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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>
35#include <linux/slab.h>
36#include <linux/export.h>
37#include <net/inet_hashtables.h>
38
39#include "rds.h"
40#include "loop.h"
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{
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
60 /* Pass NULL, don't need struct net for hash */
61 hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
62 be32_to_cpu(faddr), 0,
63 rds_hash_secret);
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
72/* rcu read lock must be held or the connection spinlock */
73static struct rds_connection *rds_conn_lookup(struct net *net,
74 struct hlist_head *head,
75 __be32 laddr, __be32 faddr,
76 struct rds_transport *trans)
77{
78 struct rds_connection *conn, *ret = NULL;
79
80 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
81 if (conn->c_faddr == faddr && conn->c_laddr == laddr &&
82 conn->c_trans == trans && net == rds_conn_net(conn)) {
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 */
98static void rds_conn_reset(struct rds_connection *conn)
99{
100 rdsdebug("connection %pI4 to %pI4 reset\n",
101 &conn->c_laddr, &conn->c_faddr);
102
103 rds_stats_inc(s_conn_reset);
104 rds_send_reset(conn);
105 conn->c_flags = 0;
106
107 /* Do not clear next_rx_seq here, else we cannot distinguish
108 * retransmitted packets from new packets, and will hand all
109 * of them to the application. That is not consistent with the
110 * reliability guarantees of RDS. */
111}
112
113/*
114 * There is only every one 'conn' for a given pair of addresses in the
115 * system at a time. They contain messages to be retransmitted and so
116 * span the lifetime of the actual underlying transport connections.
117 *
118 * For now they are not garbage collected once they're created. They
119 * are torn down as the module is removed, if ever.
120 */
121static struct rds_connection *__rds_conn_create(struct net *net,
122 __be32 laddr, __be32 faddr,
123 struct rds_transport *trans, gfp_t gfp,
124 int is_outgoing)
125{
126 struct rds_connection *conn, *parent = NULL;
127 struct hlist_head *head = rds_conn_bucket(laddr, faddr);
128 struct rds_transport *loop_trans;
129 unsigned long flags;
130 int ret;
131
132 rcu_read_lock();
133 conn = rds_conn_lookup(net, head, laddr, faddr, trans);
134 if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport &&
135 laddr == faddr && !is_outgoing) {
136 /* This is a looped back IB connection, and we're
137 * called by the code handling the incoming connect.
138 * We need a second connection object into which we
139 * can stick the other QP. */
140 parent = conn;
141 conn = parent->c_passive;
142 }
143 rcu_read_unlock();
144 if (conn)
145 goto out;
146
147 conn = kmem_cache_zalloc(rds_conn_slab, gfp);
148 if (!conn) {
149 conn = ERR_PTR(-ENOMEM);
150 goto out;
151 }
152
153 INIT_HLIST_NODE(&conn->c_hash_node);
154 conn->c_laddr = laddr;
155 conn->c_faddr = faddr;
156 spin_lock_init(&conn->c_lock);
157 conn->c_next_tx_seq = 1;
158 rds_conn_net_set(conn, net);
159
160 init_waitqueue_head(&conn->c_waitq);
161 INIT_LIST_HEAD(&conn->c_send_queue);
162 INIT_LIST_HEAD(&conn->c_retrans);
163
164 ret = rds_cong_get_maps(conn);
165 if (ret) {
166 kmem_cache_free(rds_conn_slab, conn);
167 conn = ERR_PTR(ret);
168 goto out;
169 }
170
171 /*
172 * This is where a connection becomes loopback. If *any* RDS sockets
173 * can bind to the destination address then we'd rather the messages
174 * flow through loopback rather than either transport.
175 */
176 loop_trans = rds_trans_get_preferred(net, faddr);
177 if (loop_trans) {
178 rds_trans_put(loop_trans);
179 conn->c_loopback = 1;
180 if (is_outgoing && trans->t_prefer_loopback) {
181 /* "outgoing" connection - and the transport
182 * says it wants the connection handled by the
183 * loopback transport. This is what TCP does.
184 */
185 trans = &rds_loop_transport;
186 }
187 }
188
189 conn->c_trans = trans;
190
191 ret = trans->conn_alloc(conn, gfp);
192 if (ret) {
193 kmem_cache_free(rds_conn_slab, conn);
194 conn = ERR_PTR(ret);
195 goto out;
196 }
197
198 atomic_set(&conn->c_state, RDS_CONN_DOWN);
199 conn->c_send_gen = 0;
200 conn->c_outgoing = (is_outgoing ? 1 : 0);
201 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
214 /*
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 */
221 spin_lock_irqsave(&rds_conn_lock, flags);
222 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 {
229 parent->c_passive = conn;
230 rds_cong_add_conn(conn);
231 rds_conn_count++;
232 }
233 } else {
234 /* Creating normal conn */
235 struct rds_connection *found;
236
237 found = rds_conn_lookup(net, head, laddr, faddr, trans);
238 if (found) {
239 trans->conn_free(conn->c_transport_data);
240 kmem_cache_free(rds_conn_slab, conn);
241 conn = found;
242 } else {
243 hlist_add_head_rcu(&conn->c_hash_node, head);
244 rds_cong_add_conn(conn);
245 rds_conn_count++;
246 }
247 }
248 spin_unlock_irqrestore(&rds_conn_lock, flags);
249
250out:
251 return conn;
252}
253
254struct rds_connection *rds_conn_create(struct net *net,
255 __be32 laddr, __be32 faddr,
256 struct rds_transport *trans, gfp_t gfp)
257{
258 return __rds_conn_create(net, laddr, faddr, trans, gfp, 0);
259}
260EXPORT_SYMBOL_GPL(rds_conn_create);
261
262struct rds_connection *rds_conn_create_outgoing(struct net *net,
263 __be32 laddr, __be32 faddr,
264 struct rds_transport *trans, gfp_t gfp)
265{
266 return __rds_conn_create(net, laddr, faddr, trans, gfp, 1);
267}
268EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
269
270void rds_conn_shutdown(struct rds_connection *conn)
271{
272 /* shut it down unless it's down already */
273 if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_DOWN)) {
274 /*
275 * Quiesce the connection mgmt handlers before we start tearing
276 * things down. We don't hold the mutex for the entire
277 * duration of the shutdown operation, else we may be
278 * deadlocking with the CM handler. Instead, the CM event
279 * handler is supposed to check for state DISCONNECTING
280 */
281 mutex_lock(&conn->c_cm_lock);
282 if (!rds_conn_transition(conn, RDS_CONN_UP, RDS_CONN_DISCONNECTING)
283 && !rds_conn_transition(conn, RDS_CONN_ERROR, RDS_CONN_DISCONNECTING)) {
284 rds_conn_error(conn, "shutdown called in state %d\n",
285 atomic_read(&conn->c_state));
286 mutex_unlock(&conn->c_cm_lock);
287 return;
288 }
289 mutex_unlock(&conn->c_cm_lock);
290
291 wait_event(conn->c_waitq,
292 !test_bit(RDS_IN_XMIT, &conn->c_flags));
293 wait_event(conn->c_waitq,
294 !test_bit(RDS_RECV_REFILL, &conn->c_flags));
295
296 conn->c_trans->conn_shutdown(conn);
297 rds_conn_reset(conn);
298
299 if (!rds_conn_transition(conn, RDS_CONN_DISCONNECTING, RDS_CONN_DOWN)) {
300 /* This can happen - eg when we're in the middle of tearing
301 * down the connection, and someone unloads the rds module.
