xref: /qemu/blockdev.c (revision 83c2201fc47bd0dfa656bde7202bd0e2539d54a0)
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 "system/block-backend.h"
35 #include "system/blockdev.h"
36 #include "hw/block/block.h"
37 #include "block/blockjob.h"
38 #include "block/dirty-bitmap.h"
39 #include "block/qdict.h"
40 #include "block/throttle-groups.h"
41 #include "monitor/monitor.h"
42 #include "qemu/error-report.h"
43 #include "qemu/option.h"
44 #include "qemu/qemu-print.h"
45 #include "qemu/config-file.h"
46 #include "qapi/qapi-commands-block.h"
47 #include "qapi/qapi-commands-transaction.h"
48 #include "qapi/qapi-visit-block-core.h"
49 #include "qobject/qdict.h"
50 #include "qobject/qnum.h"
51 #include "qobject/qstring.h"
52 #include "qapi/error.h"
53 #include "qapi/qmp/qerror.h"
54 #include "qobject/qlist.h"
55 #include "qapi/qobject-output-visitor.h"
56 #include "system/system.h"
57 #include "system/iothread.h"
58 #include "block/block_int.h"
59 #include "block/trace.h"
60 #include "system/runstate.h"
61 #include "system/replay.h"
62 #include "qemu/cutils.h"
63 #include "qemu/help_option.h"
64 #include "qemu/main-loop.h"
65 #include "qemu/throttle-options.h"
66 
67 /* Protected by BQL */
68 QTAILQ_HEAD(, BlockDriverState) monitor_bdrv_states =
69     QTAILQ_HEAD_INITIALIZER(monitor_bdrv_states);
70 
bdrv_set_monitor_owned(BlockDriverState * bs)71 void bdrv_set_monitor_owned(BlockDriverState *bs)
72 {
73     GLOBAL_STATE_CODE();
74     QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
75 }
76 
77 static const char *const if_name[IF_COUNT] = {
78     [IF_NONE] = "none",
79     [IF_IDE] = "ide",
80     [IF_SCSI] = "scsi",
81     [IF_FLOPPY] = "floppy",
82     [IF_PFLASH] = "pflash",
83     [IF_MTD] = "mtd",
84     [IF_SD] = "sd",
85     [IF_VIRTIO] = "virtio",
86     [IF_XEN] = "xen",
87 };
88 
89 static int if_max_devs[IF_COUNT] = {
90     /*
91      * Do not change these numbers!  They govern how drive option
92      * index maps to unit and bus.  That mapping is ABI.
93      *
94      * All controllers used to implement if=T drives need to support
95      * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
96      * Otherwise, some index values map to "impossible" bus, unit
97      * values.
98      *
99      * For instance, if you change [IF_SCSI] to 255, -drive
100      * if=scsi,index=12 no longer means bus=1,unit=5, but
101      * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
102      * the drive can't be set up.  Regression.
103      */
104     [IF_IDE] = 2,
105     [IF_SCSI] = 7,
106 };
107 
108 /**
109  * Boards may call this to offer board-by-board overrides
110  * of the default, global values.
111  */
override_max_devs(BlockInterfaceType type,int max_devs)112 void override_max_devs(BlockInterfaceType type, int max_devs)
113 {
114     BlockBackend *blk;
115     DriveInfo *dinfo;
116 
117     GLOBAL_STATE_CODE();
118 
119     if (max_devs <= 0) {
120         return;
121     }
122 
123     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
124         dinfo = blk_legacy_dinfo(blk);
125         if (dinfo->type == type) {
126             fprintf(stderr, "Cannot override units-per-bus property of"
127                     " the %s interface, because a drive of that type has"
128                     " already been added.\n", if_name[type]);
129             g_assert_not_reached();
130         }
131     }
132 
133     if_max_devs[type] = max_devs;
134 }
135 
136 /*
137  * We automatically delete the drive when a device using it gets
138  * unplugged.  Questionable feature, but we can't just drop it.
139  * Device models call blockdev_mark_auto_del() to schedule the
140  * automatic deletion, and generic qdev code calls blockdev_auto_del()
141  * when deletion is actually safe.
142  */
blockdev_mark_auto_del(BlockBackend * blk)143 void blockdev_mark_auto_del(BlockBackend *blk)
144 {
145     DriveInfo *dinfo = blk_legacy_dinfo(blk);
146     BlockJob *job;
147 
148     GLOBAL_STATE_CODE();
149 
150     if (!dinfo) {
151         return;
152     }
153 
154     JOB_LOCK_GUARD();
155 
156     do {
157         job = block_job_next_locked(NULL);
158         while (job && (job->job.cancelled ||
159                        job->job.deferred_to_main_loop ||
160                        !block_job_has_bdrv(job, blk_bs(blk))))
161         {
162             job = block_job_next_locked(job);
163         }
164         if (job) {
165             /*
166              * This drops the job lock temporarily and polls, so we need to
167              * restart processing the list from the start after this.
168              */
169             job_cancel_locked(&job->job, false);
170         }
171     } while (job);
172 
173     dinfo->auto_del = 1;
174 }
175 
blockdev_auto_del(BlockBackend * blk)176 void blockdev_auto_del(BlockBackend *blk)
177 {
178     DriveInfo *dinfo = blk_legacy_dinfo(blk);
179     GLOBAL_STATE_CODE();
180 
181     if (dinfo && dinfo->auto_del) {
182         monitor_remove_blk(blk);
183         blk_unref(blk);
184     }
185 }
186 
drive_index_to_bus_id(BlockInterfaceType type,int index)187 static int drive_index_to_bus_id(BlockInterfaceType type, int index)
188 {
189     int max_devs = if_max_devs[type];
190     return max_devs ? index / max_devs : 0;
191 }
192 
drive_index_to_unit_id(BlockInterfaceType type,int index)193 static int drive_index_to_unit_id(BlockInterfaceType type, int index)
194 {
195     int max_devs = if_max_devs[type];
196     return max_devs ? index % max_devs : index;
197 }
198 
drive_add(BlockInterfaceType type,int index,const char * file,const char * optstr)199 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
200                     const char *optstr)
201 {
202     QemuOpts *opts;
203 
204     GLOBAL_STATE_CODE();
205 
206     opts = qemu_opts_parse_noisily(qemu_find_opts("drive"), optstr, false);
207     if (!opts) {
208         return NULL;
209     }
210     if (type != IF_DEFAULT) {
211         qemu_opt_set(opts, "if", if_name[type], &error_abort);
212     }
213     if (index >= 0) {
214         qemu_opt_set_number(opts, "index", index, &error_abort);
215     }
216     if (file)
217         qemu_opt_set(opts, "file", file, &error_abort);
218     return opts;
219 }
220 
drive_get(BlockInterfaceType type,int bus,int unit)221 DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
222 {
223     BlockBackend *blk;
224     DriveInfo *dinfo;
225 
226     GLOBAL_STATE_CODE();
227 
228     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
229         dinfo = blk_legacy_dinfo(blk);
230         if (dinfo && dinfo->type == type
231             && dinfo->bus == bus && dinfo->unit == unit) {
232             return dinfo;
233         }
234     }
235 
236     return NULL;
237 }
238 
239 /*
240  * Check board claimed all -drive that are meant to be claimed.
241  * Fatal error if any remain unclaimed.
242  */
drive_check_orphaned(void)243 void drive_check_orphaned(void)
244 {
245     BlockBackend *blk;
246     DriveInfo *dinfo;
247     Location loc;
248     bool orphans = false;
249 
250     GLOBAL_STATE_CODE();
251 
252     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
253         dinfo = blk_legacy_dinfo(blk);
254         /*
255          * Ignore default drives, because we create certain default
256          * drives unconditionally, then leave them unclaimed.  Not the
257          * users fault.
258          * Ignore IF_VIRTIO or IF_XEN, because it gets desugared into
259          * -device, so we can leave failing to -device.
260          * Ignore IF_NONE, because leaving unclaimed IF_NONE remains
261          * available for device_add is a feature.
262          */
263         if (dinfo->is_default || dinfo->type == IF_VIRTIO
264             || dinfo->type == IF_XEN || dinfo->type == IF_NONE) {
265             continue;
266         }
267         if (!blk_get_attached_dev(blk)) {
268             loc_push_none(&loc);
269             qemu_opts_loc_restore(dinfo->opts);
270             error_report("machine type does not support"
271                          " if=%s,bus=%d,unit=%d",
272                          if_name[dinfo->type], dinfo->bus, dinfo->unit);
273             loc_pop(&loc);
274             orphans = true;
275         }
276     }
277 
278     if (orphans) {
279         exit(1);
280     }
281 }
282 
drive_get_by_index(BlockInterfaceType type,int index)283 DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
284 {
285     GLOBAL_STATE_CODE();
286     return drive_get(type,
287                      drive_index_to_bus_id(type, index),
288                      drive_index_to_unit_id(type, index));
289 }
290 
drive_get_max_bus(BlockInterfaceType type)291 int drive_get_max_bus(BlockInterfaceType type)
292 {
293     int max_bus;
294     BlockBackend *blk;
295     DriveInfo *dinfo;
296 
297     GLOBAL_STATE_CODE();
298 
299     max_bus = -1;
300     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
301         dinfo = blk_legacy_dinfo(blk);
302         if (dinfo && dinfo->type == type && dinfo->bus > max_bus) {
303             max_bus = dinfo->bus;
304         }
305     }
306     return max_bus;
307 }
308 
bdrv_format_print(void * opaque,const char * name)309 static void bdrv_format_print(void *opaque, const char *name)
310 {
311     qemu_printf(" %s", name);
312 }
313 
314 typedef struct {
315     QEMUBH *bh;
316     BlockDriverState *bs;
317 } BDRVPutRefBH;
318 
parse_block_error_action(const char * buf,bool is_read,Error ** errp)319 static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
320 {
321     if (!strcmp(buf, "ignore")) {
322         return BLOCKDEV_ON_ERROR_IGNORE;
323     } else if (!is_read && !strcmp(buf, "enospc")) {
324         return BLOCKDEV_ON_ERROR_ENOSPC;
325     } else if (!strcmp(buf, "stop")) {
326         return BLOCKDEV_ON_ERROR_STOP;
327     } else if (!strcmp(buf, "report")) {
328         return BLOCKDEV_ON_ERROR_REPORT;
329     } else {
330         error_setg(errp, "'%s' invalid %s error action",
331                    buf, is_read ? "read" : "write");
332         return -1;
333     }
334 }
335 
parse_stats_intervals(BlockAcctStats * stats,QList * intervals,Error ** errp)336 static bool parse_stats_intervals(BlockAcctStats *stats, QList *intervals,
337                                   Error **errp)
338 {
339     const QListEntry *entry;
340     for (entry = qlist_first(intervals); entry; entry = qlist_next(entry)) {
341         switch (qobject_type(entry->value)) {
342 
343         case QTYPE_QSTRING: {
344             uint64_t length;
345             const char *str = qstring_get_str(qobject_to(QString,
346                                                          entry->value));
347             if (parse_uint_full(str, 10, &length) == 0 &&
348                 length > 0 && length <= UINT_MAX) {
349                 block_acct_add_interval(stats, (unsigned) length);
350             } else {
351                 error_setg(errp, "Invalid interval length: %s", str);
352                 return false;
353             }
354             break;
355         }
356 
357         case QTYPE_QNUM: {
358             int64_t length = qnum_get_int(qobject_to(QNum, entry->value));
359 
360             if (length > 0 && length <= UINT_MAX) {
361                 block_acct_add_interval(stats, (unsigned) length);
362             } else {
363                 error_setg(errp, "Invalid interval length: %" PRId64, length);
364                 return false;
365             }
366             break;
367         }
368 
369         default:
370             error_setg(errp, "The specification of stats-intervals is invalid");
371             return false;
372         }
373     }
374     return true;
375 }
376 
377 typedef enum { MEDIA_DISK, MEDIA_CDROM } DriveMediaType;
378 
379 /* All parameters but @opts are optional and may be set to NULL. */
extract_common_blockdev_options(QemuOpts * opts,int * bdrv_flags,const char ** throttling_group,ThrottleConfig * throttle_cfg,BlockdevDetectZeroesOptions * detect_zeroes,Error ** errp)380 static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
381     const char **throttling_group, ThrottleConfig *throttle_cfg,
382     BlockdevDetectZeroesOptions *detect_zeroes, Error **errp)
383 {
384     Error *local_error = NULL;
385     const char *aio;
386 
387     if (bdrv_flags) {
388         if (qemu_opt_get_bool(opts, "copy-on-read", false)) {
389             *bdrv_flags |= BDRV_O_COPY_ON_READ;
390         }
391 
392         if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
393             if (bdrv_parse_aio(aio, bdrv_flags) < 0) {
394                 error_setg(errp, "invalid aio option");
395                 return;
396             }
397         }
398     }
399 
400     /* disk I/O throttling */
401     if (throttling_group) {
402         *throttling_group = qemu_opt_get(opts, "throttling.group");
403     }
404 
405     if (throttle_cfg) {
406         throttle_config_init(throttle_cfg);
407         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg =
408             qemu_opt_get_number(opts, "throttling.bps-total", 0);
409         throttle_cfg->buckets[THROTTLE_BPS_READ].avg  =
410             qemu_opt_get_number(opts, "throttling.bps-read", 0);
411         throttle_cfg->buckets[THROTTLE_BPS_WRITE].avg =
412             qemu_opt_get_number(opts, "throttling.bps-write", 0);
413         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].avg =
414             qemu_opt_get_number(opts, "throttling.iops-total", 0);
415         throttle_cfg->buckets[THROTTLE_OPS_READ].avg =
416             qemu_opt_get_number(opts, "throttling.iops-read", 0);
417         throttle_cfg->buckets[THROTTLE_OPS_WRITE].avg =
418             qemu_opt_get_number(opts, "throttling.iops-write", 0);
419 
420         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].max =
421             qemu_opt_get_number(opts, "throttling.bps-total-max", 0);
422         throttle_cfg->buckets[THROTTLE_BPS_READ].max  =
423             qemu_opt_get_number(opts, "throttling.bps-read-max", 0);
424         throttle_cfg->buckets[THROTTLE_BPS_WRITE].max =
425             qemu_opt_get_number(opts, "throttling.bps-write-max", 0);
426         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].max =
427             qemu_opt_get_number(opts, "throttling.iops-total-max", 0);
428         throttle_cfg->buckets[THROTTLE_OPS_READ].max =
429             qemu_opt_get_number(opts, "throttling.iops-read-max", 0);
430         throttle_cfg->buckets[THROTTLE_OPS_WRITE].max =
431             qemu_opt_get_number(opts, "throttling.iops-write-max", 0);
432 
433         throttle_cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
434             qemu_opt_get_number(opts, "throttling.bps-total-max-length", 1);
435         throttle_cfg->buckets[THROTTLE_BPS_READ].burst_length  =
436             qemu_opt_get_number(opts, "throttling.bps-read-max-length", 1);
437         throttle_cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
438             qemu_opt_get_number(opts, "throttling.bps-write-max-length", 1);
439         throttle_cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
440             qemu_opt_get_number(opts, "throttling.iops-total-max-length", 1);
441         throttle_cfg->buckets[THROTTLE_OPS_READ].burst_length =
442             qemu_opt_get_number(opts, "throttling.iops-read-max-length", 1);
443         throttle_cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
444             qemu_opt_get_number(opts, "throttling.iops-write-max-length", 1);
445 
446         throttle_cfg->op_size =
447             qemu_opt_get_number(opts, "throttling.iops-size", 0);
448 
449         if (!throttle_is_valid(throttle_cfg, errp)) {
450             return;
451         }
452     }
453 
454     if (detect_zeroes) {
455         *detect_zeroes =
456             qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
457                             qemu_opt_get(opts, "detect-zeroes"),
458                             BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
459                             &local_error);
460         if (local_error) {
461             error_propagate(errp, local_error);
462             return;
463         }
464     }
465 }
466 
account_get_opt(QemuOpts * opts,const char * name)467 static OnOffAuto account_get_opt(QemuOpts *opts, const char *name)
468 {
469     if (!qemu_opt_find(opts, name)) {
470         return ON_OFF_AUTO_AUTO;
471     }
472     if (qemu_opt_get_bool(opts, name, true)) {
473         return ON_OFF_AUTO_ON;
474     }
475     return ON_OFF_AUTO_OFF;
476 }
477 
478 /* Takes the ownership of bs_opts */
blockdev_init(const char * file,QDict * bs_opts,Error ** errp)479 static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
480                                    Error **errp)
481 {
482     const char *buf;
483     int bdrv_flags = 0;
484     int on_read_error, on_write_error;
485     OnOffAuto account_invalid, account_failed;
486     bool writethrough, read_only;
487     BlockBackend *blk;
488     BlockDriverState *bs;
489     ThrottleConfig cfg;
490     int snapshot = 0;
491     Error *error = NULL;
492     QemuOpts *opts;
493     QDict *interval_dict = NULL;
494     QList *interval_list = NULL;
495     const char *id;
496     BlockdevDetectZeroesOptions detect_zeroes =
497         BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
498     const char *throttling_group = NULL;
499 
500     /* Check common options by copying from bs_opts to opts, all other options
501      * stay in bs_opts for processing by bdrv_open(). */
502     id = qdict_get_try_str(bs_opts, "id");
503     opts = qemu_opts_create(&qemu_common_drive_opts, id, 1, errp);
504     if (!opts) {
505         goto err_no_opts;
506     }
507 
508     if (!qemu_opts_absorb_qdict(opts, bs_opts, errp)) {
509         goto early_err;
510     }
511 
512     if (id) {
513         qdict_del(bs_opts, "id");
514     }
515 
516     /* extract parameters */
517     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
518 
519     account_invalid = account_get_opt(opts, "stats-account-invalid");
520     account_failed = account_get_opt(opts, "stats-account-failed");
521 
522     writethrough = !qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, true);
523 
524     id = qemu_opts_id(opts);
525 
526     qdict_extract_subqdict(bs_opts, &interval_dict, "stats-intervals.");
527     qdict_array_split(interval_dict, &interval_list);
528 
529     if (qdict_size(interval_dict) != 0) {
530         error_setg(errp, "Invalid option stats-intervals.%s",
531                    qdict_first(interval_dict)->key);
532         goto early_err;
533     }
534 
535     extract_common_blockdev_options(opts, &bdrv_flags, &throttling_group, &cfg,
536                                     &detect_zeroes, &error);
537     if (error) {
538         error_propagate(errp, error);
539         goto early_err;
540     }
541 
542     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
543         if (is_help_option(buf)) {
544             qemu_printf("Supported formats:");
545             bdrv_iterate_format(bdrv_format_print, NULL, false);
546             qemu_printf("\nSupported formats (read-only):");
547             bdrv_iterate_format(bdrv_format_print, NULL, true);
548             qemu_printf("\n");
549             goto early_err;
550         }
551 
552         if (qdict_haskey(bs_opts, "driver")) {
553             error_setg(errp, "Cannot specify both 'driver' and 'format'");
554             goto early_err;
555         }
556         qdict_put_str(bs_opts, "driver", buf);
557     }
558 
559     on_write_error = BLOCKDEV_ON_ERROR_ENOSPC;
560     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
561         on_write_error = parse_block_error_action(buf, 0, &error);
562         if (error) {
563             error_propagate(errp, error);
564             goto early_err;
565         }
566     }
567 
568     on_read_error = BLOCKDEV_ON_ERROR_REPORT;
569     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
570         on_read_error = parse_block_error_action(buf, 1, &error);
571         if (error) {
572             error_propagate(errp, error);
573             goto early_err;
574         }
575     }
576 
577     if (snapshot) {
578         bdrv_flags |= BDRV_O_SNAPSHOT;
579     }
580 
581     read_only = qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false);
582 
583     /* init */
584     if ((!file || !*file) && !qdict_size(bs_opts)) {
585         BlockBackendRootState *blk_rs;
586 
587         blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
588         blk_rs = blk_get_root_state(blk);
589         blk_rs->open_flags    = bdrv_flags | (read_only ? 0 : BDRV_O_RDWR);
590         blk_rs->detect_zeroes = detect_zeroes;
591 
592         qobject_unref(bs_opts);
593     } else {
594         if (file && !*file) {
595             file = NULL;
596         }
597 
598         /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
599          * with other callers) rather than what we want as the real defaults.
