xref: /openbmc/qemu/qemu-img.c (revision acb0ef58)
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 #include <glib.h>
36 
37 #define QEMU_IMG_VERSION "qemu-img version " QEMU_VERSION \
38                           ", Copyright (c) 2004-2008 Fabrice Bellard\n"
39 
40 typedef struct img_cmd_t {
41     const char *name;
42     int (*handler)(int argc, char **argv);
43 } img_cmd_t;
44 
45 enum {
46     OPTION_OUTPUT = 256,
47     OPTION_BACKING_CHAIN = 257,
48 };
49 
50 typedef enum OutputFormat {
51     OFORMAT_JSON,
52     OFORMAT_HUMAN,
53 } OutputFormat;
54 
55 /* Default to cache=writeback as data integrity is not important for qemu-tcg. */
56 #define BDRV_O_FLAGS BDRV_O_CACHE_WB
57 #define BDRV_DEFAULT_CACHE "writeback"
58 
59 static gint compare_data(gconstpointer a, gconstpointer b, gpointer user)
60 {
61     return g_strcmp0(a, b);
62 }
63 
64 static void print_format(gpointer data, gpointer user)
65 {
66     printf(" %s", (char *)data);
67 }
68 
69 static void add_format_to_seq(void *opaque, const char *fmt_name)
70 {
71     GSequence *seq = opaque;
72 
73     g_sequence_insert_sorted(seq, (gpointer)fmt_name,
74                              compare_data, NULL);
75 }
76 
77 static void QEMU_NORETURN GCC_FMT_ATTR(1, 2) error_exit(const char *fmt, ...)
78 {
79     va_list ap;
80 
81     error_printf("qemu-img: ");
82 
83     va_start(ap, fmt);
84     error_vprintf(fmt, ap);
85     va_end(ap);
86 
87     error_printf("\nTry 'qemu-img --help' for more information\n");
88     exit(EXIT_FAILURE);
89 }
90 
91 /* Please keep in synch with qemu-img.texi */
92 static void QEMU_NORETURN help(void)
93 {
94     const char *help_msg =
95            QEMU_IMG_VERSION
96            "usage: qemu-img command [command options]\n"
97            "QEMU disk image utility\n"
98            "\n"
99            "Command syntax:\n"
100 #define DEF(option, callback, arg_string)        \
101            "  " arg_string "\n"
102 #include "qemu-img-cmds.h"
103 #undef DEF
104 #undef GEN_DOCS
105            "\n"
106            "Command parameters:\n"
107            "  'filename' is a disk image filename\n"
108            "  'fmt' is the disk image format. It is guessed automatically in most cases\n"
109            "  'cache' is the cache mode used to write the output disk image, the valid\n"
110            "    options are: 'none', 'writeback' (default, except for convert), 'writethrough',\n"
111            "    'directsync' and 'unsafe' (default for convert)\n"
112            "  'size' is the disk image size in bytes. Optional suffixes\n"
113            "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M),\n"
114            "    'T' (terabyte, 1024G), 'P' (petabyte, 1024T) and 'E' (exabyte, 1024P)  are\n"
115            "    supported. 'b' is ignored.\n"
116            "  'output_filename' is the destination disk image filename\n"
117            "  'output_fmt' is the destination format\n"
118            "  'options' is a comma separated list of format specific options in a\n"
119            "    name=value format. Use -o ? for an overview of the options supported by the\n"
120            "    used format\n"
121            "  'snapshot_param' is param used for internal snapshot, format\n"
122            "    is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
123            "    '[ID_OR_NAME]'\n"
124            "  'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n"
125            "    instead\n"
126            "  '-c' indicates that target image must be compressed (qcow format only)\n"
127            "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"
128            "       match exactly. The image doesn't need a working backing file before\n"
129            "       rebasing in this case (useful for renaming the backing file)\n"
130            "  '-h' with or without a command shows this help and lists the supported formats\n"
131            "  '-p' show progress of command (only certain commands)\n"
132            "  '-q' use Quiet mode - do not print any output (except errors)\n"
133            "  '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
134            "       contain only zeros for qemu-img to create a sparse image during\n"
135            "       conversion. If the number of bytes is 0, the source will not be scanned for\n"
136            "       unallocated or zero sectors, and the destination image will always be\n"
137            "       fully allocated\n"
138            "  '--output' takes the format in which the output must be done (human or json)\n"
139            "  '-n' skips the target volume creation (useful if the volume is created\n"
140            "       prior to running qemu-img)\n"
141            "\n"
142            "Parameters to check subcommand:\n"
143            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
144            "       '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"
145            "       kinds of errors, with a higher risk of choosing the wrong fix or\n"
146            "       hiding corruption that has already occurred.\n"
147            "\n"
148            "Parameters to snapshot subcommand:\n"
149            "  'snapshot' is the name of the snapshot to create, apply or delete\n"
150            "  '-a' applies a snapshot (revert disk to saved state)\n"
151            "  '-c' creates a snapshot\n"
152            "  '-d' deletes a snapshot\n"
153            "  '-l' lists all snapshots in the given image\n"
154            "\n"
155            "Parameters to compare subcommand:\n"
156            "  '-f' first image format\n"
157            "  '-F' second image format\n"
158            "  '-s' run in Strict mode - fail on different image size or sector allocation\n";
159     GSequence *seq;
160 
161     printf("%s\nSupported formats:", help_msg);
162     seq = g_sequence_new(NULL);
163     bdrv_iterate_format(add_format_to_seq, seq);
164     g_sequence_foreach(seq, print_format, NULL);
165     printf("\n");
166     g_sequence_free(seq);
167 
168     exit(EXIT_SUCCESS);
169 }
170 
171 static int GCC_FMT_ATTR(2, 3) qprintf(bool quiet, const char *fmt, ...)
172 {
173     int ret = 0;
174     if (!quiet) {
175         va_list args;
176         va_start(args, fmt);
177         ret = vprintf(fmt, args);
178         va_end(args);
179     }
180     return ret;
181 }
182 
183 #if defined(WIN32)
184 /* XXX: put correct support for win32 */
185 static int read_password(char *buf, int buf_size)
186 {
187     int c, i;
188     printf("Password: ");
189     fflush(stdout);
190     i = 0;
191     for(;;) {
192         c = getchar();
193         if (c == '\n')
194             break;
195         if (i < (buf_size - 1))
196             buf[i++] = c;
197     }
198     buf[i] = '\0';
199     return 0;
200 }
201 
202 #else
203 
204 #include <termios.h>
205 
206 static struct termios oldtty;
207 
208 static void term_exit(void)
209 {
210     tcsetattr (0, TCSANOW, &oldtty);
211 }
212 
213 static void term_init(void)
214 {
215     struct termios tty;
216 
217     tcgetattr (0, &tty);
218     oldtty = tty;
219 
220     tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
221                           |INLCR|IGNCR|ICRNL|IXON);
222     tty.c_oflag |= OPOST;
223     tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
224     tty.c_cflag &= ~(CSIZE|PARENB);
225     tty.c_cflag |= CS8;
226     tty.c_cc[VMIN] = 1;
227     tty.c_cc[VTIME] = 0;
228 
229     tcsetattr (0, TCSANOW, &tty);
230 
231     atexit(term_exit);
232 }
233 
234 static int read_password(char *buf, int buf_size)
235 {
236     uint8_t ch;
237     int i, ret;
238 
239     printf("password: ");
240     fflush(stdout);
241     term_init();
242     i = 0;
243     for(;;) {
244         ret = read(0, &ch, 1);
245         if (ret == -1) {
246             if (errno == EAGAIN || errno == EINTR) {
247                 continue;
248             } else {
249                 ret = -1;
250                 break;
251             }
252         } else if (ret == 0) {
253             ret = -1;
254             break;
255         } else {
256             if (ch == '\r') {
257                 ret = 0;
258                 break;
259             }
260             if (i < (buf_size - 1))
261                 buf[i++] = ch;
262         }
263     }
264     term_exit();
265     buf[i] = '\0';
266     printf("\n");
267     return ret;
268 }
269 #endif
270 
271 static int print_block_option_help(const char *filename, const char *fmt)
272 {
273     BlockDriver *drv, *proto_drv;
274     QEMUOptionParameter *create_options = NULL;
275 
276     /* Find driver and parse its options */
277     drv = bdrv_find_format(fmt);
278     if (!drv) {
279         error_report("Unknown file format '%s'", fmt);
280         return 1;
281     }
282 
283     create_options = append_option_parameters(create_options,
284                                               drv->create_options);
285 
286     if (filename) {
287         proto_drv = bdrv_find_protocol(filename, true);
288         if (!proto_drv) {
289             error_report("Unknown protocol '%s'", filename);
290             free_option_parameters(create_options);
291             return 1;
292         }
293         create_options = append_option_parameters(create_options,
294                                                   proto_drv->create_options);
295     }
296 
297     print_option_help(create_options);
298     free_option_parameters(create_options);
299     return 0;
300 }
301 
302 static BlockDriverState *bdrv_new_open(const char *id,
303                                        const char *filename,
304                                        const char *fmt,
305                                        int flags,
306                                        bool require_io,
307                                        bool quiet)
308 {
309     BlockDriverState *bs;
310     BlockDriver *drv;
311     char password[256];
312     Error *local_err = NULL;
313     int ret;
314 
315     bs = bdrv_new(id, &error_abort);
316 
317     if (fmt) {
318         drv = bdrv_find_format(fmt);
319         if (!drv) {
320             error_report("Unknown file format '%s'", fmt);
321             goto fail;
322         }
323     } else {
324         drv = NULL;
325     }
326 
327     ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err);
328     if (ret < 0) {
329         error_report("Could not open '%s': %s", filename,
330                      error_get_pretty(local_err));
331         error_free(local_err);
332         goto fail;
333     }
334 
335     if (bdrv_is_encrypted(bs) && require_io) {
336         qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);
337         if (read_password(password, sizeof(password)) < 0) {
338             error_report("No password given");
339             goto fail;
340         }
341         if (bdrv_set_key(bs, password) < 0) {
342             error_report("invalid password");
343             goto fail;
344         }
345     }
346     return bs;
347 fail:
348     bdrv_unref(bs);
349     return NULL;
350 }
351 
352 static int add_old_style_options(const char *fmt, QEMUOptionParameter *list,
353                                  const char *base_filename,
354                                  const char *base_fmt)
355 {
356     if (base_filename) {
357         if (set_option_parameter(list, BLOCK_OPT_BACKING_FILE, base_filename)) {
358             error_report("Backing file not supported for file format '%s'",
359                          fmt);
360             return -1;
361         }
362     }
363     if (base_fmt) {
364         if (set_option_parameter(list, BLOCK_OPT_BACKING_FMT, base_fmt)) {
365             error_report("Backing file format not supported for file "
366                          "format '%s'", fmt);
367             return -1;
368         }
369     }
370     return 0;
371 }
372 
373 static int img_create(int argc, char **argv)
374 {
375     int c;
376     uint64_t img_size = -1;
377     const char *fmt = "raw";
378     const char *base_fmt = NULL;
379     const char *filename;
380     const char *base_filename = NULL;
381     char *options = NULL;
382     Error *local_err = NULL;
383     bool quiet = false;
384 
385     for(;;) {
386         c = getopt(argc, argv, "F:b:f:he6o:q");
387         if (c == -1) {
388             break;
389         }
390         switch(c) {
391         case '?':
392         case 'h':
393             help();
394             break;
395         case 'F':
396             base_fmt = optarg;
397             break;
398         case 'b':
399             base_filename = optarg;
400             break;
401         case 'f':
402             fmt = optarg;
403             break;
404         case 'e':
405             error_report("option -e is deprecated, please use \'-o "
406                   "encryption\' instead!");
407             goto fail;
408         case '6':
409             error_report("option -6 is deprecated, please use \'-o "
410                   "compat6\' instead!");
411             goto fail;
