xref: /openbmc/qemu/blockdev.c (revision 68ff2eeb299d562e437b49e9bb98f9d6f62fbf06)
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     bdrv_graph_rdlock_main_loop();
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         goto unlock;
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         goto unlock;
1440     }
1441 
1442     if (bdrv_op_is_blocked(state->old_bs,
1443                            BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
1444         goto unlock;
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             goto unlock;
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             goto unlock;
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             goto unlock;
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                 goto unlock;
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                 goto unlock;
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         goto unlock;
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         goto unlock;
1522     }
1523 
1524     if (state->new_bs->drv->is_filter) {
1525         error_setg(errp, "Filters cannot be used as overlays");
1526         goto unlock;
1527     }
1528 
1529     if (bdrv_cow_child(state->new_bs)) {
1530         error_setg(errp, "The overlay already has a backing image");
1531         goto unlock;
1532     }
1533 
1534     if (!state->new_bs->drv->supports_backing) {
1535         error_setg(errp, "The overlay does not support backing images");
1536         goto unlock;
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         bdrv_graph_rdunlock_main_loop();
1550         bdrv_drain_all_begin();
1551         bdrv_graph_rdlock_main_loop();
1552         ret = bdrv_inactivate(state->new_bs, errp);
1553         bdrv_drain_all_end();
1554         if (ret < 0) {
1555             goto unlock;
1556         }
1557     }
1558 
1559     ret = bdrv_append(state->new_bs, state->old_bs, errp);
1560     if (ret < 0) {
1561         goto unlock;
1562     }
1563     state->overlay_appended = true;
1564 unlock:
1565     bdrv_graph_rdunlock_main_loop();
1566 }
1567 
external_snapshot_commit(void * opaque)1568 static void external_snapshot_commit(void *opaque)
1569 {
1570     ExternalSnapshotState *state = opaque;
1571 
1572     /* We don't need (or want) to use the transactional
1573      * bdrv_reopen_multiple() across all the entries at once, because we
1574      * don't want to abort all of them if one of them fails the reopen */
1575     if (!qatomic_read(&state->old_bs->copy_on_read)) {
1576         bdrv_reopen_set_read_only(state->old_bs, true, NULL);
1577     }
1578 }
1579 
external_snapshot_abort(void * opaque)1580 static void external_snapshot_abort(void *opaque)
1581 {
1582     ExternalSnapshotState *state = opaque;
1583     if (state->new_bs) {
1584         if (state->overlay_appended) {
1585             AioContext *aio_context;
1586             AioContext *tmp_context;
1587             int ret;
1588 
1589             bdrv_graph_wrlock_drained();
1590 
1591             aio_context = bdrv_get_aio_context(state->old_bs);
1592 
1593             /*
1594              * Note that state->old_bs would not disappear during the
1595              * write-locked section, because the unref from
1596              * bdrv_set_backing_hd() only happens at the end of the write-locked
1597              * section. However, just be explicit about keeping a reference and
1598              * don't rely on that implicit detail.
1599              */
1600             bdrv_ref(state->old_bs);
1601             bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
1602 
1603             /*
1604              * The call to bdrv_set_backing_hd() above returns state->old_bs to
1605              * the main AioContext. As we're still going to be using it, return
1606              * it to the AioContext it was before.
1607              */
1608             tmp_context = bdrv_get_aio_context(state->old_bs);
1609             if (aio_context != tmp_context) {
1610                 ret = bdrv_try_change_aio_context_locked(state->old_bs,
1611                                                          aio_context, NULL,
1612                                                          NULL);
1613                 assert(ret == 0);
1614             }
1615 
1616             bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
1617             bdrv_graph_wrunlock();
1618 
1619             bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
1620         }
1621     }
1622 }
1623 
external_snapshot_clean(void * opaque)1624 static void external_snapshot_clean(void *opaque)
1625 {
1626     g_autofree ExternalSnapshotState *state = opaque;
1627 
1628     if (!state->old_bs) {
1629         return;
1630     }
1631 
1632     bdrv_drained_end(state->old_bs);
1633     bdrv_unref(state->new_bs);
1634 }
1635 
1636 typedef struct DriveBackupState {
1637     BlockDriverState *bs;
1638     BlockJob *job;
1639 } DriveBackupState;
1640 
1641 static BlockJob *do_backup_common(BackupCommon *backup,
1642                                   BlockDriverState *bs,
1643                                   BlockDriverState *target_bs,
1644                                   AioContext *aio_context,
1645                                   JobTxn *txn, Error **errp);
1646 
1647 static void drive_backup_commit(void *opaque);
1648 static void drive_backup_abort(void *opaque);
1649 static void drive_backup_clean(void *opaque);
1650 TransactionActionDrv drive_backup_drv = {
1651     .commit = drive_backup_commit,
1652     .abort = drive_backup_abort,
1653     .clean = drive_backup_clean,
1654 };
1655 
drive_backup_action(DriveBackup * backup,JobTxn * block_job_txn,Transaction * tran,Error ** errp)1656 static void drive_backup_action(DriveBackup *backup,
1657                                 JobTxn *block_job_txn,
1658                                 Transaction *tran, Error **errp)
1659 {
1660     DriveBackupState *state = g_new0(DriveBackupState, 1);
1661     BlockDriverState *bs;
1662     BlockDriverState *target_bs;
1663     BlockDriverState *source = NULL;
1664     AioContext *aio_context;
1665     const char *format;
1666     QDict *options;
1667     Error *local_err = NULL;
1668     int flags;
1669     int64_t size;
1670     bool set_backing_hd = false;
1671     int ret;
1672 
1673     GLOBAL_STATE_CODE();
1674 
1675     tran_add(tran, &drive_backup_drv, state);
1676 
1677     if (!backup->has_mode) {
1678         backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
1679     }
1680 
1681     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1682     if (!bs) {
1683         return;
1684     }
1685 
1686     if (!bs->drv) {
1687         error_setg(errp, "Device has no medium");
1688         return;
1689     }
1690 
1691     aio_context = bdrv_get_aio_context(bs);
1692 
1693     state->bs = bs;
1694     /* Paired with .clean() */
1695     bdrv_drained_begin(bs);
1696 
1697     format = backup->format;
1698     if (!format && backup->mode != NEW_IMAGE_MODE_EXISTING) {
1699         format = bs->drv->format_name;
1700     }
1701 
1702     /* Early check to avoid creating target */
1703     bdrv_graph_rdlock_main_loop();
1704     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
1705         bdrv_graph_rdunlock_main_loop();
1706         return;
1707     }
1708 
1709     flags = bs->open_flags | BDRV_O_RDWR;
1710 
1711     /*
1712      * See if we have a backing HD we can use to create our new image
1713      * on top of.
1714      */
1715     if (backup->sync == MIRROR_SYNC_MODE_TOP) {
1716         /*
1717          * Backup will not replace the source by the target, so none
1718          * of the filters skipped here will be removed (in contrast to
1719          * mirror).  Therefore, we can skip all of them when looking
1720          * for the first COW relationship.
