net/rxrpc/call_object.c

   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
  18 const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
  19         [RXRPC_CALL_UNINITIALISED]              = "Uninit  ",
  20         [RXRPC_CALL_CLIENT_AWAIT_CONN]          = "ClWtConn",
  21         [RXRPC_CALL_CLIENT_SEND_REQUEST]        = "ClSndReq",
  22         [RXRPC_CALL_CLIENT_AWAIT_REPLY]         = "ClAwtRpl",
  23         [RXRPC_CALL_CLIENT_RECV_REPLY]          = "ClRcvRpl",
  24         [RXRPC_CALL_SERVER_PREALLOC]            = "SvPrealc",
  25         [RXRPC_CALL_SERVER_SECURING]            = "SvSecure",
  26         [RXRPC_CALL_SERVER_ACCEPTING]           = "SvAccept",
  27         [RXRPC_CALL_SERVER_RECV_REQUEST]        = "SvRcvReq",
  28         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
  29         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
  30         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
  31         [RXRPC_CALL_COMPLETE]                   = "Complete",
  32 };
  33
  34 const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
  35         [RXRPC_CALL_SUCCEEDED]                  = "Complete",
  36         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
  37         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
  38         [RXRPC_CALL_LOCAL_ERROR]                = "LocError",
  39         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
  40 };
  41
  42 struct kmem_cache *rxrpc_call_jar;
  43
  44 static void rxrpc_call_timer_expired(struct timer_list *t)
  45 {
  46         struct rxrpc_call *call = from_timer(call, t, timer);
  47
  48         _enter("%d", call->debug_id);
  49
  50         if (call->state < RXRPC_CALL_COMPLETE) {
  51                 trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
  52                 rxrpc_queue_call(call);
  53         }
  54 }
  55
  56 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
  57
  58 /*
  59  * find an extant server call
  60  * - called in process context with IRQs enabled
  61  */
  62 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
  63                                               unsigned long user_call_ID)
  64 {
  65         struct rxrpc_call *call;
  66         struct rb_node *p;
  67
  68         _enter("%p,%lx", rx, user_call_ID);
  69
  70         read_lock(&rx->call_lock);
  71
  72         p = rx->calls.rb_node;
  73         while (p) {
  74                 call = rb_entry(p, struct rxrpc_call, sock_node);
  75
  76                 if (user_call_ID < call->user_call_ID)
  77                         p = p->rb_left;
  78                 else if (user_call_ID > call->user_call_ID)
  79                         p = p->rb_right;
  80                 else
  81                         goto found_extant_call;
  82         }
  83
  84         read_unlock(&rx->call_lock);
  85         _leave(" = NULL");
  86         return NULL;
  87
  88 found_extant_call:
  89         rxrpc_get_call(call, rxrpc_call_got);
  90         read_unlock(&rx->call_lock);
  91         _leave(" = %p [%d]", call, atomic_read(&call->usage));
  92         return call;
  93 }
  94
  95 /*
  96  * allocate a new call
  97  */
  98 struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
  99                                     unsigned int debug_id)
 100 {
 101         struct rxrpc_call *call;
 102         struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
 103
 104         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 105         if (!call)
 106                 return NULL;
 107
 108         call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
 109                                     sizeof(struct sk_buff *),
 110                                     gfp);
 111         if (!call->rxtx_buffer)
 112                 goto nomem;
 113
 114         call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
 115         if (!call->rxtx_annotations)
 116                 goto nomem_2;
 117
 118         mutex_init(&call->user_mutex);
 119
 120         /* Prevent lockdep reporting a deadlock false positive between the afs
 121          * filesystem and sys_sendmsg() via the mmap sem.
