1 /* Maintain an RxRPC server socket to do AFS communications through 2 * 3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/slab.h> 13 #include <linux/sched/signal.h> 14 15 #include <net/sock.h> 16 #include <net/af_rxrpc.h> 17 #include "internal.h" 18 #include "afs_cm.h" 19 20 struct socket *afs_socket; /* my RxRPC socket */ 21 static struct workqueue_struct *afs_async_calls; 22 static struct afs_call *afs_spare_incoming_call; 23 atomic_t afs_outstanding_calls; 24 25 static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); 26 static int afs_wait_for_call_to_complete(struct afs_call *); 27 static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); 28 static void afs_process_async_call(struct work_struct *); 29 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long); 30 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long); 31 static int afs_deliver_cm_op_id(struct afs_call *); 32 33 /* asynchronous incoming call initial processing */ 34 static const struct afs_call_type afs_RXCMxxxx = { 35 .name = "CB.xxxx", 36 .deliver = afs_deliver_cm_op_id, 37 .abort_to_error = afs_abort_to_error, 38 }; 39 40 static void afs_charge_preallocation(struct work_struct *); 41 42 static DECLARE_WORK(afs_charge_preallocation_work, afs_charge_preallocation); 43 44 static int afs_wait_atomic_t(atomic_t *p) 45 { 46 schedule(); 47 return 0; 48 } 49 50 /* 51 * open an RxRPC socket and bind it to be a server for callback notifications 52 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 53 */ 54 int afs_open_socket(void) 55 { 56 struct sockaddr_rxrpc srx; 57 struct socket *socket; 58 int ret; 59 60 _enter(""); 61 62 ret = -ENOMEM; 63 afs_async_calls = alloc_workqueue("kafsd", WQ_MEM_RECLAIM, 0); 64 if (!afs_async_calls) 65 goto error_0; 66 67 ret = sock_create_kern(&init_net, AF_RXRPC, SOCK_DGRAM, PF_INET, &socket); 68 if (ret < 0) 69 goto error_1; 70 71 socket->sk->sk_allocation = GFP_NOFS; 72 73 /* bind the callback manager's address to make this a server socket */ 74 srx.srx_family = AF_RXRPC; 75 srx.srx_service = CM_SERVICE; 76 srx.transport_type = SOCK_DGRAM; 77 srx.transport_len = sizeof(srx.transport.sin); 78 srx.transport.sin.sin_family = AF_INET; 79 srx.transport.sin.sin_port = htons(AFS_CM_PORT); 80 memset(&srx.transport.sin.sin_addr, 0, 81 sizeof(srx.transport.sin.sin_addr)); 82 83 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 84 if (ret < 0) 85 goto error_2; 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 afs_socket = socket; 95 afs_charge_preallocation(NULL); 96 _leave(" = 0"); 97 return 0; 98 99 error_2: 100 sock_release(socket); 101 error_1: 102 destroy_workqueue(afs_async_calls); 103 error_0: 104 _leave(" = %d", ret); 105 return ret; 106 } 107 108 /* 109 * close the RxRPC socket AFS was using 110 */ 111 void afs_close_socket(void) 112 { 113 _enter(""); 114 115 kernel_listen(afs_socket, 0); 116 flush_workqueue(afs_async_calls); 117 118 if (afs_spare_incoming_call) { 119 afs_put_call(afs_spare_incoming_call); 120 afs_spare_incoming_call = NULL; 121 } 122 123 _debug("outstanding %u", atomic_read(&afs_outstanding_calls)); 124 wait_on_atomic_t(&afs_outstanding_calls, afs_wait_atomic_t, 125 TASK_UNINTERRUPTIBLE); 126 _debug("no outstanding calls"); 127 128 kernel_sock_shutdown(afs_socket, SHUT_RDWR); 129 flush_workqueue(afs_async_calls); 130 sock_release(afs_socket); 131 132 _debug("dework"); 133 destroy_workqueue(afs_async_calls); 134 _leave(""); 135 } 136 137 /* 138 * Allocate a call. 139 */ 140 static struct afs_call *afs_alloc_call(const struct afs_call_type *type, 141 gfp_t gfp) 142 { 143 struct afs_call *call; 144 int o; 145 146 call = kzalloc(sizeof(*call), gfp); 147 if (!call) 148 return NULL; 149 150 call->type = type; 151 atomic_set(&call->usage, 1); 152 INIT_WORK(&call->async_work, afs_process_async_call); 