xref: /openbmc/qemu/blockdev.c (revision 2abf0da2)
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, QERR_DEVICE_HAS_NO_MEDIUM, device);
1399         return;
1400     }
1401 
1402     if (bdrv_op_is_blocked(state->old_bs,
1403                            BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
1404         return;
1405     }
1406 
1407     if (!bdrv_is_read_only(state->old_bs)) {
1408         if (bdrv_flush(state->old_bs)) {
1409             error_setg(errp, QERR_IO_ERROR);
1410             return;
1411         }
1412     }
1413 
1414     if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
1415         BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1416         const char *format = s->format ?: "qcow2";
1417         enum NewImageMode mode;
1418         const char *snapshot_node_name = s->snapshot_node_name;
1419 
1420         if (node_name && !snapshot_node_name) {
1421             error_setg(errp, "New overlay node-name missing");
1422             return;
1423         }
1424 
1425         if (snapshot_node_name &&
1426             bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
1427             error_setg(errp, "New overlay node-name already in use");
1428             return;
1429         }
1430 
1431         flags = state->old_bs->open_flags;
1432         flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ);
1433         flags |= BDRV_O_NO_BACKING;
1434 
1435         /* create new image w/backing file */
1436         mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1437         if (mode != NEW_IMAGE_MODE_EXISTING) {
1438             int64_t size = bdrv_getlength(state->old_bs);
1439             if (size < 0) {
1440                 error_setg_errno(errp, -size, "bdrv_getlength failed");
1441                 return;
1442             }
1443             bdrv_refresh_filename(state->old_bs);
1444 
1445             bdrv_img_create(new_image_file, format,
1446                             state->old_bs->filename,
1447                             state->old_bs->drv->format_name,
1448                             NULL, size, flags, false, &local_err);
1449 
1450             if (local_err) {
1451                 error_propagate(errp, local_err);
1452                 return;
1453             }
1454         }
1455 
1456         options = qdict_new();
1457         if (snapshot_node_name) {
1458             qdict_put_str(options, "node-name", snapshot_node_name);
1459         }
1460         qdict_put_str(options, "driver", format);
1461     }
1462 
1463     state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
1464                               errp);
1465 
1466     /* We will manually add the backing_hd field to the bs later */
1467     if (!state->new_bs) {
1468         return;
1469     }
1470 
1471     /*
1472      * Allow attaching a backing file to an overlay that's already in use only
1473      * if the parents don't assume that they are already seeing a valid image.
1474      * (Specifically, allow it as a mirror target, which is write-only access.)
1475      */
1476     bdrv_get_cumulative_perm(state->new_bs, &perm, &shared);
1477     if (perm & BLK_PERM_CONSISTENT_READ) {
1478         error_setg(errp, "The overlay is already in use");
1479         return;
1480     }
1481 
1482     if (state->new_bs->drv->is_filter) {
1483         error_setg(errp, "Filters cannot be used as overlays");
1484         return;
1485     }
1486 
1487     if (bdrv_cow_child(state->new_bs)) {
1488         error_setg(errp, "The overlay already has a backing image");
1489         return;
1490     }
1491 
1492     if (!state->new_bs->drv->supports_backing) {
1493         error_setg(errp, "The overlay does not support backing images");
1494         return;
1495     }
1496 
1497     ret = bdrv_append(state->new_bs, state->old_bs, errp);
1498     if (ret < 0) {
1499         return;
1500     }
1501     state->overlay_appended = true;
1502 }
1503 
1504 static void external_snapshot_commit(void *opaque)
1505 {
1506     ExternalSnapshotState *state = opaque;
1507 
1508     /* We don't need (or want) to use the transactional
1509      * bdrv_reopen_multiple() across all the entries at once, because we
1510      * don't want to abort all of them if one of them fails the reopen */
1511     if (!qatomic_read(&state->old_bs->copy_on_read)) {
1512         bdrv_reopen_set_read_only(state->old_bs, true, NULL);
1513     }
1514 }
1515 
1516 static void external_snapshot_abort(void *opaque)
1517 {
1518     ExternalSnapshotState *state = opaque;
1519     if (state->new_bs) {
1520         if (state->overlay_appended) {
1521             AioContext *aio_context;
1522             AioContext *tmp_context;
1523             int ret;
1524 
1525             aio_context = bdrv_get_aio_context(state->old_bs);
1526 
1527             bdrv_ref(state->old_bs);   /* we can't let bdrv_set_backind_hd()
1528                                           close state->old_bs; we need it */
1529             bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
1530 
1531             /*
1532              * The call to bdrv_set_backing_hd() above returns state->old_bs to
1533              * the main AioContext. As we're still going to be using it, return
1534              * it to the AioContext it was before.
1535              */
1536             tmp_context = bdrv_get_aio_context(state->old_bs);
1537             if (aio_context != tmp_context) {
1538                 ret = bdrv_try_change_aio_context(state->old_bs,
1539                                                   aio_context, NULL, NULL);
1540                 assert(ret == 0);
1541             }
1542 
1543             bdrv_drained_begin(state->new_bs);
1544             bdrv_graph_wrlock();
1545             bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
1546             bdrv_graph_wrunlock();
1547             bdrv_drained_end(state->new_bs);
1548 
1549             bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
1550         }
1551     }
1552 }
1553 
1554 static void external_snapshot_clean(void *opaque)
1555 {
1556     g_autofree ExternalSnapshotState *state = opaque;
1557 
1558     if (!state->old_bs) {
1559         return;
1560     }
1561 
1562     bdrv_drained_end(state->old_bs);
1563     bdrv_unref(state->new_bs);
1564 }
1565 
1566 typedef struct DriveBackupState {
1567     BlockDriverState *bs;
1568     BlockJob *job;
1569 } DriveBackupState;
1570 
1571 static BlockJob *do_backup_common(BackupCommon *backup,
1572                                   BlockDriverState *bs,
1573                                   BlockDriverState *target_bs,
1574                                   AioContext *aio_context,
1575                                   JobTxn *txn, Error **errp);
1576 
1577 static void drive_backup_commit(void *opaque);
1578 static void drive_backup_abort(void *opaque);
1579 static void drive_backup_clean(void *opaque);
1580 TransactionActionDrv drive_backup_drv = {
1581     .commit = drive_backup_commit,
1582     .abort = drive_backup_abort,
1583     .clean = drive_backup_clean,
1584 };
1585 
1586 static void drive_backup_action(DriveBackup *backup,
1587                                 JobTxn *block_job_txn,
1588                                 Transaction *tran, Error **errp)
1589 {
1590     DriveBackupState *state = g_new0(DriveBackupState, 1);
1591     BlockDriverState *bs;
1592     BlockDriverState *target_bs;
1593     BlockDriverState *source = NULL;
1594     AioContext *aio_context;
1595     const char *format;
1596     QDict *options;
1597     Error *local_err = NULL;
1598     int flags;
1599     int64_t size;
1600     bool set_backing_hd = false;
1601     int ret;
1602 
1603     GLOBAL_STATE_CODE();
1604 
1605     tran_add(tran, &drive_backup_drv, state);
1606 
1607     if (!backup->has_mode) {
1608         backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1609     }
1610 
1611     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1612     if (!bs) {
1613         return;
1614     }
1615 
1616     if (!bs->drv) {
1617         error_setg(errp, "Device has no medium");
1618         return;
1619     }
1620 
1621     aio_context = bdrv_get_aio_context(bs);
1622 
1623     state->bs = bs;
1624     /* Paired with .clean() */
1625     bdrv_drained_begin(bs);
1626 
1627     format = backup->format;
1628     if (!format && backup->mode != NEW_IMAGE_MODE_EXISTING) {
1629         format = bs->drv->format_name;
1630     }
1631 
1632     /* Early check to avoid creating target */
1633     bdrv_graph_rdlock_main_loop();
1634     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
1635         bdrv_graph_rdunlock_main_loop();
1636         return;
1637     }
1638 
1639     flags = bs->open_flags | BDRV_O_RDWR;
1640 
1641     /*
1642      * See if we have a backing HD we can use to create our new image
1643      * on top of.
1644      */
1645     if (backup->sync == MIRROR_SYNC_MODE_TOP) {
1646         /*
1647          * Backup will not replace the source by the target, so none
1648          * of the filters skipped here will be removed (in contrast to
1649          * mirror).  Therefore, we can skip all of them when looking
1650          * for the first COW relationship.
