summaryrefslogtreecommitdiff
path: root/net/rxrpc/ar-call.c
blob: bf656c230ba93e2dee0cf5c17ec403f84f09a4b2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
/* RxRPC individual remote procedure call handling
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/circ_buf.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"

const char *const rxrpc_call_states[] = {
	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
	[RXRPC_CALL_CLIENT_RECV_REPLY]		= "ClRcvRpl",
	[RXRPC_CALL_CLIENT_FINAL_ACK]		= "ClFnlACK",
	[RXRPC_CALL_SERVER_SECURING]		= "SvSecure",
	[RXRPC_CALL_SERVER_ACCEPTING]		= "SvAccept",
	[RXRPC_CALL_SERVER_RECV_REQUEST]	= "SvRcvReq",
	[RXRPC_CALL_SERVER_ACK_REQUEST]		= "SvAckReq",
	[RXRPC_CALL_SERVER_SEND_REPLY]		= "SvSndRpl",
	[RXRPC_CALL_SERVER_AWAIT_ACK]		= "SvAwtACK",
	[RXRPC_CALL_COMPLETE]			= "Complete",
	[RXRPC_CALL_SERVER_BUSY]		= "SvBusy  ",
	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
	[RXRPC_CALL_DEAD]			= "Dead    ",
};

struct kmem_cache *rxrpc_call_jar;
LIST_HEAD(rxrpc_calls);
DEFINE_RWLOCK(rxrpc_call_lock);
static unsigned rxrpc_call_max_lifetime = 60;
static unsigned rxrpc_dead_call_timeout = 2;

static void rxrpc_destroy_call(struct work_struct *work);
static void rxrpc_call_life_expired(unsigned long _call);
static void rxrpc_dead_call_expired(unsigned long _call);
static void rxrpc_ack_time_expired(unsigned long _call);
static void rxrpc_resend_time_expired(unsigned long _call);

/*
 * allocate a new call
 */
static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
{
	struct rxrpc_call *call;

	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
	if (!call)
		return NULL;

	call->acks_winsz = 16;
	call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
				    gfp);
	if (!call->acks_window) {
		kmem_cache_free(rxrpc_call_jar, call);
		return NULL;
	}

	setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
		    (unsigned long) call);
	setup_timer(&call->deadspan, &rxrpc_dead_call_expired,
		    (unsigned long) call);
	setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
		    (unsigned long) call);
	setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
		    (unsigned long) call);
	INIT_WORK(&call->destroyer, &rxrpc_destroy_call);
	INIT_WORK(&call->processor, &rxrpc_process_call);
	INIT_LIST_HEAD(&call->accept_link);
	skb_queue_head_init(&call->rx_queue);
	skb_queue_head_init(&call->rx_oos_queue);
	init_waitqueue_head(&call->tx_waitq);
	spin_lock_init(&call->lock);
	rwlock_init(&call->state_lock);
	atomic_set(&call->usage, 1);
	call->debug_id = atomic_inc_return(&rxrpc_debug_id);
	call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;

	memset(&call->sock_node, 0xed, sizeof(call->sock_node));

	call->rx_data_expect = 1;
	call->rx_data_eaten = 0;
	call->rx_first_oos = 0;
	call->ackr_win_top = call->rx_data_eaten + 1 + RXRPC_MAXACKS;
	call->creation_jif = jiffies;
	return call;
}

/*
 * allocate a new client call and attempt to get a connection slot for it
 */
static struct rxrpc_call *rxrpc_alloc_client_call(
	struct rxrpc_sock *rx,
	struct rxrpc_transport *trans,
	struct rxrpc_conn_bundle *bundle,
	gfp_t gfp)
{
	struct rxrpc_call *call;
	int ret;

	_enter("");

	ASSERT(rx != NULL);
	ASSERT(trans != NULL);
	ASSERT(bundle != NULL);

	call = rxrpc_alloc_call(gfp);
	if (!call)
		return ERR_PTR(-ENOMEM);

	sock_hold(&rx->sk);
	call->socket = rx;
	call->rx_data_post = 1;

	ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
	if (ret < 0) {
		kmem_cache_free(rxrpc_call_jar, call);
		return ERR_PTR(ret);
	}

	spin_lock(&call->conn->trans->peer->lock);
	list_add(&call->error_link, &call->conn->trans->peer->error_targets);
	spin_unlock(&call->conn->trans->peer->lock);

	call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
	add_timer(&call->lifetimer);

	_leave(" = %p", call);
	return call;
}

/*
 * set up a call for the given data
 * - called in process context with IRQs enabled
 */
struct rxrpc_call *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)
{
	struct rxrpc_call *call, *candidate;
	struct rb_node *p, *parent, **pp;

	_enter("%p,%d,%d,%lx,%d",
	       rx, trans ? trans->debug_id : -1, bundle ? bundle->debug_id : -1,
	       user_call_ID, create);

	/* search the extant calls first for one that matches the specified
	 * user ID */
	read_lock(&rx->call_lock);

	p = rx->calls.rb_node;
	while (p) {
		call = rb_entry(p, struct rxrpc_call, sock_node);

		if (user_call_ID < call->user_call_ID)
			p = p->rb_left;
		else if (user_call_ID > call->user_call_ID)
			p = p->rb_right;
		else
			goto found_extant_call;
	}

	read_unlock(&rx->call_lock);

	if (!create || !trans)
		return ERR_PTR(-EBADSLT);

	/* not yet present - create a candidate for a new record and then
	 * redo the search */
	candidate = rxrpc_alloc_client_call(rx, trans, bundle, gfp);
	if (IS_ERR(candidate)) {
		_leave(" = %ld", PTR_ERR(candidate));
		return candidate;
	}

	candidate->user_call_ID = user_call_ID;
	__set_bit(RXRPC_CALL_HAS_USERID, &candidate->flags);

	write_lock(&rx->call_lock);

	pp = &rx->calls.rb_node;
	parent = NULL;
	while (*pp) {
		parent = *pp;
		call = rb_entry(parent, struct rxrpc_call, sock_node);

		if (user_call_ID < call->user_call_ID)
			pp = &(*pp)->rb_left;
		else if (user_call_ID > call->user_call_ID)
			pp = &(*pp)->rb_right;
		else
			goto found_extant_second;
	}

	/* second search also failed; add the new call */
	call = candidate;
	candidate = NULL;
	rxrpc_get_call(call);

	rb_link_node(&call->sock_node, parent, pp);
	rb_insert_color(&call->sock_node, &rx->calls);
	write_unlock(&rx->call_lock);

	write_lock_bh(&rxrpc_call_lock);
	list_add_tail(&call->link, &rxrpc_calls);
	write_unlock_bh(&rxrpc_call_lock);

	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);

	_leave(" = %p [new]", call);
	return call;

	/* we found the call in the list immediately */
found_extant_call:
	rxrpc_get_call(call);
	read_unlock(&rx->call_lock);
	_leave(" = %p [extant %d]", call, atomic_read(&call->usage));
	return call;

	/* we found the call on the second time through the list */
found_extant_second:
	rxrpc_get_call(call);
	write_unlock(&rx->call_lock);
	rxrpc_put_call(candidate);
	_leave(" = %p [second %d]", call, atomic_read(&call->usage));
	return call;
}

/*
 * set up an incoming call
 * - called in process context with IRQs enabled
 */
struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
				       struct rxrpc_connection *conn,
				       struct rxrpc_header *hdr,
				       gfp_t gfp)
{
	struct rxrpc_call *call, *candidate;
	struct rb_node **p, *parent;
	__be32 call_id;

	_enter(",%d,,%x", conn->debug_id, gfp);

	ASSERT(rx != NULL);

	candidate = rxrpc_alloc_call(gfp);
	if (!candidate)
		return ERR_PTR(-EBUSY);

	candidate->socket = rx;
	candidate->conn = conn;
	candidate->cid = hdr->cid;
	candidate->call_id = hdr->callNumber;
	candidate->channel = ntohl(hdr->cid) & RXRPC_CHANNELMASK;
	candidate->rx_data_post = 0;
	candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
	if (conn->security_ix > 0)
		candidate->state = RXRPC_CALL_SERVER_SECURING;

	write_lock_bh(&conn->lock);

