blob: da6da57e5f36b5cc13a5bc92abfedb6a5ccea45d [file] [log] [blame]
Andy Grover00e0f342009-02-24 15:30:23 +00001/*
2 * Copyright (c) 2006 Oracle. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34#include <linux/list.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
Paul Gortmakerbc3b2d72011-07-15 11:47:34 -040036#include <linux/export.h>
Andy Grover00e0f342009-02-24 15:30:23 +000037#include <net/inet_hashtables.h>
38
39#include "rds.h"
40#include "loop.h"
Andy Grover00e0f342009-02-24 15:30:23 +000041
42#define RDS_CONNECTION_HASH_BITS 12
43#define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS)
44#define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1)
45
46/* converting this to RCU is a chore for another day.. */
47static DEFINE_SPINLOCK(rds_conn_lock);
48static unsigned long rds_conn_count;
49static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES];
50static struct kmem_cache *rds_conn_slab;
51
52static struct hlist_head *rds_conn_bucket(__be32 laddr, __be32 faddr)
53{
Hannes Frederic Sowa1bbdcee2013-10-19 21:48:57 +020054 static u32 rds_hash_secret __read_mostly;
55
56 unsigned long hash;
57
58 net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret));
59
Andy Grover00e0f342009-02-24 15:30:23 +000060 /* Pass NULL, don't need struct net for hash */
Hannes Frederic Sowa1bbdcee2013-10-19 21:48:57 +020061 hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
62 be32_to_cpu(faddr), 0,
63 rds_hash_secret);
Andy Grover00e0f342009-02-24 15:30:23 +000064 return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
65}
66
67#define rds_conn_info_set(var, test, suffix) do { \
68 if (test) \
69 var |= RDS_INFO_CONNECTION_FLAG_##suffix; \
70} while (0)
71
Chris Masonbcf50ef2010-05-11 15:15:15 -070072/* rcu read lock must be held or the connection spinlock */
Andy Grover00e0f342009-02-24 15:30:23 +000073static struct rds_connection *rds_conn_lookup(struct hlist_head *head,
74 __be32 laddr, __be32 faddr,
75 struct rds_transport *trans)
76{
77 struct rds_connection *conn, *ret = NULL;
Andy Grover00e0f342009-02-24 15:30:23 +000078
Sasha Levinb67bfe02013-02-27 17:06:00 -080079 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +000080 if (conn->c_faddr == faddr && conn->c_laddr == laddr &&
81 conn->c_trans == trans) {
82 ret = conn;
83 break;
84 }
85 }
86 rdsdebug("returning conn %p for %pI4 -> %pI4\n", ret,
87 &laddr, &faddr);
88 return ret;
89}
90
91/*
92 * This is called by transports as they're bringing down a connection.
93 * It clears partial message state so that the transport can start sending
94 * and receiving over this connection again in the future. It is up to
95 * the transport to have serialized this call with its send and recv.
96 */
stephen hemmingerff51bf82010-10-19 08:08:33 +000097static void rds_conn_reset(struct rds_connection *conn)
Andy Grover00e0f342009-02-24 15:30:23 +000098{
99 rdsdebug("connection %pI4 to %pI4 reset\n",
100 &conn->c_laddr, &conn->c_faddr);
101
102 rds_stats_inc(s_conn_reset);
103 rds_send_reset(conn);
104 conn->c_flags = 0;
105
106 /* Do not clear next_rx_seq here, else we cannot distinguish
107 * retransmitted packets from new packets, and will hand all
108 * of them to the application. That is not consistent with the
109 * reliability guarantees of RDS. */
110}
111
112/*
113 * There is only every one 'conn' for a given pair of addresses in the
114 * system at a time. They contain messages to be retransmitted and so
115 * span the lifetime of the actual underlying transport connections.
116 *
117 * For now they are not garbage collected once they're created. They
118 * are torn down as the module is removed, if ever.