1651          */
1652         source = bdrv_cow_bs(bdrv_skip_filters(bs));
1653         if (!source) {
1654             backup->sync = MIRROR_SYNC_MODE_FULL;
1655         }
1656     }
1657     if (backup->sync == MIRROR_SYNC_MODE_NONE) {
1658         source = bs;
1659         flags |= BDRV_O_NO_BACKING;
1660         set_backing_hd = true;
1661     }
1662     bdrv_graph_rdunlock_main_loop();
1663 
1664     size = bdrv_getlength(bs);
1665     if (size < 0) {
1666         error_setg_errno(errp, -size, "bdrv_getlength failed");
1667         return;
1668     }
1669 
1670     if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
1671         assert(format);
1672         if (source) {
1673             /* Implicit filters should not appear in the filename */
1674             BlockDriverState *explicit_backing;
1675 
1676             bdrv_graph_rdlock_main_loop();
1677             explicit_backing = bdrv_skip_implicit_filters(source);
1678             bdrv_refresh_filename(explicit_backing);
1679             bdrv_graph_rdunlock_main_loop();
1680 
1681             bdrv_img_create(backup->target, format,
1682                             explicit_backing->filename,
1683                             explicit_backing->drv->format_name, NULL,
1684                             size, flags, false, &local_err);
1685         } else {
1686             bdrv_img_create(backup->target, format, NULL, NULL, NULL,
1687                             size, flags, false, &local_err);
1688         }
1689     }
1690 
1691     if (local_err) {
1692         error_propagate(errp, local_err);
1693         return;
1694     }
1695 
1696     options = qdict_new();
1697     qdict_put_str(options, "discard", "unmap");
1698     qdict_put_str(options, "detect-zeroes", "unmap");
1699     if (format) {
1700         qdict_put_str(options, "driver", format);
1701     }
1702 
1703     target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
1704     if (!target_bs) {
1705         return;
1706     }
1707 
1708     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1709     if (ret < 0) {
1710         bdrv_unref(target_bs);
1711         return;
1712     }
1713 
1714     if (set_backing_hd) {
1715         if (bdrv_set_backing_hd(target_bs, source, errp) < 0) {
1716             goto unref;
1717         }
1718     }
1719 
1720     state->job = do_backup_common(qapi_DriveBackup_base(backup),
1721                                   bs, target_bs, aio_context,
1722                                   block_job_txn, errp);
1723 
1724 unref:
1725     bdrv_unref(target_bs);
1726 }
1727 
1728 static void drive_backup_commit(void *opaque)
1729 {
1730     DriveBackupState *state = opaque;
1731 
1732     assert(state->job);
1733     job_start(&state->job->job);
1734 }
1735 
1736 static void drive_backup_abort(void *opaque)
1737 {
1738     DriveBackupState *state = opaque;
1739 
1740     if (state->job) {
1741         job_cancel_sync(&state->job->job, true);
1742     }
1743 }
1744 
1745 static void drive_backup_clean(void *opaque)
1746 {
1747     g_autofree DriveBackupState *state = opaque;
1748 
1749     if (!state->bs) {
1750         return;
1751     }
1752 
1753     bdrv_drained_end(state->bs);
1754 }
1755 
1756 typedef struct BlockdevBackupState {
1757     BlockDriverState *bs;
1758     BlockJob *job;
1759 } BlockdevBackupState;
1760 
1761 static void blockdev_backup_commit(void *opaque);
1762 static void blockdev_backup_abort(void *opaque);
1763 static void blockdev_backup_clean(void *opaque);
1764 TransactionActionDrv blockdev_backup_drv = {
1765     .commit = blockdev_backup_commit,
1766     .abort = blockdev_backup_abort,
1767     .clean = blockdev_backup_clean,
1768 };
1769 
1770 static void blockdev_backup_action(BlockdevBackup *backup,
1771                                    JobTxn *block_job_txn,
1772                                    Transaction *tran, Error **errp)
1773 {
1774     BlockdevBackupState *state = g_new0(BlockdevBackupState, 1);
1775     BlockDriverState *bs;
1776     BlockDriverState *target_bs;
1777     AioContext *aio_context;
1778     int ret;
1779 
1780     tran_add(tran, &blockdev_backup_drv, state);
1781 
1782     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1783     if (!bs) {
1784         return;
1785     }
1786 
1787     target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
1788     if (!target_bs) {
1789         return;
1790     }
1791 
1792     /* Honor bdrv_try_change_aio_context() context acquisition requirements. */
1793     aio_context = bdrv_get_aio_context(bs);
1794 
1795     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1796     if (ret < 0) {
1797         return;
1798     }
1799 
1800     state->bs = bs;
1801 
1802     /* Paired with .clean() */
1803     bdrv_drained_begin(state->bs);
1804 
1805     state->job = do_backup_common(qapi_BlockdevBackup_base(backup),
1806                                   bs, target_bs, aio_context,
1807                                   block_job_txn, errp);
1808 }
1809 
1810 static void blockdev_backup_commit(void *opaque)
1811 {
1812     BlockdevBackupState *state = opaque;
1813 
1814     assert(state->job);
1815     job_start(&state->job->job);
1816 }
1817 
1818 static void blockdev_backup_abort(void *opaque)
1819 {
1820     BlockdevBackupState *state = opaque;
1821 
1822     if (state->job) {
1823         job_cancel_sync(&state->job->job, true);
1824     }
1825 }
1826 
1827 static void blockdev_backup_clean(void *opaque)
1828 {
1829     g_autofree BlockdevBackupState *state = opaque;
1830 
1831     if (!state->bs) {
1832         return;
1833     }
1834 
1835     bdrv_drained_end(state->bs);
1836 }
1837 
1838 typedef struct BlockDirtyBitmapState {
1839     BdrvDirtyBitmap *bitmap;
1840     BlockDriverState *bs;
1841     HBitmap *backup;
1842     bool was_enabled;
1843 } BlockDirtyBitmapState;
1844 
1845 static void block_dirty_bitmap_add_abort(void *opaque);
1846 TransactionActionDrv block_dirty_bitmap_add_drv = {
1847     .abort = block_dirty_bitmap_add_abort,
1848     .clean = g_free,
1849 };
1850 
1851 static void block_dirty_bitmap_add_action(BlockDirtyBitmapAdd *action,
1852                                           Transaction *tran, Error **errp)
1853 {
1854     Error *local_err = NULL;
1855     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1856 
1857     tran_add(tran, &block_dirty_bitmap_add_drv, state);
1858 
1859     /* AIO context taken and released within qmp_block_dirty_bitmap_add */
1860     qmp_block_dirty_bitmap_add(action->node, action->name,
1861                                action->has_granularity, action->granularity,
1862                                action->has_persistent, action->persistent,
1863                                action->has_disabled, action->disabled,
1864                                &local_err);
1865 
1866     if (!local_err) {
1867         state->bitmap = block_dirty_bitmap_lookup(action->node, action->name,
1868                                                   NULL, &error_abort);
1869     } else {
1870         error_propagate(errp, local_err);
1871     }
1872 }
1873 
1874 static void block_dirty_bitmap_add_abort(void *opaque)
1875 {
1876     BlockDirtyBitmapState *state = opaque;
1877 
1878     if (state->bitmap) {
1879         bdrv_release_dirty_bitmap(state->bitmap);
1880     }
1881 }
1882 
1883 static void block_dirty_bitmap_restore(void *opaque);
1884 static void block_dirty_bitmap_free_backup(void *opaque);
1885 TransactionActionDrv block_dirty_bitmap_clear_drv = {
1886     .abort = block_dirty_bitmap_restore,
1887     .commit = block_dirty_bitmap_free_backup,
1888     .clean = g_free,
1889 };
1890 
1891 static void block_dirty_bitmap_clear_action(BlockDirtyBitmap *action,
1892                                             Transaction *tran, Error **errp)
1893 {
1894     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1895 
1896     tran_add(tran, &block_dirty_bitmap_clear_drv, state);
1897 
1898     state->bitmap = block_dirty_bitmap_lookup(action->node,
1899                                               action->name,
1900                                               &state->bs,
1901                                               errp);
1902     if (!state->bitmap) {
1903         return;
1904     }
1905 
1906     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_DEFAULT, errp)) {
1907         return;
1908     }
1909 
1910     bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
1911 }
1912 
1913 static void block_dirty_bitmap_restore(void *opaque)
1914 {
1915     BlockDirtyBitmapState *state = opaque;
1916 
1917     if (state->backup) {
1918         bdrv_restore_dirty_bitmap(state->bitmap, state->backup);
1919     }
1920 }
1921 
1922 static void block_dirty_bitmap_free_backup(void *opaque)
1923 {
1924     BlockDirtyBitmapState *state = opaque;
1925 
1926     hbitmap_free(state->backup);
1927 }
1928 
1929 static void block_dirty_bitmap_enable_abort(void *opaque);
1930 TransactionActionDrv block_dirty_bitmap_enable_drv = {
1931     .abort = block_dirty_bitmap_enable_abort,
