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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  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 #include <linux/module.h>
 13 #include <linux/circ_buf.h>
 14 #include <net/sock.h>
 15 #include <net/af_rxrpc.h>
 16 #include "ar-internal.h"
 17 
 18 const char *const rxrpc_call_states[] = {
 19         [RXRPC_CALL_CLIENT_SEND_REQUEST]        = "ClSndReq",
 20         [RXRPC_CALL_CLIENT_AWAIT_REPLY]         = "ClAwtRpl",
 21         [RXRPC_CALL_CLIENT_RECV_REPLY]          = "ClRcvRpl",
 22         [RXRPC_CALL_CLIENT_FINAL_ACK]           = "ClFnlACK",
 23         [RXRPC_CALL_SERVER_SECURING]            = "SvSecure",
 24         [RXRPC_CALL_SERVER_ACCEPTING]           = "SvAccept",
 25         [RXRPC_CALL_SERVER_RECV_REQUEST]        = "SvRcvReq",
 26         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
 27         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
 28         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
 29         [RXRPC_CALL_COMPLETE]                   = "Complete",
 30         [RXRPC_CALL_SERVER_BUSY]                = "SvBusy  ",
 31         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
 32         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
 33         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
 34         [RXRPC_CALL_DEAD]                       = "Dead    ",
 35 };
 36 
 37 struct kmem_cache *rxrpc_call_jar;
 38 LIST_HEAD(rxrpc_calls);
 39 DEFINE_RWLOCK(rxrpc_call_lock);
 40 static unsigned rxrpc_call_max_lifetime = 60;
 41 static unsigned rxrpc_dead_call_timeout = 2;
 42 
 43 static void rxrpc_destroy_call(struct work_struct *work);
 44 static void rxrpc_call_life_expired(unsigned long _call);
 45 static void rxrpc_dead_call_expired(unsigned long _call);
 46 static void rxrpc_ack_time_expired(unsigned long _call);
 47 static void rxrpc_resend_time_expired(unsigned long _call);
 48 
 49 /*
 50  * allocate a new call
 51  */
 52 static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
 53 {
 54         struct rxrpc_call *call;
 55 
 56         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 57         if (!call)
 58                 return NULL;
 59 
 60         call->acks_winsz = 16;
 61         call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
 62                                     gfp);
 63         if (!call->acks_window) {
 64                 kmem_cache_free(rxrpc_call_jar, call);
 65                 return NULL;
 66         }
 67 
 68         setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
 69                     (unsigned long) call);
 70         setup_timer(&call->deadspan, &rxrpc_dead_call_expired,
 71                     (unsigned long) call);
 72         setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
 73                     (unsigned long) call);
 74         setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
 75                     (unsigned long) call);
 76         INIT_WORK(&call->destroyer, &rxrpc_destroy_call);
 77         INIT_WORK(&call->processor, &rxrpc_process_call);
 78         INIT_LIST_HEAD(&call->accept_link);
 79         skb_queue_head_init(&call->rx_queue);
 80         skb_queue_head_init(&call->rx_oos_queue);
 81         init_waitqueue_head(&call->tx_waitq);
 82         spin_lock_init(&call->lock);
 83         rwlock_init(&call->state_lock);
 84         atomic_set(&call->usage, 1);
 85         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 86         call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
 87 
 88         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 89 
 90         call->rx_data_expect = 1;
 91         call->rx_data_eaten = 0;
 92         call->rx_first_oos = 0;
 93         call->ackr_win_top = call->rx_data_eaten + 1 + RXRPC_MAXACKS;
 94         call->creation_jif = jiffies;
 95         return call;
 96 }
 97 
 98 /*
 99  * allocate a new client call and attempt to to get a connection slot for it
100  */
101 static struct rxrpc_call *rxrpc_alloc_client_call(
102         struct rxrpc_sock *rx,
103         struct rxrpc_transport *trans,
104         struct rxrpc_conn_bundle *bundle,
105         gfp_t gfp)
106 {
107         struct rxrpc_call *call;
108         int ret;
109 
110         _enter("");
111 
112         ASSERT(rx != NULL);
113         ASSERT(trans != NULL);
114         ASSERT(bundle != NULL);
115 
116         call = rxrpc_alloc_call(gfp);
