xref: /qemu/blockdev.c (revision 9277d81f)
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/qdict.h"
39 #include "block/throttle-groups.h"
40 #include "monitor/monitor.h"
41 #include "qemu/error-report.h"
42 #include "qemu/option.h"
43 #include "qemu/config-file.h"
44 #include "qapi/qapi-commands-block.h"
45 #include "qapi/qapi-commands-transaction.h"
46 #include "qapi/qapi-visit-block-core.h"
47 #include "qapi/qmp/qdict.h"
48 #include "qapi/qmp/qnum.h"
49 #include "qapi/qmp/qstring.h"
50 #include "qapi/error.h"
51 #include "qapi/qmp/qerror.h"
52 #include "qapi/qmp/qlist.h"
53 #include "qapi/qobject-output-visitor.h"
54 #include "sysemu/sysemu.h"
55 #include "sysemu/iothread.h"
56 #include "block/block_int.h"
57 #include "block/trace.h"
58 #include "sysemu/arch_init.h"
59 #include "sysemu/qtest.h"
60 #include "qemu/cutils.h"
61 #include "qemu/help_option.h"
62 #include "qemu/throttle-options.h"
63 
64 static QTAILQ_HEAD(, BlockDriverState) monitor_bdrv_states =
65     QTAILQ_HEAD_INITIALIZER(monitor_bdrv_states);
66 
67 static int do_open_tray(const char *blk_name, const char *qdev_id,
68                         bool force, Error **errp);
69 static void blockdev_remove_medium(bool has_device, const char *device,
70                                    bool has_id, const char *id, Error **errp);
71 static void blockdev_insert_medium(bool has_device, const char *device,
72                                    bool has_id, const char *id,
73                                    const char *node_name, Error **errp);
74 
75 static const char *const if_name[IF_COUNT] = {
76     [IF_NONE] = "none",
77     [IF_IDE] = "ide",
78     [IF_SCSI] = "scsi",
79     [IF_FLOPPY] = "floppy",
80     [IF_PFLASH] = "pflash",
81     [IF_MTD] = "mtd",
82     [IF_SD] = "sd",
83     [IF_VIRTIO] = "virtio",
84     [IF_XEN] = "xen",
85 };
86 
87 static int if_max_devs[IF_COUNT] = {
88     /*
89      * Do not change these numbers!  They govern how drive option
90      * index maps to unit and bus.  That mapping is ABI.
91      *
92      * All controllers used to implement if=T drives need to support
93      * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
94      * Otherwise, some index values map to "impossible" bus, unit
95      * values.
96      *
97      * For instance, if you change [IF_SCSI] to 255, -drive
98      * if=scsi,index=12 no longer means bus=1,unit=5, but
99      * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
100      * the drive can't be set up.  Regression.
101      */
102     [IF_IDE] = 2,
103     [IF_SCSI] = 7,
104 };
105 
106 /**
107  * Boards may call this to offer board-by-board overrides
108  * of the default, global values.
109  */
110 void override_max_devs(BlockInterfaceType type, int max_devs)
111 {
112     BlockBackend *blk;
113     DriveInfo *dinfo;
114 
115     if (max_devs <= 0) {
116         return;
117     }
118 
119     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
120         dinfo = blk_legacy_dinfo(blk);
121         if (dinfo->type == type) {
122             fprintf(stderr, "Cannot override units-per-bus property of"
123                     " the %s interface, because a drive of that type has"
124                     " already been added.\n", if_name[type]);
125             g_assert_not_reached();
126         }
127     }
128 
129     if_max_devs[type] = max_devs;
130 }
131 
132 /*
133  * We automatically delete the drive when a device using it gets
134  * unplugged.  Questionable feature, but we can't just drop it.
135  * Device models call blockdev_mark_auto_del() to schedule the
136  * automatic deletion, and generic qdev code calls blockdev_auto_del()
137  * when deletion is actually safe.
138  */
139 void blockdev_mark_auto_del(BlockBackend *blk)
140 {
141     DriveInfo *dinfo = blk_legacy_dinfo(blk);
142     BlockDriverState *bs = blk_bs(blk);
143     AioContext *aio_context;
144 
145     if (!dinfo) {
146         return;
147     }
148 
149     if (bs) {
150         aio_context = bdrv_get_aio_context(bs);
151         aio_context_acquire(aio_context);
152 
153         if (bs->job) {
154             job_cancel(&bs->job->job, false);
155         }
156 
157         aio_context_release(aio_context);
158     }
159 
160     dinfo->auto_del = 1;
161 }
162 
163 void blockdev_auto_del(BlockBackend *blk)
164 {
165     DriveInfo *dinfo = blk_legacy_dinfo(blk);
166 
167     if (dinfo && dinfo->auto_del) {
168         monitor_remove_blk(blk);
169         blk_unref(blk);
170     }
171 }
172 
173 /**
174  * Returns the current mapping of how many units per bus
175  * a particular interface can support.
176  *
177  *  A positive integer indicates n units per bus.
178  *  0 implies the mapping has not been established.
179  * -1 indicates an invalid BlockInterfaceType was given.
180  */
181 int drive_get_max_devs(BlockInterfaceType type)
182 {
183     if (type >= IF_IDE && type < IF_COUNT) {
184         return if_max_devs[type];
185     }
186 
187     return -1;
188 }
189 
190 static int drive_index_to_bus_id(BlockInterfaceType type, int index)
191 {
192     int max_devs = if_max_devs[type];
193     return max_devs ? index / max_devs : 0;
194 }
195 
196 static int drive_index_to_unit_id(BlockInterfaceType type, int index)
197 {
198     int max_devs = if_max_devs[type];
199     return max_devs ? index % max_devs : index;
200 }
201 
202 QemuOpts *drive_def(const char *optstr)
203 {
204     return qemu_opts_parse_noisily(qemu_find_opts("drive"), optstr, false);
205 }
206 
207 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
208                     const char *optstr)
209 {
210     QemuOpts *opts;
211 
212     opts = drive_def(optstr);
213     if (!opts) {
214         return NULL;
215     }
216     if (type != IF_DEFAULT) {
217         qemu_opt_set(opts, "if", if_name[type], &error_abort);
218     }
219     if (index >= 0) {
220         qemu_opt_set_number(opts, "index", index, &error_abort);
221     }
222     if (file)
223         qemu_opt_set(opts, "file", file, &error_abort);
224     return opts;
225 }
226 
227 DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
228 {
229     BlockBackend *blk;
230     DriveInfo *dinfo;
231 
232     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
233         dinfo = blk_legacy_dinfo(blk);
234         if (dinfo && dinfo->type == type
235             && dinfo->bus == bus && dinfo->unit == unit) {
236             return dinfo;
237         }
238     }
239 
240     return NULL;
241 }
242 
243 void drive_check_orphaned(void)
244 {
245     BlockBackend *blk;
246     DriveInfo *dinfo;
247     Location loc;
248     bool orphans = false;
249 
250     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
251         dinfo = blk_legacy_dinfo(blk);
252         if (!blk_get_attached_dev(blk) && !dinfo->is_default &&
253             dinfo->type != IF_NONE) {
254             loc_push_none(&loc);
255             qemu_opts_loc_restore(dinfo->opts);
256             error_report("machine type does not support"
257                          " if=%s,bus=%d,unit=%d",
258                          if_name[dinfo->type], dinfo->bus, dinfo->unit);
259             loc_pop(&loc);
260             orphans = true;
261         }
262     }
263 
264     if (orphans) {
265         exit(1);
266     }
267 }
268 
269 DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
270 {
271     return drive_get(type,
272                      drive_index_to_bus_id(type, index),
273                      drive_index_to_unit_id(type, index));
274 }
275 
276 int drive_get_max_bus(BlockInterfaceType type)
277 {
278     int max_bus;
279     BlockBackend *blk;
280     DriveInfo *dinfo;
281 
282     max_bus = -1;
283     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
284         dinfo = blk_legacy_dinfo(blk);
285         if (dinfo && dinfo->type == type && dinfo->bus > max_bus) {
286             max_bus = dinfo->bus;
287         }
288     }
289     return max_bus;
290 }
291 
292 /* Get a block device.  This should only be used for single-drive devices
293    (e.g. SD/Floppy/MTD).  Multi-disk devices (scsi/ide) should use the
294    appropriate bus.  */
295 DriveInfo *drive_get_next(BlockInterfaceType type)
296 {
297     static int next_block_unit[IF_COUNT];
298 
299     return drive_get(type, 0, next_block_unit[type]++);
300 }
301 
302 static void bdrv_format_print(void *opaque, const char *name)
303 {
304     error_printf(" %s", name);
305 }
306 
307 typedef struct {
308     QEMUBH *bh;
309     BlockDriverState *bs;
310 } BDRVPutRefBH;
311 
312 static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
313 {
314     if (!strcmp(buf, "ignore")) {
315         return BLOCKDEV_ON_ERROR_IGNORE;
316     } else if (!is_read && !strcmp(buf, "enospc")) {
317         return BLOCKDEV_ON_ERROR_ENOSPC;
318     } else if (!strcmp(buf, "stop")) {
319         return BLOCKDEV_ON_ERROR_STOP;
320     } else if (!strcmp(buf, "report")) {
321         return BLOCKDEV_ON_ERROR_REPORT;
322     } else {
323         error_setg(errp, "'%s' invalid %s error action",
324                    buf, is_read ? "read" : "write");
325         return -1;
326     }
327 }
328 
329 static bool parse_stats_intervals(BlockAcctStats *stats, QList *intervals,
330                                   Error **errp)
331 {
332     const QListEntry *entry;
333     for (entry = qlist_first(intervals); entry; entry = qlist_next(entry)) {
334         switch (qobject_type(entry->value)) {
335 
336         case QTYPE_QSTRING: {
337             unsigned long long length;
338             const char *str = qstring_get_str(qobject_to(QString,
339                                                          entry->value));
340             if (parse_uint_full(str, &length, 10) == 0 &&
341                 length > 0 && length <= UINT_MAX) {
342                 block_acct_add_interval(stats, (unsigned) length);
343             } else {
344                 error_setg(errp, "Invalid interval length: %s", str);
345                 return false;
346             }
347             break;
348         }
349 
350         case QTYPE_QNUM: {
351             int64_t length = qnum_get_int(qobject_to(QNum, entry->value));
352 
353             if (length > 0 && length <= UINT_MAX) {
354                 block_acct_add_interval(stats, (unsigned) length);
355             } else {
356                 error_setg(errp, "Invalid interval length: %" PRId64, length);
357                 return false;
358             }
359             break;
360         }
361 
362         default:
363             error_setg(errp, "The specification of stats-intervals is invalid");
364             return false;
365         }
366     }
367     return true;
368 }
369 
370 typedef enum { MEDIA_DISK, MEDIA_CDROM } DriveMediaType;
371 
372 /* All parameters but @opts are optional and may be set to NULL. */
373 static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
374     const char **throttling_group, ThrottleConfig *throttle_cfg,
375     BlockdevDetectZeroesOptions *detect_zeroes, Error **errp)
376 {
377     Error *local_error = NULL;
378     const char *aio;
379 
380     if (bdrv_flags) {
381         if (qemu_opt_get_bool(opts, "copy-on-read", false)) {
382             *bdrv_flags |= BDRV_O_COPY_ON_READ;
383         }
384 
385         if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
386             if (!strcmp(aio, "native")) {
387                 *bdrv_flags |= BDRV_O_NATIVE_AIO;
388             } else if (!strcmp(aio, "threads")) {
389                 /* this is the default */
390             } else {
391                error_setg(errp, "invalid aio option");
392                return;
393             }
394         }
395     }
396 
397     /* disk I/O throttling */
398     if (throttling_group) {
399         *throttling_group = qemu_opt_get(opts, "throttling.group");
400     }
401 
402     if (throttle_cfg) {
403         throttle_config_init(throttle_cfg);
404         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg =
405             qemu_opt_get_number(opts, "throttling.bps-total", 0);
406         throttle_cfg->buckets[THROTTLE_BPS_READ].avg  =
407             qemu_opt_get_number(opts, "throttling.bps-read", 0);
408         throttle_cfg->buckets[THROTTLE_BPS_WRITE].avg =
409             qemu_opt_get_number(opts, "throttling.bps-write", 0);
410         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].avg =
411             qemu_opt_get_number(opts, "throttling.iops-total", 0);
412         throttle_cfg->buckets[THROTTLE_OPS_READ].avg =
413             qemu_opt_get_number(opts, "throttling.iops-read", 0);
414         throttle_cfg->buckets[THROTTLE_OPS_WRITE].avg =
415             qemu_opt_get_number(opts, "throttling.iops-write", 0);
416 
417         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].max =
418             qemu_opt_get_number(opts, "throttling.bps-total-max", 0);
419         throttle_cfg->buckets[THROTTLE_BPS_READ].max  =
420             qemu_opt_get_number(opts, "throttling.bps-read-max", 0);
421         throttle_cfg->buckets[THROTTLE_BPS_WRITE].max =
422             qemu_opt_get_number(opts, "throttling.bps-write-max", 0);
423         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].max =
424             qemu_opt_get_number(opts, "throttling.iops-total-max", 0);
425         throttle_cfg->buckets[THROTTLE_OPS_READ].max =
426             qemu_opt_get_number(opts, "throttling.iops-read-max", 0);
427         throttle_cfg->buckets[THROTTLE_OPS_WRITE].max =
428             qemu_opt_get_number(opts, "throttling.iops-write-max", 0);
429 
430         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
431             qemu_opt_get_number(opts, "throttling.bps-total-max-length", 1);
432         throttle_cfg->buckets[THROTTLE_BPS_READ].burst_length  =
433             qemu_opt_get_number(opts, "throttling.bps-read-max-length", 1);
434         throttle_cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
435             qemu_opt_get_number(opts, "throttling.bps-write-max-length", 1);
436         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
437             qemu_opt_get_number(opts, "throttling.iops-total-max-length", 1);
438         throttle_cfg->buckets[THROTTLE_OPS_READ].burst_length =
439             qemu_opt_get_number(opts, "throttling.iops-read-max-length", 1);
440         throttle_cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
441             qemu_opt_get_number(opts, "throttling.iops-write-max-length", 1);
442 
443         throttle_cfg->op_size =
444             qemu_opt_get_number(opts, "throttling.iops-size", 0);
445 
446         if (!throttle_is_valid(throttle_cfg, errp)) {
447             return;
448         }
449     }
450 
451     if (detect_zeroes) {
452         *detect_zeroes =
453             qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
454                             qemu_opt_get(opts, "detect-zeroes"),
455                             BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
456                             &local_error);
457         if (local_error) {
458             error_propagate(errp, local_error);
459             return;
460         }
461     }
462 }
463 
464 /* Takes the ownership of bs_opts */
465 static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
466                                    Error **errp)
467 {
468     const char *buf;
469     int bdrv_flags = 0;
470     int on_read_error, on_write_error;
471     bool account_invalid, account_failed;
472     bool writethrough, read_only;
473     BlockBackend *blk;
474     BlockDriverState *bs;
475     ThrottleConfig cfg;
476     int snapshot = 0;
477     Error *error = NULL;
478     QemuOpts *opts;
479     QDict *interval_dict = NULL;
480     QList *interval_list = NULL;
481     const char *id;
482     BlockdevDetectZeroesOptions detect_zeroes =
483         BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
484     const char *throttling_group = NULL;
485 
486     /* Check common options by copying from bs_opts to opts, all other options
487      * stay in bs_opts for processing by bdrv_open(). */
488     id = qdict_get_try_str(bs_opts, "id");
489     opts = qemu_opts_create(&qemu_common_drive_opts, id, 1, &error);
490     if (error) {
491         error_propagate(errp, error);
492         goto err_no_opts;
493     }
494 
495     qemu_opts_absorb_qdict(opts, bs_opts, &error);
496     if (error) {
497         error_propagate(errp, error);
498         goto early_err;
499     }
500 
501     if (id) {
502         qdict_del(bs_opts, "id");
503     }
504 
505     /* extract parameters */
506     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
507 
508     account_invalid = qemu_opt_get_bool(opts, "stats-account-invalid", true);
509     account_failed = qemu_opt_get_bool(opts, "stats-account-failed", true);
510 
511     writethrough = !qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, true);
512 
513     id = qemu_opts_id(opts);
514 
515     qdict_extract_subqdict(bs_opts, &interval_dict, "stats-intervals.");
516     qdict_array_split(interval_dict, &interval_list);
517 
518     if (qdict_size(interval_dict) != 0) {
519         error_setg(errp, "Invalid option stats-intervals.%s",
520                    qdict_first(interval_dict)->key);
521         goto early_err;
522     }
523 
524     extract_common_blockdev_options(opts, &bdrv_flags, &throttling_group, &cfg,
525                                     &detect_zeroes, &error);
526     if (error) {
527         error_propagate(errp, error);
528         goto early_err;
529     }
530 
531     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
532         if (is_help_option(buf)) {
533             error_printf("Supported formats:");
534             bdrv_iterate_format(bdrv_format_print, NULL);
535             error_printf("\n");
536             goto early_err;
537         }
538 
539         if (qdict_haskey(bs_opts, "driver")) {
540             error_setg(errp, "Cannot specify both 'driver' and 'format'");
541             goto early_err;
542         }
543         qdict_put_str(bs_opts, "driver", buf);
544     }
545 
546     on_write_error = BLOCKDEV_ON_ERROR_ENOSPC;
547     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
548         on_write_error = parse_block_error_action(buf, 0, &error);
549         if (error) {
550             error_propagate(errp, error);
551             goto early_err;
552         }
553     }
554 
555     on_read_error = BLOCKDEV_ON_ERROR_REPORT;
556     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
557         on_read_error = parse_block_error_action(buf, 1, &error);
558         if (error) {
559             error_propagate(errp, error);
560             goto early_err;
561         }
562     }
563 
564     if (snapshot) {
565         bdrv_flags |= BDRV_O_SNAPSHOT;
566     }
567 
568     read_only = qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false);
569 
570     /* init */
571     if ((!file || !*file) && !qdict_size(bs_opts)) {
572         BlockBackendRootState *blk_rs;
573 
574         blk = blk_new(0, BLK_PERM_ALL);
575         blk_rs = blk_get_root_state(blk);
576         blk_rs->open_flags    = bdrv_flags;
577         blk_rs->read_only     = read_only;
578         blk_rs->detect_zeroes = detect_zeroes;
579 
580         qobject_unref(bs_opts);
581     } else {
582         if (file && !*file) {
583             file = NULL;
584         }
585 
586         /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
587          * with other callers) rather than what we want as the real defaults.
