summaryrefslogtreecommitdiff
path: root/net/rxrpc/call_object.c
blob: f9e983a12c1492261d87773b5a118431dafd406f (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
// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC individual remote procedure call handling
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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

const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
	[RXRPC_CALL_UNINITIALISED]		= "Uninit  ",
	[RXRPC_CALL_CLIENT_AWAIT_CONN]		= "ClWtConn",
	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
	[RXRPC_CALL_CLIENT_RECV_REPLY]		= "ClRcvRpl",
	[RXRPC_CALL_SERVER_PREALLOC]		= "SvPrealc",
	[RXRPC_CALL_SERVER_SECURING]		= "SvSecure",
	[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",
};

const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
	[RXRPC_CALL_SUCCEEDED]			= "Complete",
	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
	[RXRPC_CALL_LOCAL_ERROR]		= "LocError",
	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
};

struct kmem_cache *rxrpc_call_jar;

static DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000);
static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000);

void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
{
	struct rxrpc_local *local = call->local;
	bool busy;

	if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
		spin_lock_bh(&local->lock);
		busy = !list_empty(&call->attend_link);
		trace_rxrpc_poke_call(call, busy, what);
		if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
			busy = true;
		if (!busy) {
			list_add_tail(&call->attend_link, &local->call_attend_q);
		}
		spin_unlock_bh(&local->lock);
		if (!busy)
			rxrpc_wake_up_io_thread(local);
	}
}

static void rxrpc_call_timer_expired(struct timer_list *t)
{
	struct rxrpc_call *call = from_timer(call, t, timer);

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

	if (!__rxrpc_call_is_complete(call)) {
		trace_rxrpc_timer_expired(call);
		rxrpc_poke_call(call, rxrpc_call_poke_timer);
	}
}

static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;

static void rxrpc_destroy_call(struct work_struct *);

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

	_enter("%p,%lx", rx, user_call_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;

found_extant_call:
	rxrpc_get_call(call, rxrpc_call_get_sendmsg);
	read_unlock(&rx->call_lock);
	_leave(" = %p [%d]", call, refcount_read(&call->ref));
	return call;
}

/*
 * allocate a new call
 */
struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
				    unsigned int debug_id)
{
	struct rxrpc_call *call;
	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));

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

	mutex_init(&call->user_mutex);

	/* Prevent lockdep reporting a deadlock false positive between the afs
	 * filesystem and sys_sendmsg() via the mmap sem.
	 */
	if (rx->sk.sk_kern_sock)
		lockdep_set_class(&call->user_mutex,
				  &rxrpc_call_user_mutex_lock_class_key);

	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
	INIT_WORK(&call->destroyer, rxrpc_destroy_call);
	INIT_LIST_HEAD(&call->link);
	INIT_LIST_HEAD(&call->wait_link);
	INIT_LIST_HEAD(&call->accept_link);
	INIT_LIST_HEAD(&call->recvmsg_link);
	INIT_LIST_HEAD(&call->sock_link);
	INIT_LIST_HEAD(&call->attend_link);
	INIT_LIST_HEAD(&call->tx_sendmsg);
	INIT_LIST_HEAD(&call->tx_buffer);
	skb_queue_head_init(&call->recvmsg_queue);
	skb_queue_head_init(&call->rx_oos_queue);
	init_waitqueue_head(&call->waitq);
	spin_lock_init(&call->notify_lock);
	spin_lock_init(&call->tx_lock);
	refcount_set(&call->ref, 1);
	call->debug_id		= debug_id;
	call->tx_total_len	= -1;
	call->next_rx_timo	= 20 * HZ;
	call->next_req_timo	= 1 * HZ;
	call->ackr_window	= 1;
	call->ackr_wtop		= 1;
	call->delay_ack_at	= KTIME_MAX;
	call->ack_lost_at	= KTIME_MAX;
	call->resend_at		= KTIME_MAX;
	call->ping_at		= KTIME_MAX;
	call->keepalive_at	= KTIME_MAX;
	call->expect_rx_by	= KTIME_MAX;
	call->expect_req_by	= KTIME_MAX;
	call->expect_term_by	= KTIME_MAX;

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

	call->rx_winsize = rxrpc_rx_window_size;
	call->tx_winsize = 16;

	call->cong_cwnd = RXRPC_MIN_CWND;
	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;

	call->rxnet = rxnet;
	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
	atomic_inc(&rxnet->nr_calls);
	return call;
}

/*
 * Allocate a new client call.
 */
static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
						  struct rxrpc_conn_parameters *cp,
						  struct rxrpc_call_params *p,
						  gfp_t gfp,
						  unsigned int debug_id)
{
	struct rxrpc_call *call;
	ktime_t now;
	int ret;

