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 #include "protocol_yfs.h" 20 21 struct workqueue_struct *afs_async_calls; 22 23 static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); 24 static long afs_wait_for_call_to_complete(struct afs_call *, struct afs_addr_cursor *); 25 static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); 26 static void afs_delete_async_call(struct work_struct *); 27 static void afs_process_async_call(struct work_struct *); 28 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long); 29 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long); 30 static int afs_deliver_cm_op_id(struct afs_call *); 31 32 /* asynchronous incoming call initial processing */ 33 static const struct afs_call_type afs_RXCMxxxx = { 34 .name = "CB.xxxx", 35 .deliver = afs_deliver_cm_op_id, 36 }; 37 38 /* 39 * open an RxRPC socket and bind it to be a server for callback notifications 40 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT 41 */ 42 int afs_open_socket(struct afs_net *net) 43 { 44 struct sockaddr_rxrpc srx; 45 struct socket *socket; 46 unsigned int min_level; 47 int ret; 48 49 _enter(""); 50 51 ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket); 52 if (ret < 0) 53 goto error_1; 54 55 socket->sk->sk_allocation = GFP_NOFS; 56 57 /* bind the callback manager's address to make this a server socket */ 58 memset(&srx, 0, sizeof(srx)); 59 srx.srx_family = AF_RXRPC; 60 srx.srx_service = CM_SERVICE; 61 srx.transport_type = SOCK_DGRAM; 62 srx.transport_len = sizeof(srx.transport.sin6); 63 srx.transport.sin6.sin6_family = AF_INET6; 64 srx.transport.sin6.sin6_port = htons(AFS_CM_PORT); 65 66 min_level = RXRPC_SECURITY_ENCRYPT; 67 ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_MIN_SECURITY_LEVEL, 68 (void *)&min_level, sizeof(min_level)); 69 if (ret < 0) 70 goto error_2; 71 72 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 73 if (ret == -EADDRINUSE) { 74 srx.transport.sin6.sin6_port = 0; 75 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 76 } 77 if (ret < 0) 78 goto error_2; 79 80 srx.srx_service = YFS_CM_SERVICE; 81 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); 82 if (ret < 0) 83 goto error_2; 84 85 /* Ideally, we'd turn on service upgrade here, but we can't because 86 * OpenAFS is buggy and leaks the userStatus field from packet to 87 * packet and between FS packets and CB packets - so if we try to do an 88 * upgrade on an FS packet, OpenAFS will leak that into the CB packet 89 * it sends back to us. 90 */ 91 92 rxrpc_kernel_new_call_notification(socket, afs_rx_new_call, 93 afs_rx_discard_new_call); 94 95 ret = kernel_listen(socket, INT_MAX); 96 if (ret < 0) 97 goto error_2; 98 99 net->socket = socket; 100 afs_charge_preallocation(&net->charge_preallocation_work); 101 _leave(" = 0"); 102 return 0; 103 104 error_2: 105 sock_release(socket); 106 error_1: 107 _leave(" = %d", ret); 108 return ret; 109 } 110 111 /* 112 * close the RxRPC socket AFS was using 113 */ 114 void afs_close_socket(struct afs_net *net) 115 { 116 _enter(""); 117 118 kernel_listen(net->socket, 0); 119 flush_workqueue(afs_async_calls); 120 121 if (net->spare_incoming_call) { 122 afs_put_call(net->spare_incoming_call); 123 net->spare_incoming_call = NULL; 124 } 125 126 _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls)); 127 wait_var_event(&net->nr_outstanding_calls, 128 !atomic_read(&net->nr_outstanding_calls)); 129 _debug("no outstanding calls"); 130 131 kernel_sock_shutdown(net->socket, SHUT_RDWR); 132 flush_workqueue(afs_async_calls); 133 sock_release(net->socket); 134 135 _debug("dework"); 136 _leave(""); 137 } 138 139 /* 140 * Allocate a call. 141 */ 142 static struct afs_call *afs_alloc_call(struct afs_net *net, 143 const struct afs_call_type *type, 144 gfp_t gfp) 145 { 146 struct afs_call *call; 147 