302 * Quite reproduceable with loopback connections.
303 * Mostly harmless.
304 */
305 rds_conn_error(conn,
306 "%s: failed to transition to state DOWN, "
307 "current state is %d\n",
308 __func__,
309 atomic_read(&conn->c_state));
310 return;
311 }
312 }
313
314 /* Then reconnect if it's still live.
315 * The passive side of an IB loopback connection is never added
316 * to the conn hash, so we never trigger a reconnect on this
317 * conn - the reconnect is always triggered by the active peer. */
318 cancel_delayed_work_sync(&conn->c_conn_w);
319 rcu_read_lock();
320 if (!hlist_unhashed(&conn->c_hash_node)) {
321 rcu_read_unlock();
322 if (conn->c_trans->t_type != RDS_TRANS_TCP ||
323 conn->c_outgoing == 1)
324 rds_queue_reconnect(conn);
325 } else {
326 rcu_read_unlock();
327 }
328}
329
330/*
331 * Stop and free a connection.
332 *
333 * This can only be used in very limited circumstances. It assumes that once
334 * the conn has been shutdown that no one else is referencing the connection.
335 * We can only ensure this in the rmmod path in the current code.
336 */
337void rds_conn_destroy(struct rds_connection *conn)
338{
339 struct rds_message *rm, *rtmp;
340 unsigned long flags;
341
342 rdsdebug("freeing conn %p for %pI4 -> "
343 "%pI4\n", conn, &conn->c_laddr,
344 &conn->c_faddr);
345
346 /* Ensure conn will not be scheduled for reconnect */
347 spin_lock_irq(&rds_conn_lock);
348 hlist_del_init_rcu(&conn->c_hash_node);
349 spin_unlock_irq(&rds_conn_lock);
350 synchronize_rcu();
351
352 /* shut the connection down */
353 rds_conn_drop(conn);
354 flush_work(&conn->c_down_w);
355
356 /* make sure lingering queued work won't try to ref the conn */
357 cancel_delayed_work_sync(&conn->c_send_w);
358 cancel_delayed_work_sync(&conn->c_recv_w);
359
360 /* tear down queued messages */
361 list_for_each_entry_safe(rm, rtmp,
362 &conn->c_send_queue,
363 m_conn_item) {
364 list_del_init(&rm->m_conn_item);
365 BUG_ON(!list_empty(&rm->m_sock_item));
366 rds_message_put(rm);
367 }
368 if (conn->c_xmit_rm)
369 rds_message_put(conn->c_xmit_rm);
370
371 conn->c_trans->conn_free(conn->c_transport_data);
372
373 /*
374 * The congestion maps aren't freed up here. They're
375 * freed by rds_cong_exit() after all the connections
376 * have been freed.
377 */
378 rds_cong_remove_conn(conn);
379
380 BUG_ON(!list_empty(&conn->c_retrans));
381 kmem_cache_free(rds_conn_slab, conn);
382
383 spin_lock_irqsave(&rds_conn_lock, flags);
384 rds_conn_count--;
385 spin_unlock_irqrestore(&rds_conn_lock, flags);
386}
387EXPORT_SYMBOL_GPL(rds_conn_destroy);
388
389static void rds_conn_message_info(struct socket *sock, unsigned int len,
390 struct rds_info_iterator *iter,
391 struct rds_info_lengths *lens,
392 int want_send)
393{
394 struct hlist_head *head;
395 struct list_head *list;
396 struct rds_connection *conn;
397 struct rds_message *rm;
398 unsigned int total = 0;
399 unsigned long flags;
400 size_t i;
401
402 len /= sizeof(struct rds_info_message);
403
404 rcu_read_lock();
405
406 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
407 i++, head++) {
408 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
409 if (want_send)
410 list = &conn->c_send_queue;
411 else
412 list = &conn->c_retrans;
413
414 spin_lock_irqsave(&conn->c_lock, flags);
415
416 /* XXX too lazy to maintain counts.. */
417 list_for_each_entry(rm, list, m_conn_item) {
418 total++;
419 if (total <= len)
420 rds_inc_info_copy(&rm->m_inc, iter,
421 conn->c_laddr,
422 conn->c_faddr, 0);
423 }
424
425 spin_unlock_irqrestore(&conn->c_lock, flags);
426 }
427 }
428 rcu_read_unlock();
429
430 lens->nr = total;
431 lens->each = sizeof(struct rds_info_message);
432}
433
434static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
435 struct rds_info_iterator *iter,
436 struct rds_info_lengths *lens)
437{
438 rds_conn_message_info(sock, len, iter, lens, 1);
439}
440
441static void rds_conn_message_info_retrans(struct socket *sock,
442 unsigned int len,
443 struct rds_info_iterator *iter,
444 struct rds_info_lengths *lens)
445{
446 rds_conn_message_info(sock, len, iter, lens, 0);
447}
448
449void rds_for_each_conn_info(struct socket *sock, unsigned int len,
450 struct rds_info_iterator *iter,
451 struct rds_info_lengths *lens,
452 int (*visitor)(struct rds_connection *, void *),
453 size_t item_len)
454{
455 uint64_t buffer[(item_len + 7) / 8];
456 struct hlist_head *head;
457 struct rds_connection *conn;
458 size_t i;
459
460 rcu_read_lock();
461
462 lens->nr = 0;
463 lens->each = item_len;
464
465 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
466 i++, head++) {
467 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
468
469 /* XXX no c_lock usage.. */
470 if (!visitor(conn, buffer))
471 continue;
472
473 /* We copy as much as we can fit in the buffer,
474 * but we count all items so that the caller
475 * can resize the buffer. */
476 if (len >= item_len) {
477 rds_info_copy(iter, buffer, item_len);
478 len -= item_len;
479 }
480 lens->nr++;
481 }
482 }
483 rcu_read_unlock();
484}
485EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
486
487static int rds_conn_info_visitor(struct rds_connection *conn,
488 void *buffer)
