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 DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000); 44 static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000); 45 46 void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what) 47 { 48 struct rxrpc_local *local = call->local; 49 bool busy; 50 51 if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) { 52 spin_lock_bh(&local->lock); 53 busy = !list_empty(&call->attend_link); 54 trace_rxrpc_poke_call(call, busy, what); 55 if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke)) 56 busy = true; 57 if (!busy) { 58 list_add_tail(&call->attend_link, &local->call_attend_q); 59 } 60 spin_unlock_bh(&local->lock); 61 if (!busy) 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 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 = cp->peer->srx; 214 call->dest_srx.srx_service = cp->service_id; 215 call->interruptibility = p->interruptibility; 216 call->tx_total_len = p->tx_total_len; 217 call->key = key_get(cp->key); 218 call->peer = rxrpc_get_peer(cp->peer, rxrpc_peer_get_call); 219 call->local = rxrpc_get_local(cp->local, rxrpc_local_get_call); 220 call->security_level = cp->security_level; 221 if (p->kernel) 222 __set_bit(RXRPC_CALL_KERNEL, &call->flags); 223 if (cp->upgrade) 224 __set_bit(RXRPC_CALL_UPGRADE, &call->flags); 225 if (cp->exclusive) 226 __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags); 227 228 if (p->timeouts.normal) 229 call->next_rx_timo = min(msecs_to_jiffies(p->timeouts.normal), 1UL); 230 if (p->timeouts.idle) 231 call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL); 232 if (p->timeouts.hard) 233 call->hard_timo = p->timeouts.hard * HZ; 234 235 ret = rxrpc_init_client_call_security(call); 236 if (ret < 0) { 237 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret); 238 rxrpc_put_call(call, rxrpc_call_put_discard_error); 239 return ERR_PTR(ret); 240 } 241 242 rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN); 243 244 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 245 p->user_call_ID, rxrpc_call_new_client); 246 247 _leave(" = %p", call); 248 return call; 249 } 250 251 /* 252 * Initiate the call ack/resend/expiry timer. 253 */ 254 void rxrpc_start_call_timer(struct rxrpc_call *call) 255 { 256 unsigned long now = jiffies; 257 unsigned long j = now + MAX_JIFFY_OFFSET; 258 259 call->delay_ack_at = j; 260 call->ack_lost_at = j; 261 call->resend_at = j; 262 call->ping_at = j; 263 call->keepalive_at = j; 264 call->expect_rx_by = j; 265 call->expect_req_by = j; 266 call->expect_term_by = j + call->hard_timo; 267 call->timer.expires = now; 268 } 269 270 /* 271 * Wait for a call slot to become available. 272 */ 273 static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp) 274 { 275 struct semaphore *limiter = &rxrpc_call_limiter; 276 277 if (p->kernel) 278 limiter = &rxrpc_kernel_call_limiter; 279 if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) { 280 down(limiter); 281 return limiter; 282 } 283 return down_interruptible(limiter) < 0 ? NULL : limiter; 284 } 285 286 /* 287 * Release a call slot. 288 */ 289 static void rxrpc_put_call_slot(struct rxrpc_call *call) 290 { 291 struct semaphore *limiter = &rxrpc_call_limiter; 292 293 if (test_bit(RXRPC_CALL_KERNEL, &call->flags)) 294 limiter = &rxrpc_kernel_call_limiter; 295 up(limiter); 296 } 297 298 /* 299 * Start the process of connecting a call. We obtain a peer and a connection 300 * bundle, but the actual association of a call with a connection is offloaded 301 * to the I/O thread to simplify locking. 302 */ 303 static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp) 304 { 305 struct rxrpc_local *local = call->local; 306 int ret = -ENOMEM; 307 308 _enter("{%d,%lx},", call->debug_id, call->user_call_ID); 309 310 ret = rxrpc_look_up_bundle(call, gfp); 311 if (ret < 0) 312 goto error; 313 314 trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call); 315 rxrpc_get_call(call, rxrpc_call_get_io_thread); 316 spin_lock(&local->client_call_lock); 317 list_add_tail(&call->wait_link, &local->new_client_calls); 318 spin_unlock(&local->client_call_lock); 319 rxrpc_wake_up_io_thread(local); 320 return 0; 321 322 error: 323 __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags); 324 return ret; 325 } 326 327 /* 328 * Set up a call for the given parameters. 