	_enter("");

	call = rxrpc_alloc_call(rx, gfp, debug_id);
	if (!call)
		return ERR_PTR(-ENOMEM);
	now = ktime_get_real();
	call->acks_latest_ts	= now;
	call->cong_tstamp	= now;
	call->dest_srx		= cp->peer->srx;
	call->dest_srx.srx_service = cp->service_id;
	call->interruptibility	= p->interruptibility;
	call->tx_total_len	= p->tx_total_len;
	call->key		= key_get(cp->key);
	call->peer		= rxrpc_get_peer(cp->peer, rxrpc_peer_get_call);
	call->local		= rxrpc_get_local(cp->local, rxrpc_local_get_call);
	call->security_level	= cp->security_level;
	if (p->kernel)
		__set_bit(RXRPC_CALL_KERNEL, &call->flags);
	if (cp->upgrade)
		__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
	if (cp->exclusive)
		__set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);

	if (p->timeouts.normal)
		call->next_rx_timo = min(p->timeouts.normal, 1);
	if (p->timeouts.idle)
		call->next_req_timo = min(p->timeouts.idle, 1);
	if (p->timeouts.hard)
		call->hard_timo = p->timeouts.hard;

	ret = rxrpc_init_client_call_security(call);
	if (ret < 0) {
		rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
		rxrpc_put_call(call, rxrpc_call_put_discard_error);
		return ERR_PTR(ret);
	}

	rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);

	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
			 p->user_call_ID, rxrpc_call_new_client);

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

/*
 * Initiate the call ack/resend/expiry timer.
 */
void rxrpc_start_call_timer(struct rxrpc_call *call)
{
	if (call->hard_timo) {
		ktime_t delay = ms_to_ktime(call->hard_timo * 1000);

		call->expect_term_by = ktime_add(ktime_get_real(), delay);
		trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
	}
	call->timer.expires = jiffies;
}

/*
 * Wait for a call slot to become available.
 */
static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
{
	struct semaphore *limiter = &rxrpc_call_limiter;

	if (p->kernel)
		limiter = &rxrpc_kernel_call_limiter;
	if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
		down(limiter);
		return limiter;
	}
	return down_interruptible(limiter) < 0 ? NULL : limiter;
}

/*
 * Release a call slot.
 */
static void rxrpc_put_call_slot(struct rxrpc_call *call)
{
	struct semaphore *limiter = &rxrpc_call_limiter;

	if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
		limiter = &rxrpc_kernel_call_limiter;
	up(limiter);
}

/*
 * Start the process of connecting a call.  We obtain a peer and a connection
 * bundle, but the actual association of a call with a connection is offloaded
 * to the I/O thread to simplify locking.
 */
static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
{
	struct rxrpc_local *local = call->local;
	int ret = -ENOMEM;

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

	ret = rxrpc_look_up_bundle(call, gfp);
	if (ret < 0)
		goto error;

	trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
	rxrpc_get_call(call, rxrpc_call_get_io_thread);
	spin_lock(&local->client_call_lock);
	list_add_tail(&call->wait_link, &local->new_client_calls);
	spin_unlock(&local->client_call_lock);
	rxrpc_wake_up_io_thread(local);
	return 0;

error:
	__set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
	return ret;
}

/*
 * Set up a call for the given parameters.
 * - Called with the socket lock held, which it must release.
 * - If it returns a call, the call's lock will need releasing by the caller.
 */
struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
					 struct rxrpc_conn_parameters *cp,
					 struct rxrpc_call_params *p,
					 gfp_t gfp,
					 unsigned int debug_id)
	__releases(&rx->sk.sk_lock.slock)
	__acquires(&call->user_mutex)
{
	struct rxrpc_call *call, *xcall;
	struct rxrpc_net *rxnet;
	struct semaphore *limiter;
	struct rb_node *parent, **pp;
	int ret;

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

	if (WARN_ON_ONCE(!cp->peer)) {
		release_sock(&rx->sk);
		return ERR_PTR(-EIO);
	}

	limiter = rxrpc_get_call_slot(p, gfp);
	if (!limiter) {
		release_sock(&rx->sk);
		return ERR_PTR(-ERESTARTSYS);
	}

	call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id);
	if (IS_ERR(call)) {
		release_sock(&rx->sk);
		up(limiter);
		_leave(" = %ld", PTR_ERR(call));
		return call;
	}

	/* We need to protect a partially set up call against the user as we
	 * will be acting outside the socket lock.
	 */
	mutex_lock(&call->user_mutex);

	/* Publish the call, even though it is incompletely set up as yet */
	write_lock(&rx->call_lock);

