1 files changed, 136 insertions, 48 deletions

diff --git a/net/rds/threads.c b/net/rds/threads.c
index 65eaefcab241..1f424cbfcbb4 100644
--- a/net/rds/threads.c
+++ b/net/rds/threads.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006 Oracle.  All rights reserved.
+ * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -71,25 +71,35 @@
 struct workqueue_struct *rds_wq;
 EXPORT_SYMBOL_GPL(rds_wq);
 
-void rds_connect_complete(struct rds_connection *conn)
+void rds_connect_path_complete(struct rds_conn_path *cp, int curr)
 {
-	if (!rds_conn_transition(conn, RDS_CONN_CONNECTING, RDS_CONN_UP)) {
+	if (!rds_conn_path_transition(cp, curr, RDS_CONN_UP)) {
 		printk(KERN_WARNING "%s: Cannot transition to state UP, "
 				"current state is %d\n",
 				__func__,
-				atomic_read(&conn->c_state));
-		atomic_set(&conn->c_state, RDS_CONN_ERROR);
-		queue_work(rds_wq, &conn->c_down_w);
+				atomic_read(&cp->cp_state));
+		rds_conn_path_drop(cp, false);
 		return;
 	}
 
-	rdsdebug("conn %p for %pI4 to %pI4 complete\n",
-	  conn, &conn->c_laddr, &conn->c_faddr);
+	rdsdebug("conn %p for %pI6c to %pI6c complete\n",
+		 cp->cp_conn, &cp->cp_conn->c_laddr, &cp->cp_conn->c_faddr);
+
+	cp->cp_reconnect_jiffies = 0;
+	set_bit(0, &cp->cp_conn->c_map_queued);
+	rcu_read_lock();
+	if (!rds_destroy_pending(cp->cp_conn)) {
+		queue_delayed_work(rds_wq, &cp->cp_send_w, 0);
+		queue_delayed_work(rds_wq, &cp->cp_recv_w, 0);
+	}
+	rcu_read_unlock();
+	cp->cp_conn->c_proposed_version = RDS_PROTOCOL_VERSION;
+}
+EXPORT_SYMBOL_GPL(rds_connect_path_complete);
 
-	conn->c_reconnect_jiffies = 0;
-	set_bit(0, &conn->c_map_queued);
-	queue_delayed_work(rds_wq, &conn->c_send_w, 0);
-	queue_delayed_work(rds_wq, &conn->c_recv_w, 0);
+void rds_connect_complete(struct rds_connection *conn)
+{
+	rds_connect_path_complete(&conn->c_path[0], RDS_CONN_CONNECTING);
 }
 EXPORT_SYMBOL_GPL(rds_connect_complete);
 
@@ -111,68 +121,94 @@ EXPORT_SYMBOL_GPL(rds_connect_complete);
  * We should *always* start with a random backoff; otherwise a broken connection
  * will always take several iterations to be re-established.
  */
-void rds_queue_reconnect(struct rds_connection *conn)
+void rds_queue_reconnect(struct rds_conn_path *cp)
 {
 	unsigned long rand;
+	struct rds_connection *conn = cp->cp_conn;
 
-	rdsdebug("conn %p for %pI4 to %pI4 reconnect jiffies %lu\n",
-	  conn, &conn->c_laddr, &conn->c_faddr,
-	  conn->c_reconnect_jiffies);
+	rdsdebug("conn %p for %pI6c to %pI6c reconnect jiffies %lu\n",
+		 conn, &conn->c_laddr, &conn->c_faddr,
+		 cp->cp_reconnect_jiffies);
 
