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CommitLineData
00e0f34c
AG
1/*
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>
5a0e3ad6 35#include <linux/slab.h>
bc3b2d7f 36#include <linux/export.h>
00e0f34c
AG
37#include <net/inet_hashtables.h>
38
39#include "rds.h"
40#include "loop.h"
00e0f34c
AG
41
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{
1bbdceef
HFS
54 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
00e0f34c 60 /* Pass NULL, don't need struct net for hash */
1bbdceef
HFS
61 hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
62 be32_to_cpu(faddr), 0,
63 rds_hash_secret);
00e0f34c
AG
64 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
bcf50ef2 72/* rcu read lock must be held or the connection spinlock */
8f384c01
SV
73static struct rds_connection *rds_conn_lookup(struct net *net,
74 struct hlist_head *head,
00e0f34c
AG
75 __be32 laddr, __be32 faddr,
76 struct rds_transport *trans)
77{
78 struct rds_connection *conn, *ret = NULL;
00e0f34c 79
b67bfe0d 80 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
00e0f34c 81 if (conn->c_faddr == faddr && conn->c_laddr == laddr &&
8f384c01 82 conn->c_trans == trans && net == rds_conn_net(conn)) {
00e0f34c
AG
83 ret = conn;
84 break;
85 }
86 }
87 rdsdebug("returning conn %p for %pI4 -> %pI4\n", ret,
88 &laddr, &faddr);
89 return ret;
90}
91
92/*
93 * This is called by transports as they're bringing down a connection.
94 * It clears partial message state so that the transport can start sending
95 * and receiving over this connection again in the future. It is up to
96 * the transport to have serialized this call with its send and recv.
97 */
d769ef81 98static void rds_conn_path_reset(struct rds_conn_path *cp)
00e0f34c 99{
d769ef81
SV
100 struct rds_connection *conn = cp->cp_conn;
101
00e0f34c
AG
102 rdsdebug("connection %pI4 to %pI4 reset\n",
103 &conn->c_laddr, &conn->c_faddr);
104
105 rds_stats_inc(s_conn_reset);
d769ef81
SV
106 rds_send_path_reset(cp);
107 cp->cp_flags = 0;
00e0f34c
AG
108
109 /* Do not clear next_rx_seq here, else we cannot distinguish
110 * retransmitted packets from new packets, and will hand all
111 * of them to the application. That is not consistent with the
112 * reliability guarantees of RDS. */
113}
114
1c5113cf
SV
115static void __rds_conn_path_init(struct rds_connection *conn,
116 struct rds_conn_path *cp, bool is_outgoing)
117{
118 spin_lock_init(&cp->cp_lock);
119 cp->cp_next_tx_seq = 1;
120 init_waitqueue_head(&cp->cp_waitq);
121 INIT_LIST_HEAD(&cp->cp_send_queue);
122 INIT_LIST_HEAD(&cp->cp_retrans);
123
124 cp->cp_conn = conn;
125 atomic_set(&cp->cp_state, RDS_CONN_DOWN);
126 cp->cp_send_gen = 0;
127 /* cp_outgoing is per-path. So we can only set it here
128 * for the single-path transports.
129 */
130 if (!conn->c_trans->t_mp_capable)
131 cp->cp_outgoing = (is_outgoing ? 1 : 0);
132 cp->cp_reconnect_jiffies = 0;
133 INIT_DELAYED_WORK(&cp->cp_send_w, rds_send_worker);
134 INIT_DELAYED_WORK(&cp->cp_recv_w, rds_recv_worker);
135 INIT_DELAYED_WORK(&cp->cp_conn_w, rds_connect_worker);
136 INIT_WORK(&cp->cp_down_w, rds_shutdown_worker);
137 mutex_init(&cp->cp_cm_lock);
138 cp->cp_flags = 0;
139}
140
00e0f34c
AG
141/*
142 * There is only every one 'conn' for a given pair of addresses in the
143 * system at a time. They contain messages to be retransmitted and so
144 * span the lifetime of the actual underlying transport connections.
145 *
146 * For now they are not garbage collected once they're created. They
147 * are torn down as the module is removed, if ever.
