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) { 525 if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov, 526 NULL) < 0) { 527 rc = -EIO; 528 } 529 } else if (rc >= 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 handle, bool only_structured, 831 int *request_ret, QEMUIOVector *qiov, void **payload, Error **errp) 832 { 833 int ret; 834 int i = HANDLE_TO_INDEX(s, handle); 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, handle); 844 if (ret < 0) { 845 error_setg(errp, "Connection closed"); 846 return -EIO; 847 } 848 assert(s->ioc); 849 850 assert(s->reply.handle == handle); 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 handle, 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, handle, 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.handle = 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, handle, structured, \ 978 qiov, reply, payload) \ 979 for (iter = (NBDReplyChunkIter) { .only_structured = structured }; \ 980 nbd_reply_chunk_iter_receive(s, &iter, handle, 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 nbd_reply_chunk_iter_receive(BDRVNBDState *s, 987 NBDReplyChunkIter *iter, 988 uint64_t handle, 989 QEMUIOVector *qiov, NBDReply *reply, 990 void **payload) 991 { 992 int ret, request_ret; 993 NBDReply local_reply; 994 NBDStructuredReplyChunk *chunk; 995 Error *local_err = NULL; 996 997 if (iter->done) { 998 /* Previous iteration was last. */ 999 goto break_loop; 1000 } 1001 1002 if (reply == NULL) { 1003 reply = &local_reply; 1004 } 1005 1006 ret = nbd_co_receive_one_chunk(s, handle, iter->only_structured, 1007 &request_ret, qiov, reply, payload, 1008 &local_err); 1009 if (ret < 0) { 1010 nbd_iter_channel_error(iter, ret, &local_err); 1011 } else if (request_ret < 0) { 1012 nbd_iter_request_error(iter, request_ret); 1013 } 1014 1015 /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */ 1016 if (nbd_reply_is_simple(reply) || iter->ret < 0) { 1017 goto break_loop; 1018 } 1019 1020 chunk = &reply->structured; 1021 iter->only_structured = true; 1022 1023 if (chunk->type == NBD_REPLY_TYPE_NONE) { 1024 /* NBD_REPLY_FLAG_DONE is already checked in nbd_co_receive_one_chunk */ 1025 assert(chunk->flags & NBD_REPLY_FLAG_DONE); 1026 goto break_loop; 1027 } 1028 1029 if (chunk->flags & NBD_REPLY_FLAG_DONE) { 1030 /* This iteration is last. */ 1031 iter->done = true; 1032 } 1033 1034 /* Execute the loop body */ 1035 return true; 1036 1037 break_loop: 1038 qemu_mutex_lock(&s->requests_lock); 1039 s->requests[HANDLE_TO_INDEX(s, handle)].coroutine = NULL; 1040 s->in_flight--; 1041 qemu_co_queue_next(&s->free_sema); 1042 qemu_mutex_unlock(&s->requests_lock); 1043 1044 return false; 1045 } 1046 1047 static int coroutine_fn nbd_co_receive_return_code(BDRVNBDState *s, uint64_t handle, 1048 int *request_ret, Error **errp) 1049 { 1050 NBDReplyChunkIter iter; 1051 1052 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, NULL, NULL) { 1053 /* nbd_reply_chunk_iter_receive does all the work */ 1054 } 1055 1056 error_propagate(errp, iter.err); 1057 *request_ret = iter.request_ret; 1058 return iter.ret; 1059 } 1060 1061 static int coroutine_fn nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t handle, 1062 uint64_t offset, QEMUIOVector *qiov, 1063 int *request_ret, Error **errp) 1064 { 1065 NBDReplyChunkIter iter; 1066 NBDReply reply; 1067 void *payload = NULL; 1068 Error *local_err = NULL; 1069 1070 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, s->info.structured_reply, 1071 qiov, &reply, &payload) 1072 { 1073 int ret; 1074 NBDStructuredReplyChunk *chunk = &reply.structured; 1075 1076 assert(nbd_reply_is_structured(&reply)); 1077 1078 switch (chunk->type) { 1079 case NBD_REPLY_TYPE_OFFSET_DATA: 1080 /* 1081 * special cased in nbd_co_receive_one_chunk, data is already 1082 * in qiov 1083 */ 1084 break; 1085 case NBD_REPLY_TYPE_OFFSET_HOLE: 1086 ret = nbd_parse_offset_hole_payload(s, &reply.structured, payload, 1087 offset, qiov, &local_err); 1088 if (ret < 0) { 1089 nbd_channel_error(s, ret); 1090 nbd_iter_channel_error(&iter, ret, &local_err); 1091 } 1092 break; 1093 default: 1094 if (!nbd_reply_type_is_error(chunk->type)) { 1095 /* not allowed reply type */ 1096 nbd_channel_error(s, -EINVAL); 1097 error_setg(&local_err, 1098 "Unexpected reply type: %d (%s) for CMD_READ", 1099 chunk->type, nbd_reply_type_lookup(chunk->type)); 1100 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1101 } 1102 } 1103 1104 g_free(payload); 1105 payload = NULL; 1106 } 1107 1108 error_propagate(errp, iter.err); 1109 *request_ret = iter.request_ret; 1110 return iter.ret; 1111 } 1112 1113 static int coroutine_fn