in multiple locations....
>>
>> I definitely agree with consolidating things.  However, there are four
>> blocking calls in xfs_file_fsync (filemap_write_and_wait_range,
>> xfs_blkdev_issue_flush, _xfs_log_force_lsn, and another call to
>> xfs_blkdev_issue_flush).  How would you propose to make that
>> non-blocking given that those steps have to happen in sequence?
>
> OK, so re-reading your mail, I think you meant to just factor out
> everything except the filemap_write_and_wait_range.  Here are a couple
> of patches which do that.  Also, since we're not worried about blocking
> in the endio processing, just making things synchronous makes the code a
> lot simpler.  Let me know what you think of the attached two patches
> (which I've already run through xfstests).

Dave, ping?  Did you have a chance to take a look at these patches?

Cheers,
Jeff