1 /* 2 * Replication Block filter 3 * 4 * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. 5 * Copyright (c) 2016 Intel Corporation 6 * Copyright (c) 2016 FUJITSU LIMITED 7 * 8 * Author: 9 * Wen Congyang <wency@cn.fujitsu.com> 10 * 11 * This work is licensed under the terms of the GNU GPL, version 2 or later. 12 * See the COPYING file in the top-level directory. 13 */ 14 15 #include "qemu/osdep.h" 16 #include "qemu/module.h" 17 #include "qemu/option.h" 18 #include "block/nbd.h" 19 #include "block/blockjob.h" 20 #include "block/block_int.h" 21 #include "block/block_backup.h" 22 #include "sysemu/block-backend.h" 23 #include "qapi/error.h" 24 #include "qapi/qmp/qdict.h" 25 #include "block/replication.h" 26 27 typedef enum { 28 BLOCK_REPLICATION_NONE, /* block replication is not started */ 29 BLOCK_REPLICATION_RUNNING, /* block replication is running */ 30 BLOCK_REPLICATION_FAILOVER, /* failover is running in background */ 31 BLOCK_REPLICATION_FAILOVER_FAILED, /* failover failed */ 32 BLOCK_REPLICATION_DONE, /* block replication is done */ 33 } ReplicationStage; 34 35 typedef struct BDRVReplicationState { 36 ReplicationMode mode; 37 ReplicationStage stage; 38 BlockJob *commit_job; 39 BdrvChild *hidden_disk; 40 BdrvChild *secondary_disk; 41 BlockJob *backup_job; 42 char *top_id; 43 ReplicationState *rs; 44 Error *blocker; 45 bool orig_hidden_read_only; 46 bool orig_secondary_read_only; 47 int error; 48 } BDRVReplicationState; 49 50 static void replication_start(ReplicationState *rs, ReplicationMode mode, 51 Error **errp); 52 static void replication_do_checkpoint(ReplicationState *rs, Error **errp); 53 static void replication_get_error(ReplicationState *rs, Error **errp); 54 static void replication_stop(ReplicationState *rs, bool failover, 55 Error **errp); 56 57 #define REPLICATION_MODE "mode" 58 #define REPLICATION_TOP_ID "top-id" 59 static QemuOptsList replication_runtime_opts = { 60 .name = "replication", 61 .head = QTAILQ_HEAD_INITIALIZER(replication_runtime_opts.head), 62 .desc = { 63 { 64 .name = REPLICATION_MODE, 65 .type = QEMU_OPT_STRING, 66 }, 67 { 68 .name = REPLICATION_TOP_ID, 69 .type = QEMU_OPT_STRING, 70 }, 71 { /* end of list */ } 72 }, 73 }; 74 75 static ReplicationOps replication_ops = { 76 .start = replication_start, 77 .checkpoint = replication_do_checkpoint, 78 .get_error = replication_get_error, 79 .stop = replication_stop, 80 }; 81 82 static int replication_open(BlockDriverState *bs, QDict *options, 83 int flags, Error **errp) 84 { 85 int ret; 86 BDRVReplicationState *s = bs->opaque; 87 QemuOpts *opts = NULL; 88 const char *mode; 89 const char *top_id; 90 91 bs->file = bdrv_open_child(NULL, options, "file", bs, &child_of_bds, 92 BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, 93 false, errp); 94 if (!bs->file) { 95 return -EINVAL; 96 } 97 98 ret = -EINVAL; 99 opts = qemu_opts_create(&replication_runtime_opts, NULL, 0, &error_abort); 100 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 101 goto fail; 102 } 103 104 mode = qemu_opt_get(opts, REPLICATION_MODE); 105 if (!mode) { 106 error_setg(errp, "Missing