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_RECV_REQUEST]        = "SvRcvReq",
  27         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
  28         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
  29         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
  30         [RXRPC_CALL_COMPLETE]                   = "Complete",
  31 };
  32
  33 const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
  34         [RXRPC_CALL_SUCCEEDED]                  = "Complete",
  35         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
  36         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
  37         [RXRPC_CALL_LOCAL_ERROR]                = "LocError",
  38         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
  39 };
  40
  41 struct kmem_cache *rxrpc_call_jar;
  42
  43 static struct semaphore rxrpc_call_limiter =
  44         __SEMAPHORE_INITIALIZER(rxrpc_call_limiter, 1000);
  45 static struct semaphore rxrpc_kernel_call_limiter =
  46         __SEMAPHORE_INITIALIZER(rxrpc_kernel_call_limiter, 1000);
  47
  48 void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
  49 {
  50         struct rxrpc_local *local = call->local;
  51         bool busy;
  52
  53         if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
  54                 spin_lock_bh(&local->lock);
  55                 busy = !list_empty(&call->attend_link);
  56                 trace_rxrpc_poke_call(call, busy, what);
  57                 if (!busy) {
  58                         rxrpc_get_call(call, rxrpc_call_get_poke);
  59                         list_add_tail(&call->attend_link, &local->call_attend_q);
  60                 }
  61                 spin_unlock_bh(&local->lock);
  62                 rxrpc_wake_up_io_thread(local);
  63         }
  64 }
  65
  66 static void rxrpc_call_timer_expired(struct timer_list *t)
  67 {
  68         struct rxrpc_call *call = from_timer(call, t, timer);
  69
  70         _enter("%d", call->debug_id);
  71
  72         if (!__rxrpc_call_is_complete(call)) {
  73                 trace_rxrpc_timer_expired(call, jiffies);
  74                 rxrpc_poke_call(call, rxrpc_call_poke_timer);
  75         }
  76 }
  77
  78 void rxrpc_reduce_call_timer(struct rxrpc_call *call,
  79                              unsigned long expire_at,
  80                              unsigned long now,
  81                              enum rxrpc_timer_trace why)
  82 {
  83         trace_rxrpc_timer(call, why, now);
  84         timer_reduce(&call->timer, expire_at);
  85 }
  86
  87 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
  88
  89 static void rxrpc_destroy_call(struct work_struct *);
  90
  91 /*
  92  * find an extant server call
  93  * - called in process context with IRQs enabled
  94  */
  95 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
  96                                               unsigned long user_call_ID)
  97 {
  98         struct rxrpc_call *call;
  99         struct rb_node *p;
 100
 101         _enter("%p,%lx", rx, user_call_ID);
 102
 103         read_lock(&rx->call_lock);
 104
 105         p = rx->calls.rb_node;
 106         while (p) {
 107                 call = rb_entry(p, struct rxrpc_call, sock_node);
 108
 109                 if (user_call_ID < call->user_call_ID)
 110                         p = p->rb_left;
 111                 else if (user_call_ID > call->user_call_ID)
 112                         p = p->rb_right;
 113                 else
 114                         goto found_extant_call;
 115         }
 116
 117         read_unlock(&rx->call_lock);
 118         _leave(" = NULL");
 119         return NULL;
 120
 121 found_extant_call:
 122         rxrpc_get_call(call, rxrpc_call_get_sendmsg);
 123         read_unlock(&rx->call_lock);
 124         _leave(" = %p [%d]", call, refcount_read(&call->ref));
 125         return call;
 126 }
 127
 128 /*
 129  * allocate a new call
 130  */
 131 struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
 132                                     unsigned int debug_id)
 133 {
 134         struct rxrpc_call *call;
 135         struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
 136
 137         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 138         if (!call)
 139                 return NULL;
 140
 141         mutex_init(&call->user_mutex);
 142
 143         /* Prevent lockdep reporting a deadlock false positive between the afs
 144          * filesystem and sys_sendmsg() via the mmap sem.
