xref: /openbmc/qemu/qemu-img.c (revision 8f1e884b)
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     if (!g_sequence_lookup(seq, (gpointer)fmt_name,
74                            compare_data, NULL)) {
75         g_sequence_insert_sorted(seq, (gpointer)fmt_name,
76                                  compare_data, NULL);
77     }
78 }
79 
80 static void QEMU_NORETURN GCC_FMT_ATTR(1, 2) error_exit(const char *fmt, ...)
81 {
82     va_list ap;
83 
84     error_printf("qemu-img: ");
85 
86     va_start(ap, fmt);
87     error_vprintf(fmt, ap);
88     va_end(ap);
89 
90     error_printf("\nTry 'qemu-img --help' for more information\n");
91     exit(EXIT_FAILURE);
92 }
93 
94 /* Please keep in synch with qemu-img.texi */
95 static void QEMU_NORETURN help(void)
96 {
97     const char *help_msg =
98            QEMU_IMG_VERSION
99            "usage: qemu-img command [command options]\n"
100            "QEMU disk image utility\n"
101            "\n"
102            "Command syntax:\n"
103 #define DEF(option, callback, arg_string)        \
104            "  " arg_string "\n"
105 #include "qemu-img-cmds.h"
106 #undef DEF
107 #undef GEN_DOCS
108            "\n"
109            "Command parameters:\n"
110            "  'filename' is a disk image filename\n"
111            "  'fmt' is the disk image format. It is guessed automatically in most cases\n"
112            "  'cache' is the cache mode used to write the output disk image, the valid\n"
113            "    options are: 'none', 'writeback' (default, except for convert), 'writethrough',\n"
114            "    'directsync' and 'unsafe' (default for convert)\n"
115            "  'size' is the disk image size in bytes. Optional suffixes\n"
116            "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M),\n"
117            "    'T' (terabyte, 1024G), 'P' (petabyte, 1024T) and 'E' (exabyte, 1024P)  are\n"
118            "    supported. 'b' is ignored.\n"
119            "  'output_filename' is the destination disk image filename\n"
120            "  'output_fmt' is the destination format\n"
121            "  'options' is a comma separated list of format specific options in a\n"
122            "    name=value format. Use -o ? for an overview of the options supported by the\n"
123            "    used format\n"
124            "  'snapshot_param' is param used for internal snapshot, format\n"
125            "    is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
126            "    '[ID_OR_NAME]'\n"
127            "  'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n"
128            "    instead\n"
129            "  '-c' indicates that target image must be compressed (qcow format only)\n"
130            "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"
131            "       match exactly. The image doesn't need a working backing file before\n"
132            "       rebasing in this case (useful for renaming the backing file)\n"
133            "  '-h' with or without a command shows this help and lists the supported formats\n"
134            "  '-p' show progress of command (only certain commands)\n"
135            "  '-q' use Quiet mode - do not print any output (except errors)\n"
136            "  '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
137            "       contain only zeros for qemu-img to create a sparse image during\n"
138            "       conversion. If the number of bytes is 0, the source will not be scanned for\n"
139            "       unallocated or zero sectors, and the destination image will always be\n"
140            "       fully allocated\n"
141            "  '--output' takes the format in which the output must be done (human or json)\n"
142            "  '-n' skips the target volume creation (useful if the volume is created\n"
143            "       prior to running qemu-img)\n"
144            "\n"
145            "Parameters to check subcommand:\n"
146            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
147            "       '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"
148            "       kinds of errors, with a higher risk of choosing the wrong fix or\n"
149            "       hiding corruption that has already occurred.\n"
150            "\n"
151            "Parameters to snapshot subcommand:\n"
152            "  'snapshot' is the name of the snapshot to create, apply or delete\n"
153            "  '-a' applies a snapshot (revert disk to saved state)\n"
154            "  '-c' creates a snapshot\n"
155            "  '-d' deletes a snapshot\n"
156            "  '-l' lists all snapshots in the given image\n"
157            "\n"
158            "Parameters to compare subcommand:\n"
159            "  '-f' first image format\n"
160            "  '-F' second image format\n"
161            "  '-s' run in Strict mode - fail on different image size or sector allocation\n";
162     GSequence *seq;
163 
164     printf("%s\nSupported formats:", help_msg);
165     seq = g_sequence_new(NULL);
166     bdrv_iterate_format(add_format_to_seq, seq);
167     g_sequence_foreach(seq, print_format, NULL);
168     printf("\n");
169     g_sequence_free(seq);
170 
171     exit(EXIT_SUCCESS);
172 }
173 
174 static int GCC_FMT_ATTR(2, 3) qprintf(bool quiet, const char *fmt, ...)
