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 42 #include "block/qdict.h" 43 #include "block/nbd.h" 44 #include "block/block_int.h" 45 46 #define EN_OPTSTR ":exportname=" 47 #define MAX_NBD_REQUESTS 16 48 49 #define HANDLE_TO_INDEX(bs, handle) ((handle) ^ (uint64_t)(intptr_t)(bs)) 50 #define INDEX_TO_HANDLE(bs, index) ((index) ^ (uint64_t)(intptr_t)(bs)) 51 52 typedef struct { 53 Coroutine *coroutine; 54 uint64_t offset; /* original offset of the request */ 55 bool receiving; /* waiting for connection_co? */ 56 } NBDClientRequest; 57 58 typedef enum NBDClientState { 59 NBD_CLIENT_CONNECTING_WAIT, 60 NBD_CLIENT_CONNECTING_NOWAIT, 61 NBD_CLIENT_CONNECTED, 62 NBD_CLIENT_QUIT 63 } NBDClientState; 64 65 typedef struct BDRVNBDState { 66 QIOChannelSocket *sioc; /* The master data channel */ 67 QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */ 68 NBDExportInfo info; 69 70 CoMutex send_mutex; 71 CoQueue free_sema; 72 Coroutine *connection_co; 73 Coroutine *teardown_co; 74 QemuCoSleepState *connection_co_sleep_ns_state; 75 bool drained; 76 bool wait_drained_end; 77 int in_flight; 78 NBDClientState state; 79 int connect_status; 80 Error *connect_err; 81 bool wait_in_flight; 82 83 NBDClientRequest requests[MAX_NBD_REQUESTS]; 84 NBDReply reply; 85 BlockDriverState *bs; 86 87 /* Connection parameters */ 88 uint32_t reconnect_delay; 89 SocketAddress *saddr; 90 char *export, *tlscredsid; 91 QCryptoTLSCreds *tlscreds; 92 const char *hostname; 93 char *x_dirty_bitmap; 94 } BDRVNBDState; 95 96 static int nbd_client_connect(BlockDriverState *bs, Error **errp); 97 98 static void nbd_clear_bdrvstate(BDRVNBDState *s) 99 { 100 object_unref(OBJECT(s->tlscreds)); 101 qapi_free_SocketAddress(s->saddr); 102 s->saddr = NULL; 103 g_free(s->export); 104 s->export = NULL; 105 g_free(s->tlscredsid); 106 s->tlscredsid = NULL; 107 g_free(s->x_dirty_bitmap); 108 s->x_dirty_bitmap = NULL; 109 } 110 111 static void nbd_channel_error(BDRVNBDState *s, int ret) 112 { 113 if (ret == -EIO) { 114 if (s->state == NBD_CLIENT_CONNECTED) { 115 s->state = s->reconnect_delay ? NBD_CLIENT_CONNECTING_WAIT : 116 NBD_CLIENT_CONNECTING_NOWAIT; 117 } 118 } else { 119 if (s->state == NBD_CLIENT_CONNECTED) { 120 qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 121 } 122 s->state = NBD_CLIENT_QUIT; 123 } 124 } 125 126 static void nbd_recv_coroutines_wake_all(BDRVNBDState *s) 127 { 128 int i; 129 130 for (i = 0; i < MAX_NBD_REQUESTS; i++) { 131 NBDClientRequest *req = &s->requests[i]; 132 133 if (req->coroutine && req->receiving) { 134 aio_co_wake(req->coroutine); 135 } 136 } 137 } 138 139 static void nbd_client_detach_aio_context(BlockDriverState *bs) 140 { 141 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 142 143 qio_channel_detach_aio_context(QIO_CHANNEL(s->ioc)); 144 } 145 146 static void nbd_client_attach_aio_context_bh(void *opaque) 147 { 148 BlockDriverState *bs = opaque; 149 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 150 151 /* 152 * The node is still drained, so we know the coroutine has yielded in 153 * nbd_read_eof(), the only place where bs->in_flight can reach 0, or it is 154 * entered for the first time. Both places are safe for entering the 155 * coroutine. 156 */ 157 qemu_aio_coroutine_enter(bs->aio_context, s->connection_co); 158 bdrv_dec_in_flight(bs); 159 } 160 161 static void nbd_client_attach_aio_context(BlockDriverState *bs, 162 AioContext *new_context) 163 { 164 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 165 166 /* 167 * s->connection_co is either yielded from nbd_receive_reply or from 168 * nbd_co_reconnect_loop() 169 */ 170 if (s->state == NBD_CLIENT_CONNECTED) { 171 qio_channel_attach_aio_context(QIO_CHANNEL(s->ioc), new_context); 172 } 173 174 bdrv_inc_in_flight(bs); 175 176 /* 177 * Need to wait here for the BH to run because the BH must run while the 178 * node is still drained. 179 */ 180 aio_wait_bh_oneshot(new_context, nbd_client_attach_aio_context_bh, bs); 181 } 182 183 static void coroutine_fn nbd_client_co_drain_begin(BlockDriverState *bs) 184 { 185 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 186 187 s->drained = true; 188 if (s->connection_co_sleep_ns_state) { 189 qemu_co_sleep_wake(s->connection_co_sleep_ns_state); 190 } 191 } 192 193 static void coroutine_fn nbd_client_co_drain_end(BlockDriverState *bs) 194 { 195 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 196 197 s->drained = false; 198 if (s->wait_drained_end) { 199 s->wait_drained_end = false; 200 aio_co_wake(s->connection_co); 201 } 202 } 203 204 205 static void nbd_teardown_connection(BlockDriverState *bs) 206 { 207 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 208 209 if (s->state == NBD_CLIENT_CONNECTED) { 210 /* finish any pending coroutines */ 211 assert(s->ioc); 212 qio_channel_shutdown(s->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); 213 } 214 s->state = NBD_CLIENT_QUIT; 215 if (s->connection_co) { 216 if (s->connection_co_sleep_ns_state) { 217 qemu_co_sleep_wake(s->connection_co_sleep_ns_state); 218 } 219 } 220 if (qemu_in_coroutine()) { 221 s->teardown_co = qemu_coroutine_self(); 222 /* connection_co resumes us when it terminates */ 223 qemu_coroutine_yield(); 224 s->teardown_co = NULL; 225 } else { 226 BDRV_POLL_WHILE(bs, s->connection_co); 227 } 228 assert(!s->connection_co); 229 } 230 231 static bool nbd_client_connecting(BDRVNBDState *s) 232 { 233 return s->state == NBD_CLIENT_CONNECTING_WAIT || 234 s->state == NBD_CLIENT_CONNECTING_NOWAIT; 235 } 236 237 static bool nbd_client_connecting_wait(BDRVNBDState *s) 238 { 239 return s->state == NBD_CLIENT_CONNECTING_WAIT; 240 } 241 242 static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) 243 { 244 Error *local_err = NULL; 245 246 if (!nbd_client_connecting(s)) { 247 return; 248 } 249 250 /* Wait for completion of all in-flight requests */ 251 252 qemu_co_mutex_lock(&s->send_mutex); 253 254 while (s->in_flight > 0) { 255 qemu_co_mutex_unlock(&s->send_mutex); 256 nbd_recv_coroutines_wake_all(s); 257 s->wait_in_flight = true; 258 qemu_coroutine_yield(); 259 s->wait_in_flight = false; 260 qemu_co_mutex_lock(&s->send_mutex); 261 } 262 263 qemu_co_mutex_unlock(&s->send_mutex); 264 265 if (!nbd_client_connecting(s)) { 266 return; 267 } 268 269 /* 270 * Now we are sure that nobody is accessing the channel, and no one will 271 * try until we set the state to CONNECTED. 272 */ 273 274 /* Finalize previous connection if any */ 275 if (s->ioc) { 276 nbd_client_detach_aio_context(s->bs); 277 object_unref(OBJECT(s->sioc)); 278 s->sioc = NULL; 279 object_unref(OBJECT(s->ioc)); 280 s->ioc = NULL; 281 } 282 283 s->connect_status = nbd_client_connect(s->bs, &local_err); 284 error_free(s->connect_err); 285 s->connect_err = NULL; 286 error_propagate(&s->connect_err, local_err); 287 288 if (s->connect_status < 0) { 289 /* failed attempt */ 290 return; 291 } 292 293 /* successfully connected */ 294 s->state = NBD_CLIENT_CONNECTED; 295 qemu_co_queue_restart_all(&s->free_sema); 296 } 297 298 static coroutine_fn void nbd_co_reconnect_loop(BDRVNBDState *s) 299 { 300 uint64_t start_time_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); 301 uint64_t delay_ns = s->reconnect_delay * NANOSECONDS_PER_SECOND; 302 uint64_t timeout = 1 * NANOSECONDS_PER_SECOND; 303 uint64_t max_timeout = 16 * NANOSECONDS_PER_SECOND; 304 305 nbd_reconnect_attempt(s); 306 307 while (nbd_client_connecting(s)) { 308 if (s->state == NBD_CLIENT_CONNECTING_WAIT && 309 qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - start_time_ns > delay_ns) 310 { 311 s->state = NBD_CLIENT_CONNECTING_NOWAIT; 312 qemu_co_queue_restart_all(&s->free_sema); 313 } 314 315 qemu_co_sleep_ns_wakeable(QEMU_CLOCK_REALTIME, timeout, 316 &s->connection_co_sleep_ns_state); 317 if (s->drained) { 318 bdrv_dec_in_flight(s->bs); 319 s->wait_drained_end = true; 320 while (s->drained) { 321 /* 322 * We may be entered once from nbd_client_attach_aio_context_bh 323 * and then from nbd_client_co_drain_end. So here is a loop. 324 */ 325 qemu_coroutine_yield(); 326 } 327 bdrv_inc_in_flight(s->bs); 328 } 329 if (timeout < max_timeout) { 330 timeout *= 2; 331 } 332 333 nbd_reconnect_attempt(s); 334 } 335 } 336 337 static coroutine_fn void nbd_connection_entry(void *opaque) 338 { 339 BDRVNBDState *s = opaque; 340 uint64_t i; 341 int ret = 0; 342 Error *local_err = NULL; 343 344 while (s->state != NBD_CLIENT_QUIT) { 345 /* 346 * The NBD client can only really be considered idle when it has 347 * yielded from qio_channel_readv_all_eof(), waiting for data. This is 348 * the point where the additional scheduled coroutine entry happens 349 * after nbd_client_attach_aio_context(). 