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/hashtable.h>
  18 #include <linux/spinlock_types.h>
  19 #include <net/sock.h>
  20 #include <net/af_rxrpc.h>
  21 #include "ar-internal.h"
  22
  23 /*
  24  * Maximum lifetime of a call (in jiffies).
  25  */
  26 unsigned int rxrpc_max_call_lifetime = 60 * HZ;
  27
  28 /*
  29  * Time till dead call expires after last use (in jiffies).
  30  */
  31 unsigned int rxrpc_dead_call_expiry = 2 * HZ;
  32
  33 const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
  34         [RXRPC_CALL_CLIENT_SEND_REQUEST]        = "ClSndReq",
  35         [RXRPC_CALL_CLIENT_AWAIT_REPLY]         = "ClAwtRpl",
  36         [RXRPC_CALL_CLIENT_RECV_REPLY]          = "ClRcvRpl",
  37         [RXRPC_CALL_CLIENT_FINAL_ACK]           = "ClFnlACK",
  38         [RXRPC_CALL_SERVER_SECURING]            = "SvSecure",
  39         [RXRPC_CALL_SERVER_ACCEPTING]           = "SvAccept",
  40         [RXRPC_CALL_SERVER_RECV_REQUEST]        = "SvRcvReq",
  41         [RXRPC_CALL_SERVER_ACK_REQUEST]         = "SvAckReq",
  42         [RXRPC_CALL_SERVER_SEND_REPLY]          = "SvSndRpl",
  43         [RXRPC_CALL_SERVER_AWAIT_ACK]           = "SvAwtACK",
  44         [RXRPC_CALL_COMPLETE]                   = "Complete",
  45         [RXRPC_CALL_SERVER_BUSY]                = "SvBusy  ",
  46         [RXRPC_CALL_REMOTELY_ABORTED]           = "RmtAbort",
  47         [RXRPC_CALL_LOCALLY_ABORTED]            = "LocAbort",
  48         [RXRPC_CALL_NETWORK_ERROR]              = "NetError",
  49         [RXRPC_CALL_DEAD]                       = "Dead    ",
  50 };
  51
  52 struct kmem_cache *rxrpc_call_jar;
  53 LIST_HEAD(rxrpc_calls);
  54 DEFINE_RWLOCK(rxrpc_call_lock);
  55
  56 static void rxrpc_destroy_call(struct work_struct *work);
  57 static void rxrpc_call_life_expired(unsigned long _call);
  58 static void rxrpc_dead_call_expired(unsigned long _call);
  59 static void rxrpc_ack_time_expired(unsigned long _call);
  60 static void rxrpc_resend_time_expired(unsigned long _call);
  61
  62 static DEFINE_SPINLOCK(rxrpc_call_hash_lock);
  63 static DEFINE_HASHTABLE(rxrpc_call_hash, 10);
  64
  65 /*
  66  * Hash function for rxrpc_call_hash
  67  */
  68 static unsigned long rxrpc_call_hashfunc(
  69         u8              in_clientflag,
  70         u32             cid,
  71         u32             call_id,
  72         u32             epoch,
  73         u16             service_id,
  74         sa_family_t     proto,
  75         void            *localptr,
  76         unsigned int    addr_size,
  77         const u8        *peer_addr)
  78 {
  79         const u16 *p;
  80         unsigned int i;
  81         unsigned long key;
  82
  83         _enter("");
  84
  85         key = (unsigned long)localptr;
  86         /* We just want to add up the __be32 values, so forcing the
  87          * cast should be okay.
