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         atomic64_set(&call->ackr_window, 0x100000001ULL);
 171
 172         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 173
 174         call->rx_winsize = rxrpc_rx_window_size;
 175         call->tx_winsize = 16;
 176
 177         if (RXRPC_TX_SMSS > 2190)
 178                 call->cong_cwnd = 2;
 179         else if (RXRPC_TX_SMSS > 1095)
 180                 call->cong_cwnd = 3;
 181         else
 182                 call->cong_cwnd = 4;
 183         call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
 184
 185         call->rxnet = rxnet;
 186         call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
 187         atomic_inc(&rxnet->nr_calls);
 188         return call;
 189 }
 190
 191 /*
 192  * Allocate a new client call.
 193  */
 194 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 195                                                   struct sockaddr_rxrpc *srx,
 196                                                   struct rxrpc_conn_parameters *cp,
 197                                                   struct rxrpc_call_params *p,
 198                                                   gfp_t gfp,
 199                                                   unsigned int debug_id)
 200 {
 201         struct rxrpc_call *call;
 202         ktime_t now;
 203         int ret;
 204
 205         _enter("");
 206
 207         call = rxrpc_alloc_call(rx, gfp, debug_id);
 208         if (!call)
 209                 return ERR_PTR(-ENOMEM);
 210         now = ktime_get_real();
 211         call->acks_latest_ts    = now;
 212         call->cong_tstamp       = now;
 213         call->dest_srx          = *srx;
 214         call->interruptibility  = p->interruptibility;
 215         call->tx_total_len      = p->tx_total_len;
 216         call->key               = key_get(cp->key);
 217         call->local             = rxrpc_get_local(cp->local, rxrpc_local_get_call);
 218         call->security_level    = cp->security_level;
 219         if (p->kernel)
 220                 __set_bit(RXRPC_CALL_KERNEL, &call->flags);
 221         if (cp->upgrade)
 222                 __set_bit(RXRPC_CALL_UPGRADE, &call->flags);
 223         if (cp->exclusive)
 224                 __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
 225
 226         ret = rxrpc_init_client_call_security(call);
 227         if (ret < 0) {
 228                 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
 229                 rxrpc_put_call(call, rxrpc_call_put_discard_error);
 230                 return ERR_PTR(ret);
 231         }
 232
 233         rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
 234
 235         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
 236                          p->user_call_ID, rxrpc_call_new_client);
 237
 238         _leave(" = %p", call);
 239         return call;
 240 }
 241
 242 /*
 243  * Initiate the call ack/resend/expiry timer.
 244  */
 245 void rxrpc_start_call_timer(struct rxrpc_call *call)
 246 {
 247         unsigned long now = jiffies;
 248         unsigned long j = now + MAX_JIFFY_OFFSET;
 249
 250         call->delay_ack_at = j;
 251         call->ack_lost_at = j;
 252         call->resend_at = j;
 253         call->ping_at = j;
 254         call->keepalive_at = j;
 255         call->expect_rx_by = j;
 256         call->expect_req_by = j;
 257         call->expect_term_by = j;
 258         call->timer.expires = now;
 259 }
 260
 261 /*
 262  * Wait for a call slot to become available.
 263  */
 264 static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
 265 {
 266         struct semaphore *limiter = &rxrpc_call_limiter;
 267
 268         if (p->kernel)
 269                 limiter = &rxrpc_kernel_call_limiter;
 270         if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
 271                 down(limiter);
 272                 return limiter;
 273         }
 274         return down_interruptible(limiter) < 0 ? NULL : limiter;
 275 }
 276
 277 /*
 278  * Release a call slot.
 279  */
 280 static void rxrpc_put_call_slot(struct rxrpc_call *call)
 281 {
 282         struct semaphore *limiter = &rxrpc_call_limiter;
 283
 284         if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
 285                 limiter = &rxrpc_kernel_call_limiter;
 286         up(limiter);
 287 }
 288
 289 /*
 290  * Start the process of connecting a call.  We obtain a peer and a connection
 291  * bundle, but the actual association of a call with a connection is offloaded
 292  * to the I/O thread to simplify locking.