350 * 351 * Therefore we keep an additional in_flight reference all the time and 352 * only drop it temporarily here. 353 */ 354 355 if (nbd_client_connecting(s)) { 356 nbd_co_reconnect_loop(s); 357 } 358 359 if (s->state != NBD_CLIENT_CONNECTED) { 360 continue; 361 } 362 363 assert(s->reply.handle == 0); 364 ret = nbd_receive_reply(s->bs, s->ioc, &s->reply, &local_err); 365 366 if (local_err) { 367 trace_nbd_read_reply_entry_fail(ret, error_get_pretty(local_err)); 368 error_free(local_err); 369 local_err = NULL; 370 } 371 if (ret <= 0) { 372 nbd_channel_error(s, ret ? ret : -EIO); 373 continue; 374 } 375 376 /* 377 * There's no need for a mutex on the receive side, because the 378 * handler acts as a synchronization point and ensures that only 379 * one coroutine is called until the reply finishes. 380 */ 381 i = HANDLE_TO_INDEX(s, s->reply.handle); 382 if (i >= MAX_NBD_REQUESTS || 383 !s->requests[i].coroutine || 384 !s->requests[i].receiving || 385 (nbd_reply_is_structured(&s->reply) && !s->info.structured_reply)) 386 { 387 nbd_channel_error(s, -EINVAL); 388 continue; 389 } 390 391 /* 392 * We're woken up again by the request itself. Note that there 393 * is no race between yielding and reentering connection_co. This 394 * is because: 395 * 396 * - if the request runs on the same AioContext, it is only 397 * entered after we yield 398 * 399 * - if the request runs on a different AioContext, reentering 400 * connection_co happens through a bottom half, which can only 401 * run after we yield. 402 */ 403 aio_co_wake(s->requests[i].coroutine); 404 qemu_coroutine_yield(); 405 } 406 407 qemu_co_queue_restart_all(&s->free_sema); 408 nbd_recv_coroutines_wake_all(s); 409 bdrv_dec_in_flight(s->bs); 410 411 s->connection_co = NULL; 412 if (s->ioc) { 413 nbd_client_detach_aio_context(s->bs); 414 object_unref(OBJECT(s->sioc)); 415 s->sioc = NULL; 416 object_unref(OBJECT(s->ioc)); 417 s->ioc = NULL; 418 } 419 420 if (s->teardown_co) { 421 aio_co_wake(s->teardown_co); 422 } 423 aio_wait_kick(); 424 } 425 426 static int nbd_co_send_request(BlockDriverState *bs, 427 NBDRequest *request, 428 QEMUIOVector *qiov) 429 { 430 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 431 int rc, i = -1; 432 433 qemu_co_mutex_lock(&s->send_mutex); 434 while (s->in_flight == MAX_NBD_REQUESTS || nbd_client_connecting_wait(s)) { 435 qemu_co_queue_wait(&s->free_sema, &s->send_mutex); 436 } 437 438 if (s->state != NBD_CLIENT_CONNECTED) { 439 rc = -EIO; 440 goto err; 441 } 442 443 s->in_flight++; 444 445 for (i = 0; i < MAX_NBD_REQUESTS; i++) { 446 if (s->requests[i].coroutine == NULL) { 447 break; 448 } 449 } 450 451 g_assert(qemu_in_coroutine()); 452 assert(i < MAX_NBD_REQUESTS); 453 454 s->requests[i].coroutine = qemu_coroutine_self(); 455 s->requests[i].offset = request->from; 456 s->requests[i].receiving = false; 457 458 request->handle = INDEX_TO_HANDLE(s, i); 459 460 assert(s->ioc); 461 462 if (qiov) { 463 qio_channel_set_cork(s->ioc, true); 464 rc = nbd_send_request(s->ioc, request); 465 if (rc >= 0 && s->state == NBD_CLIENT_CONNECTED) { 466 if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov, 467 NULL) < 0) { 468 rc = -EIO; 469 } 470 } else if (rc >= 0) { 471 rc = -EIO; 472 } 473 qio_channel_set_cork(s->ioc, false); 474 } else { 475 rc = nbd_send_request(s->ioc, request); 476 } 477 478 err: 479 if (rc < 0) { 480 nbd_channel_error(s, rc); 481 if (i != -1) { 482 s->requests[i].coroutine = NULL; 483 s->in_flight--; 484 } 485 if (s->in_flight == 0 && s->wait_in_flight) { 486 aio_co_wake(s->connection_co); 487 } else { 488 qemu_co_queue_next(&s->free_sema); 489 } 490 } 491 qemu_co_mutex_unlock(&s->send_mutex); 492 return rc; 493 } 494 495 static inline uint16_t payload_advance16(uint8_t **payload) 496 { 497 *payload += 2; 498 return lduw_be_p(*payload - 2); 499 } 500 501 static inline uint32_t payload_advance32(uint8_t **payload) 502 { 503 *payload += 4; 504 return ldl_be_p(*payload - 4); 505 } 506 507 static inline uint64_t payload_advance64(uint8_t **payload) 508 { 509 *payload += 8; 510 return ldq_be_p(*payload - 8); 511 } 512 513 static int nbd_parse_offset_hole_payload(BDRVNBDState *s, 514 NBDStructuredReplyChunk *chunk, 515 uint8_t *payload, uint64_t orig_offset, 516 QEMUIOVector *qiov, Error **errp) 517 { 518 uint64_t offset; 519 uint32_t hole_size; 520 521 if (chunk->length != sizeof(offset) + sizeof(hole_size)) { 522 error_setg(errp, "Protocol error: invalid payload for " 523 "NBD_REPLY_TYPE_OFFSET_HOLE"); 524 return -EINVAL; 525 } 526 527 offset = payload_advance64(&payload); 528 hole_size = payload_advance32(&payload); 529 530 if (!hole_size || offset < orig_offset || hole_size > qiov->size || 531 offset > orig_offset + qiov->size - hole_size) { 532 error_setg(errp, "Protocol error: server sent chunk exceeding requested" 533 " region"); 534 return -EINVAL; 535 } 536 if (s->info.min_block && 537 !QEMU_IS_ALIGNED(hole_size, s->info.min_block)) { 538 trace_nbd_structured_read_compliance("hole"); 539 } 540 541 qemu_iovec_memset(qiov, offset - orig_offset, 0, hole_size); 542 543 return 0; 544 } 545 546 /* 547 * nbd_parse_blockstatus_payload 548 * Based on our request, we expect only one extent in reply, for the 549 * base:allocation context. 550 */ 551 static int nbd_parse_blockstatus_payload(BDRVNBDState *s, 552 NBDStructuredReplyChunk *chunk, 553 uint8_t *payload, uint64_t orig_length, 554 NBDExtent *extent, Error **errp) 555 { 556 uint32_t context_id; 557 558 /* The server succeeded, so it must have sent [at least] one extent */ 559 if (chunk->length < sizeof(context_id) + sizeof(*extent)) { 560 error_setg(errp, "Protocol error: invalid payload for " 561 "NBD_REPLY_TYPE_BLOCK_STATUS"); 562 return -EINVAL; 563 } 564 565 context_id = payload_advance32(&payload); 566 if (s->info.context_id != context_id) { 567 error_setg(errp, "Protocol error: unexpected context id %d for " 568 "NBD_REPLY_TYPE_BLOCK_STATUS, when negotiated context " 569 "id is %d", context_id, 570 s->info.context_id); 571 return -EINVAL; 572 } 573 574 extent->length = payload_advance32(&payload); 575 extent->flags = payload_advance32(&payload); 576 577 if (extent->length == 0) { 578 error_setg(errp, "Protocol error: server sent status chunk with " 579 "zero length"); 580 return -EINVAL; 581 } 582 583 /* 584 * A server sending unaligned block status is in violation of the 585 * protocol, but as qemu-nbd 3.1 is such a server (at least for 586 * POSIX files that are not a multiple of 512 bytes, since qemu 587 * rounds files up to 512-byte multiples but lseek(SEEK_HOLE) 588 * still sees an implicit hole beyond the real EOF), it's nicer to 589 * work around the misbehaving server. If the request included 590 * more than the final unaligned block, truncate it back to an 591 * aligned result; if the request was only the final block, round 592 * up to the full block and change the status to fully-allocated 593 * (always a safe status, even if it loses information). 