1721          */
1722         source = bdrv_cow_bs(bdrv_skip_filters(bs));
1723         if (!source) {
1724             backup->sync = MIRROR_SYNC_MODE_FULL;
1725         }
1726     }
1727     if (backup->sync == MIRROR_SYNC_MODE_NONE) {
1728         source = bs;
1729         flags |= BDRV_O_NO_BACKING;
1730         set_backing_hd = true;
1731     }
1732     bdrv_graph_rdunlock_main_loop();
1733 
1734     size = bdrv_getlength(bs);
1735     if (size < 0) {
1736         error_setg_errno(errp, -size, "bdrv_getlength failed");
1737         return;
1738     }
1739 
1740     if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
1741         assert(format);
1742         if (source) {
1743             /* Implicit filters should not appear in the filename */
1744             BlockDriverState *explicit_backing;
1745 
1746             bdrv_graph_rdlock_main_loop();
1747             explicit_backing = bdrv_skip_implicit_filters(source);
1748             bdrv_refresh_filename(explicit_backing);
1749             bdrv_graph_rdunlock_main_loop();
1750 
1751             bdrv_img_create(backup->target, format,
1752                             explicit_backing->filename,
1753                             explicit_backing->drv->format_name, NULL,
1754                             size, flags, false, &local_err);
1755         } else {
1756             bdrv_img_create(backup->target, format, NULL, NULL, NULL,
1757                             size, flags, false, &local_err);
1758         }
1759     }
1760 
1761     if (local_err) {
1762         error_propagate(errp, local_err);
1763         return;
1764     }
1765 
1766     options = qdict_new();
1767     qdict_put_str(options, "discard", "unmap");
1768     qdict_put_str(options, "detect-zeroes", "unmap");
1769     if (format) {
1770         qdict_put_str(options, "driver", format);
1771     }
1772 
1773     target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
1774     if (!target_bs) {
1775         return;
1776     }
1777 
1778     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1779     if (ret < 0) {
1780         bdrv_unref(target_bs);
1781         return;
1782     }
1783 
1784     if (set_backing_hd) {
1785         bdrv_graph_wrlock_drained();
1786         ret = bdrv_set_backing_hd(target_bs, source, errp);
1787         bdrv_graph_wrunlock();
1788         if (ret < 0) {
1789             goto unref;
1790         }
1791     }
1792 
1793     state->job = do_backup_common(qapi_DriveBackup_base(backup),
1794                                   bs, target_bs, aio_context,
1795                                   block_job_txn, errp);
1796 
1797 unref:
1798     bdrv_unref(target_bs);
1799 }
1800 
drive_backup_commit(void * opaque)1801 static void drive_backup_commit(void *opaque)
1802 {
1803     DriveBackupState *state = opaque;
1804 
1805     assert(state->job);
1806     job_start(&state->job->job);
1807 }
1808 
drive_backup_abort(void * opaque)1809 static void drive_backup_abort(void *opaque)
1810 {
1811     DriveBackupState *state = opaque;
1812 
1813     if (state->job) {
1814         job_cancel_sync(&state->job->job, true);
1815     }
1816 }
1817 
drive_backup_clean(void * opaque)1818 static void drive_backup_clean(void *opaque)
1819 {
1820     g_autofree DriveBackupState *state = opaque;
1821 
1822     if (!state->bs) {
1823         return;
1824     }
1825 
1826     bdrv_drained_end(state->bs);
1827 }
1828 
1829 typedef struct BlockdevBackupState {
1830     BlockDriverState *bs;
1831     BlockJob *job;
1832 } BlockdevBackupState;
1833 
1834 static void blockdev_backup_commit(void *opaque);
1835 static void blockdev_backup_abort(void *opaque);
1836 static void blockdev_backup_clean(void *opaque);
1837 TransactionActionDrv blockdev_backup_drv = {
1838     .commit = blockdev_backup_commit,
1839     .abort = blockdev_backup_abort,
1840     .clean = blockdev_backup_clean,
1841 };
1842 
blockdev_backup_action(BlockdevBackup * backup,JobTxn * block_job_txn,Transaction * tran,Error ** errp)1843 static void blockdev_backup_action(BlockdevBackup *backup,
1844                                    JobTxn *block_job_txn,
1845                                    Transaction *tran, Error **errp)
1846 {
1847     BlockdevBackupState *state = g_new0(BlockdevBackupState, 1);
1848     BlockDriverState *bs;
1849     BlockDriverState *target_bs;
1850     AioContext *aio_context;
1851     int ret;
1852 
1853     tran_add(tran, &blockdev_backup_drv, state);
1854 
1855     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
1856     if (!bs) {
1857         return;
1858     }
1859 
1860     target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
1861     if (!target_bs) {
1862         return;
1863     }
1864 
1865     /* Honor bdrv_try_change_aio_context() context acquisition requirements. */
1866     aio_context = bdrv_get_aio_context(bs);
1867 
1868     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
1869     if (ret < 0) {
1870         return;
1871     }
1872 
1873     state->bs = bs;
1874 
1875     /* Paired with .clean() */
1876     bdrv_drained_begin(state->bs);
1877 
1878     state->job = do_backup_common(qapi_BlockdevBackup_base(backup),
1879                                   bs, target_bs, aio_context,
1880                                   block_job_txn, errp);
1881 }
1882 
blockdev_backup_commit(void * opaque)1883 static void blockdev_backup_commit(void *opaque)
1884 {
1885     BlockdevBackupState *state = opaque;
1886 
1887     assert(state->job);
1888     job_start(&state->job->job);
1889 }
1890 
blockdev_backup_abort(void * opaque)1891 static void blockdev_backup_abort(void *opaque)
1892 {
1893     BlockdevBackupState *state = opaque;
1894 
1895     if (state->job) {
1896         job_cancel_sync(&state->job->job, true);
1897     }
1898 }
1899 
blockdev_backup_clean(void * opaque)1900 static void blockdev_backup_clean(void *opaque)
1901 {
1902     g_autofree BlockdevBackupState *state = opaque;
1903 
1904     if (!state->bs) {
1905         return;
1906     }
1907 
1908     bdrv_drained_end(state->bs);
1909 }
1910 
1911 typedef struct BlockDirtyBitmapState {
1912     BdrvDirtyBitmap *bitmap;
1913     BlockDriverState *bs;
1914     HBitmap *backup;
1915     bool was_enabled;
1916 } BlockDirtyBitmapState;
1917 
1918 static void block_dirty_bitmap_add_abort(void *opaque);
1919 TransactionActionDrv block_dirty_bitmap_add_drv = {
1920     .abort = block_dirty_bitmap_add_abort,
1921     .clean = g_free,
1922 };
1923 
block_dirty_bitmap_add_action(BlockDirtyBitmapAdd * action,Transaction * tran,Error ** errp)1924 static void block_dirty_bitmap_add_action(BlockDirtyBitmapAdd *action,
1925                                           Transaction *tran, Error **errp)
1926 {
1927     Error *local_err = NULL;
1928     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1929 
1930     tran_add(tran, &block_dirty_bitmap_add_drv, state);
1931 
1932     /* AIO context taken and released within qmp_block_dirty_bitmap_add */
1933     qmp_block_dirty_bitmap_add(action->node, action->name,
1934                                action->has_granularity, action->granularity,
1935                                action->has_persistent, action->persistent,
1936                                action->has_disabled, action->disabled,
1937                                &local_err);
1938 
1939     if (!local_err) {
1940         state->bitmap = block_dirty_bitmap_lookup(action->node, action->name,
1941                                                   NULL, &error_abort);
1942     } else {
1943         error_propagate(errp, local_err);
1944     }
1945 }
1946 
block_dirty_bitmap_add_abort(void * opaque)1947 static void block_dirty_bitmap_add_abort(void *opaque)
1948 {
1949     BlockDirtyBitmapState *state = opaque;
1950 
1951     if (state->bitmap) {
1952         bdrv_release_dirty_bitmap(state->bitmap);
1953     }
1954 }
1955 
1956 static void block_dirty_bitmap_restore(void *opaque);
1957 static void block_dirty_bitmap_free_backup(void *opaque);
1958 TransactionActionDrv block_dirty_bitmap_clear_drv = {
1959     .abort = block_dirty_bitmap_restore,
1960     .commit = block_dirty_bitmap_free_backup,
1961     .clean = g_free,
1962 };
1963 
block_dirty_bitmap_clear_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)1964 static void block_dirty_bitmap_clear_action(BlockDirtyBitmap *action,
1965                                             Transaction *tran, Error **errp)
1966 {
1967     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
1968 
1969     tran_add(tran, &block_dirty_bitmap_clear_drv, state);
1970 
1971     state->bitmap = block_dirty_bitmap_lookup(action->node,
1972                                               action->name,
1973                                               &state->bs,
1974                                               errp);
1975     if (!state->bitmap) {
1976         return;
1977     }
1978 
1979     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_DEFAULT, errp)) {
1980         return;
1981     }
1982 
1983     bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
1984 }
1985 
block_dirty_bitmap_restore(void * opaque)1986 static void block_dirty_bitmap_restore(void *opaque)
1987 {
1988     BlockDirtyBitmapState *state = opaque;
1989 
1990     if (state->backup) {
1991         bdrv_restore_dirty_bitmap(state->bitmap, state->backup);
1992     }
1993 }
1994 
block_dirty_bitmap_free_backup(void * opaque)1995 static void block_dirty_bitmap_free_backup(void *opaque)
1996 {
1997     BlockDirtyBitmapState *state = opaque;
1998 
1999     hbitmap_free(state->backup);
2000 }
2001 
2002 static void block_dirty_bitmap_enable_abort(void *opaque);
2003 TransactionActionDrv block_dirty_bitmap_enable_drv = {
2004     .abort = block_dirty_bitmap_enable_abort,
2005     .clean = g_free,
2006 };
2007 
block_dirty_bitmap_enable_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)2008 static void block_dirty_bitmap_enable_action(BlockDirtyBitmap *action,
2009                                              Transaction *tran, Error **errp)
2010 {
2011     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2012 
2013     tran_add(tran, &block_dirty_bitmap_enable_drv, state);
2014 
2015     state->bitmap = block_dirty_bitmap_lookup(action->node,
2016                                               action->name,
2017                                               NULL,
2018                                               errp);
2019     if (!state->bitmap) {
2020         return;
2021     }
2022 
2023     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2024         return;
2025     }
2026 
2027     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2028     bdrv_enable_dirty_bitmap(state->bitmap);
2029 }
2030 
block_dirty_bitmap_enable_abort(void * opaque)2031 static void block_dirty_bitmap_enable_abort(void *opaque)
2032 {
2033     BlockDirtyBitmapState *state = opaque;
2034 
2035     if (!state->was_enabled) {
2036         bdrv_disable_dirty_bitmap(state->bitmap);
2037     }
2038 }
2039 
2040 static void block_dirty_bitmap_disable_abort(void *opaque);
2041 TransactionActionDrv block_dirty_bitmap_disable_drv = {
2042     .abort = block_dirty_bitmap_disable_abort,
2043     .clean = g_free,
2044 };
2045 
block_dirty_bitmap_disable_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)2046 static void block_dirty_bitmap_disable_action(BlockDirtyBitmap *action,
2047                                               Transaction *tran, Error **errp)
