net/rxrpc/call_object.c

   1 /* RxRPC individual remote procedure call handling
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include <linux/circ_buf.h>
  17 #include <linux/spinlock_types.h>
  18 #include <net/sock.h>
  19 #include <net/af_rxrpc.h>
  20 #include "ar-internal.h"
  21
  22 /*
  23  * Maximum lifetime of a call (in jiffies).
  24  */
  25 unsigned int rxrpc_max_call_lifetime = 60 * HZ;
  26
  27 const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
  28         [RXRPC_CALL_UNINITIALISED]              = "Uninit  ",
  29         [RXRPC_CALL_CLIENT_AWAIT_CONN]          = "ClWtConn",
  30         [RXRPC_CALL_CLIENT_SEND_REQUEST]        = "ClSndReq",
  31         [RXRPC_CALL_CLIENT_AWAIT_REPLY]         = "ClAwtRpl",
  32         [RXRPC_CALL_CLIENT_RECV_REPLY]          = "ClRcvRpl",
  33         [RXRPC_CALL_CLIENT_FINAL_ACK]           = "ClFnlACK",
  34         [RXRPC_CALL_SERVER_PREALLOC]            = "SvPrealc",
  35         [RXRPC_CALL_SERVER_SECURING]            = "SvSecure",
  36         [RXRPC_CALL_SERVER_ACCEPTING]           = "SvAccept",
  37         [RXRPC_CALL_SERVER_RECV_REQUEST]        = "SvRcvReq",
  38         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
  39         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
  40         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
  41         [RXRPC_CALL_COMPLETE]                   = "Complete",
  42 };
  43
  44 const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
  45         [RXRPC_CALL_SUCCEEDED]                  = "Complete",
  46         [RXRPC_CALL_SERVER_BUSY]                = "SvBusy  ",
  47         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
  48         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
  49         [RXRPC_CALL_LOCAL_ERROR]                = "LocError",
  50         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
  51 };
  52
  53 const char rxrpc_call_traces[rxrpc_call__nr_trace][4] = {
  54         [rxrpc_call_new_client]         = "NWc",
  55         [rxrpc_call_new_service]        = "NWs",
  56         [rxrpc_call_queued]             = "QUE",
  57         [rxrpc_call_queued_ref]         = "QUR",
  58         [rxrpc_call_seen]               = "SEE",
  59         [rxrpc_call_got]                = "GOT",
  60         [rxrpc_call_got_skb]            = "Gsk",
  61         [rxrpc_call_got_userid]         = "Gus",
  62         [rxrpc_call_put]                = "PUT",
  63         [rxrpc_call_put_skb]            = "Psk",
  64         [rxrpc_call_put_userid]         = "Pus",
  65         [rxrpc_call_put_noqueue]        = "PNQ",
  66 };
  67
  68 struct kmem_cache *rxrpc_call_jar;
  69 LIST_HEAD(rxrpc_calls);
  70 DEFINE_RWLOCK(rxrpc_call_lock);
  71
  72 static void rxrpc_call_life_expired(unsigned long _call);
  73 static void rxrpc_ack_time_expired(unsigned long _call);
  74 static void rxrpc_resend_time_expired(unsigned long _call);
  75
  76 /*
  77  * find an extant server call
  78  * - called in process context with IRQs enabled
  79  */
  80 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
  81                                               unsigned long user_call_ID)
  82 {
  83         struct rxrpc_call *call;
  84         struct rb_node *p;
  85
  86         _enter("%p,%lx", rx, user_call_ID);
  87
  88         read_lock(&rx->call_lock);
  89
  90         p = rx->calls.rb_node;
  91         while (p) {
  92                 call = rb_entry(p, struct rxrpc_call, sock_node);
  93
  94                 if (user_call_ID < call->user_call_ID)
  95                         p = p->rb_left;
  96                 else if (user_call_ID > call->user_call_ID)
  97                         p = p->rb_right;
  98                 else
  99                         goto found_extant_call;
 100         }
 101
 102         read_unlock(&rx->call_lock);
 103         _leave(" = NULL");
 104         return NULL;
 105
 106 found_extant_call:
 107         rxrpc_get_call(call, rxrpc_call_got);
 108         read_unlock(&rx->call_lock);
 109         _leave(" = %p [%d]", call, atomic_read(&call->usage));
 110         return call;
 111 }
 112
 113 /*
 114  * allocate a new call
 115  */
 116 struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
 117 {
 118         struct rxrpc_call *call;
 119
 120         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 121         if (!call)
 122                 return NULL;
 123
 124         call->acks_winsz = 16;