 145          */
 146         if (rx->sk.sk_kern_sock)
 147                 lockdep_set_class(&call->user_mutex,
 148                                   &rxrpc_call_user_mutex_lock_class_key);
 149
 150         timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
 151         INIT_WORK(&call->destroyer, rxrpc_destroy_call);
 152         INIT_LIST_HEAD(&call->link);
 153         INIT_LIST_HEAD(&call->wait_link);
 154         INIT_LIST_HEAD(&call->accept_link);
 155         INIT_LIST_HEAD(&call->recvmsg_link);
 156         INIT_LIST_HEAD(&call->sock_link);
 157         INIT_LIST_HEAD(&call->attend_link);
 158         INIT_LIST_HEAD(&call->tx_sendmsg);
 159         INIT_LIST_HEAD(&call->tx_buffer);
 160         skb_queue_head_init(&call->recvmsg_queue);
 161         skb_queue_head_init(&call->rx_oos_queue);
 162         init_waitqueue_head(&call->waitq);
 163         spin_lock_init(&call->notify_lock);
 164         spin_lock_init(&call->tx_lock);
 165         refcount_set(&call->ref, 1);
 166         call->debug_id = debug_id;
 167         call->tx_total_len = -1;
 168         call->next_rx_timo = 20 * HZ;
 169         call->next_req_timo = 1 * HZ;
 170         call->ackr_window = 1;
 171         call->ackr_wtop = 1;
 172
 173         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 174
 175         call->rx_winsize = rxrpc_rx_window_size;
 176         call->tx_winsize = 16;
 177
 178         if (RXRPC_TX_SMSS > 2190)
 179                 call->cong_cwnd = 2;
 180         else if (RXRPC_TX_SMSS > 1095)
 181                 call->cong_cwnd = 3;
 182         else
 183                 call->cong_cwnd = 4;
 184         call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
 185
 186         call->rxnet = rxnet;
 187         call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
 188         atomic_inc(&rxnet->nr_calls);
 189         return call;
 190 }
 191
 192 /*
 193  * Allocate a new client call.
 194  */
 195 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 196                                                   struct sockaddr_rxrpc *srx,
 197                                                   struct rxrpc_conn_parameters *cp,
 198                                                   struct rxrpc_call_params *p,
 199                                                   gfp_t gfp,
 200                                                   unsigned int debug_id)
 201 {
 202         struct rxrpc_call *call;
 203         ktime_t now;
 204         int ret;
 205
 206         _enter("");
 207
 208         call = rxrpc_alloc_call(rx, gfp, debug_id);
 209         if (!call)
 210                 return ERR_PTR(-ENOMEM);
 211         now = ktime_get_real();
 212         call->acks_latest_ts    = now;
 213         call->cong_tstamp       = now;
 214         call->dest_srx          = *srx;
 215         call->interruptibility  = p->interruptibility;
 216         call->tx_total_len      = p->tx_total_len;
 217         call->key               = key_get(cp->key);
 218         call->local             = rxrpc_get_local(cp->local, rxrpc_local_get_call);
 219         call->security_level    = cp->security_level;
 220         if (p->kernel)
 221                 __set_bit(RXRPC_CALL_KERNEL, &call->flags);
 222         if (cp->upgrade)
 223                 __set_bit(RXRPC_CALL_UPGRADE, &call->flags);
 224         if (cp->exclusive)
 225                 __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
 226
 227         ret = rxrpc_init_client_call_security(call);
 228         if (ret < 0) {
 229                 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
 230                 rxrpc_put_call(call, rxrpc_call_put_discard_error);
 231                 return ERR_PTR(ret);
 232         }
 233
 234         rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
 235
 236         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
 237                          p->user_call_ID, rxrpc_call_new_client);
 238
 239         _leave(" = %p", call);
 240         return call;
 241 }
 242
 243 /*
 244  * Initiate the call ack/resend/expiry timer.
 245  */
 246 void rxrpc_start_call_timer(struct rxrpc_call *call)
 247 {
 248         unsigned long now = jiffies;
 249         unsigned long j = now + MAX_JIFFY_OFFSET;
 250
 251         call->delay_ack_at = j;
 252         call->ack_lost_at = j;
 253         call->resend_at = j;
 254         call->ping_at = j;
 255         call->keepalive_at = j;
 256         call->expect_rx_by = j;
 257         call->expect_req_by = j;
 258         call->expect_term_by = j;
 259         call->timer.expires = now;
 260 }
 261
 262 /*
 263  * Wait for a call slot to become available.