 122          */
 123         if (rx->sk.sk_kern_sock)
 124                 lockdep_set_class(&call->user_mutex,
 125                                   &rxrpc_call_user_mutex_lock_class_key);
 126
 127         timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
 128         INIT_WORK(&call->processor, &rxrpc_process_call);
 129         INIT_LIST_HEAD(&call->link);
 130         INIT_LIST_HEAD(&call->chan_wait_link);
 131         INIT_LIST_HEAD(&call->accept_link);
 132         INIT_LIST_HEAD(&call->recvmsg_link);
 133         INIT_LIST_HEAD(&call->sock_link);
 134         init_waitqueue_head(&call->waitq);
 135         spin_lock_init(&call->lock);
 136         spin_lock_init(&call->notify_lock);
 137         spin_lock_init(&call->input_lock);
 138         rwlock_init(&call->state_lock);
 139         atomic_set(&call->usage, 1);
 140         call->debug_id = debug_id;
 141         call->tx_total_len = -1;
 142         call->next_rx_timo = 20 * HZ;
 143         call->next_req_timo = 1 * HZ;
 144
 145         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 146
 147         /* Leave space in the ring to handle a maxed-out jumbo packet */
 148         call->rx_winsize = rxrpc_rx_window_size;
 149         call->tx_winsize = 16;
 150         call->rx_expect_next = 1;
 151
 152         call->cong_cwnd = 2;
 153         call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
 154
 155         call->rxnet = rxnet;
 156         atomic_inc(&rxnet->nr_calls);
 157         return call;
 158
 159 nomem_2:
 160         kfree(call->rxtx_buffer);
 161 nomem:
 162         kmem_cache_free(rxrpc_call_jar, call);
 163         return NULL;
 164 }
 165
 166 /*
 167  * Allocate a new client call.
 168  */
 169 static 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  */
 196 static 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  */
 216 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 217                                          struct rxrpc_conn_parameters *cp,
 218                                          struct sockaddr_rxrpc *srx,
 219                                          struct rxrpc_call_params *p,
 220                                          gfp_t gfp,
 221                                          unsigned int debug_id)
 222         __releases(&rx->sk.sk_lock.slock)
 223         __acquires(&call->user_mutex)
 224 {
 225         struct rxrpc_call *call, *xcall;
 226         struct rxrpc_net *rxnet;
 227         struct rb_node *parent, **pp;
 228         const void *here = __builtin_return_address(0);
 229         int ret;
 230
 231         _enter("%p,%lx", rx, p->user_call_ID);
 232
 233         call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
 234         if (IS_ERR(call)) {
 235                 release_sock(&rx->sk);
 236                 _leave(" = %ld", PTR_ERR(call));
 237                 return call;
 238         }
 239
 240         if (p->intr)
 241                 __set_bit(RXRPC_CALL_IS_INTR, &call->flags);
 242         call->tx_total_len = p->tx_total_len;
 243         trace_rxrpc_call(call->debug_id, rxrpc_call_new_client,
 244                          atomic_read(&call->usage),
 245                          here, (const void *)p->user_call_ID);
 246
 247         /* We need to protect a partially set up call against the user as we
 248          * will be acting outside the socket lock.
 249          */
 250         mutex_lock(&call->user_mutex);
 251
 252         /* Publish the call, even though it is incompletely set up as yet */
 253         write_lock(&rx->call_lock);
 254
 255         pp = &rx->calls.rb_node;
 256         parent = NULL;
 257         while (*pp) {
 258                 parent = *pp;
 259                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 260
 261                 if (p->user_call_ID < xcall->user_call_ID)
 262                         pp = &(*pp)->rb_left;
 263                 else if (p->user_call_ID > xcall->user_call_ID)
 264                         pp = &(*pp)->rb_right;
 265                 else
 266                         goto error_dup_user_ID;
 267         }
 268
 269         rcu_assign_pointer(call->socket, rx);
 270         call->user_call_ID = p->user_call_ID;
 271         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 272         rxrpc_get_call(call, rxrpc_call_got_userid);
 273         rb_link_node(&call->sock_node, parent, pp);
 274         rb_insert_color(&call->sock_node, &rx->calls);
 275         list_add(&call->sock_link, &rx->sock_calls);
 276
 277         write_unlock(&rx->call_lock);
 278
 279         rxnet = call->rxnet;
 280         write_lock(&rxnet->call_lock);
 281         list_add_tail(&call->link, &rxnet->calls);
 282         write_unlock(&rxnet->call_lock);
 283
 284         /* From this point on, the call is protected by its own lock. */
 285         release_sock(&rx->sk);
 286
 287         /* Set up or get a connection record and set the protocol parameters,
 288          * including channel number and call ID.
