xref: /openbmc/qemu/block/qapi.c (revision 77a8257e)
1 /*
2  * Block layer qmp and info dump related functions
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "block/qapi.h"
26 #include "block/block_int.h"
27 #include "block/write-threshold.h"
28 #include "qmp-commands.h"
29 #include "qapi-visit.h"
30 #include "qapi/qmp-output-visitor.h"
31 #include "qapi/qmp/types.h"
32 #include "sysemu/block-backend.h"
33 
34 BlockDeviceInfo *bdrv_block_device_info(BlockDriverState *bs)
35 {
36     BlockDeviceInfo *info = g_malloc0(sizeof(*info));
37 
38     info->file                   = g_strdup(bs->filename);
39     info->ro                     = bs->read_only;
40     info->drv                    = g_strdup(bs->drv->format_name);
41     info->encrypted              = bs->encrypted;
42     info->encryption_key_missing = bdrv_key_required(bs);
43 
44     info->cache = g_new(BlockdevCacheInfo, 1);
45     *info->cache = (BlockdevCacheInfo) {
46         .writeback      = bdrv_enable_write_cache(bs),
47         .direct         = !!(bs->open_flags & BDRV_O_NOCACHE),
48         .no_flush       = !!(bs->open_flags & BDRV_O_NO_FLUSH),
49     };
50 
51     if (bs->node_name[0]) {
52         info->has_node_name = true;
53         info->node_name = g_strdup(bs->node_name);
54     }
55 
56     if (bs->backing_file[0]) {
57         info->has_backing_file = true;
58         info->backing_file = g_strdup(bs->backing_file);
59     }
60 
61     info->backing_file_depth = bdrv_get_backing_file_depth(bs);
62     info->detect_zeroes = bs->detect_zeroes;
63 
64     if (bs->io_limits_enabled) {
65         ThrottleConfig cfg;
66         throttle_get_config(&bs->throttle_state, &cfg);
67         info->bps     = cfg.buckets[THROTTLE_BPS_TOTAL].avg;
68         info->bps_rd  = cfg.buckets[THROTTLE_BPS_READ].avg;
69         info->bps_wr  = cfg.buckets[THROTTLE_BPS_WRITE].avg;
70 
71         info->iops    = cfg.buckets[THROTTLE_OPS_TOTAL].avg;
72         info->iops_rd = cfg.buckets[THROTTLE_OPS_READ].avg;
73         info->iops_wr = cfg.buckets[THROTTLE_OPS_WRITE].avg;
74 
75         info->has_bps_max     = cfg.buckets[THROTTLE_BPS_TOTAL].max;
76         info->bps_max         = cfg.buckets[THROTTLE_BPS_TOTAL].max;
77         info->has_bps_rd_max  = cfg.buckets[THROTTLE_BPS_READ].max;
78         info->bps_rd_max      = cfg.buckets[THROTTLE_BPS_READ].max;
79         info->has_bps_wr_max  = cfg.buckets[THROTTLE_BPS_WRITE].max;
80         info->bps_wr_max      = cfg.buckets[THROTTLE_BPS_WRITE].max;
81 
82         info->has_iops_max    = cfg.buckets[THROTTLE_OPS_TOTAL].max;
83         info->iops_max        = cfg.buckets[THROTTLE_OPS_TOTAL].max;
84         info->has_iops_rd_max = cfg.buckets[THROTTLE_OPS_READ].max;
85         info->iops_rd_max     = cfg.buckets[THROTTLE_OPS_READ].max;
86         info->has_iops_wr_max = cfg.buckets[THROTTLE_OPS_WRITE].max;
87         info->iops_wr_max     = cfg.buckets[THROTTLE_OPS_WRITE].max;
88 
89         info->has_iops_size = cfg.op_size;
90         info->iops_size = cfg.op_size;
91     }
92 
93     info->write_threshold = bdrv_write_threshold_get(bs);
94 
95     return info;
96 }
97 
98 /*
99  * Returns 0 on success, with *p_list either set to describe snapshot
100  * information, or NULL because there are no snapshots.  Returns -errno on
101  * error, with *p_list untouched.
