+int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+ struct sk_buff *skb;
+ int amount;
+
+ switch (cmd) {
+ case SIOCOUTQ:
+ amount = sk_wmem_alloc_get(sk);
+ break;
+ case SIOCINQ:
+ spin_lock_bh(&sk->sk_receive_queue.lock);
+ skb = skb_peek(&sk->sk_receive_queue);
+ amount = skb ? skb->len : 0;
+ spin_unlock_bh(&sk->sk_receive_queue.lock);
+ break;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+
+ return put_user(amount, (int __user *)arg);
+}
+EXPORT_SYMBOL(l2tp_ioctl);
+