Merge branch 'tipc_net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Paul Gortmaker says:

====================
The most interesting thing here, at least from a user perspective,
is the broadcast link fix -- where there was a corner case where
two endpoints could get in a state where they disagree on where
to start Rx and ack of broadcast packets.

There is also the poll/wait changes which could also impact
end users for certain use cases - the fixes there also better
align tipc with the rest of the networking code.

The rest largely falls into routine cleanup category, by getting
rid of some unused routines, some Kconfig clutter, etc.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 49 insertions, 9 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index fd5f042dbff4..1a720c86e80a 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -62,6 +62,8 @@ struct tipc_sock {
 static int backlog_rcv(struct sock *sk, struct sk_buff *skb);
 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf);
 static void wakeupdispatch(struct tipc_port *tport);
+static void tipc_data_ready(struct sock *sk, int len);
+static void tipc_write_space(struct sock *sk);
 
 static const struct proto_ops packet_ops;
 static const struct proto_ops stream_ops;
@@ -221,6 +223,8 @@ static int tipc_create(struct net *net, struct socket *sock, int protocol,
 	sock_init_data(sock, sk);
 	sk->sk_backlog_rcv = backlog_rcv;
 	sk->sk_rcvbuf = TIPC_FLOW_CONTROL_WIN * 2 * TIPC_MAX_USER_MSG_SIZE * 2;
+	sk->sk_data_ready = tipc_data_ready;
+	sk->sk_write_space = tipc_write_space;
 	tipc_sk(sk)->p = tp_ptr;
 	tipc_sk(sk)->conn_timeout = CONN_TIMEOUT_DEFAULT;
 
@@ -408,7 +412,7 @@ static int get_name(struct socket *sock, struct sockaddr *uaddr,
  * socket state		flags set
  * ------------		---------
  * unconnected		no read flags
- *			no write flags
+ *			POLLOUT if port is not congested
  *
  * connecting		POLLIN/POLLRDNORM if ACK/NACK in rx queue
  *			no write flags
@@ -435,9 +439,13 @@ static unsigned int poll(struct file *file, struct socket *sock,
 	struct sock *sk = sock->sk;
 	u32 mask = 0;
 
-	poll_wait(file, sk_sleep(sk), wait);
+	sock_poll_wait(file, sk_sleep(sk), wait);
 
 	switch ((int)sock->state) {
+	case SS_UNCONNECTED:
+		if (!tipc_sk_port(sk)->congested)
+			mask |= POLLOUT;
+		break;
 	case SS_READY:
 	case SS_CONNECTED:
 		if (!tipc_sk_port(sk)->congested)
@@ -1126,6 +1134,39 @@ exit:
 }
 
 /**
+ * tipc_write_space - wake up thread if port congestion is released
+ * @sk: socket
+ */
+static void tipc_write_space(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
+						POLLWRNORM | POLLWRBAND);
+	rcu_read_unlock();
+}
+
+/**
+ * tipc_data_ready - wake up threads to indicate messages have been received
+ * @sk: socket
+ * @len: the length of messages
+ */
+static void tipc_data_ready(struct sock *sk, int len)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
+						POLLRDNORM | POLLRDBAND);
+	rcu_read_unlock();
+}
+
+/**
  * rx_queue_full - determine if receive queue can accept another message
  * @msg: message to be added to queue
  * @queue_size: current size of queue
@@ -1222,8 +1263,7 @@ static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
 		tipc_disconnect_port(tipc_sk_port(sk));
 	}
 
-	if (waitqueue_active(sk_sleep(sk)))
-		wake_up_interruptible(sk_sleep(sk));
+	sk->sk_data_ready(sk, 0);
 	return TIPC_OK;
 }
 
@@ -1290,8 +1330,7 @@ static void wakeupdispatch(struct tipc_port *tport)
 {
 	struct sock *sk = (struct sock *)tport->usr_handle;
 
-	if (waitqueue_active(sk_sleep(sk)))
-		wake_up_interruptible(sk_sleep(sk));
+	sk->sk_write_space(sk);
 }
 
 /**
@@ -1556,10 +1595,11 @@ restart:
 
 	case SS_DISCONNECTING:
 
-		/* Discard any unreceived messages; wake up sleeping tasks */
+		/* Discard any unreceived messages */
 		discard_rx_queue(sk);
-		if (waitqueue_active(sk_sleep(sk)))
-			wake_up_interruptible(sk_sleep(sk));
+
+		/* Wake up anyone sleeping in poll */
+		sk->sk_state_change(sk);
 		res = 0;
 		break;