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->key = NULL; 392 if (IS_ERR(rxcall)) { 393 ret = PTR_ERR(rxcall); 394 goto error_kill_call; 395 } 396 397 call->rxcall = rxcall; 398 399 /* send the request */ 400 iov[0].iov_base = call->request; 401 iov[0].iov_len = call->request_size; 402 403 msg.msg_name = NULL; 404 msg.msg_namelen = 0; 405 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, 406 call->request_size); 407 msg.msg_control = NULL; 408 msg.msg_controllen = 0; 409 msg.msg_flags = (call->send_pages ? MSG_MORE : 0); 410 411 /* We have to change the state *before* sending the last packet as 412 * rxrpc might give us the reply before it returns from sending the 413 * request. Further, if the send fails, we may already have been given 414 * a notification and may have collected it. 415 */ 416 if (!call->send_pages) 417 call->state = AFS_CALL_AWAIT_REPLY; 418 ret = rxrpc_kernel_send_data(afs_socket, rxcall, 419 &msg, call->request_size, 420 afs_notify_end_request_tx); 421 if (ret < 0) 422 goto error_do_abort; 423 424 if (call->send_pages) { 425 ret = afs_send_pages(call, &msg); 426 if (ret < 0) 427 goto error_do_abort; 428 } 429 430 /* at this point, an async call may no longer exist as it may have 431 * already completed */ 432 if (call->async) 433 return -EINPROGRESS; 434 435 return afs_wait_for_call_to_complete(call); 436 437 error_do_abort: 438 call->state = AFS_CALL_COMPLETE; 439 if (ret != -ECONNABORTED) { 440 rxrpc_kernel_abort_call(afs_socket, rxcall, RX_USER_ABORT, 441 ret, "KSD"); 442 } else { 443 abort_code = 0; 444 offset = 0; 445 rxrpc_kernel_recv_data(afs_socket, rxcall, NULL, 0, &offset, 446 false, &abort_code); 447 ret = call->type->abort_to_error(abort_code); 448 } 449 error_kill_call: 450 afs_put_call(call); 451 _leave(" = %d", ret); 452 return ret; 453 } 454 455 /* 456 * deliver messages to a call 457 */ 458 static void afs_deliver_to_call(struct afs_call *call) 459 { 460 u32 abort_code; 461 int ret; 462 463 _enter("%s", call->type->name); 464 465 while (call->state == AFS_CALL_AWAIT_REPLY || 466 call->state == AFS_CALL_AWAIT_OP_ID || 467 call->state == AFS_CALL_AWAIT_REQUEST || 468 call->state == AFS_CALL_AWAIT_ACK 469 ) { 470 if (call->state == AFS_CALL_AWAIT_ACK) { 471 size_t offset = 0; 472 ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, 473 NULL, 0, &offset, false, 474 &call->abort_code); 475 trace_afs_recv_data(call, 0, offset, false, ret); 476 477 if (ret == -EINPROGRESS || ret == -EAGAIN) 478 return; 479 if (ret == 1 || ret < 0) { 480 call->state = AFS_CALL_COMPLETE; 481 goto done; 482 } 483 return; 484 } 485 486 ret = call->type->deliver(call); 487 switch (ret) { 488 case 0: 489 if (call->state == AFS_CALL_AWAIT_REPLY) 490 call->state = AFS_CALL_COMPLETE; 491 goto done; 492 case -EINPROGRESS: 493 case -EAGAIN: 494 goto out; 495 case -ECONNABORTED: 496 goto call_complete; 497 case -ENOTCONN: 498 abort_code = RX_CALL_DEAD; 499 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 500 abort_code, ret, "KNC"); 501 goto save_error; 502 case -ENOTSUPP: 503 abort_code = RXGEN_OPCODE; 504 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 505 abort_code, ret, "KIV"); 506 goto save_error; 507 case -ENODATA: 508 case -EBADMSG: 509 case -EMSGSIZE: 510 default: 511 abort_code = RXGEN_CC_UNMARSHAL; 512 if (call->state != AFS_CALL_AWAIT_REPLY) 513 abort_code = RXGEN_SS_UNMARSHAL; 514 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 515 abort_code, -EBADMSG, "KUM"); 516 goto save_error; 517 } 518 } 519 520 done: 521 if (call->state == AFS_CALL_COMPLETE && call->incoming) 522 afs_put_call(call); 523 out: 524 _leave(""); 525 return; 526 527 save_error: 528 call->error = ret; 529 call_complete: 530 call->state = AFS_CALL_COMPLETE; 531 goto done; 532 } 533 534 /* 535 * wait synchronously for a call to complete 536 */ 537 static int afs_wait_for_call_to_complete(struct afs_call *call) 538 { 539 int ret; 540 541 DECLARE_WAITQUEUE(myself, current); 542 543 _enter(""); 544 545 add_wait_queue(&call->waitq, &myself); 546 for (;;) { 547 set_current_state(TASK_INTERRUPTIBLE); 548 549 /* deliver any messages that are in the queue */ 