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 <net/sock.h> 14 #include <net/af_rxrpc.h> 15 #include <rxrpc/packet.h> 16 #include "internal.h" 17 #include "afs_cm.h" 18 19 static struct socket *afs_socket; /* my RxRPC socket */ 20 static struct workqueue_struct *afs_async_calls; 21 static atomic_t afs_outstanding_calls; 22 static atomic_t afs_outstanding_skbs; 23 24 static void afs_wake_up_call_waiter(struct afs_call *); 25 static int afs_wait_for_call_to_complete(struct afs_call *); 26 static void afs_wake_up_async_call(struct afs_call *); 27 static int afs_dont_wait_for_call_to_complete(struct afs_call *); 28 static void afs_process_async_call(struct work_struct *); 29 static void afs_rx_interceptor(struct sock *, unsigned long, struct sk_buff *); 30 static int afs_deliver_cm_op_id(struct afs_call *, struct sk_buff *, bool); 31 32 /* synchronous call management */ 33 const struct afs_wait_mode afs_sync_call = { 34 .rx_wakeup = afs_wake_up_call_waiter, 35 .wait = afs_wait_for_call_to_complete, 36 }; 37 38 /* asynchronous call management */ 39 const struct afs_wait_mode afs_async_call = { 40 .rx_wakeup = afs_wake_up_async_call, 41 .wait = afs_dont_wait_for_call_to_complete, 42 }; 43 44 /* asynchronous incoming call management */ 45 static const struct afs_wait_mode afs_async_incoming_call = { 46 .rx_wakeup = afs_wake_up_async_call, 47 }; 48 49 /* asynchronous incoming call initial processing */ 50 static const struct afs_call_type afs_RXCMxxxx = { 51 .name = "CB.xxxx", 52 .deliver = afs_deliver_cm_op_id, 53 .abort_to_error = afs_abort_to_error, 54 }; 55 56 static void afs_collect_incoming_call(struct work_struct *); 57 58 static struct sk_buff_head afs_incoming_calls; 59 static DECLARE_WORK(afs_collect_incoming_call_work, afs_collect_incoming_call); 60 61 /* 62 * open an RxRPC socket and bind it to be a server for callback notifications 63 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 64 */ 65 int afs_open_socket(void) 66 { 67 struct sockaddr_rxrpc srx; 68 struct socket *socket; 69 int ret; 70 71 _enter(""); 72 73 skb_queue_head_init(&afs_incoming_calls); 74 75 afs_async_calls = create_singlethread_workqueue("kafsd"); 76 if (!afs_async_calls) { 77 _leave(" = -ENOMEM [wq]"); 78 return -ENOMEM; 79 } 80 81 ret = sock_create_kern(AF_RXRPC, SOCK_DGRAM, PF_INET, &socket); 82 if (ret < 0) { 83 destroy_workqueue(afs_async_calls); 84 _leave(" = %d [socket]", ret); 85 return ret; 86 } 87 88 socket->sk->sk_allocation = GFP_NOFS; 89 90 /* bind the callback manager's address to make this a server socket */ 91 srx.srx_family = AF_RXRPC; 92 srx.srx_service = CM_SERVICE; 93 srx.transport_type = SOCK_DGRAM; 94 srx.transport_len = sizeof(srx.transport.sin); 95 srx.transport.sin.sin_family = AF_INET; 96 srx.transport.sin.sin_port = htons(AFS_CM_PORT); 97 memset(&srx.transport.sin.sin_addr, 0, 98 sizeof(srx.transport.sin.sin_addr)); 99 100 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 101 if (ret < 0) { 102 sock_release(socket); 103 destroy_workqueue(afs_async_calls); 104 _leave(" = %d [bind]", ret); 105 return ret; 106 } 107 108 rxrpc_kernel_intercept_rx_messages(socket, afs_rx_interceptor); 