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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_RECV_REQUEST] = "SvRcvReq",
27 [RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq",
28 [RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl",
29 [RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK",
30 [RXRPC_CALL_COMPLETE] = "Complete",
31};
32
33const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
34 [RXRPC_CALL_SUCCEEDED] = "Complete",
35 [RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
36 [RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
37 [RXRPC_CALL_LOCAL_ERROR] = "LocError",
38 [RXRPC_CALL_NETWORK_ERROR] = "NetError",
39};
40
41struct kmem_cache *rxrpc_call_jar;
42
43static void rxrpc_call_timer_expired(struct timer_list *t)
44{
45 struct rxrpc_call *call = from_timer(call, t, timer);
46
47 _enter("%d", call->debug_id);
48
49 if (call->state < RXRPC_CALL_COMPLETE) {
50 trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
51 rxrpc_queue_call(call);
52 }
53}
54
55static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
56
57/*
58 * find an extant server call
59 * - called in process context with IRQs enabled
60 */
61struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
62 unsigned long user_call_ID)
63{
64 struct rxrpc_call *call;
65 struct rb_node *p;
66
67 _enter("%p,%lx", rx, user_call_ID);
68
69 read_lock(&rx->call_lock);
70
71 p = rx->calls.rb_node;
72 while (p) {
73 call = rb_entry(p, struct rxrpc_call, sock_node);
74
75 if (user_call_ID < call->user_call_ID)
76 p = p->rb_left;
77 else if (user_call_ID > call->user_call_ID)
78 p = p->rb_right;
79 else
80 goto found_extant_call;
81 }
82
83 read_unlock(&rx->call_lock);
84 _leave(" = NULL");
85 return NULL;
86
87found_extant_call:
88 rxrpc_get_call(call, rxrpc_call_got);
89 read_unlock(&rx->call_lock);
90 _leave(" = %p [%d]", call, atomic_read(&call->usage));
91 return call;
92}
93
94/*
95 * allocate a new call
96 */
97struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
98 unsigned int debug_id)
99{
100 struct rxrpc_call *call;
101 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
102
103 call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
104 if (!call)
105 return NULL;
106
107 call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
108 sizeof(struct sk_buff *),
109 gfp);
110 if (!call->rxtx_buffer)
111 goto nomem;
112
113 call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
114 if (!call->rxtx_annotations)
115 goto nomem_2;
116
117 mutex_init(&call->user_mutex);
118
119 /* Prevent lockdep reporting a deadlock false positive between the afs
120 * filesystem and sys_sendmsg() via the mmap sem.
121 */
122 if (rx->sk.sk_kern_sock)
123 lockdep_set_class(&call->user_mutex,
124 &rxrpc_call_user_mutex_lock_class_key);
125
126 timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
127 INIT_WORK(&call->processor, &rxrpc_process_call);
128 INIT_LIST_HEAD(&call->link);
129 INIT_LIST_HEAD(&call->chan_wait_link);
130 INIT_LIST_HEAD(&call->accept_link);
131 INIT_LIST_HEAD(&call->recvmsg_link);
132 INIT_LIST_HEAD(&call->sock_link);
133 init_waitqueue_head(&call->waitq);
134 spin_lock_init(&call->lock);
135 spin_lock_init(&call->notify_lock);
136 spin_lock_init(&call->input_lock);
137 rwlock_init(&call->state_lock);
138 atomic_set(&call->usage, 1);
139 call->debug_id = debug_id;
140 call->tx_total_len = -1;
141 call->next_rx_timo = 20 * HZ;
142 call->next_req_timo = 1 * HZ;
143
144 memset(&call->sock_node, 0xed, sizeof(call->sock_node));
145
146 /* Leave space in the ring to handle a maxed-out jumbo packet */
147 call->rx_winsize = rxrpc_rx_window_size;
148 call->tx_winsize = 16;
149 call->rx_expect_next = 1;
150
151 call->cong_cwnd = 2;
152 call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
153
154 call->rxnet = rxnet;
155 call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
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 call->interruptibility = p->interruptibility;
241 call->tx_total_len = p->tx_total_len;
242 trace_rxrpc_call(call->debug_id, rxrpc_call_new_client,
243 atomic_read(&call->usage),
244 here, (const void *)p->user_call_ID);
245
246 /* We need to protect a partially set up call against the user as we
247 * will be acting outside the socket lock.
