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_process_async_call(struct work_struct *); 22 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long); 23 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long); 24 static int afs_deliver_cm_op_id(struct afs_call *); 25 26 /* asynchronous incoming call initial processing */ 27 static const struct afs_call_type afs_RXCMxxxx = { 28 .name = "CB.xxxx", 29 .deliver = afs_deliver_cm_op_id, 30 }; 31 32 /* 33 * open an RxRPC socket and bind it to be a server for callback notifications 34 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 35 */ 36 int afs_open_socket(struct afs_net *net) 37 { 38 struct sockaddr_rxrpc srx; 39 struct socket *socket; 40 int ret; 41 42 _enter(""); 43 44 ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket); 45 if (ret < 0) 46 goto error_1; 47 48 socket->sk->sk_allocation = GFP_NOFS; 49 50 /* bind the callback manager's address to make this a server socket */ 51 memset(&srx, 0, sizeof(srx)); 52 srx.srx_family = AF_RXRPC; 53 srx.srx_service = CM_SERVICE; 54 srx.transport_type = SOCK_DGRAM; 55 srx.transport_len = sizeof(srx.transport.sin6); 56 srx.transport.sin6.sin6_family = AF_INET6; 57 srx.transport.sin6.sin6_port = htons(AFS_CM_PORT); 58 59 ret = rxrpc_sock_set_min_security_level(socket->sk, 60 RXRPC_SECURITY_ENCRYPT); 61 if (ret < 0) 62 goto error_2; 63 64 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 65 if (ret == -EADDRINUSE) { 66 srx.transport.sin6.sin6_port = 0; 67 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 68 } 69 if (ret < 0) 70 goto error_2; 71 72 srx.srx_service = YFS_CM_SERVICE; 73 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 74 if (ret < 0) 75 goto error_2; 76 77 /* Ideally, we'd turn on service upgrade here, but we can't because 78 * OpenAFS is buggy and leaks the userStatus field from packet to 79 * packet and between FS packets and CB packets - so if we try to do an 80 * upgrade on an FS packet, OpenAFS will leak that into the CB packet 81 * it sends back to us. 82 */ 83 84 rxrpc_kernel_new_call_notification(socket, afs_rx_new_call, 85 afs_rx_discard_new_call); 86 87 ret = kernel_listen(socket, INT_MAX); 88 if (ret < 0) 89 goto error_2; 90 91 net->socket = socket; 92 afs_charge_preallocation(&net->charge_preallocation_work); 93 _leave(" = 0"); 94 return 0; 95 96 error_2: 97 sock_release(socket); 98 error_1: 99 _leave(" = %d", ret); 100 return ret; 101 } 102 103 /* 104 * close the RxRPC socket AFS was using 105 */ 106 void afs_close_socket(struct afs_net *net) 107 { 108 _enter(""); 109 110 kernel_listen(net->socket, 0); 111 flush_workqueue(afs_async_calls); 112 113 if (net->spare_incoming_call) { 114 afs_put_call(net->spare_incoming_call); 115 net->spare_incoming_call = NULL; 116 } 117 118 _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls)); 119 wait_var_event(&net->nr_outstanding_calls, 120 !atomic_read(&net->nr_outstanding_calls)); 121 _debug("no outstanding calls"); 122 123 kernel_sock_shutdown(net->socket, SHUT_RDWR); 124 flush_workqueue(afs_async_calls); 125 sock_release(net->socket); 126 127 _debug("dework"); 128 _leave(""); 129 } 130 131 /* 132 * Allocate a call. 133 */ 134 static struct afs_call *afs_alloc_call(struct afs_net *net, 135 const struct afs_call_type *type, 136 gfp_t gfp) 137 { 138 struct afs_call *call; 139 int o; 140 141 call = kzalloc(sizeof(*call), gfp); 142 if (!call) 143 return NULL; 144 145 call->type = type; 146 call->net = net; 147 call->debug_id = atomic_inc_return(&rxrpc_debug_id); 148 atomic_set(&call->usage, 1); 149 INIT_WORK(&call->async_work, afs_process_async_call); 150 init_waitqueue_head(&call->waitq); 151 spin_lock_init(&call->state_lock); 152 call->iter = &call->def_iter; 153 154 o = atomic_inc_return(&net->nr_outstanding_calls); 155 trace_afs_call(call, afs_call_trace_alloc, 1, o, 156 __builtin_return_address(0)); 157 return call; 158 } 159 160 /* 161 * Dispose of a reference on a call. 162 */ 163 void afs_put_call(struct afs_call *call) 164 { 165 struct afs_net *net = call->net; 166 int n = atomic_dec_return(&call->usage); 167 int o = atomic_read(&net->nr_outstanding_calls); 