102  */
103 int bdrv_query_snapshot_info_list(BlockDriverState *bs,
104                                   SnapshotInfoList **p_list,
105                                   Error **errp)
106 {
107     int i, sn_count;
108     QEMUSnapshotInfo *sn_tab = NULL;
109     SnapshotInfoList *info_list, *cur_item = NULL, *head = NULL;
110     SnapshotInfo *info;
111 
112     sn_count = bdrv_snapshot_list(bs, &sn_tab);
113     if (sn_count < 0) {
114         const char *dev = bdrv_get_device_name(bs);
115         switch (sn_count) {
116         case -ENOMEDIUM:
117             error_setg(errp, "Device '%s' is not inserted", dev);
118             break;
119         case -ENOTSUP:
120             error_setg(errp,
121                        "Device '%s' does not support internal snapshots",
122                        dev);
123             break;
124         default:
125             error_setg_errno(errp, -sn_count,
126                              "Can't list snapshots of device '%s'", dev);
127             break;
128         }
129         return sn_count;
130     }
131 
132     for (i = 0; i < sn_count; i++) {
133         info = g_new0(SnapshotInfo, 1);
134         info->id            = g_strdup(sn_tab[i].id_str);
135         info->name          = g_strdup(sn_tab[i].name);
136         info->vm_state_size = sn_tab[i].vm_state_size;
137         info->date_sec      = sn_tab[i].date_sec;
138         info->date_nsec     = sn_tab[i].date_nsec;
139         info->vm_clock_sec  = sn_tab[i].vm_clock_nsec / 1000000000;
140         info->vm_clock_nsec = sn_tab[i].vm_clock_nsec % 1000000000;
141 
142         info_list = g_new0(SnapshotInfoList, 1);
143         info_list->value = info;
144 
145         /* XXX: waiting for the qapi to support qemu-queue.h types */
146         if (!cur_item) {
147             head = cur_item = info_list;
148         } else {
149             cur_item->next = info_list;
150             cur_item = info_list;
151         }
152 
153     }
154 
155     g_free(sn_tab);
156     *p_list = head;
157     return 0;
158 }
159 
160 /**
161  * bdrv_query_image_info:
162  * @bs: block device to examine
163  * @p_info: location to store image information
164  * @errp: location to store error information
165  *
166  * Store "flat" image information in @p_info.
167  *
168  * "Flat" means it does *not* query backing image information,
169  * i.e. (*pinfo)->has_backing_image will be set to false and
170  * (*pinfo)->backing_image to NULL even when the image does in fact have
171  * a backing image.
172  *
173  * @p_info will be set only on success. On error, store error in @errp.
174  */
175 void bdrv_query_image_info(BlockDriverState *bs,
176                            ImageInfo **p_info,
177                            Error **errp)
178 {
179     int64_t size;
180     const char *backing_filename;
181     BlockDriverInfo bdi;
182     int ret;
183     Error *err = NULL;
184     ImageInfo *info;
185 
186     size = bdrv_getlength(bs);
187     if (size < 0) {
188         error_setg_errno(errp, -size, "Can't get size of device '%s'",
189                          bdrv_get_device_name(bs));
190         return;
191     }
192 
193     info = g_new0(ImageInfo, 1);
194     info->filename        = g_strdup(bs->filename);
195     info->format          = g_strdup(bdrv_get_format_name(bs));
196     info->virtual_size    = size;
197     info->actual_size     = bdrv_get_allocated_file_size(bs);
198     info->has_actual_size = info->actual_size >= 0;
199     if (bdrv_is_encrypted(bs)) {
200         info->encrypted = true;
201         info->has_encrypted = true;
202     }
203     if (bdrv_get_info(bs, &bdi) >= 0) {
204         if (bdi.cluster_size != 0) {
205             info->cluster_size = bdi.cluster_size;
206             info->has_cluster_size = true;
207         }
208         info->dirty_flag = bdi.is_dirty;
209         info->has_dirty_flag = true;
210     }
211     info->format_specific     = bdrv_get_specific_info(bs);
212     info->has_format_specific = info->format_specific != NULL;
213 
214     backing_filename = bs->backing_file;