nbd_co_receive_blockstatus_reply(BDRVNBDState *s, 1114 uint64_t handle, uint64_t length, 1115 NBDExtent *extent, 1116 int *request_ret, Error **errp) 1117 { 1118 NBDReplyChunkIter iter; 1119 NBDReply reply; 1120 void *payload = NULL; 1121 Error *local_err = NULL; 1122 bool received = false; 1123 1124 assert(!extent->length); 1125 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, &reply, &payload) { 1126 int ret; 1127 NBDStructuredReplyChunk *chunk = &reply.structured; 1128 1129 assert(nbd_reply_is_structured(&reply)); 1130 1131 switch (chunk->type) { 1132 case NBD_REPLY_TYPE_BLOCK_STATUS: 1133 if (received) { 1134 nbd_channel_error(s, -EINVAL); 1135 error_setg(&local_err, "Several BLOCK_STATUS chunks in reply"); 1136 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1137 } 1138 received = true; 1139 1140 ret = nbd_parse_blockstatus_payload(s, &reply.structured, 1141 payload, length, extent, 1142 &local_err); 1143 if (ret < 0) { 1144 nbd_channel_error(s, ret); 1145 nbd_iter_channel_error(&iter, ret, &local_err); 1146 } 1147 break; 1148 default: 1149 if (!nbd_reply_type_is_error(chunk->type)) { 1150 nbd_channel_error(s, -EINVAL); 1151 error_setg(&local_err, 1152 "Unexpected reply type: %d (%s) " 1153 "for CMD_BLOCK_STATUS", 1154 chunk->type, nbd_reply_type_lookup(chunk->type)); 1155 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1156 } 1157 } 1158 1159 g_free(payload); 1160 payload = NULL; 1161 } 1162 1163 if (!extent->length && !iter.request_ret) { 1164 error_setg(&local_err, "Server did not reply with any status extents"); 1165 nbd_iter_channel_error(&iter, -EIO, &local_err); 1166 } 1167 1168 error_propagate(errp, iter.err); 1169 *request_ret = iter.request_ret; 1170 return iter.ret; 1171 } 1172 1173 static int coroutine_fn nbd_co_request(BlockDriverState *bs, NBDRequest *request, 1174 QEMUIOVector *write_qiov) 1175 { 1176 int ret, request_ret; 1177 Error *local_err = NULL; 1178 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1179 1180 assert(request->type != NBD_CMD_READ); 1181 if (write_qiov) { 1182 assert(request->type == NBD_CMD_WRITE); 1183 assert(request->len == iov_size(write_qiov->iov, write_qiov->niov)); 1184 } else { 1185 assert(request->type != NBD_CMD_WRITE); 1186 } 1187 1188 do { 1189 ret = nbd_co_send_request(bs, request, write_qiov); 1190 if (ret < 0) { 1191 continue; 1192 } 1193 1194 ret = nbd_co_receive_return_code(s, request->handle, 1195 &request_ret, &local_err); 1196 if (local_err) { 1197 trace_nbd_co_request_fail(request->from, request->len, 1198 request->handle, request->flags, 1199 request->type, 1200 nbd_cmd_lookup(request->type), 1201 ret, error_get_pretty(local_err)); 1202 error_free(local_err); 1203 local_err = NULL; 1204 } 1205 } while (ret < 0 && nbd_client_will_reconnect(s)); 1206 1207 return ret ? ret : request_ret; 1208 } 1209 1210 static int coroutine_fn nbd_client_co_preadv(BlockDriverState *bs, int64_t offset, 1211 int64_t bytes, QEMUIOVector *qiov, 1212 BdrvRequestFlags flags) 1213 { 1214 int ret, request_ret; 1215 Error *local_err = NULL; 1216 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1217 NBDRequest request = { 1218 .type = NBD_CMD_READ, 1219 .from = offset, 1220 .len = bytes, 1221 }; 1222 1223 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1224 assert(!flags); 1225 1226 if (!bytes) { 1227 return 0; 1228 } 1229 /* 1230 * Work around the fact that the block layer doesn't do 1231 * byte-accurate sizing yet - if the read exceeds the server's 1232 * advertised size because the block layer rounded size up, then 1233 * truncate the request to the server and tail-pad with zero. 1234 */ 1235 if (offset >= s->info.size) { 1236 assert(bytes < BDRV_SECTOR_SIZE); 1237 qemu_iovec_memset(qiov, 0, 0, bytes); 1238 return 0; 1239 } 1240 if (offset + bytes > s->info.size) { 1241 uint64_t slop = offset + bytes - s->info.size; 1242 1243 assert(slop < BDRV_SECTOR_SIZE); 1244 qemu_iovec_memset(qiov, bytes - slop, 0, slop); 1245 request.len -= slop; 1246 } 1247 1248 do { 1249 ret = nbd_co_send_request(bs, &request, NULL); 1250 if (ret < 0) { 1251 continue; 1252 } 1253 1254 ret = nbd_co_receive_cmdread_reply(s, request.handle, offset, qiov, 1255 &request_ret, &local_err); 1256 if (local_err) { 1257 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1258 request.flags, request.type, 1259 nbd_cmd_lookup(request.type), 1260 ret, error_get_pretty(local_err)); 1261 error_free(local_err); 1262 local_err = NULL; 1263 } 1264 } while (ret < 0 && nbd_client_will_reconnect(s)); 1265 1266 return ret ? ret : request_ret; 1267 } 1268 1269 static int coroutine_fn nbd_client_co_pwritev(BlockDriverState *bs, int64_t offset, 1270 int64_t bytes, QEMUIOVector *qiov, 1271 BdrvRequestFlags flags) 1272 { 1273 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1274 NBDRequest request = { 1275 .type = NBD_CMD_WRITE, 1276 .from = offset, 1277 .len = bytes, 1278 }; 1279 1280 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1281 if (flags & BDRV_REQ_FUA) { 1282 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1283 request.flags |= NBD_CMD_FLAG_FUA; 1284 } 1285 1286 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1287 1288 if (!bytes) { 1289 return 0; 1290 } 1291 return nbd_co_request(bs, &request, qiov); 1292 } 1293 1294 static int coroutine_fn nbd_client_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, 1295 int64_t bytes, BdrvRequestFlags flags) 1296 { 1297 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1298 NBDRequest request = { 1299 .type = NBD_CMD_WRITE_ZEROES, 1300 .from = offset, 1301 .len = bytes, /* .len is uint32_t actually */ 1302 }; 1303 1304 assert(bytes <= UINT32_MAX); /* rely on max_pwrite_zeroes */ 1305 1306 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1307 if (!(s->info.flags & NBD_FLAG_SEND_WRITE_ZEROES)) { 1308 return -ENOTSUP; 1309 } 1310 1311 if (flags & BDRV_REQ_FUA) { 1312 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1313 request.flags |= NBD_CMD_FLAG_FUA; 1314 } 1315 if (!(flags & BDRV_REQ_MAY_UNMAP)) { 1316 request.flags |= NBD_CMD_FLAG_NO_HOLE; 1317 } 1318 if (flags & BDRV_REQ_NO_FALLBACK) { 1319 assert(s->info.flags & NBD_FLAG_SEND_FAST_ZERO); 1320 request.flags |= NBD_CMD_FLAG_FAST_ZERO; 1321 } 1322 1323 if (!bytes) { 1324 return 0; 1325 } 1326 return nbd_co_request(bs, &request, NULL); 1327 } 1328 1329 static int coroutine_fn nbd_client_co_flush(BlockDriverState *bs) 1330 { 1331 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1332 NBDRequest request = { .type = NBD_CMD_FLUSH }; 1333 1334 if (!(s->info.flags & NBD_FLAG_SEND_FLUSH)) { 1335 return 0; 1336 } 1337 1338 request.from = 0; 1339 request.len = 0; 1340 1341 return nbd_co_request(bs, &request, NULL); 1342 } 1343 1344 static int coroutine_fn nbd_client_co_pdiscard(BlockDriverState *bs, int64_t offset, 1345 int64_t bytes) 1346 { 1347 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1348 NBDRequest request = { 1349 .type = NBD_CMD_TRIM, 1350 .from = offset, 1351 .len = bytes, /* len is uint32_t */ 1352 }; 1353 1354 assert(bytes <= UINT32_MAX); /* rely on max_pdiscard */ 1355 1356 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1357 if (!(s->info.flags & NBD_FLAG_SEND_TRIM) || !bytes) { 1358 return 0; 1359 } 1360 1361 return nbd_co_request(bs, &request, NULL); 1362 } 1363 1364 static int coroutine_fn nbd_client_co_block_status( 1365 BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes, 1366 int64_t *pnum, int64_t *map, BlockDriverState **file) 1367 { 1368 int ret, request_ret; 1369 NBDExtent extent = { 0 }; 1370 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1371 Error *local_err = NULL; 1372 1373 NBDRequest request = { 1374 .type = NBD_CMD_BLOCK_STATUS, 1375 .from = offset, 1376 .len = MIN(QEMU_ALIGN_DOWN(INT_MAX, bs->bl.request_alignment), 1377 MIN(bytes, s->info.size - offset)), 1378 .flags = NBD_CMD_FLAG_REQ_ONE, 1379 }; 1380 1381 if (!s->info.base_allocation) { 1382 *pnum = bytes; 1383 *map = offset; 1384 *file = bs; 1385 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1386 } 1387 1388 /* 1389 * Work around the fact that the block layer doesn't do 1390 * byte-accurate sizing yet - if the status request exceeds the 1391 * server's advertised size because the block layer rounded size 1392 * up, we truncated the request to the server (above), or are 1393 * called on just the hole. 1394 */ 1395 if (offset >= s->info.size) { 1396 *pnum = bytes; 1397 assert(bytes < BDRV_SECTOR_SIZE); 1398 /* Intentionally don't report offset_valid for the hole */ 1399 return BDRV_BLOCK_ZERO; 1400 } 1401 1402 if (s->info.min_block) { 1403 assert(QEMU_IS_ALIGNED(request.len, s->info.min_block)); 1404 } 1405 do { 1406 ret = nbd_co_send_request(bs, &request, NULL); 1407 if (ret < 0) { 1408 continue; 1409 } 1410 1411 ret = nbd_co_receive_blockstatus_reply(s, request.handle, bytes, 1412 &extent, &request_ret, 1413 &local_err); 1414 if (local_err) { 1415 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1416 request.flags, request.type, 1417 nbd_cmd_lookup(request.type), 1418 ret, error_get_pretty(local_err)); 1419 error_free(local_err); 1420 local_err = NULL; 1421 } 1422 } while (ret < 0 && nbd_client_will_reconnect(s)); 1423 1424 if (ret < 0 || request_ret < 0) { 1425 return ret ? ret : request_ret; 1426 } 1427 1428 assert(extent.length); 1429 *pnum = extent.length; 1430 *map = offset; 1431 *file = bs; 1432 return (extent.flags & NBD_STATE_HOLE ? 