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v6.13.7
  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_RECV_REQUEST]	= "SvRcvReq",
 26	[RXRPC_CALL_SERVER_ACK_REQUEST]		= "SvAckReq",
 27	[RXRPC_CALL_SERVER_SEND_REPLY]		= "SvSndRpl",
 28	[RXRPC_CALL_SERVER_AWAIT_ACK]		= "SvAwtACK",
 29	[RXRPC_CALL_COMPLETE]			= "Complete",
 30};
 31
 32const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
 33	[RXRPC_CALL_SUCCEEDED]			= "Complete",
 34	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
 35	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
 36	[RXRPC_CALL_LOCAL_ERROR]		= "LocError",
 37	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
 38};
 39
 40struct kmem_cache *rxrpc_call_jar;
 41
 42static DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000);
 43static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000);
 44
 45void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
 46{
 47	struct rxrpc_local *local = call->local;
 48	bool busy;
 49
 50	if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
 51		spin_lock_bh(&local->lock);
 52		busy = !list_empty(&call->attend_link);
 53		trace_rxrpc_poke_call(call, busy, what);
 54		if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
 55			busy = true;
 56		if (!busy) {
 57			list_add_tail(&call->attend_link, &local->call_attend_q);
 58		}
 59		spin_unlock_bh(&local->lock);
 60		if (!busy)
 61			rxrpc_wake_up_io_thread(local);
 62	}
 63}
 64
 65static void rxrpc_call_timer_expired(struct timer_list *t)
 66{
 67	struct rxrpc_call *call = from_timer(call, t, timer);
 68
 69	_enter("%d", call->debug_id);
 70
 71	if (!__rxrpc_call_is_complete(call)) {
 72		trace_rxrpc_timer_expired(call);
 73		rxrpc_poke_call(call, rxrpc_call_poke_timer);
 74	}
 75}
 76
 77static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
 78
 79static void rxrpc_destroy_call(struct work_struct *);
 80
 81/*
 82 * find an extant server call
 83 * - called in process context with IRQs enabled
 84 */
 85struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
 86					      unsigned long user_call_ID)
 87{
 88	struct rxrpc_call *call;
 89	struct rb_node *p;
 90
 91	_enter("%p,%lx", rx, user_call_ID);
 92
 93	read_lock(&rx->call_lock);
 94
 95	p = rx->calls.rb_node;
 96	while (p) {
 97		call = rb_entry(p, struct rxrpc_call, sock_node);
 98
 99		if (user_call_ID < call->user_call_ID)
100			p = p->rb_left;
101		else if (user_call_ID > call->user_call_ID)
102			p = p->rb_right;
103		else
104			goto found_extant_call;
105	}
106
107	read_unlock(&rx->call_lock);
108	_leave(" = NULL");
109	return NULL;
110
111found_extant_call:
112	rxrpc_get_call(call, rxrpc_call_get_sendmsg);
113	read_unlock(&rx->call_lock);
114	_leave(" = %p [%d]", call, refcount_read(&call->ref));
115	return call;
116}
117
118/*
119 * allocate a new call
120 */
121struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
122				    unsigned int debug_id)
123{
124	struct rxrpc_call *call;
125	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
126
127	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
128	if (!call)
129		return NULL;
130
 
 
 
 
 
 
 
 
 
 
131	mutex_init(&call->user_mutex);
132
133	/* Prevent lockdep reporting a deadlock false positive between the afs
134	 * filesystem and sys_sendmsg() via the mmap sem.
135	 */
136	if (rx->sk.sk_kern_sock)
137		lockdep_set_class(&call->user_mutex,
138				  &rxrpc_call_user_mutex_lock_class_key);
139
140	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
141	INIT_WORK(&call->destroyer, rxrpc_destroy_call);
142	INIT_LIST_HEAD(&call->link);
143	INIT_LIST_HEAD(&call->wait_link);
144	INIT_LIST_HEAD(&call->accept_link);
145	INIT_LIST_HEAD(&call->recvmsg_link);
146	INIT_LIST_HEAD(&call->sock_link);
147	INIT_LIST_HEAD(&call->attend_link);
148	INIT_LIST_HEAD(&call->tx_sendmsg);
149	INIT_LIST_HEAD(&call->tx_buffer);
150	skb_queue_head_init(&call->recvmsg_queue);
151	skb_queue_head_init(&call->rx_oos_queue);
152	init_waitqueue_head(&call->waitq);
 
153	spin_lock_init(&call->notify_lock);
154	spin_lock_init(&call->tx_lock);
155	refcount_set(&call->ref, 1);
156	call->debug_id		= debug_id;
157	call->tx_total_len	= -1;
158	call->next_rx_timo	= 20 * HZ;
159	call->next_req_timo	= 1 * HZ;
160	call->ackr_window	= 1;
161	call->ackr_wtop		= 1;
162	call->delay_ack_at	= KTIME_MAX;
163	call->ack_lost_at	= KTIME_MAX;
164	call->resend_at		= KTIME_MAX;
165	call->ping_at		= KTIME_MAX;
166	call->keepalive_at	= KTIME_MAX;
167	call->expect_rx_by	= KTIME_MAX;
168	call->expect_req_by	= KTIME_MAX;
169	call->expect_term_by	= KTIME_MAX;
170
171	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
172
 
173	call->rx_winsize = rxrpc_rx_window_size;
174	call->tx_winsize = 16;
 
175
176	call->cong_cwnd = RXRPC_MIN_CWND;
177	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
178
179	call->rxnet = rxnet;
180	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
181	atomic_inc(&rxnet->nr_calls);
182	return call;
 
 
 
 
 