215     if (backing_filename[0] != '\0') {
216         char *backing_filename2 = g_malloc0(PATH_MAX);
217         info->backing_filename = g_strdup(backing_filename);
218         info->has_backing_filename = true;
219         bdrv_get_full_backing_filename(bs, backing_filename2, PATH_MAX, &err);
220         if (err) {
221             error_propagate(errp, err);
222             qapi_free_ImageInfo(info);
223             g_free(backing_filename2);
224             return;
225         }
226 
227         if (strcmp(backing_filename, backing_filename2) != 0) {
228             info->full_backing_filename =
229                         g_strdup(backing_filename2);
230             info->has_full_backing_filename = true;
231         }
232 
233         if (bs->backing_format[0]) {
234             info->backing_filename_format = g_strdup(bs->backing_format);
235             info->has_backing_filename_format = true;
236         }
237         g_free(backing_filename2);
238     }
239 
240     ret = bdrv_query_snapshot_info_list(bs, &info->snapshots, &err);
241     switch (ret) {
242     case 0:
243         if (info->snapshots) {
244             info->has_snapshots = true;
245         }
246         break;
247     /* recoverable error */
248     case -ENOMEDIUM:
249     case -ENOTSUP:
250         error_free(err);
251         break;
252     default:
253         error_propagate(errp, err);
254         qapi_free_ImageInfo(info);
255         return;
256     }
257 
258     *p_info = info;
259 }
260 
261 /* @p_info will be set only on success. */
262 static void bdrv_query_info(BlockBackend *blk, BlockInfo **p_info,
263                             Error **errp)
264 {
265     BlockInfo *info = g_malloc0(sizeof(*info));
266     BlockDriverState *bs = blk_bs(blk);
267     BlockDriverState *bs0;
268     ImageInfo **p_image_info;
269     Error *local_err = NULL;
270     info->device = g_strdup(blk_name(blk));
271     info->type = g_strdup("unknown");
272     info->locked = blk_dev_is_medium_locked(blk);
273     info->removable = blk_dev_has_removable_media(blk);
274 
275     if (blk_dev_has_removable_media(blk)) {
276         info->has_tray_open = true;
277         info->tray_open = blk_dev_is_tray_open(blk);
278     }
279 
280     if (bdrv_iostatus_is_enabled(bs)) {
281         info->has_io_status = true;
282         info->io_status = bs->iostatus;
283     }
284 
285     if (!QLIST_EMPTY(&bs->dirty_bitmaps)) {
286         info->has_dirty_bitmaps = true;
287         info->dirty_bitmaps = bdrv_query_dirty_bitmaps(bs);
288     }
289 
290     if (bs->drv) {
291         info->has_inserted = true;
292         info->inserted = bdrv_block_device_info(bs);
293 
294         bs0 = bs;
295         p_image_info = &info->inserted->image;
296         while (1) {
297             bdrv_query_image_info(bs0, p_image_info, &local_err);
298             if (local_err) {
299                 error_propagate(errp, local_err);
300                 goto err;
301             }
302             if (bs0->drv && bs0->backing_hd) {
303                 bs0 = bs0->backing_hd;
304                 (*p_image_info)->has_backing_image = true;
305                 p_image_info = &((*p_image_info)->backing_image);
306             } else {
307                 break;
308             }
309         }
310     }
311 
312     *p_info = info;
313     return;
314 
315  err:
316     qapi_free_BlockInfo(info);
317 }
318 
319 static BlockStats *bdrv_query_stats(const BlockDriverState *bs,
320                                     bool query_backing)
321 {
322     BlockStats *s;
323 
324     s = g_malloc0(sizeof(*s));
325 
326     if (bdrv_get_device_name(bs)[0]) {
327         s->has_device = true;
328         s->device = g_strdup(bdrv_get_device_name(bs));
329     }
330 
331     if (bdrv_get_node_name(bs)[0]) {
332         s->has_node_name = true;
333         s->node_name = g_strdup(bdrv_get_node_name(bs));
334     }
335 
336     s->stats = g_malloc0(sizeof(*s->stats));
337     s->stats->rd_bytes = bs->stats.nr_bytes[BLOCK_ACCT_READ];
338     s->stats->wr_bytes = bs->stats.nr_bytes[BLOCK_ACCT_WRITE];
