vxlan: move IPv6 outpute route calculation to a function

Will be used also for ndo_fill_metadata_dst.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

@@ -1848,6 +1848,34 @@ static int vxlan_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *sk
 				   !(vxflags & VXLAN_F_UDP_CSUM));
 }
 
+#if IS_ENABLED(CONFIG_IPV6)
+static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
+					  struct sk_buff *skb, int oif,
+					  const struct in6_addr *daddr,
+					  struct in6_addr *saddr)
+{
+	struct dst_entry *ndst;
+	struct flowi6 fl6;
+	int err;
+
+	memset(&fl6, 0, sizeof(fl6));
+	fl6.flowi6_oif = oif;
+	fl6.daddr = *daddr;
+	fl6.saddr = vxlan->cfg.saddr.sin6.sin6_addr;
+	fl6.flowi6_mark = skb->mark;
+	fl6.flowi6_proto = IPPROTO_UDP;
+
+	err = ipv6_stub->ipv6_dst_lookup(vxlan->net,
+					 vxlan->vn6_sock->sock->sk,
+					 &ndst, &fl6);
+	if (err < 0)
+		return ERR_PTR(err);
+
+	*saddr = fl6.saddr;
+	return ndst;
+}
+#endif
+
 /* Bypass encapsulation if the destination is local */
 static void vxlan_encap_bypass(struct sk_buff *skb, struct vxlan_dev *src_vxlan,
 			       struct vxlan_dev *dst_vxlan)
@@ -2035,21 +2063,17 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 #if IS_ENABLED(CONFIG_IPV6)
 	} else {
 		struct dst_entry *ndst;
-		struct flowi6 fl6;
+		struct in6_addr saddr;
 		u32 rt6i_flags;
 
 		if (!vxlan->vn6_sock)
 			goto drop;
 		sk = vxlan->vn6_sock->sock->sk;
 
-		memset(&fl6, 0, sizeof(fl6));
-		fl6.flowi6_oif = rdst ? rdst->remote_ifindex : 0;
-		fl6.daddr = dst->sin6.sin6_addr;
-		fl6.saddr = vxlan->cfg.saddr.sin6.sin6_addr;
-		fl6.flowi6_mark = skb->mark;
-		fl6.flowi6_proto = IPPROTO_UDP;
-
-		if (ipv6_stub->ipv6_dst_lookup(vxlan->net, sk, &ndst, &fl6)) {
+		ndst = vxlan6_get_route(vxlan, skb,
+					rdst ? rdst->remote_ifindex : 0,
+					&dst->sin6.sin6_addr, &saddr);
+		if (IS_ERR(ndst)) {
 			netdev_dbg(dev, "no route to %pI6\n",
 				   &dst->sin6.sin6_addr);
 			dev->stats.tx_carrier_errors++;
@@ -2081,7 +2105,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 		}
 
 		ttl = ttl ? : ip6_dst_hoplimit(ndst);
-		err = vxlan6_xmit_skb(ndst, sk, skb, dev, &fl6.saddr, &fl6.daddr,
+		err = vxlan6_xmit_skb(ndst, sk, skb, dev, &saddr, &dst->sin6.sin6_addr,
 				      0, ttl, src_port, dst_port, htonl(vni << 8), md,
 				      !net_eq(vxlan->net, dev_net(vxlan->dev)),
 				      flags);