diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 53c81de6f88697b6948f894c918d3f3d3d662bad..a1ee2659d2bc3c8a4659343216f5c161a0a8b413 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -707,7 +707,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 	 * the hypercall to unmap the grants - that is all done in
 	 * xen_blkbk_unmap.
 	 */
-	if (operation == REQ_DISCARD && xen_blkbk_map(req, pending_req, seg))
+	if (operation != REQ_DISCARD && xen_blkbk_map(req, pending_req, seg))
 		goto fail_flush;
 
 	/*