 
183}
184
185/*
186 * Allocate a new client call.
187 */
188static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
189						  struct rxrpc_conn_parameters *cp,
190						  struct rxrpc_call_params *p,
191						  gfp_t gfp,
192						  unsigned int debug_id)
193{
194	struct rxrpc_call *call;
195	ktime_t now;
196	int ret;
197
198	_enter("");
199
200	call = rxrpc_alloc_call(rx, gfp, debug_id);
201	if (!call)
202		return ERR_PTR(-ENOMEM);
 
 
 
203	now = ktime_get_real();
204	call->acks_latest_ts	= now;
205	call->cong_tstamp	= now;
206	call->dest_srx		= cp->peer->srx;
207	call->dest_srx.srx_service = cp->service_id;
208	call->interruptibility	= p->interruptibility;
209	call->tx_total_len	= p->tx_total_len;
210	call->key		= key_get(cp->key);
211	call->peer		= rxrpc_get_peer(cp->peer, rxrpc_peer_get_call);
212	call->local		= rxrpc_get_local(cp->local, rxrpc_local_get_call);
213	call->security_level	= cp->security_level;
214	if (p->kernel)
215		__set_bit(RXRPC_CALL_KERNEL, &call->flags);
216	if (cp->upgrade)
217		__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
218	if (cp->exclusive)
219		__set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
220
221	if (p->timeouts.normal)
222		call->next_rx_timo = min(p->timeouts.normal, 1);
223	if (p->timeouts.idle)
224		call->next_req_timo = min(p->timeouts.idle, 1);
225	if (p->timeouts.hard)
226		call->hard_timo = p->timeouts.hard;
227
228	ret = rxrpc_init_client_call_security(call);
229	if (ret < 0) {
230		rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
231		rxrpc_put_call(call, rxrpc_call_put_discard_error);
232		return ERR_PTR(ret);
233	}
234
235	rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
236
237	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
238			 p->user_call_ID, rxrpc_call_new_client);
239
240	_leave(" = %p", call);
241	return call;
242}
243
244/*
245 * Initiate the call ack/resend/expiry timer.
246 */
247void rxrpc_start_call_timer(struct rxrpc_call *call)
248{
249	if (call->hard_timo) {
250		ktime_t delay = ms_to_ktime(call->hard_timo * 1000);
251
252		call->expect_term_by = ktime_add(ktime_get_real(), delay);
253		trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
254	}
255	call->timer.expires = jiffies;
256}
257
258/*
259 * Wait for a call slot to become available.
260 */
261static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
262{
263	struct semaphore *limiter = &rxrpc_call_limiter;
264
265	if (p->kernel)
266		limiter = &rxrpc_kernel_call_limiter;
267	if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
268		down(limiter);
269		return limiter;
270	}
271	return down_interruptible(limiter) < 0 ? NULL : limiter;
272}
273
274/*
275 * Release a call slot.
276 */
277static void rxrpc_put_call_slot(struct rxrpc_call *call)
278{
279	struct semaphore *limiter = &rxrpc_call_limiter;
280
281	if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
282		limiter = &rxrpc_kernel_call_limiter;
283	up(limiter);
284}
285
286/*
287 * Start the process of connecting a call.  We obtain a peer and a connection
288 * bundle, but the actual association of a call with a connection is offloaded
289 * to the I/O thread to simplify locking.
290 */
291static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
292{
293	struct rxrpc_local *local = call->local;
294	int ret = -ENOMEM;
295
296	_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
297
298	ret = rxrpc_look_up_bundle(call, gfp);
299	if (ret < 0)
300		goto error;
301
302	trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
303	rxrpc_get_call(call, rxrpc_call_get_io_thread);
304	spin_lock(&local->client_call_lock);
305	list_add_tail(&call->wait_link, &local->new_client_calls);
306	spin_unlock(&local->client_call_lock);
307	rxrpc_wake_up_io_thread(local);
308	return 0;
309
310error:
311	__set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
312	return ret;
313}
314
315/*
316 * Set up a call for the given parameters.
317 * - Called with the socket lock held, which it must release.
318 * - If it returns a call, the call's lock will need releasing by the caller.
319 */
320struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
321					 struct rxrpc_conn_parameters *cp,
 
322					 struct rxrpc_call_params *p,
323					 gfp_t gfp,
324					 unsigned int debug_id)
325	__releases(&rx->sk.sk_lock.slock)
326	__acquires(&call->user_mutex)
327{
328	struct rxrpc_call *call, *xcall;
329	struct rxrpc_net *rxnet;
330	struct semaphore *limiter;
331	struct rb_node *parent, **pp;
 
332	int ret;
333
334	_enter("%p,%lx", rx, p->user_call_ID);
335
336	if (WARN_ON_ONCE(!cp->peer)) {
337		release_sock(&rx->sk);
338		return ERR_PTR(-EIO);
339	}
340
341	limiter = rxrpc_get_call_slot(p, gfp);
342	if (!limiter) {
343		release_sock(&rx->sk);
344		return ERR_PTR(-ERESTARTSYS);
345	}
346
347	call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id);
348	if (IS_ERR(call)) {
349		release_sock(&rx->sk);
350		up(limiter);
351		_leave(" = %ld", PTR_ERR(call));
352		return call;
353	}
354
 
 
 
