1 /* 2 * QEMU Block driver for NBD 3 * 4 * Copyright (c) 2019 Virtuozzo International GmbH. 5 * Copyright (C) 2016 Red Hat, Inc. 6 * Copyright (C) 2008 Bull S.A.S. 7 * Author: Laurent Vivier <Laurent.Vivier@bull.net> 8 * 9 * Some parts: 10 * Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws> 11 * 12 * Permission is hereby granted, free of charge, to any person obtaining a copy 13 * of this software and associated documentation files (the "Software"), to deal 14 * in the Software without restriction, including without limitation the rights 15 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 16 * copies of the Software, and to permit persons to whom the Software is 17 * furnished to do so, subject to the following conditions: 18 * 19 * The above copyright notice and this permission notice shall be included in 20 * all copies or substantial portions of the Software. 21 * 22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 25 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 26 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 27 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 28 * THE SOFTWARE. 29 */ 30 31 #include "qemu/osdep.h" 32 33 #include "trace.h" 34 #include "qemu/uri.h" 35 #include "qemu/option.h" 36 #include "qemu/cutils.h" 37 #include "qemu/main-loop.h" 38 39 #include "qapi/qapi-visit-sockets.h" 40 #include "qapi/qmp/qstring.h" 41 #include "qapi/clone-visitor.h" 42 43 #include "block/qdict.h" 44 #include "block/nbd.h" 45 #include "block/block_int.h" 46 #include "block/coroutines.h" 47 48 #include "qemu/yank.h" 49 50 #define EN_OPTSTR ":exportname=" 51 #define MAX_NBD_REQUESTS 16 52 53 #define HANDLE_TO_INDEX(bs, handle) ((handle) ^ (uint64_t)(intptr_t)(bs)) 54 #define INDEX_TO_HANDLE(bs, index) ((index) ^ (uint64_t)(intptr_t)(bs)) 55 56 typedef struct { 57 Coroutine *coroutine; 58 uint64_t offset; /* original offset of the request */ 59 bool receiving; /* sleeping in the yield in nbd_receive_replies */ 60 } NBDClientRequest; 61 62 typedef enum NBDClientState { 63 NBD_CLIENT_CONNECTING_WAIT, 64 NBD_CLIENT_CONNECTING_NOWAIT, 65 NBD_CLIENT_CONNECTED, 66 NBD_CLIENT_QUIT 67 } NBDClientState; 68 69 typedef struct BDRVNBDState { 70 QIOChannel *ioc; /* The current I/O channel */ 71 NBDExportInfo info; 72 73 /* 74 * Protects state, free_sema, in_flight, requests[].coroutine, 75 * reconnect_delay_timer. 76 */ 77 QemuMutex requests_lock; 78 NBDClientState state; 79 CoQueue free_sema; 80 int in_flight; 81 NBDClientRequest requests[MAX_NBD_REQUESTS]; 82 QEMUTimer *reconnect_delay_timer; 83 84 /* Protects sending data on the socket. */ 85 CoMutex send_mutex; 86 87 /* 88 * Protects receiving reply headers from the socket, as well as the 89 * fields reply and requests[].receiving 90 */ 91 CoMutex receive_mutex; 92 NBDReply reply; 93 94 QEMUTimer *open_timer; 95 96 BlockDriverState *bs; 97 98 /* Connection parameters */ 99 uint32_t reconnect_delay; 100 uint32_t open_timeout; 101 SocketAddress *saddr; 102 char *export; 103 char *tlscredsid; 104 QCryptoTLSCreds *tlscreds; 105 char *tlshostname; 106 char *x_dirty_bitmap; 107 bool alloc_depth; 108 109 NBDClientConnection *conn; 110 } BDRVNBDState; 111 112 static void nbd_yank(void *opaque); 113 114 static void nbd_clear_bdrvstate(BlockDriverState *bs) 115 { 116 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 117 118 nbd_client_connection_release(s->conn); 119 s->conn = NULL; 120 121 yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name)); 122 123 /* Must not leave timers behind that would access freed data */ 124 assert(!s->reconnect_delay_timer); 125 assert(!s->open_timer); 126 127 object_unref(OBJECT(s->tlscreds)); 128 qapi_free_SocketAddress(s->saddr); 129 s->saddr = NULL; 130 g_free(s->export); 131 s->export = NULL; 132 g_free(s->tlscredsid); 133 s->tlscredsid = NULL; 134 g_free(s->tlshostname); 135 s->tlshostname = NULL; 136 g_free(s->x_dirty_bitmap); 137 s->x_dirty_bitmap = NULL; 138 } 139 140 /* Called with s->receive_mutex taken. */ 141 static bool coroutine_fn nbd_recv_coroutine_wake_one(NBDClientRequest *req) 142 { 143 if (req->receiving) { 144 req->receiving = false; 145 aio_co_wake(req->coroutine); 146 return true; 147 } 148 149 return false; 150 } 151 152 static void coroutine_fn nbd_recv_coroutines_wake(BDRVNBDState *s) 153 { 154 int i; 155 156 QEMU_LOCK_GUARD(&s->receive_mutex); 157 for (i = 0; i < MAX_NBD_REQUESTS; i++) { 158 if (nbd_recv_coroutine_wake_one(&s->requests[i])) { 159 return; 160 } 161 } 162 } 163 164 /* Called with s->requests_lock held. */ 165 static void coroutine_fn nbd_channel_error_locked(BDRVNBDState *s, int ret) 166 { 167 if (s->state == NBD_CLIENT_CONNECTED) { 168 qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 169 } 170 171 if (ret == -EIO) { 172 if (s->state == NBD_CLIENT_CONNECTED) { 173 s->state = s->reconnect_delay ? NBD_CLIENT_CONNECTING_WAIT : 174 NBD_CLIENT_CONNECTING_NOWAIT; 175 } 176 } else { 177 s->state = NBD_CLIENT_QUIT; 178 } 179 } 180 181 static void coroutine_fn nbd_channel_error(BDRVNBDState *s, int ret) 182 { 183 QEMU_LOCK_GUARD(&s->requests_lock); 184 nbd_channel_error_locked(s, ret); 185 } 186 187 static void reconnect_delay_timer_del(BDRVNBDState *s) 188 { 189 if (s->reconnect_delay_timer) { 190 timer_free(s->reconnect_delay_timer); 191 s->reconnect_delay_timer = NULL; 192 } 193 } 194 195 static void reconnect_delay_timer_cb(void *opaque) 196 { 197 BDRVNBDState *s = opaque; 198 199 reconnect_delay_timer_del(s); 200 WITH_QEMU_LOCK_GUARD(&s->requests_lock) { 201 if (s->state != NBD_CLIENT_CONNECTING_WAIT) { 202 return; 203 } 204 s->state = NBD_CLIENT_CONNECTING_NOWAIT; 205 } 206 nbd_co_establish_connection_cancel(s->conn); 207 } 208 209 static void reconnect_delay_timer_init(BDRVNBDState *s, uint64_t expire_time_ns) 210 { 211 assert(!s->reconnect_delay_timer); 212 s->reconnect_delay_timer = aio_timer_new(bdrv_get_aio_context(s->bs), 213 QEMU_CLOCK_REALTIME, 214 SCALE_NS, 215 reconnect_delay_timer_cb, s); 216 timer_mod(s->reconnect_delay_timer, expire_time_ns); 217 } 218 219 static void nbd_teardown_connection(BlockDriverState *bs) 220 { 221 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 222 223 assert(!s->in_flight); 224 225 if (s->ioc) { 226 qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 227 yank_unregister_function(BLOCKDEV_YANK_INSTANCE(s->bs->node_name), 228 nbd_yank, s->bs); 229 object_unref(OBJECT(s->ioc)); 230 s->ioc = NULL; 231 } 232 233 WITH_QEMU_LOCK_GUARD(&s->requests_lock) { 234 s->state = NBD_CLIENT_QUIT; 235 } 236 } 237 238 static void open_timer_del(BDRVNBDState *s) 239 { 240 if (s->open_timer) { 241 timer_free(s->open_timer); 242 s->open_timer = NULL; 243 } 244 } 245 246 static void open_timer_cb(void *opaque) 247 { 248 BDRVNBDState *s = opaque; 249 250 nbd_co_establish_connection_cancel(s->conn); 251 open_timer_del(s); 252 } 253 254 static void open_timer_init(BDRVNBDState *s, uint64_t expire_time_ns) 255 { 256 assert(!s->open_timer); 257 s->open_timer = aio_timer_new(bdrv_get_aio_context(s->bs), 258 QEMU_CLOCK_REALTIME, 259 SCALE_NS, 260 open_timer_cb, s); 261 timer_mod(s->open_timer, expire_time_ns); 262 } 263 264 static bool nbd_client_will_reconnect(BDRVNBDState *s) 265 { 266 /* 267 * Called only after a socket error, so this is not performance sensitive. 268 */ 269 QEMU_LOCK_GUARD(&s->requests_lock); 270 return s->state == NBD_CLIENT_CONNECTING_WAIT; 271 } 272 273 /* 274 * Update @bs with information learned during a completed negotiation process. 275 * Return failure if the server's advertised options are incompatible with the 276 * client's needs. 