 289          */
 290         ret = rxrpc_connect_call(rx, call, cp, srx, gfp);
 291         if (ret < 0)
 292                 goto error;
 293
 294         trace_rxrpc_call(call->debug_id, rxrpc_call_connected,
 295                          atomic_read(&call->usage), here, NULL);
 296
 297         rxrpc_start_call_timer(call);
 298
 299         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 300
 301         _leave(" = %p [new]", call);
 302         return call;
 303
 304         /* We unexpectedly found the user ID in the list after taking
 305          * the call_lock.  This shouldn't happen unless the user races
 306          * with itself and tries to add the same user ID twice at the
 307          * same time in different threads.
 308          */
 309 error_dup_user_ID:
 310         write_unlock(&rx->call_lock);
 311         release_sock(&rx->sk);
 312         ret = -EEXIST;
 313
 314 error:
 315         __rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 316                                     RX_CALL_DEAD, ret);
 317         trace_rxrpc_call(call->debug_id, rxrpc_call_error,
 318                          atomic_read(&call->usage), here, ERR_PTR(ret));
 319         rxrpc_release_call(rx, call);
 320         mutex_unlock(&call->user_mutex);
 321         rxrpc_put_call(call, rxrpc_call_put);
 322         _leave(" = %d", ret);
 323         return ERR_PTR(ret);
 324 }
 325
 326 /*
 327  * Set up an incoming call.  call->conn points to the connection.
 328  * This is called in BH context and isn't allowed to fail.
 329  */
 330 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 331                          struct rxrpc_call *call,
 332                          struct sk_buff *skb)
 333 {
 334         struct rxrpc_connection *conn = call->conn;
 335         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 336         u32 chan;
 337
 338         _enter(",%d", call->conn->debug_id);
 339
 340         rcu_assign_pointer(call->socket, rx);
 341         call->call_id           = sp->hdr.callNumber;
 342         call->service_id        = sp->hdr.serviceId;
 343         call->cid               = sp->hdr.cid;
 344         call->state             = RXRPC_CALL_SERVER_ACCEPTING;
 345         if (sp->hdr.securityIndex > 0)
 346                 call->state     = RXRPC_CALL_SERVER_SECURING;
 347         call->cong_tstamp       = skb->tstamp;
 348
 349         /* Set the channel for this call.  We don't get channel_lock as we're
 350          * only defending against the data_ready handler (which we're called
 351          * from) and the RESPONSE packet parser (which is only really
 352          * interested in call_counter and can cope with a disagreement with the
 353          * call pointer).
 354          */
 355         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 356         conn->channels[chan].call_counter = call->call_id;
 357         conn->channels[chan].call_id = call->call_id;
 358         rcu_assign_pointer(conn->channels[chan].call, call);
 359
 360         spin_lock(&conn->params.peer->lock);
 361         hlist_add_head_rcu(&call->error_link, &conn->params.peer->error_targets);
 362         spin_unlock(&conn->params.peer->lock);
 363
 364         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 365
 366         rxrpc_start_call_timer(call);
 367         _leave("");
 368 }
 369
 370 /*
 371  * Queue a call's work processor, getting a ref to pass to the work queue.
 372  */
 373 bool rxrpc_queue_call(struct rxrpc_call *call)
 374 {
 375         const void *here = __builtin_return_address(0);
 376         int n = atomic_fetch_add_unless(&call->usage, 1, 0);
 377         if (n == 0)
 378                 return false;
 379         if (rxrpc_queue_work(&call->processor))
 380                 trace_rxrpc_call(call->debug_id, rxrpc_call_queued, n + 1,
 381                                  here, NULL);
 382         else
 383                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 384         return true;
 385 }
 386
 387 /*
 388  * Queue a call's work processor, passing the callers ref to the work queue.
