1 /* 2 * Block protocol for I/O error injection 3 * 4 * Copyright (C) 2016-2017 Red Hat, Inc. 5 * Copyright (c) 2010 Kevin Wolf <kwolf@redhat.com> 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 * THE SOFTWARE. 24 */ 25 26 #include "qemu/osdep.h" 27 #include "qapi/error.h" 28 #include "qemu/cutils.h" 29 #include "qemu/config-file.h" 30 #include "block/block-io.h" 31 #include "block/block_int.h" 32 #include "block/qdict.h" 33 #include "qemu/module.h" 34 #include "qemu/option.h" 35 #include "qapi/qapi-visit-block-core.h" 36 #include "qapi/qmp/qdict.h" 37 #include "qapi/qmp/qlist.h" 38 #include "qapi/qmp/qstring.h" 39 #include "qapi/qobject-input-visitor.h" 40 #include "sysemu/qtest.h" 41 42 /* All APIs are thread-safe */ 43 44 typedef struct BDRVBlkdebugState { 45 /* IN: initialized in blkdebug_open() and never changed */ 46 uint64_t align; 47 uint64_t max_transfer; 48 uint64_t opt_write_zero; 49 uint64_t max_write_zero; 50 uint64_t opt_discard; 51 uint64_t max_discard; 52 char *config_file; /* For blkdebug_refresh_filename() */ 53 /* initialized in blkdebug_parse_perms() */ 54 uint64_t take_child_perms; 55 uint64_t unshare_child_perms; 56 57 /* State. Protected by lock */ 58 int state; 59 QLIST_HEAD(, BlkdebugRule) rules[BLKDBG__MAX]; 60 QSIMPLEQ_HEAD(, BlkdebugRule) active_rules; 61 QLIST_HEAD(, BlkdebugSuspendedReq) suspended_reqs; 62 QemuMutex lock; 63 } BDRVBlkdebugState; 64 65 typedef struct BlkdebugAIOCB { 66 BlockAIOCB common; 67 int ret; 68 } BlkdebugAIOCB; 69 70 typedef struct BlkdebugSuspendedReq { 71 /* IN: initialized in suspend_request() */ 72 Coroutine *co; 73 char *tag; 74 75 /* List entry protected BDRVBlkdebugState's lock */ 76 QLIST_ENTRY(BlkdebugSuspendedReq) next; 77 } BlkdebugSuspendedReq; 78 79 enum { 80 ACTION_INJECT_ERROR, 81 ACTION_SET_STATE, 82 ACTION_SUSPEND, 83 ACTION__MAX, 84 }; 85 86 typedef struct BlkdebugRule { 87 /* IN: initialized in add_rule() or blkdebug_debug_breakpoint() */ 88 BlkdebugEvent event; 89 int action; 90 int state; 91 union { 92 struct { 93 uint64_t iotype_mask; 94 int error; 95 int immediately; 96 int once; 97 int64_t offset; 98 } inject; 99 struct { 100 int new_state; 101 } set_state; 102 struct { 103 char *tag; 104 } suspend; 105 } options; 106 107 /* List entries protected BDRVBlkdebugState's lock */ 108 QLIST_ENTRY(BlkdebugRule) next; 109 QSIMPLEQ_ENTRY(BlkdebugRule) active_next; 110 } BlkdebugRule; 111 112 QEMU_BUILD_BUG_MSG(BLKDEBUG_IO_TYPE__MAX > 64, 113 "BlkdebugIOType mask does not fit into an uint64_t"); 114 115 static QemuOptsList inject_error_opts = { 116 .name = "inject-error", 117 .head = QTAILQ_HEAD_INITIALIZER(inject_error_opts.head), 118 .desc = { 119 { 120 .name = "event", 121 .type = QEMU_OPT_STRING, 122 }, 123 { 124 .name = "state", 125 .type = QEMU_OPT_NUMBER, 126 }, 127 { 128 .name = "iotype", 129 .type = QEMU_OPT_STRING, 130 }, 131 { 132 .name = "errno", 133 .type = QEMU_OPT_NUMBER, 134 }, 135 { 136 .name = "sector", 137 .type = QEMU_OPT_NUMBER, 138 }, 139 { 140 .name = "once", 141 .type = QEMU_OPT_BOOL, 142 }, 143 { 144 .name = "immediately", 145 .type = QEMU_OPT_BOOL, 146 }, 147 { /* end of list */ } 148 }, 149 }; 150 151 static QemuOptsList set_state_opts = { 152 .name = "set-state", 153 .head = QTAILQ_HEAD_INITIALIZER(set_state_opts.head), 154 .desc = { 155 { 156 .name = "event", 157 .type = QEMU_OPT_STRING, 158 }, 159 { 160 .name = "state", 161 .type = QEMU_OPT_NUMBER, 162 }, 163 { 164 .name = "new_state", 165 .type = QEMU_OPT_NUMBER, 166 }, 167 { /* end of list */ } 168 }, 169 }; 170 171 static QemuOptsList *config_groups[] = { 172 &inject_error_opts, 173 &set_state_opts, 174 NULL 175 }; 176 177 struct add_rule_data { 178 BDRVBlkdebugState *s; 179 int action; 180 }; 181 182 static int add_rule(void *opaque, QemuOpts *opts, Error **errp) 183 { 184 struct add_rule_data *d = opaque; 185 BDRVBlkdebugState *s = d->s; 186 const char *event_name; 187 int event; 188 struct BlkdebugRule *rule; 189 int64_t sector; 190 BlkdebugIOType iotype; 191 Error *local_error = NULL; 192 193 /* Find the right event for the rule */ 194 event_name = qemu_opt_get(opts, "event"); 195 if (!event_name) { 196 error_setg(errp, "Missing event name for rule"); 197 return -1; 198 } 199 event = qapi_enum_parse(&BlkdebugEvent_lookup, event_name, -1, errp); 200 if (event < 0) { 201 return -1; 202 } 203 204 /* Set attributes common for all actions */ 205 rule = g_malloc0(sizeof(*rule)); 206 *rule = (struct BlkdebugRule) { 207 .event = event, 208 .action = d->action, 209 .state = qemu_opt_get_number(opts, "state", 0), 210 }; 211 212 /* Parse action-specific options */ 213 switch (d->action) { 214 case ACTION_INJECT_ERROR: 215 rule->options.inject.error = qemu_opt_get_number(opts, "errno", EIO); 216 rule->options.inject.once = qemu_opt_get_bool(opts, "once", 0); 217 rule->options.inject.immediately = 218 qemu_opt_get_bool(opts, "immediately", 0); 219 sector = qemu_opt_get_number(opts, "sector", -1); 220 rule->options.inject.offset = 221 sector == -1 ? -1 : sector * BDRV_SECTOR_SIZE; 222 223 iotype = qapi_enum_parse(&BlkdebugIOType_lookup, 224 qemu_opt_get(opts, "iotype"), 225 BLKDEBUG_IO_TYPE__MAX, &local_error); 226 if (local_error) { 227 error_propagate(errp, local_error); 228 g_free(rule); 229 return -1; 230 } 231 if (iotype != BLKDEBUG_IO_TYPE__MAX) { 232 rule->options.inject.iotype_mask = (1ull << iotype); 233 } else { 234 /* Apply the default */ 235 rule->options.inject.iotype_mask = 236 (1ull << BLKDEBUG_IO_TYPE_READ) 237 | (1ull << BLKDEBUG_IO_TYPE_WRITE) 238 | (1ull << BLKDEBUG_IO_TYPE_WRITE_ZEROES) 239 | (1ull << BLKDEBUG_IO_TYPE_DISCARD) 240 | (1ull << BLKDEBUG_IO_TYPE_FLUSH); 241 } 242 243 break; 244 245 case ACTION_SET_STATE: 246 rule->options.set_state.new_state = 247 qemu_opt_get_number(opts, "new_state", 0); 248 break; 249 250 case ACTION_SUSPEND: 251 rule->options.suspend.tag = 252 g_strdup(qemu_opt_get(opts, "tag")); 253 break; 254 }; 255 256 /* Add the rule */ 257 qemu_mutex_lock(&s->lock); 258 QLIST_INSERT_HEAD(&s->rules[event], rule, next); 259 qemu_mutex_unlock(&s->lock); 260 261 return 0; 262 } 263 264 /* Called with lock held or from .bdrv_close */ 265 static void remove_rule(BlkdebugRule *rule) 266 { 267 switch (rule->action) { 268 case ACTION_INJECT_ERROR: 269 case ACTION_SET_STATE: 270 break; 271 case ACTION_SUSPEND: 272 g_free(rule->options.suspend.tag); 273 break; 274 } 275 276 QLIST_REMOVE(rule, next); 277 g_free(rule); 278 } 279 280 static int read_config(BDRVBlkdebugState *s, const char *filename, 281 QDict *options, Error **errp) 282 { 283 FILE *f = NULL; 284 int ret; 285 struct add_rule_data d; 286 Error *local_err = NULL; 287 288 if (filename) { 289 f = fopen(filename, "r"); 290 if (f == NULL) { 291 error_setg_errno(errp, errno, "Could not read blkdebug config file"); 292 return -errno; 293 } 294 295 ret = qemu_config_parse(f, config_groups, filename, errp); 296 if (ret < 0) { 297 goto fail; 298 } 299 } 300 301 if (!qemu_config_parse_qdict(options, config_groups, errp)) { 302 ret = -EINVAL; 303 goto fail; 304 } 305 306 d.s = s; 307 d.action = ACTION_INJECT_ERROR; 308 qemu_opts_foreach(&inject_error_opts, add_rule, &d, &local_err); 309 if (local_err) { 310 error_propagate(errp, local_err); 311 ret = -EINVAL; 