netfilter: conntrack: move event caching to conntrack extension infrastructure
[safe/jmp/linux-2.6] / net / netfilter / nf_conntrack_ecache.c
index 5516b3e..683281b 100644 (file)
@@ -21,6 +21,7 @@
 
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_extend.h>
 
 static DEFINE_MUTEX(nf_ct_ecache_mutex);
 
@@ -32,94 +33,38 @@ EXPORT_SYMBOL_GPL(nf_expect_event_cb);
 
 /* deliver cached events and clear cache entry - must be called with locally
  * disabled softirqs */
-static inline void
-__nf_ct_deliver_cached_events(struct nf_conntrack_ecache *ecache)
+void nf_ct_deliver_cached_events(struct nf_conn *ct)
 {
+       unsigned long events;
        struct nf_ct_event_notifier *notify;
+       struct nf_conntrack_ecache *e;
 
        rcu_read_lock();
        notify = rcu_dereference(nf_conntrack_event_cb);
        if (notify == NULL)
                goto out_unlock;
 
-       if (nf_ct_is_confirmed(ecache->ct) && !nf_ct_is_dying(ecache->ct)
-           && ecache->events) {
+       e = nf_ct_ecache_find(ct);
+       if (e == NULL)
+               goto out_unlock;
+
+       events = xchg(&e->cache, 0);
+
+       if (nf_ct_is_confirmed(ct) && !nf_ct_is_dying(ct) && events) {
                struct nf_ct_event item = {
-                       .ct     = ecache->ct,
+                       .ct     = ct,
                        .pid    = 0,
                        .report = 0
                };
 
-               notify->fcn(ecache->events, &item);
+               notify->fcn(events, &item);
        }
 
-       ecache->events = 0;
-       nf_ct_put(ecache->ct);
-       ecache->ct = NULL;
-
 out_unlock:
        rcu_read_unlock();
 }
-
-/* Deliver all cached events for a particular conntrack. This is called
- * by code prior to async packet handling for freeing the skb */
-void nf_ct_deliver_cached_events(const struct nf_conn *ct)
-{
-       struct net *net = nf_ct_net(ct);
-       struct nf_conntrack_ecache *ecache;
-
-       local_bh_disable();
-       ecache = per_cpu_ptr(net->ct.ecache, raw_smp_processor_id());
-       if (ecache->ct == ct)
-               __nf_ct_deliver_cached_events(ecache);
-       local_bh_enable();
-}
 EXPORT_SYMBOL_GPL(nf_ct_deliver_cached_events);
 
-/* Deliver cached events for old pending events, if current conntrack != old */
-void __nf_ct_event_cache_init(struct nf_conn *ct)
-{
-       struct net *net = nf_ct_net(ct);
-       struct nf_conntrack_ecache *ecache;
-
-       /* take care of delivering potentially old events */
-       ecache = per_cpu_ptr(net->ct.ecache, raw_smp_processor_id());
-       BUG_ON(ecache->ct == ct);
-       if (ecache->ct)
-               __nf_ct_deliver_cached_events(ecache);
-       /* initialize for this conntrack/packet */
-       ecache->ct = ct;
-       nf_conntrack_get(&ct->ct_general);
-}
-EXPORT_SYMBOL_GPL(__nf_ct_event_cache_init);
-
-/* flush the event cache - touches other CPU's data and must not be called
- * while packets are still passing through the code */
-void nf_ct_event_cache_flush(struct net *net)
-{
-       struct nf_conntrack_ecache *ecache;
-       int cpu;
-
-       for_each_possible_cpu(cpu) {
-               ecache = per_cpu_ptr(net->ct.ecache, cpu);
-               if (ecache->ct)
-                       nf_ct_put(ecache->ct);
-       }
-}
-
-int nf_conntrack_ecache_init(struct net *net)
-{
-       net->ct.ecache = alloc_percpu(struct nf_conntrack_ecache);
-       if (!net->ct.ecache)
-               return -ENOMEM;
-       return 0;
-}
-
-void nf_conntrack_ecache_fini(struct net *net)
-{
-       free_percpu(net->ct.ecache);
-}
-
 int nf_conntrack_register_notifier(struct nf_ct_event_notifier *new)
 {
        int ret = 0;
@@ -185,3 +130,107 @@ void nf_ct_expect_unregister_notifier(struct nf_exp_event_notifier *new)
        mutex_unlock(&nf_ct_ecache_mutex);
 }
 EXPORT_SYMBOL_GPL(nf_ct_expect_unregister_notifier);
+
+#define NF_CT_EVENTS_DEFAULT 1
+static int nf_ct_events __read_mostly = NF_CT_EVENTS_DEFAULT;
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table event_sysctl_table[] = {
+       {
+               .ctl_name       = CTL_UNNUMBERED,
+               .procname       = "nf_conntrack_events",
+               .data           = &init_net.ct.sysctl_events,
+               .maxlen         = sizeof(unsigned int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec,
+       },
+       {}
+};
+#endif /* CONFIG_SYSCTL */
+
+static struct nf_ct_ext_type event_extend __read_mostly = {
+       .len    = sizeof(struct nf_conntrack_ecache),
+       .align  = __alignof__(struct nf_conntrack_ecache),
+       .id     = NF_CT_EXT_ECACHE,
+};
+
+#ifdef CONFIG_SYSCTL
+static int nf_conntrack_event_init_sysctl(struct net *net)
+{
+       struct ctl_table *table;
+
+       table = kmemdup(event_sysctl_table, sizeof(event_sysctl_table),
+                       GFP_KERNEL);
+       if (!table)
+               goto out;
+
+       table[0].data = &net->ct.sysctl_events;
+
+       net->ct.event_sysctl_header =
+               register_net_sysctl_table(net,
+                                         nf_net_netfilter_sysctl_path, table);
+       if (!net->ct.event_sysctl_header) {
+               printk(KERN_ERR "nf_ct_event: can't register to sysctl.\n");
+               goto out_register;
+       }
+       return 0;
+
+out_register:
+       kfree(table);
+out:
+       return -ENOMEM;
+}
+
+static void nf_conntrack_event_fini_sysctl(struct net *net)
+{
+       struct ctl_table *table;
+
+       table = net->ct.event_sysctl_header->ctl_table_arg;
+       unregister_net_sysctl_table(net->ct.event_sysctl_header);
+       kfree(table);
+}
+#else
+static int nf_conntrack_event_init_sysctl(struct net *net)
+{
+       return 0;
+}
+
+static void nf_conntrack_event_fini_sysctl(struct net *net)
+{
+}
+#endif /* CONFIG_SYSCTL */
+
+int nf_conntrack_ecache_init(struct net *net)
+{
+       int ret;
+
+       net->ct.sysctl_events = nf_ct_events;
+
+       if (net_eq(net, &init_net)) {
+               ret = nf_ct_extend_register(&event_extend);
+               if (ret < 0) {
+                       printk(KERN_ERR "nf_ct_event: Unable to register "
+                                       "event extension.\n");
+                       goto out_extend_register;
+               }
+       }
+
+       ret = nf_conntrack_event_init_sysctl(net);
+       if (ret < 0)
+               goto out_sysctl;
+
+       return 0;
+
+out_sysctl:
+       if (net_eq(net, &init_net))
+               nf_ct_extend_unregister(&event_extend);
+out_extend_register:
+       return ret;
+}
+
+void nf_conntrack_ecache_fini(struct net *net)
+{
+       nf_conntrack_event_fini_sysctl(net);
+       if (net_eq(net, &init_net))
+               nf_ct_extend_unregister(&event_extend);
+}