1 files changed, 18 insertions, 8 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 450f44bb2c8e..987b94403be5 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1116,6 +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);
 
@@ -1142,16 +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. */
@@ -1439,7 +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);