0 : BDRV_BLOCK_DATA) | 1433 (extent.flags & NBD_STATE_ZERO ? BDRV_BLOCK_ZERO : 0) | 1434 BDRV_BLOCK_OFFSET_VALID; 1435 } 1436 1437 static int nbd_client_reopen_prepare(BDRVReopenState *state, 1438 BlockReopenQueue *queue, Error **errp) 1439 { 1440 BDRVNBDState *s = (BDRVNBDState *)state->bs->opaque; 1441 1442 if ((state->flags & BDRV_O_RDWR) && (s->info.flags & NBD_FLAG_READ_ONLY)) { 1443 error_setg(errp, "Can't reopen read-only NBD mount as read/write"); 1444 return -EACCES; 1445 } 1446 return 0; 1447 } 1448 1449 static void nbd_yank(void *opaque) 1450 { 1451 BlockDriverState *bs = opaque; 1452 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1453 1454 QEMU_LOCK_GUARD(&s->requests_lock); 1455 qio_channel_shutdown(QIO_CHANNEL(s->ioc), QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 1456 s->state = NBD_CLIENT_QUIT; 1457 } 1458 1459 static void nbd_client_close(BlockDriverState *bs) 1460 { 1461 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1462 NBDRequest request = { .type = NBD_CMD_DISC }; 1463 1464 if (s->ioc) { 1465 nbd_send_request(s->ioc, &request); 1466 } 1467 1468 nbd_teardown_connection(bs); 1469 } 1470 1471 1472 /* 1473 * Parse nbd_open options 1474 */ 1475 1476 static int nbd_parse_uri(const char *filename, QDict *options) 1477 { 1478 URI *uri; 1479 const char *p; 1480 QueryParams *qp = NULL; 1481 int ret = 0; 1482 bool is_unix; 1483 1484 uri = uri_parse(filename); 1485 if (!uri) { 1486 return -EINVAL; 1487 } 1488 1489 /* transport */ 1490 if (!g_strcmp0(uri->scheme, "nbd")) { 1491 is_unix = false; 1492 } else if (!g_strcmp0(uri->scheme, "nbd+tcp")) { 1493 is_unix = false; 1494 } else if (!g_strcmp0(uri->scheme, "nbd+unix")) { 1495 is_unix = true; 1496 } else { 1497 ret = -EINVAL; 1498 goto out; 1499 } 1500 1501 p = uri->path ? uri->path : ""; 1502 if (p[0] == '/') { 1503 p++; 1504 } 1505 if (p[0]) { 1506 qdict_put_str(options, "export", p); 1507 } 1508 1509 qp = query_params_parse(uri->query); 1510 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 1511 ret = -EINVAL; 1512 goto out; 1513 } 1514 1515 if (is_unix) { 1516 /* nbd+unix:///export?socket=path */ 1517 if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { 1518 ret = -EINVAL; 1519 goto out; 1520 } 1521 qdict_put_str(options, "server.type", "unix"); 1522 qdict_put_str(options, "server.path", qp->p[0].value); 1523 } else { 1524 QString *host; 1525 char *port_str; 1526 1527 /* nbd[+tcp]://host[:port]/export */ 1528 if (!uri->server) { 1529 ret = -EINVAL; 1530 goto out; 1531 } 1532 1533 /* strip braces from literal IPv6 address */ 1534 if (uri->server[0] == '[') { 1535 host = qstring_from_substr(uri->server, 1, 1536 strlen(uri->server) - 1); 1537 } else { 1538 host = qstring_from_str(uri->server); 1539 } 1540 1541 qdict_put_str(options, "server.type", "inet"); 1542 qdict_put(options, "server.host", host); 1543 1544 port_str = g_strdup_printf("%d", uri->port ?: NBD_DEFAULT_PORT); 1545 qdict_put_str(options, "server.port", port_str); 1546 g_free(port_str); 1547 } 1548 1549 out: 1550 if (qp) { 1551 query_params_free(qp); 1552 } 1553 uri_free(uri); 1554 return ret; 1555 } 1556 1557 static bool nbd_has_filename_options_conflict(QDict *options, Error **errp) 1558 { 1559 const QDictEntry *e; 1560 1561 for (e = qdict_first(options); e; e = qdict_next(options, e)) { 1562 if (!strcmp(e->key, "host") || 1563 !strcmp(e->key, "port") || 1564 !strcmp(e->key, "path") || 1565 !strcmp(e->key, "export") || 1566 strstart(e->key, "server.", NULL)) 1567 { 1568 error_setg(errp, "Option '%s' cannot be used with a file name", 1569 e->key); 1570 return true; 1571 } 1572 } 1573 1574 return false; 1575 } 1576 1577 static void nbd_parse_filename(const char *filename, QDict *options, 1578 Error **errp) 1579 { 1580 g_autofree char *file = NULL; 1581 char *export_name; 1582 const char *host_spec; 1583 const char *unixpath; 1584 1585 if (nbd_has_filename_options_conflict(options, errp)) { 1586 return; 1587 } 1588 1589 if (strstr(filename, "://")) { 1590 int ret = nbd_parse_uri(filename, options); 1591 if (ret < 0) { 1592 error_setg(errp, "No valid URL specified"); 1593 } 1594 return; 1595 } 1596 1597 file = g_strdup(filename); 1598 1599 export_name = strstr(file, EN_OPTSTR); 1600 if (export_name) { 1601 if (export_name[strlen(EN_OPTSTR)] == 0) { 1602 return; 1603 } 1604 export_name[0] = 0; /* truncate 'file' */ 1605 export_name += strlen(EN_OPTSTR); 1606 1607 qdict_put_str(options, "export", export_name); 1608 } 1609 1610 /* extract the host_spec - fail if it's not nbd:... */ 1611 if (!strstart(file, "nbd:", &host_spec)) { 1612 error_setg(errp, "File name string for NBD must start with 'nbd:'"); 1613 return; 1614 } 1615 1616 if (!