xref: /openbmc/qemu/qemu-img.c (revision bfb27e60)
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/qjson.h"
27 #include "qemu-common.h"
28 #include "qemu/option.h"
29 #include "qemu/error-report.h"
30 #include "qemu/osdep.h"
31 #include "sysemu/sysemu.h"
32 #include "block/block_int.h"
33 #include "block/qapi.h"
34 #include <getopt.h>
35 
36 #define QEMU_IMG_VERSION "qemu-img version " QEMU_VERSION \
37                           ", Copyright (c) 2004-2008 Fabrice Bellard\n"
38 
39 typedef struct img_cmd_t {
40     const char *name;
41     int (*handler)(int argc, char **argv);
42 } img_cmd_t;
43 
44 enum {
45     OPTION_OUTPUT = 256,
46     OPTION_BACKING_CHAIN = 257,
47 };
48 
49 typedef enum OutputFormat {
50     OFORMAT_JSON,
51     OFORMAT_HUMAN,
52 } OutputFormat;
53 
54 /* Default to cache=writeback as data integrity is not important for qemu-tcg. */
55 #define BDRV_O_FLAGS BDRV_O_CACHE_WB
56 #define BDRV_DEFAULT_CACHE "writeback"
57 
58 static void format_print(void *opaque, const char *name)
59 {
60     printf(" %s", name);
61 }
62 
63 static void QEMU_NORETURN GCC_FMT_ATTR(1, 2) error_exit(const char *fmt, ...)
64 {
65     va_list ap;
66 
67     error_printf("qemu-img: ");
68 
69     va_start(ap, fmt);
70     error_vprintf(fmt, ap);
71     va_end(ap);
72 
73     error_printf("\nTry 'qemu-img --help' for more information\n");
74     exit(EXIT_FAILURE);
75 }
76 
77 /* Please keep in synch with qemu-img.texi */
78 static void QEMU_NORETURN help(void)
79 {
80     const char *help_msg =
81            QEMU_IMG_VERSION
82            "usage: qemu-img command [command options]\n"
83            "QEMU disk image utility\n"
84            "\n"
85            "Command syntax:\n"
86 #define DEF(option, callback, arg_string)        \
87            "  " arg_string "\n"
88 #include "qemu-img-cmds.h"
89 #undef DEF
90 #undef GEN_DOCS
91            "\n"
92            "Command parameters:\n"
93            "  'filename' is a disk image filename\n"
94            "  'fmt' is the disk image format. It is guessed automatically in most cases\n"
95            "  'cache' is the cache mode used to write the output disk image, the valid\n"
96            "    options are: 'none', 'writeback' (default, except for convert), 'writethrough',\n"
97            "    'directsync' and 'unsafe' (default for convert)\n"
98            "  'src_cache' is the cache mode used to read input disk images, the valid\n"
99            "    options are the same as for the 'cache' option\n"
100            "  'size' is the disk image size in bytes. Optional suffixes\n"
101            "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M),\n"
102            "    'T' (terabyte, 1024G), 'P' (petabyte, 1024T) and 'E' (exabyte, 1024P)  are\n"
103            "    supported. 'b' is ignored.\n"
104            "  'output_filename' is the destination disk image filename\n"
105            "  'output_fmt' is the destination format\n"
106            "  'options' is a comma separated list of format specific options in a\n"
107            "    name=value format. Use -o ? for an overview of the options supported by the\n"
108            "    used format\n"
109            "  'snapshot_param' is param used for internal snapshot, format\n"
110            "    is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
111            "    '[ID_OR_NAME]'\n"
112            "  'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n"
113            "    instead\n"
114            "  '-c' indicates that target image must be compressed (qcow format only)\n"
115            "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"
116            "       match exactly. The image doesn't need a working backing file before\n"
117            "       rebasing in this case (useful for renaming the backing file)\n"
118            "  '-h' with or without a command shows this help and lists the supported formats\n"
119            "  '-p' show progress of command (only certain commands)\n"
120            "  '-q' use Quiet mode - do not print any output (except errors)\n"
121            "  '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
122            "       contain only zeros for qemu-img to create a sparse image during\n"
123            "       conversion. If the number of bytes is 0, the source will not be scanned for\n"
124            "       unallocated or zero sectors, and the destination image will always be\n"
125            "       fully allocated\n"
126            "  '--output' takes the format in which the output must be done (human or json)\n"
127            "  '-n' skips the target volume creation (useful if the volume is created\n"
128            "       prior to running qemu-img)\n"
129            "\n"
130            "Parameters to check subcommand:\n"
131            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
132            "       '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"
133            "       kinds of errors, with a higher risk of choosing the wrong fix or\n"
134            "       hiding corruption that has already occurred.\n"
135            "\n"
136            "Parameters to snapshot subcommand:\n"
137            "  'snapshot' is the name of the snapshot to create, apply or delete\n"
138            "  '-a' applies a snapshot (revert disk to saved state)\n"
139            "  '-c' creates a snapshot\n"
140            "  '-d' deletes a snapshot\n"
141            "  '-l' lists all snapshots in the given image\n"
142            "\n"
143            "Parameters to compare subcommand:\n"
144            "  '-f' first image format\n"
145            "  '-F' second image format\n"
146            "  '-s' run in Strict mode - fail on different image size or sector allocation\n";
147 
148     printf("%s\nSupported formats:", help_msg);
149     bdrv_iterate_format(format_print, NULL);
150     printf("\n");
151     exit(EXIT_SUCCESS);
152 }
153 
154 static int GCC_FMT_ATTR(2, 3) qprintf(bool quiet, const char *fmt, ...)
155 {
156     int ret = 0;
157     if (!quiet) {
158         va_list args;
159         va_start(args, fmt);
160         ret = vprintf(fmt, args);
161         va_end(args);
162     }
163     return ret;
164 }
165 
166 #if defined(WIN32)
167 /* XXX: put correct support for win32 */
168 static int read_password(char *buf, int buf_size)
169 {
170     int c, i;
171 
172     printf("Password: ");
173     fflush(stdout);
174     i = 0;
175     for(;;) {
176         c = getchar();
177         if (c < 0) {
178             buf[i] = '\0';
179             return -1;
180         } else if (c == '\n') {
181             break;
182         } else if (i < (buf_size - 1)) {
183             buf[i++] = c;
184         }
185     }
186     buf[i] = '\0';
187     return 0;
188 }
189 
190 #else
191 
192 #include <termios.h>
193 
194 static struct termios oldtty;
195 
196 static void term_exit(void)
197 {
198     tcsetattr (0, TCSANOW, &oldtty);
199 }
200 
201 static void term_init(void)
202 {
203     struct termios tty;
204 
205     tcgetattr (0, &tty);
206     oldtty = tty;
207 
208     tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
209                           |INLCR|IGNCR|ICRNL|IXON);
210     tty.c_oflag |= OPOST;
211     tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
212     tty.c_cflag &= ~(CSIZE|PARENB);
213     tty.c_cflag |= CS8;
214     tty.c_cc[VMIN] = 1;
215     tty.c_cc[VTIME] = 0;
216 
217     tcsetattr (0, TCSANOW, &tty);
218 
219     atexit(term_exit);
220 }
221 
222 static int read_password(char *buf, int buf_size)
223 {
224     uint8_t ch;
225     int i, ret;
226 
227     printf("password: ");
228     fflush(stdout);
229     term_init();
230     i = 0;
231     for(;;) {
232         ret = read(0, &ch, 1);
233         if (ret == -1) {
234             if (errno == EAGAIN || errno == EINTR) {
235                 continue;
236             } else {
237                 break;
238             }
239         } else if (ret == 0) {
240             ret = -1;
241             break;
242         } else {
243             if (ch == '\r') {
244                 ret = 0;
245                 break;
246             }
247             if (i < (buf_size - 1))
248                 buf[i++] = ch;
249         }
250     }
251     term_exit();
252     buf[i] = '\0';
253     printf("\n");
254     return ret;
255 }
256 #endif
257 
258 static int print_block_option_help(const char *filename, const char *fmt)
259 {
260     BlockDriver *drv, *proto_drv;
261     QemuOptsList *create_opts = NULL;
262 
263     /* Find driver and parse its options */
264     drv = bdrv_find_format(fmt);
265     if (!drv) {
266         error_report("Unknown file format '%s'", fmt);
267         return 1;
268     }
269 
270     create_opts = qemu_opts_append(create_opts, drv->create_opts);
271     if (filename) {
272         proto_drv = bdrv_find_protocol(filename, true);
273         if (!proto_drv) {
274             error_report("Unknown protocol '%s'", filename);
275             qemu_opts_free(create_opts);
276             return 1;
277         }
278         create_opts = qemu_opts_append(create_opts, proto_drv->create_opts);
279     }
280 
281     qemu_opts_print_help(create_opts);
282     qemu_opts_free(create_opts);
283     return 0;
284 }
285 
286 static BlockDriverState *bdrv_new_open(const char *id,
287                                        const char *filename,
288                                        const char *fmt,
289                                        int flags,
290                                        bool require_io,
291                                        bool quiet)
292 {
293     BlockDriverState *bs;
294     BlockDriver *drv;
295     char password[256];
296     Error *local_err = NULL;
297     int ret;
298 
299     bs = bdrv_new(id, &error_abort);
300 
301     if (fmt) {
302         drv = bdrv_find_format(fmt);
303         if (!drv) {
304             error_report("Unknown file format '%s'", fmt);
305             goto fail;
306         }
307     } else {
308         drv = NULL;
309     }
310 
311     ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err);
312     if (ret < 0) {
313         error_report("Could not open '%s': %s", filename,
314                      error_get_pretty(local_err));
315         error_free(local_err);
316         goto fail;
317     }
318 
319     if (bdrv_is_encrypted(bs) && require_io) {
320         qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);
321         if (read_password(password, sizeof(password)) < 0) {
322             error_report("No password given");
323             goto fail;
324         }
325         if (bdrv_set_key(bs, password) < 0) {
326             error_report("invalid password");
327             goto fail;
328         }
329     }
330     return bs;
331 fail:
332     bdrv_unref(bs);
333     return NULL;
334 }
335 
336 static int add_old_style_options(const char *fmt, QemuOpts *opts,
337                                  const char *base_filename,
338                                  const char *base_fmt)
339 {
340     if (base_filename) {
341         if (qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename)) {
342             error_report("Backing file not supported for file format '%s'",
343                          fmt);
344             return -1;
345         }
346     }
347     if (base_fmt) {
348         if (qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt)) {
349             error_report("Backing file format not supported for file "
350                          "format '%s'", fmt);
351             return -1;
352         }
353     }
354     return 0;
355 }
356 
357 static int img_create(int argc, char **argv)
358 {
359     int c;
360     uint64_t img_size = -1;
361     const char *fmt = "raw";
362     const char *base_fmt = NULL;
363     const char *filename;
364     const char *base_filename = NULL;
365     char *options = NULL;
366     Error *local_err = NULL;
367     bool quiet = false;
368 
369     for(;;) {
370         c = getopt(argc, argv, "F:b:f:he6o:q");
371         if (c == -1) {
372             break;
373         }
374         switch(c) {
375         case '?':
376         case 'h':
377             help();
378             break;
379         case 'F':
380             base_fmt = optarg;
381             break;
382         case 'b':
383             base_filename = optarg;
384             break;
385         case 'f':
386             fmt = optarg;
387             break;
388         case 'e':
389             error_report("option -e is deprecated, please use \'-o "
390                   "encryption\' instead!");
391             goto fail;
392         case '6':
393             error_report("option -6 is deprecated, please use \'-o "
394                   "compat6\' instead!");
395             goto fail;
396         case 'o':
397             if (!is_valid_option_list(optarg)) {
398                 error_report("Invalid option list: %s", optarg);
399                 goto fail;
400             }
401             if (!options) {
402                 options = g_strdup(optarg);
