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 <net/sock.h> 13 #include <net/af_rxrpc.h> 14 #include <rxrpc/packet.h> 15 #include "internal.h" 16 #include "afs_cm.h" 17 18 static struct socket *afs_socket; /* my RxRPC socket */ 19 static struct workqueue_struct *afs_async_calls; 20 static atomic_t afs_outstanding_calls; 21 static atomic_t afs_outstanding_skbs; 22 23 static void afs_wake_up_call_waiter(struct afs_call *); 24 static int afs_wait_for_call_to_complete(struct afs_call *); 25 static void afs_wake_up_async_call(struct afs_call *); 26 static int afs_dont_wait_for_call_to_complete(struct afs_call *); 27 static void afs_process_async_call(struct work_struct *); 28 static void afs_rx_interceptor(struct sock *, unsigned long, struct sk_buff *); 29 static int afs_deliver_cm_op_id(struct afs_call *, struct sk_buff *, bool); 30 31 /* synchronous call management */ 32 const struct afs_wait_mode afs_sync_call = { 33 .rx_wakeup = afs_wake_up_call_waiter, 34 .wait = afs_wait_for_call_to_complete, 35 }; 36 37 /* asynchronous call management */ 38 const struct afs_wait_mode afs_async_call = { 39 .rx_wakeup = afs_wake_up_async_call, 40 .wait = afs_dont_wait_for_call_to_complete, 41 }; 42 43 /* asynchronous incoming call management */ 44 static const struct afs_wait_mode afs_async_incoming_call = { 45 .rx_wakeup = afs_wake_up_async_call, 46 }; 47 48 /* asynchronous incoming call initial processing */ 49 static const struct afs_call_type afs_RXCMxxxx = { 50 .name = "CB.xxxx", 51 .deliver = afs_deliver_cm_op_id, 52 .abort_to_error = afs_abort_to_error, 53 }; 54 55 static void afs_collect_incoming_call(struct work_struct *); 56 57 static struct sk_buff_head afs_incoming_calls; 58 static DECLARE_WORK(afs_collect_incoming_call_work, afs_collect_incoming_call); 59 60 /* 61 * open an RxRPC socket and bind it to be a server for callback notifications 62 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 63 */ 64 int afs_open_socket(void) 65 { 66 struct sockaddr_rxrpc srx; 67 struct socket *socket; 68 int ret; 69 70 _enter(""); 71 72 skb_queue_head_init(&afs_incoming_calls); 73 74 afs_async_calls = create_singlethread_workqueue("kafsd"); 75 if (!afs_async_calls) { 76 _leave(" = -ENOMEM [wq]"); 77 return -ENOMEM; 78 } 79 80 ret = sock_create_kern(AF_RXRPC, SOCK_DGRAM, PF_INET, &socket); 81 if (ret < 0) { 82 destroy_workqueue(afs_async_calls); 83 _leave(" = %d [socket]", ret); 84 return ret; 85 } 86 87 socket->sk->sk_allocation = GFP_NOFS; 88 89 /* bind the callback manager's address to make this a server socket */ 90 srx.srx_family = AF_RXRPC; 91 srx.srx_service = CM_SERVICE; 92 srx.transport_type = SOCK_DGRAM; 93 srx.transport_len = sizeof(srx.transport.sin); 94 srx.transport.sin.sin_family = AF_INET; 95 srx.transport.sin.sin_port = htons(AFS_CM_PORT); 96 memset(&srx.transport.sin.sin_addr, 0, 97 sizeof(srx.transport.sin.sin_addr)); 98 99 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 100 if (ret < 0) { 101 sock_release(socket); 102 _leave(" = %d [bind]", ret); 103 return ret; 104 } 105 106 rxrpc_kernel_intercept_rx_messages(socket, afs_rx_interceptor); 107 108 afs_socket = socket; 109 _leave(" = 0"); 110 return 0; 111 } 112 113 /* 114 * close the RxRPC socket AFS was using 115 */ 116 void afs_close_socket(void) 117 { 118 _enter(""); 119 120 sock_release(afs_socket); 121 122 _debug("dework"); 123 destroy_workqueue(afs_async_calls); 124 125 ASSERTCMP(atomic_read(&afs_outstanding_skbs), ==, 0); 126 ASSERTCMP(atomic_read(&afs_outstanding_calls), ==, 0); 127 _leave(""); 128 } 129 130 /* 131 * note that the data in a socket buffer is now delivered and that the buffer 132 * should be freed 133 */ 134 static