 125         call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
 126                                     gfp);
 127         if (!call->acks_window) {
 128                 kmem_cache_free(rxrpc_call_jar, call);
 129                 return NULL;
 130         }
 131
 132         setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
 133                     (unsigned long) call);
 134         setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
 135                     (unsigned long) call);
 136         setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
 137                     (unsigned long) call);
 138         INIT_WORK(&call->processor, &rxrpc_process_call);
 139         INIT_LIST_HEAD(&call->link);
 140         INIT_LIST_HEAD(&call->chan_wait_link);
 141         INIT_LIST_HEAD(&call->accept_link);
 142         skb_queue_head_init(&call->rx_queue);
 143         skb_queue_head_init(&call->rx_oos_queue);
 144         skb_queue_head_init(&call->knlrecv_queue);
 145         init_waitqueue_head(&call->waitq);
 146         spin_lock_init(&call->lock);
 147         rwlock_init(&call->state_lock);
 148         atomic_set(&call->usage, 1);
 149         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 150
 151         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 152
 153         call->rx_data_expect = 1;
 154         call->rx_data_eaten = 0;
 155         call->rx_first_oos = 0;
 156         call->ackr_win_top = call->rx_data_eaten + 1 + rxrpc_rx_window_size;
 157         call->creation_jif = jiffies;
 158         return call;
 159 }
 160
 161 /*
 162  * Allocate a new client call.
 163  */
 164 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 165                                                   struct sockaddr_rxrpc *srx,
 166                                                   gfp_t gfp)
 167 {
 168         struct rxrpc_call *call;
 169
 170         _enter("");
 171
 172         ASSERT(rx->local != NULL);
 173
 174         call = rxrpc_alloc_call(gfp);
 175         if (!call)
 176                 return ERR_PTR(-ENOMEM);
 177         call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
 178         call->rx_data_post = 1;
 179         call->service_id = srx->srx_service;
 180         rcu_assign_pointer(call->socket, rx);
 181
 182         _leave(" = %p", call);
 183         return call;
 184 }
 185
 186 /*
 187  * Begin client call.
 188  */
 189 static int rxrpc_begin_client_call(struct rxrpc_call *call,
 190                                    struct rxrpc_conn_parameters *cp,
 191                                    struct sockaddr_rxrpc *srx,
 192                                    gfp_t gfp)
 193 {
 194         int ret;
 195
 196         /* Set up or get a connection record and set the protocol parameters,
 197          * including channel number and call ID.
 198          */
 199         ret = rxrpc_connect_call(call, cp, srx, gfp);
 200         if (ret < 0)
 201                 return ret;
 202
 203         spin_lock(&call->conn->params.peer->lock);
 204         hlist_add_head(&call->error_link, &call->conn->params.peer->error_targets);
 205         spin_unlock(&call->conn->params.peer->lock);
 206
 207         call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 208         add_timer(&call->lifetimer);
 209         return 0;
 210 }
 211
 212 /*
 213  * set up a call for the given data
 214  * - called in process context with IRQs enabled
 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                                          unsigned long user_call_ID,
 220                                          gfp_t gfp)
 221 {
 222         struct rxrpc_call *call, *xcall;
 223         struct rb_node *parent, **pp;
 224         const void *here = __builtin_return_address(0);
 225         int ret;
 226
 227         _enter("%p,%lx", rx, user_call_ID);
 228
 229         call = rxrpc_alloc_client_call(rx, srx, gfp);
 230         if (IS_ERR(call)) {
 231                 _leave(" = %ld", PTR_ERR(call));
 232                 return call;
 233         }
 234
 235         trace_rxrpc_call(call, 0, atomic_read(&call->usage), here,
 236                          (const void *)user_call_ID);
 237
 238         /* Publish the call, even though it is incompletely set up as yet */
 239         call->user_call_ID = user_call_ID;
 240         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 241
 242         write_lock(&rx->call_lock);
 243
