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 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 if (p->timeouts.normal) 228 call->next_rx_timo = min(msecs_to_jiffies(p->timeouts.normal), 1UL); 229 if (p->timeouts.idle) 230 call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL); 231 if (p->timeouts.hard) 232 call->hard_timo = p->timeouts.hard * HZ; 233 234 ret = rxrpc_init_client_call_security(call); 235 if (ret < 0) { 236 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret); 237 rxrpc_put_call(call, rxrpc_call_put_discard_error); 238 return ERR_PTR(ret); 239 } 240 241 rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN); 242 243 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 244 p->user_call_ID, rxrpc_call_new_client); 245 246 _leave(" = %p", call); 247 return call; 248 } 249 250 /* 251 * Initiate the call ack/resend/expiry timer. 252 */ 253 void rxrpc_start_call_timer(struct rxrpc_call *call) 254 { 255 unsigned long now = jiffies; 256 unsigned long j = now + MAX_JIFFY_OFFSET; 257 258 call->delay_ack_at = j; 259 call->ack_lost_at = j; 260 call->resend_at = j; 261 call->ping_at = j; 262 call->keepalive_at = j; 263 call->expect_rx_by = j; 264 call->expect_req_by = j; 265 call->expect_term_by = j + call->hard_timo; 266 call->timer.expires = now; 267 } 268 269 /* 270 * Wait for a call slot to become available. 271 */ 272 static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp) 273 { 274 struct semaphore *limiter = &rxrpc_call_limiter; 275 276 if (p->kernel) 277 limiter = &rxrpc_kernel_call_limiter; 278 if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) { 279 down(limiter); 280 return limiter; 281 } 282 return down_interruptible(limiter) < 0 ? NULL : limiter; 283 } 284 285 /* 286 * Release a call slot. 287 */ 288 static void rxrpc_put_call_slot(struct rxrpc_call *call) 289 { 290 struct semaphore *limiter = &rxrpc_call_limiter; 291 292 if (test_bit(RXRPC_CALL_KERNEL, &call->flags)) 293 limiter = &rxrpc_kernel_call_limiter; 294 up(limiter); 295 } 296 297 /* 298 * Start the process of connecting a call. We obtain a peer and a connection 299 * bundle, but the actual association of a call with a connection is offloaded 300 * to the I/O thread to simplify locking. 301 */ 302 static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp) 303 { 304 struct rxrpc_local *local = call->local; 305 int ret = -ENOMEM; 306 307 _enter("{%d,%lx},", call->debug_id, call->user_call_ID); 308 309 call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp); 310 if (!call->peer) 311 goto error; 312 313 ret = rxrpc_look_up_bundle(call, gfp); 314 if (ret < 0) 315 goto error; 316 317 trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call); 318 rxrpc_get_call(call, rxrpc_call_get_io_thread); 319 spin_lock(&local->client_call_lock); 320 list_add_tail(&call->wait_link, &local->new_client_calls); 321 spin_unlock(&local->client_call_lock); 322 rxrpc_wake_up_io_thread(local); 323 return 0; 324 325 error: 326 __set_bit(RXRPC_CALL_DISCONNECTED, &call->flags); 327 return ret; 328 } 329 330 /* 331 * Set up a call for the given parameters. 332 * - Called with the socket lock held, which it must release. 333 * - If it returns a call, the call's lock will need releasing by the caller. 334 */ 335 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx, 336 struct rxrpc_conn_parameters *cp, 337 struct sockaddr_rxrpc *srx, 338 struct rxrpc_call_params *p, 339 gfp_t gfp, 340 unsigned int debug_id) 341 __releases(&rx->sk.sk_lock.slock) 342 __acquires(&call->user_mutex) 343 { 344 struct rxrpc_call *call, *xcall; 345 struct rxrpc_net *rxnet; 346 struct semaphore *limiter; 347 struct rb_node *parent, **pp; 348 int ret; 349 350 _enter("%p,%lx", rx, p->user_call_ID); 351 352 limiter = rxrpc_get_call_slot(p, gfp); 353 if (!limiter) { 354 release_sock(&rx->sk); 355 return ERR_PTR(-ERESTARTSYS); 356 } 357 358 call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id); 359 if (IS_ERR(call)) { 360 release_sock(&rx->sk); 361 up(limiter); 362 _leave(" = %ld", PTR_ERR(call)); 363 return call; 364 } 365 366 /* We need to protect a partially set up call against the user as we 367 * will be acting outside the socket lock. 368 */ 369 mutex_lock(&call->user_mutex); 370 371 /* Publish the call, even though it is incompletely set up as yet */ 372 write_lock(&rx->call_lock); 373 374 pp = &rx->calls.rb_node; 375 parent = NULL; 376 while (*pp) { 377 parent = *pp; 378 xcall = rb_entry(parent, struct rxrpc_call, sock_node); 379 380 if (p->user_call_ID < xcall->user_call_ID) 