489{
490 struct rds_info_connection *cinfo = buffer;
491
492 cinfo->next_tx_seq = conn->c_next_tx_seq;
493 cinfo->next_rx_seq = conn->c_next_rx_seq;
494 cinfo->laddr = conn->c_laddr;
495 cinfo->faddr = conn->c_faddr;
496 strncpy(cinfo->transport, conn->c_trans->t_name,
497 sizeof(cinfo->transport));
498 cinfo->flags = 0;
499
500 rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &conn->c_flags),
501 SENDING);
502 /* XXX Future: return the state rather than these funky bits */
503 rds_conn_info_set(cinfo->flags,
504 atomic_read(&conn->c_state) == RDS_CONN_CONNECTING,
505 CONNECTING);
506 rds_conn_info_set(cinfo->flags,
507 atomic_read(&conn->c_state) == RDS_CONN_UP,
508 CONNECTED);
509 return 1;
510}
511
512static void rds_conn_info(struct socket *sock, unsigned int len,
513 struct rds_info_iterator *iter,
514 struct rds_info_lengths *lens)
515{
516 rds_for_each_conn_info(sock, len, iter, lens,
517 rds_conn_info_visitor,
518 sizeof(struct rds_info_connection));
519}
520
521int rds_conn_init(void)
522{
523 rds_conn_slab = kmem_cache_create("rds_connection",
524 sizeof(struct rds_connection),
525 0, 0, NULL);
526 if (!rds_conn_slab)
527 return -ENOMEM;
528
529 rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
530 rds_info_register_func(RDS_INFO_SEND_MESSAGES,
531 rds_conn_message_info_send);
532 rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
533 rds_conn_message_info_retrans);
534
535 return 0;
536}
537
538void rds_conn_exit(void)
539{
540 rds_loop_exit();
541
542 WARN_ON(!hlist_empty(rds_conn_hash));
543
544 kmem_cache_destroy(rds_conn_slab);
545
546 rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
547 rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
548 rds_conn_message_info_send);
549 rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
550 rds_conn_message_info_retrans);
551}
552
553/*
554 * Force a disconnect
555 */
556void rds_conn_drop(struct rds_connection *conn)
557{
558 atomic_set(&conn->c_state, RDS_CONN_ERROR);
559 queue_work(rds_wq, &conn->c_down_w);
560}
561EXPORT_SYMBOL_GPL(rds_conn_drop);
562
563/*
564 * If the connection is down, trigger a connect. We may have scheduled a
565 * delayed reconnect however - in this case we should not interfere.
566 */
567void rds_conn_connect_if_down(struct rds_connection *conn)
568{
569 if (rds_conn_state(conn) == RDS_CONN_DOWN &&
570 !test_and_set_bit(RDS_RECONNECT_PENDING, &conn->c_flags))
571 queue_delayed_work(rds_wq, &conn->c_conn_w, 0);
572}
573EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
574
575/*
576 * An error occurred on the connection
577 */
578void
579__rds_conn_error(struct rds_connection *conn, const char *fmt, ...)
580{
581 va_list ap;
582
583 va_start(ap, fmt);
584 vprintk(fmt, ap);
585 va_end(ap);
586
587 rds_conn_drop(conn);
588}
1/*
2 * Copyright (c) 2006, 2018 Oracle and/or its affiliates. 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>
35#include <linux/slab.h>
36#include <linux/export.h>
37#include <net/ipv6.h>
38#include <net/inet6_hashtables.h>
39#include <net/addrconf.h>
40
41#include "rds.h"
42#include "loop.h"
43
44#define RDS_CONNECTION_HASH_BITS 12
45#define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS)
46#define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1)
47
48/* converting this to RCU is a chore for another day.. */
49static DEFINE_SPINLOCK(rds_conn_lock);
50static unsigned long rds_conn_count;
51static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES];
52static struct kmem_cache *rds_conn_slab;
53
54static struct hlist_head *rds_conn_bucket(const struct in6_addr *laddr,
55 const struct in6_addr *faddr)
56{
57 static u32 rds6_hash_secret __read_mostly;
58 static u32 rds_hash_secret __read_mostly;
59
60 u32 lhash, fhash, hash;
61
62 net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret));
63 net_get_random_once(&rds6_hash_secret, sizeof(rds6_hash_secret));
64
65 lhash = (__force u32)laddr->s6_addr32[3];
66#if IS_ENABLED(CONFIG_IPV6)
67 fhash = __ipv6_addr_jhash(faddr, rds6_hash_secret);
68#else
69 fhash = (__force u32)faddr->s6_addr32[3];
70#endif
71 hash = __inet_ehashfn(lhash, 0, fhash, 0, rds_hash_secret);
72
73 return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
74}
75
76#define rds_conn_info_set(var, test, suffix) do { \
77 if (test) \
78 var |= RDS_INFO_CONNECTION_FLAG_##suffix; \
79} while (0)
80
81/* rcu read lock must be held or the connection spinlock */
82static struct rds_connection *rds_conn_lookup(struct net *net,
83 struct hlist_head *head,
84 const struct in6_addr *laddr,
85 const struct in6_addr *faddr,
86 struct rds_transport *trans,
87 u8 tos, int dev_if)
88{
89 struct rds_connection *conn, *ret = NULL;
90
91 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
92 if (ipv6_addr_equal(&conn->c_faddr, faddr) &&
93 ipv6_addr_equal(&conn->c_laddr, laddr) &&
94 conn->c_trans == trans &&
95 conn->c_tos == tos &&
96 net == rds_conn_net(conn) &&
97 conn->c_dev_if == dev_if) {
98 ret = conn;
99 break;
100 }
101 }
102 rdsdebug("returning conn %p for %pI6c -> %pI6c\n", ret,
103 laddr, faddr);
104 return ret;
105}
106
107/*
108 * This is called by transports as they're bringing down a connection.
