[SK_BUFF]: Introduce ipv6_hdr(), remove skb->nh.ipv6h

[safe/jmp/linux-2.6] / net / netfilter / nf_conntrack_proto.c

diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
index 1a61b72..456155f 100644 (file)
--- a/net/netfilter/nf_conntrack_proto.c
+++ b/net/netfilter/nf_conntrack_proto.c
@@ -66,7 +66,7 @@ __nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
        if (unlikely(l3proto >= AF_MAX || nf_ct_protos[l3proto] == NULL))
                return &nf_conntrack_l4proto_generic;
 
-       return nf_ct_protos[l3proto][l4proto];
+       return rcu_dereference(nf_ct_protos[l3proto][l4proto]);
 }
 EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);
 
@@ -77,11 +77,11 @@ nf_ct_l4proto_find_get(u_int16_t l3proto, u_int8_t l4proto)
 {
        struct nf_conntrack_l4proto *p;
 
-       preempt_disable();
+       rcu_read_lock();
        p = __nf_ct_l4proto_find(l3proto, l4proto);
        if (!try_module_get(p->me))
                p = &nf_conntrack_l4proto_generic;
-       preempt_enable();
+       rcu_read_unlock();
 
        return p;
 }
@@ -98,11 +98,11 @@ nf_ct_l3proto_find_get(u_int16_t l3proto)
 {
        struct nf_conntrack_l3proto *p;
 
-       preempt_disable();
+       rcu_read_lock();
        p = __nf_ct_l3proto_find(l3proto);
        if (!try_module_get(p->me))
                p = &nf_conntrack_l3proto_generic;
-       preempt_enable();
+       rcu_read_unlock();
 
        return p;
 }
@@ -137,10 +137,8 @@ void nf_ct_l3proto_module_put(unsigned short l3proto)
 {
        struct nf_conntrack_l3proto *p;
 
-       preempt_disable();
+       /* rcu_read_lock not necessary since the caller holds a reference */
        p = __nf_ct_l3proto_find(l3proto);
-       preempt_enable();
-
        module_put(p->me);
 }
 EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);
@@ -202,7 +200,7 @@ int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto)
                ret = -EBUSY;
                goto out_unlock;
        }
-       nf_ct_l3protos[proto->l3proto] = proto;
+       rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);
        write_unlock_bh(&nf_conntrack_lock);
 
        ret = nf_ct_l3proto_register_sysctl(proto);
@@ -217,35 +215,21 @@ out:
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register);
 
-int nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
+void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
 {
-       int ret = 0;
-
-       if (proto->l3proto >= AF_MAX) {
-               ret = -EBUSY;
-               goto out;
-       }
+       BUG_ON(proto->l3proto >= AF_MAX);
 
        write_lock_bh(&nf_conntrack_lock);
-       if (nf_ct_l3protos[proto->l3proto] != proto) {
-               write_unlock_bh(&nf_conntrack_lock);
-               ret = -EBUSY;
-               goto out;
-       }
-
-       nf_ct_l3protos[proto->l3proto] = &nf_conntrack_l3proto_generic;
+       BUG_ON(nf_ct_l3protos[proto->l3proto] != proto);
+       rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
+                          &nf_conntrack_l3proto_generic);
        write_unlock_bh(&nf_conntrack_lock);
+       synchronize_rcu();
 
        nf_ct_l3proto_unregister_sysctl(proto);
 
-       /* Somebody could be still looking at the proto in bh. */
-       synchronize_net();
-
        /* Remove all contrack entries for this protocol */
        nf_ct_iterate_cleanup(kill_l3proto, proto);
-
-out:
-       return ret;
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister);
 
@@ -356,7 +340,7 @@ retry:
                goto retry;
        }
 
-       nf_ct_protos[l4proto->l3proto][l4proto->l4proto] = l4proto;
+       rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto], l4proto);
        write_unlock_bh(&nf_conntrack_lock);
 
        ret = nf_ct_l4proto_register_sysctl(l4proto);
@@ -371,40 +355,25 @@ out:
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register);
 
-int nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
+void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
 {
-       int ret = 0;
-
-       if (l4proto->l3proto >= PF_MAX) {
-               ret = -EBUSY;
-               goto out;
-       }
+       BUG_ON(l4proto->l3proto >= PF_MAX);
 
        if (l4proto == &nf_conntrack_l4proto_generic) {
                nf_ct_l4proto_unregister_sysctl(l4proto);
-               goto out;
+               return;
        }
 
        write_lock_bh(&nf_conntrack_lock);
-       if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto]
-           != l4proto) {
-               write_unlock_bh(&nf_conntrack_lock);
-               ret = -EBUSY;
-               goto out;
-       }
-       nf_ct_protos[l4proto->l3proto][l4proto->l4proto]
-               = &nf_conntrack_l4proto_generic;
+       BUG_ON(nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != l4proto);
+       rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
+                          &nf_conntrack_l4proto_generic);
        write_unlock_bh(&nf_conntrack_lock);
+       synchronize_rcu();
 
        nf_ct_l4proto_unregister_sysctl(l4proto);
 
-       /* Somebody could be still looking at the proto in bh. */
-       synchronize_net();
-
        /* Remove all contrack entries for this protocol */
        nf_ct_iterate_cleanup(kill_l4proto, l4proto);
-
-out:
-       return ret;
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);