1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Maintain an RxRPC server socket to do AFS communications through 3 * 4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/sched/signal.h> 10 11 #include <net/sock.h> 12 #include <net/af_rxrpc.h> 13 #include "internal.h" 14 #include "afs_cm.h" 15 #include "protocol_yfs.h" 16 17 struct workqueue_struct *afs_async_calls; 18 19 static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); 20 static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); 21 static void afs_delete_async_call(struct work_struct *); 22 static void afs_process_async_call(struct work_struct *); 23 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long); 24 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long); 25 static int afs_deliver_cm_op_id(struct afs_call *); 26 27 /* asynchronous incoming call initial processing */ 28 static const struct afs_call_type afs_RXCMxxxx = { 29 .name = "CB.xxxx", 30 .deliver = afs_deliver_cm_op_id, 31 }; 32 33 /* 34 * open an RxRPC socket and bind it to be a server for callback notifications 35 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 36 */ 37 int afs_open_socket(struct afs_net *net) 38 { 39 struct sockaddr_rxrpc srx; 40 struct socket *socket; 41 unsigned int min_level; 42 int ret; 43 44 _enter(""); 45 46 ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket); 47 if (ret < 0) 48 goto error_1; 49 50 socket->sk->sk_allocation = GFP_NOFS; 51 52 /* bind the callback manager's address to make this a server socket */ 53 memset(&srx, 0, sizeof(srx)); 54 srx.srx_family = AF_RXRPC; 55 srx.srx_service = CM_SERVICE; 56 srx.transport_type = SOCK_DGRAM; 57 srx.transport_len = sizeof(srx.transport.sin6); 58 srx.transport.sin6.sin6_family = AF_INET6; 59 srx.transport.sin6.sin6_port = htons(AFS_CM_PORT); 60 61 min_level = RXRPC_SECURITY_ENCRYPT; 62 ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_MIN_SECURITY_LEVEL, 63 (void *)&min_level, sizeof(min_level)); 64 if (ret < 0) 65 goto error_2; 66 67 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 68 if (ret == -EADDRINUSE) { 69 srx.transport.sin6.sin6_port = 0; 70 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 71 } 72 if (ret < 0) 73 goto error_2; 74 75 srx.srx_service = YFS_CM_SERVICE; 76 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 77 if (ret < 0) 78 goto error_2; 79 80 /* Ideally, we'd turn on service upgrade here, but we can't because 81 * OpenAFS is buggy and leaks the userStatus field from packet to 82 * packet and between FS packets and CB packets - so if we try to do an 83 * upgrade on an FS packet, OpenAFS will leak that into the CB packet 84 * it sends back to us. 85 */ 86 87 rxrpc_kernel_new_call_notification(socket, afs_rx_new_call, 88 afs_rx_discard_new_call); 89 90 ret = kernel_listen(socket, INT_MAX); 91 if (ret < 0) 92 goto error_2; 93 94 net->socket = socket; 95 afs_charge_preallocation(&net->charge_preallocation_work); 96 _leave(" = 0"); 97 return 0; 98 99 error_2: 100 sock_release(socket); 101 error_1: 102 _leave(" = %d", ret); 103 return ret; 104 } 105 106 /* 107 * close the RxRPC socket AFS was using 108 */ 109 void afs_close_socket(struct afs_net *net) 110 { 111 _enter(""); 112 113 kernel_listen(net->socket, 0); 114 flush_workqueue(afs_async_calls); 115 116 if (net->spare_incoming_call) { 117 afs_put_call(net->spare_incoming_call); 118 net->spare_incoming_call = NULL; 119 } 120 121 _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls)); 122 wait_var_event(&net->nr_outstanding_calls, 123 !atomic_read(&net->nr_outstanding_calls)); 124 _debug("no outstanding calls"); 125 126 kernel_sock_shutdown(net->socket, SHUT_RDWR); 127 flush_workqueue(afs_async_calls); 128 sock_release(net->socket); 129 130 _debug("dework"); 131 _leave(""); 132 } 133 134 /* 135 * Allocate a call. 136 */ 137 static struct afs_call *afs_alloc_call(struct afs_net *net, 138 const struct afs_call_type *type, 139 gfp_t gfp) 140 { 141 struct afs_call *call; 142 int o; 143 144 call = kzalloc(sizeof(*call), gfp); 145 if (!call) 146 return NULL; 147 148 call->type = type; 149 call->net = net; 150 call->debug_id = atomic_inc_return(&rxrpc_debug_id); 151 atomic_set(&call->usage, 1); 152 INIT_WORK(&call->async_work, afs_process_async_call); 153 init_waitqueue_head(&call->waitq); 154 spin_lock_init(&call->state_lock); 155 call->_iter = &call->iter; 156 157 o = atomic_inc_return(&net->nr_outstanding_calls); 158 trace_afs_call(call, afs_call_trace_alloc, 1, o, 159 __builtin_return_address(0)); 160 return call; 161 } 162 163 /* 164 * Dispose of a reference on a call. 165 */ 166 void afs_put_call(struct afs_call *call) 167 { 168 struct afs_net *net = call->net; 169 int n = atomic_dec_return(&call->usage); 170 int o = atomic_read(&net->nr_outstanding_calls); 171 172 trace_afs_call(call, afs_call_trace_put, n + 1, o, 173 __builtin_return_address(0)); 174 175 ASSERTCMP(n, >=, 0); 176 if (n == 0) { 177 ASSERT(!work_pending(&call->async_work)); 178 ASSERT(call->type->name != NULL); 179 180 if (call->rxcall) { 181 rxrpc_kernel_end_call(net->socket, call->rxcall); 182 call->rxcall = NULL; 183 } 184 if (call->type->destructor) 185 call->type->destructor(call); 186 187 afs_put_server(call->net, call->server); 188 afs_put_cb_interest(call->net, call->cbi); 189 afs_put_addrlist(call->alist); 190 kfree(call->request); 191 192 trace_afs_call(call, afs_call_trace_free, 0, o, 193 __builtin_return_address(0)); 194 kfree(call); 195 196 o = atomic_dec_return(&net->nr_outstanding_calls); 197 if (o == 0) 198 wake_up_var(&net->nr_outstanding_calls); 199 } 200 } 201 202 static struct afs_call *afs_get_call(struct afs_call *call, 203 enum afs_call_trace why) 204 { 205 int u = atomic_inc_return(&call->usage); 206 207 trace_afs_call(call, why, u, 208 atomic_read(&call->net->nr_outstanding_calls), 209 __builtin_return_address(0)); 210 return call; 211 } 212 213 /* 214 * Queue the call for actual work. 215 */ 216 static void afs_queue_call_work(struct afs_call *call) 217 { 218 if (call->type->work) { 219 INIT_WORK(&call->work, call->type->work); 220 221 afs_get_call(call, afs_call_trace_work); 222 if (!queue_work(afs_wq, &call->work)) 223 afs_put_call(call); 224 } 225 } 226 227 /* 228 * allocate a call with flat request and reply buffers 229 */ 230 struct afs_call *afs_alloc_flat_call(struct afs_net *net, 231 const struct afs_call_type *type, 232 size_t request_size, size_t reply_max) 233 { 234 struct afs_call *call; 235 236 call = afs_alloc_call(net, type, GFP_NOFS); 237 if (!call) 238 goto nomem_call; 239 240 if (request_size) { 241 call->request_size = request_size; 242 call->request = kmalloc(request_size, GFP_NOFS); 243 if (!call->request) 244 goto nomem_free; 245 } 246 247 if (reply_max) { 248 call->reply_max = reply_max; 249 call->buffer = kmalloc(reply_max, GFP_NOFS); 250 if (!call->buffer) 251 goto nomem_free; 252 } 253 254 afs_extract_to_buf(call, call->reply_max); 255 call->operation_ID = type->op; 256 init_waitqueue_head(&call->waitq); 257 return call; 258 259 nomem_free: 260 afs_put_call(call); 261 nomem_call: 262 return NULL; 263 } 264 265 /* 266 * clean up a call with flat buffer 267 */ 268 void afs_flat_call_destructor(struct afs_call *call) 269 { 270 _enter(""); 271 272 kfree(call->request); 273 call->request = NULL; 274 kfree(call->buffer); 275 call->buffer = NULL; 276 } 277 278 #define AFS_BVEC_MAX 8 279 280 /* 281 * Load the given bvec with the next few pages. 