blob: 75a1a37d64d34e5975bbce1c262454a87f2c483f [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>
Andy Grover00e0f342009-02-24 15:30:23 +000036#include <net/inet_hashtables.h>
37
38#include "rds.h"
39#include "loop.h"
Andy Grover00e0f342009-02-24 15:30:23 +000040
41#define RDS_CONNECTION_HASH_BITS 12
42#define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS)
43#define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1)
44
45/* converting this to RCU is a chore for another day.. */
46static DEFINE_SPINLOCK(rds_conn_lock);
47static unsigned long rds_conn_count;
48static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES];
49static struct kmem_cache *rds_conn_slab;
50
51static struct hlist_head *rds_conn_bucket(__be32 laddr, __be32 faddr)
52{
53 /* Pass NULL, don't need struct net for hash */
54 unsigned long hash = inet_ehashfn(NULL,
55 be32_to_cpu(laddr), 0,
56 be32_to_cpu(faddr), 0);
57 return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
58}
59
60#define rds_conn_info_set(var, test, suffix) do { \
61 if (test) \
62 var |= RDS_INFO_CONNECTION_FLAG_##suffix; \
63} while (0)
64
Chris Masonbcf50ef2010-05-11 15:15:15 -070065/* rcu read lock must be held or the connection spinlock */
Andy Grover00e0f342009-02-24 15:30:23 +000066static struct rds_connection *rds_conn_lookup(struct hlist_head *head,
67 __be32 laddr, __be32 faddr,
68 struct rds_transport *trans)
69{
70 struct rds_connection *conn, *ret = NULL;
71 struct hlist_node *pos;
72
Chris Masonbcf50ef2010-05-11 15:15:15 -070073 hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +000074 if (conn->c_faddr == faddr && conn->c_laddr == laddr &&
75 conn->c_trans == trans) {
76 ret = conn;
77 break;
78 }
79 }
80 rdsdebug("returning conn %p for %pI4 -> %pI4\n", ret,
81 &laddr, &faddr);
82 return ret;
83}
84
85/*
86 * This is called by transports as they're bringing down a connection.
87 * It clears partial message state so that the transport can start sending
88 * and receiving over this connection again in the future. It is up to
89 * the transport to have serialized this call with its send and recv.
90 */
91void rds_conn_reset(struct rds_connection *conn)
92{
93 rdsdebug("connection %pI4 to %pI4 reset\n",
94 &conn->c_laddr, &conn->c_faddr);
95
96 rds_stats_inc(s_conn_reset);
97 rds_send_reset(conn);
98 conn->c_flags = 0;
99
100 /* Do not clear next_rx_seq here, else we cannot distinguish
101 * retransmitted packets from new packets, and will hand all
102 * of them to the application. That is not consistent with the
103 * reliability guarantees of RDS. */
104}
105
106/*
107 * There is only every one 'conn' for a given pair of addresses in the
108 * system at a time. They contain messages to be retransmitted and so
109 * span the lifetime of the actual underlying transport connections.
110 *
111 * For now they are not garbage collected once they're created. They
112 * are torn down as the module is removed, if ever.
113 */
114static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
115 struct rds_transport *trans, gfp_t gfp,
116 int is_outgoing)
117{
Andy Grovercb244052009-07-17 13:13:36 +0000118 struct rds_connection *conn, *parent = NULL;
Andy Grover00e0f342009-02-24 15:30:23 +0000119 struct hlist_head *head = rds_conn_bucket(laddr, faddr);
120 unsigned long flags;
121 int ret;
122
Chris Masonbcf50ef2010-05-11 15:15:15 -0700123 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000124 conn = rds_conn_lookup(head, laddr, faddr, trans);
Joe Perchesf64f9e72009-11-29 16:55:45 -0800125 if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport &&
126 !is_outgoing) {
Andy Grover00e0f342009-02-24 15:30:23 +0000127 /* This is a looped back IB connection, and we're
128 * called by the code handling the incoming connect.