588          * Apply the defaults here instead. */
589         qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
590         qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
591         qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY,
592                               read_only ? "on" : "off");
593         assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0);
594 
595         if (runstate_check(RUN_STATE_INMIGRATE)) {
596             bdrv_flags |= BDRV_O_INACTIVE;
597         }
598 
599         blk = blk_new_open(file, NULL, bs_opts, bdrv_flags, errp);
600         if (!blk) {
601             goto err_no_bs_opts;
602         }
603         bs = blk_bs(blk);
604 
605         bs->detect_zeroes = detect_zeroes;
606 
607         block_acct_setup(blk_get_stats(blk), account_invalid, account_failed);
608 
609         if (!parse_stats_intervals(blk_get_stats(blk), interval_list, errp)) {
610             blk_unref(blk);
611             blk = NULL;
612             goto err_no_bs_opts;
613         }
614     }
615 
616     /* disk I/O throttling */
617     if (throttle_enabled(&cfg)) {
618         if (!throttling_group) {
619             throttling_group = id;
620         }
621         blk_io_limits_enable(blk, throttling_group);
622         blk_set_io_limits(blk, &cfg);
623     }
624 
625     blk_set_enable_write_cache(blk, !writethrough);
626     blk_set_on_error(blk, on_read_error, on_write_error);
627 
628     if (!monitor_add_blk(blk, id, errp)) {
629         blk_unref(blk);
630         blk = NULL;
631         goto err_no_bs_opts;
632     }
633 
634 err_no_bs_opts:
635     qemu_opts_del(opts);
636     qobject_unref(interval_dict);
637     qobject_unref(interval_list);
638     return blk;
639 
640 early_err:
641     qemu_opts_del(opts);
642     qobject_unref(interval_dict);
643     qobject_unref(interval_list);
644 err_no_opts:
645     qobject_unref(bs_opts);
646     return NULL;
647 }
648 
649 /* Takes the ownership of bs_opts */
650 static BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)
651 {
652     int bdrv_flags = 0;
653 
654     /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
655      * with other callers) rather than what we want as the real defaults.
656      * Apply the defaults here instead. */
657     qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
658     qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
659     qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, "off");
660 
661     if (runstate_check(RUN_STATE_INMIGRATE)) {
662         bdrv_flags |= BDRV_O_INACTIVE;
663     }
664 
665     return bdrv_open(NULL, NULL, bs_opts, bdrv_flags, errp);
666 }
667 
668 void blockdev_close_all_bdrv_states(void)
669 {
670     BlockDriverState *bs, *next_bs;
671 
672     QTAILQ_FOREACH_SAFE(bs, &monitor_bdrv_states, monitor_list, next_bs) {
673         AioContext *ctx = bdrv_get_aio_context(bs);
674 
675         aio_context_acquire(ctx);
676         bdrv_unref(bs);
677         aio_context_release(ctx);
678     }
679 }
680 
681 /* Iterates over the list of monitor-owned BlockDriverStates */
682 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs)
683 {
684     return bs ? QTAILQ_NEXT(bs, monitor_list)
685               : QTAILQ_FIRST(&monitor_bdrv_states);
686 }
687 
688 static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
689                             Error **errp)
690 {
691     const char *value;
692 
693     value = qemu_opt_get(opts, from);
694     if (value) {
695         if (qemu_opt_find(opts, to)) {
696             error_setg(errp, "'%s' and its alias '%s' can't be used at the "
697                        "same time", to, from);
698             return;
699         }
700     }
701 
702     /* rename all items in opts */
703     while ((value = qemu_opt_get(opts, from))) {
704         qemu_opt_set(opts, to, value, &error_abort);
705         qemu_opt_unset(opts, from);
706     }
707 }
708 
709 QemuOptsList qemu_legacy_drive_opts = {
710     .name = "drive",
711     .head = QTAILQ_HEAD_INITIALIZER(qemu_legacy_drive_opts.head),
712     .desc = {
713         {
714             .name = "bus",
715             .type = QEMU_OPT_NUMBER,
716             .help = "bus number",
717         },{
718             .name = "unit",
719             .type = QEMU_OPT_NUMBER,
720             .help = "unit number (i.e. lun for scsi)",
721         },{
722             .name = "index",
723             .type = QEMU_OPT_NUMBER,
724             .help = "index number",
725         },{
726             .name = "media",
727             .type = QEMU_OPT_STRING,
728             .help = "media type (disk, cdrom)",
729         },{
730             .name = "if",
731             .type = QEMU_OPT_STRING,
732             .help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
733         },{
734             .name = "cyls",
735             .type = QEMU_OPT_NUMBER,
736             .help = "number of cylinders (ide disk geometry)",
737         },{
738             .name = "heads",
739             .type = QEMU_OPT_NUMBER,
740             .help = "number of heads (ide disk geometry)",
741         },{
742             .name = "secs",
743             .type = QEMU_OPT_NUMBER,
744             .help = "number of sectors (ide disk geometry)",
745         },{
746             .name = "trans",
747             .type = QEMU_OPT_STRING,
748             .help = "chs translation (auto, lba, none)",
749         },{
750             .name = "addr",
751             .type = QEMU_OPT_STRING,
752             .help = "pci address (virtio only)",
753         },{
754             .name = "serial",
755             .type = QEMU_OPT_STRING,
756             .help = "disk serial number",
757         },{
758             .name = "file",
759             .type = QEMU_OPT_STRING,
760             .help = "file name",
761         },
762 
763         /* Options that are passed on, but have special semantics with -drive */
764         {
765             .name = BDRV_OPT_READ_ONLY,
766             .type = QEMU_OPT_BOOL,
767             .help = "open drive file as read-only",
768         },{
769             .name = "rerror",
770             .type = QEMU_OPT_STRING,
771             .help = "read error action",
772         },{
773             .name = "werror",
774             .type = QEMU_OPT_STRING,
775             .help = "write error action",
776         },{
777             .name = "copy-on-read",
778             .type = QEMU_OPT_BOOL,
779             .help = "copy read data from backing file into image file",
780         },
781 
782         { /* end of list */ }
783     },
784 };
785 
786 DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type)
787 {
788     const char *value;
789     BlockBackend *blk;
790     DriveInfo *dinfo = NULL;
791     QDict *bs_opts;
792     QemuOpts *legacy_opts;
793     DriveMediaType media = MEDIA_DISK;
794     BlockInterfaceType type;
795     int cyls, heads, secs, translation;
796     int max_devs, bus_id, unit_id, index;
797     const char *devaddr;
798     const char *werror, *rerror;
799     bool read_only = false;
800     bool copy_on_read;
801     const char *serial;
802     const char *filename;
803     Error *local_err = NULL;
804     int i;
805     const char *deprecated[] = {
806         "serial", "trans", "secs", "heads", "cyls", "addr"
807     };
808 
809     /* Change legacy command line options into QMP ones */
810     static const struct {
811         const char *from;
812         const char *to;
813     } opt_renames[] = {
814         { "iops",           "throttling.iops-total" },
815         { "iops_rd",        "throttling.iops-read" },
816         { "iops_wr",        "throttling.iops-write" },
817 
818         { "bps",            "throttling.bps-total" },
819         { "bps_rd",         "throttling.bps-read" },
820         { "bps_wr",         "throttling.bps-write" },
821 
822         { "iops_max",       "throttling.iops-total-max" },
823         { "iops_rd_max",    "throttling.iops-read-max" },
824         { "iops_wr_max",    "throttling.iops-write-max" },
825 
826         { "bps_max",        "throttling.bps-total-max" },
827         { "bps_rd_max",     "throttling.bps-read-max" },
828         { "bps_wr_max",     "throttling.bps-write-max" },
829 
830         { "iops_size",      "throttling.iops-size" },
831 
832         { "group",          "throttling.group" },
833 
834         { "readonly",       BDRV_OPT_READ_ONLY },
835     };
836 
837     for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
838         qemu_opt_rename(all_opts, opt_renames[i].from, opt_renames[i].to,
839                         &local_err);
840         if (local_err) {
841             error_report_err(local_err);
842             return NULL;
843         }
844     }
845 
846     value = qemu_opt_get(all_opts, "cache");
847     if (value) {
848         int flags = 0;
849         bool writethrough;
850 
851         if (bdrv_parse_cache_mode(value, &flags, &writethrough) != 0) {
852             error_report("invalid cache option");
853             return NULL;
854         }
855 
856         /* Specific options take precedence */
857         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_WB)) {
858             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_WB,
859                               !writethrough, &error_abort);
860         }
861         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_DIRECT)) {
862             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_DIRECT,
863                               !!(flags & BDRV_O_NOCACHE), &error_abort);
864         }
865         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_NO_FLUSH)) {
866             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_NO_FLUSH,
867                               !!(flags & BDRV_O_NO_FLUSH), &error_abort);
868         }
869         qemu_opt_unset(all_opts, "cache");
870     }
871 
872     /* Get a QDict for processing the options */
873     bs_opts = qdict_new();
874     qemu_opts_to_qdict(all_opts, bs_opts);
875 
876     legacy_opts = qemu_opts_create(&qemu_legacy_drive_opts, NULL, 0,
877                                    &error_abort);
878     qemu_opts_absorb_qdict(legacy_opts, bs_opts, &local_err);
879     if (local_err) {
880         error_report_err(local_err);
881         goto fail;
882     }
883 
884     /* Other deprecated options */
885     if (!qtest_enabled()) {
886         for (i = 0; i < ARRAY_SIZE(deprecated); i++) {
887             if (qemu_opt_get(legacy_opts, deprecated[i]) != NULL) {
888                 error_report("'%s' is deprecated, please use the corresponding "
889                              "option of '-device' instead", deprecated[i]);
890             }
891         }
892     }
893 
894     /* Media type */
895     value = qemu_opt_get(legacy_opts, "media");
896     if (value) {
897         if (!strcmp(value, "disk")) {
898             media = MEDIA_DISK;
899         } else if (!strcmp(value, "cdrom")) {
900             media = MEDIA_CDROM;
901             read_only = true;
902         } else {
903             error_report("'%s' invalid media", value);
904             goto fail;
905         }
906     }
907 
908     /* copy-on-read is disabled with a warning for read-only devices */
909     read_only |= qemu_opt_get_bool(legacy_opts, BDRV_OPT_READ_ONLY, false);
910     copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false);
911 
912     if (read_only && copy_on_read) {
913         warn_report("disabling copy-on-read on read-only drive");
914         copy_on_read = false;
915     }
916 
917     qdict_put_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off");
918     qdict_put_str(bs_opts, "copy-on-read", copy_on_read ? "on" : "off");
919 
920     /* Controller type */
921     value = qemu_opt_get(legacy_opts, "if");
922     if (value) {
923         for (type = 0;
924              type < IF_COUNT && strcmp(value, if_name[type]);
925              type++) {
926         }
927         if (type == IF_COUNT) {
928             error_report("unsupported bus type '%s'", value);
929             goto fail;
930         }
931     } else {
932         type = block_default_type;
933     }
934 
935     /* Geometry */
936     cyls  = qemu_opt_get_number(legacy_opts, "cyls", 0);
937     heads = qemu_opt_get_number(legacy_opts, "heads", 0);
938     secs  = qemu_opt_get_number(legacy_opts, "secs", 0);
939 
940     if (cyls || heads || secs) {
941         if (cyls < 1) {
942             error_report("invalid physical cyls number");
943             goto fail;
944         }
945         if (heads < 1) {
946             error_report("invalid physical heads number");
947             goto fail;
948         }
949         if (secs < 1) {
950             error_report("invalid physical secs number");
951             goto fail;
952         }
953     }
954 
955     translation = BIOS_ATA_TRANSLATION_AUTO;
956     value = qemu_opt_get(legacy_opts, "trans");
957     if (value != NULL) {
958         if (!cyls) {
959             error_report("'%s' trans must be used with cyls, heads and secs",
960                          value);
961             goto fail;
962         }
963         if (!strcmp(value, "none")) {
964             translation = BIOS_ATA_TRANSLATION_NONE;
965         } else if (!strcmp(value, "lba")) {
966             translation = BIOS_ATA_TRANSLATION_LBA;
967         } else if (!strcmp(value, "large")) {
968             translation = BIOS_ATA_TRANSLATION_LARGE;
969         } else if (!strcmp(value, "rechs")) {
970             translation = BIOS_ATA_TRANSLATION_RECHS;
971         } else if (!strcmp(value, "auto")) {
972             translation = BIOS_ATA_TRANSLATION_AUTO;
973         } else {
974             error_report("'%s' invalid translation type", value);
975             goto fail;
976         }
977     }
978 
979     if (media == MEDIA_CDROM) {
980         if (cyls || secs || heads) {
981             error_report("CHS can't be set with media=cdrom");
982             goto fail;
983         }
984     }
985 
986     /* Device address specified by bus/unit or index.