175 {
176     int ret = 0;
177     if (!quiet) {
178         va_list args;
179         va_start(args, fmt);
180         ret = vprintf(fmt, args);
181         va_end(args);
182     }
183     return ret;
184 }
185 
186 #if defined(WIN32)
187 /* XXX: put correct support for win32 */
188 static int read_password(char *buf, int buf_size)
189 {
190     int c, i;
191     printf("Password: ");
192     fflush(stdout);
193     i = 0;
194     for(;;) {
195         c = getchar();
196         if (c == '\n')
197             break;
198         if (i < (buf_size - 1))
199             buf[i++] = c;
200     }
201     buf[i] = '\0';
202     return 0;
203 }
204 
205 #else
206 
207 #include <termios.h>
208 
209 static struct termios oldtty;
210 
211 static void term_exit(void)
212 {
213     tcsetattr (0, TCSANOW, &oldtty);
214 }
215 
216 static void term_init(void)
217 {
218     struct termios tty;
219 
220     tcgetattr (0, &tty);
221     oldtty = tty;
222 
223     tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
224                           |INLCR|IGNCR|ICRNL|IXON);
225     tty.c_oflag |= OPOST;
226     tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
227     tty.c_cflag &= ~(CSIZE|PARENB);
228     tty.c_cflag |= CS8;
229     tty.c_cc[VMIN] = 1;
230     tty.c_cc[VTIME] = 0;
231 
232     tcsetattr (0, TCSANOW, &tty);
233 
234     atexit(term_exit);
235 }
236 
237 static int read_password(char *buf, int buf_size)
238 {
239     uint8_t ch;
240     int i, ret;
241 
242     printf("password: ");
243     fflush(stdout);
244     term_init();
245     i = 0;
246     for(;;) {
247         ret = read(0, &ch, 1);
248         if (ret == -1) {
249             if (errno == EAGAIN || errno == EINTR) {
250                 continue;
251             } else {
252                 ret = -1;
253                 break;
254             }
255         } else if (ret == 0) {
256             ret = -1;
257             break;
258         } else {
259             if (ch == '\r') {
260                 ret = 0;
261                 break;
262             }
263             if (i < (buf_size - 1))
264                 buf[i++] = ch;
265         }
266     }
267     term_exit();
268     buf[i] = '\0';
269     printf("\n");
270     return ret;
271 }
272 #endif
273 
274 static int print_block_option_help(const char *filename, const char *fmt)
275 {
276     BlockDriver *drv, *proto_drv;
277     QEMUOptionParameter *create_options = NULL;
278 
279     /* Find driver and parse its options */
280     drv = bdrv_find_format(fmt);
281     if (!drv) {
282         error_report("Unknown file format '%s'", fmt);
283         return 1;
284     }
285 
286     create_options = append_option_parameters(create_options,
287                                               drv->create_options);
288 
289     if (filename) {
290         proto_drv = bdrv_find_protocol(filename, true);
291         if (!proto_drv) {
292             error_report("Unknown protocol '%s'", filename);
293             return 1;
294         }
295         create_options = append_option_parameters(create_options,
296                                                   proto_drv->create_options);
297     }
298 
299     print_option_help(create_options);
300     free_option_parameters(create_options);
301     return 0;
302 }
303 
304 static BlockDriverState *bdrv_new_open(const char *id,
305                                        const char *filename,
306                                        const char *fmt,
307                                        int flags,
308                                        bool require_io,
309                                        bool quiet)
310 {
311     BlockDriverState *bs;
312     BlockDriver *drv;
313     char password[256];
314     Error *local_err = NULL;
315     int ret;
316 
317     bs = bdrv_new(id, &error_abort);
318 
319     if (fmt) {
320         drv = bdrv_find_format(fmt);
321         if (!drv) {
322             error_report("Unknown file format '%s'", fmt);
323             goto fail;
324         }
325     } else {
326         drv = NULL;
327     }
328 
329     ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err);
330     if (ret < 0) {
331         error_report("Could not open '%s': %s", filename,
332                      error_get_pretty(local_err));
333         error_free(local_err);
334         goto fail;
335     }
336 