1932     .clean = g_free,
1933 };
1934 
1935 static void block_dirty_bitmap_enable_action(BlockDirtyBitmap *action,
1936                                              Transaction *tran, Error **errp)
1937 {
1938     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1939 
1940     tran_add(tran, &block_dirty_bitmap_enable_drv, state);
1941 
1942     state->bitmap = block_dirty_bitmap_lookup(action->node,
1943                                               action->name,
1944                                               NULL,
1945                                               errp);
1946     if (!state->bitmap) {
1947         return;
1948     }
1949 
1950     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
1951         return;
1952     }
1953 
1954     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
1955     bdrv_enable_dirty_bitmap(state->bitmap);
1956 }
1957 
1958 static void block_dirty_bitmap_enable_abort(void *opaque)
1959 {
1960     BlockDirtyBitmapState *state = opaque;
1961 
1962     if (!state->was_enabled) {
1963         bdrv_disable_dirty_bitmap(state->bitmap);
1964     }
1965 }
1966 
1967 static void block_dirty_bitmap_disable_abort(void *opaque);
1968 TransactionActionDrv block_dirty_bitmap_disable_drv = {
1969     .abort = block_dirty_bitmap_disable_abort,
1970     .clean = g_free,
1971 };
1972 
1973 static void block_dirty_bitmap_disable_action(BlockDirtyBitmap *action,
1974                                               Transaction *tran, Error **errp)
1975 {
1976     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1977 
1978     tran_add(tran, &block_dirty_bitmap_disable_drv, state);
1979 
1980     state->bitmap = block_dirty_bitmap_lookup(action->node,
1981                                               action->name,
1982                                               NULL,
1983                                               errp);
1984     if (!state->bitmap) {
1985         return;
1986     }
1987 
1988     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
1989         return;
1990     }
1991 
1992     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
1993     bdrv_disable_dirty_bitmap(state->bitmap);
1994 }
1995 
1996 static void block_dirty_bitmap_disable_abort(void *opaque)
1997 {
1998     BlockDirtyBitmapState *state = opaque;
1999 
2000     if (state->was_enabled) {
2001         bdrv_enable_dirty_bitmap(state->bitmap);
2002     }
2003 }
2004 
2005 TransactionActionDrv block_dirty_bitmap_merge_drv = {
2006     .commit = block_dirty_bitmap_free_backup,
2007     .abort = block_dirty_bitmap_restore,
2008     .clean = g_free,
2009 };
2010 
2011 static void block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge *action,
2012                                             Transaction *tran, Error **errp)
2013 {
2014     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2015 
2016     tran_add(tran, &block_dirty_bitmap_merge_drv, state);
2017 
2018     state->bitmap = block_dirty_bitmap_merge(action->node, action->target,
2019                                              action->bitmaps, &state->backup,
2020                                              errp);
2021 }
2022 
2023 static void block_dirty_bitmap_remove_commit(void *opaque);
2024 static void block_dirty_bitmap_remove_abort(void *opaque);
2025 TransactionActionDrv block_dirty_bitmap_remove_drv = {
2026     .commit = block_dirty_bitmap_remove_commit,
2027     .abort = block_dirty_bitmap_remove_abort,
2028     .clean = g_free,
2029 };
2030 
2031 static void block_dirty_bitmap_remove_action(BlockDirtyBitmap *action,
2032                                              Transaction *tran, Error **errp)
2033 {
2034     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2035 
2036     tran_add(tran, &block_dirty_bitmap_remove_drv, state);
2037 
2038 
2039     state->bitmap = block_dirty_bitmap_remove(action->node, action->name,
2040                                               false, &state->bs, errp);
2041     if (state->bitmap) {
2042         bdrv_dirty_bitmap_skip_store(state->bitmap, true);
2043         bdrv_dirty_bitmap_set_busy(state->bitmap, true);
2044     }
2045 }
2046 
2047 static void block_dirty_bitmap_remove_abort(void *opaque)
2048 {
2049     BlockDirtyBitmapState *state = opaque;
2050 
2051     if (state->bitmap) {
2052         bdrv_dirty_bitmap_skip_store(state->bitmap, false);
2053         bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2054     }
2055 }
2056 
2057 static void block_dirty_bitmap_remove_commit(void *opaque)
2058 {
2059     BlockDirtyBitmapState *state = opaque;
2060 
2061     bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2062     bdrv_release_dirty_bitmap(state->bitmap);
2063 }
2064 
2065 static void abort_commit(void *opaque);
2066 TransactionActionDrv abort_drv = {
2067     .commit = abort_commit,
2068 };
2069 
2070 static void abort_action(Transaction *tran, Error **errp)
2071 {
2072     tran_add(tran, &abort_drv, NULL);
2073     error_setg(errp, "Transaction aborted using Abort action");
2074 }
2075 
2076 static void abort_commit(void *opaque)
2077 {
2078     g_assert_not_reached(); /* this action never succeeds */
2079 }
2080 
2081 static void transaction_action(TransactionAction *act, JobTxn *block_job_txn,
2082                                Transaction *tran, Error **errp)
2083 {
2084     switch (act->type) {
2085     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
2086     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
2087         external_snapshot_action(act, tran, errp);
2088         return;
2089     case TRANSACTION_ACTION_KIND_DRIVE_BACKUP:
2090         drive_backup_action(act->u.drive_backup.data,
2091                             block_job_txn, tran, errp);
2092         return;
2093     case TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP:
2094         blockdev_backup_action(act->u.blockdev_backup.data,
2095                                block_job_txn, tran, errp);
2096         return;
2097     case TRANSACTION_ACTION_KIND_ABORT:
2098         abort_action(tran, errp);
2099         return;
2100     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC:
2101         internal_snapshot_action(act->u.blockdev_snapshot_internal_sync.data,
2102                                  tran, errp);
2103         return;
2104     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD:
2105         block_dirty_bitmap_add_action(act->u.block_dirty_bitmap_add.data,
2106                                       tran, errp);
2107         return;
2108     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR:
2109         block_dirty_bitmap_clear_action(act->u.block_dirty_bitmap_clear.data,
2110                                         tran, errp);
2111         return;
2112     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ENABLE:
2113         block_dirty_bitmap_enable_action(act->u.block_dirty_bitmap_enable.data,
2114                                          tran, errp);
2115         return;
2116     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_DISABLE:
2117         block_dirty_bitmap_disable_action(
2118                 act->u.block_dirty_bitmap_disable.data, tran, errp);
2119         return;
2120     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_MERGE:
2121         block_dirty_bitmap_merge_action(act->u.block_dirty_bitmap_merge.data,
2122                                         tran, errp);
2123         return;
2124     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_REMOVE:
2125         block_dirty_bitmap_remove_action(act->u.block_dirty_bitmap_remove.data,
2126                                          tran, errp);
2127         return;
2128     /*
2129      * Where are transactions for MIRROR, COMMIT and STREAM?
2130      * Although these blockjobs use transaction callbacks like the backup job,
2131      * these jobs do not necessarily adhere to transaction semantics.
2132      * These jobs may not fully undo all of their actions on abort, nor do they
2133      * necessarily work in transactions with more than one job in them.
2134      */
2135     case TRANSACTION_ACTION_KIND__MAX:
2136     default:
2137         g_assert_not_reached();
2138     };
2139 }
2140 
2141 
2142 /*
2143  * 'Atomic' group operations.  The operations are performed as a set, and if
2144  * any fail then we roll back all operations in the group.
2145  *
2146  * Always run under BQL.
2147  */
2148 void qmp_transaction(TransactionActionList *actions,
2149                      struct TransactionProperties *properties,
2150                      Error **errp)
2151 {
2152     TransactionActionList *act;
2153     JobTxn *block_job_txn = NULL;
2154     Error *local_err = NULL;
2155     Transaction *tran;
2156     ActionCompletionMode comp_mode =
2157         properties ? properties->completion_mode :
2158         ACTION_COMPLETION_MODE_INDIVIDUAL;
2159 
2160     GLOBAL_STATE_CODE();
2161 
2162     /* Does this transaction get canceled as a group on failure?
2163      * If not, we don't really need to make a JobTxn.
