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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);
74 rxrpc_poke_call(call, rxrpc_call_poke_timer);
75 }
76}
77
78static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
79
80static void rxrpc_destroy_call(struct work_struct *);
81
82/*
83 * find an extant server call
84 * - called in process context with IRQs enabled
85 */
86struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
87 unsigned long user_call_ID)
88{
89 struct rxrpc_call *call;
90 struct rb_node *p;
91
92 _enter("%p,%lx", rx, user_call_ID);
93
94 read_lock(&rx->call_lock);
95
96 p = rx->calls.rb_node;
97 while (p) {
98 call = rb_entry(p, struct rxrpc_call, sock_node);
99
100 if (user_call_ID < call->user_call_ID)
101 p = p->rb_left;
102 else if (user_call_ID > call->user_call_ID)
103 p = p->rb_right;
104 else
105 goto found_extant_call;
106 }
107
108 read_unlock(&rx->call_lock);
109 _leave(" = NULL");
110 return NULL;
111
112found_extant_call:
113 rxrpc_get_call(call, rxrpc_call_get_sendmsg);
114 read_unlock(&rx->call_lock);
115 _leave(" = %p [%d]", call, refcount_read(&call->ref));
116 return call;
117}
118
119/*
120 * allocate a new call
121 */
122struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
123 unsigned int debug_id)
124{
125 struct rxrpc_call *call;
126 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
127
128 call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
129 if (!call)
130 return NULL;
131
132 mutex_init(&call->user_mutex);
133
134 /* Prevent lockdep reporting a deadlock false positive between the afs
135 * filesystem and sys_sendmsg() via the mmap sem.
136 */
137 if (rx->sk.sk_kern_sock)
138 lockdep_set_class(&call->user_mutex,
139 &rxrpc_call_user_mutex_lock_class_key);
140
141 timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
142 INIT_WORK(&call->destroyer, rxrpc_destroy_call);
143 INIT_LIST_HEAD(&call->link);
144 INIT_LIST_HEAD(&call->wait_link);
145 INIT_LIST_HEAD(&call->accept_link);
146 INIT_LIST_HEAD(&call->recvmsg_link);
147 INIT_LIST_HEAD(&call->sock_link);
148 INIT_LIST_HEAD(&call->attend_link);
149 INIT_LIST_HEAD(&call->tx_sendmsg);
150 INIT_LIST_HEAD(&call->tx_buffer);
151 skb_queue_head_init(&call->recvmsg_queue);
152 skb_queue_head_init(&call->rx_oos_queue);
153 init_waitqueue_head(&call->waitq);
154 spin_lock_init(&call->notify_lock);
155 spin_lock_init(&call->tx_lock);
156 refcount_set(&call->ref, 1);
157 call->debug_id = debug_id;
158 call->tx_total_len = -1;
159 call->next_rx_timo = 20 * HZ;
160 call->next_req_timo = 1 * HZ;
161 call->ackr_window = 1;
162 call->ackr_wtop = 1;
163 call->delay_ack_at = KTIME_MAX;
164 call->ack_lost_at = KTIME_MAX;
165 call->resend_at = KTIME_MAX;
166 call->ping_at = KTIME_MAX;
167 call->keepalive_at = KTIME_MAX;
168 call->expect_rx_by = KTIME_MAX;
169 call->expect_req_by = KTIME_MAX;
170 call->expect_term_by = KTIME_MAX;
171
172 memset(&call->sock_node, 0xed, sizeof(call->sock_node));
173
174 call->rx_winsize = rxrpc_rx_window_size;
175 call->tx_winsize = 16;
176
177 call->cong_cwnd = RXRPC_MIN_CWND;
178 call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
179
180 call->rxnet = rxnet;
181 call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
182 atomic_inc(&rxnet->nr_calls);
183 return call;
184}
185
186/*
187 * Allocate a new client call.