412         case 'o':
413             if (!is_valid_option_list(optarg)) {
414                 error_report("Invalid option list: %s", optarg);
415                 goto fail;
416             }
417             if (!options) {
418                 options = g_strdup(optarg);
419             } else {
420                 char *old_options = options;
421                 options = g_strdup_printf("%s,%s", options, optarg);
422                 g_free(old_options);
423             }
424             break;
425         case 'q':
426             quiet = true;
427             break;
428         }
429     }
430 
431     /* Get the filename */
432     filename = (optind < argc) ? argv[optind] : NULL;
433     if (options && has_help_option(options)) {
434         g_free(options);
435         return print_block_option_help(filename, fmt);
436     }
437 
438     if (optind >= argc) {
439         error_exit("Expecting image file name");
440     }
441     optind++;
442 
443     /* Get image size, if specified */
444     if (optind < argc) {
445         int64_t sval;
446         char *end;
447         sval = strtosz_suffix(argv[optind++], &end, STRTOSZ_DEFSUFFIX_B);
448         if (sval < 0 || *end) {
449             if (sval == -ERANGE) {
450                 error_report("Image size must be less than 8 EiB!");
451             } else {
452                 error_report("Invalid image size specified! You may use k, M, "
453                       "G, T, P or E suffixes for ");
454                 error_report("kilobytes, megabytes, gigabytes, terabytes, "
455                              "petabytes and exabytes.");
456             }
457             goto fail;
458         }
459         img_size = (uint64_t)sval;
460     }
461     if (optind != argc) {
462         error_exit("Unexpected argument: %s", argv[optind]);
463     }
464 
465     bdrv_img_create(filename, fmt, base_filename, base_fmt,
466                     options, img_size, BDRV_O_FLAGS, &local_err, quiet);
467     if (local_err) {
468         error_report("%s: %s", filename, error_get_pretty(local_err));
469         error_free(local_err);
470         goto fail;
471     }
472 
473     g_free(options);
474     return 0;
475 
476 fail:
477     g_free(options);
478     return 1;
479 }
480 
481 static void dump_json_image_check(ImageCheck *check, bool quiet)
482 {
483     Error *local_err = NULL;
484     QString *str;
485     QmpOutputVisitor *ov = qmp_output_visitor_new();
486     QObject *obj;
487     visit_type_ImageCheck(qmp_output_get_visitor(ov),
488                           &check, NULL, &local_err);
489     obj = qmp_output_get_qobject(ov);
490     str = qobject_to_json_pretty(obj);
491     assert(str != NULL);
492     qprintf(quiet, "%s\n", qstring_get_str(str));
493     qobject_decref(obj);
494     qmp_output_visitor_cleanup(ov);
495     QDECREF(str);
496 }
497 
498 static void dump_human_image_check(ImageCheck *check, bool quiet)
499 {
500     if (!(check->corruptions || check->leaks || check->check_errors)) {
501         qprintf(quiet, "No errors were found on the image.\n");
502     } else {
503         if (check->corruptions) {
504             qprintf(quiet, "\n%" PRId64 " errors were found on the image.\n"
505                     "Data may be corrupted, or further writes to the image "
506                     "may corrupt it.\n",
507                     check->corruptions);
508         }
509 
510         if (check->leaks) {
511             qprintf(quiet,
512                     "\n%" PRId64 " leaked clusters were found on the image.\n"
513                     "This means waste of disk space, but no harm to data.\n",
514                     check->leaks);
515         }
516 
517         if (check->check_errors) {
518             qprintf(quiet,
519                     "\n%" PRId64
520                     " internal errors have occurred during the check.\n",
521                     check->check_errors);
522         }
523     }
524 
525     if (check->total_clusters != 0 && check->allocated_clusters != 0) {
526         qprintf(quiet, "%" PRId64 "/%" PRId64 " = %0.2f%% allocated, "
527                 "%0.2f%% fragmented, %0.2f%% compressed clusters\n",
528                 check->allocated_clusters, check->total_clusters,
529                 check->allocated_clusters * 100.0 / check->total_clusters,
530                 check->fragmented_clusters * 100.0 / check->allocated_clusters,
531                 check->compressed_clusters * 100.0 /
532                 check->allocated_clusters);
533     }
534 
535     if (check->image_end_offset) {
536         qprintf(quiet,
537                 "Image end offset: %" PRId64 "\n", check->image_end_offset);
538     }
539 }
540 
541 static int collect_image_check(BlockDriverState *bs,
542                    ImageCheck *check,
543                    const char *filename,
544                    const char *fmt,
545                    int fix)
546 {
547     int ret;
548     BdrvCheckResult result;
549 
550     ret = bdrv_check(bs, &result, fix);
551     if (ret < 0) {
552         return ret;
553     }
554 
555     check->filename                 = g_strdup(filename);
556     check->format                   = g_strdup(bdrv_get_format_name(bs));
557     check->check_errors             = result.check_errors;
558     check->corruptions              = result.corruptions;
559     check->has_corruptions          = result.corruptions != 0;
560     check->leaks                    = result.leaks;
561     check->has_leaks                = result.leaks != 0;
562     check->corruptions_fixed        = result.corruptions_fixed;
563     check->has_corruptions_fixed    = result.corruptions != 0;
564     check->leaks_fixed              = result.leaks_fixed;
565     check->has_leaks_fixed          = result.leaks != 0;
566     check->image_end_offset         = result.image_end_offset;
567     check->has_image_end_offset     = result.image_end_offset != 0;
568     check->total_clusters           = result.bfi.total_clusters;
569     check->has_total_clusters       = result.bfi.total_clusters != 0;
570     check->allocated_clusters       = result.bfi.allocated_clusters;
571     check->has_allocated_clusters   = result.bfi.allocated_clusters != 0;
572     check->fragmented_clusters      = result.bfi.fragmented_clusters;
573     check->has_fragmented_clusters  = result.bfi.fragmented_clusters != 0;
574     check->compressed_clusters      = result.bfi.compressed_clusters;
575     check->has_compressed_clusters  = result.bfi.compressed_clusters != 0;
576 
577     return 0;
578 }
579 
580 /*
581  * Checks an image for consistency. Exit codes:
582  *
583  *  0 - Check completed, image is good
584  *  1 - Check not completed because of internal errors
585  *  2 - Check completed, image is corrupted
586  *  3 - Check completed, image has leaked clusters, but is good otherwise
587  * 63 - Checks are not supported by the image format
588  */
589 static int img_check(int argc, char **argv)
590 {
591     int c, ret;
592     OutputFormat output_format = OFORMAT_HUMAN;
593     const char *filename, *fmt, *output;
594     BlockDriverState *bs;
595     int fix = 0;
596     int flags = BDRV_O_FLAGS | BDRV_O_CHECK;
597     ImageCheck *check;
598     bool quiet = false;
599 
600     fmt = NULL;
601     output = NULL;
602     for(;;) {
603         int option_index = 0;
604         static const struct option long_options[] = {
605             {"help", no_argument, 0, 'h'},
606             {"format", required_argument, 0, 'f'},
607             {"repair", required_argument, 0, 'r'},
608             {"output", required_argument, 0, OPTION_OUTPUT},
609             {0, 0, 0, 0}
610         };
611         c = getopt_long(argc, argv, "f:hr:q",
612                         long_options, &option_index);
613         if (c == -1) {
614             break;
615         }
616         switch(c) {
617         case '?':
618         case 'h':
619             help();
620             break;
621         case 'f':
622             fmt = optarg;
623             break;
624         case 'r':
625             flags |= BDRV_O_RDWR;
626 
627             if (!strcmp(optarg, "leaks")) {
628                 fix = BDRV_FIX_LEAKS;
629             } else if (!strcmp(optarg, "all")) {
630                 fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS;
631             } else {
632                 error_exit("Unknown option value for -r "
633                            "(expecting 'leaks' or 'all'): %s", optarg);
634             }
635             break;
636         case OPTION_OUTPUT:
637             output = optarg;
638             break;
639         case 'q':
640             quiet = true;
641             break;
642         }
643     }
644     if (optind != argc - 1) {
645         error_exit("Expecting one image file name");
646     }
647     filename = argv[optind++];
648 
649     if (output && !strcmp(output, "json")) {
650         output_format = OFORMAT_JSON;
651     } else if (output && !strcmp(output, "human")) {
652         output_format = OFORMAT_HUMAN;
653     } else if (output) {
654         error_report("--output must be used with human or json as argument.");
655         return 1;
656     }
657 
658     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
659     if (!bs) {
660         return 1;
661     }
662 
663     check = g_new0(ImageCheck, 1);
664     ret = collect_image_check(bs, check, filename, fmt, fix);
665 
666     if (ret == -ENOTSUP) {
667         error_report("This image format does not support checks");
668         ret = 63;
669         goto fail;
670     }
671 
672     if (check->corruptions_fixed || check->leaks_fixed) {
673         int corruptions_fixed, leaks_fixed;
674 
675         leaks_fixed         = check->leaks_fixed;
676         corruptions_fixed   = check->corruptions_fixed;
677 
678         if (output_format == OFORMAT_HUMAN) {
679             qprintf(quiet,
680                     "The following inconsistencies were found and repaired:\n\n"
681                     "    %" PRId64 " leaked clusters\n"
682                     "    %" PRId64 " corruptions\n\n"
683                     "Double checking the fixed image now...\n",
684                     check->leaks_fixed,
685                     check->corruptions_fixed);
686         }
687 
688         ret = collect_image_check(bs, check, filename, fmt, 0);
689 
690         check->leaks_fixed          = leaks_fixed;
691         check->corruptions_fixed    = corruptions_fixed;
692     }
693 
694     switch (output_format) {
695     case OFORMAT_HUMAN:
696         dump_human_image_check(check, quiet);
697         break;
698     case OFORMAT_JSON:
699         dump_json_image_check(check, quiet);
700         break;
701     }
702 
703     if (ret || check->check_errors) {
704         ret = 1;
705         goto fail;
706     }
707 
708     if (check->corruptions) {
709         ret = 2;
710     } else if (check->leaks) {
711         ret = 3;
712     } else {
713         ret = 0;
714     }
715 
716 fail:
717     qapi_free_ImageCheck(check);
718     bdrv_unref(bs);
719 
720     return ret;
721 }
722 
723 static int img_commit(int argc, char **argv)
724 {
725     int c, ret, flags;
726     const char *filename, *fmt, *cache;
727     BlockDriverState *bs;
728     bool quiet = false;
729 
730     fmt = NULL;
731     cache = BDRV_DEFAULT_CACHE;
732     for(;;) {
733         c = getopt(argc, argv, "f:ht:q");
734         if (c == -1) {
735             break;
736         }
737         switch(c) {
738         case '?':
739         case 'h':
740             help();
741             break;
742         case 'f':
743             fmt = optarg;
744             break;
745         case 't':
746             cache = optarg;
747             break;
748         case 'q':
749             quiet = true;
750             break;
751         }
752     }
753     if (optind != argc - 1) {
754         error_exit("Expecting one image file name");
755     }
756     filename = argv[optind++];
757 
758     flags = BDRV_O_RDWR;
759     ret = bdrv_parse_cache_flags(cache, &flags);
760     if (ret < 0) {
761         error_report("Invalid cache option: %s", cache);
762         return -1;
763     }
764 
765     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
766     if (!bs) {
767         return 1;
768     }
769     ret = bdrv_commit(bs);
770     switch(ret) {
771     case 0:
772         qprintf(quiet, "Image committed.\n");
773         break;
774     case -ENOENT:
775         error_report("No disk inserted");
776         break;
777     case -EACCES:
778         error_report("Image is read-only");
779         break;
780     case -ENOTSUP:
781         error_report("Image is already committed");
782         break;
783     default:
784         error_report("Error while committing image");
785         break;
786     }
787 
788     bdrv_unref(bs);
789     if (ret) {
790         return 1;
791     }
792     return 0;
793 }
794 
795 /*
796  * Returns true iff the first sector pointed to by 'buf' contains at least
797  * a non-NUL byte.