129 * We need a second connection object into which we
130 * can stick the other QP. */
131 parent = conn;
132 conn = parent->c_passive;
133 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700134 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000135 if (conn)
136 goto out;
137
Wei Yongjun05a178e2009-04-09 14:09:44 +0000138 conn = kmem_cache_zalloc(rds_conn_slab, gfp);
Andy Grover8690bfa2010-01-12 11:56:44 -0800139 if (!conn) {
Andy Grover00e0f342009-02-24 15:30:23 +0000140 conn = ERR_PTR(-ENOMEM);
141 goto out;
142 }
143
Andy Grover00e0f342009-02-24 15:30:23 +0000144 INIT_HLIST_NODE(&conn->c_hash_node);
Andy Grover00e0f342009-02-24 15:30:23 +0000145 conn->c_laddr = laddr;
146 conn->c_faddr = faddr;
147 spin_lock_init(&conn->c_lock);
148 conn->c_next_tx_seq = 1;
149
Zach Brown0f4b1c72010-06-04 14:41:41 -0700150 init_waitqueue_head(&conn->c_waitq);
Andy Grover00e0f342009-02-24 15:30:23 +0000151 INIT_LIST_HEAD(&conn->c_send_queue);
152 INIT_LIST_HEAD(&conn->c_retrans);
153
154 ret = rds_cong_get_maps(conn);
155 if (ret) {
156 kmem_cache_free(rds_conn_slab, conn);
157 conn = ERR_PTR(ret);
158 goto out;
159 }
160
161 /*
162 * This is where a connection becomes loopback. If *any* RDS sockets
163 * can bind to the destination address then we'd rather the messages
164 * flow through loopback rather than either transport.
165 */
166 if (rds_trans_get_preferred(faddr)) {
167 conn->c_loopback = 1;
168 if (is_outgoing && trans->t_prefer_loopback) {
169 /* "outgoing" connection - and the transport
170 * says it wants the connection handled by the
171 * loopback transport. This is what TCP does.
172 */
173 trans = &rds_loop_transport;
174 }
175 }
176
177 conn->c_trans = trans;
178
179 ret = trans->conn_alloc(conn, gfp);
180 if (ret) {
181 kmem_cache_free(rds_conn_slab, conn);
182 conn = ERR_PTR(ret);
183 goto out;
184 }
185
186 atomic_set(&conn->c_state, RDS_CONN_DOWN);
187 conn->c_reconnect_jiffies = 0;
188 INIT_DELAYED_WORK(&conn->c_send_w, rds_send_worker);
189 INIT_DELAYED_WORK(&conn->c_recv_w, rds_recv_worker);
190 INIT_DELAYED_WORK(&conn->c_conn_w, rds_connect_worker);
191 INIT_WORK(&conn->c_down_w, rds_shutdown_worker);
192 mutex_init(&conn->c_cm_lock);
193 conn->c_flags = 0;
194
195 rdsdebug("allocated conn %p for %pI4 -> %pI4 over %s %s\n",
196 conn, &laddr, &faddr,
197 trans->t_name ? trans->t_name : "[unknown]",
198 is_outgoing ? "(outgoing)" : "");
199
Andy Grovercb244052009-07-17 13:13:36 +0000200 /*
201 * Since we ran without holding the conn lock, someone could
202 * have created the same conn (either normal or passive) in the
203 * interim. We check while holding the lock. If we won, we complete
204 * init and return our conn. If we lost, we rollback and return the
205 * other one.
206 */
Andy Grover00e0f342009-02-24 15:30:23 +0000207 spin_lock_irqsave(&rds_conn_lock, flags);
Andy Grovercb244052009-07-17 13:13:36 +0000208 if (parent) {
209 /* Creating passive conn */
210 if (parent->c_passive) {
211 trans->conn_free(conn->c_transport_data);
212 kmem_cache_free(rds_conn_slab, conn);
213 conn = parent->c_passive;
214 } else {
Andy Grover00e0f342009-02-24 15:30:23 +0000215 parent->c_passive = conn;
Andy Grovercb244052009-07-17 13:13:36 +0000216 rds_cong_add_conn(conn);
217 rds_conn_count++;
218 }
Andy Grover00e0f342009-02-24 15:30:23 +0000219 } else {
Andy Grovercb244052009-07-17 13:13:36 +0000220 /* Creating normal conn */
221 struct rds_connection *found;
Andy Grover00e0f342009-02-24 15:30:23 +0000222
Andy Grovercb244052009-07-17 13:13:36 +0000223 found = rds_conn_lookup(head, laddr, faddr, trans);
224 if (found) {
225 trans->conn_free(conn->c_transport_data);
226 kmem_cache_free(rds_conn_slab, conn);
227 conn = found;
228 } else {
Chris Masonbcf50ef2010-05-11 15:15:15 -0700229 hlist_add_head_rcu(&conn->c_hash_node, head);
Andy Grovercb244052009-07-17 13:13:36 +0000230 rds_cong_add_conn(conn);
231 rds_conn_count++;
232 }
233 }
Andy Grover00e0f342009-02-24 15:30:23 +0000234 spin_unlock_irqrestore(&rds_conn_lock, flags);
235
236out:
237 return conn;
238}
239
240struct rds_connection *rds_conn_create(__be32 laddr, __be32 faddr,
241 struct rds_transport *trans, gfp_t gfp)
242{
243 return __rds_conn_create(laddr, faddr, trans, gfp, 0);
244}