109 * It clears partial message state so that the transport can start sending
110 * and receiving over this connection again in the future. It is up to
111 * the transport to have serialized this call with its send and recv.
112 */
113static void rds_conn_path_reset(struct rds_conn_path *cp)
114{
115 struct rds_connection *conn = cp->cp_conn;
116
117 rdsdebug("connection %pI6c to %pI6c reset\n",
118 &conn->c_laddr, &conn->c_faddr);
119
120 rds_stats_inc(s_conn_reset);
121 rds_send_path_reset(cp);
122 cp->cp_flags = 0;
123
124 /* Do not clear next_rx_seq here, else we cannot distinguish
125 * retransmitted packets from new packets, and will hand all
126 * of them to the application. That is not consistent with the
127 * reliability guarantees of RDS. */
128}
129
130static void __rds_conn_path_init(struct rds_connection *conn,
131 struct rds_conn_path *cp, bool is_outgoing)
132{
133 spin_lock_init(&cp->cp_lock);
134 cp->cp_next_tx_seq = 1;
135 init_waitqueue_head(&cp->cp_waitq);
136 INIT_LIST_HEAD(&cp->cp_send_queue);
137 INIT_LIST_HEAD(&cp->cp_retrans);
138
139 cp->cp_conn = conn;
140 atomic_set(&cp->cp_state, RDS_CONN_DOWN);
141 cp->cp_send_gen = 0;
142 cp->cp_reconnect_jiffies = 0;
143 cp->cp_conn->c_proposed_version = RDS_PROTOCOL_VERSION;
144 INIT_DELAYED_WORK(&cp->cp_send_w, rds_send_worker);
145 INIT_DELAYED_WORK(&cp->cp_recv_w, rds_recv_worker);
146 INIT_DELAYED_WORK(&cp->cp_conn_w, rds_connect_worker);
147 INIT_WORK(&cp->cp_down_w, rds_shutdown_worker);
148 mutex_init(&cp->cp_cm_lock);
149 cp->cp_flags = 0;
150}
151
152/*
153 * There is only every one 'conn' for a given pair of addresses in the
154 * system at a time. They contain messages to be retransmitted and so
155 * span the lifetime of the actual underlying transport connections.
156 *
157 * For now they are not garbage collected once they're created. They
158 * are torn down as the module is removed, if ever.
159 */
160static struct rds_connection *__rds_conn_create(struct net *net,
161 const struct in6_addr *laddr,
162 const struct in6_addr *faddr,
163 struct rds_transport *trans,
164 gfp_t gfp, u8 tos,
165 int is_outgoing,
166 int dev_if)
167{
168 struct rds_connection *conn, *parent = NULL;
169 struct hlist_head *head = rds_conn_bucket(laddr, faddr);
170 struct rds_transport *loop_trans;
171 unsigned long flags;
172 int ret, i;
173 int npaths = (trans->t_mp_capable ? RDS_MPATH_WORKERS : 1);
174
175 rcu_read_lock();
176 conn = rds_conn_lookup(net, head, laddr, faddr, trans, tos, dev_if);
177 if (conn &&
178 conn->c_loopback &&
179 conn->c_trans != &rds_loop_transport &&
180 ipv6_addr_equal(laddr, faddr) &&
181 !is_outgoing) {
182 /* This is a looped back IB connection, and we're
183 * called by the code handling the incoming connect.
184 * We need a second connection object into which we
185 * can stick the other QP. */
186 parent = conn;
187 conn = parent->c_passive;
188 }
189 rcu_read_unlock();
190 if (conn)
191 goto out;
192
193 conn = kmem_cache_zalloc(rds_conn_slab, gfp);
194 if (!conn) {
195 conn = ERR_PTR(-ENOMEM);
196 goto out;
197 }
198 conn->c_path = kcalloc(npaths, sizeof(struct rds_conn_path), gfp);
199 if (!conn->c_path) {
200 kmem_cache_free(rds_conn_slab, conn);
201 conn = ERR_PTR(-ENOMEM);
202 goto out;
203 }
204
205 INIT_HLIST_NODE(&conn->c_hash_node);
206 conn->c_laddr = *laddr;
207 conn->c_isv6 = !ipv6_addr_v4mapped(laddr);
208 conn->c_faddr = *faddr;
209 conn->c_dev_if = dev_if;
210 conn->c_tos = tos;
211
212#if IS_ENABLED(CONFIG_IPV6)
213 /* If the local address is link local, set c_bound_if to be the
214 * index used for this connection. Otherwise, set it to 0 as
215 * the socket is not bound to an interface. c_bound_if is used
216 * to look up a socket when a packet is received
217 */
218 if (ipv6_addr_type(laddr) & IPV6_ADDR_LINKLOCAL)
219 conn->c_bound_if = dev_if;
220 else
221#endif
222 conn->c_bound_if = 0;
223
224 rds_conn_net_set(conn, net);
225
226 ret = rds_cong_get_maps(conn);
227 if (ret) {
228 kfree(conn->c_path);
229 kmem_cache_free(rds_conn_slab, conn);
230 conn = ERR_PTR(ret);
231 goto out;
232 }
233
234 /*
235 * This is where a connection becomes loopback. If *any* RDS sockets
236 * can bind to the destination address then we'd rather the messages
237 * flow through loopback rather than either transport.