 244         pp = &rx->calls.rb_node;
 245         parent = NULL;
 246         while (*pp) {
 247                 parent = *pp;
 248                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 249
 250                 if (user_call_ID < xcall->user_call_ID)
 251                         pp = &(*pp)->rb_left;
 252                 else if (user_call_ID > xcall->user_call_ID)
 253                         pp = &(*pp)->rb_right;
 254                 else
 255                         goto found_user_ID_now_present;
 256         }
 257
 258         rxrpc_get_call(call, rxrpc_call_got_userid);
 259         rb_link_node(&call->sock_node, parent, pp);
 260         rb_insert_color(&call->sock_node, &rx->calls);
 261         write_unlock(&rx->call_lock);
 262
 263         write_lock_bh(&rxrpc_call_lock);
 264         list_add_tail(&call->link, &rxrpc_calls);
 265         write_unlock_bh(&rxrpc_call_lock);
 266
 267         ret = rxrpc_begin_client_call(call, cp, srx, gfp);
 268         if (ret < 0)
 269                 goto error;
 270
 271         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 272
 273         _leave(" = %p [new]", call);
 274         return call;
 275
 276 error:
 277         write_lock(&rx->call_lock);
 278         rb_erase(&call->sock_node, &rx->calls);
 279         write_unlock(&rx->call_lock);
 280         rxrpc_put_call(call, rxrpc_call_put_userid);
 281
 282         write_lock_bh(&rxrpc_call_lock);
 283         list_del_init(&call->link);
 284         write_unlock_bh(&rxrpc_call_lock);
 285
 286 error_out:
 287         __rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 288                                     RX_CALL_DEAD, ret);
 289         set_bit(RXRPC_CALL_RELEASED, &call->flags);
 290         rxrpc_put_call(call, rxrpc_call_put);
 291         _leave(" = %d", ret);
 292         return ERR_PTR(ret);
 293
 294         /* We unexpectedly found the user ID in the list after taking
 295          * the call_lock.  This shouldn't happen unless the user races
 296          * with itself and tries to add the same user ID twice at the
 297          * same time in different threads.
 298          */
 299 found_user_ID_now_present:
 300         write_unlock(&rx->call_lock);
 301         ret = -EEXIST;
 302         goto error_out;
 303 }
 304
 305 /*
 306  * set up an incoming call
 307  * - called in process context with IRQs enabled
 308  */
 309 struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
 310                                        struct rxrpc_connection *conn,
 311                                        struct sk_buff *skb)
 312 {
 313         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 314         struct rxrpc_call *call, *candidate;
 315         const void *here = __builtin_return_address(0);
 316         u32 call_id, chan;
 317
 318         _enter(",%d", conn->debug_id);
 319
 320         ASSERT(rx != NULL);
 321
 322         candidate = rxrpc_alloc_call(GFP_NOIO);
 323         if (!candidate)
 324                 return ERR_PTR(-EBUSY);
 325
 326         trace_rxrpc_call(candidate, rxrpc_call_new_service,
 327                          atomic_read(&candidate->usage), here, NULL);
 328
 329         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 330         candidate->conn         = conn;
 331         candidate->peer         = conn->params.peer;
 332         candidate->cid          = sp->hdr.cid;
 333         candidate->call_id      = sp->hdr.callNumber;
 334         candidate->security_ix  = sp->hdr.securityIndex;
 335         candidate->rx_data_post = 0;
 336         candidate->state        = RXRPC_CALL_SERVER_ACCEPTING;
 337         candidate->flags        |= (1 << RXRPC_CALL_IS_SERVICE);
 338         if (conn->security_ix > 0)
 339                 candidate->state = RXRPC_CALL_SERVER_SECURING;
 340         rcu_assign_pointer(candidate->socket, rx);
 341
 342         spin_lock(&conn->channel_lock);
 343
 344         /* set the channel for this call */
 345         call = rcu_dereference_protected(conn->channels[chan].call,
 346                                          lockdep_is_held(&conn->channel_lock));
 347
 348         _debug("channel[%u] is %p", candidate->cid & RXRPC_CHANNELMASK, call);
 349         if (call && call->call_id == sp->hdr.callNumber) {
 350                 /* already set; must've been a duplicate packet */
 351                 _debug("extant call [%d]", call->state);
 352                 ASSERTCMP(call->conn, ==, conn);