119 */
120static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
121 struct rds_transport *trans, gfp_t gfp,
122 int is_outgoing)
123{
Andy Grovercb244052009-07-17 13:13:36 +0000124 struct rds_connection *conn, *parent = NULL;
Andy Grover00e0f342009-02-24 15:30:23 +0000125 struct hlist_head *head = rds_conn_bucket(laddr, faddr);
Zach Brown5adb5bc2010-07-23 10:32:31 -0700126 struct rds_transport *loop_trans;
Andy Grover00e0f342009-02-24 15:30:23 +0000127 unsigned long flags;
128 int ret;
Sowmini Varadhanf711a6a2015-05-05 15:20:51 -0400129 struct rds_transport *otrans = trans;
Andy Grover00e0f342009-02-24 15:30:23 +0000130
Sowmini Varadhanf711a6a2015-05-05 15:20:51 -0400131 if (!is_outgoing && otrans->t_type == RDS_TRANS_TCP)
132 goto new_conn;
Chris Masonbcf50ef2010-05-11 15:15:15 -0700133 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000134 conn = rds_conn_lookup(head, laddr, faddr, trans);
Joe Perchesf64f9e72009-11-29 16:55:45 -0800135 if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport &&
Sowmini Varadhan1789b2c072015-04-08 12:33:46 -0400136 laddr == faddr && !is_outgoing) {
Andy Grover00e0f342009-02-24 15:30:23 +0000137 /* This is a looped back IB connection, and we're
138 * called by the code handling the incoming connect.
139 * We need a second connection object into which we
140 * can stick the other QP. */
141 parent = conn;
142 conn = parent->c_passive;
143 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700144 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000145 if (conn)
146 goto out;
147
Sowmini Varadhanf711a6a2015-05-05 15:20:51 -0400148new_conn:
Wei Yongjun05a178e2009-04-09 14:09:44 +0000149 conn = kmem_cache_zalloc(rds_conn_slab, gfp);
Andy Grover8690bfa2010-01-12 11:56:44 -0800150 if (!conn) {
Andy Grover00e0f342009-02-24 15:30:23 +0000151 conn = ERR_PTR(-ENOMEM);
152 goto out;
153 }
154
Andy Grover00e0f342009-02-24 15:30:23 +0000155 INIT_HLIST_NODE(&conn->c_hash_node);
Andy Grover00e0f342009-02-24 15:30:23 +0000156 conn->c_laddr = laddr;
157 conn->c_faddr = faddr;
158 spin_lock_init(&conn->c_lock);
159 conn->c_next_tx_seq = 1;
160
Zach Brown0f4b1c72010-06-04 14:41:41 -0700161 init_waitqueue_head(&conn->c_waitq);
Andy Grover00e0f342009-02-24 15:30:23 +0000162 INIT_LIST_HEAD(&conn->c_send_queue);
163 INIT_LIST_HEAD(&conn->c_retrans);
164
165 ret = rds_cong_get_maps(conn);
166 if (ret) {
167 kmem_cache_free(rds_conn_slab, conn);
168 conn = ERR_PTR(ret);
169 goto out;
170 }
171
172 /*
173 * This is where a connection becomes loopback. If *any* RDS sockets
174 * can bind to the destination address then we'd rather the messages
175 * flow through loopback rather than either transport.
176 */
Zach Brown5adb5bc2010-07-23 10:32:31 -0700177 loop_trans = rds_trans_get_preferred(faddr);
178 if (loop_trans) {
179 rds_trans_put(loop_trans);
Andy Grover00e0f342009-02-24 15:30:23 +0000180 conn->c_loopback = 1;
181 if (is_outgoing && trans->t_prefer_loopback) {
182 /* "outgoing" connection - and the transport
183 * says it wants the connection handled by the
184 * loopback transport. This is what TCP does.
185 */
186 trans = &rds_loop_transport;
187 }
188 }
189
190 conn->c_trans = trans;
191
192 ret = trans->conn_alloc(conn, gfp);
193 if (ret) {
194 kmem_cache_free(rds_conn_slab, conn);
195 conn = ERR_PTR(ret);
196 goto out;
197 }
198
199 atomic_set(&conn->c_state, RDS_CONN_DOWN);
Sowmini Varadhan443be0e2015-04-08 12:33:47 -0400200 conn->c_send_gen = 0;
Andy Grover00e0f342009-02-24 15:30:23 +0000201 conn->c_reconnect_jiffies = 0;
202 INIT_DELAYED_WORK(&conn->c_send_w, rds_send_worker);
203 INIT_DELAYED_WORK(&conn->c_recv_w, rds_recv_worker);
204 INIT_DELAYED_WORK(&conn->c_conn_w, rds_connect_worker);
205 INIT_WORK(&conn->c_down_w, rds_shutdown_worker);
206 mutex_init(&conn->c_cm_lock);
207 conn->c_flags = 0;
208
209 rdsdebug("allocated conn %p for %pI4 -> %pI4 over %s %s\n",
210 conn, &laddr, &faddr,
211 trans->t_name ? trans->t_name : "[unknown]",
212 is_outgoing ? "(outgoing)" : "");
213
Andy Grovercb244052009-07-17 13:13:36 +0000214 /*
215 * Since we ran without holding the conn lock, someone could
216 * have created the same conn (either normal or passive) in the
217 * interim. We check while holding the lock. If we won, we complete
218 * init and return our conn. If we lost, we rollback and return the
219 * other one.