277 */ 278 static int nbd_handle_updated_info(BlockDriverState *bs, Error **errp) 279 { 280 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 281 int ret; 282 283 if (s->x_dirty_bitmap) { 284 if (!s->info.base_allocation) { 285 error_setg(errp, "requested x-dirty-bitmap %s not found", 286 s->x_dirty_bitmap); 287 return -EINVAL; 288 } 289 if (strcmp(s->x_dirty_bitmap, "qemu:allocation-depth") == 0) { 290 s->alloc_depth = true; 291 } 292 } 293 294 if (s->info.flags & NBD_FLAG_READ_ONLY) { 295 ret = bdrv_apply_auto_read_only(bs, "NBD export is read-only", errp); 296 if (ret < 0) { 297 return ret; 298 } 299 } 300 301 if (s->info.flags & NBD_FLAG_SEND_FUA) { 302 bs->supported_write_flags = BDRV_REQ_FUA; 303 bs->supported_zero_flags |= BDRV_REQ_FUA; 304 } 305 306 if (s->info.flags & NBD_FLAG_SEND_WRITE_ZEROES) { 307 bs->supported_zero_flags |= BDRV_REQ_MAY_UNMAP; 308 if (s->info.flags & NBD_FLAG_SEND_FAST_ZERO) { 309 bs->supported_zero_flags |= BDRV_REQ_NO_FALLBACK; 310 } 311 } 312 313 trace_nbd_client_handshake_success(s->export); 314 315 return 0; 316 } 317 318 int coroutine_fn nbd_co_do_establish_connection(BlockDriverState *bs, 319 bool blocking, Error **errp) 320 { 321 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 322 int ret; 323 IO_CODE(); 324 325 assert(!s->ioc); 326 327 s->ioc = nbd_co_establish_connection(s->conn, &s->info, blocking, errp); 328 if (!s->ioc) { 329 return -ECONNREFUSED; 330 } 331 332 yank_register_function(BLOCKDEV_YANK_INSTANCE(s->bs->node_name), nbd_yank, 333 bs); 334 335 ret = nbd_handle_updated_info(s->bs, NULL); 336 if (ret < 0) { 337 /* 338 * We have connected, but must fail for other reasons. 339 * Send NBD_CMD_DISC as a courtesy to the server. 340 */ 341 NBDRequest request = { .type = NBD_CMD_DISC }; 342 343 nbd_send_request(s->ioc, &request); 344 345 yank_unregister_function(BLOCKDEV_YANK_INSTANCE(s->bs->node_name), 346 nbd_yank, bs); 347 object_unref(OBJECT(s->ioc)); 348 s->ioc = NULL; 349 350 return ret; 351 } 352 353 qio_channel_set_blocking(s->ioc, false, NULL); 354 qio_channel_attach_aio_context(s->ioc, bdrv_get_aio_context(bs)); 355 356 /* successfully connected */ 357 WITH_QEMU_LOCK_GUARD(&s->requests_lock) { 358 s->state = NBD_CLIENT_CONNECTED; 359 } 360 361 return 0; 362 } 363 364 /* Called with s->requests_lock held. */ 365 static bool nbd_client_connecting(BDRVNBDState *s) 366 { 367 return s->state == NBD_CLIENT_CONNECTING_WAIT || 368 s->state == NBD_CLIENT_CONNECTING_NOWAIT; 369 } 370 371 /* Called with s->requests_lock taken. */ 372 static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) 373 { 374 bool blocking = s->state == NBD_CLIENT_CONNECTING_WAIT; 375 376 /* 377 * Now we are sure that nobody is accessing the channel, and no one will 378 * try until we set the state to CONNECTED. 379 */ 380 assert(nbd_client_connecting(s)); 381 assert(s->in_flight == 1); 382 383 if (blocking && !s->reconnect_delay_timer) { 384 /* 385 * It's the first reconnect attempt after switching to 386 * NBD_CLIENT_CONNECTING_WAIT 387 */ 388 g_assert(s->reconnect_delay); 389 reconnect_delay_timer_init(s, 390 qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + 391 s->reconnect_delay * NANOSECONDS_PER_SECOND); 392 } 393 394 /* Finalize previous connection if any */ 395 if (s->ioc) { 396 qio_channel_detach_aio_context(QIO_CHANNEL(s->ioc)); 397 yank_unregister_function(BLOCKDEV_YANK_INSTANCE(s->bs->node_name), 398 nbd_yank, s->bs); 399 object_unref(OBJECT(s->ioc)); 400 s->ioc = NULL; 401 } 402 403 qemu_mutex_unlock(&s->requests_lock); 404 nbd_co_do_establish_connection(s->bs, blocking, NULL); 405 qemu_mutex_lock(&s->requests_lock); 406 407 /* 408 * The reconnect attempt is done (maybe successfully, maybe not), so 409 * we no longer need this timer. Delete it so it will not outlive 410 * this I/O request (so draining removes all timers). 411 */ 412 reconnect_delay_timer_del(s); 413 } 414 415 static coroutine_fn int nbd_receive_replies(BDRVNBDState *s, uint64_t handle) 416 { 417 int ret; 418 uint64_t ind = HANDLE_TO_INDEX(s, handle), ind2; 419 QEMU_LOCK_GUARD(&s->receive_mutex); 420 421 while (true) { 422 if (s->reply.handle == handle) { 423 /* We are done */ 424 return 0; 425 } 426 427 if (s->reply.handle != 0) { 428 /* 429 * Some other request is being handled now. It should already be 430 * woken by whoever set s->reply.handle (or never wait in this 431 * yield). So, we should not wake it here. 432 */ 433 ind2 = HANDLE_TO_INDEX(s, s->reply.handle); 434 assert(!s->requests[ind2].receiving); 435 436 s->requests[ind].receiving = true; 437 qemu_co_mutex_unlock(&s->receive_mutex); 438 439 qemu_coroutine_yield(); 440 /* 441 * We may be woken for 2 reasons: 442 * 1. From this function, executing in parallel coroutine, when our 443 * handle is received. 444 * 2. From nbd_co_receive_one_chunk(), when previous request is 445 * finished and s->reply.handle set to 0. 446 * Anyway, it's OK to lock the mutex and go to the next iteration. 447 */ 448 449 qemu_co_mutex_lock(&s->receive_mutex); 450 assert(!s->requests[ind].receiving); 451 continue; 452 } 453 454 /* We are under mutex and handle is 0. We have to do the dirty work. */ 455 assert(s->reply.handle == 0); 456 ret = nbd_receive_reply(s->bs, s->ioc, &s->reply, NULL); 457 if (ret <= 0) { 458 ret = ret ? ret : -EIO; 459 nbd_channel_error(s, ret); 460 return ret; 461 } 462 if (nbd_reply_is_structured(&s->reply) && !s->info.structured_reply) { 463 nbd_channel_error(s, -EINVAL); 464 return -EINVAL; 465 } 466 ind2 = HANDLE_TO_INDEX(s, s->reply.handle); 467 if (ind2 >= MAX_NBD_REQUESTS || !s->requests[ind2].coroutine) { 468 nbd_channel_error(s, -EINVAL); 469 return -EINVAL; 470 } 471 if (s->reply.handle == handle) { 472 /* We are done */ 473 return 0; 474 } 475 nbd_recv_coroutine_wake_one(&s->requests[ind2]); 476 } 477 } 478 479 static int coroutine_fn nbd_co_send_request(BlockDriverState *bs, 480 NBDRequest *request, 481 QEMUIOVector *qiov) 482 { 483 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 484 int rc, i = -1; 485 486 qemu_mutex_lock(&s->requests_lock); 487 while (s->in_flight == MAX_NBD_REQUESTS || 488 (s->state != NBD_CLIENT_CONNECTED && s->in_flight > 0)) { 489 qemu_co_queue_wait(&s->free_sema, &s->requests_lock); 490 } 491 492 s->in_flight++; 493 if (s->state != NBD_CLIENT_CONNECTED) { 494 if (nbd_client_connecting(s)) { 495 nbd_reconnect_attempt(s); 496 qemu_co_queue_restart_all(&s->free_sema); 497 } 498 if (s->state != NBD_CLIENT_CONNECTED) { 499 rc = -EIO; 500 goto err; 501 } 502 } 503 504 for (i = 0; i < MAX_NBD_REQUESTS; i++) { 505 if (s->requests[i].coroutine == NULL) { 506 break; 507 } 508 } 509 510 assert(i < MAX_NBD_REQUESTS); 511 s->requests[i].coroutine = qemu_coroutine_self(); 512 s->requests[i].offset = request->from; 513 s->requests[i].receiving = false; 514 qemu_mutex_unlock(&s->requests_lock); 515 516 qemu_co_mutex_lock(&s->send_mutex); 517 request->handle = INDEX_TO_HANDLE(s, i); 518 519 assert(s->ioc); 520 521 if (qiov) { 522 qio_channel_set_cork(s->ioc, true); 523 rc = nbd_send_request(s->ioc, request); 524 if (rc >= 0 && qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov, 525 NULL) < 0) { 526 rc = -EIO; 527 } 528 qio_channel_set_cork(s->ioc, false); 529 } else { 530 rc = nbd_send_request(s->ioc, request); 531 } 532 qemu_co_mutex_unlock(&s->send_mutex); 533 534 if (rc < 0) { 535 qemu_mutex_lock(&s->requests_lock); 536 err: 537 nbd_channel_error_locked(s, rc); 538 if (i != -1) { 539 s->requests[i].coroutine = NULL; 540 } 541 s->in_flight--; 542 qemu_co_queue_next(&s->free_sema); 543 qemu_mutex_unlock(&s->requests_lock); 544 } 545 return rc; 546 } 547 548 static inline uint16_t payload_advance16(uint8_t **payload) 549 { 550 *payload += 2; 551 return lduw_be_p(*payload - 2); 552 } 553 554 static inline uint32_t payload_advance32(uint8_t **payload) 555 { 556 *payload += 4; 557 return ldl_be_p(*payload - 4); 558 } 559 560 static inline uint64_t payload_advance64(uint8_t **payload) 561 { 562 *payload += 8; 563 return ldq_be_p(*payload - 8); 564 } 565 566 static int nbd_parse_offset_hole_payload(BDRVNBDState *s, 567 NBDStructuredReplyChunk *chunk, 568 uint8_t *payload, uint64_t orig_offset, 569 QEMUIOVector *qiov, Error **errp) 570 { 571 uint64_t offset; 572 uint32_t hole_size; 573 574 if (chunk->length != sizeof(offset) + sizeof(hole_size)) { 575 error_setg(errp, "Protocol error: invalid payload for " 576 "NBD_REPLY_TYPE_OFFSET_HOLE"); 577 return -EINVAL; 578 } 579 580 offset = payload_advance64(&payload); 581 hole_size = payload_advance32(&payload); 582 583 if (!hole_size || offset < orig_offset || hole_size > qiov->size || 584 offset > orig_offset + qiov->size - hole_size) { 585 error_setg(errp, "Protocol error: server sent chunk exceeding requested" 586 " region"); 587 return -EINVAL; 588 } 589 if (s->info.min_block && 590 !QEMU_IS_ALIGNED(hole_size, s->info.min_block)) { 591 trace_nbd_structured_read_compliance("hole"); 592 } 593 594 qemu_iovec_memset(qiov, offset - orig_offset, 0, hole_size); 595 596 return 0; 597 } 598 599 /* 600 * nbd_parse_blockstatus_payload 601 * Based on our request, we expect only one extent in reply, for the 602 * base:allocation context. 