1 /* RxRPC individual remote procedure call handling
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/circ_buf.h>
15 #include <net/sock.h>
16 #include <net/af_rxrpc.h>
17 #include "ar-internal.h"
18
19 const char *const rxrpc_call_states[] = {
20 [RXRPC_CALL_CLIENT_SEND_REQUEST] = "ClSndReq",
21 [RXRPC_CALL_CLIENT_AWAIT_REPLY] = "ClAwtRpl",
22 [RXRPC_CALL_CLIENT_RECV_REPLY] = "ClRcvRpl",
23 [RXRPC_CALL_CLIENT_FINAL_ACK] = "ClFnlACK",
24 [RXRPC_CALL_SERVER_SECURING] = "SvSecure",
25 [RXRPC_CALL_SERVER_ACCEPTING] = "SvAccept",
26 [RXRPC_CALL_SERVER_RECV_REQUEST] = "SvRcvReq",
27 [RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq",
28 [RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl",
29 [RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK",
30 [RXRPC_CALL_COMPLETE] = "Complete",
31 [RXRPC_CALL_SERVER_BUSY] = "SvBusy ",
32 [RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
33 [RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
34 [RXRPC_CALL_NETWORK_ERROR] = "NetError",
35 [RXRPC_CALL_DEAD] = "Dead ",
36 };
37
38 struct kmem_cache *rxrpc_call_jar;
39 LIST_HEAD(rxrpc_calls);
40 DEFINE_RWLOCK(rxrpc_call_lock);
41 static unsigned rxrpc_call_max_lifetime = 60;
42 static unsigned rxrpc_dead_call_timeout = 2;
43
44 static void rxrpc_destroy_call(struct work_struct *work);
45 static void rxrpc_call_life_expired(unsigned long _call);
46 static void rxrpc_dead_call_expired(unsigned long _call);
47 static void rxrpc_ack_time_expired(unsigned long _call);
48 static void rxrpc_resend_time_expired(unsigned long _call);
49
50 /*
51 * allocate a new call
52 */
rxrpc_alloc_call(gfp_t gfp)53 static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
54 {
55 struct rxrpc_call *call;
56
57 call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
58 if (!call)
59 return NULL;
60
61 call->acks_winsz = 16;
62 call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
63 gfp);
64 if (!call->acks_window) {
65 kmem_cache_free(rxrpc_call_jar, call);
66 return NULL;
67 }
68
69 setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
70 (unsigned long) call);
71 setup_timer(&call->deadspan, &rxrpc_dead_call_expired,
72 (unsigned long) call);
73 setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
74 (unsigned long) call);
75 setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
76 (unsigned long) call);
77 INIT_WORK(&call->destroyer, &rxrpc_destroy_call);
78 INIT_WORK(&call->processor, &rxrpc_process_call);
79 INIT_LIST_HEAD(&call->accept_link);
80 skb_queue_head_init(&call->rx_queue);
81 skb_queue_head_init(&call->rx_oos_queue);
82 init_waitqueue_head(&call->tx_waitq);
83 spin_lock_init(&call->lock);
84 rwlock_init(&call->state_lock);
85 atomic_set(&call->usage, 1);
86 call->debug_id = atomic_inc_return(&rxrpc_debug_id);
87 call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
88
89 memset(&call->sock_node, 0xed, sizeof(call->sock_node));
90
91 call->rx_data_expect = 1;
92 call->rx_data_eaten = 0;
93 call->rx_first_oos = 0;
94 call->ackr_win_top = call->rx_data_eaten + 1 + RXRPC_MAXACKS;
95 call->creation_jif = jiffies;
96 return call;
97 }
98
99 /*
100 * allocate a new client call and attempt to get a connection slot for it
101 */
rxrpc_alloc_client_call(struct rxrpc_sock * rx,struct rxrpc_transport * trans,struct rxrpc_conn_bundle * bundle,gfp_t gfp)102 static struct rxrpc_call *rxrpc_alloc_client_call(
103 struct rxrpc_sock *rx,
104 struct rxrpc_transport *trans,