*host_spec) { 1617 return; 1618 } 1619 1620 /* are we a UNIX or TCP socket? */ 1621 if (strstart(host_spec, "unix:", &unixpath)) { 1622 qdict_put_str(options, "server.type", "unix"); 1623 qdict_put_str(options, "server.path", unixpath); 1624 } else { 1625 InetSocketAddress *addr = g_new(InetSocketAddress, 1); 1626 1627 if (inet_parse(addr, host_spec, errp)) { 1628 goto out_inet; 1629 } 1630 1631 qdict_put_str(options, "server.type", "inet"); 1632 qdict_put_str(options, "server.host", addr->host); 1633 qdict_put_str(options, "server.port", addr->port); 1634 out_inet: 1635 qapi_free_InetSocketAddress(addr); 1636 } 1637 } 1638 1639 static bool nbd_process_legacy_socket_options(QDict *output_options, 1640 QemuOpts *legacy_opts, 1641 Error **errp) 1642 { 1643 const char *path = qemu_opt_get(legacy_opts, "path"); 1644 const char *host = qemu_opt_get(legacy_opts, "host"); 1645 const char *port = qemu_opt_get(legacy_opts, "port"); 1646 const QDictEntry *e; 1647 1648 if (!path && !host && !port) { 1649 return true; 1650 } 1651 1652 for (e = qdict_first(output_options); e; e = qdict_next(output_options, e)) 1653 { 1654 if (strstart(e->key, "server.", NULL)) { 1655 error_setg(errp, "Cannot use 'server' and path/host/port at the " 1656 "same time"); 1657 return false; 1658 } 1659 } 1660 1661 if (path && host) { 1662 error_setg(errp, "path and host may not be used at the same time"); 1663 return false; 1664 } else if (path) { 1665 if (port) { 1666 error_setg(errp, "port may not be used without host"); 1667 return false; 1668 } 1669 1670 qdict_put_str(output_options, "server.type", "unix"); 1671 qdict_put_str(output_options, "server.path", path); 1672 } else if (host) { 1673 qdict_put_str(output_options, "server.type", "inet"); 1674 qdict_put_str(output_options, "server.host", host); 1675 qdict_put_str(output_options, "server.port", 1676 port ?: stringify(NBD_DEFAULT_PORT)); 1677 } 1678 1679 return true; 1680 } 1681 1682 static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, 1683 Error **errp) 1684 { 1685 SocketAddress *saddr = NULL; 1686 QDict *addr = NULL; 1687 Visitor *iv = NULL; 1688 1689 qdict_extract_subqdict(options, &addr, "server."); 1690 if (!qdict_size(addr)) { 1691 error_setg(errp, "NBD server address missing"); 1692 goto done; 1693 } 1694 1695 iv = qobject_input_visitor_new_flat_confused(addr, errp); 1696 if (!iv) { 1697 goto done; 1698 } 1699 1700 if (!visit_type_SocketAddress(iv, NULL, &saddr, errp)) { 1701 goto done; 1702 } 1703 1704 if (socket_address_parse_named_fd(saddr, errp) < 0) { 1705 qapi_free_SocketAddress(saddr); 1706 saddr = NULL; 1707 goto done; 1708 } 1709 1710 done: 1711 qobject_unref(addr); 1712 visit_free(iv); 1713 return saddr; 1714 } 1715 1716 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 1717 { 1718 Object *obj; 1719 QCryptoTLSCreds *creds; 1720 1721 obj = object_resolve_path_component( 1722 object_get_objects_root(), id); 1723 if (!obj) { 1724 error_setg(errp, "No TLS credentials with id '%s'", 1725 id); 1726 return NULL; 1727 } 1728 creds = (QCryptoTLSCreds *) 1729 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 1730 if (!creds) { 1731 error_setg(errp, "Object with id '%s' is not TLS credentials", 1732 id); 1733 return NULL; 1734 } 1735 1736 if (!qcrypto_tls_creds_check_endpoint(creds, 1737 QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT, 1738 errp)) { 1739 return NULL; 1740 } 1741 object_ref(obj); 1742 return creds; 1743 } 1744 1745 1746 static QemuOptsList nbd_runtime_opts = { 1747 .name = "nbd", 1748 .head = QTAILQ_HEAD_INITIALIZER(nbd_runtime_opts.head), 1749 .desc = { 1750 { 1751 .name = "host", 1752 .type = QEMU_OPT_STRING, 1753 .help = "TCP host to connect to", 1754 }, 1755 { 1756 .name = "port", 1757 .type = QEMU_OPT_STRING, 1758 .help = "TCP port to connect to", 1759 }, 1760 { 1761 .name = "path", 1762 .type = QEMU_OPT_STRING, 1763 .help = "Unix socket path to connect to", 1764 }, 1765 { 1766 .name = "export", 1767 .type = QEMU_OPT_STRING, 1768 .help = "Name of the NBD export to open", 1769 }, 1770 { 1771 .name = "tls-creds", 1772 .type = QEMU_OPT_STRING, 1773 .help = "ID of the TLS credentials to use", 1774 }, 1775 { 1776 .name = "tls-hostname", 1777 .type = QEMU_OPT_STRING, 1778 .help = "Override hostname for validating TLS x509 certificate", 1779 }, 1780 { 1781 .name = "x-dirty-bitmap", 1782 .type = QEMU_OPT_STRING, 1783 .help = "experimental: expose named dirty bitmap in place of " 1784 "block status", 1785 }, 1786 { 1787 .name = "reconnect-delay", 1788 .type = QEMU_OPT_NUMBER, 1789 .help = "On an unexpected disconnect, the nbd client tries to " 1790 "connect again until succeeding or encountering a serious " 1791 "error. During the first @reconnect-delay seconds, all " 1792 "requests are paused and will be rerun on a successful " 1793 "reconnect. After that time, any delayed requests and all " 1794 "future requests before a successful reconnect will " 1795 "immediately fail. Default 0", 1796 }, 1797 { 1798 .name = "open-timeout", 1799 .type = QEMU_OPT_NUMBER, 1800 .help = "In seconds. If zero, the nbd driver tries the connection " 1801 "only once, and fails to open if the connection fails. " 1802 "If non-zero, the nbd driver will repeat connection " 1803 "attempts until successful or until @open-timeout seconds " 1804 "have elapsed. Default 0", 1805 }, 1806 { /* end of list */ } 1807 }, 1808 }; 1809 1810 static int nbd_process_options(BlockDriverState *bs, QDict *options, 1811 Error **errp) 1812 { 1813 BDRVNBDState *s = bs->opaque; 1814 QemuOpts *opts; 1815 int ret = -EINVAL; 1816 1817 opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort); 1818 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 1819 goto error; 1820 } 1821 1822 /* Translate @host, @port, and @path to a SocketAddress */ 1823 if (!nbd_process_legacy_socket_options(options, opts, errp)) { 1824 goto error; 1825 } 1826 1827 /* Pop the config into our state object. Exit if invalid. */ 1828 s->saddr = nbd_config(s, options, errp); 1829 if (!s->saddr) { 1830 goto error; 1831 } 1832 1833 s->export = g_strdup(qemu_opt_get(opts, "export")); 1834 if (s->export && strlen(s->export) > NBD_MAX_STRING_SIZE) { 1835 error_setg(errp, "export name too long to send to server"); 1836 goto error; 1837 } 1838 1839 s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds")); 1840 if (s->tlscredsid) { 1841 s->tlscreds = nbd_get_tls_creds(s->tlscredsid, errp); 1842 if (!s->tlscreds) { 1843 goto error; 1844 } 1845 1846 s->tlshostname = g_strdup(qemu_opt_get(opts, "tls-hostname")); 1847 if (!s->tlshostname && 1848 s->saddr->type == SOCKET_ADDRESS_TYPE_INET) { 1849 s->tlshostname = g_strdup(s->saddr->u.inet.host); 1850 } 1851 } 1852 1853 s->x_dirty_bitmap = g_strdup(qemu_opt_get(opts, "x-dirty-bitmap")); 1854 if (s->x_dirty_bitmap && strlen(s->x_dirty_bitmap) > NBD_MAX_STRING_SIZE) { 1855 error_setg(errp, "x-dirty-bitmap query too long to send to server"); 1856 goto error; 1857 } 1858 1859 s->reconnect_delay = qemu_opt_get_number(opts, "reconnect-delay", 0); 1860 s->open_timeout = qemu_opt_get_number(opts, "open-timeout", 0); 1861 1862 ret = 0; 1863 1864 error: 1865 qemu_opts_del(opts); 1866 return ret; 1867 } 1868 1869 static int nbd_open(BlockDriverState *bs, QDict *options, int flags, 1870 Error **errp) 1871 { 1872 int ret; 1873 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1874 1875 s->bs = bs; 1876 qemu_mutex_init(&s->requests_lock); 1877 qemu_co_queue_init(&s->free_sema); 1878 qemu_co_mutex_init(&s->send_mutex); 1879 qemu_co_mutex_init(&s->receive_mutex); 1880 1881 if (!yank_register_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name), errp)) { 1882 return -EEXIST; 1883 } 1884 1885 ret = nbd_process_options(bs, options, errp); 1886 if (ret < 0) { 1887 goto fail; 1888 } 1889 1890 s->conn = nbd_client_connection_new(s->saddr, true, s->export, 1891 s->x_dirty_bitmap, s->tlscreds, 1892 s->tlshostname); 1893 1894 if (s->open_timeout) { 1895 nbd_client_connection_enable_retry(s->conn); 1896 open_timer_init(s, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + 1897 s->open_timeout * NANOSECONDS_PER_SECOND); 1898 } 1899 1900 s->state = NBD_CLIENT_CONNECTING_WAIT; 1901 ret = nbd_do_establish_connection(bs, true, errp); 1902 if (ret < 0) { 1903 goto fail; 1904 } 1905 1906 /* 1907 * The connect attempt is done, so we no longer need this timer. 1908 * Delete it, because we do not want it to be around when this node 1909 * is drained or closed. 