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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_ACCEPTING] = "SvAccept",
27 [RXRPC_CALL_SERVER_RECV_REQUEST] = "SvRcvReq",
28 [RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq",
29 [RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl",
30 [RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK",
31 [RXRPC_CALL_COMPLETE] = "Complete",
32};
33
34const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
35 [RXRPC_CALL_SUCCEEDED] = "Complete",
36 [RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
37 [RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
38 [RXRPC_CALL_LOCAL_ERROR] = "LocError",
39 [RXRPC_CALL_NETWORK_ERROR] = "NetError",
40};
41
42struct kmem_cache *rxrpc_call_jar;
43
44static void rxrpc_call_timer_expired(struct timer_list *t)
45{
46 struct rxrpc_call *call = from_timer(call, t, timer);
47
48 _enter("%d", call->debug_id);
49
50 if (call->state < RXRPC_CALL_COMPLETE) {
51 trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
52 rxrpc_queue_call(call);
53 }
54}
55
56static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
57
58/*
59 * find an extant server call
60 * - called in process context with IRQs enabled
61 */
62struct 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
88found_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 */
98struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
99 unsigned int debug_id)
100{
101 struct rxrpc_call *call;
102 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
103
104 call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
105 if (!call)
106 return NULL;
107
108 call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
109 sizeof(struct sk_buff *),
110 gfp);
111 if (!call->rxtx_buffer)
112 goto nomem;
113
114 call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
115 if (!call->rxtx_annotations)
116 goto nomem_2;
117
118 mutex_init(&call->user_mutex);
119
120 /* Prevent lockdep reporting a deadlock false positive between the afs
121 * filesystem and sys_sendmsg() via the mmap sem.
122 */
123 if (rx->sk.sk_kern_sock)
124 lockdep_set_class(&call->user_mutex,
125 &rxrpc_call_user_mutex_lock_class_key);
126
127 timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
128 INIT_WORK(&call->processor, &rxrpc_process_call);
129 INIT_LIST_HEAD(&call->link);
130 INIT_LIST_HEAD(&call->chan_wait_link);
131 INIT_LIST_HEAD(&call->accept_link);
132 INIT_LIST_HEAD(&call->recvmsg_link);
133 INIT_LIST_HEAD(&call->sock_link);
134 init_waitqueue_head(&call->waitq);
135 spin_lock_init(&call->lock);
136 spin_lock_init(&call->notify_lock);
137 spin_lock_init(&call->input_lock);
138 rwlock_init(&call->state_lock);
139 atomic_set(&call->usage, 1);
140 call->debug_id = debug_id;
141 call->tx_total_len = -1;
142 call->next_rx_timo = 20 * HZ;
143 call->next_req_timo = 1 * HZ;
144
145 memset(&call->sock_node, 0xed, sizeof(call->sock_node));
146
147 /* Leave space in the ring to handle a maxed-out jumbo packet */
148 call->rx_winsize = rxrpc_rx_window_size;
149 call->tx_winsize = 16;
150 call->rx_expect_next = 1;
151
152 call->cong_cwnd = 2;
153 call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
154
155 call->rxnet = rxnet;
156 atomic_inc(&rxnet->nr_calls);
157 return call;
158
159nomem_2:
160 kfree(call->rxtx_buffer);
161nomem:
162 kmem_cache_free(rxrpc_call_jar, call);
163 return NULL;
164}
165
166/*
167 * Allocate a new client call.
168 */
169static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
170 struct sockaddr_rxrpc *srx,
171 gfp_t gfp,
172 unsigned int debug_id)
173{
174 struct rxrpc_call *call;
175 ktime_t now;
176
177 _enter("");
178
179 call = rxrpc_alloc_call(rx, gfp, debug_id);
180 if (!call)
181 return ERR_PTR(-ENOMEM);
182 call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
183 call->service_id = srx->srx_service;
184 call->tx_phase = true;
185 now = ktime_get_real();
186 call->acks_latest_ts = now;
187 call->cong_tstamp = now;
188
189 _leave(" = %p", call);
190 return call;
191}
192
193/*
194 * Initiate the call ack/resend/expiry timer.