153 init_waitqueue_head(&call->waitq); 154 155 o = atomic_inc_return(&afs_outstanding_calls); 156 trace_afs_call(call, afs_call_trace_alloc, 1, o, 157 __builtin_return_address(0)); 158 return call; 159 } 160 161 /* 162 * Dispose of a reference on a call. 163 */ 164 void afs_put_call(struct afs_call *call) 165 { 166 int n = atomic_dec_return(&call->usage); 167 int o = atomic_read(&afs_outstanding_calls); 168 169 trace_afs_call(call, afs_call_trace_put, n + 1, 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(afs_socket, call->rxcall); 179 call->rxcall = NULL; 180 } 181 if (call->type->destructor) 182 call->type->destructor(call); 183 184 kfree(call->request); 185 kfree(call); 186 187 o = atomic_dec_return(&afs_outstanding_calls); 188 trace_afs_call(call, afs_call_trace_free, 0, o, 189 __builtin_return_address(0)); 190 if (o == 0) 191 wake_up_atomic_t(&afs_outstanding_calls); 192 } 193 } 194 195 /* 196 * Queue the call for actual work. Returns 0 unconditionally for convenience. 197 */ 198 int afs_queue_call_work(struct afs_call *call) 199 { 200 int u = atomic_inc_return(&call->usage); 201 202 trace_afs_call(call, afs_call_trace_work, u, 203 atomic_read(&afs_outstanding_calls), 204 __builtin_return_address(0)); 205 206 INIT_WORK(&call->work, call->type->work); 207 208 if (!queue_work(afs_wq, &call->work)) 209 afs_put_call(call); 210 return 0; 211 } 212 213 /* 214 * allocate a call with flat request and reply buffers 215 */ 216 struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, 217 size_t request_size, size_t reply_max) 218 { 219 struct afs_call *call; 220 221 call = afs_alloc_call(type, GFP_NOFS); 222 if (!call) 223 goto nomem_call; 224 225 if (request_size) { 226 call->request_size = request_size; 227 call->request = kmalloc(request_size, GFP_NOFS); 228 if (!call->request) 229 goto nomem_free; 230 } 231 232 if (reply_max) { 233 call->reply_max = reply_max; 234 call->buffer = kmalloc(reply_max, GFP_NOFS); 235 if (!call->buffer) 236 goto nomem_free; 237 } 238 239 init_waitqueue_head(&call->waitq); 240 return call; 241 242 nomem_free: 243 afs_put_call(call); 244 nomem_call: 245 return NULL; 246 } 247 248 /* 249 * clean up a call with flat buffer 250 */ 251 void afs_flat_call_destructor(struct afs_call *call) 252 { 253 _enter(""); 254 255 kfree(call->request); 256 call->request = NULL; 257 kfree(call->buffer); 258 call->buffer = NULL; 259 } 260 261 #define AFS_BVEC_MAX 8 262 263 /* 264 * Load the given bvec with the next few pages. 265 */ 266 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg, 267 struct bio_vec *bv, pgoff_t first, pgoff_t last, 268 unsigned offset) 269 { 270 struct page *pages[AFS_BVEC_MAX]; 271 unsigned int nr, n, i, to, bytes = 0; 272 273 nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX); 274 n = find_get_pages_contig(call->mapping, first, nr, pages); 275 ASSERTCMP(n, ==, nr); 276 277 msg->msg_flags |= MSG_MORE; 278 for (i = 0; i < nr; i++) { 279 to = PAGE_SIZE; 280 if (first + i >= last) { 281 to = call->last_to; 282 msg->msg_flags &= ~MSG_MORE; 283 } 284 bv[i].bv_page = pages[i]; 285 bv[i].bv_len = to - offset; 286 bv[i].bv_offset = offset; 287 bytes += to - offset; 288 offset = 0; 289 } 290 291 iov_iter_bvec(&msg->msg_iter, WRITE | ITER_BVEC, bv, nr, bytes); 292 } 293 294 /* 295 * Advance the AFS call state when the RxRPC call ends the transmit phase. 