xfs: xfs_iflush() is no longer necessary

Now we have a cached buffer on inode log items, we don't need
to do buffer lookups when flushing inodes anymore - all we need
to do is lock the buffer and we are ready to go.

This largely gets rid of the need for xfs_iflush(), which is
essentially just a mechanism to look up the buffer and flush the
inode to it. Instead, we can just call xfs_iflush_cluster() with a
few modifications to ensure it also flushes the inode we already
hold locked.

This allows the AIL inode item pushing to be almost entirely
non-blocking in XFS - we won't block unless memory allocation
for the cluster inode lookup blocks or the block device queues are
full.

Writeback during inode reclaim becomes a little more complex because
we now have to lock the buffer ourselves, but otherwise this change
is largely a functional no-op that removes a whole lot of code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 1534386b430c..c482e7306fe0 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -426,7 +426,7 @@ int		xfs_log_force_inode(struct xfs_inode *ip);
 void		xfs_iunpin_wait(xfs_inode_t *);
 #define xfs_ipincount(ip)	((unsigned int) atomic_read(&ip->i_pincount))
 
-int		xfs_iflush(struct xfs_inode *, struct xfs_buf **);
+int		xfs_iflush_cluster(struct xfs_inode *, struct xfs_buf *);
 void		xfs_lock_two_inodes(struct xfs_inode *ip0, uint ip0_mode,
 				struct xfs_inode *ip1, uint ip1_mode);