403             } else {
404                 char *old_options = options;
405                 options = g_strdup_printf("%s,%s", options, optarg);
406                 g_free(old_options);
407             }
408             break;
409         case 'q':
410             quiet = true;
411             break;
412         }
413     }
414 
415     /* Get the filename */
416     filename = (optind < argc) ? argv[optind] : NULL;
417     if (options && has_help_option(options)) {
418         g_free(options);
419         return print_block_option_help(filename, fmt);
420     }
421 
422     if (optind >= argc) {
423         error_exit("Expecting image file name");
424     }
425     optind++;
426 
427     /* Get image size, if specified */
428     if (optind < argc) {
429         int64_t sval;
430         char *end;
431         sval = strtosz_suffix(argv[optind++], &end, STRTOSZ_DEFSUFFIX_B);
432         if (sval < 0 || *end) {
433             if (sval == -ERANGE) {
434                 error_report("Image size must be less than 8 EiB!");
435             } else {
436                 error_report("Invalid image size specified! You may use k, M, "
437                       "G, T, P or E suffixes for ");
438                 error_report("kilobytes, megabytes, gigabytes, terabytes, "
439                              "petabytes and exabytes.");
440             }
441             goto fail;
442         }
443         img_size = (uint64_t)sval;
444     }
445     if (optind != argc) {
446         error_exit("Unexpected argument: %s", argv[optind]);
447     }
448 
449     bdrv_img_create(filename, fmt, base_filename, base_fmt,
450                     options, img_size, BDRV_O_FLAGS, &local_err, quiet);
451     if (local_err) {
452         error_report("%s: %s", filename, error_get_pretty(local_err));
453         error_free(local_err);
454         goto fail;
455     }
456 
457     g_free(options);
458     return 0;
459 
460 fail:
461     g_free(options);
462     return 1;
463 }
464 
465 static void dump_json_image_check(ImageCheck *check, bool quiet)
466 {
467     Error *local_err = NULL;
468     QString *str;
469     QmpOutputVisitor *ov = qmp_output_visitor_new();
470     QObject *obj;
471     visit_type_ImageCheck(qmp_output_get_visitor(ov),
472                           &check, NULL, &local_err);
473     obj = qmp_output_get_qobject(ov);
474     str = qobject_to_json_pretty(obj);
475     assert(str != NULL);
476     qprintf(quiet, "%s\n", qstring_get_str(str));
477     qobject_decref(obj);
478     qmp_output_visitor_cleanup(ov);
479     QDECREF(str);
480 }
481 
482 static void dump_human_image_check(ImageCheck *check, bool quiet)
483 {
484     if (!(check->corruptions || check->leaks || check->check_errors)) {
485         qprintf(quiet, "No errors were found on the image.\n");
486     } else {
487         if (check->corruptions) {
488             qprintf(quiet, "\n%" PRId64 " errors were found on the image.\n"
489                     "Data may be corrupted, or further writes to the image "
490                     "may corrupt it.\n",
491                     check->corruptions);
492         }
493 
494         if (check->leaks) {
495             qprintf(quiet,
496                     "\n%" PRId64 " leaked clusters were found on the image.\n"
497                     "This means waste of disk space, but no harm to data.\n",
498                     check->leaks);
499         }
500 
501         if (check->check_errors) {
502             qprintf(quiet,
503                     "\n%" PRId64
504                     " internal errors have occurred during the check.\n",
505                     check->check_errors);
506         }
507     }
508 
509     if (check->total_clusters != 0 && check->allocated_clusters != 0) {
510         qprintf(quiet, "%" PRId64 "/%" PRId64 " = %0.2f%% allocated, "
511                 "%0.2f%% fragmented, %0.2f%% compressed clusters\n",
512                 check->allocated_clusters, check->total_clusters,
513                 check->allocated_clusters * 100.0 / check->total_clusters,
514                 check->fragmented_clusters * 100.0 / check->allocated_clusters,
515                 check->compressed_clusters * 100.0 /
516                 check->allocated_clusters);
517     }
518 
519     if (check->image_end_offset) {
520         qprintf(quiet,
521                 "Image end offset: %" PRId64 "\n", check->image_end_offset);
522     }
523 }
524 
525 static int collect_image_check(BlockDriverState *bs,
526                    ImageCheck *check,
527                    const char *filename,
528                    const char *fmt,
529                    int fix)
530 {
531     int ret;
532     BdrvCheckResult result;
533 
534     ret = bdrv_check(bs, &result, fix);
535     if (ret < 0) {
536         return ret;
537     }
538 
539     check->filename                 = g_strdup(filename);
540     check->format                   = g_strdup(bdrv_get_format_name(bs));
541     check->check_errors             = result.check_errors;
542     check->corruptions              = result.corruptions;
543     check->has_corruptions          = result.corruptions != 0;
544     check->leaks                    = result.leaks;
545     check->has_leaks                = result.leaks != 0;
546     check->corruptions_fixed        = result.corruptions_fixed;
547     check->has_corruptions_fixed    = result.corruptions != 0;
548     check->leaks_fixed              = result.leaks_fixed;
549     check->has_leaks_fixed          = result.leaks != 0;
550     check->image_end_offset         = result.image_end_offset;
551     check->has_image_end_offset     = result.image_end_offset != 0;
552     check->total_clusters           = result.bfi.total_clusters;
553     check->has_total_clusters       = result.bfi.total_clusters != 0;
554     check->allocated_clusters       = result.bfi.allocated_clusters;
555     check->has_allocated_clusters   = result.bfi.allocated_clusters != 0;
556     check->fragmented_clusters      = result.bfi.fragmented_clusters;
557     check->has_fragmented_clusters  = result.bfi.fragmented_clusters != 0;
558     check->compressed_clusters      = result.bfi.compressed_clusters;
559     check->has_compressed_clusters  = result.bfi.compressed_clusters != 0;
560 
561     return 0;
562 }
563 
564 /*
565  * Checks an image for consistency. Exit codes:
566  *
567  *  0 - Check completed, image is good
568  *  1 - Check not completed because of internal errors
569  *  2 - Check completed, image is corrupted
570  *  3 - Check completed, image has leaked clusters, but is good otherwise
571  * 63 - Checks are not supported by the image format
572  */
573 static int img_check(int argc, char **argv)
574 {
575     int c, ret;
576     OutputFormat output_format = OFORMAT_HUMAN;
577     const char *filename, *fmt, *output, *cache;
578     BlockDriverState *bs;
579     int fix = 0;
580     int flags = BDRV_O_FLAGS | BDRV_O_CHECK;
581     ImageCheck *check;
582     bool quiet = false;
583 
584     fmt = NULL;
585     output = NULL;
586     cache = BDRV_DEFAULT_CACHE;
587     for(;;) {
588         int option_index = 0;
589         static const struct option long_options[] = {
590             {"help", no_argument, 0, 'h'},
591             {"format", required_argument, 0, 'f'},
592             {"repair", required_argument, 0, 'r'},
593             {"output", required_argument, 0, OPTION_OUTPUT},
594             {0, 0, 0, 0}
595         };
596         c = getopt_long(argc, argv, "hf:r:T:q",
597                         long_options, &option_index);
598         if (c == -1) {
599             break;
600         }
601         switch(c) {
602         case '?':
603         case 'h':
604             help();
605             break;
606         case 'f':
607             fmt = optarg;
608             break;
609         case 'r':
610             flags |= BDRV_O_RDWR;
611 
612             if (!strcmp(optarg, "leaks")) {
613                 fix = BDRV_FIX_LEAKS;
614             } else if (!strcmp(optarg, "all")) {
615                 fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS;
616             } else {
617                 error_exit("Unknown option value for -r "
618                            "(expecting 'leaks' or 'all'): %s", optarg);
619             }
620             break;
621         case OPTION_OUTPUT:
622             output = optarg;
623             break;
624         case 'T':
625             cache = optarg;
626             break;
627         case 'q':
628             quiet = true;
629             break;
630         }
631     }
632     if (optind != argc - 1) {
633         error_exit("Expecting one image file name");
634     }
635     filename = argv[optind++];
636 
637     if (output && !strcmp(output, "json")) {
638         output_format = OFORMAT_JSON;
639     } else if (output && !strcmp(output, "human")) {
640         output_format = OFORMAT_HUMAN;
641     } else if (output) {
642         error_report("--output must be used with human or json as argument.");
643         return 1;
644     }
645 
646     ret = bdrv_parse_cache_flags(cache, &flags);
647     if (ret < 0) {
648         error_report("Invalid source cache option: %s", cache);
649         return 1;
650     }
651 
652     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
653     if (!bs) {
654         return 1;
655     }
656 
657     check = g_new0(ImageCheck, 1);
658     ret = collect_image_check(bs, check, filename, fmt, fix);
659 
660     if (ret == -ENOTSUP) {
661         error_report("This image format does not support checks");
662         ret = 63;
663         goto fail;
664     }
665 
666     if (check->corruptions_fixed || check->leaks_fixed) {
667         int corruptions_fixed, leaks_fixed;
668 
669         leaks_fixed         = check->leaks_fixed;
670         corruptions_fixed   = check->corruptions_fixed;
671 
672         if (output_format == OFORMAT_HUMAN) {
673             qprintf(quiet,
674                     "The following inconsistencies were found and repaired:\n\n"
675                     "    %" PRId64 " leaked clusters\n"
676                     "    %" PRId64 " corruptions\n\n"
677                     "Double checking the fixed image now...\n",
678                     check->leaks_fixed,
679                     check->corruptions_fixed);
680         }
681 
682         ret = collect_image_check(bs, check, filename, fmt, 0);
683 
684         check->leaks_fixed          = leaks_fixed;
685         check->corruptions_fixed    = corruptions_fixed;
686     }
687 
688     switch (output_format) {
689     case OFORMAT_HUMAN:
690         dump_human_image_check(check, quiet);
691         break;
692     case OFORMAT_JSON:
693         dump_json_image_check(check, quiet);
694         break;
695     }
696 
697     if (ret || check->check_errors) {
698         ret = 1;
699         goto fail;
700     }
701 
702     if (check->corruptions) {
703         ret = 2;
704     } else if (check->leaks) {
705         ret = 3;
706     } else {
707         ret = 0;
708     }
709 
710 fail:
711     qapi_free_ImageCheck(check);
712     bdrv_unref(bs);
713 
714     return ret;
715 }
716 
717 static int img_commit(int argc, char **argv)
718 {
719     int c, ret, flags;
720     const char *filename, *fmt, *cache;
721     BlockDriverState *bs;
722     bool quiet = false;
723 
724     fmt = NULL;
725     cache = BDRV_DEFAULT_CACHE;
726     for(;;) {
727         c = getopt(argc, argv, "f:ht:q");
728         if (c == -1) {
729             break;
730         }
731         switch(c) {
732         case '?':
733         case 'h':
734             help();
735             break;
736         case 'f':
737             fmt = optarg;
738             break;
739         case 't':
740             cache = optarg;
741             break;
742         case 'q':
743             quiet = true;
744             break;
745         }
746     }
747     if (optind != argc - 1) {
748         error_exit("Expecting one image file name");
749     }
750     filename = argv[optind++];
751 
752     flags = BDRV_O_RDWR;
753     ret = bdrv_parse_cache_flags(cache, &flags);
754     if (ret < 0) {
755         error_report("Invalid cache option: %s", cache);
756         return 1;
757     }
758 
759     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
760     if (!bs) {
761         return 1;
762     }
763     ret = bdrv_commit(bs);
764     switch(ret) {
765     case 0:
766         qprintf(quiet, "Image committed.\n");
767         break;
768     case -ENOENT:
769         error_report("No disk inserted");
770         break;
771     case -EACCES:
772         error_report("Image is read-only");
773         break;
774     case -ENOTSUP:
775         error_report("Image is already committed");
776         break;
777     default:
778         error_report("Error while committing image");
779         break;
780     }
781 
782     bdrv_unref(bs);
783     if (ret) {
784         return 1;
785     }
786     return 0;
787 }
788 
789 /*
790  * Returns true iff the first sector pointed to by 'buf' contains at least
791  * a non-NUL byte.