  88          */
  89         key += epoch;
  90         key += service_id;
  91         key += call_id;
  92         key += (cid & RXRPC_CIDMASK) >> RXRPC_CIDSHIFT;
  93         key += cid & RXRPC_CHANNELMASK;
  94         key += in_clientflag;
  95         key += proto;
  96         /* Step through the peer address in 16-bit portions for speed */
  97         for (i = 0, p = (const u16 *)peer_addr; i < addr_size >> 1; i++, p++)
  98                 key += *p;
  99         _leave(" key = 0x%lx", key);
 100         return key;
 101 }
 102
 103 /*
 104  * Add a call to the hashtable
 105  */
 106 static void rxrpc_call_hash_add(struct rxrpc_call *call)
 107 {
 108         unsigned long key;
 109         unsigned int addr_size = 0;
 110
 111         _enter("");
 112         switch (call->proto) {
 113         case AF_INET:
 114                 addr_size = sizeof(call->peer_ip.ipv4_addr);
 115                 break;
 116         case AF_INET6:
 117                 addr_size = sizeof(call->peer_ip.ipv6_addr);
 118                 break;
 119         default:
 120                 break;
 121         }
 122         key = rxrpc_call_hashfunc(call->in_clientflag, call->cid,
 123                                   call->call_id, call->epoch,
 124                                   call->service_id, call->proto,
 125                                   call->conn->trans->local, addr_size,
 126                                   call->peer_ip.ipv6_addr);
 127         /* Store the full key in the call */
 128         call->hash_key = key;
 129         spin_lock(&rxrpc_call_hash_lock);
 130         hash_add_rcu(rxrpc_call_hash, &call->hash_node, key);
 131         spin_unlock(&rxrpc_call_hash_lock);
 132         _leave("");
 133 }
 134
 135 /*
 136  * Remove a call from the hashtable
 137  */
 138 static void rxrpc_call_hash_del(struct rxrpc_call *call)
 139 {
 140         _enter("");
 141         spin_lock(&rxrpc_call_hash_lock);
 142         hash_del_rcu(&call->hash_node);
 143         spin_unlock(&rxrpc_call_hash_lock);
 144         _leave("");
 145 }
 146
 147 /*
 148  * Find a call in the hashtable and return it, or NULL if it
 149  * isn't there.
 150  */
 151 struct rxrpc_call *rxrpc_find_call_hash(
 152         struct rxrpc_host_header *hdr,
 153         void            *localptr,
 154         sa_family_t     proto,
 155         const void      *peer_addr)
 156 {
 157         unsigned long key;
 158         unsigned int addr_size = 0;
 159         struct rxrpc_call *call = NULL;
 160         struct rxrpc_call *ret = NULL;
 161         u8 in_clientflag = hdr->flags & RXRPC_CLIENT_INITIATED;
 162
 163         _enter("");
 164         switch (proto) {
 165         case AF_INET:
 166                 addr_size = sizeof(call->peer_ip.ipv4_addr);
 167                 break;
 168         case AF_INET6:
 169                 addr_size = sizeof(call->peer_ip.ipv6_addr);
 170                 break;
 171         default:
 172                 break;
 173         }
 174
 175         key = rxrpc_call_hashfunc(in_clientflag, hdr->cid, hdr->callNumber,
 176                                   hdr->epoch, hdr->serviceId,
 177                                   proto, localptr, addr_size,
 178                                   peer_addr);
 179         hash_for_each_possible_rcu(rxrpc_call_hash, call, hash_node, key) {
 180                 if (call->hash_key == key &&
 181                     call->call_id == hdr->callNumber &&
 182                     call->cid == hdr->cid &&
 183                     call->in_clientflag == in_clientflag &&
 184                     call->service_id == hdr->serviceId &&
 185                     call->proto == proto &&
 186                     call->local == localptr &&
 187                     memcmp(call->peer_ip.ipv6_addr, peer_addr,
 188                            addr_size) == 0 &&
 189                     call->epoch == hdr->epoch) {
 190                         ret = call;
 191                         break;
 192                 }
 193         }
 194         _leave(" = %p", ret);
 195         return ret;
 196 }
 197
 198 /*
 199  * find an extant server call
 200  * - called in process context with IRQs enabled
 201  */
 202 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
 203                                               unsigned long user_call_ID)
 204 {
 205         struct rxrpc_call *call;
 206         struct rb_node *p;
 207
 208         _enter("%p,%lx", rx, user_call_ID);
 209
 210         read_lock(&rx->call_lock);
 211
 212         p = rx->calls.rb_node;
 213         while (p) {
 214                 call = rb_entry(p, struct rxrpc_call, sock_node);
 215
 216                 if (user_call_ID < call->user_call_ID)
 217                         p = p->rb_left;
 218                 else if (user_call_ID > call->user_call_ID)
 219                         p = p->rb_right;
 220                 else
 221                         goto found_extant_call;
 222         }
 223
 224         read_unlock(&rx->call_lock);
 225         _leave(" = NULL");
 226         return NULL;
 227
 228 found_extant_call:
 229         rxrpc_get_call(call);
 230         read_unlock(&rx->call_lock);
 231         _leave(" = %p [%d]", call, atomic_read(&call->usage));
 232         return call;
 233 }
 234
 235 /*
 236  * allocate a new call
 237  */
 238 static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
 239 {
 240         struct rxrpc_call *call;
 241
 242         call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
 243         if (!call)
 244                 return NULL;
 245
 246         call->acks_winsz = 16;
 247         call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
 248                                     gfp);
 249         if (!call->acks_window) {
 250                 kmem_cache_free(rxrpc_call_jar, call);
 251                 return NULL;
 252         }
 253
 254         setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
 255                     (unsigned long) call);