 264  */
 265 static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
 266 {
 267         struct semaphore *limiter = &rxrpc_call_limiter;
 268
 269         if (p->kernel)
 270                 limiter = &rxrpc_kernel_call_limiter;
 271         if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
 272                 down(limiter);
 273                 return limiter;
 274         }
 275         return down_interruptible(limiter) < 0 ? NULL : limiter;
 276 }
 277
 278 /*
 279  * Release a call slot.
 280  */
 281 static void rxrpc_put_call_slot(struct rxrpc_call *call)
 282 {
 283         struct semaphore *limiter = &rxrpc_call_limiter;
 284
 285         if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
 286                 limiter = &rxrpc_kernel_call_limiter;
 287         up(limiter);
 288 }
 289
 290 /*
 291  * Start the process of connecting a call.  We obtain a peer and a connection
 292  * bundle, but the actual association of a call with a connection is offloaded
 293  * to the I/O thread to simplify locking.
 294  */
 295 static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
 296 {
 297         struct rxrpc_local *local = call->local;
 298         int ret = -ENOMEM;
 299
 300         _enter("{%d,%lx},", call->debug_id, call->user_call_ID);
 301
 302         call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp);
 303         if (!call->peer)
 304                 goto error;
 305
 306         ret = rxrpc_look_up_bundle(call, gfp);
 307         if (ret < 0)
 308                 goto error;
 309
 310         trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
 311         rxrpc_get_call(call, rxrpc_call_get_io_thread);
 312         spin_lock(&local->client_call_lock);
 313         list_add_tail(&call->wait_link, &local->new_client_calls);
 314         spin_unlock(&local->client_call_lock);
 315         rxrpc_wake_up_io_thread(local);
 316         return 0;
 317
 318 error:
 319         __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
 320         return ret;
 321 }
 322
 323 /*
 324  * Set up a call for the given parameters.
 325  * - Called with the socket lock held, which it must release.
 326  * - If it returns a call, the call's lock will need releasing by the caller.
 327  */
 328 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 329                                          struct rxrpc_conn_parameters *cp,
 330                                          struct sockaddr_rxrpc *srx,
 331                                          struct rxrpc_call_params *p,
 332                                          gfp_t gfp,
 333                                          unsigned int debug_id)
 334         __releases(&rx->sk.sk_lock.slock)
 335         __acquires(&call->user_mutex)
 336 {
 337         struct rxrpc_call *call, *xcall;
 338         struct rxrpc_net *rxnet;
 339         struct semaphore *limiter;
 340         struct rb_node *parent, **pp;
 341         int ret;
 342
 343         _enter("%p,%lx", rx, p->user_call_ID);
 344
 345         limiter = rxrpc_get_call_slot(p, gfp);
 346         if (!limiter) {
 347                 release_sock(&rx->sk);
 348                 return ERR_PTR(-ERESTARTSYS);
 349         }
 350
 351         call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id);
 352         if (IS_ERR(call)) {
 353                 release_sock(&rx->sk);
 354                 up(limiter);
 355                 _leave(" = %ld", PTR_ERR(call));
 356                 return call;
 357         }
 358
 359         /* We need to protect a partially set up call against the user as we
 360          * will be acting outside the socket lock.
