xref: /openbmc/qemu/blockdev.c (revision ee510704a9f6c982e2740db816eeac325cc10c57)
1  /*
2   * QEMU host block devices
3   *
4   * Copyright (c) 2003-2008 Fabrice Bellard
5   *
6   * This work is licensed under the terms of the GNU GPL, version 2 or
7   * later.  See the COPYING file in the top-level directory.
8   *
9   * This file incorporates work covered by the following copyright and
10   * permission notice:
11   *
12   * Copyright (c) 2003-2008 Fabrice Bellard
13   *
14   * Permission is hereby granted, free of charge, to any person obtaining a copy
15   * of this software and associated documentation files (the "Software"), to deal
16   * in the Software without restriction, including without limitation the rights
17   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
18   * copies of the Software, and to permit persons to whom the Software is
19   * furnished to do so, subject to the following conditions:
20   *
21   * The above copyright notice and this permission notice shall be included in
22   * all copies or substantial portions of the Software.
23   *
24   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
27   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
29   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
30   * THE SOFTWARE.
31   */
32  
33  #include "qemu/osdep.h"
34  #include "sysemu/block-backend.h"
35  #include "sysemu/blockdev.h"
36  #include "hw/block/block.h"
37  #include "block/blockjob.h"
38  #include "block/dirty-bitmap.h"
39  #include "block/qdict.h"
40  #include "block/throttle-groups.h"
41  #include "monitor/monitor.h"
42  #include "qemu/error-report.h"
43  #include "qemu/option.h"
44  #include "qemu/qemu-print.h"
45  #include "qemu/config-file.h"
46  #include "qapi/qapi-commands-block.h"
47  #include "qapi/qapi-commands-transaction.h"
48  #include "qapi/qapi-visit-block-core.h"
49  #include "qapi/qmp/qdict.h"
50  #include "qapi/qmp/qnum.h"
51  #include "qapi/qmp/qstring.h"
52  #include "qapi/error.h"
53  #include "qapi/qmp/qerror.h"
54  #include "qapi/qmp/qlist.h"
55  #include "qapi/qobject-output-visitor.h"
56  #include "sysemu/sysemu.h"
57  #include "sysemu/iothread.h"
58  #include "block/block_int.h"
59  #include "block/trace.h"
60  #include "sysemu/runstate.h"
61  #include "sysemu/replay.h"
62  #include "qemu/cutils.h"
63  #include "qemu/help_option.h"
64  #include "qemu/main-loop.h"
65  #include "qemu/throttle-options.h"
66  
67  /* Protected by BQL */
68  QTAILQ_HEAD(, BlockDriverState) monitor_bdrv_states =
69      QTAILQ_HEAD_INITIALIZER(monitor_bdrv_states);
70  
71  void bdrv_set_monitor_owned(BlockDriverState *bs)
72  {
73      GLOBAL_STATE_CODE();
74      QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
75  }
76  
77  static const char *const if_name[IF_COUNT] = {
78      [IF_NONE] = "none",
79      [IF_IDE] = "ide",
80      [IF_SCSI] = "scsi",
81      [IF_FLOPPY] = "floppy",
82      [IF_PFLASH] = "pflash",
83      [IF_MTD] = "mtd",
84      [IF_SD] = "sd",
85      [IF_VIRTIO] = "virtio",
86      [IF_XEN] = "xen",
87  };
88  
89  static int if_max_devs[IF_COUNT] = {
90      /*
91       * Do not change these numbers!  They govern how drive option
92       * index maps to unit and bus.  That mapping is ABI.
93       *
94       * All controllers used to implement if=T drives need to support
95       * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
96       * Otherwise, some index values map to "impossible" bus, unit
97       * values.
98       *
99       * For instance, if you change [IF_SCSI] to 255, -drive
100       * if=scsi,index=12 no longer means bus=1,unit=5, but
101       * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
102       * the drive can't be set up.  Regression.
103       */
104      [IF_IDE] = 2,
105      [IF_SCSI] = 7,
106  };
107  
108  /**
109   * Boards may call this to offer board-by-board overrides
110   * of the default, global values.
111   */
112  void override_max_devs(BlockInterfaceType type, int max_devs)
113  {
114      BlockBackend *blk;
115      DriveInfo *dinfo;
116  
117      GLOBAL_STATE_CODE();
118  
119      if (max_devs <= 0) {
120          return;
121      }
122  
123      for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
124          dinfo = blk_legacy_dinfo(blk);
125          if (dinfo->type == type) {
126              fprintf(stderr, "Cannot override units-per-bus property of"
127                      " the %s interface, because a drive of that type has"
128                      " already been added.\n", if_name[type]);
129              g_assert_not_reached();
130          }
131      }
132  
133      if_max_devs[type] = max_devs;
134  }
135  
136  /*
137   * We automatically delete the drive when a device using it gets
138   * unplugged.  Questionable feature, but we can't just drop it.
139   * Device models call blockdev_mark_auto_del() to schedule the
140   * automatic deletion, and generic qdev code calls blockdev_auto_del()
141   * when deletion is actually safe.
142   */
143  void blockdev_mark_auto_del(BlockBackend *blk)
144  {
145      DriveInfo *dinfo = blk_legacy_dinfo(blk);
146      BlockJob *job;
147  
148      GLOBAL_STATE_CODE();
149  
150      if (!dinfo) {
151          return;
152      }
153  
154      JOB_LOCK_GUARD();
155  
156      do {
157          job = block_job_next_locked(NULL);
158          while (job && (job->job.cancelled ||
159                         job->job.deferred_to_main_loop ||
160                         !block_job_has_bdrv(job, blk_bs(blk))))
161          {
162              job = block_job_next_locked(job);
163          }
164          if (job) {
165              /*
166               * This drops the job lock temporarily and polls, so we need to
167               * restart processing the list from the start after this.
168               */
169              job_cancel_locked(&job->job, false);
170          }
171      } while (job);
172  
173      dinfo->auto_del = 1;
174  }
175  
176  void blockdev_auto_del(BlockBackend *blk)
177  {
178      DriveInfo *dinfo = blk_legacy_dinfo(blk);
179      GLOBAL_STATE_CODE();
180  
181      if (dinfo && dinfo->auto_del) {
182          monitor_remove_blk(blk);
183          blk_unref(blk);
184      }
185  }
186  
187  static int drive_index_to_bus_id(BlockInterfaceType type, int index)
188  {
189      int max_devs = if_max_devs[type];
190      return max_devs ? index / max_devs : 0;
191  }
192  
193  static int drive_index_to_unit_id(BlockInterfaceType type, int index)
194  {
195      int max_devs = if_max_devs[type];
196      return max_devs ? index % max_devs : index;
197  }
198  
199  QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
200                      const char *optstr)
201  {
202      QemuOpts *opts;
203  
204      GLOBAL_STATE_CODE();
205  
206      opts = qemu_opts_parse_noisily(qemu_find_opts("drive"), optstr, false);
207      if (!opts) {
208          return NULL;
209      }
210      if (type != IF_DEFAULT) {
211          qemu_opt_set(opts, "if", if_name[type], &error_abort);
212      }
213      if (index >= 0) {
214          qemu_opt_set_number(opts, "index", index, &error_abort);
215      }
216      if (file)
217          qemu_opt_set(opts, "file", file, &error_abort);
218      return opts;
219  }
220  
221  DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
222  {
223      BlockBackend *blk;
224      DriveInfo *dinfo;
225  
226      GLOBAL_STATE_CODE();
227  
228      for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
229          dinfo = blk_legacy_dinfo(blk);
230          if (dinfo && dinfo->type == type
231              && dinfo->bus == bus && dinfo->unit == unit) {
232              return dinfo;
233          }
234      }
235  
236      return NULL;
237  }
238  
239  /*
240   * Check board claimed all -drive that are meant to be claimed.
241   * Fatal error if any remain unclaimed.
242   */
243  void drive_check_orphaned(void)
244  {
245      BlockBackend *blk;
246      DriveInfo *dinfo;
247      Location loc;
248      bool orphans = false;
249  
250      GLOBAL_STATE_CODE();
251  
252      for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
253          dinfo = blk_legacy_dinfo(blk);
254          /*
255           * Ignore default drives, because we create certain default
256           * drives unconditionally, then leave them unclaimed.  Not the
257           * users fault.
258           * Ignore IF_VIRTIO or IF_XEN, because it gets desugared into
259           * -device, so we can leave failing to -device.
260           * Ignore IF_NONE, because leaving unclaimed IF_NONE remains
261           * available for device_add is a feature.
262           */
263          if (dinfo->is_default || dinfo->type == IF_VIRTIO
264              || dinfo->type == IF_XEN || dinfo->type == IF_NONE) {
265              continue;
266          }
267          if (!blk_get_attached_dev(blk)) {
268              loc_push_none(&loc);
269              qemu_opts_loc_restore(dinfo->opts);
270              error_report("machine type does not support"
271                           " if=%s,bus=%d,unit=%d",
272                           if_name[dinfo->type], dinfo->bus, dinfo->unit);
273              loc_pop(&loc);
274              orphans = true;
275          }
276      }
277  
278      if (orphans) {
279          exit(1);
280      }
281  }
282  
283  DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
284  {
285      GLOBAL_STATE_CODE();
286      return drive_get(type,
287                       drive_index_to_bus_id(type, index),
288                       drive_index_to_unit_id(type, index));
289  }
290  
291  int drive_get_max_bus(BlockInterfaceType type)
292  {
293      int max_bus;
294      BlockBackend *blk;
295      DriveInfo *dinfo;
296  
297      GLOBAL_STATE_CODE();
298  
299      max_bus = -1;
300      for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
301          dinfo = blk_legacy_dinfo(blk);
302          if (dinfo && dinfo->type == type && dinfo->bus > max_bus) {
303              max_bus = dinfo->bus;
304          }
305      }
306      return max_bus;
307  }
308  
309  static void bdrv_format_print(void *opaque, const char *name)
310  {
311      qemu_printf(" %s", name);
312  }
313  
314  typedef struct {
315      QEMUBH *bh;
316      BlockDriverState *bs;
317  } BDRVPutRefBH;
318  
319  static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
320  {
321      if (!strcmp(buf, "ignore")) {
322          return BLOCKDEV_ON_ERROR_IGNORE;
323      } else if (!is_read && !strcmp(buf, "enospc")) {
324          return BLOCKDEV_ON_ERROR_ENOSPC;
325      } else if (!strcmp(buf, "stop")) {
326          return BLOCKDEV_ON_ERROR_STOP;
327      } else if (!strcmp(buf, "report")) {
328          return BLOCKDEV_ON_ERROR_REPORT;
329      } else {
330          error_setg(errp, "'%s' invalid %s error action",
331                     buf, is_read ? "read" : "write");
332          return -1;
333      }
334  }
335  
336  static bool parse_stats_intervals(BlockAcctStats *stats, QList *intervals,
337                                    Error **errp)
338  {
339      const QListEntry *entry;
340      for (entry = qlist_first(intervals); entry; entry = qlist_next(entry)) {
341          switch (qobject_type(entry->value)) {
342  
343          case QTYPE_QSTRING: {
344              uint64_t length;
345              const char *str = qstring_get_str(qobject_to(QString,
346                                                           entry->value));
347              if (parse_uint_full(str, 10, &length) == 0 &&
348                  length > 0 && length <= UINT_MAX) {
349                  block_acct_add_interval(stats, (unsigned) length);
350              } else {
351                  error_setg(errp, "Invalid interval length: %s", str);
352                  return false;
353              }
354              break;
355          }
356  
357          case QTYPE_QNUM: {
358              int64_t length = qnum_get_int(qobject_to(QNum, entry->value));
359  
360              if (length > 0 && length <= UINT_MAX) {
361                  block_acct_add_interval(stats, (unsigned) length);
362              } else {
363                  error_setg(errp, "Invalid interval length: %" PRId64, length);
364                  return false;
365              }
366              break;
367          }
368  
369          default:
370              error_setg(errp, "The specification of stats-intervals is invalid");
371              return false;
372          }
373      }
374      return true;
375  }
376  
377  typedef enum { MEDIA_DISK, MEDIA_CDROM } DriveMediaType;
378  
379  /* All parameters but @opts are optional and may be set to NULL. */
380  static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
381      const char **throttling_group, ThrottleConfig *throttle_cfg,
382      BlockdevDetectZeroesOptions *detect_zeroes, Error **errp)
383  {
384      Error *local_error = NULL;
385      const char *aio;
386  
387      if (bdrv_flags) {
388          if (qemu_opt_get_bool(opts, "copy-on-read", false)) {
389              *bdrv_flags |= BDRV_O_COPY_ON_READ;
390          }
391  
392          if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
393              if (bdrv_parse_aio(aio, bdrv_flags) < 0) {
394                  error_setg(errp, "invalid aio option");
395                  return;
396              }
397          }
398      }
399  
400      /* disk I/O throttling */
401      if (throttling_group) {
402          *throttling_group = qemu_opt_get(opts, "throttling.group");
403      }
404  
405      if (throttle_cfg) {
406          throttle_config_init(throttle_cfg);
407          throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg =
408              qemu_opt_get_number(opts, "throttling.bps-total", 0);
409          throttle_cfg->buckets[THROTTLE_BPS_READ].avg  =
410              qemu_opt_get_number(opts, "throttling.bps-read", 0);
411          throttle_cfg->buckets[THROTTLE_BPS_WRITE].avg =
412              qemu_opt_get_number(opts, "throttling.bps-write", 0);
413          throttle_cfg->buckets[THROTTLE_OPS_TOTAL].avg =
414              qemu_opt_get_number(opts, "throttling.iops-total", 0);
415          throttle_cfg->buckets[THROTTLE_OPS_READ].avg =
416              qemu_opt_get_number(opts, "throttling.iops-read", 0);
417          throttle_cfg->buckets[THROTTLE_OPS_WRITE].avg =
418              qemu_opt_get_number(opts, "throttling.iops-write", 0);
419  
420          throttle_cfg->buckets[THROTTLE_BPS_TOTAL].max =
421              qemu_opt_get_number(opts, "throttling.bps-total-max", 0);
422          throttle_cfg->buckets[THROTTLE_BPS_READ].max  =
423              qemu_opt_get_number(opts, "throttling.bps-read-max", 0);
424          throttle_cfg->buckets[THROTTLE_BPS_WRITE].max =
425              qemu_opt_get_number(opts, "throttling.bps-write-max", 0);
426          throttle_cfg->buckets[THROTTLE_OPS_TOTAL].max =
427              qemu_opt_get_number(opts, "throttling.iops-total-max", 0);
428          throttle_cfg->buckets[THROTTLE_OPS_READ].max =
429              qemu_opt_get_number(opts, "throttling.iops-read-max", 0);
430          throttle_cfg->buckets[THROTTLE_OPS_WRITE].max =
431              qemu_opt_get_number(opts, "throttling.iops-write-max", 0);
432  
433          throttle_cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
434              qemu_opt_get_number(opts, "throttling.bps-total-max-length", 1);
435          throttle_cfg->buckets[THROTTLE_BPS_READ].burst_length  =
436              qemu_opt_get_number(opts, "throttling.bps-read-max-length", 1);
437          throttle_cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
438              qemu_opt_get_number(opts, "throttling.bps-write-max-length", 1);
439          throttle_cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
440              qemu_opt_get_number(opts, "throttling.iops-total-max-length", 1);
441          throttle_cfg->buckets[THROTTLE_OPS_READ].burst_length =
442              qemu_opt_get_number(opts, "throttling.iops-read-max-length", 1);
443          throttle_cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
444              qemu_opt_get_number(opts, "throttling.iops-write-max-length", 1);
445  
446          throttle_cfg->op_size =
447              qemu_opt_get_number(opts, "throttling.iops-size", 0);
448  
449          if (!throttle_is_valid(throttle_cfg, errp)) {
450              return;