220 */
Andy Grover00e0f342009-02-24 15:30:23 +0000221 spin_lock_irqsave(&rds_conn_lock, flags);
Andy Grovercb244052009-07-17 13:13:36 +0000222 if (parent) {
223 /* Creating passive conn */
224 if (parent->c_passive) {
225 trans->conn_free(conn->c_transport_data);
226 kmem_cache_free(rds_conn_slab, conn);
227 conn = parent->c_passive;
228 } else {
Andy Grover00e0f342009-02-24 15:30:23 +0000229 parent->c_passive = conn;
Andy Grovercb244052009-07-17 13:13:36 +0000230 rds_cong_add_conn(conn);
231 rds_conn_count++;
232 }
Andy Grover00e0f342009-02-24 15:30:23 +0000233 } else {
Andy Grovercb244052009-07-17 13:13:36 +0000234 /* Creating normal conn */
235 struct rds_connection *found;
Andy Grover00e0f342009-02-24 15:30:23 +0000236
Sowmini Varadhanc82ac7e2015-05-05 15:20:52 -0400237 if (!is_outgoing && otrans->t_type == RDS_TRANS_TCP)
238 found = NULL;
239 else
240 found = rds_conn_lookup(head, laddr, faddr, trans);
Andy Grovercb244052009-07-17 13:13:36 +0000241 if (found) {
242 trans->conn_free(conn->c_transport_data);
243 kmem_cache_free(rds_conn_slab, conn);
244 conn = found;
245 } else {
Sowmini Varadhanc82ac7e2015-05-05 15:20:52 -0400246 if ((is_outgoing && otrans->t_type == RDS_TRANS_TCP) ||
247 (otrans->t_type != RDS_TRANS_TCP)) {
248 /* Only the active side should be added to
249 * reconnect list for TCP.
250 */
251 hlist_add_head_rcu(&conn->c_hash_node, head);
252 }
Andy Grovercb244052009-07-17 13:13:36 +0000253 rds_cong_add_conn(conn);
254 rds_conn_count++;
255 }
256 }
Andy Grover00e0f342009-02-24 15:30:23 +0000257 spin_unlock_irqrestore(&rds_conn_lock, flags);
258
259out:
260 return conn;
261}
262
263struct rds_connection *rds_conn_create(__be32 laddr, __be32 faddr,
264 struct rds_transport *trans, gfp_t gfp)
265{
266 return __rds_conn_create(laddr, faddr, trans, gfp, 0);
267}
Andy Grover616b7572009-08-21 12:28:32 +0000268EXPORT_SYMBOL_GPL(rds_conn_create);
Andy Grover00e0f342009-02-24 15:30:23 +0000269
270struct rds_connection *rds_conn_create_outgoing(__be32 laddr, __be32 faddr,
271 struct rds_transport *trans, gfp_t gfp)
272{
273 return __rds_conn_create(laddr, faddr, trans, gfp, 1);
274}
Andy Grover616b7572009-08-21 12:28:32 +0000275EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
Andy Grover00e0f342009-02-24 15:30:23 +0000276
Andy Grover2dc39352010-06-11 13:49:13 -0700277void rds_conn_shutdown(struct rds_connection *conn)
278{
279 /* shut it down unless it's down already */
280 if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_DOWN)) {
281 /*
282 * Quiesce the connection mgmt handlers before we start tearing
283 * things down. We don't hold the mutex for the entire
284 * duration of the shutdown operation, else we may be
285 * deadlocking with the CM handler. Instead, the CM event
286 * handler is supposed to check for state DISCONNECTING
287 */
288 mutex_lock(&conn->c_cm_lock);
289 if (!rds_conn_transition(conn, RDS_CONN_UP, RDS_CONN_DISCONNECTING)
290 && !rds_conn_transition(conn, RDS_CONN_ERROR, RDS_CONN_DISCONNECTING)) {
291 rds_conn_error(conn, "shutdown called in state %d\n",
292 atomic_read(&conn->c_state));
293 mutex_unlock(&conn->c_cm_lock);
294 return;
295 }
296 mutex_unlock(&conn->c_cm_lock);
297
Zach Brown0f4b1c72010-06-04 14:41:41 -0700298 wait_event(conn->c_waitq,
299 !test_bit(RDS_IN_XMIT, &conn->c_flags));
Chris Mason7e3f2952010-05-11 15:11:11 -0700300
