Merge tag 'sunxi-fixes-for-4.3' of https://git.kernel.org/pub/scm/linux/kernel/git...

[linux-drm-fsl-dcu.git] / net / ipv6 / ip6_tunnel.c

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 851cf6d1eb45a76cfa9f6c04255ba0344c76ebb7..eabffbb89795d921b0977989345b25d81f553ee0 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -126,45 +126,48 @@ static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  * Locking : hash tables are protected by RCU and RTNL
  */
 
-static void __ip6_tnl_per_cpu_dst_set(struct ip6_tnl_dst *idst,
-                                     struct dst_entry *dst)
+static void ip6_tnl_per_cpu_dst_set(struct ip6_tnl_dst *idst,
+                                   struct dst_entry *dst)
 {
-       dst_release(idst->dst);
+       write_seqlock_bh(&idst->lock);
+       dst_release(rcu_dereference_protected(
+                           idst->dst,
+                           lockdep_is_held(&idst->lock.lock)));
        if (dst) {
                dst_hold(dst);
                idst->cookie = rt6_get_cookie((struct rt6_info *)dst);
        } else {
                idst->cookie = 0;
        }
-       idst->dst = dst;
-}
-
-static void ip6_tnl_per_cpu_dst_set(struct ip6_tnl_dst *idst,
-                                   struct dst_entry *dst)
-{
-
-       spin_lock_bh(&idst->lock);
-       __ip6_tnl_per_cpu_dst_set(idst, dst);
-       spin_unlock_bh(&idst->lock);
+       rcu_assign_pointer(idst->dst, dst);
+       write_sequnlock_bh(&idst->lock);
 }
 
 struct dst_entry *ip6_tnl_dst_get(struct ip6_tnl *t)
 {
        struct ip6_tnl_dst *idst;
        struct dst_entry *dst;
+       unsigned int seq;
+       u32 cookie;
 
        idst = raw_cpu_ptr(t->dst_cache);
-       spin_lock_bh(&idst->lock);
-       dst = idst->dst;
-       if (dst) {
-               if (!dst->obsolete || dst->ops->check(dst, idst->cookie)) {
-                       dst_hold(idst->dst);
-               } else {
-                       __ip6_tnl_per_cpu_dst_set(idst, NULL);
-                       dst = NULL;
-               }
+
+       rcu_read_lock();
+       do {
+               seq = read_seqbegin(&idst->lock);
+               dst = rcu_dereference(idst->dst);
+               cookie = idst->cookie;
+       } while (read_seqretry(&idst->lock, seq));
+
+       if (dst && !atomic_inc_not_zero(&dst->__refcnt))
+               dst = NULL;
+       rcu_read_unlock();
+
+       if (dst && dst->obsolete && !dst->ops->check(dst, cookie)) {
+               ip6_tnl_per_cpu_dst_set(idst, NULL);
+               dst_release(dst);
+               dst = NULL;
        }
-       spin_unlock_bh(&idst->lock);
        return dst;
 }
 EXPORT_SYMBOL_GPL(ip6_tnl_dst_get);
@@ -204,7 +207,7 @@ int ip6_tnl_dst_init(struct ip6_tnl *t)
                return -ENOMEM;
 
        for_each_possible_cpu(i)
-               spin_lock_init(&per_cpu_ptr(t->dst_cache, i)->lock);
+               seqlock_init(&per_cpu_ptr(t->dst_cache, i)->lock);
 
        return 0;
 }
@@ -566,14 +569,14 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
                struct ipv6_tlv_tnl_enc_lim *tel;
                __u32 mtu;
        case ICMPV6_DEST_UNREACH:
-               net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
-                                    t->parms.name);
+               net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
+                                   t->parms.name);
                rel_msg = 1;
                break;
        case ICMPV6_TIME_EXCEED:
                if ((*code) == ICMPV6_EXC_HOPLIMIT) {
-                       net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
-                                            t->parms.name);
+                       net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
+                                           t->parms.name);
                        rel_msg = 1;
                }
                break;
@@ -585,13 +588,13 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
                if (teli && teli == *info - 2) {
                        tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
                        if (tel->encap_limit == 0) {
-                               net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
-                                                    t->parms.name);
+                               net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
+                                                   t->parms.name);
                                rel_msg = 1;
                        }
                } else {
-                       net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
-                                            t->parms.name);
+                       net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
+                                           t->parms.name);
                }
                break;
        case ICMPV6_PKT_TOOBIG: