100e0f34cSAndy Grover /* 200e0f34cSAndy Grover * Copyright (c) 2006 Oracle. All rights reserved. 300e0f34cSAndy Grover * 400e0f34cSAndy Grover * This software is available to you under a choice of one of two 500e0f34cSAndy Grover * licenses. You may choose to be licensed under the terms of the GNU 600e0f34cSAndy Grover * General Public License (GPL) Version 2, available from the file 700e0f34cSAndy Grover * COPYING in the main directory of this source tree, or the 800e0f34cSAndy Grover * OpenIB.org BSD license below: 900e0f34cSAndy Grover * 1000e0f34cSAndy Grover * Redistribution and use in source and binary forms, with or 1100e0f34cSAndy Grover * without modification, are permitted provided that the following 1200e0f34cSAndy Grover * conditions are met: 1300e0f34cSAndy Grover * 1400e0f34cSAndy Grover * - Redistributions of source code must retain the above 1500e0f34cSAndy Grover * copyright notice, this list of conditions and the following 1600e0f34cSAndy Grover * disclaimer. 1700e0f34cSAndy Grover * 1800e0f34cSAndy Grover * - Redistributions in binary form must reproduce the above 1900e0f34cSAndy Grover * copyright notice, this list of conditions and the following 2000e0f34cSAndy Grover * disclaimer in the documentation and/or other materials 2100e0f34cSAndy Grover * provided with the distribution. 2200e0f34cSAndy Grover * 2300e0f34cSAndy Grover * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 2400e0f34cSAndy Grover * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 2500e0f34cSAndy Grover * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 2600e0f34cSAndy Grover * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 2700e0f34cSAndy Grover * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 2800e0f34cSAndy Grover * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 2900e0f34cSAndy Grover * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 3000e0f34cSAndy Grover * SOFTWARE. 3100e0f34cSAndy Grover * 3200e0f34cSAndy Grover */ 3300e0f34cSAndy Grover #include <linux/kernel.h> 3400e0f34cSAndy Grover #include <linux/list.h> 355a0e3ad6STejun Heo #include <linux/slab.h> 36bc3b2d7fSPaul Gortmaker #include <linux/export.h> 3700e0f34cSAndy Grover #include <net/inet_hashtables.h> 3800e0f34cSAndy Grover 3900e0f34cSAndy Grover #include "rds.h" 4000e0f34cSAndy Grover #include "loop.h" 4100e0f34cSAndy Grover 4200e0f34cSAndy Grover #define RDS_CONNECTION_HASH_BITS 12 4300e0f34cSAndy Grover #define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS) 4400e0f34cSAndy Grover #define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1) 4500e0f34cSAndy Grover 4600e0f34cSAndy Grover /* converting this to RCU is a chore for another day.. */ 4700e0f34cSAndy Grover static DEFINE_SPINLOCK(rds_conn_lock); 4800e0f34cSAndy Grover static unsigned long rds_conn_count; 4900e0f34cSAndy Grover static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES]; 5000e0f34cSAndy Grover static struct kmem_cache *rds_conn_slab; 5100e0f34cSAndy Grover 5200e0f34cSAndy Grover static struct hlist_head *rds_conn_bucket(__be32 laddr, __be32 faddr) 5300e0f34cSAndy Grover { 541bbdceefSHannes Frederic Sowa static u32 rds_hash_secret __read_mostly; 551bbdceefSHannes Frederic Sowa 561bbdceefSHannes Frederic Sowa unsigned long hash; 571bbdceefSHannes Frederic Sowa 581bbdceefSHannes Frederic Sowa net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret)); 591bbdceefSHannes Frederic Sowa 6000e0f34cSAndy Grover /* Pass NULL, don't need struct net for hash */ 611bbdceefSHannes Frederic Sowa hash = __inet_ehashfn(be32_to_cpu(laddr), 0, 6265cd8033SHannes Frederic Sowa be32_to_cpu(faddr), 0, 631bbdceefSHannes Frederic Sowa rds_hash_secret); 6400e0f34cSAndy Grover return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK]; 6500e0f34cSAndy Grover } 6600e0f34cSAndy Grover 6700e0f34cSAndy Grover #define rds_conn_info_set(var, test, suffix) do { \ 6800e0f34cSAndy Grover if (test) \ 6900e0f34cSAndy Grover var |= RDS_INFO_CONNECTION_FLAG_##suffix; \ 7000e0f34cSAndy Grover } while (0) 7100e0f34cSAndy Grover 72bcf50ef2SChris Mason /* rcu read lock must be held or the connection spinlock */ 738f384c01SSowmini Varadhan static struct rds_connection *rds_conn_lookup(struct net *net, 748f384c01SSowmini Varadhan struct hlist_head *head, 7500e0f34cSAndy Grover __be32 laddr, __be32 faddr, 7600e0f34cSAndy Grover struct rds_transport *trans) 7700e0f34cSAndy Grover { 7800e0f34cSAndy Grover struct rds_connection *conn, *ret = NULL; 7900e0f34cSAndy Grover 80b67bfe0dSSasha Levin hlist_for_each_entry_rcu(conn, head, c_hash_node) { 8100e0f34cSAndy Grover if (conn->c_faddr == faddr && conn->c_laddr == laddr && 828f384c01SSowmini Varadhan conn->c_trans == trans && net == rds_conn_net(conn)) { 8300e0f34cSAndy Grover ret = conn; 8400e0f34cSAndy Grover break; 8500e0f34cSAndy Grover } 8600e0f34cSAndy Grover } 8700e0f34cSAndy Grover rdsdebug("returning conn %p for %pI4 -> %pI4\n", ret, 8800e0f34cSAndy Grover &laddr, &faddr); 8900e0f34cSAndy Grover return ret; 9000e0f34cSAndy Grover } 9100e0f34cSAndy Grover 9200e0f34cSAndy Grover /* 9300e0f34cSAndy Grover * This is called by transports as they're bringing down a connection. 9400e0f34cSAndy Grover * It clears partial message state so that the transport can start sending 9500e0f34cSAndy Grover * and receiving over this connection again in the future. It is up to 9600e0f34cSAndy Grover * the transport to have serialized this call with its send and recv. 9700e0f34cSAndy Grover */ 98d769ef81SSowmini Varadhan static void rds_conn_path_reset(struct rds_conn_path *cp) 9900e0f34cSAndy Grover { 100d769ef81SSowmini Varadhan struct rds_connection *conn = cp->cp_conn; 101d769ef81SSowmini Varadhan 10200e0f34cSAndy Grover rdsdebug("connection %pI4 to %pI4 reset\n", 10300e0f34cSAndy Grover &conn->c_laddr, &conn->c_faddr); 10400e0f34cSAndy Grover 10500e0f34cSAndy Grover rds_stats_inc(s_conn_reset); 106d769ef81SSowmini Varadhan rds_send_path_reset(cp); 107d769ef81SSowmini Varadhan cp->cp_flags = 0; 10800e0f34cSAndy Grover 10900e0f34cSAndy Grover /* Do not clear next_rx_seq here, else we cannot distinguish 11000e0f34cSAndy Grover * retransmitted packets from new packets, and will hand all 11100e0f34cSAndy Grover * of them to the application. That is not consistent with the 11200e0f34cSAndy Grover * reliability guarantees of RDS. */ 11300e0f34cSAndy Grover } 11400e0f34cSAndy Grover 1151c5113cfSSowmini Varadhan static void __rds_conn_path_init(struct rds_connection *conn, 1161c5113cfSSowmini Varadhan struct rds_conn_path *cp, bool is_outgoing) 1171c5113cfSSowmini Varadhan { 1181c5113cfSSowmini Varadhan spin_lock_init(&cp->cp_lock); 1191c5113cfSSowmini Varadhan cp->cp_next_tx_seq = 1; 1201c5113cfSSowmini Varadhan init_waitqueue_head(&cp->cp_waitq); 1211c5113cfSSowmini Varadhan INIT_LIST_HEAD(&cp->cp_send_queue); 1221c5113cfSSowmini Varadhan INIT_LIST_HEAD(&cp->cp_retrans); 1231c5113cfSSowmini Varadhan 1241c5113cfSSowmini Varadhan cp->cp_conn = conn; 1251c5113cfSSowmini Varadhan atomic_set(&cp->cp_state, RDS_CONN_DOWN); 1261c5113cfSSowmini Varadhan cp->cp_send_gen = 0; 1271c5113cfSSowmini Varadhan cp->cp_reconnect_jiffies = 0; 1281c5113cfSSowmini Varadhan INIT_DELAYED_WORK(&cp->cp_send_w, rds_send_worker); 1291c5113cfSSowmini Varadhan INIT_DELAYED_WORK(&cp->cp_recv_w, rds_recv_worker); 1301c5113cfSSowmini Varadhan INIT_DELAYED_WORK(&cp->cp_conn_w, rds_connect_worker); 1311c5113cfSSowmini Varadhan INIT_WORK(&cp->cp_down_w, rds_shutdown_worker); 1321c5113cfSSowmini Varadhan mutex_init(&cp->cp_cm_lock); 1331c5113cfSSowmini Varadhan cp->cp_flags = 0; 1341c5113cfSSowmini Varadhan } 1351c5113cfSSowmini Varadhan 13600e0f34cSAndy Grover /* 13700e0f34cSAndy Grover * There is only every one 'conn' for a given pair of addresses in the 13800e0f34cSAndy Grover * system at a time. They contain messages to be retransmitted and so 13900e0f34cSAndy Grover * span the lifetime of the actual underlying transport connections. 14000e0f34cSAndy Grover * 14100e0f34cSAndy Grover * For now they are not garbage collected once they're created. They 14200e0f34cSAndy Grover * are torn down as the module is removed, if ever. 14300e0f34cSAndy Grover */ 144d5a8ac28SSowmini Varadhan static struct rds_connection *__rds_conn_create(struct net *net, 145d5a8ac28SSowmini Varadhan __be32 laddr, __be32 faddr, 14600e0f34cSAndy Grover struct rds_transport *trans, gfp_t gfp, 14700e0f34cSAndy Grover int is_outgoing) 14800e0f34cSAndy Grover { 149cb24405eSAndy Grover struct rds_connection *conn, *parent = NULL; 15000e0f34cSAndy Grover struct hlist_head *head = rds_conn_bucket(laddr, faddr); 1515adb5bc6SZach Brown struct rds_transport *loop_trans; 15200e0f34cSAndy Grover unsigned long flags; 1535916e2c1SSowmini Varadhan int ret, i; 15400e0f34cSAndy Grover 155bcf50ef2SChris Mason rcu_read_lock(); 1568f384c01SSowmini Varadhan conn = rds_conn_lookup(net, head, laddr, faddr, trans); 157f64f9e71SJoe Perches if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport && 1581789b2c0SSowmini Varadhan laddr == faddr && !is_outgoing) { 15900e0f34cSAndy Grover /* This is a looped back IB connection, and we're 16000e0f34cSAndy Grover * called by the code handling the incoming connect. 16100e0f34cSAndy Grover * We need a second connection object into which we 16200e0f34cSAndy Grover * can stick the other QP. */ 16300e0f34cSAndy Grover parent = conn; 16400e0f34cSAndy Grover conn = parent->c_passive; 16500e0f34cSAndy Grover } 166bcf50ef2SChris Mason rcu_read_unlock(); 16700e0f34cSAndy Grover if (conn) 16800e0f34cSAndy Grover goto out; 16900e0f34cSAndy Grover 17005a178ecSWei Yongjun conn = kmem_cache_zalloc(rds_conn_slab, gfp); 1718690bfa1SAndy Grover if (!conn) { 17200e0f34cSAndy Grover conn = ERR_PTR(-ENOMEM); 17300e0f34cSAndy Grover goto out; 17400e0f34cSAndy Grover } 17500e0f34cSAndy Grover 17600e0f34cSAndy Grover INIT_HLIST_NODE(&conn->c_hash_node); 17700e0f34cSAndy Grover conn->c_laddr = laddr; 17800e0f34cSAndy Grover conn->c_faddr = faddr; 17900e0f34cSAndy Grover 1801c5113cfSSowmini Varadhan rds_conn_net_set(conn, net); 18100e0f34cSAndy Grover 18200e0f34cSAndy Grover ret = rds_cong_get_maps(conn); 18300e0f34cSAndy Grover if (ret) { 18400e0f34cSAndy Grover kmem_cache_free(rds_conn_slab, conn); 18500e0f34cSAndy Grover conn = ERR_PTR(ret); 18600e0f34cSAndy Grover goto out; 18700e0f34cSAndy Grover } 18800e0f34cSAndy Grover 18900e0f34cSAndy Grover /* 19000e0f34cSAndy Grover * This is where a connection becomes loopback. If *any* RDS sockets 19100e0f34cSAndy Grover * can bind to the destination address then we'd rather the messages 19200e0f34cSAndy Grover * flow through loopback rather than either transport. 19300e0f34cSAndy Grover */ 194d5a8ac28SSowmini Varadhan loop_trans = rds_trans_get_preferred(net, faddr); 1955adb5bc6SZach Brown if (loop_trans) { 1965adb5bc6SZach Brown rds_trans_put(loop_trans); 19700e0f34cSAndy Grover conn->c_loopback = 1; 19800e0f34cSAndy Grover if (is_outgoing && trans->t_prefer_loopback) { 19900e0f34cSAndy Grover /* "outgoing" connection - and the transport 20000e0f34cSAndy Grover * says it wants the connection handled by the 20100e0f34cSAndy Grover * loopback transport. This is what TCP does. 20200e0f34cSAndy Grover */ 20300e0f34cSAndy Grover trans = &rds_loop_transport; 20400e0f34cSAndy Grover } 20500e0f34cSAndy Grover } 20600e0f34cSAndy Grover 20700e0f34cSAndy Grover conn->c_trans = trans; 20800e0f34cSAndy Grover 2095916e2c1SSowmini Varadhan init_waitqueue_head(&conn->c_hs_waitq); 2105916e2c1SSowmini Varadhan for (i = 0; i < RDS_MPATH_WORKERS; i++) { 2115916e2c1SSowmini Varadhan __rds_conn_path_init(conn, &conn->c_path[i], 2125916e2c1SSowmini Varadhan is_outgoing); 2135916e2c1SSowmini Varadhan conn->c_path[i].cp_index = i; 2145916e2c1SSowmini Varadhan } 21500e0f34cSAndy Grover ret = trans->conn_alloc(conn, gfp); 21600e0f34cSAndy Grover if (ret) { 21700e0f34cSAndy Grover kmem_cache_free(rds_conn_slab, conn); 21800e0f34cSAndy Grover conn = ERR_PTR(ret); 21900e0f34cSAndy Grover goto out; 22000e0f34cSAndy Grover } 22100e0f34cSAndy Grover 22200e0f34cSAndy Grover rdsdebug("allocated conn %p for %pI4 -> %pI4 over %s %s\n", 22300e0f34cSAndy Grover conn, &laddr, &faddr, 22400e0f34cSAndy Grover trans->t_name ? trans->t_name : "[unknown]", 22500e0f34cSAndy Grover is_outgoing ? "(outgoing)" : ""); 22600e0f34cSAndy Grover 227cb24405eSAndy Grover /* 228cb24405eSAndy Grover * Since we ran without holding the conn lock, someone could 229cb24405eSAndy Grover * have created the same conn (either normal or passive) in the 230cb24405eSAndy Grover * interim. We check while holding the lock. If we won, we complete 231cb24405eSAndy Grover * init and return our conn. If we lost, we rollback and return the 232cb24405eSAndy Grover * other one. 233cb24405eSAndy Grover */ 23400e0f34cSAndy Grover spin_lock_irqsave(&rds_conn_lock, flags); 235cb24405eSAndy Grover if (parent) { 236cb24405eSAndy Grover /* Creating passive conn */ 237cb24405eSAndy Grover if (parent->c_passive) { 2381c5113cfSSowmini Varadhan trans->conn_free(conn->c_path[0].cp_transport_data); 23900e0f34cSAndy Grover kmem_cache_free(rds_conn_slab, conn); 240cb24405eSAndy Grover conn = parent->c_passive; 24100e0f34cSAndy Grover } else { 242cb24405eSAndy Grover parent->c_passive = conn; 24300e0f34cSAndy Grover rds_cong_add_conn(conn); 24400e0f34cSAndy Grover rds_conn_count++; 24500e0f34cSAndy Grover } 246cb24405eSAndy Grover } else { 247cb24405eSAndy Grover /* Creating normal conn */ 248cb24405eSAndy Grover struct rds_connection *found; 24900e0f34cSAndy Grover 2508f384c01SSowmini Varadhan found = rds_conn_lookup(net, head, laddr, faddr, trans); 251cb24405eSAndy Grover if (found) { 2521c5113cfSSowmini Varadhan struct rds_conn_path *cp; 2531c5113cfSSowmini Varadhan int i; 2541c5113cfSSowmini Varadhan 2551c5113cfSSowmini Varadhan for (i = 0; i < RDS_MPATH_WORKERS; i++) { 2561c5113cfSSowmini Varadhan cp = &conn->c_path[i]; 25702105b2cSSowmini Varadhan /* The ->conn_alloc invocation may have 25802105b2cSSowmini Varadhan * allocated resource for all paths, so all 25902105b2cSSowmini Varadhan * of them may have to be freed here. 26002105b2cSSowmini Varadhan */ 26102105b2cSSowmini Varadhan if (cp->cp_transport_data) 2621c5113cfSSowmini Varadhan trans->conn_free(cp->cp_transport_data); 2631c5113cfSSowmini Varadhan } 264cb24405eSAndy Grover kmem_cache_free(rds_conn_slab, conn); 265cb24405eSAndy Grover conn = found; 266cb24405eSAndy Grover } else { 267905dd418SSowmini Varadhan conn->c_my_gen_num = rds_gen_num; 268905dd418SSowmini Varadhan conn->c_peer_gen_num = 0; 269bcf50ef2SChris Mason hlist_add_head_rcu(&conn->c_hash_node, head); 270cb24405eSAndy Grover rds_cong_add_conn(conn); 271cb24405eSAndy Grover rds_conn_count++; 272cb24405eSAndy Grover } 273cb24405eSAndy Grover } 27400e0f34cSAndy Grover spin_unlock_irqrestore(&rds_conn_lock, flags); 27500e0f34cSAndy Grover 27600e0f34cSAndy Grover out: 27700e0f34cSAndy Grover return conn; 27800e0f34cSAndy Grover } 27900e0f34cSAndy Grover 280d5a8ac28SSowmini Varadhan struct rds_connection *rds_conn_create(struct net *net, 281d5a8ac28SSowmini Varadhan __be32 laddr, __be32 faddr, 28200e0f34cSAndy Grover struct rds_transport *trans, gfp_t gfp) 28300e0f34cSAndy Grover { 284d5a8ac28SSowmini Varadhan return __rds_conn_create(net, laddr, faddr, trans, gfp, 0); 28500e0f34cSAndy Grover } 286616b757aSAndy Grover EXPORT_SYMBOL_GPL(rds_conn_create); 28700e0f34cSAndy Grover 288d5a8ac28SSowmini Varadhan struct rds_connection *rds_conn_create_outgoing(struct net *net, 289d5a8ac28SSowmini Varadhan __be32 laddr, __be32 faddr, 29000e0f34cSAndy Grover struct rds_transport *trans, gfp_t gfp) 29100e0f34cSAndy Grover { 292d5a8ac28SSowmini Varadhan return __rds_conn_create(net, laddr, faddr, trans, gfp, 1); 29300e0f34cSAndy Grover } 294616b757aSAndy Grover EXPORT_SYMBOL_GPL(rds_conn_create_outgoing); 29500e0f34cSAndy Grover 296d769ef81SSowmini Varadhan void rds_conn_shutdown(struct rds_conn_path *cp) 2972dc39357SAndy Grover { 298d769ef81SSowmini Varadhan struct rds_connection *conn = cp->cp_conn; 299d769ef81SSowmini Varadhan 3002dc39357SAndy Grover /* shut it down unless it's down already */ 301d769ef81SSowmini Varadhan if (!rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_DOWN)) { 3022dc39357SAndy Grover /* 3032dc39357SAndy Grover * Quiesce the connection mgmt handlers before we start tearing 3042dc39357SAndy Grover * things down. We don't hold the mutex for the entire 3052dc39357SAndy Grover * duration of the shutdown operation, else we may be 3062dc39357SAndy Grover * deadlocking with the CM handler. Instead, the CM event 3072dc39357SAndy Grover * handler is supposed to check for state DISCONNECTING 3082dc39357SAndy Grover */ 309d769ef81SSowmini Varadhan mutex_lock(&cp->cp_cm_lock); 310d769ef81SSowmini Varadhan if (!rds_conn_path_transition(cp, RDS_CONN_UP, 311d769ef81SSowmini Varadhan RDS_CONN_DISCONNECTING) && 312d769ef81SSowmini Varadhan !rds_conn_path_transition(cp, RDS_CONN_ERROR, 313d769ef81SSowmini Varadhan RDS_CONN_DISCONNECTING)) { 314d769ef81SSowmini Varadhan rds_conn_path_error(cp, 315d769ef81SSowmini Varadhan "shutdown called in state %d\n", 316d769ef81SSowmini Varadhan atomic_read(&cp->cp_state)); 317d769ef81SSowmini Varadhan mutex_unlock(&cp->cp_cm_lock); 3182dc39357SAndy Grover return; 3192dc39357SAndy Grover } 320d769ef81SSowmini Varadhan mutex_unlock(&cp->cp_cm_lock); 3212dc39357SAndy Grover 322d769ef81SSowmini Varadhan wait_event(cp->cp_waitq, 323d769ef81SSowmini Varadhan !test_bit(RDS_IN_XMIT, &cp->cp_flags)); 324d769ef81SSowmini Varadhan wait_event(cp->cp_waitq, 325d769ef81SSowmini Varadhan !test_bit(RDS_RECV_REFILL, &cp->cp_flags)); 3267e3f2952SChris Mason 327d769ef81SSowmini Varadhan conn->c_trans->conn_path_shutdown(cp); 328d769ef81SSowmini Varadhan rds_conn_path_reset(cp); 3292dc39357SAndy Grover 330d769ef81SSowmini Varadhan if (!rds_conn_path_transition(cp, RDS_CONN_DISCONNECTING, 331e97656d0SSowmini Varadhan RDS_CONN_DOWN) && 332e97656d0SSowmini Varadhan !rds_conn_path_transition(cp, RDS_CONN_ERROR, 333d769ef81SSowmini Varadhan RDS_CONN_DOWN)) { 3342dc39357SAndy Grover /* This can happen - eg when we're in the middle of tearing 3352dc39357SAndy Grover * down the connection, and someone unloads the rds module. 336e97656d0SSowmini Varadhan * Quite reproducible with loopback connections. 3372dc39357SAndy Grover * Mostly harmless. 