net: Abstract dst->neighbour accesses behind helpers.

dst_{get,set}_neighbour()

Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -656,7 +656,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
 	 * layer address of our nexhop router
 	 */
 
-	if (rt->dst.neighbour == NULL)
+	if (dst_get_neighbour(&rt->dst) == NULL)
 		ifa->flags &= ~IFA_F_OPTIMISTIC;
 
 	ifa->idev = idev;

net/ipv6/ip6_fib.c

@@ -1455,7 +1455,7 @@ static int fib6_age(struct rt6_info *rt, void *arg)
 			RT6_TRACE("aging clone %p\n", rt);
 			return -1;
 		} else if ((rt->rt6i_flags & RTF_GATEWAY) &&
-			   (!(rt->dst.neighbour->flags & NTF_ROUTER))) {
+			   (!(dst_get_neighbour(&rt->dst)->flags & NTF_ROUTER))) {
 			RT6_TRACE("purging route %p via non-router but gateway\n",
 				  rt);
 			return -1;

net/ipv6/ip6_output.c

@@ -135,7 +135,7 @@ static int ip6_finish_output2(struct sk_buff *skb)
 				skb->len);
 	}
 
-	neigh = dst->neighbour;
+	neigh = dst_get_neighbour(dst);
 	if (neigh)
 		return neigh_output(neigh, skb);
 
@@ -385,6 +385,7 @@ int ip6_forward(struct sk_buff *skb)
 	struct ipv6hdr *hdr = ipv6_hdr(skb);
 	struct inet6_skb_parm *opt = IP6CB(skb);
 	struct net *net = dev_net(dst->dev);
+	struct neighbour *n;
 	u32 mtu;
 
 	if (net->ipv6.devconf_all->forwarding == 0)
@@ -459,11 +460,10 @@ int ip6_forward(struct sk_buff *skb)
 	   send redirects to source routed frames.
 	   We don't send redirects to frames decapsulated from IPsec.
 	 */
-	if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0 &&
-	    !skb_sec_path(skb)) {
+	n = dst_get_neighbour(dst);
+	if (skb->dev == dst->dev && n && opt->srcrt == 0 && !skb_sec_path(skb)) {
 		struct in6_addr *target = NULL;
 		struct rt6_info *rt;
-		struct neighbour *n = dst->neighbour;
 
 		/*
 		 *	incoming and outgoing devices are the same
@@ -920,8 +920,11 @@ out:
 static int ip6_dst_lookup_tail(struct sock *sk,
 			       struct dst_entry **dst, struct flowi6 *fl6)
 {
-	int err;
 	struct net *net = sock_net(sk);
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+	struct neighbour *n;
+#endif
+	int err;
 
 	if (*dst == NULL)
 		*dst = ip6_route_output(net, sk, fl6);
@@ -947,7 +950,8 @@ static int ip6_dst_lookup_tail(struct sock *sk,
 	 * dst entry and replace it instead with the
 	 * dst entry of the nexthop router
 	 */
-	if ((*dst)->neighbour && !((*dst)->neighbour->nud_state & NUD_VALID)) {
+	n = dst_get_neighbour(*dst);
+	if (n && !(n->nud_state & NUD_VALID)) {
 		struct inet6_ifaddr *ifp;
 		struct flowi6 fl_gw6;
 		int redirect;

net/ipv6/ndisc.c

@@ -1238,7 +1238,7 @@ static void ndisc_router_discovery(struct sk_buff *skb)
 	rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
 
 	if (rt)
-		neigh = rt->dst.neighbour;
+		neigh = dst_get_neighbour(&rt->dst);
 
 	if (rt && lifetime == 0) {
 		neigh_clone(neigh);
@@ -1259,7 +1259,7 @@ static void ndisc_router_discovery(struct sk_buff *skb)
 			return;
 		}
 
-		neigh = rt->dst.neighbour;
+		neigh = dst_get_neighbour(&rt->dst);
 		if (neigh == NULL) {
 			ND_PRINTK0(KERN_ERR
 				   "ICMPv6 RA: %s() got default router without neighbour.\n",

net/ipv6/route.c

@@ -356,7 +356,7 @@ out:
 #ifdef CONFIG_IPV6_ROUTER_PREF
 static void rt6_probe(struct rt6_info *rt)
 {
-	struct neighbour *neigh = rt ? rt->dst.neighbour : NULL;
+	struct neighbour *neigh = rt ? dst_get_neighbour(&rt->dst) : NULL;
 	/*
 	 * Okay, this does not seem to be appropriate
 	 * for now, however, we need to check if it
@@ -404,7 +404,7 @@ static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 
 static inline int rt6_check_neigh(struct rt6_info *rt)
 {
-	struct neighbour *neigh = rt->dst.neighbour;
+	struct neighbour *neigh = dst_get_neighbour(&rt->dst);
 	int m;
 	if (rt->rt6i_flags & RTF_NONEXTHOP ||
 	    !(rt->rt6i_flags & RTF_GATEWAY))
@@ -745,7 +745,7 @@ static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_add
 			dst_free(&rt->dst);
 			return NULL;
 		}
-		rt->dst.neighbour = neigh;
+		dst_set_neighbour(&rt->dst, neigh);
 