 353
 354                 read_lock(&call->state_lock);
 355                 switch (call->state) {
 356                 case RXRPC_CALL_LOCALLY_ABORTED:
 357                         if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events))
 358                                 rxrpc_queue_call(call);
 359                 case RXRPC_CALL_REMOTELY_ABORTED:
 360                         read_unlock(&call->state_lock);
 361                         goto aborted_call;
 362                 default:
 363                         rxrpc_get_call(call, rxrpc_call_got);
 364                         read_unlock(&call->state_lock);
 365                         goto extant_call;
 366                 }
 367         }
 368
 369         if (call) {
 370                 /* it seems the channel is still in use from the previous call
 371                  * - ditch the old binding if its call is now complete */
 372                 _debug("CALL: %u { %s }",
 373                        call->debug_id, rxrpc_call_states[call->state]);
 374
 375                 if (call->state == RXRPC_CALL_COMPLETE) {
 376                         __rxrpc_disconnect_call(conn, call);
 377                 } else {
 378                         spin_unlock(&conn->channel_lock);
 379                         kmem_cache_free(rxrpc_call_jar, candidate);
 380                         _leave(" = -EBUSY");
 381                         return ERR_PTR(-EBUSY);
 382                 }
 383         }
 384
 385         /* check the call number isn't duplicate */
 386         _debug("check dup");
 387         call_id = sp->hdr.callNumber;
 388
 389         /* We just ignore calls prior to the current call ID.  Terminated calls
 390          * are handled via the connection.
 391          */
 392         if (call_id <= conn->channels[chan].call_counter)
 393                 goto old_call; /* TODO: Just drop packet */
 394
 395         /* Temporary: Mirror the backlog prealloc ref (TODO: use prealloc) */
 396         rxrpc_get_call(candidate, rxrpc_call_got);
 397
 398         /* make the call available */
 399         _debug("new call");
 400         call = candidate;
 401         candidate = NULL;
 402         conn->channels[chan].call_counter = call_id;
 403         rcu_assign_pointer(conn->channels[chan].call, call);
 404         rxrpc_get_connection(conn);
 405         rxrpc_get_peer(call->peer);
 406         spin_unlock(&conn->channel_lock);
 407
 408         spin_lock(&conn->params.peer->lock);
 409         hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
 410         spin_unlock(&conn->params.peer->lock);
 411
 412         write_lock_bh(&rxrpc_call_lock);
 413         list_add_tail(&call->link, &rxrpc_calls);
 414         write_unlock_bh(&rxrpc_call_lock);
 415
 416         call->service_id = conn->params.service_id;
 417
 418         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 419
 420         call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 421         add_timer(&call->lifetimer);
 422         _leave(" = %p {%d} [new]", call, call->debug_id);
 423         return call;
 424
 425 extant_call:
 426         spin_unlock(&conn->channel_lock);
 427         kmem_cache_free(rxrpc_call_jar, candidate);
 428         _leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
 429         return call;
 430
 431 aborted_call:
 432         spin_unlock(&conn->channel_lock);
 433         kmem_cache_free(rxrpc_call_jar, candidate);
 434         _leave(" = -ECONNABORTED");
 435         return ERR_PTR(-ECONNABORTED);
 436
 437 old_call:
 438         spin_unlock(&conn->channel_lock);
 439         kmem_cache_free(rxrpc_call_jar, candidate);
 440         _leave(" = -ECONNRESET [old]");
 441         return ERR_PTR(-ECONNRESET);
 442 }
 443
 444 /*
 445  * Queue a call's work processor, getting a ref to pass to the work queue.
 446  */
 447 bool rxrpc_queue_call(struct rxrpc_call *call)
 448 {
 449         const void *here = __builtin_return_address(0);
 450         int n = __atomic_add_unless(&call->usage, 1, 0);
 451         if (n == 0)
 452                 return false;
 453         if (rxrpc_queue_work(&call->processor))
 454                 trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
 455         else
 456                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 457         return true;
 458 }
 459
 460 /*
 461  * Queue a call's work processor, passing the callers ref to the work queue.