451          }
452      }
453  
454      if (detect_zeroes) {
455          *detect_zeroes =
456              qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
457                              qemu_opt_get(opts, "detect-zeroes"),
458                              BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
459                              &local_error);
460          if (local_error) {
461              error_propagate(errp, local_error);
462              return;
463          }
464      }
465  }
466  
467  static OnOffAuto account_get_opt(QemuOpts *opts, const char *name)
468  {
469      if (!qemu_opt_find(opts, name)) {
470          return ON_OFF_AUTO_AUTO;
471      }
472      if (qemu_opt_get_bool(opts, name, true)) {
473          return ON_OFF_AUTO_ON;
474      }
475      return ON_OFF_AUTO_OFF;
476  }
477  
478  /* Takes the ownership of bs_opts */
479  static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
480                                     Error **errp)
481  {
482      const char *buf;
483      int bdrv_flags = 0;
484      int on_read_error, on_write_error;
485      OnOffAuto account_invalid, account_failed;
486      bool writethrough, read_only;
487      BlockBackend *blk;
488      BlockDriverState *bs;
489      ThrottleConfig cfg;
490      int snapshot = 0;
491      Error *error = NULL;
492      QemuOpts *opts;
493      QDict *interval_dict = NULL;
494      QList *interval_list = NULL;
495      const char *id;
496      BlockdevDetectZeroesOptions detect_zeroes =
497          BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
498      const char *throttling_group = NULL;
499  
500      /* Check common options by copying from bs_opts to opts, all other options
501       * stay in bs_opts for processing by bdrv_open(). */
502      id = qdict_get_try_str(bs_opts, "id");
503      opts = qemu_opts_create(&qemu_common_drive_opts, id, 1, errp);
504      if (!opts) {
505          goto err_no_opts;
506      }
507  
508      if (!qemu_opts_absorb_qdict(opts, bs_opts, errp)) {
509          goto early_err;
510      }
511  
512      if (id) {
513          qdict_del(bs_opts, "id");
514      }
515  
516      /* extract parameters */
517      snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
518  
519      account_invalid = account_get_opt(opts, "stats-account-invalid");
520      account_failed = account_get_opt(opts, "stats-account-failed");
521  
522      writethrough = !qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, true);
523  
524      id = qemu_opts_id(opts);
525  
526      qdict_extract_subqdict(bs_opts, &interval_dict, "stats-intervals.");
527      qdict_array_split(interval_dict, &interval_list);
528  
529      if (qdict_size(interval_dict) != 0) {
530          error_setg(errp, "Invalid option stats-intervals.%s",
531                     qdict_first(interval_dict)->key);
532          goto early_err;
533      }
534  
535      extract_common_blockdev_options(opts, &bdrv_flags, &throttling_group, &cfg,
536                                      &detect_zeroes, &error);
537      if (error) {
538          error_propagate(errp, error);
539          goto early_err;
540      }
541  
542      if ((buf = qemu_opt_get(opts, "format")) != NULL) {
543          if (is_help_option(buf)) {
544              qemu_printf("Supported formats:");
545              bdrv_iterate_format(bdrv_format_print, NULL, false);
546              qemu_printf("\nSupported formats (read-only):");
547              bdrv_iterate_format(bdrv_format_print, NULL, true);
548              qemu_printf("\n");
549              goto early_err;
550          }
551  
552          if (qdict_haskey(bs_opts, "driver")) {
553              error_setg(errp, "Cannot specify both 'driver' and 'format'");
554              goto early_err;
555          }
556          qdict_put_str(bs_opts, "driver", buf);
557      }
558  
559      on_write_error = BLOCKDEV_ON_ERROR_ENOSPC;
560      if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
561          on_write_error = parse_block_error_action(buf, 0, &error);
562          if (error) {
563              error_propagate(errp, error);
564              goto early_err;
565          }
566      }
567  
568      on_read_error = BLOCKDEV_ON_ERROR_REPORT;
569      if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
570          on_read_error = parse_block_error_action(buf, 1, &error);
571          if (error) {
572              error_propagate(errp, error);
573              goto early_err;
574          }
575      }
576  
577      if (snapshot) {
578          bdrv_flags |= BDRV_O_SNAPSHOT;
579      }
580  
581      read_only = qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false);
582  
583      /* init */
584      if ((!file || !*file) && !qdict_size(bs_opts)) {
585          BlockBackendRootState *blk_rs;
586  
587          blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
588          blk_rs = blk_get_root_state(blk);
589          blk_rs->open_flags    = bdrv_flags | (read_only ? 0 : BDRV_O_RDWR);
590          blk_rs->detect_zeroes = detect_zeroes;
591  
592          qobject_unref(bs_opts);
593      } else {
594          if (file && !*file) {
595              file = NULL;
596          }
597  
598          /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
599           * with other callers) rather than what we want as the real defaults.
600           * Apply the defaults here instead. */
601          qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
602          qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
603          qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY,
604                                read_only ? "on" : "off");
605          qdict_set_default_str(bs_opts, BDRV_OPT_AUTO_READ_ONLY, "on");
606          assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0);
607  
608          if (runstate_check(RUN_STATE_INMIGRATE)) {
609              bdrv_flags |= BDRV_O_INACTIVE;
610          }
611  
612          blk = blk_new_open(file, NULL, bs_opts, bdrv_flags, errp);
613          if (!blk) {
614              goto err_no_bs_opts;
615          }
616          bs = blk_bs(blk);
617  
618          bs->detect_zeroes = detect_zeroes;
619  
620          block_acct_setup(blk_get_stats(blk), account_invalid, account_failed);
621  
622          if (!parse_stats_intervals(blk_get_stats(blk), interval_list, errp)) {
623              blk_unref(blk);
624              blk = NULL;
625              goto err_no_bs_opts;
626          }
627      }
628  
629      /* disk I/O throttling */
630      if (throttle_enabled(&cfg)) {
631          if (!throttling_group) {
632              throttling_group = id;
633          }
634          blk_io_limits_enable(blk, throttling_group);
635          blk_set_io_limits(blk, &cfg);
636      }
637  
638      blk_set_enable_write_cache(blk, !writethrough);
639      blk_set_on_error(blk, on_read_error, on_write_error);
640  
641      if (!monitor_add_blk(blk, id, errp)) {
642          blk_unref(blk);
643          blk = NULL;
644          goto err_no_bs_opts;
645      }
646  
647  err_no_bs_opts:
648      qemu_opts_del(opts);
649      qobject_unref(interval_dict);
650      qobject_unref(interval_list);
651      return blk;
652  
653  early_err:
654      qemu_opts_del(opts);
655      qobject_unref(interval_dict);
656      qobject_unref(interval_list);
657  err_no_opts:
658      qobject_unref(bs_opts);
659      return NULL;
660  }
661  
662  /* Takes the ownership of bs_opts */
663  BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)
664  {
665      int bdrv_flags = 0;
666  
667      GLOBAL_STATE_CODE();
668      /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
669       * with other callers) rather than what we want as the real defaults.
670       * Apply the defaults here instead. */
671      qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
672      qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
673      qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, "off");
674  
675      if (runstate_check(RUN_STATE_INMIGRATE)) {
676          bdrv_flags |= BDRV_O_INACTIVE;
677      }
678  
679      return bdrv_open(NULL, NULL, bs_opts, bdrv_flags, errp);
680  }
681  
682  void blockdev_close_all_bdrv_states(void)
683  {
684      BlockDriverState *bs, *next_bs;
685  
686      GLOBAL_STATE_CODE();
687      QTAILQ_FOREACH_SAFE(bs, &monitor_bdrv_states, monitor_list, next_bs) {
688          bdrv_unref(bs);
689      }
690  }
691  
692  /* Iterates over the list of monitor-owned BlockDriverStates */
693  BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs)
694  {
695      GLOBAL_STATE_CODE();
696      return bs ? QTAILQ_NEXT(bs, monitor_list)
697                : QTAILQ_FIRST(&monitor_bdrv_states);
698  }
699  
700  static bool qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
701                              Error **errp)
702  {
703      const char *value;
704  
705      value = qemu_opt_get(opts, from);
706      if (value) {
707          if (qemu_opt_find(opts, to)) {
708              error_setg(errp, "'%s' and its alias '%s' can't be used at the "
709                         "same time", to, from);
710              return false;
711          }
712      }
713  
714      /* rename all items in opts */
715      while ((value = qemu_opt_get(opts, from))) {
716          qemu_opt_set(opts, to, value, &error_abort);
717          qemu_opt_unset(opts, from);
718      }
719      return true;
720  }
721  
722  QemuOptsList qemu_legacy_drive_opts = {
723      .name = "drive",
724      .head = QTAILQ_HEAD_INITIALIZER(qemu_legacy_drive_opts.head),
725      .desc = {
726          {
727              .name = "bus",
728              .type = QEMU_OPT_NUMBER,
729              .help = "bus number",
730          },{
731              .name = "unit",
732              .type = QEMU_OPT_NUMBER,
733              .help = "unit number (i.e. lun for scsi)",
734          },{
735              .name = "index",
736              .type = QEMU_OPT_NUMBER,
737              .help = "index number",
738          },{
739              .name = "media",
740              .type = QEMU_OPT_STRING,
741              .help = "media type (disk, cdrom)",
742          },{
743              .name = "if",
744              .type = QEMU_OPT_STRING,
745              .help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
746          },{
747              .name = "file",
748              .type = QEMU_OPT_STRING,
749              .help = "file name",
750          },
751  
752          /* Options that are passed on, but have special semantics with -drive */
753          {
754              .name = BDRV_OPT_READ_ONLY,
755              .type = QEMU_OPT_BOOL,
756              .help = "open drive file as read-only",
757          },{
758              .name = "rerror",
759              .type = QEMU_OPT_STRING,
760              .help = "read error action",
761          },{
762              .name = "werror",
763              .type = QEMU_OPT_STRING,
764              .help = "write error action",
765          },{
766              .name = "copy-on-read",
767              .type = QEMU_OPT_BOOL,
768              .help = "copy read data from backing file into image file",
769          },
770  
771          { /* end of list */ }
772      },
773  };
774  
775  DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type,
776                       Error **errp)
777  {
778      const char *value;
779      BlockBackend *blk;
780      DriveInfo *dinfo = NULL;
781      QDict *bs_opts;
782      QemuOpts *legacy_opts;
783      DriveMediaType media = MEDIA_DISK;
784      BlockInterfaceType type;
785      int max_devs, bus_id, unit_id, index;
786      const char *werror, *rerror;
787      bool read_only = false;
788      bool copy_on_read;
789      const char *filename;
790      int i;
791  
792      GLOBAL_STATE_CODE();
793  
794      /* Change legacy command line options into QMP ones */
795      static const struct {
796          const char *from;
797          const char *to;
798      } opt_renames[] = {
799          { "iops",           "throttling.iops-total" },
800          { "iops_rd",        "throttling.iops-read" },
801          { "iops_wr",        "throttling.iops-write" },
802  
803          { "bps",            "throttling.bps-total" },
804          { "bps_rd",         "throttling.bps-read" },
805          { "bps_wr",         "throttling.bps-write" },
806  
807          { "iops_max",       "throttling.iops-total-max" },
808          { "iops_rd_max",    "throttling.iops-read-max" },
809          { "iops_wr_max",    "throttling.iops-write-max" },
810  
811          { "bps_max",        "throttling.bps-total-max" },
812          { "bps_rd_max",     "throttling.bps-read-max" },
813          { "bps_wr_max",     "throttling.bps-write-max" },
814  
815          { "iops_size",      "throttling.iops-size" },
816  
817          { "group",          "throttling.group" },
818  
819          { "readonly",       BDRV_OPT_READ_ONLY },
820      };
821  
822      for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
823          if (!qemu_opt_rename(all_opts, opt_renames[i].from,
824                               opt_renames[i].to, errp)) {
825              return NULL;
826          }
827      }
828  
829      value = qemu_opt_get(all_opts, "cache");
830      if (value) {
831          int flags = 0;
832          bool writethrough;
833  
834          if (bdrv_parse_cache_mode(value, &flags, &writethrough) != 0) {
835              error_setg(errp, "invalid cache option");
836              return NULL;
837          }
838  
839          /* Specific options take precedence */
840          if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_WB)) {
841              qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_WB,
842                                !writethrough, &error_abort);
843          }
844          if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_DIRECT)) {
845              qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_DIRECT,
846                                !!(flags & BDRV_O_NOCACHE), &error_abort);
847          }
848          if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_NO_FLUSH)) {
849              qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_NO_FLUSH,
850                                !!(flags & BDRV_O_NO_FLUSH), &error_abort);
851          }
852          qemu_opt_unset(all_opts, "cache");
853      }
854  
855      /* Get a QDict for processing the options */
856      bs_opts = qdict_new();
857      qemu_opts_to_qdict(all_opts, bs_opts);
858  
859      legacy_opts = qemu_opts_create(&qemu_legacy_drive_opts, NULL, 0,
860                                     &error_abort);
861      if (!qemu_opts_absorb_qdict(legacy_opts, bs_opts, errp)) {
862          goto fail;
863      }
864  
865      /* Media type */
866      value = qemu_opt_get(legacy_opts, "media");
867      if (value) {
868          if (!strcmp(value, "disk")) {
869              media = MEDIA_DISK;
870          } else if (!strcmp(value, "cdrom")) {
871              media = MEDIA_CDROM;
872              read_only = true;
873          } else {
874              error_setg(errp, "'%s' invalid media", value);
875              goto fail;
876          }
877      }
878  
879      /* copy-on-read is disabled with a warning for read-only devices */
880      read_only |= qemu_opt_get_bool(legacy_opts, BDRV_OPT_READ_ONLY, false);
881      copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false);
882  
883      if (read_only && copy_on_read) {
884          warn_report("disabling copy-on-read on read-only drive");
885          copy_on_read = false;
886      }
887  
888      qdict_put_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off");
889      qdict_put_str(bs_opts, "copy-on-read", copy_on_read ? "on" : "off");
890  
891      /* Controller type */
892      value = qemu_opt_get(legacy_opts, "if");
893      if (value) {
894          for (type = 0;
895               type < IF_COUNT && strcmp(value, if_name[type]);
896               type++) {
897          }
898          if (type == IF_COUNT) {
899              error_setg(errp, "unsupported bus type '%s'", value);
900              goto fail;
901          }
902      } else {
903          type = block_default_type;
904      }
905  
906      /* Device address specified by bus/unit or index.