105 struct rxrpc_conn_bundle *bundle,
106 gfp_t gfp)
107 {
108 struct rxrpc_call *call;
109 int ret;
110
111 _enter("");
112
113 ASSERT(rx != NULL);
114 ASSERT(trans != NULL);
115 ASSERT(bundle != NULL);
116
117 call = rxrpc_alloc_call(gfp);
118 if (!call)
119 return ERR_PTR(-ENOMEM);
120
121 sock_hold(&rx->sk);
122 call->socket = rx;
123 call->rx_data_post = 1;
124
125 ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
126 if (ret < 0) {
127 kmem_cache_free(rxrpc_call_jar, call);
128 return ERR_PTR(ret);
129 }
130
131 spin_lock(&call->conn->trans->peer->lock);
132 list_add(&call->error_link, &call->conn->trans->peer->error_targets);
133 spin_unlock(&call->conn->trans->peer->lock);
134
135 call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
136 add_timer(&call->lifetimer);
137
138 _leave(" = %p", call);
139 return call;
140 }
141
142 /*
143 * set up a call for the given data
144 * - called in process context with IRQs enabled
145 */
rxrpc_get_client_call(struct rxrpc_sock * rx,struct rxrpc_transport * trans,struct rxrpc_conn_bundle * bundle,unsigned long user_call_ID,int create,gfp_t gfp)146 struct rxrpc_call *rxrpc_get_client_call(struct rxrpc_sock *rx,
147 struct rxrpc_transport *trans,
148 struct rxrpc_conn_bundle *bundle,
149 unsigned long user_call_ID,
150 int create,
151 gfp_t gfp)
152 {
153 struct rxrpc_call *call, *candidate;
154 struct rb_node *p, *parent, **pp;
155
156 _enter("%p,%d,%d,%lx,%d",
157 rx, trans ? trans->debug_id : -1, bundle ? bundle->debug_id : -1,
158 user_call_ID, create);
159
160 /* search the extant calls first for one that matches the specified
161 * user ID */
162 read_lock(&rx->call_lock);
163
164 p = rx->calls.rb_node;
165 while (p) {
166 call = rb_entry(p, struct rxrpc_call, sock_node);
167
168 if (user_call_ID < call->user_call_ID)
169 p = p->rb_left;
170 else if (user_call_ID > call->user_call_ID)
171 p = p->rb_right;
172 else
173 goto found_extant_call;
174 }
175
176 read_unlock(&rx->call_lock);
177
178 if (!create || !trans)
179 return ERR_PTR(-EBADSLT);
180
181 /* not yet present - create a candidate for a new record and then
182 * redo the search */
183 candidate = rxrpc_alloc_client_call(rx, trans, bundle, gfp);
184 if (IS_ERR(candidate)) {
185 _leave(" = %ld", PTR_ERR(candidate));
186 return candidate;
187 }
188
189 candidate->user_call_ID = user_call_ID;
190 __set_bit(RXRPC_CALL_HAS_USERID, &candidate->flags);
191
192 write_lock(&rx->call_lock);
193
194 pp = &rx->calls.rb_node;
195 parent = NULL;
196 while (*pp) {
197 parent = *pp;
198 call = rb_entry(parent, struct rxrpc_call, sock_node);
199
200 if (user_call_ID < call->user_call_ID)
201 pp = &(*pp)->rb_left;
202 else if (user_call_ID > call->user_call_ID)
203 pp = &(*pp)->rb_right;
204 else
205 goto found_extant_second;
206 }
207
208 /* second search also failed; add the new call */
209 call = candidate;
210 candidate = NULL;
211 rxrpc_get_call(call);
212
213 rb_link_node(&call->sock_node, parent, pp);
214 rb_insert_color(&call->sock_node, &rx->calls);
215 write_unlock(&rx->call_lock);
216
217 write_lock_bh(&rxrpc_call_lock);
218 list_add_tail(&call->link, &rxrpc_calls);
219 write_unlock_bh(&rxrpc_call_lock);
220
221 _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
222
223 _leave(" = %p [new]", call);
224 return call;
225
226 /* we found the call in the list immediately */
227 found_extant_call:
228 rxrpc_get_call(call);
229 read_unlock(&rx->call_lock);