Andy Grover2dc39352010-06-11 13:49:13 -0700301 conn->c_trans->conn_shutdown(conn);
302 rds_conn_reset(conn);
Andy Grover2dc39352010-06-11 13:49:13 -0700303
304 if (!rds_conn_transition(conn, RDS_CONN_DISCONNECTING, RDS_CONN_DOWN)) {
305 /* This can happen - eg when we're in the middle of tearing
306 * down the connection, and someone unloads the rds module.
307 * Quite reproduceable with loopback connections.
308 * Mostly harmless.
309 */
310 rds_conn_error(conn,
311 "%s: failed to transition to state DOWN, "
312 "current state is %d\n",
313 __func__,
314 atomic_read(&conn->c_state));
315 return;
316 }
317 }
318
319 /* Then reconnect if it's still live.
320 * The passive side of an IB loopback connection is never added
321 * to the conn hash, so we never trigger a reconnect on this
322 * conn - the reconnect is always triggered by the active peer. */
323 cancel_delayed_work_sync(&conn->c_conn_w);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700324 rcu_read_lock();
325 if (!hlist_unhashed(&conn->c_hash_node)) {
326 rcu_read_unlock();
Andy Grover2dc39352010-06-11 13:49:13 -0700327 rds_queue_reconnect(conn);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700328 } else {
329 rcu_read_unlock();
330 }
Andy Grover2dc39352010-06-11 13:49:13 -0700331}
332
333/*
334 * Stop and free a connection.
Zach Brownffcec0e2010-07-23 10:36:58 -0700335 *
336 * This can only be used in very limited circumstances. It assumes that once
337 * the conn has been shutdown that no one else is referencing the connection.
338 * We can only ensure this in the rmmod path in the current code.
Andy Grover2dc39352010-06-11 13:49:13 -0700339 */
Andy Grover00e0f342009-02-24 15:30:23 +0000340void rds_conn_destroy(struct rds_connection *conn)
341{
342 struct rds_message *rm, *rtmp;
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700343 unsigned long flags;
Andy Grover00e0f342009-02-24 15:30:23 +0000344
345 rdsdebug("freeing conn %p for %pI4 -> "
346 "%pI4\n", conn, &conn->c_laddr,
347 &conn->c_faddr);
348
Chris Masonabf45432010-05-11 15:14:52 -0700349 /* Ensure conn will not be scheduled for reconnect */
350 spin_lock_irq(&rds_conn_lock);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700351 hlist_del_init_rcu(&conn->c_hash_node);
Chris Masonabf45432010-05-11 15:14:52 -0700352 spin_unlock_irq(&rds_conn_lock);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700353 synchronize_rcu();
354
Zach Brownffcec0e2010-07-23 10:36:58 -0700355 /* shut the connection down */
356 rds_conn_drop(conn);
357 flush_work(&conn->c_down_w);
Andy Grover00e0f342009-02-24 15:30:23 +0000358
Zach Brown45180712010-07-23 10:37:33 -0700359 /* make sure lingering queued work won't try to ref the conn */
360 cancel_delayed_work_sync(&conn->c_send_w);
361 cancel_delayed_work_sync(&conn->c_recv_w);
362
Andy Grover00e0f342009-02-24 15:30:23 +0000363 /* tear down queued messages */
364 list_for_each_entry_safe(rm, rtmp,
365 &conn->c_send_queue,
366 m_conn_item) {
367 list_del_init(&rm->m_conn_item);
368 BUG_ON(!list_empty(&rm->m_sock_item));
369 rds_message_put(rm);
370 }
371 if (conn->c_xmit_rm)
372 rds_message_put(conn->c_xmit_rm);
373
374 conn->c_trans->conn_free(conn->c_transport_data);
375
376 /*
377 * The congestion maps aren't freed up here. They're
378 * freed by rds_cong_exit() after all the connections
379 * have been freed.