	/* set the channel for this call */
	call = conn->channels[candidate->channel];
	_debug("channel[%u] is %p", candidate->channel, call);
	if (call && call->call_id == hdr->callNumber) {
		/* already set; must've been a duplicate packet */
		_debug("extant call [%d]", call->state);
		ASSERTCMP(call->conn, ==, conn);

		read_lock(&call->state_lock);
		switch (call->state) {
		case RXRPC_CALL_LOCALLY_ABORTED:
			if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
				rxrpc_queue_call(call);
		case RXRPC_CALL_REMOTELY_ABORTED:
			read_unlock(&call->state_lock);
			goto aborted_call;
		default:
			rxrpc_get_call(call);
			read_unlock(&call->state_lock);
			goto extant_call;
		}
	}

	if (call) {
		/* it seems the channel is still in use from the previous call
		 * - ditch the old binding if its call is now complete */
		_debug("CALL: %u { %s }",
		       call->debug_id, rxrpc_call_states[call->state]);

		if (call->state >= RXRPC_CALL_COMPLETE) {
			conn->channels[call->channel] = NULL;
		} else {
			write_unlock_bh(&conn->lock);
			kmem_cache_free(rxrpc_call_jar, candidate);
			_leave(" = -EBUSY");
			return ERR_PTR(-EBUSY);
		}
	}

	/* check the call number isn't duplicate */
	_debug("check dup");
	call_id = hdr->callNumber;
	p = &conn->calls.rb_node;
	parent = NULL;
	while (*p) {
		parent = *p;
		call = rb_entry(parent, struct rxrpc_call, conn_node);

		if (call_id < call->call_id)
			p = &(*p)->rb_left;
		else if (call_id > call->call_id)
			p = &(*p)->rb_right;
		else
			goto old_call;
	}

	/* make the call available */
	_debug("new call");
	call = candidate;
	candidate = NULL;
	rb_link_node(&call->conn_node, parent, p);
	rb_insert_color(&call->conn_node, &conn->calls);
	conn->channels[call->channel] = call;
	sock_hold(&rx->sk);
	atomic_inc(&conn->usage);
	write_unlock_bh(&conn->lock);

	spin_lock(&conn->trans->peer->lock);
	list_add(&call->error_link, &conn->trans->peer->error_targets);
	spin_unlock(&conn->trans->peer->lock);

	write_lock_bh(&rxrpc_call_lock);
	list_add_tail(&call->link, &rxrpc_calls);
	write_unlock_bh(&rxrpc_call_lock);

	_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);

	call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
	add_timer(&call->lifetimer);
	_leave(" = %p {%d} [new]", call, call->debug_id);
	return call;

extant_call:
	write_unlock_bh(&conn->lock);
	kmem_cache_free(rxrpc_call_jar, candidate);
	_leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
	return call;

aborted_call:
	write_unlock_bh(&conn->lock);
	kmem_cache_free(rxrpc_call_jar, candidate);
	_leave(" = -ECONNABORTED");
	return ERR_PTR(-ECONNABORTED);

old_call:
	write_unlock_bh(&conn->lock);
	kmem_cache_free(rxrpc_call_jar, candidate);
	_leave(" = -ECONNRESET [old]");
	return ERR_PTR(-ECONNRESET);
}

/*
 * find an extant server call
 * - called in process context with IRQs enabled
 */
struct rxrpc_call *rxrpc_find_server_call(struct rxrpc_sock *rx,
					  unsigned long user_call_ID)
{
	struct rxrpc_call *call;
	struct rb_node *p;

	_enter("%p,%lx", rx, user_call_ID);

	/* search the extant calls for one that matches the specified user
	 * ID */
	read_lock(&rx->call_lock);

	p = rx->calls.rb_node;
	while (p) {
		call = rb_entry(p, struct rxrpc_call, sock_node);

		if (user_call_ID < call->user_call_ID)
			p = p->rb_left;
		else if (user_call_ID > call->user_call_ID)
			p = p->rb_right;
		else
			goto found_extant_call;
	}

	read_unlock(&rx->call_lock);
	_leave(" = NULL");
	return NULL;

	/* we found the call in the list immediately */
found_extant_call:
	rxrpc_get_call(call);
	read_unlock(&rx->call_lock);
	_leave(" = %p [%d]", call, atomic_read(&call->usage));
	return call;
}