907       * If none was specified, try to find the first free one. */
908      bus_id  = qemu_opt_get_number(legacy_opts, "bus", 0);
909      unit_id = qemu_opt_get_number(legacy_opts, "unit", -1);
910      index   = qemu_opt_get_number(legacy_opts, "index", -1);
911  
912      max_devs = if_max_devs[type];
913  
914      if (index != -1) {
915          if (bus_id != 0 || unit_id != -1) {
916              error_setg(errp, "index cannot be used with bus and unit");
917              goto fail;
918          }
919          bus_id = drive_index_to_bus_id(type, index);
920          unit_id = drive_index_to_unit_id(type, index);
921      }
922  
923      if (unit_id == -1) {
924         unit_id = 0;
925         while (drive_get(type, bus_id, unit_id) != NULL) {
926             unit_id++;
927             if (max_devs && unit_id >= max_devs) {
928                 unit_id -= max_devs;
929                 bus_id++;
930             }
931         }
932      }
933  
934      if (max_devs && unit_id >= max_devs) {
935          error_setg(errp, "unit %d too big (max is %d)", unit_id, max_devs - 1);
936          goto fail;
937      }
938  
939      if (drive_get(type, bus_id, unit_id) != NULL) {
940          error_setg(errp, "drive with bus=%d, unit=%d (index=%d) exists",
941                     bus_id, unit_id, index);
942          goto fail;
943      }
944  
945      /* no id supplied -> create one */
946      if (qemu_opts_id(all_opts) == NULL) {
947          char *new_id;
948          const char *mediastr = "";
949          if (type == IF_IDE || type == IF_SCSI) {
950              mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
951          }
952          if (max_devs) {
953              new_id = g_strdup_printf("%s%i%s%i", if_name[type], bus_id,
954                                       mediastr, unit_id);
955          } else {
956              new_id = g_strdup_printf("%s%s%i", if_name[type],
957                                       mediastr, unit_id);
958          }
959          qdict_put_str(bs_opts, "id", new_id);
960          g_free(new_id);
961      }
962  
963      /* Add virtio block device */
964      if (type == IF_VIRTIO) {
965          QemuOpts *devopts;
966          devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
967                                     &error_abort);
968          qemu_opt_set(devopts, "driver", "virtio-blk", &error_abort);
969          qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
970                       &error_abort);
971      } else if (type == IF_XEN) {
972          QemuOpts *devopts;
973          devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
974                                     &error_abort);
975          qemu_opt_set(devopts, "driver",
976                       (media == MEDIA_CDROM) ? "xen-cdrom" : "xen-disk",
977                       &error_abort);
978          qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
979                       &error_abort);
980      }
981  
982      filename = qemu_opt_get(legacy_opts, "file");
983  
984      /* Check werror/rerror compatibility with if=... */
985      werror = qemu_opt_get(legacy_opts, "werror");
986      if (werror != NULL) {
987          if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO &&
988              type != IF_NONE) {
989              error_setg(errp, "werror is not supported by this bus type");
990              goto fail;
991          }
992          qdict_put_str(bs_opts, "werror", werror);
993      }
994  
995      rerror = qemu_opt_get(legacy_opts, "rerror");
996      if (rerror != NULL) {
997          if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI &&
998              type != IF_NONE) {
999              error_setg(errp, "rerror is not supported by this bus type");
1000              goto fail;
1001          }
1002          qdict_put_str(bs_opts, "rerror", rerror);
1003      }
1004  
1005      /* Actual block device init: Functionality shared with blockdev-add */
1006      blk = blockdev_init(filename, bs_opts, errp);
1007      bs_opts = NULL;
1008      if (!blk) {
1009          goto fail;
1010      }
1011  
1012      /* Create legacy DriveInfo */
1013      dinfo = g_malloc0(sizeof(*dinfo));
1014      dinfo->opts = all_opts;
1015  
1016      dinfo->type = type;
1017      dinfo->bus = bus_id;
1018      dinfo->unit = unit_id;
1019  
1020      blk_set_legacy_dinfo(blk, dinfo);
1021  
1022      switch(type) {
1023      case IF_IDE:
1024      case IF_SCSI:
1025      case IF_XEN:
1026      case IF_NONE:
1027          dinfo->media_cd = media == MEDIA_CDROM;
1028          break;
1029      default:
1030          break;
1031      }
1032  
1033  fail:
1034      qemu_opts_del(legacy_opts);
1035      qobject_unref(bs_opts);
1036      return dinfo;
1037  }
1038  
1039  static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp)
1040  {
1041      BlockDriverState *bs;
1042  
1043      GRAPH_RDLOCK_GUARD_MAINLOOP();
1044  
1045      bs = bdrv_lookup_bs(name, name, errp);
1046      if (bs == NULL) {
1047          return NULL;
1048      }
1049  
1050      if (!bdrv_is_root_node(bs)) {
1051          error_setg(errp, "Need a root block node");
1052          return NULL;
1053      }
1054  
1055      if (!bdrv_is_inserted(bs)) {
1056          error_setg(errp, "Device has no medium");
1057          bs = NULL;
1058      }
1059  
1060      return bs;
1061  }
1062  
1063  static void blockdev_do_action(TransactionAction *action, Error **errp)
1064  {
1065      TransactionActionList list;
1066  
1067      list.value = action;
1068      list.next = NULL;
1069      qmp_transaction(&list, NULL, errp);
1070  }
1071  
1072  void qmp_blockdev_snapshot_sync(const char *device, const char *node_name,
1073                                  const char *snapshot_file,
1074                                  const char *snapshot_node_name,
1075                                  const char *format,
1076                                  bool has_mode, NewImageMode mode, Error **errp)
1077  {
1078      BlockdevSnapshotSync snapshot = {
1079          .device = (char *) device,
1080          .node_name = (char *) node_name,
1081          .snapshot_file = (char *) snapshot_file,
1082          .snapshot_node_name = (char *) snapshot_node_name,
1083          .format = (char *) format,
1084          .has_mode = has_mode,
1085          .mode = mode,
1086      };
1087      TransactionAction action = {
1088          .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
1089          .u.blockdev_snapshot_sync.data = &snapshot,
1090      };
1091      blockdev_do_action(&action, errp);
1092  }
1093  
1094  void qmp_blockdev_snapshot(const char *node, const char *overlay,
1095                             Error **errp)
1096  {
1097      BlockdevSnapshot snapshot_data = {
1098          .node = (char *) node,
1099          .overlay = (char *) overlay
1100      };
1101      TransactionAction action = {
1102          .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT,
1103          .u.blockdev_snapshot.data = &snapshot_data,
1104      };
1105      blockdev_do_action(&action, errp);
1106  }
1107  
1108  void qmp_blockdev_snapshot_internal_sync(const char *device,
1109                                           const char *name,
1110                                           Error **errp)
1111  {
1112      BlockdevSnapshotInternal snapshot = {
1113          .device = (char *) device,
1114          .name = (char *) name
1115      };
1116      TransactionAction action = {
1117          .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
1118          .u.blockdev_snapshot_internal_sync.data = &snapshot,
1119      };
1120      blockdev_do_action(&action, errp);
1121  }
1122  
1123  SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
1124                                                           const char *id,
1125                                                           const char *name,
1126                                                           Error **errp)
1127  {
1128      BlockDriverState *bs;
1129      QEMUSnapshotInfo sn;
1130      Error *local_err = NULL;
1131      SnapshotInfo *info = NULL;
1132      int ret;
1133  
1134      GLOBAL_STATE_CODE();
1135      GRAPH_RDLOCK_GUARD_MAINLOOP();
1136  
1137      bs = qmp_get_root_bs(device, errp);
1138      if (!bs) {
1139          return NULL;
1140      }
1141  
1142      if (!id && !name) {
1143          error_setg(errp, "Name or id must be provided");
1144          return NULL;
1145      }
1146  
1147      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, errp)) {
1148          return NULL;
1149      }
1150  
1151      ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
1152      if (local_err) {
1153          error_propagate(errp, local_err);
1154          return NULL;
1155      }
1156      if (!ret) {
1157          error_setg(errp,
1158                     "Snapshot with id '%s' and name '%s' does not exist on "
1159                     "device '%s'",
1160                     STR_OR_NULL(id), STR_OR_NULL(name), device);
1161          return NULL;
1162      }
1163  
1164      bdrv_snapshot_delete(bs, id, name, &local_err);
1165      if (local_err) {
1166          error_propagate(errp, local_err);
1167          return NULL;
1168      }
1169  
1170      info = g_new0(SnapshotInfo, 1);
1171      info->id = g_strdup(sn.id_str);
1172      info->name = g_strdup(sn.name);
1173      info->date_nsec = sn.date_nsec;
1174      info->date_sec = sn.date_sec;
1175      info->vm_state_size = sn.vm_state_size;
1176      info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
1177      info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
1178      if (sn.icount != -1ULL) {
1179          info->icount = sn.icount;
1180          info->has_icount = true;
1181      }
1182  
1183      return info;
1184  }
1185  
1186  /* internal snapshot private data */
1187  typedef struct InternalSnapshotState {
1188      BlockDriverState *bs;
1189      QEMUSnapshotInfo sn;
1190      bool created;
1191  } InternalSnapshotState;
1192  
1193  static void internal_snapshot_abort(void *opaque);
1194  static void internal_snapshot_clean(void *opaque);
1195  TransactionActionDrv internal_snapshot_drv = {
1196      .abort = internal_snapshot_abort,
1197      .clean = internal_snapshot_clean,
1198  };
1199  
1200  static void internal_snapshot_action(BlockdevSnapshotInternal *internal,
1201                                       Transaction *tran, Error **errp)
1202  {
1203      Error *local_err = NULL;
1204      const char *device;
1205      const char *name;
1206      BlockDriverState *bs;
1207      QEMUSnapshotInfo old_sn, *sn;
1208      bool ret;
1209      int64_t rt;
1210      InternalSnapshotState *state = g_new0(InternalSnapshotState, 1);
1211      int ret1;
1212  
1213      GLOBAL_STATE_CODE();
1214      GRAPH_RDLOCK_GUARD_MAINLOOP();
1215  
1216      tran_add(tran, &internal_snapshot_drv, state);
1217  
1218      device = internal->device;
1219      name = internal->name;
1220  
1221      bs = qmp_get_root_bs(device, errp);
1222      if (!bs) {
1223          return;
1224      }
1225  
1226      state->bs = bs;
1227  
1228      /* Paired with .clean() */
1229      bdrv_drained_begin(bs);
1230  
1231      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {
1232          return;
1233      }
1234  
1235      if (bdrv_is_read_only(bs)) {
1236          error_setg(errp, "Device '%s' is read only", device);
1237          return;
1238      }
1239  
1240      if (!bdrv_can_snapshot(bs)) {
1241          error_setg(errp, "Block format '%s' used by device '%s' "
1242                     "does not support internal snapshots",
1243                     bs->drv->format_name, device);
1244          return;
1245      }
1246  
1247      if (!strlen(name)) {
1248          error_setg(errp, "Name is empty");
1249          return;
1250      }
1251  
1252      /* check whether a snapshot with name exist */
1253      ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn,
1254                                              &local_err);
1255      if (local_err) {
1256          error_propagate(errp, local_err);
1257          return;
1258      } else if (ret) {
1259          error_setg(errp,
1260                     "Snapshot with name '%s' already exists on device '%s'",
1261                     name, device);
1262          return;
1263      }
1264  
1265      /* 3. take the snapshot */
1266      sn = &state->sn;
1267      pstrcpy(sn->name, sizeof(sn->name), name);
1268      rt = g_get_real_time();
1269      sn->date_sec = rt / G_USEC_PER_SEC;
1270      sn->date_nsec = (rt % G_USEC_PER_SEC) * 1000;
1271      sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
1272      if (replay_mode != REPLAY_MODE_NONE) {
1273          sn->icount = replay_get_current_icount();
1274      } else {
1275          sn->icount = -1ULL;
1276      }
1277  
1278      ret1 = bdrv_snapshot_create(bs, sn);
1279      if (ret1 < 0) {
1280          error_setg_errno(errp, -ret1,
1281                           "Failed to create snapshot '%s' on device '%s'",
1282                           name, device);
1283          return;
1284      }
1285  
1286      /* 4. succeed, mark a snapshot is created */
1287      state->created = true;
1288  }
1289  
1290  static void internal_snapshot_abort(void *opaque)
1291  {
1292      InternalSnapshotState *state = opaque;
1293      BlockDriverState *bs = state->bs;
1294      QEMUSnapshotInfo *sn = &state->sn;
1295      Error *local_error = NULL;
1296  
1297      GLOBAL_STATE_CODE();
1298      GRAPH_RDLOCK_GUARD_MAINLOOP();
1299  
1300      if (!state->created) {
1301          return;
1302      }
1303  
1304      if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {
1305          error_reportf_err(local_error,
1306                            "Failed to delete snapshot with id '%s' and "
1307                            "name '%s' on device '%s' in abort: ",
1308                            sn->id_str, sn->name,
1309                            bdrv_get_device_name(bs));
1310      }
1311  }
1312  
1313  static void internal_snapshot_clean(void *opaque)
1314  {
1315      g_autofree InternalSnapshotState *state = opaque;
1316  
1317      if (!state->bs) {
1318          return;
1319      }
1320  
1321      bdrv_drained_end(state->bs);
1322  }
1323  
1324  /* external snapshot private data */
1325  typedef struct ExternalSnapshotState {
1326      BlockDriverState *old_bs;
1327      BlockDriverState *new_bs;
1328      bool overlay_appended;
1329  } ExternalSnapshotState;
1330  
1331  static void external_snapshot_commit(void *opaque);
1332  static void external_snapshot_abort(void *opaque);
1333  static void external_snapshot_clean(void *opaque);
1334  TransactionActionDrv external_snapshot_drv = {
1335      .commit = external_snapshot_commit,
1336      .abort = external_snapshot_abort,
1337      .clean = external_snapshot_clean,
1338  };
1339  
1340  static void external_snapshot_action(TransactionAction *action,
1341                                       Transaction *tran, Error **errp)
1342  {
1343      int ret;
1344      int flags = 0;
1345      QDict *options = NULL;
1346      Error *local_err = NULL;
1347      /* Device and node name of the image to generate the snapshot from */
1348      const char *device;
1349      const char *node_name;
1350      /* Reference to the new image (for 'blockdev-snapshot') */
1351      const char *snapshot_ref;
1352      /* File name of the new image (for 'blockdev-snapshot-sync') */
1353      const char *new_image_file;
1354      ExternalSnapshotState *state = g_new0(ExternalSnapshotState, 1);
1355      uint64_t perm, shared;
1356  
1357      /* TODO We'll eventually have to take a writer lock in this function */
1358      GRAPH_RDLOCK_GUARD_MAINLOOP();
1359  
1360      tran_add(tran, &external_snapshot_drv, state);
1361  
1362      /* 'blockdev-snapshot' and 'blockdev-snapshot-sync' have similar
1363       * purpose but a different set of parameters */
1364      switch (action->type) {
1365      case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
1366          {
1367              BlockdevSnapshot *s = action->u.blockdev_snapshot.data;
1368              device = s->node;
1369              node_name = s->node;
1370              new_image_file = NULL;
1371              snapshot_ref = s->overlay;
1372          }
1373          break;
1374      case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
1375          {
1376              BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1377              device = s->device;
1378              node_name = s->node_name;
1379              new_image_file = s->snapshot_file;
1380              snapshot_ref = NULL;
1381          }
1382          break;
1383      default:
1384          g_assert_not_reached();
1385      }
1386  
1387      /* start processing */
1388  
1389      state->old_bs = bdrv_lookup_bs(device, node_name, errp);
1390      if (!state->old_bs) {
1391          return;
1392      }
1393  
1394      /* Paired with .clean() */
1395      bdrv_drained_begin(state->old_bs);
1396  
1397      if (!bdrv_is_inserted(state->old_bs)) {
1398          error_setg(errp, "Device '%s' has no medium",
1399                     bdrv_get_device_or_node_name(state->old_bs));
1400          return;
1401      }
1402  
1403      if (bdrv_op_is_blocked(state->old_bs,
1404                             BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
1405          return;
1406      }
1407  
1408      if (!bdrv_is_read_only(state->old_bs)) {
1409          ret = bdrv_flush(state->old_bs);
1410          if (ret < 0) {
1411              error_setg_errno(errp, -ret, "Write to node '%s' failed",
1412                               bdrv_get_device_or_node_name(state->old_bs));
1413              return;
1414          }
1415      }
1416  
1417      if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
1418          BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1419          const char *format = s->format ?: "qcow2";
1420          enum NewImageMode mode;
1421          const char *snapshot_node_name = s->snapshot_node_name;
1422  
1423          if (node_name && !snapshot_node_name) {
1424              error_setg(errp, "New overlay node-name missing");
1425              return;
1426          }
1427  
1428          if (snapshot_node_name &&
1429              bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
1430              error_setg(errp, "New overlay node-name already in use");
1431              return;
1432          }
1433  
1434          flags = state->old_bs->open_flags;
1435          flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ);
1436          flags |= BDRV_O_NO_BACKING;
1437  
1438          /* create new image w/backing file */
1439          mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1440          if (mode != NEW_IMAGE_MODE_EXISTING) {
1441              int64_t size = bdrv_getlength(state->old_bs);
1442              if (size < 0) {
1443                  error_setg_errno(errp, -size, "bdrv_getlength failed");
1444                  return;
1445              }
1446              bdrv_refresh_filename(state->old_bs);
1447  
1448              bdrv_img_create(new_image_file, format,
1449                              state->old_bs->filename,
1450                              state->old_bs->drv->format_name,
1451                              NULL, size, flags, false, &local_err);
1452  
1453              if (local_err) {
1454                  error_propagate(errp, local_err);
1455                  return;
1456              }
1457          }
1458  
1459          options = qdict_new();
1460          if (snapshot_node_name) {
1461              qdict_put_str(options, "node-name", snapshot_node_name);
1462          }
1463          qdict_put_str(options, "driver", format);
1464      }
1465  
1466      state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
1467                                errp);
1468  
1469      /* We will manually add the backing_hd field to the bs later */
1470      if (!state->new_bs) {
1471          return;
1472      }
1473  
1474      /*
1475       * Allow attaching a backing file to an overlay that's already in use only
1476       * if the parents don't assume that they are already seeing a valid image.