2164      */
2165     if (comp_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
2166         for (act = actions; act; act = act->next) {
2167             TransactionActionKind type = act->value->type;
2168 
2169             if (type != TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP &&
2170                 type != TRANSACTION_ACTION_KIND_DRIVE_BACKUP)
2171             {
2172                 error_setg(errp,
2173                            "Action '%s' does not support transaction property "
2174                            "completion-mode = %s",
2175                            TransactionActionKind_str(type),
2176                            ActionCompletionMode_str(comp_mode));
2177                 return;
2178             }
2179         }
2180 
2181         block_job_txn = job_txn_new();
2182     }
2183 
2184     /* drain all i/o before any operations */
2185     bdrv_drain_all();
2186 
2187     tran = tran_new();
2188 
2189     /* We don't do anything in this loop that commits us to the operations */
2190     for (act = actions; act; act = act->next) {
2191         transaction_action(act->value, block_job_txn, tran, &local_err);
2192         if (local_err) {
2193             error_propagate(errp, local_err);
2194             goto delete_and_fail;
2195         }
2196     }
2197 
2198     tran_commit(tran);
2199 
2200     /* success */
2201     goto exit;
2202 
2203 delete_and_fail:
2204     /* failure, and it is all-or-none; roll back all operations */
2205     tran_abort(tran);
2206 exit:
2207     job_txn_unref(block_job_txn);
2208 }
2209 
2210 BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
2211                                                               const char *name,
2212                                                               Error **errp)
2213 {
2214     BdrvDirtyBitmap *bitmap;
2215     BlockDriverState *bs;
2216     BlockDirtyBitmapSha256 *ret = NULL;
2217     char *sha256;
2218 
2219     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2220     if (!bitmap || !bs) {
2221         return NULL;
2222     }
2223 
2224     sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
2225     if (sha256 == NULL) {
2226         return NULL;
2227     }
2228 
2229     ret = g_new(BlockDirtyBitmapSha256, 1);
2230     ret->sha256 = sha256;
2231 
2232     return ret;
2233 }
2234 
2235 void coroutine_fn qmp_block_resize(const char *device, const char *node_name,
2236                                    int64_t size, Error **errp)
2237 {
2238     Error *local_err = NULL;
2239     BlockBackend *blk;
2240     BlockDriverState *bs;
2241     AioContext *old_ctx;
2242 
2243     bs = bdrv_lookup_bs(device, node_name, &local_err);
2244     if (local_err) {
2245         error_propagate(errp, local_err);
2246         return;
2247     }
2248 
2249     if (size < 0) {
2250         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
2251         return;
2252     }
2253 
2254     bdrv_graph_co_rdlock();
2255     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
2256         error_setg(errp, QERR_DEVICE_IN_USE, device);
2257         bdrv_graph_co_rdunlock();
2258         return;
2259     }
2260     bdrv_graph_co_rdunlock();
2261 
2262     blk = blk_co_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
2263     if (!blk) {
2264         return;
2265     }
2266 
2267     bdrv_drained_begin(bs);
2268 
2269     old_ctx = bdrv_co_enter(bs);
2270     blk_co_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
2271     bdrv_co_leave(bs, old_ctx);
2272 
2273     bdrv_drained_end(bs);
2274     blk_co_unref(blk);
2275 }
2276 
2277 void qmp_block_stream(const char *job_id, const char *device,
2278                       const char *base,
2279                       const char *base_node,
2280                       const char *backing_file,
2281                       const char *bottom,
2282                       bool has_speed, int64_t speed,
2283                       bool has_on_error, BlockdevOnError on_error,
2284                       const char *filter_node_name,
2285                       bool has_auto_finalize, bool auto_finalize,
2286                       bool has_auto_dismiss, bool auto_dismiss,
2287                       Error **errp)
2288 {
2289     BlockDriverState *bs, *iter, *iter_end;
2290     BlockDriverState *base_bs = NULL;
2291     BlockDriverState *bottom_bs = NULL;
2292     AioContext *aio_context;
2293     Error *local_err = NULL;
2294     int job_flags = JOB_DEFAULT;
2295 
2296     GLOBAL_STATE_CODE();
2297 
2298     if (base && base_node) {
2299         error_setg(errp, "'base' and 'base-node' cannot be specified "
2300                    "at the same time");
2301         return;
2302     }
2303 
2304     if (base && bottom) {
2305         error_setg(errp, "'base' and 'bottom' cannot be specified "
2306                    "at the same time");
2307         return;
2308     }
2309 
2310     if (bottom && base_node) {
2311         error_setg(errp, "'bottom' and 'base-node' cannot be specified "
2312                    "at the same time");
2313         return;
2314     }
2315 
2316     if (!has_on_error) {
2317         on_error = BLOCKDEV_ON_ERROR_REPORT;
2318     }
2319 
2320     bs = bdrv_lookup_bs(device, device, errp);
2321     if (!bs) {
2322         return;
2323     }
2324 
2325     aio_context = bdrv_get_aio_context(bs);
2326 
2327     bdrv_graph_rdlock_main_loop();
2328     if (base) {
2329         base_bs = bdrv_find_backing_image(bs, base);
2330         if (base_bs == NULL) {
2331             error_setg(errp, "Can't find '%s' in the backing chain", base);
2332             goto out_rdlock;
2333         }
2334         assert(bdrv_get_aio_context(base_bs) == aio_context);
2335     }
2336 
2337     if (base_node) {
2338         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2339         if (!base_bs) {
2340             goto out_rdlock;
2341         }
2342         if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
2343             error_setg(errp, "Node '%s' is not a backing image of '%s'",
2344                        base_node, device);
2345             goto out_rdlock;
2346         }
2347         assert(bdrv_get_aio_context(base_bs) == aio_context);
2348 
2349         bdrv_refresh_filename(base_bs);
2350     }
2351 
2352     if (bottom) {
2353         bottom_bs = bdrv_lookup_bs(NULL, bottom, errp);
2354         if (!bottom_bs) {
2355             goto out_rdlock;
2356         }
2357         if (!bottom_bs->drv) {
2358             error_setg(errp, "Node '%s' is not open", bottom);
2359             goto out_rdlock;
2360         }
2361         if (bottom_bs->drv->is_filter) {
2362             error_setg(errp, "Node '%s' is a filter, use a non-filter node "
2363                        "as 'bottom'", bottom);
2364             goto out_rdlock;
2365         }
2366         if (!bdrv_chain_contains(bs, bottom_bs)) {
2367             error_setg(errp, "Node '%s' is not in a chain starting from '%s'",
2368                        bottom, device);
2369             goto out_rdlock;
2370         }
2371         assert(bdrv_get_aio_context(bottom_bs) == aio_context);
2372     }
2373 
2374     /*
2375      * Check for op blockers in the whole chain between bs and base (or bottom)
2376      */
2377     iter_end = bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
2378     for (iter = bs; iter && iter != iter_end;
2379          iter = bdrv_filter_or_cow_bs(iter))
2380     {
2381         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
2382             goto out_rdlock;
2383         }
2384     }
2385     bdrv_graph_rdunlock_main_loop();
2386 
2387     /* if we are streaming the entire chain, the result will have no backing
2388      * file, and specifying one is therefore an error */
2389     if (!base_bs && backing_file) {
2390         error_setg(errp, "backing file specified, but streaming the "
2391                          "entire chain");
2392         return;
2393     }
2394 
2395     if (has_auto_finalize && !auto_finalize) {
2396         job_flags |= JOB_MANUAL_FINALIZE;
2397     }
2398     if (has_auto_dismiss && !auto_dismiss) {
2399         job_flags |= JOB_MANUAL_DISMISS;
2400     }
2401 
2402     stream_start(job_id, bs, base_bs, backing_file,
2403                  bottom_bs, job_flags, has_speed ? speed : 0, on_error,
2404                  filter_node_name, &local_err);
2405     if (local_err) {
2406         error_propagate(errp, local_err);
2407         return;
2408     }
2409 
2410     trace_qmp_block_stream(bs);
2411     return;
2412 
2413 out_rdlock:
2414     bdrv_graph_rdunlock_main_loop();
2415 }
2416 
2417 void qmp_block_commit(const char *job_id, const char *device,
2418                       const char *base_node,
2419                       const char *base,
2420                       const char *top_node,
2421                       const char *top,
2422                       const char *backing_file,
2423                       bool has_speed, int64_t speed,
2424                       bool has_on_error, BlockdevOnError on_error,
2425                       const char *filter_node_name,
2426                       bool has_auto_finalize, bool auto_finalize,
2427                       bool has_auto_dismiss, bool auto_dismiss,
2428                       Error **errp)
2429 {
2430     BlockDriverState *bs;
2431     BlockDriverState *iter;
2432     BlockDriverState *base_bs, *top_bs;
2433     AioContext *aio_context;
2434     Error *local_err = NULL;
2435     int job_flags = JOB_DEFAULT;
2436     uint64_t top_perm, top_shared;
2437 
2438     /* TODO We'll eventually have to take a writer lock in this function */
2439     GRAPH_RDLOCK_GUARD_MAINLOOP();
2440 
2441     if (!has_speed) {
2442         speed = 0;
2443     }
2444     if (!has_on_error) {
2445         on_error = BLOCKDEV_ON_ERROR_REPORT;
2446     }
2447     if (has_auto_finalize && !auto_finalize) {
2448         job_flags |= JOB_MANUAL_FINALIZE;
2449     }
2450     if (has_auto_dismiss && !auto_dismiss) {
2451         job_flags |= JOB_MANUAL_DISMISS;
2452     }
2453 
2454     /* Important Note:
2455      *  libvirt relies on the DeviceNotFound error class in order to probe for
2456      *  live commit feature versions; for this to work, we must make sure to
2457      *  perform the device lookup before any generic errors that may occur in a
2458      *  scenario in which all optional arguments are omitted. */
2459     bs = qmp_get_root_bs(device, &local_err);
2460     if (!bs) {
2461         bs = bdrv_lookup_bs(device, device, NULL);
2462         if (!bs) {
2463             error_free(local_err);
2464             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
2465                       "Device '%s' not found", device);
2466         } else {
2467             error_propagate(errp, local_err);
2468         }
2469         return;
2470     }
2471 
2472     aio_context = bdrv_get_aio_context(bs);
2473 
2474     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
2475         return;
2476     }
2477 
2478     /* default top_bs is the active layer */
2479     top_bs = bs;
2480 
2481     if (top_node && top) {
2482         error_setg(errp, "'top-node' and 'top' are mutually exclusive");
2483         return;
2484     } else if (top_node) {
2485         top_bs = bdrv_lookup_bs(NULL, top_node, errp);
2486         if (top_bs == NULL) {
2487             return;
2488         }
2489         if (!bdrv_chain_contains(bs, top_bs)) {
2490             error_setg(errp, "'%s' is not in this backing file chain",
2491                        top_node);
2492             return;
2493         }
2494     } else if (top) {
2495         /* This strcmp() is just a shortcut, there is no need to
2496          * refresh @bs's filename.  If it mismatches,
2497          * bdrv_find_backing_image() will do the refresh and may still
2498          * return @bs. */
2499         if (strcmp(bs->filename, top) != 0) {
2500             top_bs = bdrv_find_backing_image(bs, top);
2501         }
2502     }
2503 
2504     if (top_bs == NULL) {
2505         error_setg(errp, "Top image file %s not found", top ? top : "NULL");
2506         return;
2507     }
2508 
2509     assert(bdrv_get_aio_context(top_bs) == aio_context);
2510 
2511     if (base_node && base) {
2512         error_setg(errp, "'base-node' and 'base' are mutually exclusive");
2513         return;
2514     } else if (base_node) {
2515         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2516         if (base_bs == NULL) {
2517             return;
2518         }
2519         if (!bdrv_chain_contains(top_bs, base_bs)) {
2520             error_setg(errp, "'%s' is not in this backing file chain",
2521                        base_node);
2522             return;
2523         }
2524     } else if (base) {
2525         base_bs = bdrv_find_backing_image(top_bs, base);
2526         if (base_bs == NULL) {
2527             error_setg(errp, "Can't find '%s' in the backing chain", base);
2528             return;
2529         }
2530     } else {
2531         base_bs = bdrv_find_base(top_bs);
2532         if (base_bs == NULL) {
2533             error_setg(errp, "There is no backimg image");
2534             return;
2535         }
2536     }
2537 
2538     assert(bdrv_get_aio_context(base_bs) == aio_context);
2539 
2540     for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
2541          iter = bdrv_filter_or_cow_bs(iter))
2542     {
2543         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2544             return;
2545         }
2546     }
2547 
2548     /* Do not allow attempts to commit an image into itself */
2549     if (top_bs == base_bs) {
2550         error_setg(errp, "cannot commit an image into itself");
2551         return;
2552     }
2553 
2554     /*
2555      * Active commit is required if and only if someone has taken a
2556      * WRITE permission on the top node.  Historically, we have always
2557      * used active commit for top nodes, so continue that practice
2558      * lest we possibly break clients that rely on this behavior, e.g.