312 goto fail; 313 } 314 315 d.action = ACTION_SET_STATE; 316 qemu_opts_foreach(&set_state_opts, add_rule, &d, &local_err); 317 if (local_err) { 318 error_propagate(errp, local_err); 319 ret = -EINVAL; 320 goto fail; 321 } 322 323 ret = 0; 324 fail: 325 qemu_opts_reset(&inject_error_opts); 326 qemu_opts_reset(&set_state_opts); 327 if (f) { 328 fclose(f); 329 } 330 return ret; 331 } 332 333 /* Valid blkdebug filenames look like blkdebug:path/to/config:path/to/image */ 334 static void blkdebug_parse_filename(const char *filename, QDict *options, 335 Error **errp) 336 { 337 const char *c; 338 339 /* Parse the blkdebug: prefix */ 340 if (!strstart(filename, "blkdebug:", &filename)) { 341 /* There was no prefix; therefore, all options have to be already 342 present in the QDict (except for the filename) */ 343 qdict_put_str(options, "x-image", filename); 344 return; 345 } 346 347 /* Parse config file path */ 348 c = strchr(filename, ':'); 349 if (c == NULL) { 350 error_setg(errp, "blkdebug requires both config file and image path"); 351 return; 352 } 353 354 if (c != filename) { 355 QString *config_path; 356 config_path = qstring_from_substr(filename, 0, c - filename); 357 qdict_put(options, "config", config_path); 358 } 359 360 /* TODO Allow multi-level nesting and set file.filename here */ 361 filename = c + 1; 362 qdict_put_str(options, "x-image", filename); 363 } 364 365 static int blkdebug_parse_perm_list(uint64_t *dest, QDict *options, 366 const char *prefix, Error **errp) 367 { 368 int ret = 0; 369 QDict *subqdict = NULL; 370 QObject *crumpled_subqdict = NULL; 371 Visitor *v = NULL; 372 BlockPermissionList *perm_list = NULL, *element; 373 374 *dest = 0; 375 376 qdict_extract_subqdict(options, &subqdict, prefix); 377 if (!qdict_size(subqdict)) { 378 goto out; 379 } 380 381 crumpled_subqdict = qdict_crumple(subqdict, errp); 382 if (!crumpled_subqdict) { 383 ret = -EINVAL; 384 goto out; 385 } 386 387 v = qobject_input_visitor_new(crumpled_subqdict); 388 if (!visit_type_BlockPermissionList(v, NULL, &perm_list, errp)) { 389 ret = -EINVAL; 390 goto out; 391 } 392 393 for (element = perm_list; element; element = element->next) { 394 *dest |= bdrv_qapi_perm_to_blk_perm(element->value); 395 } 396 397 out: 398 qapi_free_BlockPermissionList(perm_list); 399 visit_free(v); 400 qobject_unref(subqdict); 401 qobject_unref(crumpled_subqdict); 402 return ret; 403 } 404 405 static int blkdebug_parse_perms(BDRVBlkdebugState *s, QDict *options, 406 Error **errp) 407 { 408 int ret; 409 410 ret = blkdebug_parse_perm_list(&s->take_child_perms, options, 411 "take-child-perms.", errp); 412 if (ret < 0) { 413 return ret; 414 } 415 416 ret = blkdebug_parse_perm_list(&s->unshare_child_perms, options, 417 "unshare-child-perms.", errp); 418 if (ret < 0) { 419 return ret; 420 } 421 422 return 0; 423 } 424 425 static QemuOptsList runtime_opts = { 426 .name = "blkdebug", 427 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 428 .desc = { 429 { 430 .name = "config", 431 .type = QEMU_OPT_STRING, 432 .help = "Path to the configuration file", 433 }, 434 { 435 .name = "x-image", 436 .type = QEMU_OPT_STRING, 437 .help = "[internal use only, will be removed]", 438 }, 439 { 440 .name = "align", 441 .type = QEMU_OPT_SIZE, 442 .help = "Required alignment in bytes", 443 }, 444 { 445 .name = "max-transfer", 446 .type = QEMU_OPT_SIZE, 447 .help = "Maximum transfer size in bytes", 448 }, 449 { 450 .name = "opt-write-zero", 451 .type = QEMU_OPT_SIZE, 452 .help = "Optimum write zero alignment in bytes", 453 }, 454 { 455 .name = "max-write-zero", 456 .type = QEMU_OPT_SIZE, 457 .help = "Maximum write zero size in bytes", 458 }, 459 { 460 .name = "opt-discard", 461 .type = QEMU_OPT_SIZE, 462 .help = "Optimum discard alignment in bytes", 463 }, 464 { 465 .name = "max-discard", 466 .type = QEMU_OPT_SIZE, 467 .help = "Maximum discard size in bytes", 468 }, 469 { /* end of list */ } 470 }, 471 }; 472 473 static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags, 474 Error **errp) 475 { 476 BDRVBlkdebugState *s = bs->opaque; 477 QemuOpts *opts; 478 int ret; 479 uint64_t align; 480 481 qemu_mutex_init(&s->lock); 482 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 483 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 484 ret = -EINVAL; 485 goto out; 486 } 487 488 /* Read rules from config file or command line options */ 489 s->config_file = g_strdup(qemu_opt_get(opts, "config")); 490 ret = read_config(s, s->config_file, options, errp); 491 if (ret) { 492 goto out; 493 } 494 495 /* Set initial state */ 496 s->state = 1; 497 498 /* Parse permissions modifiers before opening the image file */ 499 ret = blkdebug_parse_perms(s, options, errp); 500 if (ret < 0) { 501 goto out; 502 } 503 504 /* Open the image file */ 505 ret = bdrv_open_file_child(qemu_opt_get(opts, "x-image"), options, "image", 506 bs, errp); 507 if (ret < 0) { 508 goto out; 509 } 510 511 bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED | 512 (BDRV_REQ_FUA & bs->file->bs->supported_write_flags); 513 bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED | 514 ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) & 515 bs->file->bs->supported_zero_flags); 516 ret = -EINVAL; 517 518 /* Set alignment overrides */ 519 s->align = qemu_opt_get_size(opts, "align", 0); 520 if (s->align && (s->align >= INT_MAX || !is_power_of_2(s->align))) { 521 error_setg(errp, "Cannot meet constraints with align %" PRIu64, 522 s->align); 523 goto out; 524 } 525 align = MAX(s->align, bs->file->bs->bl.request_alignment); 526 527 s->max_transfer = qemu_opt_get_size(opts, "max-transfer", 0); 528 if (s->max_transfer && 529 (s->max_transfer >= INT_MAX || 530 !QEMU_IS_ALIGNED(s->max_transfer, align))) { 531 error_setg(errp, "Cannot meet constraints with max-transfer %" PRIu64, 532 s->max_transfer); 533 goto out; 534 } 535 536 s->opt_write_zero = qemu_opt_get_size(opts, "opt-write-zero", 0); 537 if (s->opt_write_zero && 538 (s->opt_write_zero >= INT_MAX || 539 !QEMU_IS_ALIGNED(s->opt_write_zero, align))) { 540 error_setg(errp, "Cannot meet constraints with opt-write-zero %" PRIu64, 541 s->opt_write_zero); 542 goto out; 543 } 544 545 s->max_write_zero = qemu_opt_get_size(opts, "max-write-zero", 0); 546 if (s->max_write_zero && 547 (s->max_write_zero >= INT_MAX || 548 !QEMU_IS_ALIGNED(s->max_write_zero, 549 MAX(s->opt_write_zero, align)))) { 550 error_setg(errp, "Cannot meet constraints with max-write-zero %" PRIu64, 551 s->max_write_zero); 552 goto out; 553 } 554 555 s->opt_discard = qemu_opt_get_size(opts, "opt-discard", 0); 556 if (s->opt_discard && 557 (s->opt_discard >= INT_MAX || 558 !QEMU_IS_ALIGNED(s->opt_discard, align))) { 559 error_setg(errp, "Cannot meet constraints with opt-discard %" PRIu64, 560 s->opt_discard); 561 goto out; 562 } 563 564 s->max_discard = qemu_opt_get_size(opts, "max-discard", 0); 565 if (s->max_discard && 566 (s->max_discard >= INT_MAX || 567 !QEMU_IS_ALIGNED(s->max_discard, 568 MAX(s->opt_discard, align)))) { 569 error_setg(errp, "Cannot meet constraints with max-discard %" PRIu64, 570 s->max_discard); 571 goto out; 572 } 573 574 bdrv_debug_event(bs, BLKDBG_NONE); 575 576 ret = 0; 577 out: 578 if (ret < 0) { 579 qemu_mutex_destroy(&s->lock); 580 