148 */
d5a8ac28
SV
149static struct rds_connection *__rds_conn_create(struct net *net,
150 __be32 laddr, __be32 faddr,
00e0f34c
AG
151 struct rds_transport *trans, gfp_t gfp,
152 int is_outgoing)
153{
cb24405e 154 struct rds_connection *conn, *parent = NULL;
00e0f34c 155 struct hlist_head *head = rds_conn_bucket(laddr, faddr);
5adb5bc6 156 struct rds_transport *loop_trans;
00e0f34c 157 unsigned long flags;
5916e2c1 158 int ret, i;
00e0f34c 159
bcf50ef2 160 rcu_read_lock();
8f384c01 161 conn = rds_conn_lookup(net, head, laddr, faddr, trans);
f64f9e71 162 if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport &&
1789b2c0 163 laddr == faddr && !is_outgoing) {
00e0f34c
AG
164 /* This is a looped back IB connection, and we're
165 * called by the code handling the incoming connect.
166 * We need a second connection object into which we
167 * can stick the other QP. */
168 parent = conn;
169 conn = parent->c_passive;
170 }
bcf50ef2 171 rcu_read_unlock();
00e0f34c
AG
172 if (conn)
173 goto out;
174
05a178ec 175 conn = kmem_cache_zalloc(rds_conn_slab, gfp);
8690bfa1 176 if (!conn) {
00e0f34c
AG
177 conn = ERR_PTR(-ENOMEM);
178 goto out;
179 }
180
00e0f34c 181 INIT_HLIST_NODE(&conn->c_hash_node);
00e0f34c
AG
182 conn->c_laddr = laddr;
183 conn->c_faddr = faddr;
00e0f34c 184
1c5113cf 185 rds_conn_net_set(conn, net);
00e0f34c
AG
186
187 ret = rds_cong_get_maps(conn);
188 if (ret) {
189 kmem_cache_free(rds_conn_slab, conn);
190 conn = ERR_PTR(ret);
191 goto out;
192 }
193
194 /*
195 * This is where a connection becomes loopback. If *any* RDS sockets
196 * can bind to the destination address then we'd rather the messages
197 * flow through loopback rather than either transport.
198 */
d5a8ac28 199 loop_trans = rds_trans_get_preferred(net, faddr);
5adb5bc6
ZB
200 if (loop_trans) {
201 rds_trans_put(loop_trans);
00e0f34c
AG
202 conn->c_loopback = 1;
203 if (is_outgoing && trans->t_prefer_loopback) {
204 /* "outgoing" connection - and the transport
205 * says it wants the connection handled by the
206 * loopback transport. This is what TCP does.
207 */
208 trans = &rds_loop_transport;
209 }
210 }
211
212 conn->c_trans = trans;
213
5916e2c1
SV
214 init_waitqueue_head(&conn->c_hs_waitq);
215 for (i = 0; i < RDS_MPATH_WORKERS; i++) {
216 __rds_conn_path_init(conn, &conn->c_path[i],
217 is_outgoing);
218 conn->c_path[i].cp_index = i;
219 }
00e0f34c
AG
220 ret = trans->conn_alloc(conn, gfp);
221 if (ret) {
222 kmem_cache_free(rds_conn_slab, conn);
223 conn = ERR_PTR(ret);
224 goto out;
225 }
226
00e0f34c
AG
227 rdsdebug("allocated conn %p for %pI4 -> %pI4 over %s %s\n",
228 conn, &laddr, &faddr,
229 trans->t_name ? trans->t_name : "[unknown]",
230 is_outgoing ? "(outgoing)" : "");
231
cb24405e
AG
232 /*
233 * Since we ran without holding the conn lock, someone could
234 * have created the same conn (either normal or passive) in the
235 * interim. We check while holding the lock. If we won, we complete
236 * init and return our conn. If we lost, we rollback and return the
237 * other one.
238 */
00e0f34c 239 spin_lock_irqsave(&rds_conn_lock, flags);
cb24405e
AG
240 if (parent) {
241 /* Creating passive conn */
242 if (parent->c_passive) {
1c5113cf 243 trans->conn_free(conn->c_path[0].cp_transport_data);
cb24405e
AG
244 kmem_cache_free(rds_conn_slab, conn);
245 conn = parent->c_passive;
246 } else {
00e0f34c 247 parent->c_passive = conn;
cb24405e
AG
248 rds_cong_add_conn(conn);
249 rds_conn_count++;
250 }
00e0f34c 251 } else {
cb24405e
AG
252 /* Creating normal conn */
253 struct rds_connection *found;
254
3b20fc38 255 found = rds_conn_lookup(net, head, laddr, faddr, trans);
cb24405e 256 if (found) {
1c5113cf
SV
257 struct rds_conn_path *cp;
258 int i;
259
260 for (i = 0; i < RDS_MPATH_WORKERS; i++) {
261 cp = &conn->c_path[i];
02105b2c
SV
262 /* The ->conn_alloc invocation may have
263 * allocated resource for all paths, so all
264 * of them may have to be freed here.
