tipc: redefine message acknowledge function

The function tipc_acknowledge() is a remnant from the obsolete native
API. Currently, it grabs port_lock, before building an acknowledge
message and sending it to the peer.

Since all access to socket members now is protected by the socket lock,
it has become unnecessary to grab port_lock here.

In this commit, we remove the usage of port_lock, simplify the
function, and move it to socket.c, renaming it to tipc_sk_send_ack().

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index a651058..686a11b 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1106,6 +1106,24 @@
 	return 0;
 }
 
+static void tipc_sk_send_ack(struct tipc_port *port, uint ack)
+{
+	struct sk_buff *buf = NULL;
+	struct tipc_msg *msg;
+	u32 peer_port = tipc_port_peerport(port);
+	u32 dnode = tipc_port_peernode(port);
+
+	if (!port->connected)
+		return;
+	buf = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0, dnode,
+			      tipc_own_addr, peer_port, port->ref, TIPC_OK);
+	if (!buf)
+		return;
+	msg = buf_msg(buf);
+	msg_set_msgcnt(msg, ack);
+	tipc_link_xmit(buf, dnode, msg_link_selector(msg));
+}
+
 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
 {
 	struct sock *sk = sock->sk;
@@ -1226,7 +1244,7 @@
 	if (likely(!(flags & MSG_PEEK))) {
 		if ((sock->state != SS_READY) &&
 		    (++tsk->rcv_unacked >= TIPC_CONNACK_INTV)) {
-			tipc_acknowledge(port->ref, tsk->rcv_unacked);
+			tipc_sk_send_ack(port, tsk->rcv_unacked);
 			tsk->rcv_unacked = 0;
 		}
 		advance_rx_queue(sk);
@@ -1337,7 +1355,7 @@
 	/* Consume received message (optional) */
 	if (likely(!(flags & MSG_PEEK))) {
 		if (unlikely(++tsk->rcv_unacked >= TIPC_CONNACK_INTV)) {
-			tipc_acknowledge(port->ref, tsk->rcv_unacked);
+			tipc_sk_send_ack(port, tsk->rcv_unacked);
 			tsk->rcv_unacked = 0;
 		}
 		advance_rx_queue(sk);