VServer 1.9.2 (patch-2.6.8.1-vs1.9.2.diff)

[linux-2.6.git] / net / bridge / br_fdb.c

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 324489d..9406999 100644 (file)
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -73,9 +73,9 @@ static __inline__ int br_mac_hash(const unsigned char *mac)
 
 static __inline__ void fdb_delete(struct net_bridge_fdb_entry *f)
 {
-       hlist_del(&f->hlist);
+       hlist_del_rcu(&f->hlist);
        if (!f->is_static)
-               list_del(&f->age_list);
+               list_del(&f->u.age_list);
 
        br_fdb_put(f);
 }
@@ -85,7 +85,7 @@ void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
        struct net_bridge *br = p->br;
        int i;
        
-       write_lock_bh(&br->hash_lock);
+       spin_lock_bh(&br->hash_lock);
 
        /* Search all chains since old address/hash is unknown */
        for (i = 0; i < BR_HASH_SIZE; i++) {
@@ -117,7 +117,7 @@ void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
        fdb_insert(br, p, newaddr, 1);
 
 
-       write_unlock_bh(&br->hash_lock);
+       spin_unlock_bh(&br->hash_lock);
 }
 
 void br_fdb_cleanup(unsigned long _data)
@@ -126,13 +126,15 @@ void br_fdb_cleanup(unsigned long _data)
        struct list_head *l, *n;
        unsigned long delay;
 
-       write_lock_bh(&br->hash_lock);
+       spin_lock_bh(&br->hash_lock);
        delay = hold_time(br);
 
        list_for_each_safe(l, n, &br->age_list) {
-               struct net_bridge_fdb_entry *f
-                       = list_entry(l, struct net_bridge_fdb_entry, age_list);
-               unsigned long expires = f->ageing_timer + delay;
+               struct net_bridge_fdb_entry *f;
+               unsigned long expires;
+
+               f = list_entry(l, struct net_bridge_fdb_entry, u.age_list);
+               expires = f->ageing_timer + delay;
 
                if (time_before_eq(expires, jiffies)) {
                        WARN_ON(f->is_static);
@@ -144,14 +146,14 @@ void br_fdb_cleanup(unsigned long _data)
                        break;
                }
        }
-       write_unlock_bh(&br->hash_lock);
+       spin_unlock_bh(&br->hash_lock);
 }
 
 void br_fdb_delete_by_port(struct net_bridge *br, struct net_bridge_port *p)
 {
        int i;
 
-       write_lock_bh(&br->hash_lock);
+       spin_lock_bh(&br->hash_lock);
        for (i = 0; i < BR_HASH_SIZE; i++) {
                struct hlist_node *h, *g;
                
@@ -182,37 +184,53 @@ void br_fdb_delete_by_port(struct net_bridge *br, struct net_bridge_port *p)
                skip_delete: ;
                }
        }
-       write_unlock_bh(&br->hash_lock);
+       spin_unlock_bh(&br->hash_lock);
 }
 
-struct net_bridge_fdb_entry *br_fdb_get(struct net_bridge *br, unsigned char *addr)
+/* No locking or refcounting, assumes caller has no preempt (rcu_read_lock) */
+struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
+                                         const unsigned char *addr)
 {
        struct hlist_node *h;
+       struct net_bridge_fdb_entry *fdb;
 
-       read_lock_bh(&br->hash_lock);
-               
-       hlist_for_each(h, &br->hash[br_mac_hash(addr)]) {
-               struct net_bridge_fdb_entry *fdb
-                       = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
-
+       hlist_for_each_entry_rcu(fdb, h, &br->hash[br_mac_hash(addr)], hlist) {
                if (!memcmp(fdb->addr.addr, addr, ETH_ALEN)) {
-                       if (has_expired(br, fdb))
-                               goto ret_null;
-
-                       atomic_inc(&fdb->use_count);
-                       read_unlock_bh(&br->hash_lock);
+                       if (unlikely(has_expired(br, fdb)))
+                               break;
                        return fdb;
                }
        }
- ret_null:
-       read_unlock_bh(&br->hash_lock);
+
        return NULL;
 }
 
+/* Interface used by ATM hook that keeps a ref count */
+struct net_bridge_fdb_entry *br_fdb_get(struct net_bridge *br, 
+                                       unsigned char *addr)
+{
+       struct net_bridge_fdb_entry *fdb;
+
+       rcu_read_lock();
+       fdb = __br_fdb_get(br, addr);
+       if (fdb) 
+               atomic_inc(&fdb->use_count);
+       rcu_read_unlock();
+       return fdb;
+}
+
+static void fdb_rcu_free(struct rcu_head *head)
+{
+       struct net_bridge_fdb_entry *ent
+               = container_of(head, struct net_bridge_fdb_entry, u.rcu);
+       kmem_cache_free(br_fdb_cache, ent);
+}
+
+/* Set entry up for deletion with RCU  */
 void br_fdb_put(struct net_bridge_fdb_entry *ent)
 {
        if (atomic_dec_and_test(&ent->use_count))
-               kmem_cache_free(br_fdb_cache, ent);
+               call_rcu(&ent->u.rcu, fdb_rcu_free);
 }
 
 /*
@@ -229,9 +247,9 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 
        memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 
-       read_lock_bh(&br->hash_lock);
+       rcu_read_lock();
        for (i = 0; i < BR_HASH_SIZE; i++) {
-               hlist_for_each_entry(f, h, &br->hash[i], hlist) {
+               hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
                        if (num >= maxnum)
                                goto out;
 
@@ -255,7 +273,7 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf,
        }
 
  out:
-       read_unlock_bh(&br->hash_lock);
+       rcu_read_unlock();
 
        return num;
 }
@@ -298,7 +316,7 @@ static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
                                return 0;
 
                        /* move to end of age list */
-                       list_del(&fdb->age_list);
+                       list_del(&fdb->u.age_list);
                        goto update;
                }
        }
@@ -309,7 +327,7 @@ static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 
        memcpy(fdb->addr.addr, addr, ETH_ALEN);
        atomic_set(&fdb->use_count, 1);
-       hlist_add_head(&fdb->hlist, &br->hash[hash]);
+       hlist_add_head_rcu(&fdb->hlist, &br->hash[hash]);
 
        if (!timer_pending(&br->gc_timer)) {
                br->gc_timer.expires = jiffies + hold_time(br);
@@ -322,7 +340,7 @@ static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
        fdb->is_static = is_local;
        fdb->ageing_timer = jiffies;
        if (!is_local) 
-               list_add_tail(&fdb->age_list, &br->age_list);
+               list_add_tail(&fdb->u.age_list, &br->age_list);
 
        return 0;
 }
@@ -332,8 +350,8 @@ int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 {
        int ret;
 
-       write_lock_bh(&br->hash_lock);
+       spin_lock_bh(&br->hash_lock);
        ret = fdb_insert(br, source, addr, is_local);
-       write_unlock_bh(&br->hash_lock);
+       spin_unlock_bh(&br->hash_lock);
        return ret;
 }