void afs_data_delivered(struct sk_buff *skb) 135 { 136 if (!skb) { 137 _debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs)); 138 dump_stack(); 139 } else { 140 _debug("DLVR %p{%u} [%d]", 141 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 142 if (atomic_dec_return(&afs_outstanding_skbs) == -1) 143 BUG(); 144 rxrpc_kernel_data_delivered(skb); 145 } 146 } 147 148 /* 149 * free a socket buffer 150 */ 151 static void afs_free_skb(struct sk_buff *skb) 152 { 153 if (!skb) { 154 _debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs)); 155 dump_stack(); 156 } else { 157 _debug("FREE %p{%u} [%d]", 158 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 159 if (atomic_dec_return(&afs_outstanding_skbs) == -1) 160 BUG(); 161 rxrpc_kernel_free_skb(skb); 162 } 163 } 164 165 /* 166 * free a call 167 */ 168 static void afs_free_call(struct afs_call *call) 169 { 170 _debug("DONE %p{%s} [%d]", 171 call, call->type->name, atomic_read(&afs_outstanding_calls)); 172 if (atomic_dec_return(&afs_outstanding_calls) == -1) 173 BUG(); 174 175 ASSERTCMP(call->rxcall, ==, NULL); 176 ASSERT(!work_pending(&call->async_work)); 177 ASSERT(skb_queue_empty(&call->rx_queue)); 178 ASSERT(call->type->name != NULL); 179 180 kfree(call->request); 181 kfree(call); 182 } 183 184 /* 185 * allocate a call with flat request and reply buffers 186 */ 187 struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, 188 size_t request_size, size_t reply_size) 189 { 190 struct afs_call *call; 191 192 call = kzalloc(sizeof(*call), GFP_NOFS); 193 if (!call) 194 goto nomem_call; 195 196 _debug("CALL %p{%s} [%d]", 197 call, type->name, atomic_read(&afs_outstanding_calls)); 198 atomic_inc(&afs_outstanding_calls); 199 200 call->type = type; 201 call->request_size = request_size; 202 call->reply_max = reply_size; 203 204 if (request_size) { 205 call->request = kmalloc(request_size, GFP_NOFS); 206 if (!call->request) 207 goto nomem_free; 208 } 209 210 if (reply_size) { 211 call->buffer = kmalloc(reply_size, GFP_NOFS); 212 if (!call->buffer) 213 goto nomem_free; 214 } 215 216 init_waitqueue_head(&call->waitq); 217 skb_queue_head_init(&call->rx_queue); 218 return call; 219 220 nomem_free: 221 afs_free_call(call); 222 nomem_call: 223 return NULL; 224 } 225 226 /* 227 * clean up a call with flat buffer 228 */ 229 void afs_flat_call_destructor(struct afs_call *call) 230 { 231 _enter(""); 232 233 kfree(call->request); 234 call->request = NULL; 235 kfree(call->buffer); 236 call->buffer = NULL; 237 } 238 239 /* 240 * attach the data from a bunch of pages on an inode to a call 241 */ 242 static int afs_send_pages(struct afs_call *call, struct msghdr *msg, 243 struct kvec *iov) 244 { 245 struct page *pages[8]; 246 unsigned count, n, loop, offset, to; 247 pgoff_t first = call->first, last = call->last; 248 int ret; 249 250 _enter(""); 251 252 offset = call->first_offset; 253 call->first_offset = 0; 254 255 do { 256 _debug("attach %lx-%lx", first, last); 257 258 count = last - first + 1; 259 if (count > ARRAY_SIZE(pages)) 260 count = ARRAY_SIZE(pages); 261 n = find_get_pages_contig(call->mapping, first, count, pages); 262 ASSERTCMP(n, ==, count); 263 264 loop = 0; 265 do { 266 msg->msg_flags = 0; 267 to = PAGE_SIZE; 268 if (first + loop >= last) 269 to = call->last_to; 270 else 271 msg->msg_flags = MSG_MORE; 272 iov->iov_base = kmap(pages[loop]) + offset; 273 iov->iov_len = to - offset; 274 offset = 0; 275 276 _debug("- range %u-%u%s", 277 offset, to, msg->msg_flags ? " [more]" : ""); 278 msg->msg_iov = (struct iovec *) iov; 279 msg->msg_iovlen = 1; 280 281 /* have to change the state *before* sending the last 282 * packet as RxRPC might give us the