594 */ 595 if (s->info.min_block && !QEMU_IS_ALIGNED(extent->length, 596 s->info.min_block)) { 597 trace_nbd_parse_blockstatus_compliance("extent length is unaligned"); 598 if (extent->length > s->info.min_block) { 599 extent->length = QEMU_ALIGN_DOWN(extent->length, 600 s->info.min_block); 601 } else { 602 extent->length = s->info.min_block; 603 extent->flags = 0; 604 } 605 } 606 607 /* 608 * We used NBD_CMD_FLAG_REQ_ONE, so the server should not have 609 * sent us any more than one extent, nor should it have included 610 * status beyond our request in that extent. However, it's easy 611 * enough to ignore the server's noncompliance without killing the 612 * connection; just ignore trailing extents, and clamp things to 613 * the length of our request. 614 */ 615 if (chunk->length > sizeof(context_id) + sizeof(*extent)) { 616 trace_nbd_parse_blockstatus_compliance("more than one extent"); 617 } 618 if (extent->length > orig_length) { 619 extent->length = orig_length; 620 trace_nbd_parse_blockstatus_compliance("extent length too large"); 621 } 622 623 return 0; 624 } 625 626 /* 627 * nbd_parse_error_payload 628 * on success @errp contains message describing nbd error reply 629 */ 630 static int nbd_parse_error_payload(NBDStructuredReplyChunk *chunk, 631 uint8_t *payload, int *request_ret, 632 Error **errp) 633 { 634 uint32_t error; 635 uint16_t message_size; 636 637 assert(chunk->type & (1 << 15)); 638 639 if (chunk->length < sizeof(error) + sizeof(message_size)) { 640 error_setg(errp, 641 "Protocol error: invalid payload for structured error"); 642 return -EINVAL; 643 } 644 645 error = nbd_errno_to_system_errno(payload_advance32(&payload)); 646 if (error == 0) { 647 error_setg(errp, "Protocol error: server sent structured error chunk " 648 "with error = 0"); 649 return -EINVAL; 650 } 651 652 *request_ret = -error; 653 message_size = payload_advance16(&payload); 654 655 if (message_size > chunk->length - sizeof(error) - sizeof(message_size)) { 656 error_setg(errp, "Protocol error: server sent structured error chunk " 657 "with incorrect message size"); 658 return -EINVAL; 659 } 660 661 /* TODO: Add a trace point to mention the server complaint */ 662 663 /* TODO handle ERROR_OFFSET */ 664 665 return 0; 666 } 667 668 static int nbd_co_receive_offset_data_payload(BDRVNBDState *s, 669 uint64_t orig_offset, 670 QEMUIOVector *qiov, Error **errp) 671 { 672 QEMUIOVector sub_qiov; 673 uint64_t offset; 674 size_t data_size; 675 int ret; 676 NBDStructuredReplyChunk *chunk = &s->reply.structured; 677 678 assert(nbd_reply_is_structured(&s->reply)); 679 680 /* The NBD spec requires at least one byte of payload */ 681 if (chunk->length <= sizeof(offset)) { 682 error_setg(errp, "Protocol error: invalid payload for " 683 "NBD_REPLY_TYPE_OFFSET_DATA"); 684 return -EINVAL; 685 } 686 687 if (nbd_read64(s->ioc, &offset, "OFFSET_DATA offset", errp) < 0) { 688 return -EIO; 689 } 690 691 data_size = chunk->length - sizeof(offset); 692 assert(data_size); 693 if (offset < orig_offset || data_size > qiov->size || 694 offset > orig_offset + qiov->size - data_size) { 695 error_setg(errp, "Protocol error: server sent chunk exceeding requested" 696 " region"); 697 return -EINVAL; 698 } 699 if (s->info.min_block && !QEMU_IS_ALIGNED(data_size, s->info.min_block)) { 700 trace_nbd_structured_read_compliance("data"); 701 } 702 703 qemu_iovec_init(&sub_qiov, qiov->niov); 704 qemu_iovec_concat(&sub_qiov, qiov, offset - orig_offset, data_size); 705 ret = qio_channel_readv_all(s->ioc, sub_qiov.iov, sub_qiov.niov, errp); 706 qemu_iovec_destroy(&sub_qiov); 707 708 return ret < 0 ? -EIO : 0; 709 } 710 711 #define NBD_MAX_MALLOC_PAYLOAD 1000 712 static coroutine_fn int nbd_co_receive_structured_payload( 713 BDRVNBDState *s, void **payload, Error **errp) 714 { 715 int ret; 716 uint32_t len; 717 718 assert(nbd_reply_is_structured(&s->reply)); 719 720 len = s->reply.structured.length; 721 722 if (len == 0) { 723 return 0; 724 } 725 726 if (payload == NULL) { 727 error_setg(errp, "Unexpected structured payload"); 728 return -EINVAL; 729 } 730 731 if (len > NBD_MAX_MALLOC_PAYLOAD) { 732 error_setg(errp, "Payload too large"); 733 return -EINVAL; 734 } 735 736 *payload = g_new(char, len); 737 ret = nbd_read(s->ioc, *payload, len, "structured payload", errp); 738 if (ret < 0) { 739 g_free(*payload); 740 *payload = NULL; 741 return ret; 742 } 743 744 return 0; 745 } 746 747 /* 748 * nbd_co_do_receive_one_chunk 749 * for simple reply: 750 * set request_ret to received reply error 751 * if qiov is not NULL: read payload to @qiov 752 * for structured reply chunk: 753 * if error chunk: read payload, set @request_ret, do not set @payload 754 * else if offset_data chunk: read payload data to @qiov, do not set @payload 755 * else: read payload to @payload 756 * 757 * If function fails, @errp contains corresponding error message, and the 758 * connection with the server is suspect. If it returns 0, then the 759 * transaction succeeded (although @request_ret may be a negative errno 760 * corresponding to the server's error reply), and errp is unchanged. 761 */ 762 static coroutine_fn int nbd_co_do_receive_one_chunk( 763 BDRVNBDState *s, uint64_t handle, bool only_structured, 764 int *request_ret, QEMUIOVector *qiov, void **payload, Error **errp) 765 { 766 int ret; 767 int i = HANDLE_TO_INDEX(s, handle); 768 void *local_payload = NULL; 769 NBDStructuredReplyChunk *chunk; 770 771 if (payload) { 772 *payload = NULL; 773 } 774 *request_ret = 0; 775 776 /* Wait until we're woken up by nbd_connection_entry. */ 777 s->requests[i].receiving = true; 778 qemu_coroutine_yield(); 779 s->requests[i].receiving = false; 780 if (s->state != NBD_CLIENT_CONNECTED) { 781 error_setg(errp, "Connection closed"); 782 return -EIO; 783 } 784 assert(s->ioc); 785 786 assert(s->reply.handle == handle); 787 788 if (nbd_reply_is_simple(&s->reply)) { 789 if (only_structured) { 790 error_setg(errp, "Protocol error: simple reply when structured " 791 "reply chunk was expected"); 792 return -EINVAL; 793 } 794 795 *request_ret = -nbd_errno_to_system_errno(s->reply.simple.error); 796 if (*request_ret < 0 || !qiov) { 797 return 0; 798 } 799 800 return qio_channel_readv_all(s->ioc, qiov->iov, qiov->niov, 801 errp) < 0 ? -EIO : 0; 802 } 803 804 /* handle structured reply chunk */ 805 assert(s->info.structured_reply); 806 chunk = &s->reply.structured; 807 808 if (chunk->type == NBD_REPLY_TYPE_NONE) { 809 if (!