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 const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
  23         [RXRPC_CALL_UNINITIALISED]              = "Uninit  ",
  24         [RXRPC_CALL_CLIENT_AWAIT_CONN]          = "ClWtConn",
  25         [RXRPC_CALL_CLIENT_SEND_REQUEST]        = "ClSndReq",
  26         [RXRPC_CALL_CLIENT_AWAIT_REPLY]         = "ClAwtRpl",
  27         [RXRPC_CALL_CLIENT_RECV_REPLY]          = "ClRcvRpl",
  28         [RXRPC_CALL_SERVER_PREALLOC]            = "SvPrealc",
  29         [RXRPC_CALL_SERVER_SECURING]            = "SvSecure",
  30         [RXRPC_CALL_SERVER_ACCEPTING]           = "SvAccept",
  31         [RXRPC_CALL_SERVER_RECV_REQUEST]        = "SvRcvReq",
  32         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
  33         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
  34         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
  35         [RXRPC_CALL_COMPLETE]                   = "Complete",
  36 };
  37
  38 const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
  39         [RXRPC_CALL_SUCCEEDED]                  = "Complete",
  40         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
  41         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
  42         [RXRPC_CALL_LOCAL_ERROR]                = "LocError",
  43         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
  44 };
  45
  46 struct kmem_cache *rxrpc_call_jar;
  47
  48 static void rxrpc_call_timer_expired(struct timer_list *t)
  49 {
  50         struct rxrpc_call *call = from_timer(call, t, timer);
  51
  52         _enter("%d", call->debug_id);
  53
  54         if (call->state < RXRPC_CALL_COMPLETE) {
  55                 trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
  56                 rxrpc_queue_call(call);
  57         }
  58 }
  59
  60 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
  61
  62 /*
  63  * find an extant server call
  64  * - called in process context with IRQs enabled
  65  */
  66 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
  67                                               unsigned long user_call_ID)
  68 {
  69         struct rxrpc_call *call;
  70         struct rb_node *p;
  71
  72         _enter("%p,%lx", rx, user_call_ID);
  73
  74         read_lock(&rx->call_lock);
  75
  76         p = rx->calls.rb_node;
  77         while (p) {
  78                 call = rb_entry(p, struct rxrpc_call, sock_node);
  79
  80                 if (user_call_ID < call->user_call_ID)
  81                         p = p->rb_left;
  82                 else if (user_call_ID > call->user_call_ID)
  83                         p = p->rb_right;
  84                 else
  85                         goto found_extant_call;
  86         }
  87
  88         read_unlock(&rx->call_lock);
  89         _leave(" = NULL");
  90         return NULL;
  91
  92 found_extant_call:
  93         rxrpc_get_call(call, rxrpc_call_got);
  94         read_unlock(&rx->call_lock);
  95         _leave(" = %p [%d]", call, atomic_read(&call->usage));
  96         return call;
  97 }
  98
  99 /*
 100  * allocate a new call
 101  */
 102 struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp)
 103 {
 104         struct rxrpc_call *call;
 105
 106         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 107         if (!call)
 108                 return NULL;
 109
 110         call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
 111                                     sizeof(struct sk_buff *),
 112                                     gfp);
 113         if (!call->rxtx_buffer)
 114                 goto nomem;
 115
 116         call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
 117         if (!call->rxtx_annotations)
 118                 goto nomem_2;
 119
 120         mutex_init(&call->user_mutex);
 121
 122         /* Prevent lockdep reporting a deadlock false positive between the afs
 123          * filesystem and sys_sendmsg() via the mmap sem.
 124          */
 125         if (rx->sk.sk_kern_sock)
 126                 lockdep_set_class(&call->user_mutex,
 127                                   &rxrpc_call_user_mutex_lock_class_key);
 128
 129         timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
 130         INIT_WORK(&call->processor, &rxrpc_process_call);
 131         INIT_LIST_HEAD(&call->link);
 132         INIT_LIST_HEAD(&call->chan_wait_link);
 133         INIT_LIST_HEAD(&call->accept_link);
 134         INIT_LIST_HEAD(&call->recvmsg_link);
 135         INIT_LIST_HEAD(&call->sock_link);
 136         init_waitqueue_head(&call->waitq);
 137         spin_lock_init(&call->lock);
 138         spin_lock_init(&call->notify_lock);
 139         rwlock_init(&call->state_lock);
 140         atomic_set(&call->usage, 1);
 141         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 142         call->tx_total_len = -1;
 143         call->next_rx_timo = 20 * HZ;
 144         call->next_req_timo = 1 * HZ;
 145
 146         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 147
 148         /* Leave space in the ring to handle a maxed-out jumbo packet */
 149         call->rx_winsize = rxrpc_rx_window_size;
 150         call->tx_winsize = 16;
 151         call->rx_expect_next = 1;
 152
 153         call->cong_cwnd = 2;
 154         call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
 155         return call;
 156
 157 nomem_2:
 158         kfree(call->rxtx_buffer);
 159 nomem:
 160         kmem_cache_free(rxrpc_call_jar, call);
 161         return NULL;
 162 }
 163
 164 /*
 165  * Allocate a new client call.