296 */ 297 static void afs_notify_end_request_tx(struct sock *sock, 298 struct rxrpc_call *rxcall, 299 unsigned long call_user_ID) 300 { 301 struct afs_call *call = (struct afs_call *)call_user_ID; 302 303 if (call->state == AFS_CALL_REQUESTING) 304 call->state = AFS_CALL_AWAIT_REPLY; 305 } 306 307 /* 308 * attach the data from a bunch of pages on an inode to a call 309 */ 310 static int afs_send_pages(struct afs_call *call, struct msghdr *msg) 311 { 312 struct bio_vec bv[AFS_BVEC_MAX]; 313 unsigned int bytes, nr, loop, offset; 314 pgoff_t first = call->first, last = call->last; 315 int ret; 316 317 offset = call->first_offset; 318 call->first_offset = 0; 319 320 do { 321 afs_load_bvec(call, msg, bv, first, last, offset); 322 offset = 0; 323 bytes = msg->msg_iter.count; 324 nr = msg->msg_iter.nr_segs; 325 326 ret = rxrpc_kernel_send_data(afs_socket, call->rxcall, msg, 327 bytes, afs_notify_end_request_tx); 328 for (loop = 0; loop < nr; loop++) 329 put_page(bv[loop].bv_page); 330 if (ret < 0) 331 break; 332 333 first += nr; 334 } while (first <= last); 335 336 return ret; 337 } 338 339 /* 340 * initiate a call 341 */ 342 int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, 343 bool async) 344 { 345 struct sockaddr_rxrpc srx; 346 struct rxrpc_call *rxcall; 347 struct msghdr msg; 348 struct kvec iov[1]; 349 size_t offset; 350 s64 tx_total_len; 351 u32 abort_code; 352 int ret; 353 354 _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); 355 356 ASSERT(call->type != NULL); 357 ASSERT(call->type->name != NULL); 358 359 _debug("____MAKE %p{%s,%x} [%d]____", 360 call, call->type->name, key_serial(call->key), 361 atomic_read(&afs_outstanding_calls)); 362 363 call->async = async; 364 365 memset(&srx, 0, sizeof(srx)); 366 srx.srx_family = AF_RXRPC; 367 srx.srx_service = call->service_id; 368 srx.transport_type = SOCK_DGRAM; 369 srx.transport_len = sizeof(srx.transport.sin); 370 srx.transport.sin.sin_family = AF_INET; 371 srx.transport.sin.sin_port = call->port; 372 memcpy(&srx.transport.sin.sin_addr, addr, 4); 373 374 /* Work out the length we're going to transmit. This is awkward for 375 * calls such as FS.StoreData where there's an extra injection of data 376 * after the initial fixed part. 377 */ 378 tx_total_len = call->request_size; 379 if (call->send_pages) { 380 tx_total_len += call->last_to - call->first_offset; 381 tx_total_len += (call->last - call->first) * PAGE_SIZE; 382 } 383 384 /* create a call */ 385 rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key, 386 (unsigned long)call, 387 tx_total_len, gfp, 388 (async ? 389 afs_wake_up_async_call : 390 afs_wake_up_call_waiter), 391 call->upgrade); 392 call->key = NULL; 393 if (IS_ERR(rxcall)) { 394 ret = PTR_ERR(rxcall); 395 goto error_kill_call; 396 } 397 398 call->rxcall = rxcall; 399 400 /* send the request */ 401 iov[0].iov_base = call->request; 402 iov[0].iov_len = call->request_size; 403 404 msg.msg_name = NULL; 405 msg.msg_namelen = 0; 406 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, 407 call->request_size); 408 msg.msg_control = NULL; 409 msg.msg_controllen = 0; 410 msg.msg_flags = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0); 411 412 /* We have to change the state *before* sending the last packet as 413 * rxrpc might give us the reply before it returns from sending the 414 * request. Further, if the send fails, we may already have been given 415 * a notification and may have collected it. 416 */ 417 if (!call->send_pages) 418 call->state = AFS_CALL_AWAIT_REPLY; 419 ret = rxrpc_kernel_send_data(afs_socket, rxcall, 420 &msg, call->request_size, 421 afs_notify_end_request_tx); 422 if (ret < 0) 423 goto error_do_abort; 424 425 if (call->send_pages) { 426 ret = afs_send_pages(call, &msg); 427 if (ret < 0) 428 goto error_do_abort; 429 } 430 431 /* at this point, an async call may no longer exist as it may have 432 * already completed */ 433 if (call->async) 434 return -EINPROGRESS; 435 436 return afs_wait_for_call_to_complete(call); 437 438 error_do_abort: 439 call->state = AFS_CALL_COMPLETE; 440 if (ret != -ECONNABORTED) { 441 rxrpc_kernel_abort_call(afs_socket, rxcall, RX_USER_ABORT, 442 ret, "KSD"); 443 } else { 444 abort_code = 0; 445 offset = 0; 446 rxrpc_kernel_recv_data(afs_socket, rxcall, NULL, 