168 169 trace_afs_call(call, afs_call_trace_put, n, o, 170 __builtin_return_address(0)); 171 172 ASSERTCMP(n, >=, 0); 173 if (n == 0) { 174 ASSERT(!work_pending(&call->async_work)); 175 ASSERT(call->type->name != NULL); 176 177 if (call->rxcall) { 178 rxrpc_kernel_end_call(net->socket, call->rxcall); 179 call->rxcall = NULL; 180 } 181 if (call->type->destructor) 182 call->type->destructor(call); 183 184 afs_put_server(call->net, call->server, afs_server_trace_put_call); 185 afs_put_cb_interest(call->net, call->cbi); 186 afs_put_addrlist(call->alist); 187 kfree(call->request); 188 189 trace_afs_call(call, afs_call_trace_free, 0, o, 190 __builtin_return_address(0)); 191 kfree(call); 192 193 o = atomic_dec_return(&net->nr_outstanding_calls); 194 if (o == 0) 195 wake_up_var(&net->nr_outstanding_calls); 196 } 197 } 198 199 static struct afs_call *afs_get_call(struct afs_call *call, 200 enum afs_call_trace why) 201 { 202 int u = atomic_inc_return(&call->usage); 203 204 trace_afs_call(call, why, u, 205 atomic_read(&call->net->nr_outstanding_calls), 206 __builtin_return_address(0)); 207 return call; 208 } 209 210 /* 211 * Queue the call for actual work. 212 */ 213 static void afs_queue_call_work(struct afs_call *call) 214 { 215 if (call->type->work) { 216 INIT_WORK(&call->work, call->type->work); 217 218 afs_get_call(call, afs_call_trace_work); 219 if (!queue_work(afs_wq, &call->work)) 220 afs_put_call(call); 221 } 222 } 223 224 /* 225 * allocate a call with flat request and reply buffers 226 */ 227 struct afs_call *afs_alloc_flat_call(struct afs_net *net, 228 const struct afs_call_type *type, 229 size_t request_size, size_t reply_max) 230 { 231 struct afs_call *call; 232 233 call = afs_alloc_call(net, type, GFP_NOFS); 234 if (!call) 235 goto nomem_call; 236 237 if (request_size) { 238 call->request_size = request_size; 239 call->request = kmalloc(request_size, GFP_NOFS); 240 if (!call->request) 241 goto nomem_free; 242 } 243 244 if (reply_max) { 245 call->reply_max = reply_max; 246 call->buffer = kmalloc(reply_max, GFP_NOFS); 247 if (!call->buffer) 248 goto nomem_free; 249 } 250 251 afs_extract_to_buf(call, call->reply_max); 252 call->operation_ID = type->op; 253 init_waitqueue_head(&call->waitq); 254 return call; 255 256 nomem_free: 257 afs_put_call(call); 258 nomem_call: 259 return NULL; 260 } 261 262 /* 263 * clean up a call with flat buffer 264 */ 265 void afs_flat_call_destructor(struct afs_call *call) 266 { 267 _enter(""); 268 269 kfree(call->request); 270 call->request = NULL; 271 kfree(call->buffer); 272 call->buffer = NULL; 273 } 274 275 #define AFS_BVEC_MAX 8 276 277 /* 278 * Load the given bvec with the next few pages. 279 */ 280 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg, 281 struct bio_vec *bv, pgoff_t first, pgoff_t last, 282 unsigned offset) 283 { 284 struct page *pages[AFS_BVEC_MAX]; 285 unsigned int nr, n, i, to, bytes = 0; 286 287 nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX); 288 n = find_get_pages_contig(call->mapping, first, nr, pages); 289 ASSERTCMP(n, ==, nr); 290 291 msg->msg_flags |= MSG_MORE; 292 for (i = 0; i < nr; i++) { 293 to = PAGE_SIZE; 294 if (first + i >= last) { 295 to = call->last_to; 296 msg->msg_flags &= ~MSG_MORE; 297 } 298 bv[i].bv_page = pages[i]; 299 bv[i].bv_len = to - offset; 300 bv[i].bv_offset = offset; 301 bytes += to - offset; 302 offset = 0; 303 } 304 305 iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes); 306 } 307 308 /* 309 * Advance the AFS call state when the RxRPC call ends the transmit phase. 