1 files changed, 51 insertions, 31 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 613daf8c1ff7..ddbe981ab516 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -136,12 +136,6 @@ static ctl_table sunrpc_table[] = {
 #endif
 
 /*
- * How many times to try sending a request on a socket before waiting
- * for the socket buffer to clear.
- */
-#define XS_SENDMSG_RETRY        (10U)
-
-/*
  * Time out for an RPC UDP socket connect.  UDP socket connects are
  * synchronous, but we set a timeout anyway in case of resource
  * exhaustion on the local host.
@@ -516,6 +510,14 @@ out:
         return sent;
 }
 
+static void xs_nospace_callback(struct rpc_task *task)
+{
+        struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
+
+        transport->inet->sk_write_pending--;
+        clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
+}
+
 /**
  * xs_nospace - place task on wait queue if transmit was incomplete
  * @task: task to put to sleep
@@ -531,20 +533,27 @@ static void xs_nospace(struct rpc_task *task)
                         task->tk_pid, req->rq_slen - req->rq_bytes_sent,
                         req->rq_slen);
 
-        if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
-                /* Protect against races with write_space */
-                spin_lock_bh(&xprt->transport_lock);
-
-                /* Don't race with disconnect */
-                if (!xprt_connected(xprt))
-                        task->tk_status = -ENOTCONN;
-                else if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
-                        xprt_wait_for_buffer_space(task);
+        /* Protect against races with write_space */
+        spin_lock_bh(&xprt->transport_lock);
+
+        /* Don't race with disconnect */
+        if (xprt_connected(xprt)) {
+                if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
+                        /*
+                         * Notify TCP that we're limited by the application
+                         * window size
+                         */
+                        set_bit(SOCK_NOSPACE, &transport->sock->flags);
+                        transport->inet->sk_write_pending++;
+                        /* ...and wait for more buffer space */
+                        xprt_wait_for_buffer_space(task, xs_nospace_callback);
+                }
+        } else {
+                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
+                task->tk_status = -ENOTCONN;
+        }
 
-                spin_unlock_bh(&xprt->transport_lock);
-        } else
-                /* Keep holding the socket if it is blocked */
-                rpc_delay(task, HZ>>4);
+        spin_unlock_bh(&xprt->transport_lock);
 }
 
 /**
@@ -588,19 +597,20 @@ static int xs_udp_send_request(struct rpc_task *task)
         }
 
         switch (status) {
+        case -EAGAIN:
+                xs_nospace(task);
+                break;
         case -ENETUNREACH:
         case -EPIPE:
         case -ECONNREFUSED:
                 /* When the server has died, an ICMP port unreachable message
                  * prompts ECONNREFUSED. */
-                break;
-        case -EAGAIN:
-                xs_nospace(task);
+                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
                 break;
         default:
+                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
                         -status);
-                break;
         }
 
         return status;
@@ -650,7 +660,6 @@ static int xs_tcp_send_request(struct rpc_task *task)
         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
         struct xdr_buf *xdr = &req->rq_snd_buf;
         int status;
-        unsigned int retry = 0;
 
         xs_encode_tcp_record_marker(&req->rq_snd_buf);
 
@@ -681,9 +690,10 @@ static int xs_tcp_send_request(struct rpc_task *task)
                         return 0;
                 }
 
+                if (status != 0)
+                        continue;
                 status = -EAGAIN;
-                if (retry++ > XS_SENDMSG_RETRY)
-                        break;
+                break;
         }
 
         switch (status) {
@@ -695,12 +705,13 @@ static int xs_tcp_send_request(struct rpc_task *task)
         case -ENOTCONN:
         case -EPIPE:
                 status = -ENOTCONN;
+                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
                 break;
         default:
                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
                         -status);
+                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
                 xs_tcp_shutdown(xprt);
-                break;
         }
 
         return status;
@@ -1073,6 +1084,7 @@ static void xs_tcp_data_ready(struct sock *sk, int bytes)
 {
         struct rpc_xprt *xprt;
         read_descriptor_t rd_desc;
+        int read;
 
         dprintk("RPC:       xs_tcp_data_ready...\n");
 
@@ -1084,8 +1096,10 @@ static void xs_tcp_data_ready(struct sock *sk, int bytes)
 
         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
         rd_desc.arg.data = xprt;
-        rd_desc.count = 65536;
-        tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
+        do {
+                rd_desc.count = 65536;
+                read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
+        } while (read > 0);
 out:
         read_unlock(&sk->sk_callback_lock);
 }
@@ -1128,6 +1142,7 @@ static void xs_tcp_state_change(struct sock *sk)
                 break;
         case TCP_FIN_WAIT1:
                 /* The client initiated a shutdown of the socket */
+                xprt->connect_cookie++;
                 xprt->reestablish_timeout = 0;
                 set_bit(XPRT_CLOSING, &xprt->state);
                 smp_mb__before_clear_bit();
@@ -1140,6 +1155,7 @@ static void xs_tcp_state_change(struct sock *sk)
                 set_bit(XPRT_CLOSING, &xprt->state);
                 xprt_force_disconnect(xprt);
         case TCP_SYN_SENT:
+                xprt->connect_cookie++;
         case TCP_CLOSING:
                 /*
                  * If the server closed down the connection, make sure that
@@ -1186,9 +1202,11 @@ static void xs_udp_write_space(struct sock *sk)
 
                 if (unlikely(!(sock = sk->sk_socket)))
                         goto out;
+                clear_bit(SOCK_NOSPACE, &sock->flags);
+
                 if (unlikely(!(xprt = xprt_from_sock(sk))))
                         goto out;
-                if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
+                if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
                         goto out;
 
                 xprt_write_space(xprt);
@@ -1219,9 +1237,11 @@ static void xs_tcp_write_space(struct sock *sk)
 
                 if (unlikely(!(sock = sk->sk_socket)))
                         goto out;
+                clear_bit(SOCK_NOSPACE, &sock->flags);
+
                 if (unlikely(!(xprt = xprt_from_sock(sk))))
                         goto out;
-                if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
+                if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
                         goto out;
 
                 xprt_write_space(xprt);