238 */
239 loop_trans = rds_trans_get_preferred(net, faddr, conn->c_dev_if);
240 if (loop_trans) {
241 rds_trans_put(loop_trans);
242 conn->c_loopback = 1;
243 if (is_outgoing && trans->t_prefer_loopback) {
244 /* "outgoing" connection - and the transport
245 * says it wants the connection handled by the
246 * loopback transport. This is what TCP does.
247 */
248 trans = &rds_loop_transport;
249 }
250 }
251
252 conn->c_trans = trans;
253
254 init_waitqueue_head(&conn->c_hs_waitq);
255 for (i = 0; i < npaths; i++) {
256 __rds_conn_path_init(conn, &conn->c_path[i],
257 is_outgoing);
258 conn->c_path[i].cp_index = i;
259 }
260 rcu_read_lock();
261 if (rds_destroy_pending(conn))
262 ret = -ENETDOWN;
263 else
264 ret = trans->conn_alloc(conn, GFP_ATOMIC);
265 if (ret) {
266 rcu_read_unlock();
267 kfree(conn->c_path);
268 kmem_cache_free(rds_conn_slab, conn);
269 conn = ERR_PTR(ret);
270 goto out;
271 }
272
273 rdsdebug("allocated conn %p for %pI6c -> %pI6c over %s %s\n",
274 conn, laddr, faddr,
275 strnlen(trans->t_name, sizeof(trans->t_name)) ?
276 trans->t_name : "[unknown]", is_outgoing ? "(outgoing)" : "");
277
278 /*
279 * Since we ran without holding the conn lock, someone could
280 * have created the same conn (either normal or passive) in the
281 * interim. We check while holding the lock. If we won, we complete
282 * init and return our conn. If we lost, we rollback and return the
283 * other one.
284 */
285 spin_lock_irqsave(&rds_conn_lock, flags);
286 if (parent) {
287 /* Creating passive conn */
288 if (parent->c_passive) {
289 trans->conn_free(conn->c_path[0].cp_transport_data);
290 kfree(conn->c_path);
291 kmem_cache_free(rds_conn_slab, conn);
292 conn = parent->c_passive;
293 } else {
294 parent->c_passive = conn;
295 rds_cong_add_conn(conn);
296 rds_conn_count++;
297 }
298 } else {
299 /* Creating normal conn */
300 struct rds_connection *found;
301
302 found = rds_conn_lookup(net, head, laddr, faddr, trans,
303 tos, dev_if);
304 if (found) {
305 struct rds_conn_path *cp;
306 int i;
307
308 for (i = 0; i < npaths; i++) {
309 cp = &conn->c_path[i];
310 /* The ->conn_alloc invocation may have
311 * allocated resource for all paths, so all
312 * of them may have to be freed here.
313 */
314 if (cp->cp_transport_data)
315 trans->conn_free(cp->cp_transport_data);
316 }
317 kfree(conn->c_path);
318 kmem_cache_free(rds_conn_slab, conn);
319 conn = found;
320 } else {
321 conn->c_my_gen_num = rds_gen_num;
322 conn->c_peer_gen_num = 0;
323 hlist_add_head_rcu(&conn->c_hash_node, head);
324 rds_cong_add_conn(conn);
325 rds_conn_count++;
326 }
327 }
328 spin_unlock_irqrestore(&rds_conn_lock, flags);
329 rcu_read_unlock();
330
331out:
332 return conn;
333}
334
335struct rds_connection *rds_conn_create(struct net *net,
336 const struct in6_addr *laddr,
337 const struct in6_addr *faddr,
338 struct rds_transport *trans, u8 tos,
339 gfp_t gfp, int dev_if)
340{
341 return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 0, dev_if);
342}
343EXPORT_SYMBOL_GPL(rds_conn_create);
344
345struct rds_connection *rds_conn_create_outgoing(struct net *net,
346 const struct in6_addr *laddr,
347 const struct in6_addr *faddr,
348 struct rds_transport *trans,
349 u8 tos, gfp_t gfp, int dev_if)
350{
351 return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 1, dev_if);
352}
353EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
354
355void rds_conn_shutdown(struct rds_conn_path *cp)
356{
357 struct rds_connection *conn = cp->cp_conn;
358
359 /* shut it down unless it's down already */
360 if (!rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_DOWN)) {
361 /*
362 * Quiesce the connection mgmt handlers before we start tearing
363 * things down. We don't hold the mutex for the entire
364 * duration of the shutdown operation, else we may be
365 * deadlocking with the CM handler. Instead, the CM event
366 * handler is supposed to check for state DISCONNECTING
367 */
368 mutex_lock(&cp->cp_cm_lock);
369 if (!rds_conn_path_transition(cp, RDS_CONN_UP,
370 RDS_CONN_DISCONNECTING) &&
371 !rds_conn_path_transition(cp, RDS_CONN_ERROR,
372 RDS_CONN_DISCONNECTING)) {
373 rds_conn_path_error(cp,
374 "shutdown called in state %d\n",
375 atomic_read(&cp->cp_state));
376 mutex_unlock(&cp->cp_cm_lock);
377 return;
378 }
379 mutex_unlock(&cp->cp_cm_lock);
380
381 wait_event(cp->cp_waitq,
382 !test_bit(RDS_IN_XMIT, &cp->cp_flags));
383 wait_event(cp->cp_waitq,
384 !test_bit(RDS_RECV_REFILL, &cp->cp_flags));
385
386 conn->c_trans->conn_path_shutdown(cp);
387 rds_conn_path_reset(cp);
388
389 if (!rds_conn_path_transition(cp, RDS_CONN_DISCONNECTING,
390 RDS_CONN_DOWN) &&
391 !rds_conn_path_transition(cp, RDS_CONN_ERROR,
392 RDS_CONN_DOWN)) {
393 /* This can happen - eg when we're in the middle of tearing
394 * down the connection, and someone unloads the rds module.
395 * Quite reproducible with loopback connections.
396 * Mostly harmless.