Andy Grover616b7572009-08-21 12:28:32 +0000245EXPORT_SYMBOL_GPL(rds_conn_create);
Andy Grover00e0f342009-02-24 15:30:23 +0000246
247struct rds_connection *rds_conn_create_outgoing(__be32 laddr, __be32 faddr,
248 struct rds_transport *trans, gfp_t gfp)
249{
250 return __rds_conn_create(laddr, faddr, trans, gfp, 1);
251}
Andy Grover616b7572009-08-21 12:28:32 +0000252EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
Andy Grover00e0f342009-02-24 15:30:23 +0000253
Andy Grover2dc39352010-06-11 13:49:13 -0700254void rds_conn_shutdown(struct rds_connection *conn)
255{
256 /* shut it down unless it's down already */
257 if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_DOWN)) {
258 /*
259 * Quiesce the connection mgmt handlers before we start tearing
260 * things down. We don't hold the mutex for the entire
261 * duration of the shutdown operation, else we may be
262 * deadlocking with the CM handler. Instead, the CM event
263 * handler is supposed to check for state DISCONNECTING
264 */
265 mutex_lock(&conn->c_cm_lock);
266 if (!rds_conn_transition(conn, RDS_CONN_UP, RDS_CONN_DISCONNECTING)
267 && !rds_conn_transition(conn, RDS_CONN_ERROR, RDS_CONN_DISCONNECTING)) {
268 rds_conn_error(conn, "shutdown called in state %d\n",
269 atomic_read(&conn->c_state));
270 mutex_unlock(&conn->c_cm_lock);
271 return;
272 }
273 mutex_unlock(&conn->c_cm_lock);
274
Zach Brown0f4b1c72010-06-04 14:41:41 -0700275 wait_event(conn->c_waitq,
276 !test_bit(RDS_IN_XMIT, &conn->c_flags));
Chris Mason7e3f2952010-05-11 15:11:11 -0700277
Andy Grover2dc39352010-06-11 13:49:13 -0700278 conn->c_trans->conn_shutdown(conn);
279 rds_conn_reset(conn);
Andy Grover2dc39352010-06-11 13:49:13 -0700280
281 if (!rds_conn_transition(conn, RDS_CONN_DISCONNECTING, RDS_CONN_DOWN)) {
282 /* This can happen - eg when we're in the middle of tearing
283 * down the connection, and someone unloads the rds module.
284 * Quite reproduceable with loopback connections.
285 * Mostly harmless.
286 */
287 rds_conn_error(conn,
288 "%s: failed to transition to state DOWN, "
289 "current state is %d\n",
290 __func__,
291 atomic_read(&conn->c_state));
292 return;
293 }
294 }
295
296 /* Then reconnect if it's still live.
297 * The passive side of an IB loopback connection is never added
298 * to the conn hash, so we never trigger a reconnect on this
299 * conn - the reconnect is always triggered by the active peer. */
300 cancel_delayed_work_sync(&conn->c_conn_w);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700301 rcu_read_lock();
302 if (!hlist_unhashed(&conn->c_hash_node)) {
303 rcu_read_unlock();
Andy Grover2dc39352010-06-11 13:49:13 -0700304 rds_queue_reconnect(conn);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700305 } else {
306 rcu_read_unlock();
307 }
Andy Grover2dc39352010-06-11 13:49:13 -0700308}
309
310/*
311 * Stop and free a connection.
312 */
Andy Grover00e0f342009-02-24 15:30:23 +0000313void rds_conn_destroy(struct rds_connection *conn)
314{
315 struct rds_message *rm, *rtmp;
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700316 unsigned long flags;
Andy Grover00e0f342009-02-24 15:30:23 +0000317
318 rdsdebug("freeing conn %p for %pI4 -> "
319 "%pI4\n", conn, &conn->c_laddr,
320 &conn->c_faddr);
321
Chris Masonabf45432010-05-11 15:14:52 -0700322 /* Ensure conn will not be scheduled for reconnect */
323 spin_lock_irq(&rds_conn_lock);
Chris Masonbcf50ef2010-05-11 15:15:15 -0700324 hlist_del_init_rcu(&conn->c_hash_node);
Chris Masonabf45432010-05-11 15:14:52 -0700325 spin_unlock_irq(&rds_conn_lock);
Andy Grover00e0f342009-02-24 15:30:23 +0000326
Chris Masonbcf50ef2010-05-11 15:15:15 -0700327 synchronize_rcu();
328
329 rds_conn_shutdown(conn);
Andy Grover00e0f342009-02-24 15:30:23 +0000330
331 /* tear down queued messages */
332 list_for_each_entry_safe(rm, rtmp,
333 &conn->c_send_queue,
334 m_conn_item) {
335 list_del_init(&rm->m_conn_item);
336 BUG_ON(!list_empty(&rm->m_sock_item));
337 rds_message_put(rm);
338 }
339 if (conn->c_xmit_rm)
340 rds_message_put(conn->c_xmit_rm);
341
342 conn->c_trans->conn_free(conn->c_transport_data);
343
344 /*
345 * The congestion maps aren't freed up here. They're
346 * freed by rds_cong_exit() after all the connections
347 * have been freed.
