Merge branches 'pm-core', 'pm-qos', 'pm-domains' and 'pm-opp'

[linux.git] / net / packet / af_packet.c

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index d56ee46b11fc9524e457e5fe8adf10c105a66ab6..70f5b6a4683c29351284e3385f56caf1bce37ac7 100644 (file)
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1497,6 +1497,8 @@ static void __fanout_link(struct sock *sk, struct packet_sock *po)
        f->arr[f->num_members] = sk;
        smp_wmb();
        f->num_members++;
+       if (f->num_members == 1)
+               dev_add_pack(&f->prot_hook);
        spin_unlock(&f->lock);
 }
 
@@ -1513,6 +1515,8 @@ static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
        BUG_ON(i >= f->num_members);
        f->arr[i] = f->arr[f->num_members - 1];
        f->num_members--;
+       if (f->num_members == 0)
+               __dev_remove_pack(&f->prot_hook);
        spin_unlock(&f->lock);
 }
 
@@ -1619,6 +1623,7 @@ static void fanout_release_data(struct packet_fanout *f)
 
 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
 {
+       struct packet_rollover *rollover = NULL;
        struct packet_sock *po = pkt_sk(sk);
        struct packet_fanout *f, *match;
        u8 type = type_flags & 0xff;
@@ -1641,23 +1646,28 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
                return -EINVAL;
        }
 
+       mutex_lock(&fanout_mutex);
+
+       err = -EINVAL;
        if (!po->running)
-               return -EINVAL;
+               goto out;
 
+       err = -EALREADY;
        if (po->fanout)
-               return -EALREADY;
+               goto out;
 
        if (type == PACKET_FANOUT_ROLLOVER ||
            (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
-               po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
-               if (!po->rollover)
-                       return -ENOMEM;
-               atomic_long_set(&po->rollover->num, 0);
-               atomic_long_set(&po->rollover->num_huge, 0);
-               atomic_long_set(&po->rollover->num_failed, 0);
+               err = -ENOMEM;
+               rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
+               if (!rollover)
+                       goto out;
+               atomic_long_set(&rollover->num, 0);
+               atomic_long_set(&rollover->num_huge, 0);
+               atomic_long_set(&rollover->num_failed, 0);
+               po->rollover = rollover;
        }
 
-       mutex_lock(&fanout_mutex);
        match = NULL;
        list_for_each_entry(f, &fanout_list, list) {
                if (f->id == id &&
@@ -1687,7 +1697,6 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
                match->prot_hook.func = packet_rcv_fanout;
                match->prot_hook.af_packet_priv = match;
                match->prot_hook.id_match = match_fanout_group;
-               dev_add_pack(&match->prot_hook);
                list_add(&match->list, &fanout_list);
        }
        err = -EINVAL;
@@ -1704,36 +1713,40 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
                }
        }
 out:
-       mutex_unlock(&fanout_mutex);
-       if (err) {
-               kfree(po->rollover);
+       if (err && rollover) {
+               kfree(rollover);
                po->rollover = NULL;
        }
+       mutex_unlock(&fanout_mutex);
        return err;
 }
 
-static void fanout_release(struct sock *sk)
+/* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
+ * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
+ * It is the responsibility of the caller to call fanout_release_data() and
+ * free the returned packet_fanout (after synchronize_net())
+ */
+static struct packet_fanout *fanout_release(struct sock *sk)
 {
        struct packet_sock *po = pkt_sk(sk);
        struct packet_fanout *f;
 
+       mutex_lock(&fanout_mutex);
        f = po->fanout;
-       if (!f)
-               return;
+       if (f) {
+               po->fanout = NULL;
 
-       mutex_lock(&fanout_mutex);
-       po->fanout = NULL;
+               if (atomic_dec_and_test(&f->sk_ref))
+                       list_del(&f->list);
+               else
+                       f = NULL;
 
-       if (atomic_dec_and_test(&f->sk_ref)) {
-               list_del(&f->list);
-               dev_remove_pack(&f->prot_hook);
-               fanout_release_data(f);
-               kfree(f);
+               if (po->rollover)
+                       kfree_rcu(po->rollover, rcu);
        }
        mutex_unlock(&fanout_mutex);
 
-       if (po->rollover)
-               kfree_rcu(po->rollover, rcu);
+       return f;
 }
 
 static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
@@ -2907,6 +2920,7 @@ static int packet_release(struct socket *sock)
 {
        struct sock *sk = sock->sk;
        struct packet_sock *po;
+       struct packet_fanout *f;
        struct net *net;
        union tpacket_req_u req_u;
 
@@ -2946,9 +2960,14 @@ static int packet_release(struct socket *sock)
                packet_set_ring(sk, &req_u, 1, 1);
        }
 
-       fanout_release(sk);
+       f = fanout_release(sk);
 
        synchronize_net();
+
+       if (f) {
+               fanout_release_data(f);
+               kfree(f);
+       }
        /*
         *      Now the socket is dead. No more input will appear.
         */
@@ -3900,7 +3919,6 @@ static int packet_notifier(struct notifier_block *this,
                                }
                                if (msg == NETDEV_UNREGISTER) {
                                        packet_cached_dev_reset(po);
-                                       fanout_release(sk);
                                        po->ifindex = -1;
                                        if (po->prot_hook.dev)
                                                dev_put(po->prot_hook.dev);