1910 */ 1911 open_timer_del(s); 1912 1913 nbd_client_connection_enable_retry(s->conn); 1914 1915 return 0; 1916 1917 fail: 1918 open_timer_del(s); 1919 nbd_clear_bdrvstate(bs); 1920 return ret; 1921 } 1922 1923 static int coroutine_fn nbd_co_flush(BlockDriverState *bs) 1924 { 1925 return nbd_client_co_flush(bs); 1926 } 1927 1928 static void nbd_refresh_limits(BlockDriverState *bs, Error **errp) 1929 { 1930 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1931 uint32_t min = s->info.min_block; 1932 uint32_t max = MIN_NON_ZERO(NBD_MAX_BUFFER_SIZE, s->info.max_block); 1933 1934 /* 1935 * If the server did not advertise an alignment: 1936 * - a size that is not sector-aligned implies that an alignment 1937 * of 1 can be used to access those tail bytes 1938 * - advertisement of block status requires an alignment of 1, so 1939 * that we don't violate block layer constraints that block 1940 * status is always aligned (as we can't control whether the 1941 * server will report sub-sector extents, such as a hole at EOF 1942 * on an unaligned POSIX file) 1943 * - otherwise, assume the server is so old that we are safer avoiding 1944 * sub-sector requests 1945 */ 1946 if (!min) { 1947 min = (!QEMU_IS_ALIGNED(s->info.size, BDRV_SECTOR_SIZE) || 1948 s->info.base_allocation) ? 1 : BDRV_SECTOR_SIZE; 1949 } 1950 1951 bs->bl.request_alignment = min; 1952 bs->bl.max_pdiscard = QEMU_ALIGN_DOWN(INT_MAX, min); 1953 bs->bl.max_pwrite_zeroes = max; 1954 bs->bl.max_transfer = max; 1955 1956 if (s->info.opt_block && 1957 s->info.opt_block > bs->bl.opt_transfer) { 1958 bs->bl.opt_transfer = s->info.opt_block; 1959 } 1960 } 1961 1962 static void nbd_close(BlockDriverState *bs) 1963 { 1964 nbd_client_close(bs); 1965 nbd_clear_bdrvstate(bs); 1966 } 1967 1968 /* 1969 * NBD cannot truncate, but if the caller asks to truncate to the same size, or 1970 * to a smaller size with exact=false, there is no reason to fail the 1971 * operation. 1972 * 1973 * Preallocation mode is ignored since it does not seems useful to fail when 1974 * we never change anything. 1975 */ 1976 static int coroutine_fn nbd_co_truncate(BlockDriverState *bs, int64_t offset, 1977 bool exact, PreallocMode prealloc, 1978 BdrvRequestFlags flags, Error **errp) 1979 { 1980 BDRVNBDState *s = bs->opaque; 1981 1982 if (offset != s->info.size && exact) { 1983 error_setg(errp, "Cannot resize NBD nodes"); 1984 return -ENOTSUP; 1985 } 1986 1987 if (offset > s->info.size) { 1988 error_setg(errp, "Cannot grow NBD nodes"); 1989 return -EINVAL; 1990 } 1991 1992 return 0; 1993 } 1994 1995 static int64_t nbd_getlength(BlockDriverState *bs) 1996 { 1997 BDRVNBDState *s = bs->opaque; 1998 1999 return s->info.size; 2000 } 2001 2002 static void nbd_refresh_filename(BlockDriverState *bs) 2003 { 2004 BDRVNBDState *s = bs->opaque; 2005 const char *host = NULL, *port = NULL, *path = NULL; 2006 size_t len = 0; 2007 2008 if (s->saddr->type == SOCKET_ADDRESS_TYPE_INET) { 2009 const InetSocketAddress *inet = &s->saddr->u.inet; 2010 if (!inet->has_ipv4 && !inet->has_ipv6 && !inet->has_to) { 2011 host = inet->host; 2012 port = inet->port; 2013 } 2014 } else if (s->saddr->type == SOCKET_ADDRESS_TYPE_UNIX) { 2015 path = s->saddr->u.q_unix.path; 2016 } /* else can't represent as pseudo-filename */ 2017 2018 if (path && s->export) { 2019 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2020 "nbd+unix:///%s?socket=%s", s->export, path); 2021 } else if (path && !s->export) { 2022 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2023 "nbd+unix://?socket=%s", path); 2024 } else if (host && s->export) { 2025 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2026 "nbd://%s:%s/%s", host, port, s->export); 2027 } else if (host && !s->export) { 2028 len = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2029 "nbd://%s:%s", host, port); 2030 } 2031 if (len >= sizeof(bs->exact_filename)) { 2032 /* Name is too long to represent exactly, so leave it empty. */ 2033 bs->exact_filename[0] = '\0'; 2034 } 2035 } 2036 2037 static char *nbd_dirname(BlockDriverState *bs, Error **errp) 2038 { 2039 /* The generic bdrv_dirname() implementation is able to work out some 2040 * directory name for NBD nodes, but that would be wrong. So far there is no 2041 * specification for how "export paths" would work, so NBD does not have 2042 * directory names. */ 2043 error_setg(errp, "Cannot generate a base directory for NBD nodes"); 2044 return NULL; 2045 } 2046 2047 static const char *const nbd_strong_runtime_opts[] = { 2048 "path", 2049 "host", 2050 "port", 2051 "export", 2052 "tls-creds", 2053 "tls-hostname", 2054 "server.", 2055 2056 NULL 2057 }; 2058 2059 static void nbd_cancel_in_flight(BlockDriverState *bs) 2060 { 2061 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 2062 2063 reconnect_delay_timer_del(s); 2064 2065 qemu_mutex_lock(&s->requests_lock); 2066 if (s->state == NBD_CLIENT_CONNECTING_WAIT) { 2067 s->state = NBD_CLIENT_CONNECTING_NOWAIT; 2068 } 2069 qemu_mutex_unlock(&s->requests_lock); 2070 2071 nbd_co_establish_connection_cancel(s->conn); 2072 } 2073 2074 static void nbd_attach_aio_context(BlockDriverState *bs, 2075 AioContext *new_context) 2076 { 2077 BDRVNBDState *s = bs->opaque; 2078 2079 /* The open_timer is used only during nbd_open() */ 2080 assert(!s->open_timer); 2081 2082 /* 2083 * The reconnect_delay_timer is scheduled in I/O paths when the 2084 * connection is lost, to cancel the reconnection attempt after a 2085 * given time. Once this attempt is done (successfully or not), 2086 * nbd_reconnect_attempt() ensures the timer is deleted before the 2087 * respective I/O request is resumed. 