 389  */
 390 bool __rxrpc_queue_call(struct rxrpc_call *call)
 391 {
 392         const void *here = __builtin_return_address(0);
 393         int n = atomic_read(&call->usage);
 394         ASSERTCMP(n, >=, 1);
 395         if (rxrpc_queue_work(&call->processor))
 396                 trace_rxrpc_call(call->debug_id, rxrpc_call_queued_ref, n,
 397                                  here, NULL);
 398         else
 399                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 400         return true;
 401 }
 402
 403 /*
 404  * Note the re-emergence of a call.
 405  */
 406 void rxrpc_see_call(struct rxrpc_call *call)
 407 {
 408         const void *here = __builtin_return_address(0);
 409         if (call) {
 410                 int n = atomic_read(&call->usage);
 411
 412                 trace_rxrpc_call(call->debug_id, rxrpc_call_seen, n,
 413                                  here, NULL);
 414         }
 415 }
 416
 417 /*
 418  * Note the addition of a ref on a call.
 419  */
 420 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 421 {
 422         const void *here = __builtin_return_address(0);
 423         int n = atomic_inc_return(&call->usage);
 424
 425         trace_rxrpc_call(call->debug_id, op, n, here, NULL);
 426 }
 427
 428 /*
 429  * Clean up the RxTx skb ring.
 430  */
 431 static void rxrpc_cleanup_ring(struct rxrpc_call *call)
 432 {
 433         int i;
 434
 435         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
 436                 rxrpc_free_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
 437                 call->rxtx_buffer[i] = NULL;
 438         }
 439 }
 440
 441 /*
 442  * Detach a call from its owning socket.
 443  */
 444 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 445 {
 446         const void *here = __builtin_return_address(0);
 447         struct rxrpc_connection *conn = call->conn;
 448         bool put = false;
 449
 450         _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
 451
 452         trace_rxrpc_call(call->debug_id, rxrpc_call_release,
 453                          atomic_read(&call->usage),
 454                          here, (const void *)call->flags);
 455
 456         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 457
 458         spin_lock_bh(&call->lock);
 459         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 460                 BUG();
 461         spin_unlock_bh(&call->lock);
 462
 463         del_timer_sync(&call->timer);
 464
 465         /* Make sure we don't get any more notifications */
 466         write_lock_bh(&rx->recvmsg_lock);
 467
 468         if (!list_empty(&call->recvmsg_link)) {
 469                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 470                        call, call->events, call->flags);
 471                 list_del(&call->recvmsg_link);
 472                 put = true;
 473         }
 474
 475         /* list_empty() must return false in rxrpc_notify_socket() */
 476         call->recvmsg_link.next = NULL;
 477         call->recvmsg_link.prev = NULL;
 478
 479         write_unlock_bh(&rx->recvmsg_lock);
 480         if (put)
 481                 rxrpc_put_call(call, rxrpc_call_put);
 482
 483         write_lock(&rx->call_lock);
 484
 485         if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 486                 rb_erase(&call->sock_node, &rx->calls);
 487                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 488                 rxrpc_put_call(call, rxrpc_call_put_userid);
 489         }
 490
 491         list_del(&call->sock_link);
 492         write_unlock(&rx->call_lock);
 493
 494         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 495
 496         if (conn && !test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
 497                 rxrpc_disconnect_call(call);
 498         if (call->security)
 499                 call->security->free_call_crypto(call);
 500
 501         rxrpc_cleanup_ring(call);
 502         _leave("");
 503 }
 504
 505 /*
 506  * release all the calls associated with a socket
 507  */
 508 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 509 {
 510         struct rxrpc_call *call;
 511
 512         _enter("%p", rx);
 513
 514         while (!list_empty(&rx->to_be_accepted)) {
 515                 call = list_entry(rx->to_be_accepted.next,
 516                                   struct rxrpc_call, accept_link);
