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>

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>
David S. Miller · Eric Lee
1 parent 69cce1d140
Showing 8 changed files with 52 additions and 16 deletions Side-by-side Diff
include/net/arp.h
include/net/dst.h
include/net/dst_ops.h
net/bridge/br_netfilter.c
net/decnet/dn_route.c
net/ipv4/route.c
net/ipv6/route.c
net/xfrm/xfrm_policy.c
@@ -38,15 +38,6 @@
 	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);
@@ -387,6 +387,11 @@
 	}
 }
  
+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);
@@ -26,6 +26,7 @@
 	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;
  
@@ -109,11 +109,17 @@
 	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,
 };
  
 /*
@@ -116,6 +116,7 @@
 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 @@
 	.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)
@@ -825,6 +827,11 @@
 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)
@@ -185,6 +185,8 @@
 	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 @@
 	.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 @@
 	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 @@
 	.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)
@@ -127,6 +127,11 @@
 	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 @@
 	.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 @@
 	.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] = {
@@ -2385,6 +2385,11 @@
 	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 @@
 			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;
...	...	@@ -38,15 +38,6 @@
38	38	return n;
39	39	}
40	40
41		-static inline struct neighbour ipv4_neigh_lookup(struct neigh_table tbl, struct net_device dev, const __be32 pkey)
42		-{
43		- struct neighbour *n = __ipv4_neigh_lookup(tbl, dev,
44		- (__force u32 )pkey);
45		- if (n)
46		- return n;
47		- return neigh_create(tbl, pkey, dev);
48		-}
49		-
50	41	extern void arp_init(void);
51	42	extern int arp_find(unsigned char haddr, struct sk_buff skb);
52	43	extern int arp_ioctl(struct net net, unsigned int cmd, void __user arg);
...	...	@@ -387,6 +387,11 @@
387	387	}
388	388	}
389	389
	390	+static inline struct neighbour dst_neigh_lookup(const struct dst_entry dst, const void *daddr)
	391	+{
	392	+ return dst->ops->neigh_lookup(dst, daddr);
	393	+}
	394	+
390	395	static inline void dst_link_failure(struct sk_buff *skb)
391	396	{
392	397	struct dst_entry *dst = skb_dst(skb);
...	...	@@ -26,6 +26,7 @@
26	26	void (link_failure)(struct sk_buff );
27	27	void (update_pmtu)(struct dst_entry dst, u32 mtu);
28	28	int (local_out)(struct sk_buff skb);
	29	+ struct neighbour * (neigh_lookup)(const struct dst_entry dst, const void *daddr);
29	30
30	31	struct kmem_cache *kmem_cachep;
31	32
...	...	@@ -109,11 +109,17 @@
109	109	return NULL;
110	110	}
111	111
	112	+static struct neighbour fake_neigh_lookup(const struct dst_entry dst, const void *daddr)
	113	+{
	114	+ return NULL;
	115	+}
	116	+
112	117	static struct dst_ops fake_dst_ops = {
113	118	.family = AF_INET,
114	119	.protocol = cpu_to_be16(ETH_P_IP),
115	120	.update_pmtu = fake_update_pmtu,
116	121	.cow_metrics = fake_cow_metrics,
	122	+ .neigh_lookup = fake_neigh_lookup,
117	123	};
118	124
119	125	/*
...	...	@@ -116,6 +116,7 @@
116	116	static struct dst_entry dn_dst_negative_advice(struct dst_entry );
117	117	static void dn_dst_link_failure(struct sk_buff *);
118	118	static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
	119	+static struct neighbour dn_dst_neigh_lookup(const struct dst_entry dst, const void *daddr);
119	120	static int dn_route_input(struct sk_buff *);
120	121	static void dn_run_flush(unsigned long dummy);
121	122
...	...	@@ -139,6 +140,7 @@
139	140	.negative_advice = dn_dst_negative_advice,
140	141	.link_failure = dn_dst_link_failure,
141	142	.update_pmtu = dn_dst_update_pmtu,
	143	+ .neigh_lookup = dn_dst_neigh_lookup,
142	144	};
143	145
144	146	static void dn_dst_destroy(struct dst_entry *dst)
...	...	@@ -825,6 +827,11 @@
825	827	static unsigned int dn_dst_default_mtu(const struct dst_entry *dst)
826	828	{
827	829	return dst->dev->mtu;
	830	+}
	831	+
	832	+static struct neighbour dn_dst_neigh_lookup(const struct dst_entry dst, const void *daddr)
	833	+{