603 */ 604 static int nbd_parse_blockstatus_payload(BDRVNBDState *s, 605 NBDStructuredReplyChunk *chunk, 606 uint8_t *payload, uint64_t orig_length, 607 NBDExtent *extent, Error **errp) 608 { 609 uint32_t context_id; 610 611 /* The server succeeded, so it must have sent [at least] one extent */ 612 if (chunk->length < sizeof(context_id) + sizeof(*extent)) { 613 error_setg(errp, "Protocol error: invalid payload for " 614 "NBD_REPLY_TYPE_BLOCK_STATUS"); 615 return -EINVAL; 616 } 617 618 context_id = payload_advance32(&payload); 619 if (s->info.context_id != context_id) { 620 error_setg(errp, "Protocol error: unexpected context id %d for " 621 "NBD_REPLY_TYPE_BLOCK_STATUS, when negotiated context " 622 "id is %d", context_id, 623 s->info.context_id); 624 return -EINVAL; 625 } 626 627 extent->length = payload_advance32(&payload); 628 extent->flags = payload_advance32(&payload); 629 630 if (extent->length == 0) { 631 error_setg(errp, "Protocol error: server sent status chunk with " 632 "zero length"); 633 return -EINVAL; 634 } 635 636 /* 637 * A server sending unaligned block status is in violation of the 638 * protocol, but as qemu-nbd 3.1 is such a server (at least for 639 * POSIX files that are not a multiple of 512 bytes, since qemu 640 * rounds files up to 512-byte multiples but lseek(SEEK_HOLE) 641 * still sees an implicit hole beyond the real EOF), it's nicer to 642 * work around the misbehaving server. If the request included 643 * more than the final unaligned block, truncate it back to an 644 * aligned result; if the request was only the final block, round 645 * up to the full block and change the status to fully-allocated 646 * (always a safe status, even if it loses information). 647 */ 648 if (s->info.min_block && !QEMU_IS_ALIGNED(extent->length, 649 s->info.min_block)) { 650 trace_nbd_parse_blockstatus_compliance("extent length is unaligned"); 651 if (extent->length > s->info.min_block) { 652 extent->length = QEMU_ALIGN_DOWN(extent->length, 653 s->info.min_block); 654 } else { 655 extent->length = s->info.min_block; 656 extent->flags = 0; 657 } 658 } 659 660 /* 661 * We used NBD_CMD_FLAG_REQ_ONE, so the server should not have 662 * sent us any more than one extent, nor should it have included 663 * status beyond our request in that extent. However, it's easy 664 * enough to ignore the server's noncompliance without killing the 665 * connection; just ignore trailing extents, and clamp things to 666 * the length of our request. 667 */ 668 if (chunk->length > sizeof(context_id) + sizeof(*extent)) { 669 trace_nbd_parse_blockstatus_compliance("more than one extent"); 670 } 671 if (extent->length > orig_length) { 672 extent->length = orig_length; 673 trace_nbd_parse_blockstatus_compliance("extent length too large"); 674 } 675 676 /* 677 * HACK: if we are using x-dirty-bitmaps to access 678 * qemu:allocation-depth, treat all depths > 2 the same as 2, 679 * since nbd_client_co_block_status is only expecting the low two 680 * bits to be set. 681 */ 682 if (s->alloc_depth && extent->flags > 2) { 683 extent->flags = 2; 684 } 685 686 return 0; 687 } 688 689 /* 690 * nbd_parse_error_payload 691 * on success @errp contains message describing nbd error reply 692 */ 693 static int nbd_parse_error_payload(NBDStructuredReplyChunk *chunk, 694 uint8_t *payload, int *request_ret, 695 Error **errp) 696 { 697 uint32_t error; 698 uint16_t message_size; 699 700 assert(chunk->type & (1 << 15)); 701 702 if (chunk->length < sizeof(error) + sizeof(message_size)) { 703 error_setg(errp, 704 "Protocol error: invalid payload for structured error"); 705 return -EINVAL; 706 } 707 708 error = nbd_errno_to_system_errno(payload_advance32(&payload)); 709 if (error == 0) { 710 error_setg(errp, "Protocol error: server sent structured error chunk " 711 "with error = 0"); 712 return -EINVAL; 713 } 714 715 *request_ret = -error; 716 message_size = payload_advance16(&payload); 717 718 if (message_size > chunk->length - sizeof(error) - sizeof(message_size)) { 719 error_setg(errp, "Protocol error: server sent structured error chunk " 720 "with incorrect message size"); 721 return -EINVAL; 722 } 723 724 /* TODO: Add a trace point to mention the server complaint */ 725 726 /* TODO handle ERROR_OFFSET */ 727 728 return 0; 729 } 730 731 static int coroutine_fn 732 nbd_co_receive_offset_data_payload(BDRVNBDState *s, uint64_t orig_offset, 733 QEMUIOVector *qiov, Error **errp) 734 { 735 QEMUIOVector sub_qiov; 736 uint64_t offset; 737 size_t data_size; 738 int ret; 739 NBDStructuredReplyChunk *chunk = &s->reply.structured; 740 741 assert(nbd_reply_is_structured(&s->reply)); 742 743 /* The NBD spec requires at least one byte of payload */ 744 if (chunk->length <= sizeof(offset)) { 745 error_setg(errp, "Protocol error: invalid payload for " 746 "NBD_REPLY_TYPE_OFFSET_DATA"); 747 return -EINVAL; 748 } 749 750 if (nbd_read64(s->ioc, &offset, "OFFSET_DATA offset", errp) < 0) { 751 return -EIO; 752 } 753 754 data_size = chunk->length - sizeof(offset); 755 assert(data_size); 756 if (offset < orig_offset || data_size > qiov->size || 757 offset > orig_offset + qiov->size - data_size) { 758 error_setg(errp, "Protocol error: server sent chunk exceeding requested" 759 " region"); 760 return -EINVAL; 761 } 762 if (s->info.min_block && !QEMU_IS_ALIGNED(data_size, s->info.min_block)) { 763 trace_nbd_structured_read_compliance("data"); 764 } 765 766 qemu_iovec_init(&sub_qiov, qiov->niov); 767 qemu_iovec_concat(&sub_qiov, qiov, offset - orig_offset, data_size); 768 ret = qio_channel_readv_all(s->ioc, sub_qiov.iov, sub_qiov.niov, errp); 769 qemu_iovec_destroy(&sub_qiov); 770 771 return ret < 0 ? -EIO : 0; 772 } 773 774 #define NBD_MAX_MALLOC_PAYLOAD 1000 775 static coroutine_fn int nbd_co_receive_structured_payload( 776 BDRVNBDState *s, void **payload, Error **errp) 777 { 778 int ret; 779 uint32_t len; 780 781 assert(nbd_reply_is_structured(&s->reply)); 782 783 len = s->reply.structured.length; 784 785 if (len == 0) { 786 return 0; 787 } 788 789 if (payload == NULL) { 790 error_setg(errp, "Unexpected structured payload"); 791 return -EINVAL; 792 } 793 794 if (len > NBD_MAX_MALLOC_PAYLOAD) { 795 error_setg(errp, "Payload too large"); 796 return -EINVAL; 797 } 798 799 *payload = g_new(char, len); 800 ret = nbd_read(s->ioc, *payload, len, "structured payload", errp); 801 if (ret < 0) { 802 g_free(*payload); 803 *payload = NULL; 804 return ret; 805 } 806 807 return 0; 808 } 809 810 /* 811 * nbd_co_do_receive_one_chunk 812 * for simple reply: 813 * set request_ret to received reply error 814 * if qiov is not NULL: read payload to @qiov 815 * for structured reply chunk: 816 * if error chunk: read payload, set @request_ret, do not set @payload 817 * else if offset_data chunk: read payload data to @qiov, do not set @payload 818 * else: read payload to @payload 819 * 820 * If function fails, @errp contains corresponding error message, and the 821 * connection with the server is suspect. If it returns 0, then the 822 * transaction succeeded (although @request_ret may be a negative errno 823 * corresponding to the server's error reply), and errp is unchanged. 