188 */
189static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
190 struct rxrpc_conn_parameters *cp,
191 struct rxrpc_call_params *p,
192 gfp_t gfp,
193 unsigned int debug_id)
194{
195 struct rxrpc_call *call;
196 ktime_t now;
197 int ret;
198
199 _enter("");
200
201 call = rxrpc_alloc_call(rx, gfp, debug_id);
202 if (!call)
203 return ERR_PTR(-ENOMEM);
204 now = ktime_get_real();
205 call->acks_latest_ts = now;
206 call->cong_tstamp = now;
207 call->dest_srx = cp->peer->srx;
208 call->dest_srx.srx_service = cp->service_id;
209 call->interruptibility = p->interruptibility;
210 call->tx_total_len = p->tx_total_len;
211 call->key = key_get(cp->key);
212 call->peer = rxrpc_get_peer(cp->peer, rxrpc_peer_get_call);
213 call->local = rxrpc_get_local(cp->local, rxrpc_local_get_call);
214 call->security_level = cp->security_level;
215 if (p->kernel)
216 __set_bit(RXRPC_CALL_KERNEL, &call->flags);
217 if (cp->upgrade)
218 __set_bit(RXRPC_CALL_UPGRADE, &call->flags);
219 if (cp->exclusive)
220 __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
221
222 if (p->timeouts.normal)
223 call->next_rx_timo = min(p->timeouts.normal, 1);
224 if (p->timeouts.idle)
225 call->next_req_timo = min(p->timeouts.idle, 1);
226 if (p->timeouts.hard)
227 call->hard_timo = p->timeouts.hard;
228
229 ret = rxrpc_init_client_call_security(call);
230 if (ret < 0) {
231 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
232 rxrpc_put_call(call, rxrpc_call_put_discard_error);
233 return ERR_PTR(ret);
234 }
235
236 rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
237
238 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
239 p->user_call_ID, rxrpc_call_new_client);
240
241 _leave(" = %p", call);
242 return call;
243}
244
245/*
246 * Initiate the call ack/resend/expiry timer.
247 */
248void rxrpc_start_call_timer(struct rxrpc_call *call)
249{
250 if (call->hard_timo) {
251 ktime_t delay = ms_to_ktime(call->hard_timo * 1000);
252
253 call->expect_term_by = ktime_add(ktime_get_real(), delay);
254 trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
255 }
256 call->timer.expires = jiffies;
257}
258
259/*
260 * Wait for a call slot to become available.
261 */
262static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
263{
264 struct semaphore *limiter = &rxrpc_call_limiter;
265
266 if (p->kernel)
267 limiter = &rxrpc_kernel_call_limiter;
268 if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
269 down(limiter);
270 return limiter;
271 }
272 return down_interruptible(limiter) < 0 ? NULL : limiter;
273}
274
275/*
276 * Release a call slot.
277 */
278static void rxrpc_put_call_slot(struct rxrpc_call *call)
279{
280 struct semaphore *limiter = &rxrpc_call_limiter;
281
282 if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
283 limiter = &rxrpc_kernel_call_limiter;
284 up(limiter);
285}
286
287/*
288 * Start the process of connecting a call. We obtain a peer and a connection
289 * bundle, but the actual association of a call with a connection is offloaded
290 * to the I/O thread to simplify locking.
291 */
292static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
293{
294 struct rxrpc_local *local = call->local;
295 int ret = -ENOMEM;
296
297 _enter("{%d,%lx},", call->debug_id, call->user_call_ID);
298
299 ret = rxrpc_look_up_bundle(call, gfp);
300 if (ret < 0)
301 goto error;
302
303 trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
304 rxrpc_get_call(call, rxrpc_call_get_io_thread);
305 spin_lock(&local->client_call_lock);
306 list_add_tail(&call->wait_link, &local->new_client_calls);
307 spin_unlock(&local->client_call_lock);
308 rxrpc_wake_up_io_thread(local);
309 return 0;
310
311error:
312 __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
313 return ret;
314}
315
316/*
317 * Set up a call for the given parameters.
318 * - Called with the socket lock held, which it must release.
319 * - If it returns a call, the call's lock will need releasing by the caller.
