1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* RxRPC individual remote procedure call handling
  3 *
  4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  5 * Written by David Howells (dhowells@redhat.com)
  6 */
  7
  8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  9
 10#include <linux/slab.h>
 11#include <linux/module.h>
 12#include <linux/circ_buf.h>
 13#include <linux/spinlock_types.h>
 14#include <net/sock.h>
 15#include <net/af_rxrpc.h>
 16#include "ar-internal.h"
 17
 18const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
 19	[RXRPC_CALL_UNINITIALISED]		= "Uninit  ",
 20	[RXRPC_CALL_CLIENT_AWAIT_CONN]		= "ClWtConn",
 21	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
 22	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
 23	[RXRPC_CALL_CLIENT_RECV_REPLY]		= "ClRcvRpl",
 24	[RXRPC_CALL_SERVER_PREALLOC]		= "SvPrealc",
 25	[RXRPC_CALL_SERVER_SECURING]		= "SvSecure",
 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};
 32
 33const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
 34	[RXRPC_CALL_SUCCEEDED]			= "Complete",
 35	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
 36	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
 37	[RXRPC_CALL_LOCAL_ERROR]		= "LocError",
 38	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
 39};
 40
 41struct kmem_cache *rxrpc_call_jar;
 42
 43static struct semaphore rxrpc_call_limiter =
 44	__SEMAPHORE_INITIALIZER(rxrpc_call_limiter, 1000);
 45static struct semaphore rxrpc_kernel_call_limiter =
 46	__SEMAPHORE_INITIALIZER(rxrpc_kernel_call_limiter, 1000);
 47
 48void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
 49{
 50	struct rxrpc_local *local = call->local;
 51	bool busy;
 52
 53	if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
 54		spin_lock_bh(&local->lock);
 55		busy = !list_empty(&call->attend_link);
 56		trace_rxrpc_poke_call(call, busy, what);
 
 
 57		if (!busy) {
 58			rxrpc_get_call(call, rxrpc_call_get_poke);
 59			list_add_tail(&call->attend_link, &local->call_attend_q);
 60		}
 61		spin_unlock_bh(&local->lock);
 62		rxrpc_wake_up_io_thread(local);
 