2088 * Since the AioContext can only be changed when a node is drained, 2089 * the reconnect_delay_timer cannot be active here. 2090 */ 2091 assert(!s->reconnect_delay_timer); 2092 2093 if (s->ioc) { 2094 qio_channel_attach_aio_context(s->ioc, new_context); 2095 } 2096 } 2097 2098 static void nbd_detach_aio_context(BlockDriverState *bs) 2099 { 2100 BDRVNBDState *s = bs->opaque; 2101 2102 assert(!s->open_timer); 2103 assert(!s->reconnect_delay_timer); 2104 2105 if (s->ioc) { 2106 qio_channel_detach_aio_context(s->ioc); 2107 } 2108 } 2109 2110 static BlockDriver bdrv_nbd = { 2111 .format_name = "nbd", 2112 .protocol_name = "nbd", 2113 .instance_size = sizeof(BDRVNBDState), 2114 .bdrv_parse_filename = nbd_parse_filename, 2115 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2116 .create_opts = &bdrv_create_opts_simple, 2117 .bdrv_file_open = nbd_open, 2118 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2119 .bdrv_co_preadv = nbd_client_co_preadv, 2120 .bdrv_co_pwritev = nbd_client_co_pwritev, 2121 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2122 .bdrv_close = nbd_close, 2123 .bdrv_co_flush_to_os = nbd_co_flush, 2124 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2125 .bdrv_refresh_limits = nbd_refresh_limits, 2126 .bdrv_co_truncate = nbd_co_truncate, 2127 .bdrv_getlength = nbd_getlength, 2128 .bdrv_refresh_filename = nbd_refresh_filename, 2129 .bdrv_co_block_status = nbd_client_co_block_status, 2130 .bdrv_dirname = nbd_dirname, 2131 .strong_runtime_opts = nbd_strong_runtime_opts, 2132 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2133 2134 .bdrv_attach_aio_context = nbd_attach_aio_context, 2135 .bdrv_detach_aio_context = nbd_detach_aio_context, 2136 }; 2137 2138 static BlockDriver bdrv_nbd_tcp = { 2139 .format_name = "nbd", 2140 .protocol_name = "nbd+tcp", 2141 .instance_size = sizeof(BDRVNBDState), 2142 .bdrv_parse_filename = nbd_parse_filename, 2143 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2144 .create_opts = &bdrv_create_opts_simple, 2145 .bdrv_file_open = nbd_open, 2146 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2147 .bdrv_co_preadv = nbd_client_co_preadv, 2148 .bdrv_co_pwritev = nbd_client_co_pwritev, 2149 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2150 .bdrv_close = nbd_close, 2151 .bdrv_co_flush_to_os = nbd_co_flush, 2152 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2153 .bdrv_refresh_limits = nbd_refresh_limits, 2154 .bdrv_co_truncate = nbd_co_truncate, 2155 .bdrv_getlength = nbd_getlength, 2156 .bdrv_refresh_filename = nbd_refresh_filename, 2157 .bdrv_co_block_status = nbd_client_co_block_status, 2158 .bdrv_dirname = nbd_dirname, 2159 .strong_runtime_opts = nbd_strong_runtime_opts, 2160 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2161 2162 .bdrv_attach_aio_context = nbd_attach_aio_context, 2163 .bdrv_detach_aio_context = nbd_detach_aio_context, 2164 }; 2165 2166 static BlockDriver bdrv_nbd_unix = { 2167 .format_name = "nbd", 2168 .protocol_name = "nbd+unix", 2169 .instance_size = sizeof(BDRVNBDState), 2170 .bdrv_parse_filename = nbd_parse_filename, 2171 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2172 .create_opts = &bdrv_create_opts_simple, 2173 .bdrv_file_open = nbd_open, 2174 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2175 .bdrv_co_preadv = nbd_client_co_preadv, 2176 .bdrv_co_pwritev = nbd_client_co_pwritev, 2177 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2178 .bdrv_close = nbd_close, 2179 .bdrv_co_flush_to_os = nbd_co_flush, 2180 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2181 .bdrv_refresh_limits = nbd_refresh_limits, 2182 .bdrv_co_truncate = nbd_co_truncate, 2183 .bdrv_getlength = nbd_getlength, 2184 .bdrv_refresh_filename = nbd_refresh_filename, 2185 .bdrv_co_block_status = nbd_client_co_block_status, 2186 .bdrv_dirname = nbd_dirname, 2187 .strong_runtime_opts = nbd_strong_runtime_opts, 2188 .bdrv_cancel_in_flight = nbd_cancel_in_flight, 2189 2190 .bdrv_attach_aio_context = nbd_attach_aio_context, 2191 .bdrv_detach_aio_context = nbd_detach_aio_context, 2192 }; 2193 2194 static void bdrv_nbd_init(void) 2195 { 2196 bdrv_register(&bdrv_nbd); 2197 bdrv_register(&bdrv_nbd_tcp); 2198 bdrv_register(&bdrv_nbd_unix); 2199 } 2200 2201 block_init(bdrv_nbd_init); 2202