(chunk->flags & NBD_REPLY_FLAG_DONE)) { 810 error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk without" 811 " NBD_REPLY_FLAG_DONE flag set"); 812 return -EINVAL; 813 } 814 if (chunk->length) { 815 error_setg(errp, "Protocol error: NBD_REPLY_TYPE_NONE chunk with" 816 " nonzero length"); 817 return -EINVAL; 818 } 819 return 0; 820 } 821 822 if (chunk->type == NBD_REPLY_TYPE_OFFSET_DATA) { 823 if (!qiov) { 824 error_setg(errp, "Unexpected NBD_REPLY_TYPE_OFFSET_DATA chunk"); 825 return -EINVAL; 826 } 827 828 return nbd_co_receive_offset_data_payload(s, s->requests[i].offset, 829 qiov, errp); 830 } 831 832 if (nbd_reply_type_is_error(chunk->type)) { 833 payload = &local_payload; 834 } 835 836 ret = nbd_co_receive_structured_payload(s, payload, errp); 837 if (ret < 0) { 838 return ret; 839 } 840 841 if (nbd_reply_type_is_error(chunk->type)) { 842 ret = nbd_parse_error_payload(chunk, local_payload, request_ret, errp); 843 g_free(local_payload); 844 return ret; 845 } 846 847 return 0; 848 } 849 850 /* 851 * nbd_co_receive_one_chunk 852 * Read reply, wake up connection_co and set s->quit if needed. 853 * Return value is a fatal error code or normal nbd reply error code 854 */ 855 static coroutine_fn int nbd_co_receive_one_chunk( 856 BDRVNBDState *s, uint64_t handle, bool only_structured, 857 int *request_ret, QEMUIOVector *qiov, NBDReply *reply, void **payload, 858 Error **errp) 859 { 860 int ret = nbd_co_do_receive_one_chunk(s, handle, only_structured, 861 request_ret, qiov, payload, errp); 862 863 if (ret < 0) { 864 memset(reply, 0, sizeof(*reply)); 865 nbd_channel_error(s, ret); 866 } else { 867 /* For assert at loop start in nbd_connection_entry */ 868 *reply = s->reply; 869 } 870 s->reply.handle = 0; 871 872 if (s->connection_co && !s->wait_in_flight) { 873 /* 874 * We must check s->wait_in_flight, because we may entered by 875 * nbd_recv_coroutines_wake_all(), in this case we should not 876 * wake connection_co here, it will woken by last request. 877 */ 878 aio_co_wake(s->connection_co); 879 } 880 881 return ret; 882 } 883 884 typedef struct NBDReplyChunkIter { 885 int ret; 886 int request_ret; 887 Error *err; 888 bool done, only_structured; 889 } NBDReplyChunkIter; 890 891 static void nbd_iter_channel_error(NBDReplyChunkIter *iter, 892 int ret, Error **local_err) 893 { 894 assert(local_err && *local_err); 895 assert(ret < 0); 896 897 if (!iter->ret) { 898 iter->ret = ret; 899 error_propagate(&iter->err, *local_err); 900 } else { 901 error_free(*local_err); 902 } 903 904 *local_err = NULL; 905 } 906 907 static void nbd_iter_request_error(NBDReplyChunkIter *iter, int ret) 908 { 909 assert(ret < 0); 910 911 if (!iter->request_ret) { 912 iter->request_ret = ret; 913 } 914 } 915 916 /* 917 * NBD_FOREACH_REPLY_CHUNK 918 * The pointer stored in @payload requires g_free() to free it. 919 */ 920 #define NBD_FOREACH_REPLY_CHUNK(s, iter, handle, structured, \ 921 qiov, reply, payload) \ 922 for (iter = (NBDReplyChunkIter) { .only_structured = structured }; \ 923 nbd_reply_chunk_iter_receive(s, &iter, handle, qiov, reply, payload);) 924 925 /* 926 * nbd_reply_chunk_iter_receive 927 * The pointer stored in @payload requires g_free() to free it. 928 */ 929 static bool nbd_reply_chunk_iter_receive(BDRVNBDState *s, 930 NBDReplyChunkIter *iter, 931 uint64_t handle, 932 QEMUIOVector *qiov, NBDReply *reply, 933 void **payload) 934 { 935 int ret, request_ret; 936 NBDReply local_reply; 937 NBDStructuredReplyChunk *chunk; 938 Error *local_err = NULL; 939 if (s->state != NBD_CLIENT_CONNECTED) { 940 error_setg(&local_err, "Connection closed"); 941 nbd_iter_channel_error(iter, -EIO, &local_err); 942 goto break_loop; 943 } 944 945 if (iter->done) { 946 /* Previous iteration was last. */ 947 goto break_loop; 948 } 949 950 if (reply == NULL) { 951 reply = &local_reply; 952 } 953 954 ret = nbd_co_receive_one_chunk(s, handle, iter->only_structured, 955 &request_ret, qiov, reply, payload, 956 &local_err); 957 if (ret < 0) { 958 nbd_iter_channel_error(iter, ret, &local_err); 959 } else if (request_ret < 0) { 960 nbd_iter_request_error(iter, request_ret); 961 } 962 963 /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */ 964 if (nbd_reply_is_simple(reply) || s->state != NBD_CLIENT_CONNECTED) { 965 goto break_loop; 966 } 967 968 chunk = &reply->structured; 969 iter->only_structured = true; 970 971 if (chunk->type == NBD_REPLY_TYPE_NONE) { 972 /* NBD_REPLY_FLAG_DONE is already checked in nbd_co_receive_one_chunk */ 973 assert(chunk->flags & NBD_REPLY_FLAG_DONE); 974 goto break_loop; 975 } 976 977 if (chunk->flags & NBD_REPLY_FLAG_DONE) { 978 /* This iteration is last. */ 979 iter->done = true; 980 } 981 982 /* Execute the loop body */ 983 return true; 984 985 break_loop: 986 s->requests[HANDLE_TO_INDEX(s, handle)].coroutine = NULL; 987 988 qemu_co_mutex_lock(&s->send_mutex); 989 s->in_flight--; 990 if (s->in_flight == 0 && s->wait_in_flight) { 991 aio_co_wake(s->connection_co); 992 } else { 993 qemu_co_queue_next(&s->free_sema); 994 } 995 qemu_co_mutex_unlock(&s->send_mutex); 996 997 return false; 998 } 999 1000 static int nbd_co_receive_return_code(BDRVNBDState *s, uint64_t handle, 1001 int *request_ret, Error **errp) 1002 { 1003 NBDReplyChunkIter iter; 1004 1005 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, NULL, NULL) { 1006 /* nbd_reply_chunk_iter_receive does all the work */ 1007 } 1008 1009 error_propagate(errp, iter.err); 1010 *request_ret = iter.request_ret; 1011 return iter.ret; 1012 } 1013 1014 static int nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t handle, 1015 uint64_t offset, QEMUIOVector *qiov, 1016 int *request_ret, Error **errp) 1017 { 1018 NBDReplyChunkIter iter; 1019 NBDReply reply; 1020 void *payload = NULL; 1021 Error *local_err = NULL; 1022 1023 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, s->info.structured_reply, 1024 qiov, &reply, &payload) 1025 { 1026 int ret; 1027 NBDStructuredReplyChunk *chunk = &reply.structured; 1028 1029 assert(nbd_reply_is_structured(&reply)); 1030 1031 switch (chunk->type) { 1032 case NBD_REPLY_TYPE_OFFSET_DATA: 1033 /* 1034 * special cased in nbd_co_receive_one_chunk, data is already 1035 * in qiov 1036 */ 1037 break; 1038 case NBD_REPLY_TYPE_OFFSET_HOLE: 1039 ret = nbd_parse_offset_hole_payload(s, &reply.structured, payload, 1040 offset, qiov, &local_err); 1041 if (ret < 0) { 1042 nbd_channel_error(s, ret); 1043 nbd_iter_channel_error(&iter, ret, &local_err); 1044 } 1045 break; 1046 default: 1047 if (!nbd_reply_type_is_error(chunk->type)) { 1048 /* not allowed reply type */ 1049 nbd_channel_error(s, -EINVAL); 1050 error_setg(&local_err, 1051 "Unexpected reply type: %d (%s) for CMD_READ", 1052 chunk->type, nbd_reply_type_lookup(chunk->type)); 1053 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1054 } 1055 } 1056 1057 g_free(payload); 1058 payload = NULL; 1059 } 1060 1061 error_propagate(errp, iter.err); 1062 *request_ret = iter.request_ret; 1063 return iter.ret; 1064 } 1065 1066 static int nbd_co_receive_blockstatus_reply(BDRVNBDState *s, 1067 uint64_t handle, uint64_t length, 1068 NBDExtent *extent, 1069 int *request_ret, Error **errp) 1070 { 1071 NBDReplyChunkIter iter; 1072 NBDReply reply; 1073 void *payload = NULL; 1074 Error *local_err = NULL; 1075 bool received = false; 1076 1077 assert(!extent->length); 1078 NBD_FOREACH_REPLY_CHUNK(s, iter, handle, false, NULL, &reply, &payload) { 1079 int ret; 1080 NBDStructuredReplyChunk *chunk = &reply.structured; 1081 1082 assert(nbd_reply_is_structured(&reply)); 1083 1084 switch (chunk->type) { 1085 case NBD_REPLY_TYPE_BLOCK_STATUS: 1086 if (received) { 1087 nbd_channel_error(s, -EINVAL); 1088 error_setg(&local_err, "Several BLOCK_STATUS chunks in reply"); 1089 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1090 } 1091 received = true; 1092 1093 ret = nbd_parse_blockstatus_payload(s, &reply.structured, 1094 payload, length, extent, 1095 &local_err); 1096 if (ret < 0) { 1097 nbd_channel_error(s, ret); 1098 nbd_iter_channel_error(&iter, ret, &local_err); 1099 } 1100 break; 1101 