550 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 551 call->need_attention = false; 552 __set_current_state(TASK_RUNNING); 553 afs_deliver_to_call(call); 554 continue; 555 } 556 557 if (call->state == AFS_CALL_COMPLETE || 558 signal_pending(current)) 559 break; 560 schedule(); 561 } 562 563 remove_wait_queue(&call->waitq, &myself); 564 __set_current_state(TASK_RUNNING); 565 566 /* Kill off the call if it's still live. */ 567 if (call->state < AFS_CALL_COMPLETE) { 568 _debug("call interrupted"); 569 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 570 RX_USER_ABORT, -EINTR, "KWI"); 571 } 572 573 ret = call->error; 574 _debug("call complete"); 575 afs_put_call(call); 576 _leave(" = %d", ret); 577 return ret; 578 } 579 580 /* 581 * wake up a waiting call 582 */ 583 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, 584 unsigned long call_user_ID) 585 { 586 struct afs_call *call = (struct afs_call *)call_user_ID; 587 588 call->need_attention = true; 589 wake_up(&call->waitq); 590 } 591 592 /* 593 * wake up an asynchronous call 594 */ 595 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, 596 unsigned long call_user_ID) 597 { 598 struct afs_call *call = (struct afs_call *)call_user_ID; 599 int u; 600 601 trace_afs_notify_call(rxcall, call); 602 call->need_attention = true; 603 604 u = __atomic_add_unless(&call->usage, 1, 0); 605 if (u != 0) { 606 trace_afs_call(call, afs_call_trace_wake, u, 607 atomic_read(&afs_outstanding_calls), 608 __builtin_return_address(0)); 609 610 if (!queue_work(afs_async_calls, &call->async_work)) 611 afs_put_call(call); 612 } 613 } 614 615 /* 616 * Delete an asynchronous call. The work item carries a ref to the call struct 617 * that we need to release. 618 */ 619 static void afs_delete_async_call(struct work_struct *work) 620 { 621 struct afs_call *call = container_of(work, struct afs_call, async_work); 622 623 _enter(""); 624 625 afs_put_call(call); 626 627 _leave(""); 628 } 629 630 /* 631 * Perform I/O processing on an asynchronous call. The work item carries a ref 632 * to the call struct that we either need to release or to pass on. 633 */ 634 static void afs_process_async_call(struct work_struct *work) 635 { 636 struct afs_call *call = container_of(work, struct afs_call, async_work); 637 638 _enter(""); 639 640 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 641 call->need_attention = false; 642 afs_deliver_to_call(call); 643 } 644 645 if (call->state == AFS_CALL_COMPLETE) { 646 call->reply = NULL; 647 648 /* We have two refs to release - one from the alloc and one 649 * queued with the work item - and we can't just deallocate the 650 * call because the work item may be queued again. 651 */ 652 call->async_work.func = afs_delete_async_call; 653 if (!queue_work(afs_async_calls, &call->async_work)) 654 afs_put_call(call); 655 } 656 657 afs_put_call(call); 658 _leave(""); 659 } 660 661 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) 662 { 663 struct afs_call *call = (struct afs_call *)user_call_ID; 664 665 call->rxcall = rxcall; 666 } 667 668 /* 669 * Charge the incoming call preallocation. 670 */ 671 static void afs_charge_preallocation(struct work_struct *work) 672 { 673 struct afs_call *call = afs_spare_incoming_call; 674 675 for (;;) { 676 if (!call) { 677 call = afs_alloc_call(&afs_RXCMxxxx, GFP_KERNEL); 678 if (!call) 679 break; 680 681 call->async = true; 682 call->state = AFS_CALL_AWAIT_OP_ID; 683 init_waitqueue_head(&call->waitq); 684 } 685 686 if (rxrpc_kernel_charge_accept(afs_socket, 687 afs_wake_up_async_call, 688 afs_rx_attach, 689 (unsigned long)call, 690 GFP_KERNEL) < 0) 691 break; 692 call = NULL; 693 } 694 afs_spare_incoming_call = call; 695 } 696 697 /* 698 * Discard a preallocated call when a socket is shut down. 699 */ 700 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, 701 unsigned long user_call_ID) 702 { 703 struct afs_call *call = (struct afs_call *)user_call_ID; 704 705 call->rxcall = NULL; 706 afs_put_call(call); 707 } 708 709 /* 710 * Notification of an incoming call. 711 */ 712 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, 713 unsigned long user_call_ID) 714 { 