net: Add initial_ref arg to dst_alloc().

[~andy/linux] / net / ipv6 / route.c

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 373bd0416f69f9ad7e4645eebb574a3ec4eb4127..7946b53692da1ae28d5c882c8b06e913b684cd5e 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -72,8 +72,6 @@
 #define RT6_TRACE(x...) do { ; } while (0)
 #endif
 
-#define CLONE_OFFLINK_ROUTE 0
-
 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
 static struct dst_entry        *ip6_dst_check(struct dst_entry *dst, u32 cookie);
 static unsigned int     ip6_default_advmss(const struct dst_entry *dst);
@@ -99,6 +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),
@@ -107,6 +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            =       ipv6_cow_metrics,
        .destroy                =       ip6_dst_destroy,
        .ifdown                 =       ip6_dst_ifdown,
        .negative_advice        =       ip6_negative_advice,
@@ -115,6 +144,11 @@ static struct dst_ops ip6_dst_ops_template = {
        .local_out              =       __ip6_local_out,
 };
 
+static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
+{
+       return 0;
+}
+
 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
 {
 }
@@ -124,9 +158,14 @@ static struct dst_ops ip6_dst_blackhole_ops = {
        .protocol               =       cpu_to_be16(ETH_P_IPV6),
        .destroy                =       ip6_dst_destroy,
        .check                  =       ip6_dst_check,
+       .default_mtu            =       ip6_blackhole_default_mtu,
        .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 };
 
+static const u32 ip6_template_metrics[RTAX_MAX] = {
+       [RTAX_HOPLIMIT - 1] = 255,
+};
+
 static struct rt6_info ip6_null_entry_template = {
        .dst = {
                .__refcnt       = ATOMIC_INIT(1),
@@ -182,7 +221,7 @@ static struct rt6_info ip6_blk_hole_entry_template = {
 /* allocate dst with ip6_dst_ops */
 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops)
 {
-       return (struct rt6_info *)dst_alloc(ops);
+       return (struct rt6_info *)dst_alloc(ops, 0);
 }
 
 static void ip6_dst_destroy(struct dst_entry *dst)
@@ -196,22 +235,27 @@ static void ip6_dst_destroy(struct dst_entry *dst)
                in6_dev_put(idev);
        }
        if (peer) {
-               BUG_ON(!(rt->rt6i_flags & RTF_CACHE));
                rt->rt6i_peer = NULL;
                inet_putpeer(peer);
        }
 }
 
+static atomic_t __rt6_peer_genid = ATOMIC_INIT(0);
+
+static u32 rt6_peer_genid(void)
+{
+       return atomic_read(&__rt6_peer_genid);
+}
+
 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);
+       else
+               rt->rt6i_peer_genid = rt6_peer_genid();
 }
 
 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
@@ -738,13 +782,8 @@ restart:
 
        if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
                nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
-       else {
-#if CLONE_OFFLINK_ROUTE
+       else
                nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
-#else
-               goto out2;
-#endif
-       }
 
        dst_release(&rt->dst);
        rt = nrt ? : net->ipv6.ip6_null_entry;
@@ -834,13 +873,12 @@ int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl
 {
        struct rt6_info *ort = (struct rt6_info *) *dstp;
        struct rt6_info *rt = (struct rt6_info *)
-               dst_alloc(&ip6_dst_blackhole_ops);
+               dst_alloc(&ip6_dst_blackhole_ops, 1);
        struct dst_entry *new = NULL;
 
        if (rt) {
                new = &rt->dst;
 
-               atomic_set(&new->__refcnt, 1);
                new->__use = 1;
                new->input = dst_discard;
                new->output = dst_discard;
@@ -882,9 +920,14 @@ static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
 
        rt = (struct rt6_info *) dst;
 
-       if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
+       if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
+               if (rt->rt6i_peer_genid != rt6_peer_genid()) {
+                       if (!rt->rt6i_peer)
+                               rt6_bind_peer(rt, 0);
+                       rt->rt6i_peer_genid = rt6_peer_genid();
+               }
                return dst;
-
+       }
        return NULL;
 }
 
@@ -935,7 +978,6 @@ static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
                        dst_metric_set(dst, RTAX_FEATURES, features);
                }
                dst_metric_set(dst, RTAX_MTU, mtu);
-               call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
        }
 }
 
@@ -2688,7 +2730,8 @@ static int __net_init ip6_route_net_init(struct net *net)
        net->ipv6.ip6_null_entry->dst.path =
                (struct dst_entry *)net->ipv6.ip6_null_entry;
        net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
-       dst_metric_set(&net->ipv6.ip6_null_entry->dst, RTAX_HOPLIMIT, 255);
+       dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
+                        ip6_template_metrics, true);
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
        net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
@@ -2699,7 +2742,8 @@ static int __net_init ip6_route_net_init(struct net *net)
        net->ipv6.ip6_prohibit_entry->dst.path =
                (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
        net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
-       dst_metric_set(&net->ipv6.ip6_prohibit_entry->dst, RTAX_HOPLIMIT, 255);
+       dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
+                        ip6_template_metrics, true);
 
        net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
                                               sizeof(*net->ipv6.ip6_blk_hole_entry),
@@ -2709,7 +2753,8 @@ static int __net_init ip6_route_net_init(struct net *net)
        net->ipv6.ip6_blk_hole_entry->dst.path =
                (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
        net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
-       dst_metric_set(&net->ipv6.ip6_blk_hole_entry->dst, RTAX_HOPLIMIT, 255);
+       dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
+                        ip6_template_metrics, true);
 #endif
 
        net->ipv6.sysctl.flush_delay = 0;