792  *
793  * 'pnum' is set to the number of sectors (including and immediately following
794  * the first one) that are known to be in the same allocated/unallocated state.
795  */
796 static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)
797 {
798     bool is_zero;
799     int i;
800 
801     if (n <= 0) {
802         *pnum = 0;
803         return 0;
804     }
805     is_zero = buffer_is_zero(buf, 512);
806     for(i = 1; i < n; i++) {
807         buf += 512;
808         if (is_zero != buffer_is_zero(buf, 512)) {
809             break;
810         }
811     }
812     *pnum = i;
813     return !is_zero;
814 }
815 
816 /*
817  * Like is_allocated_sectors, but if the buffer starts with a used sector,
818  * up to 'min' consecutive sectors containing zeros are ignored. This avoids
819  * breaking up write requests for only small sparse areas.
820  */
821 static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,
822     int min)
823 {
824     int ret;
825     int num_checked, num_used;
826 
827     if (n < min) {
828         min = n;
829     }
830 
831     ret = is_allocated_sectors(buf, n, pnum);
832     if (!ret) {
833         return ret;
834     }
835 
836     num_used = *pnum;
837     buf += BDRV_SECTOR_SIZE * *pnum;
838     n -= *pnum;
839     num_checked = num_used;
840 
841     while (n > 0) {
842         ret = is_allocated_sectors(buf, n, pnum);
843 
844         buf += BDRV_SECTOR_SIZE * *pnum;
845         n -= *pnum;
846         num_checked += *pnum;
847         if (ret) {
848             num_used = num_checked;
849         } else if (*pnum >= min) {
850             break;
851         }
852     }
853 
854     *pnum = num_used;
855     return 1;
856 }
857 
858 /*
859  * Compares two buffers sector by sector. Returns 0 if the first sector of both
860  * buffers matches, non-zero otherwise.
861  *
862  * pnum is set to the number of sectors (including and immediately following
863  * the first one) that are known to have the same comparison result
864  */
865 static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
866     int *pnum)
867 {
868     int res, i;
869 
870     if (n <= 0) {
871         *pnum = 0;
872         return 0;
873     }
874 
875     res = !!memcmp(buf1, buf2, 512);
876     for(i = 1; i < n; i++) {
877         buf1 += 512;
878         buf2 += 512;
879 
880         if (!!memcmp(buf1, buf2, 512) != res) {
881             break;
882         }
883     }
884 
885     *pnum = i;
886     return res;
887 }
888 
889 #define IO_BUF_SIZE (2 * 1024 * 1024)
890 
891 static int64_t sectors_to_bytes(int64_t sectors)
892 {
893     return sectors << BDRV_SECTOR_BITS;
894 }
895 
896 static int64_t sectors_to_process(int64_t total, int64_t from)
897 {
898     return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);
899 }
900 
901 /*
902  * Check if passed sectors are empty (not allocated or contain only 0 bytes)
903  *
904  * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero
905  * data and negative value on error.
906  *
907  * @param bs:  Driver used for accessing file
908  * @param sect_num: Number of first sector to check
909  * @param sect_count: Number of sectors to check
910  * @param filename: Name of disk file we are checking (logging purpose)
911  * @param buffer: Allocated buffer for storing read data
912  * @param quiet: Flag for quiet mode
913  */
914 static int check_empty_sectors(BlockDriverState *bs, int64_t sect_num,
915                                int sect_count, const char *filename,
916                                uint8_t *buffer, bool quiet)
917 {
918     int pnum, ret = 0;
919     ret = bdrv_read(bs, sect_num, buffer, sect_count);
920     if (ret < 0) {
921         error_report("Error while reading offset %" PRId64 " of %s: %s",
922                      sectors_to_bytes(sect_num), filename, strerror(-ret));
923         return ret;
924     }
925     ret = is_allocated_sectors(buffer, sect_count, &pnum);
926     if (ret || pnum != sect_count) {
927         qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
928                 sectors_to_bytes(ret ? sect_num : sect_num + pnum));
929         return 1;
930     }
931 
932     return 0;
933 }
934 
935 /*
936  * Compares two images. Exit codes:
937  *
938  * 0 - Images are identical
939  * 1 - Images differ
940  * >1 - Error occurred
941  */
942 static int img_compare(int argc, char **argv)
943 {
944     const char *fmt1 = NULL, *fmt2 = NULL, *cache, *filename1, *filename2;
945     BlockDriverState *bs1, *bs2;
946     int64_t total_sectors1, total_sectors2;
947     uint8_t *buf1 = NULL, *buf2 = NULL;
948     int pnum1, pnum2;
949     int allocated1, allocated2;
950     int ret = 0; /* return value - 0 Ident, 1 Different, >1 Error */
951     bool progress = false, quiet = false, strict = false;
952     int flags;
953     int64_t total_sectors;
954     int64_t sector_num = 0;
955     int64_t nb_sectors;
956     int c, pnum;
957     uint64_t progress_base;
958 
959     cache = BDRV_DEFAULT_CACHE;
960     for (;;) {
961         c = getopt(argc, argv, "hf:F:T:pqs");
962         if (c == -1) {
963             break;
964         }
965         switch (c) {
966         case '?':
967         case 'h':
968             help();
969             break;
970         case 'f':
971             fmt1 = optarg;
972             break;
973         case 'F':
974             fmt2 = optarg;
975             break;
976         case 'T':
977             cache = optarg;
978             break;
979         case 'p':
980             progress = true;
981             break;
982         case 'q':
983             quiet = true;
984             break;
985         case 's':
986             strict = true;
987             break;
988         }
989     }
990 
991     /* Progress is not shown in Quiet mode */
992     if (quiet) {
993         progress = false;
994     }
995 
996 
997     if (optind != argc - 2) {
998         error_exit("Expecting two image file names");
999     }
1000     filename1 = argv[optind++];
1001     filename2 = argv[optind++];
1002 
1003     /* Initialize before goto out */
1004     qemu_progress_init(progress, 2.0);
1005 
1006     flags = BDRV_O_FLAGS;
1007     ret = bdrv_parse_cache_flags(cache, &flags);
1008     if (ret < 0) {
1009         error_report("Invalid source cache option: %s", cache);
1010         ret = 2;
1011         goto out3;
1012     }
1013 
1014     bs1 = bdrv_new_open("image 1", filename1, fmt1, flags, true, quiet);
1015     if (!bs1) {
1016         error_report("Can't open file %s", filename1);
1017         ret = 2;
1018         goto out3;
1019     }
1020 
1021     bs2 = bdrv_new_open("image 2", filename2, fmt2, flags, true, quiet);
1022     if (!bs2) {
1023         error_report("Can't open file %s", filename2);
1024         ret = 2;
1025         goto out2;
1026     }
1027 
1028     buf1 = qemu_blockalign(bs1, IO_BUF_SIZE);
1029     buf2 = qemu_blockalign(bs2, IO_BUF_SIZE);
1030     total_sectors1 = bdrv_nb_sectors(bs1);
1031     if (total_sectors1 < 0) {
1032         error_report("Can't get size of %s: %s",
1033                      filename1, strerror(-total_sectors1));
1034         ret = 4;
1035         goto out;
1036     }
1037     total_sectors2 = bdrv_nb_sectors(bs2);
1038     if (total_sectors2 < 0) {
1039         error_report("Can't get size of %s: %s",
1040                      filename2, strerror(-total_sectors2));
1041         ret = 4;
1042         goto out;
1043     }
1044     total_sectors = MIN(total_sectors1, total_sectors2);
1045     progress_base = MAX(total_sectors1, total_sectors2);
1046 
1047     qemu_progress_print(0, 100);
1048 
1049     if (strict && total_sectors1 != total_sectors2) {
1050         ret = 1;
1051         qprintf(quiet, "Strict mode: Image size mismatch!\n");
1052         goto out;
1053     }
1054 
1055     for (;;) {
1056         nb_sectors = sectors_to_process(total_sectors, sector_num);
1057         if (nb_sectors <= 0) {
1058             break;
1059         }
1060         allocated1 = bdrv_is_allocated_above(bs1, NULL, sector_num, nb_sectors,
1061                                              &pnum1);
1062         if (allocated1 < 0) {
1063             ret = 3;
1064             error_report("Sector allocation test failed for %s", filename1);
1065             goto out;
1066         }
1067 
1068         allocated2 = bdrv_is_allocated_above(bs2, NULL, sector_num, nb_sectors,
1069                                              &pnum2);
1070         if (allocated2 < 0) {
1071             ret = 3;
1072             error_report("Sector allocation test failed for %s", filename2);
1073             goto out;
1074         }
1075         nb_sectors = MIN(pnum1, pnum2);
1076 
1077         if (allocated1 == allocated2) {
1078             if (allocated1) {
1079                 ret = bdrv_read(bs1, sector_num, buf1, nb_sectors);
1080                 if (ret < 0) {
1081                     error_report("Error while reading offset %" PRId64 " of %s:"
1082                                  " %s", sectors_to_bytes(sector_num), filename1,
1083                                  strerror(-ret));
1084                     ret = 4;
1085                     goto out;
1086                 }
1087                 ret = bdrv_read(bs2, sector_num, buf2, nb_sectors);
1088                 if (ret < 0) {
1089                     error_report("Error while reading offset %" PRId64
1090                                  " of %s: %s", sectors_to_bytes(sector_num),
1091                                  filename2, strerror(-ret));
1092                     ret = 4;
1093                     goto out;
1094                 }
1095                 ret = compare_sectors(buf1, buf2, nb_sectors, &pnum);
1096                 if (ret || pnum != nb_sectors) {
1097                     qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
1098                             sectors_to_bytes(
1099                                 ret ? sector_num : sector_num + pnum));
1100                     ret = 1;
1101                     goto out;
1102                 }
1103             }
1104         } else {
1105             if (strict) {
1106                 ret = 1;
1107                 qprintf(quiet, "Strict mode: Offset %" PRId64
1108                         " allocation mismatch!\n",
1109                         sectors_to_bytes(sector_num));
1110                 goto out;
1111             }
1112 
1113             if (allocated1) {
1114                 ret = check_empty_sectors(bs1, sector_num, nb_sectors,
1115                                           filename1, buf1, quiet);
1116             } else {
1117                 ret = check_empty_sectors(bs2, sector_num, nb_sectors,
1118                                           filename2, buf1, quiet);
1119             }
1120             if (ret) {
1121                 if (ret < 0) {
1122                     error_report("Error while reading offset %" PRId64 ": %s",
1123                                  sectors_to_bytes(sector_num), strerror(-ret));
1124                     ret = 4;
1125                 }
1126                 goto out;
1127             }
1128         }
1129         sector_num += nb_sectors;
1130         qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1131     }
1132 
1133     if (total_sectors1 != total_sectors2) {
1134         BlockDriverState *bs_over;
1135         int64_t total_sectors_over;
1136         const char *filename_over;
1137 
1138         qprintf(quiet, "Warning: Image size mismatch!\n");
1139         if (total_sectors1 > total_sectors2) {
1140             total_sectors_over = total_sectors1;
1141             bs_over = bs1;
1142             filename_over = filename1;
1143         } else {
1144             total_sectors_over = total_sectors2;
1145             bs_over = bs2;
1146             filename_over = filename2;
1147         }
1148 
1149         for (;;) {
1150             nb_sectors = sectors_to_process(total_sectors_over, sector_num);
1151             if (nb_sectors <= 0) {
1152                 break;
1153             }
1154             ret = bdrv_is_allocated_above(bs_over, NULL, sector_num,
1155                                           nb_sectors, &pnum);
1156             if (ret < 0) {
1157                 ret = 3;
1158                 error_report("Sector allocation test failed for %s",
1159                              filename_over);
1160                 goto out;
1161 
1162             }
1163             nb_sectors = pnum;
1164             if (ret) {
1165                 ret = check_empty_sectors(bs_over, sector_num, nb_sectors,
