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/ipv6/route.c b/net/ipv6/route.c
index 2998cb5..ddef80f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -127,6 +127,11 @@ static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 	return p;
 }
 
+static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+	return __neigh_lookup_errno(&nd_tbl, daddr, dst->dev);
+}
+
 static struct dst_ops ip6_dst_ops_template = {
 	.family			=	AF_INET6,
 	.protocol		=	cpu_to_be16(ETH_P_IPV6),
@@ -142,6 +147,7 @@ static struct dst_ops ip6_dst_ops_template = {
 	.link_failure		=	ip6_link_failure,
 	.update_pmtu		=	ip6_rt_update_pmtu,
 	.local_out		=	__ip6_local_out,
+	.neigh_lookup		=	ip6_neigh_lookup,
 };
 
 static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
@@ -168,6 +174,7 @@ static struct dst_ops ip6_dst_blackhole_ops = {
 	.default_advmss		=	ip6_default_advmss,
 	.update_pmtu		=	ip6_rt_blackhole_update_pmtu,
 	.cow_metrics		=	ip6_rt_blackhole_cow_metrics,
+	.neigh_lookup		=	ip6_neigh_lookup,
 };
 
 static const u32 ip6_template_metrics[RTAX_MAX] = {