afs_fsync

[Christoph Hellwig]

Dave,

I've been looking at afs_fsync a bit lately and don't quite
understanding what's going on there.  As of 2.6.32 we always
write out all data before calling into ->fsync.  From my very
unscientific exploration into afs_fsync it's doing exactly that
data writeout again, just in a rather complicated way, and
then marks the inode as having dirty pages again, which is not
very helpful inside ->fsync.  Any chance you could explain
what's really going on there?