0, &offset, 447 false, &abort_code, &call->service_id); 448 ret = call->type->abort_to_error(abort_code); 449 } 450 error_kill_call: 451 afs_put_call(call); 452 _leave(" = %d", ret); 453 return ret; 454 } 455 456 /* 457 * deliver messages to a call 458 */ 459 static void afs_deliver_to_call(struct afs_call *call) 460 { 461 u32 abort_code; 462 int ret; 463 464 _enter("%s", call->type->name); 465 466 while (call->state == AFS_CALL_AWAIT_REPLY || 467 call->state == AFS_CALL_AWAIT_OP_ID || 468 call->state == AFS_CALL_AWAIT_REQUEST || 469 call->state == AFS_CALL_AWAIT_ACK 470 ) { 471 if (call->state == AFS_CALL_AWAIT_ACK) { 472 size_t offset = 0; 473 ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, 474 NULL, 0, &offset, false, 475 &call->abort_code, 476 &call->service_id); 477 trace_afs_recv_data(call, 0, offset, false, ret); 478 479 if (ret == -EINPROGRESS || ret == -EAGAIN) 480 return; 481 if (ret == 1 || ret < 0) { 482 call->state = AFS_CALL_COMPLETE; 483 goto done; 484 } 485 return; 486 } 487 488 ret = call->type->deliver(call); 489 switch (ret) { 490 case 0: 491 if (call->state == AFS_CALL_AWAIT_REPLY) 492 call->state = AFS_CALL_COMPLETE; 493 goto done; 494 case -EINPROGRESS: 495 case -EAGAIN: 496 goto out; 497 case -ECONNABORTED: 498 goto call_complete; 499 case -ENOTCONN: 500 abort_code = RX_CALL_DEAD; 501 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 502 abort_code, ret, "KNC"); 503 goto save_error; 504 case -ENOTSUPP: 505 abort_code = RXGEN_OPCODE; 506 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 507 abort_code, ret, "KIV"); 508 goto save_error; 509 case -ENODATA: 510 case -EBADMSG: 511 case -EMSGSIZE: 512 default: 513 abort_code = RXGEN_CC_UNMARSHAL; 514 if (call->state != AFS_CALL_AWAIT_REPLY) 515 abort_code = RXGEN_SS_UNMARSHAL; 516 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 517 abort_code, -EBADMSG, "KUM"); 518 goto save_error; 519 } 520 } 521 522 done: 523 if (call->state == AFS_CALL_COMPLETE && call->incoming) 524 afs_put_call(call); 525 out: 526 _leave(""); 527 return; 528 529 save_error: 530 call->error = ret; 531 call_complete: 532 call->state = AFS_CALL_COMPLETE; 533 goto done; 534 } 535 536 /* 537 * wait synchronously for a call to complete 538 */ 539 static int afs_wait_for_call_to_complete(struct afs_call *call) 540 { 541 signed long rtt2, timeout; 542 int ret; 543 u64 rtt; 544 u32 life, last_life; 545 546 DECLARE_WAITQUEUE(myself, current); 547 548 _enter(""); 549 550 rtt = rxrpc_kernel_get_rtt(afs_socket, call->rxcall); 551 rtt2 = nsecs_to_jiffies64(rtt) * 2; 552 if (rtt2 < 2) 553 rtt2 = 2; 554 555 timeout = rtt2; 556 last_life = rxrpc_kernel_check_life(afs_socket, call->rxcall); 557 558 add_wait_queue(&call->waitq, &myself); 559 for (;;) { 560 set_current_state(TASK_UNINTERRUPTIBLE); 561 562 /* deliver any messages that are in the queue */ 563 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 564 call->need_attention = false; 565 __set_current_state(TASK_RUNNING); 566 afs_deliver_to_call(call); 567 continue; 568 } 569 570 if (call->state == AFS_CALL_COMPLETE) 571 break; 572 573 life = rxrpc_kernel_check_life(afs_socket, call->rxcall); 574 if (timeout == 0 && 575 life == last_life && signal_pending(current)) 576 break; 577 578 if (life != last_life) { 579 timeout = rtt2; 580 last_life = life; 581 } 582 583 timeout = schedule_timeout(timeout); 584 } 585 586 remove_wait_queue(&call->waitq, &myself); 587 __set_current_state(TASK_RUNNING); 588 589 /* Kill off the call if it's still live. */ 590 if (call->state < AFS_CALL_COMPLETE) { 591 _debug("call interrupted"); 592 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 593 RX_USER_ABORT, -EINTR, "KWI"); 594 } 595 596 ret = call->error; 597 _debug("call complete"); 598 afs_put_call(call); 599 _leave(" = %d", ret); 