600          * Apply the defaults here instead. */
601         qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
602         qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
603         qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY,
604                               read_only ? "on" : "off");
605         qdict_set_default_str(bs_opts, BDRV_OPT_AUTO_READ_ONLY, "on");
606         assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0);
607 
608         if (runstate_check(RUN_STATE_INMIGRATE)) {
609             bdrv_flags |= BDRV_O_INACTIVE;
610         }
611 
612         blk = blk_new_open(file, NULL, bs_opts, bdrv_flags, errp);
613         if (!blk) {
614             goto err_no_bs_opts;
615         }
616         bs = blk_bs(blk);
617 
618         bs->detect_zeroes = detect_zeroes;
619 
620         block_acct_setup(blk_get_stats(blk), account_invalid, account_failed);
621 
622         if (!parse_stats_intervals(blk_get_stats(blk), interval_list, errp)) {
623             blk_unref(blk);
624             blk = NULL;
625             goto err_no_bs_opts;
626         }
627     }
628 
629     /* disk I/O throttling */
630     if (throttle_enabled(&cfg)) {
631         if (!throttling_group) {
632             throttling_group = id;
633         }
634         blk_io_limits_enable(blk, throttling_group);
635         blk_set_io_limits(blk, &cfg);
636     }
637 
638     blk_set_enable_write_cache(blk, !writethrough);
639     blk_set_on_error(blk, on_read_error, on_write_error);
640 
641     if (!monitor_add_blk(blk, id, errp)) {
642         blk_unref(blk);
643         blk = NULL;
644         goto err_no_bs_opts;
645     }
646 
647 err_no_bs_opts:
648     qemu_opts_del(opts);
649     qobject_unref(interval_dict);
650     qobject_unref(interval_list);
651     return blk;
652 
653 early_err:
654     qemu_opts_del(opts);
655     qobject_unref(interval_dict);
656     qobject_unref(interval_list);
657 err_no_opts:
658     qobject_unref(bs_opts);
659     return NULL;
660 }
661 
662 /* Takes the ownership of bs_opts */
bds_tree_init(QDict * bs_opts,Error ** errp)663 BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)
664 {
665     int bdrv_flags = 0;
666 
667     GLOBAL_STATE_CODE();
668     /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
669      * with other callers) rather than what we want as the real defaults.
670      * Apply the defaults here instead. */
671     qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
672     qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
673     qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, "off");
674 
675     if (runstate_check(RUN_STATE_INMIGRATE)) {
676         bdrv_flags |= BDRV_O_INACTIVE;
677     }
678 
679     return bdrv_open(NULL, NULL, bs_opts, bdrv_flags, errp);
680 }
681 
blockdev_close_all_bdrv_states(void)682 void blockdev_close_all_bdrv_states(void)
683 {
684     BlockDriverState *bs, *next_bs;
685 
686     GLOBAL_STATE_CODE();
687     QTAILQ_FOREACH_SAFE(bs, &monitor_bdrv_states, monitor_list, next_bs) {
688         bdrv_unref(bs);
689     }
690 }
691 
692 /* Iterates over the list of monitor-owned BlockDriverStates */
bdrv_next_monitor_owned(BlockDriverState * bs)693 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs)
694 {
695     GLOBAL_STATE_CODE();
696     return bs ? QTAILQ_NEXT(bs, monitor_list)
697               : QTAILQ_FIRST(&monitor_bdrv_states);
698 }
699 
qemu_opt_rename(QemuOpts * opts,const char * from,const char * to,Error ** errp)700 static bool qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
701                             Error **errp)
702 {
703     const char *value;
704 
705     value = qemu_opt_get(opts, from);
706     if (value) {
707         if (qemu_opt_find(opts, to)) {
708             error_setg(errp, "'%s' and its alias '%s' can't be used at the "
709                        "same time", to, from);
710             return false;
711         }
712     }
713 
714     /* rename all items in opts */
715     while ((value = qemu_opt_get(opts, from))) {
716         qemu_opt_set(opts, to, value, &error_abort);
717         qemu_opt_unset(opts, from);
718     }
719     return true;
720 }
721 
722 QemuOptsList qemu_legacy_drive_opts = {
723     .name = "drive",
724     .head = QTAILQ_HEAD_INITIALIZER(qemu_legacy_drive_opts.head),
725     .desc = {
726         {
727             .name = "bus",
728             .type = QEMU_OPT_NUMBER,
729             .help = "bus number",
730         },{
731             .name = "unit",
732             .type = QEMU_OPT_NUMBER,
733             .help = "unit number (i.e. lun for scsi)",
734         },{
735             .name = "index",
736             .type = QEMU_OPT_NUMBER,
737             .help = "index number",
738         },{
739             .name = "media",
740             .type = QEMU_OPT_STRING,
741             .help = "media type (disk, cdrom)",
742         },{
743             .name = "if",
744             .type = QEMU_OPT_STRING,
745             .help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
746         },{
747             .name = "file",
748             .type = QEMU_OPT_STRING,
749             .help = "file name",
750         },
751 
752         /* Options that are passed on, but have special semantics with -drive */
753         {
754             .name = BDRV_OPT_READ_ONLY,
755             .type = QEMU_OPT_BOOL,
756             .help = "open drive file as read-only",
757         },{
758             .name = "rerror",
759             .type = QEMU_OPT_STRING,
760             .help = "read error action",
761         },{
762             .name = "werror",
763             .type = QEMU_OPT_STRING,
764             .help = "write error action",
765         },{
766             .name = "copy-on-read",
767             .type = QEMU_OPT_BOOL,
768             .help = "copy read data from backing file into image file",
769         },
770 
771         { /* end of list */ }
772     },
773 };
774 
drive_new(QemuOpts * all_opts,BlockInterfaceType block_default_type,Error ** errp)775 DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type,
776                      Error **errp)
777 {
778     const char *value;
779     BlockBackend *blk;
780     DriveInfo *dinfo = NULL;
781     QDict *bs_opts;
782     QemuOpts *legacy_opts;
783     DriveMediaType media = MEDIA_DISK;
784     BlockInterfaceType type;
785     int max_devs, bus_id, unit_id, index;
786     const char *werror, *rerror;
787     bool read_only = false;
788     bool copy_on_read;
789     const char *filename;
790     int i;
791 
792     GLOBAL_STATE_CODE();
793 
794     /* Change legacy command line options into QMP ones */
795     static const struct {
796         const char *from;
797         const char *to;
798     } opt_renames[] = {
799         { "iops",           "throttling.iops-total" },
800         { "iops_rd",        "throttling.iops-read" },
801         { "iops_wr",        "throttling.iops-write" },
802 
803         { "bps",            "throttling.bps-total" },
804         { "bps_rd",         "throttling.bps-read" },
805         { "bps_wr",         "throttling.bps-write" },
806 
807         { "iops_max",       "throttling.iops-total-max" },
808         { "iops_rd_max",    "throttling.iops-read-max" },
809         { "iops_wr_max",    "throttling.iops-write-max" },
810 
811         { "bps_max",        "throttling.bps-total-max" },
812         { "bps_rd_max",     "throttling.bps-read-max" },
813         { "bps_wr_max",     "throttling.bps-write-max" },
814 
815         { "iops_size",      "throttling.iops-size" },
816 
817         { "group",          "throttling.group" },
818 
819         { "readonly",       BDRV_OPT_READ_ONLY },
820     };
821 
822     for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
823         if (!qemu_opt_rename(all_opts, opt_renames[i].from,
824                              opt_renames[i].to, errp)) {
825             return NULL;
826         }
827     }
828 
829     value = qemu_opt_get(all_opts, "cache");
830     if (value) {
831         int flags = 0;
832         bool writethrough;
833 
834         if (bdrv_parse_cache_mode(value, &flags, &writethrough) != 0) {
835             error_setg(errp, "invalid cache option");
836             return NULL;
837         }
838 
839         /* Specific options take precedence */
840         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_WB)) {
841             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_WB,
842                               !writethrough, &error_abort);
843         }
844         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_DIRECT)) {
845             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_DIRECT,
846                               !!(flags & BDRV_O_NOCACHE), &error_abort);
847         }
848         if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_NO_FLUSH)) {
849             qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_NO_FLUSH,
850                               !!(flags & BDRV_O_NO_FLUSH), &error_abort);
851         }
852         qemu_opt_unset(all_opts, "cache");
853     }
854 
855     /* Get a QDict for processing the options */
856     bs_opts = qdict_new();
857     qemu_opts_to_qdict(all_opts, bs_opts);
858 
859     legacy_opts = qemu_opts_create(&qemu_legacy_drive_opts, NULL, 0,
860                                    &error_abort);
861     if (!qemu_opts_absorb_qdict(legacy_opts, bs_opts, errp)) {
862         goto fail;
863     }
864 
865     /* Media type */
866     value = qemu_opt_get(legacy_opts, "media");
867     if (value) {
868         if (!strcmp(value, "disk")) {
869             media = MEDIA_DISK;
870         } else if (!strcmp(value, "cdrom")) {
871             media = MEDIA_CDROM;
872             read_only = true;
873         } else {
874             error_setg(errp, "'%s' invalid media", value);
875             goto fail;
876         }
877     }
878 
879     /* copy-on-read is disabled with a warning for read-only devices */
880     read_only |= qemu_opt_get_bool(legacy_opts, BDRV_OPT_READ_ONLY, false);
881     copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false);
882 
883     if (read_only && copy_on_read) {
884         warn_report("disabling copy-on-read on read-only drive");
885         copy_on_read = false;
886     }
887 
888     qdict_put_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off");
889     qdict_put_str(bs_opts, "copy-on-read", copy_on_read ? "on" : "off");
890 
891     /* Controller type */
892     value = qemu_opt_get(legacy_opts, "if");
893     if (value) {
894         for (type = 0;
895              type < IF_COUNT && strcmp(value, if_name[type]);
896              type++) {
897         }
898         if (type == IF_COUNT) {
899             error_setg(errp, "unsupported bus type '%s'", value);
900             goto fail;
901         }
902     } else {
903         type = block_default_type;
904     }
905 
906     /* Device address specified by bus/unit or index.