109 110 afs_socket = socket; 111 _leave(" = 0"); 112 return 0; 113 } 114 115 /* 116 * close the RxRPC socket AFS was using 117 */ 118 void afs_close_socket(void) 119 { 120 _enter(""); 121 122 sock_release(afs_socket); 123 124 _debug("dework"); 125 destroy_workqueue(afs_async_calls); 126 127 ASSERTCMP(atomic_read(&afs_outstanding_skbs), ==, 0); 128 ASSERTCMP(atomic_read(&afs_outstanding_calls), ==, 0); 129 _leave(""); 130 } 131 132 /* 133 * note that the data in a socket buffer is now delivered and that the buffer 134 * should be freed 135 */ 136 static void afs_data_delivered(struct sk_buff *skb) 137 { 138 if (!skb) { 139 _debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs)); 140 dump_stack(); 141 } else { 142 _debug("DLVR %p{%u} [%d]", 143 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 144 if (atomic_dec_return(&afs_outstanding_skbs) == -1) 145 BUG(); 146 rxrpc_kernel_data_delivered(skb); 147 } 148 } 149 150 /* 151 * free a socket buffer 152 */ 153 static void afs_free_skb(struct sk_buff *skb) 154 { 155 if (!skb) { 156 _debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs)); 157 dump_stack(); 158 } else { 159 _debug("FREE %p{%u} [%d]", 160 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 161 if (atomic_dec_return(&afs_outstanding_skbs) == -1) 162 BUG(); 163 rxrpc_kernel_free_skb(skb); 164 } 165 } 166 167 /* 168 * free a call 169 */ 170 static void afs_free_call(struct afs_call *call) 171 { 172 _debug("DONE %p{%s} [%d]", 173 call, call->type->name, atomic_read(&afs_outstanding_calls)); 174 if (atomic_dec_return(&afs_outstanding_calls) == -1) 175 BUG(); 176 177 ASSERTCMP(call->rxcall, ==, NULL); 178 ASSERT(!work_pending(&call->async_work)); 179 ASSERT(skb_queue_empty(&call->rx_queue)); 180 ASSERT(call->type->name != NULL); 181 182 kfree(call->request); 183 kfree(call); 184 } 185 186 /* 187 * allocate a call with flat request and reply buffers 188 */ 189 struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, 190 size_t request_size, size_t reply_size) 191 { 192 struct afs_call *call; 193 194 call = kzalloc(sizeof(*call), GFP_NOFS); 195 if (!call) 196 goto nomem_call; 197 198 _debug("CALL %p{%s} [%d]", 199 call, type->name, atomic_read(&afs_outstanding_calls)); 200 atomic_inc(&afs_outstanding_calls); 201 202 call->type = type; 203 call->request_size = request_size; 204 call->reply_max = reply_size; 205 206 if (request_size) { 207 call->request = kmalloc(request_size, GFP_NOFS); 208 if (!call->request) 209 goto nomem_free; 210 } 211 212 if (reply_size) { 213 call->buffer = kmalloc(reply_size, GFP_NOFS); 214 if (!call->buffer) 215 goto nomem_free; 216 } 217 218 init_waitqueue_head(&call->waitq); 219 skb_queue_head_init(&call->rx_queue); 220 return call; 221 222 nomem_free: 223 afs_free_call(call); 224 nomem_call: 225 return NULL; 226 } 227 228 /* 229 * clean up a call with flat buffer 230 */ 231 void afs_flat_call_destructor(struct afs_call *call) 232 { 233 _enter(""); 234 235 kfree(call->request); 236 call->request = NULL; 237 kfree(call->buffer); 238 call->buffer = NULL; 239 } 240 241 /* 242 * attach the data from a bunch of pages on an inode to a call 243 */ 244 static