xref: /openbmc/linux/net/rxrpc/call_object.c (revision 8ffd3d5e)
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 
18 const 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 
33 const 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 
41 struct kmem_cache *rxrpc_call_jar;
42 
43 static struct semaphore rxrpc_call_limiter =
44 	__SEMAPHORE_INITIALIZER(rxrpc_call_limiter, 1000);
45 static struct semaphore rxrpc_kernel_call_limiter =
46 	__SEMAPHORE_INITIALIZER(rxrpc_kernel_call_limiter, 1000);
47 
48 void 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 (call->state < RXRPC_CALL_COMPLETE) {
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 
66 static 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 (call->state < RXRPC_CALL_COMPLETE) {
73 		trace_rxrpc_timer_expired(call, jiffies);
74 		rxrpc_poke_call(call, rxrpc_call_poke_timer);
75 	}
76 }
77 
78 void 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 
87 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
88 
89 static void rxrpc_destroy_call(struct work_struct *);
90 
91 /*
92  * find an extant server call
93  * - called in process context with IRQs enabled
94  */
95 struct 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 
121 found_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  */
131 struct 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->chan_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 	rwlock_init(&call->state_lock);
166 	refcount_set(&call->ref, 1);
167 	call->debug_id = debug_id;
168 	call->tx_total_len = -1;
169 	call->next_rx_timo = 20 * HZ;
170 	call->next_req_timo = 1 * HZ;
171 	atomic64_set(&call->ackr_window, 0x100000001ULL);
172 
173 	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
174 
175 	call->rx_winsize = rxrpc_rx_window_size;
176 	call->tx_winsize = 16;
177 
178 	if (RXRPC_TX_SMSS > 2190)
179 		call->cong_cwnd = 2;
180 	else if (RXRPC_TX_SMSS > 1095)
181 		call->cong_cwnd = 3;
182 	else
183 		call->cong_cwnd = 4;
184 	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
185 
186 	call->rxnet = rxnet;
187 	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
188 	atomic_inc(&rxnet->nr_calls);
189 	return call;
190 }
191 
192 /*
193  * Allocate a new client call.
194  */
195 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
196 						  struct sockaddr_rxrpc *srx,
197 						  struct rxrpc_conn_parameters *cp,
198 						  struct rxrpc_call_params *p,
199 						  gfp_t gfp,
200 						  unsigned int debug_id)
201 {
202 	struct rxrpc_call *call;
203 	ktime_t now;
204 	int ret;
205 
206 	_enter("");
207 
208 	call = rxrpc_alloc_call(rx, gfp, debug_id);
209 	if (!call)
210 		return ERR_PTR(-ENOMEM);
211 	now = ktime_get_real();
212 	call->acks_latest_ts	= now;
213 	call->cong_tstamp	= now;
214 	call->state		= RXRPC_CALL_CLIENT_AWAIT_CONN;
215 	call->dest_srx		= *srx;
216 	call->interruptibility	= p->interruptibility;
217 	call->tx_total_len	= p->tx_total_len;
218 	call->key		= key_get(cp->key);
219 	call->local		= rxrpc_get_local(cp->local, rxrpc_local_get_call);
220 	call->security_level	= cp->security_level;
221 	if (p->kernel)
222 		__set_bit(RXRPC_CALL_KERNEL, &call->flags);
223 	if (cp->upgrade)
224 		__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
225 	if (cp->exclusive)
226 		__set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
227 
228 	ret = rxrpc_init_client_call_security(call);
229 	if (ret < 0) {
230 		__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
231 		rxrpc_put_call(call, rxrpc_call_put_discard_error);
232 		return ERR_PTR(ret);
233 	}
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  */
245 static void 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  */
264 static 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  */
280 static 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  * Set up a call for the given parameters.
291  * - Called with the socket lock held, which it must release.
292  * - If it returns a call, the call's lock will need releasing by the caller.
293  */
294 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
295 					 struct rxrpc_conn_parameters *cp,
296 					 struct sockaddr_rxrpc *srx,
297 					 struct rxrpc_call_params *p,
298 					 gfp_t gfp,
299 					 unsigned int debug_id)
300 	__releases(&rx->sk.sk_lock.slock)
301 	__acquires(&call->user_mutex)
302 {
303 	struct rxrpc_call *call, *xcall;
304 	struct rxrpc_net *rxnet;
305 	struct semaphore *limiter;
306 	struct rb_node *parent, **pp;
307 	int ret;
308 
309 	_enter("%p,%lx", rx, p->user_call_ID);
310 
311 	limiter = rxrpc_get_call_slot(p, gfp);
312 	if (!limiter) {
313 		release_sock(&rx->sk);
314 		return ERR_PTR(-ERESTARTSYS);
315 	}
316 
317 	call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id);
318 	if (IS_ERR(call)) {
319 		release_sock(&rx->sk);
320 		up(limiter);
321 		_leave(" = %ld", PTR_ERR(call));
322 		return call;
323 	}
324 
325 	/* We need to protect a partially set up call against the user as we
326 	 * will be acting outside the socket lock.