907      * If none was specified, try to find the first free one. */
908     bus_id  = qemu_opt_get_number(legacy_opts, "bus", 0);
909     unit_id = qemu_opt_get_number(legacy_opts, "unit", -1);
910     index   = qemu_opt_get_number(legacy_opts, "index", -1);
911 
912     max_devs = if_max_devs[type];
913 
914     if (index != -1) {
915         if (bus_id != 0 || unit_id != -1) {
916             error_setg(errp, "index cannot be used with bus and unit");
917             goto fail;
918         }
919         bus_id = drive_index_to_bus_id(type, index);
920         unit_id = drive_index_to_unit_id(type, index);
921     }
922 
923     if (unit_id == -1) {
924        unit_id = 0;
925        while (drive_get(type, bus_id, unit_id) != NULL) {
926            unit_id++;
927            if (max_devs && unit_id >= max_devs) {
928                unit_id -= max_devs;
929                bus_id++;
930            }
931        }
932     }
933 
934     if (max_devs && unit_id >= max_devs) {
935         error_setg(errp, "unit %d too big (max is %d)", unit_id, max_devs - 1);
936         goto fail;
937     }
938 
939     if (drive_get(type, bus_id, unit_id) != NULL) {
940         error_setg(errp, "drive with bus=%d, unit=%d (index=%d) exists",
941                    bus_id, unit_id, index);
942         goto fail;
943     }
944 
945     /* no id supplied -> create one */
946     if (qemu_opts_id(all_opts) == NULL) {
947         char *new_id;
948         const char *mediastr = "";
949         if (type == IF_IDE || type == IF_SCSI) {
950             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
951         }
952         if (max_devs) {
953             new_id = g_strdup_printf("%s%i%s%i", if_name[type], bus_id,
954                                      mediastr, unit_id);
955         } else {
956             new_id = g_strdup_printf("%s%s%i", if_name[type],
957                                      mediastr, unit_id);
958         }
959         qdict_put_str(bs_opts, "id", new_id);
960         g_free(new_id);
961     }
962 
963     /* Add virtio block device */
964     if (type == IF_VIRTIO) {
965         QemuOpts *devopts;
966         devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
967                                    &error_abort);
968         qemu_opt_set(devopts, "driver", "virtio-blk", &error_abort);
969         qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
970                      &error_abort);
971     } else if (type == IF_XEN) {
972         QemuOpts *devopts;
973         devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
974                                    &error_abort);
975         qemu_opt_set(devopts, "driver",
976                      (media == MEDIA_CDROM) ? "xen-cdrom" : "xen-disk",
977                      &error_abort);
978         qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
979                      &error_abort);
980     }
981 
982     filename = qemu_opt_get(legacy_opts, "file");
983 
984     /* Check werror/rerror compatibility with if=... */
985     werror = qemu_opt_get(legacy_opts, "werror");
986     if (werror != NULL) {
987         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO &&
988             type != IF_NONE) {
989             error_setg(errp, "werror is not supported by this bus type");
990             goto fail;
991         }
992         qdict_put_str(bs_opts, "werror", werror);
993     }
994 
995     rerror = qemu_opt_get(legacy_opts, "rerror");
996     if (rerror != NULL) {
997         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI &&
998             type != IF_NONE) {
999             error_setg(errp, "rerror is not supported by this bus type");
1000             goto fail;
1001         }
1002         qdict_put_str(bs_opts, "rerror", rerror);
1003     }
1004 
1005     /* Actual block device init: Functionality shared with blockdev-add */
1006     blk = blockdev_init(filename, bs_opts, errp);
1007     bs_opts = NULL;
1008     if (!blk) {
1009         goto fail;
1010     }
1011 
1012     /* Create legacy DriveInfo */
1013     dinfo = g_malloc0(sizeof(*dinfo));
1014     dinfo->opts = all_opts;
1015 
1016     dinfo->type = type;
1017     dinfo->bus = bus_id;
1018     dinfo->unit = unit_id;
1019 
1020     blk_set_legacy_dinfo(blk, dinfo);
1021 
1022     switch(type) {
1023     case IF_IDE:
1024     case IF_SCSI:
1025     case IF_XEN:
1026     case IF_NONE:
1027         dinfo->media_cd = media == MEDIA_CDROM;
1028         break;
1029     default:
1030         break;
1031     }
1032 
1033 fail:
1034     qemu_opts_del(legacy_opts);
1035     qobject_unref(bs_opts);
1036     return dinfo;
1037 }
1038 
qmp_get_root_bs(const char * name,Error ** errp)1039 static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp)
1040 {
1041     BlockDriverState *bs;
1042 
1043     GRAPH_RDLOCK_GUARD_MAINLOOP();
1044 
1045     bs = bdrv_lookup_bs(name, name, errp);
1046     if (bs == NULL) {
1047         return NULL;
1048     }
1049 
1050     if (!bdrv_is_root_node(bs)) {
1051         error_setg(errp, "Need a root block node");
1052         return NULL;
1053     }
1054 
1055     if (!bdrv_is_inserted(bs)) {
1056         error_setg(errp, "Device has no medium");
1057         bs = NULL;
1058     }
1059 
1060     return bs;
1061 }
1062 
blockdev_do_action(TransactionAction * action,Error ** errp)1063 static void blockdev_do_action(TransactionAction *action, Error **errp)
1064 {
1065     TransactionActionList list;
1066 
1067     list.value = action;
1068     list.next = NULL;
1069     qmp_transaction(&list, NULL, errp);
1070 }
1071 
qmp_blockdev_snapshot_sync(const char * device,const char * node_name,const char * snapshot_file,const char * snapshot_node_name,const char * format,bool has_mode,NewImageMode mode,Error ** errp)1072 void qmp_blockdev_snapshot_sync(const char *device, const char *node_name,
1073                                 const char *snapshot_file,
1074                                 const char *snapshot_node_name,
1075                                 const char *format,
1076                                 bool has_mode, NewImageMode mode, Error **errp)
1077 {
1078     BlockdevSnapshotSync snapshot = {
1079         .device = (char *) device,
1080         .node_name = (char *) node_name,
1081         .snapshot_file = (char *) snapshot_file,
1082         .snapshot_node_name = (char *) snapshot_node_name,
1083         .format = (char *) format,
1084         .has_mode = has_mode,
1085         .mode = mode,
1086     };
1087     TransactionAction action = {
1088         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
1089         .u.blockdev_snapshot_sync.data = &snapshot,
1090     };
1091     blockdev_do_action(&action, errp);
1092 }
1093 
qmp_blockdev_snapshot(const char * node,const char * overlay,Error ** errp)1094 void qmp_blockdev_snapshot(const char *node, const char *overlay,
1095                            Error **errp)
1096 {
1097     BlockdevSnapshot snapshot_data = {
1098         .node = (char *) node,
1099         .overlay = (char *) overlay
1100     };
1101     TransactionAction action = {
1102         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT,
1103         .u.blockdev_snapshot.data = &snapshot_data,
1104     };
1105     blockdev_do_action(&action, errp);
1106 }
1107 
qmp_blockdev_snapshot_internal_sync(const char * device,const char * name,Error ** errp)1108 void qmp_blockdev_snapshot_internal_sync(const char *device,
1109                                          const char *name,
1110                                          Error **errp)
1111 {
1112     BlockdevSnapshotInternal snapshot = {
1113         .device = (char *) device,
1114         .name = (char *) name
1115     };
1116     TransactionAction action = {
1117         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
1118         .u.blockdev_snapshot_internal_sync.data = &snapshot,
1119     };
1120     blockdev_do_action(&action, errp);
1121 }
1122 
qmp_blockdev_snapshot_delete_internal_sync(const char * device,const char * id,const char * name,Error ** errp)1123 SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
1124                                                          const char *id,
1125                                                          const char *name,
1126                                                          Error **errp)
1127 {
1128     BlockDriverState *bs;
1129     QEMUSnapshotInfo sn;
1130     Error *local_err = NULL;
1131     SnapshotInfo *info = NULL;
1132     int ret;
1133 
1134     GLOBAL_STATE_CODE();
1135 
1136     bdrv_drain_all_begin();
1137     bdrv_graph_rdlock_main_loop();
1138 
1139     bs = qmp_get_root_bs(device, errp);
1140     if (!bs) {
1141         goto error;
1142     }
1143 
1144     if (!id && !name) {
1145         error_setg(errp, "Name or id must be provided");
1146         goto error;
1147     }
1148 
1149     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, errp)) {
1150         goto error;
1151     }
1152 
1153     ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
1154     if (local_err) {
1155         error_propagate(errp, local_err);
1156         goto error;
1157     }
1158     if (!ret) {
1159         error_setg(errp,
1160                    "Snapshot with id '%s' and name '%s' does not exist on "
1161                    "device '%s'",
1162                    STR_OR_NULL(id), STR_OR_NULL(name), device);
1163         goto error;
1164     }
1165 
1166     bdrv_snapshot_delete(bs, id, name, &local_err);
1167     if (local_err) {
1168         error_propagate(errp, local_err);
1169         goto error;
1170     }
1171 
1172     info = g_new0(SnapshotInfo, 1);
1173     info->id = g_strdup(sn.id_str);
1174     info->name = g_strdup(sn.name);
1175     info->date_nsec = sn.date_nsec;
1176     info->date_sec = sn.date_sec;
1177     info->vm_state_size = sn.vm_state_size;
1178     info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
1179     info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
1180     if (sn.icount != -1ULL) {
1181         info->icount = sn.icount;
1182         info->has_icount = true;
1183     }
1184 
1185 error:
1186     bdrv_graph_rdunlock_main_loop();
1187     bdrv_drain_all_end();
1188     return info;
1189 }
1190 
1191 /* internal snapshot private data */
1192 typedef struct InternalSnapshotState {
1193     BlockDriverState *bs;
1194     QEMUSnapshotInfo sn;
1195     bool created;
1196 } InternalSnapshotState;
1197 
1198 static void internal_snapshot_abort(void *opaque);
1199 static void internal_snapshot_clean(void *opaque);
1200 TransactionActionDrv internal_snapshot_drv = {
1201     .abort = internal_snapshot_abort,
1202     .clean = internal_snapshot_clean,
1203 };
1204 
internal_snapshot_action(BlockdevSnapshotInternal * internal,Transaction * tran,Error ** errp)1205 static void internal_snapshot_action(BlockdevSnapshotInternal *internal,
1206                                      Transaction *tran, Error **errp)
1207 {
1208     Error *local_err = NULL;
1209     const char *device;
1210     const char *name;
1211     BlockDriverState *bs, *check_bs;
1212     QEMUSnapshotInfo old_sn, *sn;
1213     bool ret;
1214     int64_t rt;
1215     InternalSnapshotState *state = g_new0(InternalSnapshotState, 1);
1216     int ret1;
1217 
1218     GLOBAL_STATE_CODE();
1219     bdrv_graph_rdlock_main_loop();
1220 
1221     tran_add(tran, &internal_snapshot_drv, state);
1222 
1223     device = internal->device;
1224     name = internal->name;
1225 
1226     bs = qmp_get_root_bs(device, errp);
1227     if (!bs) {
1228         bdrv_graph_rdunlock_main_loop();
1229         return;
1230     }
1231 
1232     state->bs = bs;
1233 
1234     /* Need to drain while unlocked. */
1235     bdrv_graph_rdunlock_main_loop();
1236     /* Paired with .clean() */
1237     bdrv_drained_begin(bs);
1238 
1239     GRAPH_RDLOCK_GUARD_MAINLOOP();
1240 
1241     /* Make sure the root bs did not change with the drain. */
1242     check_bs = qmp_get_root_bs(device, errp);
1243     if (bs != check_bs) {
1244         if (check_bs) {
1245             error_setg(errp, "Block node of device '%s' unexpectedly changed",
1246                        device);
1247         } /* else errp is already set */
1248         return;
1249     }
1250 
1251     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {
1252         return;
1253     }
1254 
1255     if (bdrv_is_read_only(bs)) {
1256         error_setg(errp, "Device '%s' is read only", device);
1257         return;
1258     }
1259 
1260     if (!bdrv_can_snapshot(bs)) {
1261         error_setg(errp, "Block format '%s' used by device '%s' "
1262                    "does not support internal snapshots",
1263                    bs->drv->format_name, device);
1264         return;
1265     }
1266 
1267     if (!strlen(name)) {
1268         error_setg(errp, "Name is empty");
1269         return;
1270     }
1271 
1272     /* check whether a snapshot with name exist */
1273     ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn,
1274                                             &local_err);
1275     if (local_err) {
1276         error_propagate(errp, local_err);
1277         return;
1278     } else if (ret) {
1279         error_setg(errp,
1280                    "Snapshot with name '%s' already exists on device '%s'",
1281                    name, device);
1282         return;
1283     }
1284 
1285     /* 3. take the snapshot */
1286     sn = &state->sn;
1287     pstrcpy(sn->name, sizeof(sn->name), name);
1288     rt = g_get_real_time();
1289     sn->date_sec = rt / G_USEC_PER_SEC;
1290     sn->date_nsec = (rt % G_USEC_PER_SEC) * 1000;
1291     sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
1292     if (replay_mode != REPLAY_MODE_NONE) {
1293         sn->icount = replay_get_current_icount();
1294     } else {
1295         sn->icount = -1ULL;
1296     }
1297 
1298     ret1 = bdrv_snapshot_create(bs, sn);
1299     if (ret1 < 0) {
1300         error_setg_errno(errp, -ret1,
1301                          "Failed to create snapshot '%s' on device '%s'",
1302                          name, device);
1303         return;
1304     }
1305 
1306     /* 4. succeed, mark a snapshot is created */
1307     state->created = true;
1308 }
1309 
internal_snapshot_abort(void * opaque)1310 static void internal_snapshot_abort(void *opaque)
1311 {
1312     InternalSnapshotState *state = opaque;
1313     BlockDriverState *bs = state->bs;
1314     QEMUSnapshotInfo *sn = &state->sn;
1315     Error *local_error = NULL;
1316 
1317     GLOBAL_STATE_CODE();
1318 
1319     if (!state->created) {
1320         return;
1321     }
1322 
1323     bdrv_drain_all_begin();
1324     bdrv_graph_rdlock_main_loop();
1325 
1326     if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {
1327         error_reportf_err(local_error,
1328                           "Failed to delete snapshot with id '%s' and "
1329                           "name '%s' on device '%s' in abort: ",
1330                           sn->id_str, sn->name,
1331                           bdrv_get_device_name(bs));
1332     }
1333     bdrv_graph_rdunlock_main_loop();
1334     bdrv_drain_all_end();
1335 }
1336 
internal_snapshot_clean(void * opaque)1337 static void internal_snapshot_clean(void *opaque)
1338 {
1339     g_autofree InternalSnapshotState *state = opaque;
1340 
1341     if (!state->bs) {
1342         return;
1343     }
1344 
1345     bdrv_drained_end(state->bs);
1346 }
1347 
1348 /* external snapshot private data */
1349 typedef struct ExternalSnapshotState {
1350     BlockDriverState *old_bs;
1351     BlockDriverState *new_bs;
1352     bool overlay_appended;
1353 } ExternalSnapshotState;
1354 
1355 static void external_snapshot_commit(void *opaque);
1356 static void external_snapshot_abort(void *opaque);
1357 static void external_snapshot_clean(void *opaque);
1358 TransactionActionDrv external_snapshot_drv = {
1359     .commit = external_snapshot_commit,
1360     .abort = external_snapshot_abort,
1361     .clean = external_snapshot_clean,
1362 };
1363 
external_snapshot_action(TransactionAction * action,Transaction * tran,Error ** errp)1364 static void external_snapshot_action(TransactionAction *action,
1365                                      Transaction *tran, Error **errp)
1366 {
1367     int ret;
1368     int flags = 0;
1369     QDict *options = NULL;
1370     Error *local_err = NULL;
1371     /* Device and node name of the image to generate the snapshot from */
1372     const char *device;
1373     const char *node_name;
1374     /* Reference to the new image (for 'blockdev-snapshot') */
1375     const char *snapshot_ref;
1376     /* File name of the new image (for 'blockdev-snapshot-sync') */
1377     const char *new_image_file;
1378     ExternalSnapshotState *state = g_new0(ExternalSnapshotState, 1);
1379     uint64_t perm, shared;
1380     BlockDriverState *check_bs;
1381 
1382     /* TODO We'll eventually have to take a writer lock in this function */
1383     bdrv_graph_rdlock_main_loop();
1384 
1385     tran_add(tran, &external_snapshot_drv, state);
1386 
1387     /* 'blockdev-snapshot' and 'blockdev-snapshot-sync' have similar
1388      * purpose but a different set of parameters */
1389     switch (action->type) {
1390     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
1391         {
1392             BlockdevSnapshot *s = action->u.blockdev_snapshot.data;
1393             device = s->node;
1394             node_name = s->node;
1395             new_image_file = NULL;
1396             snapshot_ref = s->overlay;
1397         }
1398         break;
1399     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
1400         {
1401             BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1402             device = s->device;
1403             node_name = s->node_name;
1404             new_image_file = s->snapshot_file;
1405             snapshot_ref = NULL;
1406         }
1407         break;
1408     default:
1409         g_assert_not_reached();
1410     }
1411 
1412     /* start processing */
1413 
1414     state->old_bs = bdrv_lookup_bs(device, node_name, errp);
1415     if (!state->old_bs) {
1416         bdrv_graph_rdunlock_main_loop();
1417         return;
1418     }
1419 
1420     /* Need to drain while unlocked. */
1421     bdrv_graph_rdunlock_main_loop();
1422     /* Paired with .clean() */
1423     bdrv_drained_begin(state->old_bs);
1424     GRAPH_RDLOCK_GUARD_MAINLOOP();
1425 
1426     /* Make sure the associated bs did not change with the drain. */
1427     check_bs = bdrv_lookup_bs(device, node_name, errp);
1428     if (state->old_bs != check_bs) {
1429         if (check_bs) {
1430             error_setg(errp, "Block node of device '%s' unexpectedly changed",
1431                        device);
1432         } /* else errp is already set */
1433         return;
1434     }
1435 
1436     if (!bdrv_is_inserted(state->old_bs)) {
1437         error_setg(errp, "Device '%s' has no medium",
1438                    bdrv_get_device_or_node_name(state->old_bs));
1439         return;
1440     }
1441 
1442     if (bdrv_op_is_blocked(state->old_bs,
1443                            BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
1444         return;
1445     }
1446 
1447     if (!bdrv_is_read_only(state->old_bs)) {
1448         ret = bdrv_flush(state->old_bs);
1449         if (ret < 0) {
1450             error_setg_errno(errp, -ret, "Write to node '%s' failed",
1451                              bdrv_get_device_or_node_name(state->old_bs));
1452             return;
1453         }
1454     }
1455 
1456     if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
1457         BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
1458         const char *format = s->format ?: "qcow2";
1459         enum NewImageMode mode;
1460         const char *snapshot_node_name = s->snapshot_node_name;
1461 
1462         if (node_name && !snapshot_node_name) {
1463             error_setg(errp, "New overlay node-name missing");
1464             return;
1465         }
1466 
1467         if (snapshot_node_name &&
1468             bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
1469             error_setg(errp, "New overlay node-name already in use");
1470             return;
1471         }
1472 
1473         flags = state->old_bs->open_flags;
1474         flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ);
1475         flags |= BDRV_O_NO_BACKING;
1476 
1477         /* create new image w/backing file */
1478         mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1479         if (mode != NEW_IMAGE_MODE_EXISTING) {
1480             int64_t size = bdrv_getlength(state->old_bs);
1481             if (size < 0) {
1482                 error_setg_errno(errp, -size, "bdrv_getlength failed");
1483                 return;
1484             }
1485             bdrv_refresh_filename(state->old_bs);
1486 
1487             bdrv_img_create(new_image_file, format,
1488                             state->old_bs->filename,
1489                             state->old_bs->drv->format_name,
1490                             NULL, size, flags, false, &local_err);
1491 
1492             if (local_err) {
1493                 error_propagate(errp, local_err);
1494                 return;
1495             }
1496         }
1497 
1498         options = qdict_new();
1499         if (snapshot_node_name) {
1500             qdict_put_str(options, "node-name", snapshot_node_name);
1501         }
1502         qdict_put_str(options, "driver", format);
1503     }
1504 
1505     state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
1506                               errp);
1507 
1508     /* We will manually add the backing_hd field to the bs later */
1509     if (!state->new_bs) {
1510         return;
1511     }
1512 
1513     /*
1514      * Allow attaching a backing file to an overlay that's already in use only
1515      * if the parents don't assume that they are already seeing a valid image.