329 * - Called with the socket lock held, which it must release. 330 * - If it returns a call, the call's lock will need releasing by the caller. 331 */ 332 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx, 333 struct rxrpc_conn_parameters *cp, 334 struct rxrpc_call_params *p, 335 gfp_t gfp, 336 unsigned int debug_id) 337 __releases(&rx->sk.sk_lock.slock) 338 __acquires(&call->user_mutex) 339 { 340 struct rxrpc_call *call, *xcall; 341 struct rxrpc_net *rxnet; 342 struct semaphore *limiter; 343 struct rb_node *parent, **pp; 344 int ret; 345 346 _enter("%p,%lx", rx, p->user_call_ID); 347 348 if (WARN_ON_ONCE(!cp->peer)) { 349 release_sock(&rx->sk); 350 return ERR_PTR(-EIO); 351 } 352 353 limiter = rxrpc_get_call_slot(p, gfp); 354 if (!limiter) { 355 release_sock(&rx->sk); 356 return ERR_PTR(-ERESTARTSYS); 357 } 358 359 call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id); 360 if (IS_ERR(call)) { 361 release_sock(&rx->sk); 362 up(limiter); 363 _leave(" = %ld", PTR_ERR(call)); 364 return call; 365 } 366 367 /* We need to protect a partially set up call against the user as we 368 * will be acting outside the socket lock. 369 */ 370 mutex_lock(&call->user_mutex); 371 372 /* Publish the call, even though it is incompletely set up as yet */ 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 (p->user_call_ID < xcall->user_call_ID) 382 pp = &(*pp)->rb_left; 383 else if (p->user_call_ID > xcall->user_call_ID) 384 pp = &(*pp)->rb_right; 385 else 386 goto error_dup_user_ID; 387 } 388 389 rcu_assign_pointer(call->socket, rx); 390 call->user_call_ID = p->user_call_ID; 391 __set_bit(RXRPC_CALL_HAS_USERID, &call->flags); 392 rxrpc_get_call(call, rxrpc_call_get_userid); 393 rb_link_node(&call->sock_node, parent, pp); 394 rb_insert_color(&call->sock_node, &rx->calls); 395 list_add(&call->sock_link, &rx->sock_calls); 396 397 write_unlock(&rx->call_lock); 398 399 rxnet = call->rxnet; 400 spin_lock(&rxnet->call_lock); 401 list_add_tail_rcu(&call->link, &rxnet->calls); 402 spin_unlock(&rxnet->call_lock); 403 404 /* From this point on, the call is protected by its own lock. */ 405 release_sock(&rx->sk); 406 407 /* Set up or get a connection record and set the protocol parameters, 408 * including channel number and call ID. 409 */ 410 ret = rxrpc_connect_call(call, gfp); 411 if (ret < 0) 412 goto error_attached_to_socket; 413 414 _leave(" = %p [new]", call); 415 return call; 416 417 /* We unexpectedly found the user ID in the list after taking 418 * the call_lock. This shouldn't happen unless the user races 419 * with itself and tries to add the same user ID twice at the 420 * same time in different threads. 421 */ 422 error_dup_user_ID: 423 write_unlock(&rx->call_lock); 424 release_sock(&rx->sk); 425 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST); 426 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0, 427 rxrpc_call_see_userid_exists); 428 mutex_unlock(&call->user_mutex); 429 rxrpc_put_call(call, rxrpc_call_put_userid_exists); 430 _leave(" = -EEXIST"); 431 return ERR_PTR(-EEXIST); 432 433 /* We got an error, but the call is attached to the socket and is in 434 * need of release. However, we might now race with recvmsg() when it 435 * completion notifies the socket. Return 0 from sys_sendmsg() and 436 * leave the error to recvmsg() to deal with. 437 */ 438 error_attached_to_socket: 439 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret, 440 rxrpc_call_see_connect_failed); 441 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret); 442 _leave(" = c=%08x [err]", call->debug_id); 443 return call; 444 } 445 446 /* 447 * Set up an incoming call. call->conn points to the connection. 