230 _leave(" = %p [extant %d]", call, atomic_read(&call->usage));
231 return call;
232
233 /* we found the call on the second time through the list */
234 found_extant_second:
235 rxrpc_get_call(call);
236 write_unlock(&rx->call_lock);
237 rxrpc_put_call(candidate);
238 _leave(" = %p [second %d]", call, atomic_read(&call->usage));
239 return call;
240 }
241
242 /*
243 * set up an incoming call
244 * - called in process context with IRQs enabled
245 */
rxrpc_incoming_call(struct rxrpc_sock * rx,struct rxrpc_connection * conn,struct rxrpc_header * hdr,gfp_t gfp)246 struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
247 struct rxrpc_connection *conn,
248 struct rxrpc_header *hdr,
249 gfp_t gfp)
250 {
251 struct rxrpc_call *call, *candidate;
252 struct rb_node **p, *parent;
253 __be32 call_id;
254
255 _enter(",%d,,%x", conn->debug_id, gfp);
256
257 ASSERT(rx != NULL);
258
259 candidate = rxrpc_alloc_call(gfp);
260 if (!candidate)
261 return ERR_PTR(-EBUSY);
262
263 candidate->socket = rx;
264 candidate->conn = conn;
265 candidate->cid = hdr->cid;
266 candidate->call_id = hdr->callNumber;
267 candidate->channel = ntohl(hdr->cid) & RXRPC_CHANNELMASK;
268 candidate->rx_data_post = 0;
269 candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
270 if (conn->security_ix > 0)
271 candidate->state = RXRPC_CALL_SERVER_SECURING;
272
273 write_lock_bh(&conn->lock);
274
275 /* set the channel for this call */
276 call = conn->channels[candidate->channel];
277 _debug("channel[%u] is %p", candidate->channel, call);
278 if (call && call->call_id == hdr->callNumber) {
279 /* already set; must've been a duplicate packet */
280 _debug("extant call [%d]", call->state);
281 ASSERTCMP(call->conn, ==, conn);
282
283 read_lock(&call->state_lock);
284 switch (call->state) {
285 case RXRPC_CALL_LOCALLY_ABORTED:
286 if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
287 rxrpc_queue_call(call);
288 case RXRPC_CALL_REMOTELY_ABORTED:
289 read_unlock(&call->state_lock);
290 goto aborted_call;
291 default:
292 rxrpc_get_call(call);
293 read_unlock(&call->state_lock);
294 goto extant_call;
295 }
296 }
297
298 if (call) {
299 /* it seems the channel is still in use from the previous call
300 * - ditch the old binding if its call is now complete */
301 _debug("CALL: %u { %s }",
302 call->debug_id, rxrpc_call_states[call->state]);
303
304 if (call->state >= RXRPC_CALL_COMPLETE) {
305 conn->channels[call->channel] = NULL;
306 } else {
307 write_unlock_bh(&conn->lock);
308 kmem_cache_free(rxrpc_call_jar, candidate);
309 _leave(" = -EBUSY");
310 return ERR_PTR(-EBUSY);
311 }
312 }
313
314 /* check the call number isn't duplicate */
315 _debug("check dup");
316 call_id = hdr->callNumber;
317 p = &conn->calls.rb_node;
318 parent = NULL;
319 while (*p) {
320 parent = *p;
321 call = rb_entry(parent, struct rxrpc_call, conn_node);
322
323 if (call_id < call->call_id)
324 p = &(*p)->rb_left;
325 else if (call_id > call->call_id)
326 p = &(*p)->rb_right;
327 else
328 goto old_call;
329 }
330
331 /* make the call available */
332 _debug("new call");
333 call = candidate;
334 candidate = NULL;
335 rb_link_node(&call->conn_node, parent, p);
336 rb_insert_color(&call->conn_node, &conn->calls);
337 conn->channels[call->channel] = call;
338 sock_hold(&rx->sk);
339 atomic_inc(&conn->usage);
340 write_unlock_bh(&conn->lock);
341
342 spin_lock(&conn->trans->peer->lock);
343 list_add(&call->error_link, &conn->trans->peer->error_targets);
344 spin_unlock(&conn->trans->peer->lock);