195 */
196static void rxrpc_start_call_timer(struct rxrpc_call *call)
197{
198 unsigned long now = jiffies;
199 unsigned long j = now + MAX_JIFFY_OFFSET;
200
201 call->ack_at = j;
202 call->ack_lost_at = j;
203 call->resend_at = j;
204 call->ping_at = j;
205 call->expect_rx_by = j;
206 call->expect_req_by = j;
207 call->expect_term_by = j;
208 call->timer.expires = now;
209}
210
211/*
212 * Set up a call for the given parameters.
213 * - Called with the socket lock held, which it must release.
214 * - If it returns a call, the call's lock will need releasing by the caller.
215 */
216struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
217 struct rxrpc_conn_parameters *cp,
218 struct sockaddr_rxrpc *srx,
219 struct rxrpc_call_params *p,
220 gfp_t gfp,
221 unsigned int debug_id)
222 __releases(&rx->sk.sk_lock.slock)
223 __acquires(&call->user_mutex)
224{
225 struct rxrpc_call *call, *xcall;
226 struct rxrpc_net *rxnet;
227 struct rb_node *parent, **pp;
228 const void *here = __builtin_return_address(0);
229 int ret;
230
231 _enter("%p,%lx", rx, p->user_call_ID);
232
233 call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
234 if (IS_ERR(call)) {
235 release_sock(&rx->sk);
236 _leave(" = %ld", PTR_ERR(call));
237 return call;
238 }
239
240 if (p->intr)
241 __set_bit(RXRPC_CALL_IS_INTR, &call->flags);
242 call->tx_total_len = p->tx_total_len;
243 trace_rxrpc_call(call->debug_id, rxrpc_call_new_client,
244 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(rx, call, cp, srx, gfp);
291 if (ret < 0)
292 goto error;
293
294 trace_rxrpc_call(call->debug_id, rxrpc_call_connected,
295 atomic_read(&call->usage), 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->debug_id, rxrpc_call_error,
318 atomic_read(&call->usage), 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 * Set up an incoming call. call->conn points to the connection.
328 * This is called in BH context and isn't allowed to fail.
329 */
330void rxrpc_incoming_call(struct rxrpc_sock *rx,
331 struct rxrpc_call *call,
332 struct sk_buff *skb)
333{
334 struct rxrpc_connection *conn = call->conn;
335 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
336 u32 chan;
337
338 _enter(",%d", call->conn->debug_id);
339
340 rcu_assign_pointer(call->socket, rx);
341 call->call_id = sp->hdr.callNumber;
342 call->service_id = sp->hdr.serviceId;
343 call->cid = sp->hdr.cid;
344 call->state = RXRPC_CALL_SERVER_ACCEPTING;
345 if (sp->hdr.securityIndex > 0)
346 call->state = RXRPC_CALL_SERVER_SECURING;
347 call->cong_tstamp = skb->tstamp;
348
349 /* Set the channel for this call. We don't get channel_lock as we're
350 * only defending against the data_ready handler (which we're called
351 * from) and the RESPONSE packet parser (which is only really
352 * interested in call_counter and can cope with a disagreement with the
353 * call pointer).
354 */
355 chan = sp->hdr.cid & RXRPC_CHANNELMASK;
356 conn->channels[chan].call_counter = call->call_id;
357 conn->channels[chan].call_id = call->call_id;
358 rcu_assign_pointer(conn->channels[chan].call, call);
359
360 spin_lock(&conn->params.peer->lock);
361 hlist_add_head_rcu(&call->error_link, &conn->params.peer->error_targets);
362 spin_unlock(&conn->params.peer->lock);
363
364 _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
365
366 rxrpc_start_call_timer(call);
367 _leave("");
368}
369
370/*
371 * Queue a call's work processor, getting a ref to pass to the work queue.