265 */
266 if (cp->cp_transport_data)
267 trans->conn_free(cp->cp_transport_data);
1c5113cf 268 }
cb24405e
AG
269 kmem_cache_free(rds_conn_slab, conn);
270 conn = found;
271 } else {
3b20fc38 272 hlist_add_head_rcu(&conn->c_hash_node, head);
cb24405e
AG
273 rds_cong_add_conn(conn);
274 rds_conn_count++;
275 }
00e0f34c 276 }
00e0f34c
AG
277 spin_unlock_irqrestore(&rds_conn_lock, flags);
278
279out:
280 return conn;
281}
282
d5a8ac28
SV
283struct rds_connection *rds_conn_create(struct net *net,
284 __be32 laddr, __be32 faddr,
00e0f34c
AG
285 struct rds_transport *trans, gfp_t gfp)
286{
d5a8ac28 287 return __rds_conn_create(net, laddr, faddr, trans, gfp, 0);
00e0f34c 288}
616b757a 289EXPORT_SYMBOL_GPL(rds_conn_create);
00e0f34c 290
d5a8ac28
SV
291struct rds_connection *rds_conn_create_outgoing(struct net *net,
292 __be32 laddr, __be32 faddr,
00e0f34c
AG
293 struct rds_transport *trans, gfp_t gfp)
294{
d5a8ac28 295 return __rds_conn_create(net, laddr, faddr, trans, gfp, 1);
00e0f34c 296}
616b757a 297EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
00e0f34c 298
d769ef81 299void rds_conn_shutdown(struct rds_conn_path *cp)
2dc39357 300{
d769ef81
SV
301 struct rds_connection *conn = cp->cp_conn;
302
2dc39357 303 /* shut it down unless it's down already */
d769ef81 304 if (!rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_DOWN)) {
2dc39357
AG
305 /*
306 * Quiesce the connection mgmt handlers before we start tearing
307 * things down. We don't hold the mutex for the entire
308 * duration of the shutdown operation, else we may be
309 * deadlocking with the CM handler. Instead, the CM event
310 * handler is supposed to check for state DISCONNECTING
311 */
d769ef81
SV
312 mutex_lock(&cp->cp_cm_lock);
313 if (!rds_conn_path_transition(cp, RDS_CONN_UP,
314 RDS_CONN_DISCONNECTING) &&
315 !rds_conn_path_transition(cp, RDS_CONN_ERROR,
316 RDS_CONN_DISCONNECTING)) {
317 rds_conn_path_error(cp,
318 "shutdown called in state %d\n",
319 atomic_read(&cp->cp_state));
320 mutex_unlock(&cp->cp_cm_lock);
2dc39357
AG
321 return;
322 }
d769ef81 323 mutex_unlock(&cp->cp_cm_lock);
2dc39357 324
d769ef81
SV
325 wait_event(cp->cp_waitq,
326 !test_bit(RDS_IN_XMIT, &cp->cp_flags));
327 wait_event(cp->cp_waitq,
328 !test_bit(RDS_RECV_REFILL, &cp->cp_flags));
7e3f2952 329
226f7a7d 330 conn->c_trans->conn_path_shutdown(cp);
d769ef81 331 rds_conn_path_reset(cp);
2dc39357 332
d769ef81
SV
333 if (!rds_conn_path_transition(cp, RDS_CONN_DISCONNECTING,
334 RDS_CONN_DOWN)) {
2dc39357
AG
335 /* This can happen - eg when we're in the middle of tearing
336 * down the connection, and someone unloads the rds module.
337 * Quite reproduceable with loopback connections.
338 * Mostly harmless.
339 */
d769ef81
SV
340 rds_conn_path_error(cp, "%s: failed to transition "
341 "to state DOWN, current state "
342 "is %d\n", __func__,
343 atomic_read(&cp->cp_state));
2dc39357
AG
344 return;
345 }
346 }
347
348 /* Then reconnect if it's still live.