338e97656d0SSowmini Varadhan * 339e97656d0SSowmini Varadhan * Note that this also happens with rds-tcp because 340e97656d0SSowmini Varadhan * we could have triggered rds_conn_path_drop in irq 341e97656d0SSowmini Varadhan * mode from rds_tcp_state change on the receipt of 342e97656d0SSowmini Varadhan * a FIN, thus we need to recheck for RDS_CONN_ERROR 343e97656d0SSowmini Varadhan * here. 3442dc39357SAndy Grover */ 345d769ef81SSowmini Varadhan rds_conn_path_error(cp, "%s: failed to transition " 346d769ef81SSowmini Varadhan "to state DOWN, current state " 347d769ef81SSowmini Varadhan "is %d\n", __func__, 348d769ef81SSowmini Varadhan atomic_read(&cp->cp_state)); 3492dc39357SAndy Grover return; 3502dc39357SAndy Grover } 3512dc39357SAndy Grover } 3522dc39357SAndy Grover 3532dc39357SAndy Grover /* Then reconnect if it's still live. 3542dc39357SAndy Grover * The passive side of an IB loopback connection is never added 3552dc39357SAndy Grover * to the conn hash, so we never trigger a reconnect on this 3562dc39357SAndy Grover * conn - the reconnect is always triggered by the active peer. */ 357d769ef81SSowmini Varadhan cancel_delayed_work_sync(&cp->cp_conn_w); 358bcf50ef2SChris Mason rcu_read_lock(); 359bcf50ef2SChris Mason if (!hlist_unhashed(&conn->c_hash_node)) { 360bcf50ef2SChris Mason rcu_read_unlock(); 361d769ef81SSowmini Varadhan rds_queue_reconnect(cp); 362bcf50ef2SChris Mason } else { 363bcf50ef2SChris Mason rcu_read_unlock(); 364bcf50ef2SChris Mason } 3652dc39357SAndy Grover } 3662dc39357SAndy Grover 3673ecc5693SSowmini Varadhan /* destroy a single rds_conn_path. rds_conn_destroy() iterates over 3683ecc5693SSowmini Varadhan * all paths using rds_conn_path_destroy() 3693ecc5693SSowmini Varadhan */ 3703ecc5693SSowmini Varadhan static void rds_conn_path_destroy(struct rds_conn_path *cp) 3713ecc5693SSowmini Varadhan { 3723ecc5693SSowmini Varadhan struct rds_message *rm, *rtmp; 3733ecc5693SSowmini Varadhan 37402105b2cSSowmini Varadhan if (!cp->cp_transport_data) 37502105b2cSSowmini Varadhan return; 37602105b2cSSowmini Varadhan 3773ecc5693SSowmini Varadhan /* make sure lingering queued work won't try to ref the conn */ 3783ecc5693SSowmini Varadhan cancel_delayed_work_sync(&cp->cp_send_w); 3793ecc5693SSowmini Varadhan cancel_delayed_work_sync(&cp->cp_recv_w); 3803ecc5693SSowmini Varadhan 381*aed20a53SSowmini Varadhan rds_conn_path_drop(cp, true); 382*aed20a53SSowmini Varadhan flush_work(&cp->cp_down_w); 383*aed20a53SSowmini Varadhan 3843ecc5693SSowmini Varadhan /* tear down queued messages */ 3853ecc5693SSowmini Varadhan list_for_each_entry_safe(rm, rtmp, 3863ecc5693SSowmini Varadhan &cp->cp_send_queue, 3873ecc5693SSowmini Varadhan m_conn_item) { 3883ecc5693SSowmini Varadhan list_del_init(&rm->m_conn_item); 3893ecc5693SSowmini Varadhan BUG_ON(!list_empty(&rm->m_sock_item)); 3903ecc5693SSowmini Varadhan rds_message_put(rm); 3913ecc5693SSowmini Varadhan } 3923ecc5693SSowmini Varadhan if (cp->cp_xmit_rm) 3933ecc5693SSowmini Varadhan rds_message_put(cp->cp_xmit_rm); 3943ecc5693SSowmini Varadhan 3953ecc5693SSowmini Varadhan cp->cp_conn->c_trans->conn_free(cp->cp_transport_data); 3963ecc5693SSowmini Varadhan } 3973ecc5693SSowmini Varadhan 3982dc39357SAndy Grover /* 3992dc39357SAndy Grover * Stop and free a connection. 400ffcec0e1SZach Brown * 401ffcec0e1SZach Brown * This can only be used in very limited circumstances. It assumes that once 402ffcec0e1SZach Brown * the conn has been shutdown that no one else is referencing the connection. 403ffcec0e1SZach Brown * We can only ensure this in the rmmod path in the current code. 4042dc39357SAndy Grover */ 40500e0f34cSAndy Grover void rds_conn_destroy(struct rds_connection *conn) 40600e0f34cSAndy Grover { 407fe8ff6b5SZach Brown unsigned long flags; 40802105b2cSSowmini Varadhan int i; 40902105b2cSSowmini Varadhan struct rds_conn_path *cp; 41000e0f34cSAndy Grover 41100e0f34cSAndy Grover rdsdebug("freeing conn %p for %pI4 -> " 41200e0f34cSAndy Grover "%pI4\n", conn, &conn->c_laddr, 41300e0f34cSAndy Grover &conn->c_faddr); 41400e0f34cSAndy Grover 415c14b0366SSowmini Varadhan conn->c_destroy_in_prog = 1; 416abf45439SChris Mason /* Ensure conn will not be scheduled for reconnect */ 417abf45439SChris Mason spin_lock_irq(&rds_conn_lock); 418bcf50ef2SChris Mason hlist_del_init_rcu(&conn->c_hash_node); 419abf45439SChris Mason spin_unlock_irq(&rds_conn_lock); 420bcf50ef2SChris Mason synchronize_rcu(); 421bcf50ef2SChris Mason 422ffcec0e1SZach Brown /* shut the connection down */ 4233ecc5693SSowmini Varadhan for (i = 0; i < RDS_MPATH_WORKERS; i++) { 4243ecc5693SSowmini Varadhan cp = &conn->c_path[i]; 4253ecc5693SSowmini Varadhan rds_conn_path_destroy(cp); 4263ecc5693SSowmini Varadhan BUG_ON(!list_empty(&cp->cp_retrans)); 42700e0f34cSAndy Grover } 42800e0f34cSAndy Grover 42900e0f34cSAndy Grover /* 43000e0f34cSAndy Grover * The congestion maps aren't freed up here. They're 43100e0f34cSAndy Grover * freed by rds_cong_exit() after all the connections 43200e0f34cSAndy Grover * have been freed. 