798  *
799  * 'pnum' is set to the number of sectors (including and immediately following
800  * the first one) that are known to be in the same allocated/unallocated state.
801  */
802 static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)
803 {
804     bool is_zero;
805     int i;
806 
807     if (n <= 0) {
808         *pnum = 0;
809         return 0;
810     }
811     is_zero = buffer_is_zero(buf, 512);
812     for(i = 1; i < n; i++) {
813         buf += 512;
814         if (is_zero != buffer_is_zero(buf, 512)) {
815             break;
816         }
817     }
818     *pnum = i;
819     return !is_zero;
820 }
821 
822 /*
823  * Like is_allocated_sectors, but if the buffer starts with a used sector,
824  * up to 'min' consecutive sectors containing zeros are ignored. This avoids
825  * breaking up write requests for only small sparse areas.
826  */
827 static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,
828     int min)
829 {
830     int ret;
831     int num_checked, num_used;
832 
833     if (n < min) {
834         min = n;
835     }
836 
837     ret = is_allocated_sectors(buf, n, pnum);
838     if (!ret) {
839         return ret;
840     }
841 
842     num_used = *pnum;
843     buf += BDRV_SECTOR_SIZE * *pnum;
844     n -= *pnum;
845     num_checked = num_used;
846 
847     while (n > 0) {
848         ret = is_allocated_sectors(buf, n, pnum);
849 
850         buf += BDRV_SECTOR_SIZE * *pnum;
851         n -= *pnum;
852         num_checked += *pnum;
853         if (ret) {
854             num_used = num_checked;
855         } else if (*pnum >= min) {
856             break;
857         }
858     }
859 
860     *pnum = num_used;
861     return 1;
862 }
863 
864 /*
865  * Compares two buffers sector by sector. Returns 0 if the first sector of both
866  * buffers matches, non-zero otherwise.
867  *
868  * pnum is set to the number of sectors (including and immediately following
869  * the first one) that are known to have the same comparison result
870  */
871 static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
872     int *pnum)
873 {
874     int res, i;
875 
876     if (n <= 0) {
877         *pnum = 0;
878         return 0;
879     }
880 
881     res = !!memcmp(buf1, buf2, 512);
882     for(i = 1; i < n; i++) {
883         buf1 += 512;
884         buf2 += 512;
885 
886         if (!!memcmp(buf1, buf2, 512) != res) {
887             break;
888         }
889     }
890 
891     *pnum = i;
892     return res;
893 }
894 
895 #define IO_BUF_SIZE (2 * 1024 * 1024)
896 
897 static int64_t sectors_to_bytes(int64_t sectors)
898 {
899     return sectors << BDRV_SECTOR_BITS;
900 }
901 
902 static int64_t sectors_to_process(int64_t total, int64_t from)
903 {
904     return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);
905 }
906 
907 /*
908  * Check if passed sectors are empty (not allocated or contain only 0 bytes)
909  *
910  * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero
911  * data and negative value on error.
912  *
913  * @param bs:  Driver used for accessing file
914  * @param sect_num: Number of first sector to check
915  * @param sect_count: Number of sectors to check
916  * @param filename: Name of disk file we are checking (logging purpose)
917  * @param buffer: Allocated buffer for storing read data
918  * @param quiet: Flag for quiet mode
919  */
920 static int check_empty_sectors(BlockDriverState *bs, int64_t sect_num,
921                                int sect_count, const char *filename,
922                                uint8_t *buffer, bool quiet)
923 {
924     int pnum, ret = 0;
925     ret = bdrv_read(bs, sect_num, buffer, sect_count);
926     if (ret < 0) {
927         error_report("Error while reading offset %" PRId64 " of %s: %s",
928                      sectors_to_bytes(sect_num), filename, strerror(-ret));
929         return ret;
930     }
931     ret = is_allocated_sectors(buffer, sect_count, &pnum);
932     if (ret || pnum != sect_count) {
933         qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
934                 sectors_to_bytes(ret ? sect_num : sect_num + pnum));
935         return 1;
936     }
937 
938     return 0;
939 }
940 
941 /*
942  * Compares two images. Exit codes:
943  *
944  * 0 - Images are identical
945  * 1 - Images differ
946  * >1 - Error occurred
947  */
948 static int img_compare(int argc, char **argv)
949 {
950     const char *fmt1 = NULL, *fmt2 = NULL, *filename1, *filename2;
951     BlockDriverState *bs1, *bs2;
952     int64_t total_sectors1, total_sectors2;
953     uint8_t *buf1 = NULL, *buf2 = NULL;
954     int pnum1, pnum2;
955     int allocated1, allocated2;
956     int ret = 0; /* return value - 0 Ident, 1 Different, >1 Error */
957     bool progress = false, quiet = false, strict = false;
958     int64_t total_sectors;
959     int64_t sector_num = 0;
960     int64_t nb_sectors;
961     int c, pnum;
962     uint64_t bs_sectors;
963     uint64_t progress_base;
964 
965     for (;;) {
966         c = getopt(argc, argv, "hpf:F:sq");
967         if (c == -1) {
968             break;
969         }
970         switch (c) {
971         case '?':
972         case 'h':
973             help();
974             break;
975         case 'f':
976             fmt1 = optarg;
977             break;
978         case 'F':
979             fmt2 = optarg;
980             break;
981         case 'p':
982             progress = true;
983             break;
984         case 'q':
985             quiet = true;
986             break;
987         case 's':
988             strict = true;
989             break;
990         }
991     }
992 
993     /* Progress is not shown in Quiet mode */
994     if (quiet) {
995         progress = false;
996     }
997 
998 
999     if (optind != argc - 2) {
1000         error_exit("Expecting two image file names");
1001     }
1002     filename1 = argv[optind++];
1003     filename2 = argv[optind++];
1004 
1005     /* Initialize before goto out */
1006     qemu_progress_init(progress, 2.0);
1007 
1008     bs1 = bdrv_new_open("image 1", filename1, fmt1, BDRV_O_FLAGS, true, quiet);
1009     if (!bs1) {
1010         error_report("Can't open file %s", filename1);
1011         ret = 2;
1012         goto out3;
1013     }
1014 
1015     bs2 = bdrv_new_open("image 2", filename2, fmt2, BDRV_O_FLAGS, true, quiet);
1016     if (!bs2) {
1017         error_report("Can't open file %s", filename2);
1018         ret = 2;
1019         goto out2;
1020     }
1021 
1022     buf1 = qemu_blockalign(bs1, IO_BUF_SIZE);
1023     buf2 = qemu_blockalign(bs2, IO_BUF_SIZE);
1024     bdrv_get_geometry(bs1, &bs_sectors);
1025     total_sectors1 = bs_sectors;
1026     bdrv_get_geometry(bs2, &bs_sectors);
1027     total_sectors2 = bs_sectors;
1028     total_sectors = MIN(total_sectors1, total_sectors2);
1029     progress_base = MAX(total_sectors1, total_sectors2);
1030 
1031     qemu_progress_print(0, 100);
1032 
1033     if (strict && total_sectors1 != total_sectors2) {
1034         ret = 1;
1035         qprintf(quiet, "Strict mode: Image size mismatch!\n");
1036         goto out;
1037     }
1038 
1039     for (;;) {
1040         nb_sectors = sectors_to_process(total_sectors, sector_num);
1041         if (nb_sectors <= 0) {
1042             break;
1043         }
1044         allocated1 = bdrv_is_allocated_above(bs1, NULL, sector_num, nb_sectors,
1045                                              &pnum1);
1046         if (allocated1 < 0) {
1047             ret = 3;
1048             error_report("Sector allocation test failed for %s", filename1);
1049             goto out;
1050         }
1051 
1052         allocated2 = bdrv_is_allocated_above(bs2, NULL, sector_num, nb_sectors,
1053                                              &pnum2);
1054         if (allocated2 < 0) {
1055             ret = 3;
1056             error_report("Sector allocation test failed for %s", filename2);
1057             goto out;
1058         }
1059         nb_sectors = MIN(pnum1, pnum2);
1060 
1061         if (allocated1 == allocated2) {
1062             if (allocated1) {
1063                 ret = bdrv_read(bs1, sector_num, buf1, nb_sectors);
1064                 if (ret < 0) {
1065                     error_report("Error while reading offset %" PRId64 " of %s:"
1066                                  " %s", sectors_to_bytes(sector_num), filename1,
1067                                  strerror(-ret));
1068                     ret = 4;
1069                     goto out;
1070                 }
1071                 ret = bdrv_read(bs2, sector_num, buf2, nb_sectors);
1072                 if (ret < 0) {
1073                     error_report("Error while reading offset %" PRId64
1074                                  " of %s: %s", sectors_to_bytes(sector_num),
1075                                  filename2, strerror(-ret));
1076                     ret = 4;
1077                     goto out;
1078                 }
1079                 ret = compare_sectors(buf1, buf2, nb_sectors, &pnum);
1080                 if (ret || pnum != nb_sectors) {
1081                     qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
1082                             sectors_to_bytes(
1083                                 ret ? sector_num : sector_num + pnum));
1084                     ret = 1;
1085                     goto out;
1086                 }
1087             }
1088         } else {
1089             if (strict) {
1090                 ret = 1;
1091                 qprintf(quiet, "Strict mode: Offset %" PRId64
1092                         " allocation mismatch!\n",
1093                         sectors_to_bytes(sector_num));
1094                 goto out;
1095             }
1096 
1097             if (allocated1) {
1098                 ret = check_empty_sectors(bs1, sector_num, nb_sectors,
1099                                           filename1, buf1, quiet);
1100             } else {
1101                 ret = check_empty_sectors(bs2, sector_num, nb_sectors,
1102                                           filename2, buf1, quiet);
1103             }
1104             if (ret) {
1105                 if (ret < 0) {
1106                     error_report("Error while reading offset %" PRId64 ": %s",
1107                                  sectors_to_bytes(sector_num), strerror(-ret));
1108                     ret = 4;
1109                 }
1110                 goto out;
1111             }
1112         }
1113         sector_num += nb_sectors;
1114         qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1115     }
1116 
1117     if (total_sectors1 != total_sectors2) {
1118         BlockDriverState *bs_over;
1119         int64_t total_sectors_over;
1120         const char *filename_over;
1121 
1122         qprintf(quiet, "Warning: Image size mismatch!\n");
1123         if (total_sectors1 > total_sectors2) {
1124             total_sectors_over = total_sectors1;
1125             bs_over = bs1;
1126             filename_over = filename1;
1127         } else {
1128             total_sectors_over = total_sectors2;
1129             bs_over = bs2;
1130             filename_over = filename2;
1131         }
1132 
1133         for (;;) {
1134             nb_sectors = sectors_to_process(total_sectors_over, sector_num);
1135             if (nb_sectors <= 0) {
1136                 break;
1137             }
1138             ret = bdrv_is_allocated_above(bs_over, NULL, sector_num,
1139                                           nb_sectors, &pnum);
1140             if (ret < 0) {
1141                 ret = 3;
1142                 error_report("Sector allocation test failed for %s",
1143                              filename_over);
1144                 goto out;
1145 
1146             }
1147             nb_sectors = pnum;
1148             if (ret) {
1149                 ret = check_empty_sectors(bs_over, sector_num, nb_sectors,
1150                                           filename_over, buf1, quiet);
1151                 if (ret) {
1152                     if (ret < 0) {
1153                         error_report("Error while reading offset %" PRId64
1154                                      " of %s: %s", sectors_to_bytes(sector_num),
1155                                      filename_over, strerror(-ret));
