vti6: Remove dst_entry caching

Unlike ip6_tunnel, vti6 can lookup multiple different dst entries,
dependent of the configured xfrm states. Therefore it does not make
sense to cache a dst_entry.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 8649143..f5ba4d4 100644 (file)
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -278,7 +278,6 @@ static void vti6_dev_uninit(struct net_device *dev)
                RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
        else
                vti6_tnl_unlink(ip6n, t);
-       ip6_tnl_dst_reset(t);
        dev_put(dev);
 }
 
@@ -356,11 +355,10 @@ vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
  **/
 static int vti6_xmit(struct sk_buff *skb, struct net_device *dev)
 {
-       struct net *net = dev_net(dev);
        struct ip6_tnl *t = netdev_priv(dev);
        struct net_device_stats *stats = &t->dev->stats;
-       struct dst_entry *dst = NULL, *ndst = NULL;
-       struct flowi6 fl6;
+       struct dst_entry *dst = skb_dst(skb);
+       struct flowi fl;
        struct ipv6hdr *ipv6h = ipv6_hdr(skb);
        struct net_device *tdev;
        int err = -1;
@@ -369,21 +367,19 @@ static int vti6_xmit(struct sk_buff *skb, struct net_device *dev)
            !ip6_tnl_xmit_ctl(t) || vti6_addr_conflict(t, ipv6h))
                return err;
 
-       dst = ip6_tnl_dst_check(t);
-       if (!dst) {
-               memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+       memset(&fl, 0, sizeof(fl));
+       skb->mark = be32_to_cpu(t->parms.o_key);
+       xfrm_decode_session(skb, &fl, AF_INET6);
 
-               ndst = ip6_route_output(net, NULL, &fl6);
+       if (!dst)
+               goto tx_err_link_failure;
 
-               if (ndst->error)
-                       goto tx_err_link_failure;
-               ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(&fl6), NULL, 0);
-               if (IS_ERR(ndst)) {
-                       err = PTR_ERR(ndst);
-                       ndst = NULL;
-                       goto tx_err_link_failure;
-               }
-               dst = ndst;
+       dst_hold(dst);
+       dst = xfrm_lookup(t->net, dst, &fl, NULL, 0);
+       if (IS_ERR(dst)) {
+               err = PTR_ERR(dst);
+               dst = NULL;
+               goto tx_err_link_failure;
        }
 
        if (!dst->xfrm || dst->xfrm->props.mode != XFRM_MODE_TUNNEL)
@@ -399,21 +395,19 @@ static int vti6_xmit(struct sk_buff *skb, struct net_device *dev)
        }
 
 
-       skb_dst_drop(skb);
-       skb_dst_set_noref(skb, dst);
+       memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
+       skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
+       skb_dst_set(skb, dst);
+       skb->dev = skb_dst(skb)->dev;
 
        ip6tunnel_xmit(skb, dev);
-       if (ndst) {
-               dev->mtu = dst_mtu(ndst);
-               ip6_tnl_dst_store(t, ndst);
-       }
 
        return 0;
 tx_err_link_failure:
        stats->tx_carrier_errors++;
        dst_link_failure(skb);
 tx_err_dst_release:
-       dst_release(ndst);
+       dst_release(dst);
        return err;
 }