248 */
249 mutex_lock(&call->user_mutex);
250
251 /* Publish the call, even though it is incompletely set up as yet */
252 write_lock(&rx->call_lock);
253
254 pp = &rx->calls.rb_node;
255 parent = NULL;
256 while (*pp) {
257 parent = *pp;
258 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
259
260 if (p->user_call_ID < xcall->user_call_ID)
261 pp = &(*pp)->rb_left;
262 else if (p->user_call_ID > xcall->user_call_ID)
263 pp = &(*pp)->rb_right;
264 else
265 goto error_dup_user_ID;
266 }
267
268 rcu_assign_pointer(call->socket, rx);
269 call->user_call_ID = p->user_call_ID;
270 __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
271 rxrpc_get_call(call, rxrpc_call_got_userid);
272 rb_link_node(&call->sock_node, parent, pp);
273 rb_insert_color(&call->sock_node, &rx->calls);
274 list_add(&call->sock_link, &rx->sock_calls);
275
276 write_unlock(&rx->call_lock);
277
278 rxnet = call->rxnet;
279 write_lock(&rxnet->call_lock);
280 list_add_tail(&call->link, &rxnet->calls);
281 write_unlock(&rxnet->call_lock);
282
283 /* From this point on, the call is protected by its own lock. */
284 release_sock(&rx->sk);
285
286 /* Set up or get a connection record and set the protocol parameters,
287 * including channel number and call ID.
288 */
289 ret = rxrpc_connect_call(rx, call, cp, srx, gfp);
290 if (ret < 0)
291 goto error_attached_to_socket;
292
293 trace_rxrpc_call(call->debug_id, rxrpc_call_connected,
294 atomic_read(&call->usage), here, NULL);
295
296 rxrpc_start_call_timer(call);
297
298 _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
299
300 _leave(" = %p [new]", call);
301 return call;
302
303 /* We unexpectedly found the user ID in the list after taking
304 * the call_lock. This shouldn't happen unless the user races
305 * with itself and tries to add the same user ID twice at the
306 * same time in different threads.
307 */
308error_dup_user_ID:
309 write_unlock(&rx->call_lock);
310 release_sock(&rx->sk);
311 __rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
312 RX_CALL_DEAD, -EEXIST);
313 trace_rxrpc_call(call->debug_id, rxrpc_call_error,
314 atomic_read(&call->usage), here, ERR_PTR(-EEXIST));
315 rxrpc_release_call(rx, call);
316 mutex_unlock(&call->user_mutex);
317 rxrpc_put_call(call, rxrpc_call_put);
318 _leave(" = -EEXIST");
319 return ERR_PTR(-EEXIST);
320
321 /* We got an error, but the call is attached to the socket and is in
322 * need of release. However, we might now race with recvmsg() when
323 * completing the call queues it. Return 0 from sys_sendmsg() and
324 * leave the error to recvmsg() to deal with.
325 */
326error_attached_to_socket:
327 trace_rxrpc_call(call->debug_id, rxrpc_call_error,
328 atomic_read(&call->usage), here, ERR_PTR(ret));
329 set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
330 __rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
331 RX_CALL_DEAD, ret);
332 _leave(" = c=%08x [err]", call->debug_id);
333 return call;
334}
335
336/*
337 * Set up an incoming call. call->conn points to the connection.
338 * This is called in BH context and isn't allowed to fail.
339 */
340void rxrpc_incoming_call(struct rxrpc_sock *rx,
341 struct rxrpc_call *call,
342 struct sk_buff *skb)
343{
344 struct rxrpc_connection *conn = call->conn;
345 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
346 u32 chan;
347
348 _enter(",%d", call->conn->debug_id);
349
350 rcu_assign_pointer(call->socket, rx);
351 call->call_id = sp->hdr.callNumber;
352 call->service_id = sp->hdr.serviceId;
353 call->cid = sp->hdr.cid;
354 call->state = RXRPC_CALL_SERVER_SECURING;
355 call->cong_tstamp = skb->tstamp;
356
357 /* Set the channel for this call. We don't get channel_lock as we're
358 * only defending against the data_ready handler (which we're called
359 * from) and the RESPONSE packet parser (which is only really
360 * interested in call_counter and can cope with a disagreement with the
361 * call pointer).
362 */
363 chan = sp->hdr.cid & RXRPC_CHANNELMASK;
364 conn->channels[chan].call_counter = call->call_id;
365 conn->channels[chan].call_id = call->call_id;
366 rcu_assign_pointer(conn->channels[chan].call, call);
367
368 spin_lock(&conn->params.peer->lock);
369 hlist_add_head_rcu(&call->error_link, &conn->params.peer->error_targets);
370 spin_unlock(&conn->params.peer->lock);
371
372 _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
373
374 rxrpc_start_call_timer(call);
375 _leave("");
376}
377
378/*
379 * Queue a call's work processor, getting a ref to pass to the work queue.
380 */
381bool rxrpc_queue_call(struct rxrpc_call *call)
382{
383 const void *here = __builtin_return_address(0);
384 int n = atomic_fetch_add_unless(&call->usage, 1, 0);
385 if (n == 0)
386 return false;
387 if (rxrpc_queue_work(&call->processor))
388 trace_rxrpc_call(call->debug_id, rxrpc_call_queued, n + 1,
389 here, NULL);
390 else
391 rxrpc_put_call(call, rxrpc_call_put_noqueue);
392 return true;
393}
394
395/*
396 * Queue a call's work processor, passing the callers ref to the work queue.