600 return ret; 601 } 602 603 /* 604 * wake up a waiting call 605 */ 606 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, 607 unsigned long call_user_ID) 608 { 609 struct afs_call *call = (struct afs_call *)call_user_ID; 610 611 call->need_attention = true; 612 wake_up(&call->waitq); 613 } 614 615 /* 616 * wake up an asynchronous call 617 */ 618 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, 619 unsigned long call_user_ID) 620 { 621 struct afs_call *call = (struct afs_call *)call_user_ID; 622 int u; 623 624 trace_afs_notify_call(rxcall, call); 625 call->need_attention = true; 626 627 u = __atomic_add_unless(&call->usage, 1, 0); 628 if (u != 0) { 629 trace_afs_call(call, afs_call_trace_wake, u, 630 atomic_read(&afs_outstanding_calls), 631 __builtin_return_address(0)); 632 633 if (!queue_work(afs_async_calls, &call->async_work)) 634 afs_put_call(call); 635 } 636 } 637 638 /* 639 * Delete an asynchronous call. The work item carries a ref to the call struct 640 * that we need to release. 641 */ 642 static void afs_delete_async_call(struct work_struct *work) 643 { 644 struct afs_call *call = container_of(work, struct afs_call, async_work); 645 646 _enter(""); 647 648 afs_put_call(call); 649 650 _leave(""); 651 } 652 653 /* 654 * Perform I/O processing on an asynchronous call. The work item carries a ref 655 * to the call struct that we either need to release or to pass on. 656 */ 657 static void afs_process_async_call(struct work_struct *work) 658 { 659 struct afs_call *call = container_of(work, struct afs_call, async_work); 660 661 _enter(""); 662 663 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 664 call->need_attention = false; 665 afs_deliver_to_call(call); 666 } 667 668 if (call->state == AFS_CALL_COMPLETE) { 669 call->reply = NULL; 670 671 /* We have two refs to release - one from the alloc and one 672 * queued with the work item - and we can't just deallocate the 673 * call because the work item may be queued again. 674 */ 675 call->async_work.func = afs_delete_async_call; 676 if (!queue_work(afs_async_calls, &call->async_work)) 677 afs_put_call(call); 678 } 679 680 afs_put_call(call); 681 _leave(""); 682 } 683 684 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) 685 { 686 struct afs_call *call = (struct afs_call *)user_call_ID; 687 688 call->rxcall = rxcall; 689 } 690 691 /* 692 * Charge the incoming call preallocation. 693 */ 694 static void afs_charge_preallocation(struct work_struct *work) 695 { 696 struct afs_call *call = afs_spare_incoming_call; 697 698 for (;;) { 699 if (!call) { 700 call = afs_alloc_call(&afs_RXCMxxxx, GFP_KERNEL); 701 if (!call) 702 break; 703 704 call->async = true; 705 call->state = AFS_CALL_AWAIT_OP_ID; 706 init_waitqueue_head(&call->waitq); 707 } 708 709 if (rxrpc_kernel_charge_accept(afs_socket, 710 afs_wake_up_async_call, 711 afs_rx_attach, 712 (unsigned long)call, 713 GFP_KERNEL) < 0) 714 break; 715 call = NULL; 716 } 717 afs_spare_incoming_call = call; 718 } 719 720 /* 721 * Discard a preallocated call when a socket is shut down. 722 */ 723 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, 724 unsigned long user_call_ID) 725 { 726 struct afs_call *call = (struct afs_call *)user_call_ID; 727 728 call->rxcall = NULL; 729 afs_put_call(call); 730 } 731 732 /* 733 * Notification of an incoming call. 734 */ 735 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, 736 unsigned long user_call_ID) 737 { 738 queue_work(afs_wq, &afs_charge_preallocation_work); 739 } 740 741 /* 742 * Grab the operation ID from an incoming cache manager call. The socket 743 * buffer is discarded on error or if we don't yet have sufficient data. 744 */ 745 static int afs_deliver_cm_op_id(struct afs_call *call) 746 { 747 int ret; 748 749 _enter("{%zu}", call->offset); 750 751 