345
346 write_lock_bh(&rxrpc_call_lock);
347 list_add_tail(&call->link, &rxrpc_calls);
348 write_unlock_bh(&rxrpc_call_lock);
349
350 _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
351
352 call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
353 add_timer(&call->lifetimer);
354 _leave(" = %p {%d} [new]", call, call->debug_id);
355 return call;
356
357 extant_call:
358 write_unlock_bh(&conn->lock);
359 kmem_cache_free(rxrpc_call_jar, candidate);
360 _leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
361 return call;
362
363 aborted_call:
364 write_unlock_bh(&conn->lock);
365 kmem_cache_free(rxrpc_call_jar, candidate);
366 _leave(" = -ECONNABORTED");
367 return ERR_PTR(-ECONNABORTED);
368
369 old_call:
370 write_unlock_bh(&conn->lock);
371 kmem_cache_free(rxrpc_call_jar, candidate);
372 _leave(" = -ECONNRESET [old]");
373 return ERR_PTR(-ECONNRESET);
374 }
375
376 /*
377 * find an extant server call
378 * - called in process context with IRQs enabled
379 */
rxrpc_find_server_call(struct rxrpc_sock * rx,unsigned long user_call_ID)380 struct rxrpc_call *rxrpc_find_server_call(struct rxrpc_sock *rx,
381 unsigned long user_call_ID)
382 {
383 struct rxrpc_call *call;
384 struct rb_node *p;
385
386 _enter("%p,%lx", rx, user_call_ID);
387
388 /* search the extant calls for one that matches the specified user
389 * ID */
390 read_lock(&rx->call_lock);
391
392 p = rx->calls.rb_node;
393 while (p) {
394 call = rb_entry(p, struct rxrpc_call, sock_node);
395
396 if (user_call_ID < call->user_call_ID)
397 p = p->rb_left;
398 else if (user_call_ID > call->user_call_ID)
399 p = p->rb_right;
400 else
401 goto found_extant_call;
402 }
403
404 read_unlock(&rx->call_lock);
405 _leave(" = NULL");
406 return NULL;
407
408 /* we found the call in the list immediately */
409 found_extant_call:
410 rxrpc_get_call(call);
411 read_unlock(&rx->call_lock);
412 _leave(" = %p [%d]", call, atomic_read(&call->usage));
413 return call;
414 }
415
416 /*
417 * detach a call from a socket and set up for release
418 */
rxrpc_release_call(struct rxrpc_call * call)419 void rxrpc_release_call(struct rxrpc_call *call)
420 {
421 struct rxrpc_connection *conn = call->conn;
422 struct rxrpc_sock *rx = call->socket;
423
424 _enter("{%d,%d,%d,%d}",
425 call->debug_id, atomic_read(&call->usage),
426 atomic_read(&call->ackr_not_idle),
427 call->rx_first_oos);
428
429 spin_lock_bh(&call->lock);
430 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
431 BUG();
432 spin_unlock_bh(&call->lock);
433
434 /* dissociate from the socket
435 * - the socket's ref on the call is passed to the death timer
436 */
437 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
438
439 write_lock_bh(&rx->call_lock);
440 if (!list_empty(&call->accept_link)) {
441 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
442 call, call->events, call->flags);
443 ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
444 list_del_init(&call->accept_link);
445 sk_acceptq_removed(&rx->sk);
446 } else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
447 rb_erase(&call->sock_node, &rx->calls);
448 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
449 clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
450 }
451 write_unlock_bh(&rx->call_lock);
452
453 /* free up the channel for reuse */
454 spin_lock(&conn->trans->client_lock);
455 write_lock_bh(&conn->lock);
456 write_lock(&call->state_lock);
457