339     s->stats->rd_operations = bs->stats.nr_ops[BLOCK_ACCT_READ];
340     s->stats->wr_operations = bs->stats.nr_ops[BLOCK_ACCT_WRITE];
341     s->stats->rd_merged = bs->stats.merged[BLOCK_ACCT_READ];
342     s->stats->wr_merged = bs->stats.merged[BLOCK_ACCT_WRITE];
343     s->stats->wr_highest_offset =
344         bs->stats.wr_highest_sector * BDRV_SECTOR_SIZE;
345     s->stats->flush_operations = bs->stats.nr_ops[BLOCK_ACCT_FLUSH];
346     s->stats->wr_total_time_ns = bs->stats.total_time_ns[BLOCK_ACCT_WRITE];
347     s->stats->rd_total_time_ns = bs->stats.total_time_ns[BLOCK_ACCT_READ];
348     s->stats->flush_total_time_ns = bs->stats.total_time_ns[BLOCK_ACCT_FLUSH];
349 
350     if (bs->file) {
351         s->has_parent = true;
352         s->parent = bdrv_query_stats(bs->file, query_backing);
353     }
354 
355     if (query_backing && bs->backing_hd) {
356         s->has_backing = true;
357         s->backing = bdrv_query_stats(bs->backing_hd, query_backing);
358     }
359 
360     return s;
361 }
362 
363 BlockInfoList *qmp_query_block(Error **errp)
364 {
365     BlockInfoList *head = NULL, **p_next = &head;
366     BlockBackend *blk;
367     Error *local_err = NULL;
368 
369     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
370         BlockInfoList *info = g_malloc0(sizeof(*info));
371         bdrv_query_info(blk, &info->value, &local_err);
372         if (local_err) {
373             error_propagate(errp, local_err);
374             goto err;
375         }
376 
377         *p_next = info;
378         p_next = &info->next;
379     }
380 
381     return head;
382 
383  err:
384     qapi_free_BlockInfoList(head);
385     return NULL;
386 }
387 
388 BlockStatsList *qmp_query_blockstats(bool has_query_nodes,
389                                      bool query_nodes,
390                                      Error **errp)
391 {
392     BlockStatsList *head = NULL, **p_next = &head;
393     BlockDriverState *bs = NULL;
394 
395     /* Just to be safe if query_nodes is not always initialized */
396     query_nodes = has_query_nodes && query_nodes;
397 
398     while ((bs = query_nodes ? bdrv_next_node(bs) : bdrv_next(bs))) {
399         BlockStatsList *info = g_malloc0(sizeof(*info));
400         AioContext *ctx = bdrv_get_aio_context(bs);
401 
402         aio_context_acquire(ctx);
403         info->value = bdrv_query_stats(bs, !query_nodes);
404         aio_context_release(ctx);
405 
406         *p_next = info;
407         p_next = &info->next;
408     }
409 
410     return head;
411 }
412 
413 #define NB_SUFFIXES 4
414 
415 static char *get_human_readable_size(char *buf, int buf_size, int64_t size)
416 {
417     static const char suffixes[NB_SUFFIXES] = "KMGT";
418     int64_t base;
419     int i;
420 
421     if (size <= 999) {
422         snprintf(buf, buf_size, "%" PRId64, size);
423     } else {
424         base = 1024;
425         for (i = 0; i < NB_SUFFIXES; i++) {
426             if (size < (10 * base)) {
427                 snprintf(buf, buf_size, "%0.1f%c",
428                          (double)size / base,
429                          suffixes[i]);
430                 break;
431             } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
432                 snprintf(buf, buf_size, "%" PRId64 "%c",
433                          ((size + (base >> 1)) / base),
434                          suffixes[i]);
435                 break;
436             }
437             base = base * 1024;
438         }
439     }
440     return buf;
441 }
442 
443 void bdrv_snapshot_dump(fprintf_function func_fprintf, void *f,
444                         QEMUSnapshotInfo *sn)
445 {
446     char buf1[128], date_buf[128], clock_buf[128];
447     struct tm tm;
448     time_t ti;
449     int64_t secs;
450 
451     if (!sn) {
452         func_fprintf(f,
453                      "%-10s%-20s%7s%20s%15s",
454                      "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
455     } else {
456         ti = sn->date_sec;
457         localtime_r(&ti, &tm);