327 	 */
328 	mutex_lock(&call->user_mutex);
329 
330 	/* Publish the call, even though it is incompletely set up as yet */
331 	write_lock(&rx->call_lock);
332 
333 	pp = &rx->calls.rb_node;
334 	parent = NULL;
335 	while (*pp) {
336 		parent = *pp;
337 		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
338 
339 		if (p->user_call_ID < xcall->user_call_ID)
340 			pp = &(*pp)->rb_left;
341 		else if (p->user_call_ID > xcall->user_call_ID)
342 			pp = &(*pp)->rb_right;
343 		else
344 			goto error_dup_user_ID;
345 	}
346 
347 	rcu_assign_pointer(call->socket, rx);
348 	call->user_call_ID = p->user_call_ID;
349 	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
350 	rxrpc_get_call(call, rxrpc_call_get_userid);
351 	rb_link_node(&call->sock_node, parent, pp);
352 	rb_insert_color(&call->sock_node, &rx->calls);
353 	list_add(&call->sock_link, &rx->sock_calls);
354 
355 	write_unlock(&rx->call_lock);
356 
357 	rxnet = call->rxnet;
358 	spin_lock(&rxnet->call_lock);
359 	list_add_tail_rcu(&call->link, &rxnet->calls);
360 	spin_unlock(&rxnet->call_lock);
361 
362 	/* From this point on, the call is protected by its own lock. */
363 	release_sock(&rx->sk);
364 
365 	/* Set up or get a connection record and set the protocol parameters,
366 	 * including channel number and call ID.
367 	 */
368 	ret = rxrpc_connect_call(rx, call, cp, srx, gfp);
369 	if (ret < 0)
370 		goto error_attached_to_socket;
371 
372 	rxrpc_see_call(call, rxrpc_call_see_connected);
373 
374 	rxrpc_start_call_timer(call);
375 
376 	_leave(" = %p [new]", call);
377 	return call;
378 
379 	/* We unexpectedly found the user ID in the list after taking
380 	 * the call_lock.  This shouldn't happen unless the user races
381 	 * with itself and tries to add the same user ID twice at the
382 	 * same time in different threads.
383 	 */
384 error_dup_user_ID:
385 	write_unlock(&rx->call_lock);
386 	release_sock(&rx->sk);
387 	__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
388 				    RX_CALL_DEAD, -EEXIST);
389 	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
390 			 rxrpc_call_see_userid_exists);
391 	rxrpc_release_call(rx, call);
392 	mutex_unlock(&call->user_mutex);
393 	rxrpc_put_call(call, rxrpc_call_put_userid_exists);
394 	_leave(" = -EEXIST");
395 	return ERR_PTR(-EEXIST);
396 
397 	/* We got an error, but the call is attached to the socket and is in
398 	 * need of release.  However, we might now race with recvmsg() when
399 	 * completing the call queues it.  Return 0 from sys_sendmsg() and
400 	 * leave the error to recvmsg() to deal with.
401 	 */
402 error_attached_to_socket:
403 	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
404 			 rxrpc_call_see_connect_failed);
405 	set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
406 	__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
407 				    RX_CALL_DEAD, ret);
408 	_leave(" = c=%08x [err]", call->debug_id);
409 	return call;
410 }
411 
412 /*
413  * Set up an incoming call.  call->conn points to the connection.
414  * This is called in BH context and isn't allowed to fail.