 256         setup_timer(&call->deadspan, &rxrpc_dead_call_expired,
 257                     (unsigned long) call);
 258         setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
 259                     (unsigned long) call);
 260         setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
 261                     (unsigned long) call);
 262         INIT_WORK(&call->destroyer, &rxrpc_destroy_call);
 263         INIT_WORK(&call->processor, &rxrpc_process_call);
 264         INIT_LIST_HEAD(&call->accept_link);
 265         skb_queue_head_init(&call->rx_queue);
 266         skb_queue_head_init(&call->rx_oos_queue);
 267         init_waitqueue_head(&call->tx_waitq);
 268         spin_lock_init(&call->lock);
 269         rwlock_init(&call->state_lock);
 270         atomic_set(&call->usage, 1);
 271         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 272         call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
 273
 274         memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 275
 276         call->rx_data_expect = 1;
 277         call->rx_data_eaten = 0;
 278         call->rx_first_oos = 0;
 279         call->ackr_win_top = call->rx_data_eaten + 1 + rxrpc_rx_window_size;
 280         call->creation_jif = jiffies;
 281         return call;
 282 }
 283
 284 /*
 285  * allocate a new client call and attempt to get a connection slot for it
 286  */
 287 static struct rxrpc_call *rxrpc_alloc_client_call(
 288         struct rxrpc_sock *rx,
 289         struct rxrpc_transport *trans,
 290         struct rxrpc_conn_bundle *bundle,
 291         gfp_t gfp)
 292 {
 293         struct rxrpc_call *call;
 294         int ret;
 295
 296         _enter("");
 297
 298         ASSERT(rx != NULL);
 299         ASSERT(trans != NULL);
 300         ASSERT(bundle != NULL);
 301
 302         call = rxrpc_alloc_call(gfp);
 303         if (!call)
 304                 return ERR_PTR(-ENOMEM);
 305
 306         sock_hold(&rx->sk);
 307         call->socket = rx;
 308         call->rx_data_post = 1;
 309
 310         ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
 311         if (ret < 0) {
 312                 kmem_cache_free(rxrpc_call_jar, call);
 313                 return ERR_PTR(ret);
 314         }
 315
 316         /* Record copies of information for hashtable lookup */
 317         call->proto = rx->proto;
 318         call->local = trans->local;
 319         switch (call->proto) {
 320         case AF_INET:
 321                 call->peer_ip.ipv4_addr =
 322                         trans->peer->srx.transport.sin.sin_addr.s_addr;
 323                 break;
 324         case AF_INET6:
 325                 memcpy(call->peer_ip.ipv6_addr,
 326                        trans->peer->srx.transport.sin6.sin6_addr.in6_u.u6_addr8,
 327                        sizeof(call->peer_ip.ipv6_addr));
 328                 break;
 329         }
 330         call->epoch = call->conn->epoch;
 331         call->service_id = call->conn->service_id;
 332         call->in_clientflag = call->conn->in_clientflag;
 333         /* Add the new call to the hashtable */
 334         rxrpc_call_hash_add(call);
 335
 336         spin_lock(&call->conn->trans->peer->lock);
 337         hlist_add_head(&call->error_link, &call->conn->trans->peer->error_targets);
 338         spin_unlock(&call->conn->trans->peer->lock);
 339
 340         call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 341         add_timer(&call->lifetimer);
 342
 343         _leave(" = %p", call);
 344         return call;
 345 }
 346
 347 /*
 348  * set up a call for the given data
 349  * - called in process context with IRQs enabled
 350  */
 351 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 352                                          struct rxrpc_transport *trans,
 353                                          struct rxrpc_conn_bundle *bundle,
 354                                          unsigned long user_call_ID,
 355                                          gfp_t gfp)
 356 {
 357         struct rxrpc_call *call, *xcall;
 358         struct rb_node *parent, **pp;
 359
 360         _enter("%p,%d,%d,%lx",
 361                rx, trans->debug_id, bundle ? bundle->debug_id : -1,
 362                user_call_ID);
 363
 364         call = rxrpc_alloc_client_call(rx, trans, bundle, gfp);
 365         if (IS_ERR(call)) {
 366                 _leave(" = %ld", PTR_ERR(call));
 367                 return call;
 368         }
 369
 370         call->user_call_ID = user_call_ID;
 371         __set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 372
 373         write_lock(&rx->call_lock);
 374
 375         pp = &rx->calls.rb_node;
 376         parent = NULL;
 377         while (*pp) {
 378                 parent = *pp;
 379                 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
 380
 381                 if (user_call_ID < xcall->user_call_ID)
 382                         pp = &(*pp)->rb_left;
 383                 else if (user_call_ID > xcall->user_call_ID)
 384                         pp = &(*pp)->rb_right;
 385                 else
 386                         goto found_user_ID_now_present;
 387         }
 388
 389         rxrpc_get_call(call);
 390
 391         rb_link_node(&call->sock_node, parent, pp);
 392         rb_insert_color(&call->sock_node, &rx->calls);
 393         write_unlock(&rx->call_lock);
 394
 395         write_lock_bh(&rxrpc_call_lock);
 396         list_add_tail(&call->link, &rxrpc_calls);
 397         write_unlock_bh(&rxrpc_call_lock);
 398
 399         _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
 400
 401         _leave(" = %p [new]", call);
 402         return call;
 403
 404         /* We unexpectedly found the user ID in the list after taking
 405          * the call_lock.  This shouldn't happen unless the user races
 406          * with itself and tries to add the same user ID twice at the
 407          * same time in different threads.