43300e0f34cSAndy Grover */ 43400e0f34cSAndy Grover rds_cong_remove_conn(conn); 43500e0f34cSAndy Grover 4368edc3affSSowmini Varadhan put_net(conn->c_net); 43700e0f34cSAndy Grover kmem_cache_free(rds_conn_slab, conn); 43800e0f34cSAndy Grover 439fe8ff6b5SZach Brown spin_lock_irqsave(&rds_conn_lock, flags); 44000e0f34cSAndy Grover rds_conn_count--; 441fe8ff6b5SZach Brown spin_unlock_irqrestore(&rds_conn_lock, flags); 44200e0f34cSAndy Grover } 443616b757aSAndy Grover EXPORT_SYMBOL_GPL(rds_conn_destroy); 44400e0f34cSAndy Grover 44500e0f34cSAndy Grover static void rds_conn_message_info(struct socket *sock, unsigned int len, 44600e0f34cSAndy Grover struct rds_info_iterator *iter, 44700e0f34cSAndy Grover struct rds_info_lengths *lens, 44800e0f34cSAndy Grover int want_send) 44900e0f34cSAndy Grover { 45000e0f34cSAndy Grover struct hlist_head *head; 45100e0f34cSAndy Grover struct list_head *list; 45200e0f34cSAndy Grover struct rds_connection *conn; 45300e0f34cSAndy Grover struct rds_message *rm; 45400e0f34cSAndy Grover unsigned int total = 0; 455501dcccdSZach Brown unsigned long flags; 45600e0f34cSAndy Grover size_t i; 457992c9ec5SSowmini Varadhan int j; 45800e0f34cSAndy Grover 45900e0f34cSAndy Grover len /= sizeof(struct rds_info_message); 46000e0f34cSAndy Grover 461bcf50ef2SChris Mason rcu_read_lock(); 46200e0f34cSAndy Grover 46300e0f34cSAndy Grover for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); 46400e0f34cSAndy Grover i++, head++) { 465b67bfe0dSSasha Levin hlist_for_each_entry_rcu(conn, head, c_hash_node) { 466992c9ec5SSowmini Varadhan struct rds_conn_path *cp; 46700e0f34cSAndy Grover 468992c9ec5SSowmini Varadhan for (j = 0; j < RDS_MPATH_WORKERS; j++) { 469992c9ec5SSowmini Varadhan cp = &conn->c_path[j]; 470992c9ec5SSowmini Varadhan if (want_send) 471992c9ec5SSowmini Varadhan list = &cp->cp_send_queue; 472992c9ec5SSowmini Varadhan else 473992c9ec5SSowmini Varadhan list = &cp->cp_retrans; 474992c9ec5SSowmini Varadhan 475992c9ec5SSowmini Varadhan spin_lock_irqsave(&cp->cp_lock, flags); 47600e0f34cSAndy Grover 47700e0f34cSAndy Grover /* XXX too lazy to maintain counts.. */ 47800e0f34cSAndy Grover list_for_each_entry(rm, list, m_conn_item) { 47900e0f34cSAndy Grover total++; 48000e0f34cSAndy Grover if (total <= len) 481992c9ec5SSowmini Varadhan rds_inc_info_copy(&rm->m_inc, 482992c9ec5SSowmini Varadhan iter, 48300e0f34cSAndy Grover conn->c_laddr, 484992c9ec5SSowmini Varadhan conn->c_faddr, 485992c9ec5SSowmini Varadhan 0); 48600e0f34cSAndy Grover } 48700e0f34cSAndy Grover 488992c9ec5SSowmini Varadhan spin_unlock_irqrestore(&cp->cp_lock, flags); 489992c9ec5SSowmini Varadhan if (!conn->c_trans->t_mp_capable) 490992c9ec5SSowmini Varadhan break; 491992c9ec5SSowmini Varadhan } 49200e0f34cSAndy Grover } 49300e0f34cSAndy Grover } 494bcf50ef2SChris Mason rcu_read_unlock(); 49500e0f34cSAndy Grover 49600e0f34cSAndy Grover lens->nr = total; 49700e0f34cSAndy Grover lens->each = sizeof(struct rds_info_message); 49800e0f34cSAndy Grover } 49900e0f34cSAndy Grover 50000e0f34cSAndy Grover static void rds_conn_message_info_send(struct socket *sock, unsigned int len, 50100e0f34cSAndy Grover struct rds_info_iterator *iter, 50200e0f34cSAndy Grover struct rds_info_lengths *lens) 50300e0f34cSAndy Grover { 50400e0f34cSAndy Grover rds_conn_message_info(sock, len, iter, lens, 1); 50500e0f34cSAndy Grover } 50600e0f34cSAndy Grover 50700e0f34cSAndy Grover static void rds_conn_message_info_retrans(struct socket *sock, 50800e0f34cSAndy Grover unsigned int len, 50900e0f34cSAndy Grover struct rds_info_iterator *iter, 51000e0f34cSAndy Grover struct rds_info_lengths *lens) 51100e0f34cSAndy Grover { 51200e0f34cSAndy Grover rds_conn_message_info(sock, len, iter, lens, 0); 51300e0f34cSAndy Grover } 51400e0f34cSAndy Grover 51500e0f34cSAndy Grover void rds_for_each_conn_info(struct socket *sock, unsigned int len, 51600e0f34cSAndy Grover struct rds_info_iterator *iter, 51700e0f34cSAndy Grover struct rds_info_lengths *lens, 51800e0f34cSAndy Grover int (*visitor)(struct rds_connection *, void *), 51900e0f34cSAndy Grover size_t item_len) 52000e0f34cSAndy Grover { 52100e0f34cSAndy Grover uint64_t buffer[(item_len + 7) / 8]; 52200e0f34cSAndy Grover struct hlist_head *head; 52300e0f34cSAndy Grover struct rds_connection *conn; 52400e0f34cSAndy Grover size_t i; 52500e0f34cSAndy Grover 526bcf50ef2SChris Mason rcu_read_lock(); 52700e0f34cSAndy Grover 52800e0f34cSAndy Grover lens->nr = 0; 52900e0f34cSAndy