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>

diff --git a/include/net/arp.h b/include/net/arp.h
index 5e669e6..4979af8 100644 (file)
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -38,15 +38,6 @@ static inline struct neighbour *__ipv4_neigh_lookup(struct neigh_table *tbl, str
        return n;
 }
 
-static inline struct neighbour *ipv4_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const __be32 *pkey)
-{
-       struct neighbour *n = __ipv4_neigh_lookup(tbl, dev,
-                                                 *(__force u32 *)pkey);
-       if (n)
-               return n;
-       return neigh_create(tbl, pkey, dev);
-}
-
 extern void    arp_init(void);
 extern int     arp_find(unsigned char *haddr, struct sk_buff *skb);
 extern int     arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);

diff --git a/include/net/dst.h b/include/net/dst.h
index 8147206..29e2557 100644 (file)
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -387,6 +387,11 @@ static inline void dst_confirm(struct dst_entry *dst)
        }
 }
 
+static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+       return dst->ops->neigh_lookup(dst, daddr);
+}
+
 static inline void dst_link_failure(struct sk_buff *skb)
 {
        struct dst_entry *dst = skb_dst(skb);

diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h
index dc07463..9adb998 100644 (file)
--- a/include/net/dst_ops.h
+++ b/include/net/dst_ops.h
@@ -26,6 +26,7 @@ struct dst_ops {
        void                    (*link_failure)(struct sk_buff *);
        void                    (*update_pmtu)(struct dst_entry *dst, u32 mtu);
        int                     (*local_out)(struct sk_buff *skb);
+       struct neighbour *      (*neigh_lookup)(const struct dst_entry *dst, const void *daddr);
 
        struct kmem_cache       *kmem_cachep;
 

diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index b1a5f97..d6ec372 100644 (file)
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -109,11 +109,17 @@ static u32 *fake_cow_metrics(struct dst_entry *dst, unsigned long old)
        return NULL;
 }
 
+static struct neighbour *fake_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+       return NULL;
+}
+
 static struct dst_ops fake_dst_ops = {
        .family =               AF_INET,
        .protocol =             cpu_to_be16(ETH_P_IP),
        .update_pmtu =          fake_update_pmtu,
        .cow_metrics =          fake_cow_metrics,
+       .neigh_lookup =         fake_neigh_lookup,
 };
 
 /*

diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 9bd45fc..43450c1 100644 (file)
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -116,6 +116,7 @@ static void dn_dst_destroy(struct dst_entry *);
 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
 static void dn_dst_link_failure(struct sk_buff *);
 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
+static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr);
 static int dn_route_input(struct sk_buff *);
 static void dn_run_flush(unsigned long dummy);
 
@@ -139,6 +140,7 @@ static struct dst_ops dn_dst_ops = {
        .negative_advice =      dn_dst_negative_advice,
        .link_failure =         dn_dst_link_failure,
        .update_pmtu =          dn_dst_update_pmtu,
+       .neigh_lookup =         dn_dst_neigh_lookup,
 };
 
 static void dn_dst_destroy(struct dst_entry *dst)
@@ -827,6 +829,11 @@ static unsigned int dn_dst_default_mtu(const struct dst_entry *dst)
        return dst->dev->mtu;
 }
 
+static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+       return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
+}
+
 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 {
        struct dn_fib_info *fi = res->fi;

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 1d4cd3b..3313730 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -185,6 +185,8 @@ static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
        return p;
 }
 
+static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr);
+
 static struct dst_ops ipv4_dst_ops = {
        .family =               AF_INET,
        .protocol =             cpu_to_be16(ETH_P_IP),
@@ -199,6 +201,7 @@ static struct dst_ops ipv4_dst_ops = {
        .link_failure =         ipv4_link_failure,
        .update_pmtu =          ip_rt_update_pmtu,
        .local_out =            __ip_local_out,
+       .neigh_lookup =         ipv4_neigh_lookup,
 };
 
 #define ECN_OR_COST(class)     TC_PRIO_##class
@@ -1008,22 +1011,30 @@ static int slow_chain_length(const struct rtable *head)
        return length >> FRACT_BITS;
 }
 
-static int rt_bind_neighbour(struct rtable *rt)
+static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr)
 {
-       static const __be32 inaddr_any = 0;
-       struct net_device *dev = rt->dst.dev;
        struct neigh_table *tbl = &arp_tbl;
-       const __be32 *nexthop;
+       static const __be32 inaddr_any = 0;
+       struct net_device *dev = dst->dev;
+       const __be32 *pkey = daddr;
        struct neighbour *n;
 
 #if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
        if (dev->type == ARPHRD_ATM)
                tbl = clip_tbl_hook;
 #endif
-       nexthop = &rt->rt_gateway;
        if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
-               nexthop = &inaddr_any;
-       n = ipv4_neigh_lookup(tbl, dev, nexthop);
+               pkey = &inaddr_any;
+
+       n = __ipv4_neigh_lookup(tbl, dev, *(__force u32 *)pkey);
+       if (n)
+               return n;
+       return neigh_create(tbl, pkey, dev);
+}
+
+static int rt_bind_neighbour(struct rtable *rt)
+{
+       struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
        if (IS_ERR(n))
                return PTR_ERR(n);
        dst_set_neighbour(&rt->dst, n);
@@ -2734,6 +2745,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
        .default_advmss         =       ipv4_default_advmss,
        .update_pmtu            =       ipv4_rt_blackhole_update_pmtu,
        .cow_metrics            =       ipv4_rt_blackhole_cow_metrics,
+       .neigh_lookup           =       ipv4_neigh_lookup,
 };
 
 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 2998cb5..ddef80f 100644 (file)
--- 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] = {

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 7803eb6..94fdcc7 100644 (file)
--- 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;