117         if (!call)
118                 return ERR_PTR(-ENOMEM);
119 
120         sock_hold(&rx->sk);
121         call->socket = rx;
122         call->rx_data_post = 1;
123 
124         ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
125         if (ret < 0) {
126                 kmem_cache_free(rxrpc_call_jar, call);
127                 return ERR_PTR(ret);
128         }
129 
130         spin_lock(&call->conn->trans->peer->lock);
131         list_add(&call->error_link, &call->conn->trans->peer->error_targets);
132         spin_unlock(&call->conn->trans->peer->lock);
133 
134         call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
135         add_timer(&call->lifetimer);
136 
137         _leave(" = %p", call);
138         return call;
139 }
140 
141 /*
142  * set up a call for the given data
143  * - called in process context with IRQs enabled
144  */
145 struct rxrpc_call *rxrpc_get_client_call(struct rxrpc_sock *rx,
146                                          struct rxrpc_transport *trans,
147                                          struct rxrpc_conn_bundle *bundle,
148                                          unsigned long user_call_ID,
149                                          int create,
150                                          gfp_t gfp)
151 {
152         struct rxrpc_call *call, *candidate;
153         struct rb_node *p, *parent, **pp;
154 
155         _enter("%p,%d,%d,%lx,%d",
156                rx, trans ? trans->debug_id : -1, bundle ? bundle->debug_id : -1,
157                user_call_ID, create);
158 
159         /* search the extant calls first for one that matches the specified
160          * user ID */
161         read_lock(&rx->call_lock);
162 
163         p = rx->calls.rb_node;
164         while (p) {
165                 call = rb_entry(p, struct rxrpc_call, sock_node);
166 
167                 if (user_call_ID < call->user_call_ID)
168                         p = p->rb_left;
169                 else if (user_call_ID > call->user_call_ID)
170                         p = p->rb_right;
171                 else
172                         goto found_extant_call;
173         }
174 
175         read_unlock(&rx->call_lock);
176 
177         if (!create || !trans)
178                 return ERR_PTR(-EBADSLT);
179 
180         /* not yet present - create a candidate for a new record and then
181          * redo the search */
182         candidate = rxrpc_alloc_client_call(rx, trans, bundle, gfp);
183         if (IS_ERR(candidate)) {
184                 _leave(" = %ld", PTR_ERR(candidate));
185                 return candidate;
186         }
187 
188         candidate->user_call_ID = user_call_ID;
189         __set_bit(RXRPC_CALL_HAS_USERID, &candidate->flags);
190 
191         write_lock(&rx->call_lock);
192 
193         pp = &rx->calls.rb_node;
194         parent = NULL;
195         while (*pp) {
196                 parent = *pp;
197                 call = rb_entry(parent, struct rxrpc_call, sock_node);
198 
199                 if (user_call_ID < call->user_call_ID)
200                         pp = &(*pp)->rb_left;
201                 else if (user_call_ID > call->user_call_ID)
202                         pp = &(*pp)->rb_right;
203                 else
204                         goto found_extant_second;
205         }
206 
207         /* second search also failed; add the new call */
208         call = candidate;
209         candidate = NULL;
210         rxrpc_get_call(call);
211 
212         rb_link_node(&call->sock_node, parent, pp);
213         rb_insert_color(&call->sock_node, &rx->calls);
214         write_unlock(&rx->call_lock);
215 
216         write_lock_bh(&rxrpc_call_lock);
217         list_add_tail(&call->link, &rxrpc_calls);
218         write_unlock_bh(&rxrpc_call_lock);
219 
220         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
221 
222         _leave(" = %p [new]", call);
223         return call;
224 
225         /* we found the call in the list immediately */
226 found_extant_call:
227         rxrpc_get_call(call);
228         read_unlock(&rx->call_lock);
229         _leave(" = %p [extant %d]", call, atomic_read(&call->usage));
230         return call;
231 
232         /* we found the call on the second time through the list */
233 found_extant_second:
234         rxrpc_get_call(call);
235         write_unlock(&rx->call_lock);
236         rxrpc_put_call(candidate);
237         _leave(" = %p [second %d]", call, atomic_read(&call->usage));