 408          */
 409 found_user_ID_now_present:
 410         write_unlock(&rx->call_lock);
 411         rxrpc_put_call(call);
 412         _leave(" = -EEXIST [%p]", call);
 413         return ERR_PTR(-EEXIST);
 414 }
 415
 416 /*
 417  * set up an incoming call
 418  * - called in process context with IRQs enabled
 419  */
 420 struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
 421                                        struct rxrpc_connection *conn,
 422                                        struct rxrpc_host_header *hdr)
 423 {
 424         struct rxrpc_call *call, *candidate;
 425         struct rb_node **p, *parent;
 426         u32 call_id;
 427
 428         _enter(",%d", conn->debug_id);
 429
 430         ASSERT(rx != NULL);
 431
 432         candidate = rxrpc_alloc_call(GFP_NOIO);
 433         if (!candidate)
 434                 return ERR_PTR(-EBUSY);
 435
 436         candidate->socket = rx;
 437         candidate->conn = conn;
 438         candidate->cid = hdr->cid;
 439         candidate->call_id = hdr->callNumber;
 440         candidate->channel = hdr->cid & RXRPC_CHANNELMASK;
 441         candidate->rx_data_post = 0;
 442         candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
 443         if (conn->security_ix > 0)
 444                 candidate->state = RXRPC_CALL_SERVER_SECURING;
 445
 446         write_lock_bh(&conn->lock);
 447
 448         /* set the channel for this call */
 449         call = conn->channels[candidate->channel];
 450         _debug("channel[%u] is %p", candidate->channel, call);
 451         if (call && call->call_id == hdr->callNumber) {
 452                 /* already set; must've been a duplicate packet */
 453                 _debug("extant call [%d]", call->state);
 454                 ASSERTCMP(call->conn, ==, conn);
 455
 456                 read_lock(&call->state_lock);
 457                 switch (call->state) {
 458                 case RXRPC_CALL_LOCALLY_ABORTED:
 459                         if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events))
 460                                 rxrpc_queue_call(call);
 461                 case RXRPC_CALL_REMOTELY_ABORTED:
 462                         read_unlock(&call->state_lock);
 463                         goto aborted_call;
 464                 default:
 465                         rxrpc_get_call(call);
 466                         read_unlock(&call->state_lock);
 467                         goto extant_call;
 468                 }
 469         }
 470
 471         if (call) {
 472                 /* it seems the channel is still in use from the previous call
 473                  * - ditch the old binding if its call is now complete */
 474                 _debug("CALL: %u { %s }",
 475                        call->debug_id, rxrpc_call_states[call->state]);
 476
 477                 if (call->state >= RXRPC_CALL_COMPLETE) {
 478                         conn->channels[call->channel] = NULL;
 479                 } else {
 480                         write_unlock_bh(&conn->lock);
 481                         kmem_cache_free(rxrpc_call_jar, candidate);
 482                         _leave(" = -EBUSY");
 483                         return ERR_PTR(-EBUSY);
 484                 }
 485         }
 486
 487         /* check the call number isn't duplicate */
 488         _debug("check dup");
 489         call_id = hdr->callNumber;
 490         p = &conn->calls.rb_node;
 491         parent = NULL;
 492         while (*p) {
 493                 parent = *p;
 494                 call = rb_entry(parent, struct rxrpc_call, conn_node);
 495
 496                 /* The tree is sorted in order of the __be32 value without
 497                  * turning it into host order.
