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                                     unsigned int debug_id)
 104 {
 105         struct rxrpc_call *call;
 106         struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
 107
 108         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 109         if (!call)
 110                 return NULL;
 111
 112         call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
 113                                     sizeof(struct sk_buff *),
 114                                     gfp);
 115         if (!call->rxtx_buffer)
 116                 goto nomem;
 117
 118         call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
 119         if (!call->rxtx_annotations)
 120                 goto nomem_2;
 121
 122         mutex_init(&call->user_mutex);
 123
 124         /* Prevent lockdep reporting a deadlock false positive between the afs
 125          * filesystem and sys_sendmsg() via the mmap sem.
 126          */
 127         if (rx->sk.sk_kern_sock)
 128                 lockdep_set_class(&call->user_mutex,
 129                                   &rxrpc_call_user_mutex_lock_class_key);
 130
 131         timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
 132         INIT_WORK(&call->processor, &rxrpc_process_call);
 133         INIT_LIST_HEAD(&call->link);
 134         INIT_LIST_HEAD(&call->chan_wait_link);
 135         INIT_LIST_HEAD(&call->accept_link);
 136         INIT_LIST_HEAD(&call->recvmsg_link);
 137         INIT_LIST_HEAD(&call->sock_link);
 138         init_waitqueue_head(&call->waitq);
 139         spin_lock_init(&call->lock);
 140         spin_lock_init(&call->notify_lock);
 141         rwlock_init(&call->state_lock);
 142         atomic_set(&call->usage, 1);
 143         call->debug_id = debug_id;
 144         call->tx_total_len = -1;
 145         call->next_rx_timo = 20 * HZ;
 146         call->next_req_timo = 1 * HZ;
 147
 148         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 149
 150         /* Leave space in the ring to handle a maxed-out jumbo packet */
 151         call->rx_winsize = rxrpc_rx_window_size;
 152         call->tx_winsize = 16;
 153         call->rx_expect_next = 1;
 154
 155         call->cong_cwnd = 2;
 156         call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
 157
 158         call->rxnet = rxnet;
 159         atomic_inc(&rxnet->nr_calls);
 160         return call;
 161
 162 nomem_2:
 163         kfree(call->rxtx_buffer);
 164 nomem:
 165         kmem_cache_free(rxrpc_call_jar, call);
 166         return NULL;
 167 }
 168
 169 /*
 170  * Allocate a new client call.
 171  */
 172 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 173                                                   struct sockaddr_rxrpc *srx,
 174                                                   gfp_t gfp,
 175                                                   unsigned int debug_id)
 176 {
 177         struct rxrpc_call *call;
 178         ktime_t now;
 179
 180         _enter("");
 181
 182         call = rxrpc_alloc_call(rx, gfp, debug_id);
 183         if (!call)
 184                 return ERR_PTR(-ENOMEM);
 185         call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
 186         call->service_id = srx->srx_service;
 187         call->tx_phase = true;
 188         now = ktime_get_real();
 189         call->acks_latest_ts = now;
 190         call->cong_tstamp = now;
 191
 192         _leave(" = %p", call);
 193         return call;
 194 }
 195
 196 /*
 197  * Initiate the call ack/resend/expiry timer.
 198  */
 199 static void rxrpc_start_call_timer(struct rxrpc_call *call)
 200 {
 201         unsigned long now = jiffies;
 202         unsigned long j = now + MAX_JIFFY_OFFSET;
 203
 204         call->ack_at = j;
 205         call->ack_lost_at = j;
 206         call->resend_at = j;
 207         call->ping_at = j;
 208         call->expect_rx_by = j;
 209         call->expect_req_by = j;
 210         call->expect_term_by = j;
 211         call->timer.expires = now;
 212 }
 213
 214 /*
 215  * Set up a call for the given parameters.
 216  * - Called with the socket lock held, which it must release.
 217  * - If it returns a call, the call's lock will need releasing by the caller.