1166                                           filename_over, buf1, quiet);
1167                 if (ret) {
1168                     if (ret < 0) {
1169                         error_report("Error while reading offset %" PRId64
1170                                      " of %s: %s", sectors_to_bytes(sector_num),
1171                                      filename_over, strerror(-ret));
1172                         ret = 4;
1173                     }
1174                     goto out;
1175                 }
1176             }
1177             sector_num += nb_sectors;
1178             qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1179         }
1180     }
1181 
1182     qprintf(quiet, "Images are identical.\n");
1183     ret = 0;
1184 
1185 out:
1186     bdrv_unref(bs2);
1187     qemu_vfree(buf1);
1188     qemu_vfree(buf2);
1189 out2:
1190     bdrv_unref(bs1);
1191 out3:
1192     qemu_progress_end();
1193     return ret;
1194 }
1195 
1196 static int img_convert(int argc, char **argv)
1197 {
1198     int c, n, n1, bs_n, bs_i, compress, cluster_sectors, skip_create;
1199     int64_t ret = 0;
1200     int progress = 0, flags, src_flags;
1201     const char *fmt, *out_fmt, *cache, *src_cache, *out_baseimg, *out_filename;
1202     BlockDriver *drv, *proto_drv;
1203     BlockDriverState **bs = NULL, *out_bs = NULL;
1204     int64_t total_sectors, nb_sectors, sector_num, bs_offset;
1205     int64_t *bs_sectors = NULL;
1206     uint8_t * buf = NULL;
1207     size_t bufsectors = IO_BUF_SIZE / BDRV_SECTOR_SIZE;
1208     const uint8_t *buf1;
1209     BlockDriverInfo bdi;
1210     QemuOpts *opts = NULL;
1211     QemuOptsList *create_opts = NULL;
1212     const char *out_baseimg_param;
1213     char *options = NULL;
1214     const char *snapshot_name = NULL;
1215     int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */
1216     bool quiet = false;
1217     Error *local_err = NULL;
1218     QemuOpts *sn_opts = NULL;
1219 
1220     fmt = NULL;
1221     out_fmt = "raw";
1222     cache = "unsafe";
1223     src_cache = BDRV_DEFAULT_CACHE;
1224     out_baseimg = NULL;
1225     compress = 0;
1226     skip_create = 0;
1227     for(;;) {
1228         c = getopt(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qn");
1229         if (c == -1) {
1230             break;
1231         }
1232         switch(c) {
1233         case '?':
1234         case 'h':
1235             help();
1236             break;
1237         case 'f':
1238             fmt = optarg;
1239             break;
1240         case 'O':
1241             out_fmt = optarg;
1242             break;
1243         case 'B':
1244             out_baseimg = optarg;
1245             break;
1246         case 'c':
1247             compress = 1;
1248             break;
1249         case 'e':
1250             error_report("option -e is deprecated, please use \'-o "
1251                   "encryption\' instead!");
1252             ret = -1;
1253             goto fail_getopt;
1254         case '6':
1255             error_report("option -6 is deprecated, please use \'-o "
1256                   "compat6\' instead!");
1257             ret = -1;
1258             goto fail_getopt;
1259         case 'o':
1260             if (!is_valid_option_list(optarg)) {
1261                 error_report("Invalid option list: %s", optarg);
1262                 ret = -1;
1263                 goto fail_getopt;
1264             }
1265             if (!options) {
1266                 options = g_strdup(optarg);
1267             } else {
1268                 char *old_options = options;
1269                 options = g_strdup_printf("%s,%s", options, optarg);
1270                 g_free(old_options);
1271             }
1272             break;
1273         case 's':
1274             snapshot_name = optarg;
1275             break;
1276         case 'l':
1277             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
1278                 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0);
1279                 if (!sn_opts) {
1280                     error_report("Failed in parsing snapshot param '%s'",
1281                                  optarg);
1282                     ret = -1;
1283                     goto fail_getopt;
1284                 }
1285             } else {
1286                 snapshot_name = optarg;
1287             }
1288             break;
1289         case 'S':
1290         {
1291             int64_t sval;
1292             char *end;
1293             sval = strtosz_suffix(optarg, &end, STRTOSZ_DEFSUFFIX_B);
1294             if (sval < 0 || *end) {
1295                 error_report("Invalid minimum zero buffer size for sparse output specified");
1296                 ret = -1;
1297                 goto fail_getopt;
1298             }
1299 
1300             min_sparse = sval / BDRV_SECTOR_SIZE;
1301             break;
1302         }
1303         case 'p':
1304             progress = 1;
1305             break;
1306         case 't':
1307             cache = optarg;
1308             break;
1309         case 'T':
1310             src_cache = optarg;
1311             break;
1312         case 'q':
1313             quiet = true;
1314             break;
1315         case 'n':
1316             skip_create = 1;
1317             break;
1318         }
1319     }
1320 
1321     /* Initialize before goto out */
1322     if (quiet) {
1323         progress = 0;
1324     }
1325     qemu_progress_init(progress, 1.0);
1326 
1327 
1328     bs_n = argc - optind - 1;
1329     out_filename = bs_n >= 1 ? argv[argc - 1] : NULL;
1330 
1331     if (options && has_help_option(options)) {
1332         ret = print_block_option_help(out_filename, out_fmt);
1333         goto out;
1334     }
1335 
1336     if (bs_n < 1) {
1337         error_exit("Must specify image file name");
1338     }
1339 
1340 
1341     if (bs_n > 1 && out_baseimg) {
1342         error_report("-B makes no sense when concatenating multiple input "
1343                      "images");
1344         ret = -1;
1345         goto out;
1346     }
1347 
1348     src_flags = BDRV_O_FLAGS;
1349     ret = bdrv_parse_cache_flags(src_cache, &src_flags);
1350     if (ret < 0) {
1351         error_report("Invalid source cache option: %s", src_cache);
1352         goto out;
1353     }
1354 
1355     qemu_progress_print(0, 100);
1356 
1357     bs = g_new0(BlockDriverState *, bs_n);
1358     bs_sectors = g_new(int64_t, bs_n);
1359 
1360     total_sectors = 0;
1361     for (bs_i = 0; bs_i < bs_n; bs_i++) {
1362         char *id = bs_n > 1 ? g_strdup_printf("source %d", bs_i)
1363                             : g_strdup("source");
1364         bs[bs_i] = bdrv_new_open(id, argv[optind + bs_i], fmt, src_flags,
1365                                  true, quiet);
1366         g_free(id);
1367         if (!bs[bs_i]) {
1368             error_report("Could not open '%s'", argv[optind + bs_i]);
1369             ret = -1;
1370             goto out;
1371         }
1372         bs_sectors[bs_i] = bdrv_nb_sectors(bs[bs_i]);
1373         if (bs_sectors[bs_i] < 0) {
1374             error_report("Could not get size of %s: %s",
1375                          argv[optind + bs_i], strerror(-bs_sectors[bs_i]));
1376             ret = -1;
1377             goto out;
1378         }
1379         total_sectors += bs_sectors[bs_i];
1380     }
1381 
1382     if (sn_opts) {
1383         ret = bdrv_snapshot_load_tmp(bs[0],
1384                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1385                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1386                                      &local_err);
1387     } else if (snapshot_name != NULL) {
1388         if (bs_n > 1) {
1389             error_report("No support for concatenating multiple snapshot");
1390             ret = -1;
1391             goto out;
1392         }
1393 
1394         bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err);
1395     }
1396     if (local_err) {
1397         error_report("Failed to load snapshot: %s",
1398                      error_get_pretty(local_err));
1399         error_free(local_err);
1400         ret = -1;
1401         goto out;
1402     }
1403 
1404     /* Find driver and parse its options */
1405     drv = bdrv_find_format(out_fmt);
1406     if (!drv) {
1407         error_report("Unknown file format '%s'", out_fmt);
1408         ret = -1;
1409         goto out;
1410     }
1411 
1412     proto_drv = bdrv_find_protocol(out_filename, true);
1413     if (!proto_drv) {
1414         error_report("Unknown protocol '%s'", out_filename);
1415         ret = -1;
1416         goto out;
1417     }
1418 
1419     create_opts = qemu_opts_append(create_opts, drv->create_opts);
1420     create_opts = qemu_opts_append(create_opts, proto_drv->create_opts);
1421 
1422     opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
1423     if (options && qemu_opts_do_parse(opts, options, NULL)) {
1424         error_report("Invalid options for file format '%s'", out_fmt);
1425         ret = -1;
1426         goto out;
1427     }
1428 
1429     qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_sectors * 512);
1430     ret = add_old_style_options(out_fmt, opts, out_baseimg, NULL);
1431     if (ret < 0) {
1432         goto out;
1433     }
1434 
1435     /* Get backing file name if -o backing_file was used */
1436     out_baseimg_param = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE);
1437     if (out_baseimg_param) {
1438         out_baseimg = out_baseimg_param;
1439     }
1440 
1441     /* Check if compression is supported */
1442     if (compress) {
1443         bool encryption =
1444             qemu_opt_get_bool(opts, BLOCK_OPT_ENCRYPT, false);
1445         const char *preallocation =
1446             qemu_opt_get(opts, BLOCK_OPT_PREALLOC);
1447 
1448         if (!drv->bdrv_write_compressed) {
1449             error_report("Compression not supported for this file format");
1450             ret = -1;
1451             goto out;
1452         }
1453 
1454         if (encryption) {
1455             error_report("Compression and encryption not supported at "
1456                          "the same time");
1457             ret = -1;
1458             goto out;
1459         }
1460 
1461         if (preallocation
1462             && strcmp(preallocation, "off"))
1463         {
1464             error_report("Compression and preallocation not supported at "
1465                          "the same time");
1466             ret = -1;
1467             goto out;
1468         }
1469     }
1470 
1471     if (!skip_create) {
1472         /* Create the new image */
1473         ret = bdrv_create(drv, out_filename, opts, &local_err);
1474         if (ret < 0) {
1475             error_report("%s: error while converting %s: %s",
1476                          out_filename, out_fmt, error_get_pretty(local_err));
1477             error_free(local_err);
1478             goto out;
1479         }
1480     }
1481 
1482     flags = min_sparse ? (BDRV_O_RDWR | BDRV_O_UNMAP) : BDRV_O_RDWR;
1483     ret = bdrv_parse_cache_flags(cache, &flags);
1484     if (ret < 0) {
1485         error_report("Invalid cache option: %s", cache);
1486         goto out;
1487     }
1488 
1489     out_bs = bdrv_new_open("target", out_filename, out_fmt, flags, true, quiet);
1490     if (!out_bs) {
1491         ret = -1;
1492         goto out;
1493     }
1494 
1495     bs_i = 0;
1496     bs_offset = 0;
1497 
1498     /* increase bufsectors from the default 4096 (2M) if opt_transfer_length
1499      * or discard_alignment of the out_bs is greater. Limit to 32768 (16MB)
1500      * as maximum. */
1501     bufsectors = MIN(32768,
1502                      MAX(bufsectors, MAX(out_bs->bl.opt_transfer_length,
1503                                          out_bs->bl.discard_alignment))
1504                     );
1505 
1506     buf = qemu_blockalign(out_bs, bufsectors * BDRV_SECTOR_SIZE);
1507 
1508     if (skip_create) {
1509         int64_t output_sectors = bdrv_nb_sectors(out_bs);
1510         if (output_sectors < 0) {
1511             error_report("unable to get output image length: %s\n",
1512                          strerror(-output_sectors));
1513             ret = -1;
1514             goto out;
1515         } else if (output_sectors < total_sectors) {
1516             error_report("output file is smaller than input file");
1517             ret = -1;
1518             goto out;
1519         }
1520     }
1521 
1522     cluster_sectors = 0;
1523     ret = bdrv_get_info(out_bs, &bdi);
1524     if (ret < 0) {