715 queue_work(afs_wq, &afs_charge_preallocation_work); 716 } 717 718 /* 719 * Grab the operation ID from an incoming cache manager call. The socket 720 * buffer is discarded on error or if we don't yet have sufficient data. 721 */ 722 static int afs_deliver_cm_op_id(struct afs_call *call) 723 { 724 int ret; 725 726 _enter("{%zu}", call->offset); 727 728 ASSERTCMP(call->offset, <, 4); 729 730 /* the operation ID forms the first four bytes of the request data */ 731 ret = afs_extract_data(call, &call->tmp, 4, true); 732 if (ret < 0) 733 return ret; 734 735 call->operation_ID = ntohl(call->tmp); 736 call->state = AFS_CALL_AWAIT_REQUEST; 737 call->offset = 0; 738 739 /* ask the cache manager to route the call (it'll change the call type 740 * if successful) */ 741 if (!afs_cm_incoming_call(call)) 742 return -ENOTSUPP; 743 744 trace_afs_cb_call(call); 745 746 /* pass responsibility for the remainer of this message off to the 747 * cache manager op */ 748 return call->type->deliver(call); 749 } 750 751 /* 752 * Advance the AFS call state when an RxRPC service call ends the transmit 753 * phase. 754 */ 755 static void afs_notify_end_reply_tx(struct sock *sock, 756 struct rxrpc_call *rxcall, 757 unsigned long call_user_ID) 758 { 759 struct afs_call *call = (struct afs_call *)call_user_ID; 760 761 if (call->state == AFS_CALL_REPLYING) 762 call->state = AFS_CALL_AWAIT_ACK; 763 } 764 765 /* 766 * send an empty reply 767 */ 768 void afs_send_empty_reply(struct afs_call *call) 769 { 770 struct msghdr msg; 771 772 _enter(""); 773 774 rxrpc_kernel_set_tx_length(afs_socket, call->rxcall, 0); 775 776 msg.msg_name = NULL; 777 msg.msg_namelen = 0; 778 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, NULL, 0, 0); 779 msg.msg_control = NULL; 780 msg.msg_controllen = 0; 781 msg.msg_flags = 0; 782 783 call->state = AFS_CALL_AWAIT_ACK; 784 switch (rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, 0, 785 afs_notify_end_reply_tx)) { 786 case 0: 787 _leave(" [replied]"); 788 return; 789 790 case -ENOMEM: 791 _debug("oom"); 792 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 793 RX_USER_ABORT, -ENOMEM, "KOO"); 794 default: 795 _leave(" [error]"); 796 return; 797 } 798 } 799 800 /* 801 * send a simple reply 802 */ 803 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 804 { 805 struct msghdr msg; 806 struct kvec iov[1]; 807 int n; 808 809 _enter(""); 810 811 rxrpc_kernel_set_tx_length(afs_socket, call->rxcall, len); 812 813 iov[0].iov_base = (void *) buf; 814 iov[0].iov_len = len; 815 msg.msg_name = NULL; 816 msg.msg_namelen = 0; 817 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, len); 818 msg.msg_control = NULL; 819 msg.msg_controllen = 0; 820 msg.msg_flags = 0; 821 822 call->state = AFS_CALL_AWAIT_ACK; 823 n = rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, len, 824 afs_notify_end_reply_tx); 825 if (n >= 0) { 826 /* Success */ 827 _leave(" [replied]"); 828 return; 829 } 830 831 if (n == -ENOMEM) { 832 _debug("oom"); 833 rxrpc_kernel_abort_call(afs_socket, call->rxcall, 834 RX_USER_ABORT, -ENOMEM, "KOO"); 835 } 836 _leave(" [error]"); 837 } 838 839 /* 840 * Extract a piece of data from the received data socket buffers. 841 */ 842 int afs_extract_data(struct afs_call *call, void *buf, size_t count, 843 bool want_more) 844 { 845 int ret; 846 847 _enter("{%s,%zu},,%zu,%d", 848 call->type->name, call->offset, count, want_more); 849 850 ASSERTCMP(call->offset, <=, count); 851 852 ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, 853 buf, count, &call->offset, 854 want_more, &call->abort_code); 855 trace_afs_recv_data(call, count, call->offset, want_more, ret); 856 if (ret == 0 || ret == -EAGAIN) 857 return ret; 858 859 if (ret == 1) { 860 switch (call->state) { 861 case AFS_CALL_AWAIT_REPLY: 862 call->state = AFS_CALL_COMPLETE; 863 break; 864 case AFS_CALL_AWAIT_REQUEST: 865 call->state = AFS_CALL_REPLYING; 866 break; 867 default: 868 break; 869 } 870 return 0; 871 } 872 873 if (ret == -ECONNABORTED) 874 call->error = call->type->abort_to_error(call->abort_code); 875 else 876 call->error = ret; 877 call->state = AFS_CALL_COMPLETE; 878 return ret; 879 } 880