ocfs2: use the OCFS2_XATTR_ROOT_SIZE macro in ocfs2_reflink_xattr_header()

Use the OCFS2_XATTR_ROOT_SIZE macro improves the readability of the
code.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Chen <[email protected]>
Reviewed-by: Jun Piao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Joseph Qi <[email protected]>
Cc: Changwei Ge <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Author: alex chen

fs/ocfs2/xattr.c

@@ -6415,7 +6415,7 @@ static int ocfs2_reflink_xattr_header(handle_t *handle,
 		 * and then insert the extents one by one.
 		 */
 		if (xv->xr_list.l_tree_depth) {
-			memcpy(new_xv, &def_xv, sizeof(def_xv));
+			memcpy(new_xv, &def_xv, OCFS2_XATTR_ROOT_SIZE);
 			vb->vb_xv = new_xv;
 			vb->vb_bh = value_bh;
 			ocfs2_init_xattr_value_extent_tree(&data_et,