the option mode"); 107 goto fail; 108 } 109 110 if (!strcmp(mode, "primary")) { 111 s->mode = REPLICATION_MODE_PRIMARY; 112 top_id = qemu_opt_get(opts, REPLICATION_TOP_ID); 113 if (top_id) { 114 error_setg(errp, 115 "The primary side does not support option top-id"); 116 goto fail; 117 } 118 } else if (!strcmp(mode, "secondary")) { 119 s->mode = REPLICATION_MODE_SECONDARY; 120 top_id = qemu_opt_get(opts, REPLICATION_TOP_ID); 121 s->top_id = g_strdup(top_id); 122 if (!s->top_id) { 123 error_setg(errp, "Missing the option top-id"); 124 goto fail; 125 } 126 } else { 127 error_setg(errp, 128 "The option mode's value should be primary or secondary"); 129 goto fail; 130 } 131 132 s->rs = replication_new(bs, &replication_ops); 133 134 ret = 0; 135 136 fail: 137 qemu_opts_del(opts); 138 return ret; 139 } 140 141 static void replication_close(BlockDriverState *bs) 142 { 143 BDRVReplicationState *s = bs->opaque; 144 Job *commit_job; 145 GLOBAL_STATE_CODE(); 146 147 if (s->stage == BLOCK_REPLICATION_RUNNING) { 148 replication_stop(s->rs, false, NULL); 149 } 150 if (s->stage == BLOCK_REPLICATION_FAILOVER) { 151 commit_job = &s->commit_job->job; 152 assert(commit_job->aio_context == qemu_get_current_aio_context()); 153 job_cancel_sync(commit_job, false); 154 } 155 156 if (s->mode == REPLICATION_MODE_SECONDARY) { 157 g_free(s->top_id); 158 } 159 160 replication_remove(s->rs); 161 } 162 163 static void replication_child_perm(BlockDriverState *bs, BdrvChild *c, 164 BdrvChildRole role, 165 BlockReopenQueue *reopen_queue, 166 uint64_t perm, uint64_t shared, 167 uint64_t *nperm, uint64_t *nshared) 168 { 169 if (role & BDRV_CHILD_PRIMARY) { 170 *nperm = BLK_PERM_CONSISTENT_READ; 171 } else { 172 *nperm = 0; 173 } 174 175 if ((bs->open_flags & (BDRV_O_INACTIVE | BDRV_O_RDWR)) == BDRV_O_RDWR) { 176 *nperm |= BLK_PERM_WRITE; 177 } 178 *nshared = BLK_PERM_CONSISTENT_READ 179 | BLK_PERM_WRITE 180 | BLK_PERM_WRITE_UNCHANGED; 181 return; 182 } 183 184 static int64_t replication_getlength(BlockDriverState *bs) 185 { 186 return bdrv_getlength(bs->file->bs); 187 } 188 189 static int replication_get_io_status(BDRVReplicationState *s) 190 { 191 switch (s->stage) { 192 case BLOCK_REPLICATION_NONE: 193 return -EIO; 194 case BLOCK_REPLICATION_RUNNING: 195 return 0; 196 case BLOCK_REPLICATION_FAILOVER: 197 return s->mode == REPLICATION_MODE_PRIMARY ? -EIO : 0; 198 case BLOCK_REPLICATION_FAILOVER_FAILED: 199 return s->mode == REPLICATION_MODE_PRIMARY ? -EIO : 1; 200 case BLOCK_REPLICATION_DONE: 201 /* 202 * active commit job completes, and active disk and secondary_disk 203 * is swapped, so we can operate bs->file directly 204 */ 205 return s->mode == REPLICATION_MODE_PRIMARY ? -EIO : 0; 206 default: 207 abort(); 208 } 209 } 210 211 static int replication_return_value(BDRVReplicationState *s, int ret) 212 { 213 if (s->mode == REPLICATION_MODE_SECONDARY) { 214 return ret; 215 } 216 217 if (ret < 0) { 218 s->error = ret; 219 ret = 0; 220 } 221 222 return ret; 223 } 224 225 static coroutine_fn int replication_co_readv(BlockDriverState *bs, 226 int64_t sector_num, 227 int