824 */ 825 static coroutine_fn int nbd_co_do_receive_one_chunk( 826 BDRVNBDState *s, uint64_t handle, bool only_structured, 827 int *request_ret, QEMUIOVector *qiov, void **payload, Error **errp) 828 { 829 int ret; 830 int i = HANDLE_TO_INDEX(s, handle); 831 void *local_payload = NULL; 832 NBDStructuredReplyChunk *chunk; 833 834 if (payload) { 835 *payload = NULL; 836 } 837 *request_ret = 0; 838 839 ret = nbd_receive_replies(s, handle); 840 if (ret < 0) { 841 error_setg(errp, "Connection closed"); 842 return -EIO; 843 } 844 assert(s->ioc); 845 846 assert(s->reply.handle == handle); 847 848 if (nbd_reply_is_simple(&s->reply)) { 849 if (only_structured) { 850 error_setg(errp, "Protocol error: simple reply when structured " 851 "reply chunk was expected"); 852 return -EINVAL; 853 } 854 855 *request_ret = -nbd_errno_to_system_errno(s->reply.simple.error); 856 if (*request_ret < 0 || !qiov) { 857 return 0; 858 } 859 860 return qio_channel_readv_all(s->ioc, qiov->iov, qiov->niov, 861 errp) < 0 ? -EIO : 0; 862 } 863 864 /* handle structured reply chunk */ 865 assert(s->info.structured_reply); 866 chunk = &s->reply.structured; 867 868 if (chunk->type == NBD_REPLY_TYPE_NONE) { 869 if (!(chunk->flags & NBD_REPLY_FLAG_DONE)) { 870 error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk without" 871 " NBD_REPLY_FLAG_DONE flag set"); 872 return -EINVAL; 873 } 874 if (chunk->length) { 875 error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk with" 876 " nonzero length"); 877 return -EINVAL; 878 } 879 return 0; 880 } 881 882 if (chunk->type == NBD_REPLY_TYPE_OFFSET_DATA) { 883 if (!qiov) { 884 error_setg(errp, "Unexpected NBD_REPLY_TYPE_OFFSET_DATA chunk"); 885 return -EINVAL; 886 } 887 888 return nbd_co_receive_offset_data_payload(s, s->requests[i].offset, 889 qiov, errp); 890 } 891 892 if (nbd_reply_type_is_error(chunk->type)) { 893 payload = &local_payload; 894 } 895 896 ret = nbd_co_receive_structured_payload(s, payload, errp); 897 if (ret < 0) { 898 return ret; 899 } 900 901 if (nbd_reply_type_is_error(chunk->type)) { 902 ret = nbd_parse_error_payload(chunk, local_payload, request_ret, errp); 903 g_free(local_payload); 904 return ret; 905 } 906 907 return 0; 908 } 909 910 /* 911 * nbd_co_receive_one_chunk 912 * Read reply, wake up connection_co and set s->quit if needed. 913 * Return value is a fatal error code or normal nbd reply error code 914 */ 915 static coroutine_fn int nbd_co_receive_one_chunk( 916 BDRVNBDState *s, uint64_t handle, bool only_structured, 917 int *request_ret, QEMUIOVector *qiov, NBDReply *reply, void **payload, 918 Error **errp) 919 { 920 int ret = nbd_co_do_receive_one_chunk(s, handle, only_structured, 921 request_ret, qiov, payload, errp); 922 923 if (ret < 0) { 924 memset(reply, 0, sizeof(*reply)); 925 nbd_channel_error(s, ret); 926 } else { 927 /* For assert at loop start in nbd_connection_entry */ 928 *reply = s->reply; 929 } 930 s->reply.handle = 0; 931 932 nbd_recv_coroutines_wake(s); 933 934 return ret; 935 } 936 937 typedef struct NBDReplyChunkIter { 938 int ret; 939 int request_ret; 940 Error *err; 941 bool done, only_structured; 942 } NBDReplyChunkIter; 943 944 static void nbd_iter_channel_error(NBDReplyChunkIter *iter, 945 int ret, Error **local_err) 946 { 947 assert(local_err && *local_err); 948 assert(ret < 0); 949 950 if (!iter->ret) { 951 iter->ret = ret; 952 error_propagate(&iter->err, *local_err); 953 } else { 954 error_free(*local_err); 955 } 956 957 *local_err = NULL; 958 } 959 960 static void nbd_iter_request_error(NBDReplyChunkIter *iter, int ret) 961 { 962 assert(ret < 0); 963 964 if (!iter->request_ret) { 965 iter->request_ret = ret; 966 } 967 } 968 969 /* 970 * NBD_FOREACH_REPLY_CHUNK 971 * The pointer stored in @payload requires g_free() to free it. 972 */ 973 #define NBD_FOREACH_REPLY_CHUNK(s, iter, handle, structured, \ 974 qiov, reply, payload) \ 975 for (iter = (NBDReplyChunkIter) { .only_structured = structured }; \ 976 nbd_reply_chunk_iter_receive(s, &iter, handle, qiov, reply, payload);) 977 978 /* 979 * nbd_reply_chunk_iter_receive 980 * The pointer stored in @payload requires g_free() to free it. 981 */ 982 static bool nbd_reply_chunk_iter_receive(BDRVNBDState *s, 983 NBDReplyChunkIter *iter, 984 uint64_t handle, 985 QEMUIOVector *qiov, NBDReply *reply, 986 void **payload) 987 { 988 int ret, request_ret; 989 NBDReply local_reply; 990 NBDStructuredReplyChunk *chunk; 991 Error *local_err = NULL; 992 993 if (iter->done) { 994 /* Previous iteration was last. */ 995 goto break_loop; 996 } 997 998 if (reply == NULL) { 999 reply = &local_reply; 1000 } 1001 1002 ret = nbd_co_receive_one_chunk(s, handle, iter->only_structured, 1003 &request_ret, qiov, reply, payload, 1004 &local_err); 1005 if (ret < 0) { 1006 nbd_iter_channel_error(iter, ret, &local_err); 1007 } else if (request_ret < 0) { 1008 nbd_iter_request_error(iter, request_ret); 1009 } 1010 1011 /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */ 1012 if (nbd_reply_is_simple(reply) || iter->ret < 0) { 1013 goto break_loop; 1014 } 1015 1016 chunk = &reply->structured; 1017 iter->only_structured = true; 1018 1019 if (chunk->type == NBD_REPLY_TYPE_NONE) { 1020 /* NBD_REPLY_FLAG_DONE is already checked in nbd_co_receive_one_chunk */ 1021 assert(chunk->flags & NBD_REPLY_FLAG_DONE); 1022 goto break_loop; 1023 } 1024 1025 if (chunk->flags & NBD_REPLY_FLAG_DONE) { 1026 /* This iteration is last. */ 1027 iter->done = true; 1028 } 1029 1030 /* Execute the loop body */ 1031 return true; 1032 1033 break_loop: 1034 qemu_mutex_lock(&s->requests_lock); 1035 s->requests[HANDLE_TO_INDEX(s, handle)].coroutine = NULL; 1036 s->in_flight--; 1037 qemu_co_queue_next(&s->free_sema); 1038 qemu_mutex_unlock(&s->requests_lock); 1039 1040 return false; 1041 } 1042 1043 static int coroutine_fn nbd_co_receive_return_code(BDRVNBDState *s, uint64_t handle, 1044 int *request_ret, Error **errp) 1045 { 1046 NBDReplyChunkIter iter; 1047 1048 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, NULL, NULL) { 1049 /* nbd_reply_chunk_iter_receive does all the work */ 1050 } 1051 1052 error_propagate(errp, iter.err); 1053 *request_ret = iter.request_ret; 1054 return iter.ret; 1055 } 1056 1057 static int coroutine_fn nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t handle, 1058 uint64_t offset, QEMUIOVector *qiov, 1059 int *request_ret, Error **errp) 1060 { 1061 NBDReplyChunkIter iter; 1062 NBDReply reply; 1063 void *payload = NULL; 1064 Error *local_err = NULL; 1065 1066 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, s->info.structured_reply, 1067 qiov, &reply, &payload) 1068 { 1069 int ret; 1070 NBDStructuredReplyChunk *chunk = &reply.structured; 1071 1072 assert(nbd_reply_is_structured(&reply)); 1073 1074 switch (chunk->type) { 1075 case NBD_REPLY_TYPE_OFFSET_DATA: 1076 /* 1077 * special cased in nbd_co_receive_one_chunk, data is already 1078 * in qiov 1079 */ 1080 break; 1081 case NBD_REPLY_TYPE_OFFSET_HOLE: 1082 ret = nbd_parse_offset_hole_payload(s, &reply.structured, payload, 1083 offset, qiov, &local_err); 1084 if (ret < 0) { 1085 nbd_channel_error(s, ret); 1086 nbd_iter_channel_error(&iter, ret, &local_err); 1087 } 1088 break; 1089 default: 1090 if (!nbd_reply_type_is_error(chunk->type)) { 1091 /* not allowed reply type */ 1092 nbd_channel_error(s, -EINVAL); 1093 error_setg(&local_err, 1094 "Unexpected reply type: %d (%s) for CMD_READ", 1095 chunk->type, nbd_reply_type_lookup(chunk->type)); 1096 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1097 } 1098 } 1099 1100 g_free(payload); 1101 payload = NULL; 1102 } 1103 1104 error_propagate(errp, iter.err); 1105 *request_ret = iter.request_ret; 1106 return iter.ret; 1107 } 1108 1109 static int coroutine_fn nbd_co_receive_blockstatus_reply(BDRVNBDState *s, 1110 uint64_t handle, uint64_t length, 1111 NBDExtent *extent, 1112 int *request_ret, Error **errp) 1113 { 1114 NBDReplyChunkIter iter; 1115 NBDReply reply; 1116 void *payload = NULL; 1117 Error *local_err = NULL; 1118 bool received = false; 1119 1120 assert(!extent->length); 1121 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, &reply, &payload) { 