 361          */
 362         mutex_lock(&call->user_mutex);
 363
 364         /* Publish the call, even though it is incompletely set up as yet */
 365         write_lock(&rx->call_lock);
 366
 367         pp = &rx->calls.rb_node;
 368         parent = NULL;
 369         while (*pp) {
 370                 parent = *pp;
 371                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 372
 373                 if (p->user_call_ID < xcall->user_call_ID)
 374                         pp = &(*pp)->rb_left;
 375                 else if (p->user_call_ID > xcall->user_call_ID)
 376                         pp = &(*pp)->rb_right;
 377                 else
 378                         goto error_dup_user_ID;
 379         }
 380
 381         rcu_assign_pointer(call->socket, rx);
 382         call->user_call_ID = p->user_call_ID;
 383         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 384         rxrpc_get_call(call, rxrpc_call_get_userid);
 385         rb_link_node(&call->sock_node, parent, pp);
 386         rb_insert_color(&call->sock_node, &rx->calls);
 387         list_add(&call->sock_link, &rx->sock_calls);
 388
 389         write_unlock(&rx->call_lock);
 390
 391         rxnet = call->rxnet;
 392         spin_lock(&rxnet->call_lock);
 393         list_add_tail_rcu(&call->link, &rxnet->calls);
 394         spin_unlock(&rxnet->call_lock);
 395
 396         /* From this point on, the call is protected by its own lock. */
 397         release_sock(&rx->sk);
 398
 399         /* Set up or get a connection record and set the protocol parameters,
 400          * including channel number and call ID.
 401          */
 402         ret = rxrpc_connect_call(call, gfp);
 403         if (ret < 0)
 404                 goto error_attached_to_socket;
 405
 406         _leave(" = %p [new]", call);
 407         return call;
 408
 409         /* We unexpectedly found the user ID in the list after taking
 410          * the call_lock.  This shouldn't happen unless the user races
 411          * with itself and tries to add the same user ID twice at the
 412          * same time in different threads.
 413          */
 414 error_dup_user_ID:
 415         write_unlock(&rx->call_lock);
 416         release_sock(&rx->sk);
 417         rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
 418         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
 419                          rxrpc_call_see_userid_exists);
 420         mutex_unlock(&call->user_mutex);
 421         rxrpc_put_call(call, rxrpc_call_put_userid_exists);
 422         _leave(" = -EEXIST");
 423         return ERR_PTR(-EEXIST);
 424
 425         /* We got an error, but the call is attached to the socket and is in
 426          * need of release.  However, we might now race with recvmsg() when it
 427          * completion notifies the socket.  Return 0 from sys_sendmsg() and
 428          * leave the error to recvmsg() to deal with.
 429          */
 430 error_attached_to_socket:
 431         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
 432                          rxrpc_call_see_connect_failed);
 433         rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
 434         _leave(" = c=%08x [err]", call->debug_id);
 435         return call;
 436 }
 437
 438 /*
 439  * Set up an incoming call.  call->conn points to the connection.
 440  * This is called in BH context and isn't allowed to fail.
 441  */
 442 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 443                          struct rxrpc_call *call,
 444                          struct sk_buff *skb)
 445 {
 446         struct rxrpc_connection *conn = call->conn;
 447         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 448         u32 chan;
 449
 450         _enter(",%d", call->conn->debug_id);
 451
 452         rcu_assign_pointer(call->socket, rx);
 453         call->call_id           = sp->hdr.callNumber;
 454         call->dest_srx.srx_service = sp->hdr.serviceId;
 455         call->cid               = sp->hdr.cid;
 456         call->cong_tstamp       = skb->tstamp;
 457
 458         __set_bit(RXRPC_CALL_EXPOSED, &call->flags);
 459         rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
 460
 461         spin_lock(&conn->state_lock);
 462
 463         switch (conn->state) {
 464         case RXRPC_CONN_SERVICE_UNSECURED:
 465         case RXRPC_CONN_SERVICE_CHALLENGING:
 466                 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
 467                 break;
 468         case RXRPC_CONN_SERVICE:
 469                 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
 470                 break;
 471
 472         case RXRPC_CONN_ABORTED:
 473                 rxrpc_set_call_completion(call, conn->completion,
 474                                           conn->abort_code, conn->error);
 475                 break;
 476         default:
 477                 BUG();
 478         }
 479
 480         rxrpc_get_call(call, rxrpc_call_get_io_thread);
 481
 482         /* Set the channel for this call.  We don't get channel_lock as we're
 483          * only defending against the data_ready handler (which we're called
 484          * from) and the RESPONSE packet parser (which is only really
 485          * interested in call_counter and can cope with a disagreement with the
 486          * call pointer).
