xref: /openbmc/qemu/qemu-img.c (revision f1f7e4bf)
1 /*
2  * QEMU disk image utility
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 #include "qapi-visit.h"
25 #include "qapi/qmp-output-visitor.h"
26 #include "qapi/qmp/qerror.h"
27 #include "qapi/qmp/qjson.h"
28 #include "qemu-common.h"
29 #include "qemu/option.h"
30 #include "qemu/error-report.h"
31 #include "qemu/osdep.h"
32 #include "sysemu/sysemu.h"
33 #include "sysemu/block-backend.h"
34 #include "block/block_int.h"
35 #include "block/blockjob.h"
36 #include "block/qapi.h"
37 #include <getopt.h>
38 
39 #define QEMU_IMG_VERSION "qemu-img version " QEMU_VERSION QEMU_PKGVERSION \
40                           ", Copyright (c) 2004-2008 Fabrice Bellard\n"
41 
42 typedef struct img_cmd_t {
43     const char *name;
44     int (*handler)(int argc, char **argv);
45 } img_cmd_t;
46 
47 enum {
48     OPTION_OUTPUT = 256,
49     OPTION_BACKING_CHAIN = 257,
50 };
51 
52 typedef enum OutputFormat {
53     OFORMAT_JSON,
54     OFORMAT_HUMAN,
55 } OutputFormat;
56 
57 /* Default to cache=writeback as data integrity is not important for qemu-tcg. */
58 #define BDRV_O_FLAGS BDRV_O_CACHE_WB
59 #define BDRV_DEFAULT_CACHE "writeback"
60 
61 static void format_print(void *opaque, const char *name)
62 {
63     printf(" %s", name);
64 }
65 
66 static void QEMU_NORETURN GCC_FMT_ATTR(1, 2) error_exit(const char *fmt, ...)
67 {
68     va_list ap;
69 
70     error_printf("qemu-img: ");
71 
72     va_start(ap, fmt);
73     error_vprintf(fmt, ap);
74     va_end(ap);
75 
76     error_printf("\nTry 'qemu-img --help' for more information\n");
77     exit(EXIT_FAILURE);
78 }
79 
80 /* Please keep in synch with qemu-img.texi */
81 static void QEMU_NORETURN help(void)
82 {
83     const char *help_msg =
84            QEMU_IMG_VERSION
85            "usage: qemu-img command [command options]\n"
86            "QEMU disk image utility\n"
87            "\n"
88            "Command syntax:\n"
89 #define DEF(option, callback, arg_string)        \
90            "  " arg_string "\n"
91 #include "qemu-img-cmds.h"
92 #undef DEF
93 #undef GEN_DOCS
94            "\n"
95            "Command parameters:\n"
96            "  'filename' is a disk image filename\n"
97            "  'fmt' is the disk image format. It is guessed automatically in most cases\n"
98            "  'cache' is the cache mode used to write the output disk image, the valid\n"
99            "    options are: 'none', 'writeback' (default, except for convert), 'writethrough',\n"
100            "    'directsync' and 'unsafe' (default for convert)\n"
101            "  'src_cache' is the cache mode used to read input disk images, the valid\n"
102            "    options are the same as for the 'cache' option\n"
103            "  'size' is the disk image size in bytes. Optional suffixes\n"
104            "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M),\n"
105            "    'T' (terabyte, 1024G), 'P' (petabyte, 1024T) and 'E' (exabyte, 1024P)  are\n"
106            "    supported. 'b' is ignored.\n"
107            "  'output_filename' is the destination disk image filename\n"
108            "  'output_fmt' is the destination format\n"
109            "  'options' is a comma separated list of format specific options in a\n"
110            "    name=value format. Use -o ? for an overview of the options supported by the\n"
111            "    used format\n"
112            "  'snapshot_param' is param used for internal snapshot, format\n"
113            "    is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
114            "    '[ID_OR_NAME]'\n"
115            "  'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n"
116            "    instead\n"
117            "  '-c' indicates that target image must be compressed (qcow format only)\n"
118            "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"
119            "       match exactly. The image doesn't need a working backing file before\n"
120            "       rebasing in this case (useful for renaming the backing file)\n"
121            "  '-h' with or without a command shows this help and lists the supported formats\n"
122            "  '-p' show progress of command (only certain commands)\n"
123            "  '-q' use Quiet mode - do not print any output (except errors)\n"
124            "  '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
125            "       contain only zeros for qemu-img to create a sparse image during\n"
126            "       conversion. If the number of bytes is 0, the source will not be scanned for\n"
127            "       unallocated or zero sectors, and the destination image will always be\n"
128            "       fully allocated\n"
129            "  '--output' takes the format in which the output must be done (human or json)\n"
130            "  '-n' skips the target volume creation (useful if the volume is created\n"
131            "       prior to running qemu-img)\n"
132            "\n"
133            "Parameters to check subcommand:\n"
134            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
135            "       '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"
136            "       kinds of errors, with a higher risk of choosing the wrong fix or\n"
137            "       hiding corruption that has already occurred.\n"
138            "\n"
139            "Parameters to snapshot subcommand:\n"
140            "  'snapshot' is the name of the snapshot to create, apply or delete\n"
141            "  '-a' applies a snapshot (revert disk to saved state)\n"
142            "  '-c' creates a snapshot\n"
143            "  '-d' deletes a snapshot\n"
144            "  '-l' lists all snapshots in the given image\n"
145            "\n"
146            "Parameters to compare subcommand:\n"
147            "  '-f' first image format\n"
148            "  '-F' second image format\n"
149            "  '-s' run in Strict mode - fail on different image size or sector allocation\n";
150 
151     printf("%s\nSupported formats:", help_msg);
152     bdrv_iterate_format(format_print, NULL);
153     printf("\n");
154     exit(EXIT_SUCCESS);
155 }
156 
157 static int GCC_FMT_ATTR(2, 3) qprintf(bool quiet, const char *fmt, ...)
158 {
159     int ret = 0;
160     if (!quiet) {
161         va_list args;
162         va_start(args, fmt);
163         ret = vprintf(fmt, args);
164         va_end(args);
165     }
166     return ret;
167 }
168 
169 
170 static int print_block_option_help(const char *filename, const char *fmt)
171 {
172     BlockDriver *drv, *proto_drv;
173     QemuOptsList *create_opts = NULL;
174     Error *local_err = NULL;
175 
176     /* Find driver and parse its options */
177     drv = bdrv_find_format(fmt);
178     if (!drv) {
179         error_report("Unknown file format '%s'", fmt);
180         return 1;
181     }
182 
183     create_opts = qemu_opts_append(create_opts, drv->create_opts);
184     if (filename) {
185         proto_drv = bdrv_find_protocol(filename, true, &local_err);
186         if (!proto_drv) {
187             error_report_err(local_err);
188             qemu_opts_free(create_opts);
189             return 1;
190         }
191         create_opts = qemu_opts_append(create_opts, proto_drv->create_opts);
192     }
193 
194     qemu_opts_print_help(create_opts);
195     qemu_opts_free(create_opts);
196     return 0;
197 }
198 
199 static BlockBackend *img_open(const char *id, const char *filename,
200                               const char *fmt, int flags,
201                               bool require_io, bool quiet)
202 {
203     BlockBackend *blk;
204     BlockDriverState *bs;
205     char password[256];
206     Error *local_err = NULL;
207     QDict *options = NULL;
208 
209     if (fmt) {
210         options = qdict_new();
211         qdict_put(options, "driver", qstring_from_str(fmt));
212     }
213 
214     blk = blk_new_open(id, filename, NULL, options, flags, &local_err);
215     if (!blk) {
216         error_report("Could not open '%s': %s", filename,
217                      error_get_pretty(local_err));
218         error_free(local_err);
219         goto fail;
220     }
221 
222     bs = blk_bs(blk);
223     if (bdrv_is_encrypted(bs) && require_io) {
224         qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);
225         if (qemu_read_password(password, sizeof(password)) < 0) {
226             error_report("No password given");
227             goto fail;
228         }
229         if (bdrv_set_key(bs, password) < 0) {
230             error_report("invalid password");
231             goto fail;
232         }
233     }
234     return blk;
235 fail:
236     blk_unref(blk);
237     return NULL;
238 }
239 
240 static int add_old_style_options(const char *fmt, QemuOpts *opts,
241                                  const char *base_filename,
242                                  const char *base_fmt)
243 {
244     Error *err = NULL;
245 
246     if (base_filename) {
247         qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, &err);
248         if (err) {
249             error_report("Backing file not supported for file format '%s'",
250                          fmt);
251             error_free(err);
252             return -1;
253         }
254     }
255     if (base_fmt) {
256         qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, &err);
257         if (err) {
258             error_report("Backing file format not supported for file "
259                          "format '%s'", fmt);
260             error_free(err);
261             return -1;
262         }
263     }
264     return 0;
265 }
266 
267 static int img_create(int argc, char **argv)
268 {
269     int c;
270     uint64_t img_size = -1;
271     const char *fmt = "raw";
272     const char *base_fmt = NULL;
273     const char *filename;
274     const char *base_filename = NULL;
275     char *options = NULL;
276     Error *local_err = NULL;
277     bool quiet = false;
278 
279     for(;;) {
280         c = getopt(argc, argv, "F:b:f:he6o:q");
281         if (c == -1) {
282             break;
283         }
284         switch(c) {
285         case '?':
286         case 'h':
287             help();
288             break;
289         case 'F':
290             base_fmt = optarg;
291             break;
292         case 'b':
293             base_filename = optarg;
294             break;
295         case 'f':
296             fmt = optarg;
297             break;
298         case 'e':
299             error_report("option -e is deprecated, please use \'-o "
300                   "encryption\' instead!");
301             goto fail;
302         case '6':
303             error_report("option -6 is deprecated, please use \'-o "
304                   "compat6\' instead!");
305             goto fail;
306         case 'o':
307             if (!is_valid_option_list(optarg)) {
308                 error_report("Invalid option list: %s", optarg);
309                 goto fail;
310             }
311             if (!options) {
312                 options = g_strdup(optarg);
313             } else {
314                 char *old_options = options;
315                 options = g_strdup_printf("%s,%s", options, optarg);
316                 g_free(old_options);
317             }
318             break;
319         case 'q':
320             quiet = true;
321             break;
322         }
323     }
324 
325     /* Get the filename */
326     filename = (optind < argc) ? argv[optind] : NULL;
327     if (options && has_help_option(options)) {
328         g_free(options);
329         return print_block_option_help(filename, fmt);
330     }
331 
332     if (optind >= argc) {
333         error_exit("Expecting image file name");
334     }
335     optind++;
336 
337     /* Get image size, if specified */
338     if (optind < argc) {
339         int64_t sval;
340         char *end;
341         sval = qemu_strtosz_suffix(argv[optind++], &end,
342                                    QEMU_STRTOSZ_DEFSUFFIX_B);
343         if (sval < 0 || *end) {
344             if (sval == -ERANGE) {
345                 error_report("Image size must be less than 8 EiB!");
346             } else {
347                 error_report("Invalid image size specified! You may use k, M, "
348                       "G, T, P or E suffixes for ");
349                 error_report("kilobytes, megabytes, gigabytes, terabytes, "
350                              "petabytes and exabytes.");
351             }
352             goto fail;
353         }
354         img_size = (uint64_t)sval;
355     }
356     if (optind != argc) {
357         error_exit("Unexpected argument: %s", argv[optind]);
358     }
359 
360     bdrv_img_create(filename, fmt, base_filename, base_fmt,
361                     options, img_size, BDRV_O_FLAGS, &local_err, quiet);
362     if (local_err) {
363         error_report("%s: %s", filename, error_get_pretty(local_err));
364         error_free(local_err);
365         goto fail;
366     }
367 
368     g_free(options);
369     return 0;
370 
371 fail:
372     g_free(options);
373     return 1;
374 }
375 
376 static void dump_json_image_check(ImageCheck *check, bool quiet)
377 {
378     Error *local_err = NULL;
379     QString *str;
380     QmpOutputVisitor *ov = qmp_output_visitor_new();
381     QObject *obj;
382     visit_type_ImageCheck(qmp_output_get_visitor(ov),
383                           &check, NULL, &local_err);
384     obj = qmp_output_get_qobject(ov);
385     str = qobject_to_json_pretty(obj);
386     assert(str != NULL);
387     qprintf(quiet, "%s\n", qstring_get_str(str));
388     qobject_decref(obj);
389     qmp_output_visitor_cleanup(ov);
390     QDECREF(str);
391 }
392 
393 static void dump_human_image_check(ImageCheck *check, bool quiet)
394 {
