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 2998cb5be90b..ddef80f568b0 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] = {