282 */ 283 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg, 284 struct bio_vec *bv, pgoff_t first, pgoff_t last, 285 unsigned offset) 286 { 287 struct page *pages[AFS_BVEC_MAX]; 288 unsigned int nr, n, i, to, bytes = 0; 289 290 nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX); 291 n = find_get_pages_contig(call->mapping, first, nr, pages); 292 ASSERTCMP(n, ==, nr); 293 294 msg->msg_flags |= MSG_MORE; 295 for (i = 0; i < nr; i++) { 296 to = PAGE_SIZE; 297 if (first + i >= last) { 298 to = call->last_to; 299 msg->msg_flags &= ~MSG_MORE; 300 } 301 bv[i].bv_page = pages[i]; 302 bv[i].bv_len = to - offset; 303 bv[i].bv_offset = offset; 304 bytes += to - offset; 305 offset = 0; 306 } 307 308 iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes); 309 } 310 311 /* 312 * Advance the AFS call state when the RxRPC call ends the transmit phase. 313 */ 314 static void afs_notify_end_request_tx(struct sock *sock, 315 struct rxrpc_call *rxcall, 316 unsigned long call_user_ID) 317 { 318 struct afs_call *call = (struct afs_call *)call_user_ID; 319 320 afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY); 321 } 322 323 /* 324 * attach the data from a bunch of pages on an inode to a call 325 */ 326 static int afs_send_pages(struct afs_call *call, struct msghdr *msg) 327 { 328 struct bio_vec bv[AFS_BVEC_MAX]; 329 unsigned int bytes, nr, loop, offset; 330 pgoff_t first = call->first, last = call->last; 331 int ret; 332 333 offset = call->first_offset; 334 call->first_offset = 0; 335 336 do { 337 afs_load_bvec(call, msg, bv, first, last, offset); 338 trace_afs_send_pages(call, msg, first, last, offset); 339 340 offset = 0; 341 bytes = msg->msg_iter.count; 342 nr = msg->msg_iter.nr_segs; 343 344 ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg, 345 bytes, afs_notify_end_request_tx); 346 for (loop = 0; loop < nr; loop++) 347 put_page(bv[loop].bv_page); 348 if (ret < 0) 349 break; 350 351 first += nr; 352 } while (first <= last); 353 354 trace_afs_sent_pages(call, call->first, last, first, ret); 355 return ret; 356 } 357 358 /* 359 * Initiate a call and synchronously queue up the parameters for dispatch. Any 360 * error is stored into the call struct, which the caller must check for. 361 */ 362 void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) 363 { 364 struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index]; 365 struct rxrpc_call *rxcall; 366 struct msghdr msg; 367 struct kvec iov[1]; 368 s64 tx_total_len; 369 int ret; 370 371 _enter(",{%pISp},", &srx->transport); 372 373 ASSERT(call->type != NULL); 374 ASSERT(call->type->name != NULL); 375 376 _debug("____MAKE %p{%s,%x} [%d]____", 377 call, call->type->name, key_serial(call->key), 378 atomic_read(&call->net->nr_outstanding_calls)); 379 380 call->addr_ix = ac->index; 381 call->alist = afs_get_addrlist(ac->alist); 382 383 /* Work out the length we're going to transmit. This is awkward for 384 * calls such as FS.StoreData where there's an extra injection of data 385 * after the initial fixed part. 386 */ 387 tx_total_len = call->request_size; 388 if (call->send_pages) { 389 if (call->last == call->first) { 390 tx_total_len += call->last_to - call->first_offset; 391 } else { 392 /* It looks mathematically like you should be able to 393 * combine the following lines with the ones above, but 394 * unsigned arithmetic is fun when it wraps... 395 */ 396 tx_total_len += PAGE_SIZE - call->first_offset; 397 tx_total_len += call->last_to; 398 tx_total_len += (call->last - call->first - 1) * PAGE_SIZE; 399 } 400 } 401 402 /* If the call is going to be asynchronous, we need an extra ref for 403 * the call to hold itself so the caller need not hang on to its ref. 404 */ 405 if (call->async) 406 afs_get_call(call, afs_call_trace_get); 407 408 /* create a call */ 409 rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key, 410 (unsigned long)call, 411 tx_total_len, gfp, 412 (call->async ? 