xref: /linux/net/rxrpc/call_object.c (revision 5b0e2cb020085efe202123162502e0b551e49a0e)
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 
22 const 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 
38 const 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 
46 struct kmem_cache *rxrpc_call_jar;
47 
48 static void rxrpc_call_timer_expired(unsigned long _call)
49 {
50 	struct rxrpc_call *call = (struct rxrpc_call *)_call;
51 
52 	_enter("%d", call->debug_id);
53 
54 	if (call->state < RXRPC_CALL_COMPLETE)
55 		rxrpc_set_timer(call, rxrpc_timer_expired, ktime_get_real());
56 }
57 
58 /*
59  * find an extant server call
60  * - called in process context with IRQs enabled
61  */
62 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
63 					      unsigned long user_call_ID)
64 {
65 	struct rxrpc_call *call;
66 	struct rb_node *p;
67 
68 	_enter("%p,%lx", rx, user_call_ID);
69 
70 	read_lock(&rx->call_lock);
71 
72 	p = rx->calls.rb_node;
73 	while (p) {
74 		call = rb_entry(p, struct rxrpc_call, sock_node);
75 
76 		if (user_call_ID < call->user_call_ID)
77 			p = p->rb_left;
78 		else if (user_call_ID > call->user_call_ID)
79 			p = p->rb_right;
80 		else
81 			goto found_extant_call;
82 	}
83 
84 	read_unlock(&rx->call_lock);
85 	_leave(" = NULL");
86 	return NULL;
87 
88 found_extant_call:
89 	rxrpc_get_call(call, rxrpc_call_got);
90 	read_unlock(&rx->call_lock);
91 	_leave(" = %p [%d]", call, atomic_read(&call->usage));
92 	return call;
93 }
94 
95 /*
96  * allocate a new call
97  */
98 struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
99 {
100 	struct rxrpc_call *call;
101 
102 	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
103 	if (!call)
104 		return NULL;
105 
106 	call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
107 				    sizeof(struct sk_buff *),
108 				    gfp);
109 	if (!call->rxtx_buffer)
110 		goto nomem;
111 
112 	call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
113 	if (!call->rxtx_annotations)
114 		goto nomem_2;
115 
116 	mutex_init(&call->user_mutex);
117 	setup_timer(&call->timer, rxrpc_call_timer_expired,
118 		    (unsigned long)call);
119 	INIT_WORK(&call->processor, &rxrpc_process_call);
120 	INIT_LIST_HEAD(&call->link);
121 	INIT_LIST_HEAD(&call->chan_wait_link);
122 	INIT_LIST_HEAD(&call->accept_link);
123 	INIT_LIST_HEAD(&call->recvmsg_link);
124 	INIT_LIST_HEAD(&call->sock_link);
125 	init_waitqueue_head(&call->waitq);
126 	spin_lock_init(&call->lock);
127 	spin_lock_init(&call->notify_lock);
128 	rwlock_init(&call->state_lock);
129 	atomic_set(&call->usage, 1);
130 	call->debug_id = atomic_inc_return(&rxrpc_debug_id);
131 	call->tx_total_len = -1;
132 
133 	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
134 
135 	/* Leave space in the ring to handle a maxed-out jumbo packet */
136 	call->rx_winsize = rxrpc_rx_window_size;
137 	call->tx_winsize = 16;
138 	call->rx_expect_next = 1;
139 
140 	call->cong_cwnd = 2;
141 	call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
142 	return call;
143 
144 nomem_2:
145 	kfree(call->rxtx_buffer);
146 nomem:
147 	kmem_cache_free(rxrpc_call_jar, call);
148 	return NULL;
149 }
150 
151 /*
152  * Allocate a new client call.
153  */
154 static struct rxrpc_call *rxrpc_alloc_client_call(struct sockaddr_rxrpc *srx,
155 						  gfp_t gfp)
156 {
157 	struct rxrpc_call *call;
158 	ktime_t now;
159 
160 	_enter("");
161 
162 	call = rxrpc_alloc_call(gfp);
163 	if (!call)
164 		return ERR_PTR(-ENOMEM);
165 	call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
166 	call->service_id = srx->srx_service;
167 	call->tx_phase = true;
168 	now = ktime_get_real();
169 	call->acks_latest_ts = now;
170 	call->cong_tstamp = now;
171 
172 	_leave(" = %p", call);
173 	return call;
174 }
175 
176 /*
177  * Initiate the call ack/resend/expiry timer.