 293  */
 294 static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
 295 {
 296         struct rxrpc_local *local = call->local;
 297         int ret = -ENOMEM;
 298
 299         _enter("{%d,%lx},", call->debug_id, call->user_call_ID);
 300
 301         call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp);
 302         if (!call->peer)
 303                 goto error;
 304
 305         ret = rxrpc_look_up_bundle(call, gfp);
 306         if (ret < 0)
 307                 goto error;
 308
 309         trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
 310         rxrpc_get_call(call, rxrpc_call_get_io_thread);
 311         spin_lock(&local->client_call_lock);
 312         list_add_tail(&call->wait_link, &local->new_client_calls);
 313         spin_unlock(&local->client_call_lock);
 314         rxrpc_wake_up_io_thread(local);
 315         return 0;
 316
 317 error:
 318         __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
 319         return ret;
 320 }
 321
 322 /*
 323  * Set up a call for the given parameters.
 324  * - Called with the socket lock held, which it must release.
 325  * - If it returns a call, the call's lock will need releasing by the caller.
 326  */
 327 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 328                                          struct rxrpc_conn_parameters *cp,
 329                                          struct sockaddr_rxrpc *srx,
 330                                          struct rxrpc_call_params *p,
 331                                          gfp_t gfp,
 332                                          unsigned int debug_id)
 333         __releases(&rx->sk.sk_lock.slock)
 334         __acquires(&call->user_mutex)
 335 {
 336         struct rxrpc_call *call, *xcall;
 337         struct rxrpc_net *rxnet;
 338         struct semaphore *limiter;
 339         struct rb_node *parent, **pp;
 340         int ret;
 341
 342         _enter("%p,%lx", rx, p->user_call_ID);
 343
 344         limiter = rxrpc_get_call_slot(p, gfp);
 345         if (!limiter) {
 346                 release_sock(&rx->sk);
 347                 return ERR_PTR(-ERESTARTSYS);
 348         }
 349
 350         call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id);
 351         if (IS_ERR(call)) {
 352                 release_sock(&rx->sk);
 353                 up(limiter);
 354                 _leave(" = %ld", PTR_ERR(call));
 355                 return call;
 356         }
 357
 358         /* We need to protect a partially set up call against the user as we
 359          * will be acting outside the socket lock.
 360          */
 361         mutex_lock(&call->user_mutex);
 362
 363         /* Publish the call, even though it is incompletely set up as yet */
 364         write_lock(&rx->call_lock);
 365
 366         pp = &rx->calls.rb_node;
 367         parent = NULL;
 368         while (*pp) {
 369                 parent = *pp;
 370                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 371
 372                 if (p->user_call_ID < xcall->user_call_ID)
 373                         pp = &(*pp)->rb_left;
 374                 else if (p->user_call_ID > xcall->user_call_ID)
 375                         pp = &(*pp)->rb_right;
 376                 else
 377                         goto error_dup_user_ID;
 378         }
 379
 380         rcu_assign_pointer(call->socket, rx);
 381         call->user_call_ID = p->user_call_ID;
 382         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 383         rxrpc_get_call(call, rxrpc_call_get_userid);
 384         rb_link_node(&call->sock_node, parent, pp);
 385         rb_insert_color(&call->sock_node, &rx->calls);
 386         list_add(&call->sock_link, &rx->sock_calls);
 387
 388         write_unlock(&rx->call_lock);
 389
 390         rxnet = call->rxnet;
 391         spin_lock(&rxnet->call_lock);
 392         list_add_tail_rcu(&call->link, &rxnet->calls);
 393         spin_unlock(&rxnet->call_lock);
 394
 395         /* From this point on, the call is protected by its own lock. */
 396         release_sock(&rx->sk);
 397
 398         /* Set up or get a connection record and set the protocol parameters,
 399          * including channel number and call ID.