238         return call;
239 }
240 
241 /*
242  * set up an incoming call
243  * - called in process context with IRQs enabled
244  */
245 struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
246                                        struct rxrpc_connection *conn,
247                                        struct rxrpc_header *hdr,
248                                        gfp_t gfp)
249 {
250         struct rxrpc_call *call, *candidate;
251         struct rb_node **p, *parent;
252         __be32 call_id;
253 
254         _enter(",%d,,%x", conn->debug_id, gfp);
255 
256         ASSERT(rx != NULL);
257 
258         candidate = rxrpc_alloc_call(gfp);
259         if (!candidate)
260                 return ERR_PTR(-EBUSY);
261 
262         candidate->socket = rx;
263         candidate->conn = conn;
264         candidate->cid = hdr->cid;
265         candidate->call_id = hdr->callNumber;
266         candidate->channel = ntohl(hdr->cid) & RXRPC_CHANNELMASK;
267         candidate->rx_data_post = 0;
268         candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
269         if (conn->security_ix > 0)
270                 candidate->state = RXRPC_CALL_SERVER_SECURING;
271 
272         write_lock_bh(&conn->lock);
273 
274         /* set the channel for this call */
275         call = conn->channels[candidate->channel];
276         _debug("channel[%u] is %p", candidate->channel, call);
277         if (call && call->call_id == hdr->callNumber) {
278                 /* already set; must've been a duplicate packet */
279                 _debug("extant call [%d]", call->state);
280                 ASSERTCMP(call->conn, ==, conn);
281 
282                 read_lock(&call->state_lock);
283                 switch (call->state) {
284                 case RXRPC_CALL_LOCALLY_ABORTED:
285                         if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
286                                 rxrpc_queue_call(call);
287                 case RXRPC_CALL_REMOTELY_ABORTED:
288                         read_unlock(&call->state_lock);
289                         goto aborted_call;
290                 default:
291                         rxrpc_get_call(call);
292                         read_unlock(&call->state_lock);
293                         goto extant_call;
294                 }
295         }
296 
297         if (call) {
298                 /* it seems the channel is still in use from the previous call
299                  * - ditch the old binding if its call is now complete */
300                 _debug("CALL: %u { %s }",
301                        call->debug_id, rxrpc_call_states[call->state]);
302 
303                 if (call->state >= RXRPC_CALL_COMPLETE) {
304                         conn->channels[call->channel] = NULL;
305                 } else {
306                         write_unlock_bh(&conn->lock);
307                         kmem_cache_free(rxrpc_call_jar, candidate);
308                         _leave(" = -EBUSY");
309                         return ERR_PTR(-EBUSY);
310                 }
311         }
312 
313         /* check the call number isn't duplicate */
314         _debug("check dup");
315         call_id = hdr->callNumber;
316         p = &conn->calls.rb_node;
317         parent = NULL;
318         while (*p) {
319                 parent = *p;
320                 call = rb_entry(parent, struct rxrpc_call, conn_node);
321 
322                 if (call_id < call->call_id)
323                         p = &(*p)->rb_left;
324                 else if (call_id > call->call_id)
325                         p = &(*p)->rb_right;
326                 else
327                         goto old_call;
328         }
329 
330         /* make the call available */
331         _debug("new call");
332         call = candidate;
333         candidate = NULL;
334         rb_link_node(&call->conn_node, parent, p);
335         rb_insert_color(&call->conn_node, &conn->calls);
336         conn->channels[call->channel] = call;
337         sock_hold(&rx->sk);
338         atomic_inc(&conn->usage);
339         write_unlock_bh(&conn->lock);
340 
341         spin_lock(&conn->trans->peer->lock);
342         list_add(&call->error_link, &conn->trans->peer->error_targets);
343         spin_unlock(&conn->trans->peer->lock);
344 
345         write_lock_bh(&rxrpc_call_lock);
346         list_add_tail(&call->link, &rxrpc_calls);
347         write_unlock_bh(&rxrpc_call_lock);
348 
