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25#include "qemu/osdep.h"
26#include "block/snapshot.h"
27#include "block/block_int.h"
28#include "qapi/error.h"
29#include "qapi/qmp/qdict.h"
30#include "qapi/qmp/qerror.h"
31#include "qapi/qmp/qstring.h"
32#include "qemu/option.h"
33
34QemuOptsList internal_snapshot_opts = {
35 .name = "snapshot",
36 .head = QTAILQ_HEAD_INITIALIZER(internal_snapshot_opts.head),
37 .desc = {
38 {
39 .name = SNAPSHOT_OPT_ID,
40 .type = QEMU_OPT_STRING,
41 .help = "snapshot id"
42 },{
43 .name = SNAPSHOT_OPT_NAME,
44 .type = QEMU_OPT_STRING,
45 .help = "snapshot name"
46 },{
47
48 }
49 },
50};
51
52int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
53 const char *name)
54{
55 QEMUSnapshotInfo *sn_tab, *sn;
56 int nb_sns, i, ret;
57
58 ret = -ENOENT;
59 nb_sns = bdrv_snapshot_list(bs, &sn_tab);
60 if (nb_sns < 0) {
61 return ret;
62 }
63 for (i = 0; i < nb_sns; i++) {
64 sn = &sn_tab[i];
65 if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
66 *sn_info = *sn;
67 ret = 0;
68 break;
69 }
70 }
71 g_free(sn_tab);
72 return ret;
73}
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95bool bdrv_snapshot_find_by_id_and_name(BlockDriverState *bs,
96 const char *id,
97 const char *name,
98 QEMUSnapshotInfo *sn_info,
99 Error **errp)
100{
101 QEMUSnapshotInfo *sn_tab, *sn;
102 int nb_sns, i;
103 bool ret = false;
104
105 assert(id || name);
106
107 nb_sns = bdrv_snapshot_list(bs, &sn_tab);
108 if (nb_sns < 0) {
109 error_setg_errno(errp, -nb_sns, "Failed to get a snapshot list");
110 return false;
111 } else if (nb_sns == 0) {
112 return false;
113 }
114
115 if (id && name) {
116 for (i = 0; i < nb_sns; i++) {
117 sn = &sn_tab[i];
118 if (!strcmp(sn->id_str, id) && !strcmp(sn->name, name)) {
119 *sn_info = *sn;
120 ret = true;
121 break;
122 }
123 }
124 } else if (id) {
125 for (i = 0; i < nb_sns; i++) {
126 sn = &sn_tab[i];
127 if (!strcmp(sn->id_str, id)) {
128 *sn_info = *sn;
129 ret = true;
130 break;
131 }
132 }
133 } else if (name) {
134 for (i = 0; i < nb_sns; i++) {
135 sn = &sn_tab[i];
136 if (!strcmp(sn->name, name)) {
137 *sn_info = *sn;
138 ret = true;
139 break;
140 }
141 }
142 }
143
144 g_free(sn_tab);
145 return ret;
146}
147
148int bdrv_can_snapshot(BlockDriverState *bs)
149{
150 BlockDriver *drv = bs->drv;
151 if (!drv || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
152 return 0;
153 }
154
155 if (!drv->bdrv_snapshot_create) {
156 if (bs->file != NULL) {
157 return bdrv_can_snapshot(bs->file->bs);
158 }
159 return 0;
160 }
161
162 return 1;
163}
164
165int bdrv_snapshot_create(BlockDriverState *bs,
166 QEMUSnapshotInfo *sn_info)
167{
168 BlockDriver *drv = bs->drv;
169 if (!drv) {
170 return -ENOMEDIUM;
171 }
172 if (drv->bdrv_snapshot_create) {
173 return drv->bdrv_snapshot_create(bs, sn_info);
174 }
175 if (bs->file) {
176 return bdrv_snapshot_create(bs->file->bs, sn_info);
177 }
178 return -ENOTSUP;
179}
180
181int bdrv_snapshot_goto(BlockDriverState *bs,
182 const char *snapshot_id,
183 Error **errp)
184{
185 BlockDriver *drv = bs->drv;
186 int ret, open_ret;
187
188 if (!drv) {
189 error_setg(errp, "Block driver is closed");
190 return -ENOMEDIUM;
191 }
192
193 if (!QLIST_EMPTY(&bs->dirty_bitmaps)) {
194 error_setg(errp, "Device has active dirty bitmaps");
195 return -EBUSY;
196 }
197
198 if (drv->bdrv_snapshot_goto) {
199 ret = drv->bdrv_snapshot_goto(bs, snapshot_id);
200 if (ret < 0) {
201 error_setg_errno(errp, -ret, "Failed to load snapshot");
202 }
203 return ret;
204 }
205
206 if (bs->file) {
207 BlockDriverState *file;
208 QDict *options = qdict_clone_shallow(bs->options);
209 QDict *file_options;
210 Error *local_err = NULL;
211
212 file = bs->file->bs;
213
214 bdrv_ref(file);
215