 487          */
 488         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 489         conn->channels[chan].call_counter = call->call_id;
 490         conn->channels[chan].call_id = call->call_id;
 491         conn->channels[chan].call = call;
 492         spin_unlock(&conn->state_lock);
 493
 494         spin_lock(&conn->peer->lock);
 495         hlist_add_head(&call->error_link, &conn->peer->error_targets);
 496         spin_unlock(&conn->peer->lock);
 497
 498         rxrpc_start_call_timer(call);
 499         _leave("");
 500 }
 501
 502 /*
 503  * Note the re-emergence of a call.
 504  */
 505 void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 506 {
 507         if (call) {
 508                 int r = refcount_read(&call->ref);
 509
 510                 trace_rxrpc_call(call->debug_id, r, 0, why);
 511         }
 512 }
 513
 514 struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
 515                                       enum rxrpc_call_trace why)
 516 {
 517         int r;
 518
 519         if (!call || !__refcount_inc_not_zero(&call->ref, &r))
 520                 return NULL;
 521         trace_rxrpc_call(call->debug_id, r + 1, 0, why);
 522         return call;
 523 }
 524
 525 /*
 526  * Note the addition of a ref on a call.
 527  */
 528 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 529 {
 530         int r;
 531
 532         __refcount_inc(&call->ref, &r);
 533         trace_rxrpc_call(call->debug_id, r + 1, 0, why);
 534 }
 535
 536 /*
 537  * Clean up the Rx skb ring.
 538  */
 539 static void rxrpc_cleanup_ring(struct rxrpc_call *call)
 540 {
 541         skb_queue_purge(&call->recvmsg_queue);
 542         skb_queue_purge(&call->rx_oos_queue);
 543 }
 544
 545 /*
 546  * Detach a call from its owning socket.
 547  */
 548 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 549 {
 550         struct rxrpc_connection *conn = call->conn;
 551         bool put = false, putu = false;
 552
 553         _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
 554
 555         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
 556                          call->flags, rxrpc_call_see_release);
 557
 558         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 559                 BUG();
 560
 561         rxrpc_put_call_slot(call);
 562
 563         /* Make sure we don't get any more notifications */
 564         spin_lock(&rx->recvmsg_lock);
 565
 566         if (!list_empty(&call->recvmsg_link)) {
 567                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 568                        call, call->events, call->flags);
 569                 list_del(&call->recvmsg_link);
 570                 put = true;
 571         }
 572
 573         /* list_empty() must return false in rxrpc_notify_socket() */
 574         call->recvmsg_link.next = NULL;
 575         call->recvmsg_link.prev = NULL;
 576
 577         spin_unlock(&rx->recvmsg_lock);
 578         if (put)
 579                 rxrpc_put_call(call, rxrpc_call_put_unnotify);
 580
 581         write_lock(&rx->call_lock);
 582
 583         if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 584                 rb_erase(&call->sock_node, &rx->calls);
 585                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 586                 putu = true;
 587         }
 588
 589         list_del(&call->sock_link);
 590         write_unlock(&rx->call_lock);
 591
 592         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 593
 594         if (putu)
 595                 rxrpc_put_call(call, rxrpc_call_put_userid);
 596
 597         _leave("");
 598 }
 599
 600 /*
 601  * release all the calls associated with a socket
 602  */
 603 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 604 {
 605         struct rxrpc_call *call;
 606
 607         _enter("%p", rx);
 608
 609         while (!list_empty(&rx->to_be_accepted)) {
 610                 call = list_entry(rx->to_be_accepted.next,
 611                                   struct rxrpc_call, accept_link);
 612                 list_del(&call->accept_link);
 613                 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
 614                                     rxrpc_abort_call_sock_release_tba);
 615                 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
 616         }
 617
 618         while (!list_empty(&rx->sock_calls)) {
 619                 call = list_entry(rx->sock_calls.next,
 620                                   struct rxrpc_call, sock_link);
 621                 rxrpc_get_call(call, rxrpc_call_get_release_sock);
 622                 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
 623                                     rxrpc_abort_call_sock_release);
 624                 rxrpc_release_call(rx, call);
 625                 rxrpc_put_call(call, rxrpc_call_put_release_sock);
 626         }
 627
 628         _leave("");
 629 }
 630
 631 /*
 632  * release a call
 633  */
 634 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 635 {
 636         struct rxrpc_net *rxnet = call->rxnet;
 637         unsigned int debug_id = call->debug_id;
 638         bool dead;
 639         int r;
 640
 641         ASSERT(call != NULL);
 642
 643         dead = __refcount_dec_and_test(&call->ref, &r);
 644         trace_rxrpc_call(debug_id, r - 1, 0, why);
 645         if (dead) {
 646                 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 647
 648                 if (!list_empty(&call->link)) {
 649                         spin_lock(&rxnet->call_lock);
 650                         list_del_init(&call->link);
 651                         spin_unlock(&rxnet->call_lock);
 652                 }
 653
 654                 rxrpc_cleanup_call(call);
 655         }
 656 }
 657
 658 /*
 659  * Free up the call under RCU.