1525         if (compress) {
1526             error_report("could not get block driver info");
1527             goto out;
1528         }
1529     } else {
1530         compress = compress || bdi.needs_compressed_writes;
1531         cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE;
1532     }
1533 
1534     if (compress) {
1535         if (cluster_sectors <= 0 || cluster_sectors > bufsectors) {
1536             error_report("invalid cluster size");
1537             ret = -1;
1538             goto out;
1539         }
1540         sector_num = 0;
1541 
1542         nb_sectors = total_sectors;
1543 
1544         for(;;) {
1545             int64_t bs_num;
1546             int remainder;
1547             uint8_t *buf2;
1548 
1549             nb_sectors = total_sectors - sector_num;
1550             if (nb_sectors <= 0)
1551                 break;
1552             if (nb_sectors >= cluster_sectors)
1553                 n = cluster_sectors;
1554             else
1555                 n = nb_sectors;
1556 
1557             bs_num = sector_num - bs_offset;
1558             assert (bs_num >= 0);
1559             remainder = n;
1560             buf2 = buf;
1561             while (remainder > 0) {
1562                 int nlow;
1563                 while (bs_num == bs_sectors[bs_i]) {
1564                     bs_offset += bs_sectors[bs_i];
1565                     bs_i++;
1566                     assert (bs_i < bs_n);
1567                     bs_num = 0;
1568                     /* printf("changing part: sector_num=%" PRId64 ", "
1569                        "bs_i=%d, bs_offset=%" PRId64 ", bs_sectors=%" PRId64
1570                        "\n", sector_num, bs_i, bs_offset, bs_sectors[bs_i]); */
1571                 }
1572                 assert (bs_num < bs_sectors[bs_i]);
1573 
1574                 nlow = remainder > bs_sectors[bs_i] - bs_num
1575                     ? bs_sectors[bs_i] - bs_num : remainder;
1576 
1577                 ret = bdrv_read(bs[bs_i], bs_num, buf2, nlow);
1578                 if (ret < 0) {
1579                     error_report("error while reading sector %" PRId64 ": %s",
1580                                  bs_num, strerror(-ret));
1581                     goto out;
1582                 }
1583 
1584                 buf2 += nlow * 512;
1585                 bs_num += nlow;
1586 
1587                 remainder -= nlow;
1588             }
1589             assert (remainder == 0);
1590 
1591             if (!buffer_is_zero(buf, n * BDRV_SECTOR_SIZE)) {
1592                 ret = bdrv_write_compressed(out_bs, sector_num, buf, n);
1593                 if (ret != 0) {
1594                     error_report("error while compressing sector %" PRId64
1595                                  ": %s", sector_num, strerror(-ret));
1596                     goto out;
1597                 }
1598             }
1599             sector_num += n;
1600             qemu_progress_print(100.0 * sector_num / total_sectors, 0);
1601         }
1602         /* signal EOF to align */
1603         bdrv_write_compressed(out_bs, 0, NULL, 0);
1604     } else {
1605         int64_t sectors_to_read, sectors_read, sector_num_next_status;
1606         bool count_allocated_sectors;
1607         int has_zero_init = min_sparse ? bdrv_has_zero_init(out_bs) : 0;
1608 
1609         if (!has_zero_init && bdrv_can_write_zeroes_with_unmap(out_bs)) {
1610             ret = bdrv_make_zero(out_bs, BDRV_REQ_MAY_UNMAP);
1611             if (ret < 0) {
1612                 goto out;
1613             }
1614             has_zero_init = 1;
1615         }
1616 
1617         sectors_to_read = total_sectors;
1618         count_allocated_sectors = progress && (out_baseimg || has_zero_init);
1619 restart:
1620         sector_num = 0; // total number of sectors converted so far
1621         sectors_read = 0;
1622         sector_num_next_status = 0;
1623 
1624         for(;;) {
1625             nb_sectors = total_sectors - sector_num;
1626             if (nb_sectors <= 0) {
1627                 if (count_allocated_sectors) {
1628                     sectors_to_read = sectors_read;
1629                     count_allocated_sectors = false;
1630                     goto restart;
1631                 }
1632                 ret = 0;
1633                 break;
1634             }
1635 
1636             while (sector_num - bs_offset >= bs_sectors[bs_i]) {
1637                 bs_offset += bs_sectors[bs_i];
1638                 bs_i ++;
1639                 assert (bs_i < bs_n);
1640                 /* printf("changing part: sector_num=%" PRId64 ", bs_i=%d, "
1641                   "bs_offset=%" PRId64 ", bs_sectors=%" PRId64 "\n",
1642                    sector_num, bs_i, bs_offset, bs_sectors[bs_i]); */
1643             }
1644 
1645             if ((out_baseimg || has_zero_init) &&
1646                 sector_num >= sector_num_next_status) {
1647                 n = nb_sectors > INT_MAX ? INT_MAX : nb_sectors;
1648                 ret = bdrv_get_block_status(bs[bs_i], sector_num - bs_offset,
1649                                             n, &n1);
1650                 if (ret < 0) {
1651                     error_report("error while reading block status of sector %"
1652                                  PRId64 ": %s", sector_num - bs_offset,
1653                                  strerror(-ret));
1654                     goto out;
1655                 }
1656                 /* If the output image is zero initialized, we are not working
1657                  * on a shared base and the input is zero we can skip the next
1658                  * n1 sectors */
1659                 if (has_zero_init && !out_baseimg && (ret & BDRV_BLOCK_ZERO)) {
1660                     sector_num += n1;
1661                     continue;
1662                 }
1663                 /* If the output image is being created as a copy on write
1664                  * image, assume that sectors which are unallocated in the
1665                  * input image are present in both the output's and input's
1666                  * base images (no need to copy them). */
1667                 if (out_baseimg) {
1668                     if (!(ret & BDRV_BLOCK_DATA)) {
1669                         sector_num += n1;
1670                         continue;
1671                     }
1672                     /* The next 'n1' sectors are allocated in the input image.
1673                      * Copy only those as they may be followed by unallocated
1674                      * sectors. */
1675                     nb_sectors = n1;
1676                 }
1677                 /* avoid redundant callouts to get_block_status */
1678                 sector_num_next_status = sector_num + n1;
1679             }
1680 
1681             n = MIN(nb_sectors, bufsectors);
1682 
1683             /* round down request length to an aligned sector, but
1684              * do not bother doing this on short requests. They happen
1685              * when we found an all-zero area, and the next sector to
1686              * write will not be sector_num + n. */
1687             if (cluster_sectors > 0 && n >= cluster_sectors) {
1688                 int64_t next_aligned_sector = (sector_num + n);
1689                 next_aligned_sector -= next_aligned_sector % cluster_sectors;
1690                 if (sector_num + n > next_aligned_sector) {
1691                     n = next_aligned_sector - sector_num;
1692                 }
1693             }
1694 
1695             n = MIN(n, bs_sectors[bs_i] - (sector_num - bs_offset));
1696 
1697             sectors_read += n;
1698             if (count_allocated_sectors) {
1699                 sector_num += n;
1700                 continue;
1701             }
1702 
1703             n1 = n;
1704             ret = bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n);
1705             if (ret < 0) {
1706                 error_report("error while reading sector %" PRId64 ": %s",
1707                              sector_num - bs_offset, strerror(-ret));
1708                 goto out;
1709             }
1710             /* NOTE: at the same time we convert, we do not write zero
1711                sectors to have a chance to compress the image. Ideally, we
1712                should add a specific call to have the info to go faster */
1713             buf1 = buf;
1714             while (n > 0) {
1715                 if (!has_zero_init ||
1716                     is_allocated_sectors_min(buf1, n, &n1, min_sparse)) {
1717                     ret = bdrv_write(out_bs, sector_num, buf1, n1);
1718                     if (ret < 0) {
1719                         error_report("error while writing sector %" PRId64
1720                                      ": %s", sector_num, strerror(-ret));
1721                         goto out;
1722                     }
1723                 }
1724                 sector_num += n1;
1725                 n -= n1;
1726                 buf1 += n1 * 512;
1727             }
1728             qemu_progress_print(100.0 * sectors_read / sectors_to_read, 0);
1729         }
1730     }
1731 out:
1732     if (!ret) {
1733         qemu_progress_print(100, 0);
1734     }
1735     qemu_progress_end();
1736     qemu_opts_del(opts);
1737     qemu_opts_free(create_opts);
1738     qemu_vfree(buf);
1739     if (sn_opts) {
1740         qemu_opts_del(sn_opts);
1741     }
1742     if (out_bs) {
1743         bdrv_unref(out_bs);
1744     }
1745     if (bs) {
1746         for (bs_i = 0; bs_i < bs_n; bs_i++) {
1747             if (bs[bs_i]) {
1748                 bdrv_unref(bs[bs_i]);
1749             }
1750         }
1751         g_free(bs);
1752     }
1753     g_free(bs_sectors);
1754 fail_getopt:
1755     g_free(options);
1756 
1757     if (ret) {
1758         return 1;
1759     }
1760     return 0;
1761 }
1762 
1763 
1764 static void dump_snapshots(BlockDriverState *bs)
1765 {
1766     QEMUSnapshotInfo *sn_tab, *sn;
1767     int nb_sns, i;
1768 
1769     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1770     if (nb_sns <= 0)
1771         return;
1772     printf("Snapshot list:\n");
1773     bdrv_snapshot_dump(fprintf, stdout, NULL);
1774     printf("\n");
1775     for(i = 0; i < nb_sns; i++) {
1776         sn = &sn_tab[i];
1777         bdrv_snapshot_dump(fprintf, stdout, sn);
1778         printf("\n");
1779     }
1780     g_free(sn_tab);
1781 }
1782 
1783 static void dump_json_image_info_list(ImageInfoList *list)
1784 {
1785     Error *local_err = NULL;
1786     QString *str;
1787     QmpOutputVisitor *ov = qmp_output_visitor_new();
1788     QObject *obj;
1789     visit_type_ImageInfoList(qmp_output_get_visitor(ov),
1790                              &list, NULL, &local_err);
1791     obj = qmp_output_get_qobject(ov);
1792     str = qobject_to_json_pretty(obj);
1793     assert(str != NULL);
1794     printf("%s\n", qstring_get_str(str));
1795     qobject_decref(obj);
1796     qmp_output_visitor_cleanup(ov);
1797     QDECREF(str);
1798 }
1799 
1800 static void dump_json_image_info(ImageInfo *info)
1801 {
1802     Error *local_err = NULL;
1803     QString *str;
1804     QmpOutputVisitor *ov = qmp_output_visitor_new();
1805     QObject *obj;
1806     visit_type_ImageInfo(qmp_output_get_visitor(ov),
1807                          &info, NULL, &local_err);
1808     obj = qmp_output_get_qobject(ov);
1809     str = qobject_to_json_pretty(obj);
1810     assert(str != NULL);
1811     printf("%s\n", qstring_get_str(str));
1812     qobject_decref(obj);
1813     qmp_output_visitor_cleanup(ov);
1814     QDECREF(str);
1815 }
1816 
1817 static void dump_human_image_info_list(ImageInfoList *list)
1818 {
1819     ImageInfoList *elem;
1820     bool delim = false;
1821 
1822     for (elem = list; elem; elem = elem->next) {
1823         if (delim) {
1824             printf("\n");
1825         }
1826         delim = true;
1827 
1828         bdrv_image_info_dump(fprintf, stdout, elem->value);
1829     }
1830 }
1831 
1832 static gboolean str_equal_func(gconstpointer a, gconstpointer b)
1833 {
1834     return strcmp(a, b) == 0;
1835 }
1836 
1837 /**
1838  * Open an image file chain and return an ImageInfoList
1839  *
1840  * @filename: topmost image filename
1841  * @fmt: topmost image format (may be NULL to autodetect)
1842  * @chain: true  - enumerate entire backing file chain
1843  *         false - only topmost image file
1844  *
1845  * Returns a list of ImageInfo objects or NULL if there was an error opening an
1846  * image file.  If there was an error a message will have been printed to
1847  * stderr.