1477       * (Specifically, allow it as a mirror target, which is write-only access.)
1478       */
1479      bdrv_get_cumulative_perm(state->new_bs, &perm, &shared);
1480      if (perm & BLK_PERM_CONSISTENT_READ) {
1481          error_setg(errp, "The overlay is already in use");
1482          return;
1483      }
1484  
1485      if (state->new_bs->drv->is_filter) {
1486          error_setg(errp, "Filters cannot be used as overlays");
1487          return;
1488      }
1489  
1490      if (bdrv_cow_child(state->new_bs)) {
1491          error_setg(errp, "The overlay already has a backing image");
1492          return;
1493      }
1494  
1495      if (!state->new_bs->drv->supports_backing) {
1496          error_setg(errp, "The overlay does not support backing images");
1497          return;
1498      }
1499  
1500      ret = bdrv_append(state->new_bs, state->old_bs, errp);
1501      if (ret < 0) {
1502          return;
1503      }
1504      state->overlay_appended = true;
1505  }
1506  
1507  static void external_snapshot_commit(void *opaque)
1508  {
1509      ExternalSnapshotState *state = opaque;
1510  
1511      /* We don't need (or want) to use the transactional
1512       * bdrv_reopen_multiple() across all the entries at once, because we
1513       * don't want to abort all of them if one of them fails the reopen */
1514      if (!qatomic_read(&state->old_bs->copy_on_read)) {
1515          bdrv_reopen_set_read_only(state->old_bs, true, NULL);
1516      }
1517  }
1518  
1519  static void external_snapshot_abort(void *opaque)
1520  {
1521      ExternalSnapshotState *state = opaque;
1522      if (state->new_bs) {
1523          if (state->overlay_appended) {
1524              AioContext *aio_context;
1525              AioContext *tmp_context;
1526              int ret;
1527  
1528              aio_context = bdrv_get_aio_context(state->old_bs);
1529  
1530              bdrv_ref(state->old_bs);   /* we can't let bdrv_set_backind_hd()
1531                                            close state->old_bs; we need it */
1532              bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
1533  
1534              /*
1535               * The call to bdrv_set_backing_hd() above returns state->old_bs to
1536               * the main AioContext. As we're still going to be using it, return
1537               * it to the AioContext it was before.
1538               */
1539              tmp_context = bdrv_get_aio_context(state->old_bs);
1540              if (aio_context != tmp_context) {
1541                  ret = bdrv_try_change_aio_context(state->old_bs,
1542                                                    aio_context, NULL, NULL);
1543                  assert(ret == 0);
1544              }
1545  
1546              bdrv_drained_begin(state->new_bs);
1547              bdrv_graph_wrlock();
1548              bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
1549              bdrv_graph_wrunlock();
1550              bdrv_drained_end(state->new_bs);
1551  
1552              bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
1553          }
1554      }
1555  }
1556  
1557  static void external_snapshot_clean(void *opaque)
1558  {
1559      g_autofree ExternalSnapshotState *state = opaque;
1560  
1561      if (!state->old_bs) {
1562          return;
1563      }
1564  
1565      bdrv_drained_end(state->old_bs);
1566      bdrv_unref(state->new_bs);
1567  }
1568  
1569  typedef struct DriveBackupState {
1570      BlockDriverState *bs;
1571      BlockJob *job;
1572  } DriveBackupState;
1573  
1574  static BlockJob *do_backup_common(BackupCommon *backup,
1575                                    BlockDriverState *bs,
1576                                    BlockDriverState *target_bs,
1577                                    AioContext *aio_context,
1578                                    JobTxn *txn, Error **errp);
1579  
1580  static void drive_backup_commit(void *opaque);
1581  static void drive_backup_abort(void *opaque);
1582  static void drive_backup_clean(void *opaque);
1583  TransactionActionDrv drive_backup_drv = {
1584      .commit = drive_backup_commit,
1585      .abort = drive_backup_abort,
1586      .clean = drive_backup_clean,
1587  };
1588  
1589  static void drive_backup_action(DriveBackup *backup,
1590                                  JobTxn *block_job_txn,
1591                                  Transaction *tran, Error **errp)
1592  {
1593      DriveBackupState *state = g_new0(DriveBackupState, 1);
1594      BlockDriverState *bs;
1595      BlockDriverState *target_bs;
1596      BlockDriverState *source = NULL;
1597      AioContext *aio_context;
1598      const char *format;
1599      QDict *options;
1600      Error *local_err = NULL;
1601      int flags;
1602      int64_t size;
1603      bool set_backing_hd = false;
1604      int ret;
1605  
1606      GLOBAL_STATE_CODE();
1607  
1608      tran_add(tran, &drive_backup_drv, state);
1609  
1610      if (!backup->has_mode) {
1611          backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1612      }
1613  
1614      bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1615      if (!bs) {
1616          return;
1617      }
1618  
1619      if (!bs->drv) {
1620          error_setg(errp, "Device has no medium");
1621          return;
1622      }
1623  
1624      aio_context = bdrv_get_aio_context(bs);
1625  
1626      state->bs = bs;
1627      /* Paired with .clean() */
1628      bdrv_drained_begin(bs);
1629  
1630      format = backup->format;
1631      if (!format && backup->mode != NEW_IMAGE_MODE_EXISTING) {
1632          format = bs->drv->format_name;
1633      }
1634  
1635      /* Early check to avoid creating target */
1636      bdrv_graph_rdlock_main_loop();
1637      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
1638          bdrv_graph_rdunlock_main_loop();
1639          return;
1640      }
1641  
1642      flags = bs->open_flags | BDRV_O_RDWR;
1643  
1644      /*
1645       * See if we have a backing HD we can use to create our new image
1646       * on top of.
1647       */
1648      if (backup->sync == MIRROR_SYNC_MODE_TOP) {
1649          /*
1650           * Backup will not replace the source by the target, so none
1651           * of the filters skipped here will be removed (in contrast to
1652           * mirror).  Therefore, we can skip all of them when looking
1653           * for the first COW relationship.
1654           */
1655          source = bdrv_cow_bs(bdrv_skip_filters(bs));
1656          if (!source) {
1657              backup->sync = MIRROR_SYNC_MODE_FULL;
1658          }
1659      }
1660      if (backup->sync == MIRROR_SYNC_MODE_NONE) {
1661          source = bs;
1662          flags |= BDRV_O_NO_BACKING;
1663          set_backing_hd = true;
1664      }
1665      bdrv_graph_rdunlock_main_loop();
1666  
1667      size = bdrv_getlength(bs);
1668      if (size < 0) {
1669          error_setg_errno(errp, -size, "bdrv_getlength failed");
1670          return;
1671      }
1672  
1673      if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
1674          assert(format);
1675          if (source) {
1676              /* Implicit filters should not appear in the filename */
1677              BlockDriverState *explicit_backing;
1678  
1679              bdrv_graph_rdlock_main_loop();
1680              explicit_backing = bdrv_skip_implicit_filters(source);
1681              bdrv_refresh_filename(explicit_backing);
1682              bdrv_graph_rdunlock_main_loop();
1683  
1684              bdrv_img_create(backup->target, format,
1685                              explicit_backing->filename,
1686                              explicit_backing->drv->format_name, NULL,
1687                              size, flags, false, &local_err);
1688          } else {
1689              bdrv_img_create(backup->target, format, NULL, NULL, NULL,
1690                              size, flags, false, &local_err);
1691          }
1692      }
1693  
1694      if (local_err) {
1695          error_propagate(errp, local_err);
1696          return;
1697      }
1698  
1699      options = qdict_new();
1700      qdict_put_str(options, "discard", "unmap");
1701      qdict_put_str(options, "detect-zeroes", "unmap");
1702      if (format) {
1703          qdict_put_str(options, "driver", format);
1704      }
1705  
1706      target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
1707      if (!target_bs) {
1708          return;
1709      }
1710  
1711      ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1712      if (ret < 0) {
1713          bdrv_unref(target_bs);
1714          return;
1715      }
1716  
1717      if (set_backing_hd) {
1718          if (bdrv_set_backing_hd(target_bs, source, errp) < 0) {
1719              goto unref;
1720          }
1721      }
1722  
1723      state->job = do_backup_common(qapi_DriveBackup_base(backup),
1724                                    bs, target_bs, aio_context,
1725                                    block_job_txn, errp);
1726  
1727  unref:
1728      bdrv_unref(target_bs);
1729  }
1730  
1731  static void drive_backup_commit(void *opaque)
1732  {
1733      DriveBackupState *state = opaque;
1734  
1735      assert(state->job);
1736      job_start(&state->job->job);
1737  }
1738  
1739  static void drive_backup_abort(void *opaque)
1740  {
1741      DriveBackupState *state = opaque;
1742  
1743      if (state->job) {
1744          job_cancel_sync(&state->job->job, true);
1745      }
1746  }
1747  
1748  static void drive_backup_clean(void *opaque)
1749  {
1750      g_autofree DriveBackupState *state = opaque;
1751  
1752      if (!state->bs) {
1753          return;
1754      }
1755  
1756      bdrv_drained_end(state->bs);
1757  }
1758  
1759  typedef struct BlockdevBackupState {
1760      BlockDriverState *bs;
1761      BlockJob *job;
1762  } BlockdevBackupState;
1763  
1764  static void blockdev_backup_commit(void *opaque);
1765  static void blockdev_backup_abort(void *opaque);
1766  static void blockdev_backup_clean(void *opaque);
1767  TransactionActionDrv blockdev_backup_drv = {
1768      .commit = blockdev_backup_commit,
1769      .abort = blockdev_backup_abort,
1770      .clean = blockdev_backup_clean,
1771  };
1772  
1773  static void blockdev_backup_action(BlockdevBackup *backup,
1774                                     JobTxn *block_job_txn,
1775                                     Transaction *tran, Error **errp)
1776  {
1777      BlockdevBackupState *state = g_new0(BlockdevBackupState, 1);
1778      BlockDriverState *bs;
1779      BlockDriverState *target_bs;
1780      AioContext *aio_context;
1781      int ret;
1782  
1783      tran_add(tran, &blockdev_backup_drv, state);
1784  
1785      bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1786      if (!bs) {
1787          return;
1788      }
1789  
1790      target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
1791      if (!target_bs) {
1792          return;
1793      }
1794  
1795      /* Honor bdrv_try_change_aio_context() context acquisition requirements. */
1796      aio_context = bdrv_get_aio_context(bs);
1797  
1798      ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1799      if (ret < 0) {
1800          return;
1801      }
1802  
1803      state->bs = bs;
1804  
1805      /* Paired with .clean() */
1806      bdrv_drained_begin(state->bs);
1807  
1808      state->job = do_backup_common(qapi_BlockdevBackup_base(backup),
1809                                    bs, target_bs, aio_context,
1810                                    block_job_txn, errp);
1811  }
1812  
1813  static void blockdev_backup_commit(void *opaque)
1814  {
1815      BlockdevBackupState *state = opaque;
1816  
1817      assert(state->job);
1818      job_start(&state->job->job);
1819  }
1820  
1821  static void blockdev_backup_abort(void *opaque)
1822  {
1823      BlockdevBackupState *state = opaque;
1824  
1825      if (state->job) {
1826          job_cancel_sync(&state->job->job, true);
1827      }
1828  }
1829  
1830  static void blockdev_backup_clean(void *opaque)
1831  {
1832      g_autofree BlockdevBackupState *state = opaque;
1833  
1834      if (!state->bs) {
1835          return;
1836      }
1837  
1838      bdrv_drained_end(state->bs);
1839  }
1840  
1841  typedef struct BlockDirtyBitmapState {
1842      BdrvDirtyBitmap *bitmap;
1843      BlockDriverState *bs;
1844      HBitmap *backup;
1845      bool was_enabled;
1846  } BlockDirtyBitmapState;
1847  
1848  static void block_dirty_bitmap_add_abort(void *opaque);
