block/blkdebug.c

   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_int.h"
  31 #include "qemu/module.h"
  32 #include "qapi/qmp/qbool.h"
  33 #include "qapi/qmp/qdict.h"
  34 #include "qapi/qmp/qint.h"
  35 #include "qapi/qmp/qstring.h"
  36 #include "sysemu/qtest.h"
  37
  38 typedef struct BDRVBlkdebugState {
  39     int state;
  40     int new_state;
  41     uint64_t align;
  42     uint64_t max_transfer;
  43     uint64_t opt_write_zero;
  44     uint64_t max_write_zero;
  45     uint64_t opt_discard;
  46     uint64_t max_discard;
  47
  48     /* For blkdebug_refresh_filename() */
  49     char *config_file;
  50
  51     QLIST_HEAD(, BlkdebugRule) rules[BLKDBG__MAX];
  52     QSIMPLEQ_HEAD(, BlkdebugRule) active_rules;
  53     QLIST_HEAD(, BlkdebugSuspendedReq) suspended_reqs;
  54 } BDRVBlkdebugState;
  55
  56 typedef struct BlkdebugAIOCB {
  57     BlockAIOCB common;
  58     int ret;
  59 } BlkdebugAIOCB;
  60
  61 typedef struct BlkdebugSuspendedReq {
  62     Coroutine *co;
  63     char *tag;
  64     QLIST_ENTRY(BlkdebugSuspendedReq) next;
  65 } BlkdebugSuspendedReq;
  66
  67 enum {
  68     ACTION_INJECT_ERROR,
  69     ACTION_SET_STATE,
  70     ACTION_SUSPEND,
  71 };
  72
  73 typedef struct BlkdebugRule {
  74     BlkdebugEvent event;
  75     int action;
  76     int state;
  77     union {
  78         struct {
  79             int error;
  80             int immediately;
  81             int once;
  82             int64_t offset;
  83         } inject;
  84         struct {
  85             int new_state;
  86         } set_state;
  87         struct {
  88             char *tag;
  89         } suspend;
  90     } options;
  91     QLIST_ENTRY(BlkdebugRule) next;
  92     QSIMPLEQ_ENTRY(BlkdebugRule) active_next;
  93 } BlkdebugRule;
  94
  95 static QemuOptsList inject_error_opts = {
  96     .name = "inject-error",
  97     .head = QTAILQ_HEAD_INITIALIZER(inject_error_opts.head),
  98     .desc = {
  99         {
 100             .name = "event",
 101             .type = QEMU_OPT_STRING,
 102         },
 103         {
 104             .name = "state",
 105             .type = QEMU_OPT_NUMBER,
 106         },
 107         {
 108             .name = "errno",
 109             .type = QEMU_OPT_NUMBER,
 110         },
 111         {
 112             .name = "sector",
 113             .type = QEMU_OPT_NUMBER,
 114         },
 115         {
 116             .name = "once",
 117             .type = QEMU_OPT_BOOL,
 118         },
 119         {
 120             .name = "immediately",
 121             .type = QEMU_OPT_BOOL,
 122         },
 123         { /* end of list */ }
 124     },
 125 };
 126
 127 static QemuOptsList set_state_opts = {
 128     .name = "set-state",
 129     .head = QTAILQ_HEAD_INITIALIZER(set_state_opts.head),
 130     .desc = {
 131         {
 132             .name = "event",
 133             .type = QEMU_OPT_STRING,
 134         },
 135         {
 136             .name = "state",
 137             .type = QEMU_OPT_NUMBER,
 138         },
 139         {
 140             .name = "new_state",
 141             .type = QEMU_OPT_NUMBER,
 142         },
 143         { /* end of list */ }
 144     },
 145 };
 146
 147 static QemuOptsList *config_groups[] = {
 148     &inject_error_opts,
 149     &set_state_opts,
 150     NULL
 151 };
 152
 153 static int get_event_by_name(const char *name, BlkdebugEvent *event)
 154 {
 155     int i;
 156
 157     for (i = 0; i < BLKDBG__MAX; i++) {
 158         if (!strcmp(BlkdebugEvent_lookup[i], name)) {
 159             *event = i;
 160             return 0;
 161         }
 162     }
 163