	834	+ return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
828	835	}
829	836
830	837	static int dn_rt_set_next_hop(struct dn_route rt, struct dn_fib_res res)
...	...	@@ -185,6 +185,8 @@
185	185	return p;
186	186	}
187	187
	188	+static struct neighbour ipv4_neigh_lookup(const struct dst_entry dst, const void *daddr);
	189	+
188	190	static struct dst_ops ipv4_dst_ops = {
189	191	.family = AF_INET,
190	192	.protocol = cpu_to_be16(ETH_P_IP),
...	...	@@ -199,6 +201,7 @@
199	201	.link_failure = ipv4_link_failure,
200	202	.update_pmtu = ip_rt_update_pmtu,
201	203	.local_out = __ip_local_out,
	204	+ .neigh_lookup = ipv4_neigh_lookup,
202	205	};
203	206
204	207	#define ECN_OR_COST(class) TC_PRIO_##class
205	208
206	209
207	210
208	211
...	...	@@ -1008,22 +1011,30 @@
1008	1011	return length >> FRACT_BITS;
1009	1012	}
1010	1013
1011		-static int rt_bind_neighbour(struct rtable *rt)
	1014	+static struct neighbour ipv4_neigh_lookup(const struct dst_entry dst, const void *daddr)
1012	1015	{
1013		- static const __be32 inaddr_any = 0;
1014		- struct net_device *dev = rt->dst.dev;
1015	1016	struct neigh_table *tbl = &arp_tbl;
1016		- const __be32 *nexthop;
	1017	+ static const __be32 inaddr_any = 0;
	1018	+ struct net_device *dev = dst->dev;
	1019	+ const __be32 *pkey = daddr;
1017	1020	struct neighbour *n;
1018	1021
1019	1022	#if defined(CONFIG_ATM_CLIP) \|\| defined(CONFIG_ATM_CLIP_MODULE)
1020	1023	if (dev->type == ARPHRD_ATM)
1021	1024	tbl = clip_tbl_hook;
1022	1025	#endif
1023		- nexthop = &rt->rt_gateway;
1024	1026	if (dev->flags & (IFF_LOOPBACK \| IFF_POINTOPOINT))
1025		- nexthop = &inaddr_any;
1026		- n = ipv4_neigh_lookup(tbl, dev, nexthop);
	1027	+ pkey = &inaddr_any;
	1028	+
	1029	+ n = __ipv4_neigh_lookup(tbl, dev, (__force u32 )pkey);
	1030	+ if (n)
	1031	+ return n;
	1032	+ return neigh_create(tbl, pkey, dev);
	1033	+}
	1034	+
	1035	+static int rt_bind_neighbour(struct rtable *rt)
	1036	+{
	1037	+ struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
1027	1038	if (IS_ERR(n))
1028	1039	return PTR_ERR(n);
1029	1040	dst_set_neighbour(&rt->dst, n);
...	...	@@ -2734,6 +2745,7 @@
2734	2745	.default_advmss = ipv4_default_advmss,
2735	2746	.update_pmtu = ipv4_rt_blackhole_update_pmtu,
2736	2747	.cow_metrics = ipv4_rt_blackhole_cow_metrics,
	2748	+ .neigh_lookup = ipv4_neigh_lookup,
2737	2749	};
2738	2750
2739	2751	struct dst_entry ipv4_blackhole_route(struct net net, struct dst_entry *dst_orig)
...	...	@@ -127,6 +127,11 @@
127	127	return p;
128	128	}
129	129
	130	+static struct neighbour ip6_neigh_lookup(const struct dst_entry dst, const void *daddr)
	131	+{
	132	+ return __neigh_lookup_errno(&nd_tbl, daddr, dst->dev);
	133	+}
	134	+
130	135	static struct dst_ops ip6_dst_ops_template = {
131	136	.family = AF_INET6,
132	137	.protocol = cpu_to_be16(ETH_P_IPV6),
...	...	@@ -142,6 +147,7 @@
142	147	.link_failure = ip6_link_failure,
143	148	.update_pmtu = ip6_rt_update_pmtu,
144	149	.local_out = __ip6_local_out,
	150	+ .neigh_lookup = ip6_neigh_lookup,
145	151	};
146	152
147	153	static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
...	...	@@ -168,6 +174,7 @@
168	174	.default_advmss = ip6_default_advmss,
169	175	.update_pmtu = ip6_rt_blackhole_update_pmtu,
170	176	.cow_metrics = ip6_rt_blackhole_cow_metrics,
	177	+ .neigh_lookup = ip6_neigh_lookup,
171	178	};
172	179
173	180	static const u32 ip6_template_metrics[RTAX_MAX] = {
...	...	@@ -2385,6 +2385,11 @@
2385	2385	return dst_mtu(dst->path);
2386	2386	}
2387	2387
	2388	+static struct neighbour xfrm_neigh_lookup(const struct dst_entry dst, const void *daddr)
	2389	+{
	2390	+ return dst_neigh_lookup(dst->path, daddr);
	2391	+}
	2392	+
2388	2393	int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2389	2394	{
2390	2395	struct net *net;
...	...	@@ -2410,6 +2415,8 @@
2410	2415	dst_ops->negative_advice = xfrm_negative_advice;
2411	2416	if (likely(dst_ops->link_failure == NULL))
2412	2417	dst_ops->link_failure = xfrm_link_failure;
	2418	+ if (likely(dst_ops->neigh_lookup == NULL))
	2419	+ dst_ops->neigh_lookup = xfrm_neigh_lookup;
2413	2420	if (likely(afinfo->garbage_collect == NULL))
2414	2421	afinfo->garbage_collect = __xfrm_garbage_collect;
2415	2422	xfrm_policy_afinfo[afinfo->family] = afinfo;