net: Store ipv4/ipv6 COW'd metrics in inetpeer cache.

Please note that the IPSEC dst entry metrics keep using
the generic metrics COW'ing mechanism using kmalloc/kfree.

This gives the IPSEC routes an opportunity to use metrics
which are unique to their encapsulated paths.

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

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 980030d..68cee35 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -154,25 +154,30 @@ static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 
 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
 {
-       u32 *p = kmalloc(sizeof(u32) * RTAX_MAX, GFP_ATOMIC);
+       struct rtable *rt = (struct rtable *) dst;
+       struct inet_peer *peer;
+       u32 *p = NULL;
+
+       if (!rt->peer)
+               rt_bind_peer(rt, 1);
 
-       if (p) {
+       peer = rt->peer;
+       if (peer) {
                u32 *old_p = __DST_METRICS_PTR(old);
                unsigned long prev, new;
 
-               memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
+               p = peer->metrics;
+               if (inet_metrics_new(peer))
+                       memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
 
                new = (unsigned long) p;
                prev = cmpxchg(&dst->_metrics, old, new);
 
                if (prev != old) {
-                       kfree(p);
                        p = __DST_METRICS_PTR(prev);
                        if (prev & DST_METRICS_READ_ONLY)
                                p = NULL;
                } else {
-                       struct rtable *rt = (struct rtable *) dst;
-
                        if (rt->fi) {
                                fib_info_put(rt->fi);
                                rt->fi = NULL;
@@ -1753,7 +1758,6 @@ static void ipv4_dst_destroy(struct dst_entry *dst)
        struct rtable *rt = (struct rtable *) dst;
        struct inet_peer *peer = rt->peer;
 
-       dst_destroy_metrics_generic(dst);
        if (rt->fi) {
                fib_info_put(rt->fi);
                rt->fi = NULL;

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 691798c..72609f1 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -97,6 +97,36 @@ static struct rt6_info *rt6_get_route_info(struct net *net,
                                           struct in6_addr *gwaddr, int ifindex);
 #endif
 
+static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
+{
+       struct rt6_info *rt = (struct rt6_info *) dst;
+       struct inet_peer *peer;
+       u32 *p = NULL;
+
+       if (!rt->rt6i_peer)
+               rt6_bind_peer(rt, 1);
+
+       peer = rt->rt6i_peer;
+       if (peer) {
+               u32 *old_p = __DST_METRICS_PTR(old);
+               unsigned long prev, new;
+
+               p = peer->metrics;
+               if (inet_metrics_new(peer))
+                       memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
+
+               new = (unsigned long) p;
+               prev = cmpxchg(&dst->_metrics, old, new);
+
+               if (prev != old) {
+                       p = __DST_METRICS_PTR(prev);
+                       if (prev & DST_METRICS_READ_ONLY)
+                               p = NULL;
+               }
+       }
+       return p;
+}
+
 static struct dst_ops ip6_dst_ops_template = {
        .family                 =       AF_INET6,
        .protocol               =       cpu_to_be16(ETH_P_IPV6),
@@ -105,7 +135,7 @@ static struct dst_ops ip6_dst_ops_template = {
        .check                  =       ip6_dst_check,
        .default_advmss         =       ip6_default_advmss,
        .default_mtu            =       ip6_default_mtu,
-       .cow_metrics            =       dst_cow_metrics_generic,
+       .cow_metrics            =       ipv6_cow_metrics,
        .destroy                =       ip6_dst_destroy,
        .ifdown                 =       ip6_dst_ifdown,
        .negative_advice        =       ip6_negative_advice,
@@ -198,7 +228,6 @@ static void ip6_dst_destroy(struct dst_entry *dst)
                rt->rt6i_idev = NULL;
                in6_dev_put(idev);
        }
-       dst_destroy_metrics_generic(dst);
        if (peer) {
                rt->rt6i_peer = NULL;
                inet_putpeer(peer);