 164     return -1;
 165 }
 166
 167 struct add_rule_data {
 168     BDRVBlkdebugState *s;
 169     int action;
 170 };
 171
 172 static int add_rule(void *opaque, QemuOpts *opts, Error **errp)
 173 {
 174     struct add_rule_data *d = opaque;
 175     BDRVBlkdebugState *s = d->s;
 176     const char* event_name;
 177     BlkdebugEvent event;
 178     struct BlkdebugRule *rule;
 179     int64_t sector;
 180
 181     /* Find the right event for the rule */
 182     event_name = qemu_opt_get(opts, "event");
 183     if (!event_name) {
 184         error_setg(errp, "Missing event name for rule");
 185         return -1;
 186     } else if (get_event_by_name(event_name, &event) < 0) {
 187         error_setg(errp, "Invalid event name \"%s\"", event_name);
 188         return -1;
 189     }
 190
 191     /* Set attributes common for all actions */
 192     rule = g_malloc0(sizeof(*rule));
 193     *rule = (struct BlkdebugRule) {
 194         .event  = event,
 195         .action = d->action,
 196         .state  = qemu_opt_get_number(opts, "state", 0),
 197     };
 198
 199     /* Parse action-specific options */
 200     switch (d->action) {
 201     case ACTION_INJECT_ERROR:
 202         rule->options.inject.error = qemu_opt_get_number(opts, "errno", EIO);
 203         rule->options.inject.once  = qemu_opt_get_bool(opts, "once", 0);
 204         rule->options.inject.immediately =
 205             qemu_opt_get_bool(opts, "immediately", 0);
 206         sector = qemu_opt_get_number(opts, "sector", -1);
 207         rule->options.inject.offset =
 208             sector == -1 ? -1 : sector * BDRV_SECTOR_SIZE;
 209         break;
 210
 211     case ACTION_SET_STATE:
 212         rule->options.set_state.new_state =
 213             qemu_opt_get_number(opts, "new_state", 0);
 214         break;
 215
 216     case ACTION_SUSPEND:
 217         rule->options.suspend.tag =
 218             g_strdup(qemu_opt_get(opts, "tag"));
 219         break;
 220     };
 221
 222     /* Add the rule */
 223     QLIST_INSERT_HEAD(&s->rules[event], rule, next);
 224
 225     return 0;
 226 }
 227
 228 static void remove_rule(BlkdebugRule *rule)
 229 {
 230     switch (rule->action) {
 231     case ACTION_INJECT_ERROR:
 232     case ACTION_SET_STATE:
 233         break;
 234     case ACTION_SUSPEND:
 235         g_free(rule->options.suspend.tag);
 236         break;
 237     }
 238
 239     QLIST_REMOVE(rule, next);
 240     g_free(rule);
 241 }
 242
 243 static int read_config(BDRVBlkdebugState *s, const char *filename,
 244                        QDict *options, Error **errp)
 245 {
 246     FILE *f = NULL;
 247     int ret;
 248     struct add_rule_data d;
 249     Error *local_err = NULL;
 250
 251     if (filename) {
 252         f = fopen(filename, "r");
 253         if (f == NULL) {
 254             error_setg_errno(errp, errno, "Could not read blkdebug config file");
 255             return -errno;
 256         }
 257
 258         ret = qemu_config_parse(f, config_groups, filename);
 259         if (ret < 0) {
 260             error_setg(errp, "Could not parse blkdebug config file");
 261             ret = -EINVAL;
 262             goto fail;
 263         }
 264     }
 265
 266     qemu_config_parse_qdict(options, config_groups, &local_err);
 267     if (local_err) {
 268         error_propagate(errp, local_err);
 269         ret = -EINVAL;
 270         goto fail;
 271     }
 272
 273     d.s = s;
 274     d.action = ACTION_INJECT_ERROR;
 275     qemu_opts_foreach(&inject_error_opts, add_rule, &d, &local_err);
 276     if (local_err) {
 277         error_propagate(errp, local_err);
 278         ret = -EINVAL;