g_free(s->config_file); 581 } 582 qemu_opts_del(opts); 583 return ret; 584 } 585 586 static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes, 587 BlkdebugIOType iotype) 588 { 589 BDRVBlkdebugState *s = bs->opaque; 590 BlkdebugRule *rule = NULL; 591 int error; 592 bool immediately; 593 594 qemu_mutex_lock(&s->lock); 595 QSIMPLEQ_FOREACH(rule, &s->active_rules, active_next) { 596 uint64_t inject_offset = rule->options.inject.offset; 597 598 if ((inject_offset == -1 || 599 (bytes && inject_offset >= offset && 600 inject_offset < offset + bytes)) && 601 (rule->options.inject.iotype_mask & (1ull << iotype))) 602 { 603 break; 604 } 605 } 606 607 if (!rule || !rule->options.inject.error) { 608 qemu_mutex_unlock(&s->lock); 609 return 0; 610 } 611 612 immediately = rule->options.inject.immediately; 613 error = rule->options.inject.error; 614 615 if (rule->options.inject.once) { 616 QSIMPLEQ_REMOVE(&s->active_rules, rule, BlkdebugRule, active_next); 617 remove_rule(rule); 618 } 619 620 qemu_mutex_unlock(&s->lock); 621 if (!immediately) { 622 aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self()); 623 qemu_coroutine_yield(); 624 } 625 626 return -error; 627 } 628 629 static int coroutine_fn GRAPH_RDLOCK 630 blkdebug_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, 631 QEMUIOVector *qiov, BdrvRequestFlags flags) 632 { 633 int err; 634 635 /* Sanity check block layer guarantees */ 636 assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); 637 assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); 638 if (bs->bl.max_transfer) { 639 assert(bytes <= bs->bl.max_transfer); 640 } 641 642 err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_READ); 643 if (err) { 644 return err; 645 } 646 647 return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags); 648 } 649 650 static int coroutine_fn GRAPH_RDLOCK 651 blkdebug_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes, 652 QEMUIOVector *qiov, BdrvRequestFlags flags) 653 { 654 int err; 655 656 /* Sanity check block layer guarantees */ 657 assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); 658 assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); 659 if (bs->bl.max_transfer) { 660 assert(bytes <= bs->bl.max_transfer); 661 } 662 663 err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_WRITE); 664 if (err) { 665 return err; 666 } 667 668 return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags); 669 } 670 671 static int GRAPH_RDLOCK coroutine_fn blkdebug_co_flush(BlockDriverState *bs) 672 { 673 int err = rule_check(bs, 0, 0, BLKDEBUG_IO_TYPE_FLUSH); 674 675 if (err) { 676 return err; 677 } 678 679 return bdrv_co_flush(bs->file->bs); 680 } 681 682 static int coroutine_fn GRAPH_RDLOCK 683 blkdebug_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes, 684 BdrvRequestFlags flags) 685 { 686 uint32_t align = MAX(bs->bl.request_alignment, 687 bs->bl.pwrite_zeroes_alignment); 688 int err; 689 690 /* Only pass through requests that are larger than requested 691 * preferred alignment (so that we test the fallback to writes on 692 * unaligned portions), and check that the block layer never hands 693 * us anything unaligned that crosses an alignment boundary. */ 694 if (bytes < align) { 695 assert(QEMU_IS_ALIGNED(offset, align) || 696 QEMU_IS_ALIGNED(offset + bytes, align) || 697 DIV_ROUND_UP(offset, align) == 698 DIV_ROUND_UP(offset + bytes, align)); 699 return -ENOTSUP; 700 } 701 assert(QEMU_IS_ALIGNED(offset, align)); 702 assert(QEMU_IS_ALIGNED(bytes, align)); 703 if (bs->bl.max_pwrite_zeroes) { 704 assert(bytes <= bs->bl.max_pwrite_zeroes); 705 } 706 707 