 462  */
 463 bool __rxrpc_queue_call(struct rxrpc_call *call)
 464 {
 465         const void *here = __builtin_return_address(0);
 466         int n = atomic_read(&call->usage);
 467         ASSERTCMP(n, >=, 1);
 468         if (rxrpc_queue_work(&call->processor))
 469                 trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
 470         else
 471                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 472         return true;
 473 }
 474
 475 /*
 476  * Note the re-emergence of a call.
 477  */
 478 void rxrpc_see_call(struct rxrpc_call *call)
 479 {
 480         const void *here = __builtin_return_address(0);
 481         if (call) {
 482                 int n = atomic_read(&call->usage);
 483
 484                 trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
 485         }
 486 }
 487
 488 /*
 489  * Note the addition of a ref on a call.
 490  */
 491 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 492 {
 493         const void *here = __builtin_return_address(0);
 494         int n = atomic_inc_return(&call->usage);
 495
 496         trace_rxrpc_call(call, op, n, here, NULL);
 497 }
 498
 499 /*
 500  * Note the addition of a ref on a call for a socket buffer.
 501  */
 502 void rxrpc_get_call_for_skb(struct rxrpc_call *call, struct sk_buff *skb)
 503 {
 504         const void *here = __builtin_return_address(0);
 505         int n = atomic_inc_return(&call->usage);
 506
 507         trace_rxrpc_call(call, rxrpc_call_got_skb, n, here, skb);
 508 }
 509
 510 /*
 511  * detach a call from a socket and set up for release
 512  */
 513 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 514 {
 515         _enter("{%d,%d,%d,%d}",
 516                call->debug_id, atomic_read(&call->usage),
 517                atomic_read(&call->ackr_not_idle),
 518                call->rx_first_oos);
 519
 520         rxrpc_see_call(call);
 521
 522         spin_lock_bh(&call->lock);
 523         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 524                 BUG();
 525         spin_unlock_bh(&call->lock);
 526
 527         /* dissociate from the socket
 528          * - the socket's ref on the call is passed to the death timer
 529          */
 530         _debug("RELEASE CALL %p (%d)", call, call->debug_id);
 531
 532         if (call->peer) {
 533                 spin_lock(&call->peer->lock);
 534                 hlist_del_init(&call->error_link);
 535                 spin_unlock(&call->peer->lock);
 536         }
 537
 538         write_lock_bh(&rx->call_lock);
 539         if (!list_empty(&call->accept_link)) {
 540                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 541                        call, call->events, call->flags);
 542                 ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
 543                 list_del_init(&call->accept_link);
 544                 sk_acceptq_removed(&rx->sk);
 545         } else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 546                 rb_erase(&call->sock_node, &rx->calls);
 547                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 548                 clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 549                 rxrpc_put_call(call, rxrpc_call_put_userid);
 550         }
 551         write_unlock_bh(&rx->call_lock);
 552
 553         /* free up the channel for reuse */
 554         if (call->state == RXRPC_CALL_CLIENT_FINAL_ACK) {
 555                 clear_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events);
 556                 rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK);
 557                 rxrpc_call_completed(call);
 558         } else {
 559                 write_lock_bh(&call->state_lock);
 560
 561                 if (call->state < RXRPC_CALL_COMPLETE) {
 562                         _debug("+++ ABORTING STATE %d +++\n", call->state);
 563                         __rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, ECONNRESET);