 498                  */
 499                 if (call_id < call->call_id)
 500                         p = &(*p)->rb_left;
 501                 else if (call_id > call->call_id)
 502                         p = &(*p)->rb_right;
 503                 else
 504                         goto old_call;
 505         }
 506
 507         /* make the call available */
 508         _debug("new call");
 509         call = candidate;
 510         candidate = NULL;
 511         rb_link_node(&call->conn_node, parent, p);
 512         rb_insert_color(&call->conn_node, &conn->calls);
 513         conn->channels[call->channel] = call;
 514         sock_hold(&rx->sk);
 515         atomic_inc(&conn->usage);
 516         write_unlock_bh(&conn->lock);
 517
 518         spin_lock(&conn->trans->peer->lock);
 519         hlist_add_head(&call->error_link, &conn->trans->peer->error_targets);
 520         spin_unlock(&conn->trans->peer->lock);
 521
 522         write_lock_bh(&rxrpc_call_lock);
 523         list_add_tail(&call->link, &rxrpc_calls);
 524         write_unlock_bh(&rxrpc_call_lock);
 525
 526         /* Record copies of information for hashtable lookup */
 527         call->proto = rx->proto;
 528         call->local = conn->trans->local;
 529         switch (call->proto) {
 530         case AF_INET:
 531                 call->peer_ip.ipv4_addr =
 532                         conn->trans->peer->srx.transport.sin.sin_addr.s_addr;
 533                 break;
 534         case AF_INET6:
 535                 memcpy(call->peer_ip.ipv6_addr,
 536                        conn->trans->peer->srx.transport.sin6.sin6_addr.in6_u.u6_addr8,
 537                        sizeof(call->peer_ip.ipv6_addr));
 538                 break;
 539         default:
 540                 break;
 541         }
 542         call->epoch = conn->epoch;
 543         call->service_id = conn->service_id;
 544         call->in_clientflag = conn->in_clientflag;
 545         /* Add the new call to the hashtable */
 546         rxrpc_call_hash_add(call);
 547
 548         _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 549
 550         call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 551         add_timer(&call->lifetimer);
 552         _leave(" = %p {%d} [new]", call, call->debug_id);
 553         return call;
 554
 555 extant_call:
 556         write_unlock_bh(&conn->lock);
 557         kmem_cache_free(rxrpc_call_jar, candidate);
 558         _leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
 559         return call;
 560
 561 aborted_call:
 562         write_unlock_bh(&conn->lock);
 563         kmem_cache_free(rxrpc_call_jar, candidate);
 564         _leave(" = -ECONNABORTED");
 565         return ERR_PTR(-ECONNABORTED);
 566
 567 old_call:
 568         write_unlock_bh(&conn->lock);
 569         kmem_cache_free(rxrpc_call_jar, candidate);
 570         _leave(" = -ECONNRESET [old]");
 571         return ERR_PTR(-ECONNRESET);
 572 }
 573
 574 /*
 575  * detach a call from a socket and set up for release
 576  */
 577 void rxrpc_release_call(struct rxrpc_call *call)
 578 {
 579         struct rxrpc_connection *conn = call->conn;
 580         struct rxrpc_sock *rx = call->socket;
 581
 582         _enter("{%d,%d,%d,%d}",
 583                call->debug_id, atomic_read(&call->usage),
 584                atomic_read(&call->ackr_not_idle),
 585                call->rx_first_oos);
 586
 587         spin_lock_bh(&call->lock);
 588         if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 589                 BUG();
 590         spin_unlock_bh(&call->lock);
 591
 592         /* dissociate from the socket
 593          * - the socket's ref on the call is passed to the death timer
 594          */
 595         _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 596
 597         write_lock_bh(&rx->call_lock);
 598         if (!list_empty(&call->accept_link)) {
 599                 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
 600                        call, call->events, call->flags);
 601                 ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
 602                 list_del_init(&call->accept_link);
 603                 sk_acceptq_removed(&rx->sk);
 604         } else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 605                 rb_erase(&call->sock_node, &rx->calls);
 606                 memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
 607                 clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
 608         }
 609         write_unlock_bh(&rx->call_lock);
 610
 611         /* free up the channel for reuse */
 612         spin_lock(&conn->trans->client_lock);
 613         write_lock_bh(&conn->lock);