Grover lens->each = item_len; 53000e0f34cSAndy Grover 53100e0f34cSAndy Grover for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); 53200e0f34cSAndy Grover i++, head++) { 533b67bfe0dSSasha Levin hlist_for_each_entry_rcu(conn, head, c_hash_node) { 53400e0f34cSAndy Grover 53500e0f34cSAndy Grover /* XXX no c_lock usage.. */ 53600e0f34cSAndy Grover if (!visitor(conn, buffer)) 53700e0f34cSAndy Grover continue; 53800e0f34cSAndy Grover 53900e0f34cSAndy Grover /* We copy as much as we can fit in the buffer, 54000e0f34cSAndy Grover * but we count all items so that the caller 54100e0f34cSAndy Grover * can resize the buffer. */ 54200e0f34cSAndy Grover if (len >= item_len) { 54300e0f34cSAndy Grover rds_info_copy(iter, buffer, item_len); 54400e0f34cSAndy Grover len -= item_len; 54500e0f34cSAndy Grover } 54600e0f34cSAndy Grover lens->nr++; 54700e0f34cSAndy Grover } 54800e0f34cSAndy Grover } 549bcf50ef2SChris Mason rcu_read_unlock(); 55000e0f34cSAndy Grover } 551616b757aSAndy Grover EXPORT_SYMBOL_GPL(rds_for_each_conn_info); 55200e0f34cSAndy Grover 553bb789763SSantosh Shilimkar static void rds_walk_conn_path_info(struct socket *sock, unsigned int len, 554992c9ec5SSowmini Varadhan struct rds_info_iterator *iter, 555992c9ec5SSowmini Varadhan struct rds_info_lengths *lens, 556992c9ec5SSowmini Varadhan int (*visitor)(struct rds_conn_path *, void *), 557992c9ec5SSowmini Varadhan size_t item_len) 558992c9ec5SSowmini Varadhan { 559992c9ec5SSowmini Varadhan u64 buffer[(item_len + 7) / 8]; 560992c9ec5SSowmini Varadhan struct hlist_head *head; 561992c9ec5SSowmini Varadhan struct rds_connection *conn; 562992c9ec5SSowmini Varadhan size_t i; 563992c9ec5SSowmini Varadhan int j; 564992c9ec5SSowmini Varadhan 565992c9ec5SSowmini Varadhan rcu_read_lock(); 566992c9ec5SSowmini Varadhan 567992c9ec5SSowmini Varadhan lens->nr = 0; 568992c9ec5SSowmini Varadhan lens->each = item_len; 569992c9ec5SSowmini Varadhan 570992c9ec5SSowmini Varadhan for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); 571992c9ec5SSowmini Varadhan i++, head++) { 572992c9ec5SSowmini Varadhan hlist_for_each_entry_rcu(conn, head, c_hash_node) { 573992c9ec5SSowmini Varadhan struct rds_conn_path *cp; 574992c9ec5SSowmini Varadhan 575992c9ec5SSowmini Varadhan for (j = 0; j < RDS_MPATH_WORKERS; j++) { 576992c9ec5SSowmini Varadhan cp = &conn->c_path[j]; 577992c9ec5SSowmini Varadhan 578992c9ec5SSowmini Varadhan /* XXX no cp_lock usage.. */ 579992c9ec5SSowmini Varadhan if (!visitor(cp, buffer)) 580992c9ec5SSowmini Varadhan continue; 581992c9ec5SSowmini Varadhan if (!conn->c_trans->t_mp_capable) 582992c9ec5SSowmini Varadhan break; 583992c9ec5SSowmini Varadhan } 584992c9ec5SSowmini Varadhan 585992c9ec5SSowmini Varadhan /* We copy as much as we can fit in the buffer, 586992c9ec5SSowmini Varadhan * but we count all items so that the caller 587992c9ec5SSowmini Varadhan * can resize the buffer. 588992c9ec5SSowmini Varadhan */ 589992c9ec5SSowmini Varadhan if (len >= item_len) { 590992c9ec5SSowmini Varadhan rds_info_copy(iter, buffer, item_len); 591992c9ec5SSowmini Varadhan len -= item_len; 592992c9ec5SSowmini Varadhan } 593992c9ec5SSowmini Varadhan lens->nr++; 594992c9ec5SSowmini Varadhan } 595992c9ec5SSowmini Varadhan } 596992c9ec5SSowmini Varadhan rcu_read_unlock(); 597992c9ec5SSowmini Varadhan } 598992c9ec5SSowmini Varadhan 599992c9ec5SSowmini Varadhan static int rds_conn_info_visitor(struct rds_conn_path *cp, void *buffer) 60000e0f34cSAndy Grover { 60100e0f34cSAndy Grover struct rds_info_connection *cinfo = buffer; 60200e0f34cSAndy Grover 603992c9ec5SSowmini Varadhan cinfo->next_tx_seq = cp->cp_next_tx_seq; 604992c9ec5SSowmini Varadhan cinfo->next_rx_seq = cp->cp_next_rx_seq; 605992c9ec5SSowmini Varadhan cinfo->laddr = cp->cp_conn->c_laddr; 606992c9ec5SSowmini Varadhan cinfo->faddr = cp->cp_conn->c_faddr; 607992c9ec5SSowmini Varadhan strncpy(cinfo->transport, cp->cp_conn->c_trans->t_name, 60800e0f34cSAndy Grover sizeof(cinfo->transport)); 60900e0f34cSAndy Grover cinfo->flags = 0; 61000e0f34cSAndy Grover 611992c9ec5SSowmini Varadhan rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags), 6120f4b1c7eSZach Brown SENDING); 61300e0f34cSAndy Grover /* XXX Future: return the state rather than these funky bits */ 61400e0f34cSAndy Grover rds_conn_info_set(cinfo->flags, 615992c9ec5SSowmini Varadhan atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING, 61600e0f34cSAndy Grover CONNECTING); 61700e0f34cSAndy Grover rds_conn_info_set(cinfo->flags, 618992c9ec5SSowmini Varadhan atomic_read(&cp->cp_state) == RDS_CONN_UP, 61900e0f34cSAndy Grover CONNECTED); 62000e0f34cSAndy Grover return 1; 62100e0f34cSAndy Grover } 62200e0f34cSAndy Grover 62300e0f34cSAndy Grover static void rds_conn_info(struct socket *sock, unsigned int len, 62400e0f34cSAndy Grover struct rds_info_iterator *iter, 62500e0f34cSAndy Grover struct rds_info_lengths *lens) 62600e0f34cSAndy Grover { 627992c9ec5SSowmini Varadhan rds_walk_conn_path_info(sock, len, iter, lens, 62800e0f34cSAndy Grover rds_conn_info_visitor, 62900e0f34cSAndy Grover sizeof(struct rds_info_connection)); 63000e0f34cSAndy Grover } 63100e0f34cSAndy Grover 632ef87b7eaSZach Brown int rds_conn_init(void) 63300e0f34cSAndy Grover { 63400e0f34cSAndy Grover rds_conn_slab = kmem_cache_create("rds_connection", 63500e0f34cSAndy Grover sizeof(struct rds_connection), 63600e0f34cSAndy Grover 0, 0, NULL); 6378690bfa1SAndy Grover if (!rds_conn_slab) 63800e0f34cSAndy Grover return -ENOMEM; 63900e0f34cSAndy Grover 64000e0f34cSAndy Grover rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info); 64100e0f34cSAndy Grover rds_info_register_func(RDS_INFO_SEND_MESSAGES, 64200e0f34cSAndy Grover rds_conn_message_info_send); 64300e0f34cSAndy Grover rds_info_register_func(RDS_INFO_RETRANS_MESSAGES, 64400e0f34cSAndy Grover rds_conn_message_info_retrans); 64500e0f34cSAndy Grover 64600e0f34cSAndy Grover return 0; 64700e0f34cSAndy Grover } 64800e0f34cSAndy Grover 64900e0f34cSAndy Grover void rds_conn_exit(void) 65000e0f34cSAndy Grover { 65100e0f34cSAndy Grover rds_loop_exit(); 65200e0f34cSAndy Grover 65300e0f34cSAndy Grover WARN_ON(!hlist_empty(rds_conn_hash)); 65400e0f34cSAndy Grover 65500e0f34cSAndy Grover kmem_cache_destroy(rds_conn_slab); 65600e0f34cSAndy Grover 65700e0f34cSAndy Grover rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info); 65800e0f34cSAndy Grover rds_info_deregister_func(RDS_INFO_SEND_MESSAGES, 65900e0f34cSAndy Grover rds_conn_message_info_send); 66000e0f34cSAndy Grover rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES, 66100e0f34cSAndy Grover rds_conn_message_info_retrans); 66200e0f34cSAndy Grover } 66300e0f34cSAndy Grover 66400e0f34cSAndy Grover /* 66500e0f34cSAndy Grover * Force a disconnect 66600e0f34cSAndy Grover */ 667*aed20a53SSowmini Varadhan void rds_conn_path_drop(struct rds_conn_path *cp, bool destroy) 6680cb43965SSowmini Varadhan { 6690cb43965SSowmini Varadhan atomic_set(&cp->cp_state, RDS_CONN_ERROR); 670*aed20a53SSowmini Varadhan 671*aed20a53SSowmini Varadhan if (!destroy && cp->cp_conn->c_destroy_in_prog) 672*aed20a53SSowmini Varadhan return; 673*aed20a53SSowmini Varadhan 6740cb43965SSowmini Varadhan queue_work(rds_wq, &cp->cp_down_w); 6750cb43965SSowmini Varadhan } 6760cb43965SSowmini Varadhan EXPORT_SYMBOL_GPL(rds_conn_path_drop); 6770cb43965SSowmini Varadhan 67800e0f34cSAndy Grover void rds_conn_drop(struct rds_connection *conn) 67900e0f34cSAndy Grover { 6805916e2c1SSowmini Varadhan WARN_ON(conn->c_trans->t_mp_capable); 681*aed20a53SSowmini Varadhan rds_conn_path_drop(&conn->c_path[0], false); 68200e0f34cSAndy Grover } 683616b757aSAndy Grover EXPORT_SYMBOL_GPL(rds_conn_drop); 68400e0f34cSAndy Grover 68500e0f34cSAndy Grover /* 686f3c6808dSZach Brown * If the connection is down, trigger a connect. We may have scheduled a 687f3c6808dSZach Brown * delayed reconnect however - in this case we should not interfere. 688f3c6808dSZach Brown */ 6893c0a5900SSowmini Varadhan void rds_conn_path_connect_if_down(struct rds_conn_path *cp) 6903c0a5900SSowmini Varadhan { 6913c0a5900SSowmini Varadhan if (rds_conn_path_state(cp) == RDS_CONN_DOWN && 6923c0a5900SSowmini Varadhan !test_and_set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags)) 6933c0a5900SSowmini Varadhan queue_delayed_work(rds_wq, &cp->cp_conn_w, 0); 6943c0a5900SSowmini Varadhan } 6951a0e100fSSowmini Varadhan EXPORT_SYMBOL_GPL(rds_conn_path_connect_if_down); 6963c0a5900SSowmini Varadhan 697f3c6808dSZach Brown void rds_conn_connect_if_down(struct rds_connection *conn) 698f3c6808dSZach Brown { 6993c0a5900SSowmini Varadhan WARN_ON(conn->c_trans->t_mp_capable); 7003c0a5900SSowmini Varadhan rds_conn_path_connect_if_down(&conn->c_path[0]); 701f3c6808dSZach Brown } 702f3c6808dSZach Brown EXPORT_SYMBOL_GPL(rds_conn_connect_if_down); 703f3c6808dSZach Brown 704fb1b3dc4SSowmini Varadhan void 705fb1b3dc4SSowmini Varadhan __rds_conn_path_error(struct rds_conn_path *cp, const char *fmt, ...) 706fb1b3dc4SSowmini Varadhan { 707fb1b3dc4SSowmini Varadhan va_list ap; 708fb1b3dc4SSowmini Varadhan 709fb1b3dc4SSowmini Varadhan va_start(ap, fmt); 710fb1b3dc4SSowmini Varadhan vprintk(fmt, ap); 711fb1b3dc4SSowmini Varadhan va_end(ap); 712fb1b3dc4SSowmini Varadhan 713*aed20a53SSowmini Varadhan rds_conn_path_drop(cp, false); 714fb1b3dc4SSowmini Varadhan } 715