 564                         clear_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events);
 565                         rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ABORT);
 566                 }
 567
 568                 write_unlock_bh(&call->state_lock);
 569         }
 570
 571         if (call->conn)
 572                 rxrpc_disconnect_call(call);
 573
 574         /* clean up the Rx queue */
 575         if (!skb_queue_empty(&call->rx_queue) ||
 576             !skb_queue_empty(&call->rx_oos_queue)) {
 577                 struct rxrpc_skb_priv *sp;
 578                 struct sk_buff *skb;
 579
 580                 _debug("purge Rx queues");
 581
 582                 spin_lock_bh(&call->lock);
 583                 while ((skb = skb_dequeue(&call->rx_queue)) ||
 584                        (skb = skb_dequeue(&call->rx_oos_queue))) {
 585                         spin_unlock_bh(&call->lock);
 586
 587                         sp = rxrpc_skb(skb);
 588                         _debug("- zap %s %%%u #%u",
 589                                rxrpc_pkts[sp->hdr.type],
 590                                sp->hdr.serial, sp->hdr.seq);
 591                         rxrpc_free_skb(skb);
 592                         spin_lock_bh(&call->lock);
 593                 }
 594                 spin_unlock_bh(&call->lock);
 595         }
 596         rxrpc_purge_queue(&call->knlrecv_queue);
 597
 598         del_timer_sync(&call->resend_timer);
 599         del_timer_sync(&call->ack_timer);
 600         del_timer_sync(&call->lifetimer);
 601
 602         /* We have to release the prealloc backlog ref */
 603         if (rxrpc_is_service_call(call))
 604                 rxrpc_put_call(call, rxrpc_call_put);
 605         _leave("");
 606 }
 607
 608 /*
 609  * release all the calls associated with a socket
 610  */
 611 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 612 {
 613         struct rxrpc_call *call;
 614         struct rb_node *p;
 615
 616         _enter("%p", rx);
 617
 618         read_lock_bh(&rx->call_lock);
 619
 620         /* kill the not-yet-accepted incoming calls */
 621         list_for_each_entry(call, &rx->secureq, accept_link) {
 622                 rxrpc_release_call(rx, call);
 623         }
 624
 625         list_for_each_entry(call, &rx->acceptq, accept_link) {
 626                 rxrpc_release_call(rx, call);
 627         }
 628
 629         /* mark all the calls as no longer wanting incoming packets */
 630         for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
 631                 call = rb_entry(p, struct rxrpc_call, sock_node);
 632                 rxrpc_release_call(rx, call);
 633         }
 634
 635         read_unlock_bh(&rx->call_lock);
 636         _leave("");
 637 }
 638
 639 /*
 640  * release a call
 641  */
 642 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 643 {
 644         const void *here = __builtin_return_address(0);
 645         int n;
 646
 647         ASSERT(call != NULL);
 648
 649         n = atomic_dec_return(&call->usage);
 650         trace_rxrpc_call(call, op, n, here, NULL);
 651         ASSERTCMP(n, >=, 0);
 652         if (n == 0) {
 653                 _debug("call %d dead", call->debug_id);
 654                 rxrpc_cleanup_call(call);
 655         }
 656 }
 657
 658 /*
 659  * Release a call ref held by a socket buffer.
 660  */
 661 void rxrpc_put_call_for_skb(struct rxrpc_call *call, struct sk_buff *skb)
 662 {
 663         const void *here = __builtin_return_address(0);
 664         int n;
 665
 666         n = atomic_dec_return(&call->usage);
 667         trace_rxrpc_call(call, rxrpc_call_put_skb, n, here, skb);
 668         ASSERTCMP(n, >=, 0);
 669         if (n == 0) {
 670                 _debug("call %d dead", call->debug_id);
 671                 rxrpc_cleanup_call(call);
 672         }
 673 }
 674
 675 /*
 676  * Final call destruction under RCU.