1516      * (Specifically, allow it as a mirror target, which is write-only access.)
1517      */
1518     bdrv_get_cumulative_perm(state->new_bs, &perm, &shared);
1519     if (perm & BLK_PERM_CONSISTENT_READ) {
1520         error_setg(errp, "The overlay is already in use");
1521         return;
1522     }
1523 
1524     if (state->new_bs->drv->is_filter) {
1525         error_setg(errp, "Filters cannot be used as overlays");
1526         return;
1527     }
1528 
1529     if (bdrv_cow_child(state->new_bs)) {
1530         error_setg(errp, "The overlay already has a backing image");
1531         return;
1532     }
1533 
1534     if (!state->new_bs->drv->supports_backing) {
1535         error_setg(errp, "The overlay does not support backing images");
1536         return;
1537     }
1538 
1539     /*
1540      * Older QEMU versions have allowed adding an active parent node to an
1541      * inactive child node. This is unsafe in the general case, but there is an
1542      * important use case, which is taking a VM snapshot with migration to file
1543      * and then adding an external snapshot while the VM is still stopped and
1544      * images are inactive. Requiring the user to explicitly create the overlay
1545      * as inactive would break compatibility, so just do it automatically here
1546      * to keep this working.
1547      */
1548     if (bdrv_is_inactive(state->old_bs) && !bdrv_is_inactive(state->new_bs)) {
1549         ret = bdrv_inactivate(state->new_bs, errp);
1550         if (ret < 0) {
1551             return;
1552         }
1553     }
1554 
1555     ret = bdrv_append(state->new_bs, state->old_bs, errp);
1556     if (ret < 0) {
1557         return;
1558     }
1559     state->overlay_appended = true;
1560 }
1561 
external_snapshot_commit(void * opaque)1562 static void external_snapshot_commit(void *opaque)
1563 {
1564     ExternalSnapshotState *state = opaque;
1565 
1566     /* We don't need (or want) to use the transactional
1567      * bdrv_reopen_multiple() across all the entries at once, because we
1568      * don't want to abort all of them if one of them fails the reopen */
1569     if (!qatomic_read(&state->old_bs->copy_on_read)) {
1570         bdrv_reopen_set_read_only(state->old_bs, true, NULL);
1571     }
1572 }
1573 
external_snapshot_abort(void * opaque)1574 static void external_snapshot_abort(void *opaque)
1575 {
1576     ExternalSnapshotState *state = opaque;
1577     if (state->new_bs) {
1578         if (state->overlay_appended) {
1579             AioContext *aio_context;
1580             AioContext *tmp_context;
1581             int ret;
1582 
1583             aio_context = bdrv_get_aio_context(state->old_bs);
1584 
1585             bdrv_ref(state->old_bs);   /* we can't let bdrv_set_backind_hd()
1586                                           close state->old_bs; we need it */
1587             bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
1588 
1589             /*
1590              * The call to bdrv_set_backing_hd() above returns state->old_bs to
1591              * the main AioContext. As we're still going to be using it, return
1592              * it to the AioContext it was before.
1593              */
1594             tmp_context = bdrv_get_aio_context(state->old_bs);
1595             if (aio_context != tmp_context) {
1596                 ret = bdrv_try_change_aio_context(state->old_bs,
1597                                                   aio_context, NULL, NULL);
1598                 assert(ret == 0);
1599             }
1600 
1601             bdrv_drained_begin(state->new_bs);
1602             bdrv_graph_wrlock();
1603             bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
1604             bdrv_graph_wrunlock();
1605             bdrv_drained_end(state->new_bs);
1606 
1607             bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
1608         }
1609     }
1610 }
1611 
external_snapshot_clean(void * opaque)1612 static void external_snapshot_clean(void *opaque)
1613 {
1614     g_autofree ExternalSnapshotState *state = opaque;
1615 
1616     if (!state->old_bs) {
1617         return;
1618     }
1619 
1620     bdrv_drained_end(state->old_bs);
1621     bdrv_unref(state->new_bs);
1622 }
1623 
1624 typedef struct DriveBackupState {
1625     BlockDriverState *bs;
1626     BlockJob *job;
1627 } DriveBackupState;
1628 
1629 static BlockJob *do_backup_common(BackupCommon *backup,
1630                                   BlockDriverState *bs,
1631                                   BlockDriverState *target_bs,
1632                                   AioContext *aio_context,
1633                                   JobTxn *txn, Error **errp);
1634 
1635 static void drive_backup_commit(void *opaque);
1636 static void drive_backup_abort(void *opaque);
1637 static void drive_backup_clean(void *opaque);
1638 TransactionActionDrv drive_backup_drv = {
1639     .commit = drive_backup_commit,
1640     .abort = drive_backup_abort,
1641     .clean = drive_backup_clean,
1642 };
1643 
drive_backup_action(DriveBackup * backup,JobTxn * block_job_txn,Transaction * tran,Error ** errp)1644 static void drive_backup_action(DriveBackup *backup,
1645                                 JobTxn *block_job_txn,
1646                                 Transaction *tran, Error **errp)
1647 {
1648     DriveBackupState *state = g_new0(DriveBackupState, 1);
1649     BlockDriverState *bs;
1650     BlockDriverState *target_bs;
1651     BlockDriverState *source = NULL;
1652     AioContext *aio_context;
1653     const char *format;
1654     QDict *options;
1655     Error *local_err = NULL;
1656     int flags;
1657     int64_t size;
1658     bool set_backing_hd = false;
1659     int ret;
1660 
1661     GLOBAL_STATE_CODE();
1662 
1663     tran_add(tran, &drive_backup_drv, state);
1664 
1665     if (!backup->has_mode) {
1666         backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1667     }
1668 
1669     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1670     if (!bs) {
1671         return;
1672     }
1673 
1674     if (!bs->drv) {
1675         error_setg(errp, "Device has no medium");
1676         return;
1677     }
1678 
1679     aio_context = bdrv_get_aio_context(bs);
1680 
1681     state->bs = bs;
1682     /* Paired with .clean() */
1683     bdrv_drained_begin(bs);
1684 
1685     format = backup->format;
1686     if (!format && backup->mode != NEW_IMAGE_MODE_EXISTING) {
1687         format = bs->drv->format_name;
1688     }
1689 
1690     /* Early check to avoid creating target */
1691     bdrv_graph_rdlock_main_loop();
1692     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
1693         bdrv_graph_rdunlock_main_loop();
1694         return;
1695     }
1696 
1697     flags = bs->open_flags | BDRV_O_RDWR;
1698 
1699     /*
1700      * See if we have a backing HD we can use to create our new image
1701      * on top of.
1702      */
1703     if (backup->sync == MIRROR_SYNC_MODE_TOP) {
1704         /*
1705          * Backup will not replace the source by the target, so none
1706          * of the filters skipped here will be removed (in contrast to
1707          * mirror).  Therefore, we can skip all of them when looking
1708          * for the first COW relationship.
1709          */
1710         source = bdrv_cow_bs(bdrv_skip_filters(bs));
1711         if (!source) {
1712             backup->sync = MIRROR_SYNC_MODE_FULL;
1713         }
1714     }
1715     if (backup->sync == MIRROR_SYNC_MODE_NONE) {
1716         source = bs;
1717         flags |= BDRV_O_NO_BACKING;
1718         set_backing_hd = true;
1719     }
1720     bdrv_graph_rdunlock_main_loop();
1721 
1722     size = bdrv_getlength(bs);
1723     if (size < 0) {
1724         error_setg_errno(errp, -size, "bdrv_getlength failed");
1725         return;
1726     }
1727 
1728     if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
1729         assert(format);
1730         if (source) {
1731             /* Implicit filters should not appear in the filename */
1732             BlockDriverState *explicit_backing;
1733 
1734             bdrv_graph_rdlock_main_loop();
1735             explicit_backing = bdrv_skip_implicit_filters(source);
1736             bdrv_refresh_filename(explicit_backing);
1737             bdrv_graph_rdunlock_main_loop();
1738 
1739             bdrv_img_create(backup->target, format,
1740                             explicit_backing->filename,
1741                             explicit_backing->drv->format_name, NULL,
1742                             size, flags, false, &local_err);
1743         } else {
1744             bdrv_img_create(backup->target, format, NULL, NULL, NULL,
1745                             size, flags, false, &local_err);
1746         }
1747     }
1748 
1749     if (local_err) {
1750         error_propagate(errp, local_err);
1751         return;
1752     }
1753 
1754     options = qdict_new();
1755     qdict_put_str(options, "discard", "unmap");
1756     qdict_put_str(options, "detect-zeroes", "unmap");
1757     if (format) {
1758         qdict_put_str(options, "driver", format);
1759     }
1760 
1761     target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
1762     if (!target_bs) {
1763         return;
1764     }
1765 
1766     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1767     if (ret < 0) {
1768         bdrv_unref(target_bs);
1769         return;
1770     }
1771 
1772     if (set_backing_hd) {
1773         if (bdrv_set_backing_hd(target_bs, source, errp) < 0) {
1774             goto unref;
1775         }
1776     }
1777 
1778     state->job = do_backup_common(qapi_DriveBackup_base(backup),
1779                                   bs, target_bs, aio_context,
1780                                   block_job_txn, errp);
1781 
1782 unref:
1783     bdrv_unref(target_bs);
1784 }
1785 
drive_backup_commit(void * opaque)1786 static void drive_backup_commit(void *opaque)
1787 {
1788     DriveBackupState *state = opaque;
1789 
1790     assert(state->job);
1791     job_start(&state->job->job);
1792 }
1793 
drive_backup_abort(void * opaque)1794 static void drive_backup_abort(void *opaque)
1795 {
1796     DriveBackupState *state = opaque;
1797 
1798     if (state->job) {
1799         job_cancel_sync(&state->job->job, true);
1800     }
1801 }
1802 
drive_backup_clean(void * opaque)1803 static void drive_backup_clean(void *opaque)
1804 {
1805     g_autofree DriveBackupState *state = opaque;
1806 
1807     if (!state->bs) {
1808         return;
1809     }
1810 
1811     bdrv_drained_end(state->bs);
1812 }
1813 
1814 typedef struct BlockdevBackupState {
1815     BlockDriverState *bs;
1816     BlockJob *job;
1817 } BlockdevBackupState;
1818 
1819 static void blockdev_backup_commit(void *opaque);
1820 static void blockdev_backup_abort(void *opaque);
1821 static void blockdev_backup_clean(void *opaque);
1822 TransactionActionDrv blockdev_backup_drv = {
1823     .commit = blockdev_backup_commit,
1824     .abort = blockdev_backup_abort,
1825     .clean = blockdev_backup_clean,
1826 };
1827 
blockdev_backup_action(BlockdevBackup * backup,JobTxn * block_job_txn,Transaction * tran,Error ** errp)1828 static void blockdev_backup_action(BlockdevBackup *backup,
1829                                    JobTxn *block_job_txn,
1830                                    Transaction *tran, Error **errp)
1831 {
1832     BlockdevBackupState *state = g_new0(BlockdevBackupState, 1);
1833     BlockDriverState *bs;
1834     BlockDriverState *target_bs;
1835     AioContext *aio_context;
1836     int ret;
1837 
1838     tran_add(tran, &blockdev_backup_drv, state);
1839 
1840     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1841     if (!bs) {
1842         return;
1843     }
1844 
1845     target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
1846     if (!target_bs) {
1847         return;
1848     }
1849 
1850     /* Honor bdrv_try_change_aio_context() context acquisition requirements. */
1851     aio_context = bdrv_get_aio_context(bs);
1852 
1853     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1854     if (ret < 0) {
1855         return;
1856     }
1857 
1858     state->bs = bs;
1859 
1860     /* Paired with .clean() */
1861     bdrv_drained_begin(state->bs);
1862 
1863     state->job = do_backup_common(qapi_BlockdevBackup_base(backup),
1864                                   bs, target_bs, aio_context,
1865                                   block_job_txn, errp);
1866 }
1867 
blockdev_backup_commit(void * opaque)1868 static void blockdev_backup_commit(void *opaque)
1869 {
1870     BlockdevBackupState *state = opaque;
1871 
1872     assert(state->job);
1873     job_start(&state->job->job);
1874 }
1875 
blockdev_backup_abort(void * opaque)1876 static void blockdev_backup_abort(void *opaque)
1877 {
1878     BlockdevBackupState *state = opaque;
1879 
1880     if (state->job) {
1881         job_cancel_sync(&state->job->job, true);
1882     }
1883 }
1884 
blockdev_backup_clean(void * opaque)1885 static void blockdev_backup_clean(void *opaque)
1886 {
1887     g_autofree BlockdevBackupState *state = opaque;
1888 
1889     if (!state->bs) {
1890         return;
1891     }
1892 
1893     bdrv_drained_end(state->bs);
1894 }
1895 
1896 typedef struct BlockDirtyBitmapState {
1897     BdrvDirtyBitmap *bitmap;
1898     BlockDriverState *bs;
1899     HBitmap *backup;
1900     bool was_enabled;