349         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
350 
351         call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
352         add_timer(&call->lifetimer);
353         _leave(" = %p {%d} [new]", call, call->debug_id);
354         return call;
355 
356 extant_call:
357         write_unlock_bh(&conn->lock);
358         kmem_cache_free(rxrpc_call_jar, candidate);
359         _leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
360         return call;
361 
362 aborted_call:
363         write_unlock_bh(&conn->lock);
364         kmem_cache_free(rxrpc_call_jar, candidate);
365         _leave(" = -ECONNABORTED");
366         return ERR_PTR(-ECONNABORTED);
367 
368 old_call:
369         write_unlock_bh(&conn->lock);
370         kmem_cache_free(rxrpc_call_jar, candidate);
371         _leave(" = -ECONNRESET [old]");
372         return ERR_PTR(-ECONNRESET);
373 }
374 
375 /*
376  * find an extant server call
377  * - called in process context with IRQs enabled
378  */
379 struct rxrpc_call *rxrpc_find_server_call(struct rxrpc_sock *rx,
380                                           unsigned long user_call_ID)
381 {
382         struct rxrpc_call *call;
383         struct rb_node *p;
384 
385         _enter("%p,%lx", rx, user_call_ID);
386 
387         /* search the extant calls for one that matches the specified user
388          * ID */
389         read_lock(&rx->call_lock);
390 
391         p = rx->calls.rb_node;
392         while (p) {
393                 call = rb_entry(p, struct rxrpc_call, sock_node);
394 
395                 if (user_call_ID < call->user_call_ID)
396                         p = p->rb_left;
397                 else if (user_call_ID > call->user_call_ID)
398                         p = p->rb_right;
399                 else
400                         goto found_extant_call;
401         }
402 
403         read_unlock(&rx->call_lock);
404         _leave(" = NULL");
405         return NULL;
406 
407         /* we found the call in the list immediately */
408 found_extant_call:
409         rxrpc_get_call(call);
410         read_unlock(&rx->call_lock);
411         _leave(" = %p [%d]", call, atomic_read(&call->usage));
412         return call;
413 }
414 
415 /*
416  * detach a call from a socket and set up for release
417  */
418 void rxrpc_release_call(struct rxrpc_call *call)
419 {
420         struct rxrpc_connection *conn = call->conn;
421         struct rxrpc_sock *rx = call->socket;
422 
423         _enter("{%d,%d,%d,%d}",
424                call->debug_id, atomic_read(&call->usage),
425                atomic_read(&call->ackr_not_idle),
426                call->rx_first_oos);
427 
428         spin_lock_bh(&call->lock);
429         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
430                 BUG();
431         spin_unlock_bh(&call->lock);
432 
433         /* dissociate from the socket
434          * - the socket's ref on the call is passed to the death timer
435          */
436         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
437 
438         write_lock_bh(&rx->call_lock);
439         if (!list_empty(&call->accept_link)) {
440                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
441                        call, call->events, call->flags);
442                 ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
443                 list_del_init(&call->accept_link);
444                 sk_acceptq_removed(&rx->sk);
445         } else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
446                 rb_erase(&call->sock_node, &rx->calls);
447                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
448                 clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
449         }
450         write_unlock_bh(&rx->call_lock);
451 
452         /* free up the channel for reuse */
453         spin_lock(&conn->trans->client_lock);
454         write_lock_bh(&conn->lock);
455         write_lock(&call->state_lock);
456 
457         if (conn->channels[call->channel] == call)
458                 conn->channels[call->channel] = NULL;
459 
460         if (conn->out_clientflag && conn->bundle) {
461                 conn->avail_calls++;
462                 switch (conn->avail_calls) {
463                 case 1:
464                         list_move_tail(&conn->bundle_link,
465                                        &conn->bundle->avail_conns);
466                 case 2 ... RXRPC_MAXCALLS - 1:
467                         ASSERT(conn->channels[0] == NULL ||
468                                conn->channels[1] == NULL ||
469                                conn->channels[2] == NULL ||
470                                conn->channels[3] == NULL);
471                         break;
472                 case RXRPC_MAXCALLS:
473                         list_move_tail(&conn->bundle_link,
474                                        &conn->bundle->unused_conns);
475                         ASSERT(conn->channels[0] == NULL &&
476                                conn->channels[1] == NULL &&
477                                conn->channels[2] == NULL &&
478                                conn->channels[3] == NULL);
479                         break;
480                 default:
481                         printk(KERN_ERR "RxRPC: conn->avail_calls=%d\n",
482                                conn->avail_calls);
483                         BUG();
484                 }
485         }
486 
487         spin_unlock(&conn->trans->client_lock);
488 
489         if (call->state < RXRPC_CALL_COMPLETE &&
490             call->state != RXRPC_CALL_CLIENT_FINAL_ACK) {
491                 _debug("+++ ABORTING STATE %d +++\n", call->state);
492                 call->state = RXRPC_CALL_LOCALLY_ABORTED;
493                 call->abort_code = RX_CALL_DEAD;
494                 set_bit(RXRPC_CALL_ABORT, &call->events);
495                 rxrpc_queue_call(call);
496         }
497         write_unlock(&call->state_lock);
498         write_unlock_bh(&conn->lock);
499 
500         /* clean up the Rx queue */
501         if (!skb_queue_empty(&call->rx_queue) ||
502             !skb_queue_empty(&call->rx_oos_queue)) {
503                 struct rxrpc_skb_priv *sp;
504                 struct sk_buff *skb;
505 
506                 _debug("purge Rx queues");
507 
508                 spin_lock_bh(&call->lock);
509                 while ((skb = skb_dequeue(&call->rx_queue)) ||
510                        (skb = skb_dequeue(&call->rx_oos_queue))) {
511                         sp = rxrpc_skb(skb);
512                         if (sp->call) {
513                                 ASSERTCMP(sp->call, ==, call);
514                                 rxrpc_put_call(call);
515                                 sp->call = NULL;
516                         }
517                         skb->destructor = NULL;
518                         spin_unlock_bh(&call->lock);
519 
520                         _debug("- zap %s %%%u #%u",
521                                rxrpc_pkts[sp->hdr.type],
522                                ntohl(sp->hdr.serial),
523                                ntohl(sp->hdr.seq));
524                         rxrpc_free_skb(skb);
525                         spin_lock_bh(&call->lock);
526                 }
527                 spin_unlock_bh(&call->lock);
528 
529                 ASSERTCMP(call->state, !=, RXRPC_CALL_COMPLETE);
530         }
531 
532         del_timer_sync(&call->resend_timer);
533         del_timer_sync(&call->ack_timer);
534         del_timer_sync(&call->lifetimer);
535         call->deadspan.expires = jiffies + rxrpc_dead_call_timeout * HZ;
536         add_timer(&call->deadspan);
537 
538         _leave("");
539 }
540 
541 /*
542  * handle a dead call being ready for reaping
543  */
544 static void rxrpc_dead_call_expired(unsigned long _call)
545 {
546         struct rxrpc_call *call = (struct rxrpc_call *) _call;
547 
548         _enter("{%d}", call->debug_id);
549 
550         write_lock_bh(&call->state_lock);
551         call->state = RXRPC_CALL_DEAD;
552         write_unlock_bh(&call->state_lock);
553         rxrpc_put_call(call);
554 }
555 
556 /*
557  * mark a call as to be released, aborting it if it's still in progress
558  * - called with softirqs disabled
559  */
560 static void rxrpc_mark_call_released(struct rxrpc_call *call)
561 {
562         bool sched;
563 
564         write_lock(&call->state_lock);
565         if (call->state < RXRPC_CALL_DEAD) {
566                 sched = false;
567                 if (call->state < RXRPC_CALL_COMPLETE) {
568                         _debug("abort call %p", call);
569                         call->state = RXRPC_CALL_LOCALLY_ABORTED;
570                         call->abort_code = RX_CALL_DEAD;
571                         if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
572                                 sched = true;
573                 }
574                 if (!test_and_set_bit(RXRPC_CALL_RELEASE, &call->events))