-	set_bit(RDS_RECONNECT_PENDING, &conn->c_flags);
-	if (conn->c_reconnect_jiffies == 0) {
-		conn->c_reconnect_jiffies = rds_sysctl_reconnect_min_jiffies;
-		queue_delayed_work(rds_wq, &conn->c_conn_w, 0);
+	/* let peer with smaller addr initiate reconnect, to avoid duels */
+	if (conn->c_trans->t_type == RDS_TRANS_TCP &&
+	    rds_addr_cmp(&conn->c_laddr, &conn->c_faddr) >= 0)
+		return;
+
+	set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags);
+	if (cp->cp_reconnect_jiffies == 0) {
+		cp->cp_reconnect_jiffies = rds_sysctl_reconnect_min_jiffies;
+		rcu_read_lock();
+		if (!rds_destroy_pending(cp->cp_conn))
+			queue_delayed_work(rds_wq, &cp->cp_conn_w, 0);
+		rcu_read_unlock();
 		return;
 	}
 
 	get_random_bytes(&rand, sizeof(rand));
-	rdsdebug("%lu delay %lu ceil conn %p for %pI4 -> %pI4\n",
-		 rand % conn->c_reconnect_jiffies, conn->c_reconnect_jiffies,
+	rdsdebug("%lu delay %lu ceil conn %p for %pI6c -> %pI6c\n",
+		 rand % cp->cp_reconnect_jiffies, cp->cp_reconnect_jiffies,
 		 conn, &conn->c_laddr, &conn->c_faddr);
-	queue_delayed_work(rds_wq, &conn->c_conn_w,
-			   rand % conn->c_reconnect_jiffies);
+	rcu_read_lock();
+	if (!rds_destroy_pending(cp->cp_conn))
+		queue_delayed_work(rds_wq, &cp->cp_conn_w,
+				   rand % cp->cp_reconnect_jiffies);
+	rcu_read_unlock();
 
-	conn->c_reconnect_jiffies = min(conn->c_reconnect_jiffies * 2,
+	cp->cp_reconnect_jiffies = min(cp->cp_reconnect_jiffies * 2,
 					rds_sysctl_reconnect_max_jiffies);
 }
 
 void rds_connect_worker(struct work_struct *work)
 {
-	struct rds_connection *conn = container_of(work, struct rds_connection, c_conn_w.work);
+	struct rds_conn_path *cp = container_of(work,
+						struct rds_conn_path,
+						cp_conn_w.work);
+	struct rds_connection *conn = cp->cp_conn;
 	int ret;
 
-	clear_bit(RDS_RECONNECT_PENDING, &conn->c_flags);
-	if (rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
-		ret = conn->c_trans->conn_connect(conn);
-		rdsdebug("conn %p for %pI4 to %pI4 dispatched, ret %d\n",
-			conn, &conn->c_laddr, &conn->c_faddr, ret);
+	if (cp->cp_index > 0 &&
+	    rds_addr_cmp(&cp->cp_conn->c_laddr, &cp->cp_conn->c_faddr) >= 0)
+		return;
+	clear_bit(RDS_RECONNECT_PENDING, &cp->cp_flags);
+	ret = rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_CONNECTING);
+	if (ret) {
+		ret = conn->c_trans->conn_path_connect(cp);
+		rdsdebug("conn %p for %pI6c to %pI6c dispatched, ret %d\n",
+			 conn, &conn->c_laddr, &conn->c_faddr, ret);
 
 		if (ret) {
-			if (rds_conn_transition(conn, RDS_CONN_CONNECTING, RDS_CONN_DOWN))
-				rds_queue_reconnect(conn);
+			if (rds_conn_path_transition(cp,
+						     RDS_CONN_CONNECTING,
+						     RDS_CONN_DOWN))
+				rds_queue_reconnect(cp);
 			else
-				rds_conn_error(conn, "RDS: connect failed\n");
+				rds_conn_path_error(cp, "connect failed\n");
 		}
 	}
 }
 
 void rds_send_worker(struct work_struct *work)
 {
-	struct rds_connection *conn = container_of(work, struct rds_connection, c_send_w.work);
+	struct rds_conn_path *cp = container_of(work,
+						struct rds_conn_path,
+						cp_send_w.work);
 	int ret;
 