1156                         ret = 4;
1157                     }
1158                     goto out;
1159                 }
1160             }
1161             sector_num += nb_sectors;
1162             qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1163         }
1164     }
1165 
1166     qprintf(quiet, "Images are identical.\n");
1167     ret = 0;
1168 
1169 out:
1170     bdrv_unref(bs2);
1171     qemu_vfree(buf1);
1172     qemu_vfree(buf2);
1173 out2:
1174     bdrv_unref(bs1);
1175 out3:
1176     qemu_progress_end();
1177     return ret;
1178 }
1179 
1180 static int img_convert(int argc, char **argv)
1181 {
1182     int c, n, n1, bs_n, bs_i, compress, cluster_sectors, skip_create;
1183     int64_t ret = 0;
1184     int progress = 0, flags;
1185     const char *fmt, *out_fmt, *cache, *out_baseimg, *out_filename;
1186     BlockDriver *drv, *proto_drv;
1187     BlockDriverState **bs = NULL, *out_bs = NULL;
1188     int64_t total_sectors, nb_sectors, sector_num, bs_offset;
1189     uint64_t bs_sectors;
1190     uint8_t * buf = NULL;
1191     size_t bufsectors = IO_BUF_SIZE / BDRV_SECTOR_SIZE;
1192     const uint8_t *buf1;
1193     BlockDriverInfo bdi;
1194     QEMUOptionParameter *param = NULL, *create_options = NULL;
1195     QEMUOptionParameter *out_baseimg_param;
1196     char *options = NULL;
1197     const char *snapshot_name = NULL;
1198     int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */
1199     bool quiet = false;
1200     Error *local_err = NULL;
1201     QemuOpts *sn_opts = NULL;
1202 
1203     fmt = NULL;
1204     out_fmt = "raw";
1205     cache = "unsafe";
1206     out_baseimg = NULL;
1207     compress = 0;
1208     skip_create = 0;
1209     for(;;) {
1210         c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:qnl:");
1211         if (c == -1) {
1212             break;
1213         }
1214         switch(c) {
1215         case '?':
1216         case 'h':
1217             help();
1218             break;
1219         case 'f':
1220             fmt = optarg;
1221             break;
1222         case 'O':
1223             out_fmt = optarg;
1224             break;
1225         case 'B':
1226             out_baseimg = optarg;
1227             break;
1228         case 'c':
1229             compress = 1;
1230             break;
1231         case 'e':
1232             error_report("option -e is deprecated, please use \'-o "
1233                   "encryption\' instead!");
1234             ret = -1;
1235             goto fail_getopt;
1236         case '6':
1237             error_report("option -6 is deprecated, please use \'-o "
1238                   "compat6\' instead!");
1239             ret = -1;
1240             goto fail_getopt;
1241         case 'o':
1242             if (!is_valid_option_list(optarg)) {
1243                 error_report("Invalid option list: %s", optarg);
1244                 ret = -1;
1245                 goto fail_getopt;
1246             }
1247             if (!options) {
1248                 options = g_strdup(optarg);
1249             } else {
1250                 char *old_options = options;
1251                 options = g_strdup_printf("%s,%s", options, optarg);
1252                 g_free(old_options);
1253             }
1254             break;
1255         case 's':
1256             snapshot_name = optarg;
1257             break;
1258         case 'l':
1259             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
1260                 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0);
1261                 if (!sn_opts) {
1262                     error_report("Failed in parsing snapshot param '%s'",
1263                                  optarg);
1264                     ret = -1;
1265                     goto fail_getopt;
1266                 }
1267             } else {
1268                 snapshot_name = optarg;
1269             }
1270             break;
1271         case 'S':
1272         {
1273             int64_t sval;
1274             char *end;
1275             sval = strtosz_suffix(optarg, &end, STRTOSZ_DEFSUFFIX_B);
1276             if (sval < 0 || *end) {
1277                 error_report("Invalid minimum zero buffer size for sparse output specified");
1278                 ret = -1;
1279                 goto fail_getopt;
1280             }
1281 
1282             min_sparse = sval / BDRV_SECTOR_SIZE;
1283             break;
1284         }
1285         case 'p':
1286             progress = 1;
1287             break;
1288         case 't':
1289             cache = optarg;
1290             break;
1291         case 'q':
1292             quiet = true;
1293             break;
1294         case 'n':
1295             skip_create = 1;
1296             break;
1297         }
1298     }
1299 
1300     /* Initialize before goto out */
1301     if (quiet) {
1302         progress = 0;
1303     }
1304     qemu_progress_init(progress, 1.0);
1305 
1306 
1307     bs_n = argc - optind - 1;
1308     out_filename = bs_n >= 1 ? argv[argc - 1] : NULL;
1309 
1310     if (options && has_help_option(options)) {
1311         ret = print_block_option_help(out_filename, out_fmt);
1312         goto out;
1313     }
1314 
1315     if (bs_n < 1) {
1316         error_exit("Must specify image file name");
1317     }
1318 
1319 
1320     if (bs_n > 1 && out_baseimg) {
1321         error_report("-B makes no sense when concatenating multiple input "
1322                      "images");
1323         ret = -1;
1324         goto out;
1325     }
1326 
1327     qemu_progress_print(0, 100);
1328 
1329     bs = g_malloc0(bs_n * sizeof(BlockDriverState *));
1330 
1331     total_sectors = 0;
1332     for (bs_i = 0; bs_i < bs_n; bs_i++) {
1333         char *id = bs_n > 1 ? g_strdup_printf("source %d", bs_i)
1334                             : g_strdup("source");
1335         bs[bs_i] = bdrv_new_open(id, argv[optind + bs_i], fmt, BDRV_O_FLAGS,
1336                                  true, quiet);
1337         g_free(id);
1338         if (!bs[bs_i]) {
1339             error_report("Could not open '%s'", argv[optind + bs_i]);
1340             ret = -1;
1341             goto out;
1342         }
1343         bdrv_get_geometry(bs[bs_i], &bs_sectors);
1344         total_sectors += bs_sectors;
1345     }
1346 
1347     if (sn_opts) {
1348         ret = bdrv_snapshot_load_tmp(bs[0],
1349                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1350                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1351                                      &local_err);
1352     } else if (snapshot_name != NULL) {
1353         if (bs_n > 1) {
1354             error_report("No support for concatenating multiple snapshot");
1355             ret = -1;
1356             goto out;
1357         }
1358 
1359         bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err);
1360     }
1361     if (local_err) {
1362         error_report("Failed to load snapshot: %s",
1363                      error_get_pretty(local_err));
1364         error_free(local_err);
1365         ret = -1;
1366         goto out;
1367     }
1368 
1369     /* Find driver and parse its options */
1370     drv = bdrv_find_format(out_fmt);
1371     if (!drv) {
1372         error_report("Unknown file format '%s'", out_fmt);
1373         ret = -1;
1374         goto out;
1375     }
1376 
1377     proto_drv = bdrv_find_protocol(out_filename, true);
1378     if (!proto_drv) {
1379         error_report("Unknown protocol '%s'", out_filename);
1380         ret = -1;
1381         goto out;
1382     }
1383 
1384     create_options = append_option_parameters(create_options,
1385                                               drv->create_options);
1386     create_options = append_option_parameters(create_options,
1387                                               proto_drv->create_options);
1388 
1389     if (options) {
1390         param = parse_option_parameters(options, create_options, param);
1391         if (param == NULL) {
1392             error_report("Invalid options for file format '%s'.", out_fmt);
1393             ret = -1;
1394             goto out;
1395         }
1396     } else {
1397         param = parse_option_parameters("", create_options, param);
1398     }
1399 
1400     set_option_parameter_int(param, BLOCK_OPT_SIZE, total_sectors * 512);
1401     ret = add_old_style_options(out_fmt, param, out_baseimg, NULL);
1402     if (ret < 0) {
1403         goto out;
1404     }
1405 
1406     /* Get backing file name if -o backing_file was used */
1407     out_baseimg_param = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
1408     if (out_baseimg_param) {
1409         out_baseimg = out_baseimg_param->value.s;
1410     }
1411 
1412     /* Check if compression is supported */
1413     if (compress) {
1414         QEMUOptionParameter *encryption =
1415             get_option_parameter(param, BLOCK_OPT_ENCRYPT);
1416         QEMUOptionParameter *preallocation =
1417             get_option_parameter(param, BLOCK_OPT_PREALLOC);
1418 
1419         if (!drv->bdrv_write_compressed) {
1420             error_report("Compression not supported for this file format");
1421             ret = -1;
1422             goto out;
1423         }
1424 
1425         if (encryption && encryption->value.n) {
1426             error_report("Compression and encryption not supported at "
1427                          "the same time");
1428             ret = -1;
1429             goto out;
1430         }
1431 
1432         if (preallocation && preallocation->value.s
1433             && strcmp(preallocation->value.s, "off"))
1434         {
1435             error_report("Compression and preallocation not supported at "
1436                          "the same time");
1437             ret = -1;
1438             goto out;
1439         }
1440     }
1441 
1442     if (!skip_create) {
1443         /* Create the new image */
1444         ret = bdrv_create(drv, out_filename, param, &local_err);
1445         if (ret < 0) {
1446             error_report("%s: error while converting %s: %s",
1447                          out_filename, out_fmt, error_get_pretty(local_err));
1448             error_free(local_err);
1449             goto out;
1450         }
1451     }
1452 
1453     flags = min_sparse ? (BDRV_O_RDWR | BDRV_O_UNMAP) : BDRV_O_RDWR;
1454     ret = bdrv_parse_cache_flags(cache, &flags);
1455     if (ret < 0) {
1456         error_report("Invalid cache option: %s", cache);
1457         goto out;
1458     }
1459 
1460     out_bs = bdrv_new_open("target", out_filename, out_fmt, flags, true, quiet);
1461     if (!out_bs) {
1462         ret = -1;
1463         goto out;
1464     }
1465 
1466     bs_i = 0;
1467     bs_offset = 0;
1468     bdrv_get_geometry(bs[0], &bs_sectors);
1469 
1470     /* increase bufsectors from the default 4096 (2M) if opt_transfer_length
1471      * or discard_alignment of the out_bs is greater. Limit to 32768 (16MB)
1472      * as maximum. */
1473     bufsectors = MIN(32768,
1474                      MAX(bufsectors, MAX(out_bs->bl.opt_transfer_length,
1475                                          out_bs->bl.discard_alignment))
1476                     );
1477 
1478     buf = qemu_blockalign(out_bs, bufsectors * BDRV_SECTOR_SIZE);
1479 
1480     if (skip_create) {
1481         int64_t output_length = bdrv_getlength(out_bs);
1482         if (output_length < 0) {
1483             error_report("unable to get output image length: %s\n",
1484                          strerror(-output_length));
1485             ret = -1;
1486             goto out;
1487         } else if (output_length < total_sectors << BDRV_SECTOR_BITS) {
1488             error_report("output file is smaller than input file");
1489             ret = -1;
1490             goto out;
1491         }
1492     }
1493 
1494     cluster_sectors = 0;
1495     ret = bdrv_get_info(out_bs, &bdi);
1496     if (ret < 0) {
1497         if (compress) {
1498             error_report("could not get block driver info");
1499             goto out;
1500         }
1501     } else {
1502         compress = compress || bdi.needs_compressed_writes;
1503         cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE;
1504     }
1505 
1506     if (compress) {