348 */
349 rds_cong_remove_conn(conn);
350
351 BUG_ON(!list_empty(&conn->c_retrans));
352 kmem_cache_free(rds_conn_slab, conn);
353
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700354 spin_lock_irqsave(&rds_conn_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000355 rds_conn_count--;
Zach Brownfe8ff6b2010-07-23 10:30:45 -0700356 spin_unlock_irqrestore(&rds_conn_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000357}
Andy Grover616b7572009-08-21 12:28:32 +0000358EXPORT_SYMBOL_GPL(rds_conn_destroy);
Andy Grover00e0f342009-02-24 15:30:23 +0000359
360static void rds_conn_message_info(struct socket *sock, unsigned int len,
361 struct rds_info_iterator *iter,
362 struct rds_info_lengths *lens,
363 int want_send)
364{
365 struct hlist_head *head;
366 struct hlist_node *pos;
367 struct list_head *list;
368 struct rds_connection *conn;
369 struct rds_message *rm;
Andy Grover00e0f342009-02-24 15:30:23 +0000370 unsigned int total = 0;
Zach Brown501dccc2010-06-04 14:25:27 -0700371 unsigned long flags;
Andy Grover00e0f342009-02-24 15:30:23 +0000372 size_t i;
373
374 len /= sizeof(struct rds_info_message);
375
Chris Masonbcf50ef2010-05-11 15:15:15 -0700376 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000377
378 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
379 i++, head++) {
Chris Masonbcf50ef2010-05-11 15:15:15 -0700380 hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +0000381 if (want_send)
382 list = &conn->c_send_queue;
383 else
384 list = &conn->c_retrans;
385
Zach Brown501dccc2010-06-04 14:25:27 -0700386 spin_lock_irqsave(&conn->c_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000387
388 /* XXX too lazy to maintain counts.. */
389 list_for_each_entry(rm, list, m_conn_item) {
390 total++;
391 if (total <= len)
392 rds_inc_info_copy(&rm->m_inc, iter,
393 conn->c_laddr,
394 conn->c_faddr, 0);
395 }
396
Zach Brown501dccc2010-06-04 14:25:27 -0700397 spin_unlock_irqrestore(&conn->c_lock, flags);
Andy Grover00e0f342009-02-24 15:30:23 +0000398 }
399 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700400 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000401
402 lens->nr = total;
403 lens->each = sizeof(struct rds_info_message);
404}
405
406static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
407 struct rds_info_iterator *iter,
408 struct rds_info_lengths *lens)
409{
410 rds_conn_message_info(sock, len, iter, lens, 1);
411}
412
413static void rds_conn_message_info_retrans(struct socket *sock,
414 unsigned int len,
415 struct rds_info_iterator *iter,
416 struct rds_info_lengths *lens)
417{
418 rds_conn_message_info(sock, len, iter, lens, 0);
419}
420
421void rds_for_each_conn_info(struct socket *sock, unsigned int len,
422 struct rds_info_iterator *iter,
423 struct rds_info_lengths *lens,
424 int (*visitor)(struct rds_connection *, void *),
425 size_t item_len)
426{
427 uint64_t buffer[(item_len + 7) / 8];
428 struct hlist_head *head;
429 struct hlist_node *pos;
Andy Grover00e0f342009-02-24 15:30:23 +0000430 struct rds_connection *conn;
Andy Grover00e0f342009-02-24 15:30:23 +0000431 size_t i;
432
Chris Masonbcf50ef2010-05-11 15:15:15 -0700433 rcu_read_lock();
Andy Grover00e0f342009-02-24 15:30:23 +0000434
435 lens->nr = 0;
436 lens->each = item_len;
437
438 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
439 i++, head++) {
Chris Masonbcf50ef2010-05-11 15:15:15 -0700440 hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
Andy Grover00e0f342009-02-24 15:30:23 +0000441
442 /* XXX no c_lock usage.. */
443 if (!visitor(conn, buffer))
444 continue;
445
446 /* We copy as much as we can fit in the buffer,
447 * but we count all items so that the caller
448 * can resize the buffer. */