413 afs_wake_up_async_call : 414 afs_wake_up_call_waiter), 415 call->upgrade, 416 call->intr, 417 call->debug_id); 418 if (IS_ERR(rxcall)) { 419 ret = PTR_ERR(rxcall); 420 call->error = ret; 421 goto error_kill_call; 422 } 423 424 call->rxcall = rxcall; 425 426 if (call->max_lifespan) 427 rxrpc_kernel_set_max_life(call->net->socket, rxcall, 428 call->max_lifespan); 429 430 /* send the request */ 431 iov[0].iov_base = call->request; 432 iov[0].iov_len = call->request_size; 433 434 msg.msg_name = NULL; 435 msg.msg_namelen = 0; 436 iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size); 437 msg.msg_control = NULL; 438 msg.msg_controllen = 0; 439 msg.msg_flags = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0); 440 441 ret = rxrpc_kernel_send_data(call->net->socket, rxcall, 442 &msg, call->request_size, 443 afs_notify_end_request_tx); 444 if (ret < 0) 445 goto error_do_abort; 446 447 if (call->send_pages) { 448 ret = afs_send_pages(call, &msg); 449 if (ret < 0) 450 goto error_do_abort; 451 } 452 453 /* Note that at this point, we may have received the reply or an abort 454 * - and an asynchronous call may already have completed. 455 * 456 * afs_wait_for_call_to_complete(call, ac) 457 * must be called to synchronously clean up. 458 */ 459 return; 460 461 error_do_abort: 462 if (ret != -ECONNABORTED) { 463 rxrpc_kernel_abort_call(call->net->socket, rxcall, 464 RX_USER_ABORT, ret, "KSD"); 465 } else { 466 iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0); 467 rxrpc_kernel_recv_data(call->net->socket, rxcall, 468 &msg.msg_iter, false, 469 &call->abort_code, &call->service_id); 470 ac->abort_code = call->abort_code; 471 ac->responded = true; 472 } 473 call->error = ret; 474 trace_afs_call_done(call); 475 error_kill_call: 476 if (call->type->done) 477 call->type->done(call); 478 479 /* We need to dispose of the extra ref we grabbed for an async call. 480 * The call, however, might be queued on afs_async_calls and we need to 481 * make sure we don't get any more notifications that might requeue it. 482 */ 483 if (call->rxcall) { 484 rxrpc_kernel_end_call(call->net->socket, call->rxcall); 485 call->rxcall = NULL; 486 } 487 if (call->async) { 488 if (cancel_work_sync(&call->async_work)) 489 afs_put_call(call); 490 afs_put_call(call); 491 } 492 493 ac->error = ret; 494 call->state = AFS_CALL_COMPLETE; 495 _leave(" = %d", ret); 496 } 497 498 /* 499 * deliver messages to a call 500 */ 501 static void afs_deliver_to_call(struct afs_call *call) 502 { 503 enum afs_call_state state; 504 u32 abort_code, remote_abort = 0; 505 int ret; 506 507 _enter("%s", call->type->name); 508 509 while (state = READ_ONCE(call->state), 510 state == AFS_CALL_CL_AWAIT_REPLY || 511 state == AFS_CALL_SV_AWAIT_OP_ID || 512 state == AFS_CALL_SV_AWAIT_REQUEST || 513 state == AFS_CALL_SV_AWAIT_ACK 514 ) { 515 if (state == AFS_CALL_SV_AWAIT_ACK) { 516 iov_iter_kvec(&call->iter, READ, NULL, 0, 0); 517 ret = rxrpc_kernel_recv_data(call->net->socket, 518 call->rxcall, &call->iter, 519 false, &remote_abort, 520 &call->service_id); 521 trace_afs_receive_data(call, &call->iter, false, ret); 522 523 if (ret == -EINPROGRESS || ret == -EAGAIN) 524 return; 525 if (ret < 0 || ret == 1) { 526 if (ret == 1) 527 ret = 0; 528 goto call_complete; 529 } 530 return; 531 } 532 533 if (!call->have_reply_time && 534 rxrpc_kernel_get_reply_time(call->net->socket, 535 call->rxcall, 536 &call->reply_time)) 537 call->have_reply_time = true; 538 539 ret = call->type->deliver(call); 540 state = READ_ONCE(call->state); 541 switch (ret) { 542 case 0: 543 afs_queue_call_work(call); 544 if (state == AFS_CALL_CL_PROC_REPLY) { 545 if (call->cbi) 546 set_bit(AFS_SERVER_FL_MAY_HAVE_CB, 547 &call->cbi->server->flags); 548 goto call_complete; 549 } 550 ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY); 551 goto done; 552 case -EINPROGRESS: 553 case -EAGAIN: 554 goto out; 555 case -ECONNABORTED: 556 ASSERTCMP(state, ==, AFS_CALL_COMPLETE); 557 goto done; 558 case -ENOTSUPP: 559 abort_code = RXGEN_OPCODE; 560 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 561 abort_code, ret, "KIV"); 562 goto local_abort; 