320 */
321struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
322 struct rxrpc_conn_parameters *cp,
323 struct rxrpc_call_params *p,
324 gfp_t gfp,
325 unsigned int debug_id)
326 __releases(&rx->sk.sk_lock.slock)
327 __acquires(&call->user_mutex)
328{
329 struct rxrpc_call *call, *xcall;
330 struct rxrpc_net *rxnet;
331 struct semaphore *limiter;
332 struct rb_node *parent, **pp;
333 int ret;
334
335 _enter("%p,%lx", rx, p->user_call_ID);
336
337 if (WARN_ON_ONCE(!cp->peer)) {
338 release_sock(&rx->sk);
339 return ERR_PTR(-EIO);
340 }
341
342 limiter = rxrpc_get_call_slot(p, gfp);
343 if (!limiter) {
344 release_sock(&rx->sk);
345 return ERR_PTR(-ERESTARTSYS);
346 }
347
348 call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id);
349 if (IS_ERR(call)) {
350 release_sock(&rx->sk);
351 up(limiter);
352 _leave(" = %ld", PTR_ERR(call));
353 return call;
354 }
355
356 /* We need to protect a partially set up call against the user as we
357 * will be acting outside the socket lock.
358 */
359 mutex_lock(&call->user_mutex);
360
361 /* Publish the call, even though it is incompletely set up as yet */
362 write_lock(&rx->call_lock);
363
364 pp = &rx->calls.rb_node;
365 parent = NULL;
366 while (*pp) {
367 parent = *pp;
368 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
369
370 if (p->user_call_ID < xcall->user_call_ID)
371 pp = &(*pp)->rb_left;
372 else if (p->user_call_ID > xcall->user_call_ID)
373 pp = &(*pp)->rb_right;
374 else
375 goto error_dup_user_ID;
376 }
377
378 rcu_assign_pointer(call->socket, rx);
379 call->user_call_ID = p->user_call_ID;
380 __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
381 rxrpc_get_call(call, rxrpc_call_get_userid);
382 rb_link_node(&call->sock_node, parent, pp);
383 rb_insert_color(&call->sock_node, &rx->calls);
384 list_add(&call->sock_link, &rx->sock_calls);
385
386 write_unlock(&rx->call_lock);
387
388 rxnet = call->rxnet;
389 spin_lock(&rxnet->call_lock);
390 list_add_tail_rcu(&call->link, &rxnet->calls);
391 spin_unlock(&rxnet->call_lock);
392
393 /* From this point on, the call is protected by its own lock. */
394 release_sock(&rx->sk);
395
396 /* Set up or get a connection record and set the protocol parameters,
397 * including channel number and call ID.
398 */
399 ret = rxrpc_connect_call(call, gfp);
400 if (ret < 0)
401 goto error_attached_to_socket;
402
403 _leave(" = %p [new]", call);
404 return call;
405
406 /* We unexpectedly found the user ID in the list after taking
407 * the call_lock. This shouldn't happen unless the user races
408 * with itself and tries to add the same user ID twice at the
409 * same time in different threads.
410 */
411error_dup_user_ID:
412 write_unlock(&rx->call_lock);
413 release_sock(&rx->sk);
414 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
415 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
416 rxrpc_call_see_userid_exists);
417 mutex_unlock(&call->user_mutex);
418 rxrpc_put_call(call, rxrpc_call_put_userid_exists);
419 _leave(" = -EEXIST");
420 return ERR_PTR(-EEXIST);
421
422 /* We got an error, but the call is attached to the socket and is in
423 * need of release. However, we might now race with recvmsg() when it
424 * completion notifies the socket. Return 0 from sys_sendmsg() and
425 * leave the error to recvmsg() to deal with.
426 */
427error_attached_to_socket:
428 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
429 rxrpc_call_see_connect_failed);
430 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
431 _leave(" = c=%08x [err]", call->debug_id);
432 return call;
433}
434
435/*
436 * Set up an incoming call. call->conn points to the connection.
437 * This is called in BH context and isn't allowed to fail.