397 */
398bool __rxrpc_queue_call(struct rxrpc_call *call)
399{
400 const void *here = __builtin_return_address(0);
401 int n = atomic_read(&call->usage);
402 ASSERTCMP(n, >=, 1);
403 if (rxrpc_queue_work(&call->processor))
404 trace_rxrpc_call(call->debug_id, rxrpc_call_queued_ref, n,
405 here, NULL);
406 else
407 rxrpc_put_call(call, rxrpc_call_put_noqueue);
408 return true;
409}
410
411/*
412 * Note the re-emergence of a call.
413 */
414void rxrpc_see_call(struct rxrpc_call *call)
415{
416 const void *here = __builtin_return_address(0);
417 if (call) {
418 int n = atomic_read(&call->usage);
419
420 trace_rxrpc_call(call->debug_id, rxrpc_call_seen, n,
421 here, NULL);
422 }
423}
424
425/*
426 * Note the addition of a ref on a call.
427 */
428void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
429{
430 const void *here = __builtin_return_address(0);
431 int n = atomic_inc_return(&call->usage);
432
433 trace_rxrpc_call(call->debug_id, op, n, here, NULL);
434}
435
436/*
437 * Clean up the RxTx skb ring.
438 */
439static void rxrpc_cleanup_ring(struct rxrpc_call *call)
440{
441 int i;
442
443 for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
444 rxrpc_free_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
445 call->rxtx_buffer[i] = NULL;
446 }
447}
448
449/*
450 * Detach a call from its owning socket.
451 */
452void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
453{
454 const void *here = __builtin_return_address(0);
455 struct rxrpc_connection *conn = call->conn;
456 bool put = false;
457
458 _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
459
460 trace_rxrpc_call(call->debug_id, rxrpc_call_release,
461 atomic_read(&call->usage),
462 here, (const void *)call->flags);
463
464 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
465
466 spin_lock_bh(&call->lock);
467 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
468 BUG();
469 spin_unlock_bh(&call->lock);
470
471 del_timer_sync(&call->timer);
472
473 /* Make sure we don't get any more notifications */
474 write_lock_bh(&rx->recvmsg_lock);
475
476 if (!list_empty(&call->recvmsg_link)) {
477 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
478 call, call->events, call->flags);
479 list_del(&call->recvmsg_link);
480 put = true;
481 }
482
483 /* list_empty() must return false in rxrpc_notify_socket() */
484 call->recvmsg_link.next = NULL;
485 call->recvmsg_link.prev = NULL;
486
487 write_unlock_bh(&rx->recvmsg_lock);
488 if (put)
489 rxrpc_put_call(call, rxrpc_call_put);
490
491 write_lock(&rx->call_lock);
492
493 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
494 rb_erase(&call->sock_node, &rx->calls);
495 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
496 rxrpc_put_call(call, rxrpc_call_put_userid);
497 }
498
499 list_del(&call->sock_link);
500 write_unlock(&rx->call_lock);
501
502 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
503
504 if (conn && !test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
505 rxrpc_disconnect_call(call);
506 if (call->security)
507 call->security->free_call_crypto(call);
508
509 rxrpc_cleanup_ring(call);
510 _leave("");
511}
512
513/*
514 * release all the calls associated with a socket
515 */
516void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
517{
518 struct rxrpc_call *call;
519
520 _enter("%p", rx);
521
522 while (!list_empty(&rx->to_be_accepted)) {
523 call = list_entry(rx->to_be_accepted.next,
524 struct rxrpc_call, accept_link);
525 list_del(&call->accept_link);
526 rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
527 rxrpc_put_call(call, rxrpc_call_put);
528 }
529
530 while (!list_empty(&rx->sock_calls)) {
531 call = list_entry(rx->sock_calls.next,
532 struct rxrpc_call, sock_link);
533 rxrpc_get_call(call, rxrpc_call_got);
534 rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
535 rxrpc_send_abort_packet(call);
536 rxrpc_release_call(rx, call);
537 rxrpc_put_call(call, rxrpc_call_put);
538 }
539
540 _leave("");
541}
542
543/*
544 * release a call
545 */
546void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
547{
548 struct rxrpc_net *rxnet = call->rxnet;
549 const void *here = __builtin_return_address(0);
550 unsigned int debug_id = call->debug_id;
551 int n;
552
553 ASSERT(call != NULL);
554
555 n = atomic_dec_return(&call->usage);
556 trace_rxrpc_call(debug_id, op, n, here, NULL);
557 ASSERTCMP(n, >=, 0);
558 if (n == 0) {
559 _debug("call %d dead", call->debug_id);
560 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
561
562 if (!list_empty(&call->link)) {
563 write_lock(&rxnet->call_lock);
564 list_del_init(&call->link);
565 write_unlock(&rxnet->call_lock);
566 }
567
568 rxrpc_cleanup_call(call);
569 }
570}
571
572/*
573 * Final call destruction - but must be done in process context.