 614         write_lock(&call->state_lock);
 615
 616         if (conn->channels[call->channel] == call)
 617                 conn->channels[call->channel] = NULL;
 618
 619         if (conn->out_clientflag && conn->bundle) {
 620                 conn->avail_calls++;
 621                 switch (conn->avail_calls) {
 622                 case 1:
 623                         list_move_tail(&conn->bundle_link,
 624                                        &conn->bundle->avail_conns);
 625                 case 2 ... RXRPC_MAXCALLS - 1:
 626                         ASSERT(conn->channels[0] == NULL ||
 627                                conn->channels[1] == NULL ||
 628                                conn->channels[2] == NULL ||
 629                                conn->channels[3] == NULL);
 630                         break;
 631                 case RXRPC_MAXCALLS:
 632                         list_move_tail(&conn->bundle_link,
 633                                        &conn->bundle->unused_conns);
 634                         ASSERT(conn->channels[0] == NULL &&
 635                                conn->channels[1] == NULL &&
 636                                conn->channels[2] == NULL &&
 637                                conn->channels[3] == NULL);
 638                         break;
 639                 default:
 640                         pr_err("conn->avail_calls=%d\n", conn->avail_calls);
 641                         BUG();
 642                 }
 643         }
 644
 645         spin_unlock(&conn->trans->client_lock);
 646
 647         if (call->state < RXRPC_CALL_COMPLETE &&
 648             call->state != RXRPC_CALL_CLIENT_FINAL_ACK) {
 649                 _debug("+++ ABORTING STATE %d +++\n", call->state);
 650                 call->state = RXRPC_CALL_LOCALLY_ABORTED;
 651                 call->local_abort = RX_CALL_DEAD;
 652                 set_bit(RXRPC_CALL_EV_ABORT, &call->events);
 653                 rxrpc_queue_call(call);
 654         }
 655         write_unlock(&call->state_lock);
 656         write_unlock_bh(&conn->lock);
 657
 658         /* clean up the Rx queue */
 659         if (!skb_queue_empty(&call->rx_queue) ||
 660             !skb_queue_empty(&call->rx_oos_queue)) {
 661                 struct rxrpc_skb_priv *sp;
 662                 struct sk_buff *skb;
 663
 664                 _debug("purge Rx queues");
 665
 666                 spin_lock_bh(&call->lock);
 667                 while ((skb = skb_dequeue(&call->rx_queue)) ||
 668                        (skb = skb_dequeue(&call->rx_oos_queue))) {
 669                         sp = rxrpc_skb(skb);
 670                         if (sp->call) {
 671                                 ASSERTCMP(sp->call, ==, call);
 672                                 rxrpc_put_call(call);
 673                                 sp->call = NULL;
 674                         }
 675                         skb->destructor = NULL;
 676                         spin_unlock_bh(&call->lock);
 677
 678                         _debug("- zap %s %%%u #%u",
 679                                rxrpc_pkts[sp->hdr.type],
 680                                sp->hdr.serial, sp->hdr.seq);
 681                         rxrpc_free_skb(skb);
 682                         spin_lock_bh(&call->lock);
 683                 }
 684                 spin_unlock_bh(&call->lock);
 685
 686                 ASSERTCMP(call->state, !=, RXRPC_CALL_COMPLETE);
 687         }
 688
 689         del_timer_sync(&call->resend_timer);
 690         del_timer_sync(&call->ack_timer);
 691         del_timer_sync(&call->lifetimer);
 692         call->deadspan.expires = jiffies + rxrpc_dead_call_expiry;
 693         add_timer(&call->deadspan);
 694
 695         _leave("");
 696 }
 697
 698 /*
 699  * handle a dead call being ready for reaping
 700  */
 701 static void rxrpc_dead_call_expired(unsigned long _call)
 702 {
 703         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 704
 705         _enter("{%d}", call->debug_id);
 706
 707         write_lock_bh(&call->state_lock);
 708         call->state = RXRPC_CALL_DEAD;
 709         write_unlock_bh(&call->state_lock);
 710         rxrpc_put_call(call);
 711 }
 712
 713 /*
 714  * mark a call as to be released, aborting it if it's still in progress
 715  * - called with softirqs disabled
 716  */
 717 static void rxrpc_mark_call_released(struct rxrpc_call *call)
 718 {
 719         bool sched;
 720
 721         write_lock(&call->state_lock);
 722         if (call->state < RXRPC_CALL_DEAD) {
 723                 sched = false;
 724                 if (call->state < RXRPC_CALL_COMPLETE) {
 725                         _debug("abort call %p", call);