2559      * to later attach this node to a writing parent.
2560      * (Active commit is never really wrong.)
2561      */
2562     bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared);
2563     if (top_perm & BLK_PERM_WRITE ||
2564         bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs))
2565     {
2566         if (backing_file) {
2567             if (bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs)) {
2568                 error_setg(errp, "'backing-file' specified,"
2569                                  " but 'top' is the active layer");
2570             } else {
2571                 error_setg(errp, "'backing-file' specified, but 'top' has a "
2572                                  "writer on it");
2573             }
2574             return;
2575         }
2576         if (!job_id) {
2577             /*
2578              * Emulate here what block_job_create() does, because it
2579              * is possible that @bs != @top_bs (the block job should
2580              * be named after @bs, even if @top_bs is the actual
2581              * source)
2582              */
2583             job_id = bdrv_get_device_name(bs);
2584         }
2585         commit_active_start(job_id, top_bs, base_bs, job_flags, speed, on_error,
2586                             filter_node_name, NULL, NULL, false, &local_err);
2587     } else {
2588         BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
2589         if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2590             return;
2591         }
2592         commit_start(job_id, bs, base_bs, top_bs, job_flags,
2593                      speed, on_error, backing_file,
2594                      filter_node_name, &local_err);
2595     }
2596     if (local_err != NULL) {
2597         error_propagate(errp, local_err);
2598         return;
2599     }
2600 }
2601 
2602 /* Common QMP interface for drive-backup and blockdev-backup */
2603 static BlockJob *do_backup_common(BackupCommon *backup,
2604                                   BlockDriverState *bs,
2605                                   BlockDriverState *target_bs,
2606                                   AioContext *aio_context,
2607                                   JobTxn *txn, Error **errp)
2608 {
2609     BlockJob *job = NULL;
2610     BdrvDirtyBitmap *bmap = NULL;
2611     BackupPerf perf = { .max_workers = 64 };
2612     int job_flags = JOB_DEFAULT;
2613 
2614     if (!backup->has_speed) {
2615         backup->speed = 0;
2616     }
2617     if (!backup->has_on_source_error) {
2618         backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2619     }
2620     if (!backup->has_on_target_error) {
2621         backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2622     }
2623     if (!backup->has_auto_finalize) {
2624         backup->auto_finalize = true;
2625     }
2626     if (!backup->has_auto_dismiss) {
2627         backup->auto_dismiss = true;
2628     }
2629     if (!backup->has_compress) {
2630         backup->compress = false;
2631     }
2632 
2633     if (backup->x_perf) {
2634         if (backup->x_perf->has_use_copy_range) {
2635             perf.use_copy_range = backup->x_perf->use_copy_range;
2636         }
2637         if (backup->x_perf->has_max_workers) {
2638             perf.max_workers = backup->x_perf->max_workers;
2639         }
2640         if (backup->x_perf->has_max_chunk) {
2641             perf.max_chunk = backup->x_perf->max_chunk;
2642         }
2643     }
2644 
2645     if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) ||
2646         (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL)) {
2647         /* done before desugaring 'incremental' to print the right message */
2648         if (!backup->bitmap) {
2649             error_setg(errp, "must provide a valid bitmap name for "
2650                        "'%s' sync mode", MirrorSyncMode_str(backup->sync));
2651             return NULL;
2652         }
2653     }
2654 
2655     if (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL) {
2656         if (backup->has_bitmap_mode &&
2657             backup->bitmap_mode != BITMAP_SYNC_MODE_ON_SUCCESS) {
2658             error_setg(errp, "Bitmap sync mode must be '%s' "
2659                        "when using sync mode '%s'",
2660                        BitmapSyncMode_str(BITMAP_SYNC_MODE_ON_SUCCESS),
2661                        MirrorSyncMode_str(backup->sync));
2662             return NULL;
2663         }
2664         backup->has_bitmap_mode = true;
2665         backup->sync = MIRROR_SYNC_MODE_BITMAP;
2666         backup->bitmap_mode = BITMAP_SYNC_MODE_ON_SUCCESS;
2667     }
2668 
2669     if (backup->bitmap) {
2670         bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
2671         if (!bmap) {
2672             error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
2673             return NULL;
2674         }
2675         if (!backup->has_bitmap_mode) {
2676             error_setg(errp, "Bitmap sync mode must be given "
2677                        "when providing a bitmap");
2678             return NULL;
2679         }
2680         if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2681             return NULL;
2682         }
2683 
2684         /* This does not produce a useful bitmap artifact: */
2685         if (backup->sync == MIRROR_SYNC_MODE_NONE) {
2686             error_setg(errp, "sync mode '%s' does not produce meaningful bitmap"
2687                        " outputs", MirrorSyncMode_str(backup->sync));
2688             return NULL;
2689         }
2690 
2691         /* If the bitmap isn't used for input or output, this is useless: */
2692         if (backup->bitmap_mode == BITMAP_SYNC_MODE_NEVER &&
2693             backup->sync != MIRROR_SYNC_MODE_BITMAP) {
2694             error_setg(errp, "Bitmap sync mode '%s' has no meaningful effect"
2695                        " when combined with sync mode '%s'",
2696                        BitmapSyncMode_str(backup->bitmap_mode),
2697                        MirrorSyncMode_str(backup->sync));
2698             return NULL;
2699         }
2700     }
2701 
2702     if (!backup->bitmap && backup->has_bitmap_mode) {
2703         error_setg(errp, "Cannot specify bitmap sync mode without a bitmap");
2704         return NULL;
2705     }
2706 
2707     if (!backup->auto_finalize) {
2708         job_flags |= JOB_MANUAL_FINALIZE;
2709     }
2710     if (!backup->auto_dismiss) {
2711         job_flags |= JOB_MANUAL_DISMISS;
2712     }
2713 
2714     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
2715                             backup->sync, bmap, backup->bitmap_mode,
2716                             backup->compress,
2717                             backup->filter_node_name,
2718                             &perf,
2719                             backup->on_source_error,
2720                             backup->on_target_error,
2721                             job_flags, NULL, NULL, txn, errp);
2722     return job;
2723 }
2724 
2725 void qmp_drive_backup(DriveBackup *backup, Error **errp)
2726 {
2727     TransactionAction action = {
2728         .type = TRANSACTION_ACTION_KIND_DRIVE_BACKUP,
2729         .u.drive_backup.data = backup,
2730     };
2731     blockdev_do_action(&action, errp);
2732 }
2733 
2734 BlockDeviceInfoList *qmp_query_named_block_nodes(bool has_flat,
2735                                                  bool flat,
2736                                                  Error **errp)
2737 {
2738     bool return_flat = has_flat && flat;
2739 
2740     return bdrv_named_nodes_list(return_flat, errp);
2741 }
2742 
2743 XDbgBlockGraph *qmp_x_debug_query_block_graph(Error **errp)
2744 {
2745     GRAPH_RDLOCK_GUARD_MAINLOOP();
2746 
2747     return bdrv_get_xdbg_block_graph(errp);
2748 }
2749 
2750 void qmp_blockdev_backup(BlockdevBackup *backup, Error **errp)
2751 {
2752     TransactionAction action = {
2753         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP,
2754         .u.blockdev_backup.data = backup,
2755     };
2756     blockdev_do_action(&action, errp);
2757 }
2758 
2759 /* Parameter check and block job starting for drive mirroring.