1848  */
1849 static ImageInfoList *collect_image_info_list(const char *filename,
1850                                               const char *fmt,
1851                                               bool chain)
1852 {
1853     ImageInfoList *head = NULL;
1854     ImageInfoList **last = &head;
1855     GHashTable *filenames;
1856     Error *err = NULL;
1857 
1858     filenames = g_hash_table_new_full(g_str_hash, str_equal_func, NULL, NULL);
1859 
1860     while (filename) {
1861         BlockDriverState *bs;
1862         ImageInfo *info;
1863         ImageInfoList *elem;
1864 
1865         if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
1866             error_report("Backing file '%s' creates an infinite loop.",
1867                          filename);
1868             goto err;
1869         }
1870         g_hash_table_insert(filenames, (gpointer)filename, NULL);
1871 
1872         bs = bdrv_new_open("image", filename, fmt,
1873                            BDRV_O_FLAGS | BDRV_O_NO_BACKING, false, false);
1874         if (!bs) {
1875             goto err;
1876         }
1877 
1878         bdrv_query_image_info(bs, &info, &err);
1879         if (err) {
1880             error_report("%s", error_get_pretty(err));
1881             error_free(err);
1882             bdrv_unref(bs);
1883             goto err;
1884         }
1885 
1886         elem = g_new0(ImageInfoList, 1);
1887         elem->value = info;
1888         *last = elem;
1889         last = &elem->next;
1890 
1891         bdrv_unref(bs);
1892 
1893         filename = fmt = NULL;
1894         if (chain) {
1895             if (info->has_full_backing_filename) {
1896                 filename = info->full_backing_filename;
1897             } else if (info->has_backing_filename) {
1898                 filename = info->backing_filename;
1899             }
1900             if (info->has_backing_filename_format) {
1901                 fmt = info->backing_filename_format;
1902             }
1903         }
1904     }
1905     g_hash_table_destroy(filenames);
1906     return head;
1907 
1908 err:
1909     qapi_free_ImageInfoList(head);
1910     g_hash_table_destroy(filenames);
1911     return NULL;
1912 }
1913 
1914 static int img_info(int argc, char **argv)
1915 {
1916     int c;
1917     OutputFormat output_format = OFORMAT_HUMAN;
1918     bool chain = false;
1919     const char *filename, *fmt, *output;
1920     ImageInfoList *list;
1921 
1922     fmt = NULL;
1923     output = NULL;
1924     for(;;) {
1925         int option_index = 0;
1926         static const struct option long_options[] = {
1927             {"help", no_argument, 0, 'h'},
1928             {"format", required_argument, 0, 'f'},
1929             {"output", required_argument, 0, OPTION_OUTPUT},
1930             {"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
1931             {0, 0, 0, 0}
1932         };
1933         c = getopt_long(argc, argv, "f:h",
1934                         long_options, &option_index);
1935         if (c == -1) {
1936             break;
1937         }
1938         switch(c) {
1939         case '?':
1940         case 'h':
1941             help();
1942             break;
1943         case 'f':
1944             fmt = optarg;
1945             break;
1946         case OPTION_OUTPUT:
1947             output = optarg;
1948             break;
1949         case OPTION_BACKING_CHAIN:
1950             chain = true;
1951             break;
1952         }
1953     }
1954     if (optind != argc - 1) {
1955         error_exit("Expecting one image file name");
1956     }
1957     filename = argv[optind++];
1958 
1959     if (output && !strcmp(output, "json")) {
1960         output_format = OFORMAT_JSON;
1961     } else if (output && !strcmp(output, "human")) {
1962         output_format = OFORMAT_HUMAN;
1963     } else if (output) {
1964         error_report("--output must be used with human or json as argument.");
1965         return 1;
1966     }
1967 
1968     list = collect_image_info_list(filename, fmt, chain);
1969     if (!list) {
1970         return 1;
1971     }
1972 
1973     switch (output_format) {
1974     case OFORMAT_HUMAN:
1975         dump_human_image_info_list(list);
1976         break;
1977     case OFORMAT_JSON:
1978         if (chain) {
1979             dump_json_image_info_list(list);
1980         } else {
1981             dump_json_image_info(list->value);
1982         }
1983         break;
1984     }
1985 
1986     qapi_free_ImageInfoList(list);
1987     return 0;
1988 }
1989 
1990 
1991 typedef struct MapEntry {
1992     int flags;
1993     int depth;
1994     int64_t start;
1995     int64_t length;
1996     int64_t offset;
1997     BlockDriverState *bs;
1998 } MapEntry;
1999 
2000 static void dump_map_entry(OutputFormat output_format, MapEntry *e,
2001                            MapEntry *next)
2002 {
2003     switch (output_format) {
2004     case OFORMAT_HUMAN:
2005         if ((e->flags & BDRV_BLOCK_DATA) &&
2006             !(e->flags & BDRV_BLOCK_OFFSET_VALID)) {
2007             error_report("File contains external, encrypted or compressed clusters.");
2008             exit(1);
2009         }
2010         if ((e->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) == BDRV_BLOCK_DATA) {
2011             printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
2012                    e->start, e->length, e->offset, e->bs->filename);
2013         }
2014         /* This format ignores the distinction between 0, ZERO and ZERO|DATA.
2015          * Modify the flags here to allow more coalescing.
2016          */
2017         if (next &&
2018             (next->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) != BDRV_BLOCK_DATA) {
2019             next->flags &= ~BDRV_BLOCK_DATA;
2020             next->flags |= BDRV_BLOCK_ZERO;
2021         }
2022         break;
2023     case OFORMAT_JSON:
2024         printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64", \"depth\": %d,"
2025                " \"zero\": %s, \"data\": %s",
2026                (e->start == 0 ? "[" : ",\n"),
2027                e->start, e->length, e->depth,
2028                (e->flags & BDRV_BLOCK_ZERO) ? "true" : "false",
2029                (e->flags & BDRV_BLOCK_DATA) ? "true" : "false");
2030         if (e->flags & BDRV_BLOCK_OFFSET_VALID) {
2031             printf(", \"offset\": %"PRId64"", e->offset);
2032         }
2033         putchar('}');
2034 
2035         if (!next) {
2036             printf("]\n");
2037         }
2038         break;
2039     }
2040 }
2041 
2042 static int get_block_status(BlockDriverState *bs, int64_t sector_num,
2043                             int nb_sectors, MapEntry *e)
2044 {
2045     int64_t ret;
2046     int depth;
2047 
2048     /* As an optimization, we could cache the current range of unallocated
2049      * clusters in each file of the chain, and avoid querying the same
2050      * range repeatedly.
2051      */
2052 
2053     depth = 0;
2054     for (;;) {
2055         ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors);
2056         if (ret < 0) {
2057             return ret;
2058         }
2059         assert(nb_sectors);
2060         if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
2061             break;
2062         }
2063         bs = bs->backing_hd;
2064         if (bs == NULL) {
2065             ret = 0;
2066             break;
2067         }
2068 
2069         depth++;
2070     }
2071 
2072     e->start = sector_num * BDRV_SECTOR_SIZE;
2073     e->length = nb_sectors * BDRV_SECTOR_SIZE;
2074     e->flags = ret & ~BDRV_BLOCK_OFFSET_MASK;
2075     e->offset = ret & BDRV_BLOCK_OFFSET_MASK;
2076     e->depth = depth;
2077     e->bs = bs;
2078     return 0;
2079 }
2080 
2081 static int img_map(int argc, char **argv)
2082 {
2083     int c;
2084     OutputFormat output_format = OFORMAT_HUMAN;
2085     BlockDriverState *bs;
2086     const char *filename, *fmt, *output;
2087     int64_t length;
2088     MapEntry curr = { .length = 0 }, next;
2089     int ret = 0;
2090 
2091     fmt = NULL;
2092     output = NULL;
2093     for (;;) {
2094         int option_index = 0;
2095         static const struct option long_options[] = {
2096             {"help", no_argument, 0, 'h'},
2097             {"format", required_argument, 0, 'f'},
2098             {"output", required_argument, 0, OPTION_OUTPUT},
2099             {0, 0, 0, 0}
2100         };
2101         c = getopt_long(argc, argv, "f:h",
2102                         long_options, &option_index);
2103         if (c == -1) {
2104             break;
2105         }
2106         switch (c) {
2107         case '?':
2108         case 'h':
2109             help();
2110             break;
2111         case 'f':
2112             fmt = optarg;
2113             break;
2114         case OPTION_OUTPUT:
2115             output = optarg;
2116             break;
2117         }
2118     }
2119     if (optind != argc - 1) {
2120         error_exit("Expecting one image file name");
2121     }
2122     filename = argv[optind];
2123 
2124     if (output && !strcmp(output, "json")) {
2125         output_format = OFORMAT_JSON;
2126     } else if (output && !strcmp(output, "human")) {
2127         output_format = OFORMAT_HUMAN;
2128     } else if (output) {
2129         error_report("--output must be used with human or json as argument.");
2130         return 1;
2131     }
2132 
2133     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS, true, false);
2134     if (!bs) {
2135         return 1;
2136     }
2137 
2138     if (output_format == OFORMAT_HUMAN) {
2139         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
2140     }
2141 
2142     length = bdrv_getlength(bs);
2143     while (curr.start + curr.length < length) {
2144         int64_t nsectors_left;
2145         int64_t sector_num;
2146         int n;
2147 
2148         sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
2149 
2150         /* Probe up to 1 GiB at a time.  */
2151         nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
2152         n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
2153         ret = get_block_status(bs, sector_num, n, &next);
2154 
2155         if (ret < 0) {
2156             error_report("Could not read file metadata: %s", strerror(-ret));
2157             goto out;
2158         }
2159 
2160         if (curr.length != 0 && curr.flags == next.flags &&
2161             curr.depth == next.depth &&
2162             ((curr.flags & BDRV_BLOCK_OFFSET_VALID) == 0 ||
2163              curr.offset + curr.length == next.offset)) {
2164             curr.length += next.length;
2165             continue;
2166         }
2167 
2168         if (curr.length > 0) {
2169             dump_map_entry(output_format, &curr, &next);
2170         }
2171         curr = next;
2172     }
2173 
2174     dump_map_entry(output_format, &curr, NULL);
2175 
2176 out:
2177     bdrv_unref(bs);
2178     return ret < 0;
2179 }
2180 
2181 #define SNAPSHOT_LIST   1
2182 #define SNAPSHOT_CREATE 2
2183 #define SNAPSHOT_APPLY  3
2184 #define SNAPSHOT_DELETE 4
2185 
2186 static int img_snapshot(int argc, char **argv)
2187 {
2188     BlockDriverState *bs;
2189     QEMUSnapshotInfo sn;
2190     char *filename, *snapshot_name = NULL;
2191     int c, ret = 0, bdrv_oflags;
2192     int action = 0;
2193     qemu_timeval tv;
2194     bool quiet = false;
2195     Error *err = NULL;
2196 
2197     bdrv_oflags = BDRV_O_FLAGS | BDRV_O_RDWR;