395     if (!(check->corruptions || check->leaks || check->check_errors)) {
396         qprintf(quiet, "No errors were found on the image.\n");
397     } else {
398         if (check->corruptions) {
399             qprintf(quiet, "\n%" PRId64 " errors were found on the image.\n"
400                     "Data may be corrupted, or further writes to the image "
401                     "may corrupt it.\n",
402                     check->corruptions);
403         }
404 
405         if (check->leaks) {
406             qprintf(quiet,
407                     "\n%" PRId64 " leaked clusters were found on the image.\n"
408                     "This means waste of disk space, but no harm to data.\n",
409                     check->leaks);
410         }
411 
412         if (check->check_errors) {
413             qprintf(quiet,
414                     "\n%" PRId64
415                     " internal errors have occurred during the check.\n",
416                     check->check_errors);
417         }
418     }
419 
420     if (check->total_clusters != 0 && check->allocated_clusters != 0) {
421         qprintf(quiet, "%" PRId64 "/%" PRId64 " = %0.2f%% allocated, "
422                 "%0.2f%% fragmented, %0.2f%% compressed clusters\n",
423                 check->allocated_clusters, check->total_clusters,
424                 check->allocated_clusters * 100.0 / check->total_clusters,
425                 check->fragmented_clusters * 100.0 / check->allocated_clusters,
426                 check->compressed_clusters * 100.0 /
427                 check->allocated_clusters);
428     }
429 
430     if (check->image_end_offset) {
431         qprintf(quiet,
432                 "Image end offset: %" PRId64 "\n", check->image_end_offset);
433     }
434 }
435 
436 static int collect_image_check(BlockDriverState *bs,
437                    ImageCheck *check,
438                    const char *filename,
439                    const char *fmt,
440                    int fix)
441 {
442     int ret;
443     BdrvCheckResult result;
444 
445     ret = bdrv_check(bs, &result, fix);
446     if (ret < 0) {
447         return ret;
448     }
449 
450     check->filename                 = g_strdup(filename);
451     check->format                   = g_strdup(bdrv_get_format_name(bs));
452     check->check_errors             = result.check_errors;
453     check->corruptions              = result.corruptions;
454     check->has_corruptions          = result.corruptions != 0;
455     check->leaks                    = result.leaks;
456     check->has_leaks                = result.leaks != 0;
457     check->corruptions_fixed        = result.corruptions_fixed;
458     check->has_corruptions_fixed    = result.corruptions != 0;
459     check->leaks_fixed              = result.leaks_fixed;
460     check->has_leaks_fixed          = result.leaks != 0;
461     check->image_end_offset         = result.image_end_offset;
462     check->has_image_end_offset     = result.image_end_offset != 0;
463     check->total_clusters           = result.bfi.total_clusters;
464     check->has_total_clusters       = result.bfi.total_clusters != 0;
465     check->allocated_clusters       = result.bfi.allocated_clusters;
466     check->has_allocated_clusters   = result.bfi.allocated_clusters != 0;
467     check->fragmented_clusters      = result.bfi.fragmented_clusters;
468     check->has_fragmented_clusters  = result.bfi.fragmented_clusters != 0;
469     check->compressed_clusters      = result.bfi.compressed_clusters;
470     check->has_compressed_clusters  = result.bfi.compressed_clusters != 0;
471 
472     return 0;
473 }
474 
475 /*
476  * Checks an image for consistency. Exit codes:
477  *
478  *  0 - Check completed, image is good
479  *  1 - Check not completed because of internal errors
480  *  2 - Check completed, image is corrupted
481  *  3 - Check completed, image has leaked clusters, but is good otherwise
482  * 63 - Checks are not supported by the image format
483  */
484 static int img_check(int argc, char **argv)
485 {
486     int c, ret;
487     OutputFormat output_format = OFORMAT_HUMAN;
488     const char *filename, *fmt, *output, *cache;
489     BlockBackend *blk;
490     BlockDriverState *bs;
491     int fix = 0;
492     int flags = BDRV_O_FLAGS | BDRV_O_CHECK;
493     ImageCheck *check;
494     bool quiet = false;
495 
496     fmt = NULL;
497     output = NULL;
498     cache = BDRV_DEFAULT_CACHE;
499     for(;;) {
500         int option_index = 0;
501         static const struct option long_options[] = {
502             {"help", no_argument, 0, 'h'},
503             {"format", required_argument, 0, 'f'},
504             {"repair", required_argument, 0, 'r'},
505             {"output", required_argument, 0, OPTION_OUTPUT},
506             {0, 0, 0, 0}
507         };
508         c = getopt_long(argc, argv, "hf:r:T:q",
509                         long_options, &option_index);
510         if (c == -1) {
511             break;
512         }
513         switch(c) {
514         case '?':
515         case 'h':
516             help();
517             break;
518         case 'f':
519             fmt = optarg;
520             break;
521         case 'r':
522             flags |= BDRV_O_RDWR;
523 
524             if (!strcmp(optarg, "leaks")) {
525                 fix = BDRV_FIX_LEAKS;
526             } else if (!strcmp(optarg, "all")) {
527                 fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS;
528             } else {
529                 error_exit("Unknown option value for -r "
530                            "(expecting 'leaks' or 'all'): %s", optarg);
531             }
532             break;
533         case OPTION_OUTPUT:
534             output = optarg;
535             break;
536         case 'T':
537             cache = optarg;
538             break;
539         case 'q':
540             quiet = true;
541             break;
542         }
543     }
544     if (optind != argc - 1) {
545         error_exit("Expecting one image file name");
546     }
547     filename = argv[optind++];
548 
549     if (output && !strcmp(output, "json")) {
550         output_format = OFORMAT_JSON;
551     } else if (output && !strcmp(output, "human")) {
552         output_format = OFORMAT_HUMAN;
553     } else if (output) {
554         error_report("--output must be used with human or json as argument.");
555         return 1;
556     }
557 
558     ret = bdrv_parse_cache_flags(cache, &flags);
559     if (ret < 0) {
560         error_report("Invalid source cache option: %s", cache);
561         return 1;
562     }
563 
564     blk = img_open("image", filename, fmt, flags, true, quiet);
565     if (!blk) {
566         return 1;
567     }
568     bs = blk_bs(blk);
569 
570     check = g_new0(ImageCheck, 1);
571     ret = collect_image_check(bs, check, filename, fmt, fix);
572 
573     if (ret == -ENOTSUP) {
574         error_report("This image format does not support checks");
575         ret = 63;
576         goto fail;
577     }
578 
579     if (check->corruptions_fixed || check->leaks_fixed) {
580         int corruptions_fixed, leaks_fixed;
581 
582         leaks_fixed         = check->leaks_fixed;
583         corruptions_fixed   = check->corruptions_fixed;
584 
585         if (output_format == OFORMAT_HUMAN) {
586             qprintf(quiet,
587                     "The following inconsistencies were found and repaired:\n\n"
588                     "    %" PRId64 " leaked clusters\n"
589                     "    %" PRId64 " corruptions\n\n"
590                     "Double checking the fixed image now...\n",
591                     check->leaks_fixed,
592                     check->corruptions_fixed);
593         }
594 
595         ret = collect_image_check(bs, check, filename, fmt, 0);
596 
597         check->leaks_fixed          = leaks_fixed;
598         check->corruptions_fixed    = corruptions_fixed;
599     }
600 
601     if (!ret) {
602         switch (output_format) {
603         case OFORMAT_HUMAN:
604             dump_human_image_check(check, quiet);
605             break;
606         case OFORMAT_JSON:
607             dump_json_image_check(check, quiet);
608             break;
609         }
610     }
611 
612     if (ret || check->check_errors) {
613         if (ret) {
614             error_report("Check failed: %s", strerror(-ret));
615         } else {
616             error_report("Check failed");
617         }
618         ret = 1;
619         goto fail;
620     }
621 
622     if (check->corruptions) {
623         ret = 2;
624     } else if (check->leaks) {
625         ret = 3;
626     } else {
627         ret = 0;
628     }
629 
630 fail:
631     qapi_free_ImageCheck(check);
632     blk_unref(blk);
633     return ret;
634 }
635 
636 typedef struct CommonBlockJobCBInfo {
637     BlockDriverState *bs;
638     Error **errp;
639 } CommonBlockJobCBInfo;
640 
641 static void common_block_job_cb(void *opaque, int ret)
642 {
643     CommonBlockJobCBInfo *cbi = opaque;
644 
645     if (ret < 0) {
646         error_setg_errno(cbi->errp, -ret, "Block job failed");
647     }
648 }
649 
650 static void run_block_job(BlockJob *job, Error **errp)
651 {
652     AioContext *aio_context = bdrv_get_aio_context(job->bs);
653 
654     do {
655         aio_poll(aio_context, true);
656         qemu_progress_print(job->len ?
657                             ((float)job->offset / job->len * 100.f) : 0.0f, 0);
658     } while (!job->ready);
659 
660     block_job_complete_sync(job, errp);
661 
662     /* A block job may finish instantaneously without publishing any progress,
663      * so just signal completion here */
664     qemu_progress_print(100.f, 0);
665 }
666 
667 static int img_commit(int argc, char **argv)
668 {
669     int c, ret, flags;
670     const char *filename, *fmt, *cache, *base;
671     BlockBackend *blk;
672     BlockDriverState *bs, *base_bs;
673     bool progress = false, quiet = false, drop = false;
674     Error *local_err = NULL;
675     CommonBlockJobCBInfo cbi;
676 
677     fmt = NULL;
678     cache = BDRV_DEFAULT_CACHE;
679     base = NULL;
680     for(;;) {
681         c = getopt(argc, argv, "f:ht:b:dpq");
682         if (c == -1) {
683             break;
684         }
685         switch(c) {
686         case '?':
687         case 'h':
688             help();
689             break;
690         case 'f':
691             fmt = optarg;
692             break;
693         case 't':
694             cache = optarg;
695             break;
696         case 'b':
697             base = optarg;
698             /* -b implies -d */
699             drop = true;
700             break;
701         case 'd':
702             drop = true;
703             break;
704         case 'p':
705             progress = true;
706             break;
707         case 'q':
708             quiet = true;
709             break;
710         }
711     }
712 
713     /* Progress is not shown in Quiet mode */
714     if (quiet) {
715         progress = false;
716     }
717 
718     if (optind != argc - 1) {
719         error_exit("Expecting one image file name");
720     }
721     filename = argv[optind++];
722 
723     flags = BDRV_O_RDWR | BDRV_O_UNMAP;
724     ret = bdrv_parse_cache_flags(cache, &flags);
725     if (ret < 0) {
726         error_report("Invalid cache option: %s", cache);
727         return 1;
728     }
729 
730     blk = img_open("image", filename, fmt, flags, true, quiet);
731     if (!blk) {
732         return 1;
733     }
734     bs = blk_bs(blk);
735 
736     qemu_progress_init(progress, 1.f);
737     qemu_progress_print(0.f, 100);
738 
739     if (base) {
740         base_bs = bdrv_find_backing_image(bs, base);
741         if (!base_bs) {
742             error_setg(&local_err, QERR_BASE_NOT_FOUND, base);
743             goto done;
744         }
745     } else {
746         /* This is different from QMP, which by default uses the deepest file in
747          * the backing chain (i.e., the very base); however, the traditional
748          * behavior of qemu-img commit is using the immediate backing file. */
749         base_bs = backing_bs(bs);
750         if (!base_bs) {
751             error_setg(&local_err, "Image does not have a backing file");
752             goto done;
753         }
754     }
755 
756     cbi = (CommonBlockJobCBInfo){
757         .errp = &local_err,
758         .bs   = bs,
759     };
760 
761     commit_active_start(bs, base_bs, 0, BLOCKDEV_ON_ERROR_REPORT,
762                         common_block_job_cb, &cbi, &local_err);
763     if (local_err) {
764         goto done;
765     }
766 
767     /* When the block job completes, the BlockBackend reference will point to
768      * the old backing file. In order to avoid that the top image is already
769      * deleted, so we can still empty it afterwards, increment the reference
770      * counter here preemptively. */
771     if (!drop) {
772         bdrv_ref(bs);
773     }
774 
775     run_block_job(bs->job, &local_err);
776     if (local_err) {
777         goto unref_backing;
778     }
779 
780     if (!drop && bs->drv->bdrv_make_empty) {
781         ret = bs->drv->bdrv_make_empty(bs);
782         if (ret) {
783             error_setg_errno(&local_err, -ret, "Could not empty %s",
784                              filename);
785             goto unref_backing;
786         }
787     }
788 
789 unref_backing:
790     if (!drop) {
791         bdrv_unref(bs);
792     }
793 
794 done:
795     qemu_progress_end();
796 
797     blk_unref(blk);
798 
799     if (local_err) {
800         error_report_err(local_err);
801         return 1;
802     }
803 
804     qprintf(quiet, "Image committed.\n");
805     return 0;
806 }
807 
808 /*
809  * Returns true iff the first sector pointed to by 'buf' contains at least
810  * a non-NUL byte.