310 */ 311 static void afs_notify_end_request_tx(struct sock *sock, 312 struct rxrpc_call *rxcall, 313 unsigned long call_user_ID) 314 { 315 struct afs_call *call = (struct afs_call *)call_user_ID; 316 317 afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY); 318 } 319 320 /* 321 * attach the data from a bunch of pages on an inode to a call 322 */ 323 static int afs_send_pages(struct afs_call *call, struct msghdr *msg) 324 { 325 struct bio_vec bv[AFS_BVEC_MAX]; 326 unsigned int bytes, nr, loop, offset; 327 pgoff_t first = call->first, last = call->last; 328 int ret; 329 330 offset = call->first_offset; 331 call->first_offset = 0; 332 333 do { 334 afs_load_bvec(call, msg, bv, first, last, offset); 335 trace_afs_send_pages(call, msg, first, last, offset); 336 337 offset = 0; 338 bytes = msg->msg_iter.count; 339 nr = msg->msg_iter.nr_segs; 340 341 ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg, 342 bytes, afs_notify_end_request_tx); 343 for (loop = 0; loop < nr; loop++) 344 put_page(bv[loop].bv_page); 345 if (ret < 0) 346 break; 347 348 first += nr; 349 } while (first <= last); 350 351 trace_afs_sent_pages(call, call->first, last, first, ret); 352 return ret; 353 } 354 355 /* 356 * Initiate a call and synchronously queue up the parameters for dispatch. Any 357 * error is stored into the call struct, which the caller must check for. 358 */ 359 void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) 360 { 361 struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index]; 362 struct rxrpc_call *rxcall; 363 struct msghdr msg; 364 struct kvec iov[1]; 365 s64 tx_total_len; 366 int ret; 367 368 _enter(",{%pISp},", &srx->transport); 369 370 ASSERT(call->type != NULL); 371 ASSERT(call->type->name != NULL); 372 373 _debug("____MAKE %p{%s,%x} [%d]____", 374 call, call->type->name, key_serial(call->key), 375 atomic_read(&call->net->nr_outstanding_calls)); 376 377 call->addr_ix = ac->index; 378 call->alist = afs_get_addrlist(ac->alist); 379 380 /* Work out the length we're going to transmit. This is awkward for 381 * calls such as FS.StoreData where there's an extra injection of data 382 * after the initial fixed part. 383 */ 384 tx_total_len = call->request_size; 385 if (call->send_pages) { 386 if (call->last == call->first) { 387 tx_total_len += call->last_to - call->first_offset; 388 } else { 389 /* It looks mathematically like you should be able to 390 * combine the following lines with the ones above, but 391 * unsigned arithmetic is fun when it wraps... 392 */ 393 tx_total_len += PAGE_SIZE - call->first_offset; 394 tx_total_len += call->last_to; 395 tx_total_len += (call->last - call->first - 1) * PAGE_SIZE; 396 } 397 } 398 399 /* If the call is going to be asynchronous, we need an extra ref for 400 * the call to hold itself so the caller need not hang on to its ref. 401 */ 402 if (call->async) { 403 afs_get_call(call, afs_call_trace_get); 404 call->drop_ref = true; 405 } 406 407 /* create a call */ 408 rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key, 409 (unsigned long)call, 410 tx_total_len, gfp, 411 (call->async ? 412 afs_wake_up_async_call : 413 afs_wake_up_call_waiter), 414 call->upgrade, 415 (call->intr ? RXRPC_PREINTERRUPTIBLE : 416 RXRPC_UNINTERRUPTIBLE), 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->def_iter, READ, NULL, 0, 0); 517 ret = rxrpc_kernel_recv_data(call->net->socket, 518 call->rxcall, &call->def_iter, 519 false, &remote_abort, 520 &call->service_id); 521 trace_afs_receive_data(call, &call->def_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 out: 588 _leave(""); 589 return; 590 591 local_abort: 592 abort_code = 0; 593 call_complete: 594 afs_set_call_complete(call, ret, remote_abort); 595 state = AFS_CALL_COMPLETE; 596 goto done; 597 } 598 599 /* 600 * Wait synchronously for a call to complete and clean up the call struct. 601 */ 602 long afs_wait_for_call_to_complete(struct afs_call *call, 603 struct afs_addr_cursor *ac) 604 { 605 long ret; 606 bool rxrpc_complete = false; 607 608 DECLARE_WAITQUEUE(myself, current); 609 610 _enter(""); 611 612 ret = call->error; 613 if (ret < 0) 614 goto out; 615 616 add_wait_queue(&call->waitq, &myself); 617 for (;;) { 618 set_current_state(TASK_UNINTERRUPTIBLE); 619 620 /* deliver any messages that are in the queue */ 621 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) && 622 call->need_attention) { 623 call->need_attention = false; 624 __set_current_state(TASK_RUNNING); 625 afs_deliver_to_call(call); 626 continue; 627 } 628 629 if (afs_check_call_state(call, AFS_CALL_COMPLETE)) 630 break; 631 632 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall)) { 633 /* rxrpc terminated the call. */ 634 rxrpc_complete = true; 635 break; 636 } 637 638 schedule(); 639 } 640 641 remove_wait_queue(&call->waitq, &myself); 642 __set_current_state(TASK_RUNNING); 643 644 if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) { 645 if (rxrpc_complete) { 646 afs_set_call_complete(call, call->error, call->abort_code); 647 } else { 648 /* Kill off the call if it's still live. */ 649 _debug("call interrupted"); 650 if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 651 RX_USER_ABORT, -EINTR, "KWI")) 652 afs_set_call_complete(call, -EINTR, 0); 653 } 654 } 655 656 spin_lock_bh(&call->state_lock); 657 ac->abort_code = call->abort_code; 658 ac->error = call->error; 659 spin_unlock_bh(&call->state_lock); 660 661 ret = ac->error; 662 switch (ret) { 663 case 0: 664 ret = call->ret0; 665 call->ret0 = 0; 666 667 /* Fall through */ 668 case -ECONNABORTED: 669 ac->responded = true; 670 break; 671 } 672 673 out: 674 _debug("call complete"); 675 afs_put_call(call); 676 _leave(" = %p", (void *)ret); 677 return ret; 678 } 679 680 /* 681 * wake up a waiting call 682 */ 683 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, 684 unsigned long call_user_ID) 685 { 686 struct afs_call *call = (struct afs_call *)call_user_ID; 687 688 call->need_attention = true; 689 wake_up(&call->waitq); 690 } 691 692 /* 693 * wake up an asynchronous call 694 */ 695 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, 696 unsigned long call_user_ID) 697 { 698 struct afs_call *call = (struct afs_call *)call_user_ID; 699 int u; 700 701 trace_afs_notify_call(rxcall, call); 702 call->need_attention = true; 703 704 u = atomic_fetch_add_unless(&call->usage, 1, 0); 705 if (u != 0) { 706 trace_afs_call(call, afs_call_trace_wake, u + 1, 707 atomic_read(&call->net->nr_outstanding_calls), 708 __builtin_return_address(0)); 709 710 if (!queue_work(afs_async_calls, &call->async_work)) 711 afs_put_call(call); 712 } 713 } 714 715 /* 716 * Perform I/O processing on an asynchronous call. The work item carries a ref 717 * to the call struct that we either need to release or to pass on. 718 */ 719 static void afs_process_async_call(struct work_struct *work) 720 { 721 struct afs_call *call = container_of(work, struct afs_call, async_work); 722 723 _enter(""); 724 725 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 726 call->need_attention = false; 727 afs_deliver_to_call(call); 728 } 729 730 afs_put_call(call); 731 _leave(""); 732 } 733 734 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) 735 { 736 struct afs_call *call = (struct afs_call *)user_call_ID; 737 738 call->rxcall = rxcall; 739 } 740 741 /* 742 * Charge the incoming call preallocation. 743 */ 744 void afs_charge_preallocation(struct work_struct *work) 745 { 746 struct afs_net *net = 747 container_of(work, struct afs_net, charge_preallocation_work); 748 struct afs_call *call = net->spare_incoming_call; 749 750 for (;;) { 751 if (!call) { 752 call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL); 753 if (!call) 754 break; 755 756 call->drop_ref = true; 757 call->async = true; 758 call->state = AFS_CALL_SV_AWAIT_OP_ID; 759 init_waitqueue_head(&call->waitq); 760 afs_extract_to_tmp(call); 761 } 762 763 if (rxrpc_kernel_charge_accept(net->socket, 764 afs_wake_up_async_call, 765 afs_rx_attach, 766 (unsigned long)call, 767 GFP_KERNEL, 768 call->debug_id) < 0) 769 break; 770 call = NULL; 771 } 772 net->spare_incoming_call = call; 773 } 774 775 /* 776 * Discard a preallocated call when a socket is shut down. 777 */ 778 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, 779 unsigned long user_call_ID) 780 { 781 struct afs_call *call = (struct afs_call *)user_call_ID; 782 783 call->rxcall = NULL; 784 afs_put_call(call); 785 } 786 787 /* 788 * Notification of an incoming call. 789 */ 790 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, 791 unsigned long user_call_ID) 792 { 793 struct afs_net *net = afs_sock2net(sk); 794 795 queue_work(afs_wq, &net->charge_preallocation_work); 796 } 797 798 /* 799 * Grab the operation ID from an incoming cache manager call. The socket 800 * buffer is discarded on error or if we don't yet have sufficient data. 801 */ 802 static int