 279         goto fail;
 280     }
 281
 282     d.action = ACTION_SET_STATE;
 283     qemu_opts_foreach(&set_state_opts, add_rule, &d, &local_err);
 284     if (local_err) {
 285         error_propagate(errp, local_err);
 286         ret = -EINVAL;
 287         goto fail;
 288     }
 289
 290     ret = 0;
 291 fail:
 292     qemu_opts_reset(&inject_error_opts);
 293     qemu_opts_reset(&set_state_opts);
 294     if (f) {
 295         fclose(f);
 296     }
 297     return ret;
 298 }
 299
 300 /* Valid blkdebug filenames look like blkdebug:path/to/config:path/to/image */
 301 static void blkdebug_parse_filename(const char *filename, QDict *options,
 302                                     Error **errp)
 303 {
 304     const char *c;
 305
 306     /* Parse the blkdebug: prefix */
 307     if (!strstart(filename, "blkdebug:", &filename)) {
 308         /* There was no prefix; therefore, all options have to be already
 309            present in the QDict (except for the filename) */
 310         qdict_put_str(options, "x-image", filename);
 311         return;
 312     }
 313
 314     /* Parse config file path */
 315     c = strchr(filename, ':');
 316     if (c == NULL) {
 317         error_setg(errp, "blkdebug requires both config file and image path");
 318         return;
 319     }
 320
 321     if (c != filename) {
 322         QString *config_path;
 323         config_path = qstring_from_substr(filename, 0, c - filename - 1);
 324         qdict_put(options, "config", config_path);
 325     }
 326
 327     /* TODO Allow multi-level nesting and set file.filename here */
 328     filename = c + 1;
 329     qdict_put_str(options, "x-image", filename);
 330 }
 331
 332 static QemuOptsList runtime_opts = {
 333     .name = "blkdebug",
 334     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 335     .desc = {
 336         {
 337             .name = "config",
 338             .type = QEMU_OPT_STRING,
 339             .help = "Path to the configuration file",
 340         },
 341         {
 342             .name = "x-image",
 343             .type = QEMU_OPT_STRING,
 344             .help = "[internal use only, will be removed]",
 345         },
 346         {
 347             .name = "align",
 348             .type = QEMU_OPT_SIZE,
 349             .help = "Required alignment in bytes",
 350         },
 351         {
 352             .name = "max-transfer",
 353             .type = QEMU_OPT_SIZE,
 354             .help = "Maximum transfer size in bytes",
 355         },
 356         {
 357             .name = "opt-write-zero",
 358             .type = QEMU_OPT_SIZE,
 359             .help = "Optimum write zero alignment in bytes",
 360         },
 361         {
 362             .name = "max-write-zero",
 363             .type = QEMU_OPT_SIZE,
 364             .help = "Maximum write zero size in bytes",
 365         },
 366         {
 367             .name = "opt-discard",
 368             .type = QEMU_OPT_SIZE,
 369             .help = "Optimum discard alignment in bytes",
 370         },
 371         {
 372             .name = "max-discard",
 373             .type = QEMU_OPT_SIZE,
 374             .help = "Maximum discard size in bytes",
 375         },
 376         { /* end of list */ }
 377     },
 378 };
 379
 380 static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
 381                          Error **errp)
 382 {
 383     BDRVBlkdebugState *s = bs->opaque;
 384     QemuOpts *opts;
 385     Error *local_err = NULL;
 386     int ret;
 387     uint64_t align;
 388
 389     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 390     qemu_opts_absorb_qdict(opts, options, &local_err);