int afs_send_pages(struct afs_call *call, struct msghdr *msg, 245 struct kvec *iov) 246 { 247 struct page *pages[8]; 248 unsigned count, n, loop, offset, to; 249 pgoff_t first = call->first, last = call->last; 250 int ret; 251 252 _enter(""); 253 254 offset = call->first_offset; 255 call->first_offset = 0; 256 257 do { 258 _debug("attach %lx-%lx", first, last); 259 260 count = last - first + 1; 261 if (count > ARRAY_SIZE(pages)) 262 count = ARRAY_SIZE(pages); 263 n = find_get_pages_contig(call->mapping, first, count, pages); 264 ASSERTCMP(n, ==, count); 265 266 loop = 0; 267 do { 268 msg->msg_flags = 0; 269 to = PAGE_SIZE; 270 if (first + loop >= last) 271 to = call->last_to; 272 else 273 msg->msg_flags = MSG_MORE; 274 iov->iov_base = kmap(pages[loop]) + offset; 275 iov->iov_len = to - offset; 276 offset = 0; 277 278 _debug("- range %u-%u%s", 279 offset, to, msg->msg_flags ? " [more]" : ""); 280 msg->msg_iov = (struct iovec *) iov; 281 msg->msg_iovlen = 1; 282 283 /* have to change the state *before* sending the last 284 * packet as RxRPC might give us the reply before it 285 * returns from sending the request */ 286 if (first + loop >= last) 287 call->state = AFS_CALL_AWAIT_REPLY; 288 ret = rxrpc_kernel_send_data(call->rxcall, msg, 289 to - offset); 290 kunmap(pages[loop]); 291 if (ret < 0) 292 break; 293 } while (++loop < count); 294 first += count; 295 296 for (loop = 0; loop < count; loop++) 297 put_page(pages[loop]); 298 if (ret < 0) 299 break; 300 } while (first <= last); 301 302 _leave(" = %d", ret); 303 return ret; 304 } 305 306 /* 307 * initiate a call 308 */ 309 int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, 310 const struct afs_wait_mode *wait_mode) 311 { 312 struct sockaddr_rxrpc srx; 313 struct rxrpc_call *rxcall; 314 struct msghdr msg; 315 struct kvec iov[1]; 316 int ret; 317 318 _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); 319 320 ASSERT(call->type != NULL); 321 ASSERT(call->type->name != NULL); 322 323 _debug("____MAKE %p{%s,%x} [%d]____", 324 call, call->type->name, key_serial(call->key), 325 atomic_read(&afs_outstanding_calls)); 326 327 call->wait_mode = wait_mode; 328 INIT_WORK(&call->async_work, afs_process_async_call); 329 330 memset(&srx, 0, sizeof(srx)); 331 srx.srx_family = AF_RXRPC; 332 srx.srx_service = call->service_id; 333 srx.transport_type = SOCK_DGRAM; 334 srx.transport_len = sizeof(srx.transport.sin); 335 srx.transport.sin.sin_family = AF_INET; 336 srx.transport.sin.sin_port = call->port; 337 memcpy(&srx.transport.sin.sin_addr, addr, 4); 338 339 /* create a call */ 340 rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key, 341 (unsigned long) call, gfp); 342 call->key = NULL; 343 if (IS_ERR(rxcall)) { 344 ret = PTR_ERR(rxcall); 345 goto error_kill_call; 346 } 347 348 call->rxcall = rxcall; 349 350 /* send the request */ 351 iov[0].iov_base = call->request; 352 iov[0].iov_len = call->request_size; 353 354 msg.msg_name = NULL; 355 msg.msg_namelen = 0; 356 msg.msg_iov = (struct iovec *) iov; 357 msg.msg_iovlen = 1; 358 msg.msg_control = NULL; 359 msg.msg_controllen = 0; 360 msg.msg_flags = (call->send_pages ? MSG_MORE : 0); 361 362 /* have to change the state *before* sending the last packet as RxRPC 363 * might give us the reply before it returns from sending the 364 * request */ 365 if (!call->send_pages) 366 call->state = AFS_CALL_AWAIT_REPLY; 367 ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size); 368 if (ret < 0) 369 goto error_do_abort; 370 371 if (call->send_pages) { 372 ret = afs_send_pages(call, &msg, iov); 373 if (ret < 0) 374 goto error_do_abort; 375 } 376 377 /* at this point, an async call may no longer exist as it may have 378 * already completed */ 379 return wait_mode->wait(call); 380 381 error_do_abort: 382 rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT); 383 rxrpc_kernel_end_call(rxcall); 384 call->rxcall = NULL; 385 error_kill_call: 386 call->type->destructor(call); 387 afs_free_call(call); 388 _leave(" = %d", ret); 389 return ret; 390 } 391 392 /* 393 * handles intercepted messages that were arriving in the socket's Rx queue 394 * - called with the socket receive queue lock held to ensure message ordering 395 * - called with softirqs disabled 396 */ 397 static void afs_rx_interceptor(struct sock *sk, unsigned long user_call_ID, 398 struct sk_buff *skb) 399 { 400 struct afs_call *call = (struct afs_call *) user_call_ID; 401 402 _enter("%p,,%u", call, skb->mark); 403 404 _debug("ICPT %p{%u} [%d]", 405 skb, skb->mark, atomic_read(&afs_outstanding_skbs)); 406 407 ASSERTCMP(sk, ==, afs_socket->sk); 408 atomic_inc(&afs_outstanding_skbs); 409 410 if (!call) { 411 /* its an incoming call for our callback service */ 412 skb_queue_tail(&afs_incoming_calls, skb); 413 schedule_work(&afs_collect_incoming_call_work); 414 } else { 415 /* route the messages directly to the appropriate call */ 416 skb_queue_tail(&call->rx_queue, skb); 417 call->wait_mode->rx_wakeup(call); 418 } 419 420 _leave(""); 421 } 422 423 /* 424 * deliver messages to a call 425 */ 426 static void afs_deliver_to_call(struct afs_call *call) 427 { 428 struct sk_buff *skb; 429 bool last; 430 u32 abort_code; 431 int ret; 432 433 _enter(""); 434 435 while ((call->state == AFS_CALL_AWAIT_REPLY || 436 call->state == AFS_CALL_AWAIT_OP_ID || 437 call->state == AFS_CALL_AWAIT_REQUEST || 438 call->state == AFS_CALL_AWAIT_ACK) && 439 (skb = skb_dequeue(&call->rx_queue))) { 440 switch (skb->mark) { 441 case RXRPC_SKB_MARK_DATA: 442 _debug("Rcv DATA"); 443 last = rxrpc_kernel_is_data_last(skb); 444 ret = call->type->deliver(call, skb, last); 445 switch (ret) { 446 case 0: 447 if (last && 448 call->state == AFS_CALL_AWAIT_REPLY) 449 call->state = AFS_CALL_COMPLETE; 450 break; 451 case -ENOTCONN: 452 abort_code = RX_CALL_DEAD; 453 goto do_abort; 454 case -ENOTSUPP: 455 abort_code = RX_INVALID_OPERATION; 456 goto do_abort; 457 default: 458 abort_code = RXGEN_CC_UNMARSHAL; 459 if (call->state != AFS_CALL_AWAIT_REPLY) 460 abort_code = RXGEN_SS_UNMARSHAL; 461 do_abort: 462 rxrpc_kernel_abort_call(call->rxcall, 463 abort_code); 464 call->error = ret; 465 call->state = AFS_CALL_ERROR; 466 break; 467 } 468 afs_data_delivered(skb); 469 skb = NULL; 470 continue; 471 case RXRPC_SKB_MARK_FINAL_ACK: 472 _debug("Rcv ACK"); 473 call->state = AFS_CALL_COMPLETE; 474 