 
355	/* We need to protect a partially set up call against the user as we
356	 * will be acting outside the socket lock.
357	 */
358	mutex_lock(&call->user_mutex);
359
360	/* Publish the call, even though it is incompletely set up as yet */
361	write_lock(&rx->call_lock);
362
363	pp = &rx->calls.rb_node;
364	parent = NULL;
365	while (*pp) {
366		parent = *pp;
367		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
368
369		if (p->user_call_ID < xcall->user_call_ID)
370			pp = &(*pp)->rb_left;
371		else if (p->user_call_ID > xcall->user_call_ID)
372			pp = &(*pp)->rb_right;
373		else
374			goto error_dup_user_ID;
375	}
376
377	rcu_assign_pointer(call->socket, rx);
378	call->user_call_ID = p->user_call_ID;
379	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
380	rxrpc_get_call(call, rxrpc_call_get_userid);
381	rb_link_node(&call->sock_node, parent, pp);
382	rb_insert_color(&call->sock_node, &rx->calls);
383	list_add(&call->sock_link, &rx->sock_calls);
384
385	write_unlock(&rx->call_lock);
386
387	rxnet = call->rxnet;
388	spin_lock(&rxnet->call_lock);
389	list_add_tail_rcu(&call->link, &rxnet->calls);
390	spin_unlock(&rxnet->call_lock);
391
392	/* From this point on, the call is protected by its own lock. */
393	release_sock(&rx->sk);
394
395	/* Set up or get a connection record and set the protocol parameters,
396	 * including channel number and call ID.
397	 */
398	ret = rxrpc_connect_call(call, gfp);
399	if (ret < 0)
400		goto error_attached_to_socket;
 
 
 
 
 
 
 
401
402	_leave(" = %p [new]", call);
403	return call;
404
405	/* We unexpectedly found the user ID in the list after taking
406	 * the call_lock.  This shouldn't happen unless the user races
407	 * with itself and tries to add the same user ID twice at the
408	 * same time in different threads.
409	 */
410error_dup_user_ID:
411	write_unlock(&rx->call_lock);
412	release_sock(&rx->sk);
413	rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
414	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
415			 rxrpc_call_see_userid_exists);
 
 
 
 
 
416	mutex_unlock(&call->user_mutex);
417	rxrpc_put_call(call, rxrpc_call_put_userid_exists);
418	_leave(" = -EEXIST");
419	return ERR_PTR(-EEXIST);
420
421	/* We got an error, but the call is attached to the socket and is in
422	 * need of release.  However, we might now race with recvmsg() when it
423	 * completion notifies the socket.  Return 0 from sys_sendmsg() and
424	 * leave the error to recvmsg() to deal with.
 
 
 
 
 
 
 
 
 
 
 
 
425	 */
426error_attached_to_socket:
427	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
428			 rxrpc_call_see_connect_failed);
429	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
430	_leave(" = c=%08x [err]", call->debug_id);
431	return call;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
432}
433
434/*
435 * Set up an incoming call.  call->conn points to the connection.
436 * This is called in BH context and isn't allowed to fail.
437 */
438void rxrpc_incoming_call(struct rxrpc_sock *rx,
439			 struct rxrpc_call *call,
440			 struct sk_buff *skb)
441{
442	struct rxrpc_connection *conn = call->conn;
443	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
444	u32 chan;
445
446	_enter(",%d", call->conn->debug_id);
447
448	rcu_assign_pointer(call->socket, rx);
449	call->call_id		= sp->hdr.callNumber;
450	call->dest_srx.srx_service = sp->hdr.serviceId;
451	call->cid		= sp->hdr.cid;
 
 
 
452	call->cong_tstamp	= skb->tstamp;
453
454	__set_bit(RXRPC_CALL_EXPOSED, &call->flags);
455	rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
456
457	spin_lock(&conn->state_lock);
458
459	switch (conn->state) {
460	case RXRPC_CONN_SERVICE_UNSECURED:
461	case RXRPC_CONN_SERVICE_CHALLENGING:
462		__set_bit(RXRPC_CALL_CONN_CHALLENGING, &call->flags);
463		break;
464	case RXRPC_CONN_SERVICE:
465		break;
466
467	case RXRPC_CONN_ABORTED:
468		rxrpc_set_call_completion(call, conn->completion,
469					  conn->abort_code, conn->error);
470		break;
471	default:
472		BUG();
473	}
474
475	rxrpc_get_call(call, rxrpc_call_get_io_thread);
476
477	/* Set the channel for this call.  We don't get channel_lock as we're
478	 * only defending against the data_ready handler (which we're called
479	 * from) and the RESPONSE packet parser (which is only really
480	 * interested in call_counter and can cope with a disagreement with the
481	 * call pointer).
482	 */
483	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
484	conn->channels[chan].call_counter = call->call_id;
485	conn->channels[chan].call_id = call->call_id;
486	conn->channels[chan].call = call;
487	spin_unlock(&conn->state_lock);
 
 
 
488
489	spin_lock(&conn->peer->lock);
490	hlist_add_head(&call->error_link, &conn->peer->error_targets);
491	spin_unlock(&conn->peer->lock);
492
493	rxrpc_start_call_timer(call);
494	_leave("");
495}
496
497/*
498 * Note the re-emergence of a call.
499 */
500void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
501{
502	if (call) {
503		int r = refcount_read(&call->ref);
504
505		trace_rxrpc_call(call->debug_id, r, 0, why);
506	}
 
 
 
 
507}
508
509struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
510				      enum rxrpc_call_trace why)
 
 
511{
512	int r;
513
514	if (!call || !__refcount_inc_not_zero(&call->ref, &r))
515		return NULL;
516	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
517	return call;
 
 
518}
519
520/*
521 * Note the addition of a ref on a call.
522 */
523void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
524{
525	int r;
 
 
526
527	__refcount_inc(&call->ref, &r);
528	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
529}
530
531/*
532 * Clean up the Rx skb ring.
533 */
534static void rxrpc_cleanup_ring(struct rxrpc_call *call)
535{
536	rxrpc_purge_queue(&call->recvmsg_queue);
537	rxrpc_purge_queue(&call->rx_oos_queue);
 