563 case -EIO: 564 pr_err("kAFS: Call %u in bad state %u\n", 565 call->debug_id, state); 566 /* Fall through */ 567 case -ENODATA: 568 case -EBADMSG: 569 case -EMSGSIZE: 570 abort_code = RXGEN_CC_UNMARSHAL; 571 if (state != AFS_CALL_CL_AWAIT_REPLY) 572 abort_code = RXGEN_SS_UNMARSHAL; 573 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 574 abort_code, ret, "KUM"); 575 goto local_abort; 576 default: 577 abort_code = RX_USER_ABORT; 578 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 579 abort_code, ret, "KER"); 580 goto local_abort; 581 } 582 } 583 584 done: 585 if (call->type->done) 586 call->type->done(call); 587 if (state == AFS_CALL_COMPLETE && call->incoming) 588 afs_put_call(call); 589 out: 590 _leave(""); 591 return; 592 593 local_abort: 594 abort_code = 0; 595 call_complete: 596 afs_set_call_complete(call, ret, remote_abort); 597 state = AFS_CALL_COMPLETE; 598 goto done; 599 } 600 601 /* 602 * Wait synchronously for a call to complete and clean up the call struct. 603 */ 604 long afs_wait_for_call_to_complete(struct afs_call *call, 605 struct afs_addr_cursor *ac) 606 { 607 signed long rtt2, timeout; 608 long ret; 609 bool stalled = false; 610 u64 rtt; 611 u32 life, last_life; 612 bool rxrpc_complete = false; 613 614 DECLARE_WAITQUEUE(myself, current); 615 616 _enter(""); 617 618 ret = call->error; 619 if (ret < 0) 620 goto out; 621 622 rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall); 623 rtt2 = nsecs_to_jiffies64(rtt) * 2; 624 if (rtt2 < 2) 625 rtt2 = 2; 626 627 timeout = rtt2; 628 rxrpc_kernel_check_life(call->net->socket, call->rxcall, &last_life); 629 630 add_wait_queue(&call->waitq, &myself); 631 for (;;) { 632 set_current_state(TASK_UNINTERRUPTIBLE); 633 634 /* deliver any messages that are in the queue */ 635 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) && 636 call->need_attention) { 637 call->need_attention = false; 638 __set_current_state(TASK_RUNNING); 639 afs_deliver_to_call(call); 640 continue; 641 } 642 643 if (afs_check_call_state(call, AFS_CALL_COMPLETE)) 644 break; 645 646 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall, &life)) { 647 /* rxrpc terminated the call. */ 648 rxrpc_complete = true; 649 break; 650 } 651 652 if (call->intr && timeout == 0 && 653 life == last_life && signal_pending(current)) { 654 if (stalled) 655 break; 656 __set_current_state(TASK_RUNNING); 657 rxrpc_kernel_probe_life(call->net->socket, call->rxcall); 658 timeout = rtt2; 659 stalled = true; 660 continue; 661 } 662 663 if (life != last_life) { 664 timeout = rtt2; 665 last_life = life; 666 stalled = false; 667 } 668 669 timeout = schedule_timeout(timeout); 670 } 671 672 remove_wait_queue(&call->waitq, &myself); 673 __set_current_state(TASK_RUNNING); 674 675 if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) { 676 if (rxrpc_complete) { 677 afs_set_call_complete(call, call->error, call->abort_code); 678 } else { 679 /* Kill off the call if it's still live. */ 680 _debug("call interrupted"); 681 if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 682 RX_USER_ABORT, -EINTR, "KWI")) 683 afs_set_call_complete(call, -EINTR, 0); 684 } 685 } 686 687 spin_lock_bh(&call->state_lock); 688 ac->abort_code = call->abort_code; 689 ac->error = call->error; 690 spin_unlock_bh(&call->state_lock); 691 692 ret = ac->error; 693 switch (ret) { 694 case 0: 695 ret = call->ret0; 696 call->ret0 = 0; 697 698 /* Fall through */ 699 case -ECONNABORTED: 700 ac->responded = true; 701 break; 702 } 703 704 out: 705 _debug("call complete"); 706 afs_put_call(call); 707 _leave(" = %p", (void *)ret); 708 return ret; 709 } 710 711 /* 712 * wake up a waiting call 713 */ 714 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, 715 unsigned long call_user_ID) 716 { 717 struct afs_call *call = (struct afs_call *)call_user_ID; 718 719 call->need_attention = true; 720 wake_up(&call->waitq); 