 218  */
 219 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 220                                          struct rxrpc_conn_parameters *cp,
 221                                          struct sockaddr_rxrpc *srx,
 222                                          struct rxrpc_call_params *p,
 223                                          gfp_t gfp,
 224                                          unsigned int debug_id)
 225         __releases(&rx->sk.sk_lock.slock)
 226         __acquires(&call->user_mutex)
 227 {
 228         struct rxrpc_call *call, *xcall;
 229         struct rxrpc_net *rxnet;
 230         struct rb_node *parent, **pp;
 231         const void *here = __builtin_return_address(0);
 232         int ret;
 233
 234         _enter("%p,%lx", rx, p->user_call_ID);
 235
 236         call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
 237         if (IS_ERR(call)) {
 238                 release_sock(&rx->sk);
 239                 _leave(" = %ld", PTR_ERR(call));
 240                 return call;
 241         }
 242
 243         call->tx_total_len = p->tx_total_len;
 244         trace_rxrpc_call(call, rxrpc_call_new_client, 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(call, cp, srx, gfp);
 291         if (ret < 0)
 292                 goto error;
 293
 294         trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
 295                          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, rxrpc_call_error, atomic_read(&call->usage),
 318                          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  * Retry a call to a new address.  It is expected that the Tx queue of the call
 328  * will contain data previously packaged for an old call.
 329  */
 330 int rxrpc_retry_client_call(struct rxrpc_sock *rx,
 331                             struct rxrpc_call *call,
 332                             struct rxrpc_conn_parameters *cp,
 333                             struct sockaddr_rxrpc *srx,
 334                             gfp_t gfp)
 335 {
 336         const void *here = __builtin_return_address(0);
 337         int ret;
 338
 339         /* Set up or get a connection record and set the protocol parameters,
 340          * including channel number and call ID.
 341          */
 342         ret = rxrpc_connect_call(call, cp, srx, gfp);
 343         if (ret < 0)
 344                 goto error;
 345
 346         trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
 347                          here, NULL);
 348
 349         rxrpc_start_call_timer(call);
 350
 351         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 352
 353         if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 354                 rxrpc_queue_call(call);
 355
 356         _leave(" = 0");
 357         return 0;
 358
 359 error:
 360         rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 361                                   RX_CALL_DEAD, ret);
 362         trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
 363                          here, ERR_PTR(ret));
 364         _leave(" = %d", ret);
 365         return ret;
 366 }
 367
 368 /*
 369  * Set up an incoming call.  call->conn points to the connection.
 370  * This is called in BH context and isn't allowed to fail.
 371  */
 372 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 373                          struct rxrpc_call *call,
 374                          struct sk_buff *skb)
 375 {
 376         struct rxrpc_connection *conn = call->conn;
 377         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 378         u32 chan;
 379
 380         _enter(",%d", call->conn->debug_id);
 381
 382         rcu_assign_pointer(call->socket, rx);
 383         call->call_id           = sp->hdr.callNumber;
 384         call->service_id        = sp->hdr.serviceId;
 385         call->cid               = sp->hdr.cid;
 386         call->state             = RXRPC_CALL_SERVER_ACCEPTING;
 387         if (sp->hdr.securityIndex > 0)
 388                 call->state     = RXRPC_CALL_SERVER_SECURING;
 389         call->cong_tstamp       = skb->tstamp;
 390
 391         /* Set the channel for this call.  We don't get channel_lock as we're
 392          * only defending against the data_ready handler (which we're called
 393          * from) and the RESPONSE packet parser (which is only really
 394          * interested in call_counter and can cope with a disagreement with the
 395          * call pointer).
 396          */
 397         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 398         conn->channels[chan].call_counter = call->call_id;
 399         conn->channels[chan].call_id = call->call_id;
 400         rcu_assign_pointer(conn->channels[chan].call, call);
 401
 402         spin_lock(&conn->params.peer->lock);
 403         hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
 404         spin_unlock(&conn->params.peer->lock);
 405
 406         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 407
 408         rxrpc_start_call_timer(call);
 409         _leave("");
 410 }
 411
 412 /*
 413  * Queue a call's work processor, getting a ref to pass to the work queue.
 414  */
 415 bool rxrpc_queue_call(struct rxrpc_call *call)
 416 {
 417         const void *here = __builtin_return_address(0);
 418         int n = __atomic_add_unless(&call->usage, 1, 0);
 419         if (n == 0)
 420                 return false;
 421         if (rxrpc_queue_work(&call->processor))
 422                 trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
 423         else
 424                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 425         return true;
 426 }
 427
 428 /*
 429  * Queue a call's work processor, passing the callers ref to the work queue.
 430  */
 431 bool __rxrpc_queue_call(struct rxrpc_call *call)
 432 {
 433         const void *here = __builtin_return_address(0);
 434         int n = atomic_read(&call->usage);
 435         ASSERTCMP(n, >=, 1);
 436         if (rxrpc_queue_work(&call->processor))
 437                 trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
 438         else
 439                 rxrpc_put_call(call, rxrpc_call_put_noqueue);
 440         return true;
 441 }
 442
 443 /*
 444  * Note the re-emergence of a call.