remaining_sectors, 228 QEMUIOVector *qiov) 229 { 230 BDRVReplicationState *s = bs->opaque; 231 int ret; 232 233 if (s->mode == REPLICATION_MODE_PRIMARY) { 234 /* We only use it to forward primary write requests */ 235 return -EIO; 236 } 237 238 ret = replication_get_io_status(s); 239 if (ret < 0) { 240 return ret; 241 } 242 243 ret = bdrv_co_preadv(bs->file, sector_num * BDRV_SECTOR_SIZE, 244 remaining_sectors * BDRV_SECTOR_SIZE, qiov, 0); 245 246 return replication_return_value(s, ret); 247 } 248 249 static coroutine_fn int replication_co_writev(BlockDriverState *bs, 250 int64_t sector_num, 251 int remaining_sectors, 252 QEMUIOVector *qiov, 253 int flags) 254 { 255 BDRVReplicationState *s = bs->opaque; 256 QEMUIOVector hd_qiov; 257 uint64_t bytes_done = 0; 258 BdrvChild *top = bs->file; 259 BdrvChild *base = s->secondary_disk; 260 BdrvChild *target; 261 int ret; 262 int64_t n; 263 264 assert(!flags); 265 ret = replication_get_io_status(s); 266 if (ret < 0) { 267 goto out; 268 } 269 270 if (ret == 0) { 271 ret = bdrv_co_pwritev(top, sector_num * BDRV_SECTOR_SIZE, 272 remaining_sectors * BDRV_SECTOR_SIZE, qiov, 0); 273 return replication_return_value(s, ret); 274 } 275 276 /* 277 * Failover failed, only write to active disk if the sectors 278 * have already been allocated in active disk/hidden disk. 279 */ 280 qemu_iovec_init(&hd_qiov, qiov->niov); 281 while (remaining_sectors > 0) { 282 int64_t count; 283 284 ret = bdrv_is_allocated_above(top->bs, base->bs, false, 285 sector_num * BDRV_SECTOR_SIZE, 286 remaining_sectors * BDRV_SECTOR_SIZE, 287 &count); 288 if (ret < 0) { 289 goto out1; 290 } 291 292 assert(QEMU_IS_ALIGNED(count, BDRV_SECTOR_SIZE)); 293 n = count >> BDRV_SECTOR_BITS; 294 qemu_iovec_reset(&hd_qiov); 295 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, count); 296 297 target = ret ? top : base; 298 ret = bdrv_co_pwritev(target, sector_num * BDRV_SECTOR_SIZE, 299 n * BDRV_SECTOR_SIZE, &hd_qiov, 0); 300 if (ret < 0) { 301 goto out1; 302 } 303 304 remaining_sectors -= n; 305 sector_num += n; 306 bytes_done += count; 307 } 308 309 out1: 310 qemu_iovec_destroy(&hd_qiov); 311 out: 312 return ret; 313 } 314 315 static void secondary_do_checkpoint(BlockDriverState *bs, Error **errp) 316 { 317 BDRVReplicationState *s = bs->opaque; 318 BdrvChild *active_disk = bs->file; 319 Error *local_err = NULL; 320 int ret; 321 322 if (!s->backup_job) { 323 error_setg(errp, "Backup job was cancelled unexpectedly"); 324 return; 325 } 326 327 backup_do_checkpoint(s->backup_job, &local_err); 328 if (local_err) { 329 error_propagate(errp, local_err); 330 return; 331 } 332 333 if (!active_disk->bs->drv) { 334 error_setg(errp, "Active disk %s is ejected", 335 active_disk->bs->node_name); 336 return; 337 } 338 339 ret = bdrv_make_empty(active_disk, errp); 340 if (ret < 0) { 341 return; 342 } 343 344 if (!s->hidden_disk->bs->drv) { 345 error_setg(errp, "Hidden disk %s is ejected", 346 s->hidden_disk->bs->node_name); 347 return; 348 } 349 350 ret = bdrv_make_empty(s->hidden_disk, errp); 351 if (ret < 0) { 352 return; 353 } 354 } 355 356 /* This function is supposed to be called twice: 357 * first with writable = true, then with writable = false. 