987      * If none was specified, try to find the first free one. */
988     bus_id  = qemu_opt_get_number(legacy_opts, "bus", 0);
989     unit_id = qemu_opt_get_number(legacy_opts, "unit", -1);
990     index   = qemu_opt_get_number(legacy_opts, "index", -1);
991 
992     max_devs = if_max_devs[type];
993 
994     if (index != -1) {
995         if (bus_id != 0 || unit_id != -1) {
996             error_report("index cannot be used with bus and unit");
997             goto fail;
998         }
999         bus_id = drive_index_to_bus_id(type, index);
1000         unit_id = drive_index_to_unit_id(type, index);
1001     }
1002 
1003     if (unit_id == -1) {
1004        unit_id = 0;
1005        while (drive_get(type, bus_id, unit_id) != NULL) {
1006            unit_id++;
1007            if (max_devs && unit_id >= max_devs) {
1008                unit_id -= max_devs;
1009                bus_id++;
1010            }
1011        }
1012     }
1013 
1014     if (max_devs && unit_id >= max_devs) {
1015         error_report("unit %d too big (max is %d)", unit_id, max_devs - 1);
1016         goto fail;
1017     }
1018 
1019     if (drive_get(type, bus_id, unit_id) != NULL) {
1020         error_report("drive with bus=%d, unit=%d (index=%d) exists",
1021                      bus_id, unit_id, index);
1022         goto fail;
1023     }
1024 
1025     /* Serial number */
1026     serial = qemu_opt_get(legacy_opts, "serial");
1027 
1028     /* no id supplied -> create one */
1029     if (qemu_opts_id(all_opts) == NULL) {
1030         char *new_id;
1031         const char *mediastr = "";
1032         if (type == IF_IDE || type == IF_SCSI) {
1033             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
1034         }
1035         if (max_devs) {
1036             new_id = g_strdup_printf("%s%i%s%i", if_name[type], bus_id,
1037                                      mediastr, unit_id);
1038         } else {
1039             new_id = g_strdup_printf("%s%s%i", if_name[type],
1040                                      mediastr, unit_id);
1041         }
1042         qdict_put_str(bs_opts, "id", new_id);
1043         g_free(new_id);
1044     }
1045 
1046     /* Add virtio block device */
1047     devaddr = qemu_opt_get(legacy_opts, "addr");
1048     if (devaddr && type != IF_VIRTIO) {
1049         error_report("addr is not supported by this bus type");
1050         goto fail;
1051     }
1052 
1053     if (type == IF_VIRTIO) {
1054         QemuOpts *devopts;
1055         devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
1056                                    &error_abort);
1057         if (arch_type == QEMU_ARCH_S390X) {
1058             qemu_opt_set(devopts, "driver", "virtio-blk-ccw", &error_abort);
1059         } else {
1060             qemu_opt_set(devopts, "driver", "virtio-blk-pci", &error_abort);
1061         }
1062         qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
1063                      &error_abort);
1064         if (devaddr) {
1065             qemu_opt_set(devopts, "addr", devaddr, &error_abort);
1066         }
1067     }
1068 
1069     filename = qemu_opt_get(legacy_opts, "file");
1070 
1071     /* Check werror/rerror compatibility with if=... */
1072     werror = qemu_opt_get(legacy_opts, "werror");
1073     if (werror != NULL) {
1074         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO &&
1075             type != IF_NONE) {
1076             error_report("werror is not supported by this bus type");
1077             goto fail;
1078         }
1079         qdict_put_str(bs_opts, "werror", werror);
1080     }
1081 
1082     rerror = qemu_opt_get(legacy_opts, "rerror");
1083     if (rerror != NULL) {
1084         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI &&
1085             type != IF_NONE) {
1086             error_report("rerror is not supported by this bus type");
1087             goto fail;
1088         }
1089         qdict_put_str(bs_opts, "rerror", rerror);
1090     }
1091 
1092     /* Actual block device init: Functionality shared with blockdev-add */
1093     blk = blockdev_init(filename, bs_opts, &local_err);
1094     bs_opts = NULL;
1095     if (!blk) {
1096         if (local_err) {
1097             error_report_err(local_err);
1098         }
1099         goto fail;
1100     } else {
1101         assert(!local_err);
1102     }
1103 
1104     /* Create legacy DriveInfo */
1105     dinfo = g_malloc0(sizeof(*dinfo));
1106     dinfo->opts = all_opts;
1107 
1108     dinfo->cyls = cyls;
1109     dinfo->heads = heads;
1110     dinfo->secs = secs;
1111     dinfo->trans = translation;
1112 
1113     dinfo->type = type;
1114     dinfo->bus = bus_id;
1115     dinfo->unit = unit_id;
1116     dinfo->devaddr = devaddr;
1117     dinfo->serial = g_strdup(serial);
1118 
1119     blk_set_legacy_dinfo(blk, dinfo);
1120 
1121     switch(type) {
1122     case IF_IDE:
1123     case IF_SCSI:
1124     case IF_XEN:
1125     case IF_NONE:
1126         dinfo->media_cd = media == MEDIA_CDROM;
1127         break;
1128     default:
1129         break;
1130     }
1131 
1132 fail:
1133     qemu_opts_del(legacy_opts);
1134     qobject_unref(bs_opts);
1135     return dinfo;
1136 }
1137 
1138 static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp)
1139 {
1140     BlockDriverState *bs;
1141 
1142     bs = bdrv_lookup_bs(name, name, errp);
1143     if (bs == NULL) {
1144         return NULL;
1145     }
1146 
1147     if (!bdrv_is_root_node(bs)) {
1148         error_setg(errp, "Need a root block node");
1149         return NULL;
1150     }
1151 
1152     if (!bdrv_is_inserted(bs)) {
1153         error_setg(errp, "Device has no medium");
1154         return NULL;
1155     }
1156 
1157     return bs;
1158 }
1159 
1160 static BlockBackend *qmp_get_blk(const char *blk_name, const char *qdev_id,
1161                                  Error **errp)
1162 {
1163     BlockBackend *blk;
1164 
1165     if (!blk_name == !qdev_id) {
1166         error_setg(errp, "Need exactly one of 'device' and 'id'");
1167         return NULL;
1168     }
1169 
1170     if (qdev_id) {
1171         blk = blk_by_qdev_id(qdev_id, errp);
1172     } else {
1173         blk = blk_by_name(blk_name);
1174         if (blk == NULL) {
1175             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1176                       "Device '%s' not found", blk_name);
1177         }
1178     }
1179 
1180     return blk;
1181 }
1182 
1183 void hmp_commit(Monitor *mon, const QDict *qdict)
1184 {
1185     const char *device = qdict_get_str(qdict, "device");
1186     BlockBackend *blk;
1187     int ret;
1188 
1189     if (!strcmp(device, "all")) {
1190         ret = blk_commit_all();
1191     } else {
1192         BlockDriverState *bs;
1193         AioContext *aio_context;
1194 
1195         blk = blk_by_name(device);
1196         if (!blk) {
1197             monitor_printf(mon, "Device '%s' not found\n", device);
1198             return;
1199         }
1200         if (!blk_is_available(blk)) {
1201             monitor_printf(mon, "Device '%s' has no medium\n", device);
1202             return;
1203         }
1204 
1205         bs = blk_bs(blk);
1206         aio_context = bdrv_get_aio_context(bs);
1207         aio_context_acquire(aio_context);
1208 
1209         ret = bdrv_commit(bs);
1210 
1211         aio_context_release(aio_context);
1212     }
1213     if (ret < 0) {
1214         monitor_printf(mon, "'commit' error for '%s': %s\n", device,
1215                        strerror(-ret));
1216     }
1217 }
1218 
1219 static void blockdev_do_action(TransactionAction *action, Error **errp)
1220 {
1221     TransactionActionList list;
1222 
1223     list.value = action;
1224     list.next = NULL;
1225     qmp_transaction(&list, false, NULL, errp);
1226 }
1227 
1228 void qmp_blockdev_snapshot_sync(bool has_device, const char *device,
1229                                 bool has_node_name, const char *node_name,
1230                                 const char *snapshot_file,
1231                                 bool has_snapshot_node_name,
1232                                 const char *snapshot_node_name,
1233                                 bool has_format, const char *format,
1234                                 bool has_mode, NewImageMode mode, Error **errp)
1235 {
1236     BlockdevSnapshotSync snapshot = {
1237         .has_device = has_device,
1238         .device = (char *) device,
1239         .has_node_name = has_node_name,
1240         .node_name = (char *) node_name,
1241         .snapshot_file = (char *) snapshot_file,
1242         .has_snapshot_node_name = has_snapshot_node_name,
1243         .snapshot_node_name = (char *) snapshot_node_name,
1244         .has_format = has_format,
1245         .format = (char *) format,
1246         .has_mode = has_mode,
1247         .mode = mode,
1248     };
1249     TransactionAction action = {
1250         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
1251         .u.blockdev_snapshot_sync.data = &snapshot,
1252     };
1253     blockdev_do_action(&action, errp);
1254 }
1255 
1256 void qmp_blockdev_snapshot(const char *node, const char *overlay,
1257                            Error **errp)
1258 {
1259     BlockdevSnapshot snapshot_data = {
1260         .node = (char *) node,
1261         .overlay = (char *) overlay
1262     };
1263     TransactionAction action = {
1264         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT,
1265         .u.blockdev_snapshot.data = &snapshot_data,
1266     };
1267     blockdev_do_action(&action, errp);
1268 }
1269 
1270 void qmp_blockdev_snapshot_internal_sync(const char *device,
1271                                          const char *name,
1272                                          Error **errp)
1273 {
1274     BlockdevSnapshotInternal snapshot = {
1275         .device = (char *) device,
1276         .name = (char *) name
1277     };
1278     TransactionAction action = {
1279         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
1280         .u.blockdev_snapshot_internal_sync.data = &snapshot,
1281     };
1282     blockdev_do_action(&action, errp);
1283 }
1284 
1285 SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
1286                                                          bool has_id,
1287                                                          const char *id,
1288                                                          bool has_name,
1289                                                          const char *name,
1290                                                          Error **errp)
1291 {
1292     BlockDriverState *bs;
1293     AioContext *aio_context;
1294     QEMUSnapshotInfo sn;
1295     Error *local_err = NULL;
1296     SnapshotInfo *info = NULL;
1297     int ret;
1298 
1299     bs = qmp_get_root_bs(device, errp);
1300     if (!bs) {
1301         return NULL;
1302     }
1303     aio_context = bdrv_get_aio_context(bs);
1304     aio_context_acquire(aio_context);
1305 
1306     if (!has_id) {
1307         id = NULL;
1308     }
1309 
1310     if (!has_name) {
1311         name = NULL;
1312     }
1313 
1314     if (!id && !name) {
1315         error_setg(errp, "Name or id must be provided");
1316         goto out_aio_context;
1317     }
1318 
1319     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, errp)) {
1320         goto out_aio_context;
1321     }
1322 
1323     ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
1324     if (local_err) {
1325         error_propagate(errp, local_err);
1326         goto out_aio_context;
1327     }
1328     if (!ret) {
1329         error_setg(errp,
1330                    "Snapshot with id '%s' and name '%s' does not exist on "
1331                    "device '%s'",
1332                    STR_OR_NULL(id), STR_OR_NULL(name), device);
1333         goto out_aio_context;
1334     }
1335 
1336     bdrv_snapshot_delete(bs, id, name, &local_err);
1337     if (local_err) {
1338         error_propagate(errp, local_err);
1339         goto out_aio_context;
1340     }
1341 
1342     aio_context_release(aio_context);
1343 
1344     info = g_new0(SnapshotInfo, 1);
1345     info->id = g_strdup(sn.id_str);
1346     info->name = g_strdup(sn.name);
1347     info->date_nsec = sn.date_nsec;
1348     info->date_sec = sn.date_sec;
1349     info->vm_state_size = sn.vm_state_size;
1350     info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
1351     info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
1352 
1353     return info;
1354 
1355 out_aio_context:
1356     aio_context_release(aio_context);
1357     return NULL;
1358 }
1359 
1360 /**
1361  * block_dirty_bitmap_lookup:
1362  * Return a dirty bitmap (if present), after validating
1363  * the node reference and bitmap names.
1364  *
1365  * @node: The name of the BDS node to search for bitmaps
1366  * @name: The name of the bitmap to search for
1367  * @pbs: Output pointer for BDS lookup, if desired. Can be NULL.
1368  * @paio: Output pointer for aio_context acquisition, if desired. Can be NULL.
1369  * @errp: Output pointer for error information. Can be NULL.
1370  *
1371  * @return: A bitmap object on success, or NULL on failure.
1372  */
1373 static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
1374                                                   const char *name,
1375                                                   BlockDriverState **pbs,
1376                                                   Error **errp)
1377 {
1378     BlockDriverState *bs;
1379     BdrvDirtyBitmap *bitmap;
1380 
1381     if (!node) {
1382         error_setg(errp, "Node cannot be NULL");
1383         return NULL;
1384     }
1385     if (!name) {
1386         error_setg(errp, "Bitmap name cannot be NULL");
1387         return NULL;
1388     }
1389     bs = bdrv_lookup_bs(node, node, NULL);
1390     if (!bs) {
1391         error_setg(errp, "Node '%s' not found", node);
1392         return NULL;
1393     }
1394 
1395     bitmap = bdrv_find_dirty_bitmap(bs, name);
1396     if (!bitmap) {
1397         error_setg(errp, "Dirty bitmap '%s' not found", name);
1398         return NULL;
1399     }
1400 
1401     if (pbs) {
1402         *pbs = bs;
1403     }
1404 
1405     return bitmap;
1406 }
1407 
1408 /* New and old BlockDriverState structs for atomic group operations */
1409 
1410 typedef struct BlkActionState BlkActionState;
1411 
1412 /**
1413  * BlkActionOps:
1414  * Table of operations that define an Action.
1415  *
1416  * @instance_size: Size of state struct, in bytes.
1417  * @prepare: Prepare the work, must NOT be NULL.
1418  * @commit: Commit the changes, can be NULL.
1419  * @abort: Abort the changes on fail, can be NULL.
1420  * @clean: Clean up resources after all transaction actions have called
1421  *         commit() or abort(). Can be NULL.
1422  *
1423  * Only prepare() may fail. In a single transaction, only one of commit() or
1424  * abort() will be called. clean() will always be called if it is present.
1425  */
1426 typedef struct BlkActionOps {
1427     size_t instance_size;
1428     void (*prepare)(BlkActionState *common, Error **errp);
1429     void (*commit)(BlkActionState *common);
1430     void (*abort)(BlkActionState *common);
1431     void (*clean)(BlkActionState *common);
1432 } BlkActionOps;
1433 
1434 /**
1435  * BlkActionState:
1436  * Describes one Action's state within a Transaction.
1437  *
1438  * @action: QAPI-defined enum identifying which Action to perform.
1439  * @ops: Table of ActionOps this Action can perform.
1440  * @block_job_txn: Transaction which this action belongs to.
1441  * @entry: List membership for all Actions in this Transaction.
1442  *
1443  * This structure must be arranged as first member in a subclassed type,
1444  * assuming that the compiler will also arrange it to the same offsets as the
1445  * base class.
1446  */
1447 struct BlkActionState {
1448     TransactionAction *action;
1449     const BlkActionOps *ops;
1450     JobTxn *block_job_txn;
1451     TransactionProperties *txn_props;
1452     QSIMPLEQ_ENTRY(BlkActionState) entry;
1453 };
1454 
1455 /* internal snapshot private data */
1456 typedef struct InternalSnapshotState {
1457     BlkActionState common;
1458     BlockDriverState *bs;
1459     QEMUSnapshotInfo sn;
1460     bool created;
1461 } InternalSnapshotState;
1462 
1463 
1464 static int action_check_completion_mode(BlkActionState *s, Error **errp)
1465 {
1466     if (s->txn_props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
1467         error_setg(errp,
1468                    "Action '%s' does not support Transaction property "
1469                    "completion-mode = %s",
1470                    TransactionActionKind_str(s->action->type),
1471                    ActionCompletionMode_str(s->txn_props->completion_mode));
1472         return -1;
1473     }
1474     return 0;
1475 }
1476 
1477 static void internal_snapshot_prepare(BlkActionState *common,
1478                                       Error **errp)
1479 {
1480     Error *local_err = NULL;
1481     const char *device;
1482     const char *name;
1483     BlockDriverState *bs;
1484     QEMUSnapshotInfo old_sn, *sn;
1485     bool ret;
1486     qemu_timeval tv;
1487     BlockdevSnapshotInternal *internal;
1488     InternalSnapshotState *state;
1489     AioContext *aio_context;
1490     int ret1;
1491 
1492     g_assert(common->action->type ==
1493              TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC);
1494     internal = common->action->u.blockdev_snapshot_internal_sync.data;
1495     state = DO_UPCAST(InternalSnapshotState, common, common);
1496 
1497     /* 1. parse input */
1498     device = internal->device;
1499     name = internal->name;
1500 
1501     /* 2. check for validation */
1502     if (action_check_completion_mode(common, errp) < 0) {
1503         return;
1504     }
1505 
1506     bs = qmp_get_root_bs(device, errp);
1507     if (!bs) {
1508         return;
1509     }
1510 
1511     aio_context = bdrv_get_aio_context(bs);
1512     aio_context_acquire(aio_context);
1513 
1514     state->bs = bs;
1515 
1516     /* Paired with .clean() */
1517     bdrv_drained_begin(bs);
1518 
1519     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {
1520         goto out;
1521     }
1522 
1523     if (bdrv_is_read_only(bs)) {
1524         error_setg(errp, "Device '%s' is read only", device);
1525         goto out;
1526     }
1527 
1528     if (!bdrv_can_snapshot(bs)) {
1529         error_setg(errp, "Block format '%s' used by device '%s' "
1530                    "does not support internal snapshots",
1531                    bs->drv->format_name, device);
1532         goto out;
1533     }
1534 
1535     if (!strlen(name)) {
1536         error_setg(errp, "Name is empty");
1537         goto out;
1538     }
1539 
1540     /* check whether a snapshot with name exist */
1541     ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn,
1542                                             &local_err);
1543     if (local_err) {
1544         error_propagate(errp, local_err);
1545         goto out;
1546     } else if (ret) {
1547         error_setg(errp,
1548                    "Snapshot with name '%s' already exists on device '%s'",
1549                    name, device);
1550         goto out;
1551     }
1552 
1553     /* 3. take the snapshot */
1554     sn = &state->sn;
1555     pstrcpy(sn->name, sizeof(sn->name), name);
1556     qemu_gettimeofday(&tv);
1557     sn->date_sec = tv.tv_sec;
1558     sn->date_nsec = tv.tv_usec * 1000;
1559     sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
1560 
1561     ret1 = bdrv_snapshot_create(bs, sn);
1562     if (ret1 < 0) {
1563         error_setg_errno(errp, -ret1,
1564                          "Failed to create snapshot '%s' on device '%s'",
1565                          name, device);
1566         goto out;
1567     }
1568 
1569     /* 4. succeed, mark a snapshot is created */
1570     state->created = true;
1571 
1572 out:
1573     aio_context_release(aio_context);
1574 }
1575 
1576 static void internal_snapshot_abort(BlkActionState *common)
1577 {
1578     InternalSnapshotState *state =
1579                              DO_UPCAST(InternalSnapshotState, common, common);
1580     BlockDriverState *bs = state->bs;
1581     QEMUSnapshotInfo *sn = &state->sn;
1582     AioContext *aio_context;
1583     Error *local_error = NULL;
1584 
1585     if (!state->created) {
1586         return;
1587     }
1588 
1589     aio_context = bdrv_get_aio_context(state->bs);
1590     aio_context_acquire(aio_context);
1591 
1592     if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {
1593         error_reportf_err(local_error,
1594                           "Failed to delete snapshot with id '%s' and "
1595                           "name '%s' on device '%s' in abort: ",
1596                           sn->id_str, sn->name,
1597                           bdrv_get_device_name(bs));
1598     }
1599 
1600     aio_context_release(aio_context);
1601 }
1602 
1603 static void internal_snapshot_clean(BlkActionState *common)
1604 {
1605     InternalSnapshotState *state = DO_UPCAST(InternalSnapshotState,
1606                                              common, common);
1607     AioContext *aio_context;
1608 
1609     if (!state->bs) {
1610         return;
1611     }
1612 
1613     aio_context = bdrv_get_aio_context(state->bs);
1614     aio_context_acquire(aio_context);
1615 
1616     bdrv_drained_end(state->bs);
1617 
1618     aio_context_release(aio_context);
1619 }
1620 
1621 /* external snapshot private data */
1622 typedef struct ExternalSnapshotState {
1623     BlkActionState common;
1624     BlockDriverState *old_bs;
1625     BlockDriverState *new_bs;
1626     bool overlay_appended;
1627 } ExternalSnapshotState;
1628 
1629 static void external_snapshot_prepare(BlkActionState *common,
1630                                       Error **errp)
1631 {
1632     int flags = 0;
1633     QDict *options = NULL;
1634     Error *local_err = NULL;
1635     /* Device and node name of the image to generate the snapshot from */
1636     const char *device;
1637     const char *node_name;
1638     /* Reference to the new image (for 'blockdev-snapshot') */
1639     const char *snapshot_ref;
1640     /* File name of the new image (for 'blockdev-snapshot-sync') */
1641     const char *new_image_file;
1642     ExternalSnapshotState *state =
1643                              DO_UPCAST(ExternalSnapshotState, common, common);
1644     TransactionAction *action = common->action;
1645     AioContext *aio_context;
1646 
1647     /* 'blockdev-snapshot' and 'blockdev-snapshot-sync' have similar
1648      * purpose but a different set of parameters */
1649     switch (action->type) {
1650     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
1651         {
1652             BlockdevSnapshot *s = action->u.blockdev_snapshot.data;
1653             device = s->node;
1654             node_name = s->node;
1655             new_image_file = NULL;
1656             snapshot_ref = s->overlay;