721 } 722 723 /* 724 * wake up an asynchronous call 725 */ 726 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, 727 unsigned long call_user_ID) 728 { 729 struct afs_call *call = (struct afs_call *)call_user_ID; 730 int u; 731 732 trace_afs_notify_call(rxcall, call); 733 call->need_attention = true; 734 735 u = atomic_fetch_add_unless(&call->usage, 1, 0); 736 if (u != 0) { 737 trace_afs_call(call, afs_call_trace_wake, u, 738 atomic_read(&call->net->nr_outstanding_calls), 739 __builtin_return_address(0)); 740 741 if (!queue_work(afs_async_calls, &call->async_work)) 742 afs_put_call(call); 743 } 744 } 745 746 /* 747 * Delete an asynchronous call. The work item carries a ref to the call struct 748 * that we need to release. 749 */ 750 static void afs_delete_async_call(struct work_struct *work) 751 { 752 struct afs_call *call = container_of(work, struct afs_call, async_work); 753 754 _enter(""); 755 756 afs_put_call(call); 757 758 _leave(""); 759 } 760 761 /* 762 * Perform I/O processing on an asynchronous call. The work item carries a ref 763 * to the call struct that we either need to release or to pass on. 764 */ 765 static void afs_process_async_call(struct work_struct *work) 766 { 767 struct afs_call *call = container_of(work, struct afs_call, async_work); 768 769 _enter(""); 770 771 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 772 call->need_attention = false; 773 afs_deliver_to_call(call); 774 } 775 776 if (call->state == AFS_CALL_COMPLETE) { 777 /* We have two refs to release - one from the alloc and one 778 * queued with the work item - and we can't just deallocate the 779 * call because the work item may be queued again. 780 */ 781 call->async_work.func = afs_delete_async_call; 782 if (!queue_work(afs_async_calls, &call->async_work)) 783 afs_put_call(call); 784 } 785 786 afs_put_call(call); 787 _leave(""); 788 } 789 790 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) 791 { 792 struct afs_call *call = (struct afs_call *)user_call_ID; 793 794 call->rxcall = rxcall; 795 } 796 797 /* 798 * Charge the incoming call preallocation. 799 */ 800 void afs_charge_preallocation(struct work_struct *work) 801 { 802 struct afs_net *net = 803 container_of(work, struct afs_net, charge_preallocation_work); 804 struct afs_call *call = net->spare_incoming_call; 805 806 for (;;) { 807 if (!call) { 808 call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL); 809 if (!call) 810 break; 811 812 call->async = true; 813 call->state = AFS_CALL_SV_AWAIT_OP_ID; 814 init_waitqueue_head(&call->waitq); 815 afs_extract_to_tmp(call); 816 } 817 818 if (rxrpc_kernel_charge_accept(net->socket, 819 afs_wake_up_async_call, 820 afs_rx_attach, 821 (unsigned long)call, 822 GFP_KERNEL, 823 call->debug_id) < 0) 824 break; 825 call = NULL; 826 } 827 net->spare_incoming_call = call; 828 } 829 830 /* 831 * Discard a preallocated call when a socket is shut down. 832 */ 833 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, 834 unsigned long user_call_ID) 835 { 836 struct afs_call *call = (struct afs_call *)user_call_ID; 837 838 call->rxcall = NULL; 839 afs_put_call(call); 840 } 841 842 /* 843 * Notification of an incoming call. 844 */ 845 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, 846 unsigned long user_call_ID) 847 { 848 struct afs_net *net = afs_sock2net(sk); 849 850 queue_work(afs_wq, &net->charge_preallocation_work); 851 } 852 853 /* 854 * Grab the operation ID from an incoming cache manager call. The socket 855 * buffer is discarded on error or if we don't yet have sufficient data. 856 */ 857 static int afs_deliver_cm_op_id(struct afs_call *call) 858 { 859 int ret; 860 861 _enter("{%zu}", iov_iter_count(call->_iter)); 862 863 /* the operation ID forms the first four bytes of the request data */ 864 ret = afs_extract_data(call, true); 865 if (ret < 0) 866 return ret; 867 868 call->operation_ID = ntohl(call->tmp); 869 afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST); 870 871 /* ask the cache manager to route the call (it'll change the call type 872 * if successful) */ 873 if (!afs_cm_incoming_call(call)) 874 return -ENOTSUPP; 875 876 trace_afs_cb_call(call); 877 878 /* pass responsibility for the remainer of this message off to the 879 * cache manager op */ 880 return call->type->deliver(call); 881 } 882 883 /* 884 * Advance the AFS call state when an RxRPC service call ends the transmit 885 * phase. 