struct net_device *dev;
struct sock *tunnel_sock;
struct l2tp_session *session;
- struct list_head list;
};
/* via l2tp_session_priv() */
struct l2tp_eth_sess {
- struct net_device *dev;
-};
-
-/* per-net private data for this module */
-static unsigned int l2tp_eth_net_id;
-struct l2tp_eth_net {
- struct list_head l2tp_eth_dev_list;
- spinlock_t l2tp_eth_lock;
+ struct net_device __rcu *dev;
};
-static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
-{
- return net_generic(net, l2tp_eth_net_id);
-}
static int l2tp_eth_dev_init(struct net_device *dev)
{
static void l2tp_eth_dev_uninit(struct net_device *dev)
{
struct l2tp_eth *priv = netdev_priv(dev);
- struct l2tp_eth_net *pn = l2tp_eth_pernet(dev_net(dev));
+ struct l2tp_eth_sess *spriv;
- spin_lock(&pn->l2tp_eth_lock);
- list_del_init(&priv->list);
- spin_unlock(&pn->l2tp_eth_lock);
- dev_put(dev);
+ spriv = l2tp_session_priv(priv->session);
+ RCU_INIT_POINTER(spriv->dev, NULL);
+ /* No need for synchronize_net() here. We're called by
+ * unregister_netdev*(), which does the synchronisation for us.
+ */
}
static int l2tp_eth_dev_xmit(struct sk_buff *skb, struct net_device *dev)
static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
{
struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
- struct net_device *dev = spriv->dev;
+ struct net_device *dev;
if (session->debug & L2TP_MSG_DATA) {
unsigned int length;
printk("\n");
}
- if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
+ if (!pskb_may_pull(skb, ETH_HLEN))
goto error;
secpath_reset(skb);
skb_dst_drop(skb);
nf_reset(skb);
+ rcu_read_lock();
+ dev = rcu_dereference(spriv->dev);
+ if (!dev)
+ goto error_rcu;
+
if (dev_forward_skb(dev, skb) == NET_RX_SUCCESS) {
dev->stats.rx_packets++;
dev->stats.rx_bytes += data_len;
} else
dev->stats.rx_errors++;
+ rcu_read_unlock();
return;
+error_rcu:
+ rcu_read_unlock();
error:
dev->stats.rx_errors++;
kfree_skb(skb);
if (session) {
spriv = l2tp_session_priv(session);
- dev = spriv->dev;
+
+ rtnl_lock();
+ dev = rtnl_dereference(spriv->dev);
if (dev) {
- unregister_netdev(dev);
- spriv->dev = NULL;
+ unregister_netdevice(dev);
+ rtnl_unlock();
+ module_put(THIS_MODULE);
+ } else {
+ rtnl_unlock();
}
}
}
{
struct l2tp_session *session = arg;
struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
- struct net_device *dev = spriv->dev;
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = rcu_dereference(spriv->dev);
+ if (!dev) {
+ rcu_read_unlock();
+ return;
+ }
+ dev_hold(dev);
+ rcu_read_unlock();
seq_printf(m, " interface %s\n", dev->name);
+
+ dev_put(dev);
}
#endif
-static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
+static int l2tp_eth_create(struct net *net, struct l2tp_tunnel *tunnel,
+ u32 session_id, u32 peer_session_id,
+ struct l2tp_session_cfg *cfg)
{
struct net_device *dev;
char name[IFNAMSIZ];
- struct l2tp_tunnel *tunnel;
struct l2tp_session *session;
struct l2tp_eth *priv;
struct l2tp_eth_sess *spriv;
int rc;
- struct l2tp_eth_net *pn;
-
- tunnel = l2tp_tunnel_find(net, tunnel_id);
- if (!tunnel) {
- rc = -ENODEV;
- goto out;
- }
-
- session = l2tp_session_find(net, tunnel, session_id);
- if (session) {
- rc = -EEXIST;
- goto out;
- }
if (cfg->ifname) {
dev = dev_get_by_name(net, cfg->ifname);
if (dev) {
dev_put(dev);
rc = -EEXIST;
- goto out;
+ goto err;
}
strlcpy(name, cfg->ifname, IFNAMSIZ);
} else
session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
peer_session_id, cfg);
- if (!session) {
- rc = -ENOMEM;
- goto out;
+ if (IS_ERR(session)) {
+ rc = PTR_ERR(session);
+ goto err;
}
dev = alloc_netdev(sizeof(*priv), name, l2tp_eth_dev_setup);
if (!dev) {
rc = -ENOMEM;
- goto out_del_session;
+ goto err_sess;
}
dev_net_set(dev, net);
priv = netdev_priv(dev);
priv->dev = dev;
priv->session = session;
- INIT_LIST_HEAD(&priv->list);
priv->tunnel_sock = tunnel->sock;
session->recv_skb = l2tp_eth_dev_recv;
#endif
spriv = l2tp_session_priv(session);
- spriv->dev = dev;
- rc = register_netdev(dev);
- if (rc < 0)
- goto out_del_dev;
+ l2tp_session_inc_refcount(session);
- /* Must be done after register_netdev() */
- strlcpy(session->ifname, dev->name, IFNAMSIZ);
+ rtnl_lock();
- dev_hold(dev);
- pn = l2tp_eth_pernet(dev_net(dev));
- spin_lock(&pn->l2tp_eth_lock);
- list_add(&priv->list, &pn->l2tp_eth_dev_list);
- spin_unlock(&pn->l2tp_eth_lock);
+ /* Register both device and session while holding the rtnl lock. This
+ * ensures that l2tp_eth_delete() will see that there's a device to
+ * unregister, even if it happened to run before we assign spriv->dev.
+ */
+ rc = l2tp_session_register(session, tunnel);
+ if (rc < 0) {
+ rtnl_unlock();
+ goto err_sess_dev;
+ }
- return 0;
+ rc = register_netdevice(dev);
+ if (rc < 0) {
+ rtnl_unlock();
+ l2tp_session_delete(session);
+ l2tp_session_dec_refcount(session);
+ free_netdev(dev);
-out_del_dev:
- free_netdev(dev);
-out_del_session:
- l2tp_session_delete(session);
-out:
- return rc;
-}
+ return rc;
+ }
-static __net_init int l2tp_eth_init_net(struct net *net)
-{
- struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);
+ strlcpy(session->ifname, dev->name, IFNAMSIZ);
+ rcu_assign_pointer(spriv->dev, dev);
- INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
- spin_lock_init(&pn->l2tp_eth_lock);
+ rtnl_unlock();
+
+ l2tp_session_dec_refcount(session);
+
+ __module_get(THIS_MODULE);
return 0;
-}
-static struct pernet_operations l2tp_eth_net_ops = {
- .init = l2tp_eth_init_net,
- .id = &l2tp_eth_net_id,
- .size = sizeof(struct l2tp_eth_net),
-};
+err_sess_dev:
+ l2tp_session_dec_refcount(session);
+ free_netdev(dev);
+err_sess:
+ kfree(session);
+err:
+ return rc;
+}
static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
if (err)
- goto out;
-
- err = register_pernet_device(&l2tp_eth_net_ops);
- if (err)
- goto out_unreg;
+ goto err;
printk(KERN_INFO "L2TP ethernet pseudowire support (L2TPv3)\n");
return 0;
-out_unreg:
- l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
-out:
+err:
return err;
}
static void __exit l2tp_eth_exit(void)
{
- unregister_pernet_device(&l2tp_eth_net_ops);
l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
}
git.openpandora.org / pandora-kernel.git / blobdiff