 63	}
 64}
 65
 66static void rxrpc_call_timer_expired(struct timer_list *t)
 67{
 68	struct rxrpc_call *call = from_timer(call, t, timer);
 69
 70	_enter("%d", call->debug_id);
 71
 72	if (!__rxrpc_call_is_complete(call)) {
 73		trace_rxrpc_timer_expired(call, jiffies);
 74		rxrpc_poke_call(call, rxrpc_call_poke_timer);
 75	}
 76}
 77
 78void rxrpc_reduce_call_timer(struct rxrpc_call *call,
 79			     unsigned long expire_at,
 80			     unsigned long now,
 81			     enum rxrpc_timer_trace why)
 82{
 83	trace_rxrpc_timer(call, why, now);
 84	timer_reduce(&call->timer, expire_at);
 85}
 86
 87static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
 88
 89static void rxrpc_destroy_call(struct work_struct *);
 90
 91/*
 92 * find an extant server call
 93 * - called in process context with IRQs enabled
 94 */
 95struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
 96					      unsigned long user_call_ID)
 97{
 98	struct rxrpc_call *call;
 99	struct rb_node *p;
100
101	_enter("%p,%lx", rx, user_call_ID);
102
103	read_lock(&rx->call_lock);
104
105	p = rx->calls.rb_node;
106	while (p) {
107		call = rb_entry(p, struct rxrpc_call, sock_node);
108
109		if (user_call_ID < call->user_call_ID)
110			p = p->rb_left;
111		else if (user_call_ID > call->user_call_ID)
112			p = p->rb_right;
113		else
114			goto found_extant_call;
115	}
116
117	read_unlock(&rx->call_lock);
118	_leave(" = NULL");
119	return NULL;
120
121found_extant_call:
122	rxrpc_get_call(call, rxrpc_call_get_sendmsg);
123	read_unlock(&rx->call_lock);
124	_leave(" = %p [%d]", call, refcount_read(&call->ref));
125	return call;
126}
127
128/*
129 * allocate a new call
130 */
131struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
132				    unsigned int debug_id)
133{
134	struct rxrpc_call *call;
135	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
136
137	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
138	if (!call)
139		return NULL;
140
141	mutex_init(&call->user_mutex);
142
143	/* Prevent lockdep reporting a deadlock false positive between the afs
144	 * filesystem and sys_sendmsg() via the mmap sem.
145	 */
146	if (rx->sk.sk_kern_sock)
147		lockdep_set_class(&call->user_mutex,
148				  &rxrpc_call_user_mutex_lock_class_key);
149
150	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
151	INIT_WORK(&call->destroyer, rxrpc_destroy_call);
152	INIT_LIST_HEAD(&call->link);
153	INIT_LIST_HEAD(&call->wait_link);
154	INIT_LIST_HEAD(&call->accept_link);
155	INIT_LIST_HEAD(&call->recvmsg_link);
156	INIT_LIST_HEAD(&call->sock_link);
157	INIT_LIST_HEAD(&call->attend_link);
158	INIT_LIST_HEAD(&call->tx_sendmsg);
159	INIT_LIST_HEAD(&call->tx_buffer);
160	skb_queue_head_init(&call->recvmsg_queue);
161	skb_queue_head_init(&call->rx_oos_queue);
162	init_waitqueue_head(&call->waitq);
163	spin_lock_init(&call->notify_lock);
164	spin_lock_init(&call->tx_lock);
165	refcount_set(&call->ref, 1);
166	call->debug_id = debug_id;
167	call->tx_total_len = -1;
168	call->next_rx_timo = 20 * HZ;
169	call->next_req_timo = 1 * HZ;
170	atomic64_set(&call->ackr_window, 0x100000001ULL);
 
171
172	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
173
174	call->rx_winsize = rxrpc_rx_window_size;
175	call->tx_winsize = 16;
176
177	if (RXRPC_TX_SMSS > 2190)
178		call->cong_cwnd = 2;
179	else if (RXRPC_TX_SMSS > 1095)
180		call->cong_cwnd = 3;
181	else
182		call->cong_cwnd = 4;
183	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
184
185	call->rxnet = rxnet;
186	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
187	atomic_inc(&rxnet->nr_calls);
188	return call;
189}
190
191/*
192 * Allocate a new client call.
193 */
194static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
195						  struct sockaddr_rxrpc *srx,
196						  struct rxrpc_conn_parameters *cp,
197						  struct rxrpc_call_params *p,
198						  gfp_t gfp,
199						  unsigned int debug_id)
200{
201	struct rxrpc_call *call;
202	ktime_t now;
203	int ret;
204
205	_enter("");
206
207	call = rxrpc_alloc_call(rx, gfp, debug_id);
208	if (!call)
209		return ERR_PTR(-ENOMEM);
210	now = ktime_get_real();
211	call->acks_latest_ts	= now;
212	call->cong_tstamp	= now;
213	call->dest_srx		= *srx;
 
214	call->interruptibility	= p->interruptibility;
215	call->tx_total_len	= p->tx_total_len;
216	call->key		= key_get(cp->key);
 
217	call->local		= rxrpc_get_local(cp->local, rxrpc_local_get_call);
218	call->security_level	= cp->security_level;
219	if (p->kernel)
220		__set_bit(RXRPC_CALL_KERNEL, &call->flags);
221	if (cp->upgrade)
222		__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
223	if (cp->exclusive)
224		__set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
225
 
 
 
 
 
 
 