 400          */
 401         ret = rxrpc_connect_call(call, gfp);
 402         if (ret < 0)
 403                 goto error_attached_to_socket;
 404
 405         _leave(" = %p [new]", call);
 406         return call;
 407
 408         /* We unexpectedly found the user ID in the list after taking
 409          * the call_lock.  This shouldn't happen unless the user races
 410          * with itself and tries to add the same user ID twice at the
 411          * same time in different threads.
 412          */
 413 error_dup_user_ID:
 414         write_unlock(&rx->call_lock);
 415         release_sock(&rx->sk);
 416         rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
 417         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
 418                          rxrpc_call_see_userid_exists);
 419         mutex_unlock(&call->user_mutex);
 420         rxrpc_put_call(call, rxrpc_call_put_userid_exists);
 421         _leave(" = -EEXIST");
 422         return ERR_PTR(-EEXIST);
 423
 424         /* We got an error, but the call is attached to the socket and is in
 425          * need of release.  However, we might now race with recvmsg() when it
 426          * completion notifies the socket.  Return 0 from sys_sendmsg() and
 427          * leave the error to recvmsg() to deal with.
 428          */
 429 error_attached_to_socket:
 430         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
 431                          rxrpc_call_see_connect_failed);
 432         rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
 433         _leave(" = c=%08x [err]", call->debug_id);
 434         return call;
 435 }
 436
 437 /*
 438  * Set up an incoming call.  call->conn points to the connection.
 439  * This is called in BH context and isn't allowed to fail.
 440  */
 441 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 442                          struct rxrpc_call *call,
 443                          struct sk_buff *skb)
 444 {
 445         struct rxrpc_connection *conn = call->conn;
 446         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 447         u32 chan;
 448
 449         _enter(",%d", call->conn->debug_id);
 450
 451         rcu_assign_pointer(call->socket, rx);
 452         call->call_id           = sp->hdr.callNumber;
 453         call->dest_srx.srx_service = sp->hdr.serviceId;
 454         call->cid               = sp->hdr.cid;
 455         call->cong_tstamp       = skb->tstamp;
 456
 457         __set_bit(RXRPC_CALL_EXPOSED, &call->flags);
 458         rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
 459
 460         spin_lock(&conn->state_lock);
 461
 462         switch (conn->state) {
 463         case RXRPC_CONN_SERVICE_UNSECURED:
 464         case RXRPC_CONN_SERVICE_CHALLENGING:
 465                 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
 466                 break;
 467         case RXRPC_CONN_SERVICE:
 468                 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
 469                 break;
 470
 471         case RXRPC_CONN_ABORTED:
 472                 rxrpc_set_call_completion(call, conn->completion,
 473                                           conn->abort_code, conn->error);
 474                 break;
 475         default:
 476                 BUG();
 477         }
 478
 479         rxrpc_get_call(call, rxrpc_call_get_io_thread);
 480
 481         /* Set the channel for this call.  We don't get channel_lock as we're
 482          * only defending against the data_ready handler (which we're called
 483          * from) and the RESPONSE packet parser (which is only really
 484          * interested in call_counter and can cope with a disagreement with the
 485          * call pointer).
 486          */
 487         chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 488         conn->channels[chan].call_counter = call->call_id;
 489         conn->channels[chan].call_id = call->call_id;
 490         conn->channels[chan].call = call;
 491         spin_unlock(&conn->state_lock);
 492
 493         spin_lock(&conn->peer->lock);
 494         hlist_add_head(&call->error_link, &conn->peer->error_targets);
 495         spin_unlock(&conn->peer->lock);
 496
 497         rxrpc_start_call_timer(call);
 498         _leave("");
 499 }
 500
 501 /*
 502  * Note the re-emergence of a call.