811  *
812  * 'pnum' is set to the number of sectors (including and immediately following
813  * the first one) that are known to be in the same allocated/unallocated state.
814  */
815 static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)
816 {
817     bool is_zero;
818     int i;
819 
820     if (n <= 0) {
821         *pnum = 0;
822         return 0;
823     }
824     is_zero = buffer_is_zero(buf, 512);
825     for(i = 1; i < n; i++) {
826         buf += 512;
827         if (is_zero != buffer_is_zero(buf, 512)) {
828             break;
829         }
830     }
831     *pnum = i;
832     return !is_zero;
833 }
834 
835 /*
836  * Like is_allocated_sectors, but if the buffer starts with a used sector,
837  * up to 'min' consecutive sectors containing zeros are ignored. This avoids
838  * breaking up write requests for only small sparse areas.
839  */
840 static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,
841     int min)
842 {
843     int ret;
844     int num_checked, num_used;
845 
846     if (n < min) {
847         min = n;
848     }
849 
850     ret = is_allocated_sectors(buf, n, pnum);
851     if (!ret) {
852         return ret;
853     }
854 
855     num_used = *pnum;
856     buf += BDRV_SECTOR_SIZE * *pnum;
857     n -= *pnum;
858     num_checked = num_used;
859 
860     while (n > 0) {
861         ret = is_allocated_sectors(buf, n, pnum);
862 
863         buf += BDRV_SECTOR_SIZE * *pnum;
864         n -= *pnum;
865         num_checked += *pnum;
866         if (ret) {
867             num_used = num_checked;
868         } else if (*pnum >= min) {
869             break;
870         }
871     }
872 
873     *pnum = num_used;
874     return 1;
875 }
876 
877 /*
878  * Compares two buffers sector by sector. Returns 0 if the first sector of both
879  * buffers matches, non-zero otherwise.
880  *
881  * pnum is set to the number of sectors (including and immediately following
882  * the first one) that are known to have the same comparison result
883  */
884 static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
885     int *pnum)
886 {
887     bool res;
888     int i;
889 
890     if (n <= 0) {
891         *pnum = 0;
892         return 0;
893     }
894 
895     res = !!memcmp(buf1, buf2, 512);
896     for(i = 1; i < n; i++) {
897         buf1 += 512;
898         buf2 += 512;
899 
900         if (!!memcmp(buf1, buf2, 512) != res) {
901             break;
902         }
903     }
904 
905     *pnum = i;
906     return res;
907 }
908 
909 #define IO_BUF_SIZE (2 * 1024 * 1024)
910 
911 static int64_t sectors_to_bytes(int64_t sectors)
912 {
913     return sectors << BDRV_SECTOR_BITS;
914 }
915 
916 static int64_t sectors_to_process(int64_t total, int64_t from)
917 {
918     return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);
919 }
920 
921 /*
922  * Check if passed sectors are empty (not allocated or contain only 0 bytes)
923  *
924  * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero
925  * data and negative value on error.
926  *
927  * @param blk:  BlockBackend for the image
928  * @param sect_num: Number of first sector to check
929  * @param sect_count: Number of sectors to check
930  * @param filename: Name of disk file we are checking (logging purpose)
931  * @param buffer: Allocated buffer for storing read data
932  * @param quiet: Flag for quiet mode
933  */
934 static int check_empty_sectors(BlockBackend *blk, int64_t sect_num,
935                                int sect_count, const char *filename,
936                                uint8_t *buffer, bool quiet)
937 {
938     int pnum, ret = 0;
939     ret = blk_read(blk, sect_num, buffer, sect_count);
940     if (ret < 0) {
941         error_report("Error while reading offset %" PRId64 " of %s: %s",
942                      sectors_to_bytes(sect_num), filename, strerror(-ret));
943         return ret;
944     }
945     ret = is_allocated_sectors(buffer, sect_count, &pnum);
946     if (ret || pnum != sect_count) {
947         qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
948                 sectors_to_bytes(ret ? sect_num : sect_num + pnum));
949         return 1;
950     }
951 
952     return 0;
953 }
954 
955 /*
956  * Compares two images. Exit codes:
957  *
958  * 0 - Images are identical
959  * 1 - Images differ
960  * >1 - Error occurred
961  */
962 static int img_compare(int argc, char **argv)
963 {
964     const char *fmt1 = NULL, *fmt2 = NULL, *cache, *filename1, *filename2;
965     BlockBackend *blk1, *blk2;
966     BlockDriverState *bs1, *bs2;
967     int64_t total_sectors1, total_sectors2;
968     uint8_t *buf1 = NULL, *buf2 = NULL;
969     int pnum1, pnum2;
970     int allocated1, allocated2;
971     int ret = 0; /* return value - 0 Ident, 1 Different, >1 Error */
972     bool progress = false, quiet = false, strict = false;
973     int flags;
974     int64_t total_sectors;
975     int64_t sector_num = 0;
976     int64_t nb_sectors;
977     int c, pnum;
978     uint64_t progress_base;
979 
980     cache = BDRV_DEFAULT_CACHE;
981     for (;;) {
982         c = getopt(argc, argv, "hf:F:T:pqs");
983         if (c == -1) {
984             break;
985         }
986         switch (c) {
987         case '?':
988         case 'h':
989             help();
990             break;
991         case 'f':
992             fmt1 = optarg;
993             break;
994         case 'F':
995             fmt2 = optarg;
996             break;
997         case 'T':
998             cache = optarg;
999             break;
1000         case 'p':
1001             progress = true;
1002             break;
1003         case 'q':
1004             quiet = true;
1005             break;
1006         case 's':
1007             strict = true;
1008             break;
1009         }
1010     }
1011 
1012     /* Progress is not shown in Quiet mode */
1013     if (quiet) {
1014         progress = false;
1015     }
1016 
1017 
1018     if (optind != argc - 2) {
1019         error_exit("Expecting two image file names");
1020     }
1021     filename1 = argv[optind++];
1022     filename2 = argv[optind++];
1023 
1024     /* Initialize before goto out */
1025     qemu_progress_init(progress, 2.0);
1026 
1027     flags = BDRV_O_FLAGS;
1028     ret = bdrv_parse_cache_flags(cache, &flags);
1029     if (ret < 0) {
1030         error_report("Invalid source cache option: %s", cache);
1031         ret = 2;
1032         goto out3;
1033     }
1034 
1035     blk1 = img_open("image_1", filename1, fmt1, flags, true, quiet);
1036     if (!blk1) {
1037         ret = 2;
1038         goto out3;
1039     }
1040     bs1 = blk_bs(blk1);
1041 
1042     blk2 = img_open("image_2", filename2, fmt2, flags, true, quiet);
1043     if (!blk2) {
1044         ret = 2;
1045         goto out2;
1046     }
1047     bs2 = blk_bs(blk2);
1048 
1049     buf1 = blk_blockalign(blk1, IO_BUF_SIZE);
1050     buf2 = blk_blockalign(blk2, IO_BUF_SIZE);
1051     total_sectors1 = blk_nb_sectors(blk1);
1052     if (total_sectors1 < 0) {
1053         error_report("Can't get size of %s: %s",
1054                      filename1, strerror(-total_sectors1));
1055         ret = 4;
1056         goto out;
1057     }
1058     total_sectors2 = blk_nb_sectors(blk2);
1059     if (total_sectors2 < 0) {
1060         error_report("Can't get size of %s: %s",
1061                      filename2, strerror(-total_sectors2));
1062         ret = 4;
1063         goto out;
1064     }
1065     total_sectors = MIN(total_sectors1, total_sectors2);
1066     progress_base = MAX(total_sectors1, total_sectors2);
1067 
1068     qemu_progress_print(0, 100);
1069 
1070     if (strict && total_sectors1 != total_sectors2) {
1071         ret = 1;
1072         qprintf(quiet, "Strict mode: Image size mismatch!\n");
1073         goto out;
1074     }
1075 
1076     for (;;) {
1077         nb_sectors = sectors_to_process(total_sectors, sector_num);
1078         if (nb_sectors <= 0) {
1079             break;
1080         }
1081         allocated1 = bdrv_is_allocated_above(bs1, NULL, sector_num, nb_sectors,
1082                                              &pnum1);
1083         if (allocated1 < 0) {
1084             ret = 3;
1085             error_report("Sector allocation test failed for %s", filename1);
1086             goto out;
1087         }
1088 
1089         allocated2 = bdrv_is_allocated_above(bs2, NULL, sector_num, nb_sectors,
1090                                              &pnum2);
1091         if (allocated2 < 0) {
1092             ret = 3;
1093             error_report("Sector allocation test failed for %s", filename2);
1094             goto out;
1095         }
1096         nb_sectors = MIN(pnum1, pnum2);
1097 
1098         if (allocated1 == allocated2) {
1099             if (allocated1) {
1100                 ret = blk_read(blk1, sector_num, buf1, nb_sectors);
1101                 if (ret < 0) {
1102                     error_report("Error while reading offset %" PRId64 " of %s:"
1103                                  " %s", sectors_to_bytes(sector_num), filename1,
1104                                  strerror(-ret));
1105                     ret = 4;
1106                     goto out;
1107                 }
1108                 ret = blk_read(blk2, sector_num, buf2, nb_sectors);
1109                 if (ret < 0) {
1110                     error_report("Error while reading offset %" PRId64
1111                                  " of %s: %s", sectors_to_bytes(sector_num),
1112                                  filename2, strerror(-ret));
1113                     ret = 4;
1114                     goto out;
1115                 }
1116                 ret = compare_sectors(buf1, buf2, nb_sectors, &pnum);
1117                 if (ret || pnum != nb_sectors) {
1118                     qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
1119                             sectors_to_bytes(
1120                                 ret ? sector_num : sector_num + pnum));
1121                     ret = 1;
1122                     goto out;
1123                 }
1124             }
1125         } else {
1126             if (strict) {
1127                 ret = 1;
1128                 qprintf(quiet, "Strict mode: Offset %" PRId64
1129                         " allocation mismatch!\n",
1130                         sectors_to_bytes(sector_num));
1131                 goto out;
1132             }
1133 
1134             if (allocated1) {
1135                 ret = check_empty_sectors(blk1, sector_num, nb_sectors,
1136                                           filename1, buf1, quiet);
1137             } else {
1138                 ret = check_empty_sectors(blk2, sector_num, nb_sectors,
1139                                           filename2, buf1, quiet);
1140             }
1141             if (ret) {
1142                 if (ret < 0) {
1143                     error_report("Error while reading offset %" PRId64 ": %s",
1144                                  sectors_to_bytes(sector_num), strerror(-ret));
1145                     ret = 4;
1146                 }
1147                 goto out;
1148             }
1149         }
1150         sector_num += nb_sectors;
1151         qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1152     }
1153 
1154     if (total_sectors1 != total_sectors2) {
1155         BlockBackend *blk_over;
1156         int64_t total_sectors_over;
1157         const char *filename_over;
1158 
1159         qprintf(quiet, "Warning: Image size mismatch!\n");
1160         if (total_sectors1 > total_sectors2) {
1161             total_sectors_over = total_sectors1;
1162             blk_over = blk1;
1163             filename_over = filename1;
1164         } else {
1165             total_sectors_over = total_sectors2;
1166             blk_over = blk2;
1167             filename_over = filename2;
1168         }
1169 
1170         for (;;) {
1171             nb_sectors = sectors_to_process(total_sectors_over, sector_num);
1172             if (nb_sectors <= 0) {
1173                 break;
1174             }
1175             ret = bdrv_is_allocated_above(blk_bs(blk_over), NULL, sector_num,
1176                                           nb_sectors, &pnum);
1177             if (ret < 0) {
1178                 ret = 3;
1179                 error_report("Sector allocation test failed for %s",
1180                              filename_over);
1181                 goto out;
1182 
1183             }
1184             nb_sectors = pnum;
1185             if (ret) {
1186                 ret = check_empty_sectors(blk_over, sector_num, nb_sectors,
1187                                           filename_over, buf1, quiet);
1188                 if (ret) {
1189                     if (ret < 0) {
1190                         error_report("Error while reading offset %" PRId64
1191                                      " of %s: %s", sectors_to_bytes(sector_num),
1192                                      filename_over, strerror(-ret));
1193                         ret = 4;
1194                     }
1195                     goto out;
1196                 }
1197             }
1198             sector_num += nb_sectors;
1199             qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1200         }
1201     }
1202 
1203     qprintf(quiet, "Images are identical.\n");
1204     ret = 0;
1205 
1206 out:
1207     qemu_vfree(buf1);
1208     qemu_vfree(buf2);
1209     blk_unref(blk2);
1210 out2:
1211     blk_unref(blk1);
1212 out3:
1213     qemu_progress_end();
1214     return ret;
1215 }
1216 
1217 enum ImgConvertBlockStatus {
1218     BLK_DATA,
1219     BLK_ZERO,
1220     BLK_BACKING_FILE,
1221 };
1222 
1223 typedef struct ImgConvertState {
1224     BlockBackend **src;
1225     int64_t *src_sectors;
1226     int src_cur, src_num;
1227     int64_t src_cur_offset;
1228     int64_t total_sectors;
1229     int64_t allocated_sectors;
1230     enum ImgConvertBlockStatus status;
1231     int64_t sector_next_status;
1232     BlockBackend *target;
1233     bool has_zero_init;
1234     bool compressed;
1235     bool target_has_backing;
1236     int min_sparse;
1237     size_t cluster_sectors;
1238     size_t buf_sectors;
1239 } ImgConvertState;
1240 
1241 static void convert_select_part(ImgConvertState *s, int64_t sector_num)
1242 {
1243     assert(sector_num >= s->src_cur_offset);
1244     while (sector_num - s->src_cur_offset >= s->src_sectors[s->src_cur]) {
1245         s->src_cur_offset += s->src_sectors[s->src_cur];
1246         s->src_cur++;
1247         assert(s->src_cur < s->src_num);
1248     }
1249 }
1250 
1251 static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num)
1252 {
1253     int64_t ret;
1254     int n;
1255 
1256     convert_select_part(s, sector_num);
1257 
1258     assert(s->total_sectors > sector_num);
1259     n = MIN(s->total_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS);
1260 
1261     if (s->sector_next_status <= sector_num) {
1262         ret = bdrv_get_block_status(blk_bs(s->src[s->src_cur]),
1263                                     sector_num - s->src_cur_offset,
1264                                     n, &n);
1265         if (ret < 0) {
1266             return ret;
1267         }
1268 
1269         if (ret & BDRV_BLOCK_ZERO) {
1270             s->status = BLK_ZERO;
1271         } else if (ret & BDRV_BLOCK_DATA) {
1272             s->status = BLK_DATA;
1273         } else if (!s->target_has_backing) {
1274             /* Without a target backing file we must copy over the contents of
1275              * the backing file as well. */
1276             /* TODO Check block status of the backing file chain to avoid
1277              * needlessly reading zeroes and limiting the iteration to the
1278              * buffer size */
1279             s->status = BLK_DATA;
1280         } else {
1281             s->status = BLK_BACKING_FILE;
1282         }
1283 
1284         s->sector_next_status = sector_num + n;
1285     }
1286 
1287     n = MIN(n, s->sector_next_status - sector_num);
1288     if (s->status == BLK_DATA) {
1289         n = MIN(n, s->buf_sectors);
1290     }
1291 
1292     /* We need to write complete clusters for compressed images, so if an
1293      * unallocated area is shorter than that, we must consider the whole
1294      * cluster allocated. */
1295     if (s->compressed) {
1296         if (n < s->cluster_sectors) {
1297             n = MIN(s->cluster_sectors, s->total_sectors - sector_num);
1298             s->status = BLK_DATA;
1299         } else {
1300             n = QEMU_ALIGN_DOWN(n, s->cluster_sectors);
1301         }
1302     }
1303 
1304     return n;
1305 }
1306 
1307 static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors,
1308                         uint8_t *buf)
1309 {
1310     int n;
1311     int ret;
1312 
1313     if (s->status == BLK_ZERO || s->status == BLK_BACKING_FILE) {
1314         return 0;
1315     }
1316 
1317     assert(nb_sectors <= s->buf_sectors);
1318     while (nb_sectors > 0) {
1319         BlockBackend *blk;
1320         int64_t bs_sectors;
1321 
1322         /* In the case of compression with multiple source files, we can get a
1323          * nb_sectors that spreads into the next part. So we must be able to
1324          * read across multiple BDSes for one convert_read() call. */
1325         convert_select_part(s, sector_num);
1326         blk = s->src[s->src_cur];
1327         bs_sectors = s->src_sectors[s->src_cur];
1328 
1329         n = MIN(nb_sectors, bs_sectors - (sector_num - s->src_cur_offset));
1330         ret = blk_read(blk, sector_num - s->src_cur_offset, buf, n);
1331         if (ret < 0) {
1332             return ret;
1333         }
1334 
1335         sector_num += n;
1336         nb_sectors -= n;
1337         buf += n * BDRV_SECTOR_SIZE;
1338     }
1339 
1340     return 0;
1341 }
1342 
1343 static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors,
1344                          const uint8_t *buf)
1345 {
1346     int ret;
1347 
1348     while (nb_sectors > 0) {
1349         int n = nb_sectors;
1350 
1351         switch (s->status) {
1352         case BLK_BACKING_FILE:
1353             /* If we have a backing file, leave clusters unallocated that are
1354              * unallocated in the source image, so that the backing file is
1355              * visible at the respective offset. */
1356             assert(s->target_has_backing);
1357             break;
1358 
1359         case BLK_DATA:
1360             /* We must always write compressed clusters as a whole, so don't
1361              * try to find zeroed parts in the buffer. We can only save the
1362              * write if the buffer is completely zeroed and we're allowed to
1363              * keep the target sparse. */
1364             if (s->compressed) {
1365                 if (s->has_zero_init && s->min_sparse &&
1366                     buffer_is_zero(buf, n * BDRV_SECTOR_SIZE))
1367                 {
1368                     assert(!s->target_has_backing);
1369                     break;
1370                 }
1371 
1372                 ret = blk_write_compressed(s->target, sector_num, buf, n);
1373                 if (ret < 0) {
1374                     return ret;
1375                 }
1376                 break;
1377             }
1378 
1379             /* If there is real non-zero data or we're told to keep the target
1380              * fully allocated (-S 0), we must write it. Otherwise we can treat
1381              * it as zero sectors. */
1382             if (!s->min_sparse ||
1383                 is_allocated_sectors_min(buf, n, &n, s->min_sparse))
1384             {
1385                 ret = blk_write(s->target, sector_num, buf, n);
1386                 if (ret < 0) {
1387                     return ret;
1388                 }
1389                 break;
1390             }
1391             /* fall-through */
1392 
1393         case BLK_ZERO:
1394             if (s->has_zero_init) {
1395                 break;
1396             }
1397             ret = blk_write_zeroes(s->target, sector_num, n, 0);
1398             if (ret < 0) {
1399                 return ret;
1400             }
1401             break;
1402         }
1403 
1404         sector_num += n;
1405         nb_sectors -= n;
1406         buf += n * BDRV_SECTOR_SIZE;
1407     }
1408 
1409     return 0;
1410 }
1411 
1412 static int convert_do_copy(ImgConvertState *s)
1413 {
1414     uint8_t *buf = NULL;
1415     int64_t sector_num, allocated_done;
1416     int ret;
1417     int n;
1418 
1419     /* Check whether we have zero initialisation or can get it efficiently */
1420     s->has_zero_init = s->min_sparse && !s->target_has_backing
1421                      ? bdrv_has_zero_init(blk_bs(s->target))
1422                      : false;
1423 
1424     if (!s->has_zero_init && !s->target_has_backing &&
1425         bdrv_can_write_zeroes_with_unmap(blk_bs(s->target)))
1426     {
1427         ret = bdrv_make_zero(blk_bs(s->target), BDRV_REQ_MAY_UNMAP);
1428         if (ret == 0) {
1429             s->has_zero_init = true;
1430         }
1431     }
1432 
1433     /* Allocate buffer for copied data. For compressed images, only one cluster
1434      * can be copied at a time. */
1435     if (s->compressed) {
1436         if (s->cluster_sectors <= 0 || s->cluster_sectors > s->buf_sectors) {
1437             error_report("invalid cluster size");
1438             ret = -EINVAL;
1439             goto fail;
1440         }
1441         s->buf_sectors = s->cluster_sectors;
1442     }
1443     buf = blk_blockalign(s->target, s->buf_sectors * BDRV_SECTOR_SIZE);
1444 
1445     /* Calculate allocated sectors for progress */
1446     s->allocated_sectors = 0;
1447     sector_num = 0;
1448     while (sector_num < s->total_sectors) {
1449         n = convert_iteration_sectors(s, sector_num);
1450         if (n < 0) {
1451             ret = n;
1452             goto fail;
1453         }
1454         if (s->status == BLK_DATA) {
1455             s->allocated_sectors += n;
1456         }
1457         sector_num += n;
1458     }
1459 
1460     /* Do the copy */
1461     s->src_cur = 0;
1462     s->src_cur_offset = 0;
1463     s->sector_next_status = 0;
1464 
1465     sector_num = 0;
1466     allocated_done = 0;
1467 
1468     while (sector_num < s->total_sectors) {
1469         n = convert_iteration_sectors(s, sector_num);
1470         if (n < 0) {
1471             ret = n;
1472             goto fail;
1473         }
1474         if (s->status == BLK_DATA) {
1475             allocated_done += n;
1476             qemu_progress_print(100.0 * allocated_done / s->allocated_sectors,
1477                                 0);
1478         }
1479 
1480         ret = convert_read(s, sector_num, n, buf);
1481         if (ret < 0) {
1482             error_report("error while reading sector %" PRId64
1483                          ": %s", sector_num, strerror(-ret));
1484             goto fail;
1485         }
1486 
1487         ret = convert_write(s, sector_num, n, buf);
1488         if (ret < 0) {
1489             error_report("error while writing sector %" PRId64
1490                          ": %s", sector_num, strerror(-ret));
1491             goto fail;
1492         }
1493 
1494         sector_num += n;
1495     }
1496 
1497     if (s->compressed) {
1498         /* signal EOF to align */
1499         ret = blk_write_compressed(s->target, 0, NULL, 0);
1500         if (ret < 0) {
1501             goto fail;
1502         }
1503     }
1504 
1505     ret = 0;
1506 fail:
1507     qemu_vfree(buf);
1508     return ret;
1509 }
1510 
1511 static int img_convert(int argc, char **argv)
1512 {
1513     int c, bs_n, bs_i, compress, cluster_sectors, skip_create;
1514     int64_t ret = 0;
1515     int progress = 0, flags, src_flags;
1516     const char *fmt, *out_fmt, *cache, *src_cache, *out_baseimg, *out_filename;
1517     BlockDriver *drv, *proto_drv;
1518     BlockBackend **blk = NULL, *out_blk = NULL;
1519     BlockDriverState **bs = NULL, *out_bs = NULL;
1520     int64_t total_sectors;
1521     int64_t *bs_sectors = NULL;
1522     size_t bufsectors = IO_BUF_SIZE / BDRV_SECTOR_SIZE;
1523     BlockDriverInfo bdi;
1524     QemuOpts *opts = NULL;
1525     QemuOptsList *create_opts = NULL;
1526     const char *out_baseimg_param;
1527     char *options = NULL;
1528     const char *snapshot_name = NULL;
1529     int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */
1530     bool quiet = false;
1531     Error *local_err = NULL;
1532     QemuOpts *sn_opts = NULL;
1533     ImgConvertState state;
1534 
1535     fmt = NULL;
1536     out_fmt = "raw";
1537     cache = "unsafe";
1538     src_cache = BDRV_DEFAULT_CACHE;
1539     out_baseimg = NULL;
1540     compress = 0;
1541     skip_create = 0;
1542     for(;;) {
1543         c = getopt(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qn");
1544         if (c == -1) {
1545             break;
1546         }
1547         switch(c) {
1548         case '?':
1549         case 'h':
1550             help();
1551             break;
1552         case 'f':
1553             fmt = optarg;
1554             break;
1555         case 'O':
1556             out_fmt = optarg;
1557             break;
1558         case 'B':
1559             out_baseimg = optarg;
1560             break;
1561         case 'c':
1562             compress = 1;
1563             break;
1564         case 'e':
1565             error_report("option -e is deprecated, please use \'-o "
1566                   "encryption\' instead!");
1567             ret = -1;
1568             goto fail_getopt;
1569         case '6':
1570             error_report("option -6 is deprecated, please use \'-o "
1571                   "compat6\' instead!");
1572             ret = -1;
1573             goto fail_getopt;
1574         case 'o':
1575             if (!is_valid_option_list(optarg)) {
1576                 error_report("Invalid option list: %s", optarg);
1577                 ret = -1;
1578                 goto fail_getopt;
1579             }
1580             if (!options) {
1581                 options = g_strdup(optarg);
1582             } else {
1583                 char *old_options = options;
1584                 options = g_strdup_printf("%s,%s", options, optarg);
1585                 g_free(old_options);
1586             }
1587             break;
1588         case 's':
1589             snapshot_name = optarg;
1590             break;
1591         case 'l':
1592             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
1593                 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
1594                                                   optarg, false);
1595                 if (!sn_opts) {