1122 int ret; 1123 NBDStructuredReplyChunk *chunk = &reply.structured; 1124 1125 assert(nbd_reply_is_structured(&reply)); 1126 1127 switch (chunk->type) { 1128 case NBD_REPLY_TYPE_BLOCK_STATUS: 1129 if (received) { 1130 nbd_channel_error(s, -EINVAL); 1131 error_setg(&local_err, "Several BLOCK_STATUS chunks in reply"); 1132 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1133 } 1134 received = true; 1135 1136 ret = nbd_parse_blockstatus_payload(s, &reply.structured, 1137 payload, length, extent, 1138 &local_err); 1139 if (ret < 0) { 1140 nbd_channel_error(s, ret); 1141 nbd_iter_channel_error(&iter, ret, &local_err); 1142 } 1143 break; 1144 default: 1145 if (!nbd_reply_type_is_error(chunk->type)) { 1146 nbd_channel_error(s, -EINVAL); 1147 error_setg(&local_err, 1148 "Unexpected reply type: %d (%s) " 1149 "for CMD_BLOCK_STATUS", 1150 chunk->type, nbd_reply_type_lookup(chunk->type)); 1151 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1152 } 1153 } 1154 1155 g_free(payload); 1156 payload = NULL; 1157 } 1158 1159 if (!extent->length && !iter.request_ret) { 1160 error_setg(&local_err, "Server did not reply with any status extents"); 1161 nbd_iter_channel_error(&iter, -EIO, &local_err); 1162 } 1163 1164 error_propagate(errp, iter.err); 1165 *request_ret = iter.request_ret; 1166 return iter.ret; 1167 } 1168 1169 static int coroutine_fn nbd_co_request(BlockDriverState *bs, NBDRequest *request, 1170 QEMUIOVector *write_qiov) 1171 { 1172 int ret, request_ret; 1173 Error *local_err = NULL; 1174 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1175 1176 assert(request->type != NBD_CMD_READ); 1177 if (write_qiov) { 1178 assert(request->type == NBD_CMD_WRITE); 1179 assert(request->len == iov_size(write_qiov->iov, write_qiov->niov)); 1180 } else { 1181 assert(request->type != NBD_CMD_WRITE); 1182 } 1183 1184 do { 1185 ret = nbd_co_send_request(bs, request, write_qiov); 1186 if (ret < 0) { 1187 continue; 1188 } 1189 1190 ret = nbd_co_receive_return_code(s, request->handle, 1191 &request_ret, &local_err); 1192 if (local_err) { 1193 trace_nbd_co_request_fail(request->from, request->len, 1194 request->handle, request->flags, 1195 request->type, 1196 nbd_cmd_lookup(request->type), 1197 ret, error_get_pretty(local_err)); 1198 error_free(local_err); 1199 local_err = NULL; 1200 } 1201 } while (ret < 0 && nbd_client_will_reconnect(s)); 1202 1203 return ret ? ret : request_ret; 1204 } 1205 1206 static int coroutine_fn nbd_client_co_preadv(BlockDriverState *bs, int64_t offset, 1207 int64_t bytes, QEMUIOVector *qiov, 1208 BdrvRequestFlags flags) 1209 { 1210 int ret, request_ret; 1211 Error *local_err = NULL; 1212 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1213 NBDRequest request = { 1214 .type = NBD_CMD_READ, 1215 .from = offset, 1216 .len = bytes, 1217 }; 1218 1219 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1220 assert(!flags); 1221 1222 if (!bytes) { 1223 return 0; 1224 } 1225 /* 1226 * Work around the fact that the block layer doesn't do 1227 * byte-accurate sizing yet - if the read exceeds the server's 1228 * advertised size because the block layer rounded size up, then 1229 * truncate the request to the server and tail-pad with zero. 1230 */ 1231 if (offset >= s->info.size) { 1232 assert(bytes < BDRV_SECTOR_SIZE); 1233 qemu_iovec_memset(qiov, 0, 0, bytes); 1234 return 0; 1235 } 1236 if (offset + bytes > s->info.size) { 1237 uint64_t slop = offset + bytes - s->info.size; 1238 1239 assert(slop < BDRV_SECTOR_SIZE); 1240 qemu_iovec_memset(qiov, bytes - slop, 0, slop); 1241 request.len -= slop; 1242 } 1243 1244 do { 1245 ret = nbd_co_send_request(bs, &request, NULL); 1246 if (ret < 0) { 1247 continue; 1248 } 1249 1250 ret = nbd_co_receive_cmdread_reply(s, request.handle, offset, qiov, 1251 &request_ret, &local_err); 1252 if (local_err) { 1253 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1254 request.flags, request.type, 1255 nbd_cmd_lookup(request.type), 1256 ret, error_get_pretty(local_err)); 1257 error_free(local_err); 1258 local_err = NULL; 1259 } 1260 } while (ret < 0 && nbd_client_will_reconnect(s)); 1261 1262 return ret ? ret : request_ret; 1263 } 1264 1265 static int coroutine_fn nbd_client_co_pwritev(BlockDriverState *bs, int64_t offset, 1266 int64_t bytes, QEMUIOVector *qiov, 1267 BdrvRequestFlags flags) 1268 { 1269 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1270 NBDRequest request = { 1271 .type = NBD_CMD_WRITE, 1272 .from = offset, 1273 .len = bytes, 1274 }; 1275 1276 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1277 if (flags & BDRV_REQ_FUA) { 1278 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1279 request.flags |= NBD_CMD_FLAG_FUA; 1280 } 1281 1282 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1283 1284 if (!bytes) { 1285 return 0; 1286 } 1287 return nbd_co_request(bs, &request, qiov); 1288 } 1289 1290 static int coroutine_fn nbd_client_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, 1291 int64_t bytes, BdrvRequestFlags flags) 1292 { 1293 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1294 NBDRequest request = { 1295 .type = NBD_CMD_WRITE_ZEROES, 1296 .from = offset, 1297 .len = bytes, /* .len is uint32_t actually */ 1298 }; 1299 1300 assert(bytes <= UINT32_MAX); /* rely on max_pwrite_zeroes */ 1301 1302 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1303 if (!(s->info.flags & NBD_FLAG_SEND_WRITE_ZEROES)) { 1304 return -ENOTSUP; 1305 } 1306 1307 if (flags & BDRV_REQ_FUA) { 1308 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1309 request.flags |= NBD_CMD_FLAG_FUA; 1310 } 1311 if (!(flags & BDRV_REQ_MAY_UNMAP)) { 1312 request.flags |= NBD_CMD_FLAG_NO_HOLE; 1313 } 1314 if (flags & BDRV_REQ_NO_FALLBACK) { 1315 assert(s->info.flags & NBD_FLAG_SEND_FAST_ZERO); 1316 request.flags |= NBD_CMD_FLAG_FAST_ZERO; 1317 } 1318 1319 if (!bytes) { 1320 return 0; 1321 } 1322 return nbd_co_request(bs, &request, NULL); 1323 } 1324 1325 static int coroutine_fn nbd_client_co_flush(BlockDriverState *bs) 1326 { 1327 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1328 NBDRequest request = { .type = NBD_CMD_FLUSH }; 1329 1330 if (!(s->info.flags & NBD_FLAG_SEND_FLUSH)) { 1331 return 0; 1332 } 1333 1334 request.from = 0; 1335 request.len = 0; 1336 1337 return nbd_co_request(bs, &request, NULL); 1338 } 1339 1340 static int coroutine_fn nbd_client_co_pdiscard(BlockDriverState *bs, int64_t offset, 1341 int64_t bytes) 1342 { 1343 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1344 NBDRequest request = { 1345 .type = NBD_CMD_TRIM, 1346 .from = offset, 1347 .len = bytes, /* len is uint32_t */ 1348 }; 1349 1350 assert(bytes <= UINT32_MAX); /* rely on max_pdiscard */ 1351 1352 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1353 if (!(s->info.flags & NBD_FLAG_SEND_TRIM) || !bytes) { 1354 return 0; 1355 } 1356 1357 return nbd_co_request(bs, &request, NULL); 1358 } 1359 1360 static int coroutine_fn nbd_client_co_block_status( 1361 BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes, 1362 int64_t *pnum, int64_t *map, BlockDriverState **file) 1363 { 1364 int ret, request_ret; 1365 NBDExtent extent = { 0 }; 1366 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1367 Error *local_err = NULL; 1368 1369 NBDRequest request = { 1370 .type = NBD_CMD_BLOCK_STATUS, 1371 .from = offset, 1372 .len = MIN(QEMU_ALIGN_DOWN(INT_MAX, bs->bl.request_alignment), 1373 MIN(bytes, s->info.size - offset)), 1374 .flags = NBD_CMD_FLAG_REQ_ONE, 1375 }; 1376 1377 if (!s->info.base_allocation) { 1378 *pnum = bytes; 1379 *map = offset; 1380 *file = bs; 1381 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1382 } 1383 1384 /* 1385 * Work around the fact that the block layer doesn't do 1386 * byte-accurate sizing yet - if the status request exceeds the 1387 * server's advertised size because the block layer rounded size 1388 * up, we truncated the request to the server (above), or are 1389 * called on just the hole. 1390 */ 1391 if (offset >= s->info.size) { 1392 *pnum = bytes; 1393 assert(bytes < BDRV_SECTOR_SIZE); 1394 /* Intentionally don't report offset_valid for the hole */ 1395 return BDRV_BLOCK_ZERO; 1396 } 1397 1398 if (s->info.min_block) { 1399 assert(QEMU_IS_ALIGNED(request.len, s->info.min_block)); 1400 } 1401 do { 1402 ret = nbd_co_send_request(bs, &request, NULL); 1403 if (ret < 0) { 1404 continue; 1405 } 1406 1407 ret = nbd_co_receive_blockstatus_reply(s, request.handle, bytes, 1408 &extent, &request_ret, 1409 &local_err); 1410 if (local_err) { 1411 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1412 request.flags, request.type, 1413 nbd_cmd_lookup(request.type), 1414 ret, error_get_pretty(local_err)); 1415 error_free(local_err); 1416 local_err = NULL; 1417 } 1418 } while (ret < 0 && nbd_client_will_reconnect(s)); 1419 1420 if (ret < 0 || request_ret < 0) { 1421 return ret ? ret : request_ret; 1422 } 1423 1424 assert(extent.length); 1425 *pnum = extent.length; 1426 *map = offset; 1427 *file = bs; 1428 return (extent.flags & NBD_STATE_HOLE ? 