diff options
Diffstat (limited to 'net/core/datagram.c')
-rw-r--r-- | net/core/datagram.c | 72 |
1 files changed, 44 insertions, 28 deletions
diff --git a/net/core/datagram.c b/net/core/datagram.c index b7de71f..9482037 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -165,6 +165,7 @@ done: * __skb_try_recv_datagram - Receive a datagram skbuff * @sk: socket * @flags: MSG_ flags + * @destructor: invoked under the receive lock on successful dequeue * @peeked: returns non-zero if this packet has been seen before * @off: an offset in bytes to peek skb from. Returns an offset * within an skb where data actually starts @@ -197,6 +198,8 @@ done: * the standard around please. */ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags, + void (*destructor)(struct sock *sk, + struct sk_buff *skb), int *peeked, int *off, int *err, struct sk_buff **last) { @@ -211,6 +214,7 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags, if (error) goto no_packet; + *peeked = 0; do { /* Again only user level code calls this function, so nothing * interrupt level will suddenly eat the receive_queue. @@ -224,26 +228,28 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags, spin_lock_irqsave(&queue->lock, cpu_flags); skb_queue_walk(queue, skb) { *last = skb; - *peeked = skb->peeked; if (flags & MSG_PEEK) { if (_off >= skb->len && (skb->len || _off || skb->peeked)) { _off -= skb->len; continue; } - - skb = skb_set_peeked(skb); - error = PTR_ERR(skb); - if (IS_ERR(skb)) { - spin_unlock_irqrestore(&queue->lock, - cpu_flags); - goto no_packet; + if (!skb->len) { + skb = skb_set_peeked(skb); + if (IS_ERR(skb)) { + error = PTR_ERR(skb); + spin_unlock_irqrestore(&queue->lock, + cpu_flags); + goto no_packet; + } } - + *peeked = 1; atomic_inc(&skb->users); - } else + } else { __skb_unlink(skb, queue); - + if (destructor) + destructor(sk, skb); + } spin_unlock_irqrestore(&queue->lock, cpu_flags); *off = _off; return skb; @@ -262,6 +268,8 @@ no_packet: EXPORT_SYMBOL(__skb_try_recv_datagram); struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned int flags, + void (*destructor)(struct sock *sk, + struct sk_buff *skb), int *peeked, int *off, int *err) { struct sk_buff *skb, *last; @@ -270,8 +278,8 @@ struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned int flags, timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); do { - skb = __skb_try_recv_datagram(sk, flags, peeked, off, err, - &last); + skb = __skb_try_recv_datagram(sk, flags, destructor, peeked, + off, err, &last); if (skb) return skb; @@ -290,7 +298,7 @@ struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned int flags, int peeked, off = 0; return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), - &peeked, &off, err); + NULL, &peeked, &off, err); } EXPORT_SYMBOL(skb_recv_datagram); @@ -323,6 +331,27 @@ void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len) } EXPORT_SYMBOL(__skb_free_datagram_locked); +int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb, + unsigned int flags) +{ + int err = 0; + + if (flags & MSG_PEEK) { + err = -ENOENT; + spin_lock_bh(&sk->sk_receive_queue.lock); + if (skb == skb_peek(&sk->sk_receive_queue)) { + __skb_unlink(skb, &sk->sk_receive_queue); + atomic_dec(&skb->users); + err = 0; + } + spin_unlock_bh(&sk->sk_receive_queue.lock); + } + + atomic_inc(&sk->sk_drops); + return err; +} +EXPORT_SYMBOL(__sk_queue_drop_skb); + /** * skb_kill_datagram - Free a datagram skbuff forcibly * @sk: socket @@ -346,23 +375,10 @@ EXPORT_SYMBOL(__skb_free_datagram_locked); int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags) { - int err = 0; - - if (flags & MSG_PEEK) { - err = -ENOENT; - spin_lock_bh(&sk->sk_receive_queue.lock); - if (skb == skb_peek(&sk->sk_receive_queue)) { - __skb_unlink(skb, &sk->sk_receive_queue); - atomic_dec(&skb->users); - err = 0; - } - spin_unlock_bh(&sk->sk_receive_queue.lock); - } + int err = __sk_queue_drop_skb(sk, skb, flags); kfree_skb(skb); - atomic_inc(&sk->sk_drops); sk_mem_reclaim_partial(sk); - return err; } EXPORT_SYMBOL(skb_kill_datagram); |