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

		if (p->user_call_ID < xcall->user_call_ID)
			pp = &(*pp)->rb_left;
		else if (p->user_call_ID > xcall->user_call_ID)
			pp = &(*pp)->rb_right;
		else
			goto error_dup_user_ID;
	}

	rcu_assign_pointer(call->socket, rx);
	call->user_call_ID = p->user_call_ID;
	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
	rxrpc_get_call(call, rxrpc_call_get_userid);
	rb_link_node(&call->sock_node, parent, pp);
	rb_insert_color(&call->sock_node, &rx->calls);
	list_add(&call->sock_link, &rx->sock_calls);

	write_unlock(&rx->call_lock);

	rxnet = call->rxnet;
	spin_lock(&rxnet->call_lock);
	list_add_tail_rcu(&call->link, &rxnet->calls);
	spin_unlock(&rxnet->call_lock);

	/* From this point on, the call is protected by its own lock. */
	release_sock(&rx->sk);

	/* Set up or get a connection record and set the protocol parameters,
	 * including channel number and call ID.
	 */
	ret = rxrpc_connect_call(call, gfp);
	if (ret < 0)
		goto error_attached_to_socket;

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

	/* We unexpectedly found the user ID in the list after taking
	 * the call_lock.  This shouldn't happen unless the user races
	 * with itself and tries to add the same user ID twice at the
	 * same time in different threads.
	 */
error_dup_user_ID:
	write_unlock(&rx->call_lock);
	release_sock(&rx->sk);
	rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
			 rxrpc_call_see_userid_exists);
	mutex_unlock(&call->user_mutex);
	rxrpc_put_call(call, rxrpc_call_put_userid_exists);
	_leave(" = -EEXIST");
	return ERR_PTR(-EEXIST);

	/* We got an error, but the call is attached to the socket and is in
	 * need of release.  However, we might now race with recvmsg() when it
	 * completion notifies the socket.  Return 0 from sys_sendmsg() and
	 * leave the error to recvmsg() to deal with.
	 */
error_attached_to_socket:
	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
			 rxrpc_call_see_connect_failed);
	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
	_leave(" = c=%08x [err]", call->debug_id);
	return call;
}

/*
 * Set up an incoming call.  call->conn points to the connection.
 * This is called in BH context and isn't allowed to fail.
 */
void rxrpc_incoming_call(struct rxrpc_sock *rx,
			 struct rxrpc_call *call,
			 struct sk_buff *skb)
{
	struct rxrpc_connection *conn = call->conn;
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
	u32 chan;

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

	rcu_assign_pointer(call->socket, rx);
	call->call_id		= sp->hdr.callNumber;
	call->dest_srx.srx_service = sp->hdr.serviceId;
	call->cid		= sp->hdr.cid;
	call->cong_tstamp	= skb->tstamp;

	__set_bit(RXRPC_CALL_EXPOSED, &call->flags);
	rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);

	spin_lock(&conn->state_lock);

	switch (conn->state) {
	case RXRPC_CONN_SERVICE_UNSECURED:
	case RXRPC_CONN_SERVICE_CHALLENGING:
		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
		break;
	case RXRPC_CONN_SERVICE:
		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
		break;

	case RXRPC_CONN_ABORTED:
		rxrpc_set_call_completion(call, conn->completion,
					  conn->abort_code, conn->error);
		break;
	default:
		BUG();
	}

	rxrpc_get_call(call, rxrpc_call_get_io_thread);

	/* Set the channel for this call.  We don't get channel_lock as we're
	 * only defending against the data_ready handler (which we're called
	 * from) and the RESPONSE packet parser (which is only really
	 * interested in call_counter and can cope with a disagreement with the
	 * call pointer).
	 */
	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
	conn->channels[chan].call_counter = call->call_id;
	conn->channels[chan].call_id = call->call_id;
	conn->channels[chan].call = call;
	spin_unlock(&conn->state_lock);

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

	rxrpc_start_call_timer(call);
	_leave("");
}

/*
 * Note the re-emergence of a call.
 */
void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
{
	if (call) {
		int r = refcount_read(&call->ref);

		trace_rxrpc_call(call->debug_id, r, 0, why);
	}
}

struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
				      enum rxrpc_call_trace why)
{
	int r;

	if (!call || !__refcount_inc_not_zero(&call->ref, &r))
		return NULL;
	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
	return call;
}

/*
 * Note the addition of a ref on a call.
 */
void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
{
	int r;

	__refcount_inc(&call->ref, &r);
	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
}

/*
 * Clean up the Rx skb ring.
 */
static void rxrpc_cleanup_ring(struct rxrpc_call *call)
{
	rxrpc_purge_queue(&call->recvmsg_queue);
	rxrpc_purge_queue(&call->rx_oos_queue);
}

/*
 * Detach a call from its owning socket.
 */
void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
{
	struct rxrpc_connection *conn = call->conn;
	bool put = false, putu = false;

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

	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
			 call->flags, rxrpc_call_see_release);