458         strftime(date_buf, sizeof(date_buf),
459                  "%Y-%m-%d %H:%M:%S", &tm);
460         secs = sn->vm_clock_nsec / 1000000000;
461         snprintf(clock_buf, sizeof(clock_buf),
462                  "%02d:%02d:%02d.%03d",
463                  (int)(secs / 3600),
464                  (int)((secs / 60) % 60),
465                  (int)(secs % 60),
466                  (int)((sn->vm_clock_nsec / 1000000) % 1000));
467         func_fprintf(f,
468                      "%-10s%-20s%7s%20s%15s",
469                      sn->id_str, sn->name,
470                      get_human_readable_size(buf1, sizeof(buf1),
471                                              sn->vm_state_size),
472                      date_buf,
473                      clock_buf);
474     }
475 }
476 
477 static void dump_qdict(fprintf_function func_fprintf, void *f, int indentation,
478                        QDict *dict);
479 static void dump_qlist(fprintf_function func_fprintf, void *f, int indentation,
480                        QList *list);
481 
482 static void dump_qobject(fprintf_function func_fprintf, void *f,
483                          int comp_indent, QObject *obj)
484 {
485     switch (qobject_type(obj)) {
486         case QTYPE_QINT: {
487             QInt *value = qobject_to_qint(obj);
488             func_fprintf(f, "%" PRId64, qint_get_int(value));
489             break;
490         }
491         case QTYPE_QSTRING: {
492             QString *value = qobject_to_qstring(obj);
493             func_fprintf(f, "%s", qstring_get_str(value));
494             break;
495         }
496         case QTYPE_QDICT: {
497             QDict *value = qobject_to_qdict(obj);
498             dump_qdict(func_fprintf, f, comp_indent, value);
499             break;
500         }
501         case QTYPE_QLIST: {
502             QList *value = qobject_to_qlist(obj);
503             dump_qlist(func_fprintf, f, comp_indent, value);
504             break;
505         }
506         case QTYPE_QFLOAT: {
507             QFloat *value = qobject_to_qfloat(obj);
508             func_fprintf(f, "%g", qfloat_get_double(value));
509             break;
510         }
511         case QTYPE_QBOOL: {
512             QBool *value = qobject_to_qbool(obj);
513             func_fprintf(f, "%s", qbool_get_int(value) ? "true" : "false");
514             break;
515         }
516         case QTYPE_QERROR: {
517             QString *value = qerror_human((QError *)obj);
518             func_fprintf(f, "%s", qstring_get_str(value));
519             QDECREF(value);
520             break;
521         }
522         case QTYPE_NONE:
523             break;
524         case QTYPE_MAX:
525         default:
526             abort();
527     }
528 }
529 
530 static void dump_qlist(fprintf_function func_fprintf, void *f, int indentation,
531                        QList *list)
532 {
533     const QListEntry *entry;
534     int i = 0;
535 
536     for (entry = qlist_first(list); entry; entry = qlist_next(entry), i++) {
537         qtype_code type = qobject_type(entry->value);
538         bool composite = (type == QTYPE_QDICT || type == QTYPE_QLIST);
539         const char *format = composite ? "%*s[%i]:\n" : "%*s[%i]: ";
540 
541         func_fprintf(f, format, indentation * 4, "", i);
542         dump_qobject(func_fprintf, f, indentation + 1, entry->value);
543         if (!composite) {
544             func_fprintf(f, "\n");
545         }
546     }
547 }
548 
549 static void dump_qdict(fprintf_function func_fprintf, void *f, int indentation,
550                        QDict *dict)
551 {
552     const QDictEntry *entry;
553 
554     for (entry = qdict_first(dict); entry; entry = qdict_next(dict, entry)) {
555         qtype_code type = qobject_type(entry->value);
556         bool composite = (type == QTYPE_QDICT || type == QTYPE_QLIST);
557         const char *format = composite ? "%*s%s:\n" : "%*s%s: ";
558         char key[strlen(entry->key) + 1];
559         int i;
560 
561         /* replace dashes with spaces in key (variable) names */
562         for (i = 0; entry->key[i]; i++) {