1507         if (cluster_sectors <= 0 || cluster_sectors > bufsectors) {
1508             error_report("invalid cluster size");
1509             ret = -1;
1510             goto out;
1511         }
1512         sector_num = 0;
1513 
1514         nb_sectors = total_sectors;
1515 
1516         for(;;) {
1517             int64_t bs_num;
1518             int remainder;
1519             uint8_t *buf2;
1520 
1521             nb_sectors = total_sectors - sector_num;
1522             if (nb_sectors <= 0)
1523                 break;
1524             if (nb_sectors >= cluster_sectors)
1525                 n = cluster_sectors;
1526             else
1527                 n = nb_sectors;
1528 
1529             bs_num = sector_num - bs_offset;
1530             assert (bs_num >= 0);
1531             remainder = n;
1532             buf2 = buf;
1533             while (remainder > 0) {
1534                 int nlow;
1535                 while (bs_num == bs_sectors) {
1536                     bs_i++;
1537                     assert (bs_i < bs_n);
1538                     bs_offset += bs_sectors;
1539                     bdrv_get_geometry(bs[bs_i], &bs_sectors);
1540                     bs_num = 0;
1541                     /* printf("changing part: sector_num=%" PRId64 ", "
1542                        "bs_i=%d, bs_offset=%" PRId64 ", bs_sectors=%" PRId64
1543                        "\n", sector_num, bs_i, bs_offset, bs_sectors); */
1544                 }
1545                 assert (bs_num < bs_sectors);
1546 
1547                 nlow = (remainder > bs_sectors - bs_num) ? bs_sectors - bs_num : remainder;
1548 
1549                 ret = bdrv_read(bs[bs_i], bs_num, buf2, nlow);
1550                 if (ret < 0) {
1551                     error_report("error while reading sector %" PRId64 ": %s",
1552                                  bs_num, strerror(-ret));
1553                     goto out;
1554                 }
1555 
1556                 buf2 += nlow * 512;
1557                 bs_num += nlow;
1558 
1559                 remainder -= nlow;
1560             }
1561             assert (remainder == 0);
1562 
1563             if (!buffer_is_zero(buf, n * BDRV_SECTOR_SIZE)) {
1564                 ret = bdrv_write_compressed(out_bs, sector_num, buf, n);
1565                 if (ret != 0) {
1566                     error_report("error while compressing sector %" PRId64
1567                                  ": %s", sector_num, strerror(-ret));
1568                     goto out;
1569                 }
1570             }
1571             sector_num += n;
1572             qemu_progress_print(100.0 * sector_num / total_sectors, 0);
1573         }
1574         /* signal EOF to align */
1575         bdrv_write_compressed(out_bs, 0, NULL, 0);
1576     } else {
1577         int64_t sectors_to_read, sectors_read, sector_num_next_status;
1578         bool count_allocated_sectors;
1579         int has_zero_init = min_sparse ? bdrv_has_zero_init(out_bs) : 0;
1580 
1581         if (!has_zero_init && bdrv_can_write_zeroes_with_unmap(out_bs)) {
1582             ret = bdrv_make_zero(out_bs, BDRV_REQ_MAY_UNMAP);
1583             if (ret < 0) {
1584                 goto out;
1585             }
1586             has_zero_init = 1;
1587         }
1588 
1589         sectors_to_read = total_sectors;
1590         count_allocated_sectors = progress && (out_baseimg || has_zero_init);
1591 restart:
1592         sector_num = 0; // total number of sectors converted so far
1593         sectors_read = 0;
1594         sector_num_next_status = 0;
1595 
1596         for(;;) {
1597             nb_sectors = total_sectors - sector_num;
1598             if (nb_sectors <= 0) {
1599                 if (count_allocated_sectors) {
1600                     sectors_to_read = sectors_read;
1601                     count_allocated_sectors = false;
1602                     goto restart;
1603                 }
1604                 ret = 0;
1605                 break;
1606             }
1607 
1608             while (sector_num - bs_offset >= bs_sectors) {
1609                 bs_i ++;
1610                 assert (bs_i < bs_n);
1611                 bs_offset += bs_sectors;
1612                 bdrv_get_geometry(bs[bs_i], &bs_sectors);
1613                 /* printf("changing part: sector_num=%" PRId64 ", bs_i=%d, "
1614                   "bs_offset=%" PRId64 ", bs_sectors=%" PRId64 "\n",
1615                    sector_num, bs_i, bs_offset, bs_sectors); */
1616             }
1617 
1618             if ((out_baseimg || has_zero_init) &&
1619                 sector_num >= sector_num_next_status) {
1620                 n = nb_sectors > INT_MAX ? INT_MAX : nb_sectors;
1621                 ret = bdrv_get_block_status(bs[bs_i], sector_num - bs_offset,
1622                                             n, &n1);
1623                 if (ret < 0) {
1624                     error_report("error while reading block status of sector %"
1625                                  PRId64 ": %s", sector_num - bs_offset,
1626                                  strerror(-ret));
1627                     goto out;
1628                 }
1629                 /* If the output image is zero initialized, we are not working
1630                  * on a shared base and the input is zero we can skip the next
1631                  * n1 sectors */
1632                 if (has_zero_init && !out_baseimg && (ret & BDRV_BLOCK_ZERO)) {
1633                     sector_num += n1;
1634                     continue;
1635                 }
1636                 /* If the output image is being created as a copy on write
1637                  * image, assume that sectors which are unallocated in the
1638                  * input image are present in both the output's and input's
1639                  * base images (no need to copy them). */
1640                 if (out_baseimg) {
1641                     if (!(ret & BDRV_BLOCK_DATA)) {
1642                         sector_num += n1;
1643                         continue;
1644                     }
1645                     /* The next 'n1' sectors are allocated in the input image.
1646                      * Copy only those as they may be followed by unallocated
1647                      * sectors. */
1648                     nb_sectors = n1;
1649                 }
1650                 /* avoid redundant callouts to get_block_status */
1651                 sector_num_next_status = sector_num + n1;
1652             }
1653 
1654             n = MIN(nb_sectors, bufsectors);
1655 
1656             /* round down request length to an aligned sector, but
1657              * do not bother doing this on short requests. They happen
1658              * when we found an all-zero area, and the next sector to
1659              * write will not be sector_num + n. */
1660             if (cluster_sectors > 0 && n >= cluster_sectors) {
1661                 int64_t next_aligned_sector = (sector_num + n);
1662                 next_aligned_sector -= next_aligned_sector % cluster_sectors;
1663                 if (sector_num + n > next_aligned_sector) {
1664                     n = next_aligned_sector - sector_num;
1665                 }
1666             }
1667 
1668             n = MIN(n, bs_sectors - (sector_num - bs_offset));
1669 
1670             sectors_read += n;
1671             if (count_allocated_sectors) {
1672                 sector_num += n;
1673                 continue;
1674             }
1675 
1676             n1 = n;
1677             ret = bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n);
1678             if (ret < 0) {
1679                 error_report("error while reading sector %" PRId64 ": %s",
1680                              sector_num - bs_offset, strerror(-ret));
1681                 goto out;
1682             }
1683             /* NOTE: at the same time we convert, we do not write zero
1684                sectors to have a chance to compress the image. Ideally, we
1685                should add a specific call to have the info to go faster */
1686             buf1 = buf;
1687             while (n > 0) {
1688                 if (!has_zero_init ||
1689                     is_allocated_sectors_min(buf1, n, &n1, min_sparse)) {
1690                     ret = bdrv_write(out_bs, sector_num, buf1, n1);
1691                     if (ret < 0) {
1692                         error_report("error while writing sector %" PRId64
1693                                      ": %s", sector_num, strerror(-ret));
1694                         goto out;
1695                     }
1696                 }
1697                 sector_num += n1;
1698                 n -= n1;
1699                 buf1 += n1 * 512;
1700             }
1701             qemu_progress_print(100.0 * sectors_read / sectors_to_read, 0);
1702         }
1703     }
1704 out:
1705     if (!ret) {
1706         qemu_progress_print(100, 0);
1707     }
1708     qemu_progress_end();
1709     free_option_parameters(create_options);
1710     free_option_parameters(param);
1711     qemu_vfree(buf);
1712     if (sn_opts) {
1713         qemu_opts_del(sn_opts);
1714     }
1715     if (out_bs) {
1716         bdrv_unref(out_bs);
1717     }
1718     if (bs) {
1719         for (bs_i = 0; bs_i < bs_n; bs_i++) {
1720             if (bs[bs_i]) {
1721                 bdrv_unref(bs[bs_i]);
1722             }
1723         }
1724         g_free(bs);
1725     }
1726 fail_getopt:
1727     g_free(options);
1728 
1729     if (ret) {
1730         return 1;
1731     }
1732     return 0;
1733 }
1734 
1735 
1736 static void dump_snapshots(BlockDriverState *bs)
1737 {
1738     QEMUSnapshotInfo *sn_tab, *sn;
1739     int nb_sns, i;
1740 
1741     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1742     if (nb_sns <= 0)
1743         return;
1744     printf("Snapshot list:\n");
1745     bdrv_snapshot_dump(fprintf, stdout, NULL);
1746     printf("\n");
1747     for(i = 0; i < nb_sns; i++) {
1748         sn = &sn_tab[i];
1749         bdrv_snapshot_dump(fprintf, stdout, sn);
1750         printf("\n");
1751     }
1752     g_free(sn_tab);
1753 }
1754 
1755 static void dump_json_image_info_list(ImageInfoList *list)
1756 {
1757     Error *local_err = NULL;
1758     QString *str;
1759     QmpOutputVisitor *ov = qmp_output_visitor_new();
1760     QObject *obj;
1761     visit_type_ImageInfoList(qmp_output_get_visitor(ov),
1762                              &list, NULL, &local_err);
1763     obj = qmp_output_get_qobject(ov);
1764     str = qobject_to_json_pretty(obj);
1765     assert(str != NULL);
1766     printf("%s\n", qstring_get_str(str));
1767     qobject_decref(obj);
1768     qmp_output_visitor_cleanup(ov);
1769     QDECREF(str);
1770 }
1771 
1772 static void dump_json_image_info(ImageInfo *info)
1773 {
1774     Error *local_err = NULL;
1775     QString *str;
1776     QmpOutputVisitor *ov = qmp_output_visitor_new();
1777     QObject *obj;
1778     visit_type_ImageInfo(qmp_output_get_visitor(ov),
1779                          &info, NULL, &local_err);
1780     obj = qmp_output_get_qobject(ov);
1781     str = qobject_to_json_pretty(obj);
1782     assert(str != NULL);
1783     printf("%s\n", qstring_get_str(str));
1784     qobject_decref(obj);
1785     qmp_output_visitor_cleanup(ov);
1786     QDECREF(str);
1787 }
1788 
1789 static void dump_human_image_info_list(ImageInfoList *list)
1790 {
1791     ImageInfoList *elem;
1792     bool delim = false;
1793 
1794     for (elem = list; elem; elem = elem->next) {
1795         if (delim) {
1796             printf("\n");
1797         }
1798         delim = true;
1799 
1800         bdrv_image_info_dump(fprintf, stdout, elem->value);
1801     }
1802 }
1803 
1804 static gboolean str_equal_func(gconstpointer a, gconstpointer b)
1805 {
1806     return strcmp(a, b) == 0;
1807 }
1808 
1809 /**
1810  * Open an image file chain and return an ImageInfoList
1811  *
1812  * @filename: topmost image filename
1813  * @fmt: topmost image format (may be NULL to autodetect)
1814  * @chain: true  - enumerate entire backing file chain
1815  *         false - only topmost image file
1816  *
1817  * Returns a list of ImageInfo objects or NULL if there was an error opening an
1818  * image file.  If there was an error a message will have been printed to
1819  * stderr.