1657         }
1658         break;
1659     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
1660         {
1661             BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1662             device = s->has_device ? s->device : NULL;
1663             node_name = s->has_node_name ? s->node_name : NULL;
1664             new_image_file = s->snapshot_file;
1665             snapshot_ref = NULL;
1666         }
1667         break;
1668     default:
1669         g_assert_not_reached();
1670     }
1671 
1672     /* start processing */
1673     if (action_check_completion_mode(common, errp) < 0) {
1674         return;
1675     }
1676 
1677     state->old_bs = bdrv_lookup_bs(device, node_name, errp);
1678     if (!state->old_bs) {
1679         return;
1680     }
1681 
1682     aio_context = bdrv_get_aio_context(state->old_bs);
1683     aio_context_acquire(aio_context);
1684 
1685     /* Paired with .clean() */
1686     bdrv_drained_begin(state->old_bs);
1687 
1688     if (!bdrv_is_inserted(state->old_bs)) {
1689         error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
1690         goto out;
1691     }
1692 
1693     if (bdrv_op_is_blocked(state->old_bs,
1694                            BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
1695         goto out;
1696     }
1697 
1698     if (!bdrv_is_read_only(state->old_bs)) {
1699         if (bdrv_flush(state->old_bs)) {
1700             error_setg(errp, QERR_IO_ERROR);
1701             goto out;
1702         }
1703     }
1704 
1705     if (!bdrv_is_first_non_filter(state->old_bs)) {
1706         error_setg(errp, QERR_FEATURE_DISABLED, "snapshot");
1707         goto out;
1708     }
1709 
1710     if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
1711         BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1712         const char *format = s->has_format ? s->format : "qcow2";
1713         enum NewImageMode mode;
1714         const char *snapshot_node_name =
1715             s->has_snapshot_node_name ? s->snapshot_node_name : NULL;
1716 
1717         if (node_name && !snapshot_node_name) {
1718             error_setg(errp, "New snapshot node name missing");
1719             goto out;
1720         }
1721 
1722         if (snapshot_node_name &&
1723             bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
1724             error_setg(errp, "New snapshot node name already in use");
1725             goto out;
1726         }
1727 
1728         flags = state->old_bs->open_flags;
1729         flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ);
1730         flags |= BDRV_O_NO_BACKING;
1731 
1732         /* create new image w/backing file */
1733         mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1734         if (mode != NEW_IMAGE_MODE_EXISTING) {
1735             int64_t size = bdrv_getlength(state->old_bs);
1736             if (size < 0) {
1737                 error_setg_errno(errp, -size, "bdrv_getlength failed");
1738                 goto out;
1739             }
1740             bdrv_img_create(new_image_file, format,
1741                             state->old_bs->filename,
1742                             state->old_bs->drv->format_name,
1743                             NULL, size, flags, false, &local_err);
1744             if (local_err) {
1745                 error_propagate(errp, local_err);
1746                 goto out;
1747             }
1748         }
1749 
1750         options = qdict_new();
1751         if (s->has_snapshot_node_name) {
1752             qdict_put_str(options, "node-name", snapshot_node_name);
1753         }
1754         qdict_put_str(options, "driver", format);
1755     }
1756 
1757     state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
1758                               errp);
1759     /* We will manually add the backing_hd field to the bs later */
1760     if (!state->new_bs) {
1761         goto out;
1762     }
1763 
1764     if (bdrv_has_blk(state->new_bs)) {
1765         error_setg(errp, "The snapshot is already in use");
1766         goto out;
1767     }
1768 
1769     if (bdrv_op_is_blocked(state->new_bs, BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
1770                            errp)) {
1771         goto out;
1772     }
1773 
1774     if (state->new_bs->backing != NULL) {
1775         error_setg(errp, "The snapshot already has a backing image");
1776         goto out;
1777     }
1778 
1779     if (!state->new_bs->drv->supports_backing) {
1780         error_setg(errp, "The snapshot does not support backing images");
1781         goto out;
1782     }
1783 
1784     bdrv_set_aio_context(state->new_bs, aio_context);
1785 
1786     /* This removes our old bs and adds the new bs. This is an operation that
1787      * can fail, so we need to do it in .prepare; undoing it for abort is
1788      * always possible. */
1789     bdrv_ref(state->new_bs);
1790     bdrv_append(state->new_bs, state->old_bs, &local_err);
1791     if (local_err) {
1792         error_propagate(errp, local_err);
1793         goto out;
1794     }
1795     state->overlay_appended = true;
1796 
1797 out:
1798     aio_context_release(aio_context);
1799 }
1800 
1801 static void external_snapshot_commit(BlkActionState *common)
1802 {
1803     ExternalSnapshotState *state =
1804                              DO_UPCAST(ExternalSnapshotState, common, common);
1805     AioContext *aio_context;
1806 
1807     aio_context = bdrv_get_aio_context(state->old_bs);
1808     aio_context_acquire(aio_context);
1809 
1810     /* We don't need (or want) to use the transactional
1811      * bdrv_reopen_multiple() across all the entries at once, because we
1812      * don't want to abort all of them if one of them fails the reopen */
1813     if (!atomic_read(&state->old_bs->copy_on_read)) {
1814         bdrv_reopen(state->old_bs, state->old_bs->open_flags & ~BDRV_O_RDWR,
1815                     NULL);
1816     }
1817 
1818     aio_context_release(aio_context);
1819 }
1820 
1821 static void external_snapshot_abort(BlkActionState *common)
1822 {
1823     ExternalSnapshotState *state =
1824                              DO_UPCAST(ExternalSnapshotState, common, common);
1825     if (state->new_bs) {
1826         if (state->overlay_appended) {
1827             AioContext *aio_context;
1828 
1829             aio_context = bdrv_get_aio_context(state->old_bs);
1830             aio_context_acquire(aio_context);
1831 
1832             bdrv_ref(state->old_bs);   /* we can't let bdrv_set_backind_hd()
1833                                           close state->old_bs; we need it */
1834             bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
1835             bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
1836             bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
1837 
1838             aio_context_release(aio_context);
1839         }
1840     }
1841 }
1842 
1843 static void external_snapshot_clean(BlkActionState *common)
1844 {
1845     ExternalSnapshotState *state =
1846                              DO_UPCAST(ExternalSnapshotState, common, common);
1847     AioContext *aio_context;
1848 
1849     if (!state->old_bs) {
1850         return;
1851     }
1852 
1853     aio_context = bdrv_get_aio_context(state->old_bs);
1854     aio_context_acquire(aio_context);
1855 
1856     bdrv_drained_end(state->old_bs);
1857     bdrv_unref(state->new_bs);
1858 
1859     aio_context_release(aio_context);
1860 }
1861 
1862 typedef struct DriveBackupState {
1863     BlkActionState common;
1864     BlockDriverState *bs;
1865     BlockJob *job;
1866 } DriveBackupState;
1867 
1868 static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
1869                             Error **errp);
1870 
1871 static void drive_backup_prepare(BlkActionState *common, Error **errp)
1872 {
1873     DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
1874     BlockDriverState *bs;
1875     DriveBackup *backup;
1876     AioContext *aio_context;
1877     Error *local_err = NULL;
1878 
1879     assert(common->action->type == TRANSACTION_ACTION_KIND_DRIVE_BACKUP);
1880     backup = common->action->u.drive_backup.data;
1881 
1882     bs = qmp_get_root_bs(backup->device, errp);
1883     if (!bs) {
1884         return;
1885     }
1886 
1887     aio_context = bdrv_get_aio_context(bs);
1888     aio_context_acquire(aio_context);
1889 
1890     /* Paired with .clean() */
1891     bdrv_drained_begin(bs);
1892 
1893     state->bs = bs;
1894 
1895     state->job = do_drive_backup(backup, common->block_job_txn, &local_err);
1896     if (local_err) {
1897         error_propagate(errp, local_err);
1898         goto out;
1899     }
1900 
1901 out:
1902     aio_context_release(aio_context);
1903 }
1904 
1905 static void drive_backup_commit(BlkActionState *common)
1906 {
1907     DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
1908     AioContext *aio_context;
1909 
1910     aio_context = bdrv_get_aio_context(state->bs);
1911     aio_context_acquire(aio_context);
1912 
1913     assert(state->job);
1914     job_start(&state->job->job);
1915 
1916     aio_context_release(aio_context);
1917 }
1918 
1919 static void drive_backup_abort(BlkActionState *common)
1920 {
1921     DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
1922 
1923     if (state->job) {
1924         AioContext *aio_context;
1925 
1926         aio_context = bdrv_get_aio_context(state->bs);
1927         aio_context_acquire(aio_context);
1928 
1929         job_cancel_sync(&state->job->job);
1930 
1931         aio_context_release(aio_context);
1932     }
1933 }
1934 
1935 static void drive_backup_clean(BlkActionState *common)
1936 {
1937     DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
1938     AioContext *aio_context;
1939 
1940     if (!state->bs) {
1941         return;
1942     }
1943 
1944     aio_context = bdrv_get_aio_context(state->bs);
1945     aio_context_acquire(aio_context);
1946 
1947     bdrv_drained_end(state->bs);
1948 
1949     aio_context_release(aio_context);
1950 }
1951 
1952 typedef struct BlockdevBackupState {
1953     BlkActionState common;
1954     BlockDriverState *bs;
1955     BlockJob *job;
1956 } BlockdevBackupState;
1957 
1958 static BlockJob *do_blockdev_backup(BlockdevBackup *backup, JobTxn *txn,
1959                                     Error **errp);
1960 
1961 static void blockdev_backup_prepare(BlkActionState *common, Error **errp)
1962 {
1963     BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
1964     BlockdevBackup *backup;
1965     BlockDriverState *bs, *target;
1966     AioContext *aio_context;
1967     Error *local_err = NULL;
1968 
1969     assert(common->action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP);
1970     backup = common->action->u.blockdev_backup.data;
1971 
1972     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1973     if (!bs) {
1974         return;
1975     }
1976 
1977     target = bdrv_lookup_bs(backup->target, backup->target, errp);
1978     if (!target) {
1979         return;
1980     }
1981 
1982     aio_context = bdrv_get_aio_context(bs);
1983     if (aio_context != bdrv_get_aio_context(target)) {
1984         error_setg(errp, "Backup between two IO threads is not implemented");
1985         return;
1986     }
1987     aio_context_acquire(aio_context);
1988     state->bs = bs;
1989 
1990     /* Paired with .clean() */
1991     bdrv_drained_begin(state->bs);
1992 
1993     state->job = do_blockdev_backup(backup, common->block_job_txn, &local_err);
1994     if (local_err) {
1995         error_propagate(errp, local_err);
1996         goto out;
1997     }
1998 
1999 out:
2000     aio_context_release(aio_context);
2001 }
2002 
2003 static void blockdev_backup_commit(BlkActionState *common)
2004 {
2005     BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
2006     AioContext *aio_context;
2007 
2008     aio_context = bdrv_get_aio_context(state->bs);
2009     aio_context_acquire(aio_context);
2010 
2011     assert(state->job);
2012     job_start(&state->job->job);
2013 
2014     aio_context_release(aio_context);
2015 }
2016 
2017 static void blockdev_backup_abort(BlkActionState *common)
2018 {
2019     BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
2020 
2021     if (state->job) {
2022         AioContext *aio_context;
2023 
2024         aio_context = bdrv_get_aio_context(state->bs);
2025         aio_context_acquire(aio_context);
2026 
2027         job_cancel_sync(&state->job->job);
2028 
2029         aio_context_release(aio_context);
2030     }
2031 }
2032 
2033 static void blockdev_backup_clean(BlkActionState *common)
2034 {
2035     BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
2036     AioContext *aio_context;
2037 
2038     if (!state->bs) {
2039         return;
2040     }
2041 
2042     aio_context = bdrv_get_aio_context(state->bs);
2043     aio_context_acquire(aio_context);
2044 
2045     bdrv_drained_end(state->bs);
2046 
2047     aio_context_release(aio_context);
2048 }
2049 
2050 typedef struct BlockDirtyBitmapState {
2051     BlkActionState common;
2052     BdrvDirtyBitmap *bitmap;
2053     BlockDriverState *bs;
2054     HBitmap *backup;
2055     bool prepared;
2056     bool was_enabled;
2057 } BlockDirtyBitmapState;
2058 
2059 static void block_dirty_bitmap_add_prepare(BlkActionState *common,
2060                                            Error **errp)
2061 {
2062     Error *local_err = NULL;
2063     BlockDirtyBitmapAdd *action;
2064     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2065                                              common, common);
2066 
2067     if (action_check_completion_mode(common, errp) < 0) {
2068         return;
2069     }
2070 
2071     action = common->action->u.block_dirty_bitmap_add.data;
2072     /* AIO context taken and released within qmp_block_dirty_bitmap_add */
2073     qmp_block_dirty_bitmap_add(action->node, action->name,
2074                                action->has_granularity, action->granularity,
2075                                action->has_persistent, action->persistent,
2076                                action->has_autoload, action->autoload,
2077                                action->has_x_disabled, action->x_disabled,
2078                                &local_err);
2079 
2080     if (!local_err) {
2081         state->prepared = true;
2082     } else {
2083         error_propagate(errp, local_err);
2084     }
2085 }
2086 
2087 static void block_dirty_bitmap_add_abort(BlkActionState *common)
2088 {
2089     BlockDirtyBitmapAdd *action;
2090     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2091                                              common, common);
2092 
2093     action = common->action->u.block_dirty_bitmap_add.data;
2094     /* Should not be able to fail: IF the bitmap was added via .prepare(),
2095      * then the node reference and bitmap name must have been valid.
2096      */
2097     if (state->prepared) {
2098         qmp_block_dirty_bitmap_remove(action->node, action->name, &error_abort);
2099     }
2100 }
2101 
2102 static void block_dirty_bitmap_clear_prepare(BlkActionState *common,
2103                                              Error **errp)
2104 {
2105     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2106                                              common, common);
2107     BlockDirtyBitmap *action;
2108 
2109     if (action_check_completion_mode(common, errp) < 0) {
2110         return;
2111     }
2112 
2113     action = common->action->u.block_dirty_bitmap_clear.data;
2114     state->bitmap = block_dirty_bitmap_lookup(action->node,
2115                                               action->name,
2116                                               &state->bs,
2117                                               errp);
2118     if (!state->bitmap) {
2119         return;
2120     }
2121 
2122     if (bdrv_dirty_bitmap_frozen(state->bitmap)) {
2123         error_setg(errp, "Cannot modify a frozen bitmap");
2124         return;
2125     } else if (bdrv_dirty_bitmap_qmp_locked(state->bitmap)) {
2126         error_setg(errp, "Cannot modify a locked bitmap");
2127         return;
2128     } else if (!bdrv_dirty_bitmap_enabled(state->bitmap)) {
2129         error_setg(errp, "Cannot clear a disabled bitmap");
2130         return;
2131     } else if (bdrv_dirty_bitmap_readonly(state->bitmap)) {
2132         error_setg(errp, "Cannot clear a readonly bitmap");
2133         return;
2134     }
2135 
2136     bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
2137 }
2138 
2139 static void block_dirty_bitmap_clear_abort(BlkActionState *common)
2140 {
2141     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2142                                              common, common);
2143 
2144     if (state->backup) {
2145         bdrv_undo_clear_dirty_bitmap(state->bitmap, state->backup);
2146     }
2147 }
2148 
2149 static void block_dirty_bitmap_clear_commit(BlkActionState *common)
2150 {
2151     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2152                                              common, common);
2153 
2154     hbitmap_free(state->backup);
2155 }
2156 
2157 static void block_dirty_bitmap_enable_prepare(BlkActionState *common,
2158                                               Error **errp)
2159 {
2160     BlockDirtyBitmap *action;
2161     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2162                                              common, common);
2163 
2164     if (action_check_completion_mode(common, errp) < 0) {
2165         return;
2166     }
2167 
2168     action = common->action->u.x_block_dirty_bitmap_enable.data;
2169     state->bitmap = block_dirty_bitmap_lookup(action->node,
2170                                               action->name,
2171                                               NULL,
2172                                               errp);
2173     if (!state->bitmap) {
2174         return;
2175     }
2176 
2177     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2178     bdrv_enable_dirty_bitmap(state->bitmap);
2179 }
2180 
2181 static void block_dirty_bitmap_enable_abort(BlkActionState *common)
2182 {
2183     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2184                                              common, common);
2185 
2186     if (!state->was_enabled) {
2187         bdrv_disable_dirty_bitmap(state->bitmap);
2188     }
2189 }
2190 
2191 static void block_dirty_bitmap_disable_prepare(BlkActionState *common,
2192                                                Error **errp)
2193 {
2194     BlockDirtyBitmap *action;
2195     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2196                                              common, common);
2197 
2198     if (action_check_completion_mode(common, errp) < 0) {
2199         return;
2200     }
2201 
2202     action = common->action->u.x_block_dirty_bitmap_disable.data;
2203     state->bitmap = block_dirty_bitmap_lookup(action->node,
2204                                               action->name,
2205                                               NULL,
2206                                               errp);
2207     if (!state->bitmap) {
2208         return;
2209     }
2210 
2211     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2212     bdrv_disable_dirty_bitmap(state->bitmap);
2213 }
2214 
2215 static void block_dirty_bitmap_disable_abort(BlkActionState *common)
2216 {
2217     BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
2218                                              common, common);
2219 
2220     if (state->was_enabled) {
2221         bdrv_enable_dirty_bitmap(state->bitmap);
2222     }
2223 }
2224 
2225 static void abort_prepare(BlkActionState *common, Error **errp)
2226 {
2227     error_setg(errp, "Transaction aborted using Abort action");
2228 }
2229 
2230 static void abort_commit(BlkActionState *common)
2231 {
2232     g_assert_not_reached(); /* this action never succeeds */
2233 }
2234 
2235 static const BlkActionOps actions[] = {
2236     [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT] = {
2237         .instance_size = sizeof(ExternalSnapshotState),
2238         .prepare  = external_snapshot_prepare,
2239         .commit   = external_snapshot_commit,
2240         .abort = external_snapshot_abort,
2241         .clean = external_snapshot_clean,
2242     },
2243     [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
2244         .instance_size = sizeof(ExternalSnapshotState),
2245         .prepare  = external_snapshot_prepare,
2246         .commit   = external_snapshot_commit,
2247         .abort = external_snapshot_abort,
2248         .clean = external_snapshot_clean,
2249     },
2250     [TRANSACTION_ACTION_KIND_DRIVE_BACKUP] = {
2251         .instance_size = sizeof(DriveBackupState),
2252         .prepare = drive_backup_prepare,
2253         .commit = drive_backup_commit,
2254         .abort = drive_backup_abort,
2255         .clean = drive_backup_clean,
2256     },
2257     [TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP] = {
2258         .instance_size = sizeof(BlockdevBackupState),
2259         .prepare = blockdev_backup_prepare,
2260         .commit = blockdev_backup_commit,
2261         .abort = blockdev_backup_abort,
2262         .clean = blockdev_backup_clean,
2263     },
2264     [TRANSACTION_ACTION_KIND_ABORT] = {
2265         .instance_size = sizeof(BlkActionState),
2266         .prepare = abort_prepare,
2267         .commit = abort_commit,
2268     },
2269     [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC] = {
2270         .instance_size = sizeof(InternalSnapshotState),
2271         .prepare  = internal_snapshot_prepare,
2272         .abort = internal_snapshot_abort,
2273         .clean = internal_snapshot_clean,
2274     },
2275     [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD] = {
2276         .instance_size = sizeof(BlockDirtyBitmapState),
2277         .prepare = block_dirty_bitmap_add_prepare,
2278         .abort = block_dirty_bitmap_add_abort,
2279     },
2280     [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR] = {
2281         .instance_size = sizeof(BlockDirtyBitmapState),
2282         .prepare = block_dirty_bitmap_clear_prepare,
2283         .commit = block_dirty_bitmap_clear_commit,
2284         .abort = block_dirty_bitmap_clear_abort,
2285     },
2286     [TRANSACTION_ACTION_KIND_X_BLOCK_DIRTY_BITMAP_ENABLE] = {
2287         .instance_size = sizeof(BlockDirtyBitmapState),
2288         .prepare = block_dirty_bitmap_enable_prepare,
2289         .abort = block_dirty_bitmap_enable_abort,
2290     },
2291     [TRANSACTION_ACTION_KIND_X_BLOCK_DIRTY_BITMAP_DISABLE] = {
2292         .instance_size = sizeof(BlockDirtyBitmapState),
2293         .prepare = block_dirty_bitmap_disable_prepare,
2294         .abort = block_dirty_bitmap_disable_abort,
2295      }
2296 };
2297 
2298 /**
2299  * Allocate a TransactionProperties structure if necessary, and fill
2300  * that structure with desired defaults if they are unset.