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

	rxrpc_put_call_slot(call);

	/* Make sure we don't get any more notifications */
	spin_lock(&rx->recvmsg_lock);

	if (!list_empty(&call->recvmsg_link)) {
		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
		       call, call->events, call->flags);
		list_del(&call->recvmsg_link);
		put = true;
	}

	/* list_empty() must return false in rxrpc_notify_socket() */
	call->recvmsg_link.next = NULL;
	call->recvmsg_link.prev = NULL;

	spin_unlock(&rx->recvmsg_lock);
	if (put)
		rxrpc_put_call(call, rxrpc_call_put_unnotify);

	write_lock(&rx->call_lock);

	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
		rb_erase(&call->sock_node, &rx->calls);
		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
		putu = true;
	}

	list_del(&call->sock_link);
	write_unlock(&rx->call_lock);

	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);

	if (putu)
		rxrpc_put_call(call, rxrpc_call_put_userid);

	_leave("");
}

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

	_enter("%p", rx);

	while (!list_empty(&rx->to_be_accepted)) {
		call = list_entry(rx->to_be_accepted.next,
				  struct rxrpc_call, accept_link);
		list_del(&call->accept_link);
		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
				    rxrpc_abort_call_sock_release_tba);
		rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
	}

	while (!list_empty(&rx->sock_calls)) {
		call = list_entry(rx->sock_calls.next,
				  struct rxrpc_call, sock_link);
		rxrpc_get_call(call, rxrpc_call_get_release_sock);
		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
				    rxrpc_abort_call_sock_release);
		rxrpc_release_call(rx, call);
		rxrpc_put_call(call, rxrpc_call_put_release_sock);
	}

	_leave("");
}

/*
 * release a call
 */
void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
{
	struct rxrpc_net *rxnet = call->rxnet;
	unsigned int debug_id = call->debug_id;
	bool dead;
	int r;

	ASSERT(call != NULL);

	dead = __refcount_dec_and_test(&call->ref, &r);
	trace_rxrpc_call(debug_id, r - 1, 0, why);
	if (dead) {
		ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);

		if (!list_empty(&call->link)) {
			spin_lock(&rxnet->call_lock);
			list_del_init(&call->link);
			spin_unlock(&rxnet->call_lock);
		}

		rxrpc_cleanup_call(call);
	}
}

/*
 * Free up the call under RCU.
 */
static void rxrpc_rcu_free_call(struct rcu_head *rcu)
{
	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
	struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);

	kmem_cache_free(rxrpc_call_jar, call);
	if (atomic_dec_and_test(&rxnet->nr_calls))
		wake_up_var(&rxnet->nr_calls);
}

/*
 * Final call destruction - but must be done in process context.
 */
static void rxrpc_destroy_call(struct work_struct *work)
{
	struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
	struct rxrpc_txbuf *txb;

	del_timer_sync(&call->timer);

	rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
	rxrpc_cleanup_ring(call);
	while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
					       struct rxrpc_txbuf, call_link))) {
		list_del(&txb->call_link);
		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
	}
	while ((txb = list_first_entry_or_null(&call->tx_buffer,
					       struct rxrpc_txbuf, call_link))) {
		list_del(&txb->call_link);
		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
	}

	rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
	rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
	rxrpc_deactivate_bundle(call->bundle);
	rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
	rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
	rxrpc_put_local(call->local, rxrpc_local_put_call);
	call_rcu(&call->rcu, rxrpc_rcu_free_call);
}

/*
 * clean up a call
 */
void rxrpc_cleanup_call(struct rxrpc_call *call)
{
	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));

	ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));

	del_timer(&call->timer);

	if (rcu_read_lock_held())
		/* Can't use the rxrpc workqueue as we need to cancel/flush
		 * something that may be running/waiting there.
		 */
		schedule_work(&call->destroyer);
	else
		rxrpc_destroy_call(&call->destroyer);
}

/*
 * Make sure that all calls are gone from a network namespace.  To reach this
 * point, any open UDP sockets in that namespace must have been closed, so any
 * outstanding calls cannot be doing I/O.
 */
void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
{
	struct rxrpc_call *call;

	_enter("");

	if (!list_empty(&rxnet->calls)) {
		spin_lock(&rxnet->call_lock);

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

			rxrpc_see_call(call, rxrpc_call_see_zap);
			list_del_init(&call->link);

			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
			       call, refcount_read(&call->ref),
			       rxrpc_call_states[__rxrpc_call_state(call)],
			       call->flags, call->events);

			spin_unlock(&rxnet->call_lock);
			cond_resched();
			spin_lock(&rxnet->call_lock);
		}

		spin_unlock(&rxnet->call_lock);
	}

	atomic_dec(&rxnet->nr_calls);
	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
}