 445  */
 446 void rxrpc_see_call(struct rxrpc_call *call)
 447 {
 448         const void *here = __builtin_return_address(0);
 449         if (call) {
 450                 int n = atomic_read(&call->usage);
 451
 452                 trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
 453         }
 454 }
 455
 456 /*
 457  * Note the addition of a ref on a call.
 458  */
 459 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 460 {
 461         const void *here = __builtin_return_address(0);
 462         int n = atomic_inc_return(&call->usage);
 463
 464         trace_rxrpc_call(call, op, n, here, NULL);
 465 }
 466
 467 /*
 468  * Detach a call from its owning socket.
 469  */
 470 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 471 {
 472         const void *here = __builtin_return_address(0);
 473         struct rxrpc_connection *conn = call->conn;
 474         bool put = false;
 475         int i;
 476
 477         _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
 478
 479         trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
 480                          here, (const void *)call->flags);
 481
 482         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 483
 484         spin_lock_bh(&call->lock);
 485         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 486                 BUG();
 487         spin_unlock_bh(&call->lock);
 488
 489         del_timer_sync(&call->timer);
 490
 491         /* Make sure we don't get any more notifications */
 492         write_lock_bh(&rx->recvmsg_lock);
 493
 494         if (!list_empty(&call->recvmsg_link)) {
 495                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 496                        call, call->events, call->flags);
 497                 list_del(&call->recvmsg_link);
 498                 put = true;
 499         }
 500
 501         /* list_empty() must return false in rxrpc_notify_socket() */
 502         call->recvmsg_link.next = NULL;
 503         call->recvmsg_link.prev = NULL;
 504
 505         write_unlock_bh(&rx->recvmsg_lock);
 506         if (put)
 507                 rxrpc_put_call(call, rxrpc_call_put);
 508
 509         write_lock(&rx->call_lock);
 510
 511         if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 512                 rb_erase(&call->sock_node, &rx->calls);
 513                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 514                 rxrpc_put_call(call, rxrpc_call_put_userid);
 515         }
 516
 517         list_del(&call->sock_link);
 518         write_unlock(&rx->call_lock);
 519
 520         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 521
 522         if (conn)
 523                 rxrpc_disconnect_call(call);
 524
 525         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
 526                 rxrpc_free_skb(call->rxtx_buffer[i],
 527                                (call->tx_phase ? rxrpc_skb_tx_cleaned :
 528                                 rxrpc_skb_rx_cleaned));
 529                 call->rxtx_buffer[i] = NULL;
 530         }
 531
 532         _leave("");
 533 }
 534
 535 /*
 536  * Prepare a kernel service call for retry.
 537  */
 538 int rxrpc_prepare_call_for_retry(struct rxrpc_sock *rx, struct rxrpc_call *call)
 539 {
 540         const void *here = __builtin_return_address(0);
 541         int i;
 542         u8 last = 0;
 543
 544         _enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
 545
 546         trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
 547                          here, (const void *)call->flags);
 548
 549         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 550         ASSERTCMP(call->completion, !=, RXRPC_CALL_REMOTELY_ABORTED);
 551         ASSERTCMP(call->completion, !=, RXRPC_CALL_LOCALLY_ABORTED);
 552         ASSERT(list_empty(&call->recvmsg_link));
 553
 554         del_timer_sync(&call->timer);
 555
 556         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, call->conn);
 557
 558         if (call->conn)
 559                 rxrpc_disconnect_call(call);
 560
 561         if (rxrpc_is_service_call(call) ||
 562             !call->tx_phase ||
 563             call->tx_hard_ack != 0 ||
 564             call->rx_hard_ack != 0 ||
 565             call->rx_top != 0)
 566                 return -EINVAL;
 567
 568         call->state = RXRPC_CALL_UNINITIALISED;
 569         call->completion = RXRPC_CALL_SUCCEEDED;
 570         call->call_id = 0;
 571         call->cid = 0;
 572         call->cong_cwnd = 0;
 573         call->cong_extra = 0;
 574         call->cong_ssthresh = 0;
 575         call->cong_mode = 0;
 576         call->cong_dup_acks = 0;
 577         call->cong_cumul_acks = 0;
 578         call->acks_lowest_nak = 0;
 579
 580         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
 581                 last |= call->rxtx_annotations[i];
 582                 call->rxtx_annotations[i] &= RXRPC_TX_ANNO_LAST;
 583                 call->rxtx_annotations[i] |= RXRPC_TX_ANNO_RETRANS;
 584         }