-	if (rds_conn_state(conn) == RDS_CONN_UP) {
-		ret = rds_send_xmit(conn);
-		rdsdebug("conn %p ret %d\n", conn, ret);
+	if (rds_conn_path_state(cp) == RDS_CONN_UP) {
+		clear_bit(RDS_LL_SEND_FULL, &cp->cp_flags);
+		ret = rds_send_xmit(cp);
+		cond_resched();
+		rdsdebug("conn %p ret %d\n", cp->cp_conn, ret);
 		switch (ret) {
 		case -EAGAIN:
 			rds_stats_inc(s_send_immediate_retry);
-			queue_delayed_work(rds_wq, &conn->c_send_w, 0);
+			queue_delayed_work(rds_wq, &cp->cp_send_w, 0);
 			break;
 		case -ENOMEM:
 			rds_stats_inc(s_send_delayed_retry);
-			queue_delayed_work(rds_wq, &conn->c_send_w, 2);
+			queue_delayed_work(rds_wq, &cp->cp_send_w, 2);
+			break;
 		default:
 			break;
 		}
@@ -181,20 +217,23 @@ void rds_send_worker(struct work_struct *work)
 
 void rds_recv_worker(struct work_struct *work)
 {
-	struct rds_connection *conn = container_of(work, struct rds_connection, c_recv_w.work);
+	struct rds_conn_path *cp = container_of(work,
+						struct rds_conn_path,
+						cp_recv_w.work);
 	int ret;
 
-	if (rds_conn_state(conn) == RDS_CONN_UP) {
-		ret = conn->c_trans->recv(conn);
-		rdsdebug("conn %p ret %d\n", conn, ret);
+	if (rds_conn_path_state(cp) == RDS_CONN_UP) {
+		ret = cp->cp_conn->c_trans->recv_path(cp);
+		rdsdebug("conn %p ret %d\n", cp->cp_conn, ret);
 		switch (ret) {
 		case -EAGAIN:
 			rds_stats_inc(s_recv_immediate_retry);
-			queue_delayed_work(rds_wq, &conn->c_recv_w, 0);
+			queue_delayed_work(rds_wq, &cp->cp_recv_w, 0);
 			break;
 		case -ENOMEM:
 			rds_stats_inc(s_recv_delayed_retry);
-			queue_delayed_work(rds_wq, &conn->c_recv_w, 2);
+			queue_delayed_work(rds_wq, &cp->cp_recv_w, 2);
+			break;
 		default:
 			break;
 		}
@@ -203,9 +242,11 @@ void rds_recv_worker(struct work_struct *work)
 
 void rds_shutdown_worker(struct work_struct *work)
 {
-	struct rds_connection *conn = container_of(work, struct rds_connection, c_down_w);
+	struct rds_conn_path *cp = container_of(work,
+						struct rds_conn_path,
+						cp_down_w);
 
-	rds_conn_shutdown(conn);
+	rds_conn_shutdown(cp);
 }
 
 void rds_threads_exit(void)
@@ -221,3 +262,50 @@ int rds_threads_init(void)
 
 	return 0;
 }
+
+/* Compare two IPv6 addresses.  Return 0 if the two addresses are equal.
+ * Return 1 if the first is greater.  Return -1 if the second is greater.
+ */
+int rds_addr_cmp(const struct in6_addr *addr1,
+		 const struct in6_addr *addr2)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const __be64 *a1, *a2;
+	u64 x, y;
+
+	a1 = (__be64 *)addr1;
+	a2 = (__be64 *)addr2;
+
+	if (*a1 != *a2) {
+		if (be64_to_cpu(*a1) < be64_to_cpu(*a2))
+			return -1;
+		else
+			return 1;
+	} else {
+		x = be64_to_cpu(*++a1);
+		y = be64_to_cpu(*++a2);
+		if (x < y)
+			return -1;
+		else if (x > y)
+			return 1;
+		else
+			return 0;
+	}
+#else
+	u32 a, b;
+	int i;
+
+	for (i = 0; i < 4; i++) {
+		if (addr1->s6_addr32[i] != addr2->s6_addr32[i]) {
+			a = ntohl(addr1->s6_addr32[i]);
+			b = ntohl(addr2->s6_addr32[i]);
+			if (a < b)
+				return -1;
+			else if (a > b)
+				return 1;
+		}
+	}
+	return 0;
+#endif
+}
+EXPORT_SYMBOL_GPL(rds_addr_cmp);