1849  TransactionActionDrv block_dirty_bitmap_add_drv = {
1850      .abort = block_dirty_bitmap_add_abort,
1851      .clean = g_free,
1852  };
1853  
1854  static void block_dirty_bitmap_add_action(BlockDirtyBitmapAdd *action,
1855                                            Transaction *tran, Error **errp)
1856  {
1857      Error *local_err = NULL;
1858      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1859  
1860      tran_add(tran, &block_dirty_bitmap_add_drv, state);
1861  
1862      /* AIO context taken and released within qmp_block_dirty_bitmap_add */
1863      qmp_block_dirty_bitmap_add(action->node, action->name,
1864                                 action->has_granularity, action->granularity,
1865                                 action->has_persistent, action->persistent,
1866                                 action->has_disabled, action->disabled,
1867                                 &local_err);
1868  
1869      if (!local_err) {
1870          state->bitmap = block_dirty_bitmap_lookup(action->node, action->name,
1871                                                    NULL, &error_abort);
1872      } else {
1873          error_propagate(errp, local_err);
1874      }
1875  }
1876  
1877  static void block_dirty_bitmap_add_abort(void *opaque)
1878  {
1879      BlockDirtyBitmapState *state = opaque;
1880  
1881      if (state->bitmap) {
1882          bdrv_release_dirty_bitmap(state->bitmap);
1883      }
1884  }
1885  
1886  static void block_dirty_bitmap_restore(void *opaque);
1887  static void block_dirty_bitmap_free_backup(void *opaque);
1888  TransactionActionDrv block_dirty_bitmap_clear_drv = {
1889      .abort = block_dirty_bitmap_restore,
1890      .commit = block_dirty_bitmap_free_backup,
1891      .clean = g_free,
1892  };
1893  
1894  static void block_dirty_bitmap_clear_action(BlockDirtyBitmap *action,
1895                                              Transaction *tran, Error **errp)
1896  {
1897      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1898  
1899      tran_add(tran, &block_dirty_bitmap_clear_drv, state);
1900  
1901      state->bitmap = block_dirty_bitmap_lookup(action->node,
1902                                                action->name,
1903                                                &state->bs,
1904                                                errp);
1905      if (!state->bitmap) {
1906          return;
1907      }
1908  
1909      if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_DEFAULT, errp)) {
1910          return;
1911      }
1912  
1913      bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
1914  }
1915  
1916  static void block_dirty_bitmap_restore(void *opaque)
1917  {
1918      BlockDirtyBitmapState *state = opaque;
1919  
1920      if (state->backup) {
1921          bdrv_restore_dirty_bitmap(state->bitmap, state->backup);
1922      }
1923  }
1924  
1925  static void block_dirty_bitmap_free_backup(void *opaque)
1926  {
1927      BlockDirtyBitmapState *state = opaque;
1928  
1929      hbitmap_free(state->backup);
1930  }
1931  
1932  static void block_dirty_bitmap_enable_abort(void *opaque);
1933  TransactionActionDrv block_dirty_bitmap_enable_drv = {
1934      .abort = block_dirty_bitmap_enable_abort,
1935      .clean = g_free,
1936  };
1937  
1938  static void block_dirty_bitmap_enable_action(BlockDirtyBitmap *action,
1939                                               Transaction *tran, Error **errp)
1940  {
1941      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1942  
1943      tran_add(tran, &block_dirty_bitmap_enable_drv, state);
1944  
1945      state->bitmap = block_dirty_bitmap_lookup(action->node,
1946                                                action->name,
1947                                                NULL,
1948                                                errp);
1949      if (!state->bitmap) {
1950          return;
1951      }
1952  
1953      if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
1954          return;
1955      }
1956  
1957      state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
1958      bdrv_enable_dirty_bitmap(state->bitmap);
1959  }
1960  
1961  static void block_dirty_bitmap_enable_abort(void *opaque)
1962  {
1963      BlockDirtyBitmapState *state = opaque;
1964  
1965      if (!state->was_enabled) {
1966          bdrv_disable_dirty_bitmap(state->bitmap);
1967      }
1968  }
1969  
1970  static void block_dirty_bitmap_disable_abort(void *opaque);
1971  TransactionActionDrv block_dirty_bitmap_disable_drv = {
1972      .abort = block_dirty_bitmap_disable_abort,
1973      .clean = g_free,
1974  };
1975  
1976  static void block_dirty_bitmap_disable_action(BlockDirtyBitmap *action,
1977                                                Transaction *tran, Error **errp)
1978  {
1979      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1980  
1981      tran_add(tran, &block_dirty_bitmap_disable_drv, state);
1982  
1983      state->bitmap = block_dirty_bitmap_lookup(action->node,
1984                                                action->name,
1985                                                NULL,
1986                                                errp);
1987      if (!state->bitmap) {
1988          return;
1989      }
1990  
1991      if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
1992          return;
1993      }
1994  
1995      state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
1996      bdrv_disable_dirty_bitmap(state->bitmap);
1997  }
1998  
1999  static void block_dirty_bitmap_disable_abort(void *opaque)
2000  {
2001      BlockDirtyBitmapState *state = opaque;
2002  
2003      if (state->was_enabled) {
2004          bdrv_enable_dirty_bitmap(state->bitmap);
2005      }
2006  }
2007  
2008  TransactionActionDrv block_dirty_bitmap_merge_drv = {
2009      .commit = block_dirty_bitmap_free_backup,
2010      .abort = block_dirty_bitmap_restore,
2011      .clean = g_free,
2012  };
2013  
2014  static void block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge *action,
2015                                              Transaction *tran, Error **errp)
2016  {
2017      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2018  
2019      tran_add(tran, &block_dirty_bitmap_merge_drv, state);
2020  
2021      state->bitmap = block_dirty_bitmap_merge(action->node, action->target,
2022                                               action->bitmaps, &state->backup,
2023                                               errp);
2024  }
2025  
2026  static void block_dirty_bitmap_remove_commit(void *opaque);
2027  static void block_dirty_bitmap_remove_abort(void *opaque);
2028  TransactionActionDrv block_dirty_bitmap_remove_drv = {
2029      .commit = block_dirty_bitmap_remove_commit,
2030      .abort = block_dirty_bitmap_remove_abort,
2031      .clean = g_free,
2032  };
2033  
2034  static void block_dirty_bitmap_remove_action(BlockDirtyBitmap *action,
2035                                               Transaction *tran, Error **errp)
2036  {
2037      BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2038  
2039      tran_add(tran, &block_dirty_bitmap_remove_drv, state);
2040  
2041  
2042      state->bitmap = block_dirty_bitmap_remove(action->node, action->name,
2043                                                false, &state->bs, errp);
2044      if (state->bitmap) {
2045          bdrv_dirty_bitmap_skip_store(state->bitmap, true);
2046          bdrv_dirty_bitmap_set_busy(state->bitmap, true);
2047      }
2048  }
2049  
2050  static void block_dirty_bitmap_remove_abort(void *opaque)
2051  {
2052      BlockDirtyBitmapState *state = opaque;
2053  
2054      if (state->bitmap) {
2055          bdrv_dirty_bitmap_skip_store(state->bitmap, false);
2056          bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2057      }
2058  }
2059  
2060  static void block_dirty_bitmap_remove_commit(void *opaque)
2061  {
2062      BlockDirtyBitmapState *state = opaque;
2063  
2064      bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2065      bdrv_release_dirty_bitmap(state->bitmap);
2066  }
2067  
2068  static void abort_commit(void *opaque);
2069  TransactionActionDrv abort_drv = {
2070      .commit = abort_commit,
2071  };
2072  
2073  static void abort_action(Transaction *tran, Error **errp)
2074  {
2075      tran_add(tran, &abort_drv, NULL);
2076      error_setg(errp, "Transaction aborted using Abort action");
2077  }
2078  
2079  static void abort_commit(void *opaque)
2080  {
2081      g_assert_not_reached(); /* this action never succeeds */
2082  }
2083  
2084  static void transaction_action(TransactionAction *act, JobTxn *block_job_txn,
2085                                 Transaction *tran, Error **errp)
2086  {
2087      switch (act->type) {
2088      case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
2089      case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
2090          external_snapshot_action(act, tran, errp);
2091          return;
2092      case TRANSACTION_ACTION_KIND_DRIVE_BACKUP:
2093          drive_backup_action(act->u.drive_backup.data,
2094                              block_job_txn, tran, errp);
2095          return;
2096      case TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP:
2097          blockdev_backup_action(act->u.blockdev_backup.data,
2098                                 block_job_txn, tran, errp);
2099          return;
2100      case TRANSACTION_ACTION_KIND_ABORT:
2101          abort_action(tran, errp);
2102          return;
2103      case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC:
2104          internal_snapshot_action(act->u.blockdev_snapshot_internal_sync.data,
2105                                   tran, errp);
2106          return;
2107      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD:
2108          block_dirty_bitmap_add_action(act->u.block_dirty_bitmap_add.data,
2109                                        tran, errp);
2110          return;
2111      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR:
2112          block_dirty_bitmap_clear_action(act->u.block_dirty_bitmap_clear.data,
2113                                          tran, errp);
2114          return;
2115      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ENABLE:
2116          block_dirty_bitmap_enable_action(act->u.block_dirty_bitmap_enable.data,
2117                                           tran, errp);
2118          return;
2119      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_DISABLE:
2120          block_dirty_bitmap_disable_action(
2121                  act->u.block_dirty_bitmap_disable.data, tran, errp);
2122          return;
2123      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_MERGE:
2124          block_dirty_bitmap_merge_action(act->u.block_dirty_bitmap_merge.data,
2125                                          tran, errp);
2126          return;
2127      case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_REMOVE:
2128          block_dirty_bitmap_remove_action(act->u.block_dirty_bitmap_remove.data,
2129                                           tran, errp);
2130          return;
2131      /*
2132       * Where are transactions for MIRROR, COMMIT and STREAM?
2133       * Although these blockjobs use transaction callbacks like the backup job,
2134       * these jobs do not necessarily adhere to transaction semantics.
2135       * These jobs may not fully undo all of their actions on abort, nor do they
2136       * necessarily work in transactions with more than one job in them.
2137       */
2138      case TRANSACTION_ACTION_KIND__MAX:
2139      default:
2140          g_assert_not_reached();
2141      };
2142  }
2143  
2144  
2145  /*
2146   * 'Atomic' group operations.  The operations are performed as a set, and if
2147   * any fail then we roll back all operations in the group.
2148   *
2149   * Always run under BQL.
2150   */
2151  void qmp_transaction(TransactionActionList *actions,
2152                       struct TransactionProperties *properties,
2153                       Error **errp)
2154  {
2155      TransactionActionList *act;
2156      JobTxn *block_job_txn = NULL;
2157      Error *local_err = NULL;
2158      Transaction *tran;
2159      ActionCompletionMode comp_mode =
2160          properties ? properties->completion_mode :
2161          ACTION_COMPLETION_MODE_INDIVIDUAL;
2162  
2163      GLOBAL_STATE_CODE();
2164  
2165      /* Does this transaction get canceled as a group on failure?
2166       * If not, we don't really need to make a JobTxn.
