Commit f83c7790 authored by David S. Miller's avatar David S. Miller
Browse files

ipv6: Create fast inline ipv6 neigh lookup just like ipv4. 



Also, create and use an rt6_bind_neighbour() in net/ipv6/route.c to
consolidate some common logic.

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2c2aba6c

include/net/ndisc.h

+27 −0
Original line number Diff line number Diff line
@@ -89,6 +89,33 @@ static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, _ 
		(p32[3] * hash_rnd[3]));

}



static inline struct neighbour *__ipv6_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const void *pkey)

{

	struct neigh_hash_table *nht;

	const u32 *p32 = pkey;

	struct neighbour *n;

	u32 hash_val;



	rcu_read_lock_bh();

	nht = rcu_dereference_bh(tbl->nht);

	hash_val = ndisc_hashfn(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);

	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);

	     n != NULL;

	     n = rcu_dereference_bh(n->next)) {

		u32 *n32 = (u32 *) n->primary_key;

		if (n->dev == dev &&

		    ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |

		     (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) {

			if (!atomic_inc_not_zero(&n->refcnt))

				n = NULL;

			break;

		}

	}

	rcu_read_unlock_bh();



	return n;

}



extern int			ndisc_init(void);



extern void			ndisc_cleanup(void);

net/ipv6/route.c

+22 −19
Original line number Diff line number Diff line
@@ -123,7 +123,20 @@ static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old) 


static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, const void *daddr)

{

	return __neigh_lookup_errno(&nd_tbl, daddr, dst->dev);

	struct neighbour *n = __ipv6_neigh_lookup(&nd_tbl, dst->dev, daddr);

	if (n)

		return n;

	return neigh_create(&nd_tbl, daddr, dst->dev);

}



static int rt6_bind_neighbour(struct rt6_info *rt)

{

	struct neighbour *n = ip6_neigh_lookup(&rt->dst, &rt->rt6i_gateway);

	if (IS_ERR(n))

		return PTR_ERR(n);

	dst_set_neighbour(&rt->dst, n);



	return 0;

}



static struct dst_ops ip6_dst_ops_template = {
@@ -714,7 +727,6 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort, 
	rt = ip6_rt_copy(ort, daddr);



	if (rt) {

		struct neighbour *neigh;

		int attempts = !in_softirq();



		if (!(rt->rt6i_flags & RTF_GATEWAY)) {
@@ -734,9 +746,7 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort, 
#endif



	retry:

		neigh = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway,

					     rt->rt6i_dev);

		if (IS_ERR(neigh)) {

		if (rt6_bind_neighbour(rt)) {

			struct net *net = dev_net(rt->rt6i_dev);

			int saved_rt_min_interval =

				net->ipv6.sysctl.ip6_rt_gc_min_interval;
@@ -762,8 +772,6 @@ static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort, 
			dst_free(&rt->dst);

			return NULL;

		}

		dst_set_neighbour(&rt->dst, neigh);



	}



	return rt;
@@ -1078,7 +1086,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev, 
	if (neigh)

		neigh_hold(neigh);

	else {

		neigh = __neigh_lookup_errno(&nd_tbl, &fl6->daddr, dev);

		neigh = ip6_neigh_lookup(&rt->dst, &fl6->daddr);

		if (IS_ERR(neigh)) {

			dst_free(&rt->dst);

			return ERR_CAST(neigh);
@@ -1389,13 +1397,10 @@ int ip6_route_add(struct fib6_config *cfg) 
		rt->rt6i_prefsrc.plen = 0;



	if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {

		struct neighbour *n = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);

		if (IS_ERR(n)) {

			err = PTR_ERR(n);

		err = rt6_bind_neighbour(rt);

		if (err)

			goto out;

	}

		dst_set_neighbour(&rt->dst, n);

	}



	rt->rt6i_flags = cfg->fc_flags;
@@ -2057,7 +2062,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 
	struct net *net = dev_net(idev->dev);

	struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,

					    net->loopback_dev, 0);

	struct neighbour *neigh;

	int err;



	if (!rt) {

		if (net_ratelimit())
@@ -2079,13 +2084,11 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 
		rt->rt6i_flags |= RTF_ANYCAST;

	else

		rt->rt6i_flags |= RTF_LOCAL;

	neigh = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, rt->rt6i_dev);

	if (IS_ERR(neigh)) {

	err = rt6_bind_neighbour(rt);

	if (err) {

		dst_free(&rt->dst);



		return ERR_CAST(neigh);

		return ERR_PTR(err);

	}

	dst_set_neighbour(&rt->dst, neigh);



	rt->rt6i_dst.addr = *addr;

	rt->rt6i_dst.plen = 128;