reply before it 283 * returns from sending the request */ 284 if (first + loop >= last) 285 call->state = AFS_CALL_AWAIT_REPLY; 286 ret = rxrpc_kernel_send_data(call->rxcall, msg, 287 to - offset); 288 kunmap(pages[loop]); 289 if (ret < 0) 290 break; 291 } while (++loop < count); 292 first += count; 293 294 for (loop = 0; loop < count; loop++) 295 put_page(pages[loop]); 296 if (ret < 0) 297 break; 298 } while (first <= last); 299 300 _leave(" = %d", ret); 301 return ret; 302 } 303 304 /* 305 * initiate a call 306 */ 307 int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, 308 const struct afs_wait_mode *wait_mode) 309 { 310 struct sockaddr_rxrpc srx; 311 struct rxrpc_call *rxcall; 312 struct msghdr msg; 313 struct kvec iov[1]; 314 int ret; 315 316 _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); 317 318 ASSERT(call->type != NULL); 319 ASSERT(call->type->name != NULL); 320 321 _debug("____MAKE %p{%s,%x} [%d]____", 322 call, call->type->name, key_serial(call->key), 323 atomic_read(&afs_outstanding_calls)); 324 325 call->wait_mode = wait_mode; 326 INIT_WORK(&call->async_work, afs_process_async_call); 327 328 memset(&srx, 0, sizeof(srx)); 329 srx.srx_family = AF_RXRPC; 330 srx.srx_service = call->service_id; 331 srx.transport_type = SOCK_DGRAM; 332 srx.transport_len = sizeof(srx.transport.sin); 333 srx.transport.sin.sin_family = AF_INET; 334 srx.transport.sin.sin_port = call->port; 335 memcpy(&srx.transport.sin.sin_addr, addr, 4); 336 337 /* create a call */ 338 rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key, 339 (unsigned long) call, gfp); 340 call->key = NULL; 341 if (IS_ERR(rxcall)) { 342 ret = PTR_ERR(rxcall); 343 goto error_kill_call; 344 } 345 346 call->rxcall = rxcall; 347 348 /* send the request */ 349 iov[0].iov_base = call->request; 350 iov[0].iov_len = call->request_size; 351 352 msg.msg_name = NULL; 353 msg.msg_namelen = 0; 354 msg.msg_iov = (struct iovec *) iov; 355 msg.msg_iovlen = 1; 356 msg.msg_control = NULL; 357 msg.msg_controllen = 0; 358 msg.msg_flags = (call->send_pages ? MSG_MORE : 0); 359 360 /* have to change the state *before* sending the last packet as RxRPC 361 * might give us the reply before it returns from sending the 362 * request */ 363 if (!call->send_pages) 364 call->state = AFS_CALL_AWAIT_REPLY; 365 ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size); 366 if (ret < 0) 367 goto error_do_abort; 368 369 if (call->send_pages) { 370 ret = afs_send_pages(call, &msg, iov); 371 if (ret < 0) 372 goto error_do_abort; 373 } 374 375 /* at this point, an async call may no longer exist as it may have 376 * already completed */ 377 return wait_mode->wait(call); 378 379 error_do_abort: 380 rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT); 381 rxrpc_kernel_end_call(rxcall); 382 call->rxcall = NULL; 383 error_kill_call: 384 call->type->destructor(call); 385 afs_free_call(call); 386 _leave(" = %d", ret); 387 return ret; 388 } 389 390 /* 391 * handles intercepted messages that were arriving in the socket's Rx queue 392 * - called with the socket receive queue lock held to ensure message ordering 393 * - called with softirqs disabled 394 */ 395 static void afs_rx_interceptor(struct sock *sk, unsigned long user_call_ID, 396 struct sk_buff *skb) 397 { 398 struct afs_call *call = (struct afs_call *) user_call_ID; 399 400 _enter("%p,,%u", call, skb->mark); 401 402 _debug("ICPT %p{%u} [%d]", 403 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 404 405 ASSERTCMP(sk, ==, afs_socket->sk); 406 atomic_inc(&afs_outstanding_skbs); 407 408 if (!call) { 409 /* its an incoming call for our callback service */ 410 skb_queue_tail(&afs_incoming_calls, skb); 411 