break; 475 case RXRPC_SKB_MARK_BUSY: 476 _debug("Rcv BUSY"); 477 call->error = -EBUSY; 478 call->state = AFS_CALL_BUSY; 479 break; 480 case RXRPC_SKB_MARK_REMOTE_ABORT: 481 abort_code = rxrpc_kernel_get_abort_code(skb); 482 call->error = call->type->abort_to_error(abort_code); 483 call->state = AFS_CALL_ABORTED; 484 _debug("Rcv ABORT %u -> %d", abort_code, call->error); 485 break; 486 case RXRPC_SKB_MARK_NET_ERROR: 487 call->error = -rxrpc_kernel_get_error_number(skb); 488 call->state = AFS_CALL_ERROR; 489 _debug("Rcv NET ERROR %d", call->error); 490 break; 491 case RXRPC_SKB_MARK_LOCAL_ERROR: 492 call->error = -rxrpc_kernel_get_error_number(skb); 493 call->state = AFS_CALL_ERROR; 494 _debug("Rcv LOCAL ERROR %d", call->error); 495 break; 496 default: 497 BUG(); 498 break; 499 } 500 501 afs_free_skb(skb); 502 } 503 504 /* make sure the queue is empty if the call is done with (we might have 505 * aborted the call early because of an unmarshalling error) */ 506 if (call->state >= AFS_CALL_COMPLETE) { 507 while ((skb = skb_dequeue(&call->rx_queue))) 508 afs_free_skb(skb); 509 if (call->incoming) { 510 rxrpc_kernel_end_call(call->rxcall); 511 call->rxcall = NULL; 512 call->type->destructor(call); 513 afs_free_call(call); 514 } 515 } 516 517 _leave(""); 518 } 519 520 /* 521 * wait synchronously for a call to complete 522 */ 523 static int afs_wait_for_call_to_complete(struct afs_call *call) 524 { 525 struct sk_buff *skb; 526 int ret; 527 528 DECLARE_WAITQUEUE(myself, current); 529 530 _enter(""); 531 532 add_wait_queue(&call->waitq, &myself); 533 for (;;) { 534 set_current_state(TASK_INTERRUPTIBLE); 535 536 /* deliver any messages that are in the queue */ 537 if (!skb_queue_empty(&call->rx_queue)) { 538 __set_current_state(TASK_RUNNING); 539 afs_deliver_to_call(call); 540 continue; 541 } 542 543 ret = call->error; 544 if (call->state >= AFS_CALL_COMPLETE) 545 break; 546 ret = -EINTR; 547 if (signal_pending(current)) 548 break; 549 schedule(); 550 } 551 552 remove_wait_queue(&call->waitq, &myself); 553 __set_current_state(TASK_RUNNING); 554 555 /* kill the call */ 556 if (call->state < AFS_CALL_COMPLETE) { 557 _debug("call incomplete"); 558 rxrpc_kernel_abort_call(call->rxcall, RX_CALL_DEAD); 559 while ((skb = skb_dequeue(&call->rx_queue))) 560 afs_free_skb(skb); 561 } 562 563 _debug("call complete"); 564 rxrpc_kernel_end_call(call->rxcall); 565 call->rxcall = NULL; 566 call->type->destructor(call); 567 afs_free_call(call); 568 _leave(" = %d", ret); 569 return ret; 570 } 571 572 /* 573 * wake up a waiting call 574 */ 575 static void afs_wake_up_call_waiter(struct afs_call *call) 576 { 577 wake_up(&call->waitq); 578 } 579 580 /* 581 * wake up an asynchronous call 582 */ 583 static void afs_wake_up_async_call(struct afs_call *call) 584 { 585 _enter(""); 586 queue_work(afs_async_calls, &call->async_work); 587 } 588 589 /* 590 * put a call into asynchronous mode 591 * - mustn't touch the call descriptor as the call my have completed by the 592 * time we get here 593 */ 594 static int afs_dont_wait_for_call_to_complete(struct afs_call *call) 595 { 596 _enter(""); 597 return -EINPROGRESS; 598 } 599 600 /* 