372 */
373bool rxrpc_queue_call(struct rxrpc_call *call)
374{
375 const void *here = __builtin_return_address(0);
376 int n = atomic_fetch_add_unless(&call->usage, 1, 0);
377 if (n == 0)
378 return false;
379 if (rxrpc_queue_work(&call->processor))
380 trace_rxrpc_call(call->debug_id, rxrpc_call_queued, n + 1,
381 here, NULL);
382 else
383 rxrpc_put_call(call, rxrpc_call_put_noqueue);
384 return true;
385}
386
387/*
388 * Queue a call's work processor, passing the callers ref to the work queue.
389 */
390bool __rxrpc_queue_call(struct rxrpc_call *call)
391{
392 const void *here = __builtin_return_address(0);
393 int n = atomic_read(&call->usage);
394 ASSERTCMP(n, >=, 1);
395 if (rxrpc_queue_work(&call->processor))
396 trace_rxrpc_call(call->debug_id, rxrpc_call_queued_ref, n,
397 here, NULL);
398 else
399 rxrpc_put_call(call, rxrpc_call_put_noqueue);
400 return true;
401}
402
403/*
404 * Note the re-emergence of a call.
405 */
406void rxrpc_see_call(struct rxrpc_call *call)
407{
408 const void *here = __builtin_return_address(0);
409 if (call) {
410 int n = atomic_read(&call->usage);
411
412 trace_rxrpc_call(call->debug_id, rxrpc_call_seen, n,
413 here, NULL);
414 }
415}
416
417/*
418 * Note the addition of a ref on a call.
419 */
420void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
421{
422 const void *here = __builtin_return_address(0);
423 int n = atomic_inc_return(&call->usage);
424
425 trace_rxrpc_call(call->debug_id, op, n, here, NULL);
426}
427
428/*
429 * Clean up the RxTx skb ring.
430 */
431static void rxrpc_cleanup_ring(struct rxrpc_call *call)
432{
433 int i;
434
435 for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
436 rxrpc_free_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
437 call->rxtx_buffer[i] = NULL;
438 }
439}
440
441/*
442 * Detach a call from its owning socket.
443 */
444void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
445{
446 const void *here = __builtin_return_address(0);
447 struct rxrpc_connection *conn = call->conn;
448 bool put = false;
449
450 _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
451
452 trace_rxrpc_call(call->debug_id, rxrpc_call_release,
453 atomic_read(&call->usage),
454 here, (const void *)call->flags);
455
456 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
457
458 spin_lock_bh(&call->lock);
459 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
460 BUG();
461 spin_unlock_bh(&call->lock);
462
463 del_timer_sync(&call->timer);
464
465 /* Make sure we don't get any more notifications */
466 write_lock_bh(&rx->recvmsg_lock);
467
468 if (!list_empty(&call->recvmsg_link)) {
469 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
470 call, call->events, call->flags);
471 list_del(&call->recvmsg_link);
472 put = true;
473 }
474
475 /* list_empty() must return false in rxrpc_notify_socket() */
476 call->recvmsg_link.next = NULL;
477 call->recvmsg_link.prev = NULL;
478
479 write_unlock_bh(&rx->recvmsg_lock);
480 if (put)
481 rxrpc_put_call(call, rxrpc_call_put);
482
483 write_lock(&rx->call_lock);
484
485 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
486 rb_erase(&call->sock_node, &rx->calls);
487 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
488 rxrpc_put_call(call, rxrpc_call_put_userid);
489 }
490
491 list_del(&call->sock_link);
492 write_unlock(&rx->call_lock);
493
494 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
495
496 if (conn)
497 rxrpc_disconnect_call(call);
498 if (call->security)
499 call->security->free_call_crypto(call);
500
501 rxrpc_cleanup_ring(call);
502 _leave("");
503}
504
505/*
506 * release all the calls associated with a socket