 
538}
539
540/*
541 * Detach a call from its owning socket.
542 */
543void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
544{
 
545	struct rxrpc_connection *conn = call->conn;
546	bool put = false, putu = false;
 
 
 
547
548	_enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
 
549
550	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
551			 call->flags, rxrpc_call_see_release);
552
 
553	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
554		BUG();
 
555
556	rxrpc_put_call_slot(call);
557
558	/* Make sure we don't get any more notifications */
559	spin_lock(&rx->recvmsg_lock);
560
561	if (!list_empty(&call->recvmsg_link)) {
562		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
563		       call, call->events, call->flags);
564		list_del(&call->recvmsg_link);
565		put = true;
566	}
567
568	/* list_empty() must return false in rxrpc_notify_socket() */
569	call->recvmsg_link.next = NULL;
570	call->recvmsg_link.prev = NULL;
571
572	spin_unlock(&rx->recvmsg_lock);
573	if (put)
574		rxrpc_put_call(call, rxrpc_call_put_unnotify);
575
576	write_lock(&rx->call_lock);
577
578	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
579		rb_erase(&call->sock_node, &rx->calls);
580		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
581		putu = true;
582	}
583
584	list_del(&call->sock_link);
585	write_unlock(&rx->call_lock);
586
587	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
588
589	if (putu)
590		rxrpc_put_call(call, rxrpc_call_put_userid);
 
 
 
 
 
 
 
591
592	_leave("");
593}
594
595/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
596 * release all the calls associated with a socket
597 */
598void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
599{
600	struct rxrpc_call *call;
601
602	_enter("%p", rx);
603
604	while (!list_empty(&rx->to_be_accepted)) {
605		call = list_entry(rx->to_be_accepted.next,
606				  struct rxrpc_call, accept_link);
607		list_del(&call->accept_link);
608		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
609				    rxrpc_abort_call_sock_release_tba);
610		rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
611	}
612
613	while (!list_empty(&rx->sock_calls)) {
614		call = list_entry(rx->sock_calls.next,
615				  struct rxrpc_call, sock_link);
616		rxrpc_get_call(call, rxrpc_call_get_release_sock);
617		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
618				    rxrpc_abort_call_sock_release);
619		rxrpc_release_call(rx, call);
620		rxrpc_put_call(call, rxrpc_call_put_release_sock);
621	}
622
623	_leave("");
624}
625
626/*
627 * release a call
628 */
629void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
630{
631	struct rxrpc_net *rxnet = call->rxnet;
632	unsigned int debug_id = call->debug_id;
633	bool dead;
634	int r;
635
636	ASSERT(call != NULL);
637
638	dead = __refcount_dec_and_test(&call->ref, &r);
639	trace_rxrpc_call(debug_id, r - 1, 0, why);
640	if (dead) {
641		ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 
 
642
643		if (!list_empty(&call->link)) {
644			spin_lock(&rxnet->call_lock);
645			list_del_init(&call->link);
646			spin_unlock(&rxnet->call_lock);
647		}
648
649		rxrpc_cleanup_call(call);
650	}
651}
652
653/*
654 * Free up the call under RCU.
655 */
656static void rxrpc_rcu_free_call(struct rcu_head *rcu)
657{
658	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
659	struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
660
 
 
 
661	kmem_cache_free(rxrpc_call_jar, call);
662	if (atomic_dec_and_test(&rxnet->nr_calls))
663		wake_up_var(&rxnet->nr_calls);
664}
665
666/*
667 * Final call destruction - but must be done in process context.
668 */
669static void rxrpc_destroy_call(struct work_struct *work)
670{
671	struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
672	struct rxrpc_txbuf *txb;
673
674	del_timer_sync(&call->timer);
675
676	rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
677	rxrpc_cleanup_ring(call);
678	while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
679					       struct rxrpc_txbuf, call_link))) {
680		list_del(&txb->call_link);
681		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
682	}
683	while ((txb = list_first_entry_or_null(&call->tx_buffer,
684					       struct rxrpc_txbuf, call_link))) {
685		list_del(&txb->call_link);
686		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
687	}
688
689	rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
690	rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
691	rxrpc_deactivate_bundle(call->bundle);
692	rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
693	rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
694	rxrpc_put_local(call->local, rxrpc_local_put_call);
695	call_rcu(&call->rcu, rxrpc_rcu_free_call);
696}
697
698/*
699 * clean up a call
700 */
701void rxrpc_cleanup_call(struct rxrpc_call *call)
702{
 
 
 
 
703	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
704
705	ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 
 
706	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 
707
708	del_timer(&call->timer);
 
 
 
 
709
710	if (rcu_read_lock_held())
711		/* Can't use the rxrpc workqueue as we need to cancel/flush
712		 * something that may be running/waiting there.
713		 */
714		schedule_work(&call->destroyer);
715	else
716		rxrpc_destroy_call(&call->destroyer);
717}
718
719/*
720 * Make sure that all calls are gone from a network namespace.  To reach this
721 * point, any open UDP sockets in that namespace must have been closed, so any
722 * outstanding calls cannot be doing I/O.
723 */
724void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
725{
726	struct rxrpc_call *call;
727
728	_enter("");
729
730	if (!list_empty(&rxnet->calls)) {
731		spin_lock(&rxnet->call_lock);
732
733		while (!list_empty(&rxnet->calls)) {
734			call = list_entry(rxnet->calls.next,
735					  struct rxrpc_call, link);
736			_debug("Zapping call %p", call);
737
738			rxrpc_see_call(call, rxrpc_call_see_zap);
739			list_del_init(&call->link);
 
