Merge branch 'rds-tcp-fixes'

Sowmini Varadhan says:

====================
rds: tcp: fixes

Patch1 is a bug fix for correct reconnect when a connection
is restarted. Patch 2 accelerates cleanup by setting linger
to 1 and sending a RST to the peer.
====================

Signed-off-by: David S. Miller <[e-mail]>

net/rds/connection.c

···
 		 "%pI4\n", conn, &conn->c_laddr,
 		 &conn->c_faddr);
 
+	conn->c_destroy_in_prog = 1;
 	/* Ensure conn will not be scheduled for reconnect */
 	spin_lock_irq(&rds_conn_lock);
 	hlist_del_init_rcu(&conn->c_hash_node);

net/rds/rds.h

···
 	__be32			c_faddr;
 	unsigned int		c_loopback:1,
 				c_ping_triggered:1,
-				c_pad_to_32:30;
+				c_destroy_in_prog:1,
+				c_pad_to_32:29;
 	int			c_npaths;
 	struct rds_connection	*c_passive;
 	struct rds_transport	*c_trans;
···
 			 is_acked_func is_acked);
 void rds_send_path_drop_acked(struct rds_conn_path *cp, u64 ack,
 			      is_acked_func is_acked);
+void rds_send_ping(struct rds_connection *conn, int cp_index);
 int rds_send_pong(struct rds_conn_path *cp, __be16 dport);
 
 /* rdma.c */

net/rds/recv.c

···
 	}
 	/* if RDS_EXTHDR_NPATHS was not found, default to a single-path */
 	conn->c_npaths = max_t(int, conn->c_npaths, 1);
+	conn->c_ping_triggered = 0;
 	rds_conn_peer_gen_update(conn, new_peer_gen_num);
 }
 
···
  *    called after reception of the probe-pong on all mprds_paths.
  *    Otherwise (sender of probe-ping is not the smaller ip addr): just call
  *    rds_conn_path_connect_if_down on the hashed path. (see rule 4)
- * 4. when cp_index > 0, rds_connect_worker must only trigger
- *    a connection if laddr < faddr.
+ * 4. rds_connect_worker must only trigger a connection if laddr < faddr.
  * 5. sender may end up queuing the packet on the cp. will get sent out later.
  *    when connection is completed.
  */
···
 
 	if (conn->c_npaths > 1 &&
 	    IS_CANONICAL(conn->c_laddr, conn->c_faddr)) {
-		for (i = 1; i < conn->c_npaths; i++) {
+		for (i = 0; i < conn->c_npaths; i++) {
 			cp = &conn->c_path[i];
 			rds_conn_path_connect_if_down(cp);
 		}

net/rds/send.c

···
 	return ret;
 }
 
-static void rds_send_ping(struct rds_connection *conn);
-
 static int rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn)
 {
 	int hash;
···
 	else
 		hash = RDS_MPATH_HASH(rs, conn->c_npaths);
 	if (conn->c_npaths == 0 && hash != 0) {
-		rds_send_ping(conn);
+		rds_send_ping(conn, 0);
 
 		if (conn->c_npaths == 0) {
 			wait_event_interruptible(conn->c_hs_waitq,
···
 	return rds_send_probe(cp, 0, dport, 0);
 }
 
-static void
-rds_send_ping(struct rds_connection *conn)
+void
+rds_send_ping(struct rds_connection *conn, int cp_index)
 {
 	unsigned long flags;
-	struct rds_conn_path *cp = &conn->c_path[0];
+	struct rds_conn_path *cp = &conn->c_path[cp_index];
 
 	spin_lock_irqsave(&cp->cp_lock, flags);
 	if (conn->c_ping_triggered) {
···
 	}
 	conn->c_ping_triggered = 1;
 	spin_unlock_irqrestore(&cp->cp_lock, flags);
-	rds_send_probe(&conn->c_path[0], cpu_to_be16(RDS_FLAG_PROBE_PORT),
-		       0, 0);
+	rds_send_probe(cp, cpu_to_be16(RDS_FLAG_PROBE_PORT), 0, 0);
 }
+EXPORT_SYMBOL_GPL(rds_send_ping);

net/rds/tcp.h

···
 int rds_tcp_accept_one(struct socket *sock);
 int rds_tcp_keepalive(struct socket *sock);
 void *rds_tcp_listen_sock_def_readable(struct net *net);
+void rds_tcp_set_linger(struct socket *sock);
 
 /* tcp_recv.c */
 int rds_tcp_recv_init(void);

net/rds/tcp_connect.c

···
 		 cp->cp_conn, tc, sock);
 
 	if (sock) {
+		if (cp->cp_conn->c_destroy_in_prog)
+			rds_tcp_set_linger(sock);
 		sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN);
 		lock_sock(sock->sk);
 		rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */

net/rds/tcp_listen.c

···
 	return NULL;
 }
 
-static void rds_tcp_set_linger(struct socket *sock)
+void rds_tcp_set_linger(struct socket *sock)
 {
 	struct linger no_linger = {
 		.l_onoff = 1,
···
 	}
 	new_sock = NULL;
 	ret = 0;
+	if (conn->c_npaths == 0)
+		rds_send_ping(cp->cp_conn, cp->cp_index);
 	goto out;
 rst_nsk:
 	/* reset the newly returned accept sock and bail.