349 * The passive side of an IB loopback connection is never added
350 * to the conn hash, so we never trigger a reconnect on this
351 * conn - the reconnect is always triggered by the active peer. */
d769ef81 352 cancel_delayed_work_sync(&cp->cp_conn_w);
bcf50ef2
CM
353 rcu_read_lock();
354 if (!hlist_unhashed(&conn->c_hash_node)) {
355 rcu_read_unlock();
8315011a 356 rds_queue_reconnect(cp);
bcf50ef2
CM
357 } else {
358 rcu_read_unlock();
359 }
2dc39357
AG
360}
361
3ecc5693
SV
362/* destroy a single rds_conn_path. rds_conn_destroy() iterates over
363 * all paths using rds_conn_path_destroy()
364 */
365static void rds_conn_path_destroy(struct rds_conn_path *cp)
366{
367 struct rds_message *rm, *rtmp;
368
02105b2c
SV
369 if (!cp->cp_transport_data)
370 return;
371
3ecc5693
SV
372 rds_conn_path_drop(cp);
373 flush_work(&cp->cp_down_w);
374
375 /* make sure lingering queued work won't try to ref the conn */
376 cancel_delayed_work_sync(&cp->cp_send_w);
377 cancel_delayed_work_sync(&cp->cp_recv_w);
378
379 /* tear down queued messages */
380 list_for_each_entry_safe(rm, rtmp,
381 &cp->cp_send_queue,
382 m_conn_item) {
383 list_del_init(&rm->m_conn_item);
384 BUG_ON(!list_empty(&rm->m_sock_item));
385 rds_message_put(rm);
386 }
387 if (cp->cp_xmit_rm)
388 rds_message_put(cp->cp_xmit_rm);
389
390 cp->cp_conn->c_trans->conn_free(cp->cp_transport_data);
391}
392
2dc39357
AG
393/*
394 * Stop and free a connection.
ffcec0e1
ZB
395 *
396 * This can only be used in very limited circumstances. It assumes that once
397 * the conn has been shutdown that no one else is referencing the connection.
398 * We can only ensure this in the rmmod path in the current code.
2dc39357 399 */
00e0f34c
AG
400void rds_conn_destroy(struct rds_connection *conn)
401{
fe8ff6b5 402 unsigned long flags;
02105b2c
SV
403 int i;
404 struct rds_conn_path *cp;
00e0f34c
AG
405
406 rdsdebug("freeing conn %p for %pI4 -> "
407 "%pI4\n", conn, &conn->c_laddr,
408 &conn->c_faddr);
409
abf45439
CM
410 /* Ensure conn will not be scheduled for reconnect */
411 spin_lock_irq(&rds_conn_lock);
bcf50ef2 412 hlist_del_init_rcu(&conn->c_hash_node);
abf45439 413 spin_unlock_irq(&rds_conn_lock);
bcf50ef2
CM
414 synchronize_rcu();
415
ffcec0e1 416 /* shut the connection down */
02105b2c
SV
417 for (i = 0; i < RDS_MPATH_WORKERS; i++) {
418 cp = &conn->c_path[i];
419 rds_conn_path_destroy(cp);
420 BUG_ON(!list_empty(&cp->cp_retrans));
00e0f34c 421 }
00e0f34c
AG
422
423 /*
424 * The congestion maps aren't freed up here. They're
425 * freed by rds_cong_exit() after all the connections
426 * have been freed.