563             key[i] = entry->key[i] == '-' ? ' ' : entry->key[i];
564         }
565         key[i] = 0;
566 
567         func_fprintf(f, format, indentation * 4, "", key);
568         dump_qobject(func_fprintf, f, indentation + 1, entry->value);
569         if (!composite) {
570             func_fprintf(f, "\n");
571         }
572     }
573 }
574 
575 void bdrv_image_info_specific_dump(fprintf_function func_fprintf, void *f,
576                                    ImageInfoSpecific *info_spec)
577 {
578     QmpOutputVisitor *ov = qmp_output_visitor_new();
579     QObject *obj, *data;
580 
581     visit_type_ImageInfoSpecific(qmp_output_get_visitor(ov), &info_spec, NULL,
582                                  &error_abort);
583     obj = qmp_output_get_qobject(ov);
584     assert(qobject_type(obj) == QTYPE_QDICT);
585     data = qdict_get(qobject_to_qdict(obj), "data");
586     dump_qobject(func_fprintf, f, 1, data);
587     qmp_output_visitor_cleanup(ov);
588 }
589 
590 void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
591                           ImageInfo *info)
592 {
593     char size_buf[128], dsize_buf[128];
594     if (!info->has_actual_size) {
595         snprintf(dsize_buf, sizeof(dsize_buf), "unavailable");
596     } else {
597         get_human_readable_size(dsize_buf, sizeof(dsize_buf),
598                                 info->actual_size);
599     }
600     get_human_readable_size(size_buf, sizeof(size_buf), info->virtual_size);
601     func_fprintf(f,
602                  "image: %s\n"
603                  "file format: %s\n"
604                  "virtual size: %s (%" PRId64 " bytes)\n"
605                  "disk size: %s\n",
606                  info->filename, info->format, size_buf,
607                  info->virtual_size,
608                  dsize_buf);
609 
610     if (info->has_encrypted && info->encrypted) {
611         func_fprintf(f, "encrypted: yes\n");
612     }
613 
614     if (info->has_cluster_size) {
615         func_fprintf(f, "cluster_size: %" PRId64 "\n",
616                        info->cluster_size);
617     }
618 
619     if (info->has_dirty_flag && info->dirty_flag) {
620         func_fprintf(f, "cleanly shut down: no\n");
621     }
622 
623     if (info->has_backing_filename) {
624         func_fprintf(f, "backing file: %s", info->backing_filename);
625         if (info->has_full_backing_filename) {
626             func_fprintf(f, " (actual path: %s)", info->full_backing_filename);
627         }
628         func_fprintf(f, "\n");
629         if (info->has_backing_filename_format) {
630             func_fprintf(f, "backing file format: %s\n",
631                          info->backing_filename_format);
632         }
633     }
634 
635     if (info->has_snapshots) {
636         SnapshotInfoList *elem;
637 
638         func_fprintf(f, "Snapshot list:\n");
639         bdrv_snapshot_dump(func_fprintf, f, NULL);
640         func_fprintf(f, "\n");
641 
642         /* Ideally bdrv_snapshot_dump() would operate on SnapshotInfoList but
643          * we convert to the block layer's native QEMUSnapshotInfo for now.
644          */
645         for (elem = info->snapshots; elem; elem = elem->next) {
646             QEMUSnapshotInfo sn = {
647                 .vm_state_size = elem->value->vm_state_size,
648                 .date_sec = elem->value->date_sec,
649                 .date_nsec = elem->value->date_nsec,
650                 .vm_clock_nsec = elem->value->vm_clock_sec * 1000000000ULL +
651                                  elem->value->vm_clock_nsec,
652             };
653 
654             pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id);
655             pstrcpy(sn.name, sizeof(sn.name), elem->value->name);
656             bdrv_snapshot_dump(func_fprintf, f, &sn);
657             func_fprintf(f, "\n");
658         }
659     }
660 
661     if (info->has_format_specific) {
662         func_fprintf(f, "Format specific information:\n");
663         bdrv_image_info_specific_dump(func_fprintf, f, info->format_specific);
664     }
665 }
666