216 qdict_extract_subqdict(options, &file_options, "file.");
217 QDECREF(file_options);
218 qdict_put_str(options, "file", bdrv_get_node_name(file));
219
220 drv->bdrv_close(bs);
221 bdrv_unref_child(bs, bs->file);
222 bs->file = NULL;
223
224 ret = bdrv_snapshot_goto(file, snapshot_id, errp);
225 open_ret = drv->bdrv_open(bs, options, bs->open_flags, &local_err);
226 QDECREF(options);
227 if (open_ret < 0) {
228 bdrv_unref(file);
229 bs->drv = NULL;
230
231 error_propagate(errp, local_err);
232 return ret < 0 ? ret : open_ret;
233 }
234
235 assert(bs->file->bs == file);
236 bdrv_unref(file);
237 return ret;
238 }
239
240 error_setg(errp, "Block driver does not support snapshots");
241 return -ENOTSUP;
242}
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266int bdrv_snapshot_delete(BlockDriverState *bs,
267 const char *snapshot_id,
268 const char *name,
269 Error **errp)
270{
271 BlockDriver *drv = bs->drv;
272 int ret;
273
274 if (!drv) {
275 error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, bdrv_get_device_name(bs));
276 return -ENOMEDIUM;
277 }
278 if (!snapshot_id && !name) {
279 error_setg(errp, "snapshot_id and name are both NULL");
280 return -EINVAL;
281 }
282
283
284 bdrv_drained_begin(bs);
285
286 if (drv->bdrv_snapshot_delete) {
287 ret = drv->bdrv_snapshot_delete(bs, snapshot_id, name, errp);
288 } else if (bs->file) {
289 ret = bdrv_snapshot_delete(bs->file->bs, snapshot_id, name, errp);
290 } else {
291 error_setg(errp, "Block format '%s' used by device '%s' "
292 "does not support internal snapshot deletion",
293 drv->format_name, bdrv_get_device_name(bs));
294 ret = -ENOTSUP;
295 }
296
297 bdrv_drained_end(bs);
298 return ret;
299}
300
301int bdrv_snapshot_delete_by_id_or_name(BlockDriverState *bs,
302 const char *id_or_name,
303 Error **errp)
304{
305 int ret;
306 Error *local_err = NULL;
307
308 ret = bdrv_snapshot_delete(bs, id_or_name, NULL, &local_err);
309 if (ret == -ENOENT || ret == -EINVAL) {
310 error_free(local_err);
311 local_err = NULL;
312 ret = bdrv_snapshot_delete(bs, NULL, id_or_name, &local_err);
313 }
314
315 if (ret < 0) {
316 error_propagate(errp, local_err);
317 }
318 return ret;
319}
320
321int bdrv_snapshot_list(BlockDriverState *bs,
322 QEMUSnapshotInfo **psn_info)
323{
324 BlockDriver *drv = bs->drv;
325 if (!drv) {
326 return -ENOMEDIUM;
327 }
328 if (drv->bdrv_snapshot_list) {
329 return drv->bdrv_snapshot_list(bs, psn_info);
330 }
331 if (bs->file) {
332 return bdrv_snapshot_list(bs->file->bs, psn_info);
333 }
334 return -ENOTSUP;
335}
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357int bdrv_snapshot_load_tmp(BlockDriverState *bs,
358 const char *snapshot_id,
359 const char *name,
360 Error **errp)
361{
362 BlockDriver *drv = bs->drv;
363
364 if (!drv) {
365 error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, bdrv_get_device_name(bs));
366 return -ENOMEDIUM;
367 }
368 if (!snapshot_id && !name) {
369 error_setg(errp, "snapshot_id and name are both NULL");
370 return -EINVAL;
371 }
372 if (!bs->read_only) {
373 error_setg(errp, "Device is not readonly");
374 return -EINVAL;
375 }
376 if (drv->bdrv_snapshot_load_tmp) {
377 return drv->bdrv_snapshot_load_tmp(bs, snapshot_id, name, errp);
378 }
379 error_setg(errp, "Block format '%s' used by device '%s' "
380 "does not support temporarily loading internal snapshots",
381 drv->format_name, bdrv_get_device_name(bs));
382 return -ENOTSUP;
383}
384
385int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs,
386 const char *id_or_name,
387 Error **errp)
388{
389 int ret;
390 Error *local_err = NULL;
391
392 ret = bdrv_snapshot_load_tmp(bs, id_or_name, NULL, &local_err);
393 if (ret == -ENOENT || ret == -EINVAL) {
394 error_free(local_err);
395 local_err = NULL;