574 */
575static void rxrpc_destroy_call(struct work_struct *work)
576{
577 struct rxrpc_call *call = container_of(work, struct rxrpc_call, processor);
578 struct rxrpc_net *rxnet = call->rxnet;
579
580 rxrpc_put_connection(call->conn);
581 rxrpc_put_peer(call->peer);
582 kfree(call->rxtx_buffer);
583 kfree(call->rxtx_annotations);
584 kmem_cache_free(rxrpc_call_jar, call);
585 if (atomic_dec_and_test(&rxnet->nr_calls))
586 wake_up_var(&rxnet->nr_calls);
587}
588
589/*
590 * Final call destruction under RCU.
591 */
592static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
593{
594 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
595
596 if (in_softirq()) {
597 INIT_WORK(&call->processor, rxrpc_destroy_call);
598 if (!rxrpc_queue_work(&call->processor))
599 BUG();
600 } else {
601 rxrpc_destroy_call(&call->processor);
602 }
603}
604
605/*
606 * clean up a call
607 */
608void rxrpc_cleanup_call(struct rxrpc_call *call)
609{
610 _net("DESTROY CALL %d", call->debug_id);
611
612 memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
613
614 del_timer_sync(&call->timer);
615
616 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
617 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
618
619 rxrpc_cleanup_ring(call);
620 rxrpc_free_skb(call->tx_pending, rxrpc_skb_cleaned);
621
622 call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
623}
624
625/*
626 * Make sure that all calls are gone from a network namespace. To reach this
627 * point, any open UDP sockets in that namespace must have been closed, so any
628 * outstanding calls cannot be doing I/O.
629 */
630void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
631{
632 struct rxrpc_call *call;
633
634 _enter("");
635
636 if (!list_empty(&rxnet->calls)) {
637 write_lock(&rxnet->call_lock);
638
639 while (!list_empty(&rxnet->calls)) {
640 call = list_entry(rxnet->calls.next,
641 struct rxrpc_call, link);
642 _debug("Zapping call %p", call);
643
644 rxrpc_see_call(call);
645 list_del_init(&call->link);
646
647 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
648 call, atomic_read(&call->usage),
649 rxrpc_call_states[call->state],
650 call->flags, call->events);
651
652 write_unlock(&rxnet->call_lock);
653 cond_resched();
654 write_lock(&rxnet->call_lock);
655 }
656
657 write_unlock(&rxnet->call_lock);
658 }
659
660 atomic_dec(&rxnet->nr_calls);
661 wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
662}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* RxRPC individual remote procedure call handling
3 *
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/slab.h>
11#include <linux/module.h>
12#include <linux/circ_buf.h>
13#include <linux/spinlock_types.h>
14#include <net/sock.h>
15#include <net/af_rxrpc.h>
16#include "ar-internal.h"
17
18const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
19 [RXRPC_CALL_UNINITIALISED] = "Uninit ",
20 [RXRPC_CALL_CLIENT_AWAIT_CONN] = "ClWtConn",
21 [RXRPC_CALL_CLIENT_SEND_REQUEST] = "ClSndReq",
22 [RXRPC_CALL_CLIENT_AWAIT_REPLY] = "ClAwtRpl",
23 [RXRPC_CALL_CLIENT_RECV_REPLY] = "ClRcvRpl",
24 [RXRPC_CALL_SERVER_PREALLOC] = "SvPrealc",
25 [RXRPC_CALL_SERVER_SECURING] = "SvSecure",
26 [RXRPC_CALL_SERVER_RECV_REQUEST] = "SvRcvReq",
27 [RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq",
28 [RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl",
29 [RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK",
30 [RXRPC_CALL_COMPLETE] = "Complete",
31};
32
33const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
34 [RXRPC_CALL_SUCCEEDED] = "Complete",
35 [RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
36 [RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
37 [RXRPC_CALL_LOCAL_ERROR] = "LocError",
38 [RXRPC_CALL_NETWORK_ERROR] = "NetError",
39};
40
41struct kmem_cache *rxrpc_call_jar;
42
43static DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000);
44static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000);
45
46void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
47{
48 struct rxrpc_local *local = call->local;
49 bool busy;
50
51 if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
52 spin_lock_bh(&local->lock);
53 busy = !list_empty(&call->attend_link);
54 trace_rxrpc_poke_call(call, busy, what);
55 if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
56 busy = true;
57 if (!busy) {
58 list_add_tail(&call->attend_link, &local->call_attend_q);
59 }
60 spin_unlock_bh(&local->lock);
61 if (!busy)
62 rxrpc_wake_up_io_thread(local);
63 }
64}
65
66static void rxrpc_call_timer_expired(struct timer_list *t)
67{
68 struct rxrpc_call *call = from_timer(call, t, timer);
69
70 _enter("%d", call->debug_id);
71
72 if (!__rxrpc_call_is_complete(call)) {
73 trace_rxrpc_timer_expired(call, jiffies);
74 rxrpc_poke_call(call, rxrpc_call_poke_timer);