740
741			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
742			       call, refcount_read(&call->ref),
743			       rxrpc_call_states[__rxrpc_call_state(call)],
744			       call->flags, call->events);
745
746			spin_unlock(&rxnet->call_lock);
747			cond_resched();
748			spin_lock(&rxnet->call_lock);
749		}
750
751		spin_unlock(&rxnet->call_lock);
 
 
 
 
 
 
 
752	}
 
 
753
754	atomic_dec(&rxnet->nr_calls);
755	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
756}
v4.17
 
  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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 13
 14#include <linux/slab.h>
 15#include <linux/module.h>
 16#include <linux/circ_buf.h>
 17#include <linux/spinlock_types.h>
 18#include <net/sock.h>
 19#include <net/af_rxrpc.h>
 20#include "ar-internal.h"
 21
 22const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
 23	[RXRPC_CALL_UNINITIALISED]		= "Uninit  ",
 24	[RXRPC_CALL_CLIENT_AWAIT_CONN]		= "ClWtConn",
 25	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
 26	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
 27	[RXRPC_CALL_CLIENT_RECV_REPLY]		= "ClRcvRpl",
 28	[RXRPC_CALL_SERVER_PREALLOC]		= "SvPrealc",
 29	[RXRPC_CALL_SERVER_SECURING]		= "SvSecure",
 30	[RXRPC_CALL_SERVER_ACCEPTING]		= "SvAccept",
 31	[RXRPC_CALL_SERVER_RECV_REQUEST]	= "SvRcvReq",
 32	[RXRPC_CALL_SERVER_ACK_REQUEST]		= "SvAckReq",
 33	[RXRPC_CALL_SERVER_SEND_REPLY]		= "SvSndRpl",
 34	[RXRPC_CALL_SERVER_AWAIT_ACK]		= "SvAwtACK",
 35	[RXRPC_CALL_COMPLETE]			= "Complete",
 36};
 37
 38const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
 39	[RXRPC_CALL_SUCCEEDED]			= "Complete",
 40	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
 41	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
 42	[RXRPC_CALL_LOCAL_ERROR]		= "LocError",
 43	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
 44};
 45
 46struct kmem_cache *rxrpc_call_jar;
 47
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 48static void rxrpc_call_timer_expired(struct timer_list *t)
 49{
 50	struct rxrpc_call *call = from_timer(call, t, timer);
 51
 52	_enter("%d", call->debug_id);
 53
 54	if (call->state < RXRPC_CALL_COMPLETE) {
 55		trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
 56		rxrpc_queue_call(call);
 57	}
 58}
 59
 60static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
 61
 
 
 62/*
 63 * find an extant server call
 64 * - called in process context with IRQs enabled
 65 */
 66struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
 67					      unsigned long user_call_ID)
 68{
 69	struct rxrpc_call *call;
 70	struct rb_node *p;
 71
 72	_enter("%p,%lx", rx, user_call_ID);
 73
 74	read_lock(&rx->call_lock);
 75
 76	p = rx->calls.rb_node;
 77	while (p) {
 78		call = rb_entry(p, struct rxrpc_call, sock_node);
 79
 80		if (user_call_ID < call->user_call_ID)
 81			p = p->rb_left;
 82		else if (user_call_ID > call->user_call_ID)
 83			p = p->rb_right;
 84		else
 85			goto found_extant_call;
 86	}
 87
 88	read_unlock(&rx->call_lock);
 89	_leave(" = NULL");
 90	return NULL;
 91
 92found_extant_call:
 93	rxrpc_get_call(call, rxrpc_call_got);
 94	read_unlock(&rx->call_lock);
 95	_leave(" = %p [%d]", call, atomic_read(&call->usage));
 96	return call;
 97}
 98
 99/*
100 * allocate a new call
101 */
102struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
103				    unsigned int debug_id)
104{
105	struct rxrpc_call *call;
106	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
107
108	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
109	if (!call)
110		return NULL;
111
112	call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
113				    sizeof(struct sk_buff *),
114				    gfp);
115	if (!call->rxtx_buffer)
116		goto nomem;
117
118	call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
119	if (!call->rxtx_annotations)
120		goto nomem_2;
121
122	mutex_init(&call->user_mutex);
123
124	/* Prevent lockdep reporting a deadlock false positive between the afs
125	 * filesystem and sys_sendmsg() via the mmap sem.
126	 */
127	if (rx->sk.sk_kern_sock)
128		lockdep_set_class(&call->user_mutex,
129				  &rxrpc_call_user_mutex_lock_class_key);
130
131	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
132	INIT_WORK(&call->processor, &rxrpc_process_call);
133	INIT_LIST_HEAD(&call->link);
134	INIT_LIST_HEAD(&call->chan_wait_link);
135	INIT_LIST_HEAD(&call->accept_link);
136	INIT_LIST_HEAD(&call->recvmsg_link);
137	INIT_LIST_HEAD(&call->sock_link);
 
 
 
 
 
138	init_waitqueue_head(&call->waitq);
139	spin_lock_init(&call->lock);
140	spin_lock_init(&call->notify_lock);
141	rwlock_init(&call->state_lock);
142	atomic_set(&call->usage, 1);
143	call->debug_id = debug_id;
144	call->tx_total_len = -1;
145	call->next_rx_timo = 20 * HZ;
146	call->next_req_timo = 1 * HZ;
 
 
 
 
 
 
 
 
 
 
147
148	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
149
150	/* Leave space in the ring to handle a maxed-out jumbo packet */
151	call->rx_winsize = rxrpc_rx_window_size;
152	call->tx_winsize = 16;
153	call->rx_expect_next = 1;
154
155	call->cong_cwnd = 2;
156	call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
157
158	call->rxnet = rxnet;
 