0 : BDRV_BLOCK_DATA) | 1429 (extent.flags & NBD_STATE_ZERO ? BDRV_BLOCK_ZERO : 0) | 1430 BDRV_BLOCK_OFFSET_VALID; 1431 } 1432 1433 static int nbd_client_reopen_prepare(BDRVReopenState *state, 1434 BlockReopenQueue *queue, Error **errp) 1435 { 1436 BDRVNBDState *s = (BDRVNBDState *)state->bs->opaque; 1437 1438 if ((state->flags & BDRV_O_RDWR) && (s->info.flags & NBD_FLAG_READ_ONLY)) { 1439 error_setg(errp, "Can't reopen read-only NBD mount as read/write"); 1440 return -EACCES; 1441 } 1442 return 0; 1443 } 1444 1445 static void nbd_yank(void *opaque) 1446 { 1447 BlockDriverState *bs = opaque; 1448 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1449 1450 QEMU_LOCK_GUARD(&s->requests_lock); 1451 qio_channel_shutdown(QIO_CHANNEL(s->ioc), QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 1452 s->state = NBD_CLIENT_QUIT; 1453 } 1454 1455 static void nbd_client_close(BlockDriverState *bs) 1456 { 1457 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1458 NBDRequest request = { .type = NBD_CMD_DISC }; 1459 1460 if (s->ioc) { 1461 nbd_send_request(s->ioc, &request); 1462 } 1463 1464 nbd_teardown_connection(bs); 1465 } 1466 1467 1468 /* 1469 * Parse nbd_open options 1470 */ 1471 1472 static int nbd_parse_uri(const char *filename, QDict *options) 1473 { 1474 URI *uri; 1475 const char *p; 1476 QueryParams *qp = NULL; 1477 int ret = 0; 1478 bool is_unix; 1479 1480 uri = uri_parse(filename); 1481 if (!uri) { 1482 return -EINVAL; 1483 } 1484 1485 /* transport */ 1486 if (!g_strcmp0(uri->scheme, "nbd")) { 1487 is_unix = false; 1488 } else if (!g_strcmp0(uri->scheme, "nbd+tcp")) { 1489 is_unix = false; 1490 } else if (!g_strcmp0(uri->scheme, "nbd+unix")) { 1491 is_unix = true; 1492 } else { 1493 ret = -EINVAL; 1494 goto out; 1495 } 1496 1497 p = uri->path ? uri->path : ""; 1498 if (p[0] == '/') { 1499 p++; 1500 } 1501 if (p[0]) { 1502 qdict_put_str(options, "export", p); 1503 } 1504 1505 qp = query_params_parse(uri->query); 1506 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 1507 ret = -EINVAL; 1508 goto out; 1509 } 1510 1511 if (is_unix) { 1512 /* nbd+unix:///export?socket=path */ 1513 if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { 1514 ret = -EINVAL; 1515 goto out; 1516 } 1517 qdict_put_str(options, "server.type", "unix"); 1518 qdict_put_str(options, "server.path", qp->p[0].value); 1519 } else { 1520 QString *host; 1521 char *port_str; 1522 1523 /* nbd[+tcp]://host[:port]/export */ 1524 if (!uri->server) { 1525 ret = -EINVAL; 1526 goto out; 1527 } 1528 1529 /* strip braces from literal IPv6 address */ 1530 if (uri->server[0] == '[') { 1531 host = qstring_from_substr(uri->server, 1, 1532 strlen(uri->server) - 1); 1533 } else { 1534 host = qstring_from_str(uri->server); 1535 } 1536 1537 qdict_put_str(options, "server.type", "inet"); 1538 qdict_put(options, "server.host", host); 1539 1540 port_str = g_strdup_printf("%d", uri->port ?: NBD_DEFAULT_PORT); 1541 qdict_put_str(options, "server.port", port_str); 1542 g_free(port_str); 1543 } 1544 1545 out: 1546 if (qp) { 1547 query_params_free(qp); 1548 } 1549 uri_free(uri); 1550 return ret; 1551 } 1552 1553 static bool nbd_has_filename_options_conflict(QDict *options, Error **errp) 1554 { 1555 const QDictEntry *e; 1556 1557 for (e = qdict_first(options); e; e = qdict_next(options, e)) { 1558 if (!strcmp(e->key, "host") || 1559 !strcmp(e->key, "port") || 1560 !strcmp(e->key, "path") || 1561 !strcmp(e->key, "export") || 1562 strstart(e->key, "server.", NULL)) 1563 { 1564 error_setg(errp, "Option '%s' cannot be used with a file name", 1565 e->key); 1566 return true; 1567 } 1568 } 1569 1570 return false; 1571 } 1572 1573 static void nbd_parse_filename(const char *filename, QDict *options, 1574 Error **errp) 1575 { 1576 g_autofree char *file = NULL; 1577 char *export_name; 1578 const char *host_spec; 1579 const char *unixpath; 1580 1581 if (nbd_has_filename_options_conflict(options, errp)) { 1582 return; 1583 } 1584 1585 if (strstr(filename, "://")) { 1586 int ret = nbd_parse_uri(filename, options); 1587 if (ret < 0) { 1588 error_setg(errp, "No valid URL specified"); 1589 } 1590 return; 1591 } 1592 1593 file = g_strdup(filename); 1594 1595 export_name = strstr(file, EN_OPTSTR); 1596 if (export_name) { 1597 if (export_name[strlen(EN_OPTSTR)] == 0) { 1598 return; 1599 } 1600 export_name[0] = 0; /* truncate 'file' */ 1601 export_name += strlen(EN_OPTSTR); 1602 1603 qdict_put_str(options, "export", export_name); 1604 } 1605 1606 /* extract the host_spec - fail if it's not nbd:... */ 1607 if (!strstart(file, "nbd:", &host_spec)) { 1608 error_setg(errp, "File name string for NBD must start with 'nbd:'"); 1609 return; 1610 } 1611 1612 if (!*host_spec) { 1613 return; 1614 } 1615 1616 /* are we a UNIX or TCP socket? */ 1617 if (strstart(host_spec, "unix:", &unixpath)) { 1618 qdict_put_str(options, "server.type", "unix"); 1619 qdict_put_str(options, "server.path", unixpath); 1620 } else { 1621 InetSocketAddress *addr = g_new(InetSocketAddress, 1); 1622 1623 if (inet_parse(addr, host_spec, errp)) { 1624 goto out_inet; 1625 } 1626 1627 qdict_put_str(options, "server.type", "inet"); 1628 qdict_put_str(options, "server.host", addr->host); 1629 qdict_put_str(options, "server.port", addr->port); 1630 out_inet: 1631 qapi_free_InetSocketAddress(addr); 1632 } 1633 } 1634 1635 static bool nbd_process_legacy_socket_options(QDict *output_options, 1636 QemuOpts *legacy_opts, 1637 Error **errp) 1638 { 1639 const char *path = qemu_opt_get(legacy_opts, "path"); 1640 const char *host = qemu_opt_get(legacy_opts, "host"); 1641 const char *port = qemu_opt_get(legacy_opts, "port"); 1642 const QDictEntry *e; 1643 1644 if (!path && !host && !port) { 1645 return true; 1646 } 1647 1648 for (e = qdict_first(output_options); e; e = qdict_next(output_options, e)) 1649 { 1650 if (strstart(e->key, "server.", NULL)) { 1651 error_setg(errp, "Cannot use 'server' and path/host/port at the " 1652 "same time"); 1653 return false; 1654 } 1655 } 1656 1657 if (path && host) { 1658 error_setg(errp, "path and host may not be used at the same time"); 1659 return false; 1660 } else if (path) { 1661 if (port) { 1662 error_setg(errp, "port may not be used without host"); 1663 return false; 1664 } 1665 1666 qdict_put_str(output_options, "server.type", "unix"); 1667 qdict_put_str(output_options, "server.path", path); 1668 } else if (host) { 1669 qdict_put_str(output_options, "server.type", "inet"); 1670 qdict_put_str(output_options, "server.host", host); 1671 qdict_put_str(output_options, "server.port", 1672 port ?: stringify(NBD_DEFAULT_PORT)); 1673 } 1674 1675 return true; 1676 } 1677 1678 static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, 1679 Error **errp) 1680 { 1681 SocketAddress *saddr = NULL; 1682 QDict *addr = NULL; 1683 Visitor *iv = NULL; 1684 1685 qdict_extract_subqdict(options, &addr, "server."); 1686 if (!qdict_size(addr)) { 1687 error_setg(errp, "NBD server address missing"); 1688 goto done; 1689 } 1690 1691 iv = qobject_input_visitor_new_flat_confused(addr, errp); 