err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_WRITE_ZEROES); 708 if (err) { 709 return err; 710 } 711 712 return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags); 713 } 714 715 static int coroutine_fn GRAPH_RDLOCK 716 blkdebug_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes) 717 { 718 uint32_t align = bs->bl.pdiscard_alignment; 719 int err; 720 721 /* Only pass through requests that are larger than requested 722 * minimum alignment, and ensure that unaligned requests do not 723 * cross optimum discard boundaries. */ 724 if (bytes < bs->bl.request_alignment) { 725 assert(QEMU_IS_ALIGNED(offset, align) || 726 QEMU_IS_ALIGNED(offset + bytes, align) || 727 DIV_ROUND_UP(offset, align) == 728 DIV_ROUND_UP(offset + bytes, align)); 729 return -ENOTSUP; 730 } 731 assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)); 732 assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment)); 733 if (align && bytes >= align) { 734 assert(QEMU_IS_ALIGNED(offset, align)); 735 assert(QEMU_IS_ALIGNED(bytes, align)); 736 } 737 if (bs->bl.max_pdiscard) { 738 assert(bytes <= bs->bl.max_pdiscard); 739 } 740 741 err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_DISCARD); 742 if (err) { 743 return err; 744 } 745 746 return bdrv_co_pdiscard(bs->file, offset, bytes); 747 } 748 749 static int coroutine_fn blkdebug_co_block_status(BlockDriverState *bs, 750 bool want_zero, 751 int64_t offset, 752 int64_t bytes, 753 int64_t *pnum, 754 int64_t *map, 755 BlockDriverState **file) 756 { 757 int err; 758 759 assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); 760 761 err = rule_check(bs, offset, bytes, BLKDEBUG_IO_TYPE_BLOCK_STATUS); 762 if (err) { 763 return err; 764 } 765 766 assert(bs->file && bs->file->bs); 767 *pnum = bytes; 768 *map = offset; 769 *file = bs->file->bs; 770 return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID; 771 } 772 773 static void blkdebug_close(BlockDriverState *bs) 774 { 775 BDRVBlkdebugState *s = bs->opaque; 776 BlkdebugRule *rule, *next; 777 int i; 778 779 for (i = 0; i < BLKDBG__MAX; i++) { 780 QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) { 781 remove_rule(rule); 782 } 783 } 784 785 g_free(s->config_file); 786 qemu_mutex_destroy(&s->lock); 787 } 788 789 /* Called with lock held. */ 790 static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule) 791 { 792 BDRVBlkdebugState *s = bs->opaque; 793 BlkdebugSuspendedReq *r; 794 795 r = g_new(BlkdebugSuspendedReq, 1); 796 797 r->co = qemu_coroutine_self(); 798 r->tag = g_strdup(rule->options.suspend.tag); 799 800 remove_rule(rule); 801 QLIST_INSERT_HEAD(&s->suspended_reqs, r, next); 802 803 if (!qtest_enabled()) { 804 printf("blkdebug: Suspended request '%s'\n", r->tag); 805 } 806 } 807 808 /* Called with lock held. */ 809 static void process_rule(BlockDriverState *bs, struct BlkdebugRule *rule, 810 int *action_count, int *new_state) 811 { 812 BDRVBlkdebugState *s = bs->opaque; 813 814 /* Only process rules for the current state */ 815 if (rule->state && rule->state != s->state) { 816 return; 817 } 818 819 /* Take the action */ 820 action_count[rule->action]++; 821 switch (rule->action) { 822 case ACTION_INJECT_ERROR: 823 if (action_count[ACTION_INJECT_ERROR] == 1) { 824 QSIMPLEQ_INIT(&s->active_rules); 825 } 826 QSIMPLEQ_INSERT_HEAD(&s->active_rules, rule, active_next); 827 break; 828 829 case ACTION_SET_STATE: 830 *new_state = rule->options.set_state.new_state; 831 break; 832 833 case ACTION_SUSPEND: 834 suspend_request(bs, rule); 835 break; 836 } 837 } 838 839 static void coroutine_fn 840 blkdebug_co_debug_event(BlockDriverState *bs, BlkdebugEvent