openvswitch: Introduce ovs_tunnel_route_lookup

Introduce ovs_tunnel_route_lookup to consolidate route lookup
shared by vxlan, gre, and geneve ports.

Signed-off-by: Fan Du <fan.du@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/vport-geneve.c b/net/openvswitch/vport-geneve.c
index 2daf144..88a010c 100644
--- a/net/openvswitch/vport-geneve.c
+++ b/net/openvswitch/vport-geneve.c
@@ -170,7 +170,7 @@
 
 static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
-	struct ovs_key_ipv4_tunnel *tun_key;
+	const struct ovs_key_ipv4_tunnel *tun_key;
 	struct ovs_tunnel_info *tun_info;
 	struct net *net = ovs_dp_get_net(vport->dp);
 	struct geneve_port *geneve_port = geneve_vport(vport);
@@ -189,16 +189,7 @@
 	}
 
 	tun_key = &tun_info->tunnel;
-
-	/* Route lookup */
-	memset(&fl, 0, sizeof(fl));
-	fl.daddr = tun_key->ipv4_dst;
-	fl.saddr = tun_key->ipv4_src;
-	fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-	fl.flowi4_mark = skb->mark;
-	fl.flowi4_proto = IPPROTO_UDP;
-
-	rt = ip_route_output_key(net, &fl);
+	rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);
 		goto error;
diff --git a/net/openvswitch/vport-gre.c b/net/openvswitch/vport-gre.c
index e9aedb7..f17ac96 100644
--- a/net/openvswitch/vport-gre.c
+++ b/net/openvswitch/vport-gre.c
@@ -134,7 +134,7 @@
 static int gre_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
 	struct net *net = ovs_dp_get_net(vport->dp);
-	struct ovs_key_ipv4_tunnel *tun_key;
+	const struct ovs_key_ipv4_tunnel *tun_key;
 	struct flowi4 fl;
 	struct rtable *rt;
 	int min_headroom;
@@ -148,15 +148,7 @@
 	}
 
 	tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
-	/* Route lookup */
-	memset(&fl, 0, sizeof(fl));
-	fl.daddr = tun_key->ipv4_dst;
-	fl.saddr = tun_key->ipv4_src;
-	fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-	fl.flowi4_mark = skb->mark;
-	fl.flowi4_proto = IPPROTO_GRE;
-
-	rt = ip_route_output_key(net, &fl);
+	rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_GRE);
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);
 		goto err_free_skb;
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
index d7c46b3..1435a05 100644
--- a/net/openvswitch/vport-vxlan.c
+++ b/net/openvswitch/vport-vxlan.c
@@ -145,7 +145,7 @@
 	struct net *net = ovs_dp_get_net(vport->dp);
 	struct vxlan_port *vxlan_port = vxlan_vport(vport);
 	__be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
-	struct ovs_key_ipv4_tunnel *tun_key;
+	const struct ovs_key_ipv4_tunnel *tun_key;
 	struct rtable *rt;
 	struct flowi4 fl;
 	__be16 src_port;
@@ -158,15 +158,7 @@
 	}
 
 	tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
-	/* Route lookup */
-	memset(&fl, 0, sizeof(fl));
-	fl.daddr = tun_key->ipv4_dst;
-	fl.saddr = tun_key->ipv4_src;
-	fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-	fl.flowi4_mark = skb->mark;
-	fl.flowi4_proto = IPPROTO_UDP;
-
-	rt = ip_route_output_key(net, &fl);
+	rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);
 		goto error;
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index 464739a..ec2954f 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -595,14 +595,7 @@
 	 * The process may need to be changed if the corresponding process
 	 * in vports ops changed.
 	 */
-	memset(&fl, 0, sizeof(fl));
-	fl.daddr = tun_key->ipv4_dst;
-	fl.saddr = tun_key->ipv4_src;
-	fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-	fl.flowi4_mark = skb_mark;
-	fl.flowi4_proto = ipproto;
-
-	rt = ip_route_output_key(net, &fl);
+	rt = ovs_tunnel_route_lookup(net, tun_key, skb_mark, &fl, ipproto);
 	if (IS_ERR(rt))
 		return PTR_ERR(rt);
 
diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h
index 99c8e71..f8ae295 100644
--- a/net/openvswitch/vport.h
+++ b/net/openvswitch/vport.h
@@ -236,4 +236,22 @@
 int ovs_vport_ops_register(struct vport_ops *ops);
 void ovs_vport_ops_unregister(struct vport_ops *ops);
 
+static inline struct rtable *ovs_tunnel_route_lookup(struct net *net,
+						     const struct ovs_key_ipv4_tunnel *key,
+						     u32 mark,
+						     struct flowi4 *fl,
+						     u8 protocol)
+{
+	struct rtable *rt;
+
+	memset(fl, 0, sizeof(*fl));
+	fl->daddr = key->ipv4_dst;
+	fl->saddr = key->ipv4_src;
+	fl->flowi4_tos = RT_TOS(key->ipv4_tos);
+	fl->flowi4_mark = mark;
+	fl->flowi4_proto = protocol;
+
+	rt = ip_route_output_key(net, fl);
+	return rt;
+}
 #endif /* vport.h */