575                         sched = true;
576                 if (sched)
577                         rxrpc_queue_call(call);
578         }
579         write_unlock(&call->state_lock);
580 }
581 
582 /*
583  * release all the calls associated with a socket
584  */
585 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
586 {
587         struct rxrpc_call *call;
588         struct rb_node *p;
589 
590         _enter("%p", rx);
591 
592         read_lock_bh(&rx->call_lock);
593 
594         /* mark all the calls as no longer wanting incoming packets */
595         for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
596                 call = rb_entry(p, struct rxrpc_call, sock_node);
597                 rxrpc_mark_call_released(call);
598         }
599 
600         /* kill the not-yet-accepted incoming calls */
601         list_for_each_entry(call, &rx->secureq, accept_link) {
602                 rxrpc_mark_call_released(call);
603         }
604 
605         list_for_each_entry(call, &rx->acceptq, accept_link) {
606                 rxrpc_mark_call_released(call);
607         }
608 
609         read_unlock_bh(&rx->call_lock);
610         _leave("");
611 }
612 
613 /*
614  * release a call
615  */
616 void __rxrpc_put_call(struct rxrpc_call *call)
617 {
618         ASSERT(call != NULL);
619 
620         _enter("%p{u=%d}", call, atomic_read(&call->usage));
621 
622         ASSERTCMP(atomic_read(&call->usage), >, 0);
623 
624         if (atomic_dec_and_test(&call->usage)) {
625                 _debug("call %d dead", call->debug_id);
626                 ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
627                 rxrpc_queue_work(&call->destroyer);
628         }
629         _leave("");
630 }
631 
632 /*
633  * clean up a call
634  */
635 static void rxrpc_cleanup_call(struct rxrpc_call *call)
636 {
637         _net("DESTROY CALL %d", call->debug_id);
638 
639         ASSERT(call->socket);
640 
641         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
642 
643         del_timer_sync(&call->lifetimer);
644         del_timer_sync(&call->deadspan);
645         del_timer_sync(&call->ack_timer);
646         del_timer_sync(&call->resend_timer);
647 
648         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
649         ASSERTCMP(call->events, ==, 0);
650         if (work_pending(&call->processor)) {
651                 _debug("defer destroy");
652                 rxrpc_queue_work(&call->destroyer);
653                 return;
654         }
655 
656         if (call->conn) {
657                 spin_lock(&call->conn->trans->peer->lock);
658                 list_del(&call->error_link);
659                 spin_unlock(&call->conn->trans->peer->lock);
660 
661                 write_lock_bh(&call->conn->lock);
662                 rb_erase(&call->conn_node, &call->conn->calls);
663                 write_unlock_bh(&call->conn->lock);
664                 rxrpc_put_connection(call->conn);
665         }
666 
667         if (call->acks_window) {
668                 _debug("kill Tx window %d",
669                        CIRC_CNT(call->acks_head, call->acks_tail,
670                                 call->acks_winsz));
671                 smp_mb();
672                 while (CIRC_CNT(call->acks_head, call->acks_tail,
673                                 call->acks_winsz) > 0) {
674                         struct rxrpc_skb_priv *sp;
675                         unsigned long _skb;
676 
677                         _skb = call->acks_window[call->acks_tail] & ~1;
678                         sp = rxrpc_skb((struct sk_buff *) _skb);
679                         _debug("+++ clear Tx %u", ntohl(sp->hdr.seq));
680                         rxrpc_free_skb((struct sk_buff *) _skb);
681                         call->acks_tail =
682                                 (call->acks_tail + 1) & (call->acks_winsz - 1);
683                 }
684 
685                 kfree(call->acks_window);
686         }
687 
688         rxrpc_free_skb(call->tx_pending);
689 
690         rxrpc_purge_queue(&call->rx_queue);
691         ASSERT(skb_queue_empty(&call->rx_oos_queue));
692         sock_put(&call->socket->sk);
693         kmem_cache_free(rxrpc_call_jar, call);
694 }
695 
696 /*
697  * destroy a call
698  */
699 static void rxrpc_destroy_call(struct work_struct *work)
700 {
701         struct rxrpc_call *call =
702                 container_of(work, struct rxrpc_call, destroyer);