226	ret = rxrpc_init_client_call_security(call);
227	if (ret < 0) {
228		rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
229		rxrpc_put_call(call, rxrpc_call_put_discard_error);
230		return ERR_PTR(ret);
231	}
232
233	rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
234
235	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
236			 p->user_call_ID, rxrpc_call_new_client);
237
238	_leave(" = %p", call);
239	return call;
240}
241
242/*
243 * Initiate the call ack/resend/expiry timer.
244 */
245void rxrpc_start_call_timer(struct rxrpc_call *call)
246{
247	unsigned long now = jiffies;
248	unsigned long j = now + MAX_JIFFY_OFFSET;
249
250	call->delay_ack_at = j;
251	call->ack_lost_at = j;
252	call->resend_at = j;
253	call->ping_at = j;
254	call->keepalive_at = j;
255	call->expect_rx_by = j;
256	call->expect_req_by = j;
257	call->expect_term_by = j;
258	call->timer.expires = now;
259}
260
261/*
262 * Wait for a call slot to become available.
263 */
264static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
265{
266	struct semaphore *limiter = &rxrpc_call_limiter;
267
268	if (p->kernel)
269		limiter = &rxrpc_kernel_call_limiter;
270	if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
271		down(limiter);
272		return limiter;
273	}
274	return down_interruptible(limiter) < 0 ? NULL : limiter;
275}
276
277/*
278 * Release a call slot.
279 */
280static void rxrpc_put_call_slot(struct rxrpc_call *call)
281{
282	struct semaphore *limiter = &rxrpc_call_limiter;
283
284	if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
285		limiter = &rxrpc_kernel_call_limiter;
286	up(limiter);
287}
288
289/*
290 * Start the process of connecting a call.  We obtain a peer and a connection
291 * bundle, but the actual association of a call with a connection is offloaded
292 * to the I/O thread to simplify locking.
293 */
294static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
295{
296	struct rxrpc_local *local = call->local;
297	int ret = -ENOMEM;
298
299	_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
300
301	call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp);
302	if (!call->peer)
303		goto error;
304
305	ret = rxrpc_look_up_bundle(call, gfp);
306	if (ret < 0)
307		goto error;
308
309	trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
310	rxrpc_get_call(call, rxrpc_call_get_io_thread);
311	spin_lock(&local->client_call_lock);
312	list_add_tail(&call->wait_link, &local->new_client_calls);
313	spin_unlock(&local->client_call_lock);
314	rxrpc_wake_up_io_thread(local);
315	return 0;
316
317error:
318	__set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
319	return ret;
320}
321
322/*
323 * Set up a call for the given parameters.
324 * - Called with the socket lock held, which it must release.
325 * - If it returns a call, the call's lock will need releasing by the caller.
326 */
327struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
328					 struct rxrpc_conn_parameters *cp,
329					 struct sockaddr_rxrpc *srx,
330					 struct rxrpc_call_params *p,
331					 gfp_t gfp,
332					 unsigned int debug_id)
333	__releases(&rx->sk.sk_lock.slock)
334	__acquires(&call->user_mutex)
335{
336	struct rxrpc_call *call, *xcall;
337	struct rxrpc_net *rxnet;
338	struct semaphore *limiter;
339	struct rb_node *parent, **pp;
340	int ret;
341
342	_enter("%p,%lx", rx, p->user_call_ID);
343
 
 
 
 
 