1820  */
1821 static ImageInfoList *collect_image_info_list(const char *filename,
1822                                               const char *fmt,
1823                                               bool chain)
1824 {
1825     ImageInfoList *head = NULL;
1826     ImageInfoList **last = &head;
1827     GHashTable *filenames;
1828     Error *err = NULL;
1829 
1830     filenames = g_hash_table_new_full(g_str_hash, str_equal_func, NULL, NULL);
1831 
1832     while (filename) {
1833         BlockDriverState *bs;
1834         ImageInfo *info;
1835         ImageInfoList *elem;
1836 
1837         if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
1838             error_report("Backing file '%s' creates an infinite loop.",
1839                          filename);
1840             goto err;
1841         }
1842         g_hash_table_insert(filenames, (gpointer)filename, NULL);
1843 
1844         bs = bdrv_new_open("image", filename, fmt,
1845                            BDRV_O_FLAGS | BDRV_O_NO_BACKING, false, false);
1846         if (!bs) {
1847             goto err;
1848         }
1849 
1850         bdrv_query_image_info(bs, &info, &err);
1851         if (err) {
1852             error_report("%s", error_get_pretty(err));
1853             error_free(err);
1854             bdrv_unref(bs);
1855             goto err;
1856         }
1857 
1858         elem = g_new0(ImageInfoList, 1);
1859         elem->value = info;
1860         *last = elem;
1861         last = &elem->next;
1862 
1863         bdrv_unref(bs);
1864 
1865         filename = fmt = NULL;
1866         if (chain) {
1867             if (info->has_full_backing_filename) {
1868                 filename = info->full_backing_filename;
1869             } else if (info->has_backing_filename) {
1870                 filename = info->backing_filename;
1871             }
1872             if (info->has_backing_filename_format) {
1873                 fmt = info->backing_filename_format;
1874             }
1875         }
1876     }
1877     g_hash_table_destroy(filenames);
1878     return head;
1879 
1880 err:
1881     qapi_free_ImageInfoList(head);
1882     g_hash_table_destroy(filenames);
1883     return NULL;
1884 }
1885 
1886 static int img_info(int argc, char **argv)
1887 {
1888     int c;
1889     OutputFormat output_format = OFORMAT_HUMAN;
1890     bool chain = false;
1891     const char *filename, *fmt, *output;
1892     ImageInfoList *list;
1893 
1894     fmt = NULL;
1895     output = NULL;
1896     for(;;) {
1897         int option_index = 0;
1898         static const struct option long_options[] = {
1899             {"help", no_argument, 0, 'h'},
1900             {"format", required_argument, 0, 'f'},
1901             {"output", required_argument, 0, OPTION_OUTPUT},
1902             {"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
1903             {0, 0, 0, 0}
1904         };
1905         c = getopt_long(argc, argv, "f:h",
1906                         long_options, &option_index);
1907         if (c == -1) {
1908             break;
1909         }
1910         switch(c) {
1911         case '?':
1912         case 'h':
1913             help();
1914             break;
1915         case 'f':
1916             fmt = optarg;
1917             break;
1918         case OPTION_OUTPUT:
1919             output = optarg;
1920             break;
1921         case OPTION_BACKING_CHAIN:
1922             chain = true;
1923             break;
1924         }
1925     }
1926     if (optind != argc - 1) {
1927         error_exit("Expecting one image file name");
1928     }
1929     filename = argv[optind++];
1930 
1931     if (output && !strcmp(output, "json")) {
1932         output_format = OFORMAT_JSON;
1933     } else if (output && !strcmp(output, "human")) {
1934         output_format = OFORMAT_HUMAN;
1935     } else if (output) {
1936         error_report("--output must be used with human or json as argument.");
1937         return 1;
1938     }
1939 
1940     list = collect_image_info_list(filename, fmt, chain);
1941     if (!list) {
1942         return 1;
1943     }
1944 
1945     switch (output_format) {
1946     case OFORMAT_HUMAN:
1947         dump_human_image_info_list(list);
1948         break;
1949     case OFORMAT_JSON:
1950         if (chain) {
1951             dump_json_image_info_list(list);
1952         } else {
1953             dump_json_image_info(list->value);
1954         }
1955         break;
1956     }
1957 
1958     qapi_free_ImageInfoList(list);
1959     return 0;
1960 }
1961 
1962 
1963 typedef struct MapEntry {
1964     int flags;
1965     int depth;
1966     int64_t start;
1967     int64_t length;
1968     int64_t offset;
1969     BlockDriverState *bs;
1970 } MapEntry;
1971 
1972 static void dump_map_entry(OutputFormat output_format, MapEntry *e,
1973                            MapEntry *next)
1974 {
1975     switch (output_format) {
1976     case OFORMAT_HUMAN:
1977         if ((e->flags & BDRV_BLOCK_DATA) &&
1978             !(e->flags & BDRV_BLOCK_OFFSET_VALID)) {
1979             error_report("File contains external, encrypted or compressed clusters.");
1980             exit(1);
1981         }
1982         if ((e->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) == BDRV_BLOCK_DATA) {
1983             printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
1984                    e->start, e->length, e->offset, e->bs->filename);
1985         }
1986         /* This format ignores the distinction between 0, ZERO and ZERO|DATA.
1987          * Modify the flags here to allow more coalescing.
1988          */
1989         if (next &&
1990             (next->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) != BDRV_BLOCK_DATA) {
1991             next->flags &= ~BDRV_BLOCK_DATA;
1992             next->flags |= BDRV_BLOCK_ZERO;
1993         }
1994         break;
1995     case OFORMAT_JSON:
1996         printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64", \"depth\": %d,"
1997                " \"zero\": %s, \"data\": %s",
1998                (e->start == 0 ? "[" : ",\n"),
1999                e->start, e->length, e->depth,
2000                (e->flags & BDRV_BLOCK_ZERO) ? "true" : "false",
2001                (e->flags & BDRV_BLOCK_DATA) ? "true" : "false");
2002         if (e->flags & BDRV_BLOCK_OFFSET_VALID) {
2003             printf(", \"offset\": %"PRId64"", e->offset);
2004         }
2005         putchar('}');
2006 
2007         if (!next) {
2008             printf("]\n");
2009         }
2010         break;
2011     }
2012 }
2013 
2014 static int get_block_status(BlockDriverState *bs, int64_t sector_num,
2015                             int nb_sectors, MapEntry *e)
2016 {
2017     int64_t ret;
2018     int depth;
2019 
2020     /* As an optimization, we could cache the current range of unallocated
2021      * clusters in each file of the chain, and avoid querying the same
2022      * range repeatedly.