396 ret = bdrv_snapshot_load_tmp(bs, NULL, id_or_name, &local_err);
397 }
398
399 error_propagate(errp, local_err);
400
401 return ret;
402}
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409bool bdrv_all_can_snapshot(BlockDriverState **first_bad_bs)
410{
411 bool ok = true;
412 BlockDriverState *bs;
413 BdrvNextIterator it;
414
415 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
416 AioContext *ctx = bdrv_get_aio_context(bs);
417
418 aio_context_acquire(ctx);
419 if (bdrv_is_inserted(bs) && !bdrv_is_read_only(bs)) {
420 ok = bdrv_can_snapshot(bs);
421 }
422 aio_context_release(ctx);
423 if (!ok) {
424 bdrv_next_cleanup(&it);
425 goto fail;
426 }
427 }
428
429fail:
430 *first_bad_bs = bs;
431 return ok;
432}
433
434int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bad_bs,
435 Error **err)
436{
437 int ret = 0;
438 BlockDriverState *bs;
439 BdrvNextIterator it;
440 QEMUSnapshotInfo sn1, *snapshot = &sn1;
441
442 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
443 AioContext *ctx = bdrv_get_aio_context(bs);
444
445 aio_context_acquire(ctx);
446 if (bdrv_can_snapshot(bs) &&
447 bdrv_snapshot_find(bs, snapshot, name) >= 0) {
448 ret = bdrv_snapshot_delete_by_id_or_name(bs, name, err);
449 }
450 aio_context_release(ctx);
451 if (ret < 0) {
452 bdrv_next_cleanup(&it);
453 goto fail;
454 }
455 }
456
457fail:
458 *first_bad_bs = bs;
459 return ret;
460}
461
462
463int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bad_bs,
464 Error **errp)
465{
466 int ret = 0;
467 BlockDriverState *bs;
468 BdrvNextIterator it;
469
470 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
471 AioContext *ctx = bdrv_get_aio_context(bs);
472
473 aio_context_acquire(ctx);
474 if (bdrv_can_snapshot(bs)) {
475 ret = bdrv_snapshot_goto(bs, name, errp);
476 }
477 aio_context_release(ctx);
478 if (ret < 0) {
479 bdrv_next_cleanup(&it);
480 goto fail;
481 }
482 }
483
484fail:
485 *first_bad_bs = bs;
486 return ret;
487}
488
489int bdrv_all_find_snapshot(const char *name, BlockDriverState **first_bad_bs)
490{
491 QEMUSnapshotInfo sn;
492 int err = 0;
493 BlockDriverState *bs;
494 BdrvNextIterator it;
495
496 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
497 AioContext *ctx = bdrv_get_aio_context(bs);
498
499 aio_context_acquire(ctx);
500 if (bdrv_can_snapshot(bs)) {
501 err = bdrv_snapshot_find(bs, &sn, name);
502 }
503 aio_context_release(ctx);
504 if (err < 0) {
505 bdrv_next_cleanup(&it);
506 goto fail;
507 }
508 }
509
510fail:
511 *first_bad_bs = bs;
512 return err;
513}
514
515int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
516 BlockDriverState *vm_state_bs,
517 uint64_t vm_state_size,
518 BlockDriverState **first_bad_bs)
519{
520 int err = 0;
521 BlockDriverState *bs;
522 BdrvNextIterator it;
523
524 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
525 AioContext *ctx = bdrv_get_aio_context(bs);
526
527 aio_context_acquire(ctx);
528 if (bs == vm_state_bs) {
529 sn->vm_state_size = vm_state_size;
530 err = bdrv_snapshot_create(bs, sn);
531 } else if (bdrv_can_snapshot(bs)) {
532 sn->vm_state_size = 0;
533 err = bdrv_snapshot_create(bs, sn);
534 }
535 aio_context_release(ctx);
536 if (err < 0) {
537 bdrv_next_cleanup(&it);
538 goto fail;
539 }
540 }
541
542fail:
543 *first_bad_bs = bs;
544 return err;
545}
546
547BlockDriverState *bdrv_all_find_vmstate_bs(void)
548{
549 BlockDriverState *bs;
550 BdrvNextIterator it;
551
552 for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
553 AioContext *ctx = bdrv_get_aio_context(bs);
554 bool found;
555
556 aio_context_acquire(ctx);
557 found = bdrv_can_snapshot(bs);
558 aio_context_release(ctx);
559
560 if (found) {
561 bdrv_next_cleanup(&it);
562 break;
563 }
564 }
565 return bs;
566}
567