2198     /* Parse commandline parameters */
2199     for(;;) {
2200         c = getopt(argc, argv, "la:c:d:hq");
2201         if (c == -1) {
2202             break;
2203         }
2204         switch(c) {
2205         case '?':
2206         case 'h':
2207             help();
2208             return 0;
2209         case 'l':
2210             if (action) {
2211                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2212                 return 0;
2213             }
2214             action = SNAPSHOT_LIST;
2215             bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */
2216             break;
2217         case 'a':
2218             if (action) {
2219                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2220                 return 0;
2221             }
2222             action = SNAPSHOT_APPLY;
2223             snapshot_name = optarg;
2224             break;
2225         case 'c':
2226             if (action) {
2227                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2228                 return 0;
2229             }
2230             action = SNAPSHOT_CREATE;
2231             snapshot_name = optarg;
2232             break;
2233         case 'd':
2234             if (action) {
2235                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2236                 return 0;
2237             }
2238             action = SNAPSHOT_DELETE;
2239             snapshot_name = optarg;
2240             break;
2241         case 'q':
2242             quiet = true;
2243             break;
2244         }
2245     }
2246 
2247     if (optind != argc - 1) {
2248         error_exit("Expecting one image file name");
2249     }
2250     filename = argv[optind++];
2251 
2252     /* Open the image */
2253     bs = bdrv_new_open("image", filename, NULL, bdrv_oflags, true, quiet);
2254     if (!bs) {
2255         return 1;
2256     }
2257 
2258     /* Perform the requested action */
2259     switch(action) {
2260     case SNAPSHOT_LIST:
2261         dump_snapshots(bs);
2262         break;
2263 
2264     case SNAPSHOT_CREATE:
2265         memset(&sn, 0, sizeof(sn));
2266         pstrcpy(sn.name, sizeof(sn.name), snapshot_name);
2267 
2268         qemu_gettimeofday(&tv);
2269         sn.date_sec = tv.tv_sec;
2270         sn.date_nsec = tv.tv_usec * 1000;
2271 
2272         ret = bdrv_snapshot_create(bs, &sn);
2273         if (ret) {
2274             error_report("Could not create snapshot '%s': %d (%s)",
2275                 snapshot_name, ret, strerror(-ret));
2276         }
2277         break;
2278 
2279     case SNAPSHOT_APPLY:
2280         ret = bdrv_snapshot_goto(bs, snapshot_name);
2281         if (ret) {
2282             error_report("Could not apply snapshot '%s': %d (%s)",
2283                 snapshot_name, ret, strerror(-ret));
2284         }
2285         break;
2286 
2287     case SNAPSHOT_DELETE:
2288         bdrv_snapshot_delete_by_id_or_name(bs, snapshot_name, &err);
2289         if (err) {
2290             error_report("Could not delete snapshot '%s': (%s)",
2291                          snapshot_name, error_get_pretty(err));
2292             error_free(err);
2293             ret = 1;
2294         }
2295         break;
2296     }
2297 
2298     /* Cleanup */
2299     bdrv_unref(bs);
2300     if (ret) {
2301         return 1;
2302     }
2303     return 0;
2304 }
2305 
2306 static int img_rebase(int argc, char **argv)
2307 {
2308     BlockDriverState *bs = NULL, *bs_old_backing = NULL, *bs_new_backing = NULL;
2309     BlockDriver *old_backing_drv, *new_backing_drv;
2310     char *filename;
2311     const char *fmt, *cache, *src_cache, *out_basefmt, *out_baseimg;
2312     int c, flags, src_flags, ret;
2313     int unsafe = 0;
2314     int progress = 0;
2315     bool quiet = false;
2316     Error *local_err = NULL;
2317 
2318     /* Parse commandline parameters */
2319     fmt = NULL;
2320     cache = BDRV_DEFAULT_CACHE;
2321     src_cache = BDRV_DEFAULT_CACHE;
2322     out_baseimg = NULL;
2323     out_basefmt = NULL;
2324     for(;;) {
2325         c = getopt(argc, argv, "hf:F:b:upt:T:q");
2326         if (c == -1) {
2327             break;
2328         }
2329         switch(c) {
2330         case '?':
2331         case 'h':
2332             help();
2333             return 0;
2334         case 'f':
2335             fmt = optarg;
2336             break;
2337         case 'F':
2338             out_basefmt = optarg;
2339             break;
2340         case 'b':
2341             out_baseimg = optarg;
2342             break;
2343         case 'u':
2344             unsafe = 1;
2345             break;
2346         case 'p':
2347             progress = 1;
2348             break;
2349         case 't':
2350             cache = optarg;
2351             break;
2352         case 'T':
2353             src_cache = optarg;
2354             break;
2355         case 'q':
2356             quiet = true;
2357             break;
2358         }
2359     }
2360 
2361     if (quiet) {
2362         progress = 0;
2363     }
2364 
2365     if (optind != argc - 1) {
2366         error_exit("Expecting one image file name");
2367     }
2368     if (!unsafe && !out_baseimg) {
2369         error_exit("Must specify backing file (-b) or use unsafe mode (-u)");
2370     }
2371     filename = argv[optind++];
2372 
2373     qemu_progress_init(progress, 2.0);
2374     qemu_progress_print(0, 100);
2375 
2376     flags = BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0);
2377     ret = bdrv_parse_cache_flags(cache, &flags);
2378     if (ret < 0) {
2379         error_report("Invalid cache option: %s", cache);
2380         goto out;
2381     }
2382 
2383     src_flags = BDRV_O_FLAGS;
2384     ret = bdrv_parse_cache_flags(src_cache, &src_flags);
2385     if (ret < 0) {
2386         error_report("Invalid source cache option: %s", src_cache);
2387         goto out;
2388     }
2389 
2390     /*
2391      * Open the images.
2392      *
2393      * Ignore the old backing file for unsafe rebase in case we want to correct
2394      * the reference to a renamed or moved backing file.
2395      */
2396     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
2397     if (!bs) {
2398         ret = -1;
2399         goto out;
2400     }
2401 
2402     /* Find the right drivers for the backing files */
2403     old_backing_drv = NULL;
2404     new_backing_drv = NULL;
2405 
2406     if (!unsafe && bs->backing_format[0] != '\0') {
2407         old_backing_drv = bdrv_find_format(bs->backing_format);
2408         if (old_backing_drv == NULL) {
2409             error_report("Invalid format name: '%s'", bs->backing_format);
2410             ret = -1;
2411             goto out;
2412         }
2413     }
2414 
2415     if (out_basefmt != NULL) {
2416         new_backing_drv = bdrv_find_format(out_basefmt);
2417         if (new_backing_drv == NULL) {
2418             error_report("Invalid format name: '%s'", out_basefmt);
2419             ret = -1;
2420             goto out;
2421         }
2422     }
2423 
2424     /* For safe rebasing we need to compare old and new backing file */
2425     if (!unsafe) {
2426         char backing_name[1024];
2427 
2428         bs_old_backing = bdrv_new("old_backing", &error_abort);
2429         bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2430         ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, src_flags,
2431                         old_backing_drv, &local_err);
2432         if (ret) {
2433             error_report("Could not open old backing file '%s': %s",
2434                          backing_name, error_get_pretty(local_err));
2435             error_free(local_err);
2436             goto out;
2437         }
2438         if (out_baseimg[0]) {
2439             bs_new_backing = bdrv_new("new_backing", &error_abort);
2440             ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL, src_flags,
2441                             new_backing_drv, &local_err);
2442             if (ret) {
2443                 error_report("Could not open new backing file '%s': %s",
2444                              out_baseimg, error_get_pretty(local_err));
2445                 error_free(local_err);
2446                 goto out;
2447             }
2448         }
2449     }
2450 
2451     /*
2452      * Check each unallocated cluster in the COW file. If it is unallocated,
2453      * accesses go to the backing file. We must therefore compare this cluster
2454      * in the old and new backing file, and if they differ we need to copy it
2455      * from the old backing file into the COW file.
2456      *
2457      * If qemu-img crashes during this step, no harm is done. The content of
2458      * the image is the same as the original one at any time.
2459      */
2460     if (!unsafe) {
2461         int64_t num_sectors;
2462         int64_t old_backing_num_sectors;
2463         int64_t new_backing_num_sectors = 0;
2464         uint64_t sector;
2465         int n;
2466         uint8_t * buf_old;
2467         uint8_t * buf_new;
2468         float local_progress = 0;
2469 
2470         buf_old = qemu_blockalign(bs, IO_BUF_SIZE);
2471         buf_new = qemu_blockalign(bs, IO_BUF_SIZE);
2472 
2473         num_sectors = bdrv_nb_sectors(bs);
2474         if (num_sectors < 0) {
2475             error_report("Could not get size of '%s': %s",
2476                          filename, strerror(-num_sectors));
2477             ret = -1;
2478             goto out;
2479         }
2480         old_backing_num_sectors = bdrv_nb_sectors(bs_old_backing);
2481         if (old_backing_num_sectors < 0) {
2482             char backing_name[1024];
2483 
2484             bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2485             error_report("Could not get size of '%s': %s",
2486                          backing_name, strerror(-old_backing_num_sectors));
2487             ret = -1;
2488             goto out;
2489         }
2490         if (bs_new_backing) {
2491             new_backing_num_sectors = bdrv_nb_sectors(bs_new_backing);
2492             if (new_backing_num_sectors < 0) {
2493                 error_report("Could not get size of '%s': %s",
2494                              out_baseimg, strerror(-new_backing_num_sectors));
2495                 ret = -1;
2496                 goto out;
2497             }
2498         }
2499 
2500         if (num_sectors != 0) {
2501             local_progress = (float)100 /
2502                 (num_sectors / MIN(num_sectors, IO_BUF_SIZE / 512));
2503         }
2504 
2505         for (sector = 0; sector < num_sectors; sector += n) {
2506 
2507             /* How many sectors can we handle with the next read? */
2508             if (sector + (IO_BUF_SIZE / 512) <= num_sectors) {
2509                 n = (IO_BUF_SIZE / 512);
2510             } else {
2511                 n = num_sectors - sector;
2512             }
2513 
2514             /* If the cluster is allocated, we don't need to take action */
2515             ret = bdrv_is_allocated(bs, sector, n, &n);
2516             if (ret < 0) {
2517                 error_report("error while reading image metadata: %s",
2518                              strerror(-ret));
2519                 goto out;
2520             }
2521             if (ret) {
2522                 continue;
2523             }
2524 
2525             /*
2526              * Read old and new backing file and take into consideration that
2527              * backing files may be smaller than the COW image.