2167       */
2168      if (comp_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
2169          for (act = actions; act; act = act->next) {
2170              TransactionActionKind type = act->value->type;
2171  
2172              if (type != TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP &&
2173                  type != TRANSACTION_ACTION_KIND_DRIVE_BACKUP)
2174              {
2175                  error_setg(errp,
2176                             "Action '%s' does not support transaction property "
2177                             "completion-mode = %s",
2178                             TransactionActionKind_str(type),
2179                             ActionCompletionMode_str(comp_mode));
2180                  return;
2181              }
2182          }
2183  
2184          block_job_txn = job_txn_new();
2185      }
2186  
2187      /* drain all i/o before any operations */
2188      bdrv_drain_all();
2189  
2190      tran = tran_new();
2191  
2192      /* We don't do anything in this loop that commits us to the operations */
2193      for (act = actions; act; act = act->next) {
2194          transaction_action(act->value, block_job_txn, tran, &local_err);
2195          if (local_err) {
2196              error_propagate(errp, local_err);
2197              goto delete_and_fail;
2198          }
2199      }
2200  
2201      tran_commit(tran);
2202  
2203      /* success */
2204      goto exit;
2205  
2206  delete_and_fail:
2207      /* failure, and it is all-or-none; roll back all operations */
2208      tran_abort(tran);
2209  exit:
2210      job_txn_unref(block_job_txn);
2211  }
2212  
2213  BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
2214                                                                const char *name,
2215                                                                Error **errp)
2216  {
2217      BdrvDirtyBitmap *bitmap;
2218      BlockDriverState *bs;
2219      BlockDirtyBitmapSha256 *ret = NULL;
2220      char *sha256;
2221  
2222      bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2223      if (!bitmap || !bs) {
2224          return NULL;
2225      }
2226  
2227      sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
2228      if (sha256 == NULL) {
2229          return NULL;
2230      }
2231  
2232      ret = g_new(BlockDirtyBitmapSha256, 1);
2233      ret->sha256 = sha256;
2234  
2235      return ret;
2236  }
2237  
2238  void coroutine_fn qmp_block_resize(const char *device, const char *node_name,
2239                                     int64_t size, Error **errp)
2240  {
2241      Error *local_err = NULL;
2242      BlockBackend *blk;
2243      BlockDriverState *bs;
2244      AioContext *old_ctx;
2245  
2246      bs = bdrv_lookup_bs(device, node_name, &local_err);
2247      if (local_err) {
2248          error_propagate(errp, local_err);
2249          return;
2250      }
2251  
2252      if (size < 0) {
2253          error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
2254          return;
2255      }
2256  
2257      bdrv_graph_co_rdlock();
2258      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, errp)) {
2259          bdrv_graph_co_rdunlock();
2260          return;
2261      }
2262      bdrv_graph_co_rdunlock();
2263  
2264      blk = blk_co_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
2265      if (!blk) {
2266          return;
2267      }
2268  
2269      bdrv_drained_begin(bs);
2270  
2271      old_ctx = bdrv_co_enter(bs);
2272      blk_co_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
2273      bdrv_co_leave(bs, old_ctx);
2274  
2275      bdrv_drained_end(bs);
2276      blk_co_unref(blk);
2277  }
2278  
2279  void qmp_block_stream(const char *job_id, const char *device,
2280                        const char *base,
2281                        const char *base_node,
2282                        const char *backing_file,
2283                        bool has_backing_mask_protocol,
2284                        bool backing_mask_protocol,
2285                        const char *bottom,
2286                        bool has_speed, int64_t speed,
2287                        bool has_on_error, BlockdevOnError on_error,
2288                        const char *filter_node_name,
2289                        bool has_auto_finalize, bool auto_finalize,
2290                        bool has_auto_dismiss, bool auto_dismiss,
2291                        Error **errp)
2292  {
2293      BlockDriverState *bs, *iter, *iter_end;
2294      BlockDriverState *base_bs = NULL;
2295      BlockDriverState *bottom_bs = NULL;
2296      AioContext *aio_context;
2297      Error *local_err = NULL;
2298      int job_flags = JOB_DEFAULT;
2299  
2300      GLOBAL_STATE_CODE();
2301  
2302      if (base && base_node) {
2303          error_setg(errp, "'base' and 'base-node' cannot be specified "
2304                     "at the same time");
2305          return;
2306      }
2307  
2308      if (base && bottom) {
2309          error_setg(errp, "'base' and 'bottom' cannot be specified "
2310                     "at the same time");
2311          return;
2312      }
2313  
2314      if (bottom && base_node) {
2315          error_setg(errp, "'bottom' and 'base-node' cannot be specified "
2316                     "at the same time");
2317          return;
2318      }
2319  
2320      if (!has_backing_mask_protocol) {
2321          backing_mask_protocol = false;
2322      }
2323  
2324      if (!has_on_error) {
2325          on_error = BLOCKDEV_ON_ERROR_REPORT;
2326      }
2327  
2328      bs = bdrv_lookup_bs(device, device, errp);
2329      if (!bs) {
2330          return;
2331      }
2332  
2333      aio_context = bdrv_get_aio_context(bs);
2334  
2335      bdrv_graph_rdlock_main_loop();
2336      if (base) {
2337          base_bs = bdrv_find_backing_image(bs, base);
2338          if (base_bs == NULL) {
2339              error_setg(errp, "Can't find '%s' in the backing chain", base);
2340              goto out_rdlock;
2341          }
2342          assert(bdrv_get_aio_context(base_bs) == aio_context);
2343      }
2344  
2345      if (base_node) {
2346          base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2347          if (!base_bs) {
2348              goto out_rdlock;
2349          }
2350          if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
2351              error_setg(errp, "Node '%s' is not a backing image of '%s'",
2352                         base_node, device);
2353              goto out_rdlock;
2354          }
2355          assert(bdrv_get_aio_context(base_bs) == aio_context);
2356  
2357          bdrv_refresh_filename(base_bs);
2358      }
2359  
2360      if (bottom) {
2361          bottom_bs = bdrv_lookup_bs(NULL, bottom, errp);
2362          if (!bottom_bs) {
2363              goto out_rdlock;
2364          }
2365          if (!bottom_bs->drv) {
2366              error_setg(errp, "Node '%s' is not open", bottom);
2367              goto out_rdlock;
2368          }
2369          if (bottom_bs->drv->is_filter) {
2370              error_setg(errp, "Node '%s' is a filter, use a non-filter node "
2371                         "as 'bottom'", bottom);
2372              goto out_rdlock;
2373          }
2374          if (!bdrv_chain_contains(bs, bottom_bs)) {
2375              error_setg(errp, "Node '%s' is not in a chain starting from '%s'",
2376                         bottom, device);
2377              goto out_rdlock;
2378          }
2379          assert(bdrv_get_aio_context(bottom_bs) == aio_context);
2380      }
2381  
2382      /*
2383       * Check for op blockers in the whole chain between bs and base (or bottom)
2384       */
2385      iter_end = bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
2386      for (iter = bs; iter && iter != iter_end;
2387           iter = bdrv_filter_or_cow_bs(iter))
2388      {
2389          if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
2390              goto out_rdlock;
2391          }
2392      }
2393      bdrv_graph_rdunlock_main_loop();
2394  
2395      /* if we are streaming the entire chain, the result will have no backing
2396       * file, and specifying one is therefore an error */
2397      if (!base_bs && backing_file) {
2398          error_setg(errp, "backing file specified, but streaming the "
2399                           "entire chain");
2400          return;
2401      }
2402  
2403      if (has_auto_finalize && !auto_finalize) {
2404          job_flags |= JOB_MANUAL_FINALIZE;
2405      }
2406      if (has_auto_dismiss && !auto_dismiss) {
2407          job_flags |= JOB_MANUAL_DISMISS;
2408      }
2409  
2410      stream_start(job_id, bs, base_bs, backing_file,
2411                   backing_mask_protocol,
2412                   bottom_bs, job_flags, has_speed ? speed : 0, on_error,
2413                   filter_node_name, &local_err);
2414      if (local_err) {
2415          error_propagate(errp, local_err);
2416          return;
2417      }
2418  
2419      trace_qmp_block_stream(bs);
2420      return;
2421  
2422  out_rdlock:
2423      bdrv_graph_rdunlock_main_loop();
2424  }
2425  
2426  void qmp_block_commit(const char *job_id, const char *device,
2427                        const char *base_node,
2428                        const char *base,
2429                        const char *top_node,
2430                        const char *top,
2431                        const char *backing_file,
2432                        bool has_backing_mask_protocol,
2433                        bool backing_mask_protocol,
2434                        bool has_speed, int64_t speed,
2435                        bool has_on_error, BlockdevOnError on_error,
2436                        const char *filter_node_name,
2437                        bool has_auto_finalize, bool auto_finalize,
2438                        bool has_auto_dismiss, bool auto_dismiss,
2439                        Error **errp)
2440  {
2441      BlockDriverState *bs;
2442      BlockDriverState *iter;
2443      BlockDriverState *base_bs, *top_bs;
2444      AioContext *aio_context;
2445      Error *local_err = NULL;
2446      int job_flags = JOB_DEFAULT;
2447      uint64_t top_perm, top_shared;
2448  
2449      /* TODO We'll eventually have to take a writer lock in this function */
2450      GRAPH_RDLOCK_GUARD_MAINLOOP();
2451  
2452      if (!has_speed) {
2453          speed = 0;
2454      }
2455      if (!has_on_error) {
2456          on_error = BLOCKDEV_ON_ERROR_REPORT;
2457      }
2458      if (has_auto_finalize && !auto_finalize) {
2459          job_flags |= JOB_MANUAL_FINALIZE;
2460      }
2461      if (has_auto_dismiss && !auto_dismiss) {
2462          job_flags |= JOB_MANUAL_DISMISS;
2463      }
2464      if (!has_backing_mask_protocol) {
2465          backing_mask_protocol = false;
2466      }
2467  
2468      /* Important Note:
2469       *  libvirt relies on the DeviceNotFound error class in order to probe for
2470       *  live commit feature versions; for this to work, we must make sure to
2471       *  perform the device lookup before any generic errors that may occur in a
2472       *  scenario in which all optional arguments are omitted. */
2473      bs = qmp_get_root_bs(device, &local_err);
2474      if (!bs) {
2475          bs = bdrv_lookup_bs(device, device, NULL);
2476          if (!bs) {
2477              error_free(local_err);
2478              error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
2479                        "Device '%s' not found", device);
2480          } else {
2481              error_propagate(errp, local_err);
2482          }
2483          return;
2484      }
2485  
2486      aio_context = bdrv_get_aio_context(bs);
2487  
2488      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
2489          return;
2490      }
2491  
2492      /* default top_bs is the active layer */
2493      top_bs = bs;
2494  
2495      if (top_node && top) {
2496          error_setg(errp, "'top-node' and 'top' are mutually exclusive");
2497          return;
2498      } else if (top_node) {
2499          top_bs = bdrv_lookup_bs(NULL, top_node, errp);
2500          if (top_bs == NULL) {
2501              return;
2502          }
2503          if (!bdrv_chain_contains(bs, top_bs)) {
2504              error_setg(errp, "'%s' is not in this backing file chain",
2505                         top_node);
2506              return;
2507          }
2508      } else if (top) {
2509          /* This strcmp() is just a shortcut, there is no need to
2510           * refresh @bs's filename.  If it mismatches,
2511           * bdrv_find_backing_image() will do the refresh and may still
2512           * return @bs. */
2513          if (strcmp(bs->filename, top) != 0) {
2514              top_bs = bdrv_find_backing_image(bs, top);
2515          }
2516      }
2517  
2518      if (top_bs == NULL) {
2519          error_setg(errp, "Top image file %s not found", top ? top : "NULL");
2520          return;
2521      }
2522  
2523      assert(bdrv_get_aio_context(top_bs) == aio_context);
2524  
2525      if (base_node && base) {
2526          error_setg(errp, "'base-node' and 'base' are mutually exclusive");
2527          return;
2528      } else if (base_node) {
2529          base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2530          if (base_bs == NULL) {
2531              return;
2532          }
2533          if (!bdrv_chain_contains(top_bs, base_bs)) {
2534              error_setg(errp, "'%s' is not in this backing file chain",
2535                         base_node);
2536              return;
2537          }
2538      } else if (base) {
2539          base_bs = bdrv_find_backing_image(top_bs, base);
2540          if (base_bs == NULL) {
2541              error_setg(errp, "Can't find '%s' in the backing chain", base);
2542              return;
2543          }
2544      } else {
2545          base_bs = bdrv_find_base(top_bs);
2546          if (base_bs == NULL) {
2547              error_setg(errp, "There is no backimg image");
2548              return;
2549          }
2550      }
2551  
2552      assert(bdrv_get_aio_context(base_bs) == aio_context);
2553  
2554      for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
2555           iter = bdrv_filter_or_cow_bs(iter))
2556      {
2557          if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2558              return;
2559          }
2560      }
2561  
2562      /* Do not allow attempts to commit an image into itself */
2563      if (top_bs == base_bs) {
2564          error_setg(errp, "cannot commit an image into itself");
2565          return;
2566      }
2567  
2568      /*
2569       * Active commit is required if and only if someone has taken a
2570       * WRITE permission on the top node.  Historically, we have always
2571       * used active commit for top nodes, so continue that practice
2572       * lest we possibly break clients that rely on this behavior, e.g.
2573       * to later attach this node to a writing parent.
2574       * (Active commit is never really wrong.)
2575       */
2576      bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared);
2577      if (top_perm & BLK_PERM_WRITE ||
2578          bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs))
2579      {
2580          if (backing_file) {
2581              if (bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs)) {
2582                  error_setg(errp, "'backing-file' specified,"
2583                                   " but 'top' is the active layer");
2584              } else {
2585                  error_setg(errp, "'backing-file' specified, but 'top' has a "
2586                                   "writer on it");
2587              }
2588              return;
2589          }
2590          if (!job_id) {
2591              /*
2592               * Emulate here what block_job_create() does, because it
2593               * is possible that @bs != @top_bs (the block job should
2594               * be named after @bs, even if @top_bs is the actual
2595               * source)
2596               */
2597              job_id = bdrv_get_device_name(bs);
2598          }
2599          commit_active_start(job_id, top_bs, base_bs, job_flags, speed, on_error,
2600                              filter_node_name, NULL, NULL, false, &local_err);
2601      } else {
2602          BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
2603          if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2604              return;
2605          }
2606          commit_start(job_id, bs, base_bs, top_bs, job_flags,
2607                       speed, on_error, backing_file,
2608                       backing_mask_protocol,
2609                       filter_node_name, &local_err);
2610      }
2611      if (local_err != NULL) {
2612          error_propagate(errp, local_err);
2613          return;
2614      }
2615  }
2616  
2617  /* Common QMP interface for drive-backup and blockdev-backup */
2618  static BlockJob *do_backup_common(BackupCommon *backup,
2619                                    BlockDriverState *bs,
2620                                    BlockDriverState *target_bs,
2621                                    AioContext *aio_context,
2622                                    JobTxn *txn, Error **errp)
2623  {
2624      BlockJob *job = NULL;
2625      BdrvDirtyBitmap *bmap = NULL;
2626      BackupPerf perf = { .max_workers = 64 };
2627      int job_flags = JOB_DEFAULT;
2628  
2629      if (!backup->has_speed) {
2630          backup->speed = 0;
2631      }
2632      if (!backup->has_on_source_error) {
2633          backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2634      }
2635      if (!backup->has_on_target_error) {
2636          backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2637      }
2638      if (!backup->has_auto_finalize) {
2639          backup->auto_finalize = true;
2640      }
2641      if (!backup->has_auto_dismiss) {
2642          backup->auto_dismiss = true;
2643      }
2644      if (!backup->has_compress) {
2645          backup->compress = false;
2646      }
2647  
2648      if (backup->x_perf) {
2649          if (backup->x_perf->has_use_copy_range) {
2650              perf.use_copy_range = backup->x_perf->use_copy_range;
2651          }
2652          if (backup->x_perf->has_max_workers) {
2653              perf.max_workers = backup->x_perf->max_workers;
2654          }
2655          if (backup->x_perf->has_max_chunk) {
2656              perf.max_chunk = backup->x_perf->max_chunk;
2657          }
2658          if (backup->x_perf->has_min_cluster_size) {
2659              perf.min_cluster_size = backup->x_perf->min_cluster_size;
2660          }
2661      }
2662  
2663      if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) ||
2664          (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL)) {
2665          /* done before desugaring 'incremental' to print the right message */
2666          if (!backup->bitmap) {
2667              error_setg(errp, "must provide a valid bitmap name for "
2668                         "'%s' sync mode", MirrorSyncMode_str(backup->sync));
2669              return NULL;
2670          }
2671      }
2672  
2673      if (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL) {
2674          if (backup->has_bitmap_mode &&
2675              backup->bitmap_mode != BITMAP_SYNC_MODE_ON_SUCCESS) {
2676              error_setg(errp, "Bitmap sync mode must be '%s' "
2677                         "when using sync mode '%s'",
2678                         BitmapSyncMode_str(BITMAP_SYNC_MODE_ON_SUCCESS),
2679                         MirrorSyncMode_str(backup->sync));
2680              return NULL;
2681          }
2682          backup->has_bitmap_mode = true;
2683          backup->sync = MIRROR_SYNC_MODE_BITMAP;
2684          backup->bitmap_mode = BITMAP_SYNC_MODE_ON_SUCCESS;
2685      }
2686  
2687      if (backup->bitmap) {
2688          bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
2689          if (!bmap) {
2690              error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
2691              return NULL;
2692          }
2693          if (!backup->has_bitmap_mode) {
2694              error_setg(errp, "Bitmap sync mode must be given "
2695                         "when providing a bitmap");
2696              return NULL;
2697          }
2698          if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2699              return NULL;
2700          }
2701  
2702          /* This does not produce a useful bitmap artifact: */
2703          if (backup->sync == MIRROR_SYNC_MODE_NONE) {
2704              error_setg(errp, "sync mode '%s' does not produce meaningful bitmap"
2705                         " outputs", MirrorSyncMode_str(backup->sync));
2706              return NULL;
2707          }
2708  
2709          /* If the bitmap isn't used for input or output, this is useless: */
2710          if (backup->bitmap_mode == BITMAP_SYNC_MODE_NEVER &&
2711              backup->sync != MIRROR_SYNC_MODE_BITMAP) {
2712              error_setg(errp, "Bitmap sync mode '%s' has no meaningful effect"
2713                         " when combined with sync mode '%s'",
2714                         BitmapSyncMode_str(backup->bitmap_mode),
2715                         MirrorSyncMode_str(backup->sync));
2716              return NULL;
2717          }
2718      }
2719  
2720      if (!backup->bitmap && backup->has_bitmap_mode) {
2721          error_setg(errp, "Cannot specify bitmap sync mode without a bitmap");
2722          return NULL;
2723      }
2724  
2725      if (!backup->auto_finalize) {
2726          job_flags |= JOB_MANUAL_FINALIZE;
2727      }
2728      if (!backup->auto_dismiss) {
2729          job_flags |= JOB_MANUAL_DISMISS;
2730      }
2731  
2732      job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
2733                              backup->sync, bmap, backup->bitmap_mode,
2734                              backup->compress, backup->discard_source,
2735                              backup->filter_node_name,
2736                              &perf,
2737                              backup->on_source_error,
2738                              backup->on_target_error,
2739                              job_flags, NULL, NULL, txn, errp);
2740      return job;
2741  }
2742  
2743  void qmp_drive_backup(DriveBackup *backup, Error **errp)
2744  {
2745      TransactionAction action = {
2746          .type = TRANSACTION_ACTION_KIND_DRIVE_BACKUP,
2747          .u.drive_backup.data = backup,
2748      };
2749      blockdev_do_action(&action, errp);
2750  }
2751  
2752  BlockDeviceInfoList *qmp_query_named_block_nodes(bool has_flat,
2753                                                   bool flat,
2754                                                   Error **errp)
2755  {
2756      bool return_flat = has_flat && flat;
2757  
2758      return bdrv_named_nodes_list(return_flat, errp);
2759  }
2760  
2761  XDbgBlockGraph *qmp_x_debug_query_block_graph(Error **errp)
2762  {
2763      GRAPH_RDLOCK_GUARD_MAINLOOP();
2764  
2765      return bdrv_get_xdbg_block_graph(errp);
2766  }
2767  
2768  void qmp_blockdev_backup(BlockdevBackup *backup, Error **errp)
2769  {
2770      TransactionAction action = {
2771          .type = TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP,
2772          .u.blockdev_backup.data = backup,
2773      };
2774      blockdev_do_action(&action, errp);
2775  }
2776  
2777  /* Parameter check and block job starting for drive mirroring.
