Re: [PATCH v2 10/12] l2tp: Add L2TP ethernet pseudowire support

[Eric Dumazet <eric.dumazet@gmail.com>]

Le lundi 29 mars 2010 à 10:57 +0100, James Chapman a écrit :

> +static struct l2tp_session *l2tp_eth_session_find_by_ifname(struct net *net, char *ifname)
> +{
> +	struct net_device *dev;
> +
> +	dev = dev_get_by_name(net, ifname);
> +	if (dev) {
> +		struct l2tp_eth *priv = netdev_priv(dev);
> +		return priv->session;
> +	}
> +
> +	return NULL;
> +}
> +

Not clear to me if  caller of l2tp_eth_session_find_by_ifname()
is able to do dev_put(dev);

l2tp_eth_create() ->


> +static int l2tp_eth_create(struct net *net, u32 tunnel_id, 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) {
> +		session = l2tp_eth_session_find_by_ifname(net, cfg->ifname);
> +		if (session) {
> +			rc = -EEXIST;
> +			goto out;
> +		}
> +		strlcpy(name, cfg->ifname, IFNAMSIZ);
> +	} else
> +		strcpy(name, L2TP_ETH_DEV_NAME);
> +
> +	session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
> +				      peer_session_id, cfg);
> +	if (!session) {
> +		rc = -ENOMEM;
> +		goto out;
> +	}
> +
> +	dev = alloc_netdev(sizeof(*priv), name, l2tp_eth_dev_setup);
> +	if (!dev) {
> +		rc = -ENOMEM;
> +		goto out_del_session;
> +	}
> +
> +	dev_net_set(dev, net);
> +	if (session->mtu == 0)
> +		session->mtu = dev->mtu - session->hdr_len;
> +	dev->mtu = session->mtu;
> +	dev->needed_headroom += session->hdr_len;
> +
> +	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;
> +	session->session_close = l2tp_eth_delete;
> +#ifdef CONFIG_PROC_FS
> +	session->show = l2tp_eth_show;
> +#endif
> +
> +	spriv = l2tp_session_priv(session);
> +	spriv->dev = dev;
> +
> +	rc = register_netdev(dev);
> +	if (rc < 0)
> +		goto out_del_dev;
> +
> +	/* Must be done after register_netdev() */
> +	strlcpy(session->ifname, dev->name, IFNAMSIZ);
> +
> +	dev_hold(dev);
> +	pn = l2tp_eth_pernet(dev_net(dev));
> +	write_lock(&pn->l2tp_eth_lock);
> +	list_add(&priv->list, &pn->l2tp_eth_dev_list);
> +	write_unlock(&pn->l2tp_eth_lock);
> +
> +	return 0;
> +
> +out_del_dev:
> +	free_netdev(dev);
> +out_del_session:
> +	l2tp_session_delete(session);

	I cant see the dev_put() here


> +out:
> +	return rc;
> +}