 517                 list_del(&call->accept_link);
 518                 rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
 519                 rxrpc_put_call(call, rxrpc_call_put);
 520         }
 521
 522         while (!list_empty(&rx->sock_calls)) {
 523                 call = list_entry(rx->sock_calls.next,
 524                                   struct rxrpc_call, sock_link);
 525                 rxrpc_get_call(call, rxrpc_call_got);
 526                 rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
 527                 rxrpc_send_abort_packet(call);
 528                 rxrpc_release_call(rx, call);
 529                 rxrpc_put_call(call, rxrpc_call_put);
 530         }
 531
 532         _leave("");
 533 }
 534
 535 /*
 536  * release a call
 537  */
 538 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 539 {
 540         struct rxrpc_net *rxnet = call->rxnet;
 541         const void *here = __builtin_return_address(0);
 542         unsigned int debug_id = call->debug_id;
 543         int n;
 544
 545         ASSERT(call != NULL);
 546
 547         n = atomic_dec_return(&call->usage);
 548         trace_rxrpc_call(debug_id, op, n, here, NULL);
 549         ASSERTCMP(n, >=, 0);
 550         if (n == 0) {
 551                 _debug("call %d dead", call->debug_id);
 552                 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 553
 554                 if (!list_empty(&call->link)) {
 555                         write_lock(&rxnet->call_lock);
 556                         list_del_init(&call->link);
 557                         write_unlock(&rxnet->call_lock);
 558                 }
 559
 560                 rxrpc_cleanup_call(call);
 561         }
 562 }
 563
 564 /*
 565  * Final call destruction under RCU.
 566  */
 567 static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
 568 {
 569         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 570         struct rxrpc_net *rxnet = call->rxnet;
 571
 572         rxrpc_put_connection(call->conn);
 573         rxrpc_put_peer(call->peer);
 574         kfree(call->rxtx_buffer);
 575         kfree(call->rxtx_annotations);
 576         kmem_cache_free(rxrpc_call_jar, call);
 577         if (atomic_dec_and_test(&rxnet->nr_calls))
 578                 wake_up_var(&rxnet->nr_calls);
 579 }
 580
 581 /*
 582  * clean up a call
 583  */
 584 void rxrpc_cleanup_call(struct rxrpc_call *call)
 585 {
 586         _net("DESTROY CALL %d", call->debug_id);
 587
 588         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 589
 590         del_timer_sync(&call->timer);
 591
 592         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 593         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 594
 595         rxrpc_cleanup_ring(call);
 596         rxrpc_free_skb(call->tx_pending, rxrpc_skb_cleaned);
 597
 598         call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
 599 }
 600
 601 /*
 602  * Make sure that all calls are gone from a network namespace.  To reach this
 603  * point, any open UDP sockets in that namespace must have been closed, so any
 604  * outstanding calls cannot be doing I/O.
 605  */
 606 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 607 {
 608         struct rxrpc_call *call;
 609
 610         _enter("");
 611
 612         if (!list_empty(&rxnet->calls)) {
 613                 write_lock(&rxnet->call_lock);
 614
 615                 while (!list_empty(&rxnet->calls)) {
 616                         call = list_entry(rxnet->calls.next,
 617                                           struct rxrpc_call, link);
 618                         _debug("Zapping call %p", call);
 619
 620                         rxrpc_see_call(call);
 621                         list_del_init(&call->link);
 622
 623                         pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 624                                call, atomic_read(&call->usage),
 625                                rxrpc_call_states[call->state],
 626                                call->flags, call->events);
 627
 628                         write_unlock(&rxnet->call_lock);
 629                         cond_resched();
 630                         write_lock(&rxnet->call_lock);
 631                 }
 632
 633                 write_unlock(&rxnet->call_lock);
 634         }
 635
 636         atomic_dec(&rxnet->nr_calls);
 637         wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 638 }