1596                     error_report("Failed in parsing snapshot param '%s'",
1597                                  optarg);
1598                     ret = -1;
1599                     goto fail_getopt;
1600                 }
1601             } else {
1602                 snapshot_name = optarg;
1603             }
1604             break;
1605         case 'S':
1606         {
1607             int64_t sval;
1608             char *end;
1609             sval = qemu_strtosz_suffix(optarg, &end, QEMU_STRTOSZ_DEFSUFFIX_B);
1610             if (sval < 0 || *end) {
1611                 error_report("Invalid minimum zero buffer size for sparse output specified");
1612                 ret = -1;
1613                 goto fail_getopt;
1614             }
1615 
1616             min_sparse = sval / BDRV_SECTOR_SIZE;
1617             break;
1618         }
1619         case 'p':
1620             progress = 1;
1621             break;
1622         case 't':
1623             cache = optarg;
1624             break;
1625         case 'T':
1626             src_cache = optarg;
1627             break;
1628         case 'q':
1629             quiet = true;
1630             break;
1631         case 'n':
1632             skip_create = 1;
1633             break;
1634         }
1635     }
1636 
1637     /* Initialize before goto out */
1638     if (quiet) {
1639         progress = 0;
1640     }
1641     qemu_progress_init(progress, 1.0);
1642 
1643 
1644     bs_n = argc - optind - 1;
1645     out_filename = bs_n >= 1 ? argv[argc - 1] : NULL;
1646 
1647     if (options && has_help_option(options)) {
1648         ret = print_block_option_help(out_filename, out_fmt);
1649         goto out;
1650     }
1651 
1652     if (bs_n < 1) {
1653         error_exit("Must specify image file name");
1654     }
1655 
1656 
1657     if (bs_n > 1 && out_baseimg) {
1658         error_report("-B makes no sense when concatenating multiple input "
1659                      "images");
1660         ret = -1;
1661         goto out;
1662     }
1663 
1664     src_flags = BDRV_O_FLAGS;
1665     ret = bdrv_parse_cache_flags(src_cache, &src_flags);
1666     if (ret < 0) {
1667         error_report("Invalid source cache option: %s", src_cache);
1668         goto out;
1669     }
1670 
1671     qemu_progress_print(0, 100);
1672 
1673     blk = g_new0(BlockBackend *, bs_n);
1674     bs = g_new0(BlockDriverState *, bs_n);
1675     bs_sectors = g_new(int64_t, bs_n);
1676 
1677     total_sectors = 0;
1678     for (bs_i = 0; bs_i < bs_n; bs_i++) {
1679         char *id = bs_n > 1 ? g_strdup_printf("source_%d", bs_i)
1680                             : g_strdup("source");
1681         blk[bs_i] = img_open(id, argv[optind + bs_i], fmt, src_flags,
1682                              true, quiet);
1683         g_free(id);
1684         if (!blk[bs_i]) {
1685             ret = -1;
1686             goto out;
1687         }
1688         bs[bs_i] = blk_bs(blk[bs_i]);
1689         bs_sectors[bs_i] = blk_nb_sectors(blk[bs_i]);
1690         if (bs_sectors[bs_i] < 0) {
1691             error_report("Could not get size of %s: %s",
1692                          argv[optind + bs_i], strerror(-bs_sectors[bs_i]));
1693             ret = -1;
1694             goto out;
1695         }
1696         total_sectors += bs_sectors[bs_i];
1697     }
1698 
1699     if (sn_opts) {
1700         ret = bdrv_snapshot_load_tmp(bs[0],
1701                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1702                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1703                                      &local_err);
1704     } else if (snapshot_name != NULL) {
1705         if (bs_n > 1) {
1706             error_report("No support for concatenating multiple snapshot");
1707             ret = -1;
1708             goto out;
1709         }
1710 
1711         bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err);
1712     }
1713     if (local_err) {
1714         error_report("Failed to load snapshot: %s",
1715                      error_get_pretty(local_err));
1716         error_free(local_err);
1717         ret = -1;
1718         goto out;
1719     }
1720 
1721     /* Find driver and parse its options */
1722     drv = bdrv_find_format(out_fmt);
1723     if (!drv) {
1724         error_report("Unknown file format '%s'", out_fmt);
1725         ret = -1;
1726         goto out;
1727     }
1728 
1729     proto_drv = bdrv_find_protocol(out_filename, true, &local_err);
1730     if (!proto_drv) {
1731         error_report_err(local_err);
1732         ret = -1;
1733         goto out;
1734     }
1735 
1736     if (!skip_create) {
1737         if (!drv->create_opts) {
1738             error_report("Format driver '%s' does not support image creation",
1739                          drv->format_name);
1740             ret = -1;
1741             goto out;
1742         }
1743 
1744         if (!proto_drv->create_opts) {
1745             error_report("Protocol driver '%s' does not support image creation",
1746                          proto_drv->format_name);
1747             ret = -1;
1748             goto out;
1749         }
1750 
1751         create_opts = qemu_opts_append(create_opts, drv->create_opts);
1752         create_opts = qemu_opts_append(create_opts, proto_drv->create_opts);
1753 
1754         opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
1755         if (options) {
1756             qemu_opts_do_parse(opts, options, NULL, &local_err);
1757             if (local_err) {
1758                 error_report_err(local_err);
1759                 ret = -1;
1760                 goto out;
1761             }
1762         }
1763 
1764         qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_sectors * 512,
1765                             &error_abort);
1766         ret = add_old_style_options(out_fmt, opts, out_baseimg, NULL);
1767         if (ret < 0) {
1768             goto out;
1769         }
1770     }
1771 
1772     /* Get backing file name if -o backing_file was used */
1773     out_baseimg_param = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE);
1774     if (out_baseimg_param) {
1775         out_baseimg = out_baseimg_param;
1776     }
1777 
1778     /* Check if compression is supported */
1779     if (compress) {
1780         bool encryption =
1781             qemu_opt_get_bool(opts, BLOCK_OPT_ENCRYPT, false);
1782         const char *preallocation =
1783             qemu_opt_get(opts, BLOCK_OPT_PREALLOC);
1784 
1785         if (!drv->bdrv_write_compressed) {
1786             error_report("Compression not supported for this file format");
1787             ret = -1;
1788             goto out;
1789         }
1790 
1791         if (encryption) {
1792             error_report("Compression and encryption not supported at "
1793                          "the same time");
1794             ret = -1;
1795             goto out;
1796         }
1797 
1798         if (preallocation
1799             && strcmp(preallocation, "off"))
1800         {
1801             error_report("Compression and preallocation not supported at "
1802                          "the same time");
1803             ret = -1;
1804             goto out;
1805         }
1806     }
1807 
1808     if (!skip_create) {
1809         /* Create the new image */
1810         ret = bdrv_create(drv, out_filename, opts, &local_err);
1811         if (ret < 0) {
1812             error_report("%s: error while converting %s: %s",
1813                          out_filename, out_fmt, error_get_pretty(local_err));
1814             error_free(local_err);
1815             goto out;
1816         }
1817     }
1818 
1819     flags = min_sparse ? (BDRV_O_RDWR | BDRV_O_UNMAP) : BDRV_O_RDWR;
1820     ret = bdrv_parse_cache_flags(cache, &flags);
1821     if (ret < 0) {
1822         error_report("Invalid cache option: %s", cache);
1823         goto out;
1824     }
1825 
1826     out_blk = img_open("target", out_filename, out_fmt, flags, true, quiet);
1827     if (!out_blk) {
1828         ret = -1;
1829         goto out;
1830     }
1831     out_bs = blk_bs(out_blk);
1832 
1833     /* increase bufsectors from the default 4096 (2M) if opt_transfer_length
1834      * or discard_alignment of the out_bs is greater. Limit to 32768 (16MB)
1835      * as maximum. */
1836     bufsectors = MIN(32768,
1837                      MAX(bufsectors, MAX(out_bs->bl.opt_transfer_length,
1838                                          out_bs->bl.discard_alignment))
1839                     );
1840 
1841     if (skip_create) {
1842         int64_t output_sectors = blk_nb_sectors(out_blk);
1843         if (output_sectors < 0) {
1844             error_report("unable to get output image length: %s",
1845                          strerror(-output_sectors));
1846             ret = -1;
1847             goto out;
1848         } else if (output_sectors < total_sectors) {
1849             error_report("output file is smaller than input file");
1850             ret = -1;
1851             goto out;
1852         }
1853     }
1854 
1855     cluster_sectors = 0;
1856     ret = bdrv_get_info(out_bs, &bdi);
1857     if (ret < 0) {
1858         if (compress) {
1859             error_report("could not get block driver info");
1860             goto out;
1861         }
1862     } else {
1863         compress = compress || bdi.needs_compressed_writes;
1864         cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE;
1865     }
1866 
1867     state = (ImgConvertState) {
1868         .src                = blk,
1869         .src_sectors        = bs_sectors,
1870         .src_num            = bs_n,
1871         .total_sectors      = total_sectors,
1872         .target             = out_blk,
1873         .compressed         = compress,
1874         .target_has_backing = (bool) out_baseimg,
1875         .min_sparse         = min_sparse,
1876         .cluster_sectors    = cluster_sectors,
1877         .buf_sectors        = bufsectors,
1878     };
1879     ret = convert_do_copy(&state);
1880 
1881 out:
1882     if (!ret) {
1883         qemu_progress_print(100, 0);
1884     }
1885     qemu_progress_end();
1886     qemu_opts_del(opts);
1887     qemu_opts_free(create_opts);
1888     qemu_opts_del(sn_opts);
1889     blk_unref(out_blk);
1890     g_free(bs);
1891     if (blk) {
1892         for (bs_i = 0; bs_i < bs_n; bs_i++) {
1893             blk_unref(blk[bs_i]);
1894         }
1895         g_free(blk);
1896     }
1897     g_free(bs_sectors);
1898 fail_getopt:
1899     g_free(options);
1900 
1901     if (ret) {
1902         return 1;
1903     }
1904     return 0;
1905 }
1906 
1907 
1908 static void dump_snapshots(BlockDriverState *bs)
1909 {
1910     QEMUSnapshotInfo *sn_tab, *sn;
1911     int nb_sns, i;
1912 
1913     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1914     if (nb_sns <= 0)
1915         return;
1916     printf("Snapshot list:\n");
1917     bdrv_snapshot_dump(fprintf, stdout, NULL);
1918     printf("\n");
1919     for(i = 0; i < nb_sns; i++) {
1920         sn = &sn_tab[i];
1921         bdrv_snapshot_dump(fprintf, stdout, sn);
1922         printf("\n");
1923     }
1924     g_free(sn_tab);
1925 }
1926 
1927 static void dump_json_image_info_list(ImageInfoList *list)
1928 {
1929     Error *local_err = NULL;
1930     QString *str;
1931     QmpOutputVisitor *ov = qmp_output_visitor_new();
1932     QObject *obj;
1933     visit_type_ImageInfoList(qmp_output_get_visitor(ov),
1934                              &list, NULL, &local_err);
1935     obj = qmp_output_get_qobject(ov);
1936     str = qobject_to_json_pretty(obj);
1937     assert(str != NULL);
1938     printf("%s\n", qstring_get_str(str));
1939     qobject_decref(obj);
1940     qmp_output_visitor_cleanup(ov);
1941     QDECREF(str);
1942 }
1943 
1944 static void dump_json_image_info(ImageInfo *info)
1945 {
1946     Error *local_err = NULL;
1947     QString *str;
1948     QmpOutputVisitor *ov = qmp_output_visitor_new();
1949     QObject *obj;
1950     visit_type_ImageInfo(qmp_output_get_visitor(ov),
1951                          &info, NULL, &local_err);
1952     obj = qmp_output_get_qobject(ov);
1953     str = qobject_to_json_pretty(obj);
1954     assert(str != NULL);
1955     printf("%s\n", qstring_get_str(str));
1956     qobject_decref(obj);
1957     qmp_output_visitor_cleanup(ov);
1958     QDECREF(str);
1959 }
1960 
1961 static void dump_human_image_info_list(ImageInfoList *list)
1962 {
1963     ImageInfoList *elem;
1964     bool delim = false;
1965 
1966     for (elem = list; elem; elem = elem->next) {
1967         if (delim) {
1968             printf("\n");
1969         }
1970         delim = true;
1971 
1972         bdrv_image_info_dump(fprintf, stdout, elem->value);
1973     }
1974 }
1975 
1976 static gboolean str_equal_func(gconstpointer a, gconstpointer b)
1977 {
1978     return strcmp(a, b) == 0;
1979 }
1980 
1981 /**
1982  * Open an image file chain and return an ImageInfoList
1983  *
1984  * @filename: topmost image filename
1985  * @fmt: topmost image format (may be NULL to autodetect)
1986  * @chain: true  - enumerate entire backing file chain
1987  *         false - only topmost image file
1988  *
1989  * Returns a list of ImageInfo objects or NULL if there was an error opening an
1990  * image file.  If there was an error a message will have been printed to
1991  * stderr.