159	atomic_inc(&rxnet->nr_calls);
160	return call;
161
162nomem_2:
163	kfree(call->rxtx_buffer);
164nomem:
165	kmem_cache_free(rxrpc_call_jar, call);
166	return NULL;
167}
168
169/*
170 * Allocate a new client call.
171 */
172static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
173						  struct sockaddr_rxrpc *srx,
 
174						  gfp_t gfp,
175						  unsigned int debug_id)
176{
177	struct rxrpc_call *call;
178	ktime_t now;
 
179
180	_enter("");
181
182	call = rxrpc_alloc_call(rx, gfp, debug_id);
183	if (!call)
184		return ERR_PTR(-ENOMEM);
185	call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
186	call->service_id = srx->srx_service;
187	call->tx_phase = true;
188	now = ktime_get_real();
189	call->acks_latest_ts = now;
190	call->cong_tstamp = now;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
191
192	_leave(" = %p", call);
193	return call;
194}
195
196/*
197 * Initiate the call ack/resend/expiry timer.
198 */
199static void rxrpc_start_call_timer(struct rxrpc_call *call)
200{
201	unsigned long now = jiffies;
202	unsigned long j = now + MAX_JIFFY_OFFSET;
203
204	call->ack_at = j;
205	call->ack_lost_at = j;
206	call->resend_at = j;
207	call->ping_at = j;
208	call->expect_rx_by = j;
209	call->expect_req_by = j;
210	call->expect_term_by = j;
211	call->timer.expires = now;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
212}
213
214/*
215 * Set up a call for the given parameters.
216 * - Called with the socket lock held, which it must release.
217 * - If it returns a call, the call's lock will need releasing by the caller.
218 */
219struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
220					 struct rxrpc_conn_parameters *cp,
221					 struct sockaddr_rxrpc *srx,
222					 struct rxrpc_call_params *p,
223					 gfp_t gfp,
224					 unsigned int debug_id)
225	__releases(&rx->sk.sk_lock.slock)
226	__acquires(&call->user_mutex)
227{
228	struct rxrpc_call *call, *xcall;
229	struct rxrpc_net *rxnet;
 
230	struct rb_node *parent, **pp;
231	const void *here = __builtin_return_address(0);
232	int ret;
233
234	_enter("%p,%lx", rx, p->user_call_ID);
235
236	call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
 
 
 
 
 
 
 
 
 
 
 
237	if (IS_ERR(call)) {
238		release_sock(&rx->sk);
 
239		_leave(" = %ld", PTR_ERR(call));
240		return call;
241	}
242
243	call->tx_total_len = p->tx_total_len;
244	trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
245			 here, (const void *)p->user_call_ID);
246
247	/* We need to protect a partially set up call against the user as we
248	 * will be acting outside the socket lock.
249	 */
250	mutex_lock(&call->user_mutex);
251
252	/* Publish the call, even though it is incompletely set up as yet */
253	write_lock(&rx->call_lock);
254
255	pp = &rx->calls.rb_node;
256	parent = NULL;
257	while (*pp) {
258		parent = *pp;
259		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
260
261		if (p->user_call_ID < xcall->user_call_ID)
262			pp = &(*pp)->rb_left;
263		else if (p->user_call_ID > xcall->user_call_ID)
264			pp = &(*pp)->rb_right;
265		else
266			goto error_dup_user_ID;
267	}
268
269	rcu_assign_pointer(call->socket, rx);
270	call->user_call_ID = p->user_call_ID;
271	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
272	rxrpc_get_call(call, rxrpc_call_got_userid);
273	rb_link_node(&call->sock_node, parent, pp);
274	rb_insert_color(&call->sock_node, &rx->calls);
275	list_add(&call->sock_link, &rx->sock_calls);
276
277	write_unlock(&rx->call_lock);
278
279	rxnet = call->rxnet;
280	write_lock(&rxnet->call_lock);
281	list_add_tail(&call->link, &rxnet->calls);
282	write_unlock(&rxnet->call_lock);
283
284	/* From this point on, the call is protected by its own lock. */
285	release_sock(&rx->sk);
286
287	/* Set up or get a connection record and set the protocol parameters,
288	 * including channel number and call ID.
289	 */
290	ret = rxrpc_connect_call(call, cp, srx, gfp);
291	if (ret < 0)
292		goto error;
293
294	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
295			 here, NULL);
296
297	rxrpc_start_call_timer(call);
298
299	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
300
301	_leave(" = %p [new]", call);
302	return call;
303
304	/* We unexpectedly found the user ID in the list after taking
305	 * the call_lock.  This shouldn't happen unless the user races
306	 * with itself and tries to add the same user ID twice at the
307	 * same time in different threads.
308	 */
309error_dup_user_ID:
310	write_unlock(&rx->call_lock);
311	release_sock(&rx->sk);
312	ret = -EEXIST;
313
314error:
315	__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
316				    RX_CALL_DEAD, ret);
317	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
318			 here, ERR_PTR(ret));
319	rxrpc_release_call(rx, call);
320	mutex_unlock(&call->user_mutex);
321	rxrpc_put_call(call, rxrpc_call_put);
322	_leave(" = %d", ret);
323	return ERR_PTR(ret);
324}
325
326/*
327 * Retry a call to a new address.  It is expected that the Tx queue of the call
328 * will contain data previously packaged for an old call.
329 */
330int rxrpc_retry_client_call(struct rxrpc_sock *rx,
331			    struct rxrpc_call *call,
332			    struct rxrpc_conn_parameters *cp,
333			    struct sockaddr_rxrpc *srx,
334			    gfp_t gfp)
335{
336	const void *here = __builtin_return_address(0);
337	int ret;
338
339	/* Set up or get a connection record and set the protocol parameters,
340	 * including channel number and call ID.
341	 */
342	ret = rxrpc_connect_call(call, cp, srx, gfp);
343	if (ret < 0)
344		goto error;
345
346	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
347			 here, NULL);
348
349	rxrpc_start_call_timer(call);
350
351	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
352
353	if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
354		rxrpc_queue_call(call);
355
356	_leave(" = 0");
357	return 0;
358
359error:
360	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
361				  RX_CALL_DEAD, ret);
362	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
363			 here, ERR_PTR(ret));
364	_leave(" = %d", ret);
365	return ret;
366}
367
368/*
369 * Set up an incoming call.  call->conn points to the connection.
370 * This is called in BH context and isn't allowed to fail.
371 */
372void rxrpc_incoming_call(struct rxrpc_sock *rx,
373			 struct rxrpc_call *call,
374			 struct sk_buff *skb)
375{
376	struct rxrpc_connection *conn = call->conn;
377	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
378	u32 chan;
379
380	_enter(",%d", call->conn->debug_id);
381
382	rcu_assign_pointer(call->socket, rx);
383	call->call_id		= sp->hdr.callNumber;
384	call->service_id	= sp->hdr.serviceId;
385	call->cid		= sp->hdr.cid;
386	call->state		= RXRPC_CALL_SERVER_ACCEPTING;
387	if (sp->hdr.securityIndex > 0)
388		call->state	= RXRPC_CALL_SERVER_SECURING;
389	call->cong_tstamp	= skb->tstamp;
390
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
391	/* Set the channel for this call.  We don't get channel_lock as we're
392	 * only defending against the data_ready handler (which we're called
393	 * from) and the RESPONSE packet parser (which is only really
394	 * interested in call_counter and can cope with a disagreement with the
395	 * call pointer).
396	 */
397	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
398	conn->channels[chan].call_counter = call->call_id;
399	conn->channels[chan].call_id = call->call_id;
400	rcu_assign_pointer(conn->channels[chan].call, call);
401
402	spin_lock(&conn->params.peer->lock);
403	hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
404	spin_unlock(&conn->params.peer->lock);
405
406	_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 
 