75 }
76}
77
78void rxrpc_reduce_call_timer(struct rxrpc_call *call,
79 unsigned long expire_at,
80 unsigned long now,
81 enum rxrpc_timer_trace why)
82{
83 trace_rxrpc_timer(call, why, now);
84 timer_reduce(&call->timer, expire_at);
85}
86
87static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
88
89static void rxrpc_destroy_call(struct work_struct *);
90
91/*
92 * find an extant server call
93 * - called in process context with IRQs enabled
94 */
95struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
96 unsigned long user_call_ID)
97{
98 struct rxrpc_call *call;
99 struct rb_node *p;
100
101 _enter("%p,%lx", rx, user_call_ID);
102
103 read_lock(&rx->call_lock);
104
105 p = rx->calls.rb_node;
106 while (p) {
107 call = rb_entry(p, struct rxrpc_call, sock_node);
108
109 if (user_call_ID < call->user_call_ID)
110 p = p->rb_left;
111 else if (user_call_ID > call->user_call_ID)
112 p = p->rb_right;
113 else
114 goto found_extant_call;
115 }
116
117 read_unlock(&rx->call_lock);
118 _leave(" = NULL");
119 return NULL;
120
121found_extant_call:
122 rxrpc_get_call(call, rxrpc_call_get_sendmsg);
123 read_unlock(&rx->call_lock);
124 _leave(" = %p [%d]", call, refcount_read(&call->ref));
125 return call;
126}
127
128/*
129 * allocate a new call
130 */
131struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
132 unsigned int debug_id)
133{
134 struct rxrpc_call *call;
135 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
136
137 call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
138 if (!call)
139 return NULL;
140
141 mutex_init(&call->user_mutex);
142
143 /* Prevent lockdep reporting a deadlock false positive between the afs
144 * filesystem and sys_sendmsg() via the mmap sem.
145 */
146 if (rx->sk.sk_kern_sock)
147 lockdep_set_class(&call->user_mutex,
148 &rxrpc_call_user_mutex_lock_class_key);
149
150 timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
151 INIT_WORK(&call->destroyer, rxrpc_destroy_call);
152 INIT_LIST_HEAD(&call->link);
153 INIT_LIST_HEAD(&call->wait_link);
154 INIT_LIST_HEAD(&call->accept_link);
155 INIT_LIST_HEAD(&call->recvmsg_link);
156 INIT_LIST_HEAD(&call->sock_link);
157 INIT_LIST_HEAD(&call->attend_link);
158 INIT_LIST_HEAD(&call->tx_sendmsg);
159 INIT_LIST_HEAD(&call->tx_buffer);
160 skb_queue_head_init(&call->recvmsg_queue);
161 skb_queue_head_init(&call->rx_oos_queue);
162 init_waitqueue_head(&call->waitq);
163 spin_lock_init(&call->notify_lock);
164 spin_lock_init(&call->tx_lock);
165 refcount_set(&call->ref, 1);
166 call->debug_id = debug_id;
167 call->tx_total_len = -1;
168 call->next_rx_timo = 20 * HZ;
169 call->next_req_timo = 1 * HZ;
170 call->ackr_window = 1;
171 call->ackr_wtop = 1;
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 */
195static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
196 struct rxrpc_conn_parameters *cp,
197 struct rxrpc_call_params *p,
198 gfp_t gfp,
199 unsigned int debug_id)
200{
201 struct rxrpc_call *call;
202 ktime_t now;
203 int ret;
204
205 _enter("");
206
207 call = rxrpc_alloc_call(rx, gfp, debug_id);
208 if (!call)
209 return ERR_PTR(-ENOMEM);
210 now = ktime_get_real();
211 call->acks_latest_ts = now;
212 call->cong_tstamp = now;
213 call->dest_srx = cp->peer->srx;
214 call->dest_srx.srx_service = cp->service_id;
215 call->interruptibility = p->interruptibility;
216 call->tx_total_len = p->tx_total_len;
217 call->key = key_get(cp->key);
218 call->peer = rxrpc_get_peer(cp->peer, rxrpc_peer_get_call);
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 if (p->timeouts.normal)
229 call->next_rx_timo = min(msecs_to_jiffies(p->timeouts.normal), 1UL);
230 if (p->timeouts.idle)
231 call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL);
232 if (p->timeouts.hard)
233 call->hard_timo = p->timeouts.hard * HZ;
234
235 ret = rxrpc_init_client_call_security(call);
236 if (ret < 0) {
237 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
238 rxrpc_put_call(call, rxrpc_call_put_discard_error);
239 return ERR_PTR(ret);
240 }
241
242 rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
243
244 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
245 p->user_call_ID, rxrpc_call_new_client);
246
247 _leave(" = %p", call);
248 return call;
249}
250
251/*
252 * Initiate the call ack/resend/expiry timer.
253 */
254void rxrpc_start_call_timer(struct rxrpc_call *call)
255{
256 unsigned long now = jiffies;
257 unsigned long j = now + MAX_JIFFY_OFFSET;
258
259 call->delay_ack_at = j;
260 call->ack_lost_at = j;
261 call->resend_at = j;
262 call->ping_at = j;
263 call->keepalive_at = j;
264 call->expect_rx_by = j;
265 call->expect_req_by = j;
266 call->expect_term_by = j + call->hard_timo;
267 call->timer.expires = now;
268}
269
270/*
271 * Wait for a call slot to become available.
