drivers: use req op accessor

The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 52963a2..6fd1601 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -844,7 +844,8 @@
 	if (unlikely(rinfo->dev_info->connected != BLKIF_STATE_CONNECTED))
 		return 1;
 
-	if (unlikely(req->cmd_flags & (REQ_DISCARD | REQ_SECURE)))
+	if (unlikely(req_op(req) == REQ_OP_DISCARD ||
+		     req->cmd_flags & REQ_SECURE))
 		return blkif_queue_discard_req(req, rinfo);
 	else
 		return blkif_queue_rw_req(req, rinfo);
@@ -2054,8 +2055,9 @@
 			/*
 			 * Get the bios in the request so we can re-queue them.
 			 */
-			if (copy[i].request->cmd_flags &
-			    (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) {
+			if (copy[i].request->cmd_flags & REQ_FLUSH ||
+			    req_op(copy[i].request) == REQ_OP_DISCARD ||
+			    copy[i].request->cmd_flags & (REQ_FUA | REQ_SECURE)) {
 				/*
 				 * Flush operations don't contain bios, so
 				 * we need to requeue the whole request