 585
 586         _leave(" = 0");
 587         return 0;
 588 }
 589
 590 /*
 591  * release all the calls associated with a socket
 592  */
 593 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 594 {
 595         struct rxrpc_call *call;
 596
 597         _enter("%p", rx);
 598
 599         while (!list_empty(&rx->to_be_accepted)) {
 600                 call = list_entry(rx->to_be_accepted.next,
 601                                   struct rxrpc_call, accept_link);
 602                 list_del(&call->accept_link);
 603                 rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
 604                 rxrpc_put_call(call, rxrpc_call_put);
 605         }
 606
 607         while (!list_empty(&rx->sock_calls)) {
 608                 call = list_entry(rx->sock_calls.next,
 609                                   struct rxrpc_call, sock_link);
 610                 rxrpc_get_call(call, rxrpc_call_got);
 611                 rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
 612                 rxrpc_send_abort_packet(call);
 613                 rxrpc_release_call(rx, call);
 614                 rxrpc_put_call(call, rxrpc_call_put);
 615         }
 616
 617         _leave("");
 618 }
 619
 620 /*
 621  * release a call
 622  */
 623 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 624 {
 625         struct rxrpc_net *rxnet = call->rxnet;
 626         const void *here = __builtin_return_address(0);
 627         int n;
 628
 629         ASSERT(call != NULL);
 630
 631         n = atomic_dec_return(&call->usage);
 632         trace_rxrpc_call(call, op, n, here, NULL);
 633         ASSERTCMP(n, >=, 0);
 634         if (n == 0) {
 635                 _debug("call %d dead", call->debug_id);
 636                 ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 637
 638                 if (!list_empty(&call->link)) {
 639                         write_lock(&rxnet->call_lock);
 640                         list_del_init(&call->link);
 641                         write_unlock(&rxnet->call_lock);
 642                 }
 643
 644                 rxrpc_cleanup_call(call);
 645         }
 646 }
 647
 648 /*
 649  * Final call destruction under RCU.
 650  */
 651 static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
 652 {
 653         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 654         struct rxrpc_net *rxnet = call->rxnet;
 655
 656         rxrpc_put_peer(call->peer);
 657         kfree(call->rxtx_buffer);
 658         kfree(call->rxtx_annotations);
 659         kmem_cache_free(rxrpc_call_jar, call);
 660         if (atomic_dec_and_test(&rxnet->nr_calls))
 661                 wake_up_var(&rxnet->nr_calls);
 662 }
 663
 664 /*
 665  * clean up a call
 666  */
 667 void rxrpc_cleanup_call(struct rxrpc_call *call)
 668 {
 669         int i;
 670
 671         _net("DESTROY CALL %d", call->debug_id);
 672
 673         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 674
 675         del_timer_sync(&call->timer);
 676
 677         ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
 678         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 679         ASSERTCMP(call->conn, ==, NULL);
 680
 681         /* Clean up the Rx/Tx buffer */
 682         for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
 683                 rxrpc_free_skb(call->rxtx_buffer[i],
 684                                (call->tx_phase ? rxrpc_skb_tx_cleaned :
 685                                 rxrpc_skb_rx_cleaned));
 686
 687         rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
 688
 689         call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
 690 }
 691
 692 /*
 693  * Make sure that all calls are gone from a network namespace.  To reach this
 694  * point, any open UDP sockets in that namespace must have been closed, so any
 695  * outstanding calls cannot be doing I/O.
 696  */
 697 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 698 {
 699         struct rxrpc_call *call;
 700
 701         _enter("");
 702
 703         if (list_empty(&rxnet->calls))
 704                 return;
 705
 706         write_lock(&rxnet->call_lock);
 707
 708         while (!list_empty(&rxnet->calls)) {
 709                 call = list_entry(rxnet->calls.next, struct rxrpc_call, link);
 710                 _debug("Zapping call %p", call);
 711
 712                 rxrpc_see_call(call);
 713                 list_del_init(&call->link);
 714
 715                 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 716                        call, atomic_read(&call->usage),
 717                        rxrpc_call_states[call->state],
 718                        call->flags, call->events);
 719
 720                 write_unlock(&rxnet->call_lock);
 721                 cond_resched();
 722                 write_lock(&rxnet->call_lock);
 723         }
 724
 725         write_unlock(&rxnet->call_lock);
 726
 727         atomic_dec(&rxnet->nr_calls);
 728         wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 729 }