272 */
273static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
274{
275 struct semaphore *limiter = &rxrpc_call_limiter;
276
277 if (p->kernel)
278 limiter = &rxrpc_kernel_call_limiter;
279 if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
280 down(limiter);
281 return limiter;
282 }
283 return down_interruptible(limiter) < 0 ? NULL : limiter;
284}
285
286/*
287 * Release a call slot.
288 */
289static void rxrpc_put_call_slot(struct rxrpc_call *call)
290{
291 struct semaphore *limiter = &rxrpc_call_limiter;
292
293 if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
294 limiter = &rxrpc_kernel_call_limiter;
295 up(limiter);
296}
297
298/*
299 * Start the process of connecting a call. We obtain a peer and a connection
300 * bundle, but the actual association of a call with a connection is offloaded
301 * to the I/O thread to simplify locking.
302 */
303static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
304{
305 struct rxrpc_local *local = call->local;
306 int ret = -ENOMEM;
307
308 _enter("{%d,%lx},", call->debug_id, call->user_call_ID);
309
310 ret = rxrpc_look_up_bundle(call, gfp);
311 if (ret < 0)
312 goto error;
313
314 trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
315 rxrpc_get_call(call, rxrpc_call_get_io_thread);
316 spin_lock(&local->client_call_lock);
317 list_add_tail(&call->wait_link, &local->new_client_calls);
318 spin_unlock(&local->client_call_lock);
319 rxrpc_wake_up_io_thread(local);
320 return 0;
321
322error:
323 __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
324 return ret;
325}
326
327/*
328 * Set up a call for the given parameters.
329 * - Called with the socket lock held, which it must release.
330 * - If it returns a call, the call's lock will need releasing by the caller.
331 */
332struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
333 struct rxrpc_conn_parameters *cp,
334 struct rxrpc_call_params *p,
335 gfp_t gfp,
336 unsigned int debug_id)
337 __releases(&rx->sk.sk_lock.slock)
338 __acquires(&call->user_mutex)
339{
340 struct rxrpc_call *call, *xcall;
341 struct rxrpc_net *rxnet;
342 struct semaphore *limiter;
343 struct rb_node *parent, **pp;
344 int ret;
345
346 _enter("%p,%lx", rx, p->user_call_ID);
347
348 if (WARN_ON_ONCE(!cp->peer)) {
349 release_sock(&rx->sk);
350 return ERR_PTR(-EIO);
351 }
352
353 limiter = rxrpc_get_call_slot(p, gfp);
354 if (!limiter) {
355 release_sock(&rx->sk);
356 return ERR_PTR(-ERESTARTSYS);
357 }
358
359 call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id);
360 if (IS_ERR(call)) {
361 release_sock(&rx->sk);
362 up(limiter);
363 _leave(" = %ld", PTR_ERR(call));
364 return call;
365 }
366
367 /* We need to protect a partially set up call against the user as we
368 * will be acting outside the socket lock.
369 */
370 mutex_lock(&call->user_mutex);
371
372 /* Publish the call, even though it is incompletely set up as yet */
373 write_lock(&rx->call_lock);
374
375 pp = &rx->calls.rb_node;
376 parent = NULL;
377 while (*pp) {
378 parent = *pp;
379 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
380
381 if (p->user_call_ID < xcall->user_call_ID)
382 pp = &(*pp)->rb_left;
383 else if (p->user_call_ID > xcall->user_call_ID)
384 pp = &(*pp)->rb_right;
385 else
386 goto error_dup_user_ID;
387 }
388
389 rcu_assign_pointer(call->socket, rx);
390 call->user_call_ID = p->user_call_ID;
391 __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
392 rxrpc_get_call(call, rxrpc_call_get_userid);
393 rb_link_node(&call->sock_node, parent, pp);
394 rb_insert_color(&call->sock_node, &rx->calls);
395 list_add(&call->sock_link, &rx->sock_calls);
396
397 write_unlock(&rx->call_lock);
398
399 rxnet = call->rxnet;
400 spin_lock(&rxnet->call_lock);
401 list_add_tail_rcu(&call->link, &rxnet->calls);
402 spin_unlock(&rxnet->call_lock);
403
404 /* From this point on, the call is protected by its own lock. */
405 release_sock(&rx->sk);
406
407 /* Set up or get a connection record and set the protocol parameters,
408 * including channel number and call ID.
409 */
410 ret = rxrpc_connect_call(call, gfp);
411 if (ret < 0)
412 goto error_attached_to_socket;
413
414 _leave(" = %p [new]", call);
415 return call;
416
417 /* We unexpectedly found the user ID in the list after taking
418 * the call_lock. This shouldn't happen unless the user races
419 * with itself and tries to add the same user ID twice at the
420 * same time in different threads.