344	limiter = rxrpc_get_call_slot(p, gfp);
345	if (!limiter) {
346		release_sock(&rx->sk);
347		return ERR_PTR(-ERESTARTSYS);
348	}
349
350	call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id);
351	if (IS_ERR(call)) {
352		release_sock(&rx->sk);
353		up(limiter);
354		_leave(" = %ld", PTR_ERR(call));
355		return call;
356	}
357
358	/* We need to protect a partially set up call against the user as we
359	 * will be acting outside the socket lock.
360	 */
361	mutex_lock(&call->user_mutex);
362
363	/* Publish the call, even though it is incompletely set up as yet */
364	write_lock(&rx->call_lock);
365
366	pp = &rx->calls.rb_node;
367	parent = NULL;
368	while (*pp) {
369		parent = *pp;
370		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
371
372		if (p->user_call_ID < xcall->user_call_ID)
373			pp = &(*pp)->rb_left;
374		else if (p->user_call_ID > xcall->user_call_ID)
375			pp = &(*pp)->rb_right;
376		else
377			goto error_dup_user_ID;
378	}
379
380	rcu_assign_pointer(call->socket, rx);
381	call->user_call_ID = p->user_call_ID;
382	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
383	rxrpc_get_call(call, rxrpc_call_get_userid);
384	rb_link_node(&call->sock_node, parent, pp);
385	rb_insert_color(&call->sock_node, &rx->calls);
386	list_add(&call->sock_link, &rx->sock_calls);
387
388	write_unlock(&rx->call_lock);
389
390	rxnet = call->rxnet;
391	spin_lock(&rxnet->call_lock);
392	list_add_tail_rcu(&call->link, &rxnet->calls);
393	spin_unlock(&rxnet->call_lock);
394
395	/* From this point on, the call is protected by its own lock. */
396	release_sock(&rx->sk);
397
398	/* Set up or get a connection record and set the protocol parameters,
399	 * including channel number and call ID.
400	 */
401	ret = rxrpc_connect_call(call, gfp);
402	if (ret < 0)
403		goto error_attached_to_socket;
404
405	_leave(" = %p [new]", call);
406	return call;
407
408	/* We unexpectedly found the user ID in the list after taking
409	 * the call_lock.  This shouldn't happen unless the user races
410	 * with itself and tries to add the same user ID twice at the
411	 * same time in different threads.
412	 */
413error_dup_user_ID:
414	write_unlock(&rx->call_lock);
415	release_sock(&rx->sk);
416	rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
417	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
418			 rxrpc_call_see_userid_exists);
419	mutex_unlock(&call->user_mutex);
420	rxrpc_put_call(call, rxrpc_call_put_userid_exists);
421	_leave(" = -EEXIST");
422	return ERR_PTR(-EEXIST);
423
424	/* We got an error, but the call is attached to the socket and is in
425	 * need of release.  However, we might now race with recvmsg() when it
426	 * completion notifies the socket.  Return 0 from sys_sendmsg() and
427	 * leave the error to recvmsg() to deal with.
428	 */
429error_attached_to_socket:
430	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
431			 rxrpc_call_see_connect_failed);
432	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
433	_leave(" = c=%08x [err]", call->debug_id);
434	return call;
435}
436
437/*
438 * Set up an incoming call.  call->conn points to the connection.
439 * This is called in BH context and isn't allowed to fail.
440 */
441void rxrpc_incoming_call(struct rxrpc_sock *rx,
442			 struct rxrpc_call *call,
443			 struct sk_buff *skb)
444{
445	struct rxrpc_connection *conn = call->conn;
446	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
447	u32 chan;
448
449	_enter(",%d", call->conn->debug_id);
450
451	rcu_assign_pointer(call->socket, rx);
452	call->call_id		= sp->hdr.callNumber;
453	call->dest_srx.srx_service = sp->hdr.serviceId;
454	call->cid		= sp->hdr.cid;
455	call->cong_tstamp	= skb->tstamp;
456
457	__set_bit(RXRPC_CALL_EXPOSED, &call->flags);
458	rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
459
460	spin_lock(&conn->state_lock);
461
462	switch (conn->state) {
463	case RXRPC_CONN_SERVICE_UNSECURED:
464	case RXRPC_CONN_SERVICE_CHALLENGING:
465		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
466		break;
467	case RXRPC_CONN_SERVICE:
468		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
469		break;
470
471	case RXRPC_CONN_ABORTED:
472		rxrpc_set_call_completion(call, conn->completion,
473					  conn->abort_code, conn->error);
474		break;
475	default:
476		BUG();
477	}
478
479	rxrpc_get_call(call, rxrpc_call_get_io_thread);
480
481	/* Set the channel for this call.  We don't get channel_lock as we're
482	 * only defending against the data_ready handler (which we're called
483	 * from) and the RESPONSE packet parser (which is only really
484	 * interested in call_counter and can cope with a disagreement with the
485	 * call pointer).
486	 */
487	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
488	conn->channels[chan].call_counter = call->call_id;
489	conn->channels[chan].call_id = call->call_id;
490	conn->channels[chan].call = call;
491	spin_unlock(&conn->state_lock);
