net: Add ->neigh_lookup() operation to dst_ops

In the future dst entries will be neigh-less.  In that environment we
need to have an easy transition point for current users of
dst->neighbour outside of the packet output fast path.

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

1 files changed, 7 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 7803eb6af414..94fdcc7f1030 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2385,6 +2385,11 @@ static unsigned int xfrm_default_mtu(const struct dst_entry *dst)
         return dst_mtu(dst->path);
 }
 
+static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+        return dst_neigh_lookup(dst->path, daddr);
+}
+
 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 {
         struct net *net;
@@ -2410,6 +2415,8 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
                         dst_ops->negative_advice = xfrm_negative_advice;
                 if (likely(dst_ops->link_failure == NULL))
                         dst_ops->link_failure = xfrm_link_failure;
+                if (likely(dst_ops->neigh_lookup == NULL))
+                        dst_ops->neigh_lookup = xfrm_neigh_lookup;
                 if (likely(afinfo->garbage_collect == NULL))
                         afinfo->garbage_collect = __xfrm_garbage_collect;
                 xfrm_policy_afinfo[afinfo->family] = afinfo;