1992  */
1993 static ImageInfoList *collect_image_info_list(const char *filename,
1994                                               const char *fmt,
1995                                               bool chain)
1996 {
1997     ImageInfoList *head = NULL;
1998     ImageInfoList **last = &head;
1999     GHashTable *filenames;
2000     Error *err = NULL;
2001 
2002     filenames = g_hash_table_new_full(g_str_hash, str_equal_func, NULL, NULL);
2003 
2004     while (filename) {
2005         BlockBackend *blk;
2006         BlockDriverState *bs;
2007         ImageInfo *info;
2008         ImageInfoList *elem;
2009 
2010         if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
2011             error_report("Backing file '%s' creates an infinite loop.",
2012                          filename);
2013             goto err;
2014         }
2015         g_hash_table_insert(filenames, (gpointer)filename, NULL);
2016 
2017         blk = img_open("image", filename, fmt,
2018                        BDRV_O_FLAGS | BDRV_O_NO_BACKING, false, false);
2019         if (!blk) {
2020             goto err;
2021         }
2022         bs = blk_bs(blk);
2023 
2024         bdrv_query_image_info(bs, &info, &err);
2025         if (err) {
2026             error_report_err(err);
2027             blk_unref(blk);
2028             goto err;
2029         }
2030 
2031         elem = g_new0(ImageInfoList, 1);
2032         elem->value = info;
2033         *last = elem;
2034         last = &elem->next;
2035 
2036         blk_unref(blk);
2037 
2038         filename = fmt = NULL;
2039         if (chain) {
2040             if (info->has_full_backing_filename) {
2041                 filename = info->full_backing_filename;
2042             } else if (info->has_backing_filename) {
2043                 filename = info->backing_filename;
2044             }
2045             if (info->has_backing_filename_format) {
2046                 fmt = info->backing_filename_format;
2047             }
2048         }
2049     }
2050     g_hash_table_destroy(filenames);
2051     return head;
2052 
2053 err:
2054     qapi_free_ImageInfoList(head);
2055     g_hash_table_destroy(filenames);
2056     return NULL;
2057 }
2058 
2059 static int img_info(int argc, char **argv)
2060 {
2061     int c;
2062     OutputFormat output_format = OFORMAT_HUMAN;
2063     bool chain = false;
2064     const char *filename, *fmt, *output;
2065     ImageInfoList *list;
2066 
2067     fmt = NULL;
2068     output = NULL;
2069     for(;;) {
2070         int option_index = 0;
2071         static const struct option long_options[] = {
2072             {"help", no_argument, 0, 'h'},
2073             {"format", required_argument, 0, 'f'},
2074             {"output", required_argument, 0, OPTION_OUTPUT},
2075             {"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
2076             {0, 0, 0, 0}
2077         };
2078         c = getopt_long(argc, argv, "f:h",
2079                         long_options, &option_index);
2080         if (c == -1) {
2081             break;
2082         }
2083         switch(c) {
2084         case '?':
2085         case 'h':
2086             help();
2087             break;
2088         case 'f':
2089             fmt = optarg;
2090             break;
2091         case OPTION_OUTPUT:
2092             output = optarg;
2093             break;
2094         case OPTION_BACKING_CHAIN:
2095             chain = true;
2096             break;
2097         }
2098     }
2099     if (optind != argc - 1) {
2100         error_exit("Expecting one image file name");
2101     }
2102     filename = argv[optind++];
2103 
2104     if (output && !strcmp(output, "json")) {
2105         output_format = OFORMAT_JSON;
2106     } else if (output && !strcmp(output, "human")) {
2107         output_format = OFORMAT_HUMAN;
2108     } else if (output) {
2109         error_report("--output must be used with human or json as argument.");
2110         return 1;
2111     }
2112 
2113     list = collect_image_info_list(filename, fmt, chain);
2114     if (!list) {
2115         return 1;
2116     }
2117 
2118     switch (output_format) {
2119     case OFORMAT_HUMAN:
2120         dump_human_image_info_list(list);
2121         break;
2122     case OFORMAT_JSON:
2123         if (chain) {
2124             dump_json_image_info_list(list);
2125         } else {
2126             dump_json_image_info(list->value);
2127         }
2128         break;
2129     }
2130 
2131     qapi_free_ImageInfoList(list);
2132     return 0;
2133 }
2134 
2135 
2136 typedef struct MapEntry {
2137     int flags;
2138     int depth;
2139     int64_t start;
2140     int64_t length;
2141     int64_t offset;
2142     BlockDriverState *bs;
2143 } MapEntry;
2144 
2145 static void dump_map_entry(OutputFormat output_format, MapEntry *e,
2146                            MapEntry *next)
2147 {
2148     switch (output_format) {
2149     case OFORMAT_HUMAN:
2150         if ((e->flags & BDRV_BLOCK_DATA) &&
2151             !(e->flags & BDRV_BLOCK_OFFSET_VALID)) {
2152             error_report("File contains external, encrypted or compressed clusters.");
2153             exit(1);
2154         }
2155         if ((e->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) == BDRV_BLOCK_DATA) {
2156             printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
2157                    e->start, e->length, e->offset, e->bs->filename);
2158         }
2159         /* This format ignores the distinction between 0, ZERO and ZERO|DATA.
2160          * Modify the flags here to allow more coalescing.
2161          */
2162         if (next &&
2163             (next->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) != BDRV_BLOCK_DATA) {
2164             next->flags &= ~BDRV_BLOCK_DATA;
2165             next->flags |= BDRV_BLOCK_ZERO;
2166         }
2167         break;
2168     case OFORMAT_JSON:
2169         printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64", \"depth\": %d,"
2170                " \"zero\": %s, \"data\": %s",
2171                (e->start == 0 ? "[" : ",\n"),
2172                e->start, e->length, e->depth,
2173                (e->flags & BDRV_BLOCK_ZERO) ? "true" : "false",
2174                (e->flags & BDRV_BLOCK_DATA) ? "true" : "false");
2175         if (e->flags & BDRV_BLOCK_OFFSET_VALID) {
2176             printf(", \"offset\": %"PRId64"", e->offset);
2177         }
2178         putchar('}');
2179 
2180         if (!next) {
2181             printf("]\n");
2182         }
2183         break;
2184     }
2185 }
2186 
2187 static int get_block_status(BlockDriverState *bs, int64_t sector_num,
2188                             int nb_sectors, MapEntry *e)
2189 {
2190     int64_t ret;
2191     int depth;
2192 
2193     /* As an optimization, we could cache the current range of unallocated
2194      * clusters in each file of the chain, and avoid querying the same
2195      * range repeatedly.