2048 {
2049     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2050 
2051     tran_add(tran, &block_dirty_bitmap_disable_drv, state);
2052 
2053     state->bitmap = block_dirty_bitmap_lookup(action->node,
2054                                               action->name,
2055                                               NULL,
2056                                               errp);
2057     if (!state->bitmap) {
2058         return;
2059     }
2060 
2061     if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2062         return;
2063     }
2064 
2065     state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
2066     bdrv_disable_dirty_bitmap(state->bitmap);
2067 }
2068 
block_dirty_bitmap_disable_abort(void * opaque)2069 static void block_dirty_bitmap_disable_abort(void *opaque)
2070 {
2071     BlockDirtyBitmapState *state = opaque;
2072 
2073     if (state->was_enabled) {
2074         bdrv_enable_dirty_bitmap(state->bitmap);
2075     }
2076 }
2077 
2078 TransactionActionDrv block_dirty_bitmap_merge_drv = {
2079     .commit = block_dirty_bitmap_free_backup,
2080     .abort = block_dirty_bitmap_restore,
2081     .clean = g_free,
2082 };
2083 
block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge * action,Transaction * tran,Error ** errp)2084 static void block_dirty_bitmap_merge_action(BlockDirtyBitmapMerge *action,
2085                                             Transaction *tran, Error **errp)
2086 {
2087     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2088 
2089     tran_add(tran, &block_dirty_bitmap_merge_drv, state);
2090 
2091     state->bitmap = block_dirty_bitmap_merge(action->node, action->target,
2092                                              action->bitmaps, &state->backup,
2093                                              errp);
2094 }
2095 
2096 static void block_dirty_bitmap_remove_commit(void *opaque);
2097 static void block_dirty_bitmap_remove_abort(void *opaque);
2098 TransactionActionDrv block_dirty_bitmap_remove_drv = {
2099     .commit = block_dirty_bitmap_remove_commit,
2100     .abort = block_dirty_bitmap_remove_abort,
2101     .clean = g_free,
2102 };
2103 
block_dirty_bitmap_remove_action(BlockDirtyBitmap * action,Transaction * tran,Error ** errp)2104 static void block_dirty_bitmap_remove_action(BlockDirtyBitmap *action,
2105                                              Transaction *tran, Error **errp)
2106 {
2107     BlockDirtyBitmapState *state = g_new0(BlockDirtyBitmapState, 1);
2108 
2109     tran_add(tran, &block_dirty_bitmap_remove_drv, state);
2110 
2111 
2112     state->bitmap = block_dirty_bitmap_remove(action->node, action->name,
2113                                               false, &state->bs, errp);
2114     if (state->bitmap) {
2115         bdrv_dirty_bitmap_skip_store(state->bitmap, true);
2116         bdrv_dirty_bitmap_set_busy(state->bitmap, true);
2117     }
2118 }
2119 
block_dirty_bitmap_remove_abort(void * opaque)2120 static void block_dirty_bitmap_remove_abort(void *opaque)
2121 {
2122     BlockDirtyBitmapState *state = opaque;
2123 
2124     if (state->bitmap) {
2125         bdrv_dirty_bitmap_skip_store(state->bitmap, false);
2126         bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2127     }
2128 }
2129 
block_dirty_bitmap_remove_commit(void * opaque)2130 static void block_dirty_bitmap_remove_commit(void *opaque)
2131 {
2132     BlockDirtyBitmapState *state = opaque;
2133 
2134     bdrv_dirty_bitmap_set_busy(state->bitmap, false);
2135     bdrv_release_dirty_bitmap(state->bitmap);
2136 }
2137 
2138 static void abort_commit(void *opaque);
2139 TransactionActionDrv abort_drv = {
2140     .commit = abort_commit,
2141 };
2142 
abort_action(Transaction * tran,Error ** errp)2143 static void abort_action(Transaction *tran, Error **errp)
2144 {
2145     tran_add(tran, &abort_drv, NULL);
2146     error_setg(errp, "Transaction aborted using Abort action");
2147 }
2148 
abort_commit(void * opaque)2149 static void abort_commit(void *opaque)
2150 {
2151     g_assert_not_reached(); /* this action never succeeds */
2152 }
2153 
transaction_action(TransactionAction * act,JobTxn * block_job_txn,Transaction * tran,Error ** errp)2154 static void transaction_action(TransactionAction *act, JobTxn *block_job_txn,
2155                                Transaction *tran, Error **errp)
2156 {
2157     switch (act->type) {
2158     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
2159     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
2160         external_snapshot_action(act, tran, errp);
2161         return;
2162     case TRANSACTION_ACTION_KIND_DRIVE_BACKUP:
2163         drive_backup_action(act->u.drive_backup.data,
2164                             block_job_txn, tran, errp);
2165         return;
2166     case TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP:
2167         blockdev_backup_action(act->u.blockdev_backup.data,
2168                                block_job_txn, tran, errp);
2169         return;
2170     case TRANSACTION_ACTION_KIND_ABORT:
2171         abort_action(tran, errp);
2172         return;
2173     case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC:
2174         internal_snapshot_action(act->u.blockdev_snapshot_internal_sync.data,
2175                                  tran, errp);
2176         return;
2177     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD:
2178         block_dirty_bitmap_add_action(act->u.block_dirty_bitmap_add.data,
2179                                       tran, errp);
2180         return;
2181     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR:
2182         block_dirty_bitmap_clear_action(act->u.block_dirty_bitmap_clear.data,
2183                                         tran, errp);
2184         return;
2185     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ENABLE:
2186         block_dirty_bitmap_enable_action(act->u.block_dirty_bitmap_enable.data,
2187                                          tran, errp);
2188         return;
2189     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_DISABLE:
2190         block_dirty_bitmap_disable_action(
2191                 act->u.block_dirty_bitmap_disable.data, tran, errp);
2192         return;
2193     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_MERGE:
2194         block_dirty_bitmap_merge_action(act->u.block_dirty_bitmap_merge.data,
2195                                         tran, errp);
2196         return;
2197     case TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_REMOVE:
2198         block_dirty_bitmap_remove_action(act->u.block_dirty_bitmap_remove.data,
2199                                          tran, errp);
2200         return;
2201     /*
2202      * Where are transactions for MIRROR, COMMIT and STREAM?
2203      * Although these blockjobs use transaction callbacks like the backup job,
2204      * these jobs do not necessarily adhere to transaction semantics.
2205      * These jobs may not fully undo all of their actions on abort, nor do they
2206      * necessarily work in transactions with more than one job in them.
2207      */
2208     case TRANSACTION_ACTION_KIND__MAX:
2209     default:
2210         g_assert_not_reached();
2211     };
2212 }
2213 
2214 
2215 /*
2216  * 'Atomic' group operations.  The operations are performed as a set, and if
2217  * any fail then we roll back all operations in the group.
2218  *
2219  * Always run under BQL.
2220  */
qmp_transaction(TransactionActionList * actions,struct TransactionProperties * properties,Error ** errp)2221 void qmp_transaction(TransactionActionList *actions,
2222                      struct TransactionProperties *properties,
2223                      Error **errp)
2224 {
2225     TransactionActionList *act;
2226     JobTxn *block_job_txn = NULL;
2227     Error *local_err = NULL;
2228     Transaction *tran;
2229     ActionCompletionMode comp_mode =
2230         properties ? properties->completion_mode :
2231         ACTION_COMPLETION_MODE_INDIVIDUAL;
2232 
2233     GLOBAL_STATE_CODE();
2234 
2235     /* Does this transaction get canceled as a group on failure?
2236      * If not, we don't really need to make a JobTxn.
2237      */
2238     if (comp_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
2239         for (act = actions; act; act = act->next) {
2240             TransactionActionKind type = act->value->type;
2241 
2242             if (type != TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP &&
2243                 type != TRANSACTION_ACTION_KIND_DRIVE_BACKUP)
2244             {
2245                 error_setg(errp,
2246                            "Action '%s' does not support transaction property "
2247                            "completion-mode = %s",
2248                            TransactionActionKind_str(type),
2249                            ActionCompletionMode_str(comp_mode));
2250                 return;
2251             }
2252         }
2253 
2254         block_job_txn = job_txn_new();
2255     }
2256 
2257     /* drain all i/o before any operations */
2258     bdrv_drain_all();
2259 
2260     tran = tran_new();
2261 
2262     /* We don't do anything in this loop that commits us to the operations */
2263     for (act = actions; act; act = act->next) {
2264         transaction_action(act->value, block_job_txn, tran, &local_err);
2265         if (local_err) {
2266             error_propagate(errp, local_err);
2267             goto delete_and_fail;
2268         }
2269     }
2270 
2271     tran_commit(tran);
2272 
2273     /* success */
2274     goto exit;
2275 
2276 delete_and_fail:
2277     /* failure, and it is all-or-none; roll back all operations */
2278     tran_abort(tran);
2279 exit:
2280     job_txn_unref(block_job_txn);
2281 }
2282 
qmp_x_debug_block_dirty_bitmap_sha256(const char * node,const char * name,Error ** errp)2283 BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
2284                                                               const char *name,
2285                                                               Error **errp)
2286 {
2287     BdrvDirtyBitmap *bitmap;
2288     BlockDriverState *bs;
2289     BlockDirtyBitmapSha256 *ret = NULL;
2290     char *sha256;
2291 
2292     bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
2293     if (!bitmap || !bs) {
2294         return NULL;
2295     }
2296 
2297     sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
2298     if (sha256 == NULL) {
2299         return NULL;
2300     }
2301 
2302     ret = g_new(BlockDirtyBitmapSha256, 1);
2303     ret->sha256 = sha256;
2304 
2305     return ret;
2306 }
2307 
qmp_block_resize(const char * device,const char * node_name,int64_t size,Error ** errp)2308 void coroutine_fn qmp_block_resize(const char *device, const char *node_name,
2309                                    int64_t size, Error **errp)
2310 {
2311     Error *local_err = NULL;
2312     BlockBackend *blk;
2313     BlockDriverState *bs;
2314     AioContext *old_ctx;
2315 
2316     bs = bdrv_lookup_bs(device, node_name, &local_err);
2317     if (local_err) {
2318         error_propagate(errp, local_err);
2319         return;
2320     }
2321 
2322     if (size < 0) {
2323         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
2324         return;
2325     }
2326 
2327     bdrv_graph_co_rdlock();
2328     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, errp)) {
2329         bdrv_graph_co_rdunlock();
2330         return;
2331     }