default: 1102 if (!nbd_reply_type_is_error(chunk->type)) { 1103 nbd_channel_error(s, -EINVAL); 1104 error_setg(&local_err, 1105 "Unexpected reply type: %d (%s) " 1106 "for CMD_BLOCK_STATUS", 1107 chunk->type, nbd_reply_type_lookup(chunk->type)); 1108 nbd_iter_channel_error(&iter, -EINVAL, &local_err); 1109 } 1110 } 1111 1112 g_free(payload); 1113 payload = NULL; 1114 } 1115 1116 if (!extent->length && !iter.request_ret) { 1117 error_setg(&local_err, "Server did not reply with any status extents"); 1118 nbd_iter_channel_error(&iter, -EIO, &local_err); 1119 } 1120 1121 error_propagate(errp, iter.err); 1122 *request_ret = iter.request_ret; 1123 return iter.ret; 1124 } 1125 1126 static int nbd_co_request(BlockDriverState *bs, NBDRequest *request, 1127 QEMUIOVector *write_qiov) 1128 { 1129 int ret, request_ret; 1130 Error *local_err = NULL; 1131 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1132 1133 assert(request->type != NBD_CMD_READ); 1134 if (write_qiov) { 1135 assert(request->type == NBD_CMD_WRITE); 1136 assert(request->len == iov_size(write_qiov->iov, write_qiov->niov)); 1137 } else { 1138 assert(request->type != NBD_CMD_WRITE); 1139 } 1140 1141 do { 1142 ret = nbd_co_send_request(bs, request, write_qiov); 1143 if (ret < 0) { 1144 continue; 1145 } 1146 1147 ret = nbd_co_receive_return_code(s, request->handle, 1148 &request_ret, &local_err); 1149 if (local_err) { 1150 trace_nbd_co_request_fail(request->from, request->len, 1151 request->handle, request->flags, 1152 request->type, 1153 nbd_cmd_lookup(request->type), 1154 ret, error_get_pretty(local_err)); 1155 error_free(local_err); 1156 local_err = NULL; 1157 } 1158 } while (ret < 0 && nbd_client_connecting_wait(s)); 1159 1160 return ret ? ret : request_ret; 1161 } 1162 1163 static int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, 1164 uint64_t bytes, QEMUIOVector *qiov, int flags) 1165 { 1166 int ret, request_ret; 1167 Error *local_err = NULL; 1168 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1169 NBDRequest request = { 1170 .type = NBD_CMD_READ, 1171 .from = offset, 1172 .len = bytes, 1173 }; 1174 1175 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1176 assert(!flags); 1177 1178 if (!bytes) { 1179 return 0; 1180 } 1181 /* 1182 * Work around the fact that the block layer doesn't do 1183 * byte-accurate sizing yet - if the read exceeds the server's 1184 * advertised size because the block layer rounded size up, then 1185 * truncate the request to the server and tail-pad with zero. 1186 */ 1187 if (offset >= s->info.size) { 1188 assert(bytes < BDRV_SECTOR_SIZE); 1189 qemu_iovec_memset(qiov, 0, 0, bytes); 1190 return 0; 1191 } 1192 if (offset + bytes > s->info.size) { 1193 uint64_t slop = offset + bytes - s->info.size; 1194 1195 assert(slop < BDRV_SECTOR_SIZE); 1196 qemu_iovec_memset(qiov, bytes - slop, 0, slop); 1197 request.len -= slop; 1198 } 1199 1200 do { 1201 ret = nbd_co_send_request(bs, &request, NULL); 1202 if (ret < 0) { 1203 continue; 1204 } 1205 1206 ret = nbd_co_receive_cmdread_reply(s, request.handle, offset, qiov, 1207 &request_ret, &local_err); 1208 if (local_err) { 1209 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1210 request.flags, request.type, 1211 nbd_cmd_lookup(request.type), 1212 ret, error_get_pretty(local_err)); 1213 error_free(local_err); 1214 local_err = NULL; 1215 } 1216 } while (ret < 0 && nbd_client_connecting_wait(s)); 1217 1218 return ret ? ret : request_ret; 1219 } 1220 1221 static int nbd_client_co_pwritev(BlockDriverState *bs, uint64_t offset, 1222 uint64_t bytes, QEMUIOVector *qiov, int flags) 1223 { 1224 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1225 NBDRequest request = { 1226 .type = NBD_CMD_WRITE, 1227 .from = offset, 1228 .len = bytes, 1229 }; 1230 1231 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1232 if (flags & BDRV_REQ_FUA) { 1233 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1234 request.flags |= NBD_CMD_FLAG_FUA; 1235 } 1236 1237 assert(bytes <= NBD_MAX_BUFFER_SIZE); 1238 1239 if (!bytes) { 1240 return 0; 1241 } 1242 return nbd_co_request(bs, &request, qiov); 1243 } 1244 1245 static int nbd_client_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, 1246 int bytes, BdrvRequestFlags flags) 1247 { 1248 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1249 NBDRequest request = { 1250 .type = NBD_CMD_WRITE_ZEROES, 1251 .from = offset, 1252 .len = bytes, 1253 }; 1254 1255 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1256 if (!(s->info.flags & NBD_FLAG_SEND_WRITE_ZEROES)) { 1257 return -ENOTSUP; 1258 } 1259 1260 if (flags & BDRV_REQ_FUA) { 1261 assert(s->info.flags & NBD_FLAG_SEND_FUA); 1262 request.flags |= NBD_CMD_FLAG_FUA; 1263 } 1264 if (!(flags & BDRV_REQ_MAY_UNMAP)) { 1265 request.flags |= NBD_CMD_FLAG_NO_HOLE; 1266 } 1267 if (flags & BDRV_REQ_NO_FALLBACK) { 1268 assert(s->info.flags & NBD_FLAG_SEND_FAST_ZERO); 1269 request.flags |= NBD_CMD_FLAG_FAST_ZERO; 1270 } 1271 1272 if (!bytes) { 1273 return 0; 1274 } 1275 return nbd_co_request(bs, &request, NULL); 1276 } 1277 1278 static int nbd_client_co_flush(BlockDriverState *bs) 1279 { 1280 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1281 NBDRequest request = { .type = NBD_CMD_FLUSH }; 1282 1283 if (!(s->info.flags & NBD_FLAG_SEND_FLUSH)) { 1284 return 0; 1285 } 1286 1287 request.from = 0; 1288 request.len = 0; 1289 1290 return nbd_co_request(bs, &request, NULL); 1291 } 1292 1293 static int nbd_client_co_pdiscard(BlockDriverState *bs, int64_t offset, 1294 int bytes) 1295 { 1296 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1297 NBDRequest request = { 1298 .type = NBD_CMD_TRIM, 1299 .from = offset, 1300 .len = bytes, 1301 }; 1302 1303 assert(!(s->info.flags & NBD_FLAG_READ_ONLY)); 1304 if (!(s->info.flags & NBD_FLAG_SEND_TRIM) || !bytes) { 1305 return 0; 1306 } 1307 1308 return nbd_co_request(bs, &request, NULL); 1309 } 1310 1311 static int coroutine_fn nbd_client_co_block_status( 1312 BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes, 1313 int64_t *pnum, int64_t *map, BlockDriverState **file) 1314 { 1315 int ret, request_ret; 1316 NBDExtent extent = { 0 }; 1317 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1318 Error *local_err = NULL; 1319 1320 NBDRequest request = { 1321 .type = NBD_CMD_BLOCK_STATUS, 1322 .from = offset, 1323 .len = MIN(MIN_NON_ZERO(QEMU_ALIGN_DOWN(INT_MAX, 1324 bs->bl.request_alignment), 1325 s->info.max_block), 1326 MIN(bytes, s->info.size - offset)), 1327 .flags = NBD_CMD_FLAG_REQ_ONE, 1328 }; 1329 1330 if (!s->info.base_allocation) { 1331 *pnum = bytes; 1332 *map = offset; 1333 *file = bs; 1334 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1335 } 1336 1337 /* 1338 * Work around the fact that the block layer doesn't do 1339 * byte-accurate sizing yet - if the status request exceeds the 1340 * server's advertised size because the block layer rounded size 1341 * up, we truncated the request to the server (above), or are 1342 * called on just the hole. 1343 */ 1344 if (offset >= s->info.size) { 1345 *pnum = bytes; 1346 assert(bytes < BDRV_SECTOR_SIZE); 1347 /* Intentionally don't report offset_valid for the hole */ 1348 return BDRV_BLOCK_ZERO; 1349 } 1350 1351 if (s->info.min_block) { 1352 assert(QEMU_IS_ALIGNED(request.len, s->info.min_block)); 1353 } 1354 do { 1355 ret = nbd_co_send_request(bs, &request, NULL); 1356 if (ret < 0) { 1357 continue; 1358 } 1359 1360 ret = nbd_co_receive_blockstatus_reply(s, request.handle, bytes, 1361 &extent, &request_ret, 1362 &local_err); 1363 if (local_err) { 1364 trace_nbd_co_request_fail(request.from, request.len, request.handle, 1365 request.flags, request.type, 1366 nbd_cmd_lookup(request.type), 1367 ret, error_get_pretty(local_err)); 1368 error_free(local_err); 1369 local_err = NULL; 1370 } 1371 } while (ret < 0 && nbd_client_connecting_wait(s)); 1372 1373 if (ret < 0 || request_ret < 0) { 1374 return ret ? ret : request_ret; 1375 } 1376 1377 assert(extent.length); 1378 *pnum = extent.length; 1379 *map = offset; 1380 *file = bs; 1381 return (extent.flags & NBD_STATE_HOLE ? 