380 */
381 rds_cong_remove_conn(conn);
382
383 BUG_ON(!list_empty(&conn->c_retrans));
384 kmem_cache_free(rds_conn_slab, conn);
385
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700386 spin_lock_irqsave(&rds_conn_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000387 rds_conn_count--;
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700388 spin_unlock_irqrestore(&rds_conn_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000389}
Andy Grover616b7572009-08-21 12:28:32 +0000390EXPORT_SYMBOL_GPL(rds_conn_destroy);
Andy Grover00e0f342009-02-24 15:30:23 +0000391
392static void rds_conn_message_info(struct socket *sock, unsigned int len,
393 struct rds_info_iterator *iter,
394 struct rds_info_lengths *lens,
395 int want_send)
396{
397 struct hlist_head *head;
Andy Grover00e0f342009-02-24 15:30:23 +0000398 struct list_head *list;
399 struct rds_connection *conn;
400 struct rds_message *rm;
Andy Grover00e0f342009-02-24 15:30:23 +0000401 unsigned int total = 0;
Zach Brown501dccc2010-06-04 14:25:27 -0700402 unsigned long flags;
Andy Grover00e0f342009-02-24 15:30:23 +0000403 size_t i;
404
405 len /= sizeof(struct rds_info_message);
406
Chris Masonbcf50ef2010-05-11 15:15:15 -0700407 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000408
409 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
410 i++, head++) {
Sasha Levinb67bfe02013-02-27 17:06:00 -0800411 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +0000412 if (want_send)
413 list = &conn->c_send_queue;
414 else
415 list = &conn->c_retrans;
416
Zach Brown501dccc2010-06-04 14:25:27 -0700417 spin_lock_irqsave(&conn->c_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000418
419 /* XXX too lazy to maintain counts.. */
420 list_for_each_entry(rm, list, m_conn_item) {
421 total++;
422 if (total <= len)
423 rds_inc_info_copy(&rm->m_inc, iter,
424 conn->c_laddr,
425 conn->c_faddr, 0);
426 }
427
Zach Brown501dccc2010-06-04 14:25:27 -0700428 spin_unlock_irqrestore(&conn->c_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000429 }
430 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700431 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000432
433 lens->nr = total;
434 lens->each = sizeof(struct rds_info_message);
435}
436
437static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
438 struct rds_info_iterator *iter,
439 struct rds_info_lengths *lens)
440{
441 rds_conn_message_info(sock, len, iter, lens, 1);
442}
443
444static void rds_conn_message_info_retrans(struct socket *sock,
445 unsigned int len,
446 struct rds_info_iterator *iter,
447 struct rds_info_lengths *lens)
448{
449 rds_conn_message_info(sock, len, iter, lens, 0);
450}
451
452void rds_for_each_conn_info(struct socket *sock, unsigned int len,
453 struct rds_info_iterator *iter,
454 struct rds_info_lengths *lens,
455 int (*visitor)(struct rds_connection *, void *),
456 size_t item_len)
457{
458 uint64_t buffer[(item_len + 7) / 8];
459 struct hlist_head *head;
Andy Grover00e0f342009-02-24 15:30:23 +0000460 struct rds_connection *conn;
Andy Grover00e0f342009-02-24 15:30:23 +0000461 size_t i;
462
Chris Masonbcf50ef2010-05-11 15:15:15 -0700463 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000464
465 lens->nr = 0;
466 lens->each = item_len;
467
468 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
469 i++, head++) {
Sasha Levinb67bfe02013-02-27 17:06:00 -0800470 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +0000471
472 /* XXX no c_lock usage.. */
473 if (!visitor(conn, buffer))
474 continue;
475
476 /* We copy as much as we can fit in the buffer,
477 * but we count all items so that the caller
478 * can resize the buffer. */
479 if (len >= item_len) {