358 * The first call puts s->hidden_disk and s->secondary_disk in 359 * r/w mode, and the second puts them back in their original state. 360 */ 361 static void reopen_backing_file(BlockDriverState *bs, bool writable, 362 Error **errp) 363 { 364 BDRVReplicationState *s = bs->opaque; 365 BdrvChild *hidden_disk, *secondary_disk; 366 BlockReopenQueue *reopen_queue = NULL; 367 368 /* 369 * s->hidden_disk and s->secondary_disk may not be set yet, as they will 370 * only be set after the children are writable. 371 */ 372 hidden_disk = bs->file->bs->backing; 373 secondary_disk = hidden_disk->bs->backing; 374 375 if (writable) { 376 s->orig_hidden_read_only = bdrv_is_read_only(hidden_disk->bs); 377 s->orig_secondary_read_only = bdrv_is_read_only(secondary_disk->bs); 378 } 379 380 bdrv_subtree_drained_begin(hidden_disk->bs); 381 bdrv_subtree_drained_begin(secondary_disk->bs); 382 383 if (s->orig_hidden_read_only) { 384 QDict *opts = qdict_new(); 385 qdict_put_bool(opts, BDRV_OPT_READ_ONLY, !writable); 386 reopen_queue = bdrv_reopen_queue(reopen_queue, hidden_disk->bs, 387 opts, true); 388 } 389 390 if (s->orig_secondary_read_only) { 391 QDict *opts = qdict_new(); 392 qdict_put_bool(opts, BDRV_OPT_READ_ONLY, !writable); 393 reopen_queue = bdrv_reopen_queue(reopen_queue, secondary_disk->bs, 394 opts, true); 395 } 396 397 if (reopen_queue) { 398 AioContext *ctx = bdrv_get_aio_context(bs); 399 if (ctx != qemu_get_aio_context()) { 400 aio_context_release(ctx); 401 } 402 bdrv_reopen_multiple(reopen_queue, errp); 403 if (ctx != qemu_get_aio_context()) { 404 aio_context_acquire(ctx); 405 } 406 } 407 408 bdrv_subtree_drained_end(hidden_disk->bs); 409 bdrv_subtree_drained_end(secondary_disk->bs); 410 } 411 412 static void backup_job_cleanup(BlockDriverState *bs) 413 { 414 BDRVReplicationState *s = bs->opaque; 415 BlockDriverState *top_bs; 416 417 s->backup_job = NULL; 418 419 top_bs = bdrv_lookup_bs(s->top_id, s->top_id, NULL); 420 if (!top_bs) { 421 return; 422 } 423 bdrv_op_unblock_all(top_bs, s->blocker); 424 error_free(s->blocker); 425 reopen_backing_file(bs, false, NULL); 426 } 427 428 static void backup_job_completed(void *opaque, int ret) 429 { 430 BlockDriverState *bs = opaque; 431 BDRVReplicationState *s = bs->opaque; 432 433 if (s->stage != BLOCK_REPLICATION_FAILOVER) { 434 /* The backup job is cancelled unexpectedly */ 435 s->error = -EIO; 436 } 437 438 backup_job_cleanup(bs); 439 } 440 441 static bool check_top_bs(BlockDriverState *top_bs, BlockDriverState *bs) 442 { 443 BdrvChild *child; 444 445 /* The bs itself is the top_bs */ 446 if (top_bs == bs) { 447 return true; 448 } 449 450 /* Iterate over top_bs's children */ 451 QLIST_FOREACH(child, &top_bs->children, next) { 452 if (child->bs == bs || check_top_bs(child->bs, bs)) { 453 return true; 454 } 455 } 456 457 return false; 458 } 459 460 static void replication_start(ReplicationState *rs, ReplicationMode mode, 461 Error **errp) 462 { 463 BlockDriverState *bs = rs->opaque; 464 BDRVReplicationState *s; 465 