 	}
 
@@ -760,7 +760,7 @@ static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, const struct in6_a
 		rt->rt6i_dst.plen = 128;
 		rt->rt6i_flags |= RTF_CACHE;
 		rt->dst.flags |= DST_HOST;
-		rt->dst.neighbour = neigh_clone(ort->dst.neighbour);
+		dst_set_neighbour(&rt->dst, neigh_clone(dst_get_neighbour(&ort->dst)));
 	}
 	return rt;
 }
@@ -794,7 +794,7 @@ restart:
 	dst_hold(&rt->dst);
 	read_unlock_bh(&table->tb6_lock);
 
-	if (!rt->dst.neighbour && !(rt->rt6i_flags & RTF_NONEXTHOP))
+	if (!dst_get_neighbour(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
 		nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
 	else if (!(rt->dst.flags & DST_HOST))
 		nrt = rt6_alloc_clone(rt, &fl6->daddr);
@@ -1058,7 +1058,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
 	}
 
 	rt->rt6i_idev     = idev;
-	rt->dst.neighbour  = neigh;
+	dst_set_neighbour(&rt->dst, neigh);
 	atomic_set(&rt->dst.__refcnt, 1);
 	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
 	rt->dst.output  = ip6_output;
@@ -1338,12 +1338,12 @@ int ip6_route_add(struct fib6_config *cfg)
 		rt->rt6i_prefsrc.plen = 0;
 
 	if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
-		rt->dst.neighbour = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
-		if (IS_ERR(rt->dst.neighbour)) {
-			err = PTR_ERR(rt->dst.neighbour);
-			rt->dst.neighbour = NULL;
+		struct neighbour *n = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
+		if (IS_ERR(n)) {
+			err = PTR_ERR(n);
 			goto out;
 		}
+		dst_set_neighbour(&rt->dst, n);
 	}
 
 	rt->rt6i_flags = cfg->fc_flags;
@@ -1574,7 +1574,7 @@ void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src,
 	dst_confirm(&rt->dst);
 
 	/* Duplicate redirect: silently ignore. */
-	if (neigh == rt->dst.neighbour)
+	if (neigh == dst_get_neighbour(&rt->dst))
 		goto out;
 
 	nrt = ip6_rt_copy(rt);
@@ -1590,7 +1590,7 @@ void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src,
 	nrt->dst.flags |= DST_HOST;
 
 	ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
-	nrt->dst.neighbour = neigh_clone(neigh);
+	dst_set_neighbour(&nrt->dst, neigh_clone(neigh));
 
 	if (ip6_ins_rt(nrt))
 		goto out;
@@ -1670,7 +1670,7 @@ again:
 	   1. It is connected route. Action: COW
 	   2. It is gatewayed route or NONEXTHOP route. Action: clone it.
 	 */
-	if (!rt->dst.neighbour && !(rt->rt6i_flags & RTF_NONEXTHOP))
+	if (!dst_get_neighbour(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
 		nrt = rt6_alloc_cow(rt, daddr, saddr);
 	else
 		nrt = rt6_alloc_clone(rt, daddr);
@@ -2035,7 +2035,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 
 		return ERR_CAST(neigh);
 	}
-	rt->dst.neighbour = neigh;
+	dst_set_neighbour(&rt->dst, neigh);
 
 	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
 	rt->rt6i_dst.plen = 128;
@@ -2400,8 +2400,8 @@ static int rt6_fill_node(struct net *net,
 	if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
 		goto nla_put_failure;
 
-	if (rt->dst.neighbour)
-		NLA_PUT(skb, RTA_GATEWAY, 16, &rt->dst.neighbour->primary_key);
+	if (dst_get_neighbour(&rt->dst))
+		NLA_PUT(skb, RTA_GATEWAY, 16, &dst_get_neighbour(&rt->dst)->primary_key);
 
 	if (rt->dst.dev)
 		NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
@@ -2585,6 +2585,7 @@ struct rt6_proc_arg
 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
 {
 	struct seq_file *m = p_arg;
+	struct neighbour *n;
 
 	seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
 
@@ -2593,9 +2594,9 @@ static int rt6_info_route(struct rt6_info *rt, void *p_arg)
 #else
 	seq_puts(m, "00000000000000000000000000000000 00 ");
 #endif
-
-	if (rt->dst.neighbour) {
-		seq_printf(m, "%pi6", rt->dst.neighbour->primary_key);
+	n = dst_get_neighbour(&rt->dst);
+	if (n) {
+		seq_printf(m, "%pi6", n->primary_key);
 	} else {
 		seq_puts(m, "00000000000000000000000000000000");
 	}

net/ipv6/sit.c

@@ -677,7 +677,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 		struct neighbour *neigh = NULL;
 
 		if (skb_dst(skb))
-			neigh = skb_dst(skb)->neighbour;
+			neigh = dst_get_neighbour(skb_dst(skb));
 
 		if (neigh == NULL) {
 			if (net_ratelimit())
@@ -702,7 +702,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 		struct neighbour *neigh = NULL;
 
 		if (skb_dst(skb))
-			neigh = skb_dst(skb)->neighbour;
+			neigh = dst_get_neighbour(skb_dst(skb));
 
 		if (neigh == NULL) {
 			if (net_ratelimit())