1692 if (!iv) { 1693 goto done; 1694 } 1695 1696 if (!visit_type_SocketAddress(iv, NULL, &saddr, errp)) { 1697 goto done; 1698 } 1699 1700 if (socket_address_parse_named_fd(saddr, errp) < 0) { 1701 qapi_free_SocketAddress(saddr); 1702 saddr = NULL; 1703 goto done; 1704 } 1705 1706 done: 1707 qobject_unref(addr); 1708 visit_free(iv); 1709 return saddr; 1710 } 1711 1712 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 1713 { 1714 Object *obj; 1715 QCryptoTLSCreds *creds; 1716 1717 obj = object_resolve_path_component( 1718 object_get_objects_root(), id); 1719 if (!obj) { 1720 error_setg(errp, "No TLS credentials with id '%s'", 1721 id); 1722 return NULL; 1723 } 1724 creds = (QCryptoTLSCreds *) 1725 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 1726 if (!creds) { 1727 error_setg(errp, "Object with id '%s' is not TLS credentials", 1728 id); 1729 return NULL; 1730 } 1731 1732 if (!qcrypto_tls_creds_check_endpoint(creds, 1733 QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT, 1734 errp)) { 1735 return NULL; 1736 } 1737 object_ref(obj); 1738 return creds; 1739 } 1740 1741 1742 static QemuOptsList nbd_runtime_opts = { 1743 .name = "nbd", 1744 .head = QTAILQ_HEAD_INITIALIZER(nbd_runtime_opts.head), 1745 .desc = { 1746 { 1747 .name = "host", 1748 .type = QEMU_OPT_STRING, 1749 .help = "TCP host to connect to", 1750 }, 1751 { 1752 .name = "port", 1753 .type = QEMU_OPT_STRING, 1754 .help = "TCP port to connect to", 1755 }, 1756 { 1757 .name = "path", 1758 .type = QEMU_OPT_STRING, 1759 .help = "Unix socket path to connect to", 1760 }, 1761 { 1762 .name = "export", 1763 .type = QEMU_OPT_STRING, 1764 .help = "Name of the NBD export to open", 1765 }, 1766 { 1767 .name = "tls-creds", 1768 .type = QEMU_OPT_STRING, 1769 .help = "ID of the TLS credentials to use", 1770 }, 1771 { 1772 .name = "tls-hostname", 1773 .type = QEMU_OPT_STRING, 1774 .help = "Override hostname for validating TLS x509 certificate", 1775 }, 1776 { 1777 .name = "x-dirty-bitmap", 1778 .type = QEMU_OPT_STRING, 1779 .help = "experimental: expose named dirty bitmap in place of " 1780 "block status", 1781 }, 1782 { 1783 .name = "reconnect-delay", 1784 .type = QEMU_OPT_NUMBER, 1785 .help = "On an unexpected disconnect, the nbd client tries to " 1786 "connect again until succeeding or encountering a serious " 1787 "error. During the first @reconnect-delay seconds, all " 1788 "requests are paused and will be rerun on a successful " 1789 "reconnect. After that time, any delayed requests and all " 1790 "future requests before a successful reconnect will " 1791 "immediately fail. Default 0", 1792 }, 1793 { 1794 .name = "open-timeout", 1795 .type = QEMU_OPT_NUMBER, 1796 .help = "In seconds. If zero, the nbd driver tries the connection " 1797 "only once, and fails to open if the connection fails. " 1798 "If non-zero, the nbd driver will repeat connection " 1799 "attempts until successful or until @open-timeout seconds " 1800 "have elapsed. Default 0", 1801 }, 1802 { /* end of list */ } 1803 }, 1804 }; 1805 1806 static int nbd_process_options(BlockDriverState *bs, QDict *options, 1807 Error **errp) 1808 { 1809 BDRVNBDState *s = bs->opaque; 1810 QemuOpts *opts; 1811 int ret = -EINVAL; 1812 1813 opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort); 1814 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 1815 goto error; 1816 } 1817 1818 /* Translate @host, @port, and @path to a SocketAddress */ 1819 if (!nbd_process_legacy_socket_options(options, opts, errp)) { 1820 goto error; 1821 } 1822 1823 /* Pop the config into our state object. Exit if invalid. */ 1824 s->saddr = nbd_config(s, options, errp); 1825 if (!s->saddr) { 1826 goto error; 1827 } 1828 1829 s->export = g_strdup(qemu_opt_get(opts, "export")); 1830 if (s->export && strlen(s->export) > NBD_MAX_STRING_SIZE) { 1831 error_setg(errp, "export name too long to send to server"); 1832 goto error; 1833 } 1834 1835 s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds")); 1836 if (s->tlscredsid) { 1837 s->tlscreds = nbd_get_tls_creds(s->tlscredsid, errp); 1838 if (!s->tlscreds) { 1839 goto error; 1840 } 1841 1842 s->tlshostname = g_strdup(qemu_opt_get(opts, "tls-hostname")); 1843 if (!s->tlshostname && 1844 s->saddr->type == SOCKET_ADDRESS_TYPE_INET) { 1845 s->tlshostname = g_strdup(s->saddr->u.inet.host); 1846 } 1847 } 1848 1849 s->x_dirty_bitmap = g_strdup(qemu_opt_get(opts, "x-dirty-bitmap")); 1850 if (s->x_dirty_bitmap && strlen(s->x_dirty_bitmap) > NBD_MAX_STRING_SIZE) { 1851 error_setg(errp, "x-dirty-bitmap query too long to send to server"); 1852 goto error; 1853 } 1854 1855 s->reconnect_delay = qemu_opt_get_number(opts, "reconnect-delay", 0); 1856 s->open_timeout = qemu_opt_get_number(opts, "open-timeout", 0); 1857 1858 ret = 0; 1859 1860 error: 1861 qemu_opts_del(opts); 1862 return ret; 1863 } 1864 1865 static int nbd_open(BlockDriverState *bs, QDict *options, int flags, 1866 Error **errp) 1867 { 1868 int ret; 1869 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1870 1871 s->bs = bs; 1872 qemu_mutex_init(&s->requests_lock); 1873 qemu_co_queue_init(&s->free_sema); 1874 qemu_co_mutex_init(&s->send_mutex); 1875 qemu_co_mutex_init(&s->receive_mutex); 1876 1877 if (!yank_register_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name), errp)) { 1878 return -EEXIST; 1879 } 1880 1881 ret = nbd_process_options(bs, options, errp); 1882 if (ret < 0) { 1883 goto fail; 1884 } 1885 1886 s->conn = nbd_client_connection_new(s->saddr, true, s->export, 1887 s->x_dirty_bitmap, s->tlscreds, 1888 s->tlshostname); 1889 1890 if (s->open_timeout) { 1891 nbd_client_connection_enable_retry(s->conn); 1892 open_timer_init(s, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + 1893 s->open_timeout * NANOSECONDS_PER_SECOND); 1894 } 1895 1896 s->state = NBD_CLIENT_CONNECTING_WAIT; 1897 ret = nbd_do_establish_connection(bs, true, errp); 1898 if (ret < 0) { 1899 goto fail; 1900 } 1901 1902 /* 1903 * The connect attempt is done, so we no longer need this timer. 1904 * Delete it, because we do not want it to be around when this node 1905 * is drained or closed. 1906 */ 1907 open_timer_del(s); 1908 1909 nbd_client_connection_enable_retry(s->conn); 1910 1911 return 0; 1912 1913 fail: 1914 open_timer_del(s); 1915 nbd_clear_bdrvstate(bs); 1916 return ret; 1917 } 1918 1919 static int coroutine_fn nbd_co_flush(BlockDriverState *bs) 1920 { 1921 return nbd_client_co_flush(bs); 1922 } 1923 1924 static void nbd_refresh_limits(BlockDriverState *bs, Error **errp) 1925 { 1926 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1927 uint32_t min = s->info.min_block; 1928 uint32_t max = MIN_NON_ZERO(NBD_MAX_BUFFER_SIZE, s->info.max_block); 1929 1930 /* 1931 * If the server did not advertise an alignment: 1932 * - a size that is not sector-aligned implies that an alignment 1933 * of 1 can be used to access those tail bytes 1934 * - advertisement of block status requires an alignment of 1, so 1935 * that we don't violate block layer constraints that block 1936 * status is always aligned (as we can't control whether the 1937 * server will report sub-sector extents, such as a hole at EOF 1938 * on an unaligned POSIX file) 1939 * - otherwise, assume the server is so old that we are safer avoiding 1940 * sub-sector requests 1941 */ 1942 if (!min) { 1943 min = (!QEMU_IS_ALIGNED(s->info.size, BDRV_SECTOR_SIZE) || 1944 s->info.base_allocation) ? 1 : BDRV_SECTOR_SIZE; 1945 } 1946 1947 bs->bl.request_alignment = min; 1948 bs->bl.max_pdiscard = QEMU_ALIGN_DOWN(INT_MAX, min); 1949 bs->bl.max_pwrite_zeroes = max; 1950 bs->bl.max_transfer = max; 1951 1952 if (s->info.opt_block && 1953 s->info.opt_block > bs->bl.opt_transfer) { 1954 bs->bl.opt_transfer = s->info.opt_block; 1955 } 1956 } 1957 1958 static void nbd_close(BlockDriverState *bs) 1959 { 1960 nbd_client_close(bs); 1961 nbd_clear_bdrvstate(bs); 1962 } 1963 1964 /* 1965 * NBD cannot truncate, but if the caller asks to truncate to the same size, or 1966 * to a smaller size with exact=false, there is no reason to fail the 1967 * operation. 