/*
 * detach a call from a socket and set up for release
 */
void rxrpc_release_call(struct rxrpc_call *call)
{
	struct rxrpc_connection *conn = call->conn;
	struct rxrpc_sock *rx = call->socket;

	_enter("{%d,%d,%d,%d}",
	       call->debug_id, atomic_read(&call->usage),
	       atomic_read(&call->ackr_not_idle),
	       call->rx_first_oos);

	spin_lock_bh(&call->lock);
	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
		BUG();
	spin_unlock_bh(&call->lock);

	/* dissociate from the socket
	 * - the socket's ref on the call is passed to the death timer
	 */
	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);

	write_lock_bh(&rx->call_lock);
	if (!list_empty(&call->accept_link)) {
		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
		       call, call->events, call->flags);
		ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
		list_del_init(&call->accept_link);
		sk_acceptq_removed(&rx->sk);
	} else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
		rb_erase(&call->sock_node, &rx->calls);
		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
		clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
	}
	write_unlock_bh(&rx->call_lock);

	/* free up the channel for reuse */
	spin_lock(&conn->trans->client_lock);
	write_lock_bh(&conn->lock);
	write_lock(&call->state_lock);

	if (conn->channels[call->channel] == call)
		conn->channels[call->channel] = NULL;

	if (conn->out_clientflag && conn->bundle) {
		conn->avail_calls++;
		switch (conn->avail_calls) {
		case 1:
			list_move_tail(&conn->bundle_link,
				       &conn->bundle->avail_conns);
		case 2 ... RXRPC_MAXCALLS - 1:
			ASSERT(conn->channels[0] == NULL ||
			       conn->channels[1] == NULL ||
			       conn->channels[2] == NULL ||
			       conn->channels[3] == NULL);
			break;
		case RXRPC_MAXCALLS:
			list_move_tail(&conn->bundle_link,
				       &conn->bundle->unused_conns);
			ASSERT(conn->channels[0] == NULL &&
			       conn->channels[1] == NULL &&
			       conn->channels[2] == NULL &&
			       conn->channels[3] == NULL);
			break;
		default:
			printk(KERN_ERR "RxRPC: conn->avail_calls=%d\n",
			       conn->avail_calls);
			BUG();
		}
	}

	spin_unlock(&conn->trans->client_lock);

	if (call->state < RXRPC_CALL_COMPLETE &&
	    call->state != RXRPC_CALL_CLIENT_FINAL_ACK) {
		_debug("+++ ABORTING STATE %d +++\n", call->state);
		call->state = RXRPC_CALL_LOCALLY_ABORTED;
		call->abort_code = RX_CALL_DEAD;
		set_bit(RXRPC_CALL_ABORT, &call->events);
		rxrpc_queue_call(call);
	}
	write_unlock(&call->state_lock);
	write_unlock_bh(&conn->lock);

	/* clean up the Rx queue */
	if (!skb_queue_empty(&call->rx_queue) ||
	    !skb_queue_empty(&call->rx_oos_queue)) {
		struct rxrpc_skb_priv *sp;
		struct sk_buff *skb;

		_debug("purge Rx queues");

		spin_lock_bh(&call->lock);
		while ((skb = skb_dequeue(&call->rx_queue)) ||
		       (skb = skb_dequeue(&call->rx_oos_queue))) {
			sp = rxrpc_skb(skb);
			if (sp->call) {
				ASSERTCMP(sp->call, ==, call);
				rxrpc_put_call(call);
				sp->call = NULL;
			}
			skb->destructor = NULL;
			spin_unlock_bh(&call->lock);

			_debug("- zap %s %%%u #%u",
			       rxrpc_pkts[sp->hdr.type],
			       ntohl(sp->hdr.serial),
			       ntohl(sp->hdr.seq));
			rxrpc_free_skb(skb);
			spin_lock_bh(&call->lock);
		}
		spin_unlock_bh(&call->lock);

		ASSERTCMP(call->state, !=, RXRPC_CALL_COMPLETE);
	}

	del_timer_sync(&call->resend_timer);
	del_timer_sync(&call->ack_timer);
	del_timer_sync(&call->lifetimer);
	call->deadspan.expires = jiffies + rxrpc_dead_call_timeout * HZ;
	add_timer(&call->deadspan);