 677  */
 678 static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
 679 {
 680         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 681
 682         rxrpc_purge_queue(&call->rx_queue);
 683         rxrpc_purge_queue(&call->knlrecv_queue);
 684         rxrpc_put_peer(call->peer);
 685         kmem_cache_free(rxrpc_call_jar, call);
 686 }
 687
 688 /*
 689  * clean up a call
 690  */
 691 void rxrpc_cleanup_call(struct rxrpc_call *call)
 692 {
 693         _net("DESTROY CALL %d", call->debug_id);
 694
 695         write_lock_bh(&rxrpc_call_lock);
 696         list_del_init(&call->link);
 697         write_unlock_bh(&rxrpc_call_lock);
 698
 699         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 700
 701         del_timer_sync(&call->lifetimer);
 702         del_timer_sync(&call->ack_timer);
 703         del_timer_sync(&call->resend_timer);
 704
 705         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 706         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 707         ASSERT(!work_pending(&call->processor));
 708         ASSERTCMP(call->conn, ==, NULL);
 709
 710         if (call->acks_window) {
 711                 _debug("kill Tx window %d",
 712                        CIRC_CNT(call->acks_head, call->acks_tail,
 713                                 call->acks_winsz));
 714                 smp_mb();
 715                 while (CIRC_CNT(call->acks_head, call->acks_tail,
 716                                 call->acks_winsz) > 0) {
 717                         struct rxrpc_skb_priv *sp;
 718                         unsigned long _skb;
 719
 720                         _skb = call->acks_window[call->acks_tail] & ~1;
 721                         sp = rxrpc_skb((struct sk_buff *)_skb);
 722                         _debug("+++ clear Tx %u", sp->hdr.seq);
 723                         rxrpc_free_skb((struct sk_buff *)_skb);
 724                         call->acks_tail =
 725                                 (call->acks_tail + 1) & (call->acks_winsz - 1);
 726                 }
 727
 728                 kfree(call->acks_window);
 729         }
 730
 731         rxrpc_free_skb(call->tx_pending);
 732
 733         rxrpc_purge_queue(&call->rx_queue);
 734         ASSERT(skb_queue_empty(&call->rx_oos_queue));
 735         rxrpc_purge_queue(&call->knlrecv_queue);
 736         call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
 737 }
 738
 739 /*
 740  * Make sure that all calls are gone.
 741  */
 742 void __exit rxrpc_destroy_all_calls(void)
 743 {
 744         struct rxrpc_call *call;
 745
 746         _enter("");
 747
 748         if (list_empty(&rxrpc_calls))
 749                 return;
 750
 751         write_lock_bh(&rxrpc_call_lock);
 752
 753         while (!list_empty(&rxrpc_calls)) {
 754                 call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
 755                 _debug("Zapping call %p", call);
 756
 757                 rxrpc_see_call(call);
 758                 list_del_init(&call->link);
 759
 760                 pr_err("Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
 761                        call, atomic_read(&call->usage),
 762                        atomic_read(&call->ackr_not_idle),
 763                        rxrpc_call_states[call->state],
 764                        call->flags, call->events);
 765                 if (!skb_queue_empty(&call->rx_queue))
 766                         pr_err("Rx queue occupied\n");
 767                 if (!skb_queue_empty(&call->rx_oos_queue))
 768                         pr_err("OOS queue occupied\n");
 769
 770                 write_unlock_bh(&rxrpc_call_lock);
 771                 cond_resched();
 772                 write_lock_bh(&rxrpc_call_lock);
 773         }
 774
 775         write_unlock_bh(&rxrpc_call_lock);
 776         _leave("");
 777 }
 778
 779 /*
 780  * handle call lifetime being exceeded
 781  */
 782 static void rxrpc_call_life_expired(unsigned long _call)
 783 {
 784         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 785
 786         _enter("{%d}", call->debug_id);
 787
 788         rxrpc_see_call(call);
 789         if (call->state >= RXRPC_CALL_COMPLETE)
 790                 return;
 791
 792         set_bit(RXRPC_CALL_EV_LIFE_TIMER, &call->events);
 793         rxrpc_queue_call(call);
 794 }
 795
 796 /*
 797  * handle resend timer expiry
 798  * - may not take call->state_lock as this can deadlock against del_timer_sync()
 799  */
 800 static void rxrpc_resend_time_expired(unsigned long _call)
 801 {
 802         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 803
 804         _enter("{%d}", call->debug_id);
 805
 806         rxrpc_see_call(call);
 807         if (call->state >= RXRPC_CALL_COMPLETE)
 808                 return;
 809
 810         clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
 811         if (!test_and_set_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events))
 812                 rxrpc_queue_call(call);
 813 }
 814
 815 /*
 816  * handle ACK timer expiry
 817  */
 818 static void rxrpc_ack_time_expired(unsigned long _call)
 819 {
 820         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 821
 822         _enter("{%d}", call->debug_id);
 823
 824         rxrpc_see_call(call);
 825         if (call->state >= RXRPC_CALL_COMPLETE)
 826                 return;
 827
 828         if (!test_and_set_bit(RXRPC_CALL_EV_ACK, &call->events))
 829                 rxrpc_queue_call(call);
 830 }