2301  */
2302 static TransactionProperties *get_transaction_properties(
2303     TransactionProperties *props)
2304 {
2305     if (!props) {
2306         props = g_new0(TransactionProperties, 1);
2307     }
2308 
2309     if (!props->has_completion_mode) {
2310         props->has_completion_mode = true;
2311         props->completion_mode = ACTION_COMPLETION_MODE_INDIVIDUAL;
2312     }
2313 
2314     return props;
2315 }
2316 
2317 /*
2318  * 'Atomic' group operations.  The operations are performed as a set, and if
2319  * any fail then we roll back all operations in the group.
2320  */
2321 void qmp_transaction(TransactionActionList *dev_list,
2322                      bool has_props,
2323                      struct TransactionProperties *props,
2324                      Error **errp)
2325 {
2326     TransactionActionList *dev_entry = dev_list;
2327     JobTxn *block_job_txn = NULL;
2328     BlkActionState *state, *next;
2329     Error *local_err = NULL;
2330 
2331     QSIMPLEQ_HEAD(snap_bdrv_states, BlkActionState) snap_bdrv_states;
2332     QSIMPLEQ_INIT(&snap_bdrv_states);
2333 
2334     /* Does this transaction get canceled as a group on failure?
2335      * If not, we don't really need to make a JobTxn.
2336      */
2337     props = get_transaction_properties(props);
2338     if (props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
2339         block_job_txn = job_txn_new();
2340     }
2341 
2342     /* drain all i/o before any operations */
2343     bdrv_drain_all();
2344 
2345     /* We don't do anything in this loop that commits us to the operations */
2346     while (NULL != dev_entry) {
2347         TransactionAction *dev_info = NULL;
2348         const BlkActionOps *ops;
2349 
2350         dev_info = dev_entry->value;
2351         dev_entry = dev_entry->next;
2352 
2353         assert(dev_info->type < ARRAY_SIZE(actions));
2354 
2355         ops = &actions[dev_info->type];
2356         assert(ops->instance_size > 0);
2357 
2358         state = g_malloc0(ops->instance_size);
2359         state->ops = ops;
2360         state->action = dev_info;
2361         state->block_job_txn = block_job_txn;
2362         state->txn_props = props;
2363         QSIMPLEQ_INSERT_TAIL(&snap_bdrv_states, state, entry);
2364 
2365         state->ops->prepare(state, &local_err);
2366         if (local_err) {
2367             error_propagate(errp, local_err);
2368             goto delete_and_fail;
2369         }
2370     }
2371 
2372     QSIMPLEQ_FOREACH(state, &snap_bdrv_states, entry) {
2373         if (state->ops->commit) {
2374             state->ops->commit(state);
2375         }
2376     }
2377 
2378     /* success */
2379     goto exit;
2380 
2381 delete_and_fail:
2382     /* failure, and it is all-or-none; roll back all operations */
2383     QSIMPLEQ_FOREACH(state, &snap_bdrv_states, entry) {
2384         if (state->ops->abort) {
2385             state->ops->abort(state);
2386         }
2387     }
2388 exit:
2389     QSIMPLEQ_FOREACH_SAFE(state, &snap_bdrv_states, entry, next) {
2390         if (state->ops->clean) {
2391             state->ops->clean(state);
2392         }
2393         g_free(state);
2394     }
2395     if (!has_props) {
2396         qapi_free_TransactionProperties(props);
2397     }
2398     job_txn_unref(block_job_txn);
2399 }
2400 
2401 void qmp_eject(bool has_device, const char *device,
2402                bool has_id, const char *id,
2403                bool has_force, bool force, Error **errp)
2404 {
2405     Error *local_err = NULL;
2406     int rc;
2407 
2408     if (!has_force) {
2409         force = false;
2410     }
2411 
2412     rc = do_open_tray(has_device ? device : NULL,
2413                       has_id ? id : NULL,
2414                       force, &local_err);
2415     if (rc && rc != -ENOSYS) {
2416         error_propagate(errp, local_err);
2417         return;
2418     }
2419     error_free(local_err);
2420 
2421     blockdev_remove_medium(has_device, device, has_id, id, errp);
2422 }
2423 
2424 void qmp_block_passwd(bool has_device, const char *device,
2425                       bool has_node_name, const char *node_name,
2426                       const char *password, Error **errp)
2427 {
2428     error_setg(errp,
2429                "Setting block passwords directly is no longer supported");
2430 }
2431 
2432 /*
2433  * Attempt to open the tray of @device.
2434  * If @force, ignore its tray lock.
2435  * Else, if the tray is locked, don't open it, but ask the guest to open it.
2436  * On error, store an error through @errp and return -errno.
2437  * If @device does not exist, return -ENODEV.
2438  * If it has no removable media, return -ENOTSUP.
2439  * If it has no tray, return -ENOSYS.
2440  * If the guest was asked to open the tray, return -EINPROGRESS.
2441  * Else, return 0.
2442  */
2443 static int do_open_tray(const char *blk_name, const char *qdev_id,
2444                         bool force, Error **errp)
2445 {
2446     BlockBackend *blk;
2447     const char *device = qdev_id ?: blk_name;
2448     bool locked;
2449 
2450     blk = qmp_get_blk(blk_name, qdev_id, errp);
2451     if (!blk) {
2452         return -ENODEV;
2453     }
2454 
2455     if (!blk_dev_has_removable_media(blk)) {
2456         error_setg(errp, "Device '%s' is not removable", device);
2457         return -ENOTSUP;
2458     }
2459 
2460     if (!blk_dev_has_tray(blk)) {
2461         error_setg(errp, "Device '%s' does not have a tray", device);
2462         return -ENOSYS;
2463     }
2464 
2465     if (blk_dev_is_tray_open(blk)) {
2466         return 0;
2467     }
2468 
2469     locked = blk_dev_is_medium_locked(blk);
2470     if (locked) {
2471         blk_dev_eject_request(blk, force);
2472     }
2473 
2474     if (!locked || force) {
2475         blk_dev_change_media_cb(blk, false, &error_abort);
2476     }
2477 
2478     if (locked && !force) {
2479         error_setg(errp, "Device '%s' is locked and force was not specified, "
2480                    "wait for tray to open and try again", device);
2481         return -EINPROGRESS;
2482     }
2483 
2484     return 0;
2485 }
2486 
2487 void qmp_blockdev_open_tray(bool has_device, const char *device,
2488                             bool has_id, const char *id,
2489                             bool has_force, bool force,
2490                             Error **errp)
2491 {
2492     Error *local_err = NULL;
2493     int rc;
2494 
2495     if (!has_force) {
2496         force = false;
2497     }
2498     rc = do_open_tray(has_device ? device : NULL,
2499                       has_id ? id : NULL,
2500                       force, &local_err);
2501     if (rc && rc != -ENOSYS && rc != -EINPROGRESS) {
2502         error_propagate(errp, local_err);
2503         return;
2504     }
2505     error_free(local_err);
2506 }
2507 
2508 void qmp_blockdev_close_tray(bool has_device, const char *device,
2509                              bool has_id, const char *id,
2510                              Error **errp)
2511 {
2512     BlockBackend *blk;
2513     Error *local_err = NULL;
2514 
2515     device = has_device ? device : NULL;
2516     id = has_id ? id : NULL;
2517 
2518     blk = qmp_get_blk(device, id, errp);
2519     if (!blk) {
2520         return;
2521     }
2522 
2523     if (!blk_dev_has_removable_media(blk)) {
2524         error_setg(errp, "Device '%s' is not removable", device ?: id);
2525         return;
2526     }
2527 
2528     if (!blk_dev_has_tray(blk)) {
2529         /* Ignore this command on tray-less devices */
2530         return;
2531     }
2532 
2533     if (!blk_dev_is_tray_open(blk)) {
2534         return;
2535     }
2536 
2537     blk_dev_change_media_cb(blk, true, &local_err);
2538     if (local_err) {
2539         error_propagate(errp, local_err);
2540         return;
2541     }
2542 }
2543 
2544 static void blockdev_remove_medium(bool has_device, const char *device,
2545                                    bool has_id, const char *id, Error **errp)
2546 {
2547     BlockBackend *blk;
2548     BlockDriverState *bs;
2549     AioContext *aio_context;
2550     bool has_attached_device;
2551 
2552     device = has_device ? device : NULL;
2553     id = has_id ? id : NULL;
2554 
2555     blk = qmp_get_blk(device, id, errp);
2556     if (!blk) {
2557         return;
2558     }
2559 
2560     /* For BBs without a device, we can exchange the BDS tree at will */
2561     has_attached_device = blk_get_attached_dev(blk);
2562 
2563     if (has_attached_device && !blk_dev_has_removable_media(blk)) {
2564         error_setg(errp, "Device '%s' is not removable", device ?: id);
2565         return;
2566     }
2567 
2568     if (has_attached_device && blk_dev_has_tray(blk) &&
2569         !blk_dev_is_tray_open(blk))
2570     {
2571         error_setg(errp, "Tray of device '%s' is not open", device ?: id);
2572         return;
2573     }
2574 
2575     bs = blk_bs(blk);
2576     if (!bs) {
2577         return;
2578     }
2579 
2580     aio_context = bdrv_get_aio_context(bs);
2581     aio_context_acquire(aio_context);
2582 
2583     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
2584         goto out;
2585     }
2586 
2587     blk_remove_bs(blk);
2588 
2589     if (!blk_dev_has_tray(blk)) {
2590         /* For tray-less devices, blockdev-open-tray is a no-op (or may not be
2591          * called at all); therefore, the medium needs to be ejected here.
2592          * Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load
2593          * value passed here (i.e. false). */
2594         blk_dev_change_media_cb(blk, false, &error_abort);
2595     }
2596 
2597 out:
2598     aio_context_release(aio_context);
2599 }
2600 
2601 void qmp_blockdev_remove_medium(const char *id, Error **errp)
2602 {
2603     blockdev_remove_medium(false, NULL, true, id, errp);
2604 }
2605 
2606 static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
2607                                             BlockDriverState *bs, Error **errp)
2608 {
2609     Error *local_err = NULL;
2610     bool has_device;
2611     int ret;
2612 
2613     /* For BBs without a device, we can exchange the BDS tree at will */
2614     has_device = blk_get_attached_dev(blk);
2615 
2616     if (has_device && !blk_dev_has_removable_media(blk)) {
2617         error_setg(errp, "Device is not removable");
2618         return;
2619     }
2620 
2621     if (has_device && blk_dev_has_tray(blk) && !blk_dev_is_tray_open(blk)) {
2622         error_setg(errp, "Tray of the device is not open");
2623         return;
2624     }
2625 
2626     if (blk_bs(blk)) {
2627         error_setg(errp, "There already is a medium in the device");
2628         return;
2629     }
2630 
2631     ret = blk_insert_bs(blk, bs, errp);
2632     if (ret < 0) {
2633         return;
2634     }
2635 
2636     if (!blk_dev_has_tray(blk)) {
2637         /* For tray-less devices, blockdev-close-tray is a no-op (or may not be
2638          * called at all); therefore, the medium needs to be pushed into the
2639          * slot here.
2640          * Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load
2641          * value passed here (i.e. true). */
2642         blk_dev_change_media_cb(blk, true, &local_err);
2643         if (local_err) {
2644             error_propagate(errp, local_err);
2645             blk_remove_bs(blk);
2646             return;
2647         }
2648     }
2649 }
2650 
2651 static void blockdev_insert_medium(bool has_device, const char *device,
2652                                    bool has_id, const char *id,
2653                                    const char *node_name, Error **errp)
2654 {
2655     BlockBackend *blk;
2656     BlockDriverState *bs;
2657 
2658     blk = qmp_get_blk(has_device ? device : NULL,
2659                       has_id ? id : NULL,
2660                       errp);
2661     if (!blk) {
2662         return;
2663     }
2664 
2665     bs = bdrv_find_node(node_name);
2666     if (!bs) {
2667         error_setg(errp, "Node '%s' not found", node_name);
2668         return;
2669     }
2670 
2671     if (bdrv_has_blk(bs)) {
2672         error_setg(errp, "Node '%s' is already in use", node_name);
2673         return;
2674     }
2675 
2676     qmp_blockdev_insert_anon_medium(blk, bs, errp);
2677 }
2678 
2679 void qmp_blockdev_insert_medium(const char *id, const char *node_name,
2680                                 Error **errp)
2681 {
2682     blockdev_insert_medium(false, NULL, true, id, node_name, errp);
2683 }
2684 
2685 void qmp_blockdev_change_medium(bool has_device, const char *device,
2686                                 bool has_id, const char *id,
2687                                 const char *filename,
2688                                 bool has_format, const char *format,
2689                                 bool has_read_only,
2690                                 BlockdevChangeReadOnlyMode read_only,
2691                                 Error **errp)
2692 {
2693     BlockBackend *blk;
2694     BlockDriverState *medium_bs = NULL;
2695     int bdrv_flags;
2696     bool detect_zeroes;
2697     int rc;
2698     QDict *options = NULL;
2699     Error *err = NULL;
2700 
2701     blk = qmp_get_blk(has_device ? device : NULL,
2702                       has_id ? id : NULL,
2703                       errp);
2704     if (!blk) {
2705         goto fail;
2706     }
2707 
2708     if (blk_bs(blk)) {
2709         blk_update_root_state(blk);
2710     }
2711 
2712     bdrv_flags = blk_get_open_flags_from_root_state(blk);
2713     bdrv_flags &= ~(BDRV_O_TEMPORARY | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING |
2714         BDRV_O_PROTOCOL);
2715 
2716     if (!has_read_only) {
2717         read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN;
2718     }
2719 
2720     switch (read_only) {
2721     case BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN:
2722         break;
2723 
2724     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_ONLY:
2725         bdrv_flags &= ~BDRV_O_RDWR;
2726         break;
2727 
2728     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_WRITE:
2729         bdrv_flags |= BDRV_O_RDWR;
2730         break;
2731 
2732     default:
2733         abort();
2734     }
2735 
2736     options = qdict_new();
2737     detect_zeroes = blk_get_detect_zeroes_from_root_state(blk);
2738     qdict_put_str(options, "detect-zeroes", detect_zeroes ? "on" : "off");
2739 
2740     if (has_format) {
2741         qdict_put_str(options, "driver", format);
2742     }
2743 
2744     medium_bs = bdrv_open(filename, NULL, options, bdrv_flags, errp);
2745     if (!medium_bs) {
2746         goto fail;
2747     }
2748 
2749     rc = do_open_tray(has_device ? device : NULL,
2750                       has_id ? id : NULL,
2751                       false, &err);
2752     if (rc && rc != -ENOSYS) {
2753         error_propagate(errp, err);
2754         goto fail;
2755     }
2756     error_free(err);
2757     err = NULL;
2758 
2759     blockdev_remove_medium(has_device, device, has_id, id, &err);
2760     if (err) {
2761         error_propagate(errp, err);
2762         goto fail;
2763     }
2764 
2765     qmp_blockdev_insert_anon_medium(blk, medium_bs, &err);
2766     if (err) {
2767         error_propagate(errp, err);
2768         goto fail;
2769     }
2770 
2771     qmp_blockdev_close_tray(has_device, device, has_id, id, errp);
2772 
2773 fail:
2774     /* If the medium has been inserted, the device has its own reference, so
2775      * ours must be relinquished; and if it has not been inserted successfully,
2776      * the reference must be relinquished anyway */
2777     bdrv_unref(medium_bs);
2778 }
2779 
2780 /* throttling disk I/O limits */
2781 void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
2782 {
2783     ThrottleConfig cfg;
2784     BlockDriverState *bs;
2785     BlockBackend *blk;
2786     AioContext *aio_context;
2787 
2788     blk = qmp_get_blk(arg->has_device ? arg->device : NULL,
2789                       arg->has_id ? arg->id : NULL,
2790                       errp);
2791     if (!blk) {
2792         return;
2793     }
2794 
2795     aio_context = blk_get_aio_context(blk);
2796     aio_context_acquire(aio_context);
2797 
2798     bs = blk_bs(blk);
2799     if (!bs) {
2800         error_setg(errp, "Device has no medium");
2801         goto out;
2802     }
2803 
2804     throttle_config_init(&cfg);
2805     cfg.buckets[THROTTLE_BPS_TOTAL].avg = arg->bps;
2806     cfg.buckets[THROTTLE_BPS_READ].avg  = arg->bps_rd;
2807     cfg.buckets[THROTTLE_BPS_WRITE].avg = arg->bps_wr;
2808 
2809     cfg.buckets[THROTTLE_OPS_TOTAL].avg = arg->iops;
2810     cfg.buckets[THROTTLE_OPS_READ].avg  = arg->iops_rd;
2811     cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
2812 
2813     if (arg->has_bps_max) {
2814         cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
2815     }
2816     if (arg->has_bps_rd_max) {
2817         cfg.buckets[THROTTLE_BPS_READ].max = arg->bps_rd_max;
2818     }
2819     if (arg->has_bps_wr_max) {
2820         cfg.buckets[THROTTLE_BPS_WRITE].max = arg->bps_wr_max;
2821     }
2822     if (arg->has_iops_max) {
2823         cfg.buckets[THROTTLE_OPS_TOTAL].max = arg->iops_max;
2824     }
2825     if (arg->has_iops_rd_max) {
2826         cfg.buckets[THROTTLE_OPS_READ].max = arg->iops_rd_max;
2827     }
2828     if (arg->has_iops_wr_max) {
2829         cfg.buckets[THROTTLE_OPS_WRITE].max = arg->iops_wr_max;
2830     }
2831 
2832     if (arg->has_bps_max_length) {
2833         cfg.buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_max_length;
2834     }
2835     if (arg->has_bps_rd_max_length) {
2836         cfg.buckets[THROTTLE_BPS_READ].burst_length = arg->bps_rd_max_length;
2837     }
2838     if (arg->has_bps_wr_max_length) {
2839         cfg.buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_wr_max_length;
2840     }
2841     if (arg->has_iops_max_length) {
2842         cfg.buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_max_length;
2843     }
2844     if (arg->has_iops_rd_max_length) {
2845         cfg.buckets[THROTTLE_OPS_READ].burst_length = arg->iops_rd_max_length;
2846     }
2847     if (arg->has_iops_wr_max_length) {
2848         cfg.buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_wr_max_length;
2849     }
2850 
2851     if (arg->has_iops_size) {
2852         cfg.op_size = arg->iops_size;
2853     }
2854 
2855     if (!throttle_is_valid(&cfg, errp)) {
2856         goto out;
2857     }
2858 
2859     if (throttle_enabled(&cfg)) {
2860         /* Enable I/O limits if they're not enabled yet, otherwise
2861          * just update the throttling group. */
2862         if (!blk_get_public(blk)->throttle_group_member.throttle_state) {
2863             blk_io_limits_enable(blk,
2864                                  arg->has_group ? arg->group :
2865                                  arg->has_device ? arg->device :
2866                                  arg->id);
2867         } else if (arg->has_group) {
2868             blk_io_limits_update_group(blk, arg->group);
2869         }
2870         /* Set the new throttling configuration */
2871         blk_set_io_limits(blk, &cfg);
2872     } else if (blk_get_public(blk)->throttle_group_member.throttle_state) {
2873         /* If all throttling settings are set to 0, disable I/O limits */
2874         blk_io_limits_disable(blk);
2875     }
2876 
2877 out:
2878     aio_context_release(aio_context);
2879 }
2880 
2881 void qmp_block_dirty_bitmap_add(const char *node, const char *name,
2882                                 bool has_granularity, uint32_t granularity,
2883                                 bool has_persistent, bool persistent,
2884                                 bool has_autoload, bool autoload,