458 if (conn->channels[call->channel] == call)
459 conn->channels[call->channel] = NULL;
460
461 if (conn->out_clientflag && conn->bundle) {
462 conn->avail_calls++;
463 switch (conn->avail_calls) {
464 case 1:
465 list_move_tail(&conn->bundle_link,
466 &conn->bundle->avail_conns);
467 case 2 ... RXRPC_MAXCALLS - 1:
468 ASSERT(conn->channels[0] == NULL ||
469 conn->channels[1] == NULL ||
470 conn->channels[2] == NULL ||
471 conn->channels[3] == NULL);
472 break;
473 case RXRPC_MAXCALLS:
474 list_move_tail(&conn->bundle_link,
475 &conn->bundle->unused_conns);
476 ASSERT(conn->channels[0] == NULL &&
477 conn->channels[1] == NULL &&
478 conn->channels[2] == NULL &&
479 conn->channels[3] == NULL);
480 break;
481 default:
482 printk(KERN_ERR "RxRPC: conn->avail_calls=%d\n",
483 conn->avail_calls);
484 BUG();
485 }
486 }
487
488 spin_unlock(&conn->trans->client_lock);
489
490 if (call->state < RXRPC_CALL_COMPLETE &&
491 call->state != RXRPC_CALL_CLIENT_FINAL_ACK) {
492 _debug("+++ ABORTING STATE %d +++\n", call->state);
493 call->state = RXRPC_CALL_LOCALLY_ABORTED;
494 call->abort_code = RX_CALL_DEAD;
495 set_bit(RXRPC_CALL_ABORT, &call->events);
496 rxrpc_queue_call(call);
497 }
498 write_unlock(&call->state_lock);
499 write_unlock_bh(&conn->lock);
500
501 /* clean up the Rx queue */
502 if (!skb_queue_empty(&call->rx_queue) ||
503 !skb_queue_empty(&call->rx_oos_queue)) {
504 struct rxrpc_skb_priv *sp;
505 struct sk_buff *skb;
506
507 _debug("purge Rx queues");
508
509 spin_lock_bh(&call->lock);
510 while ((skb = skb_dequeue(&call->rx_queue)) ||
511 (skb = skb_dequeue(&call->rx_oos_queue))) {
512 sp = rxrpc_skb(skb);
513 if (sp->call) {
514 ASSERTCMP(sp->call, ==, call);
515 rxrpc_put_call(call);
516 sp->call = NULL;
517 }
518 skb->destructor = NULL;
519 spin_unlock_bh(&call->lock);
520
521 _debug("- zap %s %%%u #%u",
522 rxrpc_pkts[sp->hdr.type],
523 ntohl(sp->hdr.serial),
524 ntohl(sp->hdr.seq));
525 rxrpc_free_skb(skb);
526 spin_lock_bh(&call->lock);
527 }
528 spin_unlock_bh(&call->lock);
529
530 ASSERTCMP(call->state, !=, RXRPC_CALL_COMPLETE);
531 }
532
533 del_timer_sync(&call->resend_timer);
534 del_timer_sync(&call->ack_timer);
535 del_timer_sync(&call->lifetimer);
536 call->deadspan.expires = jiffies + rxrpc_dead_call_timeout * HZ;
537 add_timer(&call->deadspan);
538
539 _leave("");
540 }
541
542 /*
543 * handle a dead call being ready for reaping
544 */
rxrpc_dead_call_expired(unsigned long _call)545 static void rxrpc_dead_call_expired(unsigned long _call)
546 {
547 struct rxrpc_call *call = (struct rxrpc_call *) _call;
548
549 _enter("{%d}", call->debug_id);
550
551 write_lock_bh(&call->state_lock);
552 call->state = RXRPC_CALL_DEAD;
553 write_unlock_bh(&call->state_lock);
554 rxrpc_put_call(call);
555 }
556
557 /*
558 * mark a call as to be released, aborting it if it's still in progress
559 * - called with softirqs disabled
560 */
rxrpc_mark_call_released(struct rxrpc_call * call)561 static void rxrpc_mark_call_released(struct rxrpc_call *call)
562 {
563 bool sched;
564
565 write_lock(&call->state_lock);
566 if (call->state < RXRPC_CALL_DEAD) {
567 sched = false;
568 if (call->state < RXRPC_CALL_COMPLETE) {
569 _debug("abort call %p", call);
570 call->state = RXRPC_CALL_LOCALLY_ABORTED;
571 call->abort_code = RX_CALL_DEAD;
572 if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
573 sched = true;
574 }
575 if (!test_and_set_bit(RXRPC_CALL_RELEASE, &call->events))
576 sched = true;
577 if (sched)
