1 files changed, 31 insertions, 3 deletions

diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 73a5fa457e16..aa5a04b844d6 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -397,7 +397,6 @@ shutdown_abort:
 	return XFS_ERROR(EIO);
 }
 
-
 /*
  * Release the buffer bp which was previously acquired with one of the
  * xfs_trans_... buffer allocation routines if the buffer has not
@@ -603,8 +602,14 @@ xfs_trans_log_buf(xfs_trans_t	*tp,
 
 	tp->t_flags |= XFS_TRANS_DIRTY;
 	bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
-	bip->bli_flags |= XFS_BLI_LOGGED;
-	xfs_buf_item_log(bip, first, last);
+
+	/*
+	 * If we have an ordered buffer we are not logging any dirty range but
+	 * it still needs to be marked dirty and that it has been logged.
+	 */
+	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
+	if (!(bip->bli_flags & XFS_BLI_ORDERED))
+		xfs_buf_item_log(bip, first, last);
 }
 
 
@@ -757,6 +762,29 @@ xfs_trans_inode_alloc_buf(
 }
 
 /*
+ * Mark the buffer as ordered for this transaction. This means
+ * that the contents of the buffer are not recorded in the transaction
+ * but it is tracked in the AIL as though it was. This allows us
+ * to record logical changes in transactions rather than the physical
+ * changes we make to the buffer without changing writeback ordering
+ * constraints of metadata buffers.
+ */
+void
+xfs_trans_ordered_buf(
+	struct xfs_trans	*tp,
+	struct xfs_buf		*bp)
+{
+	struct xfs_buf_log_item	*bip = bp->b_fspriv;
+
+	ASSERT(bp->b_transp == tp);
+	ASSERT(bip != NULL);
+	ASSERT(atomic_read(&bip->bli_refcount) > 0);
+
+	bip->bli_flags |= XFS_BLI_ORDERED;
+	trace_xfs_buf_item_ordered(bip);
+}
+
+/*
  * Set the type of the buffer for log recovery so that it can correctly identify
  * and hence attach the correct buffer ops to the buffer after replay.
  */