2885                                 bool has_disabled, bool disabled,
2886                                 Error **errp)
2887 {
2888     BlockDriverState *bs;
2889     BdrvDirtyBitmap *bitmap;
2890 
2891     if (!name || name[0] == '\0') {
2892         error_setg(errp, "Bitmap name cannot be empty");
2893         return;
2894     }
2895 
2896     bs = bdrv_lookup_bs(node, node, errp);
2897     if (!bs) {
2898         return;
2899     }
2900 
2901     if (has_granularity) {
2902         if (granularity < 512 || !is_power_of_2(granularity)) {
2903             error_setg(errp, "Granularity must be power of 2 "
2904                              "and at least 512");
2905             return;
2906         }
2907     } else {
2908         /* Default to cluster size, if available: */
2909         granularity = bdrv_get_default_bitmap_granularity(bs);
2910     }
2911 
2912     if (!has_persistent) {
2913         persistent = false;
2914     }
2915 
2916     if (has_autoload) {
2917         warn_report("Autoload option is deprecated and its value is ignored");
2918     }
2919 
2920     if (!has_disabled) {
2921         disabled = false;
2922     }
2923 
2924     if (persistent &&
2925         !bdrv_can_store_new_dirty_bitmap(bs, name, granularity, errp))
2926     {
2927         return;
2928     }
2929 
2930     bitmap = bdrv_create_dirty_bitmap(bs, granularity, name, errp);
2931     if (bitmap == NULL) {
2932         return;
2933     }
2934 
2935     if (disabled) {
2936         bdrv_disable_dirty_bitmap(bitmap);
2937     }
2938 
2939     bdrv_dirty_bitmap_set_persistance(bitmap, persistent);
2940 }
2941 
2942 void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
2943                                    Error **errp)
2944 {
2945     BlockDriverState *bs;
2946     BdrvDirtyBitmap *bitmap;
2947     Error *local_err = NULL;
2948 
2949     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2950     if (!bitmap || !bs) {
2951         return;
2952     }
2953 
2954     if (bdrv_dirty_bitmap_frozen(bitmap)) {
2955         error_setg(errp,
2956                    "Bitmap '%s' is currently frozen and cannot be removed",
2957                    name);
2958         return;
2959     } else if (bdrv_dirty_bitmap_qmp_locked(bitmap)) {
2960         error_setg(errp,
2961                    "Bitmap '%s' is currently locked and cannot be removed",
2962                    name);
2963         return;
2964     }
2965 
2966     if (bdrv_dirty_bitmap_get_persistance(bitmap)) {
2967         bdrv_remove_persistent_dirty_bitmap(bs, name, &local_err);
2968         if (local_err != NULL) {
2969             error_propagate(errp, local_err);
2970             return;
2971         }
2972     }
2973 
2974     bdrv_release_dirty_bitmap(bs, bitmap);
2975 }
2976 
2977 /**
2978  * Completely clear a bitmap, for the purposes of synchronizing a bitmap
2979  * immediately after a full backup operation.
2980  */
2981 void qmp_block_dirty_bitmap_clear(const char *node, const char *name,
2982                                   Error **errp)
2983 {
2984     BdrvDirtyBitmap *bitmap;
2985     BlockDriverState *bs;
2986 
2987     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2988     if (!bitmap || !bs) {
2989         return;
2990     }
2991 
2992     if (bdrv_dirty_bitmap_frozen(bitmap)) {
2993         error_setg(errp,
2994                    "Bitmap '%s' is currently frozen and cannot be modified",
2995                    name);
2996         return;
2997     } else if (bdrv_dirty_bitmap_qmp_locked(bitmap)) {
2998         error_setg(errp,
2999                    "Bitmap '%s' is currently locked and cannot be modified",
3000                    name);
3001         return;
3002     } else if (!bdrv_dirty_bitmap_enabled(bitmap)) {
3003         error_setg(errp,
3004                    "Bitmap '%s' is currently disabled and cannot be cleared",
3005                    name);
3006         return;
3007     } else if (bdrv_dirty_bitmap_readonly(bitmap)) {
3008         error_setg(errp, "Bitmap '%s' is readonly and cannot be cleared", name);
3009         return;
3010     }
3011 
3012     bdrv_clear_dirty_bitmap(bitmap, NULL);
3013 }
3014 
3015 void qmp_x_block_dirty_bitmap_enable(const char *node, const char *name,
3016                                    Error **errp)
3017 {
3018     BlockDriverState *bs;
3019     BdrvDirtyBitmap *bitmap;
3020 
3021     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
3022     if (!bitmap) {
3023         return;
3024     }
3025 
3026     if (bdrv_dirty_bitmap_frozen(bitmap)) {
3027         error_setg(errp,
3028                    "Bitmap '%s' is currently frozen and cannot be enabled",
3029                    name);
3030         return;
3031     }
3032 
3033     bdrv_enable_dirty_bitmap(bitmap);
3034 }
3035 
3036 void qmp_x_block_dirty_bitmap_disable(const char *node, const char *name,
3037                                     Error **errp)
3038 {
3039     BlockDriverState *bs;
3040     BdrvDirtyBitmap *bitmap;
3041 
3042     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
3043     if (!bitmap) {
3044         return;
3045     }
3046 
3047     if (bdrv_dirty_bitmap_frozen(bitmap)) {
3048         error_setg(errp,
3049                    "Bitmap '%s' is currently frozen and cannot be disabled",
3050                    name);
3051         return;
3052     }
3053 
3054     bdrv_disable_dirty_bitmap(bitmap);
3055 }
3056 
3057 void qmp_x_block_dirty_bitmap_merge(const char *node, const char *dst_name,
3058                                     const char *src_name, Error **errp)
3059 {
3060     BlockDriverState *bs;
3061     BdrvDirtyBitmap *dst, *src;
3062 
3063     dst = block_dirty_bitmap_lookup(node, dst_name, &bs, errp);
3064     if (!dst) {
3065         return;
3066     }
3067 
3068     if (bdrv_dirty_bitmap_frozen(dst)) {
3069         error_setg(errp, "Bitmap '%s' is frozen and cannot be modified",
3070                    dst_name);
3071         return;
3072     } else if (bdrv_dirty_bitmap_readonly(dst)) {
3073         error_setg(errp, "Bitmap '%s' is readonly and cannot be modified",
3074                    dst_name);
3075         return;
3076     }
3077 
3078     src = bdrv_find_dirty_bitmap(bs, src_name);
3079     if (!src) {
3080         error_setg(errp, "Dirty bitmap '%s' not found", src_name);
3081         return;
3082     }
3083 
3084     bdrv_merge_dirty_bitmap(dst, src, errp);
3085 }
3086 
3087 BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
3088                                                               const char *name,
3089                                                               Error **errp)
3090 {
3091     BdrvDirtyBitmap *bitmap;
3092     BlockDriverState *bs;
3093     BlockDirtyBitmapSha256 *ret = NULL;
3094     char *sha256;
3095 
3096     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
3097     if (!bitmap || !bs) {
3098         return NULL;
3099     }
3100 
3101     sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
3102     if (sha256 == NULL) {
3103         return NULL;
3104     }
3105 
3106     ret = g_new(BlockDirtyBitmapSha256, 1);
3107     ret->sha256 = sha256;
3108 
3109     return ret;
3110 }
3111 
3112 void hmp_drive_del(Monitor *mon, const QDict *qdict)
3113 {
3114     const char *id = qdict_get_str(qdict, "id");
3115     BlockBackend *blk;
3116     BlockDriverState *bs;
3117     AioContext *aio_context;
3118     Error *local_err = NULL;
3119 
3120     bs = bdrv_find_node(id);
3121     if (bs) {
3122         qmp_blockdev_del(id, &local_err);
3123         if (local_err) {
3124             error_report_err(local_err);
3125         }
3126         return;
3127     }
3128 
3129     blk = blk_by_name(id);
3130     if (!blk) {
3131         error_report("Device '%s' not found", id);
3132         return;
3133     }
3134 
3135     if (!blk_legacy_dinfo(blk)) {
3136         error_report("Deleting device added with blockdev-add"
3137                      " is not supported");
3138         return;
3139     }
3140 
3141     aio_context = blk_get_aio_context(blk);
3142     aio_context_acquire(aio_context);
3143 
3144     bs = blk_bs(blk);
3145     if (bs) {
3146         if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
3147             error_report_err(local_err);
3148             aio_context_release(aio_context);
3149             return;
3150         }
3151 
3152         blk_remove_bs(blk);
3153     }
3154 
3155     /* Make the BlockBackend and the attached BlockDriverState anonymous */
3156     monitor_remove_blk(blk);
3157 
3158     /* If this BlockBackend has a device attached to it, its refcount will be
3159      * decremented when the device is removed; otherwise we have to do so here.
3160      */
3161     if (blk_get_attached_dev(blk)) {
3162         /* Further I/O must not pause the guest */
3163         blk_set_on_error(blk, BLOCKDEV_ON_ERROR_REPORT,
3164                          BLOCKDEV_ON_ERROR_REPORT);
3165     } else {
3166         blk_unref(blk);
3167     }
3168 
3169     aio_context_release(aio_context);
3170 }
3171 
3172 void qmp_block_resize(bool has_device, const char *device,
3173                       bool has_node_name, const char *node_name,
3174                       int64_t size, Error **errp)
3175 {
3176     Error *local_err = NULL;
3177     BlockBackend *blk = NULL;
3178     BlockDriverState *bs;
3179     AioContext *aio_context;
3180     int ret;
3181 
3182     bs = bdrv_lookup_bs(has_device ? device : NULL,
3183                         has_node_name ? node_name : NULL,
3184                         &local_err);
3185     if (local_err) {
3186         error_propagate(errp, local_err);
3187         return;
3188     }
3189 
3190     aio_context = bdrv_get_aio_context(bs);
3191     aio_context_acquire(aio_context);
3192 
3193     if (!bdrv_is_first_non_filter(bs)) {
3194         error_setg(errp, QERR_FEATURE_DISABLED, "resize");
3195         goto out;
3196     }
3197 
3198     if (size < 0) {
3199         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
3200         goto out;
3201     }
3202 
3203     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
3204         error_setg(errp, QERR_DEVICE_IN_USE, device);
3205         goto out;
3206     }
3207 
3208     blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL);
3209     ret = blk_insert_bs(blk, bs, errp);
3210     if (ret < 0) {
3211         goto out;
3212     }
3213 
3214     bdrv_drained_begin(bs);
3215     ret = blk_truncate(blk, size, PREALLOC_MODE_OFF, errp);
3216     bdrv_drained_end(bs);
3217 
3218 out:
3219     blk_unref(blk);
3220     aio_context_release(aio_context);
3221 }
3222 
3223 void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
3224                       bool has_base, const char *base,
3225                       bool has_base_node, const char *base_node,
3226                       bool has_backing_file, const char *backing_file,
3227                       bool has_speed, int64_t speed,
3228                       bool has_on_error, BlockdevOnError on_error,
3229                       Error **errp)
3230 {
3231     BlockDriverState *bs, *iter;
3232     BlockDriverState *base_bs = NULL;
3233     AioContext *aio_context;
3234     Error *local_err = NULL;
3235     const char *base_name = NULL;
3236 
3237     if (!has_on_error) {
3238         on_error = BLOCKDEV_ON_ERROR_REPORT;
3239     }
3240 
3241     bs = bdrv_lookup_bs(device, device, errp);
3242     if (!bs) {
3243         return;
3244     }
3245 
3246     aio_context = bdrv_get_aio_context(bs);
3247     aio_context_acquire(aio_context);
3248 
3249     if (has_base && has_base_node) {
3250         error_setg(errp, "'base' and 'base-node' cannot be specified "
3251                    "at the same time");
3252         goto out;
3253     }
3254 
3255     if (has_base) {
3256         base_bs = bdrv_find_backing_image(bs, base);
3257         if (base_bs == NULL) {
3258             error_setg(errp, QERR_BASE_NOT_FOUND, base);
3259             goto out;
3260         }
3261         assert(bdrv_get_aio_context(base_bs) == aio_context);
3262         base_name = base;
3263     }
3264 
3265     if (has_base_node) {
3266         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
3267         if (!base_bs) {
3268             goto out;
3269         }
3270         if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
3271             error_setg(errp, "Node '%s' is not a backing image of '%s'",
3272                        base_node, device);
3273             goto out;
3274         }
3275         assert(bdrv_get_aio_context(base_bs) == aio_context);
3276         base_name = base_bs->filename;
3277     }
3278 
3279     /* Check for op blockers in the whole chain between bs and base */
3280     for (iter = bs; iter && iter != base_bs; iter = backing_bs(iter)) {
3281         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
3282             goto out;
3283         }
3284     }
3285 
3286     /* if we are streaming the entire chain, the result will have no backing
3287      * file, and specifying one is therefore an error */
3288     if (base_bs == NULL && has_backing_file) {
3289         error_setg(errp, "backing file specified, but streaming the "
3290                          "entire chain");
3291         goto out;
3292     }
3293 
3294     /* backing_file string overrides base bs filename */
3295     base_name = has_backing_file ? backing_file : base_name;
3296 
3297     stream_start(has_job_id ? job_id : NULL, bs, base_bs, base_name,
3298                  has_speed ? speed : 0, on_error, &local_err);
3299     if (local_err) {
3300         error_propagate(errp, local_err);
3301         goto out;
3302     }
3303 
3304     trace_qmp_block_stream(bs, bs->job);
3305 
3306 out:
3307     aio_context_release(aio_context);
3308 }
3309 
3310 void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
3311                       bool has_base, const char *base,
3312                       bool has_top, const char *top,
3313                       bool has_backing_file, const char *backing_file,
3314                       bool has_speed, int64_t speed,
3315                       bool has_filter_node_name, const char *filter_node_name,
3316                       Error **errp)
3317 {
3318     BlockDriverState *bs;
3319     BlockDriverState *iter;
3320     BlockDriverState *base_bs, *top_bs;
3321     AioContext *aio_context;
3322     Error *local_err = NULL;
3323     /* This will be part of the QMP command, if/when the
3324      * BlockdevOnError change for blkmirror makes it in
3325      */
3326     BlockdevOnError on_error = BLOCKDEV_ON_ERROR_REPORT;
3327 
3328     if (!has_speed) {
3329         speed = 0;
3330     }
3331     if (!has_filter_node_name) {
3332         filter_node_name = NULL;
3333     }
3334 
3335     /* Important Note:
3336      *  libvirt relies on the DeviceNotFound error class in order to probe for
3337      *  live commit feature versions; for this to work, we must make sure to
3338      *  perform the device lookup before any generic errors that may occur in a
3339      *  scenario in which all optional arguments are omitted. */
3340     bs = qmp_get_root_bs(device, &local_err);
3341     if (!bs) {
3342         bs = bdrv_lookup_bs(device, device, NULL);
3343         if (!bs) {
3344             error_free(local_err);
3345             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
3346                       "Device '%s' not found", device);
3347         } else {
3348             error_propagate(errp, local_err);
3349         }
3350         return;
3351     }
3352 
3353     aio_context = bdrv_get_aio_context(bs);
3354     aio_context_acquire(aio_context);
3355 
3356     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
3357         goto out;
3358     }
3359 
3360     /* default top_bs is the active layer */
3361     top_bs = bs;
3362 
3363     if (has_top && top) {
3364         if (strcmp(bs->filename, top) != 0) {
3365             top_bs = bdrv_find_backing_image(bs, top);
3366         }
3367     }
3368 
3369     if (top_bs == NULL) {
3370         error_setg(errp, "Top image file %s not found", top ? top : "NULL");
3371         goto out;
3372     }
3373 
3374     assert(bdrv_get_aio_context(top_bs) == aio_context);
3375 
3376     if (has_base && base) {
3377         base_bs = bdrv_find_backing_image(top_bs, base);
3378     } else {
3379         base_bs = bdrv_find_base(top_bs);
3380     }
3381 
3382     if (base_bs == NULL) {
3383         error_setg(errp, QERR_BASE_NOT_FOUND, base ? base : "NULL");
3384         goto out;
3385     }
3386 
3387     assert(bdrv_get_aio_context(base_bs) == aio_context);
3388 
3389     for (iter = top_bs; iter != backing_bs(base_bs); iter = backing_bs(iter)) {
3390         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
3391             goto out;
3392         }
3393     }
3394 
3395     /* Do not allow attempts to commit an image into itself */
3396     if (top_bs == base_bs) {
3397         error_setg(errp, "cannot commit an image into itself");
3398         goto out;
3399     }
3400 
3401     if (top_bs == bs) {
3402         if (has_backing_file) {
3403             error_setg(errp, "'backing-file' specified,"
3404                              " but 'top' is the active layer");
3405             goto out;
3406         }
3407         commit_active_start(has_job_id ? job_id : NULL, bs, base_bs,
3408                             JOB_DEFAULT, speed, on_error,
3409                             filter_node_name, NULL, NULL, false, &local_err);
3410     } else {
3411         BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
3412         if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
3413             goto out;
3414         }
3415         commit_start(has_job_id ? job_id : NULL, bs, base_bs, top_bs, speed,
3416                      on_error, has_backing_file ? backing_file : NULL,
3417                      filter_node_name, &local_err);
3418     }
3419     if (local_err != NULL) {
3420         error_propagate(errp, local_err);
3421         goto out;
3422     }
3423 
3424 out:
3425     aio_context_release(aio_context);
3426 }
3427 
3428 static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
3429                                  Error **errp)
3430 {
3431     BlockDriverState *bs;
3432     BlockDriverState *target_bs;
3433     BlockDriverState *source = NULL;
3434     BlockJob *job = NULL;
3435     BdrvDirtyBitmap *bmap = NULL;
3436     AioContext *aio_context;
3437     QDict *options = NULL;
3438     Error *local_err = NULL;
3439     int flags, job_flags = JOB_DEFAULT;
3440     int64_t size;
3441     bool set_backing_hd = false;
3442 
3443     if (!backup->has_speed) {
3444         backup->speed = 0;
3445     }
3446     if (!backup->has_on_source_error) {
3447         backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
3448     }
3449     if (!backup->has_on_target_error) {
3450         backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
3451     }
3452     if (!backup->has_mode) {
3453         backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
3454     }
3455     if (!backup->has_job_id) {
3456         backup->job_id = NULL;
3457     }
3458     if (!backup->has_auto_finalize) {
3459         backup->auto_finalize = true;
3460     }
3461     if (!backup->has_auto_dismiss) {
3462         backup->auto_dismiss = true;
3463     }
3464     if (!backup->has_compress) {
3465         backup->compress = false;
3466     }
3467 
3468     bs = qmp_get_root_bs(backup->device, errp);
3469     if (!bs) {
3470         return NULL;
3471     }
3472 
3473     aio_context = bdrv_get_aio_context(bs);
3474     aio_context_acquire(aio_context);
3475 
3476     if (!backup->has_format) {
3477         backup->format = backup->mode == NEW_IMAGE_MODE_EXISTING ?