578 rxrpc_queue_call(call);
579 }
580 write_unlock(&call->state_lock);
581 }
582
583 /*
584 * release all the calls associated with a socket
585 */
rxrpc_release_calls_on_socket(struct rxrpc_sock * rx)586 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
587 {
588 struct rxrpc_call *call;
589 struct rb_node *p;
590
591 _enter("%p", rx);
592
593 read_lock_bh(&rx->call_lock);
594
595 /* mark all the calls as no longer wanting incoming packets */
596 for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
597 call = rb_entry(p, struct rxrpc_call, sock_node);
598 rxrpc_mark_call_released(call);
599 }
600
601 /* kill the not-yet-accepted incoming calls */
602 list_for_each_entry(call, &rx->secureq, accept_link) {
603 rxrpc_mark_call_released(call);
604 }
605
606 list_for_each_entry(call, &rx->acceptq, accept_link) {
607 rxrpc_mark_call_released(call);
608 }
609
610 read_unlock_bh(&rx->call_lock);
611 _leave("");
612 }
613
614 /*
615 * release a call
616 */
__rxrpc_put_call(struct rxrpc_call * call)617 void __rxrpc_put_call(struct rxrpc_call *call)
618 {
619 ASSERT(call != NULL);
620
621 _enter("%p{u=%d}", call, atomic_read(&call->usage));
622
623 ASSERTCMP(atomic_read(&call->usage), >, 0);
624
625 if (atomic_dec_and_test(&call->usage)) {
626 _debug("call %d dead", call->debug_id);
627 ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
628 rxrpc_queue_work(&call->destroyer);
629 }
630 _leave("");
631 }
632
633 /*
634 * clean up a call
635 */
rxrpc_cleanup_call(struct rxrpc_call * call)636 static void rxrpc_cleanup_call(struct rxrpc_call *call)
637 {
638 _net("DESTROY CALL %d", call->debug_id);
639
640 ASSERT(call->socket);
641
642 memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
643
644 del_timer_sync(&call->lifetimer);
645 del_timer_sync(&call->deadspan);
646 del_timer_sync(&call->ack_timer);
647 del_timer_sync(&call->resend_timer);
648
649 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
650 ASSERTCMP(call->events, ==, 0);
651 if (work_pending(&call->processor)) {
652 _debug("defer destroy");
653 rxrpc_queue_work(&call->destroyer);
654 return;
655 }
656
657 if (call->conn) {
658 spin_lock(&call->conn->trans->peer->lock);
659 list_del(&call->error_link);
660 spin_unlock(&call->conn->trans->peer->lock);
661
662 write_lock_bh(&call->conn->lock);
663 rb_erase(&call->conn_node, &call->conn->calls);
664 write_unlock_bh(&call->conn->lock);
665 rxrpc_put_connection(call->conn);
666 }
667
668 if (call->acks_window) {
669 _debug("kill Tx window %d",
670 CIRC_CNT(call->acks_head, call->acks_tail,
671 call->acks_winsz));
672 smp_mb();
673 while (CIRC_CNT(call->acks_head, call->acks_tail,
674 call->acks_winsz) > 0) {
675 struct rxrpc_skb_priv *sp;
676 unsigned long _skb;
677
678 _skb = call->acks_window[call->acks_tail] & ~1;
679 sp = rxrpc_skb((struct sk_buff *) _skb);
680 _debug("+++ clear Tx %u", ntohl(sp->hdr.seq));
681 rxrpc_free_skb((struct sk_buff *) _skb);
682 call->acks_tail =
683 (call->acks_tail + 1) & (call->acks_winsz - 1);
684 }
685
686 kfree(call->acks_window);
687 }
688
689 rxrpc_free_skb(call->tx_pending);
690
691 rxrpc_purge_queue(&call->rx_queue);
692 ASSERT(skb_queue_empty(&call->rx_oos_queue));
693 sock_put(&call->socket->sk);
694 kmem_cache_free(rxrpc_call_jar, call);
695 }
696
697 /*
698 * destroy a call
699 */
rxrpc_destroy_call(struct work_struct * work)700 static void rxrpc_destroy_call(struct work_struct *work)
701 {
702 struct rxrpc_call *call =