448 * This is called in BH context and isn't allowed to fail. 449 */ 450 void rxrpc_incoming_call(struct rxrpc_sock *rx, 451 struct rxrpc_call *call, 452 struct sk_buff *skb) 453 { 454 struct rxrpc_connection *conn = call->conn; 455 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 456 u32 chan; 457 458 _enter(",%d", call->conn->debug_id); 459 460 rcu_assign_pointer(call->socket, rx); 461 call->call_id = sp->hdr.callNumber; 462 call->dest_srx.srx_service = sp->hdr.serviceId; 463 call->cid = sp->hdr.cid; 464 call->cong_tstamp = skb->tstamp; 465 466 __set_bit(RXRPC_CALL_EXPOSED, &call->flags); 467 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); 468 469 spin_lock(&conn->state_lock); 470 471 switch (conn->state) { 472 case RXRPC_CONN_SERVICE_UNSECURED: 473 case RXRPC_CONN_SERVICE_CHALLENGING: 474 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); 475 break; 476 case RXRPC_CONN_SERVICE: 477 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST); 478 break; 479 480 case RXRPC_CONN_ABORTED: 481 rxrpc_set_call_completion(call, conn->completion, 482 conn->abort_code, conn->error); 483 break; 484 default: 485 BUG(); 486 } 487 488 rxrpc_get_call(call, rxrpc_call_get_io_thread); 489 490 /* Set the channel for this call. We don't get channel_lock as we're 491 * only defending against the data_ready handler (which we're called 492 * from) and the RESPONSE packet parser (which is only really 493 * interested in call_counter and can cope with a disagreement with the 494 * call pointer). 495 */ 496 chan = sp->hdr.cid & RXRPC_CHANNELMASK; 497 conn->channels[chan].call_counter = call->call_id; 498 conn->channels[chan].call_id = call->call_id; 499 conn->channels[chan].call = call; 500 spin_unlock(&conn->state_lock); 501 502 spin_lock(&conn->peer->lock); 503 hlist_add_head(&call->error_link, &conn->peer->error_targets); 504 spin_unlock(&conn->peer->lock); 505 506 rxrpc_start_call_timer(call); 507 _leave(""); 508 } 509 510 /* 511 * Note the re-emergence of a call. 512 */ 513 void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 514 { 515 if (call) { 516 int r = refcount_read(&call->ref); 517 518 trace_rxrpc_call(call->debug_id, r, 0, why); 519 } 520 } 521 522 struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call, 523 enum rxrpc_call_trace why) 524 { 525 int r; 526 527 if (!call || !__refcount_inc_not_zero(&call->ref, &r)) 528 return NULL; 529 trace_rxrpc_call(call->debug_id, r + 1, 0, why); 530 return call; 531 } 532 533 /* 534 * Note the addition of a ref on a call. 535 */ 536 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 537 { 538 int r; 539 540 __refcount_inc(&call->ref, &r); 541 trace_rxrpc_call(call->debug_id, r + 1, 0, why); 542 } 543 544 /* 545 * Clean up the Rx skb ring. 546 */ 547 static void rxrpc_cleanup_ring(struct rxrpc_call *call) 548 { 549 rxrpc_purge_queue(&call->recvmsg_queue); 550 rxrpc_purge_queue(&call->rx_oos_queue); 551 } 552 553 /* 554 * Detach a call from its owning socket. 555 */ 556 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call) 557 { 558 struct rxrpc_connection *conn = call->conn; 559 bool put = false, putu = false; 560 561 _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref)); 562 563 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 564 call->flags, rxrpc_call_see_release); 565 566 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags)) 567 BUG(); 568 569 rxrpc_put_call_slot(call); 570 571 /* Make sure we don't get any more notifications */ 572 spin_lock(&rx->recvmsg_lock); 573 574 if (!list_empty(&call->recvmsg_link)) { 575 _debug("unlinking once-pending call %p { e=%lx f=%lx }", 576 call, call->events, call->flags); 577 list_del(&call->recvmsg_link); 578 put = true; 579 } 580 581 /* list_empty() must return false in rxrpc_notify_socket() */ 582 call->recvmsg_link.next = NULL; 583 call->recvmsg_link.prev = NULL; 584 585 spin_unlock(&rx->recvmsg_lock); 586 if (put) 587 rxrpc_put_call(call, rxrpc_call_put_unnotify); 588 589 write_lock(&rx->call_lock); 590 591 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { 592 rb_erase(&call->sock_node, &rx->calls); 593 memset(&call->sock_node, 0xdd, sizeof(call->sock_node)); 594 putu = true; 595 } 596 597 list_del(&call->sock_link); 598 write_unlock(&rx->call_lock); 599 600 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn); 601 602 if (putu) 603 rxrpc_put_call(call, rxrpc_call_put_userid); 604 605 _leave(""); 606 } 607 608 /* 609 * release all the calls associated with a socket 610 */ 611 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx) 612 { 613 struct rxrpc_call *call; 614 615 _enter("%p", rx); 616 617 while (!list_empty(&rx->to_be_accepted)) { 618 call = list_entry(rx->to_be_accepted.next, 619 struct rxrpc_call, accept_link); 620 list_del(&call->accept_link); 621 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, 622 