2760  * Caller should hold @device and @target's aio context (must be the same).
2761  **/
2762 static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
2763                                    BlockDriverState *target,
2764                                    const char *replaces,
2765                                    enum MirrorSyncMode sync,
2766                                    BlockMirrorBackingMode backing_mode,
2767                                    bool zero_target,
2768                                    bool has_speed, int64_t speed,
2769                                    bool has_granularity, uint32_t granularity,
2770                                    bool has_buf_size, int64_t buf_size,
2771                                    bool has_on_source_error,
2772                                    BlockdevOnError on_source_error,
2773                                    bool has_on_target_error,
2774                                    BlockdevOnError on_target_error,
2775                                    bool has_unmap, bool unmap,
2776                                    const char *filter_node_name,
2777                                    bool has_copy_mode, MirrorCopyMode copy_mode,
2778                                    bool has_auto_finalize, bool auto_finalize,
2779                                    bool has_auto_dismiss, bool auto_dismiss,
2780                                    Error **errp)
2781 {
2782     BlockDriverState *unfiltered_bs;
2783     int job_flags = JOB_DEFAULT;
2784 
2785     GLOBAL_STATE_CODE();
2786     GRAPH_RDLOCK_GUARD_MAINLOOP();
2787 
2788     if (!has_speed) {
2789         speed = 0;
2790     }
2791     if (!has_on_source_error) {
2792         on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2793     }
2794     if (!has_on_target_error) {
2795         on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2796     }
2797     if (!has_granularity) {
2798         granularity = 0;
2799     }
2800     if (!has_buf_size) {
2801         buf_size = 0;
2802     }
2803     if (!has_unmap) {
2804         unmap = true;
2805     }
2806     if (!has_copy_mode) {
2807         copy_mode = MIRROR_COPY_MODE_BACKGROUND;
2808     }
2809     if (has_auto_finalize && !auto_finalize) {
2810         job_flags |= JOB_MANUAL_FINALIZE;
2811     }
2812     if (has_auto_dismiss && !auto_dismiss) {
2813         job_flags |= JOB_MANUAL_DISMISS;
2814     }
2815 
2816     if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
2817         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2818                    "a value in range [512B, 64MB]");
2819         return;
2820     }
2821     if (granularity & (granularity - 1)) {
2822         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2823                    "a power of 2");
2824         return;
2825     }
2826 
2827     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2828         return;
2829     }
2830     if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
2831         return;
2832     }
2833 
2834     if (!bdrv_backing_chain_next(bs) && sync == MIRROR_SYNC_MODE_TOP) {
2835         sync = MIRROR_SYNC_MODE_FULL;
2836     }
2837 
2838     if (!replaces) {
2839         /* We want to mirror from @bs, but keep implicit filters on top */
2840         unfiltered_bs = bdrv_skip_implicit_filters(bs);
2841         if (unfiltered_bs != bs) {
2842             replaces = unfiltered_bs->node_name;
2843         }
2844     }
2845 
2846     if (replaces) {
2847         BlockDriverState *to_replace_bs;
2848         int64_t bs_size, replace_size;
2849 
2850         bs_size = bdrv_getlength(bs);
2851         if (bs_size < 0) {
2852             error_setg_errno(errp, -bs_size, "Failed to query device's size");
2853             return;
2854         }
2855 
2856         to_replace_bs = check_to_replace_node(bs, replaces, errp);
2857         if (!to_replace_bs) {
2858             return;
2859         }
2860 
2861         replace_size = bdrv_getlength(to_replace_bs);
2862 
2863         if (replace_size < 0) {
2864             error_setg_errno(errp, -replace_size,
2865                              "Failed to query the replacement node's size");
2866             return;
2867         }
2868         if (bs_size != replace_size) {
2869             error_setg(errp, "cannot replace image with a mirror image of "
2870                              "different size");
2871             return;
2872         }
2873     }
2874 
2875     /* pass the node name to replace to mirror start since it's loose coupling
2876      * and will allow to check whether the node still exist at mirror completion
2877      */
2878     mirror_start(job_id, bs, target,
2879                  replaces, job_flags,
2880                  speed, granularity, buf_size, sync, backing_mode, zero_target,
2881                  on_source_error, on_target_error, unmap, filter_node_name,
2882                  copy_mode, errp);
2883 }
2884 
2885 void qmp_drive_mirror(DriveMirror *arg, Error **errp)
2886 {
2887     BlockDriverState *bs;
2888     BlockDriverState *target_backing_bs, *target_bs;
2889     AioContext *aio_context;
2890     BlockMirrorBackingMode backing_mode;
2891     Error *local_err = NULL;
2892     QDict *options = NULL;
2893     int flags;
2894     int64_t size;
2895     const char *format = arg->format;
2896     bool zero_target;
2897     int ret;
2898 
2899     bs = qmp_get_root_bs(arg->device, errp);
2900     if (!bs) {
2901         return;
2902     }
2903 
2904     /* Early check to avoid creating target */
2905     bdrv_graph_rdlock_main_loop();
2906     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2907         bdrv_graph_rdunlock_main_loop();
2908         return;
2909     }
2910 
2911     aio_context = bdrv_get_aio_context(bs);
2912 
2913     if (!arg->has_mode) {
2914         arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
2915     }
2916 
2917     if (!arg->format) {
2918         format = (arg->mode == NEW_IMAGE_MODE_EXISTING
2919                   ? NULL : bs->drv->format_name);
2920     }
2921 
2922     flags = bs->open_flags | BDRV_O_RDWR;
2923     target_backing_bs = bdrv_cow_bs(bdrv_skip_filters(bs));
2924     if (!target_backing_bs && arg->sync == MIRROR_SYNC_MODE_TOP) {
2925         arg->sync = MIRROR_SYNC_MODE_FULL;
2926     }
2927     if (arg->sync == MIRROR_SYNC_MODE_NONE) {
2928         target_backing_bs = bs;
2929     }
2930     bdrv_graph_rdunlock_main_loop();
2931 
2932     size = bdrv_getlength(bs);
2933     if (size < 0) {
2934         error_setg_errno(errp, -size, "bdrv_getlength failed");
2935         return;
2936     }
2937 
2938     if (arg->replaces) {
2939         if (!arg->node_name) {
2940             error_setg(errp, "a node-name must be provided when replacing a"
2941                              " named node of the graph");
2942             return;
2943         }
2944     }
2945 
2946     if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
2947         backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
2948     } else {
2949         backing_mode = MIRROR_OPEN_BACKING_CHAIN;
2950     }
2951 
2952     /* Don't open backing image in create() */
2953     flags |= BDRV_O_NO_BACKING;
2954 
2955     if ((arg->sync == MIRROR_SYNC_MODE_FULL || !target_backing_bs)
2956         && arg->mode != NEW_IMAGE_MODE_EXISTING)
2957     {
2958         /* create new image w/o backing file */
2959         assert(format);
2960         bdrv_img_create(arg->target, format,
2961                         NULL, NULL, NULL, size, flags, false, &local_err);
2962     } else {
2963         BlockDriverState *explicit_backing;
2964 
2965         switch (arg->mode) {
2966         case NEW_IMAGE_MODE_EXISTING:
2967             break;
2968         case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
2969             /*
2970              * Create new image with backing file.
2971              * Implicit filters should not appear in the filename.
2972              */
2973             bdrv_graph_rdlock_main_loop();
2974             explicit_backing = bdrv_skip_implicit_filters(target_backing_bs);
2975             bdrv_refresh_filename(explicit_backing);
2976             bdrv_graph_rdunlock_main_loop();
2977 
2978             bdrv_img_create(arg->target, format,
2979                             explicit_backing->filename,
2980                             explicit_backing->drv->format_name,
2981                             NULL, size, flags, false, &local_err);
2982             break;
2983         default:
2984             abort();
2985         }
2986     }
2987 
2988     if (local_err) {
2989         error_propagate(errp, local_err);
2990         return;
2991     }
2992 
2993     options = qdict_new();
2994     if (arg->node_name) {
2995         qdict_put_str(options, "node-name", arg->node_name);
2996     }
2997     if (format) {
2998         qdict_put_str(options, "driver", format);
2999     }
3000 
3001     /* Mirroring takes care of copy-on-write using the source's backing
3002      * file.