703 container_of(work, struct rxrpc_call, destroyer);
704
705 _enter("%p{%d,%d,%p}",
706 call, atomic_read(&call->usage), call->channel, call->conn);
707
708 ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
709
710 write_lock_bh(&rxrpc_call_lock);
711 list_del_init(&call->link);
712 write_unlock_bh(&rxrpc_call_lock);
713
714 rxrpc_cleanup_call(call);
715 _leave("");
716 }
717
718 /*
719 * preemptively destroy all the call records from a transport endpoint rather
720 * than waiting for them to time out
721 */
rxrpc_destroy_all_calls(void)722 void __exit rxrpc_destroy_all_calls(void)
723 {
724 struct rxrpc_call *call;
725
726 _enter("");
727 write_lock_bh(&rxrpc_call_lock);
728
729 while (!list_empty(&rxrpc_calls)) {
730 call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
731 _debug("Zapping call %p", call);
732
733 list_del_init(&call->link);
734
735 switch (atomic_read(&call->usage)) {
736 case 0:
737 ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
738 break;
739 case 1:
740 if (del_timer_sync(&call->deadspan) != 0 &&
741 call->state != RXRPC_CALL_DEAD)
742 rxrpc_dead_call_expired((unsigned long) call);
743 if (call->state != RXRPC_CALL_DEAD)
744 break;
745 default:
746 printk(KERN_ERR "RXRPC:"
747 " Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
748 call, atomic_read(&call->usage),
749 atomic_read(&call->ackr_not_idle),
750 rxrpc_call_states[call->state],
751 call->flags, call->events);
752 if (!skb_queue_empty(&call->rx_queue))
753 printk(KERN_ERR"RXRPC: Rx queue occupied\n");
754 if (!skb_queue_empty(&call->rx_oos_queue))
755 printk(KERN_ERR"RXRPC: OOS queue occupied\n");
756 break;
757 }
758
759 write_unlock_bh(&rxrpc_call_lock);
760 cond_resched();
761 write_lock_bh(&rxrpc_call_lock);
762 }
763
764 write_unlock_bh(&rxrpc_call_lock);
765 _leave("");
766 }
767
768 /*
769 * handle call lifetime being exceeded
770 */
rxrpc_call_life_expired(unsigned long _call)771 static void rxrpc_call_life_expired(unsigned long _call)
772 {
773 struct rxrpc_call *call = (struct rxrpc_call *) _call;
774
775 if (call->state >= RXRPC_CALL_COMPLETE)
776 return;
777
778 _enter("{%d}", call->debug_id);
779 read_lock_bh(&call->state_lock);
780 if (call->state < RXRPC_CALL_COMPLETE) {
781 set_bit(RXRPC_CALL_LIFE_TIMER, &call->events);
782 rxrpc_queue_call(call);
783 }
784 read_unlock_bh(&call->state_lock);
785 }
786
787 /*
788 * handle resend timer expiry
789 * - may not take call->state_lock as this can deadlock against del_timer_sync()
790 */
rxrpc_resend_time_expired(unsigned long _call)791 static void rxrpc_resend_time_expired(unsigned long _call)
792 {
793 struct rxrpc_call *call = (struct rxrpc_call *) _call;
794
795 _enter("{%d}", call->debug_id);
796
797 if (call->state >= RXRPC_CALL_COMPLETE)
798 return;
799
800 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
801 if (!test_and_set_bit(RXRPC_CALL_RESEND_TIMER, &call->events))
802 rxrpc_queue_call(call);
803 }
804
805 /*
806 * handle ACK timer expiry
807 */
rxrpc_ack_time_expired(unsigned long _call)808 static void rxrpc_ack_time_expired(unsigned long _call)
809 {
810 struct rxrpc_call *call = (struct rxrpc_call *) _call;
811
812 _enter("{%d}", call->debug_id);
813
814 if (call->state >= RXRPC_CALL_COMPLETE)
815 return;
816
817 read_lock_bh(&call->state_lock);
818 if (call->state < RXRPC_CALL_COMPLETE &&
819 !test_and_set_bit(RXRPC_CALL_ACK, &call->events))
820 rxrpc_queue_call(call);
821 read_unlock_bh(&call->state_lock);
822 }
823