2332     bdrv_graph_co_rdunlock();
2333 
2334     blk = blk_co_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
2335     if (!blk) {
2336         return;
2337     }
2338 
2339     bdrv_drained_begin(bs);
2340 
2341     old_ctx = bdrv_co_enter(bs);
2342     blk_co_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
2343     bdrv_co_leave(bs, old_ctx);
2344 
2345     bdrv_drained_end(bs);
2346     blk_co_unref(blk);
2347 }
2348 
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)2349 void qmp_block_stream(const char *job_id, const char *device,
2350                       const char *base,
2351                       const char *base_node,
2352                       const char *backing_file,
2353                       bool has_backing_mask_protocol,
2354                       bool backing_mask_protocol,
2355                       const char *bottom,
2356                       bool has_speed, int64_t speed,
2357                       bool has_on_error, BlockdevOnError on_error,
2358                       const char *filter_node_name,
2359                       bool has_auto_finalize, bool auto_finalize,
2360                       bool has_auto_dismiss, bool auto_dismiss,
2361                       Error **errp)
2362 {
2363     BlockDriverState *bs, *iter, *iter_end;
2364     BlockDriverState *base_bs = NULL;
2365     BlockDriverState *bottom_bs = NULL;
2366     AioContext *aio_context;
2367     Error *local_err = NULL;
2368     int job_flags = JOB_DEFAULT;
2369 
2370     GLOBAL_STATE_CODE();
2371 
2372     if (base && base_node) {
2373         error_setg(errp, "'base' and 'base-node' cannot be specified "
2374                    "at the same time");
2375         return;
2376     }
2377 
2378     if (base && bottom) {
2379         error_setg(errp, "'base' and 'bottom' cannot be specified "
2380                    "at the same time");
2381         return;
2382     }
2383 
2384     if (bottom && base_node) {
2385         error_setg(errp, "'bottom' and 'base-node' cannot be specified "
2386                    "at the same time");
2387         return;
2388     }
2389 
2390     if (!has_backing_mask_protocol) {
2391         backing_mask_protocol = false;
2392     }
2393 
2394     if (!has_on_error) {
2395         on_error = BLOCKDEV_ON_ERROR_REPORT;
2396     }
2397 
2398     bs = bdrv_lookup_bs(device, device, errp);
2399     if (!bs) {
2400         return;
2401     }
2402 
2403     aio_context = bdrv_get_aio_context(bs);
2404 
2405     bdrv_graph_rdlock_main_loop();
2406     if (base) {
2407         base_bs = bdrv_find_backing_image(bs, base);
2408         if (base_bs == NULL) {
2409             error_setg(errp, "Can't find '%s' in the backing chain", base);
2410             goto out_rdlock;
2411         }
2412         assert(bdrv_get_aio_context(base_bs) == aio_context);
2413     }
2414 
2415     if (base_node) {
2416         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2417         if (!base_bs) {
2418             goto out_rdlock;
2419         }
2420         if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
2421             error_setg(errp, "Node '%s' is not a backing image of '%s'",
2422                        base_node, device);
2423             goto out_rdlock;
2424         }
2425         assert(bdrv_get_aio_context(base_bs) == aio_context);
2426 
2427         bdrv_refresh_filename(base_bs);
2428     }
2429 
2430     if (bottom) {
2431         bottom_bs = bdrv_lookup_bs(NULL, bottom, errp);
2432         if (!bottom_bs) {
2433             goto out_rdlock;
2434         }
2435         if (!bottom_bs->drv) {
2436             error_setg(errp, "Node '%s' is not open", bottom);
2437             goto out_rdlock;
2438         }
2439         if (bottom_bs->drv->is_filter) {
2440             error_setg(errp, "Node '%s' is a filter, use a non-filter node "
2441                        "as 'bottom'", bottom);
2442             goto out_rdlock;
2443         }
2444         if (!bdrv_chain_contains(bs, bottom_bs)) {
2445             error_setg(errp, "Node '%s' is not in a chain starting from '%s'",
2446                        bottom, device);
2447             goto out_rdlock;
2448         }
2449         assert(bdrv_get_aio_context(bottom_bs) == aio_context);
2450     }
2451 
2452     /*
2453      * Check for op blockers in the whole chain between bs and base (or bottom)
2454      */
2455     iter_end = bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
2456     for (iter = bs; iter && iter != iter_end;
2457          iter = bdrv_filter_or_cow_bs(iter))
2458     {
2459         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
2460             goto out_rdlock;
2461         }
2462     }
2463     bdrv_graph_rdunlock_main_loop();
2464 
2465     /* if we are streaming the entire chain, the result will have no backing
2466      * file, and specifying one is therefore an error */
2467     if (!base_bs && backing_file) {
2468         error_setg(errp, "backing file specified, but streaming the "
2469                          "entire chain");
2470         return;
2471     }
2472 
2473     if (has_auto_finalize && !auto_finalize) {
2474         job_flags |= JOB_MANUAL_FINALIZE;
2475     }
2476     if (has_auto_dismiss && !auto_dismiss) {
2477         job_flags |= JOB_MANUAL_DISMISS;
2478     }
2479 
2480     stream_start(job_id, bs, base_bs, backing_file,
2481                  backing_mask_protocol,
2482                  bottom_bs, job_flags, has_speed ? speed : 0, on_error,
2483                  filter_node_name, &local_err);
2484     if (local_err) {
2485         error_propagate(errp, local_err);
2486         return;
2487     }
2488 
2489     trace_qmp_block_stream(bs);
2490     return;
2491 
2492 out_rdlock:
2493     bdrv_graph_rdunlock_main_loop();
2494 }
2495 
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)2496 void qmp_block_commit(const char *job_id, const char *device,
2497                       const char *base_node,
2498                       const char *base,
2499                       const char *top_node,
2500                       const char *top,
2501                       const char *backing_file,
2502                       bool has_backing_mask_protocol,
2503                       bool backing_mask_protocol,
2504                       bool has_speed, int64_t speed,
2505                       bool has_on_error, BlockdevOnError on_error,
2506                       const char *filter_node_name,
2507                       bool has_auto_finalize, bool auto_finalize,
2508                       bool has_auto_dismiss, bool auto_dismiss,
2509                       Error **errp)
2510 {
2511     BlockDriverState *bs;
2512     BlockDriverState *iter;
2513     BlockDriverState *base_bs, *top_bs;
2514     AioContext *aio_context;
2515     Error *local_err = NULL;
2516     int job_flags = JOB_DEFAULT;
2517     uint64_t top_perm, top_shared;
2518 
2519     /* TODO We'll eventually have to take a writer lock in this function */
2520     GRAPH_RDLOCK_GUARD_MAINLOOP();
2521 
2522     if (!has_speed) {
2523         speed = 0;
2524     }
2525     if (!has_on_error) {
2526         on_error = BLOCKDEV_ON_ERROR_REPORT;
2527     }
2528     if (has_auto_finalize && !auto_finalize) {
2529         job_flags |= JOB_MANUAL_FINALIZE;
2530     }
2531     if (has_auto_dismiss && !auto_dismiss) {
2532         job_flags |= JOB_MANUAL_DISMISS;
2533     }
2534     if (!has_backing_mask_protocol) {
2535         backing_mask_protocol = false;
2536     }
2537 
2538     /* Important Note:
2539      *  libvirt relies on the DeviceNotFound error class in order to probe for
2540      *  live commit feature versions; for this to work, we must make sure to
2541      *  perform the device lookup before any generic errors that may occur in a
2542      *  scenario in which all optional arguments are omitted. */
2543     bs = qmp_get_root_bs(device, &local_err);
2544     if (!bs) {
2545         bs = bdrv_lookup_bs(device, device, NULL);
2546         if (!bs) {
2547             error_free(local_err);
2548             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
2549                       "Device '%s' not found", device);
2550         } else {
2551             error_propagate(errp, local_err);
2552         }
2553         return;
2554     }
2555 
2556     aio_context = bdrv_get_aio_context(bs);
2557 
2558     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
2559         return;
2560     }
2561 
2562     /* default top_bs is the active layer */
2563     top_bs = bs;
2564 
2565     if (top_node && top) {
2566         error_setg(errp, "'top-node' and 'top' are mutually exclusive");
2567         return;
2568     } else if (top_node) {
2569         top_bs = bdrv_lookup_bs(NULL, top_node, errp);
2570         if (top_bs == NULL) {
2571             return;
2572         }
2573         if (!bdrv_chain_contains(bs, top_bs)) {
2574             error_setg(errp, "'%s' is not in this backing file chain",
2575                        top_node);
2576             return;
2577         }
2578     } else if (top) {
2579         /* This strcmp() is just a shortcut, there is no need to
2580          * refresh @bs's filename.  If it mismatches,
2581          * bdrv_find_backing_image() will do the refresh and may still
2582          * return @bs. */
2583         if (strcmp(bs->filename, top) != 0) {
2584             top_bs = bdrv_find_backing_image(bs, top);
2585         }
2586     }
2587 
2588     if (top_bs == NULL) {
2589         error_setg(errp, "Top image file %s not found", top ? top : "NULL");
2590         return;
2591     }
2592 
2593     assert(bdrv_get_aio_context(top_bs) == aio_context);
2594 
2595     if (base_node && base) {
2596         error_setg(errp, "'base-node' and 'base' are mutually exclusive");
2597         return;
2598     } else if (base_node) {
2599         base_bs = bdrv_lookup_bs(NULL, base_node, errp);
2600         if (base_bs == NULL) {
2601             return;
2602         }
2603         if (!bdrv_chain_contains(top_bs, base_bs)) {
2604             error_setg(errp, "'%s' is not in this backing file chain",
2605                        base_node);
2606             return;
2607         }
2608     } else if (base) {
2609         base_bs = bdrv_find_backing_image(top_bs, base);
2610         if (base_bs == NULL) {
2611             error_setg(errp, "Can't find '%s' in the backing chain", base);
2612             return;
2613         }
2614     } else {
2615         base_bs = bdrv_find_base(top_bs);
2616         if (base_bs == NULL) {
2617             error_setg(errp, "There is no backimg image");
2618             return;
2619         }
2620     }
2621 
2622     assert(bdrv_get_aio_context(base_bs) == aio_context);
2623 
2624     for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
2625          iter = bdrv_filter_or_cow_bs(iter))
2626     {
2627         if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2628             return;
2629         }
2630     }
2631 
2632     /* Do not allow attempts to commit an image into itself */
2633     if (top_bs == base_bs) {
2634         error_setg(errp, "cannot commit an image into itself");
2635         return;
2636     }
2637 
2638     /*
2639      * Active commit is required if and only if someone has taken a
2640      * WRITE permission on the top node.  Historically, we have always
2641      * used active commit for top nodes, so continue that practice
2642      * lest we possibly break clients that rely on this behavior, e.g.
