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