2196      */
2197 
2198     depth = 0;
2199     for (;;) {
2200         ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors);
2201         if (ret < 0) {
2202             return ret;
2203         }
2204         assert(nb_sectors);
2205         if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
2206             break;
2207         }
2208         bs = backing_bs(bs);
2209         if (bs == NULL) {
2210             ret = 0;
2211             break;
2212         }
2213 
2214         depth++;
2215     }
2216 
2217     e->start = sector_num * BDRV_SECTOR_SIZE;
2218     e->length = nb_sectors * BDRV_SECTOR_SIZE;
2219     e->flags = ret & ~BDRV_BLOCK_OFFSET_MASK;
2220     e->offset = ret & BDRV_BLOCK_OFFSET_MASK;
2221     e->depth = depth;
2222     e->bs = bs;
2223     return 0;
2224 }
2225 
2226 static int img_map(int argc, char **argv)
2227 {
2228     int c;
2229     OutputFormat output_format = OFORMAT_HUMAN;
2230     BlockBackend *blk;
2231     BlockDriverState *bs;
2232     const char *filename, *fmt, *output;
2233     int64_t length;
2234     MapEntry curr = { .length = 0 }, next;
2235     int ret = 0;
2236 
2237     fmt = NULL;
2238     output = NULL;
2239     for (;;) {
2240         int option_index = 0;
2241         static const struct option long_options[] = {
2242             {"help", no_argument, 0, 'h'},
2243             {"format", required_argument, 0, 'f'},
2244             {"output", required_argument, 0, OPTION_OUTPUT},
2245             {0, 0, 0, 0}
2246         };
2247         c = getopt_long(argc, argv, "f:h",
2248                         long_options, &option_index);
2249         if (c == -1) {
2250             break;
2251         }
2252         switch (c) {
2253         case '?':
2254         case 'h':
2255             help();
2256             break;
2257         case 'f':
2258             fmt = optarg;
2259             break;
2260         case OPTION_OUTPUT:
2261             output = optarg;
2262             break;
2263         }
2264     }
2265     if (optind != argc - 1) {
2266         error_exit("Expecting one image file name");
2267     }
2268     filename = argv[optind];
2269 
2270     if (output && !strcmp(output, "json")) {
2271         output_format = OFORMAT_JSON;
2272     } else if (output && !strcmp(output, "human")) {
2273         output_format = OFORMAT_HUMAN;
2274     } else if (output) {
2275         error_report("--output must be used with human or json as argument.");
2276         return 1;
2277     }
2278 
2279     blk = img_open("image", filename, fmt, BDRV_O_FLAGS, true, false);
2280     if (!blk) {
2281         return 1;
2282     }
2283     bs = blk_bs(blk);
2284 
2285     if (output_format == OFORMAT_HUMAN) {
2286         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
2287     }
2288 
2289     length = blk_getlength(blk);
2290     while (curr.start + curr.length < length) {
2291         int64_t nsectors_left;
2292         int64_t sector_num;
2293         int n;
2294 
2295         sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
2296 
2297         /* Probe up to 1 GiB at a time.  */
2298         nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
2299         n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
2300         ret = get_block_status(bs, sector_num, n, &next);
2301 
2302         if (ret < 0) {
2303             error_report("Could not read file metadata: %s", strerror(-ret));
2304             goto out;
2305         }
2306 
2307         if (curr.length != 0 && curr.flags == next.flags &&
2308             curr.depth == next.depth &&
2309             ((curr.flags & BDRV_BLOCK_OFFSET_VALID) == 0 ||
2310              curr.offset + curr.length == next.offset)) {
2311             curr.length += next.length;
2312             continue;
2313         }
2314 
2315         if (curr.length > 0) {
2316             dump_map_entry(output_format, &curr, &next);
2317         }
2318         curr = next;
2319     }
2320 
2321     dump_map_entry(output_format, &curr, NULL);
2322 
2323 out:
2324     blk_unref(blk);
2325     return ret < 0;
2326 }
2327 
2328 #define SNAPSHOT_LIST   1
2329 #define SNAPSHOT_CREATE 2
2330 #define SNAPSHOT_APPLY  3
2331 #define SNAPSHOT_DELETE 4
2332 
2333 static int img_snapshot(int argc, char **argv)
2334 {
2335     BlockBackend *blk;
2336     BlockDriverState *bs;
2337     QEMUSnapshotInfo sn;
2338     char *filename, *snapshot_name = NULL;
2339     int c, ret = 0, bdrv_oflags;
2340     int action = 0;
2341     qemu_timeval tv;
2342     bool quiet = false;
2343     Error *err = NULL;
2344 
2345     bdrv_oflags = BDRV_O_FLAGS | BDRV_O_RDWR;
2346     /* Parse commandline parameters */
2347     for(;;) {
2348         c = getopt(argc, argv, "la:c:d:hq");
2349         if (c == -1) {
2350             break;
2351         }
2352         switch(c) {
2353         case '?':
2354         case 'h':
2355             help();
2356             return 0;
2357         case 'l':
2358             if (action) {
2359                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2360                 return 0;
2361             }
2362             action = SNAPSHOT_LIST;
2363             bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */
2364             break;
2365         case 'a':
2366             if (action) {
2367                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2368                 return 0;
2369             }
2370             action = SNAPSHOT_APPLY;
2371             snapshot_name = optarg;
2372             break;
2373         case 'c':
2374             if (action) {
2375                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2376                 return 0;
2377             }
2378             action = SNAPSHOT_CREATE;
2379             snapshot_name = optarg;
2380             break;
2381         case 'd':
2382             if (action) {
2383                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2384                 return 0;
2385             }
2386             action = SNAPSHOT_DELETE;
2387             snapshot_name = optarg;
2388             break;
2389         case 'q':
2390             quiet = true;
2391             break;
2392         }
2393     }
2394 
2395     if (optind != argc - 1) {
2396         error_exit("Expecting one image file name");
2397     }
2398     filename = argv[optind++];
2399 
2400     /* Open the image */
2401     blk = img_open("image", filename, NULL, bdrv_oflags, true, quiet);
2402     if (!blk) {
2403         return 1;
2404     }
2405     bs = blk_bs(blk);
2406 
2407     /* Perform the requested action */
2408     switch(action) {
2409     case SNAPSHOT_LIST:
2410         dump_snapshots(bs);
2411         break;
2412 
2413     case SNAPSHOT_CREATE:
2414         memset(&sn, 0, sizeof(sn));
2415         pstrcpy(sn.name, sizeof(sn.name), snapshot_name);
2416 
2417         qemu_gettimeofday(&tv);
2418         sn.date_sec = tv.tv_sec;
2419         sn.date_nsec = tv.tv_usec * 1000;
2420 
2421         ret = bdrv_snapshot_create(bs, &sn);
2422         if (ret) {
2423             error_report("Could not create snapshot '%s': %d (%s)",
2424                 snapshot_name, ret, strerror(-ret));
2425         }
2426         break;
2427 
2428     case SNAPSHOT_APPLY:
2429         ret = bdrv_snapshot_goto(bs, snapshot_name);
2430         if (ret) {
2431             error_report("Could not apply snapshot '%s': %d (%s)",
2432                 snapshot_name, ret, strerror(-ret));
2433         }
2434         break;
2435 
2436     case SNAPSHOT_DELETE:
2437         bdrv_snapshot_delete_by_id_or_name(bs, snapshot_name, &err);
2438         if (err) {
2439             error_report("Could not delete snapshot '%s': (%s)",
2440                          snapshot_name, error_get_pretty(err));
2441             error_free(err);
2442             ret = 1;
2443         }
2444         break;
2445     }
2446 
2447     /* Cleanup */
2448     blk_unref(blk);
2449     if (ret) {
2450         return 1;
2451     }
2452     return 0;
2453 }
2454 
2455 static int img_rebase(int argc, char **argv)
2456 {
2457     BlockBackend *blk = NULL, *blk_old_backing = NULL, *blk_new_backing = NULL;
2458     BlockDriverState *bs = NULL;
2459     char *filename;
2460     const char *fmt, *cache, *src_cache, *out_basefmt, *out_baseimg;
2461     int c, flags, src_flags, ret;
2462     int unsafe = 0;
2463     int progress = 0;
2464     bool quiet = false;
2465     Error *local_err = NULL;
2466 
2467     /* Parse commandline parameters */
2468     fmt = NULL;
2469     cache = BDRV_DEFAULT_CACHE;
2470     src_cache = BDRV_DEFAULT_CACHE;
2471     out_baseimg = NULL;
2472     out_basefmt = NULL;
2473     for(;;) {
2474         c = getopt(argc, argv, "hf:F:b:upt:T:q");
2475         if (c == -1) {
2476             break;
2477         }
2478         switch(c) {
2479         case '?':
2480         case 'h':
2481             help();
2482             return 0;
2483         case 'f':
2484             fmt = optarg;
2485             break;
2486         case 'F':
2487             out_basefmt = optarg;
2488             break;
2489         case 'b':
2490             out_baseimg = optarg;
2491             break;
2492         case 'u':
2493             unsafe = 1;
2494             break;
2495         case 'p':
2496             progress = 1;
2497             break;
2498         case 't':
2499             cache = optarg;
2500             break;
2501         case 'T':
2502             src_cache = optarg;
2503             break;
2504         case 'q':
2505             quiet = true;
2506             break;
2507         }
2508     }
2509 
2510     if (quiet) {
2511         progress = 0;
2512     }
2513 
2514     if (optind != argc - 1) {
2515         error_exit("Expecting one image file name");
2516     }
2517     if (!unsafe && !out_baseimg) {
2518         error_exit("Must specify backing file (-b) or use unsafe mode (-u)");
2519     }
2520     filename = argv[optind++];
2521 
2522     qemu_progress_init(progress, 2.0);
2523     qemu_progress_print(0, 100);
2524 
2525     flags = BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0);
2526     ret = bdrv_parse_cache_flags(cache, &flags);
2527     if (ret < 0) {
2528         error_report("Invalid cache option: %s", cache);
2529         goto out;
2530     }
2531 
2532     src_flags = BDRV_O_FLAGS;
2533     ret = bdrv_parse_cache_flags(src_cache, &src_flags);
2534     if (ret < 0) {
2535         error_report("Invalid source cache option: %s", src_cache);
2536         goto out;
2537     }
2538 
2539     /*
2540      * Open the images.
2541      *
2542      * Ignore the old backing file for unsafe rebase in case we want to correct
2543      * the reference to a renamed or moved backing file.
2544      */
2545     blk = img_open("image", filename, fmt, flags, true, quiet);
2546     if (!blk) {
2547         ret = -1;
2548         goto out;
2549     }
2550     bs = blk_bs(blk);
2551 
2552     if (out_basefmt != NULL) {
2553         if (bdrv_find_format(out_basefmt) == NULL) {
2554             error_report("Invalid format name: '%s'", out_basefmt);
2555             ret = -1;
2556             goto out;
2557         }
2558     }
2559 
2560     /* For safe rebasing we need to compare old and new backing file */
2561     if (!unsafe) {
2562         char backing_name[PATH_MAX];
2563         QDict *options = NULL;
2564 
2565         if (bs->backing_format[0] != '\0') {
2566             options = qdict_new();
2567             qdict_put(options, "driver", qstring_from_str(bs->backing_format));
2568         }
2569 
2570         bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2571         blk_old_backing = blk_new_open("old_backing", backing_name, NULL,
2572                                        options, src_flags, &local_err);
2573         if (!blk_old_backing) {
2574             error_report("Could not open old backing file '%s': %s",
2575                          backing_name, error_get_pretty(local_err));
2576             error_free(local_err);
2577             goto out;
2578         }
2579 
2580         if (out_baseimg[0]) {
2581             if (out_basefmt) {
2582                 options = qdict_new();
2583                 qdict_put(options, "driver", qstring_from_str(out_basefmt));
2584             } else {
2585                 options = NULL;
2586             }
2587 
2588             blk_new_backing = blk_new_open("new_backing", out_baseimg, NULL,
2589                                            options, src_flags, &local_err);
2590             if (!blk_new_backing) {
2591                 error_report("Could not open new backing file '%s': %s",
2592                              out_baseimg, error_get_pretty(local_err));
2593                 error_free(local_err);
2594                 goto out;
2595             }
2596         }
2597     }
2598 
2599     /*
2600      * Check each unallocated cluster in the COW file. If it is unallocated,
2601      * accesses go to the backing file. We must therefore compare this cluster
2602      * in the old and new backing file, and if they differ we need to copy it
2603      * from the old backing file into the COW file.
2604      *
2605      * If qemu-img crashes during this step, no harm is done. The content of
2606      * the image is the same as the original one at any time.
2607      */
2608     if (!unsafe) {
2609         int64_t num_sectors;
2610         int64_t old_backing_num_sectors;
2611         int64_t new_backing_num_sectors = 0;
2612         uint64_t sector;
2613         int n;
2614         uint8_t * buf_old;
2615         uint8_t * buf_new;
2616         float local_progress = 0;
2617 
2618         buf_old = blk_blockalign(blk, IO_BUF_SIZE);
2619         buf_new = blk_blockalign(blk, IO_BUF_SIZE);
2620 
2621         num_sectors = blk_nb_sectors(blk);
2622         if (num_sectors < 0) {
2623             error_report("Could not get size of '%s': %s",
2624                          filename, strerror(-num_sectors));
2625             ret = -1;
2626             goto out;
2627         }
2628         old_backing_num_sectors = blk_nb_sectors(blk_old_backing);
2629         if (old_backing_num_sectors < 0) {
2630             char backing_name[PATH_MAX];
2631 
2632             bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2633             error_report("Could not get size of '%s': %s",
2634                          backing_name, strerror(-old_backing_num_sectors));
2635             ret = -1;
2636             goto out;
2637         }
2638         if (blk_new_backing) {
2639             new_backing_num_sectors = blk_nb_sectors(blk_new_backing);
2640             if (new_backing_num_sectors < 0) {
2641                 error_report("Could not get size of '%s': %s",
2642                              out_baseimg, strerror(-new_backing_num_sectors));
2643                 ret = -1;
2644                 goto out;
2645             }
2646         }
2647 
2648         if (num_sectors != 0) {
2649             local_progress = (float)100 /
2650                 (num_sectors / MIN(num_sectors, IO_BUF_SIZE / 512));
2651         }
2652 
2653         for (sector = 0; sector < num_sectors; sector += n) {
2654 
2655             /* How many sectors can we handle with the next read? */
2656             if (sector + (IO_BUF_SIZE / 512) <= num_sectors) {
2657                 n = (IO_BUF_SIZE / 512);
2658             } else {
2659                 n = num_sectors - sector;
2660             }
2661 
2662             /* If the cluster is allocated, we don't need to take action */
2663             ret = bdrv_is_allocated(bs, sector, n, &n);
2664             if (ret < 0) {
2665                 error_report("error while reading image metadata: %s",
2666                              strerror(-ret));
2667                 goto out;
2668             }
2669             if (ret) {
2670                 continue;
2671             }
2672 
2673             /*
2674              * Read old and new backing file and take into consideration that
2675              * backing files may be smaller than the COW image.
