[DLM] More othercon fixes

The last patch to clean out 'othercon' structures only fixed half the problem.
The attached addresses the other situations too, and fixes bz#238490

Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

fs/dlm/lowcomms.c

@@ -328,15 +328,24 @@ static void close_connection(struct connection *con, bool and_other)
 	if (con->othercon && and_other) {
 		/* Will only re-enter once. */
 		close_connection(con->othercon, false);
-		kmem_cache_free(con_cache, con->othercon);
-		con->othercon = NULL;
 	}
 	if (con->rx_page) {
 		__free_page(con->rx_page);
 		con->rx_page = NULL;
 	}
-	con->retries = 0;
-	mutex_unlock(&con->sock_mutex);
+
+	/* If we are an 'othercon' then NULL the pointer to us
+	   from the parent and tidy ourself up */
+	if (test_bit(CF_IS_OTHERCON, &con->flags)) {
+		struct connection *parent = __nodeid2con(con->nodeid, 0);
+		parent->othercon = NULL;
+		kmem_cache_free(con_cache, con);
+	}
+	else {
+		/* Parent connections get reused */
+		con->retries = 0;
+		mutex_unlock(&con->sock_mutex);
+	}
 }
 
 /* We only send shutdown messages to nodes that are not part of the cluster */
@@ -634,7 +643,7 @@ static int receive_from_sock(struct connection *con)
 
 out_close:
 	mutex_unlock(&con->sock_mutex);
-	if (ret != -EAGAIN && !test_bit(CF_IS_OTHERCON, &con->flags)) {
+	if (ret != -EAGAIN) {
 		close_connection(con, false);
 		/* Reconnect when there is something to send */
 	}
@@ -1125,8 +1134,6 @@ static int tcp_listen_for_all(void)
 
 	log_print("Using TCP for communications");
 
-	set_bit(CF_IS_OTHERCON, &con->flags);
-
 	sock = tcp_create_listen_sock(con, dlm_local_addr[0]);
 	if (sock) {
 		add_sock(sock, con);
@@ -1410,7 +1417,7 @@ void dlm_lowcomms_stop(void)
 	for (i = 0; i <= max_nodeid; i++) {
 		con = __nodeid2con(i, 0);
 		if (con) {
-			con->flags |= 0xFF;
+			con->flags |= 0x0F;
 			if (con->sock)
 				con->sock->sk->sk_user_data = NULL;
 		}
@@ -1426,8 +1433,6 @@ void dlm_lowcomms_stop(void)
 		con = __nodeid2con(i, 0);
 		if (con) {
 			close_connection(con, true);
-			if (con->othercon)
-				kmem_cache_free(con_cache, con->othercon);
 			kmem_cache_free(con_cache, con);
 		}
 	}