178  */
179 static void rxrpc_start_call_timer(struct rxrpc_call *call)
180 {
181 	ktime_t now = ktime_get_real(), expire_at;
182 
183 	expire_at = ktime_add_ms(now, rxrpc_max_call_lifetime);
184 	call->expire_at = expire_at;
185 	call->ack_at = expire_at;
186 	call->ping_at = expire_at;
187 	call->resend_at = expire_at;
188 	call->timer.expires = jiffies + LONG_MAX / 2;
189 	rxrpc_set_timer(call, rxrpc_timer_begin, now);
190 }
191 
192 /*
193  * Set up a call for the given parameters.
194  * - Called with the socket lock held, which it must release.
195  * - If it returns a call, the call's lock will need releasing by the caller.
196  */
197 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
198 					 struct rxrpc_conn_parameters *cp,
199 					 struct sockaddr_rxrpc *srx,
200 					 unsigned long user_call_ID,
201 					 s64 tx_total_len,
202 					 gfp_t gfp)
203 	__releases(&rx->sk.sk_lock.slock)
204 {
205 	struct rxrpc_call *call, *xcall;
206 	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
207 	struct rb_node *parent, **pp;
208 	const void *here = __builtin_return_address(0);
209 	int ret;
210 
211 	_enter("%p,%lx", rx, user_call_ID);
212 
213 	call = rxrpc_alloc_client_call(srx, gfp);
214 	if (IS_ERR(call)) {
215 		release_sock(&rx->sk);
216 		_leave(" = %ld", PTR_ERR(call));
217 		return call;
218 	}
219 
220 	call->tx_total_len = tx_total_len;
221 	trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
222 			 here, (const void *)user_call_ID);
223 
224 	/* We need to protect a partially set up call against the user as we
225 	 * will be acting outside the socket lock.
226 	 */
227 	mutex_lock(&call->user_mutex);
228 
229 	/* Publish the call, even though it is incompletely set up as yet */
230 	write_lock(&rx->call_lock);
231 
232 	pp = &rx->calls.rb_node;
233 	parent = NULL;
234 	while (*pp) {
235 		parent = *pp;
236 		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
237 
238 		if (user_call_ID < xcall->user_call_ID)
239 			pp = &(*pp)->rb_left;
240 		else if (user_call_ID > xcall->user_call_ID)
241 			pp = &(*pp)->rb_right;
242 		else
243 			goto error_dup_user_ID;
244 	}
245 
246 	rcu_assign_pointer(call->socket, rx);
247 	call->user_call_ID = user_call_ID;
248 	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
249 	rxrpc_get_call(call, rxrpc_call_got_userid);
250 	rb_link_node(&call->sock_node, parent, pp);
251 	rb_insert_color(&call->sock_node, &rx->calls);
252 	list_add(&call->sock_link, &rx->sock_calls);
253 
254 	write_unlock(&rx->call_lock);
255 
256 	write_lock(&rxnet->call_lock);
257 	list_add_tail(&call->link, &rxnet->calls);
258 	write_unlock(&rxnet->call_lock);
259 
260 	/* From this point on, the call is protected by its own lock. */
261 	release_sock(&rx->sk);
262 
263 	/* Set up or get a connection record and set the protocol parameters,
264 	 * including channel number and call ID.
265 	 */
266 	ret = rxrpc_connect_call(call, cp, srx, gfp);
267 	if (ret < 0)
268 		goto error;
269 
270 	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
271 			 here, NULL);
272 
273 	rxrpc_start_call_timer(call);
274 
275 	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
276 
277 	_leave(" = %p [new]", call);
278 	return call;
279 
280 	/* We unexpectedly found the user ID in the list after taking
281 	 * the call_lock.  This shouldn't happen unless the user races
282 	 * with itself and tries to add the same user ID twice at the
283 	 * same time in different threads.