601 * delete an asynchronous call 602 */ 603 static void afs_delete_async_call(struct work_struct *work) 604 { 605 struct afs_call *call = 606 container_of(work, struct afs_call, async_work); 607 608 _enter(""); 609 610 afs_free_call(call); 611 612 _leave(""); 613 } 614 615 /* 616 * perform processing on an asynchronous call 617 * - on a multiple-thread workqueue this work item may try to run on several 618 * CPUs at the same time 619 */ 620 static void afs_process_async_call(struct work_struct *work) 621 { 622 struct afs_call *call = 623 container_of(work, struct afs_call, async_work); 624 625 _enter(""); 626 627 if (!skb_queue_empty(&call->rx_queue)) 628 afs_deliver_to_call(call); 629 630 if (call->state >= AFS_CALL_COMPLETE && call->wait_mode) { 631 if (call->wait_mode->async_complete) 632 call->wait_mode->async_complete(call->reply, 633 call->error); 634 call->reply = NULL; 635 636 /* kill the call */ 637 rxrpc_kernel_end_call(call->rxcall); 638 call->rxcall = NULL; 639 if (call->type->destructor) 640 call->type->destructor(call); 641 642 /* we can't just delete the call because the work item may be 643 * queued */ 644 PREPARE_WORK(&call->async_work, afs_delete_async_call); 645 queue_work(afs_async_calls, &call->async_work); 646 } 647 648 _leave(""); 649 } 650 651 /* 652 * empty a socket buffer into a flat reply buffer 653 */ 654 void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb) 655 { 656 size_t len = skb->len; 657 658 if (skb_copy_bits(skb, 0, call->buffer + call->reply_size, len) < 0) 659 BUG(); 660 call->reply_size += len; 661 } 662 663 /* 664 * accept the backlog of incoming calls 665 */ 666 static void afs_collect_incoming_call(struct work_struct *work) 667 { 668 struct rxrpc_call *rxcall; 669 struct afs_call *call = NULL; 670 struct sk_buff *skb; 671 672 while ((skb = skb_dequeue(&afs_incoming_calls))) { 673 _debug("new call"); 674 675 /* don't need the notification */ 676 afs_free_skb(skb); 677 678 if (!call) { 679 call = kzalloc(sizeof(struct afs_call), GFP_KERNEL); 680 if (!call) { 681 rxrpc_kernel_reject_call(afs_socket); 682 return; 683 } 684 685 INIT_WORK(&call->async_work, afs_process_async_call); 686 call->wait_mode = &afs_async_incoming_call; 687 call->type = &afs_RXCMxxxx; 688 init_waitqueue_head(&call->waitq); 689 skb_queue_head_init(&call->rx_queue); 690 call->state = AFS_CALL_AWAIT_OP_ID; 691 692 _debug("CALL %p{%s} [%d]", 693 call, call->type->name, 694 atomic_read(&afs_outstanding_calls)); 695 atomic_inc(&afs_outstanding_calls); 696 } 697 698 rxcall = rxrpc_kernel_accept_call(afs_socket, 699 (unsigned long) call); 700 if (!IS_ERR(rxcall)) { 701 call->rxcall = rxcall; 702 call = NULL; 703 } 704 } 705 706 if (call) 707 afs_free_call(call); 708 } 709 710 /* 711 * grab the operation ID from an incoming cache manager call 712 */ 713 static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb, 714 bool last) 715 { 716 size_t len = skb->len; 717 void *oibuf = (void *) &call->operation_ID; 718 719 _enter("{%u},{%zu},%d", call->offset, len, last); 720 721 ASSERTCMP(call->offset, <, 4); 722 723 /* the operation ID forms the first four bytes of the request data */ 724 