2023      */
2024 
2025     depth = 0;
2026     for (;;) {
2027         ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors);
2028         if (ret < 0) {
2029             return ret;
2030         }
2031         assert(nb_sectors);
2032         if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
2033             break;
2034         }
2035         bs = bs->backing_hd;
2036         if (bs == NULL) {
2037             ret = 0;
2038             break;
2039         }
2040 
2041         depth++;
2042     }
2043 
2044     e->start = sector_num * BDRV_SECTOR_SIZE;
2045     e->length = nb_sectors * BDRV_SECTOR_SIZE;
2046     e->flags = ret & ~BDRV_BLOCK_OFFSET_MASK;
2047     e->offset = ret & BDRV_BLOCK_OFFSET_MASK;
2048     e->depth = depth;
2049     e->bs = bs;
2050     return 0;
2051 }
2052 
2053 static int img_map(int argc, char **argv)
2054 {
2055     int c;
2056     OutputFormat output_format = OFORMAT_HUMAN;
2057     BlockDriverState *bs;
2058     const char *filename, *fmt, *output;
2059     int64_t length;
2060     MapEntry curr = { .length = 0 }, next;
2061     int ret = 0;
2062 
2063     fmt = NULL;
2064     output = NULL;
2065     for (;;) {
2066         int option_index = 0;
2067         static const struct option long_options[] = {
2068             {"help", no_argument, 0, 'h'},
2069             {"format", required_argument, 0, 'f'},
2070             {"output", required_argument, 0, OPTION_OUTPUT},
2071             {0, 0, 0, 0}
2072         };
2073         c = getopt_long(argc, argv, "f:h",
2074                         long_options, &option_index);
2075         if (c == -1) {
2076             break;
2077         }
2078         switch (c) {
2079         case '?':
2080         case 'h':
2081             help();
2082             break;
2083         case 'f':
2084             fmt = optarg;
2085             break;
2086         case OPTION_OUTPUT:
2087             output = optarg;
2088             break;
2089         }
2090     }
2091     if (optind != argc - 1) {
2092         error_exit("Expecting one image file name");
2093     }
2094     filename = argv[optind];
2095 
2096     if (output && !strcmp(output, "json")) {
2097         output_format = OFORMAT_JSON;
2098     } else if (output && !strcmp(output, "human")) {
2099         output_format = OFORMAT_HUMAN;
2100     } else if (output) {
2101         error_report("--output must be used with human or json as argument.");
2102         return 1;
2103     }
2104 
2105     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS, true, false);
2106     if (!bs) {
2107         return 1;
2108     }
2109 
2110     if (output_format == OFORMAT_HUMAN) {
2111         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
2112     }
2113 
2114     length = bdrv_getlength(bs);
2115     while (curr.start + curr.length < length) {
2116         int64_t nsectors_left;
2117         int64_t sector_num;
2118         int n;
2119 
2120         sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
2121 
2122         /* Probe up to 1 GiB at a time.  */
2123         nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
2124         n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
2125         ret = get_block_status(bs, sector_num, n, &next);
2126 
2127         if (ret < 0) {
2128             error_report("Could not read file metadata: %s", strerror(-ret));
2129             goto out;
2130         }
2131 
2132         if (curr.length != 0 && curr.flags == next.flags &&
2133             curr.depth == next.depth &&
2134             ((curr.flags & BDRV_BLOCK_OFFSET_VALID) == 0 ||
2135              curr.offset + curr.length == next.offset)) {
2136             curr.length += next.length;
2137             continue;
2138         }
2139 
2140         if (curr.length > 0) {
2141             dump_map_entry(output_format, &curr, &next);
2142         }
2143         curr = next;
2144     }
2145 
2146     dump_map_entry(output_format, &curr, NULL);
2147 
2148 out:
2149     bdrv_unref(bs);
2150     return ret < 0;
2151 }
2152 
2153 #define SNAPSHOT_LIST   1
2154 #define SNAPSHOT_CREATE 2
2155 #define SNAPSHOT_APPLY  3
2156 #define SNAPSHOT_DELETE 4
2157 
2158 static int img_snapshot(int argc, char **argv)
2159 {
2160     BlockDriverState *bs;
2161     QEMUSnapshotInfo sn;
2162     char *filename, *snapshot_name = NULL;
2163     int c, ret = 0, bdrv_oflags;
2164     int action = 0;
2165     qemu_timeval tv;
2166     bool quiet = false;
2167     Error *err = NULL;
2168 
2169     bdrv_oflags = BDRV_O_FLAGS | BDRV_O_RDWR;
2170     /* Parse commandline parameters */
2171     for(;;) {
2172         c = getopt(argc, argv, "la:c:d:hq");
2173         if (c == -1) {
2174             break;
2175         }
2176         switch(c) {
2177         case '?':
2178         case 'h':
2179             help();
2180             return 0;
2181         case 'l':
2182             if (action) {
2183                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2184                 return 0;
2185             }
2186             action = SNAPSHOT_LIST;
2187             bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */
2188             break;
2189         case 'a':
2190             if (action) {
2191                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2192                 return 0;
2193             }
2194             action = SNAPSHOT_APPLY;
2195             snapshot_name = optarg;
2196             break;
2197         case 'c':
2198             if (action) {
2199                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2200                 return 0;
2201             }
2202             action = SNAPSHOT_CREATE;
2203             snapshot_name = optarg;
2204             break;
2205         case 'd':
2206             if (action) {
2207                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2208                 return 0;
2209             }
2210             action = SNAPSHOT_DELETE;
2211             snapshot_name = optarg;
2212             break;
2213         case 'q':
2214             quiet = true;
2215             break;
2216         }
2217     }
2218 
2219     if (optind != argc - 1) {
2220         error_exit("Expecting one image file name");
2221     }
2222     filename = argv[optind++];
2223 
2224     /* Open the image */
2225     bs = bdrv_new_open("image", filename, NULL, bdrv_oflags, true, quiet);
2226     if (!bs) {
2227         return 1;
2228     }
2229 
2230     /* Perform the requested action */
2231     switch(action) {
2232     case SNAPSHOT_LIST:
2233         dump_snapshots(bs);
2234         break;
2235 
2236     case SNAPSHOT_CREATE:
2237         memset(&sn, 0, sizeof(sn));
2238         pstrcpy(sn.name, sizeof(sn.name), snapshot_name);
2239 
2240         qemu_gettimeofday(&tv);
2241         sn.date_sec = tv.tv_sec;
2242         sn.date_nsec = tv.tv_usec * 1000;
2243 
2244         ret = bdrv_snapshot_create(bs, &sn);
2245         if (ret) {
2246             error_report("Could not create snapshot '%s': %d (%s)",
2247                 snapshot_name, ret, strerror(-ret));
2248         }
2249         break;
2250 
2251     case SNAPSHOT_APPLY:
2252         ret = bdrv_snapshot_goto(bs, snapshot_name);
2253         if (ret) {
2254             error_report("Could not apply snapshot '%s': %d (%s)",
2255                 snapshot_name, ret, strerror(-ret));
2256         }
2257         break;
2258 
2259     case SNAPSHOT_DELETE:
2260         bdrv_snapshot_delete_by_id_or_name(bs, snapshot_name, &err);
2261         if (err) {
2262             error_report("Could not delete snapshot '%s': (%s)",
2263                          snapshot_name, error_get_pretty(err));
2264             error_free(err);
2265             ret = 1;
2266         }
2267         break;
2268     }
2269 
2270     /* Cleanup */
2271     bdrv_unref(bs);
2272     if (ret) {
2273         return 1;
2274     }
2275     return 0;
2276 }
2277 
2278 static int img_rebase(int argc, char **argv)
2279 {
2280     BlockDriverState *bs, *bs_old_backing = NULL, *bs_new_backing = NULL;
2281     BlockDriver *old_backing_drv, *new_backing_drv;
2282     char *filename;
2283     const char *fmt, *cache, *out_basefmt, *out_baseimg;
2284     int c, flags, ret;
2285     int unsafe = 0;
2286     int progress = 0;
2287     bool quiet = false;
2288     Error *local_err = NULL;
2289 
2290     /* Parse commandline parameters */
2291     fmt = NULL;
2292     cache = BDRV_DEFAULT_CACHE;
2293     out_baseimg = NULL;
2294     out_basefmt = NULL;
2295     for(;;) {
2296         c = getopt(argc, argv, "uhf:F:b:pt:q");
2297         if (c == -1) {
2298             break;
2299         }
2300         switch(c) {
2301         case '?':
2302         case 'h':
2303             help();
2304             return 0;
2305         case 'f':
2306             fmt = optarg;
2307             break;
2308         case 'F':
2309             out_basefmt = optarg;
2310             break;
2311         case 'b':
2312             out_baseimg = optarg;
2313             break;
2314         case 'u':
2315             unsafe = 1;
2316             break;
2317         case 'p':
2318             progress = 1;
2319             break;
2320         case 't':
2321             cache = optarg;
2322             break;
2323         case 'q':
2324             quiet = true;
2325             break;
2326         }
2327     }
2328 
2329     if (quiet) {
2330         progress = 0;
2331     }
2332 
2333     if (optind != argc - 1) {
2334         error_exit("Expecting one image file name");
2335     }
2336     if (!unsafe && !out_baseimg) {
2337         error_exit("Must specify backing file (-b) or use unsafe mode (-u)");
2338     }
2339     filename = argv[optind++];
2340 
2341     qemu_progress_init(progress, 2.0);
2342     qemu_progress_print(0, 100);
2343 
2344     flags = BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0);
2345     ret = bdrv_parse_cache_flags(cache, &flags);
2346     if (ret < 0) {
2347         error_report("Invalid cache option: %s", cache);
2348         return -1;
2349     }
2350 
2351     /*
2352      * Open the images.
2353      *
2354      * Ignore the old backing file for unsafe rebase in case we want to correct
2355      * the reference to a renamed or moved backing file.
2356      */
2357     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
2358     if (!bs) {
2359         return 1;
2360     }
2361 
2362     /* Find the right drivers for the backing files */
2363     old_backing_drv = NULL;
2364     new_backing_drv = NULL;
2365 
2366     if (!unsafe && bs->backing_format[0] != '\0') {
2367         old_backing_drv = bdrv_find_format(bs->backing_format);
2368         if (old_backing_drv == NULL) {
2369             error_report("Invalid format name: '%s'", bs->backing_format);
2370             ret = -1;
2371             goto out;
2372         }
2373     }
2374 
2375     if (out_basefmt != NULL) {
2376         new_backing_drv = bdrv_find_format(out_basefmt);
2377         if (new_backing_drv == NULL) {
2378             error_report("Invalid format name: '%s'", out_basefmt);
2379             ret = -1;
2380             goto out;
2381         }
2382     }
2383 
2384     /* For safe rebasing we need to compare old and new backing file */
2385     if (unsafe) {
2386         /* Make the compiler happy */
2387         bs_old_backing = NULL;
2388         bs_new_backing = NULL;
2389     } else {
2390         char backing_name[1024];
2391 
2392         bs_old_backing = bdrv_new("old_backing", &error_abort);
2393         bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2394         ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, BDRV_O_FLAGS,
2395                         old_backing_drv, &local_err);
2396         if (ret) {
2397             error_report("Could not open old backing file '%s': %s",
2398                          backing_name, error_get_pretty(local_err));
2399             error_free(local_err);
2400             goto out;
2401         }
2402         if (out_baseimg[0]) {
2403             bs_new_backing = bdrv_new("new_backing", &error_abort);
2404             ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL,
2405                             BDRV_O_FLAGS, new_backing_drv, &local_err);
2406             if (ret) {
2407                 error_report("Could not open new backing file '%s': %s",
2408                              out_baseimg, error_get_pretty(local_err));
2409                 error_free(local_err);
2410                 goto out;
2411             }
2412         }
2413     }
2414 
2415     /*
2416      * Check each unallocated cluster in the COW file. If it is unallocated,
2417      * accesses go to the backing file. We must therefore compare this cluster
2418      * in the old and new backing file, and if they differ we need to copy it
2419      * from the old backing file into the COW file.
2420      *
2421      * If qemu-img crashes during this step, no harm is done. The content of
2422      * the image is the same as the original one at any time.
2423      */
2424     if (!unsafe) {
2425         uint64_t num_sectors;
2426         uint64_t old_backing_num_sectors;
2427         uint64_t new_backing_num_sectors = 0;
2428         uint64_t sector;
2429         int n;
2430         uint8_t * buf_old;
2431         uint8_t * buf_new;
2432         float local_progress = 0;
2433 
2434         buf_old = qemu_blockalign(bs, IO_BUF_SIZE);
2435         buf_new = qemu_blockalign(bs, IO_BUF_SIZE);
2436 
2437         bdrv_get_geometry(bs, &num_sectors);
2438         bdrv_get_geometry(bs_old_backing, &old_backing_num_sectors);
2439         if (bs_new_backing) {
2440             bdrv_get_geometry(bs_new_backing, &new_backing_num_sectors);
2441         }
2442 
2443         if (num_sectors != 0) {
2444             local_progress = (float)100 /
2445                 (num_sectors / MIN(num_sectors, IO_BUF_SIZE / 512));
2446         }
2447 
2448         for (sector = 0; sector < num_sectors; sector += n) {
2449 
2450             /* How many sectors can we handle with the next read? */
2451             if (sector + (IO_BUF_SIZE / 512) <= num_sectors) {
2452                 n = (IO_BUF_SIZE / 512);
2453             } else {
2454                 n = num_sectors - sector;
2455             }
2456 
2457             /* If the cluster is allocated, we don't need to take action */
2458             ret = bdrv_is_allocated(bs, sector, n, &n);
2459             if (ret < 0) {
2460                 error_report("error while reading image metadata: %s",
2461                              strerror(-ret));
2462                 goto out;
2463             }
2464             if (ret) {
2465                 continue;
2466             }
2467 
2468             /*
2469              * Read old and new backing file and take into consideration that
2470              * backing files may be smaller than the COW image.