3003      */
3004     target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
3005     if (!target_bs) {
3006         return;
3007     }
3008 
3009     bdrv_graph_rdlock_main_loop();
3010     zero_target = (arg->sync == MIRROR_SYNC_MODE_FULL &&
3011                    (arg->mode == NEW_IMAGE_MODE_EXISTING ||
3012                     !bdrv_has_zero_init(target_bs)));
3013     bdrv_graph_rdunlock_main_loop();
3014 
3015 
3016     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3017     if (ret < 0) {
3018         bdrv_unref(target_bs);
3019         return;
3020     }
3021 
3022     blockdev_mirror_common(arg->job_id, bs, target_bs,
3023                            arg->replaces, arg->sync,
3024                            backing_mode, zero_target,
3025                            arg->has_speed, arg->speed,
3026                            arg->has_granularity, arg->granularity,
3027                            arg->has_buf_size, arg->buf_size,
3028                            arg->has_on_source_error, arg->on_source_error,
3029                            arg->has_on_target_error, arg->on_target_error,
3030                            arg->has_unmap, arg->unmap,
3031                            NULL,
3032                            arg->has_copy_mode, arg->copy_mode,
3033                            arg->has_auto_finalize, arg->auto_finalize,
3034                            arg->has_auto_dismiss, arg->auto_dismiss,
3035                            errp);
3036     bdrv_unref(target_bs);
3037 }
3038 
3039 void qmp_blockdev_mirror(const char *job_id,
3040                          const char *device, const char *target,
3041                          const char *replaces,
3042                          MirrorSyncMode sync,
3043                          bool has_speed, int64_t speed,
3044                          bool has_granularity, uint32_t granularity,
3045                          bool has_buf_size, int64_t buf_size,
3046                          bool has_on_source_error,
3047                          BlockdevOnError on_source_error,
3048                          bool has_on_target_error,
3049                          BlockdevOnError on_target_error,
3050                          const char *filter_node_name,
3051                          bool has_copy_mode, MirrorCopyMode copy_mode,
3052                          bool has_auto_finalize, bool auto_finalize,
3053                          bool has_auto_dismiss, bool auto_dismiss,
3054                          Error **errp)
3055 {
3056     BlockDriverState *bs;
3057     BlockDriverState *target_bs;
3058     AioContext *aio_context;
3059     BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
3060     bool zero_target;
3061     int ret;
3062 
3063     bs = qmp_get_root_bs(device, errp);
3064     if (!bs) {
3065         return;
3066     }
3067 
3068     target_bs = bdrv_lookup_bs(target, target, errp);
3069     if (!target_bs) {
3070         return;
3071     }
3072 
3073     zero_target = (sync == MIRROR_SYNC_MODE_FULL);
3074 
3075     aio_context = bdrv_get_aio_context(bs);
3076 
3077     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3078     if (ret < 0) {
3079         return;
3080     }
3081 
3082     blockdev_mirror_common(job_id, bs, target_bs,
3083                            replaces, sync, backing_mode,
3084                            zero_target, has_speed, speed,
3085                            has_granularity, granularity,
3086                            has_buf_size, buf_size,
3087                            has_on_source_error, on_source_error,
3088                            has_on_target_error, on_target_error,
3089                            true, true, filter_node_name,
3090                            has_copy_mode, copy_mode,
3091                            has_auto_finalize, auto_finalize,
3092                            has_auto_dismiss, auto_dismiss,
3093                            errp);
3094 }
3095 
3096 /*
3097  * Get a block job using its ID. Called with job_mutex held.
3098  */
3099 static BlockJob *find_block_job_locked(const char *id, Error **errp)
3100 {
3101     BlockJob *job;
3102 
3103     assert(id != NULL);
3104 
3105     job = block_job_get_locked(id);
3106 
3107     if (!job) {
3108         error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
3109                   "Block job '%s' not found", id);
3110         return NULL;
3111     }
3112 
3113     return job;
3114 }
3115 
3116 void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
3117 {
3118     BlockJob *job;
3119 
3120     JOB_LOCK_GUARD();
3121     job = find_block_job_locked(device, errp);
3122 
3123     if (!job) {
3124         return;
3125     }
3126 
3127     block_job_set_speed_locked(job, speed, errp);
3128 }
3129 
3130 void qmp_block_job_cancel(const char *device,
3131                           bool has_force, bool force, Error **errp)
3132 {
3133     BlockJob *job;
3134 
3135     JOB_LOCK_GUARD();
3136     job = find_block_job_locked(device, errp);
3137 
3138     if (!job) {
3139         return;
3140     }
3141 
3142     if (!has_force) {
3143         force = false;
3144     }
3145 
3146     if (job_user_paused_locked(&job->job) && !force) {
3147         error_setg(errp, "The block job for device '%s' is currently paused",
3148                    device);
3149         return;
3150     }
3151 
3152     trace_qmp_block_job_cancel(job);
3153     job_user_cancel_locked(&job->job, force, errp);
3154 }
3155 
3156 void qmp_block_job_pause(const char *device, Error **errp)
3157 {
3158     BlockJob *job;
3159 
3160     JOB_LOCK_GUARD();
3161     job = find_block_job_locked(device, errp);
3162 
3163     if (!job) {
3164         return;
3165     }
3166 
3167     trace_qmp_block_job_pause(job);
3168     job_user_pause_locked(&job->job, errp);
3169 }
3170 
3171 void qmp_block_job_resume(const char *device, Error **errp)
3172 {
3173     BlockJob *job;
3174 
3175     JOB_LOCK_GUARD();
3176     job = find_block_job_locked(device, errp);
3177 
3178     if (!job) {
3179         return;
3180     }
3181 
3182     trace_qmp_block_job_resume(job);
3183     job_user_resume_locked(&job->job, errp);
3184 }
3185 
3186 void qmp_block_job_complete(const char *device, Error **errp)
3187 {
3188     BlockJob *job;
3189 
3190     JOB_LOCK_GUARD();
3191     job = find_block_job_locked(device, errp);
3192 
3193     if (!job) {
3194         return;
3195     }
3196 
3197     trace_qmp_block_job_complete(job);
3198     job_complete_locked(&job->job, errp);
3199 }
3200 
3201 void qmp_block_job_finalize(const char *id, Error **errp)
3202 {
3203     BlockJob *job;
3204 
3205     JOB_LOCK_GUARD();
3206     job = find_block_job_locked(id, errp);
3207 
3208     if (!job) {
3209         return;
3210     }
3211 
3212     trace_qmp_block_job_finalize(job);
3213     job_ref_locked(&job->job);
3214     job_finalize_locked(&job->job, errp);
3215 
3216     job_unref_locked(&job->job);
3217 }
3218 
3219 void qmp_block_job_dismiss(const char *id, Error **errp)
3220 {
3221     BlockJob *bjob;
3222     Job *job;
3223 
3224     JOB_LOCK_GUARD();
3225     bjob = find_block_job_locked(id, errp);
3226 
3227     if (!bjob) {
3228         return;
3229     }
3230 
3231     trace_qmp_block_job_dismiss(bjob);
3232     job = &bjob->job;
3233     job_dismiss_locked(&job, errp);
3234 }
3235 
3236 void qmp_block_job_change(BlockJobChangeOptions *opts, Error **errp)
3237 {
3238     BlockJob *job;
3239 
3240     JOB_LOCK_GUARD();
3241     job = find_block_job_locked(opts->id, errp);
3242 
3243     if (!job) {
3244         return;
3245     }
3246 
3247     block_job_change_locked(job, opts, errp);
3248 }
3249 
3250 void qmp_change_backing_file(const char *device,
3251                              const char *image_node_name,
3252                              const char *backing_file,
3253                              Error **errp)
3254 {
3255     BlockDriverState *bs = NULL;
3256     BlockDriverState *image_bs = NULL;
3257     Error *local_err = NULL;
3258     bool ro;
3259     int ret;
3260 
3261     bs = qmp_get_root_bs(device, errp);
3262     if (!bs) {
3263         return;
3264     }
3265 
3266     bdrv_graph_rdlock_main_loop();
3267 
3268     image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
3269     if (local_err) {
3270         error_propagate(errp, local_err);
3271         goto out_rdlock;
3272     }
3273 
3274     if (!image_bs) {
3275         error_setg(errp, "image file not found");
3276         goto out_rdlock;
3277     }
3278 
3279     if (bdrv_find_base(image_bs) == image_bs) {
3280         error_setg(errp, "not allowing backing file change on an image "
3281                          "without a backing file");
3282         goto out_rdlock;
3283     }
3284 
3285     /* even though we are not necessarily operating on bs, we need it to
3286      * determine if block ops are currently prohibited on the chain */
3287     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
3288         goto out_rdlock;
3289     }
3290 
3291     /* final sanity check */
3292     if (!bdrv_chain_contains(bs, image_bs)) {
3293         error_setg(errp, "'%s' and image file are not in the same chain",
3294                    device);
3295         goto out_rdlock;
3296     }
3297     bdrv_graph_rdunlock_main_loop();
3298 
3299     /* if not r/w, reopen to make r/w */
3300     ro = bdrv_is_read_only(image_bs);
3301 
3302     if (ro) {
3303         if (bdrv_reopen_set_read_only(image_bs, false, errp) != 0) {
3304             return;
3305         }
3306     }
3307 
3308     ret = bdrv_change_backing_file(image_bs, backing_file,
3309                                    image_bs->drv ? image_bs->drv->format_name : "",
3310                                    false);
3311 
3312     if (ret < 0) {
3313         error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
3314                          backing_file);
3315         /* don't exit here, so we can try to restore open flags if
