X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fipv4%2Ftcp.c;h=987b94403be55be814fb5245300236fb0b863558;hb=40b42f1ebf653cd72c32eb1a1a0b9fea2dfbfd7d;hp=cd3c7e95de9e07296de8583fdc5b3df73aa45cdf;hpb=8a2e21038df74c4401f422346b9371a959c21438;p=linux-2.6

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index cd3c7e95de..987b94403b 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1064,7 +1064,11 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
 					break;
 			}
 			used = recv_actor(desc, skb, offset, len);
-			if (used <= len) {
+			if (used < 0) {
+				if (!copied)
+					copied = used;
+				break;
+			} else if (used <= len) {
 				seq += used;
 				copied += used;
 				offset += used;
@@ -1086,7 +1090,7 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
 	tcp_rcv_space_adjust(sk);
 
 	/* Clean up data we have read: This will do ACK frames. */
-	if (copied)
+	if (copied > 0)
 		tcp_cleanup_rbuf(sk, copied);
 	return copied;
 }
@@ -1112,6 +1116,7 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	long timeo;
 	struct task_struct *user_recv = NULL;
 	int copied_early = 0;
+	struct sk_buff *skb;
 
 	lock_sock(sk);
 
@@ -1138,16 +1143,26 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 #ifdef CONFIG_NET_DMA
 	tp->ucopy.dma_chan = NULL;
 	preempt_disable();
-	if ((len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) &&
-	    !sysctl_tcp_low_latency && __get_cpu_var(softnet_data).net_dma) {
-		preempt_enable_no_resched();
-		tp->ucopy.pinned_list = dma_pin_iovec_pages(msg->msg_iov, len);
-	} else
-		preempt_enable_no_resched();
+	skb = skb_peek_tail(&sk->sk_receive_queue);
+	{
+		int available = 0;
+
+		if (skb)
+			available = TCP_SKB_CB(skb)->seq + skb->len - (*seq);
+		if ((available < target) &&
+		    (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) &&
+		    !sysctl_tcp_low_latency &&
+		    __get_cpu_var(softnet_data).net_dma) {
+			preempt_enable_no_resched();
+			tp->ucopy.pinned_list =
+					dma_pin_iovec_pages(msg->msg_iov, len);
+		} else {
+			preempt_enable_no_resched();
+		}
+	}
 #endif
 
 	do {
-		struct sk_buff *skb;
 		u32 offset;
 
 		/* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
@@ -1435,7 +1450,6 @@ skip_copy:
 
 #ifdef CONFIG_NET_DMA
 	if (tp->ucopy.dma_chan) {
-		struct sk_buff *skb;
 		dma_cookie_t done, used;
 
 		dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);