tipc: standardize sendmsg routine of connected socket

Standardize the behaviour of waiting for events in TIPC send_packet()
so that all variables of socket or port structures are protected within
socket lock, allowing the process of calling sendmsg() to be woken up
at appropriate time.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 3e019737e4b342d1efeae3ea5f00dbf333677f97..c4803101fbdfb91bdb48f917c6bc956c4f17f216 100644 (file)
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -695,6 +695,34 @@ exit:
        return res;
 }
 
+static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p)
+{
+       struct sock *sk = sock->sk;
+       struct tipc_port *tport = tipc_sk_port(sk);
+       DEFINE_WAIT(wait);
+       int done;
+
+       do {
+               int err = sock_error(sk);
+               if (err)
+                       return err;
+               if (sock->state == SS_DISCONNECTING)
+                       return -EPIPE;
+               else if (sock->state != SS_CONNECTED)
+                       return -ENOTCONN;
+               if (!*timeo_p)
+                       return -EAGAIN;
+               if (signal_pending(current))
+                       return sock_intr_errno(*timeo_p);
+
+               prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+               done = sk_wait_event(sk, timeo_p,
+                                    (!tport->congested || !tport->connected));
+               finish_wait(sk_sleep(sk), &wait);
+       } while (!done);
+       return 0;
+}
+
 /**
  * send_packet - send a connection-oriented message
  * @iocb: if NULL, indicates that socket lock is already held
@@ -712,8 +740,8 @@ static int send_packet(struct kiocb *iocb, struct socket *sock,
        struct sock *sk = sock->sk;
        struct tipc_port *tport = tipc_sk_port(sk);
        struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
-       long timeout_val;
-       int res;
+       int res = -EINVAL;
+       long timeo;
 
        /* Handle implied connection establishment */
        if (unlikely(dest))
@@ -725,30 +753,24 @@ static int send_packet(struct kiocb *iocb, struct socket *sock,
        if (iocb)
                lock_sock(sk);
 
-       timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
+       if (unlikely(sock->state != SS_CONNECTED)) {
+               if (sock->state == SS_DISCONNECTING)
+                       res = -EPIPE;
+               else
+                       res = -ENOTCONN;
+               goto exit;
+       }
 
+       timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
        do {
-               if (unlikely(sock->state != SS_CONNECTED)) {
-                       if (sock->state == SS_DISCONNECTING)
-                               res = -EPIPE;
-                       else
-                               res = -ENOTCONN;
-                       break;
-               }
-
                res = tipc_send(tport->ref, m->msg_iov, total_len);
                if (likely(res != -ELINKCONG))
                        break;
-               if (timeout_val <= 0L) {
-                       res = timeout_val ? timeout_val : -EWOULDBLOCK;
+               res = tipc_wait_for_sndpkt(sock, &timeo);
+               if (res)
                        break;
-               }
-               release_sock(sk);
-               timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk),
-                       (!tport->congested || !tport->connected), timeout_val);
-               lock_sock(sk);
        } while (1);
-
+exit:
        if (iocb)
                release_sock(sk);
        return res;