2778   * Caller should hold @device and @target's aio context (must be the same).
2779   **/
2780  static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
2781                                     BlockDriverState *target,
2782                                     const char *replaces,
2783                                     enum MirrorSyncMode sync,
2784                                     BlockMirrorBackingMode backing_mode,
2785                                     bool zero_target,
2786                                     bool has_speed, int64_t speed,
2787                                     bool has_granularity, uint32_t granularity,
2788                                     bool has_buf_size, int64_t buf_size,
2789                                     bool has_on_source_error,
2790                                     BlockdevOnError on_source_error,
2791                                     bool has_on_target_error,
2792                                     BlockdevOnError on_target_error,
2793                                     bool has_unmap, bool unmap,
2794                                     const char *filter_node_name,
2795                                     bool has_copy_mode, MirrorCopyMode copy_mode,
2796                                     bool has_auto_finalize, bool auto_finalize,
2797                                     bool has_auto_dismiss, bool auto_dismiss,
2798                                     Error **errp)
2799  {
2800      BlockDriverState *unfiltered_bs;
2801      int job_flags = JOB_DEFAULT;
2802  
2803      GLOBAL_STATE_CODE();
2804      GRAPH_RDLOCK_GUARD_MAINLOOP();
2805  
2806      if (!has_speed) {
2807          speed = 0;
2808      }
2809      if (!has_on_source_error) {
2810          on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2811      }
2812      if (!has_on_target_error) {
2813          on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2814      }
2815      if (!has_granularity) {
2816          granularity = 0;
2817      }
2818      if (!has_buf_size) {
2819          buf_size = 0;
2820      }
2821      if (!has_unmap) {
2822          unmap = true;
2823      }
2824      if (!has_copy_mode) {
2825          copy_mode = MIRROR_COPY_MODE_BACKGROUND;
2826      }
2827      if (has_auto_finalize && !auto_finalize) {
2828          job_flags |= JOB_MANUAL_FINALIZE;
2829      }
2830      if (has_auto_dismiss && !auto_dismiss) {
2831          job_flags |= JOB_MANUAL_DISMISS;
2832      }
2833  
2834      if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
2835          error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2836                     "a value in range [512B, 64MB]");
2837          return;
2838      }
2839      if (granularity & (granularity - 1)) {
2840          error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2841                     "a power of 2");
2842          return;
2843      }
2844  
2845      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2846          return;
2847      }
2848      if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
2849          return;
2850      }
2851  
2852      if (!bdrv_backing_chain_next(bs) && sync == MIRROR_SYNC_MODE_TOP) {
2853          sync = MIRROR_SYNC_MODE_FULL;
2854      }
2855  
2856      if (!replaces) {
2857          /* We want to mirror from @bs, but keep implicit filters on top */
2858          unfiltered_bs = bdrv_skip_implicit_filters(bs);
2859          if (unfiltered_bs != bs) {
2860              replaces = unfiltered_bs->node_name;
2861          }
2862      }
2863  
2864      if (replaces) {
2865          BlockDriverState *to_replace_bs;
2866          int64_t bs_size, replace_size;
2867  
2868          bs_size = bdrv_getlength(bs);
2869          if (bs_size < 0) {
2870              error_setg_errno(errp, -bs_size, "Failed to query device's size");
2871              return;
2872          }
2873  
2874          to_replace_bs = check_to_replace_node(bs, replaces, errp);
2875          if (!to_replace_bs) {
2876              return;
2877          }
2878  
2879          replace_size = bdrv_getlength(to_replace_bs);
2880  
2881          if (replace_size < 0) {
2882              error_setg_errno(errp, -replace_size,
2883                               "Failed to query the replacement node's size");
2884              return;
2885          }
2886          if (bs_size != replace_size) {
2887              error_setg(errp, "cannot replace image with a mirror image of "
2888                               "different size");
2889              return;
2890          }
2891      }
2892  
2893      /* pass the node name to replace to mirror start since it's loose coupling
2894       * and will allow to check whether the node still exist at mirror completion
2895       */
2896      mirror_start(job_id, bs, target,
2897                   replaces, job_flags,
2898                   speed, granularity, buf_size, sync, backing_mode, zero_target,
2899                   on_source_error, on_target_error, unmap, filter_node_name,
2900                   copy_mode, errp);
2901  }
2902  
2903  void qmp_drive_mirror(DriveMirror *arg, Error **errp)
2904  {
2905      BlockDriverState *bs;
2906      BlockDriverState *target_backing_bs, *target_bs;
2907      AioContext *aio_context;
2908      BlockMirrorBackingMode backing_mode;
2909      Error *local_err = NULL;
2910      QDict *options = NULL;
2911      int flags;
2912      int64_t size;
2913      const char *format = arg->format;
2914      bool zero_target;
2915      int ret;
2916  
2917      bs = qmp_get_root_bs(arg->device, errp);
2918      if (!bs) {
2919          return;
2920      }
2921  
2922      /* Early check to avoid creating target */
2923      bdrv_graph_rdlock_main_loop();
2924      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2925          bdrv_graph_rdunlock_main_loop();
2926          return;
2927      }
2928  
2929      aio_context = bdrv_get_aio_context(bs);
2930  
2931      if (!arg->has_mode) {
2932          arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
2933      }
2934  
2935      if (!arg->format) {
2936          format = (arg->mode == NEW_IMAGE_MODE_EXISTING
2937                    ? NULL : bs->drv->format_name);
2938      }
2939  
2940      flags = bs->open_flags | BDRV_O_RDWR;
2941      target_backing_bs = bdrv_cow_bs(bdrv_skip_filters(bs));
2942      if (!target_backing_bs && arg->sync == MIRROR_SYNC_MODE_TOP) {
2943          arg->sync = MIRROR_SYNC_MODE_FULL;
2944      }
2945      if (arg->sync == MIRROR_SYNC_MODE_NONE) {
2946          target_backing_bs = bs;
2947      }
2948      bdrv_graph_rdunlock_main_loop();
2949  
2950      size = bdrv_getlength(bs);
2951      if (size < 0) {
2952          error_setg_errno(errp, -size, "bdrv_getlength failed");
2953          return;
2954      }
2955  
2956      if (arg->replaces) {
2957          if (!arg->node_name) {
2958              error_setg(errp, "a node-name must be provided when replacing a"
2959                               " named node of the graph");
2960              return;
2961          }
2962      }
2963  
2964      if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
2965          backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
2966      } else {
2967          backing_mode = MIRROR_OPEN_BACKING_CHAIN;
2968      }
2969  
2970      /* Don't open backing image in create() */
2971      flags |= BDRV_O_NO_BACKING;
2972  
2973      if ((arg->sync == MIRROR_SYNC_MODE_FULL || !target_backing_bs)
2974          && arg->mode != NEW_IMAGE_MODE_EXISTING)
2975      {
2976          /* create new image w/o backing file */
2977          assert(format);
2978          bdrv_img_create(arg->target, format,
2979                          NULL, NULL, NULL, size, flags, false, &local_err);
2980      } else {
2981          BlockDriverState *explicit_backing;
2982  
2983          switch (arg->mode) {
2984          case NEW_IMAGE_MODE_EXISTING:
2985              break;
2986          case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
2987              /*
2988               * Create new image with backing file.
2989               * Implicit filters should not appear in the filename.
2990               */
2991              bdrv_graph_rdlock_main_loop();
2992              explicit_backing = bdrv_skip_implicit_filters(target_backing_bs);
2993              bdrv_refresh_filename(explicit_backing);
2994              bdrv_graph_rdunlock_main_loop();
2995  
2996              bdrv_img_create(arg->target, format,
2997                              explicit_backing->filename,
2998                              explicit_backing->drv->format_name,
2999                              NULL, size, flags, false, &local_err);
3000              break;
3001          default:
3002              abort();
3003          }
3004      }
3005  
3006      if (local_err) {
3007          error_propagate(errp, local_err);
3008          return;
3009      }
3010  
3011      options = qdict_new();
3012      if (arg->node_name) {
3013          qdict_put_str(options, "node-name", arg->node_name);
3014      }
3015      if (format) {
3016          qdict_put_str(options, "driver", format);
3017      }
3018  
3019      /* Mirroring takes care of copy-on-write using the source's backing
3020       * file.
3021       */
3022      target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
3023      if (!target_bs) {
3024          return;
3025      }
3026  
3027      bdrv_graph_rdlock_main_loop();
3028      zero_target = (arg->sync == MIRROR_SYNC_MODE_FULL &&
3029                     (arg->mode == NEW_IMAGE_MODE_EXISTING ||
3030                      !bdrv_has_zero_init(target_bs)));
3031      bdrv_graph_rdunlock_main_loop();
3032  
3033  
3034      ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3035      if (ret < 0) {
3036          bdrv_unref(target_bs);
3037          return;
3038      }
3039  
3040      blockdev_mirror_common(arg->job_id, bs, target_bs,
3041                             arg->replaces, arg->sync,
3042                             backing_mode, zero_target,
3043                             arg->has_speed, arg->speed,
3044                             arg->has_granularity, arg->granularity,
3045                             arg->has_buf_size, arg->buf_size,
3046                             arg->has_on_source_error, arg->on_source_error,
3047                             arg->has_on_target_error, arg->on_target_error,
3048                             arg->has_unmap, arg->unmap,
3049                             NULL,
3050                             arg->has_copy_mode, arg->copy_mode,
3051                             arg->has_auto_finalize, arg->auto_finalize,
3052                             arg->has_auto_dismiss, arg->auto_dismiss,
3053                             errp);
3054      bdrv_unref(target_bs);
3055  }
3056  
3057  void qmp_blockdev_mirror(const char *job_id,
3058                           const char *device, const char *target,
3059                           const char *replaces,
3060                           MirrorSyncMode sync,
3061                           bool has_speed, int64_t speed,
3062                           bool has_granularity, uint32_t granularity,
3063                           bool has_buf_size, int64_t buf_size,
3064                           bool has_on_source_error,
3065                           BlockdevOnError on_source_error,
3066                           bool has_on_target_error,
3067                           BlockdevOnError on_target_error,
3068                           const char *filter_node_name,
3069                           bool has_copy_mode, MirrorCopyMode copy_mode,
3070                           bool has_auto_finalize, bool auto_finalize,
3071                           bool has_auto_dismiss, bool auto_dismiss,
3072                           Error **errp)
3073  {
3074      BlockDriverState *bs;
3075      BlockDriverState *target_bs;
3076      AioContext *aio_context;
3077      BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
3078      bool zero_target;
3079      int ret;
3080  
3081      bs = qmp_get_root_bs(device, errp);
3082      if (!bs) {
3083          return;
3084      }
3085  
3086      target_bs = bdrv_lookup_bs(target, target, errp);
3087      if (!target_bs) {
3088          return;
3089      }
3090  
3091      zero_target = (sync == MIRROR_SYNC_MODE_FULL);
3092  
3093      aio_context = bdrv_get_aio_context(bs);
3094  
3095      ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3096      if (ret < 0) {
3097          return;
3098      }
3099  
3100      blockdev_mirror_common(job_id, bs, target_bs,
3101                             replaces, sync, backing_mode,
3102                             zero_target, has_speed, speed,
3103                             has_granularity, granularity,
3104                             has_buf_size, buf_size,
3105                             has_on_source_error, on_source_error,
3106                             has_on_target_error, on_target_error,
3107                             true, true, filter_node_name,
3108                             has_copy_mode, copy_mode,
3109                             has_auto_finalize, auto_finalize,
3110                             has_auto_dismiss, auto_dismiss,
3111                             errp);
3112  }
3113  
3114  /*
3115   * Get a block job using its ID. Called with job_mutex held.