1901 } BlockDirtyBitmapState;
1902 
1903 static void block_dirty_bitmap_add_abort(void *opaque);
1904 TransactionActionDrv block_dirty_bitmap_add_drv = {
1905     .abort = block_dirty_bitmap_add_abort,
1906     .clean = g_free,
1907 };
1908 
block_dirty_bitmap_add_action(BlockDirtyBitmapAdd * action,Transaction * tran,Error ** errp)1909 static void block_dirty_bitmap_add_action(BlockDirtyBitmapAdd *action,
1910                                           Transaction *tran, Error **errp)
1911 {
1912     Error *local_err = NULL;
1913     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1914 
1915     tran_add(tran, &block_dirty_bitmap_add_drv, state);
1916 
1917     /* AIO context taken and released within qmp_block_dirty_bitmap_add */
1918     qmp_block_dirty_bitmap_add(action->node, action->name,
1919                                action->has_granularity, action->granularity,
1920                                action->has_persistent, action->persistent,
1921                                action->has_disabled, action->disabled,
1922                                &local_err);
1923 
1924     if (!local_err) {
1925         state->bitmap = block_dirty_bitmap_lookup(action->node, action->name,
1926                                                   NULL, &error_abort);
1927     } else {
1928         error_propagate(errp, local_err);
1929     }
1930 }
1931 
block_dirty_bitmap_add_abort(void * opaque)1932 static void block_dirty_bitmap_add_abort(void *opaque)
1933 {
1934     BlockDirtyBitmapState *state = opaque;
1935 
1936     if (state->bitmap) {
1937         bdrv_release_dirty_bitmap(state->bitmap);
1938     }
1939 }
1940 
1941 static void block_dirty_bitmap_restore(void *opaque);
1942 static void block_dirty_bitmap_free_backup(void *opaque);
1943 TransactionActionDrv block_dirty_bitmap_clear_drv = {
1944     .abort = block_dirty_bitmap_restore,
1945     .commit = block_dirty_bitmap_free_backup,
1946     .clean = g_free,
1947 };
1948 
block_dirty_bitmap_clear_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)1949 static void block_dirty_bitmap_clear_action(BlockDirtyBitmap *action,
1950                                             Transaction *tran, Error **errp)
1951 {
1952     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1953 
1954     tran_add(tran, &block_dirty_bitmap_clear_drv, state);
1955 
1956     state->bitmap = block_dirty_bitmap_lookup(action->node,
1957                                               action->name,
1958                                               &state->bs,
1959                                               errp);
1960     if (!state->bitmap) {
1961         return;
1962     }
1963 
1964     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_DEFAULT, errp)) {
1965         return;
1966     }
1967 
1968     bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
1969 }
1970 
block_dirty_bitmap_restore(void * opaque)1971 static void block_dirty_bitmap_restore(void *opaque)
1972 {
1973     BlockDirtyBitmapState *state = opaque;
1974 
1975     if (state->backup) {
1976         bdrv_restore_dirty_bitmap(state->bitmap, state->backup);
1977     }
1978 }
1979 
block_dirty_bitmap_free_backup(void * opaque)1980 static void block_dirty_bitmap_free_backup(void *opaque)
1981 {
1982     BlockDirtyBitmapState *state = opaque;
1983 
1984     hbitmap_free(state->backup);
1985 }
1986 
1987 static void block_dirty_bitmap_enable_abort(void *opaque);
1988 TransactionActionDrv block_dirty_bitmap_enable_drv = {
1989     .abort = block_dirty_bitmap_enable_abort,
1990     .clean = g_free,
1991 };
1992 
block_dirty_bitmap_enable_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)1993 static void block_dirty_bitmap_enable_action(BlockDirtyBitmap *action,
1994                                              Transaction *tran, Error **errp)
1995 {
1996     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1997 
1998     tran_add(tran, &block_dirty_bitmap_enable_drv, state);
1999 
2000     state->bitmap = block_dirty_bitmap_lookup(action->node,
2001                                               action->name,
2002                                               NULL,
2003                                               errp);
2004     if (!state->bitmap) {
2005         return;
2006     }
2007 
2008     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2009         return;
2010     }
2011 
2012     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2013     bdrv_enable_dirty_bitmap(state->bitmap);
2014 }
2015 
block_dirty_bitmap_enable_abort(void * opaque)2016 static void block_dirty_bitmap_enable_abort(void *opaque)
2017 {
2018     BlockDirtyBitmapState *state = opaque;
2019 
2020     if (!state->was_enabled) {
2021         bdrv_disable_dirty_bitmap(state->bitmap);
2022     }
2023 }
2024 
2025 static void block_dirty_bitmap_disable_abort(void *opaque);
2026 TransactionActionDrv block_dirty_bitmap_disable_drv = {
2027     .abort = block_dirty_bitmap_disable_abort,
2028     .clean = g_free,
2029 };
2030 
block_dirty_bitmap_disable_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)2031 static void block_dirty_bitmap_disable_action(BlockDirtyBitmap *action,
2032                                               Transaction *tran, Error **errp)
2033 {
2034     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2035 
2036     tran_add(tran, &block_dirty_bitmap_disable_drv, state);
2037 
2038     state->bitmap = block_dirty_bitmap_lookup(action->node,
2039                                               action->name,
2040                                               NULL,
2041                                               errp);
2042     if (!state->bitmap) {
2043         return;
2044     }
2045 
2046     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2047         return;
2048     }
2049 
2050     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2051     bdrv_disable_dirty_bitmap(state->bitmap);
2052 }
2053 
block_dirty_bitmap_disable_abort(void * opaque)2054 static void block_dirty_bitmap_disable_abort(void *opaque)
2055 {
2056     BlockDirtyBitmapState *state = opaque;
2057 
2058     if (state->was_enabled) {
2059         bdrv_enable_dirty_bitmap(state->bitmap);
2060     }
2061 }
2062 
2063 TransactionActionDrv block_dirty_bitmap_merge_drv = {
2064     .commit = block_dirty_bitmap_free_backup,
2065     .abort = block_dirty_bitmap_restore,
2066     .clean = g_free,
2067 };
2068 
block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge * action,Transaction * tran,Error ** errp)2069 static void block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge *action,
2070                                             Transaction *tran, Error **errp)
2071 {
2072     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2073 
2074     tran_add(tran, &block_dirty_bitmap_merge_drv, state);
2075 
2076     state->bitmap = block_dirty_bitmap_merge(action->node, action->target,
2077                                              action->bitmaps, &state->backup,
2078                                              errp);
2079 }
2080 
2081 static void block_dirty_bitmap_remove_commit(void *opaque);
2082 static void block_dirty_bitmap_remove_abort(void *opaque);
2083 TransactionActionDrv block_dirty_bitmap_remove_drv = {
2084     .commit = block_dirty_bitmap_remove_commit,
2085     .abort = block_dirty_bitmap_remove_abort,
2086     .clean = g_free,
2087 };
2088 
block_dirty_bitmap_remove_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)2089 static void block_dirty_bitmap_remove_action(BlockDirtyBitmap *action,
2090                                              Transaction *tran, Error **errp)
2091 {
2092     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2093 
2094     tran_add(tran, &block_dirty_bitmap_remove_drv, state);
2095 
2096 
2097     state->bitmap = block_dirty_bitmap_remove(action->node, action->name,
2098                                               false, &state->bs, errp);
2099     if (state->bitmap) {
2100         bdrv_dirty_bitmap_skip_store(state->bitmap, true);
2101         bdrv_dirty_bitmap_set_busy(state->bitmap, true);
2102     }
2103 }
2104 
block_dirty_bitmap_remove_abort(void * opaque)2105 static void block_dirty_bitmap_remove_abort(void *opaque)
2106 {
2107     BlockDirtyBitmapState *state = opaque;
2108 
2109     if (state->bitmap) {
2110         bdrv_dirty_bitmap_skip_store(state->bitmap, false);
2111         bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2112     }
2113 }
2114 
block_dirty_bitmap_remove_commit(void * opaque)2115 static void block_dirty_bitmap_remove_commit(void *opaque)
2116 {
2117     BlockDirtyBitmapState *state = opaque;
2118 
2119     bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2120     bdrv_release_dirty_bitmap(state->bitmap);
2121 }
2122 
2123 static void abort_commit(void *opaque);
2124 TransactionActionDrv abort_drv = {
2125     .commit = abort_commit,
2126 };
2127 
abort_action(Transaction * tran,Error ** errp)2128 static void abort_action(Transaction *tran, Error **errp)
2129 {
2130     tran_add(tran, &abort_drv, NULL);
2131     error_setg(errp, "Transaction aborted using Abort action");
2132 }
2133 
abort_commit(void * opaque)2134 static void abort_commit(void *opaque)
2135 {
2136     g_assert_not_reached(); /* this action never succeeds */
2137 }
2138 
transaction_action(TransactionAction * act,JobTxn * block_job_txn,Transaction * tran,Error ** errp)2139 static void transaction_action(TransactionAction *act, JobTxn *block_job_txn,
2140                                Transaction *tran, Error **errp)
2141 {
2142     switch (act->type) {
2143     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
2144     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
2145         external_snapshot_action(act, tran, errp);
2146         return;
2147     case TRANSACTION_ACTION_KIND_DRIVE_BACKUP:
2148         drive_backup_action(act->u.drive_backup.data,
2149                             block_job_txn, tran, errp);
2150         return;
2151     case TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP:
2152         blockdev_backup_action(act->u.blockdev_backup.data,
2153                                block_job_txn, tran, errp);
2154         return;
2155     case TRANSACTION_ACTION_KIND_ABORT:
2156         abort_action(tran, errp);
2157         return;
2158     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC:
2159         internal_snapshot_action(act->u.blockdev_snapshot_internal_sync.data,
2160                                  tran, errp);
2161         return;
2162     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD:
2163         block_dirty_bitmap_add_action(act->u.block_dirty_bitmap_add.data,
2164                                       tran, errp);
2165         return;
2166     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR:
2167         block_dirty_bitmap_clear_action(act->u.block_dirty_bitmap_clear.data,
2168                                         tran, errp);
2169         return;
2170     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ENABLE:
2171         block_dirty_bitmap_enable_action(act->u.block_dirty_bitmap_enable.data,
2172                                          tran, errp);
2173         return;
2174     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_DISABLE:
2175         block_dirty_bitmap_disable_action(
2176                 act->u.block_dirty_bitmap_disable.data, tran, errp);
2177         return;
2178     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_MERGE:
2179         block_dirty_bitmap_merge_action(act->u.block_dirty_bitmap_merge.data,
2180                                         tran, errp);
2181         return;
2182     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_REMOVE:
2183         block_dirty_bitmap_remove_action(act->u.block_dirty_bitmap_remove.data,
2184                                          tran, errp);
2185         return;
2186     /*
2187      * Where are transactions for MIRROR, COMMIT and STREAM?
2188      * Although these blockjobs use transaction callbacks like the backup job,
2189      * these jobs do not necessarily adhere to transaction semantics.
2190      * These jobs may not fully undo all of their actions on abort, nor do they
2191      * necessarily work in transactions with more than one job in them.
2192      */
2193     case TRANSACTION_ACTION_KIND__MAX:
2194     default:
2195         g_assert_not_reached();
2196     };
2197 }
2198 
2199 
2200 /*
2201  * 'Atomic' group operations.  The operations are performed as a set, and if
2202  * any fail then we roll back all operations in the group.
2203  *
2204  * Always run under BQL.
2205  */
qmp_transaction(TransactionActionList * actions,struct TransactionProperties * properties,Error ** errp)2206 void qmp_transaction(TransactionActionList *actions,
2207                      struct TransactionProperties *properties,
2208                      Error **errp)
2209 {
2210     TransactionActionList *act;
2211     JobTxn *block_job_txn = NULL;
2212     Error *local_err = NULL;
2213     Transaction *tran;
2214     ActionCompletionMode comp_mode =
2215         properties ? properties->completion_mode :
2216         ACTION_COMPLETION_MODE_INDIVIDUAL;
2217 
2218     GLOBAL_STATE_CODE();
2219 
2220     /* Does this transaction get canceled as a group on failure?
2221      * If not, we don't really need to make a JobTxn.