284 	 */
285 error_dup_user_ID:
286 	write_unlock(&rx->call_lock);
287 	release_sock(&rx->sk);
288 	ret = -EEXIST;
289 
290 error:
291 	__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
292 				    RX_CALL_DEAD, ret);
293 	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
294 			 here, ERR_PTR(ret));
295 	rxrpc_release_call(rx, call);
296 	mutex_unlock(&call->user_mutex);
297 	rxrpc_put_call(call, rxrpc_call_put);
298 	_leave(" = %d", ret);
299 	return ERR_PTR(ret);
300 }
301 
302 /*
303  * Retry a call to a new address.  It is expected that the Tx queue of the call
304  * will contain data previously packaged for an old call.
305  */
306 int rxrpc_retry_client_call(struct rxrpc_sock *rx,
307 			    struct rxrpc_call *call,
308 			    struct rxrpc_conn_parameters *cp,
309 			    struct sockaddr_rxrpc *srx,
310 			    gfp_t gfp)
311 {
312 	const void *here = __builtin_return_address(0);
313 	int ret;
314 
315 	/* Set up or get a connection record and set the protocol parameters,
316 	 * including channel number and call ID.
317 	 */
318 	ret = rxrpc_connect_call(call, cp, srx, gfp);
319 	if (ret < 0)
320 		goto error;
321 
322 	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
323 			 here, NULL);
324 
325 	rxrpc_start_call_timer(call);
326 
327 	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
328 
329 	if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
330 		rxrpc_queue_call(call);
331 
332 	_leave(" = 0");
333 	return 0;
334 
335 error:
336 	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
337 				  RX_CALL_DEAD, ret);
338 	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
339 			 here, ERR_PTR(ret));
340 	_leave(" = %d", ret);
341 	return ret;
342 }
343 
344 /*
345  * Set up an incoming call.  call->conn points to the connection.
346  * This is called in BH context and isn't allowed to fail.
347  */
348 void rxrpc_incoming_call(struct rxrpc_sock *rx,
349 			 struct rxrpc_call *call,
350 			 struct sk_buff *skb)
351 {
352 	struct rxrpc_connection *conn = call->conn;
353 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
354 	u32 chan;
355 
356 	_enter(",%d", call->conn->debug_id);
357 
358 	rcu_assign_pointer(call->socket, rx);
359 	call->call_id		= sp->hdr.callNumber;
360 	call->service_id	= sp->hdr.serviceId;
361 	call->cid		= sp->hdr.cid;
362 	call->state		= RXRPC_CALL_SERVER_ACCEPTING;
363 	if (sp->hdr.securityIndex > 0)
364 		call->state	= RXRPC_CALL_SERVER_SECURING;
365 	call->cong_tstamp	= skb->tstamp;
366 
367 	/* Set the channel for this call.  We don't get channel_lock as we're
368 	 * only defending against the data_ready handler (which we're called
369 	 * from) and the RESPONSE packet parser (which is only really
370 	 * interested in call_counter and can cope with a disagreement with the
371 	 * call pointer).
372 	 */
373 	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
374 	conn->channels[chan].call_counter = call->call_id;
375 	conn->channels[chan].call_id = call->call_id;
376 	rcu_assign_pointer(conn->channels[chan].call, call);
377 
378 	spin_lock(&conn->params.peer->lock);
379 	hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
380 	spin_unlock(&conn->params.peer->lock);
381 
382 	_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
383 
384 	rxrpc_start_call_timer(call);
385 	_leave("");
386 }
387 
388 /*
389  * Queue a call's work processor, getting a ref to pass to the work queue.
390  */
391 bool rxrpc_queue_call(struct rxrpc_call *call)
392 {
393 	const void *here = __builtin_return_address(0);
394 	int n = __atomic_add_unless(&call->usage, 1, 0);
395 	if (n == 0)
396 		return false;
397 	if (rxrpc_queue_work(&call->processor))
398 		trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
399 	else
400 		rxrpc_put_call(call, rxrpc_call_put_noqueue);
401 	return true;
402 }
403 
404 /*
405  * Queue a call's work processor, passing the callers ref to the work queue.
406  */
407 bool __rxrpc_queue_call(struct rxrpc_call *call)
408 {
409 	const void *here = __builtin_return_address(0);
410 	int n = atomic_read(&call->usage);
411 	ASSERTCMP(n, >=, 1);
412 	if (rxrpc_queue_work(&call->processor))
413 		trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
414 	else
415 		rxrpc_put_call(call, rxrpc_call_put_noqueue);
416 	return true;
417 }
418 
419 /*
420  * Note the re-emergence of a call.