3116   */
3117  static BlockJob *find_block_job_locked(const char *id, Error **errp)
3118  {
3119      BlockJob *job;
3120  
3121      assert(id != NULL);
3122  
3123      job = block_job_get_locked(id);
3124  
3125      if (!job) {
3126          error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
3127                    "Block job '%s' not found", id);
3128          return NULL;
3129      }
3130  
3131      return job;
3132  }
3133  
3134  void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
3135  {
3136      BlockJob *job;
3137  
3138      JOB_LOCK_GUARD();
3139      job = find_block_job_locked(device, errp);
3140  
3141      if (!job) {
3142          return;
3143      }
3144  
3145      block_job_set_speed_locked(job, speed, errp);
3146  }
3147  
3148  void qmp_block_job_cancel(const char *device,
3149                            bool has_force, bool force, Error **errp)
3150  {
3151      BlockJob *job;
3152  
3153      JOB_LOCK_GUARD();
3154      job = find_block_job_locked(device, errp);
3155  
3156      if (!job) {
3157          return;
3158      }
3159  
3160      if (!has_force) {
3161          force = false;
3162      }
3163  
3164      if (job_user_paused_locked(&job->job) && !force) {
3165          error_setg(errp, "The block job for device '%s' is currently paused",
3166                     device);
3167          return;
3168      }
3169  
3170      trace_qmp_block_job_cancel(job);
3171      job_user_cancel_locked(&job->job, force, errp);
3172  }
3173  
3174  void qmp_block_job_pause(const char *device, Error **errp)
3175  {
3176      BlockJob *job;
3177  
3178      JOB_LOCK_GUARD();
3179      job = find_block_job_locked(device, errp);
3180  
3181      if (!job) {
3182          return;
3183      }
3184  
3185      trace_qmp_block_job_pause(job);
3186      job_user_pause_locked(&job->job, errp);
3187  }
3188  
3189  void qmp_block_job_resume(const char *device, Error **errp)
3190  {
3191      BlockJob *job;
3192  
3193      JOB_LOCK_GUARD();
3194      job = find_block_job_locked(device, errp);
3195  
3196      if (!job) {
3197          return;
3198      }
3199  
3200      trace_qmp_block_job_resume(job);
3201      job_user_resume_locked(&job->job, errp);
3202  }
3203  
3204  void qmp_block_job_complete(const char *device, Error **errp)
3205  {
3206      BlockJob *job;
3207  
3208      JOB_LOCK_GUARD();
3209      job = find_block_job_locked(device, errp);
3210  
3211      if (!job) {
3212          return;
3213      }
3214  
3215      trace_qmp_block_job_complete(job);
3216      job_complete_locked(&job->job, errp);
3217  }
3218  
3219  void qmp_block_job_finalize(const char *id, Error **errp)
3220  {
3221      BlockJob *job;
3222  
3223      JOB_LOCK_GUARD();
3224      job = find_block_job_locked(id, errp);
3225  
3226      if (!job) {
3227          return;
3228      }
3229  
3230      trace_qmp_block_job_finalize(job);
3231      job_ref_locked(&job->job);
3232      job_finalize_locked(&job->job, errp);
3233  
3234      job_unref_locked(&job->job);
3235  }
3236  
3237  void qmp_block_job_dismiss(const char *id, Error **errp)
3238  {
3239      BlockJob *bjob;
3240      Job *job;
3241  
3242      JOB_LOCK_GUARD();
3243      bjob = find_block_job_locked(id, errp);
3244  
3245      if (!bjob) {
3246          return;
3247      }
3248  
3249      trace_qmp_block_job_dismiss(bjob);
3250      job = &bjob->job;
3251      job_dismiss_locked(&job, errp);
3252  }
3253  
3254  void qmp_block_job_change(BlockJobChangeOptions *opts, Error **errp)
3255  {
3256      BlockJob *job;
3257  
3258      JOB_LOCK_GUARD();
3259      job = find_block_job_locked(opts->id, errp);
3260  
3261      if (!job) {
3262          return;
3263      }
3264  
3265      block_job_change_locked(job, opts, errp);
3266  }
3267  
3268  void qmp_change_backing_file(const char *device,
3269                               const char *image_node_name,
3270                               const char *backing_file,
3271                               Error **errp)
3272  {
3273      BlockDriverState *bs = NULL;
3274      BlockDriverState *image_bs = NULL;
3275      Error *local_err = NULL;
3276      bool ro;
3277      int ret;
3278  
3279      bs = qmp_get_root_bs(device, errp);
3280      if (!bs) {
3281          return;
3282      }
3283  
3284      bdrv_graph_rdlock_main_loop();
3285  
3286      image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
3287      if (local_err) {
3288          error_propagate(errp, local_err);
3289          goto out_rdlock;
3290      }
3291  
3292      if (!image_bs) {
3293          error_setg(errp, "image file not found");
3294          goto out_rdlock;
3295      }
3296  
3297      if (bdrv_find_base(image_bs) == image_bs) {
3298          error_setg(errp, "not allowing backing file change on an image "
3299                           "without a backing file");
3300          goto out_rdlock;
3301      }
3302  
3303      /* even though we are not necessarily operating on bs, we need it to
3304       * determine if block ops are currently prohibited on the chain */
3305      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
3306          goto out_rdlock;
3307      }
3308  
3309      /* final sanity check */
3310      if (!bdrv_chain_contains(bs, image_bs)) {
3311          error_setg(errp, "'%s' and image file are not in the same chain",
3312                     device);
3313          goto out_rdlock;
3314      }
3315      bdrv_graph_rdunlock_main_loop();
3316  
3317      /* if not r/w, reopen to make r/w */
3318      ro = bdrv_is_read_only(image_bs);
3319  
3320      if (ro) {
3321          if (bdrv_reopen_set_read_only(image_bs, false, errp) != 0) {
3322              return;
3323          }
3324      }
3325  
3326      ret = bdrv_change_backing_file(image_bs, backing_file,
3327                                     image_bs->drv ? image_bs->drv->format_name : "",
3328                                     false);
3329  
3330      if (ret < 0) {
3331          error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
3332                           backing_file);
3333          /* don't exit here, so we can try to restore open flags if
3334           * appropriate */
3335      }
3336  
3337      if (ro) {
3338          bdrv_reopen_set_read_only(image_bs, true, errp);
3339      }
3340      return;
3341  
3342  out_rdlock:
3343      bdrv_graph_rdunlock_main_loop();
3344  }
3345  
3346  void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
3347  {
3348      BlockDriverState *bs;
3349      QObject *obj;
3350      Visitor *v = qobject_output_visitor_new(&obj);
3351      QDict *qdict;
3352  
3353      visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3354      visit_complete(v, &obj);
3355      qdict = qobject_to(QDict, obj);
3356  
3357      qdict_flatten(qdict);
3358  
3359      if (!qdict_get_try_str(qdict, "node-name")) {
3360          error_setg(errp, "'node-name' must be specified for the root node");
3361          goto fail;
3362      }
3363  
3364      bs = bds_tree_init(qdict, errp);
3365      if (!bs) {
3366          goto fail;
3367      }
3368  
3369      bdrv_set_monitor_owned(bs);
3370  
3371  fail:
3372      visit_free(v);
3373  }
3374  
3375  void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
3376  {
3377      BlockReopenQueue *queue = NULL;
3378  
3379      /* Add each one of the BDS that we want to reopen to the queue */
3380      for (; reopen_list != NULL; reopen_list = reopen_list->next) {
3381          BlockdevOptions *options = reopen_list->value;
3382          BlockDriverState *bs;
3383          QObject *obj;
3384          Visitor *v;
3385          QDict *qdict;
3386  
3387          /* Check for the selected node name */
3388          if (!options->node_name) {
3389              error_setg(errp, "node-name not specified");
3390              goto fail;
3391          }
3392  
3393          bs = bdrv_find_node(options->node_name);
3394          if (!bs) {
3395              error_setg(errp, "Failed to find node with node-name='%s'",
3396                         options->node_name);
3397              goto fail;
3398          }
3399  
3400          /* Put all options in a QDict and flatten it */
3401          v = qobject_output_visitor_new(&obj);
3402          visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3403          visit_complete(v, &obj);
3404          visit_free(v);
3405  
3406          qdict = qobject_to(QDict, obj);
3407  
3408          qdict_flatten(qdict);
3409  
3410          queue = bdrv_reopen_queue(queue, bs, qdict, false);
3411      }
3412  
3413      /* Perform the reopen operation */
3414      bdrv_reopen_multiple(queue, errp);
3415      queue = NULL;
3416  
3417  fail:
3418      bdrv_reopen_queue_free(queue);
3419  }
3420  
3421  void qmp_blockdev_del(const char *node_name, Error **errp)
3422  {
3423      BlockDriverState *bs;
3424  
3425      GLOBAL_STATE_CODE();
3426      GRAPH_RDLOCK_GUARD_MAINLOOP();
3427  
3428      bs = bdrv_find_node(node_name);
3429      if (!bs) {
3430          error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3431          return;
3432      }
3433      if (bdrv_has_blk(bs)) {
3434          error_setg(errp, "Node %s is in use", node_name);
3435          return;
3436      }
3437  
3438      if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
3439          return;
3440      }
3441  
3442      if (!QTAILQ_IN_USE(bs, monitor_list)) {
3443          error_setg(errp, "Node %s is not owned by the monitor",
3444                     bs->node_name);
3445          return;
3446      }
3447  
3448      if (bs->refcnt > 1) {
3449          error_setg(errp, "Block device %s is in use",
3450                     bdrv_get_device_or_node_name(bs));
3451          return;
3452      }
3453  
3454      QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
3455      bdrv_unref(bs);
3456  }
3457  
3458  static BdrvChild * GRAPH_RDLOCK
3459  bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
3460  {
3461      BdrvChild *child;
3462  
3463      QLIST_FOREACH(child, &parent_bs->children, next) {
3464          if (strcmp(child->name, child_name) == 0) {
3465              return child;
3466          }
3467      }
3468  
3469      return NULL;
3470  }
3471  
3472  void qmp_x_blockdev_change(const char *parent, const char *child,
3473                             const char *node, Error **errp)
3474  {
3475      BlockDriverState *parent_bs, *new_bs = NULL;
3476      BdrvChild *p_child;
3477  
3478      bdrv_graph_wrlock();
3479  
3480      parent_bs = bdrv_lookup_bs(parent, parent, errp);
3481      if (!parent_bs) {
3482          goto out;
3483      }
3484  
3485      if (!child == !node) {
3486          if (child) {
3487              error_setg(errp, "The parameters child and node are in conflict");
3488          } else {
3489              error_setg(errp, "Either child or node must be specified");
3490          }
3491          goto out;
3492      }
3493  
3494      if (child) {
3495          p_child = bdrv_find_child(parent_bs, child);
3496          if (!p_child) {
3497              error_setg(errp, "Node '%s' does not have child '%s'",
3498                         parent, child);
3499              goto out;
3500          }
3501          bdrv_del_child(parent_bs, p_child, errp);
3502      }
3503  
3504      if (node) {
3505          new_bs = bdrv_find_node(node);
3506          if (!new_bs) {
3507              error_setg(errp, "Node '%s' not found", node);
3508              goto out;
3509          }
3510          bdrv_add_child(parent_bs, new_bs, errp);
3511      }
3512  
3513  out:
3514      bdrv_graph_wrunlock();
3515  }
3516  
3517  BlockJobInfoList *qmp_query_block_jobs(Error **errp)
3518  {
3519      BlockJobInfoList *head = NULL, **tail = &head;
3520      BlockJob *job;
3521  
3522      JOB_LOCK_GUARD();
3523  
3524      for (job = block_job_next_locked(NULL); job;
3525           job = block_job_next_locked(job)) {
3526          BlockJobInfo *value;
3527  
3528          if (block_job_is_internal(job)) {
3529              continue;
3530          }
3531          value = block_job_query_locked(job, errp);
3532          if (!value) {
3533              qapi_free_BlockJobInfoList(head);
3534              return NULL;
3535          }
3536          QAPI_LIST_APPEND(tail, value);
3537      }
3538  
3539      return head;
3540  }
3541  
3542  void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
3543                                   bool has_force, bool force, Error **errp)
3544  {
3545      AioContext *new_context;
3546      BlockDriverState *bs;
3547  
3548      GRAPH_RDLOCK_GUARD_MAINLOOP();
3549  
3550      bs = bdrv_find_node(node_name);
3551      if (!bs) {
3552          error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3553          return;
3554      }
3555  
3556      /* Protects against accidents. */
3557      if (!(has_force && force) && bdrv_has_blk(bs)) {
3558          error_setg(errp, "Node %s is associated with a BlockBackend and could "
3559                           "be in use (use force=true to override this check)",
3560                           node_name);
3561          return;
3562      }
3563  
3564      if (iothread->type == QTYPE_QSTRING) {
3565          IOThread *obj = iothread_by_id(iothread->u.s);
3566          if (!obj) {
3567              error_setg(errp, "Cannot find iothread %s", iothread->u.s);
3568              return;
3569          }
3570  
3571          new_context = iothread_get_aio_context(obj);
3572      } else {
3573          new_context = qemu_get_aio_context();
3574      }
3575  
3576      bdrv_try_change_aio_context(bs, new_context, NULL, errp);
3577  }
3578  
3579  QemuOptsList qemu_common_drive_opts = {
3580      .name = "drive",
3581      .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
3582      .desc = {
3583          {
3584              .name = "snapshot",
3585              .type = QEMU_OPT_BOOL,
3586              .help = "enable/disable snapshot mode",
3587          },{
3588              .name = "aio",
3589              .type = QEMU_OPT_STRING,
3590              .help = "host AIO implementation (threads, native, io_uring)",
3591          },{
3592              .name = BDRV_OPT_CACHE_WB,
3593              .type = QEMU_OPT_BOOL,
3594              .help = "Enable writeback mode",
3595          },{
3596              .name = "format",
3597              .type = QEMU_OPT_STRING,
3598              .help = "disk format (raw, qcow2, ...)",
3599          },{
3600              .name = "rerror",
3601              .type = QEMU_OPT_STRING,
3602              .help = "read error action",
3603          },{
3604              .name = "werror",
3605              .type = QEMU_OPT_STRING,
3606              .help = "write error action",
3607          },{
3608              .name = BDRV_OPT_READ_ONLY,
3609              .type = QEMU_OPT_BOOL,
3610              .help = "open drive file as read-only",
3611          },
3612  
3613          THROTTLE_OPTS,
3614  
3615          {
3616              .name = "throttling.group",
3617              .type = QEMU_OPT_STRING,
3618              .help = "name of the block throttling group",
3619          },{
3620              .name = "copy-on-read",
3621              .type = QEMU_OPT_BOOL,
3622              .help = "copy read data from backing file into image file",
3623          },{
3624              .name = "detect-zeroes",
3625              .type = QEMU_OPT_STRING,
3626              .help = "try to optimize zero writes (off, on, unmap)",
3627          },{
3628              .name = "stats-account-invalid",
3629              .type = QEMU_OPT_BOOL,
3630              .help = "whether to account for invalid I/O operations "
3631                      "in the statistics",
3632          },{
3633              .name = "stats-account-failed",
3634              .type = QEMU_OPT_BOOL,
3635              .help = "whether to account for failed I/O operations "
3636                      "in the statistics",
3637          },
3638          { /* end of list */ }
3639      },
3640  };
3641  
3642  QemuOptsList qemu_drive_opts = {
3643      .name = "drive",
3644      .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
3645      .desc = {
3646          /*
3647           * no elements => accept any params
3648           * validation will happen later
3649           */
3650          { /* end of list */ }
3651      },
3652  };
3653