415  */
416 void rxrpc_incoming_call(struct rxrpc_sock *rx,
417 			 struct rxrpc_call *call,
418 			 struct sk_buff *skb)
419 {
420 	struct rxrpc_connection *conn = call->conn;
421 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
422 	u32 chan;
423 
424 	_enter(",%d", call->conn->debug_id);
425 
426 	rcu_assign_pointer(call->socket, rx);
427 	call->call_id		= sp->hdr.callNumber;
428 	call->dest_srx.srx_service = sp->hdr.serviceId;
429 	call->cid		= sp->hdr.cid;
430 	call->state		= RXRPC_CALL_SERVER_SECURING;
431 	call->cong_tstamp	= skb->tstamp;
432 
433 	spin_lock(&conn->state_lock);
434 
435 	switch (conn->state) {
436 	case RXRPC_CONN_SERVICE_UNSECURED:
437 	case RXRPC_CONN_SERVICE_CHALLENGING:
438 		call->state = RXRPC_CALL_SERVER_SECURING;
439 		break;
440 	case RXRPC_CONN_SERVICE:
441 		call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
442 		break;
443 
444 	case RXRPC_CONN_REMOTELY_ABORTED:
445 		__rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
446 					    conn->abort_code, conn->error);
447 		break;
448 	case RXRPC_CONN_LOCALLY_ABORTED:
449 		__rxrpc_abort_call("CON", call, 1,
450 				   conn->abort_code, conn->error);
451 		break;
452 	default:
453 		BUG();
454 	}
455 
456 	/* Set the channel for this call.  We don't get channel_lock as we're
457 	 * only defending against the data_ready handler (which we're called
458 	 * from) and the RESPONSE packet parser (which is only really
459 	 * interested in call_counter and can cope with a disagreement with the
460 	 * call pointer).
461 	 */
462 	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
463 	conn->channels[chan].call_counter = call->call_id;
464 	conn->channels[chan].call_id = call->call_id;
465 	rcu_assign_pointer(conn->channels[chan].call, call);
466 	spin_unlock(&conn->state_lock);
467 
468 	spin_lock(&conn->peer->lock);
469 	hlist_add_head(&call->error_link, &conn->peer->error_targets);
470 	spin_unlock(&conn->peer->lock);
471 
472 	rxrpc_start_call_timer(call);
473 	_leave("");
474 }
475 
476 /*
477  * Note the re-emergence of a call.
478  */
479 void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
480 {
481 	if (call) {
482 		int r = refcount_read(&call->ref);
483 
484 		trace_rxrpc_call(call->debug_id, r, 0, why);
485 	}
486 }
487 
488 struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
489 				      enum rxrpc_call_trace why)
490 {
491 	int r;
492 
493 	if (!call || !__refcount_inc_not_zero(&call->ref, &r))
494 		return NULL;
495 	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
496 	return call;
497 }
498 
499 /*
500  * Note the addition of a ref on a call.
501  */
502 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
503 {
504 	int r;
505 
506 	__refcount_inc(&call->ref, &r);
507 	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
508 }
509 
510 /*
511  * Clean up the Rx skb ring.
512  */
513 static void rxrpc_cleanup_ring(struct rxrpc_call *call)
514 {
515 	skb_queue_purge(&call->recvmsg_queue);
516 	skb_queue_purge(&call->rx_oos_queue);
517 }
518 
519 /*
520  * Detach a call from its owning socket.
521  */
522 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
523 {
524 	struct rxrpc_connection *conn = call->conn;
525 	bool put = false;
526 
527 	_enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
528 
529 	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
530 			 call->flags, rxrpc_call_see_release);
531 
532 	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
533 
534 	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
535 		BUG();
536 
537 	rxrpc_put_call_slot(call);
538 	del_timer_sync(&call->timer);
539 
540 	/* Make sure we don't get any more notifications */
541 	write_lock(&rx->recvmsg_lock);
542 
543 	if (!list_empty(&call->recvmsg_link)) {
544 		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
545 		       call, call->events, call->flags);
546 		list_del(&call->recvmsg_link);
547 		put = true;
548 	}
549 
550 	/* list_empty() must return false in rxrpc_notify_socket() */
551 	call->recvmsg_link.next = NULL;
552 	call->recvmsg_link.prev = NULL;
553 
554 	write_unlock(&rx->recvmsg_lock);
555 	if (put)
556 		rxrpc_put_call(call, rxrpc_call_put_unnotify);
557 
558 	write_lock(&rx->call_lock);
559 
560 	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
561 		rb_erase(&call->sock_node, &rx->calls);
562 		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
563 		rxrpc_put_call(call, rxrpc_call_put_userid_exists);
564 	}
565 
566 	list_del(&call->sock_link);
567 	write_unlock(&rx->call_lock);
568 
569 	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
570 
571 	if (conn && !test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
572 		rxrpc_disconnect_call(call);
573 	if (call->security)
574 		call->security->free_call_crypto(call);