2643      * to later attach this node to a writing parent.
2644      * (Active commit is never really wrong.)
2645      */
2646     bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared);
2647     if (top_perm & BLK_PERM_WRITE ||
2648         bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs))
2649     {
2650         if (backing_file) {
2651             if (bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs)) {
2652                 error_setg(errp, "'backing-file' specified,"
2653                                  " but 'top' is the active layer");
2654             } else {
2655                 error_setg(errp, "'backing-file' specified, but 'top' has a "
2656                                  "writer on it");
2657             }
2658             return;
2659         }
2660         if (!job_id) {
2661             /*
2662              * Emulate here what block_job_create() does, because it
2663              * is possible that @bs != @top_bs (the block job should
2664              * be named after @bs, even if @top_bs is the actual
2665              * source)
2666              */
2667             job_id = bdrv_get_device_name(bs);
2668         }
2669         commit_active_start(job_id, top_bs, base_bs, job_flags, speed, on_error,
2670                             filter_node_name, NULL, NULL, false, &local_err);
2671     } else {
2672         BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
2673         if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
2674             return;
2675         }
2676         commit_start(job_id, bs, base_bs, top_bs, job_flags,
2677                      speed, on_error, backing_file,
2678                      backing_mask_protocol,
2679                      filter_node_name, &local_err);
2680     }
2681     if (local_err != NULL) {
2682         error_propagate(errp, local_err);
2683         return;
2684     }
2685 }
2686 
2687 /* 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)2688 static BlockJob *do_backup_common(BackupCommon *backup,
2689                                   BlockDriverState *bs,
2690                                   BlockDriverState *target_bs,
2691                                   AioContext *aio_context,
2692                                   JobTxn *txn, Error **errp)
2693 {
2694     BlockJob *job = NULL;
2695     BdrvDirtyBitmap *bmap = NULL;
2696     BackupPerf perf = { .max_workers = 64 };
2697     int job_flags = JOB_DEFAULT;
2698     OnCbwError on_cbw_error = ON_CBW_ERROR_BREAK_GUEST_WRITE;
2699 
2700     if (!backup->has_speed) {
2701         backup->speed = 0;
2702     }
2703     if (!backup->has_on_source_error) {
2704         backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2705     }
2706     if (!backup->has_on_target_error) {
2707         backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2708     }
2709     if (!backup->has_auto_finalize) {
2710         backup->auto_finalize = true;
2711     }
2712     if (!backup->has_auto_dismiss) {
2713         backup->auto_dismiss = true;
2714     }
2715     if (!backup->has_compress) {
2716         backup->compress = false;
2717     }
2718 
2719     if (backup->x_perf) {
2720         if (backup->x_perf->has_use_copy_range) {
2721             perf.use_copy_range = backup->x_perf->use_copy_range;
2722         }
2723         if (backup->x_perf->has_max_workers) {
2724             perf.max_workers = backup->x_perf->max_workers;
2725         }
2726         if (backup->x_perf->has_max_chunk) {
2727             perf.max_chunk = backup->x_perf->max_chunk;
2728         }
2729         if (backup->x_perf->has_min_cluster_size) {
2730             perf.min_cluster_size = backup->x_perf->min_cluster_size;
2731         }
2732     }
2733 
2734     if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) ||
2735         (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL)) {
2736         /* done before desugaring 'incremental' to print the right message */
2737         if (!backup->bitmap) {
2738             error_setg(errp, "must provide a valid bitmap name for "
2739                        "'%s' sync mode", MirrorSyncMode_str(backup->sync));
2740             return NULL;
2741         }
2742     }
2743 
2744     if (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL) {
2745         if (backup->has_bitmap_mode &&
2746             backup->bitmap_mode != BITMAP_SYNC_MODE_ON_SUCCESS) {
2747             error_setg(errp, "Bitmap sync mode must be '%s' "
2748                        "when using sync mode '%s'",
2749                        BitmapSyncMode_str(BITMAP_SYNC_MODE_ON_SUCCESS),
2750                        MirrorSyncMode_str(backup->sync));
2751             return NULL;
2752         }
2753         backup->has_bitmap_mode = true;
2754         backup->sync = MIRROR_SYNC_MODE_BITMAP;
2755         backup->bitmap_mode = BITMAP_SYNC_MODE_ON_SUCCESS;
2756     }
2757 
2758     if (backup->bitmap) {
2759         bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
2760         if (!bmap) {
2761             error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
2762             return NULL;
2763         }
2764         if (!backup->has_bitmap_mode) {
2765             error_setg(errp, "Bitmap sync mode must be given "
2766                        "when providing a bitmap");
2767             return NULL;
2768         }
2769         if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_ALLOW_RO, errp)) {
2770             return NULL;
2771         }
2772 
2773         /* This does not produce a useful bitmap artifact: */
2774         if (backup->sync == MIRROR_SYNC_MODE_NONE) {
2775             error_setg(errp, "sync mode '%s' does not produce meaningful bitmap"
2776                        " outputs", MirrorSyncMode_str(backup->sync));
2777             return NULL;
2778         }
2779 
2780         /* If the bitmap isn't used for input or output, this is useless: */
2781         if (backup->bitmap_mode == BITMAP_SYNC_MODE_NEVER &&
2782             backup->sync != MIRROR_SYNC_MODE_BITMAP) {
2783             error_setg(errp, "Bitmap sync mode '%s' has no meaningful effect"
2784                        " when combined with sync mode '%s'",
2785                        BitmapSyncMode_str(backup->bitmap_mode),
2786                        MirrorSyncMode_str(backup->sync));
2787             return NULL;
2788         }
2789     }
2790 
2791     if (!backup->bitmap && backup->has_bitmap_mode) {
2792         error_setg(errp, "Cannot specify bitmap sync mode without a bitmap");
2793         return NULL;
2794     }
2795 
2796     if (!backup->auto_finalize) {
2797         job_flags |= JOB_MANUAL_FINALIZE;
2798     }
2799     if (!backup->auto_dismiss) {
2800         job_flags |= JOB_MANUAL_DISMISS;
2801     }
2802 
2803     if (backup->has_on_cbw_error) {
2804         on_cbw_error = backup->on_cbw_error;
2805     }
2806 
2807     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
2808                             backup->sync, bmap, backup->bitmap_mode,
2809                             backup->compress, backup->discard_source,
2810                             backup->filter_node_name,
2811                             &perf,
2812                             backup->on_source_error,
2813                             backup->on_target_error,
2814                             on_cbw_error,
2815                             job_flags, NULL, NULL, txn, errp);
2816     return job;
2817 }
2818 
qmp_drive_backup(DriveBackup * backup,Error ** errp)2819 void qmp_drive_backup(DriveBackup *backup, Error **errp)
2820 {
2821     TransactionAction action = {
2822         .type = TRANSACTION_ACTION_KIND_DRIVE_BACKUP,
2823         .u.drive_backup.data = backup,
2824     };
2825     blockdev_do_action(&action, errp);
2826 }
2827 
qmp_query_named_block_nodes(bool has_flat,bool flat,Error ** errp)2828 BlockDeviceInfoList *qmp_query_named_block_nodes(bool has_flat,
2829                                                  bool flat,
2830                                                  Error **errp)
2831 {
2832     bool return_flat = has_flat && flat;
2833 
2834     return bdrv_named_nodes_list(return_flat, errp);
2835 }
2836 
qmp_x_debug_query_block_graph(Error ** errp)2837 XDbgBlockGraph *qmp_x_debug_query_block_graph(Error **errp)
2838 {
2839     GRAPH_RDLOCK_GUARD_MAINLOOP();
2840 
2841     return bdrv_get_xdbg_block_graph(errp);
2842 }
2843 
qmp_blockdev_backup(BlockdevBackup * backup,Error ** errp)2844 void qmp_blockdev_backup(BlockdevBackup *backup, Error **errp)
2845 {
2846     TransactionAction action = {
2847         .type = TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP,
2848         .u.blockdev_backup.data = backup,
2849     };
2850     blockdev_do_action(&action, errp);
2851 }
2852 
2853 /* Parameter check and block job starting for drive mirroring.
2854  * Caller should hold @device and @target's aio context (must be the same).