int o; 148 149 call = kzalloc(sizeof(*call), gfp); 150 if (!call) 151 return NULL; 152 153 call->type = type; 154 call->net = net; 155 call->debug_id = atomic_inc_return(&rxrpc_debug_id); 156 atomic_set(&call->usage, 1); 157 INIT_WORK(&call->async_work, afs_process_async_call); 158 init_waitqueue_head(&call->waitq); 159 spin_lock_init(&call->state_lock); 160 call->_iter = &call->iter; 161 162 o = atomic_inc_return(&net->nr_outstanding_calls); 163 trace_afs_call(call, afs_call_trace_alloc, 1, o, 164 __builtin_return_address(0)); 165 return call; 166 } 167 168 /* 169 * Dispose of a reference on a call. 170 */ 171 void afs_put_call(struct afs_call *call) 172 { 173 struct afs_net *net = call->net; 174 int n = atomic_dec_return(&call->usage); 175 int o = atomic_read(&net->nr_outstanding_calls); 176 177 trace_afs_call(call, afs_call_trace_put, n + 1, o, 178 __builtin_return_address(0)); 179 180 ASSERTCMP(n, >=, 0); 181 if (n == 0) { 182 ASSERT(!work_pending(&call->async_work)); 183 ASSERT(call->type->name != NULL); 184 185 if (call->rxcall) { 186 rxrpc_kernel_end_call(net->socket, call->rxcall); 187 call->rxcall = NULL; 188 } 189 if (call->type->destructor) 190 call->type->destructor(call); 191 192 afs_put_server(call->net, call->cm_server); 193 afs_put_cb_interest(call->net, call->cbi); 194 afs_put_addrlist(call->alist); 195 kfree(call->request); 196 197 trace_afs_call(call, afs_call_trace_free, 0, o, 198 __builtin_return_address(0)); 199 kfree(call); 200 201 o = atomic_dec_return(&net->nr_outstanding_calls); 202 if (o == 0) 203 wake_up_var(&net->nr_outstanding_calls); 204 } 205 } 206 207 static struct afs_call *afs_get_call(struct afs_call *call, 208 enum afs_call_trace why) 209 { 210 int u = atomic_inc_return(&call->usage); 211 212 trace_afs_call(call, why, u, 213 atomic_read(&call->net->nr_outstanding_calls), 214 __builtin_return_address(0)); 215 return call; 216 } 217 218 /* 219 * Queue the call for actual work. 220 */ 221 static void afs_queue_call_work(struct afs_call *call) 222 { 223 if (call->type->work) { 224 INIT_WORK(&call->work, call->type->work); 225 226 afs_get_call(call, afs_call_trace_work); 227 if (!queue_work(afs_wq, &call->work)) 228 afs_put_call(call); 229 } 230 } 231 232 /* 233 * allocate a call with flat request and reply buffers 234 */ 235 struct afs_call *afs_alloc_flat_call(struct afs_net *net, 236 const struct afs_call_type *type, 237 size_t request_size, size_t reply_max) 238 { 239 struct afs_call *call; 240 241 call = afs_alloc_call(net, type, GFP_NOFS); 242 if (!call) 243 goto nomem_call; 244 245 if (request_size) { 246 call->request_size = request_size; 247 call->request = kmalloc(request_size, GFP_NOFS); 248 if (!call->request) 249 goto nomem_free; 250 } 251 252 if (reply_max) { 253 call->reply_max = reply_max; 254 call->buffer = kmalloc(reply_max, GFP_NOFS); 255 if (!call->buffer) 256 goto nomem_free; 257 } 258 259 afs_extract_to_buf(call, call->reply_max); 260 call->operation_ID = type->op; 261 init_waitqueue_head(&call->waitq); 262 return call; 263 264 nomem_free: 265 afs_put_call(call); 266 nomem_call: 267 return NULL; 268 } 269 270 /* 271 * clean up a call with flat buffer 272 */ 273 void afs_flat_call_destructor(struct afs_call *call) 274 { 275 _enter(""); 276 277 kfree(call->request); 278 call->request = NULL; 279 kfree(call->buffer); 280 call->buffer = NULL; 281 } 282 283 #define AFS_BVEC_MAX 8 284 285 /* 286 * Load the given bvec with the next few pages. 