427 */
428 rds_cong_remove_conn(conn);
429
00e0f34c
AG
430 kmem_cache_free(rds_conn_slab, conn);
431
fe8ff6b5 432 spin_lock_irqsave(&rds_conn_lock, flags);
00e0f34c 433 rds_conn_count--;
fe8ff6b5 434 spin_unlock_irqrestore(&rds_conn_lock, flags);
00e0f34c 435}
616b757a 436EXPORT_SYMBOL_GPL(rds_conn_destroy);
00e0f34c
AG
437
438static void rds_conn_message_info(struct socket *sock, unsigned int len,
439 struct rds_info_iterator *iter,
440 struct rds_info_lengths *lens,
441 int want_send)
442{
443 struct hlist_head *head;
00e0f34c
AG
444 struct list_head *list;
445 struct rds_connection *conn;
446 struct rds_message *rm;
00e0f34c 447 unsigned int total = 0;
501dcccd 448 unsigned long flags;
00e0f34c 449 size_t i;
992c9ec5 450 int j;
00e0f34c
AG
451
452 len /= sizeof(struct rds_info_message);
453
bcf50ef2 454 rcu_read_lock();
00e0f34c
AG
455
456 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
457 i++, head++) {
b67bfe0d 458 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
992c9ec5
SV
459 struct rds_conn_path *cp;
460
461 for (j = 0; j < RDS_MPATH_WORKERS; j++) {
462 cp = &conn->c_path[j];
463 if (want_send)
464 list = &cp->cp_send_queue;
465 else
466 list = &cp->cp_retrans;
467
468 spin_lock_irqsave(&cp->cp_lock, flags);
469
470 /* XXX too lazy to maintain counts.. */
471 list_for_each_entry(rm, list, m_conn_item) {
472 total++;
473 if (total <= len)
474 rds_inc_info_copy(&rm->m_inc,
475 iter,
476 conn->c_laddr,
477 conn->c_faddr,
478 0);
479 }
480
481 spin_unlock_irqrestore(&cp->cp_lock, flags);
482 if (!conn->c_trans->t_mp_capable)
483 break;
00e0f34c 484 }
00e0f34c
AG
485 }
486 }
bcf50ef2 487 rcu_read_unlock();
00e0f34c
AG
488
489 lens->nr = total;
490 lens->each = sizeof(struct rds_info_message);
491}
492
493static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
494 struct rds_info_iterator *iter,
495 struct rds_info_lengths *lens)
496{
497 rds_conn_message_info(sock, len, iter, lens, 1);
498}
499
500static void rds_conn_message_info_retrans(struct socket *sock,
501 unsigned int len,
502 struct rds_info_iterator *iter,
503 struct rds_info_lengths *lens)
504{
505 rds_conn_message_info(sock, len, iter, lens, 0);
506}
507
508void rds_for_each_conn_info(struct socket *sock, unsigned int len,
509 struct rds_info_iterator *iter,
510 struct rds_info_lengths *lens,
511 int (*visitor)(struct rds_connection *, void *),
512 size_t item_len)
513{
514 uint64_t buffer[(item_len + 7) / 8];
515 struct hlist_head *head;
00e0f34c 516 struct rds_connection *conn;
00e0f34c
AG
517 size_t i;
518
bcf50ef2 519 rcu_read_lock();
00e0f34c
AG
520
521 lens->nr = 0;
522 lens->each = item_len;
523
524 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
525 i++, head++) {
b67bfe0d 526 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
00e0f34c
AG
527
528 /* XXX no c_lock usage.. */
529 if (!visitor(conn, buffer))
530 continue;
531
532 /* We copy as much as we can fit in the buffer,
533 * but we count all items so that the caller
534 * can resize the buffer. */
535 if (len >= item_len) {
536 rds_info_copy(iter, buffer, item_len);
537 len -= item_len;
538 }
539 lens->nr++;
540 }
541 }
bcf50ef2 542 rcu_read_unlock();
00e0f34c 543}
616b757a 544EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
00e0f34c 545
992c9ec5
SV
546void rds_walk_conn_path_info(struct socket *sock, unsigned int len,
547 struct rds_info_iterator *iter,
548 struct rds_info_lengths *lens,
549 int (*visitor)(struct rds_conn_path *, void *),
550 size_t item_len)
551{
552 u64 buffer[(item_len + 7) / 8];
553 struct hlist_head *head;
554 struct rds_connection *conn;
555 size_t i;
556 int j;
557
558 rcu_read_lock();
559
560 lens->nr = 0;
561 lens->each = item_len;
562
563 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
564 i++, head++) {
565 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
566 struct rds_conn_path *cp;
567
568 for (j = 0; j < RDS_MPATH_WORKERS; j++) {
569 cp = &conn->c_path[j];
570
571 /* XXX no cp_lock usage.. */
572 if (!visitor(cp, buffer))
573 continue;
574 if (!conn->c_trans->t_mp_capable)
575 break;
576 }
577
578 /* We copy as much as we can fit in the buffer,
579 * but we count all items so that the caller
580 * can resize the buffer.