2222      */
2223     if (comp_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
2224         for (act = actions; act; act = act->next) {
2225             TransactionActionKind type = act->value->type;
2226 
2227             if (type != TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP &&
2228                 type != TRANSACTION_ACTION_KIND_DRIVE_BACKUP)
2229             {
2230                 error_setg(errp,
2231                            "Action '%s' does not support transaction property "
2232                            "completion-mode = %s",
2233                            TransactionActionKind_str(type),
2234                            ActionCompletionMode_str(comp_mode));
2235                 return;
2236             }
2237         }
2238 
2239         block_job_txn = job_txn_new();
2240     }
2241 
2242     /* drain all i/o before any operations */
2243     bdrv_drain_all();
2244 
2245     tran = tran_new();
2246 
2247     /* We don't do anything in this loop that commits us to the operations */
2248     for (act = actions; act; act = act->next) {
2249         transaction_action(act->value, block_job_txn, tran, &local_err);
2250         if (local_err) {
2251             error_propagate(errp, local_err);
2252             goto delete_and_fail;
2253         }
2254     }
2255 
2256     tran_commit(tran);
2257 
2258     /* success */
2259     goto exit;
2260 
2261 delete_and_fail:
2262     /* failure, and it is all-or-none; roll back all operations */
2263     tran_abort(tran);
2264 exit:
2265     job_txn_unref(block_job_txn);
2266 }
2267 
qmp_x_debug_block_dirty_bitmap_sha256(const char * node,const char * name,Error ** errp)2268 BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
2269                                                               const char *name,
2270                                                               Error **errp)
2271 {
2272     BdrvDirtyBitmap *bitmap;
2273     BlockDriverState *bs;
2274     BlockDirtyBitmapSha256 *ret = NULL;
2275     char *sha256;
2276 
2277     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2278     if (!bitmap || !bs) {
2279         return NULL;
2280     }
2281 
2282     sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
2283     if (sha256 == NULL) {
2284         return NULL;
2285     }
2286 
2287     ret = g_new(BlockDirtyBitmapSha256, 1);
2288     ret->sha256 = sha256;
2289 
2290     return ret;
2291 }
2292 
qmp_block_resize(const char * device,const char * node_name,int64_t size,Error ** errp)2293 void coroutine_fn qmp_block_resize(const char *device, const char *node_name,
2294                                    int64_t size, Error **errp)
2295 {
2296     Error *local_err = NULL;
2297     BlockBackend *blk;
2298     BlockDriverState *bs;
2299     AioContext *old_ctx;
2300 
2301     bs = bdrv_lookup_bs(device, node_name, &local_err);
2302     if (local_err) {
2303         error_propagate(errp, local_err);
2304         return;
2305     }
2306 
2307     if (size < 0) {
2308         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
2309         return;
2310     }
2311 
2312     bdrv_graph_co_rdlock();
2313     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, errp)) {
2314         bdrv_graph_co_rdunlock();
2315         return;
2316     }
2317     bdrv_graph_co_rdunlock();
2318 
2319     blk = blk_co_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
2320     if (!blk) {
2321         return;
2322     }
2323 
2324     bdrv_drained_begin(bs);
2325 
2326     old_ctx = bdrv_co_enter(bs);
2327     blk_co_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
2328     bdrv_co_leave(bs, old_ctx);
2329 
2330     bdrv_drained_end(bs);
2331     blk_co_unref(blk);
2332 }
2333 
qmp_block_stream(const char * job_id,const char * device,const char * base,const char * base_node,const char * backing_file,bool has_backing_mask_protocol,bool backing_mask_protocol,const char * bottom,bool has_speed,int64_t speed,bool has_on_error,BlockdevOnError on_error,const char * filter_node_name,bool has_auto_finalize,bool auto_finalize,bool has_auto_dismiss,bool auto_dismiss,Error ** errp)2334 void qmp_block_stream(const char *job_id, const char *device,
2335                       const char *base,
2336                       const char *base_node,
2337                       const char *backing_file,
2338                       bool has_backing_mask_protocol,
2339                       bool backing_mask_protocol,
2340                       const char *bottom,
2341                       bool has_speed, int64_t speed,
2342                       bool has_on_error, BlockdevOnError on_error,
2343                       const char *filter_node_name,
2344                       bool has_auto_finalize, bool auto_finalize,
2345                       bool has_auto_dismiss, bool auto_dismiss,
2346                       Error **errp)
2347 {
2348     BlockDriverState *bs, *iter, *iter_end;
2349     BlockDriverState *base_bs = NULL;
2350     BlockDriverState *bottom_bs = NULL;
2351     AioContext *aio_context;
2352     Error *local_err = NULL;
2353     int job_flags = JOB_DEFAULT;
2354 
2355     GLOBAL_STATE_CODE();
2356 
2357     if (base && base_node) {
2358         error_setg(errp, "'base' and 'base-node' cannot be specified "
2359                    "at the same time");
2360         return;
2361     }
2362 
2363     if (base && bottom) {
2364         error_setg(errp, "'base' and 'bottom' cannot be specified "
2365                    "at the same time");
2366         return;
2367     }
2368 
2369     if (bottom && base_node) {
2370         error_setg(errp, "'bottom' and 'base-node' cannot be specified "
2371                    "at the same time");
2372         return;
2373     }
2374 
2375     if (!has_backing_mask_protocol) {
2376         backing_mask_protocol = false;
2377     }
2378 
2379     if (!has_on_error) {
2380         on_error = BLOCKDEV_ON_ERROR_REPORT;
2381     }
2382 
2383     bs = bdrv_lookup_bs(device, device, errp);
2384     if (!bs) {
2385         return;
2386     }
2387 
2388     aio_context = bdrv_get_aio_context(bs);
2389 
2390     bdrv_graph_rdlock_main_loop();
2391     if (base) {
2392         base_bs = bdrv_find_backing_image(bs, base);
2393         if (base_bs == NULL) {
2394             error_setg(errp, "Can't find '%s' in the backing chain", base);
2395             goto out_rdlock;
2396         }
2397         assert(bdrv_get_aio_context(base_bs) == aio_context);
2398     }
2399 
2400     if (base_node) {
2401         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2402         if (!base_bs) {
2403             goto out_rdlock;
2404         }
2405         if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
2406             error_setg(errp, "Node '%s' is not a backing image of '%s'",
2407                        base_node, device);
2408             goto out_rdlock;
2409         }
2410         assert(bdrv_get_aio_context(base_bs) == aio_context);
2411 
2412         bdrv_refresh_filename(base_bs);
2413     }
2414 
2415     if (bottom) {
2416         bottom_bs = bdrv_lookup_bs(NULL, bottom, errp);
2417         if (!bottom_bs) {
2418             goto out_rdlock;
2419         }
2420         if (!bottom_bs->drv) {
2421             error_setg(errp, "Node '%s' is not open", bottom);
2422             goto out_rdlock;
2423         }
2424         if (bottom_bs->drv->is_filter) {
2425             error_setg(errp, "Node '%s' is a filter, use a non-filter node "
2426                        "as 'bottom'", bottom);
2427             goto out_rdlock;
2428         }
2429         if (!bdrv_chain_contains(bs, bottom_bs)) {
2430             error_setg(errp, "Node '%s' is not in a chain starting from '%s'",
2431                        bottom, device);
2432             goto out_rdlock;
2433         }
2434         assert(bdrv_get_aio_context(bottom_bs) == aio_context);
2435     }
2436 
2437     /*
2438      * Check for op blockers in the whole chain between bs and base (or bottom)
2439      */
2440     iter_end = bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
2441     for (iter = bs; iter && iter != iter_end;
2442          iter = bdrv_filter_or_cow_bs(iter))
2443     {
2444         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
2445             goto out_rdlock;
2446         }
2447     }
2448     bdrv_graph_rdunlock_main_loop();
2449 
2450     /* if we are streaming the entire chain, the result will have no backing
2451      * file, and specifying one is therefore an error */
2452     if (!base_bs && backing_file) {
2453         error_setg(errp, "backing file specified, but streaming the "
2454                          "entire chain");
2455         return;
2456     }
2457 
2458     if (has_auto_finalize && !auto_finalize) {
2459         job_flags |= JOB_MANUAL_FINALIZE;
2460     }
2461     if (has_auto_dismiss && !auto_dismiss) {
2462         job_flags |= JOB_MANUAL_DISMISS;
2463     }
2464 
2465     stream_start(job_id, bs, base_bs, backing_file,
2466                  backing_mask_protocol,
2467                  bottom_bs, job_flags, has_speed ? speed : 0, on_error,
2468                  filter_node_name, &local_err);
2469     if (local_err) {
2470         error_propagate(errp, local_err);
2471         return;
2472     }
2473 
2474     trace_qmp_block_stream(bs);
2475     return;
2476 
2477 out_rdlock:
2478     bdrv_graph_rdunlock_main_loop();
2479 }
2480 
qmp_block_commit(const char * job_id,const char * device,const char * base_node,const char * base,const char * top_node,const char * top,const char * backing_file,bool has_backing_mask_protocol,bool backing_mask_protocol,bool has_speed,int64_t speed,bool has_on_error,BlockdevOnError on_error,const char * filter_node_name,bool has_auto_finalize,bool auto_finalize,bool has_auto_dismiss,bool auto_dismiss,Error ** errp)2481 void qmp_block_commit(const char *job_id, const char *device,
2482                       const char *base_node,
2483                       const char *base,
2484                       const char *top_node,
2485                       const char *top,
2486                       const char *backing_file,
2487                       bool has_backing_mask_protocol,
2488                       bool backing_mask_protocol,
2489                       bool has_speed, int64_t speed,
2490                       bool has_on_error, BlockdevOnError on_error,
2491                       const char *filter_node_name,
2492                       bool has_auto_finalize, bool auto_finalize,
2493                       bool has_auto_dismiss, bool auto_dismiss,
2494                       Error **errp)
2495 {
2496     BlockDriverState *bs;
2497     BlockDriverState *iter;
2498     BlockDriverState *base_bs, *top_bs;
2499     AioContext *aio_context;
2500     Error *local_err = NULL;
2501     int job_flags = JOB_DEFAULT;
2502     uint64_t top_perm, top_shared;
2503 
2504     /* TODO We'll eventually have to take a writer lock in this function */
2505     GRAPH_RDLOCK_GUARD_MAINLOOP();
2506 
2507     if (!has_speed) {
2508         speed = 0;
2509     }
2510     if (!has_on_error) {
2511         on_error = BLOCKDEV_ON_ERROR_REPORT;
2512     }
2513     if (has_auto_finalize && !auto_finalize) {
2514         job_flags |= JOB_MANUAL_FINALIZE;
2515     }
2516     if (has_auto_dismiss && !auto_dismiss) {
2517         job_flags |= JOB_MANUAL_DISMISS;
2518     }
2519     if (!has_backing_mask_protocol) {
2520         backing_mask_protocol = false;
2521     }
2522 
2523     /* Important Note:
2524      *  libvirt relies on the DeviceNotFound error class in order to probe for
2525      *  live commit feature versions; for this to work, we must make sure to
2526      *  perform the device lookup before any generic errors that may occur in a
2527      *  scenario in which all optional arguments are omitted. */
2528     bs = qmp_get_root_bs(device, &local_err);
2529     if (!bs) {
2530         bs = bdrv_lookup_bs(device, device, NULL);
2531         if (!bs) {
2532             error_free(local_err);
2533             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
2534                       "Device '%s' not found", device);
2535         } else {
2536             error_propagate(errp, local_err);
2537         }
2538         return;
2539     }
2540 
2541     aio_context = bdrv_get_aio_context(bs);
2542 
2543     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
2544         return;
2545     }
2546 
2547     /* default top_bs is the active layer */
2548     top_bs = bs;
2549 
2550     if (top_node && top) {
2551         error_setg(errp, "'top-node' and 'top' are mutually exclusive");
2552         return;
2553     } else if (top_node) {
2554         top_bs = bdrv_lookup_bs(NULL, top_node, errp);
2555         if (top_bs == NULL) {
2556             return;
2557         }
2558         if (!bdrv_chain_contains(bs, top_bs)) {
2559             error_setg(errp, "'%s' is not in this backing file chain",
2560                        top_node);
2561             return;
2562         }
2563     } else if (top) {
2564         /* This strcmp() is just a shortcut, there is no need to
2565          * refresh @bs's filename.  If it mismatches,
2566          * bdrv_find_backing_image() will do the refresh and may still
2567          * return @bs. */
2568         if (strcmp(bs->filename, top) != 0) {
2569             top_bs = bdrv_find_backing_image(bs, top);
2570         }
2571     }
2572 
2573     if (top_bs == NULL) {
2574         error_setg(errp, "Top image file %s not found", top ? top : "NULL");
2575         return;
2576     }
2577 
2578     assert(bdrv_get_aio_context(top_bs) == aio_context);
2579 
2580     if (base_node && base) {
2581         error_setg(errp, "'base-node' and 'base' are mutually exclusive");
2582         return;
2583     } else if (base_node) {
2584         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2585         if (base_bs == NULL) {
2586             return;
2587         }
2588         if (!bdrv_chain_contains(top_bs, base_bs)) {
2589             error_setg(errp, "'%s' is not in this backing file chain",
2590                        base_node);
2591             return;
2592         }
2593     } else if (base) {
2594         base_bs = bdrv_find_backing_image(top_bs, base);
2595         if (base_bs == NULL) {
2596             error_setg(errp, "Can't find '%s' in the backing chain", base);
2597             return;
2598         }
2599     } else {
2600         base_bs = bdrv_find_base(top_bs);
2601         if (base_bs == NULL) {
2602             error_setg(errp, "There is no backimg image");
2603             return;
2604         }
2605     }
2606 
2607     assert(bdrv_get_aio_context(base_bs) == aio_context);
2608 
2609     for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
2610          iter = bdrv_filter_or_cow_bs(iter))
2611     {
2612         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2613             return;
2614         }
2615     }
2616 
2617     /* Do not allow attempts to commit an image into itself */
2618     if (top_bs == base_bs) {
2619         error_setg(errp, "cannot commit an image into itself");
2620         return;
2621     }
2622 
2623     /*
2624      * Active commit is required if and only if someone has taken a
2625      * WRITE permission on the top node.  Historically, we have always
2626      * used active commit for top nodes, so continue that practice
2627      * lest we possibly break clients that rely on this behavior, e.g.
2628      * to later attach this node to a writing parent.
2629      * (Active commit is never really wrong.)
2630      */
2631     bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared);
2632     if (top_perm & BLK_PERM_WRITE ||
2633         bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs))
2634     {
2635         if (backing_file) {
2636             if (bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs)) {
2637                 error_setg(errp, "'backing-file' specified,"
2638                                  " but 'top' is the active layer");
2639             } else {
2640                 error_setg(errp, "'backing-file' specified, but 'top' has a "
2641                                  "writer on it");
2642             }
2643             return;
2644         }
2645         if (!job_id) {
2646             /*
2647              * Emulate here what block_job_create() does, because it
2648              * is possible that @bs != @top_bs (the block job should
2649              * be named after @bs, even if @top_bs is the actual
2650              * source)
2651              */
2652             job_id = bdrv_get_device_name(bs);
2653         }
2654         commit_active_start(job_id, top_bs, base_bs, job_flags, speed, on_error,
2655                             filter_node_name, NULL, NULL, false, &local_err);
2656     } else {
2657         BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
2658         if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2659             return;
2660         }
2661         commit_start(job_id, bs, base_bs, top_bs, job_flags,
2662                      speed, on_error, backing_file,
2663                      backing_mask_protocol,
2664                      filter_node_name, &local_err);
2665     }
2666     if (local_err != NULL) {
2667         error_propagate(errp, local_err);
2668         return;
2669     }
2670 }
2671 
2672 /* Common QMP interface for drive-backup and blockdev-backup */
do_backup_common(BackupCommon * backup,BlockDriverState * bs,BlockDriverState * target_bs,AioContext * aio_context,JobTxn * txn,Error ** errp)2673 static BlockJob *do_backup_common(BackupCommon *backup,
2674                                   BlockDriverState *bs,
2675                                   BlockDriverState *target_bs,
2676                                   AioContext *aio_context,
2677                                   JobTxn *txn, Error **errp)
2678 {
2679     BlockJob *job = NULL;
2680     BdrvDirtyBitmap *bmap = NULL;
2681     BackupPerf perf = { .max_workers = 64 };
2682     int job_flags = JOB_DEFAULT;
2683     OnCbwError on_cbw_error = ON_CBW_ERROR_BREAK_GUEST_WRITE;
2684 
2685     if (!backup->has_speed) {
2686         backup->speed = 0;
2687     }
2688     if (!backup->has_on_source_error) {
2689         backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2690     }
2691     if (!backup->has_on_target_error) {
2692         backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2693     }
2694     if (!backup->has_auto_finalize) {
2695         backup->auto_finalize = true;
2696     }
2697     if (!backup->has_auto_dismiss) {
2698         backup->auto_dismiss = true;
2699     }
2700     if (!backup->has_compress) {
2701         backup->compress = false;
2702     }
2703 
2704     if (backup->x_perf) {
2705         if (backup->x_perf->has_use_copy_range) {
2706             perf.use_copy_range = backup->x_perf->use_copy_range;
2707         }
2708         if (backup->x_perf->has_max_workers) {
2709             perf.max_workers = backup->x_perf->max_workers;
2710         }
2711         if (backup->x_perf->has_max_chunk) {
2712             perf.max_chunk = backup->x_perf->max_chunk;
2713         }
2714         if (backup->x_perf->has_min_cluster_size) {
2715             perf.min_cluster_size = backup->x_perf->min_cluster_size;
2716         }
2717     }
2718 
2719     if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) ||
2720         (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL)) {
2721         /* done before desugaring 'incremental' to print the right message */
2722         if (!backup->bitmap) {
2723             error_setg(errp, "must provide a valid bitmap name for "
2724                        "'%s' sync mode", MirrorSyncMode_str(backup->sync));
2725             return NULL;
2726         }
2727     }
2728 
2729     if (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL) {
2730         if (backup->has_bitmap_mode &&
2731             backup->bitmap_mode != BITMAP_SYNC_MODE_ON_SUCCESS) {
2732             error_setg(errp, "Bitmap sync mode must be '%s' "
2733                        "when using sync mode '%s'",
2734                        BitmapSyncMode_str(BITMAP_SYNC_MODE_ON_SUCCESS),
2735                        MirrorSyncMode_str(backup->sync));
2736             return NULL;
2737         }
2738         backup->has_bitmap_mode = true;
2739         backup->sync = MIRROR_SYNC_MODE_BITMAP;
2740         backup->bitmap_mode = BITMAP_SYNC_MODE_ON_SUCCESS;
2741     }
2742 
2743     if (backup->bitmap) {
2744         bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
2745         if (!bmap) {
2746             error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
2747             return NULL;
2748         }
2749         if (!backup->has_bitmap_mode) {
2750             error_setg(errp, "Bitmap sync mode must be given "
2751                        "when providing a bitmap");
2752             return NULL;
2753         }
2754         if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2755             return NULL;
2756         }
2757 
2758         /* This does not produce a useful bitmap artifact: */
2759         if (backup->sync == MIRROR_SYNC_MODE_NONE) {
2760             error_setg(errp, "sync mode '%s' does not produce meaningful bitmap"
2761                        " outputs", MirrorSyncMode_str(backup->sync));
2762             return NULL;
2763         }
2764 
2765         /* If the bitmap isn't used for input or output, this is useless: */
2766         if (backup->bitmap_mode == BITMAP_SYNC_MODE_NEVER &&
2767             backup->sync != MIRROR_SYNC_MODE_BITMAP) {
2768             error_setg(errp, "Bitmap sync mode '%s' has no meaningful effect"
2769                        " when combined with sync mode '%s'",
2770                        BitmapSyncMode_str(backup->bitmap_mode),
2771                        MirrorSyncMode_str(backup->sync));
2772             return NULL;
2773         }
2774     }
2775 
2776     if (!backup->bitmap && backup->has_bitmap_mode) {
2777         error_setg(errp, "Cannot specify bitmap sync mode without a bitmap");
2778         return NULL;
2779     }
2780 
2781     if (!backup->auto_finalize) {
2782         job_flags |= JOB_MANUAL_FINALIZE;
2783     }
2784     if (!backup->auto_dismiss) {
2785         job_flags |= JOB_MANUAL_DISMISS;
2786     }
2787 
2788     if (backup->has_on_cbw_error) {
2789         on_cbw_error = backup->on_cbw_error;
2790     }
2791 
2792     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
2793                             backup->sync, bmap, backup->bitmap_mode,
2794                             backup->compress, backup->discard_source,
2795                             backup->filter_node_name,
2796                             &perf,
2797                             backup->on_source_error,
2798                             backup->on_target_error,
2799                             on_cbw_error,
2800                             job_flags, NULL, NULL, txn, errp);
2801     return job;
2802 }
2803 
qmp_drive_backup(DriveBackup * backup,Error ** errp)2804 void qmp_drive_backup(DriveBackup *backup, Error **errp)
2805 {
2806     TransactionAction action = {
2807         .type = TRANSACTION_ACTION_KIND_DRIVE_BACKUP,
2808         .u.drive_backup.data = backup,
2809     };
2810     blockdev_do_action(&action, errp);
2811 }
2812 
qmp_query_named_block_nodes(bool has_flat,bool flat,Error ** errp)2813 BlockDeviceInfoList *qmp_query_named_block_nodes(bool has_flat,
2814                                                  bool flat,
2815                                                  Error **errp)
2816 {
2817     bool return_flat = has_flat && flat;
2818 
2819     return bdrv_named_nodes_list(return_flat, errp);
2820 }
2821 
qmp_x_debug_query_block_graph(Error ** errp)2822 XDbgBlockGraph *qmp_x_debug_query_block_graph(Error **errp)
2823 {
2824     GRAPH_RDLOCK_GUARD_MAINLOOP();
2825 
2826     return bdrv_get_xdbg_block_graph(errp);
2827 }
2828 
qmp_blockdev_backup(BlockdevBackup * backup,Error ** errp)2829 void qmp_blockdev_backup(BlockdevBackup *backup, Error **errp)
2830 {
2831     TransactionAction action = {
2832         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP,
2833         .u.blockdev_backup.data = backup,
2834     };
2835     blockdev_do_action(&action, errp);
2836 }
2837 
2838 /* Parameter check and block job starting for drive mirroring.