407
408	rxrpc_start_call_timer(call);
409	_leave("");
410}
411
412/*
413 * Queue a call's work processor, getting a ref to pass to the work queue.
414 */
415bool rxrpc_queue_call(struct rxrpc_call *call)
416{
417	const void *here = __builtin_return_address(0);
418	int n = __atomic_add_unless(&call->usage, 1, 0);
419	if (n == 0)
420		return false;
421	if (rxrpc_queue_work(&call->processor))
422		trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
423	else
424		rxrpc_put_call(call, rxrpc_call_put_noqueue);
425	return true;
426}
427
428/*
429 * Queue a call's work processor, passing the callers ref to the work queue.
430 */
431bool __rxrpc_queue_call(struct rxrpc_call *call)
432{
433	const void *here = __builtin_return_address(0);
434	int n = atomic_read(&call->usage);
435	ASSERTCMP(n, >=, 1);
436	if (rxrpc_queue_work(&call->processor))
437		trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
438	else
439		rxrpc_put_call(call, rxrpc_call_put_noqueue);
440	return true;
441}
442
443/*
444 * Note the re-emergence of a call.
445 */
446void rxrpc_see_call(struct rxrpc_call *call)
447{
448	const void *here = __builtin_return_address(0);
449	if (call) {
450		int n = atomic_read(&call->usage);
451
452		trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
453	}
454}
455
456/*
457 * Note the addition of a ref on a call.
458 */
459void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
460{
461	const void *here = __builtin_return_address(0);
462	int n = atomic_inc_return(&call->usage);
463
464	trace_rxrpc_call(call, op, n, here, NULL);
465}
466
467/*
468 * Detach a call from its owning socket.
469 */
470void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
471{
472	const void *here = __builtin_return_address(0);
473	struct rxrpc_connection *conn = call->conn;
474	bool put = false;
475	int i;
476
477	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
478
479	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
480			 here, (const void *)call->flags);
481
482	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 
483
484	spin_lock_bh(&call->lock);
485	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
486		BUG();
487	spin_unlock_bh(&call->lock);
488
489	del_timer_sync(&call->timer);
490
491	/* Make sure we don't get any more notifications */
492	write_lock_bh(&rx->recvmsg_lock);
493
494	if (!list_empty(&call->recvmsg_link)) {
495		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
496		       call, call->events, call->flags);
497		list_del(&call->recvmsg_link);
498		put = true;
499	}
500
501	/* list_empty() must return false in rxrpc_notify_socket() */
502	call->recvmsg_link.next = NULL;
503	call->recvmsg_link.prev = NULL;
504
505	write_unlock_bh(&rx->recvmsg_lock);
506	if (put)
507		rxrpc_put_call(call, rxrpc_call_put);
508
509	write_lock(&rx->call_lock);
510
511	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
512		rb_erase(&call->sock_node, &rx->calls);
513		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
514		rxrpc_put_call(call, rxrpc_call_put_userid);
515	}
516
517	list_del(&call->sock_link);
518	write_unlock(&rx->call_lock);
519
520	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
521
522	if (conn)
523		rxrpc_disconnect_call(call);
524
525	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
526		rxrpc_free_skb(call->rxtx_buffer[i],
527			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
528				rxrpc_skb_rx_cleaned));
529		call->rxtx_buffer[i] = NULL;
530	}
531
532	_leave("");
533}
534
535/*
536 * Prepare a kernel service call for retry.
537 */
538int rxrpc_prepare_call_for_retry(struct rxrpc_sock *rx, struct rxrpc_call *call)
539{
540	const void *here = __builtin_return_address(0);
541	int i;
542	u8 last = 0;
543
544	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
545
546	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
547			 here, (const void *)call->flags);
548
549	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
550	ASSERTCMP(call->completion, !=, RXRPC_CALL_REMOTELY_ABORTED);
551	ASSERTCMP(call->completion, !=, RXRPC_CALL_LOCALLY_ABORTED);
552	ASSERT(list_empty(&call->recvmsg_link));
553
554	del_timer_sync(&call->timer);
555
556	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, call->conn);
557
558	if (call->conn)
559		rxrpc_disconnect_call(call);
560
561	if (rxrpc_is_service_call(call) ||
562	    !call->tx_phase ||
563	    call->tx_hard_ack != 0 ||
564	    call->rx_hard_ack != 0 ||
565	    call->rx_top != 0)
566		return -EINVAL;
567
568	call->state = RXRPC_CALL_UNINITIALISED;
569	call->completion = RXRPC_CALL_SUCCEEDED;
570	call->call_id = 0;
571	call->cid = 0;
572	call->cong_cwnd = 0;
573	call->cong_extra = 0;
574	call->cong_ssthresh = 0;
575	call->cong_mode = 0;
576	call->cong_dup_acks = 0;
577	call->cong_cumul_acks = 0;
578	call->acks_lowest_nak = 0;
579
580	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
581		last |= call->rxtx_annotations[i];
582		call->rxtx_annotations[i] &= RXRPC_TX_ANNO_LAST;
583		call->rxtx_annotations[i] |= RXRPC_TX_ANNO_RETRANS;
584	}
585
586	_leave(" = 0");
587	return 0;
588}
589
590/*
591 * release all the calls associated with a socket
592 */
593void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
594{
595	struct rxrpc_call *call;
596
597	_enter("%p", rx);
598
599	while (!list_empty(&rx->to_be_accepted)) {
600		call = list_entry(rx->to_be_accepted.next,
601				  struct rxrpc_call, accept_link);
602		list_del(&call->accept_link);
603		rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
604		rxrpc_put_call(call, rxrpc_call_put);
 
