ipv4: Create and use route lookup helpers.

The idea here is this minimizes the number of places one has to edit
in order to make changes to how flows are defined and used.

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/infiniband/hw/cxgb4/cm.c

@@ -315,23 +315,10 @@ static struct rtable *find_route(struct c4iw_dev *dev, __be32 local_ip,
 				 __be16 peer_port, u8 tos)
 {
 	struct rtable *rt;
-	struct flowi fl = {
-		.oif = 0,
-		.nl_u = {
-			 .ip4_u = {
-				   .daddr = peer_ip,
-				   .saddr = local_ip,
-				   .tos = tos}
-			 },
-		.proto = IPPROTO_TCP,
-		.uli_u = {
-			  .ports = {
-				    .sport = local_port,
-				    .dport = peer_port}
-			  }
-	};
 
-	rt = ip_route_output_flow(&init_net, &fl, NULL);
+	rt = ip_route_output_ports(&init_net, NULL, peer_ip, local_ip,
+				   peer_port, local_port, IPPROTO_TCP,
+				   tos, 0);
 	if (IS_ERR(rt))
 		return NULL;
 	return rt;