	_leave("");
}

/*
 * handle a dead call being ready for reaping
 */
static void rxrpc_dead_call_expired(unsigned long _call)
{
	struct rxrpc_call *call = (struct rxrpc_call *) _call;

	_enter("{%d}", call->debug_id);

	write_lock_bh(&call->state_lock);
	call->state = RXRPC_CALL_DEAD;
	write_unlock_bh(&call->state_lock);
	rxrpc_put_call(call);
}

/*
 * mark a call as to be released, aborting it if it's still in progress
 * - called with softirqs disabled
 */
static void rxrpc_mark_call_released(struct rxrpc_call *call)
{
	bool sched;

	write_lock(&call->state_lock);
	if (call->state < RXRPC_CALL_DEAD) {
		sched = false;
		if (call->state < RXRPC_CALL_COMPLETE) {
			_debug("abort call %p", call);
			call->state = RXRPC_CALL_LOCALLY_ABORTED;
			call->abort_code = RX_CALL_DEAD;
			if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
				sched = true;
		}
		if (!test_and_set_bit(RXRPC_CALL_RELEASE, &call->events))
			sched = true;
		if (sched)
			rxrpc_queue_call(call);
	}
	write_unlock(&call->state_lock);
}

/*
 * release all the calls associated with a socket
 */
void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
{
	struct rxrpc_call *call;
	struct rb_node *p;

	_enter("%p", rx);

	read_lock_bh(&rx->call_lock);

	/* mark all the calls as no longer wanting incoming packets */
	for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
		call = rb_entry(p, struct rxrpc_call, sock_node);
		rxrpc_mark_call_released(call);
	}

	/* kill the not-yet-accepted incoming calls */
	list_for_each_entry(call, &rx->secureq, accept_link) {
		rxrpc_mark_call_released(call);
	}

	list_for_each_entry(call, &rx->acceptq, accept_link) {
		rxrpc_mark_call_released(call);
	}

	read_unlock_bh(&rx->call_lock);
	_leave("");
}

/*
 * release a call
 */
void __rxrpc_put_call(struct rxrpc_call *call)
{
	ASSERT(call != NULL);

	_enter("%p{u=%d}", call, atomic_read(&call->usage));

	ASSERTCMP(atomic_read(&call->usage), >, 0);

	if (atomic_dec_and_test(&call->usage)) {
		_debug("call %d dead", call->debug_id);
		ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
		rxrpc_queue_work(&call->destroyer);
	}
	_leave("");
}

/*
 * clean up a call
 */
static void rxrpc_cleanup_call(struct rxrpc_call *call)
{
	_net("DESTROY CALL %d", call->debug_id);

	ASSERT(call->socket);

	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));

	del_timer_sync(&call->lifetimer);
	del_timer_sync(&call->deadspan);
	del_timer_sync(&call->ack_timer);
	del_timer_sync(&call->resend_timer);

	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
	ASSERTCMP(call->events, ==, 0);
	if (work_pending(&call->processor)) {
		_debug("defer destroy");
		rxrpc_queue_work(&call->destroyer);
		return;
	}

	if (call->conn) {
		spin_lock(&call->conn->trans->peer->lock);
		list_del(&call->error_link);
		spin_unlock(&call->conn->trans->peer->lock);

		write_lock_bh(&call->conn->lock);
		rb_erase(&call->conn_node, &call->conn->calls);
		write_unlock_bh(&call->conn->lock);
		rxrpc_put_connection(call->conn);
	}

	if (call->acks_window) {
		_debug("kill Tx window %d",
		       CIRC_CNT(call->acks_head, call->acks_tail,
				call->acks_winsz));
		smp_mb();
		while (CIRC_CNT(call->acks_head, call->acks_tail,
				call->acks_winsz) > 0) {
			struct rxrpc_skb_priv *sp;
			unsigned long _skb;