 166  */
 167 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 168                                                   struct sockaddr_rxrpc *srx,
 169                                                   gfp_t gfp)
 170 {
 171         struct rxrpc_call *call;
 172         ktime_t now;
 173
 174         _enter("");
 175
 176         call = rxrpc_alloc_call(rx, gfp);
 177         if (!call)
 178                 return ERR_PTR(-ENOMEM);
 179         call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
 180         call->service_id = srx->srx_service;
 181         call->tx_phase = true;
 182         now = ktime_get_real();
 183         call->acks_latest_ts = now;
 184         call->cong_tstamp = now;
 185
 186         _leave(" = %p", call);
 187         return call;
 188 }
 189
 190 /*
 191  * Initiate the call ack/resend/expiry timer.
 192  */
 193 static void rxrpc_start_call_timer(struct rxrpc_call *call)
 194 {
 195         unsigned long now = jiffies;
 196         unsigned long j = now + MAX_JIFFY_OFFSET;
 197
 198         call->ack_at = j;
 199         call->ack_lost_at = j;
 200         call->resend_at = j;
 201         call->ping_at = j;
 202         call->expect_rx_by = j;
 203         call->expect_req_by = j;
 204         call->expect_term_by = j;
 205         call->timer.expires = now;
 206 }
 207
 208 /*
 209  * Set up a call for the given parameters.
 210  * - Called with the socket lock held, which it must release.
 211  * - If it returns a call, the call's lock will need releasing by the caller.
 212  */
 213 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 214                                          struct rxrpc_conn_parameters *cp,
 215                                          struct sockaddr_rxrpc *srx,
 216                                          struct rxrpc_call_params *p,
 217                                          gfp_t gfp)
 218         __releases(&rx->sk.sk_lock.slock)
 219 {
 220         struct rxrpc_call *call, *xcall;
 221         struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
 222         struct rb_node *parent, **pp;
 223         const void *here = __builtin_return_address(0);
 224         int ret;
 225
 226         _enter("%p,%lx", rx, p->user_call_ID);
 227
 228         call = rxrpc_alloc_client_call(rx, srx, gfp);
 229         if (IS_ERR(call)) {
 230                 release_sock(&rx->sk);
 231                 _leave(" = %ld", PTR_ERR(call));
 232                 return call;
 233         }
 234
 235         call->tx_total_len = p->tx_total_len;
 236         trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
 237                          here, (const void *)p->user_call_ID);
 238
 239         /* We need to protect a partially set up call against the user as we
 240          * will be acting outside the socket lock.
 241          */
 242         mutex_lock(&call->user_mutex);
 243
 244         /* Publish the call, even though it is incompletely set up as yet */
 245         write_lock(&rx->call_lock);
 246
 247         pp = &rx->calls.rb_node;
 248         parent = NULL;
 249         while (*pp) {
 250                 parent = *pp;
 251                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 252
 253                 if (p->user_call_ID < xcall->user_call_ID)
 254                         pp = &(*pp)->rb_left;
 255                 else if (p->user_call_ID > xcall->user_call_ID)
 256                         pp = &(*pp)->rb_right;
 257                 else
 258                         goto error_dup_user_ID;
 259         }
 260
 261         rcu_assign_pointer(call->socket, rx);
 262         call->user_call_ID = p->user_call_ID;
 263         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 264         rxrpc_get_call(call, rxrpc_call_got_userid);
 265         rb_link_node(&call->sock_node, parent, pp);
 266         rb_insert_color(&call->sock_node, &rx->calls);
 267         list_add(&call->sock_link, &rx->sock_calls);
 268
 269         write_unlock(&rx->call_lock);
 270
 271         write_lock(&rxnet->call_lock);
 272         list_add_tail(&call->link, &rxnet->calls);
 273         write_unlock(&rxnet->call_lock);
 274
 275         /* From this point on, the call is protected by its own lock. */
 276         release_sock(&rx->sk);
 277
 278         /* Set up or get a connection record and set the protocol parameters,
 279          * including channel number and call ID.