0 : BDRV_BLOCK_DATA) | 1382 (extent.flags & NBD_STATE_ZERO ? BDRV_BLOCK_ZERO : 0) | 1383 BDRV_BLOCK_OFFSET_VALID; 1384 } 1385 1386 static int nbd_client_reopen_prepare(BDRVReopenState *state, 1387 BlockReopenQueue *queue, Error **errp) 1388 { 1389 BDRVNBDState *s = (BDRVNBDState *)state->bs->opaque; 1390 1391 if ((state->flags & BDRV_O_RDWR) && (s->info.flags & NBD_FLAG_READ_ONLY)) { 1392 error_setg(errp, "Can't reopen read-only NBD mount as read/write"); 1393 return -EACCES; 1394 } 1395 return 0; 1396 } 1397 1398 static void nbd_client_close(BlockDriverState *bs) 1399 { 1400 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1401 NBDRequest request = { .type = NBD_CMD_DISC }; 1402 1403 if (s->ioc) { 1404 nbd_send_request(s->ioc, &request); 1405 } 1406 1407 nbd_teardown_connection(bs); 1408 } 1409 1410 static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, 1411 Error **errp) 1412 { 1413 QIOChannelSocket *sioc; 1414 Error *local_err = NULL; 1415 1416 sioc = qio_channel_socket_new(); 1417 qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client"); 1418 1419 qio_channel_socket_connect_sync(sioc, saddr, &local_err); 1420 if (local_err) { 1421 object_unref(OBJECT(sioc)); 1422 error_propagate(errp, local_err); 1423 return NULL; 1424 } 1425 1426 qio_channel_set_delay(QIO_CHANNEL(sioc), false); 1427 1428 return sioc; 1429 } 1430 1431 static int nbd_client_connect(BlockDriverState *bs, Error **errp) 1432 { 1433 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1434 AioContext *aio_context = bdrv_get_aio_context(bs); 1435 int ret; 1436 1437 /* 1438 * establish TCP connection, return error if it fails 1439 * TODO: Configurable retry-until-timeout behaviour. 1440 */ 1441 QIOChannelSocket *sioc = nbd_establish_connection(s->saddr, errp); 1442 1443 if (!sioc) { 1444 return -ECONNREFUSED; 1445 } 1446 1447 /* NBD handshake */ 1448 trace_nbd_client_connect(s->export); 1449 qio_channel_set_blocking(QIO_CHANNEL(sioc), false, NULL); 1450 qio_channel_attach_aio_context(QIO_CHANNEL(sioc), aio_context); 1451 1452 s->info.request_sizes = true; 1453 s->info.structured_reply = true; 1454 s->info.base_allocation = true; 1455 s->info.x_dirty_bitmap = g_strdup(s->x_dirty_bitmap); 1456 s->info.name = g_strdup(s->export ?: ""); 1457 ret = nbd_receive_negotiate(aio_context, QIO_CHANNEL(sioc), s->tlscreds, 1458 s->hostname, &s->ioc, &s->info, errp); 1459 g_free(s->info.x_dirty_bitmap); 1460 g_free(s->info.name); 1461 if (ret < 0) { 1462 object_unref(OBJECT(sioc)); 1463 return ret; 1464 } 1465 if (s->x_dirty_bitmap && !s->info.base_allocation) { 1466 error_setg(errp, "requested x-dirty-bitmap %s not found", 1467 s->x_dirty_bitmap); 1468 ret = -EINVAL; 1469 goto fail; 1470 } 1471 if (s->info.flags & NBD_FLAG_READ_ONLY) { 1472 ret = bdrv_apply_auto_read_only(bs, "NBD export is read-only", errp); 1473 if (ret < 0) { 1474 goto fail; 1475 } 1476 } 1477 if (s->info.flags & NBD_FLAG_SEND_FUA) { 1478 bs->supported_write_flags = BDRV_REQ_FUA; 1479 bs->supported_zero_flags |= BDRV_REQ_FUA; 1480 } 1481 if (s->info.flags & NBD_FLAG_SEND_WRITE_ZEROES) { 1482 bs->supported_zero_flags |= BDRV_REQ_MAY_UNMAP; 1483 if (s->info.flags & NBD_FLAG_SEND_FAST_ZERO) { 1484 bs->supported_zero_flags |= BDRV_REQ_NO_FALLBACK; 1485 } 1486 } 1487 1488 s->sioc = sioc; 1489 1490 if (!s->ioc) { 1491 s->ioc = QIO_CHANNEL(sioc); 1492 object_ref(OBJECT(s->ioc)); 1493 } 1494 1495 trace_nbd_client_connect_success(s->export); 1496 1497 return 0; 1498 1499 fail: 1500 /* 1501 * We have connected, but must fail for other reasons. 1502 * Send NBD_CMD_DISC as a courtesy to the server. 1503 */ 1504 { 1505 NBDRequest request = { .type = NBD_CMD_DISC }; 1506 1507 nbd_send_request(s->ioc ?: QIO_CHANNEL(sioc), &request); 1508 1509 object_unref(OBJECT(sioc)); 1510 1511 return ret; 1512 } 1513 } 1514 1515 /* 1516 * Parse nbd_open options 1517 */ 1518 1519 static int nbd_parse_uri(const char *filename, QDict *options) 1520 { 1521 URI *uri; 1522 const char *p; 1523 QueryParams *qp = NULL; 1524 int ret = 0; 1525 bool is_unix; 1526 1527 uri = uri_parse(filename); 1528 if (!uri) { 1529 return -EINVAL; 1530 } 1531 1532 /* transport */ 1533 if (!g_strcmp0(uri->scheme, "nbd")) { 1534 is_unix = false; 1535 } else if (!g_strcmp0(uri->scheme, "nbd+tcp")) { 1536 is_unix = false; 1537 } else if (!g_strcmp0(uri->scheme, "nbd+unix")) { 1538 is_unix = true; 1539 } else { 1540 ret = -EINVAL; 1541 goto out; 1542 } 1543 1544 p = uri->path ? uri->path : ""; 1545 if (p[0] == '/') { 1546 p++; 1547 } 1548 if (p[0]) { 1549 qdict_put_str(options, "export", p); 1550 } 1551 1552 qp = query_params_parse(uri->query); 1553 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 1554 ret = -EINVAL; 1555 goto out; 1556 } 1557 1558 if (is_unix) { 1559 /* nbd+unix:///export?socket=path */ 1560 if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { 1561 ret = -EINVAL; 1562 goto out; 1563 } 1564 qdict_put_str(options, "server.type", "unix"); 1565 qdict_put_str(options, "server.path", qp->p[0].value); 1566 } else { 1567 QString *host; 1568 char *port_str; 1569 1570 /* nbd[+tcp]://host[:port]/export */ 1571 if (!uri->server) { 1572 ret = -EINVAL; 1573 goto out; 1574 } 1575 1576 /* strip braces from literal IPv6 address */ 1577 if (uri->server[0] == '[') { 1578 host = qstring_from_substr(uri->server, 1, 1579 strlen(uri->server) - 1); 1580 } else { 1581 host = qstring_from_str(uri->server); 1582 } 1583 1584 qdict_put_str(options, "server.type", "inet"); 1585 qdict_put(options, "server.host", host); 1586 1587 port_str = g_strdup_printf("%d", uri->port ?: NBD_DEFAULT_PORT); 1588 qdict_put_str(options, "server.port", port_str); 1589 g_free(port_str); 1590 } 1591 1592 out: 1593 if (qp) { 1594 query_params_free(qp); 1595 } 1596 uri_free(uri); 1597 return ret; 1598 } 1599 1600 static bool nbd_has_filename_options_conflict(QDict *options, Error **errp) 1601 { 1602 const QDictEntry *e; 1603 1604 for (e = qdict_first(options); e; e = qdict_next(options, e)) { 1605 if (!strcmp(e->key, "host") || 1606 !strcmp(e->key, "port") || 1607 !strcmp(e->key, "path") || 1608 !strcmp(e->key, "export") || 1609 strstart(e->key, "server.", NULL)) 1610 { 1611 error_setg(errp, "Option '%s' cannot be used with a file name", 1612 e->key); 1613 return true; 1614 } 1615 } 1616 1617 return false; 1618 } 1619 1620 static void nbd_parse_filename(const char *filename, QDict *options, 1621 Error **errp) 1622 { 1623 g_autofree char *file = NULL; 1624 char *export_name; 1625 const char *host_spec; 1626 const char *unixpath; 1627 1628 if (nbd_has_filename_options_conflict(options, errp)) { 1629 return; 1630 } 1631 1632 if (strstr(filename, "://")) { 1633 int ret = nbd_parse_uri(filename, options); 1634 if (ret < 0) { 1635 error_setg(errp, "No valid URL specified"); 1636 } 1637 return; 1638 } 1639 1640 file = g_strdup(filename); 1641 1642 export_name = strstr(file, EN_OPTSTR); 1643 if (export_name) { 1644 if (export_name[strlen(EN_OPTSTR)] == 0) { 1645 return; 1646 } 1647 export_name[0] = 0; /* truncate 'file' */ 1648 export_name += strlen(EN_OPTSTR); 1649 1650 qdict_put_str(options, "export", export_name); 1651 } 1652 1653 /* extract the host_spec - fail if it's not nbd:... */ 1654 if (!strstart(file, "nbd:", &host_spec)) { 1655 error_setg(errp, "File name string for NBD must start with 'nbd:'"); 1656 return; 1657 } 1658 1659 if (!