381 pp = &(*pp)->rb_left; 382 else if (p->user_call_ID > xcall->user_call_ID) 383 pp = &(*pp)->rb_right; 384 else 385 goto error_dup_user_ID; 386 } 387 388 rcu_assign_pointer(call->socket, rx); 389 call->user_call_ID = p->user_call_ID; 390 __set_bit(RXRPC_CALL_HAS_USERID, &call->flags); 391 rxrpc_get_call(call, rxrpc_call_get_userid); 392 rb_link_node(&call->sock_node, parent, pp); 393 rb_insert_color(&call->sock_node, &rx->calls); 394 list_add(&call->sock_link, &rx->sock_calls); 395 396 write_unlock(&rx->call_lock); 397 398 rxnet = call->rxnet; 399 spin_lock(&rxnet->call_lock); 400 list_add_tail_rcu(&call->link, &rxnet->calls); 401 spin_unlock(&rxnet->call_lock); 402 403 /* From this point on, the call is protected by its own lock. */ 404 release_sock(&rx->sk); 405 406 /* Set up or get a connection record and set the protocol parameters, 407 * including channel number and call ID. 408 */ 409 ret = rxrpc_connect_call(call, gfp); 410 if (ret < 0) 411 goto error_attached_to_socket; 412 413 _leave(" = %p [new]", call); 414 return call; 415 416 /* We unexpectedly found the user ID in the list after taking 417 * the call_lock. This shouldn't happen unless the user races 418 * with itself and tries to add the same user ID twice at the 419 * same time in different threads. 420 */ 421 error_dup_user_ID: 422 write_unlock(&rx->call_lock); 423 release_sock(&rx->sk); 424 rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST); 425 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0, 426 rxrpc_call_see_userid_exists); 427 mutex_unlock(&call->user_mutex); 428 rxrpc_put_call(call, rxrpc_call_put_userid_exists); 429 _leave(" = -EEXIST"); 430 return ERR_PTR(-EEXIST); 431 432 /* We got an error, but the call is attached to the socket and is in 433 * need of release. However, we might now race with recvmsg() when it 434 * completion notifies the socket. Return 0 from sys_sendmsg() and 435 * leave the error to recvmsg() to deal with. 436 */ 437 error_attached_to_socket: 438 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret, 439 rxrpc_call_see_connect_failed); 440 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret); 441 _leave(" = c=%08x [err]", call->debug_id); 442 return call; 443 } 444 445 /* 446 * Set up an incoming call. call->conn points to the connection. 447 * This is called in BH context and isn't allowed to fail. 448 */ 449 void rxrpc_incoming_call(struct rxrpc_sock *rx, 450 struct rxrpc_call *call, 451 struct sk_buff *skb) 452 { 453 struct rxrpc_connection *conn = call->conn; 454 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 455 u32 chan; 456 457 _enter(",%d", call->conn->debug_id); 458 459 rcu_assign_pointer(call->socket, rx); 460 call->call_id = sp->hdr.callNumber; 461 call->dest_srx.srx_service = sp->hdr.serviceId; 462 call->cid = sp->hdr.cid; 463 call->cong_tstamp = skb->tstamp; 464 465 __set_bit(RXRPC_CALL_EXPOSED, &call->flags); 466 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); 467 468 spin_lock(&conn->state_lock); 469 470 switch (conn->state) { 471 case RXRPC_CONN_SERVICE_UNSECURED: 472 case RXRPC_CONN_SERVICE_CHALLENGING: 473 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING); 474 break; 475 case RXRPC_CONN_SERVICE: 476 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST); 477 break; 478 479 case RXRPC_CONN_ABORTED: 480 rxrpc_set_call_completion(call, conn->completion, 481 conn->abort_code, conn->error); 482 break; 483 default: 484 BUG(); 485 } 486 487 rxrpc_get_call(call, rxrpc_call_get_io_thread); 488 489 /* Set the channel for this call. We don't get channel_lock as we're 490 * only defending against the data_ready handler (which we're called 491 * from) and the RESPONSE packet parser (which is only really 492 * interested in call_counter and can cope with a disagreement with the 493 * call pointer). 494 */ 495 chan = sp->hdr.cid & RXRPC_CHANNELMASK; 496 conn->channels[chan].call_counter = call->call_id; 497 conn->channels[chan].call_id = call->call_id; 498 conn->channels[chan].call = call; 499 spin_unlock(&conn->state_lock); 500 501 spin_lock(&conn->peer->lock); 502 hlist_add_head(&call->error_link, &conn->peer->error_targets); 503 spin_unlock(&conn->peer->lock); 504 505 rxrpc_start_call_timer(call); 506 _leave(""); 507 } 508 509 /* 510 * Note the re-emergence of a call. 511 */ 512 void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 513 { 514 if (call) { 515 int r = refcount_read(&call->ref); 516 517 trace_rxrpc_call(call->debug_id, r, 0, why); 518 } 519 } 520 521 struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call, 522 enum rxrpc_call_trace why) 523 { 524 int r; 525 526 if (!call || !