 391     if (local_err) {
 392         error_propagate(errp, local_err);
 393         ret = -EINVAL;
 394         goto out;
 395     }
 396
 397     /* Read rules from config file or command line options */
 398     s->config_file = g_strdup(qemu_opt_get(opts, "config"));
 399     ret = read_config(s, s->config_file, options, errp);
 400     if (ret) {
 401         goto out;
 402     }
 403
 404     /* Set initial state */
 405     s->state = 1;
 406
 407     /* Open the image file */
 408     bs->file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options, "image",
 409                                bs, &child_file, false, &local_err);
 410     if (local_err) {
 411         ret = -EINVAL;
 412         error_propagate(errp, local_err);
 413         goto out;
 414     }
 415
 416     bs->supported_write_flags = BDRV_REQ_FUA &
 417         bs->file->bs->supported_write_flags;
 418     bs->supported_zero_flags = (BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP) &
 419         bs->file->bs->supported_zero_flags;
 420     ret = -EINVAL;
 421
 422     /* Set alignment overrides */
 423     s->align = qemu_opt_get_size(opts, "align", 0);
 424     if (s->align && (s->align >= INT_MAX || !is_power_of_2(s->align))) {
 425         error_setg(errp, "Cannot meet constraints with align %" PRIu64,
 426                    s->align);
 427         goto out;
 428     }
 429     align = MAX(s->align, bs->file->bs->bl.request_alignment);
 430
 431     s->max_transfer = qemu_opt_get_size(opts, "max-transfer", 0);
 432     if (s->max_transfer &&
 433         (s->max_transfer >= INT_MAX ||
 434          !QEMU_IS_ALIGNED(s->max_transfer, align))) {
 435         error_setg(errp, "Cannot meet constraints with max-transfer %" PRIu64,
 436                    s->max_transfer);
 437         goto out;
 438     }
 439
 440     s->opt_write_zero = qemu_opt_get_size(opts, "opt-write-zero", 0);
 441     if (s->opt_write_zero &&
 442         (s->opt_write_zero >= INT_MAX ||
 443          !QEMU_IS_ALIGNED(s->opt_write_zero, align))) {
 444         error_setg(errp, "Cannot meet constraints with opt-write-zero %" PRIu64,
 445                    s->opt_write_zero);
 446         goto out;
 447     }
 448
 449     s->max_write_zero = qemu_opt_get_size(opts, "max-write-zero", 0);
 450     if (s->max_write_zero &&
 451         (s->max_write_zero >= INT_MAX ||
 452          !QEMU_IS_ALIGNED(s->max_write_zero,
 453                           MAX(s->opt_write_zero, align)))) {
 454         error_setg(errp, "Cannot meet constraints with max-write-zero %" PRIu64,
 455                    s->max_write_zero);
 456         goto out;
 457     }
 458
 459     s->opt_discard = qemu_opt_get_size(opts, "opt-discard", 0);
 460     if (s->opt_discard &&
 461         (s->opt_discard >= INT_MAX ||
 462          !QEMU_IS_ALIGNED(s->opt_discard, align))) {
 463         error_setg(errp, "Cannot meet constraints with opt-discard %" PRIu64,
 464                    s->opt_discard);
 465         goto out;
 466     }
 467
 468     s->max_discard = qemu_opt_get_size(opts, "max-discard", 0);
 469     if (s->max_discard &&
 470         (s->max_discard >= INT_MAX ||
 471          !QEMU_IS_ALIGNED(s->max_discard,
 472                           MAX(s->opt_discard, align)))) {
 473         error_setg(errp, "Cannot meet constraints with max-discard %" PRIu64,
 474                    s->max_discard);
 475         goto out;
 476     }
 477
 478     ret = 0;
 479 out:
 480     if (ret < 0) {
 481         g_free(s->config_file);
 482     }
 483     qemu_opts_del(opts);
 484     return ret;
 485 }
 486