3478                          NULL : (char*) bs->drv->format_name;
3479     }
3480 
3481     /* Early check to avoid creating target */
3482     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
3483         goto out;
3484     }
3485 
3486     flags = bs->open_flags | BDRV_O_RDWR;
3487 
3488     /* See if we have a backing HD we can use to create our new image
3489      * on top of. */
3490     if (backup->sync == MIRROR_SYNC_MODE_TOP) {
3491         source = backing_bs(bs);
3492         if (!source) {
3493             backup->sync = MIRROR_SYNC_MODE_FULL;
3494         }
3495     }
3496     if (backup->sync == MIRROR_SYNC_MODE_NONE) {
3497         source = bs;
3498         flags |= BDRV_O_NO_BACKING;
3499         set_backing_hd = true;
3500     }
3501 
3502     size = bdrv_getlength(bs);
3503     if (size < 0) {
3504         error_setg_errno(errp, -size, "bdrv_getlength failed");
3505         goto out;
3506     }
3507 
3508     if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
3509         assert(backup->format);
3510         if (source) {
3511             bdrv_img_create(backup->target, backup->format, source->filename,
3512                             source->drv->format_name, NULL,
3513                             size, flags, false, &local_err);
3514         } else {
3515             bdrv_img_create(backup->target, backup->format, NULL, NULL, NULL,
3516                             size, flags, false, &local_err);
3517         }
3518     }
3519 
3520     if (local_err) {
3521         error_propagate(errp, local_err);
3522         goto out;
3523     }
3524 
3525     if (backup->format) {
3526         if (!options) {
3527             options = qdict_new();
3528         }
3529         qdict_put_str(options, "driver", backup->format);
3530     }
3531 
3532     target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
3533     if (!target_bs) {
3534         goto out;
3535     }
3536 
3537     bdrv_set_aio_context(target_bs, aio_context);
3538 
3539     if (set_backing_hd) {
3540         bdrv_set_backing_hd(target_bs, source, &local_err);
3541         if (local_err) {
3542             bdrv_unref(target_bs);
3543             goto out;
3544         }
3545     }
3546 
3547     if (backup->has_bitmap) {
3548         bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
3549         if (!bmap) {
3550             error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
3551             bdrv_unref(target_bs);
3552             goto out;
3553         }
3554         if (bdrv_dirty_bitmap_qmp_locked(bmap)) {
3555             error_setg(errp,
3556                        "Bitmap '%s' is currently locked and cannot be used for "
3557                        "backup", backup->bitmap);
3558             goto out;
3559         }
3560     }
3561     if (!backup->auto_finalize) {
3562         job_flags |= JOB_MANUAL_FINALIZE;
3563     }
3564     if (!backup->auto_dismiss) {
3565         job_flags |= JOB_MANUAL_DISMISS;
3566     }
3567 
3568     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
3569                             backup->sync, bmap, backup->compress,
3570                             backup->on_source_error, backup->on_target_error,
3571                             job_flags, NULL, NULL, txn, &local_err);
3572     bdrv_unref(target_bs);
3573     if (local_err != NULL) {
3574         error_propagate(errp, local_err);
3575         goto out;
3576     }
3577 
3578 out:
3579     aio_context_release(aio_context);
3580     return job;
3581 }
3582 
3583 void qmp_drive_backup(DriveBackup *arg, Error **errp)
3584 {
3585 
3586     BlockJob *job;
3587     job = do_drive_backup(arg, NULL, errp);
3588     if (job) {
3589         job_start(&job->job);
3590     }
3591 }
3592 
3593 BlockDeviceInfoList *qmp_query_named_block_nodes(Error **errp)
3594 {
3595     return bdrv_named_nodes_list(errp);
3596 }
3597 
3598 BlockJob *do_blockdev_backup(BlockdevBackup *backup, JobTxn *txn,
3599                              Error **errp)
3600 {
3601     BlockDriverState *bs;
3602     BlockDriverState *target_bs;
3603     Error *local_err = NULL;
3604     AioContext *aio_context;
3605     BlockJob *job = NULL;
3606     int job_flags = JOB_DEFAULT;
3607 
3608     if (!backup->has_speed) {
3609         backup->speed = 0;
3610     }
3611     if (!backup->has_on_source_error) {
3612         backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
3613     }
3614     if (!backup->has_on_target_error) {
3615         backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
3616     }
3617     if (!backup->has_job_id) {
3618         backup->job_id = NULL;
3619     }
3620     if (!backup->has_auto_finalize) {
3621         backup->auto_finalize = true;
3622     }
3623     if (!backup->has_auto_dismiss) {
3624         backup->auto_dismiss = true;
3625     }
3626     if (!backup->has_compress) {
3627         backup->compress = false;
3628     }
3629 
3630     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
3631     if (!bs) {
3632         return NULL;
3633     }
3634 
3635     aio_context = bdrv_get_aio_context(bs);
3636     aio_context_acquire(aio_context);
3637 
3638     target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
3639     if (!target_bs) {
3640         goto out;
3641     }
3642 
3643     if (bdrv_get_aio_context(target_bs) != aio_context) {
3644         if (!bdrv_has_blk(target_bs)) {
3645             /* The target BDS is not attached, we can safely move it to another
3646              * AioContext. */
3647             bdrv_set_aio_context(target_bs, aio_context);
3648         } else {
3649             error_setg(errp, "Target is attached to a different thread from "
3650                              "source.");
3651             goto out;
3652         }
3653     }
3654     if (!backup->auto_finalize) {
3655         job_flags |= JOB_MANUAL_FINALIZE;
3656     }
3657     if (!backup->auto_dismiss) {
3658         job_flags |= JOB_MANUAL_DISMISS;
3659     }
3660     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
3661                             backup->sync, NULL, backup->compress,
3662                             backup->on_source_error, backup->on_target_error,
3663                             job_flags, NULL, NULL, txn, &local_err);
3664     if (local_err != NULL) {
3665         error_propagate(errp, local_err);
3666     }
3667 out:
3668     aio_context_release(aio_context);
3669     return job;
3670 }
3671 
3672 void qmp_blockdev_backup(BlockdevBackup *arg, Error **errp)
3673 {
3674     BlockJob *job;
3675     job = do_blockdev_backup(arg, NULL, errp);
3676     if (job) {
3677         job_start(&job->job);
3678     }
3679 }
3680 
3681 /* Parameter check and block job starting for drive mirroring.
3682  * Caller should hold @device and @target's aio context (must be the same).
3683  **/
3684 static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
3685                                    BlockDriverState *target,
3686                                    bool has_replaces, const char *replaces,
3687                                    enum MirrorSyncMode sync,
3688                                    BlockMirrorBackingMode backing_mode,
3689                                    bool has_speed, int64_t speed,
3690                                    bool has_granularity, uint32_t granularity,
3691                                    bool has_buf_size, int64_t buf_size,
3692                                    bool has_on_source_error,
3693                                    BlockdevOnError on_source_error,
3694                                    bool has_on_target_error,
3695                                    BlockdevOnError on_target_error,
3696                                    bool has_unmap, bool unmap,
3697                                    bool has_filter_node_name,
3698                                    const char *filter_node_name,
3699                                    bool has_copy_mode, MirrorCopyMode copy_mode,
3700                                    Error **errp)
3701 {
3702 
3703     if (!has_speed) {
3704         speed = 0;
3705     }
3706     if (!has_on_source_error) {
3707         on_source_error = BLOCKDEV_ON_ERROR_REPORT;
3708     }
3709     if (!has_on_target_error) {
3710         on_target_error = BLOCKDEV_ON_ERROR_REPORT;
3711     }
3712     if (!has_granularity) {
3713         granularity = 0;
3714     }
3715     if (!has_buf_size) {
3716         buf_size = 0;
3717     }
3718     if (!has_unmap) {
3719         unmap = true;
3720     }
3721     if (!has_filter_node_name) {
3722         filter_node_name = NULL;
3723     }
3724     if (!has_copy_mode) {
3725         copy_mode = MIRROR_COPY_MODE_BACKGROUND;
3726     }
3727 
3728     if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
3729         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
3730                    "a value in range [512B, 64MB]");
3731         return;
3732     }
3733     if (granularity & (granularity - 1)) {
3734         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
3735                    "power of 2");
3736         return;
3737     }
3738 
3739     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
3740         return;
3741     }
3742     if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
3743         return;
3744     }
3745 
3746     if (!bs->backing && sync == MIRROR_SYNC_MODE_TOP) {
3747         sync = MIRROR_SYNC_MODE_FULL;
3748     }
3749 
3750     /* pass the node name to replace to mirror start since it's loose coupling
3751      * and will allow to check whether the node still exist at mirror completion
3752      */
3753     mirror_start(job_id, bs, target,
3754                  has_replaces ? replaces : NULL,
3755                  speed, granularity, buf_size, sync, backing_mode,
3756                  on_source_error, on_target_error, unmap, filter_node_name,
3757                  copy_mode, errp);
3758 }
3759 
3760 void qmp_drive_mirror(DriveMirror *arg, Error **errp)
3761 {
3762     BlockDriverState *bs;
3763     BlockDriverState *source, *target_bs;
3764     AioContext *aio_context;
3765     BlockMirrorBackingMode backing_mode;
3766     Error *local_err = NULL;
3767     QDict *options = NULL;
3768     int flags;
3769     int64_t size;
3770     const char *format = arg->format;
3771 
3772     bs = qmp_get_root_bs(arg->device, errp);
3773     if (!bs) {
3774         return;
3775     }
3776 
3777     /* Early check to avoid creating target */
3778     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
3779         return;
3780     }
3781 
3782     aio_context = bdrv_get_aio_context(bs);
3783     aio_context_acquire(aio_context);
3784 
3785     if (!arg->has_mode) {
3786         arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
3787     }
3788 
3789     if (!arg->has_format) {
3790         format = (arg->mode == NEW_IMAGE_MODE_EXISTING
3791                   ? NULL : bs->drv->format_name);
3792     }
3793 
3794     flags = bs->open_flags | BDRV_O_RDWR;
3795     source = backing_bs(bs);
3796     if (!source && arg->sync == MIRROR_SYNC_MODE_TOP) {
3797         arg->sync = MIRROR_SYNC_MODE_FULL;
3798     }
3799     if (arg->sync == MIRROR_SYNC_MODE_NONE) {
3800         source = bs;
3801     }
3802 
3803     size = bdrv_getlength(bs);
3804     if (size < 0) {
3805         error_setg_errno(errp, -size, "bdrv_getlength failed");
3806         goto out;
3807     }
3808 
3809     if (arg->has_replaces) {
3810         BlockDriverState *to_replace_bs;
3811         AioContext *replace_aio_context;
3812         int64_t replace_size;
3813 
3814         if (!arg->has_node_name) {
3815             error_setg(errp, "a node-name must be provided when replacing a"
3816                              " named node of the graph");
3817             goto out;
3818         }
3819 
3820         to_replace_bs = check_to_replace_node(bs, arg->replaces, &local_err);
3821 
3822         if (!to_replace_bs) {
3823             error_propagate(errp, local_err);
3824             goto out;
3825         }
3826 
3827         replace_aio_context = bdrv_get_aio_context(to_replace_bs);
3828         aio_context_acquire(replace_aio_context);
3829         replace_size = bdrv_getlength(to_replace_bs);
3830         aio_context_release(replace_aio_context);
3831 
3832         if (size != replace_size) {
3833             error_setg(errp, "cannot replace image with a mirror image of "
3834                              "different size");
3835             goto out;
3836         }
3837     }
3838 
3839     if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
3840         backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
3841     } else {
3842         backing_mode = MIRROR_OPEN_BACKING_CHAIN;
3843     }
3844 
3845     /* Don't open backing image in create() */
3846     flags |= BDRV_O_NO_BACKING;
3847 
3848     if ((arg->sync == MIRROR_SYNC_MODE_FULL || !source)
3849         && arg->mode != NEW_IMAGE_MODE_EXISTING)
3850     {
3851         /* create new image w/o backing file */
3852         assert(format);
3853         bdrv_img_create(arg->target, format,
3854                         NULL, NULL, NULL, size, flags, false, &local_err);
3855     } else {
3856         switch (arg->mode) {
3857         case NEW_IMAGE_MODE_EXISTING:
3858             break;
3859         case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
3860             /* create new image with backing file */
3861             bdrv_img_create(arg->target, format,
3862                             source->filename,
3863                             source->drv->format_name,
3864                             NULL, size, flags, false, &local_err);
3865             break;
3866         default:
3867             abort();
3868         }
3869     }
3870 
3871     if (local_err) {
3872         error_propagate(errp, local_err);
3873         goto out;
3874     }
3875 
3876     options = qdict_new();
3877     if (arg->has_node_name) {
3878         qdict_put_str(options, "node-name", arg->node_name);
3879     }
3880     if (format) {
3881         qdict_put_str(options, "driver", format);
3882     }
3883 
3884     /* Mirroring takes care of copy-on-write using the source's backing
3885      * file.