schedule_work(&afs_collect_incoming_call_work); 412 } else { 413 /* route the messages directly to the appropriate call */ 414 skb_queue_tail(&call->rx_queue, skb); 415 call->wait_mode->rx_wakeup(call); 416 } 417 418 _leave(""); 419 } 420 421 /* 422 * deliver messages to a call 423 */ 424 static void afs_deliver_to_call(struct afs_call *call) 425 { 426 struct sk_buff *skb; 427 bool last; 428 u32 abort_code; 429 int ret; 430 431 _enter(""); 432 433 while ((call->state == AFS_CALL_AWAIT_REPLY || 434 call->state == AFS_CALL_AWAIT_OP_ID || 435 call->state == AFS_CALL_AWAIT_REQUEST || 436 call->state == AFS_CALL_AWAIT_ACK) && 437 (skb = skb_dequeue(&call->rx_queue))) { 438 switch (skb->mark) { 439 case RXRPC_SKB_MARK_DATA: 440 _debug("Rcv DATA"); 441 last = rxrpc_kernel_is_data_last(skb); 442 ret = call->type->deliver(call, skb, last); 443 switch (ret) { 444 case 0: 445 if (last && 446 call->state == AFS_CALL_AWAIT_REPLY) 447 call->state = AFS_CALL_COMPLETE; 448 break; 449 case -ENOTCONN: 450 abort_code = RX_CALL_DEAD; 451 goto do_abort; 452 case -ENOTSUPP: 453 abort_code = RX_INVALID_OPERATION; 454 goto do_abort; 455 default: 456 abort_code = RXGEN_CC_UNMARSHAL; 457 if (call->state != AFS_CALL_AWAIT_REPLY) 458 abort_code = RXGEN_SS_UNMARSHAL; 459 do_abort: 460 rxrpc_kernel_abort_call(call->rxcall, 461 abort_code); 462 call->error = ret; 463 call->state = AFS_CALL_ERROR; 464 break; 465 } 466 afs_data_delivered(skb); 467 skb = NULL; 468 continue; 469 case RXRPC_SKB_MARK_FINAL_ACK: 470 _debug("Rcv ACK"); 471 call->state = AFS_CALL_COMPLETE; 472 break; 473 case RXRPC_SKB_MARK_BUSY: 474 _debug("Rcv BUSY"); 475 call->error = -EBUSY; 476 call->state = AFS_CALL_BUSY; 477 break; 478 case RXRPC_SKB_MARK_REMOTE_ABORT: 479 abort_code = rxrpc_kernel_get_abort_code(skb); 480 call->error = call->type->abort_to_error(abort_code); 481 call->state = AFS_CALL_ABORTED; 482 _debug("Rcv ABORT %u -> %d", abort_code, call->error); 483 break; 484 case RXRPC_SKB_MARK_NET_ERROR: 485 call->error = -rxrpc_kernel_get_error_number(skb); 486 call->state = AFS_CALL_ERROR; 487 _debug("Rcv NET ERROR %d", call->error); 488 break; 489 case RXRPC_SKB_MARK_LOCAL_ERROR: 490 call->error = -rxrpc_kernel_get_error_number(skb); 491 call->state = AFS_CALL_ERROR; 492 _debug("Rcv LOCAL ERROR %d", call->error); 493 break; 494 default: 495 BUG(); 496 break; 497 } 498 499 afs_free_skb(skb); 500 } 501 502 /* make sure the queue is empty if the call is done with (we might have 503 * aborted the call early because of an unmarshalling error) */ 504 if (call->state >= AFS_CALL_COMPLETE) { 505 while ((skb = skb_dequeue(&call->rx_queue))) 506 afs_free_skb(skb); 507 if (call->incoming) { 508 rxrpc_kernel_end_call(call->rxcall); 509 call->rxcall = NULL; 510 call->type->destructor(call); 511 afs_free_call(call); 512 } 513 } 514 515 _leave(""); 516 } 517 518 /* 519 * wait synchronously for a call to complete 520 */ 521 static int afs_wait_for_call_to_complete(struct afs_call *call) 522 { 523 struct sk_buff *skb; 524 int ret; 525 526 DECLARE_WAITQUEUE(myself, current); 527 528 _enter(""); 529 530 add_wait_queue(&call->waitq, &myself); 531 for (;;) { 532 set_current_state(TASK_INTERRUPTIBLE); 533 534 /* deliver any messages that are in the queue */ 535 if (!skb_queue_empty(&call->rx_queue)) { 536 __set_current_state(TASK_RUNNING); 537 afs_deliver_to_call(call); 538 continue; 539 } 540 541 ret = call->error; 542 if (call->state >= AFS_CALL_COMPLETE) 543 break; 544 ret = -EINTR; 545 if (signal_pending(current)) 546 break; 547 schedule(); 548 } 549 550 remove_wait_queue(&call->waitq, &myself); 551 __set_current_state(TASK_RUNNING); 552 553 /* kill the call */ 554 if (call->state < AFS_CALL_COMPLETE) { 555 _debug("call incomplete"); 556 rxrpc_kernel_abort_call(call->rxcall, RX_CALL_DEAD); 557 while ((skb = skb_dequeue(&call->rx_queue))) 558 afs_free_skb(skb); 559 } 560 561 _debug("call complete"); 562 rxrpc_kernel_end_call(call->rxcall); 563 call->rxcall = NULL; 564 call->type->destructor(call); 565 afs_free_call(call); 566 _leave(" = %d", ret); 567 return ret; 568 } 569 570 /* 571 * wake up a waiting call 572 */ 573 static void afs_wake_up_call_waiter(struct afs_call *call) 574 { 575 wake_up(&call->waitq); 576 } 577 578 /* 579 * wake up an asynchronous call 580 */ 581 static void afs_wake_up_async_call(struct afs_call *call) 582 { 583 _enter(""); 584 queue_work(afs_async_calls, &call->async_work); 585 } 586 587 /* 588 * put a call into asynchronous mode 589 * - mustn't touch the call descriptor as the call my have completed by the 590 * time we get here 591 */ 592 static int afs_dont_wait_for_call_to_complete(struct afs_call *call) 593 { 594 _enter(""); 595 return -EINPROGRESS; 596 } 597 598 /* 599 * delete an asynchronous call 600 */ 601 static void afs_delete_async_call(struct work_struct *work) 602 { 603 struct afs_call *call = 604 container_of(work, struct afs_call, async_work); 605 606 _enter(""); 607 608 afs_free_call(call); 609 610 _leave(""); 611 } 612 613 /* 614 * perform processing on an asynchronous call 615 * - on a multiple-thread workqueue this work item may try to run on several 616 * CPUs at the same time 617 */ 618 static void afs_process_async_call(struct work_struct *work) 619 { 620 struct afs_call *call = 621 container_of(work, struct afs_call, async_work); 622 623 _enter(""); 624 625 if (!skb_queue_empty(&call->rx_queue)) 626 afs_deliver_to_call(call); 627 628 if (call->state >= AFS_CALL_COMPLETE && call->wait_mode) { 629 if (call->wait_mode->async_complete) 630 call->wait_mode->async_complete(call->reply, 631 call->error); 632 call->reply = NULL; 633 634 /* kill the call */ 635 rxrpc_kernel_end_call(call->rxcall); 636 call->rxcall = NULL; 637 if (call->type->destructor) 638 call->type->destructor(call); 639 640 /* we can't just delete the call because the work item may be 641 * queued */ 642 PREPARE_WORK(&call->async_work, afs_delete_async_call); 643 queue_work(afs_async_calls, &call->async_work); 644 } 645 646 _leave(""); 647 } 648 649 /* 650 * empty a socket buffer into a flat reply buffer 651 */ 652 void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb) 653 { 654 size_t len = skb->len; 655 656 if (skb_copy_bits(skb, 0, call->buffer + call->reply_size, len) < 0) 657 BUG(); 658 call->reply_size += len; 659 } 660 661 /* 662 * accept the backlog of incoming calls 663 */ 664 static void afs_collect_incoming_call(struct work_struct *work) 665 { 666 struct rxrpc_call *rxcall; 667 struct afs_call *call = NULL; 668 struct sk_buff *skb; 669 670 while ((skb = skb_dequeue(&afs_incoming_calls))) { 671 _debug("new call"); 672 673 /* don't need the notification */ 674 afs_free_skb(skb); 675 676 if (!call) { 677 call = kzalloc(sizeof(struct afs_call), GFP_KERNEL); 678 if (!call) { 679 rxrpc_kernel_reject_call(afs_socket); 680 return; 681 } 682 683 INIT_WORK(&call->async_work, afs_process_async_call); 684 call->wait_mode = &afs_async_incoming_call; 685 call->type = &afs_RXCMxxxx; 686 init_waitqueue_head(&call->waitq); 687 skb_queue_head_init(&call->rx_queue); 688 call->state = AFS_CALL_AWAIT_OP_ID; 689 690 _debug("CALL %p{%s} [%d]", 691 call, call->type->name, 692 atomic_read(&afs_outstanding_calls)); 693 atomic_inc(&afs_outstanding_calls); 694 } 695 696 rxcall = rxrpc_kernel_accept_call(afs_socket, 697 (unsigned long) call); 698 if (!IS_ERR(rxcall)) { 699 