 726                         call->state = RXRPC_CALL_LOCALLY_ABORTED;
 727                         call->local_abort = RX_CALL_DEAD;
 728                         if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events))
 729                                 sched = true;
 730                 }
 731                 if (!test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
 732                         sched = true;
 733                 if (sched)
 734                         rxrpc_queue_call(call);
 735         }
 736         write_unlock(&call->state_lock);
 737 }
 738
 739 /*
 740  * release all the calls associated with a socket
 741  */
 742 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 743 {
 744         struct rxrpc_call *call;
 745         struct rb_node *p;
 746
 747         _enter("%p", rx);
 748
 749         read_lock_bh(&rx->call_lock);
 750
 751         /* mark all the calls as no longer wanting incoming packets */
 752         for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
 753                 call = rb_entry(p, struct rxrpc_call, sock_node);
 754                 rxrpc_mark_call_released(call);
 755         }
 756
 757         /* kill the not-yet-accepted incoming calls */
 758         list_for_each_entry(call, &rx->secureq, accept_link) {
 759                 rxrpc_mark_call_released(call);
 760         }
 761
 762         list_for_each_entry(call, &rx->acceptq, accept_link) {
 763                 rxrpc_mark_call_released(call);
 764         }
 765
 766         read_unlock_bh(&rx->call_lock);
 767         _leave("");
 768 }
 769
 770 /*
 771  * release a call
 772  */
 773 void __rxrpc_put_call(struct rxrpc_call *call)
 774 {
 775         ASSERT(call != NULL);
 776
 777         _enter("%p{u=%d}", call, atomic_read(&call->usage));
 778
 779         ASSERTCMP(atomic_read(&call->usage), >, 0);
 780
 781         if (atomic_dec_and_test(&call->usage)) {
 782                 _debug("call %d dead", call->debug_id);
 783                 ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
 784                 rxrpc_queue_work(&call->destroyer);
 785         }
 786         _leave("");
 787 }
 788
 789 /*
 790  * clean up a call
 791  */
 792 static void rxrpc_cleanup_call(struct rxrpc_call *call)
 793 {
 794         _net("DESTROY CALL %d", call->debug_id);
 795
 796         ASSERT(call->socket);
 797
 798         memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 799
 800         del_timer_sync(&call->lifetimer);
 801         del_timer_sync(&call->deadspan);
 802         del_timer_sync(&call->ack_timer);
 803         del_timer_sync(&call->resend_timer);
 804
 805         ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
 806         ASSERTCMP(call->events, ==, 0);
 807         if (work_pending(&call->processor)) {
 808                 _debug("defer destroy");
 809                 rxrpc_queue_work(&call->destroyer);
 810                 return;
 811         }
 812
 813         if (call->conn) {
 814                 spin_lock(&call->conn->trans->peer->lock);
 815                 hlist_del_init(&call->error_link);
 816                 spin_unlock(&call->conn->trans->peer->lock);
 817
 818                 write_lock_bh(&call->conn->lock);
 819                 rb_erase(&call->conn_node, &call->conn->calls);
 820                 write_unlock_bh(&call->conn->lock);
 821                 rxrpc_put_connection(call->conn);
 822         }
 823
 824         /* Remove the call from the hash */
 825         rxrpc_call_hash_del(call);
 826
 827         if (call->acks_window) {
 828                 _debug("kill Tx window %d",
 829                        CIRC_CNT(call->acks_head, call->acks_tail,
 830                                 call->acks_winsz));
 831                 smp_mb();
 832                 while (CIRC_CNT(call->acks_head, call->acks_tail,
 833                                 call->acks_winsz) > 0) {
 834                         struct rxrpc_skb_priv *sp;
 835                         unsigned long _skb;
 836
 837                         _skb = call->acks_window[call->acks_tail] & ~1;
 838                         sp = rxrpc_skb((struct sk_buff *)_skb);
 839                         _debug("+++ clear Tx %u", sp->hdr.seq);
 840                         rxrpc_free_skb((struct sk_buff *)_skb);
 841                         call->acks_tail =
 842                                 (call->acks_tail + 1) & (call->acks_winsz - 1);
 843                 }
 844
 845                 kfree(call->acks_window);
 846         }
 847
 848         rxrpc_free_skb(call->tx_pending);
 849
 850         rxrpc_purge_queue(&call->rx_queue);
 851         ASSERT(skb_queue_empty(&call->rx_oos_queue));