703 
704         _enter("%p{%d,%d,%p}",
705                call, atomic_read(&call->usage), call->channel, call->conn);
706 
707         ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
708 
709         write_lock_bh(&rxrpc_call_lock);
710         list_del_init(&call->link);
711         write_unlock_bh(&rxrpc_call_lock);
712 
713         rxrpc_cleanup_call(call);
714         _leave("");
715 }
716 
717 /*
718  * preemptively destroy all the call records from a transport endpoint rather
719  * than waiting for them to time out
720  */
721 void __exit rxrpc_destroy_all_calls(void)
722 {
723         struct rxrpc_call *call;
724 
725         _enter("");
726         write_lock_bh(&rxrpc_call_lock);
727 
728         while (!list_empty(&rxrpc_calls)) {
729                 call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
730                 _debug("Zapping call %p", call);
731 
732                 list_del_init(&call->link);
733 
734                 switch (atomic_read(&call->usage)) {
735                 case 0:
736                         ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
737                         break;
738                 case 1:
739                         if (del_timer_sync(&call->deadspan) != 0 &&
740                             call->state != RXRPC_CALL_DEAD)
741                                 rxrpc_dead_call_expired((unsigned long) call);
742                         if (call->state != RXRPC_CALL_DEAD)
743                                 break;
744                 default:
745                         printk(KERN_ERR "RXRPC:"
746                                " Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
747                                call, atomic_read(&call->usage),
748                                atomic_read(&call->ackr_not_idle),
749                                rxrpc_call_states[call->state],
750                                call->flags, call->events);
751                         if (!skb_queue_empty(&call->rx_queue))
752                                 printk(KERN_ERR"RXRPC: Rx queue occupied\n");
753                         if (!skb_queue_empty(&call->rx_oos_queue))
754                                 printk(KERN_ERR"RXRPC: OOS queue occupied\n");
755                         break;
756                 }
757 
758                 write_unlock_bh(&rxrpc_call_lock);
759                 cond_resched();
760                 write_lock_bh(&rxrpc_call_lock);
761         }
762 
763         write_unlock_bh(&rxrpc_call_lock);
764         _leave("");
765 }
766 
767 /*
768  * handle call lifetime being exceeded
769  */
770 static void rxrpc_call_life_expired(unsigned long _call)
771 {
772         struct rxrpc_call *call = (struct rxrpc_call *) _call;
773 
774         if (call->state >= RXRPC_CALL_COMPLETE)
775                 return;
776 
777         _enter("{%d}", call->debug_id);
778         read_lock_bh(&call->state_lock);
779         if (call->state < RXRPC_CALL_COMPLETE) {
780                 set_bit(RXRPC_CALL_LIFE_TIMER, &call->events);
781                 rxrpc_queue_call(call);
782         }
783         read_unlock_bh(&call->state_lock);
784 }
785 
786 /*
787  * handle resend timer expiry
788  */
789 static void rxrpc_resend_time_expired(unsigned long _call)
790 {
791         struct rxrpc_call *call = (struct rxrpc_call *) _call;
792 
793         _enter("{%d}", call->debug_id);
794 
795         if (call->state >= RXRPC_CALL_COMPLETE)
796                 return;
797 
798         read_lock_bh(&call->state_lock);
799         clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
800         if (call->state < RXRPC_CALL_COMPLETE &&
801             !test_and_set_bit(RXRPC_CALL_RESEND_TIMER, &call->events))
802                 rxrpc_queue_call(call);
803         read_unlock_bh(&call->state_lock);
804 }
805 
806 /*
807  * handle ACK timer expiry
808  */
809 static void rxrpc_ack_time_expired(unsigned long _call)
810 {
811         struct rxrpc_call *call = (struct rxrpc_call *) _call;
812 
813         _enter("{%d}", call->debug_id);
814 
815         if (call->state >= RXRPC_CALL_COMPLETE)
816                 return;
817 
818         read_lock_bh(&call->state_lock);
819         if (call->state < RXRPC_CALL_COMPLETE &&
820             !test_and_set_bit(RXRPC_CALL_ACK, &call->events))
821                 rxrpc_queue_call(call);
822         read_unlock_bh(&call->state_lock);
823 }
824 
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