1 files changed, 46 insertions, 21 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 5901010fad55..0f8caf64caa3 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -265,6 +265,7 @@
 #include <linux/err.h>
 #include <linux/crypto.h>
 #include <linux/time.h>
+#include <linux/slab.h>
 
 #include <net/icmp.h>
 #include <net/tcp.h>
@@ -429,7 +430,7 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
                 if (tp->urg_seq == tp->copied_seq &&
                     !sock_flag(sk, SOCK_URGINLINE) &&
                     tp->urg_data)
-                        target--;
+                        target++;
 
                 /* Potential race condition. If read of tp below will
                  * escape above sk->sk_state, we can be illegally awaken
@@ -1254,6 +1255,39 @@ static void tcp_prequeue_process(struct sock *sk)
         tp->ucopy.memory = 0;
 }
 
+#ifdef CONFIG_NET_DMA
+static void tcp_service_net_dma(struct sock *sk, bool wait)
+{
+        dma_cookie_t done, used;
+        dma_cookie_t last_issued;
+        struct tcp_sock *tp = tcp_sk(sk);
+
+        if (!tp->ucopy.dma_chan)
+                return;
+
+        last_issued = tp->ucopy.dma_cookie;
+        dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
+
+        do {
+                if (dma_async_memcpy_complete(tp->ucopy.dma_chan,
+                                              last_issued, &done,
+                                              &used) == DMA_SUCCESS) {
+                        /* Safe to free early-copied skbs now */
+                        __skb_queue_purge(&sk->sk_async_wait_queue);
+                        break;
+                } else {
+                        struct sk_buff *skb;
+                        while ((skb = skb_peek(&sk->sk_async_wait_queue)) &&
+                               (dma_async_is_complete(skb->dma_cookie, done,
+                                                      used) == DMA_SUCCESS)) {
+                                __skb_dequeue(&sk->sk_async_wait_queue);
+                                kfree_skb(skb);
+                        }
+                }
+        } while (wait);
+}
+#endif
+
 static inline struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
 {
         struct sk_buff *skb;
@@ -1335,6 +1369,7 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
                 sk_eat_skb(sk, skb, 0);
                 if (!desc->count)
                         break;
+                tp->copied_seq = seq;
         }
         tp->copied_seq = seq;
 
@@ -1546,6 +1581,10 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                         /* __ Set realtime policy in scheduler __ */
                 }
 
+#ifdef CONFIG_NET_DMA
+                if (tp->ucopy.dma_chan)
+                        dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
+#endif
                 if (copied >= target) {
                         /* Do not sleep, just process backlog. */
                         release_sock(sk);
@@ -1554,6 +1593,7 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                         sk_wait_data(sk, &timeo);
 
 #ifdef CONFIG_NET_DMA
+                tcp_service_net_dma(sk, false);  /* Don't block */
                 tp->ucopy.wakeup = 0;
 #endif
 
@@ -1633,6 +1673,9 @@ do_prequeue:
                                                 copied = -EFAULT;
                                         break;
                                 }
+
+                                dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
+
                                 if ((offset + used) == skb->len)
                                         copied_early = 1;
 
@@ -1702,27 +1745,9 @@ skip_copy:
         }
 
 #ifdef CONFIG_NET_DMA
-        if (tp->ucopy.dma_chan) {
-                dma_cookie_t done, used;
-
-                dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
-
-                while (dma_async_memcpy_complete(tp->ucopy.dma_chan,
-                                                 tp->ucopy.dma_cookie, &done,
-                                                 &used) == DMA_IN_PROGRESS) {
-                        /* do partial cleanup of sk_async_wait_queue */
-                        while ((skb = skb_peek(&sk->sk_async_wait_queue)) &&
-                               (dma_async_is_complete(skb->dma_cookie, done,
-                                                      used) == DMA_SUCCESS)) {
-                                __skb_dequeue(&sk->sk_async_wait_queue);
-                                kfree_skb(skb);
-                        }
-                }
+        tcp_service_net_dma(sk, true);  /* Wait for queue to drain */
+        tp->ucopy.dma_chan = NULL;
 
-                /* Safe to free early-copied skbs now */
-                __skb_queue_purge(&sk->sk_async_wait_queue);
-                tp->ucopy.dma_chan = NULL;
-        }
         if (tp->ucopy.pinned_list) {
                 dma_unpin_iovec_pages(tp->ucopy.pinned_list);
                 tp->ucopy.pinned_list = NULL;