2855  **/
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)2856 static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
2857                                    BlockDriverState *target,
2858                                    const char *replaces,
2859                                    enum MirrorSyncMode sync,
2860                                    BlockMirrorBackingMode backing_mode,
2861                                    bool target_is_zero,
2862                                    bool has_speed, int64_t speed,
2863                                    bool has_granularity, uint32_t granularity,
2864                                    bool has_buf_size, int64_t buf_size,
2865                                    bool has_on_source_error,
2866                                    BlockdevOnError on_source_error,
2867                                    bool has_on_target_error,
2868                                    BlockdevOnError on_target_error,
2869                                    bool has_unmap, bool unmap,
2870                                    const char *filter_node_name,
2871                                    bool has_copy_mode, MirrorCopyMode copy_mode,
2872                                    bool has_auto_finalize, bool auto_finalize,
2873                                    bool has_auto_dismiss, bool auto_dismiss,
2874                                    Error **errp)
2875 {
2876     BlockDriverState *unfiltered_bs;
2877     int job_flags = JOB_DEFAULT;
2878 
2879     GLOBAL_STATE_CODE();
2880     GRAPH_RDLOCK_GUARD_MAINLOOP();
2881 
2882     if (!has_speed) {
2883         speed = 0;
2884     }
2885     if (!has_on_source_error) {
2886         on_source_error = BLOCKDEV_ON_ERROR_REPORT;
2887     }
2888     if (!has_on_target_error) {
2889         on_target_error = BLOCKDEV_ON_ERROR_REPORT;
2890     }
2891     if (!has_granularity) {
2892         granularity = 0;
2893     }
2894     if (!has_buf_size) {
2895         buf_size = 0;
2896     }
2897     if (!has_unmap) {
2898         unmap = true;
2899     }
2900     if (!has_copy_mode) {
2901         copy_mode = MIRROR_COPY_MODE_BACKGROUND;
2902     }
2903     if (has_auto_finalize && !auto_finalize) {
2904         job_flags |= JOB_MANUAL_FINALIZE;
2905     }
2906     if (has_auto_dismiss && !auto_dismiss) {
2907         job_flags |= JOB_MANUAL_DISMISS;
2908     }
2909 
2910     if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
2911         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2912                    "a value in range [512B, 64MB]");
2913         return;
2914     }
2915     if (granularity & (granularity - 1)) {
2916         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
2917                    "a power of 2");
2918         return;
2919     }
2920 
2921     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2922         return;
2923     }
2924     if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
2925         return;
2926     }
2927 
2928     if (!replaces) {
2929         /* We want to mirror from @bs, but keep implicit filters on top */
2930         unfiltered_bs = bdrv_skip_implicit_filters(bs);
2931         if (unfiltered_bs != bs) {
2932             replaces = unfiltered_bs->node_name;
2933         }
2934     }
2935 
2936     if (replaces) {
2937         BlockDriverState *to_replace_bs;
2938         int64_t bs_size, replace_size;
2939 
2940         bs_size = bdrv_getlength(bs);
2941         if (bs_size < 0) {
2942             error_setg_errno(errp, -bs_size, "Failed to query device's size");
2943             return;
2944         }
2945 
2946         to_replace_bs = check_to_replace_node(bs, replaces, errp);
2947         if (!to_replace_bs) {
2948             return;
2949         }
2950 
2951         replace_size = bdrv_getlength(to_replace_bs);
2952 
2953         if (replace_size < 0) {
2954             error_setg_errno(errp, -replace_size,
2955                              "Failed to query the replacement node's size");
2956             return;
2957         }
2958         if (bs_size != replace_size) {
2959             error_setg(errp, "cannot replace image with a mirror image of "
2960                              "different size");
2961             return;
2962         }
2963     }
2964 
2965     /* pass the node name to replace to mirror start since it's loose coupling
2966      * and will allow to check whether the node still exist at mirror completion
2967      */
2968     mirror_start(job_id, bs, target, replaces, job_flags,
2969                  speed, granularity, buf_size, sync, backing_mode,
2970                  target_is_zero, on_source_error, on_target_error, unmap,
2971                  filter_node_name, copy_mode, errp);
2972 }
2973 
qmp_drive_mirror(DriveMirror * arg,Error ** errp)2974 void qmp_drive_mirror(DriveMirror *arg, Error **errp)
2975 {
2976     BlockDriverState *bs;
2977     BlockDriverState *target_backing_bs, *target_bs;
2978     AioContext *aio_context;
2979     BlockMirrorBackingMode backing_mode;
2980     Error *local_err = NULL;
2981     QDict *options = NULL;
2982     int flags;
2983     int64_t size;
2984     const char *format = arg->format;
2985     bool target_is_zero;
2986     int ret;
2987 
2988     bs = qmp_get_root_bs(arg->device, errp);
2989     if (!bs) {
2990         return;
2991     }
2992 
2993     /* Early check to avoid creating target */
2994     bdrv_graph_rdlock_main_loop();
2995     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
2996         bdrv_graph_rdunlock_main_loop();
2997         return;
2998     }
2999 
3000     aio_context = bdrv_get_aio_context(bs);
3001 
3002     if (!arg->has_mode) {
3003         arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
3004     }
3005 
3006     if (!arg->format) {
3007         format = (arg->mode == NEW_IMAGE_MODE_EXISTING
3008                   ? NULL : bs->drv->format_name);
3009     }
3010 
3011     flags = bs->open_flags | BDRV_O_RDWR;
3012     target_backing_bs = bdrv_cow_bs(bdrv_skip_filters(bs));
3013     if (!target_backing_bs && arg->sync == MIRROR_SYNC_MODE_TOP) {
3014         arg->sync = MIRROR_SYNC_MODE_FULL;
3015     }
3016     if (arg->sync == MIRROR_SYNC_MODE_NONE) {
3017         target_backing_bs = bs;
3018     }
3019     bdrv_graph_rdunlock_main_loop();
3020 
3021     size = bdrv_getlength(bs);
3022     if (size < 0) {
3023         error_setg_errno(errp, -size, "bdrv_getlength failed");
3024         return;
3025     }
3026 
3027     if (arg->replaces) {
3028         if (!arg->node_name) {
3029             error_setg(errp, "a node-name must be provided when replacing a"
3030                              " named node of the graph");
3031             return;
3032         }
3033     }
3034 
3035     if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
3036         backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
3037     } else {
3038         backing_mode = MIRROR_OPEN_BACKING_CHAIN;
3039     }
3040 
3041     /* Don't open backing image in create() */
3042     flags |= BDRV_O_NO_BACKING;
3043 
3044     if ((arg->sync == MIRROR_SYNC_MODE_FULL || !target_backing_bs)
3045         && arg->mode != NEW_IMAGE_MODE_EXISTING)
3046     {
3047         /* create new image w/o backing file */
3048         assert(format);
3049         bdrv_img_create(arg->target, format,
3050                         NULL, NULL, NULL, size, flags, false, &local_err);
3051     } else {
3052         BlockDriverState *explicit_backing;
3053 
3054         switch (arg->mode) {
3055         case NEW_IMAGE_MODE_EXISTING:
3056             break;
3057         case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
3058             /*
3059              * Create new image with backing file.
3060              * Implicit filters should not appear in the filename.
3061              */
3062             bdrv_graph_rdlock_main_loop();
3063             explicit_backing = bdrv_skip_implicit_filters(target_backing_bs);
3064             bdrv_refresh_filename(explicit_backing);
3065             bdrv_graph_rdunlock_main_loop();
3066 
3067             bdrv_img_create(arg->target, format,
3068                             explicit_backing->filename,
3069                             explicit_backing->drv->format_name,
3070                             NULL, size, flags, false, &local_err);
3071             break;
3072         default:
3073             abort();
3074         }
3075     }
3076 
3077     if (local_err) {
3078         error_propagate(errp, local_err);
3079         return;
3080     }
3081 
3082     options = qdict_new();
3083     if (arg->node_name) {
3084         qdict_put_str(options, "node-name", arg->node_name);
3085     }
3086     if (format) {
3087         qdict_put_str(options, "driver", format);
3088     }
3089 
3090     /* Mirroring takes care of copy-on-write using the source's backing
3091      * file.
3092      */
3093     target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
3094     if (!target_bs) {
3095         return;
3096     }
3097 
3098     bdrv_graph_rdlock_main_loop();
3099     target_is_zero = (arg->mode != NEW_IMAGE_MODE_EXISTING &&
3100                       bdrv_has_zero_init(target_bs));
3101     bdrv_graph_rdunlock_main_loop();
3102 
3103 
3104     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3105     if (ret < 0) {
3106         bdrv_unref(target_bs);
3107         return;
3108     }
3109 
3110     blockdev_mirror_common(arg->job_id, bs, target_bs,
3111                            arg->replaces, arg->sync,
3112                            backing_mode, target_is_zero,
3113                            arg->has_speed, arg->speed,
3114                            arg->has_granularity, arg->granularity,
3115                            arg->has_buf_size, arg->buf_size,
3116                            arg->has_on_source_error, arg->on_source_error,
3117                            arg->has_on_target_error, arg->on_target_error,
3118                            arg->has_unmap, arg->unmap,
3119                            NULL,
3120                            arg->has_copy_mode, arg->copy_mode,
3121                            arg->has_auto_finalize, arg->auto_finalize,
3122                            arg->has_auto_dismiss, arg->auto_dismiss,
3123                            errp);
3124     bdrv_unref(target_bs);
3125 }
3126 
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)3127 void qmp_blockdev_mirror(const char *job_id,
3128                          const char *device, const char *target,
3129                          const char *replaces,
3130                          MirrorSyncMode sync,
3131                          bool has_speed, int64_t speed,
3132                          bool has_granularity, uint32_t granularity,
3133                          bool has_buf_size, int64_t buf_size,
3134                          bool has_on_source_error,
3135                          BlockdevOnError on_source_error,
3136                          bool has_on_target_error,
3137                          BlockdevOnError on_target_error,
3138                          const char *filter_node_name,
3139                          bool has_copy_mode, MirrorCopyMode copy_mode,
3140                          bool has_auto_finalize, bool auto_finalize,
3141                          bool has_auto_dismiss, bool auto_dismiss,
3142                          bool has_target_is_zero, bool target_is_zero,
3143                          Error **errp)
3144 {
3145     BlockDriverState *bs;
3146     BlockDriverState *target_bs;
3147     AioContext *aio_context;
3148     BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
3149     int ret;
3150 
3151     bs = qmp_get_root_bs(device, errp);
3152     if (!bs) {
3153         return;
3154     }
3155 
3156     target_bs = bdrv_lookup_bs(target, target, errp);
3157     if (!target_bs) {
3158         return;
3159     }
3160 
3161     aio_context = bdrv_get_aio_context(bs);
3162 
3163     ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
3164     if (ret < 0) {
3165         return;
3166     }
3167 
3168     blockdev_mirror_common(job_id, bs, target_bs,
3169                            replaces, sync, backing_mode,
3170                            has_target_is_zero && target_is_zero,
3171                            has_speed, speed,
3172                            has_granularity, granularity,
3173                            has_buf_size, buf_size,
3174                            has_on_source_error, on_source_error,
3175                            has_on_target_error, on_target_error,
3176                            true, true, filter_node_name,
3177                            has_copy_mode, copy_mode,
3178                            has_auto_finalize, auto_finalize,
3179                            has_auto_dismiss, auto_dismiss,
3180                            errp);
3181 }
3182 
3183 /*
3184  * Get a block job using its ID. Called with job_mutex held.