 852         sock_put(&call->socket->sk);
 853         kmem_cache_free(rxrpc_call_jar, call);
 854 }
 855
 856 /*
 857  * destroy a call
 858  */
 859 static void rxrpc_destroy_call(struct work_struct *work)
 860 {
 861         struct rxrpc_call *call =
 862                 container_of(work, struct rxrpc_call, destroyer);
 863
 864         _enter("%p{%d,%d,%p}",
 865                call, atomic_read(&call->usage), call->channel, call->conn);
 866
 867         ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
 868
 869         write_lock_bh(&rxrpc_call_lock);
 870         list_del_init(&call->link);
 871         write_unlock_bh(&rxrpc_call_lock);
 872
 873         rxrpc_cleanup_call(call);
 874         _leave("");
 875 }
 876
 877 /*
 878  * preemptively destroy all the call records from a transport endpoint rather
 879  * than waiting for them to time out
 880  */
 881 void __exit rxrpc_destroy_all_calls(void)
 882 {
 883         struct rxrpc_call *call;
 884
 885         _enter("");
 886         write_lock_bh(&rxrpc_call_lock);
 887
 888         while (!list_empty(&rxrpc_calls)) {
 889                 call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
 890                 _debug("Zapping call %p", call);
 891
 892                 list_del_init(&call->link);
 893
 894                 switch (atomic_read(&call->usage)) {
 895                 case 0:
 896                         ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
 897                         break;
 898                 case 1:
 899                         if (del_timer_sync(&call->deadspan) != 0 &&
 900                             call->state != RXRPC_CALL_DEAD)
 901                                 rxrpc_dead_call_expired((unsigned long) call);
 902                         if (call->state != RXRPC_CALL_DEAD)
 903                                 break;
 904                 default:
 905                         pr_err("Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
 906                                call, atomic_read(&call->usage),
 907                                atomic_read(&call->ackr_not_idle),
 908                                rxrpc_call_states[call->state],
 909                                call->flags, call->events);
 910                         if (!skb_queue_empty(&call->rx_queue))
 911                                 pr_err("Rx queue occupied\n");
 912                         if (!skb_queue_empty(&call->rx_oos_queue))
 913                                 pr_err("OOS queue occupied\n");
 914                         break;
 915                 }
 916
 917                 write_unlock_bh(&rxrpc_call_lock);
 918                 cond_resched();
 919                 write_lock_bh(&rxrpc_call_lock);
 920         }
 921
 922         write_unlock_bh(&rxrpc_call_lock);
 923         _leave("");
 924 }
 925
 926 /*
 927  * handle call lifetime being exceeded
 928  */
 929 static void rxrpc_call_life_expired(unsigned long _call)
 930 {
 931         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 932
 933         if (call->state >= RXRPC_CALL_COMPLETE)
 934                 return;
 935
 936         _enter("{%d}", call->debug_id);
 937         read_lock_bh(&call->state_lock);
 938         if (call->state < RXRPC_CALL_COMPLETE) {
 939                 set_bit(RXRPC_CALL_EV_LIFE_TIMER, &call->events);
 940                 rxrpc_queue_call(call);
 941         }
 942         read_unlock_bh(&call->state_lock);
 943 }
 944
 945 /*
 946  * handle resend timer expiry
 947  * - may not take call->state_lock as this can deadlock against del_timer_sync()
 948  */
 949 static void rxrpc_resend_time_expired(unsigned long _call)
 950 {
 951         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 952
 953         _enter("{%d}", call->debug_id);
 954
 955         if (call->state >= RXRPC_CALL_COMPLETE)
 956                 return;
 957
 958         clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
 959         if (!test_and_set_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events))
 960                 rxrpc_queue_call(call);
 961 }
 962
 963 /*
 964  * handle ACK timer expiry
 965  */
 966 static void rxrpc_ack_time_expired(unsigned long _call)
 967 {
 968         struct rxrpc_call *call = (struct rxrpc_call *) _call;
 969
 970         _enter("{%d}", call->debug_id);
 971
 972         if (call->state >= RXRPC_CALL_COMPLETE)
 973                 return;
 974
 975         read_lock_bh(&call->state_lock);
 976         if (call->state < RXRPC_CALL_COMPLETE &&
 977             !test_and_set_bit(RXRPC_CALL_EV_ACK, &call->events))
 978                 rxrpc_queue_call(call);
 979         read_unlock_bh(&call->state_lock);
 980 }