ipv6: Add infrastructure to bind inet_peer objects to routes.

They are only allowed on cached ipv6 routes.
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip6_fib.h

@@ -21,6 +21,7 @@
 #include <net/dst.h>
 #include <net/flow.h>
 #include <net/netlink.h>
+#include <net/inetpeer.h>
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 #define FIB6_TABLE_HASHSZ 256
@@ -109,6 +110,7 @@ struct rt6_info {
 	u32				rt6i_metric;
 
 	struct inet6_dev		*rt6i_idev;
+	struct inet_peer		*rt6i_peer;
 
 #ifdef CONFIG_XFRM
 	u32				rt6i_flow_cache_genid;

include/net/ip6_route.h

@@ -56,6 +56,9 @@ static inline unsigned int rt6_flags2srcprefs(int flags)
 	return (flags >> 3) & 7;
 }
 
+extern void			rt6_bind_peer(struct rt6_info *rt,
+					      int create);
+
 extern void			ip6_route_input(struct sk_buff *skb);
 
 extern struct dst_entry *	ip6_route_output(struct net *net,

net/ipv4/inetpeer.c

@@ -532,6 +532,7 @@ static int compute_total(void)
 {
 	return v4_peers.total + v6_peers.total;
 }
+EXPORT_SYMBOL_GPL(inet_getpeer);
 
 /* Called with local BH disabled. */
 static void peer_check_expire(unsigned long dummy)
@@ -577,3 +578,4 @@ void inet_putpeer(struct inet_peer *p)
 
 	local_bh_enable();
 }
+EXPORT_SYMBOL_GPL(inet_putpeer);

net/ipv6/route.c

@@ -188,11 +188,29 @@ static void ip6_dst_destroy(struct dst_entry *dst)
 {
 	struct rt6_info *rt = (struct rt6_info *)dst;
 	struct inet6_dev *idev = rt->rt6i_idev;
+	struct inet_peer *peer = rt->rt6i_peer;
 
 	if (idev != NULL) {
 		rt->rt6i_idev = NULL;
 		in6_dev_put(idev);
 	}
+	if (peer) {
+		BUG_ON(!(rt->rt6i_flags & RTF_CACHE));
+		rt->rt6i_peer = NULL;
+		inet_putpeer(peer);
+	}
+}
+
+void rt6_bind_peer(struct rt6_info *rt, int create)
+{
+	struct inet_peer *peer;
+
+	if (WARN_ON(!(rt->rt6i_flags & RTF_CACHE)))
+		return;
+
+	peer = inet_getpeer_v6(&rt->rt6i_dst.addr, create);
+	if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
+		inet_putpeer(peer);
 }
 
 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,