 503  */
 504 void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 505 {
 506         if (call) {
 507                 int r = refcount_read(&call->ref);
 508
 509                 trace_rxrpc_call(call->debug_id, r, 0, why);
 510         }
 511 }
 512
 513 struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
 514                                       enum rxrpc_call_trace why)
 515 {
 516         int r;
 517
 518         if (!call || !__refcount_inc_not_zero(&call->ref, &r))
 519                 return NULL;
 520         trace_rxrpc_call(call->debug_id, r + 1, 0, why);
 521         return call;
 522 }
 523
 524 /*
 525  * Note the addition of a ref on a call.
 526  */
 527 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 528 {
 529         int r;
 530
 531         __refcount_inc(&call->ref, &r);
 532         trace_rxrpc_call(call->debug_id, r + 1, 0, why);
 533 }
 534
 535 /*
 536  * Clean up the Rx skb ring.
 537  */
 538 static void rxrpc_cleanup_ring(struct rxrpc_call *call)
 539 {
 540         skb_queue_purge(&call->recvmsg_queue);
 541         skb_queue_purge(&call->rx_oos_queue);
 542 }
 543
 544 /*
 545  * Detach a call from its owning socket.
 546  */
 547 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 548 {
 549         struct rxrpc_connection *conn = call->conn;
 550         bool put = false, putu = false;
 551
 552         _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
 553
 554         trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
 555                          call->flags, rxrpc_call_see_release);
 556
 557         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 558                 BUG();
 559
 560         rxrpc_put_call_slot(call);
 561
 562         /* Make sure we don't get any more notifications */
 563         spin_lock(&rx->recvmsg_lock);
 564
 565         if (!list_empty(&call->recvmsg_link)) {
 566                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 567                        call, call->events, call->flags);
 568                 list_del(&call->recvmsg_link);
 569                 put = true;
 570         }
 571
 572         /* list_empty() must return false in rxrpc_notify_socket() */
 573         call->recvmsg_link.next = NULL;
 574         call->recvmsg_link.prev = NULL;
 575
 576         spin_unlock(&rx->recvmsg_lock);
 577         if (put)
 578                 rxrpc_put_call(call, rxrpc_call_put_unnotify);
 579
 580         write_lock(&rx->call_lock);
 581
 582         if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 583                 rb_erase(&call->sock_node, &rx->calls);
 584                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 585                 putu = true;
 586         }
 587
 588         list_del(&call->sock_link);
 589         write_unlock(&rx->call_lock);
 590
 591         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 592
 593         if (putu)
 594                 rxrpc_put_call(call, rxrpc_call_put_userid);
 595
 596         _leave("");
 597 }
 598
 599 /*
 600  * release all the calls associated with a socket
 601  */
 602 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 603 {
 604         struct rxrpc_call *call;
 605
 606         _enter("%p", rx);
 607
 608         while (!list_empty(&rx->to_be_accepted)) {
 609                 call = list_entry(rx->to_be_accepted.next,
 610                                   struct rxrpc_call, accept_link);
 611                 list_del(&call->accept_link);
 612                 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
 613                                     rxrpc_abort_call_sock_release_tba);
 614                 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
 615         }
 616
 617         while (!list_empty(&rx->sock_calls)) {
 618                 call = list_entry(rx->sock_calls.next,
 619                                   struct rxrpc_call, sock_link);
 620                 rxrpc_get_call(call, rxrpc_call_get_release_sock);
 621                 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
 622                                     rxrpc_abort_call_sock_release);
 623                 rxrpc_release_call(rx, call);
 624                 rxrpc_put_call(call, rxrpc_call_put_release_sock);
 625         }
 626
 627         _leave("");
 628 }
 629
 630 /*
 631  * release a call
 632  */
 633 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 634 {
 635         struct rxrpc_net *rxnet = call->rxnet;
 636         unsigned int debug_id = call->debug_id;
 637         bool dead;
 638         int r;
 639
 640         ASSERT(call != NULL);
 641
 642         dead = __refcount_dec_and_test(&call->ref, &r);
 643         trace_rxrpc_call(debug_id, r - 1, 0, why);
 644         if (dead) {
 645                 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 646
 647                 if (!list_empty(&call->link)) {
 648                         spin_lock(&rxnet->call_lock);
 649                         list_del_init(&call->link);
 650                         spin_unlock(&rxnet->call_lock);
 651                 }
 652
 653                 rxrpc_cleanup_call(call);
 654         }
 655 }
 656
 657 /*
 658  * Free up the call under RCU.