 280          */
 281         ret = rxrpc_connect_call(call, cp, srx, gfp);
 282         if (ret < 0)
 283                 goto error;
 284
 285         trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
 286                          here, NULL);
 287
 288         rxrpc_start_call_timer(call);
 289
 290         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 291
 292         _leave(" = %p [new]", call);
 293         return call;
 294
 295         /* We unexpectedly found the user ID in the list after taking
 296          * the call_lock.  This shouldn't happen unless the user races
 297          * with itself and tries to add the same user ID twice at the
 298          * same time in different threads.
 299          */
 300 error_dup_user_ID:
 301         write_unlock(&rx->call_lock);
 302         release_sock(&rx->sk);
 303         ret = -EEXIST;
 304
 305 error:
 306         __rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 307                                     RX_CALL_DEAD, ret);
 308         trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
 309                          here, ERR_PTR(ret));
 310         rxrpc_release_call(rx, call);
 311         mutex_unlock(&call->user_mutex);
 312         rxrpc_put_call(call, rxrpc_call_put);
 313         _leave(" = %d", ret);
 314         return ERR_PTR(ret);
 315 }
 316
 317 /*
 318  * Retry a call to a new address.  It is expected that the Tx queue of the call
 319  * will contain data previously packaged for an old call.
 320  */
 321 int rxrpc_retry_client_call(struct rxrpc_sock *rx,
 322                             struct rxrpc_call *call,
 323                             struct rxrpc_conn_parameters *cp,
 324                             struct sockaddr_rxrpc *srx,
 325                             gfp_t gfp)
 326 {
 327         const void *here = __builtin_return_address(0);
 328         int ret;
 329
 330         /* Set up or get a connection record and set the protocol parameters,
 331          * including channel number and call ID.
 332          */
 333         ret = rxrpc_connect_call(call, cp, srx, gfp);
 334         if (ret < 0)
 335                 goto error;
 336
 337         trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
 338                          here, NULL);
 339
 340         rxrpc_start_call_timer(call);
 341
 342         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 343
 344         if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 345                 rxrpc_queue_call(call);
 346
 347         _leave(" = 0");
 348         return 0;
 349
 350 error:
 351         rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 352                                   RX_CALL_DEAD, ret);
 353         trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
 354                          here, ERR_PTR(ret));
 355         _leave(" = %d", ret);
 356         return ret;
 357 }
 358
 359 /*
 360  * Set up an incoming call.  call->conn points to the connection.
 361  * This is called in BH context and isn't allowed to fail.
 362  */
 363 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 364                          struct rxrpc_call *call,
 365                          struct sk_buff *skb)
 366 {
 367         struct rxrpc_connection *conn = call->conn;
 368         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 369         u32 chan;
 370
 371         _enter(",%d", call->conn->debug_id);
 372
 373         rcu_assign_pointer(call->socket, rx);
 374         call->call_id           = sp->hdr.callNumber;
 375         call->service_id        = sp->hdr.serviceId;
 376         call->cid               = sp->hdr.cid;
 377         call->state             = RXRPC_CALL_SERVER_ACCEPTING;
 378         if (sp->hdr.securityIndex > 0)
 379                 call->state     = RXRPC_CALL_SERVER_SECURING;
 380         call->cong_tstamp       = skb->tstamp;
 381
 382         /* Set the channel for this call.  We don't get channel_lock as we're
 383          * only defending against the data_ready handler (which we're called
 384          * from) and the RESPONSE packet parser (which is only really
 385          * interested in call_counter and can cope with a disagreement with the
 386          * call pointer).
 387          */
 388         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 389         conn->channels[chan].call_counter = call->call_id;
 390         conn->channels[chan].call_id = call->call_id;
 391         rcu_assign_pointer(conn->channels[chan].call, call);
 392
 393         spin_lock(&conn->params.peer->lock);
 394         hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
 395         spin_unlock(&conn->params.peer->lock);
 396
 397         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 398
 399         rxrpc_start_call_timer(call);
 400         _leave("");
 401 }
 402
 403 /*
 404  * Queue a call's work processor, getting a ref to pass to the work queue.
 405  */
 406 bool rxrpc_queue_call(struct rxrpc_call *call)
 407 {
 408         const void *here = __builtin_return_address(0);
 409         int n = __atomic_add_unless(&call->usage, 1, 0);
 410         if (n == 0)
 411                 return false;
 412         if (rxrpc_queue_work(&call->processor))
 413                 trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
 414         else
 415                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 416         return true;
 417 }
 418
 419 /*
 420  * Queue a call's work processor, passing the callers ref to the work queue.