421  */
422 void rxrpc_see_call(struct rxrpc_call *call)
423 {
424 	const void *here = __builtin_return_address(0);
425 	if (call) {
426 		int n = atomic_read(&call->usage);
427 
428 		trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
429 	}
430 }
431 
432 /*
433  * Note the addition of a ref on a call.
434  */
435 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
436 {
437 	const void *here = __builtin_return_address(0);
438 	int n = atomic_inc_return(&call->usage);
439 
440 	trace_rxrpc_call(call, op, n, here, NULL);
441 }
442 
443 /*
444  * Detach a call from its owning socket.
445  */
446 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
447 {
448 	const void *here = __builtin_return_address(0);
449 	struct rxrpc_connection *conn = call->conn;
450 	bool put = false;
451 	int i;
452 
453 	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
454 
455 	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
456 			 here, (const void *)call->flags);
457 
458 	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
459 
460 	spin_lock_bh(&call->lock);
461 	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
462 		BUG();
463 	spin_unlock_bh(&call->lock);
464 
465 	del_timer_sync(&call->timer);
466 
467 	/* Make sure we don't get any more notifications */
468 	write_lock_bh(&rx->recvmsg_lock);
469 
470 	if (!list_empty(&call->recvmsg_link)) {
471 		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
472 		       call, call->events, call->flags);
473 		list_del(&call->recvmsg_link);
474 		put = true;
475 	}
476 
477 	/* list_empty() must return false in rxrpc_notify_socket() */
478 	call->recvmsg_link.next = NULL;
479 	call->recvmsg_link.prev = NULL;
480 
481 	write_unlock_bh(&rx->recvmsg_lock);
482 	if (put)
483 		rxrpc_put_call(call, rxrpc_call_put);
484 
485 	write_lock(&rx->call_lock);
486 
487 	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
488 		rb_erase(&call->sock_node, &rx->calls);
489 		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
490 		rxrpc_put_call(call, rxrpc_call_put_userid);
491 	}
492 
493 	list_del(&call->sock_link);
494 	write_unlock(&rx->call_lock);
495 
496 	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
497 
498 	if (conn)
499 		rxrpc_disconnect_call(call);
500 
501 	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
502 		rxrpc_free_skb(call->rxtx_buffer[i],
503 			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
504 				rxrpc_skb_rx_cleaned));
505 		call->rxtx_buffer[i] = NULL;
506 	}
507 
508 	_leave("");
509 }
510 
511 /*
512  * Prepare a kernel service call for retry.
513  */
514 int rxrpc_prepare_call_for_retry(struct rxrpc_sock *rx, struct rxrpc_call *call)
515 {
516 	const void *here = __builtin_return_address(0);
517 	int i;
518 	u8 last = 0;
519 
520 	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
521 
522 	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
523 			 here, (const void *)call->flags);
524 
525 	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
526 	ASSERTCMP(call->completion, !=, RXRPC_CALL_REMOTELY_ABORTED);
527 	ASSERTCMP(call->completion, !=, RXRPC_CALL_LOCALLY_ABORTED);
528 	ASSERT(list_empty(&call->recvmsg_link));
529 
530 	del_timer_sync(&call->timer);
531 
532 	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, call->conn);
533 
534 	if (call->conn)
535 		rxrpc_disconnect_call(call);
536 
537 	if (rxrpc_is_service_call(call) ||
538 	    !call->tx_phase ||
539 	    call->tx_hard_ack != 0 ||
540 	    call->rx_hard_ack != 0 ||
541 	    call->rx_top != 0)
542 		return -EINVAL;
543 
544 	call->state = RXRPC_CALL_UNINITIALISED;
545 	call->completion = RXRPC_CALL_SUCCEEDED;
546 	call->call_id = 0;
547 	call->cid = 0;
548 	call->cong_cwnd = 0;
549 	call->cong_extra = 0;
550 	call->cong_ssthresh = 0;
551 	call->cong_mode = 0;
552 	call->cong_dup_acks = 0;
553 	call->cong_cumul_acks = 0;
554 	call->acks_lowest_nak = 0;
555 
556 	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
557 		last |= call->rxtx_annotations[i];