449 if (len >= item_len) {
450 rds_info_copy(iter, buffer, item_len);
451 len -= item_len;
452 }
453 lens->nr++;
454 }
455 }
Chris Masonbcf50ef2010-05-11 15:15:15 -0700456 rcu_read_unlock();
Andy Grover00e0f342009-02-24 15:30:23 +0000457}
Andy Grover616b7572009-08-21 12:28:32 +0000458EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
Andy Grover00e0f342009-02-24 15:30:23 +0000459
460static int rds_conn_info_visitor(struct rds_connection *conn,
461 void *buffer)
462{
463 struct rds_info_connection *cinfo = buffer;
464
465 cinfo->next_tx_seq = conn->c_next_tx_seq;
466 cinfo->next_rx_seq = conn->c_next_rx_seq;
467 cinfo->laddr = conn->c_laddr;
468 cinfo->faddr = conn->c_faddr;
469 strncpy(cinfo->transport, conn->c_trans->t_name,
470 sizeof(cinfo->transport));
471 cinfo->flags = 0;
472
Zach Brown0f4b1c72010-06-04 14:41:41 -0700473 rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &conn->c_flags),
474 SENDING);
Andy Grover00e0f342009-02-24 15:30:23 +0000475 /* XXX Future: return the state rather than these funky bits */
476 rds_conn_info_set(cinfo->flags,
477 atomic_read(&conn->c_state) == RDS_CONN_CONNECTING,
478 CONNECTING);
479 rds_conn_info_set(cinfo->flags,
480 atomic_read(&conn->c_state) == RDS_CONN_UP,
481 CONNECTED);
482 return 1;
483}
484
485static void rds_conn_info(struct socket *sock, unsigned int len,
486 struct rds_info_iterator *iter,
487 struct rds_info_lengths *lens)
488{
489 rds_for_each_conn_info(sock, len, iter, lens,
490 rds_conn_info_visitor,
491 sizeof(struct rds_info_connection));
492}
493
Zach Brownef87b7e2010-07-09 12:26:20 -0700494int rds_conn_init(void)
Andy Grover00e0f342009-02-24 15:30:23 +0000495{
496 rds_conn_slab = kmem_cache_create("rds_connection",
497 sizeof(struct rds_connection),
498 0, 0, NULL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800499 if (!rds_conn_slab)
Andy Grover00e0f342009-02-24 15:30:23 +0000500 return -ENOMEM;
501
502 rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
503 rds_info_register_func(RDS_INFO_SEND_MESSAGES,
504 rds_conn_message_info_send);
505 rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
506 rds_conn_message_info_retrans);
507
508 return 0;
509}
510
511void rds_conn_exit(void)
512{
513 rds_loop_exit();
514
515 WARN_ON(!hlist_empty(rds_conn_hash));
516
517 kmem_cache_destroy(rds_conn_slab);
518
519 rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
520 rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
521 rds_conn_message_info_send);
522 rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
523 rds_conn_message_info_retrans);
524}
525
526/*
527 * Force a disconnect
528 */
529void rds_conn_drop(struct rds_connection *conn)
530{
531 atomic_set(&conn->c_state, RDS_CONN_ERROR);
532 queue_work(rds_wq, &conn->c_down_w);
533}
Andy Grover616b7572009-08-21 12:28:32 +0000534EXPORT_SYMBOL_GPL(rds_conn_drop);
Andy Grover00e0f342009-02-24 15:30:23 +0000535
536/*
Zach Brownf3c68082010-05-24 13:14:36 -0700537 * If the connection is down, trigger a connect. We may have scheduled a
538 * delayed reconnect however - in this case we should not interfere.
539 */
540void rds_conn_connect_if_down(struct rds_connection *conn)
541{
542 if (rds_conn_state(conn) == RDS_CONN_DOWN &&
543 !test_and_set_bit(RDS_RECONNECT_PENDING, &conn->c_flags))
544 queue_delayed_work(rds_wq, &conn->c_conn_w, 0);
545}
546EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
547
548/*
Andy Grover00e0f342009-02-24 15:30:23 +0000549 * An error occurred on the connection
550 */
551void
552__rds_conn_error(struct rds_connection *conn, const char *fmt, ...)
553{
554 va_list ap;
555
556 va_start(ap, fmt);
557 vprintk(fmt, ap);
558 va_end(ap);
559
560 rds_conn_drop(conn);
561}