 487 static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes)
 488 {
 489     BDRVBlkdebugState *s = bs->opaque;
 490     BlkdebugRule *rule = NULL;
 491     int error;
 492     bool immediately;
 493
 494     QSIMPLEQ_FOREACH(rule, &s->active_rules, active_next) {
 495         uint64_t inject_offset = rule->options.inject.offset;
 496
 497         if (inject_offset == -1 ||
 498             (bytes && inject_offset >= offset &&
 499              inject_offset < offset + bytes))
 500         {
 501             break;
 502         }
 503     }
 504
 505     if (!rule || !rule->options.inject.error) {
 506         return 0;
 507     }
 508
 509     immediately = rule->options.inject.immediately;
 510     error = rule->options.inject.error;
 511
 512     if (rule->options.inject.once) {
 513         QSIMPLEQ_REMOVE(&s->active_rules, rule, BlkdebugRule, active_next);
 514         remove_rule(rule);
 515     }
 516
 517     if (!immediately) {
 518         aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self());
 519         qemu_coroutine_yield();
 520     }
 521
 522     return -error;
 523 }
 524
 525 static int coroutine_fn
 526 blkdebug_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 527                    QEMUIOVector *qiov, int flags)
 528 {
 529     int err;
 530
 531     /* Sanity check block layer guarantees */
 532     assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment));
 533     assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment));
 534     if (bs->bl.max_transfer) {
 535         assert(bytes <= bs->bl.max_transfer);
 536     }
 537
 538     err = rule_check(bs, offset, bytes);
 539     if (err) {
 540         return err;
 541     }
 542
 543     return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 544 }
 545
 546 static int coroutine_fn
 547 blkdebug_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 548                     QEMUIOVector *qiov, int flags)
 549 {
 550     int err;
 551
 552     /* Sanity check block layer guarantees */
 553     assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment));
 554     assert(QEMU_IS_ALIGNED(bytes, bs->bl.request_alignment));
 555     if (bs->bl.max_transfer) {
 556         assert(bytes <= bs->bl.max_transfer);
 557     }
 558
 559     err = rule_check(bs, offset, bytes);
 560     if (err) {
 561         return err;
 562     }
 563
 564     return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 565 }
 566
 567 static int blkdebug_co_flush(BlockDriverState *bs)
 568 {
 569     int err = rule_check(bs, 0, 0);
 570
 571     if (err) {
 572         return err;
 573     }
 574
 575     return bdrv_co_flush(bs->file->bs);
 576 }
 577
 578 static int coroutine_fn blkdebug_co_pwrite_zeroes(BlockDriverState *bs,
 579                                                   int64_t offset, int count,
 580                                                   BdrvRequestFlags flags)
 581 {
 582     uint32_t align = MAX(bs->bl.request_alignment,
 583                          bs->bl.pwrite_zeroes_alignment);
 584     int err;
 585
 586     /* Only pass through requests that are larger than requested
 587      * preferred alignment (so that we test the fallback to writes on
 588      * unaligned portions), and check that the block layer never hands
 589      * us anything unaligned that crosses an alignment boundary.  */
 590     if (count < align) {
 591         assert(QEMU_IS_ALIGNED(offset, align) ||
 592                QEMU_IS_ALIGNED(offset + count, align) ||
 593                DIV_ROUND_UP(offset, align) ==
 594                DIV_ROUND_UP(offset + count, align));
 595         return -ENOTSUP;
 596     }