2528              */
2529             if (sector >= old_backing_num_sectors) {
2530                 memset(buf_old, 0, n * BDRV_SECTOR_SIZE);
2531             } else {
2532                 if (sector + n > old_backing_num_sectors) {
2533                     n = old_backing_num_sectors - sector;
2534                 }
2535 
2536                 ret = bdrv_read(bs_old_backing, sector, buf_old, n);
2537                 if (ret < 0) {
2538                     error_report("error while reading from old backing file");
2539                     goto out;
2540                 }
2541             }
2542 
2543             if (sector >= new_backing_num_sectors || !bs_new_backing) {
2544                 memset(buf_new, 0, n * BDRV_SECTOR_SIZE);
2545             } else {
2546                 if (sector + n > new_backing_num_sectors) {
2547                     n = new_backing_num_sectors - sector;
2548                 }
2549 
2550                 ret = bdrv_read(bs_new_backing, sector, buf_new, n);
2551                 if (ret < 0) {
2552                     error_report("error while reading from new backing file");
2553                     goto out;
2554                 }
2555             }
2556 
2557             /* If they differ, we need to write to the COW file */
2558             uint64_t written = 0;
2559 
2560             while (written < n) {
2561                 int pnum;
2562 
2563                 if (compare_sectors(buf_old + written * 512,
2564                     buf_new + written * 512, n - written, &pnum))
2565                 {
2566                     ret = bdrv_write(bs, sector + written,
2567                         buf_old + written * 512, pnum);
2568                     if (ret < 0) {
2569                         error_report("Error while writing to COW image: %s",
2570                             strerror(-ret));
2571                         goto out;
2572                     }
2573                 }
2574 
2575                 written += pnum;
2576             }
2577             qemu_progress_print(local_progress, 100);
2578         }
2579 
2580         qemu_vfree(buf_old);
2581         qemu_vfree(buf_new);
2582     }
2583 
2584     /*
2585      * Change the backing file. All clusters that are different from the old
2586      * backing file are overwritten in the COW file now, so the visible content
2587      * doesn't change when we switch the backing file.
2588      */
2589     if (out_baseimg && *out_baseimg) {
2590         ret = bdrv_change_backing_file(bs, out_baseimg, out_basefmt);
2591     } else {
2592         ret = bdrv_change_backing_file(bs, NULL, NULL);
2593     }
2594 
2595     if (ret == -ENOSPC) {
2596         error_report("Could not change the backing file to '%s': No "
2597                      "space left in the file header", out_baseimg);
2598     } else if (ret < 0) {
2599         error_report("Could not change the backing file to '%s': %s",
2600             out_baseimg, strerror(-ret));
2601     }
2602 
2603     qemu_progress_print(100, 0);
2604     /*
2605      * TODO At this point it is possible to check if any clusters that are
2606      * allocated in the COW file are the same in the backing file. If so, they
2607      * could be dropped from the COW file. Don't do this before switching the
2608      * backing file, in case of a crash this would lead to corruption.
2609      */
2610 out:
2611     qemu_progress_end();
2612     /* Cleanup */
2613     if (!unsafe) {
2614         if (bs_old_backing != NULL) {
2615             bdrv_unref(bs_old_backing);
2616         }
2617         if (bs_new_backing != NULL) {
2618             bdrv_unref(bs_new_backing);
2619         }
2620     }
2621 
2622     bdrv_unref(bs);
2623     if (ret) {
2624         return 1;
2625     }
2626     return 0;
2627 }
2628 
2629 static int img_resize(int argc, char **argv)
2630 {
2631     int c, ret, relative;
2632     const char *filename, *fmt, *size;
2633     int64_t n, total_size;
2634     bool quiet = false;
2635     BlockDriverState *bs = NULL;
2636     QemuOpts *param;
2637     static QemuOptsList resize_options = {
2638         .name = "resize_options",
2639         .head = QTAILQ_HEAD_INITIALIZER(resize_options.head),
2640         .desc = {
2641             {
2642                 .name = BLOCK_OPT_SIZE,
2643                 .type = QEMU_OPT_SIZE,
2644                 .help = "Virtual disk size"
2645             }, {
2646                 /* end of list */
2647             }
2648         },
2649     };
2650 
2651     /* Remove size from argv manually so that negative numbers are not treated
2652      * as options by getopt. */
2653     if (argc < 3) {
2654         error_exit("Not enough arguments");
2655         return 1;
2656     }
2657 
2658     size = argv[--argc];
2659 
2660     /* Parse getopt arguments */
2661     fmt = NULL;
2662     for(;;) {
2663         c = getopt(argc, argv, "f:hq");
2664         if (c == -1) {
2665             break;
2666         }
2667         switch(c) {
2668         case '?':
2669         case 'h':
2670             help();
2671             break;
2672         case 'f':
2673             fmt = optarg;
2674             break;
2675         case 'q':
2676             quiet = true;
2677             break;
2678         }
2679     }
2680     if (optind != argc - 1) {
2681         error_exit("Expecting one image file name");
2682     }
2683     filename = argv[optind++];
2684 
2685     /* Choose grow, shrink, or absolute resize mode */
2686     switch (size[0]) {
2687     case '+':
2688         relative = 1;
2689         size++;
2690         break;
2691     case '-':
2692         relative = -1;
2693         size++;
2694         break;
2695     default:
2696         relative = 0;
2697         break;
2698     }
2699 
2700     /* Parse size */
2701     param = qemu_opts_create(&resize_options, NULL, 0, &error_abort);
2702     if (qemu_opt_set(param, BLOCK_OPT_SIZE, size)) {
2703         /* Error message already printed when size parsing fails */
2704         ret = -1;
2705         qemu_opts_del(param);
2706         goto out;
2707     }
2708     n = qemu_opt_get_size(param, BLOCK_OPT_SIZE, 0);
2709     qemu_opts_del(param);
2710 
2711     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR,
2712                        true, quiet);
2713     if (!bs) {
2714         ret = -1;
2715         goto out;
2716     }
2717 
2718     if (relative) {
2719         total_size = bdrv_getlength(bs) + n * relative;
2720     } else {
2721         total_size = n;
2722     }
2723     if (total_size <= 0) {
2724         error_report("New image size must be positive");
2725         ret = -1;
2726         goto out;
2727     }
2728 
2729     ret = bdrv_truncate(bs, total_size);
2730     switch (ret) {
2731     case 0:
2732         qprintf(quiet, "Image resized.\n");
2733         break;
2734     case -ENOTSUP:
2735         error_report("This image does not support resize");
2736         break;
2737     case -EACCES:
2738         error_report("Image is read-only");
2739         break;
2740     default:
2741         error_report("Error resizing image (%d)", -ret);
2742         break;
2743     }
2744 out:
2745     if (bs) {
2746         bdrv_unref(bs);
2747     }
2748     if (ret) {
2749         return 1;
2750     }
2751     return 0;
2752 }
2753 
2754 static int img_amend(int argc, char **argv)
2755 {
2756     int c, ret = 0;
2757     char *options = NULL;
2758     QemuOptsList *create_opts = NULL;
2759     QemuOpts *opts = NULL;
2760     const char *fmt = NULL, *filename, *cache;
2761     int flags;
2762     bool quiet = false;
2763     BlockDriverState *bs = NULL;
2764 
2765     cache = BDRV_DEFAULT_CACHE;
2766     for (;;) {
2767         c = getopt(argc, argv, "ho:f:t:q");
2768         if (c == -1) {
2769             break;
2770         }
2771 
2772         switch (c) {
2773             case 'h':
2774             case '?':
2775                 help();
2776                 break;
2777             case 'o':
2778                 if (!is_valid_option_list(optarg)) {
2779                     error_report("Invalid option list: %s", optarg);
2780                     ret = -1;
2781                     goto out;
2782                 }
2783                 if (!options) {
2784                     options = g_strdup(optarg);
2785                 } else {
2786                     char *old_options = options;
2787                     options = g_strdup_printf("%s,%s", options, optarg);
2788                     g_free(old_options);
2789                 }
2790                 break;
2791             case 'f':
2792                 fmt = optarg;
2793                 break;
2794             case 't':
2795                 cache = optarg;
2796                 break;
2797             case 'q':
2798                 quiet = true;
2799                 break;
2800         }
2801     }
2802 
2803     if (!options) {
2804         error_exit("Must specify options (-o)");
2805     }
2806 
2807     filename = (optind == argc - 1) ? argv[argc - 1] : NULL;
2808     if (fmt && has_help_option(options)) {
2809         /* If a format is explicitly specified (and possibly no filename is
2810          * given), print option help here */
2811         ret = print_block_option_help(filename, fmt);
2812         goto out;
2813     }
2814 
2815     if (optind != argc - 1) {
2816         error_exit("Expecting one image file name");
2817     }
2818 
2819     flags = BDRV_O_FLAGS | BDRV_O_RDWR;
2820     ret = bdrv_parse_cache_flags(cache, &flags);
2821     if (ret < 0) {
2822         error_report("Invalid cache option: %s", cache);
2823         goto out;
2824     }
2825 
2826     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
2827     if (!bs) {
2828         error_report("Could not open image '%s'", filename);
2829         ret = -1;
2830         goto out;
2831     }
2832 
2833     fmt = bs->drv->format_name;
2834 
2835     if (has_help_option(options)) {
2836         /* If the format was auto-detected, print option help here */
2837         ret = print_block_option_help(filename, fmt);
2838         goto out;
2839     }
2840 
2841     create_opts = qemu_opts_append(create_opts, bs->drv->create_opts);
2842     opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
2843     if (options && qemu_opts_do_parse(opts, options, NULL)) {
2844         error_report("Invalid options for file format '%s'", fmt);
2845         ret = -1;
2846         goto out;
2847     }
2848 
2849     ret = bdrv_amend_options(bs, opts);
2850     if (ret < 0) {
2851         error_report("Error while amending options: %s", strerror(-ret));
2852         goto out;
2853     }
2854 
2855 out:
2856     if (bs) {
2857         bdrv_unref(bs);
2858     }
2859     qemu_opts_del(opts);
2860     qemu_opts_free(create_opts);
2861     g_free(options);
2862 
2863     if (ret) {
2864         return 1;
2865     }
2866     return 0;
2867 }
2868 
2869 static const img_cmd_t img_cmds[] = {
2870 #define DEF(option, callback, arg_string)        \
2871     { option, callback },
2872 #include "qemu-img-cmds.h"
2873 #undef DEF
2874 #undef GEN_DOCS
2875     { NULL, NULL, },
2876 };
2877 
2878 int main(int argc, char **argv)
2879 {
2880     const img_cmd_t *cmd;
2881     const char *cmdname;
2882     int c;
2883     static const struct option long_options[] = {
2884         {"help", no_argument, 0, 'h'},
2885         {"version", no_argument, 0, 'v'},
2886         {0, 0, 0, 0}
2887     };
2888 
2889 #ifdef CONFIG_POSIX
2890     signal(SIGPIPE, SIG_IGN);
2891 #endif
2892 
2893     error_set_progname(argv[0]);
2894     qemu_init_exec_dir(argv[0]);
2895 
2896     qemu_init_main_loop();
2897     bdrv_init();
2898     if (argc < 2) {
2899         error_exit("Not enough arguments");
2900     }
2901     cmdname = argv[1];
2902 
2903     /* find the command */
2904     for (cmd = img_cmds; cmd->name != NULL; cmd++) {
2905         if (!strcmp(cmdname, cmd->name)) {
2906             return cmd->handler(argc - 1, argv + 1);
2907         }
2908     }
2909 
2910     c = getopt_long(argc, argv, "h", long_options, NULL);
2911 
2912     if (c == 'h') {
2913         help();
2914     }
2915     if (c == 'v') {
2916         printf(QEMU_IMG_VERSION);
2917         return 0;
2918     }
2919 
2920     /* not found */
2921     error_exit("Command not found: %s", cmdname);
2922 }
2923