507 */
508void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
509{
510 struct rxrpc_call *call;
511
512 _enter("%p", rx);
513
514 while (!list_empty(&rx->to_be_accepted)) {
515 call = list_entry(rx->to_be_accepted.next,
516 struct rxrpc_call, accept_link);
517 list_del(&call->accept_link);
518 rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
519 rxrpc_put_call(call, rxrpc_call_put);
520 }
521
522 while (!list_empty(&rx->sock_calls)) {
523 call = list_entry(rx->sock_calls.next,
524 struct rxrpc_call, sock_link);
525 rxrpc_get_call(call, rxrpc_call_got);
526 rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
527 rxrpc_send_abort_packet(call);
528 rxrpc_release_call(rx, call);
529 rxrpc_put_call(call, rxrpc_call_put);
530 }
531
532 _leave("");
533}
534
535/*
536 * release a call
537 */
538void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
539{
540 struct rxrpc_net *rxnet = call->rxnet;
541 const void *here = __builtin_return_address(0);
542 unsigned int debug_id = call->debug_id;
543 int n;
544
545 ASSERT(call != NULL);
546
547 n = atomic_dec_return(&call->usage);
548 trace_rxrpc_call(debug_id, op, n, here, NULL);
549 ASSERTCMP(n, >=, 0);
550 if (n == 0) {
551 _debug("call %d dead", call->debug_id);
552 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
553
554 if (!list_empty(&call->link)) {
555 write_lock(&rxnet->call_lock);
556 list_del_init(&call->link);
557 write_unlock(&rxnet->call_lock);
558 }
559
560 rxrpc_cleanup_call(call);
561 }
562}
563
564/*
565 * Final call destruction under RCU.
566 */
567static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
568{
569 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
570 struct rxrpc_net *rxnet = call->rxnet;
571
572 rxrpc_put_peer(call->peer);
573 kfree(call->rxtx_buffer);
574 kfree(call->rxtx_annotations);
575 kmem_cache_free(rxrpc_call_jar, call);
576 if (atomic_dec_and_test(&rxnet->nr_calls))
577 wake_up_var(&rxnet->nr_calls);
578}
579
580/*
581 * clean up a call
582 */
583void rxrpc_cleanup_call(struct rxrpc_call *call)
584{
585 _net("DESTROY CALL %d", call->debug_id);
586
587 memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
588
589 del_timer_sync(&call->timer);
590
591 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
592 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
593 ASSERTCMP(call->conn, ==, NULL);
594
595 rxrpc_cleanup_ring(call);
596 rxrpc_free_skb(call->tx_pending, rxrpc_skb_cleaned);
597
598 call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
599}
600
601/*
602 * Make sure that all calls are gone from a network namespace. To reach this
603 * point, any open UDP sockets in that namespace must have been closed, so any
604 * outstanding calls cannot be doing I/O.
605 */
606void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
607{
608 struct rxrpc_call *call;
609
610 _enter("");
611
612 if (!list_empty(&rxnet->calls)) {
613 write_lock(&rxnet->call_lock);
614
615 while (!list_empty(&rxnet->calls)) {
616 call = list_entry(rxnet->calls.next,
617 struct rxrpc_call, link);
618 _debug("Zapping call %p", call);
619
620 rxrpc_see_call(call);
621 list_del_init(&call->link);
622
623 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
624 call, atomic_read(&call->usage),
625 rxrpc_call_states[call->state],
626 call->flags, call->events);
627
628 write_unlock(&rxnet->call_lock);
629 cond_resched();
630 write_lock(&rxnet->call_lock);
631 }
632
633 write_unlock(&rxnet->call_lock);
634 }
635
636 atomic_dec(&rxnet->nr_calls);
637 wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
638}
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}