397 *
398 * Note that this also happens with rds-tcp because
399 * we could have triggered rds_conn_path_drop in irq
400 * mode from rds_tcp_state change on the receipt of
401 * a FIN, thus we need to recheck for RDS_CONN_ERROR
402 * here.
403 */
404 rds_conn_path_error(cp, "%s: failed to transition "
405 "to state DOWN, current state "
406 "is %d\n", __func__,
407 atomic_read(&cp->cp_state));
408 return;
409 }
410 }
411
412 /* Then reconnect if it's still live.
413 * The passive side of an IB loopback connection is never added
414 * to the conn hash, so we never trigger a reconnect on this
415 * conn - the reconnect is always triggered by the active peer. */
416 cancel_delayed_work_sync(&cp->cp_conn_w);
417 rcu_read_lock();
418 if (!hlist_unhashed(&conn->c_hash_node)) {
419 rcu_read_unlock();
420 rds_queue_reconnect(cp);
421 } else {
422 rcu_read_unlock();
423 }
424}
425
426/* destroy a single rds_conn_path. rds_conn_destroy() iterates over
427 * all paths using rds_conn_path_destroy()
428 */
429static void rds_conn_path_destroy(struct rds_conn_path *cp)
430{
431 struct rds_message *rm, *rtmp;
432
433 if (!cp->cp_transport_data)
434 return;
435
436 /* make sure lingering queued work won't try to ref the conn */
437 cancel_delayed_work_sync(&cp->cp_send_w);
438 cancel_delayed_work_sync(&cp->cp_recv_w);
439
440 rds_conn_path_drop(cp, true);
441 flush_work(&cp->cp_down_w);
442
443 /* tear down queued messages */
444 list_for_each_entry_safe(rm, rtmp,
445 &cp->cp_send_queue,
446 m_conn_item) {
447 list_del_init(&rm->m_conn_item);
448 BUG_ON(!list_empty(&rm->m_sock_item));
449 rds_message_put(rm);
450 }
451 if (cp->cp_xmit_rm)
452 rds_message_put(cp->cp_xmit_rm);
453
454 WARN_ON(delayed_work_pending(&cp->cp_send_w));
455 WARN_ON(delayed_work_pending(&cp->cp_recv_w));
456 WARN_ON(delayed_work_pending(&cp->cp_conn_w));
457 WARN_ON(work_pending(&cp->cp_down_w));
458
459 cp->cp_conn->c_trans->conn_free(cp->cp_transport_data);
460}
461
462/*
463 * Stop and free a connection.
464 *
465 * This can only be used in very limited circumstances. It assumes that once
466 * the conn has been shutdown that no one else is referencing the connection.
467 * We can only ensure this in the rmmod path in the current code.
468 */
469void rds_conn_destroy(struct rds_connection *conn)
470{
471 unsigned long flags;
472 int i;
473 struct rds_conn_path *cp;
474 int npaths = (conn->c_trans->t_mp_capable ? RDS_MPATH_WORKERS : 1);
475
476 rdsdebug("freeing conn %p for %pI4 -> "
477 "%pI4\n", conn, &conn->c_laddr,
478 &conn->c_faddr);
479
480 /* Ensure conn will not be scheduled for reconnect */
481 spin_lock_irq(&rds_conn_lock);
482 hlist_del_init_rcu(&conn->c_hash_node);
483 spin_unlock_irq(&rds_conn_lock);
484 synchronize_rcu();
485
486 /* shut the connection down */
487 for (i = 0; i < npaths; i++) {
488 cp = &conn->c_path[i];
489 rds_conn_path_destroy(cp);
490 BUG_ON(!list_empty(&cp->cp_retrans));
491 }
492
493 /*
494 * The congestion maps aren't freed up here. They're
495 * freed by rds_cong_exit() after all the connections
496 * have been freed.
497 */
498 rds_cong_remove_conn(conn);
499
500 kfree(conn->c_path);
501 kmem_cache_free(rds_conn_slab, conn);
502
503 spin_lock_irqsave(&rds_conn_lock, flags);
504 rds_conn_count--;
505 spin_unlock_irqrestore(&rds_conn_lock, flags);
506}
507EXPORT_SYMBOL_GPL(rds_conn_destroy);
508
509static void __rds_inc_msg_cp(struct rds_incoming *inc,
510 struct rds_info_iterator *iter,
511 void *saddr, void *daddr, int flip, bool isv6)
512{
513#if IS_ENABLED(CONFIG_IPV6)
514 if (isv6)
515 rds6_inc_info_copy(inc, iter, saddr, daddr, flip);
516 else
517#endif
518 rds_inc_info_copy(inc, iter, *(__be32 *)saddr,
519 *(__be32 *)daddr, flip);
520}
521
522static void rds_conn_message_info_cmn(struct socket *sock, unsigned int len,
523 struct rds_info_iterator *iter,
524 struct rds_info_lengths *lens,
525 int want_send, bool isv6)
526{
527 struct hlist_head *head;
528 struct list_head *list;
529 struct rds_connection *conn;
530 struct rds_message *rm;
531 unsigned int total = 0;
532 unsigned long flags;
533 size_t i;
534 int j;
535
536 if (isv6)
537 len /= sizeof(struct rds6_info_message);
538 else
539 len /= sizeof(struct rds_info_message);
540
541 rcu_read_lock();
542
543 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
544 i++, head++) {
545 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
546 struct rds_conn_path *cp;
547 int npaths;
548
549 if (!isv6 && conn->c_isv6)
550 continue;
551
552 npaths = (conn->c_trans->t_mp_capable ?