 597     assert(QEMU_IS_ALIGNED(offset, align));
 598     assert(QEMU_IS_ALIGNED(count, align));
 599     if (bs->bl.max_pwrite_zeroes) {
 600         assert(count <= bs->bl.max_pwrite_zeroes);
 601     }
 602
 603     err = rule_check(bs, offset, count);
 604     if (err) {
 605         return err;
 606     }
 607
 608     return bdrv_co_pwrite_zeroes(bs->file, offset, count, flags);
 609 }
 610
 611 static int coroutine_fn blkdebug_co_pdiscard(BlockDriverState *bs,
 612                                              int64_t offset, int count)
 613 {
 614     uint32_t align = bs->bl.pdiscard_alignment;
 615     int err;
 616
 617     /* Only pass through requests that are larger than requested
 618      * minimum alignment, and ensure that unaligned requests do not
 619      * cross optimum discard boundaries. */
 620     if (count < bs->bl.request_alignment) {
 621         assert(QEMU_IS_ALIGNED(offset, align) ||
 622                QEMU_IS_ALIGNED(offset + count, align) ||
 623                DIV_ROUND_UP(offset, align) ==
 624                DIV_ROUND_UP(offset + count, align));
 625         return -ENOTSUP;
 626     }
 627     assert(QEMU_IS_ALIGNED(offset, bs->bl.request_alignment));
 628     assert(QEMU_IS_ALIGNED(count, bs->bl.request_alignment));
 629     if (align && count >= align) {
 630         assert(QEMU_IS_ALIGNED(offset, align));
 631         assert(QEMU_IS_ALIGNED(count, align));
 632     }
 633     if (bs->bl.max_pdiscard) {
 634         assert(count <= bs->bl.max_pdiscard);
 635     }
 636
 637     err = rule_check(bs, offset, count);
 638     if (err) {
 639         return err;
 640     }
 641
 642     return bdrv_co_pdiscard(bs->file->bs, offset, count);
 643 }
 644
 645 static void blkdebug_close(BlockDriverState *bs)
 646 {
 647     BDRVBlkdebugState *s = bs->opaque;
 648     BlkdebugRule *rule, *next;
 649     int i;
 650
 651     for (i = 0; i < BLKDBG__MAX; i++) {
 652         QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) {
 653             remove_rule(rule);
 654         }
 655     }
 656
 657     g_free(s->config_file);
 658 }
 659
 660 static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule)
 661 {
 662     BDRVBlkdebugState *s = bs->opaque;
 663     BlkdebugSuspendedReq r;
 664
 665     r = (BlkdebugSuspendedReq) {
 666         .co         = qemu_coroutine_self(),
 667         .tag        = g_strdup(rule->options.suspend.tag),
 668     };
 669
 670     remove_rule(rule);
 671     QLIST_INSERT_HEAD(&s->suspended_reqs, &r, next);
 672
 673     if (!qtest_enabled()) {
 674         printf("blkdebug: Suspended request '%s'\n", r.tag);
 675     }
 676     qemu_coroutine_yield();
 677     if (!qtest_enabled()) {
 678         printf("blkdebug: Resuming request '%s'\n", r.tag);
 679     }
 680
 681     QLIST_REMOVE(&r, next);
 682     g_free(r.tag);
 683 }
 684
 685 static bool process_rule(BlockDriverState *bs, struct BlkdebugRule *rule,
 686     bool injected)
 687 {
 688     BDRVBlkdebugState *s = bs->opaque;
 689
 690     /* Only process rules for the current state */
 691     if (rule->state && rule->state != s->state) {
 692         return injected;
 693     }
 694
 695     /* Take the action */
 696     switch (rule->action) {
 697     case ACTION_INJECT_ERROR:
 698         if (!injected) {
 699             QSIMPLEQ_INIT(&s->active_rules);
 700             injected = true;
 701         }
 702         QSIMPLEQ_INSERT_HEAD(&s->active_rules, rule, active_next);
 703         break;
 704
 705     case ACTION_SET_STATE:
 706         s->new_state = rule->options.set_state.new_state;
 707         break;
 708
 709     case ACTION_SUSPEND:
 710         suspend_request(bs, rule);
 711         break;
 712     }
 713     return injected;
 714 }
 715
 716 static void blkdebug_debug_event(BlockDriverState *bs, BlkdebugEvent event)
 717 {
 718     BDRVBlkdebugState *s = bs->opaque;
 719     struct BlkdebugRule *rule, *next;
 720     bool injected;
 721
 722     assert((int)event >= 0 && event < BLKDBG__MAX);
 723
 724     injected = false;
 725     s->new_state = s->state;
 726     QLIST_FOREACH_SAFE(rule, &s->rules[event], next, next) {
 727         injected = process_rule(bs, rule, injected);
 728     }
 729     s->state = s->new_state;
 730 }
 731
 732 static int blkdebug_debug_breakpoint(BlockDriverState *bs, const char *event,
 733                                      const char *tag)
 734 {
 735     BDRVBlkdebugState *s = bs->opaque;
 736     struct BlkdebugRule *rule;
 737     BlkdebugEvent blkdebug_event;
 738
 739     if (get_event_by_name(event, &blkdebug_event) < 0) {
 740         return -ENOENT;
 741     }
 742
 743
 744     rule = g_malloc(sizeof(*rule));
 745     *rule = (struct BlkdebugRule) {
 746         .event  = blkdebug_event,
 747         .action = ACTION_SUSPEND,
 748         .state  = 0,
 749         .options.suspend.tag = g_strdup(tag),
 750     };
 751
 752     QLIST_INSERT_HEAD(&s->rules[blkdebug_event], rule, next);
 753
 754     return 0;
 755 }
 756
 757 static int blkdebug_debug_resume(BlockDriverState *bs, const char *tag)
 758 {
 759     BDRVBlkdebugState *s = bs->opaque;
 760     BlkdebugSuspendedReq *r, *next;
 761
 762     QLIST_FOREACH_SAFE(r, &s->suspended_reqs, next, next) {
 763         if (!strcmp(r->tag, tag)) {
 764             qemu_coroutine_enter(r->co);
 765             return 0;
 766         }
 767     }
 768     return -ENOENT;
 769 }
 770
 771 static int blkdebug_debug_remove_breakpoint(BlockDriverState *bs,
 772                                             const char *tag)
 773 {
 774     BDRVBlkdebugState *s = bs->opaque;
 775     BlkdebugSuspendedReq *r, *r_next;
 776     BlkdebugRule *rule, *next;
 777     int i, ret = -ENOENT;
 778
 779     for (i = 0; i < BLKDBG__MAX; i++) {
 780         QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) {
 781             if (rule->action == ACTION_SUSPEND &&
 782                 !strcmp(rule->options.suspend.tag, tag)) {
 783                 remove_rule(rule);
 784                 ret = 0;
 785             }
 786         }
 787     }
 788     QLIST_FOREACH_SAFE(r, &s->suspended_reqs, next, r_next) {
 789         if (!strcmp(r->tag, tag)) {
 790             qemu_coroutine_enter(r->co);
 791             ret = 0;
 792         }
 793     }
 794     return ret;
 795 }
 796
 797 static bool blkdebug_debug_is_suspended(BlockDriverState *bs, const char *tag)
 798 {
 799     BDRVBlkdebugState *s = bs->opaque;
 800     BlkdebugSuspendedReq *r;
 801
 802     QLIST_FOREACH(r, &s->suspended_reqs, next) {
 803         if (!strcmp(r->tag, tag)) {
 804             return true;
 805         }
 806     }
 807     return false;
 808 }
 809
 810 static int64_t blkdebug_getlength(BlockDriverState *bs)
 811 {
 812     return bdrv_getlength(bs->file->bs);
 813 }
 814
 815 static int blkdebug_truncate(BlockDriverState *bs, int64_t offset)
 816 {
 817     return bdrv_truncate(bs->file, offset, NULL);
 818 }
 819
 820 static void blkdebug_refresh_filename(BlockDriverState *bs, QDict *options)
 821 {
 822     BDRVBlkdebugState *s = bs->opaque;
 823     QDict *opts;
 824     const QDictEntry *e;
 825     bool force_json = false;
 826
 827     for (e = qdict_first(options); e; e = qdict_next(options, e)) {
 828         if (strcmp(qdict_entry_key(e), "config") &&