3185  */
find_block_job_locked(const char * id,Error ** errp)3186 static BlockJob *find_block_job_locked(const char *id, Error **errp)
3187 {
3188     BlockJob *job;
3189 
3190     assert(id != NULL);
3191 
3192     job = block_job_get_locked(id);
3193 
3194     if (!job) {
3195         error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
3196                   "Block job '%s' not found", id);
3197         return NULL;
3198     }
3199 
3200     return job;
3201 }
3202 
qmp_block_job_set_speed(const char * device,int64_t speed,Error ** errp)3203 void qmp_block_job_set_speed(const char *device, int64_t speed, 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     block_job_set_speed_locked(job, speed, errp);
3215 }
3216 
qmp_block_job_cancel(const char * device,bool has_force,bool force,Error ** errp)3217 void qmp_block_job_cancel(const char *device,
3218                           bool has_force, bool force, Error **errp)
3219 {
3220     BlockJob *job;
3221 
3222     JOB_LOCK_GUARD();
3223     job = find_block_job_locked(device, errp);
3224 
3225     if (!job) {
3226         return;
3227     }
3228 
3229     if (!has_force) {
3230         force = false;
3231     }
3232 
3233     if (job_user_paused_locked(&job->job) && !force) {
3234         error_setg(errp, "The block job for device '%s' is currently paused",
3235                    device);
3236         return;
3237     }
3238 
3239     trace_qmp_block_job_cancel(job);
3240     job_user_cancel_locked(&job->job, force, errp);
3241 }
3242 
qmp_block_job_pause(const char * device,Error ** errp)3243 void qmp_block_job_pause(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_pause(job);
3255     job_user_pause_locked(&job->job, errp);
3256 }
3257 
qmp_block_job_resume(const char * device,Error ** errp)3258 void qmp_block_job_resume(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_resume(job);
3270     job_user_resume_locked(&job->job, errp);
3271 }
3272 
qmp_block_job_complete(const char * device,Error ** errp)3273 void qmp_block_job_complete(const char *device, Error **errp)
3274 {
3275     BlockJob *job;
3276 
3277     JOB_LOCK_GUARD();
3278     job = find_block_job_locked(device, errp);
3279 
3280     if (!job) {
3281         return;
3282     }
3283 
3284     trace_qmp_block_job_complete(job);
3285     job_complete_locked(&job->job, errp);
3286 }
3287 
qmp_block_job_finalize(const char * id,Error ** errp)3288 void qmp_block_job_finalize(const char *id, Error **errp)
3289 {
3290     BlockJob *job;
3291 
3292     JOB_LOCK_GUARD();
3293     job = find_block_job_locked(id, errp);
3294 
3295     if (!job) {
3296         return;
3297     }
3298 
3299     trace_qmp_block_job_finalize(job);
3300     job_ref_locked(&job->job);
3301     job_finalize_locked(&job->job, errp);
3302 
3303     job_unref_locked(&job->job);
3304 }
3305 
qmp_block_job_dismiss(const char * id,Error ** errp)3306 void qmp_block_job_dismiss(const char *id, Error **errp)
3307 {
3308     BlockJob *bjob;
3309     Job *job;
3310 
3311     JOB_LOCK_GUARD();
3312     bjob = find_block_job_locked(id, errp);
3313 
3314     if (!bjob) {
3315         return;
3316     }
3317 
3318     trace_qmp_block_job_dismiss(bjob);
3319     job = &bjob->job;
3320     job_dismiss_locked(&job, errp);
3321 }
3322 
qmp_block_job_change(BlockJobChangeOptions * opts,Error ** errp)3323 void qmp_block_job_change(BlockJobChangeOptions *opts, Error **errp)
3324 {
3325     BlockJob *job;
3326 
3327     JOB_LOCK_GUARD();
3328     job = find_block_job_locked(opts->id, errp);
3329 
3330     if (!job) {
3331         return;
3332     }
3333 
3334     block_job_change_locked(job, opts, errp);
3335 }
3336 
qmp_change_backing_file(const char * device,const char * image_node_name,const char * backing_file,Error ** errp)3337 void qmp_change_backing_file(const char *device,
3338                              const char *image_node_name,
3339                              const char *backing_file,
3340                              Error **errp)
3341 {
3342     BlockDriverState *bs = NULL;
3343     BlockDriverState *image_bs = NULL;
3344     Error *local_err = NULL;
3345     bool ro;
3346     int ret;
3347 
3348     bs = qmp_get_root_bs(device, errp);
3349     if (!bs) {
3350         return;
3351     }
3352 
3353     bdrv_graph_rdlock_main_loop();
3354 
3355     image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
3356     if (local_err) {
3357         error_propagate(errp, local_err);
3358         goto out_rdlock;
3359     }
3360 
3361     if (!image_bs) {
3362         error_setg(errp, "image file not found");
3363         goto out_rdlock;
3364     }
3365 
3366     if (bdrv_find_base(image_bs) == image_bs) {
3367         error_setg(errp, "not allowing backing file change on an image "
3368                          "without a backing file");
3369         goto out_rdlock;
3370     }
3371 
3372     /* even though we are not necessarily operating on bs, we need it to
3373      * determine if block ops are currently prohibited on the chain */
3374     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
3375         goto out_rdlock;
3376     }
3377 
3378     /* final sanity check */
3379     if (!bdrv_chain_contains(bs, image_bs)) {
3380         error_setg(errp, "'%s' and image file are not in the same chain",
3381                    device);
3382         goto out_rdlock;
3383     }
3384     bdrv_graph_rdunlock_main_loop();
3385 
3386     /* if not r/w, reopen to make r/w */
3387     ro = bdrv_is_read_only(image_bs);
3388 
3389     if (ro) {
3390         if (bdrv_reopen_set_read_only(image_bs, false, errp) != 0) {
3391             return;
3392         }
3393     }
3394 
3395     ret = bdrv_change_backing_file(image_bs, backing_file,
3396                                    image_bs->drv ? image_bs->drv->format_name : "",
3397                                    false);
3398 
3399     if (ret < 0) {
3400         error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
3401                          backing_file);
3402         /* don't exit here, so we can try to restore open flags if
3403          * appropriate */
3404     }
3405 
3406     if (ro) {
3407         bdrv_reopen_set_read_only(image_bs, true, errp);
3408     }
3409     return;
3410 
3411 out_rdlock:
3412     bdrv_graph_rdunlock_main_loop();
3413 }
3414 
qmp_blockdev_add(BlockdevOptions * options,Error ** errp)3415 void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
3416 {
3417     BlockDriverState *bs;
3418     QObject *obj;
3419     Visitor *v = qobject_output_visitor_new(&obj);
3420     QDict *qdict;
3421 
3422     visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3423     visit_complete(v, &obj);
3424     qdict = qobject_to(QDict, obj);
3425 
3426     qdict_flatten(qdict);
3427 
3428     if (!qdict_get_try_str(qdict, "node-name")) {
3429         error_setg(errp, "'node-name' must be specified for the root node");
3430         goto fail;
3431     }
3432 
3433     bs = bds_tree_init(qdict, errp);
3434     if (!bs) {
3435         goto fail;
3436     }
3437 
3438     bdrv_set_monitor_owned(bs);
3439 
3440 fail:
3441     visit_free(v);
3442 }
3443 
qmp_blockdev_reopen(BlockdevOptionsList * reopen_list,Error ** errp)3444 void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
3445 {
3446     BlockReopenQueue *queue = NULL;
3447 
3448     /* Add each one of the BDS that we want to reopen to the queue */
3449     for (; reopen_list != NULL; reopen_list = reopen_list->next) {
3450         BlockdevOptions *options = reopen_list->value;
3451         BlockDriverState *bs;
3452         QObject *obj;
3453         Visitor *v;
3454         QDict *qdict;
3455 
3456         /* Check for the selected node name */
3457         if (!options->node_name) {
3458             error_setg(errp, "node-name not specified");
3459             goto fail;
3460         }
3461 
3462         bs = bdrv_find_node(options->node_name);
3463         if (!bs) {
3464             error_setg(errp, "Failed to find node with node-name='%s'",
3465                        options->node_name);
3466             goto fail;
3467         }
3468 
3469         /* Put all options in a QDict and flatten it */
3470         v = qobject_output_visitor_new(&obj);
3471         visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
3472         visit_complete(v, &obj);
3473         visit_free(v);
3474 
3475         qdict = qobject_to(QDict, obj);
3476 
3477         qdict_flatten(qdict);
3478 
3479         queue = bdrv_reopen_queue(queue, bs, qdict, false);
3480     }
3481 
3482     /* Perform the reopen operation */
3483     bdrv_reopen_multiple(queue, errp);
3484     queue = NULL;
3485 
3486 fail:
3487     bdrv_reopen_queue_free(queue);
3488 }
3489 
qmp_blockdev_del(const char * node_name,Error ** errp)3490 void qmp_blockdev_del(const char *node_name, Error **errp)
3491 {
3492     BlockDriverState *bs;
3493 
3494     GLOBAL_STATE_CODE();