337     if (bdrv_is_encrypted(bs) && require_io) {
338         qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);
339         if (read_password(password, sizeof(password)) < 0) {
340             error_report("No password given");
341             goto fail;
342         }
343         if (bdrv_set_key(bs, password) < 0) {
344             error_report("invalid password");
345             goto fail;
346         }
347     }
348     return bs;
349 fail:
350     bdrv_unref(bs);
351     return NULL;
352 }
353 
354 static int add_old_style_options(const char *fmt, QEMUOptionParameter *list,
355                                  const char *base_filename,
356                                  const char *base_fmt)
357 {
358     if (base_filename) {
359         if (set_option_parameter(list, BLOCK_OPT_BACKING_FILE, base_filename)) {
360             error_report("Backing file not supported for file format '%s'",
361                          fmt);
362             return -1;
363         }
364     }
365     if (base_fmt) {
366         if (set_option_parameter(list, BLOCK_OPT_BACKING_FMT, base_fmt)) {
367             error_report("Backing file format not supported for file "
368                          "format '%s'", fmt);
369             return -1;
370         }
371     }
372     return 0;
373 }
374 
375 static int img_create(int argc, char **argv)
376 {
377     int c;
378     uint64_t img_size = -1;
379     const char *fmt = "raw";
380     const char *base_fmt = NULL;
381     const char *filename;
382     const char *base_filename = NULL;
383     char *options = NULL;
384     Error *local_err = NULL;
385     bool quiet = false;
386 
387     for(;;) {
388         c = getopt(argc, argv, "F:b:f:he6o:q");
389         if (c == -1) {
390             break;
391         }
392         switch(c) {
393         case '?':
394         case 'h':
395             help();
396             break;
397         case 'F':
398             base_fmt = optarg;
399             break;
400         case 'b':
401             base_filename = optarg;
402             break;
403         case 'f':
404             fmt = optarg;
405             break;
406         case 'e':
407             error_report("option -e is deprecated, please use \'-o "
408                   "encryption\' instead!");
409             goto fail;
410         case '6':
411             error_report("option -6 is deprecated, please use \'-o "
412                   "compat6\' instead!");
413             goto fail;
414         case 'o':
415             if (!is_valid_option_list(optarg)) {
416                 error_report("Invalid option list: %s", optarg);
417                 goto fail;
418             }
419             if (!options) {
420                 options = g_strdup(optarg);
421             } else {
422                 char *old_options = options;
423                 options = g_strdup_printf("%s,%s", options, optarg);
424                 g_free(old_options);
425             }
426             break;
427         case 'q':
428             quiet = true;
429             break;
430         }
431     }
432 
433     /* Get the filename */
434     filename = (optind < argc) ? argv[optind] : NULL;
435     if (options && has_help_option(options)) {
436         g_free(options);
437         return print_block_option_help(filename, fmt);
438     }
439 
440     if (optind >= argc) {
441         error_exit("Expecting image file name");
442     }
443     optind++;
444 
445     /* Get image size, if specified */
446     if (optind < argc) {
447         int64_t sval;
448         char *end;
449         sval = strtosz_suffix(argv[optind++], &end, STRTOSZ_DEFSUFFIX_B);
450         if (sval < 0 || *end) {
451             if (sval == -ERANGE) {
452                 error_report("Image size must be less than 8 EiB!");
453             } else {
454                 error_report("Invalid image size specified! You may use k, M, "
455                       "G, T, P or E suffixes for ");
456                 error_report("kilobytes, megabytes, gigabytes, terabytes, "
457                              "petabytes and exabytes.");
458             }
459             goto fail;
460         }
461         img_size = (uint64_t)sval;
462     }
463     if (optind != argc) {
464         error_exit("Unexpected argument: %s", argv[optind]);
465     }
466 
467     bdrv_img_create(filename, fmt, base_filename, base_fmt,