len = min_t(size_t, len, 4 - call->offset); 725 if (skb_copy_bits(skb, 0, oibuf + call->offset, len) < 0) 726 BUG(); 727 if (!pskb_pull(skb, len)) 728 BUG(); 729 call->offset += len; 730 731 if (call->offset < 4) { 732 if (last) { 733 _leave(" = -EBADMSG [op ID short]"); 734 return -EBADMSG; 735 } 736 _leave(" = 0 [incomplete]"); 737 return 0; 738 } 739 740 call->state = AFS_CALL_AWAIT_REQUEST; 741 742 /* ask the cache manager to route the call (it'll change the call type 743 * if successful) */ 744 if (!afs_cm_incoming_call(call)) 745 return -ENOTSUPP; 746 747 /* pass responsibility for the remainer of this message off to the 748 * cache manager op */ 749 return call->type->deliver(call, skb, last); 750 } 751 752 /* 753 * send an empty reply 754 */ 755 void afs_send_empty_reply(struct afs_call *call) 756 { 757 struct msghdr msg; 758 struct iovec iov[1]; 759 760 _enter(""); 761 762 iov[0].iov_base = NULL; 763 iov[0].iov_len = 0; 764 msg.msg_name = NULL; 765 msg.msg_namelen = 0; 766 msg.msg_iov = iov; 767 msg.msg_iovlen = 0; 768 msg.msg_control = NULL; 769 msg.msg_controllen = 0; 770 msg.msg_flags = 0; 771 772 call->state = AFS_CALL_AWAIT_ACK; 773 switch (rxrpc_kernel_send_data(call->rxcall, &msg, 0)) { 774 case 0: 775 _leave(" [replied]"); 776 return; 777 778 case -ENOMEM: 779 _debug("oom"); 780 rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT); 781 default: 782 rxrpc_kernel_end_call(call->rxcall); 783 call->rxcall = NULL; 784 call->type->destructor(call); 785 afs_free_call(call); 786 _leave(" [error]"); 787 return; 788 } 789 } 790 791 /* 792 * send a simple reply 793 */ 794 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 795 { 796 struct msghdr msg; 797 struct iovec iov[1]; 798 int n; 799 800 _enter(""); 801 802 iov[0].iov_base = (void *) buf; 803 iov[0].iov_len = len; 804 msg.msg_name = NULL; 805 msg.msg_namelen = 0; 806 msg.msg_iov = iov; 807 msg.msg_iovlen = 1; 808 msg.msg_control = NULL; 809 msg.msg_controllen = 0; 810 msg.msg_flags = 0; 811 812 call->state = AFS_CALL_AWAIT_ACK; 813 n = rxrpc_kernel_send_data(call->rxcall, &msg, len); 814 if (n >= 0) { 815 _leave(" [replied]"); 816 return; 817 } 818 if (n == -ENOMEM) { 819 _debug("oom"); 820 rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT); 821 } 822 rxrpc_kernel_end_call(call->rxcall); 823 call->rxcall = NULL; 824 call->type->destructor(call); 825 afs_free_call(call); 826 _leave(" [error]"); 827 } 828 829 /* 830 * extract a piece of data from the received data socket buffers 831 */ 832 int afs_extract_data(struct afs_call *call, struct sk_buff *skb, 833 bool last, void *buf, size_t count) 834 { 835 size_t len = skb->len; 836 837 _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count); 838 839 ASSERTCMP(call->offset, <, count); 840 841 len = min_t(size_t, len, count - call->offset); 842 if (skb_copy_bits(skb, 0, buf + call->offset, len) < 0 || 843 !pskb_pull(skb, len)) 844 BUG(); 845 call->offset += len; 846 847 if (call->offset < count) { 848 if (last) { 849 _leave(" = -EBADMSG [%d < %zu]", call->offset, count); 850 return -EBADMSG; 851 } 852 _leave(" = -EAGAIN"); 853 return -EAGAIN; 854 } 855 return 0; 856 } 857