			_skb = call->acks_window[call->acks_tail] & ~1;
			sp = rxrpc_skb((struct sk_buff *) _skb);
			_debug("+++ clear Tx %u", ntohl(sp->hdr.seq));
			rxrpc_free_skb((struct sk_buff *) _skb);
			call->acks_tail =
				(call->acks_tail + 1) & (call->acks_winsz - 1);
		}

		kfree(call->acks_window);
	}

	rxrpc_free_skb(call->tx_pending);

	rxrpc_purge_queue(&call->rx_queue);
	ASSERT(skb_queue_empty(&call->rx_oos_queue));
	sock_put(&call->socket->sk);
	kmem_cache_free(rxrpc_call_jar, call);
}

/*
 * destroy a call
 */
static void rxrpc_destroy_call(struct work_struct *work)
{
	struct rxrpc_call *call =
		container_of(work, struct rxrpc_call, destroyer);

	_enter("%p{%d,%d,%p}",
	       call, atomic_read(&call->usage), call->channel, call->conn);

	ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);

	write_lock_bh(&rxrpc_call_lock);
	list_del_init(&call->link);
	write_unlock_bh(&rxrpc_call_lock);

	rxrpc_cleanup_call(call);
	_leave("");
}

/*
 * preemptively destroy all the call records from a transport endpoint rather
 * than waiting for them to time out
 */
void __exit rxrpc_destroy_all_calls(void)
{
	struct rxrpc_call *call;

	_enter("");
	write_lock_bh(&rxrpc_call_lock);

	while (!list_empty(&rxrpc_calls)) {
		call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
		_debug("Zapping call %p", call);

		list_del_init(&call->link);

		switch (atomic_read(&call->usage)) {
		case 0:
			ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
			break;
		case 1:
			if (del_timer_sync(&call->deadspan) != 0 &&
			    call->state != RXRPC_CALL_DEAD)
				rxrpc_dead_call_expired((unsigned long) call);
			if (call->state != RXRPC_CALL_DEAD)
				break;
		default:
			printk(KERN_ERR "RXRPC:"
			       " Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
			       call, atomic_read(&call->usage),
			       atomic_read(&call->ackr_not_idle),
			       rxrpc_call_states[call->state],
			       call->flags, call->events);
			if (!skb_queue_empty(&call->rx_queue))
				printk(KERN_ERR"RXRPC: Rx queue occupied\n");
			if (!skb_queue_empty(&call->rx_oos_queue))
				printk(KERN_ERR"RXRPC: OOS queue occupied\n");
			break;
		}

		write_unlock_bh(&rxrpc_call_lock);
		cond_resched();
		write_lock_bh(&rxrpc_call_lock);
	}

	write_unlock_bh(&rxrpc_call_lock);
	_leave("");
}

/*
 * handle call lifetime being exceeded
 */
static void rxrpc_call_life_expired(unsigned long _call)
{
	struct rxrpc_call *call = (struct rxrpc_call *) _call;

	if (call->state >= RXRPC_CALL_COMPLETE)
		return;

	_enter("{%d}", call->debug_id);
	read_lock_bh(&call->state_lock);
	if (call->state < RXRPC_CALL_COMPLETE) {
		set_bit(RXRPC_CALL_LIFE_TIMER, &call->events);
		rxrpc_queue_call(call);
	}
	read_unlock_bh(&call->state_lock);
}

/*
 * handle resend timer expiry
 * - may not take call->state_lock as this can deadlock against del_timer_sync()
 */
static void rxrpc_resend_time_expired(unsigned long _call)
{
	struct rxrpc_call *call = (struct rxrpc_call *) _call;

	_enter("{%d}", call->debug_id);

	if (call->state >= RXRPC_CALL_COMPLETE)
		return;

	clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
	if (!test_and_set_bit(RXRPC_CALL_RESEND_TIMER, &call->events))
		rxrpc_queue_call(call);
}

/*
 * handle ACK timer expiry
 */
static void rxrpc_ack_time_expired(unsigned long _call)
{
	struct rxrpc_call *call = (struct rxrpc_call *) _call;

	_enter("{%d}", call->debug_id);

	if (call->state >= RXRPC_CALL_COMPLETE)
		return;

	read_lock_bh(&call->state_lock);
	if (call->state < RXRPC_CALL_COMPLETE &&
	    !test_and_set_bit(RXRPC_CALL_ACK, &call->events))
		rxrpc_queue_call(call);
	read_unlock_bh(&call->state_lock);
}