492
493	spin_lock(&conn->peer->lock);
494	hlist_add_head(&call->error_link, &conn->peer->error_targets);
495	spin_unlock(&conn->peer->lock);
496
497	rxrpc_start_call_timer(call);
498	_leave("");
499}
500
501/*
502 * Note the re-emergence of a call.
503 */
504void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
505{
506	if (call) {
507		int r = refcount_read(&call->ref);
508
509		trace_rxrpc_call(call->debug_id, r, 0, why);
510	}
511}
512
513struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
514				      enum rxrpc_call_trace why)
515{
516	int r;
517
518	if (!call || !__refcount_inc_not_zero(&call->ref, &r))
519		return NULL;
520	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
521	return call;
522}
523
524/*
525 * Note the addition of a ref on a call.
526 */
527void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
528{
529	int r;
530
531	__refcount_inc(&call->ref, &r);
532	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
533}
534
535/*
536 * Clean up the Rx skb ring.
537 */
538static void rxrpc_cleanup_ring(struct rxrpc_call *call)
539{
540	skb_queue_purge(&call->recvmsg_queue);
541	skb_queue_purge(&call->rx_oos_queue);
542}
543
544/*
545 * Detach a call from its owning socket.
546 */
547void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
548{
549	struct rxrpc_connection *conn = call->conn;
550	bool put = false, putu = false;
551
552	_enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
553
554	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
555			 call->flags, rxrpc_call_see_release);
556
557	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
558		BUG();
559
560	rxrpc_put_call_slot(call);
561
562	/* Make sure we don't get any more notifications */
563	write_lock(&rx->recvmsg_lock);
564
565	if (!list_empty(&call->recvmsg_link)) {
566		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
567		       call, call->events, call->flags);
568		list_del(&call->recvmsg_link);
569		put = true;
570	}
571
572	/* list_empty() must return false in rxrpc_notify_socket() */
573	call->recvmsg_link.next = NULL;
574	call->recvmsg_link.prev = NULL;
575
576	write_unlock(&rx->recvmsg_lock);
577	if (put)
578		rxrpc_put_call(call, rxrpc_call_put_unnotify);
579
580	write_lock(&rx->call_lock);
581
582	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
583		rb_erase(&call->sock_node, &rx->calls);
584		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
585		putu = true;
586	}
587
588	list_del(&call->sock_link);
589	write_unlock(&rx->call_lock);
590
591	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
592
593	if (putu)
594		rxrpc_put_call(call, rxrpc_call_put_userid);
595
596	_leave("");
597}
598
599/*
600 * release all the calls associated with a socket
601 */
602void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
603{
604	struct rxrpc_call *call;
605
606	_enter("%p", rx);
607
608	while (!list_empty(&rx->to_be_accepted)) {
609		call = list_entry(rx->to_be_accepted.next,
610				  struct rxrpc_call, accept_link);
611		list_del(&call->accept_link);
612		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
613				    rxrpc_abort_call_sock_release_tba);
614		rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
615	}
616
617	while (!list_empty(&rx->sock_calls)) {
618		call = list_entry(rx->sock_calls.next,
619				  struct rxrpc_call, sock_link);
620		rxrpc_get_call(call, rxrpc_call_get_release_sock);
621		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
622				    rxrpc_abort_call_sock_release);
623		rxrpc_release_call(rx, call);
624		rxrpc_put_call(call, rxrpc_call_put_release_sock);
625	}
626
627	_leave("");
628}
629
630/*
631 * release a call
632 */
633void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
634{
635	struct rxrpc_net *rxnet = call->rxnet;
636	unsigned int debug_id = call->debug_id;
637	bool dead;
638	int r;
639
640	ASSERT(call != NULL);
641
642	dead = __refcount_dec_and_test(&call->ref, &r);
643	trace_rxrpc_call(debug_id, r - 1, 0, why);
644	if (dead) {
645		ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
646
647		if (!list_empty(&call->link)) {
648			spin_lock(&rxnet->call_lock);
649			list_del_init(&call->link);
650			spin_unlock(&rxnet->call_lock);
651		}
652
653		rxrpc_cleanup_call(call);
654	}
655}
656
657/*
658 * Free up the call under RCU.
659 */
660static void rxrpc_rcu_free_call(struct rcu_head *rcu)
661{
662	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
663	struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
664
665	kmem_cache_free(rxrpc_call_jar, call);
666	if (atomic_dec_and_test(&rxnet->nr_calls))
667		wake_up_var(&rxnet->nr_calls);
668}
669
670/*
671 * Final call destruction - but must be done in process context.
672 */
673static void rxrpc_destroy_call(struct work_struct *work)
674{
675	struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
676	struct rxrpc_txbuf *txb;
677
678	del_timer_sync(&call->timer);
679
 