468                     options, img_size, BDRV_O_FLAGS, &local_err, quiet);
469     if (local_err) {
470         error_report("%s: %s", filename, error_get_pretty(local_err));
471         error_free(local_err);
472         goto fail;
473     }
474 
475     g_free(options);
476     return 0;
477 
478 fail:
479     g_free(options);
480     return 1;
481 }
482 
483 static void dump_json_image_check(ImageCheck *check, bool quiet)
484 {
485     Error *local_err = NULL;
486     QString *str;
487     QmpOutputVisitor *ov = qmp_output_visitor_new();
488     QObject *obj;
489     visit_type_ImageCheck(qmp_output_get_visitor(ov),
490                           &check, NULL, &local_err);
491     obj = qmp_output_get_qobject(ov);
492     str = qobject_to_json_pretty(obj);
493     assert(str != NULL);
494     qprintf(quiet, "%s\n", qstring_get_str(str));
495     qobject_decref(obj);
496     qmp_output_visitor_cleanup(ov);
497     QDECREF(str);
498 }
499 
500 static void dump_human_image_check(ImageCheck *check, bool quiet)
501 {
502     if (!(check->corruptions || check->leaks || check->check_errors)) {
503         qprintf(quiet, "No errors were found on the image.\n");
504     } else {
505         if (check->corruptions) {
506             qprintf(quiet, "\n%" PRId64 " errors were found on the image.\n"
507                     "Data may be corrupted, or further writes to the image "
508                     "may corrupt it.\n",
509                     check->corruptions);
510         }
511 
512         if (check->leaks) {
513             qprintf(quiet,
514                     "\n%" PRId64 " leaked clusters were found on the image.\n"
515                     "This means waste of disk space, but no harm to data.\n",
516                     check->leaks);
517         }
518 
519         if (check->check_errors) {
520             qprintf(quiet,
521                     "\n%" PRId64
522                     " internal errors have occurred during the check.\n",
523                     check->check_errors);
524         }
525     }
526 
527     if (check->total_clusters != 0 && check->allocated_clusters != 0) {
528         qprintf(quiet, "%" PRId64 "/%" PRId64 " = %0.2f%% allocated, "
529                 "%0.2f%% fragmented, %0.2f%% compressed clusters\n",
530                 check->allocated_clusters, check->total_clusters,
531                 check->allocated_clusters * 100.0 / check->total_clusters,
532                 check->fragmented_clusters * 100.0 / check->allocated_clusters,
533                 check->compressed_clusters * 100.0 /
534                 check->allocated_clusters);
535     }
536 
537     if (check->image_end_offset) {
538         qprintf(quiet,
539                 "Image end offset: %" PRId64 "\n", check->image_end_offset);
540     }
541 }
542 
543 static int collect_image_check(BlockDriverState *bs,
544                    ImageCheck *check,
545                    const char *filename,
546                    const char *fmt,
547                    int fix)
548 {
549     int ret;
550     BdrvCheckResult result;
551 
552     ret = bdrv_check(bs, &result, fix);
553     if (ret < 0) {
554         return ret;
555     }
556 
557     check->filename                 = g_strdup(filename);
558     check->format                   = g_strdup(bdrv_get_format_name(bs));
559     check->check_errors             = result.check_errors;
560     check->corruptions              = result.corruptions;
561     check->has_corruptions          = result.corruptions != 0;
562     check->leaks                    = result.leaks;
563     check->has_leaks                = result.leaks != 0;
564     check->corruptions_fixed        = result.corruptions_fixed;
565     check->has_corruptions_fixed    = result.corruptions != 0;
566     check->leaks_fixed              = result.leaks_fixed;
567     check->has_leaks_fixed          = result.leaks != 0;
568     check->image_end_offset         = result.image_end_offset;
569     check->has_image_end_offset     = result.image_end_offset != 0;
570     check->total_clusters           = result.bfi.total_clusters;
571     check->has_total_clusters       = result.bfi.total_clusters != 0;
572     check->allocated_clusters       = result.bfi.allocated_clusters;
573     check->has_allocated_clusters   = result.bfi.allocated_clusters != 0;
574     check->fragmented_clusters      = result.bfi.fragmented_clusters;