 659  */
 660 static void rxrpc_rcu_free_call(struct rcu_head *rcu)
 661 {
 662         struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
 663         struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
 664
 665         kmem_cache_free(rxrpc_call_jar, call);
 666         if (atomic_dec_and_test(&rxnet->nr_calls))
 667                 wake_up_var(&rxnet->nr_calls);
 668 }
 669
 670 /*
 671  * Final call destruction - but must be done in process context.
 672  */
 673 static void rxrpc_destroy_call(struct work_struct *work)
 674 {
 675         struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
 676         struct rxrpc_txbuf *txb;
 677
 678         del_timer_sync(&call->timer);
 679
 680         rxrpc_cleanup_ring(call);
 681         while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
 682                                                struct rxrpc_txbuf, call_link))) {
 683                 list_del(&txb->call_link);
 684                 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
 685         }
 686         while ((txb = list_first_entry_or_null(&call->tx_buffer,
 687                                                struct rxrpc_txbuf, call_link))) {
 688                 list_del(&txb->call_link);
 689                 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
 690         }
 691
 692         rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
 693         rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
 694         rxrpc_deactivate_bundle(call->bundle);
 695         rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
 696         rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
 697         rxrpc_put_local(call->local, rxrpc_local_put_call);
 698         call_rcu(&call->rcu, rxrpc_rcu_free_call);
 699 }
 700
 701 /*
 702  * clean up a call
 703  */
 704 void rxrpc_cleanup_call(struct rxrpc_call *call)
 705 {
 706         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 707
 708         ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 709         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 710
 711         del_timer(&call->timer);
 712
 713         if (rcu_read_lock_held())
 714                 /* Can't use the rxrpc workqueue as we need to cancel/flush
 715                  * something that may be running/waiting there.
 716                  */
 717                 schedule_work(&call->destroyer);
 718         else
 719                 rxrpc_destroy_call(&call->destroyer);
 720 }
 721
 722 /*
 723  * Make sure that all calls are gone from a network namespace.  To reach this
 724  * point, any open UDP sockets in that namespace must have been closed, so any
 725  * outstanding calls cannot be doing I/O.
 726  */
 727 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 728 {
 729         struct rxrpc_call *call;
 730
 731         _enter("");
 732
 733         if (!list_empty(&rxnet->calls)) {
 734                 spin_lock(&rxnet->call_lock);
 735
 736                 while (!list_empty(&rxnet->calls)) {
 737                         call = list_entry(rxnet->calls.next,
 738                                           struct rxrpc_call, link);
 739                         _debug("Zapping call %p", call);
 740
 741                         rxrpc_see_call(call, rxrpc_call_see_zap);
 742                         list_del_init(&call->link);
 743
 744                         pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 745                                call, refcount_read(&call->ref),
 746                                rxrpc_call_states[__rxrpc_call_state(call)],
 747                                call->flags, call->events);
 748
 749                         spin_unlock(&rxnet->call_lock);
 750                         cond_resched();
 751                         spin_lock(&rxnet->call_lock);
 752                 }
 753
 754                 spin_unlock(&rxnet->call_lock);
 755         }
 756
 757         atomic_dec(&rxnet->nr_calls);
 758         wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 759 }