 660  */
 661 static void rxrpc_rcu_free_call(struct rcu_head *rcu)
 662 {
 663         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 664         struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
 665
 666         kmem_cache_free(rxrpc_call_jar, call);
 667         if (atomic_dec_and_test(&rxnet->nr_calls))
 668                 wake_up_var(&rxnet->nr_calls);
 669 }
 670
 671 /*
 672  * Final call destruction - but must be done in process context.
 673  */
 674 static void rxrpc_destroy_call(struct work_struct *work)
 675 {
 676         struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
 677         struct rxrpc_txbuf *txb;
 678
 679         del_timer_sync(&call->timer);
 680
 681         rxrpc_cleanup_ring(call);
 682         while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
 683                                                struct rxrpc_txbuf, call_link))) {
 684                 list_del(&txb->call_link);
 685                 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
 686         }
 687         while ((txb = list_first_entry_or_null(&call->tx_buffer,
 688                                                struct rxrpc_txbuf, call_link))) {
 689                 list_del(&txb->call_link);
 690                 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
 691         }
 692
 693         rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
 694         rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
 695         rxrpc_deactivate_bundle(call->bundle);
 696         rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
 697         rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
 698         rxrpc_put_local(call->local, rxrpc_local_put_call);
 699         call_rcu(&call->rcu, rxrpc_rcu_free_call);
 700 }
 701
 702 /*
 703  * clean up a call
 704  */
 705 void rxrpc_cleanup_call(struct rxrpc_call *call)
 706 {
 707         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 708
 709         ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 710         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 711
 712         del_timer(&call->timer);
 713
 714         if (rcu_read_lock_held())
 715                 /* Can't use the rxrpc workqueue as we need to cancel/flush
 716                  * something that may be running/waiting there.
 717                  */
 718                 schedule_work(&call->destroyer);
 719         else
 720                 rxrpc_destroy_call(&call->destroyer);
 721 }
 722
 723 /*
 724  * Make sure that all calls are gone from a network namespace.  To reach this
 725  * point, any open UDP sockets in that namespace must have been closed, so any
 726  * outstanding calls cannot be doing I/O.
 727  */
 728 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 729 {
 730         struct rxrpc_call *call;
 731
 732         _enter("");
 733
 734         if (!list_empty(&rxnet->calls)) {
 735                 spin_lock(&rxnet->call_lock);
 736
 737                 while (!list_empty(&rxnet->calls)) {
 738                         call = list_entry(rxnet->calls.next,
 739                                           struct rxrpc_call, link);
 740                         _debug("Zapping call %p", call);
 741
 742                         rxrpc_see_call(call, rxrpc_call_see_zap);
 743                         list_del_init(&call->link);
 744
 745                         pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 746                                call, refcount_read(&call->ref),
 747                                rxrpc_call_states[__rxrpc_call_state(call)],
 748                                call->flags, call->events);
 749
 750                         spin_unlock(&rxnet->call_lock);
 751                         cond_resched();
 752                         spin_lock(&rxnet->call_lock);
 753                 }
 754
 755                 spin_unlock(&rxnet->call_lock);
 756         }
 757
 758         atomic_dec(&rxnet->nr_calls);
 759         wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 760 }