421 */
422error_dup_user_ID:
423 write_unlock(&rx->call_lock);
424 release_sock(&rx->sk);
425 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
426 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
427 rxrpc_call_see_userid_exists);
428 mutex_unlock(&call->user_mutex);
429 rxrpc_put_call(call, rxrpc_call_put_userid_exists);
430 _leave(" = -EEXIST");
431 return ERR_PTR(-EEXIST);
432
433 /* We got an error, but the call is attached to the socket and is in
434 * need of release. However, we might now race with recvmsg() when it
435 * completion notifies the socket. Return 0 from sys_sendmsg() and
436 * leave the error to recvmsg() to deal with.
437 */
438error_attached_to_socket:
439 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
440 rxrpc_call_see_connect_failed);
441 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
442 _leave(" = c=%08x [err]", call->debug_id);
443 return call;
444}
445
446/*
447 * Set up an incoming call. call->conn points to the connection.
448 * This is called in BH context and isn't allowed to fail.
449 */
450void rxrpc_incoming_call(struct rxrpc_sock *rx,
451 struct rxrpc_call *call,
452 struct sk_buff *skb)
453{
454 struct rxrpc_connection *conn = call->conn;
455 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
456 u32 chan;
457
458 _enter(",%d", call->conn->debug_id);
459
460 rcu_assign_pointer(call->socket, rx);
461 call->call_id = sp->hdr.callNumber;
462 call->dest_srx.srx_service = sp->hdr.serviceId;
463 call->cid = sp->hdr.cid;
464 call->cong_tstamp = skb->tstamp;
465
466 __set_bit(RXRPC_CALL_EXPOSED, &call->flags);
467 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
468
469 spin_lock(&conn->state_lock);
470
471 switch (conn->state) {
472 case RXRPC_CONN_SERVICE_UNSECURED:
473 case RXRPC_CONN_SERVICE_CHALLENGING:
474 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
475 break;
476 case RXRPC_CONN_SERVICE:
477 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
478 break;
479
480 case RXRPC_CONN_ABORTED:
481 rxrpc_set_call_completion(call, conn->completion,
482 conn->abort_code, conn->error);
483 break;
484 default:
485 BUG();
486 }
487
488 rxrpc_get_call(call, rxrpc_call_get_io_thread);
489
490 /* Set the channel for this call. We don't get channel_lock as we're
491 * only defending against the data_ready handler (which we're called
492 * from) and the RESPONSE packet parser (which is only really
493 * interested in call_counter and can cope with a disagreement with the
494 * call pointer).
495 */
496 chan = sp->hdr.cid & RXRPC_CHANNELMASK;
497 conn->channels[chan].call_counter = call->call_id;
498 conn->channels[chan].call_id = call->call_id;
499 conn->channels[chan].call = call;
500 spin_unlock(&conn->state_lock);
501
502 spin_lock(&conn->peer->lock);
503 hlist_add_head(&call->error_link, &conn->peer->error_targets);
504 spin_unlock(&conn->peer->lock);
505
506 rxrpc_start_call_timer(call);
507 _leave("");
508}
509
510/*
511 * Note the re-emergence of a call.
512 */
513void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
514{
515 if (call) {
516 int r = refcount_read(&call->ref);
517
518 trace_rxrpc_call(call->debug_id, r, 0, why);
519 }
520}
521
522struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
523 enum rxrpc_call_trace why)
524{
525 int r;
526
527 if (!call || !__refcount_inc_not_zero(&call->ref, &r))
528 return NULL;
529 trace_rxrpc_call(call->debug_id, r + 1, 0, why);
530 return call;
531}
532
533/*
534 * Note the addition of a ref on a call.
535 */
536void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
537{
538 int r;
539
540 __refcount_inc(&call->ref, &r);
541 trace_rxrpc_call(call->debug_id, r + 1, 0, why);
542}
543
544/*
545 * Clean up the Rx skb ring.
546 */
547static void rxrpc_cleanup_ring(struct rxrpc_call *call)
548{
549 rxrpc_purge_queue(&call->recvmsg_queue);
550 rxrpc_purge_queue(&call->rx_oos_queue);
551}
552
553/*
554 * Detach a call from its owning socket.