 421  */
 422 bool __rxrpc_queue_call(struct rxrpc_call *call)
 423 {
 424         const void *here = __builtin_return_address(0);
 425         int n = atomic_read(&call->usage);
 426         ASSERTCMP(n, >=, 1);
 427         if (rxrpc_queue_work(&call->processor))
 428                 trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
 429         else
 430                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 431         return true;
 432 }
 433
 434 /*
 435  * Note the re-emergence of a call.
 436  */
 437 void rxrpc_see_call(struct rxrpc_call *call)
 438 {
 439         const void *here = __builtin_return_address(0);
 440         if (call) {
 441                 int n = atomic_read(&call->usage);
 442
 443                 trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
 444         }
 445 }
 446
 447 /*
 448  * Note the addition of a ref on a call.
 449  */
 450 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 451 {
 452         const void *here = __builtin_return_address(0);
 453         int n = atomic_inc_return(&call->usage);
 454
 455         trace_rxrpc_call(call, op, n, here, NULL);
 456 }
 457
 458 /*
 459  * Detach a call from its owning socket.
 460  */
 461 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 462 {
 463         const void *here = __builtin_return_address(0);
 464         struct rxrpc_connection *conn = call->conn;
 465         bool put = false;
 466         int i;
 467
 468         _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
 469
 470         trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
 471                          here, (const void *)call->flags);
 472
 473         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 474
 475         spin_lock_bh(&call->lock);
 476         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 477                 BUG();
 478         spin_unlock_bh(&call->lock);
 479
 480         del_timer_sync(&call->timer);
 481
 482         /* Make sure we don't get any more notifications */
 483         write_lock_bh(&rx->recvmsg_lock);
 484
 485         if (!list_empty(&call->recvmsg_link)) {
 486                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 487                        call, call->events, call->flags);
 488                 list_del(&call->recvmsg_link);
 489                 put = true;
 490         }
 491
 492         /* list_empty() must return false in rxrpc_notify_socket() */
 493         call->recvmsg_link.next = NULL;
 494         call->recvmsg_link.prev = NULL;
 495
 496         write_unlock_bh(&rx->recvmsg_lock);
 497         if (put)
 498                 rxrpc_put_call(call, rxrpc_call_put);
 499
 500         write_lock(&rx->call_lock);
 501
 502         if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 503                 rb_erase(&call->sock_node, &rx->calls);
 504                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 505                 rxrpc_put_call(call, rxrpc_call_put_userid);
 506         }
 507
 508         list_del(&call->sock_link);
 509         write_unlock(&rx->call_lock);
 510
 511         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 512
 513         if (conn)
 514                 rxrpc_disconnect_call(call);
 515
 516         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
 517                 rxrpc_free_skb(call->rxtx_buffer[i],
 518                                (call->tx_phase ? rxrpc_skb_tx_cleaned :
 519                                 rxrpc_skb_rx_cleaned));
 520                 call->rxtx_buffer[i] = NULL;
 521         }
 522
 523         _leave("");
 524 }
 525
 526 /*
 527  * Prepare a kernel service call for retry.
 528  */
 529 int rxrpc_prepare_call_for_retry(struct rxrpc_sock *rx, struct rxrpc_call *call)
 530 {
 531         const void *here = __builtin_return_address(0);
 532         int i;
 533         u8 last = 0;
 534
 535         _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
 536
 537         trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
 538                          here, (const void *)call->flags);
 539
 540         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 541         ASSERTCMP(call->completion, !=, RXRPC_CALL_REMOTELY_ABORTED);
 542         ASSERTCMP(call->completion, !=, RXRPC_CALL_LOCALLY_ABORTED);
 543         ASSERT(list_empty(&call->recvmsg_link));
 544
 545         del_timer_sync(&call->timer);
 546
 547         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, call->conn);
 548
 549         if (call->conn)
 550                 rxrpc_disconnect_call(call);
 551
 552         if (rxrpc_is_service_call(call) ||
 553             !call->tx_phase ||
 554             call->tx_hard_ack != 0 ||
 555             call->rx_hard_ack != 0 ||
 556             call->rx_top != 0)
 557                 return -EINVAL;
 558
 559         call->state = RXRPC_CALL_UNINITIALISED;
 560         call->completion = RXRPC_CALL_SUCCEEDED;
 561         call->call_id = 0;
 562         call->cid = 0;
 563         call->cong_cwnd = 0;
 564         call->cong_extra = 0;
 565         call->cong_ssthresh = 0;
 566         call->cong_mode = 0;
 567         call->cong_dup_acks = 0;