438 */
439void rxrpc_incoming_call(struct rxrpc_sock *rx,
440 struct rxrpc_call *call,
441 struct sk_buff *skb)
442{
443 struct rxrpc_connection *conn = call->conn;
444 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
445 u32 chan;
446
447 _enter(",%d", call->conn->debug_id);
448
449 rcu_assign_pointer(call->socket, rx);
450 call->call_id = sp->hdr.callNumber;
451 call->dest_srx.srx_service = sp->hdr.serviceId;
452 call->cid = sp->hdr.cid;
453 call->cong_tstamp = skb->tstamp;
454
455 __set_bit(RXRPC_CALL_EXPOSED, &call->flags);
456 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
457
458 spin_lock(&conn->state_lock);
459
460 switch (conn->state) {
461 case RXRPC_CONN_SERVICE_UNSECURED:
462 case RXRPC_CONN_SERVICE_CHALLENGING:
463 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
464 break;
465 case RXRPC_CONN_SERVICE:
466 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
467 break;
468
469 case RXRPC_CONN_ABORTED:
470 rxrpc_set_call_completion(call, conn->completion,
471 conn->abort_code, conn->error);
472 break;
473 default:
474 BUG();
475 }
476
477 rxrpc_get_call(call, rxrpc_call_get_io_thread);
478
479 /* Set the channel for this call. We don't get channel_lock as we're
480 * only defending against the data_ready handler (which we're called
481 * from) and the RESPONSE packet parser (which is only really
482 * interested in call_counter and can cope with a disagreement with the
483 * call pointer).
484 */
485 chan = sp->hdr.cid & RXRPC_CHANNELMASK;
486 conn->channels[chan].call_counter = call->call_id;
487 conn->channels[chan].call_id = call->call_id;
488 conn->channels[chan].call = call;
489 spin_unlock(&conn->state_lock);
490
491 spin_lock(&conn->peer->lock);
492 hlist_add_head(&call->error_link, &conn->peer->error_targets);
493 spin_unlock(&conn->peer->lock);
494
495 rxrpc_start_call_timer(call);
496 _leave("");
497}
498
499/*
500 * Note the re-emergence of a call.
501 */
502void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
503{
504 if (call) {
505 int r = refcount_read(&call->ref);
506
507 trace_rxrpc_call(call->debug_id, r, 0, why);
508 }
509}
510
511struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
512 enum rxrpc_call_trace why)
513{
514 int r;
515
516 if (!call || !__refcount_inc_not_zero(&call->ref, &r))
517 return NULL;
518 trace_rxrpc_call(call->debug_id, r + 1, 0, why);
519 return call;
520}
521
522/*
523 * Note the addition of a ref on a call.
524 */
525void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
526{
527 int r;
528
529 __refcount_inc(&call->ref, &r);
530 trace_rxrpc_call(call->debug_id, r + 1, 0, why);
531}
532
533/*
534 * Clean up the Rx skb ring.
535 */
536static void rxrpc_cleanup_ring(struct rxrpc_call *call)
537{
538 rxrpc_purge_queue(&call->recvmsg_queue);
539 rxrpc_purge_queue(&call->rx_oos_queue);
540}
541
542/*
543 * Detach a call from its owning socket.
544 */
545void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
546{
547 struct rxrpc_connection *conn = call->conn;
548 bool put = false, putu = false;
549
550 _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
551
552 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
553 call->flags, rxrpc_call_see_release);
554
555 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
556 BUG();
557
558 rxrpc_put_call_slot(call);
559
560 /* Make sure we don't get any more notifications */
561 spin_lock(&rx->recvmsg_lock);
562
563 if (!list_empty(&call->recvmsg_link)) {
564 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
565 call, call->events, call->flags);
566 list_del(&call->recvmsg_link);
567 put = true;
568 }
569
570 /* list_empty() must return false in rxrpc_notify_socket() */
571 call->recvmsg_link.next = NULL;
572 call->recvmsg_link.prev = NULL;
573
574 spin_unlock(&rx->recvmsg_lock);
575 if (put)
576 rxrpc_put_call(call, rxrpc_call_put_unnotify);
577
578 write_lock(&rx->call_lock);
579
580 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
581 rb_erase(&call->sock_node, &rx->calls);
582 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
583 putu = true;
584 }
585
586 list_del(&call->sock_link);
587 write_unlock(&rx->call_lock);
588
589 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
590
591 if (putu)
592 rxrpc_put_call(call, rxrpc_call_put_userid);
593
594 _leave("");
595}
596
597/*
598 * release all the calls associated with a socket
599 */
600void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
601{
602 struct rxrpc_call *call;
603
604 _enter("%p", rx);
605