555 */
556void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
557{
558 struct rxrpc_connection *conn = call->conn;
559 bool put = false, putu = false;
560
561 _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
562
563 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
564 call->flags, rxrpc_call_see_release);
565
566 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
567 BUG();
568
569 rxrpc_put_call_slot(call);
570
571 /* Make sure we don't get any more notifications */
572 spin_lock(&rx->recvmsg_lock);
573
574 if (!list_empty(&call->recvmsg_link)) {
575 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
576 call, call->events, call->flags);
577 list_del(&call->recvmsg_link);
578 put = true;
579 }
580
581 /* list_empty() must return false in rxrpc_notify_socket() */
582 call->recvmsg_link.next = NULL;
583 call->recvmsg_link.prev = NULL;
584
585 spin_unlock(&rx->recvmsg_lock);
586 if (put)
587 rxrpc_put_call(call, rxrpc_call_put_unnotify);
588
589 write_lock(&rx->call_lock);
590
591 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
592 rb_erase(&call->sock_node, &rx->calls);
593 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
594 putu = true;
595 }
596
597 list_del(&call->sock_link);
598 write_unlock(&rx->call_lock);
599
600 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
601
602 if (putu)
603 rxrpc_put_call(call, rxrpc_call_put_userid);
604
605 _leave("");
606}
607
608/*
609 * release all the calls associated with a socket
610 */
611void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
612{
613 struct rxrpc_call *call;
614
615 _enter("%p", rx);
616
617 while (!list_empty(&rx->to_be_accepted)) {
618 call = list_entry(rx->to_be_accepted.next,
619 struct rxrpc_call, accept_link);
620 list_del(&call->accept_link);
621 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
622 rxrpc_abort_call_sock_release_tba);
623 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
624 }
625
626 while (!list_empty(&rx->sock_calls)) {
627 call = list_entry(rx->sock_calls.next,
628 struct rxrpc_call, sock_link);
629 rxrpc_get_call(call, rxrpc_call_get_release_sock);
630 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
631 rxrpc_abort_call_sock_release);
632 rxrpc_release_call(rx, call);
633 rxrpc_put_call(call, rxrpc_call_put_release_sock);
634 }
635
636 _leave("");
637}
638
639/*
640 * release a call
641 */
642void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
643{
644 struct rxrpc_net *rxnet = call->rxnet;
645 unsigned int debug_id = call->debug_id;
646 bool dead;
647 int r;
648
649 ASSERT(call != NULL);
650
651 dead = __refcount_dec_and_test(&call->ref, &r);
652 trace_rxrpc_call(debug_id, r - 1, 0, why);
653 if (dead) {
654 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
655
656 if (!list_empty(&call->link)) {
657 spin_lock(&rxnet->call_lock);
658 list_del_init(&call->link);
659 spin_unlock(&rxnet->call_lock);
660 }
661
662 rxrpc_cleanup_call(call);
663 }
664}
665
666/*
667 * Free up the call under RCU.
668 */
669static void rxrpc_rcu_free_call(struct rcu_head *rcu)
670{
671 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
672 struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
673
674 kmem_cache_free(rxrpc_call_jar, call);
675 if (atomic_dec_and_test(&rxnet->nr_calls))
676 wake_up_var(&rxnet->nr_calls);
677}
678
679/*
680 * Final call destruction - but must be done in process context.
681 */
682static void rxrpc_destroy_call(struct work_struct *work)
683{
684 struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
685 struct rxrpc_txbuf *txb;
686
687 del_timer_sync(&call->timer);
688
689 rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
690 rxrpc_cleanup_ring(call);
691 while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
692 struct rxrpc_txbuf, call_link))) {
693 list_del(&txb->call_link);
694 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
695 }
696 while ((txb = list_first_entry_or_null(&call->tx_buffer,
697 struct rxrpc_txbuf, call_link))) {
698 list_del(&txb->call_link);
699 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
700 }
701
702 rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
703 rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
704 rxrpc_deactivate_bundle(call->bundle);
705 rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
706 rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
707 rxrpc_put_local(call->local, rxrpc_local_put_call);
708 call_rcu(&call->rcu, rxrpc_rcu_free_call);
709}
710
711/*
712 * clean up a call
713 */
714void rxrpc_cleanup_call(struct rxrpc_call *call)
715{
716 memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
717
718 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
719 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
720
721 del_timer(&call->timer);
722
723 if (rcu_read_lock_held())
724 /* Can't use the rxrpc workqueue as we need to cancel/flush
725 * something that may be running/waiting there.
726 */
727 schedule_work(&call->destroyer);
728 else
729 rxrpc_destroy_call(&call->destroyer);
730}
731
732/*
733 * Make sure that all calls are gone from a network namespace. To reach this
734 * point, any open UDP sockets in that namespace must have been closed, so any
735 * outstanding calls cannot be doing I/O.
736 */
737void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
738{
739 struct rxrpc_call *call;
740
741 _enter("");
742
743 if (!list_empty(&rxnet->calls)) {
744 spin_lock(&rxnet->call_lock);
745
746 while (!list_empty(&rxnet->calls)) {
747 call = list_entry(rxnet->calls.next,
748 struct rxrpc_call, link);
749 _debug("Zapping call %p", call);
750
751 rxrpc_see_call(call, rxrpc_call_see_zap);
752 list_del_init(&call->link);
753
754 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
755 call, refcount_read(&call->ref),
756 rxrpc_call_states[__rxrpc_call_state(call)],
757 call->flags, call->events);
758
759 spin_unlock(&rxnet->call_lock);
760 cond_resched();
761 spin_lock(&rxnet->call_lock);
762 }
763
764 spin_unlock(&rxnet->call_lock);
765 }
766
767 atomic_dec(&rxnet->nr_calls);
768 wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
769}