886 */ 887 static void afs_notify_end_reply_tx(struct sock *sock, 888 struct rxrpc_call *rxcall, 889 unsigned long call_user_ID) 890 { 891 struct afs_call *call = (struct afs_call *)call_user_ID; 892 893 afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK); 894 } 895 896 /* 897 * send an empty reply 898 */ 899 void afs_send_empty_reply(struct afs_call *call) 900 { 901 struct afs_net *net = call->net; 902 struct msghdr msg; 903 904 _enter(""); 905 906 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0); 907 908 msg.msg_name = NULL; 909 msg.msg_namelen = 0; 910 iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0); 911 msg.msg_control = NULL; 912 msg.msg_controllen = 0; 913 msg.msg_flags = 0; 914 915 switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0, 916 afs_notify_end_reply_tx)) { 917 case 0: 918 _leave(" [replied]"); 919 return; 920 921 case -ENOMEM: 922 _debug("oom"); 923 rxrpc_kernel_abort_call(net->socket, call->rxcall, 924 RX_USER_ABORT, -ENOMEM, "KOO"); 925 /* Fall through */ 926 default: 927 _leave(" [error]"); 928 return; 929 } 930 } 931 932 /* 933 * send a simple reply 934 */ 935 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 936 { 937 struct afs_net *net = call->net; 938 struct msghdr msg; 939 struct kvec iov[1]; 940 int n; 941 942 _enter(""); 943 944 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len); 945 946 iov[0].iov_base = (void *) buf; 947 iov[0].iov_len = len; 948 msg.msg_name = NULL; 949 msg.msg_namelen = 0; 950 iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); 951 msg.msg_control = NULL; 952 msg.msg_controllen = 0; 953 msg.msg_flags = 0; 954 955 n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len, 956 afs_notify_end_reply_tx); 957 if (n >= 0) { 958 /* Success */ 959 _leave(" [replied]"); 960 return; 961 } 962 963 if (n == -ENOMEM) { 964 _debug("oom"); 965 rxrpc_kernel_abort_call(net->socket, call->rxcall, 966 RX_USER_ABORT, -ENOMEM, "KOO"); 967 } 968 _leave(" [error]"); 969 } 970 971 /* 972 * Extract a piece of data from the received data socket buffers. 973 */ 974 int afs_extract_data(struct afs_call *call, bool want_more) 975 { 976 struct afs_net *net = call->net; 977 struct iov_iter *iter = call->_iter; 978 enum afs_call_state state; 979 u32 remote_abort = 0; 980 int ret; 981 982 _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more); 983 984 ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter, 985 want_more, &remote_abort, 986 &call->service_id); 987 if (ret == 0 || ret == -EAGAIN) 988 return ret; 989 990 state = READ_ONCE(call->state); 991 if (ret == 1) { 992 switch (state) { 993 case AFS_CALL_CL_AWAIT_REPLY: 994 afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY); 995 break; 996 case AFS_CALL_SV_AWAIT_REQUEST: 997 afs_set_call_state(call, state, AFS_CALL_SV_REPLYING); 998 break; 999 case AFS_CALL_COMPLETE: 1000 kdebug("prem complete %d", call->error); 1001 return afs_io_error(call, afs_io_error_extract); 1002 default: 1003 break; 1004 } 1005 return 0; 1006 } 1007 1008 afs_set_call_complete(call, ret, remote_abort); 1009 return ret; 1010 } 1011 1012 /* 1013 * Log protocol error production. 1014 */ 1015 noinline int afs_protocol_error(struct afs_call *call, int error, 1016 enum afs_eproto_cause cause) 1017 { 1018 trace_afs_protocol_error(call, error, cause); 1019 return error; 1020 } 1021