*host_spec) { 1660 return; 1661 } 1662 1663 /* are we a UNIX or TCP socket? */ 1664 if (strstart(host_spec, "unix:", &unixpath)) { 1665 qdict_put_str(options, "server.type", "unix"); 1666 qdict_put_str(options, "server.path", unixpath); 1667 } else { 1668 InetSocketAddress *addr = g_new(InetSocketAddress, 1); 1669 1670 if (inet_parse(addr, host_spec, errp)) { 1671 goto out_inet; 1672 } 1673 1674 qdict_put_str(options, "server.type", "inet"); 1675 qdict_put_str(options, "server.host", addr->host); 1676 qdict_put_str(options, "server.port", addr->port); 1677 out_inet: 1678 qapi_free_InetSocketAddress(addr); 1679 } 1680 } 1681 1682 static bool nbd_process_legacy_socket_options(QDict *output_options, 1683 QemuOpts *legacy_opts, 1684 Error **errp) 1685 { 1686 const char *path = qemu_opt_get(legacy_opts, "path"); 1687 const char *host = qemu_opt_get(legacy_opts, "host"); 1688 const char *port = qemu_opt_get(legacy_opts, "port"); 1689 const QDictEntry *e; 1690 1691 if (!path && !host && !port) { 1692 return true; 1693 } 1694 1695 for (e = qdict_first(output_options); e; e = qdict_next(output_options, e)) 1696 { 1697 if (strstart(e->key, "server.", NULL)) { 1698 error_setg(errp, "Cannot use 'server' and path/host/port at the " 1699 "same time"); 1700 return false; 1701 } 1702 } 1703 1704 if (path && host) { 1705 error_setg(errp, "path and host may not be used at the same time"); 1706 return false; 1707 } else if (path) { 1708 if (port) { 1709 error_setg(errp, "port may not be used without host"); 1710 return false; 1711 } 1712 1713 qdict_put_str(output_options, "server.type", "unix"); 1714 qdict_put_str(output_options, "server.path", path); 1715 } else if (host) { 1716 qdict_put_str(output_options, "server.type", "inet"); 1717 qdict_put_str(output_options, "server.host", host); 1718 qdict_put_str(output_options, "server.port", 1719 port ?: stringify(NBD_DEFAULT_PORT)); 1720 } 1721 1722 return true; 1723 } 1724 1725 static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, 1726 Error **errp) 1727 { 1728 SocketAddress *saddr = NULL; 1729 QDict *addr = NULL; 1730 Visitor *iv = NULL; 1731 Error *local_err = NULL; 1732 1733 qdict_extract_subqdict(options, &addr, "server."); 1734 if (!qdict_size(addr)) { 1735 error_setg(errp, "NBD server address missing"); 1736 goto done; 1737 } 1738 1739 iv = qobject_input_visitor_new_flat_confused(addr, errp); 1740 if (!iv) { 1741 goto done; 1742 } 1743 1744 visit_type_SocketAddress(iv, NULL, &saddr, &local_err); 1745 if (local_err) { 1746 error_propagate(errp, local_err); 1747 goto done; 1748 } 1749 1750 done: 1751 qobject_unref(addr); 1752 visit_free(iv); 1753 return saddr; 1754 } 1755 1756 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 1757 { 1758 Object *obj; 1759 QCryptoTLSCreds *creds; 1760 1761 obj = object_resolve_path_component( 1762 object_get_objects_root(), id); 1763 if (!obj) { 1764 error_setg(errp, "No TLS credentials with id '%s'", 1765 id); 1766 return NULL; 1767 } 1768 creds = (QCryptoTLSCreds *) 1769 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 1770 if (!creds) { 1771 error_setg(errp, "Object with id '%s' is not TLS credentials", 1772 id); 1773 return NULL; 1774 } 1775 1776 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 1777 error_setg(errp, 1778 "Expecting TLS credentials with a client endpoint"); 1779 return NULL; 1780 } 1781 object_ref(obj); 1782 return creds; 1783 } 1784 1785 1786 static QemuOptsList nbd_runtime_opts = { 1787 .name = "nbd", 1788 .head = QTAILQ_HEAD_INITIALIZER(nbd_runtime_opts.head), 1789 .desc = { 1790 { 1791 .name = "host", 1792 .type = QEMU_OPT_STRING, 1793 .help = "TCP host to connect to", 1794 }, 1795 { 1796 .name = "port", 1797 .type = QEMU_OPT_STRING, 1798 .help = "TCP port to connect to", 1799 }, 1800 { 1801 .name = "path", 1802 .type = QEMU_OPT_STRING, 1803 .help = "Unix socket path to connect to", 1804 }, 1805 { 1806 .name = "export", 1807 .type = QEMU_OPT_STRING, 1808 .help = "Name of the NBD export to open", 1809 }, 1810 { 1811 .name = "tls-creds", 1812 .type = QEMU_OPT_STRING, 1813 .help = "ID of the TLS credentials to use", 1814 }, 1815 { 1816 .name = "x-dirty-bitmap", 1817 .type = QEMU_OPT_STRING, 1818 .help = "experimental: expose named dirty bitmap in place of " 1819 "block status", 1820 }, 1821 { 1822 .name = "reconnect-delay", 1823 .type = QEMU_OPT_NUMBER, 1824 .help = "On an unexpected disconnect, the nbd client tries to " 1825 "connect again until succeeding or encountering a serious " 1826 "error. During the first @reconnect-delay seconds, all " 1827 "requests are paused and will be rerun on a successful " 1828 "reconnect. After that time, any delayed requests and all " 1829 "future requests before a successful reconnect will " 1830 "immediately fail. Default 0", 1831 }, 1832 { /* end of list */ } 1833 }, 1834 }; 1835 1836 static int nbd_process_options(BlockDriverState *bs, QDict *options, 1837 Error **errp) 1838 { 1839 BDRVNBDState *s = bs->opaque; 1840 QemuOpts *opts; 1841 Error *local_err = NULL; 1842 int ret = -EINVAL; 1843 1844 opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort); 1845 qemu_opts_absorb_qdict(opts, options, &local_err); 1846 if (local_err) { 1847 error_propagate(errp, local_err); 1848 goto error; 1849 } 1850 1851 /* Translate @host, @port, and @path to a SocketAddress */ 1852 if (!nbd_process_legacy_socket_options(options, opts, errp)) { 1853 goto error; 1854 } 1855 1856 /* Pop the config into our state object. Exit if invalid. */ 1857 s->saddr = nbd_config(s, options, errp); 1858 if (!s->saddr) { 1859 goto error; 1860 } 1861 1862 s->export = g_strdup(qemu_opt_get(opts, "export")); 1863 if (s->export && strlen(s->export) > NBD_MAX_STRING_SIZE) { 1864 error_setg(errp, "export name too long to send to server"); 1865 goto error; 1866 } 1867 1868 s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds")); 1869 if (s->tlscredsid) { 1870 s->tlscreds = nbd_get_tls_creds(s->tlscredsid, errp); 1871 if (!s->tlscreds) { 1872 goto error; 1873 } 1874 1875 /* TODO SOCKET_ADDRESS_KIND_FD where fd has AF_INET or AF_INET6 */ 1876 if (s->saddr->type != SOCKET_ADDRESS_TYPE_INET) { 1877 error_setg(errp, "TLS only supported over IP sockets"); 1878 goto error; 1879 } 1880 s->hostname = s->saddr->u.inet.host; 1881 } 1882 1883 s->x_dirty_bitmap = g_strdup(qemu_opt_get(opts, "x-dirty-bitmap")); 1884 if (s->x_dirty_bitmap && strlen(s->x_dirty_bitmap) > NBD_MAX_STRING_SIZE) { 1885 error_setg(errp, "x-dirty-bitmap query too long to send to server"); 1886 goto error; 1887 } 1888 1889 s->reconnect_delay = qemu_opt_get_number(opts, "reconnect-delay", 0); 1890 1891 ret = 0; 1892 1893 error: 1894 if (ret < 0) { 1895 nbd_clear_bdrvstate(s); 1896 } 1897 qemu_opts_del(opts); 1898 return ret; 1899 } 1900 1901 static int nbd_open(BlockDriverState *bs, QDict *options, int flags, 1902 Error **errp) 1903 { 1904 int ret; 1905 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1906 1907 ret = nbd_process_options(bs, options, errp); 1908 if (ret < 0) { 1909 return ret; 1910 } 1911 1912 s->bs = bs; 1913 qemu_co_mutex_init(&s->send_mutex); 1914 qemu_co_queue_init(&s->free_sema); 1915 1916 ret = nbd_client_connect(bs, errp); 1917 if (ret < 0) { 1918 