575 	_leave("");
576 }
577 
578 /*
579  * release all the calls associated with a socket
580  */
581 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
582 {
583 	struct rxrpc_call *call;
584 
585 	_enter("%p", rx);
586 
587 	while (!list_empty(&rx->to_be_accepted)) {
588 		call = list_entry(rx->to_be_accepted.next,
589 				  struct rxrpc_call, accept_link);
590 		list_del(&call->accept_link);
591 		rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
592 		rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
593 	}
594 
595 	while (!list_empty(&rx->sock_calls)) {
596 		call = list_entry(rx->sock_calls.next,
597 				  struct rxrpc_call, sock_link);
598 		rxrpc_get_call(call, rxrpc_call_get_release_sock);
599 		rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
600 		rxrpc_send_abort_packet(call);
601 		rxrpc_release_call(rx, call);
602 		rxrpc_put_call(call, rxrpc_call_put_release_sock);
603 	}
604 
605 	_leave("");
606 }
607 
608 /*
609  * release a call
610  */
611 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
612 {
613 	struct rxrpc_net *rxnet = call->rxnet;
614 	unsigned int debug_id = call->debug_id;
615 	bool dead;
616 	int r;
617 
618 	ASSERT(call != NULL);
619 
620 	dead = __refcount_dec_and_test(&call->ref, &r);
621 	trace_rxrpc_call(debug_id, r - 1, 0, why);
622 	if (dead) {
623 		ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
624 
625 		if (!list_empty(&call->link)) {
626 			spin_lock(&rxnet->call_lock);
627 			list_del_init(&call->link);
628 			spin_unlock(&rxnet->call_lock);
629 		}
630 
631 		rxrpc_cleanup_call(call);
632 	}
633 }
634 
635 /*
636  * Free up the call under RCU.
637  */
638 static void rxrpc_rcu_free_call(struct rcu_head *rcu)
639 {
640 	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
641 	struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
642 
643 	kmem_cache_free(rxrpc_call_jar, call);
644 	if (atomic_dec_and_test(&rxnet->nr_calls))
645 		wake_up_var(&rxnet->nr_calls);
646 }
647 
648 /*
649  * Final call destruction - but must be done in process context.
650  */
651 static void rxrpc_destroy_call(struct work_struct *work)
652 {
653 	struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
654 	struct rxrpc_txbuf *txb;
655 
656 	del_timer_sync(&call->timer);
657 
658 	rxrpc_cleanup_ring(call);
659 	while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
660 					       struct rxrpc_txbuf, call_link))) {
661 		list_del(&txb->call_link);
662 		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
663 	}
664 	while ((txb = list_first_entry_or_null(&call->tx_buffer,
665 					       struct rxrpc_txbuf, call_link))) {
666 		list_del(&txb->call_link);
667 		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
668 	}
669 
670 	rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
671 	rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
672 	rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
673 	rxrpc_put_local(call->local, rxrpc_local_put_call);
674 	call_rcu(&call->rcu, rxrpc_rcu_free_call);
675 }
676 
677 /*
678  * clean up a call
679  */
680 void rxrpc_cleanup_call(struct rxrpc_call *call)
681 {
682 	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
683 
684 	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
685 	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
686 
687 	del_timer(&call->timer);
688 
689 	if (rcu_read_lock_held())
690 		/* Can't use the rxrpc workqueue as we need to cancel/flush
691 		 * something that may be running/waiting there.
692 		 */
693 		schedule_work(&call->destroyer);
694 	else
695 		rxrpc_destroy_call(&call->destroyer);
696 }
697 
698 /*
699  * Make sure that all calls are gone from a network namespace.  To reach this
700  * point, any open UDP sockets in that namespace must have been closed, so any
701  * outstanding calls cannot be doing I/O.
702  */
703 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
704 {
705 	struct rxrpc_call *call;
706 
707 	_enter("");
708 
709 	if (!list_empty(&rxnet->calls)) {
710 		spin_lock(&rxnet->call_lock);
711 
712 		while (!list_empty(&rxnet->calls)) {
713 			call = list_entry(rxnet->calls.next,
714 					  struct rxrpc_call, link);
715 			_debug("Zapping call %p", call);
716 
717 			rxrpc_see_call(call, rxrpc_call_see_zap);
718 			list_del_init(&call->link);
719 
720 			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
721 			       call, refcount_read(&call->ref),
722 			       rxrpc_call_states[call->state],
723 			       call->flags, call->events);
724 
725 			spin_unlock(&rxnet->call_lock);
726 			cond_resched();
727 			spin_lock(&rxnet->call_lock);
728 		}
729 
730 		spin_unlock(&rxnet->call_lock);
731 	}
732 
733 	atomic_dec(&rxnet->nr_calls);
734 	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
735 }
736