606 while (!list_empty(&rx->to_be_accepted)) {
607 call = list_entry(rx->to_be_accepted.next,
608 struct rxrpc_call, accept_link);
609 list_del(&call->accept_link);
610 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
611 rxrpc_abort_call_sock_release_tba);
612 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
613 }
614
615 while (!list_empty(&rx->sock_calls)) {
616 call = list_entry(rx->sock_calls.next,
617 struct rxrpc_call, sock_link);
618 rxrpc_get_call(call, rxrpc_call_get_release_sock);
619 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
620 rxrpc_abort_call_sock_release);
621 rxrpc_release_call(rx, call);
622 rxrpc_put_call(call, rxrpc_call_put_release_sock);
623 }
624
625 _leave("");
626}
627
628/*
629 * release a call
630 */
631void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
632{
633 struct rxrpc_net *rxnet = call->rxnet;
634 unsigned int debug_id = call->debug_id;
635 bool dead;
636 int r;
637
638 ASSERT(call != NULL);
639
640 dead = __refcount_dec_and_test(&call->ref, &r);
641 trace_rxrpc_call(debug_id, r - 1, 0, why);
642 if (dead) {
643 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
644
645 if (!list_empty(&call->link)) {
646 spin_lock(&rxnet->call_lock);
647 list_del_init(&call->link);
648 spin_unlock(&rxnet->call_lock);
649 }
650
651 rxrpc_cleanup_call(call);
652 }
653}
654
655/*
656 * Free up the call under RCU.
657 */
658static void rxrpc_rcu_free_call(struct rcu_head *rcu)
659{
660 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
661 struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
662
663 kmem_cache_free(rxrpc_call_jar, call);
664 if (atomic_dec_and_test(&rxnet->nr_calls))
665 wake_up_var(&rxnet->nr_calls);
666}
667
668/*
669 * Final call destruction - but must be done in process context.
670 */
671static void rxrpc_destroy_call(struct work_struct *work)
672{
673 struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
674 struct rxrpc_txbuf *txb;
675
676 del_timer_sync(&call->timer);
677
678 rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
679 rxrpc_cleanup_ring(call);
680 while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
681 struct rxrpc_txbuf, call_link))) {
682 list_del(&txb->call_link);
683 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
684 }
685 while ((txb = list_first_entry_or_null(&call->tx_buffer,
686 struct rxrpc_txbuf, call_link))) {
687 list_del(&txb->call_link);
688 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
689 }
690
691 rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
692 rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
693 rxrpc_deactivate_bundle(call->bundle);
694 rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
695 rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
696 rxrpc_put_local(call->local, rxrpc_local_put_call);
697 call_rcu(&call->rcu, rxrpc_rcu_free_call);
698}
699
700/*
701 * clean up a call
702 */
703void rxrpc_cleanup_call(struct rxrpc_call *call)
704{
705 memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
706
707 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
708 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
709
710 del_timer(&call->timer);
711
712 if (rcu_read_lock_held())
713 /* Can't use the rxrpc workqueue as we need to cancel/flush
714 * something that may be running/waiting there.
715 */
716 schedule_work(&call->destroyer);
717 else
718 rxrpc_destroy_call(&call->destroyer);
719}
720
721/*
722 * Make sure that all calls are gone from a network namespace. To reach this
723 * point, any open UDP sockets in that namespace must have been closed, so any
724 * outstanding calls cannot be doing I/O.
725 */
726void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
727{
728 struct rxrpc_call *call;
729
730 _enter("");
731
732 if (!list_empty(&rxnet->calls)) {
733 spin_lock(&rxnet->call_lock);
734
735 while (!list_empty(&rxnet->calls)) {
736 call = list_entry(rxnet->calls.next,
737 struct rxrpc_call, link);
738 _debug("Zapping call %p", call);
739
740 rxrpc_see_call(call, rxrpc_call_see_zap);
741 list_del_init(&call->link);
742
743 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
744 call, refcount_read(&call->ref),
745 rxrpc_call_states[__rxrpc_call_state(call)],
746 call->flags, call->events);
747
748 spin_unlock(&rxnet->call_lock);
749 cond_resched();
750 spin_lock(&rxnet->call_lock);
751 }
752
753 spin_unlock(&rxnet->call_lock);
754 }
755
756 atomic_dec(&rxnet->nr_calls);
757 wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
758}