680	rxrpc_cleanup_ring(call);
681	while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
682					       struct rxrpc_txbuf, call_link))) {
683		list_del(&txb->call_link);
684		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
685	}
686	while ((txb = list_first_entry_or_null(&call->tx_buffer,
687					       struct rxrpc_txbuf, call_link))) {
688		list_del(&txb->call_link);
689		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
690	}
691
692	rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
693	rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
694	rxrpc_deactivate_bundle(call->bundle);
695	rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
696	rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
697	rxrpc_put_local(call->local, rxrpc_local_put_call);
698	call_rcu(&call->rcu, rxrpc_rcu_free_call);
699}
700
701/*
702 * clean up a call
703 */
704void rxrpc_cleanup_call(struct rxrpc_call *call)
705{
706	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
707
708	ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
709	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
710
711	del_timer(&call->timer);
712
713	if (rcu_read_lock_held())
714		/* Can't use the rxrpc workqueue as we need to cancel/flush
715		 * something that may be running/waiting there.
716		 */
717		schedule_work(&call->destroyer);
718	else
719		rxrpc_destroy_call(&call->destroyer);
720}
721
722/*
723 * Make sure that all calls are gone from a network namespace.  To reach this
724 * point, any open UDP sockets in that namespace must have been closed, so any
725 * outstanding calls cannot be doing I/O.
726 */
727void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
728{
729	struct rxrpc_call *call;
730
731	_enter("");
732
733	if (!list_empty(&rxnet->calls)) {
734		spin_lock(&rxnet->call_lock);
735
736		while (!list_empty(&rxnet->calls)) {
737			call = list_entry(rxnet->calls.next,
738					  struct rxrpc_call, link);
739			_debug("Zapping call %p", call);
740
741			rxrpc_see_call(call, rxrpc_call_see_zap);
742			list_del_init(&call->link);
743
744			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
745			       call, refcount_read(&call->ref),
746			       rxrpc_call_states[__rxrpc_call_state(call)],
747			       call->flags, call->events);
748
749			spin_unlock(&rxnet->call_lock);
750			cond_resched();
751			spin_lock(&rxnet->call_lock);
752		}
753
754		spin_unlock(&rxnet->call_lock);
755	}
756
757	atomic_dec(&rxnet->nr_calls);
758	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
759}