afs_deliver_cm_op_id(struct afs_call *call) 803 { 804 int ret; 805 806 _enter("{%zu}", iov_iter_count(call->iter)); 807 808 /* the operation ID forms the first four bytes of the request data */ 809 ret = afs_extract_data(call, true); 810 if (ret < 0) 811 return ret; 812 813 call->operation_ID = ntohl(call->tmp); 814 afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST); 815 816 /* ask the cache manager to route the call (it'll change the call type 817 * if successful) */ 818 if (!afs_cm_incoming_call(call)) 819 return -ENOTSUPP; 820 821 trace_afs_cb_call(call); 822 823 /* pass responsibility for the remainer of this message off to the 824 * cache manager op */ 825 return call->type->deliver(call); 826 } 827 828 /* 829 * Advance the AFS call state when an RxRPC service call ends the transmit 830 * phase. 831 */ 832 static void afs_notify_end_reply_tx(struct sock *sock, 833 struct rxrpc_call *rxcall, 834 unsigned long call_user_ID) 835 { 836 struct afs_call *call = (struct afs_call *)call_user_ID; 837 838 afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK); 839 } 840 841 /* 842 * send an empty reply 843 */ 844 void afs_send_empty_reply(struct afs_call *call) 845 { 846 struct afs_net *net = call->net; 847 struct msghdr msg; 848 849 _enter(""); 850 851 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0); 852 853 msg.msg_name = NULL; 854 msg.msg_namelen = 0; 855 iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0); 856 msg.msg_control = NULL; 857 msg.msg_controllen = 0; 858 msg.msg_flags = 0; 859 860 switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0, 861 afs_notify_end_reply_tx)) { 862 case 0: 863 _leave(" [replied]"); 864 return; 865 866 case -ENOMEM: 867 _debug("oom"); 868 rxrpc_kernel_abort_call(net->socket, call->rxcall, 869 RX_USER_ABORT, -ENOMEM, "KOO"); 870 /* Fall through */ 871 default: 872 _leave(" [error]"); 873 return; 874 } 875 } 876 877 /* 878 * send a simple reply 879 */ 880 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 881 { 882 struct afs_net *net = call->net; 883 struct msghdr msg; 884 struct kvec iov[1]; 885 int n; 886 887 _enter(""); 888 889 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len); 890 891 iov[0].iov_base = (void *) buf; 892 iov[0].iov_len = len; 893 msg.msg_name = NULL; 894 msg.msg_namelen = 0; 895 iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); 896 msg.msg_control = NULL; 897 msg.msg_controllen = 0; 898 msg.msg_flags = 0; 899 900 n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len, 901 afs_notify_end_reply_tx); 902 if (n >= 0) { 903 /* Success */ 904 _leave(" [replied]"); 905 return; 906 } 907 908 if (n == -ENOMEM) { 909 _debug("oom"); 910 rxrpc_kernel_abort_call(net->socket, call->rxcall, 911 RX_USER_ABORT, -ENOMEM, "KOO"); 912 } 913 _leave(" [error]"); 914 } 915 916 /* 917 * Extract a piece of data from the received data socket buffers. 918 */ 919 int afs_extract_data(struct afs_call *call, bool want_more) 920 { 921 struct afs_net *net = call->net; 922 struct iov_iter *iter = call->iter; 923 enum afs_call_state state; 924 u32 remote_abort = 0; 925 int ret; 926 927 _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more); 928 929 ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter, 930 want_more, &remote_abort, 931 &call->service_id); 932 if (ret == 0 || ret == -EAGAIN) 933 return ret; 934 935 state = READ_ONCE(call->state); 936 if (ret == 1) { 937 switch (state) { 938 case AFS_CALL_CL_AWAIT_REPLY: 939 afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY); 940 break; 941 case AFS_CALL_SV_AWAIT_REQUEST: 942 afs_set_call_state(call, state, AFS_CALL_SV_REPLYING); 943 break; 944 case AFS_CALL_COMPLETE: 945 kdebug("prem complete %d", call->error); 946 return afs_io_error(call, afs_io_error_extract); 947 default: 948 break; 949 } 950 return 0; 951 } 952 953 afs_set_call_complete(call, ret, remote_abort); 954 return ret; 955 } 956 957 /* 958 * Log protocol error production. 959 */ 960 noinline int afs_protocol_error(struct afs_call *call, int error, 961 enum afs_eproto_cause cause) 962 { 963 trace_afs_protocol_error(call, error, cause); 964 return error; 965 } 966