2839  * Caller should hold @device and @target's aio context (must be the same).
2840  **/
blockdev_mirror_common(const char * job_id,BlockDriverState * bs,BlockDriverState * target,const char * replaces,enum MirrorSyncMode sync,BlockMirrorBackingMode backing_mode,bool target_is_zero,bool has_speed,int64_t speed,bool has_granularity,uint32_t granularity,bool has_buf_size,int64_t buf_size,bool has_on_source_error,BlockdevOnError on_source_error,bool has_on_target_error,BlockdevOnError on_target_error,bool has_unmap,bool unmap,const char * filter_node_name,bool has_copy_mode,MirrorCopyMode copy_mode,bool has_auto_finalize,bool auto_finalize,bool has_auto_dismiss,bool auto_dismiss,Error ** errp)2841 static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
2842                                    BlockDriverState *target,
2843                                    const char *replaces,
2844                                    enum MirrorSyncMode sync,
2845                                    BlockMirrorBackingMode backing_mode,
2846                                    bool target_is_zero,
2847                                    bool has_speed, int64_t speed,
2848                                    bool has_granularity, uint32_t granularity,
2849                                    bool has_buf_size, int64_t buf_size,
2850                                    bool has_on_source_error,
2851                                    BlockdevOnError on_source_error,
2852                                    bool has_on_target_error,
2853                                    BlockdevOnError on_target_error,
2854                                    bool has_unmap, bool unmap,
2855                                    const char *filter_node_name,
2856                                    bool has_copy_mode, MirrorCopyMode copy_mode,
2857                                    bool has_auto_finalize, bool auto_finalize,
2858                                    bool has_auto_dismiss, bool auto_dismiss,
2859                                    Error **errp)
2860 {
2861     BlockDriverState *unfiltered_bs;
2862     int job_flags = JOB_DEFAULT;
2863 
2864     GLOBAL_STATE_CODE();
2865     GRAPH_RDLOCK_GUARD_MAINLOOP();
2866 
2867     if (!has_speed) {
2868         speed = 0;
2869     }
2870     if (!has_on_source_error) {
2871         on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2872     }
2873     if (!has_on_target_error) {
2874         on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2875     }
2876     if (!has_granularity) {
2877         granularity = 0;
2878     }
2879     if (!has_buf_size) {
2880         buf_size = 0;
2881     }
2882     if (!has_unmap) {
2883         unmap = true;
2884     }
2885     if (!has_copy_mode) {
2886         copy_mode = MIRROR_COPY_MODE_BACKGROUND;
2887     }
2888     if (has_auto_finalize && !auto_finalize) {
2889         job_flags |= JOB_MANUAL_FINALIZE;
2890     }
2891     if (has_auto_dismiss && !auto_dismiss) {
2892         job_flags |= JOB_MANUAL_DISMISS;
2893     }
2894 
2895     if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
2896         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2897                    "a value in range [512B, 64MB]");
2898         return;
2899     }
2900     if (granularity & (granularity - 1)) {
2901         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2902                    "a power of 2");
2903         return;
2904     }
2905 
2906     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2907         return;
2908     }
2909     if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
2910         return;
2911     }
2912 
2913     if (!replaces) {
2914         /* We want to mirror from @bs, but keep implicit filters on top */
2915         unfiltered_bs = bdrv_skip_implicit_filters(bs);
2916         if (unfiltered_bs != bs) {
2917             replaces = unfiltered_bs->node_name;
2918         }
2919     }
2920 
2921     if (replaces) {
2922         BlockDriverState *to_replace_bs;
2923         int64_t bs_size, replace_size;
2924 
2925         bs_size = bdrv_getlength(bs);
2926         if (bs_size < 0) {
2927             error_setg_errno(errp, -bs_size, "Failed to query device's size");
2928             return;
2929         }
2930 
2931         to_replace_bs = check_to_replace_node(bs, replaces, errp);
2932         if (!to_replace_bs) {
2933             return;
2934         }
2935 
2936         replace_size = bdrv_getlength(to_replace_bs);
2937 
2938         if (replace_size < 0) {
2939             error_setg_errno(errp, -replace_size,
2940                              "Failed to query the replacement node's size");
2941             return;
2942         }
2943         if (bs_size != replace_size) {
2944             error_setg(errp, "cannot replace image with a mirror image of "
2945                              "different size");
2946             return;
2947         }
2948     }
2949 
2950     /* pass the node name to replace to mirror start since it's loose coupling
2951      * and will allow to check whether the node still exist at mirror completion
2952      */
2953     mirror_start(job_id, bs, target, replaces, job_flags,
2954                  speed, granularity, buf_size, sync, backing_mode,
2955                  target_is_zero, on_source_error, on_target_error, unmap,
2956                  filter_node_name, copy_mode, errp);
2957 }
2958 
qmp_drive_mirror(DriveMirror * arg,Error ** errp)2959 void qmp_drive_mirror(DriveMirror *arg, Error **errp)
2960 {
2961     BlockDriverState *bs;
2962     BlockDriverState *target_backing_bs, *target_bs;
2963     AioContext *aio_context;
2964     BlockMirrorBackingMode backing_mode;
2965     Error *local_err = NULL;
2966     QDict *options = NULL;
2967     int flags;
2968     int64_t size;
2969     const char *format = arg->format;
2970     bool target_is_zero;
2971     int ret;
2972 
2973     bs = qmp_get_root_bs(arg->device, errp);
2974     if (!bs) {
2975         return;
2976     }
2977 
2978     /* Early check to avoid creating target */
2979     bdrv_graph_rdlock_main_loop();
2980     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2981         bdrv_graph_rdunlock_main_loop();
2982         return;
2983     }
2984 
2985     aio_context = bdrv_get_aio_context(bs);
2986 
2987     if (!arg->has_mode) {
2988         arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
2989     }
2990 
2991     if (!arg->format) {
2992         format = (arg->mode == NEW_IMAGE_MODE_EXISTING
2993                   ? NULL : bs->drv->format_name);
2994     }
2995 
2996     flags = bs->open_flags | BDRV_O_RDWR;
2997     target_backing_bs = bdrv_cow_bs(bdrv_skip_filters(bs));
2998     if (!target_backing_bs && arg->sync == MIRROR_SYNC_MODE_TOP) {
2999         arg->sync = MIRROR_SYNC_MODE_FULL;
3000     }
3001     if (arg->sync == MIRROR_SYNC_MODE_NONE) {
3002         target_backing_bs = bs;
3003     }
3004     bdrv_graph_rdunlock_main_loop();
3005 
3006     size = bdrv_getlength(bs);
3007     if (size < 0) {
3008         error_setg_errno(errp, -size, "bdrv_getlength failed");
3009         return;
3010     }
3011 
3012     if (arg->replaces) {
3013         if (!arg->node_name) {
3014             error_setg(errp, "a node-name must be provided when replacing a"
3015                              " named node of the graph");
3016             return;
3017         }
3018     }
3019 
3020     if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
3021         backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
3022     } else {
3023         backing_mode = MIRROR_OPEN_BACKING_CHAIN;
3024     }
3025 
3026     /* Don't open backing image in create() */
3027     flags |= BDRV_O_NO_BACKING;
3028 
3029     if ((arg->sync == MIRROR_SYNC_MODE_FULL || !target_backing_bs)
3030         && arg->mode != NEW_IMAGE_MODE_EXISTING)
3031     {
3032         /* create new image w/o backing file */
3033         assert(format);
3034         bdrv_img_create(arg->target, format,
3035                         NULL, NULL, NULL, size, flags, false, &local_err);
3036     } else {
3037         BlockDriverState *explicit_backing;
3038 
3039         switch (arg->mode) {
3040         case NEW_IMAGE_MODE_EXISTING:
3041             break;
3042         case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
3043             /*
3044              * Create new image with backing file.
3045              * Implicit filters should not appear in the filename.
3046              */
3047             bdrv_graph_rdlock_main_loop();
3048             explicit_backing = bdrv_skip_implicit_filters(target_backing_bs);
3049             bdrv_refresh_filename(explicit_backing);
3050             bdrv_graph_rdunlock_main_loop();
3051 
3052             bdrv_img_create(arg->target, format,
3053                             explicit_backing->filename,
3054                             explicit_backing->drv->format_name,
3055                             NULL, size, flags, false, &local_err);
3056             break;
3057         default:
3058             abort();
3059         }
3060     }
3061 
3062     if (local_err) {
3063         error_propagate(errp, local_err);
3064         return;
3065     }
3066 
3067     options = qdict_new();
3068     if (arg->node_name) {
3069         qdict_put_str(options, "node-name", arg->node_name);
3070     }
3071     if (format) {
3072         qdict_put_str(options, "driver", format);
3073     }
3074 
3075     /* Mirroring takes care of copy-on-write using the source's backing
3076      * file.
3077      */
3078     target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
3079     if (!target_bs) {
3080         return;
3081     }
3082 
3083     bdrv_graph_rdlock_main_loop();
3084     target_is_zero = (arg->mode != NEW_IMAGE_MODE_EXISTING &&
3085                       bdrv_has_zero_init(target_bs));
3086     bdrv_graph_rdunlock_main_loop();
3087 
3088 
3089     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3090     if (ret < 0) {
3091         bdrv_unref(target_bs);
3092         return;
3093     }
3094 
3095     blockdev_mirror_common(arg->job_id, bs, target_bs,
3096                            arg->replaces, arg->sync,
3097                            backing_mode, target_is_zero,
3098                            arg->has_speed, arg->speed,
3099                            arg->has_granularity, arg->granularity,
3100                            arg->has_buf_size, arg->buf_size,
3101                            arg->has_on_source_error, arg->on_source_error,
3102                            arg->has_on_target_error, arg->on_target_error,
3103                            arg->has_unmap, arg->unmap,
3104                            NULL,
3105                            arg->has_copy_mode, arg->copy_mode,
3106                            arg->has_auto_finalize, arg->auto_finalize,
3107                            arg->has_auto_dismiss, arg->auto_dismiss,
3108                            errp);
3109     bdrv_unref(target_bs);
3110 }
3111 
qmp_blockdev_mirror(const char * job_id,const char * device,const char * target,const char * replaces,MirrorSyncMode sync,bool has_speed,int64_t speed,bool has_granularity,uint32_t granularity,bool has_buf_size,int64_t buf_size,bool has_on_source_error,BlockdevOnError on_source_error,bool has_on_target_error,BlockdevOnError on_target_error,const char * filter_node_name,bool has_copy_mode,MirrorCopyMode copy_mode,bool has_auto_finalize,bool auto_finalize,bool has_auto_dismiss,bool auto_dismiss,bool has_target_is_zero,bool target_is_zero,Error ** errp)3112 void qmp_blockdev_mirror(const char *job_id,
3113                          const char *device, const char *target,
3114                          const char *replaces,
3115                          MirrorSyncMode sync,
3116                          bool has_speed, int64_t speed,
3117                          bool has_granularity, uint32_t granularity,
3118                          bool has_buf_size, int64_t buf_size,
3119                          bool has_on_source_error,
3120                          BlockdevOnError on_source_error,
3121                          bool has_on_target_error,
3122                          BlockdevOnError on_target_error,
3123                          const char *filter_node_name,
3124                          bool has_copy_mode, MirrorCopyMode copy_mode,
3125                          bool has_auto_finalize, bool auto_finalize,
3126                          bool has_auto_dismiss, bool auto_dismiss,
3127                          bool has_target_is_zero, bool target_is_zero,
3128                          Error **errp)
3129 {
3130     BlockDriverState *bs;
3131     BlockDriverState *target_bs;
3132     AioContext *aio_context;
3133     BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
3134     int ret;
3135 
3136     bs = qmp_get_root_bs(device, errp);
3137     if (!bs) {
3138         return;
3139     }
3140 
3141     target_bs = bdrv_lookup_bs(target, target, errp);
3142     if (!target_bs) {
3143         return;
3144     }
3145 
3146     aio_context = bdrv_get_aio_context(bs);
3147 
3148     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3149     if (ret < 0) {
3150         return;
3151     }
3152 
3153     blockdev_mirror_common(job_id, bs, target_bs,
3154                            replaces, sync, backing_mode,
3155                            has_target_is_zero && target_is_zero,
3156                            has_speed, speed,
3157                            has_granularity, granularity,
3158                            has_buf_size, buf_size,
3159                            has_on_source_error, on_source_error,
3160                            has_on_target_error, on_target_error,
3161                            true, true, filter_node_name,
3162                            has_copy_mode, copy_mode,
3163                            has_auto_finalize, auto_finalize,
3164                            has_auto_dismiss, auto_dismiss,
3165                            errp);
3166 }
3167 
3168 /*
3169  * Get a block job using its ID. Called with job_mutex held.