rxrpc_abort_call_sock_release_tba); 623 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba); 624 } 625 626 while (!list_empty(&rx->sock_calls)) { 627 call = list_entry(rx->sock_calls.next, 628 struct rxrpc_call, sock_link); 629 rxrpc_get_call(call, rxrpc_call_get_release_sock); 630 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, 631 rxrpc_abort_call_sock_release); 632 rxrpc_release_call(rx, call); 633 rxrpc_put_call(call, rxrpc_call_put_release_sock); 634 } 635 636 _leave(""); 637 } 638 639 /* 640 * release a call 641 */ 642 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 643 { 644 struct rxrpc_net *rxnet = call->rxnet; 645 unsigned int debug_id = call->debug_id; 646 bool dead; 647 int r; 648 649 ASSERT(call != NULL); 650 651 dead = __refcount_dec_and_test(&call->ref, &r); 652 trace_rxrpc_call(debug_id, r - 1, 0, why); 653 if (dead) { 654 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE); 655 656 if (!list_empty(&call->link)) { 657 spin_lock(&rxnet->call_lock); 658 list_del_init(&call->link); 659 spin_unlock(&rxnet->call_lock); 660 } 661 662 rxrpc_cleanup_call(call); 663 } 664 } 665 666 /* 667 * Free up the call under RCU. 668 */ 669 static void rxrpc_rcu_free_call(struct rcu_head *rcu) 670 { 671 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu); 672 struct rxrpc_net *rxnet = READ_ONCE(call->rxnet); 673 674 kmem_cache_free(rxrpc_call_jar, call); 675 if (atomic_dec_and_test(&rxnet->nr_calls)) 676 wake_up_var(&rxnet->nr_calls); 677 } 678 679 /* 680 * Final call destruction - but must be done in process context. 681 */ 682 static void rxrpc_destroy_call(struct work_struct *work) 683 { 684 struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer); 685 struct rxrpc_txbuf *txb; 686 687 del_timer_sync(&call->timer); 688 689 rxrpc_cleanup_ring(call); 690 while ((txb = list_first_entry_or_null(&call->tx_sendmsg, 691 struct rxrpc_txbuf, call_link))) { 692 list_del(&txb->call_link); 693 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned); 694 } 695 while ((txb = list_first_entry_or_null(&call->tx_buffer, 696 struct rxrpc_txbuf, call_link))) { 697 list_del(&txb->call_link); 698 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned); 699 } 700 701 rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned); 702 rxrpc_put_connection(call->conn, rxrpc_conn_put_call); 703 rxrpc_deactivate_bundle(call->bundle); 704 rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call); 705 rxrpc_put_peer(call->peer, rxrpc_peer_put_call); 706 rxrpc_put_local(call->local, rxrpc_local_put_call); 707 call_rcu(&call->rcu, rxrpc_rcu_free_call); 708 } 709 710 /* 711 * clean up a call 712 */ 713 void rxrpc_cleanup_call(struct rxrpc_call *call) 714 { 715 memset(&call->sock_node, 0xcd, sizeof(call->sock_node)); 716 717 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE); 718 ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags)); 719 720 del_timer(&call->timer); 721 722 if (rcu_read_lock_held()) 723 /* Can't use the rxrpc workqueue as we need to cancel/flush 724 * something that may be running/waiting there. 725 */ 726 schedule_work(&call->destroyer); 727 else 728 rxrpc_destroy_call(&call->destroyer); 729 } 730 731 /* 732 * Make sure that all calls are gone from a network namespace. To reach this 733 * point, any open UDP sockets in that namespace must have been closed, so any 734 * outstanding calls cannot be doing I/O. 735 */ 736 void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet) 737 { 738 struct rxrpc_call *call; 739 740 _enter(""); 741 742 if (!list_empty(&rxnet->calls)) { 743 spin_lock(&rxnet->call_lock); 744 745 while (!list_empty(&rxnet->calls)) { 746 call = list_entry(rxnet->calls.next, 747 struct rxrpc_call, link); 748 _debug("Zapping call %p", call); 749 750 rxrpc_see_call(call, rxrpc_call_see_zap); 751 list_del_init(&call->link); 752 753 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n", 754 call, refcount_read(&call->ref), 755 rxrpc_call_states[__rxrpc_call_state(call)], 756 call->flags, call->events); 757 758 spin_unlock(&rxnet->call_lock); 759 cond_resched(); 760 spin_lock(&rxnet->call_lock); 761 } 762 763 spin_unlock(&rxnet->call_lock); 764 } 765 766 atomic_dec(&rxnet->nr_calls); 767 wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls)); 768 } 769