287 */ 288 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg, 289 struct bio_vec *bv, pgoff_t first, pgoff_t last, 290 unsigned offset) 291 { 292 struct page *pages[AFS_BVEC_MAX]; 293 unsigned int nr, n, i, to, bytes = 0; 294 295 nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX); 296 n = find_get_pages_contig(call->mapping, first, nr, pages); 297 ASSERTCMP(n, ==, nr); 298 299 msg->msg_flags |= MSG_MORE; 300 for (i = 0; i < nr; i++) { 301 to = PAGE_SIZE; 302 if (first + i >= last) { 303 to = call->last_to; 304 msg->msg_flags &= ~MSG_MORE; 305 } 306 bv[i].bv_page = pages[i]; 307 bv[i].bv_len = to - offset; 308 bv[i].bv_offset = offset; 309 bytes += to - offset; 310 offset = 0; 311 } 312 313 iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes); 314 } 315 316 /* 317 * Advance the AFS call state when the RxRPC call ends the transmit phase. 318 */ 319 static void afs_notify_end_request_tx(struct sock *sock, 320 struct rxrpc_call *rxcall, 321 unsigned long call_user_ID) 322 { 323 struct afs_call *call = (struct afs_call *)call_user_ID; 324 325 afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY); 326 } 327 328 /* 329 * attach the data from a bunch of pages on an inode to a call 330 */ 331 static int afs_send_pages(struct afs_call *call, struct msghdr *msg) 332 { 333 struct bio_vec bv[AFS_BVEC_MAX]; 334 unsigned int bytes, nr, loop, offset; 335 pgoff_t first = call->first, last = call->last; 336 int ret; 337 338 offset = call->first_offset; 339 call->first_offset = 0; 340 341 do { 342 afs_load_bvec(call, msg, bv, first, last, offset); 343 trace_afs_send_pages(call, msg, first, last, offset); 344 345 offset = 0; 346 bytes = msg->msg_iter.count; 347 nr = msg->msg_iter.nr_segs; 348 349 ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg, 350 bytes, afs_notify_end_request_tx); 351 for (loop = 0; loop < nr; loop++) 352 put_page(bv[loop].bv_page); 353 if (ret < 0) 354 break; 355 356 first += nr; 357 } while (first <= last); 358 359 trace_afs_sent_pages(call, call->first, last, first, ret); 360 return ret; 361 } 362 363 /* 364 * initiate a call 365 */ 366 long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, 367 gfp_t gfp, bool async) 368 { 369 struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index]; 370 struct rxrpc_call *rxcall; 371 struct msghdr msg; 372 struct kvec iov[1]; 373 s64 tx_total_len; 374 int ret; 375 376 _enter(",{%pISp},", &srx->transport); 377 378 ASSERT(call->type != NULL); 379 ASSERT(call->type->name != NULL); 380 381 _debug("____MAKE %p{%s,%x} [%d]____", 382 call, call->type->name, key_serial(call->key), 383 atomic_read(&call->net->nr_outstanding_calls)); 384 385 call->async = async; 386 call->addr_ix = ac->index; 387 call->alist = afs_get_addrlist(ac->alist); 388 389 /* Work out the length we're going to transmit. This is awkward for 390 * calls such as FS.StoreData where there's an extra injection of data 391 * after the initial fixed part. 392 */ 393 tx_total_len = call->request_size; 394 if (call->send_pages) { 395 if (call->last == call->first) { 396 tx_total_len += call->last_to - call->first_offset; 397 } else { 398 /* It looks mathematically like you should be able to 399 * combine the following lines with the ones above, but 400 * unsigned arithmetic is fun when it wraps... 401 */ 402 tx_total_len += PAGE_SIZE - call->first_offset; 403 tx_total_len += call->last_to; 404 tx_total_len += (call->last - call->first - 1) * PAGE_SIZE; 405 } 406 } 407 408 /* If the call is going to be asynchronous, we need an extra ref for 409 * the call to hold itself so the caller need not hang on to its ref. 410 */ 411 if (call->async) 412 afs_get_call(call, afs_call_trace_get); 413 414 /* create a call */ 415 rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key, 416 (unsigned long)call, 417 tx_total_len, gfp, 418 (async ? 