diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 17b3f70fbbc3..c618fbf7d173 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -288,6 +288,7 @@ struct sk_buff { __u8 pkt_type:3, fclone:2, ipvs_property:1, + peeked:1, nf_trace:1; __be16 protocol; @@ -1538,6 +1539,8 @@ static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) skb = skb->prev) +extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, + int *peeked, int *err); extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock, int *err); extern unsigned int datagram_poll(struct file *file, struct socket *sock, diff --git a/net/core/datagram.c b/net/core/datagram.c index fbd6c76436d0..2d733131d7ce 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -115,10 +115,10 @@ out_noerr: } /** - * skb_recv_datagram - Receive a datagram skbuff + * __skb_recv_datagram - Receive a datagram skbuff * @sk: socket * @flags: MSG_ flags - * @noblock: blocking operation? + * @peeked: returns non-zero if this packet has been seen before * @err: error code returned * * Get a datagram skbuff, understands the peeking, nonblocking wakeups @@ -143,8 +143,8 @@ out_noerr: * quite explicitly by POSIX 1003.1g, don't change them without having * the standard around please. */ -struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, - int noblock, int *err) +struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, + int *peeked, int *err) { struct sk_buff *skb; long timeo; @@ -156,7 +156,7 @@ struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, if (error) goto no_packet; - timeo = sock_rcvtimeo(sk, noblock); + timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); do { /* Again only user level code calls this function, so nothing @@ -165,18 +165,19 @@ struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, * Look at current nfs client by the way... * However, this function was corrent in any case. 8) */ - if (flags & MSG_PEEK) { - unsigned long cpu_flags; + unsigned long cpu_flags; - spin_lock_irqsave(&sk->sk_receive_queue.lock, - cpu_flags); - skb = skb_peek(&sk->sk_receive_queue); - if (skb) + spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags); + skb = skb_peek(&sk->sk_receive_queue); + if (skb) { + *peeked = skb->peeked; + if (flags & MSG_PEEK) { + skb->peeked = 1; atomic_inc(&skb->users); - spin_unlock_irqrestore(&sk->sk_receive_queue.lock, - cpu_flags); - } else - skb = skb_dequeue(&sk->sk_receive_queue); + } else + __skb_unlink(skb, &sk->sk_receive_queue); + } + spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags); if (skb) return skb; @@ -194,6 +195,16 @@ no_packet: *err = error; return NULL; } +EXPORT_SYMBOL(__skb_recv_datagram); + +struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, + int noblock, int *err) +{ + int peeked; + + return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), + &peeked, err); +} void skb_free_datagram(struct sock *sk, struct sk_buff *skb) { diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 78cfcb4a1b3f..9ed6393c65d9 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -827,6 +827,7 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; struct sk_buff *skb; unsigned int ulen, copied; + int peeked; int err; int is_udplite = IS_UDPLITE(sk); @@ -840,7 +841,8 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, return ip_recv_error(sk, msg, len); try_again: - skb = skb_recv_datagram(sk, flags, noblock, &err); + skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), + &peeked, &err); if (!skb) goto out; @@ -875,7 +877,8 @@ try_again: if (err) goto out_free; - UDP_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite); + if (!peeked) + UDP_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite); sock_recv_timestamp(msg, sk, skb); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 36bdcd2e1b52..fa640765385e 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -123,6 +123,7 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; unsigned int ulen, copied; + int peeked; int err; int is_udplite = IS_UDPLITE(sk); @@ -133,7 +134,8 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, return ipv6_recv_error(sk, msg, len); try_again: - skb = skb_recv_datagram(sk, flags, noblock, &err); + skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), + &peeked, &err); if (!skb) goto out; @@ -166,7 +168,8 @@ try_again: if (err) goto out_free; - UDP6_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite); + if (!peeked) + UDP6_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite); sock_recv_timestamp(msg, sk, skb);