BlockDriverState *top_bs; 466 BdrvChild *active_disk, *hidden_disk, *secondary_disk; 467 int64_t active_length, hidden_length, disk_length; 468 AioContext *aio_context; 469 Error *local_err = NULL; 470 BackupPerf perf = { .use_copy_range = true, .max_workers = 1 }; 471 472 aio_context = bdrv_get_aio_context(bs); 473 aio_context_acquire(aio_context); 474 s = bs->opaque; 475 476 if (s->stage == BLOCK_REPLICATION_DONE || 477 s->stage == BLOCK_REPLICATION_FAILOVER) { 478 /* 479 * This case happens when a secondary is promoted to primary. 480 * Ignore the request because the secondary side of replication 481 * doesn't have to do anything anymore. 482 */ 483 aio_context_release(aio_context); 484 return; 485 } 486 487 if (s->stage != BLOCK_REPLICATION_NONE) { 488 error_setg(errp, "Block replication is running or done"); 489 aio_context_release(aio_context); 490 return; 491 } 492 493 if (s->mode != mode) { 494 error_setg(errp, "The parameter mode's value is invalid, needs %d," 495 " but got %d", s->mode, mode); 496 aio_context_release(aio_context); 497 return; 498 } 499 500 switch (s->mode) { 501 case REPLICATION_MODE_PRIMARY: 502 break; 503 case REPLICATION_MODE_SECONDARY: 504 active_disk = bs->file; 505 if (!active_disk || !active_disk->bs || !active_disk->bs->backing) { 506 error_setg(errp, "Active disk doesn't have backing file"); 507 aio_context_release(aio_context); 508 return; 509 } 510 511 hidden_disk = active_disk->bs->backing; 512 if (!hidden_disk->bs || !hidden_disk->bs->backing) { 513 error_setg(errp, "Hidden disk doesn't have backing file"); 514 aio_context_release(aio_context); 515 return; 516 } 517 518 secondary_disk = hidden_disk->bs->backing; 519 if (!secondary_disk->bs || !bdrv_has_blk(secondary_disk->bs)) { 520 error_setg(errp, "The secondary disk doesn't have block backend"); 521 aio_context_release(aio_context); 522 return; 523 } 524 525 /* verify the length */ 526 active_length = bdrv_getlength(active_disk->bs); 527 hidden_length = bdrv_getlength(hidden_disk->bs); 528 disk_length = bdrv_getlength(secondary_disk->bs); 529 if (active_length < 0 || hidden_length < 0 || disk_length < 0 || 530 active_length != hidden_length || hidden_length != disk_length) { 531 error_setg(errp, "Active disk, hidden disk, secondary disk's length" 532 " are not the same"); 533 aio_context_release(aio_context); 534 return; 535 } 536 537 /* Must be true, or the bdrv_getlength() calls would have failed */ 538 assert(active_disk->bs->drv && hidden_disk->bs->drv); 539 540 if (!active_disk->bs->drv->bdrv_make_empty || 541 !hidden_disk->bs->drv->bdrv_make_empty) { 542 error_setg(errp, 543 "Active disk or hidden disk doesn't support make_empty"); 544 aio_context_release(aio_context); 545 return; 546 } 547 548 /* reopen the backing file in r/w mode */ 549 reopen_backing_file(bs, true, &local_err); 550 if (local_err) { 551 error_propagate(errp, local_err); 552 aio_context_release(aio_context); 553 return; 554 } 555 556 bdrv_ref(hidden_disk->bs); 557 s->hidden_disk = bdrv_attach_child(bs, hidden_disk->bs, "hidden disk", 558 &child_of_bds, BDRV_CHILD_DATA, 559 &local_err); 560 if (local_err) { 561 error_propagate(errp, local_err); 562 aio_context_release(aio_context); 563 return; 564 } 565 566 bdrv_ref(secondary_disk->bs); 567 s->secondary_disk = bdrv_attach_child(bs, secondary_disk->bs, 568 "secondary disk", &child_of_bds, 569 BDRV_CHILD_DATA, &local_err); 570 if (local_err) { 571 error_propagate(errp, local_err); 572 aio_context_release(aio_context); 573 return; 574 } 575 576 /* start backup job now */ 577 error_setg(&s->blocker, 578 "Block device is in use by internal backup job"); 579 580 top_bs = bdrv_lookup_bs(s->top_id, s->top_id, NULL); 581 if (!top_bs || !bdrv_is_root_node(top_bs) || 582 !check_top_bs(top_bs, bs)) { 583 error_setg(errp, "No top_bs or it is invalid"); 584 reopen_backing_file(bs, false, NULL); 585 aio_context_release(aio_context); 586 return; 587 } 588 bdrv_op_block_all(top_bs, s->blocker); 589 bdrv_op_unblock(top_bs, BLOCK_OP_TYPE_DATAPLANE, s->blocker); 590 591 s->backup_job = backup_job_create( 592 NULL, s->secondary_disk->bs, s->hidden_disk->bs, 593 0, MIRROR_SYNC_MODE_NONE, NULL, 0, false, NULL, 594 &perf, 595 BLOCKDEV_ON_ERROR_REPORT, 596 BLOCKDEV_ON_ERROR_REPORT, JOB_INTERNAL, 597 backup_job_completed, bs, NULL, &local_err); 598 if (local_err) { 599 error_propagate(errp, local_err); 600 backup_job_cleanup(bs); 601 aio_context_release(aio_context); 602 return; 603 } 604 job_start(&s->backup_job->job); 605 break; 606 default: 607 aio_context_release(aio_context); 608 abort(); 609 } 610 611 s->stage = BLOCK_REPLICATION_RUNNING; 612 613 if (s->mode == REPLICATION_MODE_SECONDARY) { 614 secondary_do_checkpoint(bs, errp); 615 } 616 617 s->error = 0; 618 aio_context_release(aio_context); 619 } 620 621 static void replication_do_checkpoint(ReplicationState *rs, Error **errp) 622 { 623 BlockDriverState *bs = rs->opaque; 624 BDRVReplicationState *s; 625 AioContext *aio_context; 626 627 aio_context = bdrv_get_aio_context(bs); 628 aio_context_acquire(aio_context); 629 s = bs->opaque; 630 631 if (s->stage == BLOCK_REPLICATION_DONE || 632 s->stage == BLOCK_REPLICATION_FAILOVER) { 633 /* 634 * This case happens when a secondary was promoted to primary. 635 * Ignore the request because the secondary side of replication 636 * doesn't have to do anything anymore. 637 */ 638 aio_context_release(aio_context); 639 return; 640 } 641 642 if (s->mode == REPLICATION_MODE_SECONDARY) { 643 secondary_do_checkpoint(bs, errp); 644 } 645 aio_context_release(aio_context); 646 } 647 648 static void replication_get_error(ReplicationState *rs, Error **errp) 649 { 650 BlockDriverState *bs = rs->opaque; 651 BDRVReplicationState *s; 652 AioContext *aio_context; 653 654 aio_context = bdrv_get_aio_context(bs); 655 aio_context_acquire(aio_context); 656 s = bs->opaque; 657 658 if (s->stage == BLOCK_REPLICATION_NONE) { 659 error_setg(errp, "Block replication is not running"); 660 aio_context_release(aio_context); 661 return; 662 } 663 664 if (s->error) { 665 error_setg(errp, "I/O error occurred"); 666 aio_context_release(aio_context); 667 return; 668 } 669 aio_context_release(aio_context); 670 } 671 672 