419 afs_wake_up_async_call : 420 afs_wake_up_call_waiter), 421 call->upgrade, 422 call->debug_id); 423 if (IS_ERR(rxcall)) { 424 ret = PTR_ERR(rxcall); 425 call->error = ret; 426 goto error_kill_call; 427 } 428 429 call->rxcall = rxcall; 430 431 /* send the request */ 432 iov[0].iov_base = call->request; 433 iov[0].iov_len = call->request_size; 434 435 msg.msg_name = NULL; 436 msg.msg_namelen = 0; 437 iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size); 438 msg.msg_control = NULL; 439 msg.msg_controllen = 0; 440 msg.msg_flags = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0); 441 442 ret = rxrpc_kernel_send_data(call->net->socket, rxcall, 443 &msg, call->request_size, 444 afs_notify_end_request_tx); 445 if (ret < 0) 446 goto error_do_abort; 447 448 if (call->send_pages) { 449 ret = afs_send_pages(call, &msg); 450 if (ret < 0) 451 goto error_do_abort; 452 } 453 454 /* Note that at this point, we may have received the reply or an abort 455 * - and an asynchronous call may already have completed. 456 */ 457 if (call->async) { 458 afs_put_call(call); 459 return -EINPROGRESS; 460 } 461 462 return afs_wait_for_call_to_complete(call, ac); 463 464 error_do_abort: 465 if (ret != -ECONNABORTED) { 466 rxrpc_kernel_abort_call(call->net->socket, rxcall, 467 RX_USER_ABORT, ret, "KSD"); 468 } else { 469 iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0); 470 rxrpc_kernel_recv_data(call->net->socket, rxcall, 471 &msg.msg_iter, false, 472 &call->abort_code, &call->service_id); 473 ac->abort_code = call->abort_code; 474 ac->responded = true; 475 } 476 call->error = ret; 477 trace_afs_call_done(call); 478 error_kill_call: 479 if (call->type->done) 480 call->type->done(call); 481 482 /* We need to dispose of the extra ref we grabbed for an async call. 483 * The call, however, might be queued on afs_async_calls and we need to 484 * make sure we don't get any more notifications that might requeue it. 485 */ 486 if (call->rxcall) { 487 rxrpc_kernel_end_call(call->net->socket, call->rxcall); 488 call->rxcall = NULL; 489 } 490 if (call->async) { 491 if (cancel_work_sync(&call->async_work)) 492 afs_put_call(call); 493 afs_put_call(call); 494 } 495 496 ac->error = ret; 497 call->state = AFS_CALL_COMPLETE; 498 afs_put_call(call); 499 _leave(" = %d", ret); 500 return ret; 501 } 502 503 /* 504 * deliver messages to a call 505 */ 506 static void afs_deliver_to_call(struct afs_call *call) 507 { 508 enum afs_call_state state; 509 u32 abort_code, remote_abort = 0; 510 int ret; 511 512 _enter("%s", call->type->name); 513 514 while (state = READ_ONCE(call->state), 515 state == AFS_CALL_CL_AWAIT_REPLY || 516 state == AFS_CALL_SV_AWAIT_OP_ID || 517 state == AFS_CALL_SV_AWAIT_REQUEST || 518 state == AFS_CALL_SV_AWAIT_ACK 519 ) { 520 if (state == AFS_CALL_SV_AWAIT_ACK) { 521 iov_iter_kvec(&call->iter, READ, NULL, 0, 0); 522 ret = rxrpc_kernel_recv_data(call->net->socket, 523 call->rxcall, &call->iter, 524 false, &remote_abort, 525 &call->service_id); 526 trace_afs_receive_data(call, &call->iter, false, ret); 527 528 if (ret == -EINPROGRESS || ret == -EAGAIN) 529 return; 530 if (ret < 0 || ret == 1) { 531 if (ret == 1) 532 ret = 0; 533 goto call_complete; 534 } 535 return; 536 } 537 538 if (call->want_reply_time && 539 rxrpc_kernel_get_reply_time(call->net->socket, 540 call->rxcall, 541 &call->reply_time)) 542 call->want_reply_time = false; 543 544 ret = call->type->deliver(call); 545 state = READ_ONCE(call->state); 546 switch (ret) { 547 case 0: 548 afs_queue_call_work(call); 549 if (state == AFS_CALL_CL_PROC_REPLY) { 550 if (call->cbi) 551 set_bit(AFS_SERVER_FL_MAY_HAVE_CB, 552 &call->cbi->server->flags); 553 goto call_complete; 554 } 555 ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY); 556 goto done; 557 case -EINPROGRESS: 558 case -EAGAIN: 559 goto out; 560 case -ECONNABORTED: 561 ASSERTCMP(state, ==, AFS_CALL_COMPLETE); 562 goto done; 563 case -ENOTSUPP: 564 abort_code = RXGEN_OPCODE; 565 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 566 abort_code, ret, "KIV"); 567 goto local_abort; 568 case -EIO: 569 pr_err("kAFS: Call %u in bad state %u\n", 570 call->debug_id, state); 571 /* Fall through */ 572 case -ENODATA: 573 case -EBADMSG: 574 case -EMSGSIZE: 575 abort_code = RXGEN_CC_UNMARSHAL; 576 if (state != AFS_CALL_CL_AWAIT_REPLY) 577 abort_code = RXGEN_SS_UNMARSHAL; 578 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 579 abort_code, ret, "KUM"); 580 goto local_abort; 581 default: 582 abort_code = RX_USER_ABORT; 583 rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 584 abort_code, ret, "KER"); 585 goto local_abort; 586 } 587 } 588 589 done: 590 if (call->type->done) 591 call->type->done(call); 592 if (state == AFS_CALL_COMPLETE && call->incoming) 593 afs_put_call(call); 594 out: 595 _leave(""); 596 return; 597 598 local_abort: 599 abort_code = 0; 600 call_complete: 601 afs_set_call_complete(call, ret, remote_abort); 602 state = AFS_CALL_COMPLETE; 603 goto done; 604 } 605 606 /* 607 * wait synchronously for a call to complete 608 */ 609 static long afs_wait_for_call_to_complete(struct afs_call *call, 610 struct afs_addr_cursor *ac) 611 { 612 signed long rtt2, timeout; 613 long ret; 614 bool stalled = false; 615 u64 rtt; 616 u32 life, last_life; 617 bool rxrpc_complete = false; 618 619 DECLARE_WAITQUEUE(myself, current); 620 621 _enter(""); 622 623 rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall); 624 rtt2 = nsecs_to_jiffies64(rtt) * 2; 625 if (rtt2 < 2) 626 rtt2 = 2; 627 628 timeout = rtt2; 629 rxrpc_kernel_check_life(call->net->socket, call->rxcall, &last_life); 630 631 add_wait_queue(&call->waitq, &myself); 632 for (;;) { 633 set_current_state(TASK_UNINTERRUPTIBLE); 634 635 /* deliver any messages that are in the queue */ 636 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) && 637 call->need_attention) { 638 call->need_attention = false; 639 __set_current_state(TASK_RUNNING); 640 afs_deliver_to_call(call); 641 continue; 642 } 643 644 if (afs_check_call_state(call, AFS_CALL_COMPLETE)) 645 break; 646 647 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall, &life)) { 648 /* rxrpc terminated the call. */ 649 rxrpc_complete = true; 650 break; 651 } 652 653 if (timeout == 0 && 654 life == last_life && signal_pending(current)) { 655 if (stalled) 656 break; 657 __set_current_state(TASK_RUNNING); 658 rxrpc_kernel_probe_life(call->net->socket, call->rxcall); 659 timeout = rtt2; 660 stalled = true; 661 continue; 662 } 663 664 if (life != last_life) { 665 timeout = rtt2; 666 last_life = life; 667 stalled = false; 668 } 669 670 timeout = schedule_timeout(timeout); 671 } 672 673 remove_wait_queue(&call->waitq, &myself); 674 __set_current_state(TASK_RUNNING); 675 676 if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) { 677 if (rxrpc_complete) { 678 afs_set_call_complete(call, call->error, call->abort_code); 679 } else { 680 /* Kill off the call if it's still live. */ 681 _debug("call interrupted"); 682 if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall, 683 RX_USER_ABORT, -EINTR, "KWI")) 684 afs_set_call_complete(call, -EINTR, 0); 685 } 686 } 687 688 spin_lock_bh(&call->state_lock); 689 ac->abort_code = call->abort_code; 690 ac->error = call->error; 691 spin_unlock_bh(&call->state_lock); 692 693 ret = ac->error; 694 switch (ret) { 695 case 0: 696 if (call->ret_reply0) { 697 ret = (long)call->reply[0]; 698 call->reply[0] = NULL; 699 } 700 /* Fall through */ 701 case -ECONNABORTED: 702 ac->responded = true; 703 break; 704 } 705 706 _debug("call complete"); 707 afs_put_call(call); 708 _leave(" = %p", (void *)ret); 709 return ret; 710 } 711 712 /* 713 * wake up a waiting call 714 */ 715 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, 716 unsigned long call_user_ID) 717 { 718 struct afs_call *call = (struct afs_call *)call_user_ID; 719 720 call->need_attention = true; 721 wake_up(&call->waitq); 722 } 723 724 /* 725 * wake up an asynchronous call 726 */ 727 