 568         call->cong_cumul_acks = 0;
 569         call->acks_lowest_nak = 0;
 570
 571         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
 572                 last |= call->rxtx_annotations[i];
 573                 call->rxtx_annotations[i] &= RXRPC_TX_ANNO_LAST;
 574                 call->rxtx_annotations[i] |= RXRPC_TX_ANNO_RETRANS;
 575         }
 576
 577         _leave(" = 0");
 578         return 0;
 579 }
 580
 581 /*
 582  * release all the calls associated with a socket
 583  */
 584 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 585 {
 586         struct rxrpc_call *call;
 587
 588         _enter("%p", rx);
 589
 590         while (!list_empty(&rx->to_be_accepted)) {
 591                 call = list_entry(rx->to_be_accepted.next,
 592                                   struct rxrpc_call, accept_link);
 593                 list_del(&call->accept_link);
 594                 rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
 595                 rxrpc_put_call(call, rxrpc_call_put);
 596         }
 597
 598         while (!list_empty(&rx->sock_calls)) {
 599                 call = list_entry(rx->sock_calls.next,
 600                                   struct rxrpc_call, sock_link);
 601                 rxrpc_get_call(call, rxrpc_call_got);
 602                 rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
 603                 rxrpc_send_abort_packet(call);
 604                 rxrpc_release_call(rx, call);
 605                 rxrpc_put_call(call, rxrpc_call_put);
 606         }
 607
 608         _leave("");
 609 }
 610
 611 /*
 612  * release a call
 613  */
 614 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 615 {
 616         struct rxrpc_net *rxnet;
 617         const void *here = __builtin_return_address(0);
 618         int n;
 619
 620         ASSERT(call != NULL);
 621
 622         n = atomic_dec_return(&call->usage);
 623         trace_rxrpc_call(call, op, n, here, NULL);
 624         ASSERTCMP(n, >=, 0);
 625         if (n == 0) {
 626                 _debug("call %d dead", call->debug_id);
 627                 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 628
 629                 if (!list_empty(&call->link)) {
 630                         rxnet = rxrpc_net(sock_net(&call->socket->sk));
 631                         write_lock(&rxnet->call_lock);
 632                         list_del_init(&call->link);
 633                         write_unlock(&rxnet->call_lock);
 634                 }
 635
 636                 rxrpc_cleanup_call(call);
 637         }
 638 }
 639
 640 /*
 641  * Final call destruction under RCU.
 642  */
 643 static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
 644 {
 645         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 646
 647         rxrpc_put_peer(call->peer);
 648         kfree(call->rxtx_buffer);
 649         kfree(call->rxtx_annotations);
 650         kmem_cache_free(rxrpc_call_jar, call);
 651 }
 652
 653 /*
 654  * clean up a call
 655  */
 656 void rxrpc_cleanup_call(struct rxrpc_call *call)
 657 {
 658         int i;
 659
 660         _net("DESTROY CALL %d", call->debug_id);
 661
 662         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 663
 664         del_timer_sync(&call->timer);
 665
 666         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 667         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 668         ASSERTCMP(call->conn, ==, NULL);
 669
 670         /* Clean up the Rx/Tx buffer */
 671         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
 672                 rxrpc_free_skb(call->rxtx_buffer[i],
 673                                (call->tx_phase ? rxrpc_skb_tx_cleaned :
 674                                 rxrpc_skb_rx_cleaned));
 675
 676         rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
 677
 678         call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
 679 }
 680
 681 /*
 682  * Make sure that all calls are gone from a network namespace.  To reach this
 683  * point, any open UDP sockets in that namespace must have been closed, so any
 684  * outstanding calls cannot be doing I/O.
 685  */
 686 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 687 {
 688         struct rxrpc_call *call;
 689
 690         _enter("");
 691
 692         if (list_empty(&rxnet->calls))
 693                 return;
 694
 695         write_lock(&rxnet->call_lock);
 696
 697         while (!list_empty(&rxnet->calls)) {
 698                 call = list_entry(rxnet->calls.next, struct rxrpc_call, link);
 699                 _debug("Zapping call %p", call);
 700
 701                 rxrpc_see_call(call);
 702                 list_del_init(&call->link);
 703
 704                 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 705                        call, atomic_read(&call->usage),
 706                        rxrpc_call_states[call->state],
 707                        call->flags, call->events);
 708
 709                 write_unlock(&rxnet->call_lock);
 710                 cond_resched();
 711                 write_lock(&rxnet->call_lock);
 712         }
 713
 714         write_unlock(&rxnet->call_lock);
 715 }