 829             strcmp(qdict_entry_key(e), "x-image"))
 830         {
 831             force_json = true;
 832             break;
 833         }
 834     }
 835
 836     if (force_json && !bs->file->bs->full_open_options) {
 837         /* The config file cannot be recreated, so creating a plain filename
 838          * is impossible */
 839         return;
 840     }
 841
 842     if (!force_json && bs->file->bs->exact_filename[0]) {
 843         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
 844                  "blkdebug:%s:%s", s->config_file ?: "",
 845                  bs->file->bs->exact_filename);
 846     }
 847
 848     opts = qdict_new();
 849     qdict_put_str(opts, "driver", "blkdebug");
 850
 851     QINCREF(bs->file->bs->full_open_options);
 852     qdict_put(opts, "image", bs->file->bs->full_open_options);
 853
 854     for (e = qdict_first(options); e; e = qdict_next(options, e)) {
 855         if (strcmp(qdict_entry_key(e), "x-image")) {
 856             qobject_incref(qdict_entry_value(e));
 857             qdict_put_obj(opts, qdict_entry_key(e), qdict_entry_value(e));
 858         }
 859     }
 860
 861     bs->full_open_options = opts;
 862 }
 863
 864 static void blkdebug_refresh_limits(BlockDriverState *bs, Error **errp)
 865 {
 866     BDRVBlkdebugState *s = bs->opaque;
 867
 868     if (s->align) {
 869         bs->bl.request_alignment = s->align;
 870     }
 871     if (s->max_transfer) {
 872         bs->bl.max_transfer = s->max_transfer;
 873     }
 874     if (s->opt_write_zero) {
 875         bs->bl.pwrite_zeroes_alignment = s->opt_write_zero;
 876     }
 877     if (s->max_write_zero) {
 878         bs->bl.max_pwrite_zeroes = s->max_write_zero;
 879     }
 880     if (s->opt_discard) {
 881         bs->bl.pdiscard_alignment = s->opt_discard;
 882     }
 883     if (s->max_discard) {
 884         bs->bl.max_pdiscard = s->max_discard;
 885     }
 886 }
 887
 888 static int blkdebug_reopen_prepare(BDRVReopenState *reopen_state,
 889                                    BlockReopenQueue *queue, Error **errp)
 890 {
 891     return 0;
 892 }
 893
 894 static BlockDriver bdrv_blkdebug = {
 895     .format_name            = "blkdebug",
 896     .protocol_name          = "blkdebug",
 897     .instance_size          = sizeof(BDRVBlkdebugState),
 898
 899     .bdrv_parse_filename    = blkdebug_parse_filename,
 900     .bdrv_file_open         = blkdebug_open,
 901     .bdrv_close             = blkdebug_close,
 902     .bdrv_reopen_prepare    = blkdebug_reopen_prepare,
 903     .bdrv_child_perm        = bdrv_filter_default_perms,
 904
 905     .bdrv_getlength         = blkdebug_getlength,
 906     .bdrv_truncate          = blkdebug_truncate,
 907     .bdrv_refresh_filename  = blkdebug_refresh_filename,
 908     .bdrv_refresh_limits    = blkdebug_refresh_limits,
 909
 910     .bdrv_co_preadv         = blkdebug_co_preadv,
 911     .bdrv_co_pwritev        = blkdebug_co_pwritev,
 912     .bdrv_co_flush_to_disk  = blkdebug_co_flush,
 913     .bdrv_co_pwrite_zeroes  = blkdebug_co_pwrite_zeroes,
 914     .bdrv_co_pdiscard       = blkdebug_co_pdiscard,
 915
 916     .bdrv_debug_event           = blkdebug_debug_event,
 917     .bdrv_debug_breakpoint      = blkdebug_debug_breakpoint,
 918     .bdrv_debug_remove_breakpoint
 919                                 = blkdebug_debug_remove_breakpoint,
 920     .bdrv_debug_resume          = blkdebug_debug_resume,
 921     .bdrv_debug_is_suspended    = blkdebug_debug_is_suspended,
 922 };
 923
 924 static void bdrv_blkdebug_init(void)
 925 {
 926     bdrv_register(&bdrv_blkdebug);
 927 }
 928
 929 block_init(bdrv_blkdebug_init);