event) 841 { 842 BDRVBlkdebugState *s = bs->opaque; 843 struct BlkdebugRule *rule, *next; 844 int new_state; 845 int actions_count[ACTION__MAX] = { 0 }; 846 847 assert((int)event >= 0 && event < BLKDBG__MAX); 848 849 WITH_QEMU_LOCK_GUARD(&s->lock) { 850 new_state = s->state; 851 QLIST_FOREACH_SAFE(rule, &s->rules[event], next, next) { 852 process_rule(bs, rule, actions_count, &new_state); 853 } 854 s->state = new_state; 855 } 856 857 while (actions_count[ACTION_SUSPEND] > 0) { 858 qemu_coroutine_yield(); 859 actions_count[ACTION_SUSPEND]--; 860 } 861 } 862 863 static int blkdebug_debug_breakpoint(BlockDriverState *bs, const char *event, 864 const char *tag) 865 { 866 BDRVBlkdebugState *s = bs->opaque; 867 struct BlkdebugRule *rule; 868 int blkdebug_event; 869 870 blkdebug_event = qapi_enum_parse(&BlkdebugEvent_lookup, event, -1, NULL); 871 if (blkdebug_event < 0) { 872 return -ENOENT; 873 } 874 875 rule = g_malloc(sizeof(*rule)); 876 *rule = (struct BlkdebugRule) { 877 .event = blkdebug_event, 878 .action = ACTION_SUSPEND, 879 .state = 0, 880 .options.suspend.tag = g_strdup(tag), 881 }; 882 883 qemu_mutex_lock(&s->lock); 884 QLIST_INSERT_HEAD(&s->rules[blkdebug_event], rule, next); 885 qemu_mutex_unlock(&s->lock); 886 887 return 0; 888 } 889 890 /* Called with lock held. May temporarily release lock. */ 891 static int resume_req_by_tag(BDRVBlkdebugState *s, const char *tag, bool all) 892 { 893 BlkdebugSuspendedReq *r; 894 895 retry: 896 /* 897 * No need for _SAFE, since a different coroutine can remove another node 898 * (not the current one) in this list, and when the current one is removed 899 * the iteration starts back from beginning anyways. 900 */ 901 QLIST_FOREACH(r, &s->suspended_reqs, next) { 902 if (!strcmp(r->tag, tag)) { 903 Coroutine *co = r->co; 904 905 if (!qtest_enabled()) { 906 printf("blkdebug: Resuming request '%s'\n", r->tag); 907 } 908 909 QLIST_REMOVE(r, next); 910 g_free(r->tag); 911 g_free(r); 912 913 qemu_mutex_unlock(&s->lock); 914 qemu_coroutine_enter(co); 915 qemu_mutex_lock(&s->lock); 916 917 if (all) { 918 goto retry; 919 } 920 return 0; 921 } 922 } 923 return -ENOENT; 924 } 925 926 static int blkdebug_debug_resume(BlockDriverState *bs, const char *tag) 927 { 928 BDRVBlkdebugState *s = bs->opaque; 929 QEMU_LOCK_GUARD(&s->lock); 930 return resume_req_by_tag(s, tag, false); 931 } 932 933 static int blkdebug_debug_remove_breakpoint(BlockDriverState *bs, 934 const char *tag) 935 { 936 BDRVBlkdebugState *s = bs->opaque; 937 BlkdebugRule *rule, *next; 938 int i, ret = -ENOENT; 939 940 QEMU_LOCK_GUARD(&s->lock); 941 for (i = 0; i < BLKDBG__MAX; i++) { 942 QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) { 943 if (rule->action == ACTION_SUSPEND && 944 !strcmp(rule->options.suspend.tag, tag)) { 945 remove_rule(rule); 946 ret = 0; 947 } 948 } 949 } 950 if (resume_req_by_tag(s, tag, true) == 0) { 951 ret = 0; 952 } 953 return ret; 954 } 955 956 static bool blkdebug_debug_is_suspended(BlockDriverState *bs, const char *tag) 957 { 958 BDRVBlkdebugState *s = bs->opaque; 959 BlkdebugSuspendedReq *r; 960 961 QEMU_LOCK_GUARD(&s->lock); 962 QLIST_FOREACH(r, &s->suspended_reqs, next) { 963 if (!strcmp(r->tag, tag)) { 964 return true; 965 } 966 } 967 return false; 968 } 969 970 static int64_t coroutine_fn GRAPH_RDLOCK 971 blkdebug_co_getlength(BlockDriverState *bs) 972 { 973 return bdrv_co_getlength(bs->file->bs); 974 } 975 976 static void blkdebug_refresh_filename(BlockDriverState *bs) 977 { 978 BDRVBlkdebugState *s = bs->opaque; 979 const QDictEntry *e; 980 int ret; 981 982 if (!bs->file->bs->exact_filename[0]) { 983 return; 984 } 985 986 for (e = qdict_first(bs->full_open_options); e; 987 e = qdict_next(bs->full_open_options, e)) 988 { 989 /* Real child options are under "image", but "x-image" may 990 * contain a filename */ 991 if (strcmp(qdict_entry_key(e), "config") && 992 strcmp(qdict_entry_key(e), "image") && 993 strcmp(qdict_entry_key(e), "x-image") && 994 strcmp(qdict_entry_key(e), "driver")) 995 { 996 return; 997 } 998 } 999 1000 ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 1001 "blkdebug:%s:%s", 1002 s->config_file ?: "", bs->file->bs->exact_filename); 1003 if (ret >= sizeof(bs->exact_filename)) { 1004 /* An overflow makes the filename unusable, so do not report any */ 1005 bs->exact_filename[0] = 0; 1006 } 1007 } 1008 1009 static void blkdebug_refresh_limits(BlockDriverState *bs, Error **errp) 1010 { 1011 BDRVBlkdebugState *s = bs->opaque; 1012 1013 if (s->align) { 1014 bs->bl.request_alignment = s->align; 1015 } 1016 if (s->max_transfer) { 1017 bs->bl.max_transfer = s->max_transfer; 1018 } 1019 if (s->opt_write_zero) { 1020 bs->bl.pwrite_zeroes_alignment = s->opt_write_zero; 1021 } 1022 if (s->max_write_zero) { 1023 bs->bl.max_pwrite_zeroes = s->max_write_zero; 1024 } 1025 if (s->opt_discard) { 1026 bs->bl.pdiscard_alignment = s->opt_discard; 1027 } 1028 if (s->max_discard) { 1029 bs->bl.max_pdiscard = s->max_discard; 1030 } 1031 } 1032 1033 static int blkdebug_reopen_prepare(BDRVReopenState *reopen_state, 1034 BlockReopenQueue *queue, Error **errp) 1035 { 1036 return 0; 1037 } 1038 1039 static void blkdebug_child_perm(BlockDriverState *bs, BdrvChild *c, 1040 BdrvChildRole role, 1041 BlockReopenQueue *reopen_queue, 1042 uint64_t perm, uint64_t shared, 1043 uint64_t *nperm, uint64_t *nshared) 1044 { 1045 BDRVBlkdebugState *s = bs->opaque; 1046 1047 bdrv_default_perms(bs, c, role, reopen_queue, 1048 perm, shared, nperm, nshared); 1049 1050 *nperm |= s->take_child_perms; 1051 *nshared &= ~s->unshare_child_perms; 1052 } 1053 1054 static const char *const blkdebug_strong_runtime_opts[] = { 1055 "config", 1056 "inject-error.", 1057 "set-state.", 1058 "align", 1059 "max-transfer", 1060 "opt-write-zero", 1061 "max-write-zero", 1062 "opt-discard", 1063 "max-discard", 1064 1065 NULL 1066 }; 1067 1068 static BlockDriver bdrv_blkdebug = { 1069 .format_name = "blkdebug", 1070 .protocol_name = "blkdebug", 1071 .instance_size = sizeof(BDRVBlkdebugState), 1072 .is_filter = true, 1073 1074 .bdrv_parse_filename = blkdebug_parse_filename, 1075 .bdrv_file_open = blkdebug_open, 1076 .bdrv_close = blkdebug_close, 1077 .bdrv_reopen_prepare = blkdebug_reopen_prepare, 1078 .bdrv_child_perm = blkdebug_child_perm, 1079 1080 .bdrv_co_getlength = blkdebug_co_getlength, 1081 .bdrv_refresh_filename = blkdebug_refresh_filename, 1082 .bdrv_refresh_limits = blkdebug_refresh_limits, 1083 1084 .bdrv_co_preadv = blkdebug_co_preadv, 1085 .bdrv_co_pwritev = blkdebug_co_pwritev, 1086 .bdrv_co_flush_to_disk = blkdebug_co_flush, 1087 .bdrv_co_pwrite_zeroes = blkdebug_co_pwrite_zeroes, 1088 .bdrv_co_pdiscard = blkdebug_co_pdiscard, 1089 .bdrv_co_block_status = blkdebug_co_block_status, 1090 1091 .bdrv_co_debug_event = blkdebug_co_debug_event, 1092 .bdrv_debug_breakpoint = blkdebug_debug_breakpoint, 1093 .bdrv_debug_remove_breakpoint 1094 = blkdebug_debug_remove_breakpoint, 1095 .bdrv_debug_resume = blkdebug_debug_resume, 1096 .bdrv_debug_is_suspended = blkdebug_debug_is_suspended, 1097 1098 .strong_runtime_opts = blkdebug_strong_runtime_opts, 1099 }; 1100 1101 static void bdrv_blkdebug_init(void) 1102 { 1103 bdrv_register(&bdrv_blkdebug); 1104 } 1105 1106 block_init(bdrv_blkdebug_init); 1107