3495     GRAPH_RDLOCK_GUARD_MAINLOOP();
3496 
3497     bs = bdrv_find_node(node_name);
3498     if (!bs) {
3499         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3500         return;
3501     }
3502     if (bdrv_has_blk(bs)) {
3503         error_setg(errp, "Node %s is in use", node_name);
3504         return;
3505     }
3506 
3507     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
3508         return;
3509     }
3510 
3511     if (!QTAILQ_IN_USE(bs, monitor_list)) {
3512         error_setg(errp, "Node %s is not owned by the monitor",
3513                    bs->node_name);
3514         return;
3515     }
3516 
3517     if (bs->refcnt > 1) {
3518         error_setg(errp, "Block device %s is in use",
3519                    bdrv_get_device_or_node_name(bs));
3520         return;
3521     }
3522 
3523     QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
3524     bdrv_unref(bs);
3525 }
3526 
qmp_blockdev_set_active(const char * node_name,bool active,Error ** errp)3527 void qmp_blockdev_set_active(const char *node_name, bool active, Error **errp)
3528 {
3529     BlockDriverState *bs;
3530     int ret;
3531 
3532     GLOBAL_STATE_CODE();
3533 
3534     if (!node_name) {
3535         if (active) {
3536             bdrv_activate_all(errp);
3537         } else {
3538             ret = bdrv_inactivate_all();
3539             if (ret < 0) {
3540                 error_setg_errno(errp, -ret, "Failed to inactivate all nodes");
3541             }
3542         }
3543         return;
3544     }
3545 
3546     if (!active) {
3547         bdrv_drain_all_begin();
3548     }
3549     bdrv_graph_rdlock_main_loop();
3550 
3551     bs = bdrv_find_node(node_name);
3552     if (!bs) {
3553         error_setg(errp, "Failed to find node with node-name='%s'",
3554                    node_name);
3555         goto unlock;
3556     }
3557     if (active) {
3558         bdrv_activate(bs, errp);
3559     } else {
3560         bdrv_inactivate(bs, errp);
3561     }
3562 
3563 unlock:
3564     bdrv_graph_rdunlock_main_loop();
3565     if (!active) {
3566         bdrv_drain_all_end();
3567     }
3568 }
3569 
3570 static BdrvChild * GRAPH_RDLOCK
bdrv_find_child(BlockDriverState * parent_bs,const char * child_name)3571 bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
3572 {
3573     BdrvChild *child;
3574 
3575     QLIST_FOREACH(child, &parent_bs->children, next) {
3576         if (strcmp(child->name, child_name) == 0) {
3577             return child;
3578         }
3579     }
3580 
3581     return NULL;
3582 }
3583 
qmp_x_blockdev_change(const char * parent,const char * child,const char * node,Error ** errp)3584 void qmp_x_blockdev_change(const char *parent, const char *child,
3585                            const char *node, Error **errp)
3586 {
3587     BlockDriverState *parent_bs, *new_bs = NULL;
3588     BdrvChild *p_child;
3589 
3590     bdrv_graph_wrlock_drained();
3591 
3592     parent_bs = bdrv_lookup_bs(parent, parent, errp);
3593     if (!parent_bs) {
3594         goto out;
3595     }
3596 
3597     if (!child == !node) {
3598         if (child) {
3599             error_setg(errp, "The parameters child and node are in conflict");
3600         } else {
3601             error_setg(errp, "Either child or node must be specified");
3602         }
3603         goto out;
3604     }
3605 
3606     if (child) {
3607         p_child = bdrv_find_child(parent_bs, child);
3608         if (!p_child) {
3609             error_setg(errp, "Node '%s' does not have child '%s'",
3610                        parent, child);
3611             goto out;
3612         }
3613         bdrv_del_child(parent_bs, p_child, errp);
3614     }
3615 
3616     if (node) {
3617         new_bs = bdrv_find_node(node);
3618         if (!new_bs) {
3619             error_setg(errp, "Node '%s' not found", node);
3620             goto out;
3621         }
3622         bdrv_add_child(parent_bs, new_bs, errp);
3623     }
3624 
3625 out:
3626     bdrv_graph_wrunlock();
3627 }
3628 
qmp_query_block_jobs(Error ** errp)3629 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
3630 {
3631     BlockJobInfoList *head = NULL, **tail = &head;
3632     BlockJob *job;
3633 
3634     JOB_LOCK_GUARD();
3635 
3636     for (job = block_job_next_locked(NULL); job;
3637          job = block_job_next_locked(job)) {
3638         BlockJobInfo *value;
3639 
3640         if (block_job_is_internal(job)) {
3641             continue;
3642         }
3643         value = block_job_query_locked(job, errp);
3644         if (!value) {
3645             qapi_free_BlockJobInfoList(head);
3646             return NULL;
3647         }
3648         QAPI_LIST_APPEND(tail, value);
3649     }
3650 
3651     return head;
3652 }
3653 
qmp_x_blockdev_set_iothread(const char * node_name,StrOrNull * iothread,bool has_force,bool force,Error ** errp)3654 void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
3655                                  bool has_force, bool force, Error **errp)
3656 {
3657     AioContext *new_context;
3658     BlockDriverState *bs;
3659 
3660     bdrv_drain_all_begin();
3661     bdrv_graph_rdlock_main_loop();
3662 
3663     bs = bdrv_find_node(node_name);
3664     if (!bs) {
3665         error_setg(errp, "Failed to find node with node-name='%s'", node_name);
3666         goto out;
3667     }
3668 
3669     /* Protects against accidents. */
3670     if (!(has_force && force) && bdrv_has_blk(bs)) {
3671         error_setg(errp, "Node %s is associated with a BlockBackend and could "
3672                          "be in use (use force=true to override this check)",
3673                          node_name);
3674         goto out;
3675     }
3676 
3677     if (iothread->type == QTYPE_QSTRING) {
3678         IOThread *obj = iothread_by_id(iothread->u.s);
3679         if (!obj) {
3680             error_setg(errp, "Cannot find iothread %s", iothread->u.s);
3681             goto out;
3682         }
3683 
3684         new_context = iothread_get_aio_context(obj);
3685     } else {
3686         new_context = qemu_get_aio_context();
3687     }
3688 
3689     bdrv_try_change_aio_context_locked(bs, new_context, NULL, errp);
3690 
3691 out:
3692     bdrv_graph_rdunlock_main_loop();
3693     bdrv_drain_all_end();
3694 }
3695 
3696 QemuOptsList qemu_common_drive_opts = {
3697     .name = "drive",
3698     .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
3699     .desc = {
3700         {
3701             .name = "snapshot",
3702             .type = QEMU_OPT_BOOL,
3703             .help = "enable/disable snapshot mode",
3704         },{
3705             .name = "aio",
3706             .type = QEMU_OPT_STRING,
3707             .help = "host AIO implementation (threads, native, io_uring)",
3708         },{
3709             .name = BDRV_OPT_CACHE_WB,
3710             .type = QEMU_OPT_BOOL,
3711             .help = "Enable writeback mode",
3712         },{
3713             .name = "format",
3714             .type = QEMU_OPT_STRING,
3715             .help = "disk format (raw, qcow2, ...)",
3716         },{
3717             .name = "rerror",
3718             .type = QEMU_OPT_STRING,
3719             .help = "read error action",
3720         },{
3721             .name = "werror",
3722             .type = QEMU_OPT_STRING,
3723             .help = "write error action",
3724         },{
3725             .name = BDRV_OPT_READ_ONLY,
3726             .type = QEMU_OPT_BOOL,
3727             .help = "open drive file as read-only",
3728         },
3729 
3730         THROTTLE_OPTS,
3731 
3732         {
3733             .name = "throttling.group",
3734             .type = QEMU_OPT_STRING,
3735             .help = "name of the block throttling group",
3736         },{
3737             .name = "copy-on-read",
3738             .type = QEMU_OPT_BOOL,
3739             .help = "copy read data from backing file into image file",
3740         },{
3741             .name = "detect-zeroes",
3742             .type = QEMU_OPT_STRING,
3743             .help = "try to optimize zero writes (off, on, unmap)",
3744         },{
3745             .name = "stats-account-invalid",
3746             .type = QEMU_OPT_BOOL,
3747             .help = "whether to account for invalid I/O operations "
3748                     "in the statistics",
3749         },{
3750             .name = "stats-account-failed",
3751             .type = QEMU_OPT_BOOL,
3752             .help = "whether to account for failed I/O operations "
3753                     "in the statistics",
3754         },
3755         { /* end of list */ }
3756     },
3757 };
3758 
3759 QemuOptsList qemu_drive_opts = {
3760     .name = "drive",
3761     .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
3762     .desc = {
3763         /*
3764          * no elements => accept any params
3765          * validation will happen later
3766          */
3767         { /* end of list */ }
3768     },
3769 };
3770