diff options
| -rw-r--r-- | net/ipv6/ip6_tunnel.c | 44 |
1 files changed, 25 insertions, 19 deletions
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index c595bbe1ed99..670c291d2567 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -88,8 +88,10 @@ struct ip6_tnl_net { struct ip6_tnl **tnls[2]; }; -/* lock for the tunnel lists */ -static DEFINE_RWLOCK(ip6_tnl_lock); +/* + * Locking : hash tables are protected by RCU and a spinlock + */ +static DEFINE_SPINLOCK(ip6_tnl_lock); static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t) { @@ -130,6 +132,9 @@ static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst) * else %NULL **/ +#define for_each_ip6_tunnel_rcu(start) \ + for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) + static struct ip6_tnl * ip6_tnl_lookup(struct net *net, struct in6_addr *remote, struct in6_addr *local) { @@ -138,13 +143,14 @@ ip6_tnl_lookup(struct net *net, struct in6_addr *remote, struct in6_addr *local) struct ip6_tnl *t; struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); - for (t = ip6n->tnls_r_l[h0 ^ h1]; t; t = t->next) { + for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[h0 ^ h1]) { if (ipv6_addr_equal(local, &t->parms.laddr) && ipv6_addr_equal(remote, &t->parms.raddr) && (t->dev->flags & IFF_UP)) return t; } - if ((t = ip6n->tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP)) + t = rcu_dereference(ip6n->tnls_wc[0]); + if (t && (t->dev->flags & IFF_UP)) return t; return NULL; @@ -186,10 +192,10 @@ ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) { struct ip6_tnl **tp = ip6_tnl_bucket(ip6n, &t->parms); + spin_lock_bh(&ip6_tnl_lock); t->next = *tp; - write_lock_bh(&ip6_tnl_lock); - *tp = t; - write_unlock_bh(&ip6_tnl_lock); + rcu_assign_pointer(*tp, t); + spin_unlock_bh(&ip6_tnl_lock); } /** @@ -204,9 +210,9 @@ ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) for (tp = ip6_tnl_bucket(ip6n, &t->parms); *tp; tp = &(*tp)->next) { if (t == *tp) { - write_lock_bh(&ip6_tnl_lock); + spin_lock_bh(&ip6_tnl_lock); *tp = t->next; - write_unlock_bh(&ip6_tnl_lock); + spin_unlock_bh(&ip6_tnl_lock); break; } } @@ -313,9 +319,9 @@ ip6_tnl_dev_uninit(struct net_device *dev) struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); if (dev == ip6n->fb_tnl_dev) { - write_lock_bh(&ip6_tnl_lock); + spin_lock_bh(&ip6_tnl_lock); ip6n->tnls_wc[0] = NULL; - write_unlock_bh(&ip6_tnl_lock); + spin_unlock_bh(&ip6_tnl_lock); } else { ip6_tnl_unlink(ip6n, t); } @@ -409,7 +415,7 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, in trouble since we might need the source address for further processing of the error. */ - read_lock(&ip6_tnl_lock); + rcu_read_lock(); if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr)) == NULL) goto out; @@ -482,7 +488,7 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, *msg = rel_msg; out: - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); return err; } @@ -693,23 +699,23 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, struct ip6_tnl *t; struct ipv6hdr *ipv6h = ipv6_hdr(skb); - read_lock(&ip6_tnl_lock); + rcu_read_lock(); if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr)) != NULL) { if (t->parms.proto != ipproto && t->parms.proto != 0) { - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); goto discard; } if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); goto discard; } if (!ip6_tnl_rcv_ctl(t)) { t->dev->stats.rx_dropped++; - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); goto discard; } secpath_reset(skb); @@ -727,10 +733,10 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, t->dev->stats.rx_packets++; t->dev->stats.rx_bytes += skb->len; netif_rx(skb); - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); return 0; } - read_unlock(&ip6_tnl_lock); + rcu_read_unlock(); return 1; discard: |