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, 728 unsigned long call_user_ID) 729 { 730 struct afs_call *call = (struct afs_call *)call_user_ID; 731 int u; 732 733 trace_afs_notify_call(rxcall, call); 734 call->need_attention = true; 735 736 u = atomic_fetch_add_unless(&call->usage, 1, 0); 737 if (u != 0) { 738 trace_afs_call(call, afs_call_trace_wake, u, 739 atomic_read(&call->net->nr_outstanding_calls), 740 __builtin_return_address(0)); 741 742 if (!queue_work(afs_async_calls, &call->async_work)) 743 afs_put_call(call); 744 } 745 } 746 747 /* 748 * Delete an asynchronous call. The work item carries a ref to the call struct 749 * that we need to release. 750 */ 751 static void afs_delete_async_call(struct work_struct *work) 752 { 753 struct afs_call *call = container_of(work, struct afs_call, async_work); 754 755 _enter(""); 756 757 afs_put_call(call); 758 759 _leave(""); 760 } 761 762 /* 763 * Perform I/O processing on an asynchronous call. The work item carries a ref 764 * to the call struct that we either need to release or to pass on. 765 */ 766 static void afs_process_async_call(struct work_struct *work) 767 { 768 struct afs_call *call = container_of(work, struct afs_call, async_work); 769 770 _enter(""); 771 772 if (call->state < AFS_CALL_COMPLETE && call->need_attention) { 773 call->need_attention = false; 774 afs_deliver_to_call(call); 775 } 776 777 if (call->state == AFS_CALL_COMPLETE) { 778 /* We have two refs to release - one from the alloc and one 779 * queued with the work item - and we can't just deallocate the 780 * call because the work item may be queued again. 781 */ 782 call->async_work.func = afs_delete_async_call; 783 if (!queue_work(afs_async_calls, &call->async_work)) 784 afs_put_call(call); 785 } 786 787 afs_put_call(call); 788 _leave(""); 789 } 790 791 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) 792 { 793 struct afs_call *call = (struct afs_call *)user_call_ID; 794 795 call->rxcall = rxcall; 796 } 797 798 /* 799 * Charge the incoming call preallocation. 800 */ 801 void afs_charge_preallocation(struct work_struct *work) 802 { 803 struct afs_net *net = 804 container_of(work, struct afs_net, charge_preallocation_work); 805 struct afs_call *call = net->spare_incoming_call; 806 807 for (;;) { 808 if (!call) { 809 call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL); 810 if (!call) 811 break; 812 813 call->async = true; 814 call->state = AFS_CALL_SV_AWAIT_OP_ID; 815 init_waitqueue_head(&call->waitq); 816 afs_extract_to_tmp(call); 817 } 818 819 if (rxrpc_kernel_charge_accept(net->socket, 820 afs_wake_up_async_call, 821 afs_rx_attach, 822 (unsigned long)call, 823 GFP_KERNEL, 824 call->debug_id) < 0) 825 break; 826 call = NULL; 827 } 828 net->spare_incoming_call = call; 829 } 830 831 /* 832 * Discard a preallocated call when a socket is shut down. 833 */ 834 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, 835 unsigned long user_call_ID) 836 { 837 struct afs_call *call = (struct afs_call *)user_call_ID; 838 839 call->rxcall = NULL; 840 afs_put_call(call); 841 } 842 843 /* 844 * Notification of an incoming call. 845 */ 846 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, 847 unsigned long user_call_ID) 848 { 849 struct afs_net *net = afs_sock2net(sk); 850 851 queue_work(afs_wq, &net->charge_preallocation_work); 852 } 853 854 /* 855 * Grab the operation ID from an incoming cache manager call. The socket 856 * buffer is discarded on error or if we don't yet have sufficient data. 857 */ 858 static int afs_deliver_cm_op_id(struct afs_call *call) 859 { 860 int ret; 861 862 _enter("{%zu}", iov_iter_count(call->_iter)); 863 864 /* the operation ID forms the first four bytes of the request data */ 865 ret = afs_extract_data(call, true); 866 if (ret < 0) 867 return ret; 868 869 call->operation_ID = ntohl(call->tmp); 870 afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST); 871 872 /* ask the cache manager to route the call (it'll change the call type 873 * if successful) */ 874 if (!afs_cm_incoming_call(call)) 875 return -ENOTSUPP; 876 877 trace_afs_cb_call(call); 878 879 /* pass responsibility for the remainer of this message off to the 880 * cache manager op */ 881 return call->type->deliver(call); 882 } 883 884 /* 885 * Advance the AFS call state when an RxRPC service call ends the transmit 886 * phase. 