ASSERTCMP(call->offset, <, 4); 752 753 /* the operation ID forms the first four bytes of the request data */ 754 ret = afs_extract_data(call, &call->tmp, 4, true); 755 if (ret < 0) 756 return ret; 757 758 call->operation_ID = ntohl(call->tmp); 759 call->state = AFS_CALL_AWAIT_REQUEST; 760 call->offset = 0; 761 762 /* ask the cache manager to route the call (it'll change the call type 763 * if successful) */ 764 if (!afs_cm_incoming_call(call)) 765 return -ENOTSUPP; 766 767 trace_afs_cb_call(call); 768 769 /* pass responsibility for the remainer of this message off to the 770 * cache manager op */ 771 return call->type->deliver(call); 772 } 773 774 /* 775 * Advance the AFS call state when an RxRPC service call ends the transmit 776 * phase. 777 */ 778 static void afs_notify_end_reply_tx(struct sock *sock, 779 struct rxrpc_call *rxcall, 780 unsigned long call_user_ID) 781 { 782 struct afs_call *call = (struct afs_call *)call_user_ID; 783 784 if (call->state == AFS_CALL_REPLYING) 785 call->state = AFS_CALL_AWAIT_ACK; 786 } 787 788 /* 789 * send an empty reply 790 */ 791 void afs_send_empty_reply(struct afs_call *call) 792 { 793 struct msghdr msg; 794 795 _enter(""); 796 797 rxrpc_kernel_set_tx_length(afs_socket, call->rxcall, 0); 798 799 msg.msg_name = NULL; 800 msg.msg_namelen = 0; 801 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, NULL, 0, 0); 802 msg.msg_control = NULL; 803 msg.msg_controllen = 0; 804 msg.msg_flags = 0; 805 806 call->state = AFS_CALL_AWAIT_ACK; 807 switch (rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, 0, 808 afs_notify_end_reply_tx)) { 809 case 0: 810 _leave(" [replied]"); 811 return; 812 813 case -ENOMEM: 814 _debug("oom"); 815 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 816 RX_USER_ABORT, -ENOMEM, "KOO"); 817 default: 818 _leave(" [error]"); 819 return; 820 } 821 } 822 823 /* 824 * send a simple reply 825 */ 826 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 827 { 828 struct msghdr msg; 829 struct kvec iov[1]; 830 int n; 831 832 _enter(""); 833 834 rxrpc_kernel_set_tx_length(afs_socket, call->rxcall, len); 835 836 iov[0].iov_base = (void *) buf; 837 iov[0].iov_len = len; 838 msg.msg_name = NULL; 839 msg.msg_namelen = 0; 840 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, len); 841 msg.msg_control = NULL; 842 msg.msg_controllen = 0; 843 msg.msg_flags = 0; 844 845 call->state = AFS_CALL_AWAIT_ACK; 846 n = rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, len, 847 afs_notify_end_reply_tx); 848 if (n >= 0) { 849 /* Success */ 850 _leave(" [replied]"); 851 return; 852 } 853 854 if (n == -ENOMEM) { 855 _debug("oom"); 856 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 857 RX_USER_ABORT, -ENOMEM, "KOO"); 858 } 859 _leave(" [error]"); 860 } 861 862 /* 863 * Extract a piece of data from the received data socket buffers. 864 */ 865 int afs_extract_data(struct afs_call *call, void *buf, size_t count, 866 bool want_more) 867 { 868 int ret; 869 870 _enter("{%s,%zu},,%zu,%d", 871 call->type->name, call->offset, count, want_more); 872 873 ASSERTCMP(call->offset, <=, count); 874 875 ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, 876 buf, count, &call->offset, 877 want_more, &call->abort_code, 878 &call->service_id); 879 trace_afs_recv_data(call, count, call->offset, want_more, ret); 880 if (ret == 0 || ret == -EAGAIN) 881 return ret; 882 883 if (ret == 1) { 884 switch (call->state) { 885 case AFS_CALL_AWAIT_REPLY: 886 call->state = AFS_CALL_COMPLETE; 887 break; 888 case AFS_CALL_AWAIT_REQUEST: 889 call->state = AFS_CALL_REPLYING; 890 break; 891 default: 892 break; 893 } 894 return 0; 895 } 896 897 if (ret == -ECONNABORTED) 898 call->error = call->type->abort_to_error(call->abort_code); 899 else 900 call->error = ret; 901 call->state = AFS_CALL_COMPLETE; 902 return ret; 903 } 904