605	}
606
607	while (!list_empty(&rx->sock_calls)) {
608		call = list_entry(rx->sock_calls.next,
609				  struct rxrpc_call, sock_link);
610		rxrpc_get_call(call, rxrpc_call_got);
611		rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
612		rxrpc_send_abort_packet(call);
613		rxrpc_release_call(rx, call);
614		rxrpc_put_call(call, rxrpc_call_put);
615	}
616
617	_leave("");
618}
619
620/*
621 * release a call
622 */
623void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
624{
625	struct rxrpc_net *rxnet = call->rxnet;
626	const void *here = __builtin_return_address(0);
627	int n;
 
628
629	ASSERT(call != NULL);
630
631	n = atomic_dec_return(&call->usage);
632	trace_rxrpc_call(call, op, n, here, NULL);
633	ASSERTCMP(n, >=, 0);
634	if (n == 0) {
635		_debug("call %d dead", call->debug_id);
636		ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
637
638		if (!list_empty(&call->link)) {
639			write_lock(&rxnet->call_lock);
640			list_del_init(&call->link);
641			write_unlock(&rxnet->call_lock);
642		}
643
644		rxrpc_cleanup_call(call);
645	}
646}
647
648/*
649 * Final call destruction under RCU.
650 */
651static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
652{
653	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
654	struct rxrpc_net *rxnet = call->rxnet;
655
656	rxrpc_put_peer(call->peer);
657	kfree(call->rxtx_buffer);
658	kfree(call->rxtx_annotations);
659	kmem_cache_free(rxrpc_call_jar, call);
660	if (atomic_dec_and_test(&rxnet->nr_calls))
661		wake_up_var(&rxnet->nr_calls);
662}
663
664/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
665 * clean up a call
666 */
667void rxrpc_cleanup_call(struct rxrpc_call *call)
668{
669	int i;
670
671	_net("DESTROY CALL %d", call->debug_id);
672
673	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
674
675	del_timer_sync(&call->timer);
676
677	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
678	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
679	ASSERTCMP(call->conn, ==, NULL);
680
681	/* Clean up the Rx/Tx buffer */
682	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
683		rxrpc_free_skb(call->rxtx_buffer[i],
684			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
685				rxrpc_skb_rx_cleaned));
686
687	rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
688
689	call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
 
 
 
 
690}
691
692/*
693 * Make sure that all calls are gone from a network namespace.  To reach this
694 * point, any open UDP sockets in that namespace must have been closed, so any
695 * outstanding calls cannot be doing I/O.
696 */
697void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
698{
699	struct rxrpc_call *call;
700
701	_enter("");
702
703	if (list_empty(&rxnet->calls))
704		return;
705
706	write_lock(&rxnet->call_lock);
 
 
 
707
708	while (!list_empty(&rxnet->calls)) {
709		call = list_entry(rxnet->calls.next, struct rxrpc_call, link);
710		_debug("Zapping call %p", call);
711
712		rxrpc_see_call(call);
713		list_del_init(&call->link);
 
 
 
 
 
 
 
714
715		pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
716		       call, atomic_read(&call->usage),
717		       rxrpc_call_states[call->state],
718		       call->flags, call->events);
719
720		write_unlock(&rxnet->call_lock);
721		cond_resched();
722		write_lock(&rxnet->call_lock);
723	}
724
725	write_unlock(&rxnet->call_lock);
726
727	atomic_dec(&rxnet->nr_calls);
728	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
729}