[XFS] A bug was found in xfs_bmap_add_extent_unwritten_real(). In a

particular case, the delta param which is supposed to describe the region
where extents have changed was not updated appropriately.

SGI-PV: 984030

SGI-Modid: xfs-linux-melb:xfs-kern:31663a
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Olaf Weber <olaf@sgi.com>

fs/xfs/xfs_bmap.c

@@ -1740,9 +1740,9 @@ xfs_bmap_add_extent_unwritten_real(
 				r[1].br_state)))
 				goto done;
 			/* new left extent - oldext */
-			PREV.br_blockcount =
-				new->br_startoff - PREV.br_startoff;
 			cur->bc_rec.b = PREV;
+			cur->bc_rec.b.br_blockcount =
+				new->br_startoff - PREV.br_startoff;
 			if ((error = xfs_bmbt_insert(cur, &i)))
 				goto done;
 			XFS_WANT_CORRUPTED_GOTO(i == 1, done);