2471              */
2472             if (sector >= old_backing_num_sectors) {
2473                 memset(buf_old, 0, n * BDRV_SECTOR_SIZE);
2474             } else {
2475                 if (sector + n > old_backing_num_sectors) {
2476                     n = old_backing_num_sectors - sector;
2477                 }
2478 
2479                 ret = bdrv_read(bs_old_backing, sector, buf_old, n);
2480                 if (ret < 0) {
2481                     error_report("error while reading from old backing file");
2482                     goto out;
2483                 }
2484             }
2485 
2486             if (sector >= new_backing_num_sectors || !bs_new_backing) {
2487                 memset(buf_new, 0, n * BDRV_SECTOR_SIZE);
2488             } else {
2489                 if (sector + n > new_backing_num_sectors) {
2490                     n = new_backing_num_sectors - sector;
2491                 }
2492 
2493                 ret = bdrv_read(bs_new_backing, sector, buf_new, n);
2494                 if (ret < 0) {
2495                     error_report("error while reading from new backing file");
2496                     goto out;
2497                 }
2498             }
2499 
2500             /* If they differ, we need to write to the COW file */
2501             uint64_t written = 0;
2502 
2503             while (written < n) {
2504                 int pnum;
2505 
2506                 if (compare_sectors(buf_old + written * 512,
2507                     buf_new + written * 512, n - written, &pnum))
2508                 {
2509                     ret = bdrv_write(bs, sector + written,
2510                         buf_old + written * 512, pnum);
2511                     if (ret < 0) {
2512                         error_report("Error while writing to COW image: %s",
2513                             strerror(-ret));
2514                         goto out;
2515                     }
2516                 }
2517 
2518                 written += pnum;
2519             }
2520             qemu_progress_print(local_progress, 100);
2521         }
2522 
2523         qemu_vfree(buf_old);
2524         qemu_vfree(buf_new);
2525     }
2526 
2527     /*
2528      * Change the backing file. All clusters that are different from the old
2529      * backing file are overwritten in the COW file now, so the visible content
2530      * doesn't change when we switch the backing file.
2531      */
2532     if (out_baseimg && *out_baseimg) {
2533         ret = bdrv_change_backing_file(bs, out_baseimg, out_basefmt);
2534     } else {
2535         ret = bdrv_change_backing_file(bs, NULL, NULL);
2536     }
2537 
2538     if (ret == -ENOSPC) {
2539         error_report("Could not change the backing file to '%s': No "
2540                      "space left in the file header", out_baseimg);
2541     } else if (ret < 0) {
2542         error_report("Could not change the backing file to '%s': %s",
2543             out_baseimg, strerror(-ret));
2544     }
2545 
2546     qemu_progress_print(100, 0);
2547     /*
2548      * TODO At this point it is possible to check if any clusters that are
2549      * allocated in the COW file are the same in the backing file. If so, they
2550      * could be dropped from the COW file. Don't do this before switching the
2551      * backing file, in case of a crash this would lead to corruption.
2552      */
2553 out:
2554     qemu_progress_end();
2555     /* Cleanup */
2556     if (!unsafe) {
2557         if (bs_old_backing != NULL) {
2558             bdrv_unref(bs_old_backing);
2559         }
2560         if (bs_new_backing != NULL) {
2561             bdrv_unref(bs_new_backing);
2562         }
2563     }
2564 
2565     bdrv_unref(bs);
2566     if (ret) {
2567         return 1;
2568     }
2569     return 0;
2570 }
2571 
2572 static int img_resize(int argc, char **argv)
2573 {
2574     int c, ret, relative;
2575     const char *filename, *fmt, *size;
2576     int64_t n, total_size;
2577     bool quiet = false;
2578     BlockDriverState *bs = NULL;
2579     QemuOpts *param;
2580     static QemuOptsList resize_options = {
2581         .name = "resize_options",
2582         .head = QTAILQ_HEAD_INITIALIZER(resize_options.head),
2583         .desc = {
2584             {
2585                 .name = BLOCK_OPT_SIZE,
2586                 .type = QEMU_OPT_SIZE,
2587                 .help = "Virtual disk size"
2588             }, {
2589                 /* end of list */
2590             }
2591         },
2592     };
2593 
2594     /* Remove size from argv manually so that negative numbers are not treated
2595      * as options by getopt. */
2596     if (argc < 3) {
2597         error_exit("Not enough arguments");
2598         return 1;
2599     }
2600 
2601     size = argv[--argc];
2602 
2603     /* Parse getopt arguments */
2604     fmt = NULL;
2605     for(;;) {
2606         c = getopt(argc, argv, "f:hq");
2607         if (c == -1) {
2608             break;
2609         }
2610         switch(c) {
2611         case '?':
2612         case 'h':
2613             help();
2614             break;
2615         case 'f':
2616             fmt = optarg;
2617             break;
2618         case 'q':
2619             quiet = true;
2620             break;
2621         }
2622     }
2623     if (optind != argc - 1) {
2624         error_exit("Expecting one image file name");
2625     }
2626     filename = argv[optind++];
2627 
2628     /* Choose grow, shrink, or absolute resize mode */
2629     switch (size[0]) {
2630     case '+':
2631         relative = 1;
2632         size++;
2633         break;
2634     case '-':
2635         relative = -1;
2636         size++;
2637         break;
2638     default:
2639         relative = 0;
2640         break;
2641     }
2642 
2643     /* Parse size */
2644     param = qemu_opts_create(&resize_options, NULL, 0, &error_abort);
2645     if (qemu_opt_set(param, BLOCK_OPT_SIZE, size)) {
2646         /* Error message already printed when size parsing fails */
2647         ret = -1;
2648         qemu_opts_del(param);
2649         goto out;
2650     }
2651     n = qemu_opt_get_size(param, BLOCK_OPT_SIZE, 0);
2652     qemu_opts_del(param);
2653 
2654     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR,
2655                        true, quiet);
2656     if (!bs) {
2657         ret = -1;
2658         goto out;
2659     }
2660 
2661     if (relative) {
2662         total_size = bdrv_getlength(bs) + n * relative;
2663     } else {
2664         total_size = n;
2665     }
2666     if (total_size <= 0) {
2667         error_report("New image size must be positive");
2668         ret = -1;
2669         goto out;
2670     }
2671 
2672     ret = bdrv_truncate(bs, total_size);
2673     switch (ret) {
2674     case 0:
2675         qprintf(quiet, "Image resized.\n");
2676         break;
2677     case -ENOTSUP:
2678         error_report("This image does not support resize");
2679         break;
2680     case -EACCES:
2681         error_report("Image is read-only");
2682         break;
2683     default:
2684         error_report("Error resizing image (%d)", -ret);
2685         break;
2686     }
2687 out:
2688     if (bs) {
2689         bdrv_unref(bs);
2690     }
2691     if (ret) {
2692         return 1;
2693     }
2694     return 0;
2695 }
2696 
2697 static int img_amend(int argc, char **argv)
2698 {
2699     int c, ret = 0;
2700     char *options = NULL;
2701     QEMUOptionParameter *create_options = NULL, *options_param = NULL;
2702     const char *fmt = NULL, *filename;
2703     bool quiet = false;
2704     BlockDriverState *bs = NULL;
2705 
2706     for (;;) {
2707         c = getopt(argc, argv, "hqf:o:");
2708         if (c == -1) {
2709             break;
2710         }
2711 
2712         switch (c) {
2713             case 'h':
2714             case '?':
2715                 help();
2716                 break;
2717             case 'o':
2718                 if (!is_valid_option_list(optarg)) {
2719                     error_report("Invalid option list: %s", optarg);
2720                     ret = -1;
2721                     goto out;
2722                 }
2723                 if (!options) {
2724                     options = g_strdup(optarg);
2725                 } else {
2726                     char *old_options = options;
2727                     options = g_strdup_printf("%s,%s", options, optarg);
2728                     g_free(old_options);
2729                 }
2730                 break;
2731             case 'f':
2732                 fmt = optarg;
2733                 break;
2734             case 'q':
2735                 quiet = true;
2736                 break;
2737         }
2738     }
2739 
2740     if (!options) {
2741         error_exit("Must specify options (-o)");
2742     }
2743 
2744     filename = (optind == argc - 1) ? argv[argc - 1] : NULL;
2745     if (fmt && has_help_option(options)) {
2746         /* If a format is explicitly specified (and possibly no filename is
2747          * given), print option help here */
2748         ret = print_block_option_help(filename, fmt);
2749         goto out;
2750     }
2751 
2752     if (optind != argc - 1) {
2753         error_exit("Expecting one image file name");
2754     }
2755 
2756     bs = bdrv_new_open("image", filename, fmt,
2757                        BDRV_O_FLAGS | BDRV_O_RDWR, true, quiet);
2758     if (!bs) {
2759         error_report("Could not open image '%s'", filename);
2760         ret = -1;
2761         goto out;
2762     }
2763 
2764     fmt = bs->drv->format_name;
2765 
2766     if (has_help_option(options)) {
2767         /* If the format was auto-detected, print option help here */
2768         ret = print_block_option_help(filename, fmt);
2769         goto out;
2770     }
2771 
2772     create_options = append_option_parameters(create_options,
2773             bs->drv->create_options);
2774     options_param = parse_option_parameters(options, create_options,
2775             options_param);
2776     if (options_param == NULL) {
2777         error_report("Invalid options for file format '%s'", fmt);
2778         ret = -1;
2779         goto out;
2780     }
2781 
2782     ret = bdrv_amend_options(bs, options_param);
2783     if (ret < 0) {
2784         error_report("Error while amending options: %s", strerror(-ret));
2785         goto out;
2786     }
2787 
2788 out:
2789     if (bs) {
2790         bdrv_unref(bs);
2791     }
2792     free_option_parameters(create_options);
2793     free_option_parameters(options_param);
2794     g_free(options);
2795 
2796     if (ret) {
2797         return 1;
2798     }
2799     return 0;
2800 }
2801 
2802 static const img_cmd_t img_cmds[] = {
2803 #define DEF(option, callback, arg_string)        \
2804     { option, callback },
2805 #include "qemu-img-cmds.h"
2806 #undef DEF
2807 #undef GEN_DOCS
2808     { NULL, NULL, },
2809 };
2810 
2811 int main(int argc, char **argv)
2812 {
2813     const img_cmd_t *cmd;
2814     const char *cmdname;
2815     int c;
2816     static const struct option long_options[] = {
2817         {"help", no_argument, 0, 'h'},
2818         {"version", no_argument, 0, 'v'},
2819         {0, 0, 0, 0}
2820     };
2821 
2822 #ifdef CONFIG_POSIX
2823     signal(SIGPIPE, SIG_IGN);
2824 #endif
2825 
2826     error_set_progname(argv[0]);
2827     qemu_init_exec_dir(argv[0]);
2828 
2829     qemu_init_main_loop();
2830     bdrv_init();
2831     if (argc < 2) {
2832         error_exit("Not enough arguments");
2833     }
2834     cmdname = argv[1];
2835 
2836     /* find the command */
2837     for (cmd = img_cmds; cmd->name != NULL; cmd++) {
2838         if (!strcmp(cmdname, cmd->name)) {
2839             return cmd->handler(argc - 1, argv + 1);
2840         }
2841     }
2842 
2843     c = getopt_long(argc, argv, "h", long_options, NULL);
2844 
2845     if (c == 'h') {
2846         help();
2847     }
2848     if (c == 'v') {
2849         printf(QEMU_IMG_VERSION);
2850         return 0;
2851     }
2852 
2853     /* not found */
2854     error_exit("Command not found: %s", cmdname);
2855 }
2856