call->rxcall = rxcall; 700 call = NULL; 701 } 702 } 703 704 if (call) 705 afs_free_call(call); 706 } 707 708 /* 709 * grab the operation ID from an incoming cache manager call 710 */ 711 static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb, 712 bool last) 713 { 714 size_t len = skb->len; 715 void *oibuf = (void *) &call->operation_ID; 716 717 _enter("{%u},{%zu},%d", call->offset, len, last); 718 719 ASSERTCMP(call->offset, <, 4); 720 721 /* the operation ID forms the first four bytes of the request data */ 722 len = min_t(size_t, len, 4 - call->offset); 723 if (skb_copy_bits(skb, 0, oibuf + call->offset, len) < 0) 724 BUG(); 725 if (!pskb_pull(skb, len)) 726 BUG(); 727 call->offset += len; 728 729 if (call->offset < 4) { 730 if (last) { 731 _leave(" = -EBADMSG [op ID short]"); 732 return -EBADMSG; 733 } 734 _leave(" = 0 [incomplete]"); 735 return 0; 736 } 737 738 call->state = AFS_CALL_AWAIT_REQUEST; 739 740 /* ask the cache manager to route the call (it'll change the call type 741 * if successful) */ 742 if (!afs_cm_incoming_call(call)) 743 return -ENOTSUPP; 744 745 /* pass responsibility for the remainer of this message off to the 746 * cache manager op */ 747 return call->type->deliver(call, skb, last); 748 } 749 750 /* 751 * send an empty reply 752 */ 753 void afs_send_empty_reply(struct afs_call *call) 754 { 755 struct msghdr msg; 756 struct iovec iov[1]; 757 758 _enter(""); 759 760 iov[0].iov_base = NULL; 761 iov[0].iov_len = 0; 762 msg.msg_name = NULL; 763 msg.msg_namelen = 0; 764 msg.msg_iov = iov; 765 msg.msg_iovlen = 0; 766 msg.msg_control = NULL; 767 msg.msg_controllen = 0; 768 msg.msg_flags = 0; 769 770 call->state = AFS_CALL_AWAIT_ACK; 771 switch (rxrpc_kernel_send_data(call->rxcall, &msg, 0)) { 772 case 0: 773 _leave(" [replied]"); 774 return; 775 776 case -ENOMEM: 777 _debug("oom"); 778 rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT); 779 default: 780 rxrpc_kernel_end_call(call->rxcall); 781 call->rxcall = NULL; 782 call->type->destructor(call); 783 afs_free_call(call); 784 _leave(" [error]"); 785 return; 786 } 787 } 788 789 /* 790 * send a simple reply 791 */ 792 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 793 { 794 struct msghdr msg; 795 struct iovec iov[1]; 796 int n; 797 798 _enter(""); 799 800 iov[0].iov_base = (void *) buf; 801 iov[0].iov_len = len; 802 msg.msg_name = NULL; 803 msg.msg_namelen = 0; 804 msg.msg_iov = iov; 805 msg.msg_iovlen = 1; 806 msg.msg_control = NULL; 807 msg.msg_controllen = 0; 808 msg.msg_flags = 0; 809 810 call->state = AFS_CALL_AWAIT_ACK; 811 n = rxrpc_kernel_send_data(call->rxcall, &msg, len); 812 if (n >= 0) { 813 _leave(" [replied]"); 814 return; 815 } 816 if (n == -ENOMEM) { 817 _debug("oom"); 818 rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT); 819 } 820 rxrpc_kernel_end_call(call->rxcall); 821 call->rxcall = NULL; 822 call->type->destructor(call); 823 afs_free_call(call); 824 _leave(" [error]"); 825 } 826 827 /* 828 * extract a piece of data from the received data socket buffers 829 */ 830 int afs_extract_data(struct afs_call *call, struct sk_buff *skb, 831 bool last, void *buf, size_t count) 832 { 833 size_t len = skb->len; 834 835 _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count); 836 837 ASSERTCMP(call->offset, <, count); 838 839 len = min_t(size_t, len, count - call->offset); 840 if (skb_copy_bits(skb, 0, buf + call->offset, len) < 0 || 841 !pskb_pull(skb, len)) 842 BUG(); 843 call->offset += len; 844 845 if (call->offset < count) { 846 if (last) { 847 _leave(" = -EBADMSG [%d < %zu]", call->offset, count); 848 return -EBADMSG; 849 } 850 _leave(" = -EAGAIN"); 851 return -EAGAIN; 852 } 853 return 0; 854 } 855