553 RDS_MPATH_WORKERS : 1);
554
555 for (j = 0; j < npaths; j++) {
556 cp = &conn->c_path[j];
557 if (want_send)
558 list = &cp->cp_send_queue;
559 else
560 list = &cp->cp_retrans;
561
562 spin_lock_irqsave(&cp->cp_lock, flags);
563
564 /* XXX too lazy to maintain counts.. */
565 list_for_each_entry(rm, list, m_conn_item) {
566 total++;
567 if (total <= len)
568 __rds_inc_msg_cp(&rm->m_inc,
569 iter,
570 &conn->c_laddr,
571 &conn->c_faddr,
572 0, isv6);
573 }
574
575 spin_unlock_irqrestore(&cp->cp_lock, flags);
576 }
577 }
578 }
579 rcu_read_unlock();
580
581 lens->nr = total;
582 if (isv6)
583 lens->each = sizeof(struct rds6_info_message);
584 else
585 lens->each = sizeof(struct rds_info_message);
586}
587
588static void rds_conn_message_info(struct socket *sock, unsigned int len,
589 struct rds_info_iterator *iter,
590 struct rds_info_lengths *lens,
591 int want_send)
592{
593 rds_conn_message_info_cmn(sock, len, iter, lens, want_send, false);
594}
595
596#if IS_ENABLED(CONFIG_IPV6)
597static void rds6_conn_message_info(struct socket *sock, unsigned int len,
598 struct rds_info_iterator *iter,
599 struct rds_info_lengths *lens,
600 int want_send)
601{
602 rds_conn_message_info_cmn(sock, len, iter, lens, want_send, true);
603}
604#endif
605
606static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
607 struct rds_info_iterator *iter,
608 struct rds_info_lengths *lens)
609{
610 rds_conn_message_info(sock, len, iter, lens, 1);
611}
612
613#if IS_ENABLED(CONFIG_IPV6)
614static void rds6_conn_message_info_send(struct socket *sock, unsigned int len,
615 struct rds_info_iterator *iter,
616 struct rds_info_lengths *lens)
617{
618 rds6_conn_message_info(sock, len, iter, lens, 1);
619}
620#endif
621
622static void rds_conn_message_info_retrans(struct socket *sock,
623 unsigned int len,
624 struct rds_info_iterator *iter,
625 struct rds_info_lengths *lens)
626{
627 rds_conn_message_info(sock, len, iter, lens, 0);
628}
629
630#if IS_ENABLED(CONFIG_IPV6)
631static void rds6_conn_message_info_retrans(struct socket *sock,
632 unsigned int len,
633 struct rds_info_iterator *iter,
634 struct rds_info_lengths *lens)
635{
636 rds6_conn_message_info(sock, len, iter, lens, 0);
637}
638#endif
639
640void rds_for_each_conn_info(struct socket *sock, unsigned int len,
641 struct rds_info_iterator *iter,
642 struct rds_info_lengths *lens,
643 int (*visitor)(struct rds_connection *, void *),
644 u64 *buffer,
645 size_t item_len)
646{
647 struct hlist_head *head;
648 struct rds_connection *conn;
649 size_t i;
650
651 rcu_read_lock();
652
653 lens->nr = 0;
654 lens->each = item_len;
655
656 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
657 i++, head++) {
658 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
659
660 /* XXX no c_lock usage.. */
661 if (!visitor(conn, buffer))
662 continue;
663
664 /* We copy as much as we can fit in the buffer,
665 * but we count all items so that the caller
666 * can resize the buffer. */
667 if (len >= item_len) {
668 rds_info_copy(iter, buffer, item_len);
669 len -= item_len;
670 }
671 lens->nr++;
672 }
673 }
674 rcu_read_unlock();
675}
676EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
677
678static void rds_walk_conn_path_info(struct socket *sock, unsigned int len,
679 struct rds_info_iterator *iter,
680 struct rds_info_lengths *lens,
681 int (*visitor)(struct rds_conn_path *, void *),
682 u64 *buffer,
683 size_t item_len)
684{
685 struct hlist_head *head;
686 struct rds_connection *conn;
687 size_t i;
688
689 rcu_read_lock();
690
691 lens->nr = 0;
692 lens->each = item_len;
693
694 for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
695 i++, head++) {
696 hlist_for_each_entry_rcu(conn, head, c_hash_node) {
697 struct rds_conn_path *cp;
698
699 /* XXX We only copy the information from the first
700 * path for now. The problem is that if there are
701 * more than one underlying paths, we cannot report
702 * information of all of them using the existing
703 * API. For example, there is only one next_tx_seq,
704 * which path's next_tx_seq should we report? It is
705 * a bug in the design of MPRDS.
706 */
707 cp = conn->c_path;
708
709 /* XXX no cp_lock usage.. */
710 if (!visitor(cp, buffer))
711 continue;
712
713 /* We copy as much as we can fit in the buffer,
714 * but we count all items so that the caller
715 * can resize the buffer.
716 */
717 if (len >= item_len) {
718 rds_info_copy(iter, buffer, item_len);
719 len -= item_len;
720 }
721 lens->nr++;
722 }
723 }
724 rcu_read_unlock();
725}
726
727static int rds_conn_info_visitor(struct rds_conn_path *cp, void *buffer)
728{
729 struct rds_info_connection *cinfo = buffer;
730 struct rds_connection *conn = cp->cp_conn;
731
732 if (conn->c_isv6)
733 return 0;
734
735 cinfo->next_tx_seq = cp->cp_next_tx_seq;
736 cinfo->next_rx_seq = cp->cp_next_rx_seq;
737 cinfo->laddr = conn->c_laddr.s6_addr32[3];
738 cinfo->faddr = conn->c_faddr.s6_addr32[3];
739 cinfo->tos = conn->c_tos;
740 strncpy(cinfo->transport, conn->c_trans->t_name,
741 sizeof(cinfo->transport));
742 cinfo->flags = 0;
743
744 rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags),
745 SENDING);
746 /* XXX Future: return the state rather than these funky bits */
747 rds_conn_info_set(cinfo->flags,
748 atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING,
749 CONNECTING);
750 rds_conn_info_set(cinfo->flags,
751 atomic_read(&cp->cp_state) == RDS_CONN_UP,
752 CONNECTED);
753 return 1;
754}
755
756#if IS_ENABLED(CONFIG_IPV6)
757static int rds6_conn_info_visitor(struct rds_conn_path *cp, void *buffer)
758{
759 struct rds6_info_connection *cinfo6 = buffer;
760 struct rds_connection *conn = cp->cp_conn;
761
762 cinfo6->next_tx_seq = cp->cp_next_tx_seq;
763 cinfo6->next_rx_seq = cp->cp_next_rx_seq;
764 cinfo6->laddr = conn->c_laddr;
765 cinfo6->faddr = conn->c_faddr;
766 strncpy(cinfo6->transport, conn->c_trans->t_name,
767 sizeof(cinfo6->transport));
768 cinfo6->flags = 0;
769
770 rds_conn_info_set(cinfo6->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags),
771 SENDING);
772 /* XXX Future: return the state rather than these funky bits */
773 rds_conn_info_set(cinfo6->flags,
774 atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING,
775 CONNECTING);
776 rds_conn_info_set(cinfo6->flags,
777 atomic_read(&cp->cp_state) == RDS_CONN_UP,
778 CONNECTED);
779 /* Just return 1 as there is no error case. This is a helper function
780 * for rds_walk_conn_path_info() and it wants a return value.