3170  */
find_block_job_locked(const char * id,Error ** errp)3171 static BlockJob *find_block_job_locked(const char *id, Error **errp)
3172 {
3173     BlockJob *job;
3174 
3175     assert(id != NULL);
3176 
3177     job = block_job_get_locked(id);
3178 
3179     if (!job) {
3180         error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
3181                   "Block job '%s' not found", id);
3182         return NULL;
3183     }
3184 
3185     return job;
3186 }
3187 
qmp_block_job_set_speed(const char * device,int64_t speed,Error ** errp)3188 void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
3189 {
3190     BlockJob *job;
3191 
3192     JOB_LOCK_GUARD();
3193     job = find_block_job_locked(device, errp);
3194 
3195     if (!job) {
3196         return;
3197     }
3198 
3199     block_job_set_speed_locked(job, speed, errp);
3200 }
3201 
qmp_block_job_cancel(const char * device,bool has_force,bool force,Error ** errp)3202 void qmp_block_job_cancel(const char *device,
3203                           bool has_force, bool force, Error **errp)
3204 {
3205     BlockJob *job;
3206 
3207     JOB_LOCK_GUARD();
3208     job = find_block_job_locked(device, errp);
3209 
3210     if (!job) {
3211         return;
3212     }
3213 
3214     if (!has_force) {
3215         force = false;
3216     }
3217 
3218     if (job_user_paused_locked(&job->job) && !force) {
3219         error_setg(errp, "The block job for device '%s' is currently paused",
3220                    device);
3221         return;
3222     }
3223 
3224     trace_qmp_block_job_cancel(job);
3225     job_user_cancel_locked(&job->job, force, errp);
3226 }
3227 
qmp_block_job_pause(const char * device,Error ** errp)3228 void qmp_block_job_pause(const char *device, Error **errp)
3229 {
3230     BlockJob *job;
3231 
3232     JOB_LOCK_GUARD();
3233     job = find_block_job_locked(device, errp);
3234 
3235     if (!job) {
3236         return;
3237     }
3238 
3239     trace_qmp_block_job_pause(job);
3240     job_user_pause_locked(&job->job, errp);
3241 }
3242 
qmp_block_job_resume(const char * device,Error ** errp)3243 void qmp_block_job_resume(const char *device, Error **errp)
3244 {
3245     BlockJob *job;
3246 
3247     JOB_LOCK_GUARD();
3248     job = find_block_job_locked(device, errp);
3249 
3250     if (!job) {
3251         return;
3252     }
3253 
3254     trace_qmp_block_job_resume(job);
3255     job_user_resume_locked(&job->job, errp);
3256 }
3257 
qmp_block_job_complete(const char * device,Error ** errp)3258 void qmp_block_job_complete(const char *device, Error **errp)
3259 {
3260     BlockJob *job;
3261 
3262     JOB_LOCK_GUARD();
3263     job = find_block_job_locked(device, errp);
3264 
3265     if (!job) {
3266         return;
3267     }
3268 
3269     trace_qmp_block_job_complete(job);
3270     job_complete_locked(&job->job, errp);
3271 }
3272 
qmp_block_job_finalize(const char * id,Error ** errp)3273 void qmp_block_job_finalize(const char *id, Error **errp)
3274 {
3275     BlockJob *job;
3276 
3277     JOB_LOCK_GUARD();
3278     job = find_block_job_locked(id, errp);
3279 
3280     if (!job) {
3281         return;
3282     }
3283 
3284     trace_qmp_block_job_finalize(job);
3285     job_ref_locked(&job->job);
3286     job_finalize_locked(&job->job, errp);
3287 
3288     job_unref_locked(&job->job);
3289 }
3290 
qmp_block_job_dismiss(const char * id,Error ** errp)3291 void qmp_block_job_dismiss(const char *id, Error **errp)
3292 {
3293     BlockJob *bjob;
3294     Job *job;
3295 
3296     JOB_LOCK_GUARD();
3297     bjob = find_block_job_locked(id, errp);
3298 
3299     if (!bjob) {
3300         return;
3301     }
3302 
3303     trace_qmp_block_job_dismiss(bjob);
3304     job = &bjob->job;
3305     job_dismiss_locked(&job, errp);
3306 }
3307 
qmp_block_job_change(BlockJobChangeOptions * opts,Error ** errp)3308 void qmp_block_job_change(BlockJobChangeOptions *opts, Error **errp)
3309 {
3310     BlockJob *job;
3311 
3312     JOB_LOCK_GUARD();
3313     job = find_block_job_locked(opts->id, errp);
3314 
3315     if (!job) {
3316         return;
3317     }
3318 
3319     block_job_change_locked(job, opts, errp);
3320 }
3321 
qmp_change_backing_file(const char * device,const char * image_node_name,const char * backing_file,Error ** errp)3322 void qmp_change_backing_file(const char *device,
3323                              const char *image_node_name,
3324                              const char *backing_file,
3325                              Error **errp)
3326 {
3327     BlockDriverState *bs = NULL;
3328     BlockDriverState *image_bs = NULL;
3329     Error *local_err = NULL;
3330     bool ro;
3331     int ret;
3332 
3333     bs = qmp_get_root_bs(device, errp);
3334     if (!bs) {
3335         return;
3336     }
3337 
3338     bdrv_graph_rdlock_main_loop();
3339 
3340     image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
3341     if (local_err) {
3342         error_propagate(errp, local_err);
3343         goto out_rdlock;
3344     }
3345 
3346     if (!image_bs) {
3347         error_setg(errp, "image file not found");
3348         goto out_rdlock;
3349     }
3350 
3351     if (bdrv_find_base(image_bs) == image_bs) {
3352         error_setg(errp, "not allowing backing file change on an image "
3353                          "without a backing file");
3354         goto out_rdlock;
3355     }
3356 
3357     /* even though we are not necessarily operating on bs, we need it to
3358      * determine if block ops are currently prohibited on the chain */
3359     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
3360         goto out_rdlock;
3361     }
3362 
3363     /* final sanity check */
3364     if (!bdrv_chain_contains(bs, image_bs)) {
3365         error_setg(errp, "'%s' and image file are not in the same chain",
3366                    device);
3367         goto out_rdlock;
3368     }
3369     bdrv_graph_rdunlock_main_loop();
3370 
3371     /* if not r/w, reopen to make r/w */
3372     ro = bdrv_is_read_only(image_bs);
3373 
3374     if (ro) {
3375         if (bdrv_reopen_set_read_only(image_bs, false, errp) != 0) {
3376             return;
3377         }
3378     }
3379 
3380     ret = bdrv_change_backing_file(image_bs, backing_file,
3381                                    image_bs->drv ? image_bs->drv->format_name : "",
3382                                    false);
3383 
3384     if (ret < 0) {
3385         error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
3386                          backing_file);
3387         /* don't exit here, so we can try to restore open flags if
3388          * appropriate */
3389     }
3390 
3391     if (ro) {
3392         bdrv_reopen_set_read_only(image_bs, true, errp);
3393     }
3394     return;
3395 
3396 out_rdlock:
3397     bdrv_graph_rdunlock_main_loop();
3398 }
3399 
qmp_blockdev_add(BlockdevOptions * options,Error ** errp)3400 void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
3401 {
3402     BlockDriverState *bs;
3403     QObject *obj;
3404     Visitor *v = qobject_output_visitor_new(&obj);
3405     QDict *qdict;
3406 
3407     visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3408     visit_complete(v, &obj);
3409     qdict = qobject_to(QDict, obj);
3410 
3411     qdict_flatten(qdict);
3412 
3413     if (!qdict_get_try_str(qdict, "node-name")) {
3414         error_setg(errp, "'node-name' must be specified for the root node");
3415         goto fail;
3416     }
3417 
3418     bs = bds_tree_init(qdict, errp);
3419     if (!bs) {
3420         goto fail;
3421     }
3422 
3423     bdrv_set_monitor_owned(bs);
3424 
3425 fail:
3426     visit_free(v);
3427 }
3428 
qmp_blockdev_reopen(BlockdevOptionsList * reopen_list,Error ** errp)3429 void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
3430 {
3431     BlockReopenQueue *queue = NULL;
3432 
3433     /* Add each one of the BDS that we want to reopen to the queue */
3434     for (; reopen_list != NULL; reopen_list = reopen_list->next) {
3435         BlockdevOptions *options = reopen_list->value;
3436         BlockDriverState *bs;
3437         QObject *obj;
3438         Visitor *v;
3439         QDict *qdict;
3440 
3441         /* Check for the selected node name */
3442         if (!options->node_name) {
3443             error_setg(errp, "node-name not specified");
3444             goto fail;
3445         }
3446 
3447         bs = bdrv_find_node(options->node_name);
3448         if (!bs) {
3449             error_setg(errp, "Failed to find node with node-name='%s'",
3450                        options->node_name);
3451             goto fail;
3452         }
3453 
3454         /* Put all options in a QDict and flatten it */
3455         v = qobject_output_visitor_new(&obj);
3456         visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3457         visit_complete(v, &obj);
3458         visit_free(v);
3459 
3460         qdict = qobject_to(QDict, obj);
3461 
3462         qdict_flatten(qdict);
3463 
3464         queue = bdrv_reopen_queue(queue, bs, qdict, false);
3465     }
3466 
3467     /* Perform the reopen operation */
3468     bdrv_reopen_multiple(queue, errp);
3469     queue = NULL;
3470 
3471 fail:
3472     bdrv_reopen_queue_free(queue);
3473 }
3474 
qmp_blockdev_del(const char * node_name,Error ** errp)3475 void qmp_blockdev_del(const char *node_name, Error **errp)
3476 {
3477     BlockDriverState *bs;
3478 
3479     GLOBAL_STATE_CODE();
3480     GRAPH_RDLOCK_GUARD_MAINLOOP();
3481 
3482     bs = bdrv_find_node(node_name);
3483     if (!bs) {
3484         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3485         return;
3486     }
3487     if (bdrv_has_blk(bs)) {
3488         error_setg(errp, "Node %s is in use", node_name);
3489         return;
3490     }
3491 
3492     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
3493         return;
3494     }
3495 
3496     if (!QTAILQ_IN_USE(bs, monitor_list)) {
3497         error_setg(errp, "Node %s is not owned by the monitor",
3498                    bs->node_name);
3499         return;
3500     }
3501 
3502     if (bs->refcnt > 1) {
3503         error_setg(errp, "Block device %s is in use",
3504                    bdrv_get_device_or_node_name(bs));
3505         return;
3506     }
3507 
3508     QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
3509     bdrv_unref(bs);
3510 }
3511 
qmp_blockdev_set_active(const char * node_name,bool active,Error ** errp)3512 void qmp_blockdev_set_active(const char *node_name, bool active, Error **errp)
3513 {
3514     int ret;
3515 
3516     GLOBAL_STATE_CODE();
3517     GRAPH_RDLOCK_GUARD_MAINLOOP();
3518 
3519     if (!node_name) {
3520         if (active) {
3521             bdrv_activate_all(errp);
3522         } else {
3523             ret = bdrv_inactivate_all();
3524             if (ret < 0) {
3525                 error_setg_errno(errp, -ret, "Failed to inactivate all nodes");
3526             }
3527         }
3528     } else {
3529         BlockDriverState *bs = bdrv_find_node(node_name);
3530         if (!bs) {
3531             error_setg(errp, "Failed to find node with node-name='%s'",
3532                        node_name);
3533             return;
3534         }
3535 
3536         if (active) {
3537             bdrv_activate(bs, errp);
3538         } else {
3539             bdrv_inactivate(bs, errp);
3540         }
3541     }
3542 }
3543 
3544 static BdrvChild * GRAPH_RDLOCK
bdrv_find_child(BlockDriverState * parent_bs,const char * child_name)3545 bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
3546 {
3547     BdrvChild *child;
3548 
3549     QLIST_FOREACH(child, &parent_bs->children, next) {
3550         if (strcmp(child->name, child_name) == 0) {
3551             return child;
3552         }
3553     }
3554 
3555     return NULL;
3556 }
3557 
qmp_x_blockdev_change(const char * parent,const char * child,const char * node,Error ** errp)3558 void qmp_x_blockdev_change(const char *parent, const char *child,
3559                            const char *node, Error **errp)
3560 {
3561     BlockDriverState *parent_bs, *new_bs = NULL;
3562     BdrvChild *p_child;
3563 
3564     bdrv_drain_all_begin();
3565     bdrv_graph_wrlock();
3566 
3567     parent_bs = bdrv_lookup_bs(parent, parent, errp);
3568     if (!parent_bs) {
3569         goto out;
3570     }
3571 
3572     if (!child == !node) {
3573         if (child) {
3574             error_setg(errp, "The parameters child and node are in conflict");
3575         } else {
3576             error_setg(errp, "Either child or node must be specified");
3577         }
3578         goto out;
3579     }
3580 
3581     if (child) {
3582         p_child = bdrv_find_child(parent_bs, child);
3583         if (!p_child) {
3584             error_setg(errp, "Node '%s' does not have child '%s'",
3585                        parent, child);
3586             goto out;
3587         }
3588         bdrv_del_child(parent_bs, p_child, errp);
3589     }
3590 
3591     if (node) {
3592         new_bs = bdrv_find_node(node);
3593         if (!new_bs) {
3594             error_setg(errp, "Node '%s' not found", node);
3595             goto out;
3596         }
3597         bdrv_add_child(parent_bs, new_bs, errp);
3598     }
3599 
3600 out:
3601     bdrv_graph_wrunlock();
3602     bdrv_drain_all_end();
3603 }
3604 
qmp_query_block_jobs(Error ** errp)3605 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
3606 {
3607     BlockJobInfoList *head = NULL, **tail = &head;
3608     BlockJob *job;
3609 
3610     JOB_LOCK_GUARD();
3611 
3612     for (job = block_job_next_locked(NULL); job;
3613          job = block_job_next_locked(job)) {
3614         BlockJobInfo *value;
3615 
3616         if (block_job_is_internal(job)) {
3617             continue;
3618         }
3619         value = block_job_query_locked(job, errp);
3620         if (!value) {
3621             qapi_free_BlockJobInfoList(head);
3622             return NULL;
3623         }
3624         QAPI_LIST_APPEND(tail, value);
3625     }
3626 
3627     return head;
3628 }
3629 
qmp_x_blockdev_set_iothread(const char * node_name,StrOrNull * iothread,bool has_force,bool force,Error ** errp)3630 void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
3631                                  bool has_force, bool force, Error **errp)
3632 {
3633     AioContext *new_context;
3634     BlockDriverState *bs;
3635 
3636     bdrv_drain_all_begin();
3637     bdrv_graph_rdlock_main_loop();
3638 
3639     bs = bdrv_find_node(node_name);
3640     if (!bs) {
3641         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3642         goto out;
3643     }
3644 
3645     /* Protects against accidents. */
3646     if (!(has_force && force) && bdrv_has_blk(bs)) {
3647         error_setg(errp, "Node %s is associated with a BlockBackend and could "
3648                          "be in use (use force=true to override this check)",
3649                          node_name);
3650         goto out;
3651     }
3652 
3653     if (iothread->type == QTYPE_QSTRING) {
3654         IOThread *obj = iothread_by_id(iothread->u.s);
3655         if (!obj) {
3656             error_setg(errp, "Cannot find iothread %s", iothread->u.s);
3657             goto out;
3658         }
3659 
3660         new_context = iothread_get_aio_context(obj);
3661     } else {
3662         new_context = qemu_get_aio_context();
3663     }
3664 
3665     bdrv_try_change_aio_context_locked(bs, new_context, NULL, errp);
3666 
3667 out:
3668     bdrv_graph_rdunlock_main_loop();
3669     bdrv_drain_all_end();
3670 }
3671 
3672 QemuOptsList qemu_common_drive_opts = {
3673     .name = "drive",
3674     .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
3675     .desc = {
3676         {
3677             .name = "snapshot",
3678             .type = QEMU_OPT_BOOL,
3679             .help = "enable/disable snapshot mode",
3680         },{
3681             .name = "aio",
3682             .type = QEMU_OPT_STRING,
3683             .help = "host AIO implementation (threads, native, io_uring)",
3684         },{
3685             .name = BDRV_OPT_CACHE_WB,
3686             .type = QEMU_OPT_BOOL,
3687             .help = "Enable writeback mode",
3688         },{
3689             .name = "format",
3690             .type = QEMU_OPT_STRING,
3691             .help = "disk format (raw, qcow2, ...)",
3692         },{
3693             .name = "rerror",
3694             .type = QEMU_OPT_STRING,
3695             .help = "read error action",
3696         },{
3697             .name = "werror",
3698             .type = QEMU_OPT_STRING,
3699             .help = "write error action",
3700         },{
3701             .name = BDRV_OPT_READ_ONLY,
3702             .type = QEMU_OPT_BOOL,
3703             .help = "open drive file as read-only",
3704         },
3705 
3706         THROTTLE_OPTS,
3707 
3708         {
3709             .name = "throttling.group",
3710             .type = QEMU_OPT_STRING,
3711             .help = "name of the block throttling group",
3712         },{
3713             .name = "copy-on-read",
3714             .type = QEMU_OPT_BOOL,
3715             .help = "copy read data from backing file into image file",
3716         },{
3717             .name = "detect-zeroes",
3718             .type = QEMU_OPT_STRING,
3719             .help = "try to optimize zero writes (off, on, unmap)",
3720         },{
3721             .name = "stats-account-invalid",
3722             .type = QEMU_OPT_BOOL,
3723             .help = "whether to account for invalid I/O operations "
3724                     "in the statistics",
3725         },{
3726             .name = "stats-account-failed",
3727             .type = QEMU_OPT_BOOL,
3728             .help = "whether to account for failed I/O operations "
3729                     "in the statistics",
3730         },
3731         { /* end of list */ }
3732     },
3733 };
3734 
3735 QemuOptsList qemu_drive_opts = {
3736     .name = "drive",
3737     .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
3738     .desc = {
3739         /*
3740          * no elements => accept any params
3741          * validation will happen later
3742          */
3743         { /* end of list */ }
3744     },
3745 };
3746