nbd_clear_bdrvstate(s); 1919 return ret; 1920 } 1921 /* successfully connected */ 1922 s->state = NBD_CLIENT_CONNECTED; 1923 1924 s->connection_co = qemu_coroutine_create(nbd_connection_entry, s); 1925 bdrv_inc_in_flight(bs); 1926 aio_co_schedule(bdrv_get_aio_context(bs), s->connection_co); 1927 1928 return 0; 1929 } 1930 1931 static int nbd_co_flush(BlockDriverState *bs) 1932 { 1933 return nbd_client_co_flush(bs); 1934 } 1935 1936 static void nbd_refresh_limits(BlockDriverState *bs, Error **errp) 1937 { 1938 BDRVNBDState *s = (BDRVNBDState *)bs->opaque; 1939 uint32_t min = s->info.min_block; 1940 uint32_t max = MIN_NON_ZERO(NBD_MAX_BUFFER_SIZE, s->info.max_block); 1941 1942 /* 1943 * If the server did not advertise an alignment: 1944 * - a size that is not sector-aligned implies that an alignment 1945 * of 1 can be used to access those tail bytes 1946 * - advertisement of block status requires an alignment of 1, so 1947 * that we don't violate block layer constraints that block 1948 * status is always aligned (as we can't control whether the 1949 * server will report sub-sector extents, such as a hole at EOF 1950 * on an unaligned POSIX file) 1951 * - otherwise, assume the server is so old that we are safer avoiding 1952 * sub-sector requests 1953 */ 1954 if (!min) { 1955 min = (!QEMU_IS_ALIGNED(s->info.size, BDRV_SECTOR_SIZE) || 1956 s->info.base_allocation) ? 1 : BDRV_SECTOR_SIZE; 1957 } 1958 1959 bs->bl.request_alignment = min; 1960 bs->bl.max_pdiscard = max; 1961 bs->bl.max_pwrite_zeroes = max; 1962 bs->bl.max_transfer = max; 1963 1964 if (s->info.opt_block && 1965 s->info.opt_block > bs->bl.opt_transfer) { 1966 bs->bl.opt_transfer = s->info.opt_block; 1967 } 1968 } 1969 1970 static void nbd_close(BlockDriverState *bs) 1971 { 1972 BDRVNBDState *s = bs->opaque; 1973 1974 nbd_client_close(bs); 1975 nbd_clear_bdrvstate(s); 1976 } 1977 1978 static int64_t nbd_getlength(BlockDriverState *bs) 1979 { 1980 BDRVNBDState *s = bs->opaque; 1981 1982 return s->info.size; 1983 } 1984 1985 static void nbd_refresh_filename(BlockDriverState *bs) 1986 { 1987 BDRVNBDState *s = bs->opaque; 1988 const char *host = NULL, *port = NULL, *path = NULL; 1989 1990 if (s->saddr->type == SOCKET_ADDRESS_TYPE_INET) { 1991 const InetSocketAddress *inet = &s->saddr->u.inet; 1992 if (!inet->has_ipv4 && !inet->has_ipv6 && !inet->has_to) { 1993 host = inet->host; 1994 port = inet->port; 1995 } 1996 } else if (s->saddr->type == SOCKET_ADDRESS_TYPE_UNIX) { 1997 path = s->saddr->u.q_unix.path; 1998 } /* else can't represent as pseudo-filename */ 1999 2000 if (path && s->export) { 2001 snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2002 "nbd+unix:///%s?socket=%s", s->export, path); 2003 } else if (path && !s->export) { 2004 snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2005 "nbd+unix://?socket=%s", path); 2006 } else if (host && s->export) { 2007 snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2008 "nbd://%s:%s/%s", host, port, s->export); 2009 } else if (host && !s->export) { 2010 snprintf(bs->exact_filename, sizeof(bs->exact_filename), 2011 "nbd://%s:%s", host, port); 2012 } 2013 } 2014 2015 static char *nbd_dirname(BlockDriverState *bs, Error **errp) 2016 { 2017 /* The generic bdrv_dirname() implementation is able to work out some 2018 * directory name for NBD nodes, but that would be wrong. So far there is no 2019 * specification for how "export paths" would work, so NBD does not have 2020 * directory names. */ 2021 error_setg(errp, "Cannot generate a base directory for NBD nodes"); 2022 return NULL; 2023 } 2024 2025 static const char *const nbd_strong_runtime_opts[] = { 2026 "path", 2027 "host", 2028 "port", 2029 "export", 2030 "tls-creds", 2031 "server.", 2032 2033 NULL 2034 }; 2035 2036 static BlockDriver bdrv_nbd = { 2037 .format_name = "nbd", 2038 .protocol_name = "nbd", 2039 .instance_size = sizeof(BDRVNBDState), 2040 .bdrv_parse_filename = nbd_parse_filename, 2041 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2042 .create_opts = &bdrv_create_opts_simple, 2043 .bdrv_file_open = nbd_open, 2044 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2045 .bdrv_co_preadv = nbd_client_co_preadv, 2046 .bdrv_co_pwritev = nbd_client_co_pwritev, 2047 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2048 .bdrv_close = nbd_close, 2049 .bdrv_co_flush_to_os = nbd_co_flush, 2050 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2051 .bdrv_refresh_limits = nbd_refresh_limits, 2052 .bdrv_getlength = nbd_getlength, 2053 .bdrv_detach_aio_context = nbd_client_detach_aio_context, 2054 .bdrv_attach_aio_context = nbd_client_attach_aio_context, 2055 .bdrv_co_drain_begin = nbd_client_co_drain_begin, 2056 .bdrv_co_drain_end = nbd_client_co_drain_end, 2057 .bdrv_refresh_filename = nbd_refresh_filename, 2058 .bdrv_co_block_status = nbd_client_co_block_status, 2059 .bdrv_dirname = nbd_dirname, 2060 .strong_runtime_opts = nbd_strong_runtime_opts, 2061 }; 2062 2063 static BlockDriver bdrv_nbd_tcp = { 2064 .format_name = "nbd", 2065 .protocol_name = "nbd+tcp", 2066 .instance_size = sizeof(BDRVNBDState), 2067 .bdrv_parse_filename = nbd_parse_filename, 2068 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2069 .create_opts = &bdrv_create_opts_simple, 2070 .bdrv_file_open = nbd_open, 2071 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2072 .bdrv_co_preadv = nbd_client_co_preadv, 2073 .bdrv_co_pwritev = nbd_client_co_pwritev, 2074 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2075 .bdrv_close = nbd_close, 2076 .bdrv_co_flush_to_os = nbd_co_flush, 2077 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2078 .bdrv_refresh_limits = nbd_refresh_limits, 2079 .bdrv_getlength = nbd_getlength, 2080 .bdrv_detach_aio_context = nbd_client_detach_aio_context, 2081 .bdrv_attach_aio_context = nbd_client_attach_aio_context, 2082 .bdrv_co_drain_begin = nbd_client_co_drain_begin, 2083 .bdrv_co_drain_end = nbd_client_co_drain_end, 2084 .bdrv_refresh_filename = nbd_refresh_filename, 2085 .bdrv_co_block_status = nbd_client_co_block_status, 2086 .bdrv_dirname = nbd_dirname, 2087 .strong_runtime_opts = nbd_strong_runtime_opts, 2088 }; 2089 2090 static BlockDriver bdrv_nbd_unix = { 2091 .format_name = "nbd", 2092 .protocol_name = "nbd+unix", 2093 .instance_size = sizeof(BDRVNBDState), 2094 .bdrv_parse_filename = nbd_parse_filename, 2095 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 2096 .create_opts = &bdrv_create_opts_simple, 2097 .bdrv_file_open = nbd_open, 2098 .bdrv_reopen_prepare = nbd_client_reopen_prepare, 2099 .bdrv_co_preadv = nbd_client_co_preadv, 2100 .bdrv_co_pwritev = nbd_client_co_pwritev, 2101 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes, 2102 .bdrv_close = nbd_close, 2103 .bdrv_co_flush_to_os = nbd_co_flush, 2104 .bdrv_co_pdiscard = nbd_client_co_pdiscard, 2105 .bdrv_refresh_limits = nbd_refresh_limits, 2106 .bdrv_getlength = nbd_getlength, 2107 .bdrv_detach_aio_context = nbd_client_detach_aio_context, 2108 .bdrv_attach_aio_context = nbd_client_attach_aio_context, 2109 .bdrv_co_drain_begin = nbd_client_co_drain_begin, 2110 .bdrv_co_drain_end = nbd_client_co_drain_end, 2111 .bdrv_refresh_filename = nbd_refresh_filename, 2112 .bdrv_co_block_status = nbd_client_co_block_status, 2113 .bdrv_dirname = nbd_dirname, 2114 .strong_runtime_opts = nbd_strong_runtime_opts, 2115 }; 2116 2117 static void bdrv_nbd_init(void) 2118 { 2119 bdrv_register(&bdrv_nbd); 2120 bdrv_register(&bdrv_nbd_tcp); 2121 bdrv_register(&bdrv_nbd_unix); 2122 } 2123 2124 block_init(bdrv_nbd_init); 2125