2676              */
2677             if (sector >= old_backing_num_sectors) {
2678                 memset(buf_old, 0, n * BDRV_SECTOR_SIZE);
2679             } else {
2680                 if (sector + n > old_backing_num_sectors) {
2681                     n = old_backing_num_sectors - sector;
2682                 }
2683 
2684                 ret = blk_read(blk_old_backing, sector, buf_old, n);
2685                 if (ret < 0) {
2686                     error_report("error while reading from old backing file");
2687                     goto out;
2688                 }
2689             }
2690 
2691             if (sector >= new_backing_num_sectors || !blk_new_backing) {
2692                 memset(buf_new, 0, n * BDRV_SECTOR_SIZE);
2693             } else {
2694                 if (sector + n > new_backing_num_sectors) {
2695                     n = new_backing_num_sectors - sector;
2696                 }
2697 
2698                 ret = blk_read(blk_new_backing, sector, buf_new, n);
2699                 if (ret < 0) {
2700                     error_report("error while reading from new backing file");
2701                     goto out;
2702                 }
2703             }
2704 
2705             /* If they differ, we need to write to the COW file */
2706             uint64_t written = 0;
2707 
2708             while (written < n) {
2709                 int pnum;
2710 
2711                 if (compare_sectors(buf_old + written * 512,
2712                     buf_new + written * 512, n - written, &pnum))
2713                 {
2714                     ret = blk_write(blk, sector + written,
2715                                     buf_old + written * 512, pnum);
2716                     if (ret < 0) {
2717                         error_report("Error while writing to COW image: %s",
2718                             strerror(-ret));
2719                         goto out;
2720                     }
2721                 }
2722 
2723                 written += pnum;
2724             }
2725             qemu_progress_print(local_progress, 100);
2726         }
2727 
2728         qemu_vfree(buf_old);
2729         qemu_vfree(buf_new);
2730     }
2731 
2732     /*
2733      * Change the backing file. All clusters that are different from the old
2734      * backing file are overwritten in the COW file now, so the visible content
2735      * doesn't change when we switch the backing file.
2736      */
2737     if (out_baseimg && *out_baseimg) {
2738         ret = bdrv_change_backing_file(bs, out_baseimg, out_basefmt);
2739     } else {
2740         ret = bdrv_change_backing_file(bs, NULL, NULL);
2741     }
2742 
2743     if (ret == -ENOSPC) {
2744         error_report("Could not change the backing file to '%s': No "
2745                      "space left in the file header", out_baseimg);
2746     } else if (ret < 0) {
2747         error_report("Could not change the backing file to '%s': %s",
2748             out_baseimg, strerror(-ret));
2749     }
2750 
2751     qemu_progress_print(100, 0);
2752     /*
2753      * TODO At this point it is possible to check if any clusters that are
2754      * allocated in the COW file are the same in the backing file. If so, they
2755      * could be dropped from the COW file. Don't do this before switching the
2756      * backing file, in case of a crash this would lead to corruption.
2757      */
2758 out:
2759     qemu_progress_end();
2760     /* Cleanup */
2761     if (!unsafe) {
2762         blk_unref(blk_old_backing);
2763         blk_unref(blk_new_backing);
2764     }
2765 
2766     blk_unref(blk);
2767     if (ret) {
2768         return 1;
2769     }
2770     return 0;
2771 }
2772 
2773 static int img_resize(int argc, char **argv)
2774 {
2775     Error *err = NULL;
2776     int c, ret, relative;
2777     const char *filename, *fmt, *size;
2778     int64_t n, total_size;
2779     bool quiet = false;
2780     BlockBackend *blk = NULL;
2781     QemuOpts *param;
2782     static QemuOptsList resize_options = {
2783         .name = "resize_options",
2784         .head = QTAILQ_HEAD_INITIALIZER(resize_options.head),
2785         .desc = {
2786             {
2787                 .name = BLOCK_OPT_SIZE,
2788                 .type = QEMU_OPT_SIZE,
2789                 .help = "Virtual disk size"
2790             }, {
2791                 /* end of list */
2792             }
2793         },
2794     };
2795 
2796     /* Remove size from argv manually so that negative numbers are not treated
2797      * as options by getopt. */
2798     if (argc < 3) {
2799         error_exit("Not enough arguments");
2800         return 1;
2801     }
2802 
2803     size = argv[--argc];
2804 
2805     /* Parse getopt arguments */
2806     fmt = NULL;
2807     for(;;) {
2808         c = getopt(argc, argv, "f:hq");
2809         if (c == -1) {
2810             break;
2811         }
2812         switch(c) {
2813         case '?':
2814         case 'h':
2815             help();
2816             break;
2817         case 'f':
2818             fmt = optarg;
2819             break;
2820         case 'q':
2821             quiet = true;
2822             break;
2823         }
2824     }
2825     if (optind != argc - 1) {
2826         error_exit("Expecting one image file name");
2827     }
2828     filename = argv[optind++];
2829 
2830     /* Choose grow, shrink, or absolute resize mode */
2831     switch (size[0]) {
2832     case '+':
2833         relative = 1;
2834         size++;
2835         break;
2836     case '-':
2837         relative = -1;
2838         size++;
2839         break;
2840     default:
2841         relative = 0;
2842         break;
2843     }
2844 
2845     /* Parse size */
2846     param = qemu_opts_create(&resize_options, NULL, 0, &error_abort);
2847     qemu_opt_set(param, BLOCK_OPT_SIZE, size, &err);
2848     if (err) {
2849         error_report_err(err);
2850         ret = -1;
2851         qemu_opts_del(param);
2852         goto out;
2853     }
2854     n = qemu_opt_get_size(param, BLOCK_OPT_SIZE, 0);
2855     qemu_opts_del(param);
2856 
2857     blk = img_open("image", filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR,
2858                    true, quiet);
2859     if (!blk) {
2860         ret = -1;
2861         goto out;
2862     }
2863 
2864     if (relative) {
2865         total_size = blk_getlength(blk) + n * relative;
2866     } else {
2867         total_size = n;
2868     }
2869     if (total_size <= 0) {
2870         error_report("New image size must be positive");
2871         ret = -1;
2872         goto out;
2873     }
2874 
2875     ret = blk_truncate(blk, total_size);
2876     switch (ret) {
2877     case 0:
2878         qprintf(quiet, "Image resized.\n");
2879         break;
2880     case -ENOTSUP:
2881         error_report("This image does not support resize");
2882         break;
2883     case -EACCES:
2884         error_report("Image is read-only");
2885         break;
2886     default:
2887         error_report("Error resizing image (%d)", -ret);
2888         break;
2889     }
2890 out:
2891     blk_unref(blk);
2892     if (ret) {
2893         return 1;
2894     }
2895     return 0;
2896 }
2897 
2898 static void amend_status_cb(BlockDriverState *bs,
2899                             int64_t offset, int64_t total_work_size)
2900 {
2901     qemu_progress_print(100.f * offset / total_work_size, 0);
2902 }
2903 
2904 static int img_amend(int argc, char **argv)
2905 {
2906     Error *err = NULL;
2907     int c, ret = 0;
2908     char *options = NULL;
2909     QemuOptsList *create_opts = NULL;
2910     QemuOpts *opts = NULL;
2911     const char *fmt = NULL, *filename, *cache;
2912     int flags;
2913     bool quiet = false, progress = false;
2914     BlockBackend *blk = NULL;
2915     BlockDriverState *bs = NULL;
2916 
2917     cache = BDRV_DEFAULT_CACHE;
2918     for (;;) {
2919         c = getopt(argc, argv, "ho:f:t:pq");
2920         if (c == -1) {
2921             break;
2922         }
2923 
2924         switch (c) {
2925             case 'h':
2926             case '?':
2927                 help();
2928                 break;
2929             case 'o':
2930                 if (!is_valid_option_list(optarg)) {
2931                     error_report("Invalid option list: %s", optarg);
2932                     ret = -1;
2933                     goto out_no_progress;
2934                 }
2935                 if (!options) {
2936                     options = g_strdup(optarg);
2937                 } else {
2938                     char *old_options = options;
2939                     options = g_strdup_printf("%s,%s", options, optarg);
2940                     g_free(old_options);
2941                 }
2942                 break;
2943             case 'f':
2944                 fmt = optarg;
2945                 break;
2946             case 't':
2947                 cache = optarg;
2948                 break;
2949             case 'p':
2950                 progress = true;
2951                 break;
2952             case 'q':
2953                 quiet = true;
2954                 break;
2955         }
2956     }
2957 
2958     if (!options) {
2959         error_exit("Must specify options (-o)");
2960     }
2961 
2962     if (quiet) {
2963         progress = false;
2964     }
2965     qemu_progress_init(progress, 1.0);
2966 
2967     filename = (optind == argc - 1) ? argv[argc - 1] : NULL;
2968     if (fmt && has_help_option(options)) {
2969         /* If a format is explicitly specified (and possibly no filename is
2970          * given), print option help here */
2971         ret = print_block_option_help(filename, fmt);
2972         goto out;
2973     }
2974 
2975     if (optind != argc - 1) {
2976         error_report("Expecting one image file name");
2977         ret = -1;
2978         goto out;
2979     }
2980 
2981     flags = BDRV_O_FLAGS | BDRV_O_RDWR;
2982     ret = bdrv_parse_cache_flags(cache, &flags);
2983     if (ret < 0) {
2984         error_report("Invalid cache option: %s", cache);
2985         goto out;
2986     }
2987 
2988     blk = img_open("image", filename, fmt, flags, true, quiet);
2989     if (!blk) {
2990         ret = -1;
2991         goto out;
2992     }
2993     bs = blk_bs(blk);
2994 
2995     fmt = bs->drv->format_name;
2996 
2997     if (has_help_option(options)) {
2998         /* If the format was auto-detected, print option help here */
2999         ret = print_block_option_help(filename, fmt);
3000         goto out;
3001     }
3002 
3003     if (!bs->drv->create_opts) {
3004         error_report("Format driver '%s' does not support any options to amend",
3005                      fmt);
3006         ret = -1;
3007         goto out;
3008     }
3009 
3010     create_opts = qemu_opts_append(create_opts, bs->drv->create_opts);
3011     opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
3012     if (options) {
3013         qemu_opts_do_parse(opts, options, NULL, &err);
3014         if (err) {
3015             error_report_err(err);
3016             ret = -1;
3017             goto out;
3018         }
3019     }
3020 
3021     /* In case the driver does not call amend_status_cb() */
3022     qemu_progress_print(0.f, 0);
3023     ret = bdrv_amend_options(bs, opts, &amend_status_cb);
3024     qemu_progress_print(100.f, 0);
3025     if (ret < 0) {
3026         error_report("Error while amending options: %s", strerror(-ret));
3027         goto out;
3028     }
3029 
3030 out:
3031     qemu_progress_end();
3032 
3033 out_no_progress:
3034     blk_unref(blk);
3035     qemu_opts_del(opts);
3036     qemu_opts_free(create_opts);
3037     g_free(options);
3038 
3039     if (ret) {
3040         return 1;
3041     }
3042     return 0;
3043 }
3044 
3045 static const img_cmd_t img_cmds[] = {
3046 #define DEF(option, callback, arg_string)        \
3047     { option, callback },
3048 #include "qemu-img-cmds.h"
3049 #undef DEF
3050 #undef GEN_DOCS
3051     { NULL, NULL, },
3052 };
3053 
3054 int main(int argc, char **argv)
3055 {
3056     const img_cmd_t *cmd;
3057     const char *cmdname;
3058     Error *local_error = NULL;
3059     int c;
3060     static const struct option long_options[] = {
3061         {"help", no_argument, 0, 'h'},
3062         {"version", no_argument, 0, 'v'},
3063         {0, 0, 0, 0}
3064     };
3065 
3066 #ifdef CONFIG_POSIX
3067     signal(SIGPIPE, SIG_IGN);
3068 #endif
3069 
3070     error_set_progname(argv[0]);
3071     qemu_init_exec_dir(argv[0]);
3072 
3073     if (qemu_init_main_loop(&local_error)) {
3074         error_report_err(local_error);
3075         exit(EXIT_FAILURE);
3076     }
3077 
3078     bdrv_init();
3079     if (argc < 2) {
3080         error_exit("Not enough arguments");
3081     }
3082     cmdname = argv[1];
3083 
3084     /* find the command */
3085     for (cmd = img_cmds; cmd->name != NULL; cmd++) {
3086         if (!strcmp(cmdname, cmd->name)) {
3087             return cmd->handler(argc - 1, argv + 1);
3088         }
3089     }
3090 
3091     c = getopt_long(argc, argv, "h", long_options, NULL);
3092 
3093     if (c == 'h') {
3094         help();
3095     }
3096     if (c == 'v') {
3097         printf(QEMU_IMG_VERSION);
3098         return 0;
3099     }
3100 
3101     /* not found */
3102     error_exit("Command not found: %s", cmdname);
3103 }
3104