Merge remote-tracking branches 'asoc/fix/tlv320aic3x' and 'asoc/fix/wm8962' into...
[linux-drm-fsl-dcu.git] / net / ipv6 / ip6_tunnel.c
index b0ab420612bcc30efd5e58a30bdfb5e730e88b0e..eabffbb89795d921b0977989345b25d81f553ee0 100644 (file)
@@ -126,36 +126,92 @@ static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  * Locking : hash tables are protected by RCU and RTNL
  */
 
-struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
+static void ip6_tnl_per_cpu_dst_set(struct ip6_tnl_dst *idst,
+                                   struct dst_entry *dst)
 {
-       struct dst_entry *dst = t->dst_cache;
+       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;
+       }
+       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;
 
-       if (dst && dst->obsolete &&
-           !dst->ops->check(dst, t->dst_cookie)) {
-               t->dst_cache = NULL;
+       idst = raw_cpu_ptr(t->dst_cache);
+
+       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);
-               return NULL;
+               dst = NULL;
        }
-
        return dst;
 }
-EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_get);
 
 void ip6_tnl_dst_reset(struct ip6_tnl *t)
 {
-       dst_release(t->dst_cache);
-       t->dst_cache = NULL;
+       int i;
+
+       for_each_possible_cpu(i)
+               ip6_tnl_per_cpu_dst_set(raw_cpu_ptr(t->dst_cache), NULL);
 }
 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
 
-void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
+void ip6_tnl_dst_set(struct ip6_tnl *t, struct dst_entry *dst)
+{
+       ip6_tnl_per_cpu_dst_set(raw_cpu_ptr(t->dst_cache), dst);
+
+}
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_set);
+
+void ip6_tnl_dst_destroy(struct ip6_tnl *t)
 {
-       struct rt6_info *rt = (struct rt6_info *) dst;
-       t->dst_cookie = rt6_get_cookie(rt);
-       dst_release(t->dst_cache);
-       t->dst_cache = dst;
+       if (!t->dst_cache)
+               return;
+
+       ip6_tnl_dst_reset(t);
+       free_percpu(t->dst_cache);
 }
-EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_destroy);
+
+int ip6_tnl_dst_init(struct ip6_tnl *t)
+{
+       int i;
+
+       t->dst_cache = alloc_percpu(struct ip6_tnl_dst);
+       if (!t->dst_cache)
+               return -ENOMEM;
+
+       for_each_possible_cpu(i)
+               seqlock_init(&per_cpu_ptr(t->dst_cache, i)->lock);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_init);
 
 /**
  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
@@ -271,6 +327,9 @@ ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 
 static void ip6_dev_free(struct net_device *dev)
 {
+       struct ip6_tnl *t = netdev_priv(dev);
+
+       ip6_tnl_dst_destroy(t);
        free_percpu(dev->tstats);
        free_netdev(dev);
 }
@@ -510,14 +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;
@@ -529,13 +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:
@@ -1010,23 +1069,23 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
                memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
                neigh_release(neigh);
        } else if (!fl6->flowi6_mark)
-               dst = ip6_tnl_dst_check(t);
+               dst = ip6_tnl_dst_get(t);
 
        if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
                goto tx_err_link_failure;
 
        if (!dst) {
-               ndst = ip6_route_output(net, NULL, fl6);
+               dst = ip6_route_output(net, NULL, fl6);
 
-               if (ndst->error)
+               if (dst->error)
                        goto tx_err_link_failure;
-               ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
-               if (IS_ERR(ndst)) {
-                       err = PTR_ERR(ndst);
-                       ndst = NULL;
+               dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
+               if (IS_ERR(dst)) {
+                       err = PTR_ERR(dst);
+                       dst = NULL;
                        goto tx_err_link_failure;
                }
-               dst = ndst;
+               ndst = dst;
        }
 
        tdev = dst->dev;
@@ -1072,12 +1131,11 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
                consume_skb(skb);
                skb = new_skb;
        }
-       if (fl6->flowi6_mark) {
-               skb_dst_set(skb, dst);
-               ndst = NULL;
-       } else {
-               skb_dst_set_noref(skb, dst);
-       }
+
+       if (!fl6->flowi6_mark && ndst)
+               ip6_tnl_dst_set(t, ndst);
+       skb_dst_set(skb, dst);
+
        skb->transport_header = skb->network_header;
 
        proto = fl6->flowi6_proto;
@@ -1101,14 +1159,12 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
        ipv6h->saddr = fl6->saddr;
        ipv6h->daddr = fl6->daddr;
        ip6tunnel_xmit(NULL, skb, dev);
-       if (ndst)
-               ip6_tnl_dst_store(t, ndst);
        return 0;
 tx_err_link_failure:
        stats->tx_carrier_errors++;
        dst_link_failure(skb);
 tx_err_dst_release:
-       dst_release(ndst);
+       dst_release(dst);
        return err;
 }
 
@@ -1573,12 +1629,21 @@ static inline int
 ip6_tnl_dev_init_gen(struct net_device *dev)
 {
        struct ip6_tnl *t = netdev_priv(dev);
+       int ret;
 
        t->dev = dev;
        t->net = dev_net(dev);
        dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
        if (!dev->tstats)
                return -ENOMEM;
+
+       ret = ip6_tnl_dst_init(t);
+       if (ret) {
+               free_percpu(dev->tstats);
+               dev->tstats = NULL;
+               return ret;
+       }
+
        return 0;
 }