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