1968 * 1969 * Preallocation mode is ignored since it does not seems useful to fail when 1970 * we never change anything. 1971 */ 1972 static int coroutine_fn nbd_co_truncate(BlockDriverState *bs, int64_t offset, 1973 bool exact, PreallocMode prealloc, 1974 BdrvRequestFlags flags, Error **errp) 1975 { 1976 BDRVNBDState *s = bs->opaque; 1977 1978 if (offset != s->info.size && exact) { 1979 error_setg(errp, "Cannot resize NBD nodes"); 1980 return -ENOTSUP; 1981 } 1982 1983 if (offset > s->info.size) { 1984 error_setg(errp, "Cannot grow NBD nodes"); 1985 return -EINVAL; 1986 } 1987 1988 return 0; 1989 } 1990 1991 static int64_t nbd_getlength(BlockDriverState *bs) 1992 { 1993 BDRVNBDState *s = bs->opaque; 1994 1995 return s->info.size; 1996 } 1997 1998 static void nbd_refresh_filename(BlockDriverState *bs) 1999 { 2000 BDRVNBDState *s = bs->opaque; 2001 const char *host = NULL, *port = NULL, *path = NULL; 2002 size_t len = 0; 2003 2004 if (s->saddr->type == SOCKET_ADDRESS_TYPE_INET) { 2005 const InetSocketAddress *inet = &s->saddr->u.inet; 2006 if (!inet->has_ipv4 && !inet->has_ipv6 && !inet->has_to) { 2007 host = inet->host; 2008 port = inet->port; 2009 } 2010 } else if (s->saddr->type == SOCKET_ADDRESS_TYPE_UNIX) { 2011 path = s->saddr->u.q_unix.path; 2012 } /* else can't represent as pseudo-filename */ 2013 2014 if (path && s->export) { 2015 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2016 "nbd+unix:///%s?socket=%s", s->export, path); 2017 } else if (path && !s->export) { 2018 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2019 "nbd+unix://?socket=%s", path); 2020 } else if (host && s->export) { 2021 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2022 "nbd://%s:%s/%s", host, port, s->export); 2023 } else if (host && !s->export) { 2024 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2025 "nbd://%s:%s", host, port); 2026 } 2027 if (len >= sizeof(bs->exact_filename)) { 2028 /* Name is too long to represent exactly, so leave it empty. */ 2029 bs->exact_filename[0] = '\0'; 2030 } 2031 } 2032 2033 static char *nbd_dirname(BlockDriverState *bs, Error **errp) 2034 { 2035 /* The generic bdrv_dirname() implementation is able to work out some 2036 * directory name for NBD nodes, but that would be wrong. So far there is no 2037 * specification for how "export paths" would work, so NBD does not have 2038 * directory names. */ 2039 error_setg(errp, "Cannot generate a base directory for NBD nodes"); 2040 return NULL; 2041 } 2042 2043 static const char *const nbd_strong_runtime_opts[] = { 2044 "path", 2045 "host", 2046 "port", 2047 "export", 2048 "tls-creds", 2049 "tls-hostname", 2050 "server.", 2051 2052 NULL 2053 }; 2054 2055 static void nbd_cancel_in_flight(BlockDriverState *bs) 2056 { 2057 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 2058 2059 reconnect_delay_timer_del(s); 2060 2061 qemu_mutex_lock(&s->requests_lock); 2062 if (s->state == NBD_CLIENT_CONNECTING_WAIT) { 2063 s->state = NBD_CLIENT_CONNECTING_NOWAIT; 2064 } 2065 qemu_mutex_unlock(&s->requests_lock); 2066 2067 nbd_co_establish_connection_cancel(s->conn); 2068 } 2069 2070 static void nbd_attach_aio_context(BlockDriverState *bs, 2071 AioContext *new_context) 2072 { 2073 BDRVNBDState *s = bs->opaque; 2074 2075 /* The open_timer is used only during nbd_open() */ 2076 assert(!s->open_timer); 2077 2078 /* 2079 * The reconnect_delay_timer is scheduled in I/O paths when the 2080 * connection is lost, to cancel the reconnection attempt after a 2081 * given time. Once this attempt is done (successfully or not), 2082 * nbd_reconnect_attempt() ensures the timer is deleted before the 2083 * respective I/O request is resumed. 2084 * Since the AioContext can only be changed when a node is drained, 2085 * the reconnect_delay_timer cannot be active here. 2086 */ 2087 assert(!s->reconnect_delay_timer); 2088 2089 if (s->ioc) { 2090 qio_channel_attach_aio_context(s->ioc, new_context); 2091 } 2092 } 2093 2094 static void nbd_detach_aio_context(BlockDriverState *bs) 2095 { 2096 BDRVNBDState *s = bs->opaque; 2097 2098 assert(!s->open_timer); 2099 assert(!s->reconnect_delay_timer); 2100 2101 if (s->ioc) { 2102 qio_channel_detach_aio_context(s->ioc); 2103 } 2104 } 2105 2106 static BlockDriver bdrv_nbd = { 2107 .format_name = "nbd", 2108 .protocol_name = "nbd", 2109 .instance_size = sizeof(BDRVNBDState), 2110 .bdrv_parse_filename = nbd_parse_filename, 2111 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2112 .create_opts = &bdrv_create_opts_simple, 2113 .bdrv_file_open = nbd_open, 2114 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2115 .bdrv_co_preadv = nbd_client_co_preadv, 2116 .bdrv_co_pwritev = nbd_client_co_pwritev, 2117 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2118 .bdrv_close = nbd_close, 2119 .bdrv_co_flush_to_os = nbd_co_flush, 2120 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2121 .bdrv_refresh_limits = nbd_refresh_limits, 2122 .bdrv_co_truncate = nbd_co_truncate, 2123 .bdrv_getlength = nbd_getlength, 2124 .bdrv_refresh_filename = nbd_refresh_filename, 2125 .bdrv_co_block_status = nbd_client_co_block_status, 2126 .bdrv_dirname = nbd_dirname, 2127 .strong_runtime_opts = nbd_strong_runtime_opts, 2128 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2129 2130 .bdrv_attach_aio_context = nbd_attach_aio_context, 2131 .bdrv_detach_aio_context = nbd_detach_aio_context, 2132 }; 2133 2134 static BlockDriver bdrv_nbd_tcp = { 2135 .format_name = "nbd", 2136 .protocol_name = "nbd+tcp", 2137 .instance_size = sizeof(BDRVNBDState), 2138 .bdrv_parse_filename = nbd_parse_filename, 2139 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2140 .create_opts = &bdrv_create_opts_simple, 2141 .bdrv_file_open = nbd_open, 2142 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2143 .bdrv_co_preadv = nbd_client_co_preadv, 2144 .bdrv_co_pwritev = nbd_client_co_pwritev, 2145 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2146 .bdrv_close = nbd_close, 2147 .bdrv_co_flush_to_os = nbd_co_flush, 2148 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2149 .bdrv_refresh_limits = nbd_refresh_limits, 2150 .bdrv_co_truncate = nbd_co_truncate, 2151 .bdrv_getlength = nbd_getlength, 2152 .bdrv_refresh_filename = nbd_refresh_filename, 2153 .bdrv_co_block_status = nbd_client_co_block_status, 2154 .bdrv_dirname = nbd_dirname, 2155 .strong_runtime_opts = nbd_strong_runtime_opts, 2156 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2157 2158 .bdrv_attach_aio_context = nbd_attach_aio_context, 2159 .bdrv_detach_aio_context = nbd_detach_aio_context, 2160 }; 2161 2162 static BlockDriver bdrv_nbd_unix = { 2163 .format_name = "nbd", 2164 .protocol_name = "nbd+unix", 2165 .instance_size = sizeof(BDRVNBDState), 2166 .bdrv_parse_filename = nbd_parse_filename, 2167 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2168 .create_opts = &bdrv_create_opts_simple, 2169 .bdrv_file_open = nbd_open, 2170 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2171 .bdrv_co_preadv = nbd_client_co_preadv, 2172 .bdrv_co_pwritev = nbd_client_co_pwritev, 2173 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2174 .bdrv_close = nbd_close, 2175 .bdrv_co_flush_to_os = nbd_co_flush, 2176 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2177 .bdrv_refresh_limits = nbd_refresh_limits, 2178 .bdrv_co_truncate = nbd_co_truncate, 2179 .bdrv_getlength = nbd_getlength, 2180 .bdrv_refresh_filename = nbd_refresh_filename, 2181 .bdrv_co_block_status = nbd_client_co_block_status, 2182 .bdrv_dirname = nbd_dirname, 2183 .strong_runtime_opts = nbd_strong_runtime_opts, 2184 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2185 2186 .bdrv_attach_aio_context = nbd_attach_aio_context, 2187 .bdrv_detach_aio_context = nbd_detach_aio_context, 2188 }; 2189 2190 static void bdrv_nbd_init(void) 2191 { 2192 bdrv_register(&bdrv_nbd); 2193 bdrv_register(&bdrv_nbd_tcp); 2194 bdrv_register(&bdrv_nbd_unix); 2195 } 2196 2197 block_init(bdrv_nbd_init); 2198