static void replication_done(void *opaque, int ret) 673 { 674 BlockDriverState *bs = opaque; 675 BDRVReplicationState *s = bs->opaque; 676 677 if (ret == 0) { 678 s->stage = BLOCK_REPLICATION_DONE; 679 680 bdrv_unref_child(bs, s->secondary_disk); 681 s->secondary_disk = NULL; 682 bdrv_unref_child(bs, s->hidden_disk); 683 s->hidden_disk = NULL; 684 s->error = 0; 685 } else { 686 s->stage = BLOCK_REPLICATION_FAILOVER_FAILED; 687 s->error = -EIO; 688 } 689 } 690 691 static void replication_stop(ReplicationState *rs, bool failover, Error **errp) 692 { 693 BlockDriverState *bs = rs->opaque; 694 BDRVReplicationState *s; 695 AioContext *aio_context; 696 697 aio_context = bdrv_get_aio_context(bs); 698 aio_context_acquire(aio_context); 699 s = bs->opaque; 700 701 if (s->stage == BLOCK_REPLICATION_DONE || 702 s->stage == BLOCK_REPLICATION_FAILOVER) { 703 /* 704 * This case happens when a secondary was promoted to primary. 705 * Ignore the request because the secondary side of replication 706 * doesn't have to do anything anymore. 707 */ 708 aio_context_release(aio_context); 709 return; 710 } 711 712 if (s->stage != BLOCK_REPLICATION_RUNNING) { 713 error_setg(errp, "Block replication is not running"); 714 aio_context_release(aio_context); 715 return; 716 } 717 718 switch (s->mode) { 719 case REPLICATION_MODE_PRIMARY: 720 s->stage = BLOCK_REPLICATION_DONE; 721 s->error = 0; 722 break; 723 case REPLICATION_MODE_SECONDARY: 724 /* 725 * This BDS will be closed, and the job should be completed 726 * before the BDS is closed, because we will access hidden 727 * disk, secondary disk in backup_job_completed(). 728 */ 729 if (s->backup_job) { 730 aio_context_release(aio_context); 731 job_cancel_sync(&s->backup_job->job, true); 732 aio_context_acquire(aio_context); 733 } 734 735 if (!failover) { 736 secondary_do_checkpoint(bs, errp); 737 s->stage = BLOCK_REPLICATION_DONE; 738 aio_context_release(aio_context); 739 return; 740 } 741 742 s->stage = BLOCK_REPLICATION_FAILOVER; 743 s->commit_job = commit_active_start( 744 NULL, bs->file->bs, s->secondary_disk->bs, 745 JOB_INTERNAL, 0, BLOCKDEV_ON_ERROR_REPORT, 746 NULL, replication_done, bs, true, errp); 747 break; 748 default: 749 aio_context_release(aio_context); 750 abort(); 751 } 752 aio_context_release(aio_context); 753 } 754 755 static const char *const replication_strong_runtime_opts[] = { 756 REPLICATION_MODE, 757 REPLICATION_TOP_ID, 758 759 NULL 760 }; 761 762 static BlockDriver bdrv_replication = { 763 .format_name = "replication", 764 .instance_size = sizeof(BDRVReplicationState), 765 766 .bdrv_open = replication_open, 767 .bdrv_close = replication_close, 768 .bdrv_child_perm = replication_child_perm, 769 770 .bdrv_getlength = replication_getlength, 771 .bdrv_co_readv = replication_co_readv, 772 .bdrv_co_writev = replication_co_writev, 773 774 .is_filter = true, 775 776 .has_variable_length = true, 777 .strong_runtime_opts = replication_strong_runtime_opts, 778 }; 779 780 static void bdrv_replication_init(void) 781 { 782 bdrv_register(&bdrv_replication); 783 } 784 785 block_init(bdrv_replication_init); 786