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