3886      */
3887     target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
3888     if (!target_bs) {
3889         goto out;
3890     }
3891 
3892     bdrv_set_aio_context(target_bs, aio_context);
3893 
3894     blockdev_mirror_common(arg->has_job_id ? arg->job_id : NULL, bs, target_bs,
3895                            arg->has_replaces, arg->replaces, arg->sync,
3896                            backing_mode, arg->has_speed, arg->speed,
3897                            arg->has_granularity, arg->granularity,
3898                            arg->has_buf_size, arg->buf_size,
3899                            arg->has_on_source_error, arg->on_source_error,
3900                            arg->has_on_target_error, arg->on_target_error,
3901                            arg->has_unmap, arg->unmap,
3902                            false, NULL,
3903                            arg->has_copy_mode, arg->copy_mode,
3904                            &local_err);
3905     bdrv_unref(target_bs);
3906     error_propagate(errp, local_err);
3907 out:
3908     aio_context_release(aio_context);
3909 }
3910 
3911 void qmp_blockdev_mirror(bool has_job_id, const char *job_id,
3912                          const char *device, const char *target,
3913                          bool has_replaces, const char *replaces,
3914                          MirrorSyncMode sync,
3915                          bool has_speed, int64_t speed,
3916                          bool has_granularity, uint32_t granularity,
3917                          bool has_buf_size, int64_t buf_size,
3918                          bool has_on_source_error,
3919                          BlockdevOnError on_source_error,
3920                          bool has_on_target_error,
3921                          BlockdevOnError on_target_error,
3922                          bool has_filter_node_name,
3923                          const char *filter_node_name,
3924                          bool has_copy_mode, MirrorCopyMode copy_mode,
3925                          Error **errp)
3926 {
3927     BlockDriverState *bs;
3928     BlockDriverState *target_bs;
3929     AioContext *aio_context;
3930     BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
3931     Error *local_err = NULL;
3932 
3933     bs = qmp_get_root_bs(device, errp);
3934     if (!bs) {
3935         return;
3936     }
3937 
3938     target_bs = bdrv_lookup_bs(target, target, errp);
3939     if (!target_bs) {
3940         return;
3941     }
3942 
3943     aio_context = bdrv_get_aio_context(bs);
3944     aio_context_acquire(aio_context);
3945 
3946     bdrv_set_aio_context(target_bs, aio_context);
3947 
3948     blockdev_mirror_common(has_job_id ? job_id : NULL, bs, target_bs,
3949                            has_replaces, replaces, sync, backing_mode,
3950                            has_speed, speed,
3951                            has_granularity, granularity,
3952                            has_buf_size, buf_size,
3953                            has_on_source_error, on_source_error,
3954                            has_on_target_error, on_target_error,
3955                            true, true,
3956                            has_filter_node_name, filter_node_name,
3957                            has_copy_mode, copy_mode,
3958                            &local_err);
3959     error_propagate(errp, local_err);
3960 
3961     aio_context_release(aio_context);
3962 }
3963 
3964 /* Get a block job using its ID and acquire its AioContext */
3965 static BlockJob *find_block_job(const char *id, AioContext **aio_context,
3966                                 Error **errp)
3967 {
3968     BlockJob *job;
3969 
3970     assert(id != NULL);
3971 
3972     *aio_context = NULL;
3973 
3974     job = block_job_get(id);
3975 
3976     if (!job) {
3977         error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
3978                   "Block job '%s' not found", id);
3979         return NULL;
3980     }
3981 
3982     *aio_context = blk_get_aio_context(job->blk);
3983     aio_context_acquire(*aio_context);
3984 
3985     return job;
3986 }
3987 
3988 void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
3989 {
3990     AioContext *aio_context;
3991     BlockJob *job = find_block_job(device, &aio_context, errp);
3992 
3993     if (!job) {
3994         return;
3995     }
3996 
3997     block_job_set_speed(job, speed, errp);
3998     aio_context_release(aio_context);
3999 }
4000 
4001 void qmp_block_job_cancel(const char *device,
4002                           bool has_force, bool force, Error **errp)
4003 {
4004     AioContext *aio_context;
4005     BlockJob *job = find_block_job(device, &aio_context, errp);
4006 
4007     if (!job) {
4008         return;
4009     }
4010 
4011     if (!has_force) {
4012         force = false;
4013     }
4014 
4015     if (job_user_paused(&job->job) && !force) {
4016         error_setg(errp, "The block job for device '%s' is currently paused",
4017                    device);
4018         goto out;
4019     }
4020 
4021     trace_qmp_block_job_cancel(job);
4022     job_user_cancel(&job->job, force, errp);
4023 out:
4024     aio_context_release(aio_context);
4025 }
4026 
4027 void qmp_block_job_pause(const char *device, Error **errp)
4028 {
4029     AioContext *aio_context;
4030     BlockJob *job = find_block_job(device, &aio_context, errp);
4031 
4032     if (!job) {
4033         return;
4034     }
4035 
4036     trace_qmp_block_job_pause(job);
4037     job_user_pause(&job->job, errp);
4038     aio_context_release(aio_context);
4039 }
4040 
4041 void qmp_block_job_resume(const char *device, Error **errp)
4042 {
4043     AioContext *aio_context;
4044     BlockJob *job = find_block_job(device, &aio_context, errp);
4045 
4046     if (!job) {
4047         return;
4048     }
4049 
4050     trace_qmp_block_job_resume(job);
4051     job_user_resume(&job->job, errp);
4052     aio_context_release(aio_context);
4053 }
4054 
4055 void qmp_block_job_complete(const char *device, Error **errp)
4056 {
4057     AioContext *aio_context;
4058     BlockJob *job = find_block_job(device, &aio_context, errp);
4059 
4060     if (!job) {
4061         return;
4062     }
4063 
4064     trace_qmp_block_job_complete(job);
4065     job_complete(&job->job, errp);
4066     aio_context_release(aio_context);
4067 }
4068 
4069 void qmp_block_job_finalize(const char *id, Error **errp)
4070 {
4071     AioContext *aio_context;
4072     BlockJob *job = find_block_job(id, &aio_context, errp);
4073 
4074     if (!job) {
4075         return;
4076     }
4077 
4078     trace_qmp_block_job_finalize(job);
4079     job_finalize(&job->job, errp);
4080     aio_context_release(aio_context);
4081 }
4082 
4083 void qmp_block_job_dismiss(const char *id, Error **errp)
4084 {
4085     AioContext *aio_context;
4086     BlockJob *bjob = find_block_job(id, &aio_context, errp);
4087     Job *job;
4088 
4089     if (!bjob) {
4090         return;
4091     }
4092 
4093     trace_qmp_block_job_dismiss(bjob);
4094     job = &bjob->job;
4095     job_dismiss(&job, errp);
4096     aio_context_release(aio_context);
4097 }
4098 
4099 void qmp_change_backing_file(const char *device,
4100                              const char *image_node_name,
4101                              const char *backing_file,
4102                              Error **errp)
4103 {
4104     BlockDriverState *bs = NULL;
4105     AioContext *aio_context;
4106     BlockDriverState *image_bs = NULL;
4107     Error *local_err = NULL;
4108     bool ro;
4109     int open_flags;
4110     int ret;
4111 
4112     bs = qmp_get_root_bs(device, errp);
4113     if (!bs) {
4114         return;
4115     }
4116 
4117     aio_context = bdrv_get_aio_context(bs);
4118     aio_context_acquire(aio_context);
4119 
4120     image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
4121     if (local_err) {
4122         error_propagate(errp, local_err);
4123         goto out;
4124     }
4125 
4126     if (!image_bs) {
4127         error_setg(errp, "image file not found");
4128         goto out;
4129     }
4130 
4131     if (bdrv_find_base(image_bs) == image_bs) {
4132         error_setg(errp, "not allowing backing file change on an image "
4133                          "without a backing file");
4134         goto out;
4135     }
4136 
4137     /* even though we are not necessarily operating on bs, we need it to
4138      * determine if block ops are currently prohibited on the chain */
4139     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
4140         goto out;
4141     }
4142 
4143     /* final sanity check */
4144     if (!bdrv_chain_contains(bs, image_bs)) {
4145         error_setg(errp, "'%s' and image file are not in the same chain",
4146                    device);
4147         goto out;
4148     }
4149 
4150     /* if not r/w, reopen to make r/w */
4151     open_flags = image_bs->open_flags;
4152     ro = bdrv_is_read_only(image_bs);
4153 
4154     if (ro) {
4155         bdrv_reopen(image_bs, open_flags | BDRV_O_RDWR, &local_err);
4156         if (local_err) {
4157             error_propagate(errp, local_err);
4158             goto out;
4159         }
4160     }
4161 
4162     ret = bdrv_change_backing_file(image_bs, backing_file,
4163                                image_bs->drv ? image_bs->drv->format_name : "");
4164 
4165     if (ret < 0) {
4166         error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
4167                          backing_file);
4168         /* don't exit here, so we can try to restore open flags if
4169          * appropriate */
4170     }
4171 
4172     if (ro) {
4173         bdrv_reopen(image_bs, open_flags, &local_err);
4174         error_propagate(errp, local_err);
4175     }
4176 
4177 out:
4178     aio_context_release(aio_context);
4179 }
4180 
4181 void hmp_drive_add_node(Monitor *mon, const char *optstr)
4182 {
4183     QemuOpts *opts;
4184     QDict *qdict;
4185     Error *local_err = NULL;
4186 
4187     opts = qemu_opts_parse_noisily(&qemu_drive_opts, optstr, false);
4188     if (!opts) {
4189         return;
4190     }
4191 
4192     qdict = qemu_opts_to_qdict(opts, NULL);
4193 
4194     if (!qdict_get_try_str(qdict, "node-name")) {
4195         qobject_unref(qdict);
4196         error_report("'node-name' needs to be specified");
4197         goto out;
4198     }
4199 
4200     BlockDriverState *bs = bds_tree_init(qdict, &local_err);
4201     if (!bs) {
4202         error_report_err(local_err);
4203         goto out;
4204     }
4205 
4206     QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
4207 
4208 out:
4209     qemu_opts_del(opts);
4210 }
4211 
4212 void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
4213 {
4214     BlockDriverState *bs;
4215     QObject *obj;
4216     Visitor *v = qobject_output_visitor_new(&obj);
4217     QDict *qdict;
4218     Error *local_err = NULL;
4219 
4220     visit_type_BlockdevOptions(v, NULL, &options, &local_err);
4221     if (local_err) {
4222         error_propagate(errp, local_err);
4223         goto fail;
4224     }
4225 
4226     visit_complete(v, &obj);
4227     qdict = qobject_to(QDict, obj);
4228 
4229     qdict_flatten(qdict);
4230 
4231     if (!qdict_get_try_str(qdict, "node-name")) {
4232         error_setg(errp, "'node-name' must be specified for the root node");
4233         goto fail;
4234     }
4235 
4236     bs = bds_tree_init(qdict, errp);
4237     if (!bs) {
4238         goto fail;
4239     }
4240 
4241     QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
4242 
4243 fail:
4244     visit_free(v);
4245 }
4246 
4247 void qmp_blockdev_del(const char *node_name, Error **errp)
4248 {
4249     AioContext *aio_context;
4250     BlockDriverState *bs;
4251 
4252     bs = bdrv_find_node(node_name);
4253     if (!bs) {
4254         error_setg(errp, "Cannot find node %s", node_name);
4255         return;
4256     }
4257     if (bdrv_has_blk(bs)) {
4258         error_setg(errp, "Node %s is in use", node_name);
4259         return;
4260     }
4261     aio_context = bdrv_get_aio_context(bs);
4262     aio_context_acquire(aio_context);
4263 
4264     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
4265         goto out;
4266     }
4267 
4268     if (!bs->monitor_list.tqe_prev) {
4269         error_setg(errp, "Node %s is not owned by the monitor",
4270                    bs->node_name);
4271         goto out;
4272     }
4273 
4274     if (bs->refcnt > 1) {
4275         error_setg(errp, "Block device %s is in use",
4276                    bdrv_get_device_or_node_name(bs));
4277         goto out;
4278     }
4279 
4280     QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
4281     bdrv_unref(bs);
4282 
4283 out:
4284     aio_context_release(aio_context);
4285 }
4286 
4287 static BdrvChild *bdrv_find_child(BlockDriverState *parent_bs,
4288                                   const char *child_name)
4289 {
4290     BdrvChild *child;
4291 
4292     QLIST_FOREACH(child, &parent_bs->children, next) {
4293         if (strcmp(child->name, child_name) == 0) {
4294             return child;
4295         }
4296     }
4297 
4298     return NULL;
4299 }
4300 
4301 void qmp_x_blockdev_change(const char *parent, bool has_child,
4302                            const char *child, bool has_node,
4303                            const char *node, Error **errp)
4304 {
4305     BlockDriverState *parent_bs, *new_bs = NULL;
4306     BdrvChild *p_child;
4307 
4308     parent_bs = bdrv_lookup_bs(parent, parent, errp);
4309     if (!parent_bs) {
4310         return;
4311     }
4312 
4313     if (has_child == has_node) {
4314         if (has_child) {
4315             error_setg(errp, "The parameters child and node are in conflict");
4316         } else {
4317             error_setg(errp, "Either child or node must be specified");
4318         }
4319         return;
4320     }
4321 
4322     if (has_child) {
4323         p_child = bdrv_find_child(parent_bs, child);
4324         if (!p_child) {
4325             error_setg(errp, "Node '%s' does not have child '%s'",
4326                        parent, child);
4327             return;
4328         }
4329         bdrv_del_child(parent_bs, p_child, errp);
4330     }
4331 
4332     if (has_node) {
4333         new_bs = bdrv_find_node(node);
4334         if (!new_bs) {
4335             error_setg(errp, "Node '%s' not found", node);
4336             return;
4337         }
4338         bdrv_add_child(parent_bs, new_bs, errp);
4339     }
4340 }
4341 
4342 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
4343 {
4344     BlockJobInfoList *head = NULL, **p_next = &head;
4345     BlockJob *job;
4346 
4347     for (job = block_job_next(NULL); job; job = block_job_next(job)) {
4348         BlockJobInfoList *elem;
4349         AioContext *aio_context;
4350 
4351         if (block_job_is_internal(job)) {
4352             continue;
4353         }
4354         elem = g_new0(BlockJobInfoList, 1);
4355         aio_context = blk_get_aio_context(job->blk);
4356         aio_context_acquire(aio_context);
4357         elem->value = block_job_query(job, errp);
4358         aio_context_release(aio_context);
4359         if (!elem->value) {
4360             g_free(elem);
4361             qapi_free_BlockJobInfoList(head);
4362             return NULL;
4363         }
4364         *p_next = elem;
4365         p_next = &elem->next;
4366     }
4367 
4368     return head;
4369 }
4370 
4371 void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
4372                                  bool has_force, bool force, Error **errp)
4373 {
4374     AioContext *old_context;
4375     AioContext *new_context;
4376     BlockDriverState *bs;
4377 
4378     bs = bdrv_find_node(node_name);
4379     if (!bs) {
4380         error_setg(errp, "Cannot find node %s", node_name);
4381         return;
4382     }
4383 
4384     /* Protects against accidents. */
4385     if (!(has_force && force) && bdrv_has_blk(bs)) {
4386         error_setg(errp, "Node %s is associated with a BlockBackend and could "
4387                          "be in use (use force=true to override this check)",
4388                          node_name);
4389         return;
4390     }
4391 
4392     if (iothread->type == QTYPE_QSTRING) {
4393         IOThread *obj = iothread_by_id(iothread->u.s);
4394         if (!obj) {
4395             error_setg(errp, "Cannot find iothread %s", iothread->u.s);
4396             return;
4397         }
4398 
4399         new_context = iothread_get_aio_context(obj);
4400     } else {
4401         new_context = qemu_get_aio_context();
4402     }
4403 
4404     old_context = bdrv_get_aio_context(bs);
4405     aio_context_acquire(old_context);
4406 
4407     bdrv_set_aio_context(bs, new_context);
4408 
4409     aio_context_release(old_context);
4410 }
4411 
4412 void qmp_x_block_latency_histogram_set(
4413     const char *device,
4414     bool has_boundaries, uint64List *boundaries,
4415     bool has_boundaries_read, uint64List *boundaries_read,
4416     bool has_boundaries_write, uint64List *boundaries_write,
4417     bool has_boundaries_flush, uint64List *boundaries_flush,
4418     Error **errp)
4419 {
4420     BlockBackend *blk = blk_by_name(device);
4421     BlockAcctStats *stats;
4422 
4423     if (!blk) {
4424         error_setg(errp, "Device '%s' not found", device);
4425         return;
4426     }
4427     stats = blk_get_stats(blk);
4428 
4429     if (!has_boundaries && !has_boundaries_read && !has_boundaries_write &&
4430         !has_boundaries_flush)
4431     {
4432         block_latency_histograms_clear(stats);
4433         return;
4434     }
4435 
4436     if (has_boundaries || has_boundaries_read) {
4437         block_latency_histogram_set(
4438             stats, BLOCK_ACCT_READ,
4439             has_boundaries_read ? boundaries_read : boundaries);
4440     }
4441 
4442     if (has_boundaries || has_boundaries_write) {
4443         block_latency_histogram_set(
4444             stats, BLOCK_ACCT_WRITE,
4445             has_boundaries_write ? boundaries_write : boundaries);
4446     }
4447 
4448     if (has_boundaries || has_boundaries_flush) {
4449         block_latency_histogram_set(
4450             stats, BLOCK_ACCT_FLUSH,
4451             has_boundaries_flush ? boundaries_flush : boundaries);
4452     }
4453 }
4454 
4455 QemuOptsList qemu_common_drive_opts = {
4456     .name = "drive",
4457     .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
4458     .desc = {
4459         {
4460             .name = "snapshot",
4461             .type = QEMU_OPT_BOOL,
4462             .help = "enable/disable snapshot mode",
4463         },{
4464             .name = "aio",
4465             .type = QEMU_OPT_STRING,
4466             .help = "host AIO implementation (threads, native)",
4467         },{
4468             .name = BDRV_OPT_CACHE_WB,
4469             .type = QEMU_OPT_BOOL,
4470             .help = "Enable writeback mode",
4471         },{
4472             .name = "format",
4473             .type = QEMU_OPT_STRING,
4474             .help = "disk format (raw, qcow2, ...)",
4475         },{
4476             .name = "rerror",
4477             .type = QEMU_OPT_STRING,
4478             .help = "read error action",
4479         },{
4480             .name = "werror",
4481             .type = QEMU_OPT_STRING,
4482             .help = "write error action",
4483         },{
4484             .name = BDRV_OPT_READ_ONLY,
4485             .type = QEMU_OPT_BOOL,
4486             .help = "open drive file as read-only",
4487         },
4488 
4489         THROTTLE_OPTS,
4490 
4491         {
4492             .name = "throttling.group",
4493             .type = QEMU_OPT_STRING,
4494             .help = "name of the block throttling group",
4495         },{
4496             .name = "copy-on-read",
4497             .type = QEMU_OPT_BOOL,
4498             .help = "copy read data from backing file into image file",
4499         },{
4500             .name = "detect-zeroes",
4501             .type = QEMU_OPT_STRING,
4502             .help = "try to optimize zero writes (off, on, unmap)",
4503         },{
4504             .name = "stats-account-invalid",
4505             .type = QEMU_OPT_BOOL,
4506             .help = "whether to account for invalid I/O operations "
4507                     "in the statistics",
4508         },{
4509             .name = "stats-account-failed",
4510             .type = QEMU_OPT_BOOL,
4511             .help = "whether to account for failed I/O operations "
4512                     "in the statistics",
4513         },
4514         { /* end of list */ }
4515     },
4516 };
4517 
4518 QemuOptsList qemu_drive_opts = {
4519     .name = "drive",
4520     .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
4521     .desc = {
4522         /*
4523          * no elements => accept any params
4524          * validation will happen later
4525          */
4526         { /* end of list */ }
4527     },
4528 };
4529