581 */
582 if (len >= item_len) {
583 rds_info_copy(iter, buffer, item_len);
584 len -= item_len;
585 }
586 lens->nr++;
587 }
588 }
589 rcu_read_unlock();
590}
591
592static int rds_conn_info_visitor(struct rds_conn_path *cp, void *buffer)
00e0f34c
AG
593{
594 struct rds_info_connection *cinfo = buffer;
595
992c9ec5
SV
596 cinfo->next_tx_seq = cp->cp_next_tx_seq;
597 cinfo->next_rx_seq = cp->cp_next_rx_seq;
598 cinfo->laddr = cp->cp_conn->c_laddr;
599 cinfo->faddr = cp->cp_conn->c_faddr;
600 strncpy(cinfo->transport, cp->cp_conn->c_trans->t_name,
00e0f34c
AG
601 sizeof(cinfo->transport));
602 cinfo->flags = 0;
603
992c9ec5 604 rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags),
0f4b1c7e 605 SENDING);
00e0f34c
AG
606 /* XXX Future: return the state rather than these funky bits */
607 rds_conn_info_set(cinfo->flags,
992c9ec5 608 atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING,
00e0f34c
AG
609 CONNECTING);
610 rds_conn_info_set(cinfo->flags,
992c9ec5 611 atomic_read(&cp->cp_state) == RDS_CONN_UP,
00e0f34c
AG
612 CONNECTED);
613 return 1;
614}
615
616static void rds_conn_info(struct socket *sock, unsigned int len,
617 struct rds_info_iterator *iter,
618 struct rds_info_lengths *lens)
619{
992c9ec5 620 rds_walk_conn_path_info(sock, len, iter, lens,
00e0f34c
AG
621 rds_conn_info_visitor,
622 sizeof(struct rds_info_connection));
623}
624
ef87b7ea 625int rds_conn_init(void)
00e0f34c
AG
626{
627 rds_conn_slab = kmem_cache_create("rds_connection",
628 sizeof(struct rds_connection),
629 0, 0, NULL);
8690bfa1 630 if (!rds_conn_slab)
00e0f34c
AG
631 return -ENOMEM;
632
633 rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
634 rds_info_register_func(RDS_INFO_SEND_MESSAGES,
635 rds_conn_message_info_send);
636 rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
637 rds_conn_message_info_retrans);
638
639 return 0;
640}
641
642void rds_conn_exit(void)
643{
644 rds_loop_exit();
645
646 WARN_ON(!hlist_empty(rds_conn_hash));
647
648 kmem_cache_destroy(rds_conn_slab);
649
650 rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
651 rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
652 rds_conn_message_info_send);
653 rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
654 rds_conn_message_info_retrans);
655}
656
657/*
658 * Force a disconnect
659 */
0cb43965
SV
660void rds_conn_path_drop(struct rds_conn_path *cp)
661{
662 atomic_set(&cp->cp_state, RDS_CONN_ERROR);
663 queue_work(rds_wq, &cp->cp_down_w);
664}
665EXPORT_SYMBOL_GPL(rds_conn_path_drop);
666
00e0f34c
AG
667void rds_conn_drop(struct rds_connection *conn)
668{
5916e2c1 669 WARN_ON(conn->c_trans->t_mp_capable);
0cb43965 670 rds_conn_path_drop(&conn->c_path[0]);
00e0f34c 671}
616b757a 672EXPORT_SYMBOL_GPL(rds_conn_drop);
00e0f34c 673
f3c6808d
ZB
674/*
675 * If the connection is down, trigger a connect. We may have scheduled a
676 * delayed reconnect however - in this case we should not interfere.
677 */
3c0a5900
SV
678void rds_conn_path_connect_if_down(struct rds_conn_path *cp)
679{
680 if (rds_conn_path_state(cp) == RDS_CONN_DOWN &&
681 !test_and_set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags))
682 queue_delayed_work(rds_wq, &cp->cp_conn_w, 0);
683}
684
f3c6808d
ZB
685void rds_conn_connect_if_down(struct rds_connection *conn)
686{
3c0a5900
SV
687 WARN_ON(conn->c_trans->t_mp_capable);
688 rds_conn_path_connect_if_down(&conn->c_path[0]);
f3c6808d
ZB
689}
690EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
691
00e0f34c
AG
692/*
693 * An error occurred on the connection
694 */
695void
696__rds_conn_error(struct rds_connection *conn, const char *fmt, ...)
697{
698 va_list ap;
699
700 va_start(ap, fmt);
701 vprintk(fmt, ap);
702 va_end(ap);
703
704 rds_conn_drop(conn);
705}
fb1b3dc4
SV
706
707void
708__rds_conn_path_error(struct rds_conn_path *cp, const char *fmt, ...)
709{
710 va_list ap;
711
712 va_start(ap, fmt);
713 vprintk(fmt, ap);
714 va_end(ap);
715
716 rds_conn_path_drop(cp);
717}