__refcount_inc_not_zero(&call->ref, &r)) 527 return NULL; 528 trace_rxrpc_call(call->debug_id, r + 1, 0, why); 529 return call; 530 } 531 532 /* 533 * Note the addition of a ref on a call. 534 */ 535 void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 536 { 537 int r; 538 539 __refcount_inc(&call->ref, &r); 540 trace_rxrpc_call(call->debug_id, r + 1, 0, why); 541 } 542 543 /* 544 * Clean up the Rx skb ring. 545 */ 546 static void rxrpc_cleanup_ring(struct rxrpc_call *call) 547 { 548 rxrpc_purge_queue(&call->recvmsg_queue); 549 rxrpc_purge_queue(&call->rx_oos_queue); 550 } 551 552 /* 553 * Detach a call from its owning socket. 554 */ 555 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call) 556 { 557 struct rxrpc_connection *conn = call->conn; 558 bool put = false, putu = false; 559 560 _enter("{%d,%d}", call->debug_id, refcount_read(&call->ref)); 561 562 trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 563 call->flags, rxrpc_call_see_release); 564 565 if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags)) 566 BUG(); 567 568 rxrpc_put_call_slot(call); 569 570 /* Make sure we don't get any more notifications */ 571 spin_lock(&rx->recvmsg_lock); 572 573 if (!list_empty(&call->recvmsg_link)) { 574 _debug("unlinking once-pending call %p { e=%lx f=%lx }", 575 call, call->events, call->flags); 576 list_del(&call->recvmsg_link); 577 put = true; 578 } 579 580 /* list_empty() must return false in rxrpc_notify_socket() */ 581 call->recvmsg_link.next = NULL; 582 call->recvmsg_link.prev = NULL; 583 584 spin_unlock(&rx->recvmsg_lock); 585 if (put) 586 rxrpc_put_call(call, rxrpc_call_put_unnotify); 587 588 write_lock(&rx->call_lock); 589 590 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { 591 rb_erase(&call->sock_node, &rx->calls); 592 memset(&call->sock_node, 0xdd, sizeof(call->sock_node)); 593 putu = true; 594 } 595 596 list_del(&call->sock_link); 597 write_unlock(&rx->call_lock); 598 599 _debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn); 600 601 if (putu) 602 rxrpc_put_call(call, rxrpc_call_put_userid); 603 604 _leave(""); 605 } 606 607 /* 608 * release all the calls associated with a socket 609 */ 610 void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx) 611 { 612 struct rxrpc_call *call; 613 614 _enter("%p", rx); 615 616 while (!list_empty(&rx->to_be_accepted)) { 617 call = list_entry(rx->to_be_accepted.next, 618 struct rxrpc_call, accept_link); 619 list_del(&call->accept_link); 620 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, 621 rxrpc_abort_call_sock_release_tba); 622 rxrpc_put_call(call, rxrpc_call_put_release_sock_tba); 623 } 624 625 while (!list_empty(&rx->sock_calls)) { 626 call = list_entry(rx->sock_calls.next, 627 struct rxrpc_call, sock_link); 628 rxrpc_get_call(call, rxrpc_call_get_release_sock); 629 rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET, 630 rxrpc_abort_call_sock_release); 631 rxrpc_release_call(rx, call); 632 rxrpc_put_call(call, rxrpc_call_put_release_sock); 633 } 634 635 _leave(""); 636 } 637 638 /* 639 * release a call 640 */ 641 void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why) 642 { 643 struct rxrpc_net *rxnet = call->rxnet; 644 unsigned int debug_id = call->debug_id; 645 bool dead; 646 int r; 647 648 ASSERT(call != NULL); 649 650 dead = __refcount_dec_and_test(&call->ref, &r); 651 trace_rxrpc_call(debug_id, r - 1, 0, why); 652 if (dead) { 653 ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE); 654 655 if (!list_empty(&call->link)) { 656 spin_lock(&rxnet->call_lock); 657 list_del_init(&call->link); 658 spin_unlock(&rxnet->call_lock); 659 } 660 661 rxrpc_cleanup_call(call); 662 } 663 } 664 665 /* 666 * Free up the call under RCU. 667 */ 668 static void rxrpc_rcu_free_call(struct rcu_head *rcu) 669 { 670 struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu); 671 struct rxrpc_net *rxnet = READ_ONCE(call->rxnet); 672 673 kmem_cache_free(rxrpc_call_jar, call); 674 if (atomic_dec_and_test(&rxnet->nr_calls)) 675 wake_up_var(&rxnet->nr_calls); 676 } 677 678 /* 679 * Final call destruction - but must be done in process context. 680 */ 681 static void rxrpc_destroy_call(struct work_struct *work) 682 { 683 struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer); 684 struct rxrpc_txbuf *txb; 685 686 del_timer_sync(&call->timer); 687 688 rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack); 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