3316          * appropriate */
3317     }
3318 
3319     if (ro) {
3320         bdrv_reopen_set_read_only(image_bs, true, errp);
3321     }
3322     return;
3323 
3324 out_rdlock:
3325     bdrv_graph_rdunlock_main_loop();
3326 }
3327 
3328 void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
3329 {
3330     BlockDriverState *bs;
3331     QObject *obj;
3332     Visitor *v = qobject_output_visitor_new(&obj);
3333     QDict *qdict;
3334 
3335     visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3336     visit_complete(v, &obj);
3337     qdict = qobject_to(QDict, obj);
3338 
3339     qdict_flatten(qdict);
3340 
3341     if (!qdict_get_try_str(qdict, "node-name")) {
3342         error_setg(errp, "'node-name' must be specified for the root node");
3343         goto fail;
3344     }
3345 
3346     bs = bds_tree_init(qdict, errp);
3347     if (!bs) {
3348         goto fail;
3349     }
3350 
3351     bdrv_set_monitor_owned(bs);
3352 
3353 fail:
3354     visit_free(v);
3355 }
3356 
3357 void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
3358 {
3359     BlockReopenQueue *queue = NULL;
3360 
3361     /* Add each one of the BDS that we want to reopen to the queue */
3362     for (; reopen_list != NULL; reopen_list = reopen_list->next) {
3363         BlockdevOptions *options = reopen_list->value;
3364         BlockDriverState *bs;
3365         QObject *obj;
3366         Visitor *v;
3367         QDict *qdict;
3368 
3369         /* Check for the selected node name */
3370         if (!options->node_name) {
3371             error_setg(errp, "node-name not specified");
3372             goto fail;
3373         }
3374 
3375         bs = bdrv_find_node(options->node_name);
3376         if (!bs) {
3377             error_setg(errp, "Failed to find node with node-name='%s'",
3378                        options->node_name);
3379             goto fail;
3380         }
3381 
3382         /* Put all options in a QDict and flatten it */
3383         v = qobject_output_visitor_new(&obj);
3384         visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3385         visit_complete(v, &obj);
3386         visit_free(v);
3387 
3388         qdict = qobject_to(QDict, obj);
3389 
3390         qdict_flatten(qdict);
3391 
3392         queue = bdrv_reopen_queue(queue, bs, qdict, false);
3393     }
3394 
3395     /* Perform the reopen operation */
3396     bdrv_reopen_multiple(queue, errp);
3397     queue = NULL;
3398 
3399 fail:
3400     bdrv_reopen_queue_free(queue);
3401 }
3402 
3403 void qmp_blockdev_del(const char *node_name, Error **errp)
3404 {
3405     BlockDriverState *bs;
3406 
3407     GLOBAL_STATE_CODE();
3408     GRAPH_RDLOCK_GUARD_MAINLOOP();
3409 
3410     bs = bdrv_find_node(node_name);
3411     if (!bs) {
3412         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3413         return;
3414     }
3415     if (bdrv_has_blk(bs)) {
3416         error_setg(errp, "Node %s is in use", node_name);
3417         return;
3418     }
3419 
3420     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
3421         return;
3422     }
3423 
3424     if (!QTAILQ_IN_USE(bs, monitor_list)) {
3425         error_setg(errp, "Node %s is not owned by the monitor",
3426                    bs->node_name);
3427         return;
3428     }
3429 
3430     if (bs->refcnt > 1) {
3431         error_setg(errp, "Block device %s is in use",
3432                    bdrv_get_device_or_node_name(bs));
3433         return;
3434     }
3435 
3436     QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
3437     bdrv_unref(bs);
3438 }
3439 
3440 static BdrvChild * GRAPH_RDLOCK
3441 bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
3442 {
3443     BdrvChild *child;
3444 
3445     QLIST_FOREACH(child, &parent_bs->children, next) {
3446         if (strcmp(child->name, child_name) == 0) {
3447             return child;
3448         }
3449     }
3450 
3451     return NULL;
3452 }
3453 
3454 void qmp_x_blockdev_change(const char *parent, const char *child,
3455                            const char *node, Error **errp)
3456 {
3457     BlockDriverState *parent_bs, *new_bs = NULL;
3458     BdrvChild *p_child;
3459 
3460     bdrv_graph_wrlock();
3461 
3462     parent_bs = bdrv_lookup_bs(parent, parent, errp);
3463     if (!parent_bs) {
3464         goto out;
3465     }
3466 
3467     if (!child == !node) {
3468         if (child) {
3469             error_setg(errp, "The parameters child and node are in conflict");
3470         } else {
3471             error_setg(errp, "Either child or node must be specified");
3472         }
3473         goto out;
3474     }
3475 
3476     if (child) {
3477         p_child = bdrv_find_child(parent_bs, child);
3478         if (!p_child) {
3479             error_setg(errp, "Node '%s' does not have child '%s'",
3480                        parent, child);
3481             goto out;
3482         }
3483         bdrv_del_child(parent_bs, p_child, errp);
3484     }
3485 
3486     if (node) {
3487         new_bs = bdrv_find_node(node);
3488         if (!new_bs) {
3489             error_setg(errp, "Node '%s' not found", node);
3490             goto out;
3491         }
3492         bdrv_add_child(parent_bs, new_bs, errp);
3493     }
3494 
3495 out:
3496     bdrv_graph_wrunlock();
3497 }
3498 
3499 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
3500 {
3501     BlockJobInfoList *head = NULL, **tail = &head;
3502     BlockJob *job;
3503 
3504     JOB_LOCK_GUARD();
3505 
3506     for (job = block_job_next_locked(NULL); job;
3507          job = block_job_next_locked(job)) {
3508         BlockJobInfo *value;
3509 
3510         if (block_job_is_internal(job)) {
3511             continue;
3512         }
3513         value = block_job_query_locked(job, errp);
3514         if (!value) {
3515             qapi_free_BlockJobInfoList(head);
3516             return NULL;
3517         }
3518         QAPI_LIST_APPEND(tail, value);
3519     }
3520 
3521     return head;
3522 }
3523 
3524 void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
3525                                  bool has_force, bool force, Error **errp)
3526 {
3527     AioContext *new_context;
3528     BlockDriverState *bs;
3529 
3530     GRAPH_RDLOCK_GUARD_MAINLOOP();
3531 
3532     bs = bdrv_find_node(node_name);
3533     if (!bs) {
3534         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3535         return;
3536     }
3537 
3538     /* Protects against accidents. */
3539     if (!(has_force && force) && bdrv_has_blk(bs)) {
3540         error_setg(errp, "Node %s is associated with a BlockBackend and could "
3541                          "be in use (use force=true to override this check)",
3542                          node_name);
3543         return;
3544     }
3545 
3546     if (iothread->type == QTYPE_QSTRING) {
3547         IOThread *obj = iothread_by_id(iothread->u.s);
3548         if (!obj) {
3549             error_setg(errp, "Cannot find iothread %s", iothread->u.s);
3550             return;
3551         }
3552 
3553         new_context = iothread_get_aio_context(obj);
3554     } else {
3555         new_context = qemu_get_aio_context();
3556     }
3557 
3558     bdrv_try_change_aio_context(bs, new_context, NULL, errp);
3559 }
3560 
3561 QemuOptsList qemu_common_drive_opts = {
3562     .name = "drive",
3563     .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
3564     .desc = {
3565         {
3566             .name = "snapshot",
3567             .type = QEMU_OPT_BOOL,
3568             .help = "enable/disable snapshot mode",
3569         },{
3570             .name = "aio",
3571             .type = QEMU_OPT_STRING,
3572             .help = "host AIO implementation (threads, native, io_uring)",
3573         },{
3574             .name = BDRV_OPT_CACHE_WB,
3575             .type = QEMU_OPT_BOOL,
3576             .help = "Enable writeback mode",
3577         },{
3578             .name = "format",
3579             .type = QEMU_OPT_STRING,
3580             .help = "disk format (raw, qcow2, ...)",
3581         },{
3582             .name = "rerror",
3583             .type = QEMU_OPT_STRING,
3584             .help = "read error action",
3585         },{
3586             .name = "werror",
3587             .type = QEMU_OPT_STRING,
3588             .help = "write error action",
3589         },{
3590             .name = BDRV_OPT_READ_ONLY,
3591             .type = QEMU_OPT_BOOL,
3592             .help = "open drive file as read-only",
3593         },
3594 
3595         THROTTLE_OPTS,
3596 
3597         {
3598             .name = "throttling.group",
3599             .type = QEMU_OPT_STRING,
3600             .help = "name of the block throttling group",
3601         },{
3602             .name = "copy-on-read",
3603             .type = QEMU_OPT_BOOL,
3604             .help = "copy read data from backing file into image file",
3605         },{
3606             .name = "detect-zeroes",
3607             .type = QEMU_OPT_STRING,
3608             .help = "try to optimize zero writes (off, on, unmap)",
3609         },{
3610             .name = "stats-account-invalid",
3611             .type = QEMU_OPT_BOOL,
3612             .help = "whether to account for invalid I/O operations "
3613                     "in the statistics",
3614         },{
3615             .name = "stats-account-failed",
3616             .type = QEMU_OPT_BOOL,
3617             .help = "whether to account for failed I/O operations "
3618                     "in the statistics",
3619         },
3620         { /* end of list */ }
3621     },
3622 };
3623 
3624 QemuOptsList qemu_drive_opts = {
3625     .name = "drive",
3626     .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
3627     .desc = {
3628         /*
3629          * no elements => accept any params
3630          * validation will happen later
3631          */
3632         { /* end of list */ }
3633     },
3634 };
3635