558 		call->rxtx_annotations[i] &= RXRPC_TX_ANNO_LAST;
559 		call->rxtx_annotations[i] |= RXRPC_TX_ANNO_RETRANS;
560 	}
561 
562 	_leave(" = 0");
563 	return 0;
564 }
565 
566 /*
567  * release all the calls associated with a socket
568  */
569 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
570 {
571 	struct rxrpc_call *call;
572 
573 	_enter("%p", rx);
574 
575 	while (!list_empty(&rx->to_be_accepted)) {
576 		call = list_entry(rx->to_be_accepted.next,
577 				  struct rxrpc_call, accept_link);
578 		list_del(&call->accept_link);
579 		rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
580 		rxrpc_put_call(call, rxrpc_call_put);
581 	}
582 
583 	while (!list_empty(&rx->sock_calls)) {
584 		call = list_entry(rx->sock_calls.next,
585 				  struct rxrpc_call, sock_link);
586 		rxrpc_get_call(call, rxrpc_call_got);
587 		rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
588 		rxrpc_send_abort_packet(call);
589 		rxrpc_release_call(rx, call);
590 		rxrpc_put_call(call, rxrpc_call_put);
591 	}
592 
593 	_leave("");
594 }
595 
596 /*
597  * release a call
598  */
599 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
600 {
601 	struct rxrpc_net *rxnet;
602 	const void *here = __builtin_return_address(0);
603 	int n;
604 
605 	ASSERT(call != NULL);
606 
607 	n = atomic_dec_return(&call->usage);
608 	trace_rxrpc_call(call, op, n, here, NULL);
609 	ASSERTCMP(n, >=, 0);
610 	if (n == 0) {
611 		_debug("call %d dead", call->debug_id);
612 		ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
613 
614 		if (!list_empty(&call->link)) {
615 			rxnet = rxrpc_net(sock_net(&call->socket->sk));
616 			write_lock(&rxnet->call_lock);
617 			list_del_init(&call->link);
618 			write_unlock(&rxnet->call_lock);
619 		}
620 
621 		rxrpc_cleanup_call(call);
622 	}
623 }
624 
625 /*
626  * Final call destruction under RCU.
627  */
628 static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
629 {
630 	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
631 
632 	rxrpc_put_peer(call->peer);
633 	kfree(call->rxtx_buffer);
634 	kfree(call->rxtx_annotations);
635 	kmem_cache_free(rxrpc_call_jar, call);
636 }
637 
638 /*
639  * clean up a call
640  */
641 void rxrpc_cleanup_call(struct rxrpc_call *call)
642 {
643 	int i;
644 
645 	_net("DESTROY CALL %d", call->debug_id);
646 
647 	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
648 
649 	del_timer_sync(&call->timer);
650 
651 	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
652 	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
653 	ASSERTCMP(call->conn, ==, NULL);
654 
655 	/* Clean up the Rx/Tx buffer */
656 	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
657 		rxrpc_free_skb(call->rxtx_buffer[i],
658 			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
659 				rxrpc_skb_rx_cleaned));
660 
661 	rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
662 
663 	call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
664 }
665 
666 /*
667  * Make sure that all calls are gone from a network namespace.  To reach this
668  * point, any open UDP sockets in that namespace must have been closed, so any
669  * outstanding calls cannot be doing I/O.
670  */
671 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
672 {
673 	struct rxrpc_call *call;
674 
675 	_enter("");
676 
677 	if (list_empty(&rxnet->calls))
678 		return;
679 
680 	write_lock(&rxnet->call_lock);
681 
682 	while (!list_empty(&rxnet->calls)) {
683 		call = list_entry(rxnet->calls.next, struct rxrpc_call, link);
684 		_debug("Zapping call %p", call);
685 
686 		rxrpc_see_call(call);
687 		list_del_init(&call->link);
688 
689 		pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
690 		       call, atomic_read(&call->usage),
691 		       rxrpc_call_states[call->state],
692 		       call->flags, call->events);
693 
694 		write_unlock(&rxnet->call_lock);
695 		cond_resched();
696 		write_lock(&rxnet->call_lock);
697 	}
698 
699 	write_unlock(&rxnet->call_lock);
700 }
701