887 */ 888 static void afs_notify_end_reply_tx(struct sock *sock, 889 struct rxrpc_call *rxcall, 890 unsigned long call_user_ID) 891 { 892 struct afs_call *call = (struct afs_call *)call_user_ID; 893 894 afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK); 895 } 896 897 /* 898 * send an empty reply 899 */ 900 void afs_send_empty_reply(struct afs_call *call) 901 { 902 struct afs_net *net = call->net; 903 struct msghdr msg; 904 905 _enter(""); 906 907 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0); 908 909 msg.msg_name = NULL; 910 msg.msg_namelen = 0; 911 iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0); 912 msg.msg_control = NULL; 913 msg.msg_controllen = 0; 914 msg.msg_flags = 0; 915 916 switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0, 917 afs_notify_end_reply_tx)) { 918 case 0: 919 _leave(" [replied]"); 920 return; 921 922 case -ENOMEM: 923 _debug("oom"); 924 rxrpc_kernel_abort_call(net->socket, call->rxcall, 925 RX_USER_ABORT, -ENOMEM, "KOO"); 926 default: 927 _leave(" [error]"); 928 return; 929 } 930 } 931 932 /* 933 * send a simple reply 934 */ 935 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) 936 { 937 struct afs_net *net = call->net; 938 struct msghdr msg; 939 struct kvec iov[1]; 940 int n; 941 942 _enter(""); 943 944 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len); 945 946 iov[0].iov_base = (void *) buf; 947 iov[0].iov_len = len; 948 msg.msg_name = NULL; 949 msg.msg_namelen = 0; 950 iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len); 951 msg.msg_control = NULL; 952 msg.msg_controllen = 0; 953 msg.msg_flags = 0; 954 955 n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len, 956 afs_notify_end_reply_tx); 957 if (n >= 0) { 958 /* Success */ 959 _leave(" [replied]"); 960 return; 961 } 962 963 if (n == -ENOMEM) { 964 _debug("oom"); 965 rxrpc_kernel_abort_call(net->socket, call->rxcall, 966 RX_USER_ABORT, -ENOMEM, "KOO"); 967 } 968 _leave(" [error]"); 969 } 970 971 /* 972 * Extract a piece of data from the received data socket buffers. 973 */ 974 int afs_extract_data(struct afs_call *call, bool want_more) 975 { 976 struct afs_net *net = call->net; 977 struct iov_iter *iter = call->_iter; 978 enum afs_call_state state; 979 u32 remote_abort = 0; 980 int ret; 981 982 _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more); 983 984 ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter, 985 want_more, &remote_abort, 986 &call->service_id); 987 if (ret == 0 || ret == -EAGAIN) 988 return ret; 989 990 state = READ_ONCE(call->state); 991 if (ret == 1) { 992 switch (state) { 993 case AFS_CALL_CL_AWAIT_REPLY: 994 afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY); 995 break; 996 case AFS_CALL_SV_AWAIT_REQUEST: 997 afs_set_call_state(call, state, AFS_CALL_SV_REPLYING); 998 break; 999 case AFS_CALL_COMPLETE: 1000 kdebug("prem complete %d", call->error); 1001 return afs_io_error(call, afs_io_error_extract); 1002 default: 1003 break; 1004 } 1005 return 0; 1006 } 1007 1008 afs_set_call_complete(call, ret, remote_abort); 1009 return ret; 1010 } 1011 1012 /* 1013 * Log protocol error production. 1014 */ 1015 noinline int afs_protocol_error(struct afs_call *call, int error, 1016 enum afs_eproto_cause cause) 1017 { 1018 trace_afs_protocol_error(call, error, cause); 1019 return error; 1020 } 1021