781 */
782 return 1;
783}
784#endif
785
786static void rds_conn_info(struct socket *sock, unsigned int len,
787 struct rds_info_iterator *iter,
788 struct rds_info_lengths *lens)
789{
790 u64 buffer[(sizeof(struct rds_info_connection) + 7) / 8];
791
792 rds_walk_conn_path_info(sock, len, iter, lens,
793 rds_conn_info_visitor,
794 buffer,
795 sizeof(struct rds_info_connection));
796}
797
798#if IS_ENABLED(CONFIG_IPV6)
799static void rds6_conn_info(struct socket *sock, unsigned int len,
800 struct rds_info_iterator *iter,
801 struct rds_info_lengths *lens)
802{
803 u64 buffer[(sizeof(struct rds6_info_connection) + 7) / 8];
804
805 rds_walk_conn_path_info(sock, len, iter, lens,
806 rds6_conn_info_visitor,
807 buffer,
808 sizeof(struct rds6_info_connection));
809}
810#endif
811
812int rds_conn_init(void)
813{
814 int ret;
815
816 ret = rds_loop_net_init(); /* register pernet callback */
817 if (ret)
818 return ret;
819
820 rds_conn_slab = kmem_cache_create("rds_connection",
821 sizeof(struct rds_connection),
822 0, 0, NULL);
823 if (!rds_conn_slab) {
824 rds_loop_net_exit();
825 return -ENOMEM;
826 }
827
828 rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
829 rds_info_register_func(RDS_INFO_SEND_MESSAGES,
830 rds_conn_message_info_send);
831 rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
832 rds_conn_message_info_retrans);
833#if IS_ENABLED(CONFIG_IPV6)
834 rds_info_register_func(RDS6_INFO_CONNECTIONS, rds6_conn_info);
835 rds_info_register_func(RDS6_INFO_SEND_MESSAGES,
836 rds6_conn_message_info_send);
837 rds_info_register_func(RDS6_INFO_RETRANS_MESSAGES,
838 rds6_conn_message_info_retrans);
839#endif
840 return 0;
841}
842
843void rds_conn_exit(void)
844{
845 rds_loop_net_exit(); /* unregister pernet callback */
846 rds_loop_exit();
847
848 WARN_ON(!hlist_empty(rds_conn_hash));
849
850 kmem_cache_destroy(rds_conn_slab);
851
852 rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
853 rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
854 rds_conn_message_info_send);
855 rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
856 rds_conn_message_info_retrans);
857#if IS_ENABLED(CONFIG_IPV6)
858 rds_info_deregister_func(RDS6_INFO_CONNECTIONS, rds6_conn_info);
859 rds_info_deregister_func(RDS6_INFO_SEND_MESSAGES,
860 rds6_conn_message_info_send);
861 rds_info_deregister_func(RDS6_INFO_RETRANS_MESSAGES,
862 rds6_conn_message_info_retrans);
863#endif
864}
865
866/*
867 * Force a disconnect
868 */
869void rds_conn_path_drop(struct rds_conn_path *cp, bool destroy)
870{
871 atomic_set(&cp->cp_state, RDS_CONN_ERROR);
872
873 rcu_read_lock();
874 if (!destroy && rds_destroy_pending(cp->cp_conn)) {
875 rcu_read_unlock();
876 return;
877 }
878 queue_work(rds_wq, &cp->cp_down_w);
879 rcu_read_unlock();
880}
881EXPORT_SYMBOL_GPL(rds_conn_path_drop);
882
883void rds_conn_drop(struct rds_connection *conn)
884{
885 WARN_ON(conn->c_trans->t_mp_capable);
886 rds_conn_path_drop(&conn->c_path[0], false);
887}
888EXPORT_SYMBOL_GPL(rds_conn_drop);
889
890/*
891 * If the connection is down, trigger a connect. We may have scheduled a
892 * delayed reconnect however - in this case we should not interfere.
893 */
894void rds_conn_path_connect_if_down(struct rds_conn_path *cp)
895{
896 rcu_read_lock();
897 if (rds_destroy_pending(cp->cp_conn)) {
898 rcu_read_unlock();
899 return;
900 }
901 if (rds_conn_path_state(cp) == RDS_CONN_DOWN &&
902 !test_and_set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags))
903 queue_delayed_work(rds_wq, &cp->cp_conn_w, 0);
904 rcu_read_unlock();
905}
906EXPORT_SYMBOL_GPL(rds_conn_path_connect_if_down);
907
908/* Check connectivity of all paths
909 */
910void rds_check_all_paths(struct rds_connection *conn)
911{
912 int i = 0;
913
914 do {
915 rds_conn_path_connect_if_down(&conn->c_path[i]);
916 } while (++i < conn->c_npaths);
917}
918
919void rds_conn_connect_if_down(struct rds_connection *conn)
920{
921 WARN_ON(conn->c_trans->t_mp_capable);
922 rds_conn_path_connect_if_down(&conn->c_path[0]);
923}
924EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
925
926void
927__rds_conn_path_error(struct rds_conn_path *cp, const char *fmt, ...)
928{
929 va_list ap;
930
931 va_start(ap, fmt);
932 vprintk(fmt, ap);
933 va_end(ap);
934
935 rds_conn_path_drop(cp, false);
936}