480 rds_info_copy(iter, buffer, item_len);
481 len -= item_len;
482 }
483 lens->nr++;
484 }
485 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700486 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000487}
Andy Grover616b7572009-08-21 12:28:32 +0000488EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
Andy Grover00e0f342009-02-24 15:30:23 +0000489
490static int rds_conn_info_visitor(struct rds_connection *conn,
491 void *buffer)
492{
493 struct rds_info_connection *cinfo = buffer;
494
495 cinfo->next_tx_seq = conn->c_next_tx_seq;
496 cinfo->next_rx_seq = conn->c_next_rx_seq;
497 cinfo->laddr = conn->c_laddr;
498 cinfo->faddr = conn->c_faddr;
499 strncpy(cinfo->transport, conn->c_trans->t_name,
500 sizeof(cinfo->transport));
501 cinfo->flags = 0;
502
Zach Brown0f4b1c72010-06-04 14:41:41 -0700503 rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &conn->c_flags),
504 SENDING);
Andy Grover00e0f342009-02-24 15:30:23 +0000505 /* XXX Future: return the state rather than these funky bits */
506 rds_conn_info_set(cinfo->flags,
507 atomic_read(&conn->c_state) == RDS_CONN_CONNECTING,
508 CONNECTING);
509 rds_conn_info_set(cinfo->flags,
510 atomic_read(&conn->c_state) == RDS_CONN_UP,
511 CONNECTED);
512 return 1;
513}
514
515static void rds_conn_info(struct socket *sock, unsigned int len,
516 struct rds_info_iterator *iter,
517 struct rds_info_lengths *lens)
518{
519 rds_for_each_conn_info(sock, len, iter, lens,
520 rds_conn_info_visitor,
521 sizeof(struct rds_info_connection));
522}
523
Zach Brownef87b7e2010-07-09 12:26:20 -0700524int rds_conn_init(void)
Andy Grover00e0f342009-02-24 15:30:23 +0000525{
526 rds_conn_slab = kmem_cache_create("rds_connection",
527 sizeof(struct rds_connection),
528 0, 0, NULL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800529 if (!rds_conn_slab)
Andy Grover00e0f342009-02-24 15:30:23 +0000530 return -ENOMEM;
531
532 rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
533 rds_info_register_func(RDS_INFO_SEND_MESSAGES,
534 rds_conn_message_info_send);
535 rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
536 rds_conn_message_info_retrans);
537
538 return 0;
539}
540
541void rds_conn_exit(void)
542{
543 rds_loop_exit();
544
545 WARN_ON(!hlist_empty(rds_conn_hash));
546
547 kmem_cache_destroy(rds_conn_slab);
548
549 rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
550 rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
551 rds_conn_message_info_send);
552 rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
553 rds_conn_message_info_retrans);
554}
555
556/*
557 * Force a disconnect
558 */
559void rds_conn_drop(struct rds_connection *conn)
560{
561 atomic_set(&conn->c_state, RDS_CONN_ERROR);
562 queue_work(rds_wq, &conn->c_down_w);
563}
Andy Grover616b7572009-08-21 12:28:32 +0000564EXPORT_SYMBOL_GPL(rds_conn_drop);
Andy Grover00e0f342009-02-24 15:30:23 +0000565
566/*
Zach Brownf3c68082010-05-24 13:14:36 -0700567 * If the connection is down, trigger a connect. We may have scheduled a
568 * delayed reconnect however - in this case we should not interfere.
569 */
570void rds_conn_connect_if_down(struct rds_connection *conn)
571{
572 if (rds_conn_state(conn) == RDS_CONN_DOWN &&
573 !test_and_set_bit(RDS_RECONNECT_PENDING, &conn->c_flags))
574 queue_delayed_work(rds_wq, &conn->c_conn_w, 0);
575}
576EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
577
578/*
Andy Grover00e0f342009-02-24 15:30:23 +0000579 * An error occurred on the connection
580 */
581void
582__rds_conn_error(struct rds_connection *conn, const char *fmt, ...)
583{
584 va_list ap;
585
586 va_start(ap, fmt);
587 vprintk(fmt, ap);
588 va_end(ap);
589
590 rds_conn_drop(conn);
591}