575     check->has_fragmented_clusters  = result.bfi.fragmented_clusters != 0;
576     check->compressed_clusters      = result.bfi.compressed_clusters;
577     check->has_compressed_clusters  = result.bfi.compressed_clusters != 0;
578 
579     return 0;
580 }
581 
582 /*
583  * Checks an image for consistency. Exit codes:
584  *
585  * 0 - Check completed, image is good
586  * 1 - Check not completed because of internal errors
587  * 2 - Check completed, image is corrupted
588  * 3 - Check completed, image has leaked clusters, but is good otherwise
589  */
590 static int img_check(int argc, char **argv)
591 {
592     int c, ret;
593     OutputFormat output_format = OFORMAT_HUMAN;
594     const char *filename, *fmt, *output;
595     BlockDriverState *bs;
596     int fix = 0;
597     int flags = BDRV_O_FLAGS | BDRV_O_CHECK;
598     ImageCheck *check;
599     bool quiet = false;
600 
601     fmt = NULL;
602     output = NULL;
603     for(;;) {
604         int option_index = 0;
605         static const struct option long_options[] = {
606             {"help", no_argument, 0, 'h'},
607             {"format", required_argument, 0, 'f'},
608             {"repair", required_argument, 0, 'r'},
609             {"output", required_argument, 0, OPTION_OUTPUT},
610             {0, 0, 0, 0}
611         };
612         c = getopt_long(argc, argv, "f:hr:q",
613                         long_options, &option_index);
614         if (c == -1) {
615             break;
616         }
617         switch(c) {
618         case '?':
619         case 'h':
620             help();
621             break;
622         case 'f':
623             fmt = optarg;
624             break;
625         case 'r':
626             flags |= BDRV_O_RDWR;
627 
628             if (!strcmp(optarg, "leaks")) {
629                 fix = BDRV_FIX_LEAKS;
630             } else if (!strcmp(optarg, "all")) {
631                 fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS;
632             } else {
633                 error_exit("Unknown option value for -r "
634                            "(expecting 'leaks' or 'all'): %s", optarg);
635             }
636             break;
637         case OPTION_OUTPUT:
638             output = optarg;
639             break;
640         case 'q':
641             quiet = true;
642             break;
643         }
644     }
645     if (optind != argc - 1) {
646         error_exit("Expecting one image file name");
647     }
648     filename = argv[optind++];
649 
650     if (output && !strcmp(output, "json")) {
651         output_format = OFORMAT_JSON;
652     } else if (output && !strcmp(output, "human")) {
653         output_format = OFORMAT_HUMAN;
654     } else if (output) {
655         error_report("--output must be used with human or json as argument.");
656         return 1;
657     }
658 
659     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
660     if (!bs) {
661         return 1;
662     }
663 
664     check = g_new0(ImageCheck, 1);
665     ret = collect_image_check(bs, check, filename, fmt, fix);
666 
667     if (ret == -ENOTSUP) {
668         if (output_format == OFORMAT_HUMAN) {
669             error_report("This image format does not support checks");
670         }
671         ret = 63;
672         goto fail;
673     }
674 
675     if (check->corruptions_fixed || check->leaks_fixed) {
676         int corruptions_fixed, leaks_fixed;
677 
678         leaks_fixed         = check->leaks_fixed;
679         corruptions_fixed   = check->corruptions_fixed;
680 
681         if (output_format == OFORMAT_HUMAN) {
682             qprintf(quiet,
683                     "The following inconsistencies were found and repaired:\n\n"
684                     "    %" PRId64 " leaked clusters\n"
685                     "    %" PRId64 " corruptions\n\n"
686                     "Double checking the fixed image now...\n",
687                     check->leaks_fixed,
688                     check->corruptions_fixed);
689         }
690 
691         ret = collect_image_check(bs, check, filename, fmt, 0);
692 
693         check->leaks_fixed          = leaks_fixed;
694         check->corruptions_fixed    = corruptions_fixed;
695     }
696 
697     switch (output_format) {
698     case OFORMAT_HUMAN:
699         dump_human_image_check(check, quiet);
700         break;
701     case OFORMAT_JSON:
702         dump_json_image_check(check, quiet);
703         break;
704     }
705 
706     if (ret || check->check_errors) {
707         ret = 1;
708         goto fail;
709     }
710 
711     if (check->corruptions) {
712         ret = 2;
713     } else if (check->leaks) {
714         ret = 3;
715     } else {
716         ret = 0;
717     }
718 
719 fail:
720     qapi_free_ImageCheck(check);
721     bdrv_unref(bs);
722 
723     return ret;
724 }
725 
726 static int img_commit(int argc, char **argv)
727 {
728     int c, ret, flags;
729     const char *filename, *fmt, *cache;
730     BlockDriverState *bs;
731     bool quiet = false;
732 
733     fmt = NULL;
734     cache = BDRV_DEFAULT_CACHE;
735     for(;;) {
736         c = getopt(argc, argv, "f:ht:q");
737         if (c == -1) {
738             break;
739         }
740         switch(c) {
741         case '?':
742         case 'h':
743             help();
744             break;
745         case 'f':
746             fmt = optarg;
747             break;
748         case 't':
749             cache = optarg;
750             break;
751         case 'q':
752             quiet = true;
753             break;
754         }
755     }
756     if (optind != argc - 1) {
757         error_exit("Expecting one image file name");
758     }
759     filename = argv[optind++];
760 
761     flags = BDRV_O_RDWR;
762     ret = bdrv_parse_cache_flags(cache, &flags);
763     if (ret < 0) {
764         error_report("Invalid cache option: %s", cache);
765         return -1;
766     }
767 
768     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
769     if (!bs) {
770         return 1;
771     }
772     ret = bdrv_commit(bs);
773     switch(ret) {
774     case 0:
775         qprintf(quiet, "Image committed.\n");
776         break;
777     case -ENOENT:
778         error_report("No disk inserted");
779         break;
780     case -EACCES:
781         error_report("Image is read-only");
782         break;
783     case -ENOTSUP:
784         error_report("Image is already committed");
785         break;
786     default:
787         error_report("Error while committing image");
788         break;
789     }
790 
791     bdrv_unref(bs);
792     if (ret) {
793         return 1;
794     }
795     return 0;
796 }
797 
798 /*
799  * Returns true iff the first sector pointed to by 'buf' contains at least
800  * a non-NUL byte.
801  *
802  * 'pnum' is set to the number of sectors (including and immediately following
803  * the first one) that are known to be in the same allocated/unallocated state.
804  */
805 static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)
806 {
807     bool is_zero;
808     int i;
809 
810     if (n <= 0) {
811         *pnum = 0;
812         return 0;
813     }
814     is_zero = buffer_is_zero(buf, 512);
815     for(i = 1; i < n; i++) {
816         buf += 512;
817         if (is_zero != buffer_is_zero(buf, 512)) {
818             break;
819         }
820     }
821     *pnum = i;
822     return !is_zero;
823 }
824 
825 /*
826  * Like is_allocated_sectors, but if the buffer starts with a used sector,
827  * up to 'min' consecutive sectors containing zeros are ignored. This avoids
828  * breaking up write requests for only small sparse areas.
829  */
830 static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,
831     int min)
832 {
833     int ret;
834     int num_checked, num_used;
835 
836     if (n < min) {
837         min = n;
838     }
839 
840     ret = is_allocated_sectors(buf, n, pnum);
841     if (!ret) {
842         return ret;
843     }
844 
845     num_used = *pnum;
846     buf += BDRV_SECTOR_SIZE * *pnum;
847     n -= *pnum;
848     num_checked = num_used;
849 
850     while (n > 0) {
851         ret = is_allocated_sectors(buf, n, pnum);
852 
853         buf += BDRV_SECTOR_SIZE * *pnum;
854         n -= *pnum;
855         num_checked += *pnum;
856         if (ret) {
857             num_used = num_checked;
858         } else if (*pnum >= min) {
859             break;
860         }
861     }
862 
863     *pnum = num_used;
864     return 1;
865 }
866 
867 /*
868  * Compares two buffers sector by sector. Returns 0 if the first sector of both
869  * buffers matches, non-zero otherwise.
870  *
871  * pnum is set to the number of sectors (including and immediately following
872  * the first one) that are known to have the same comparison result
873  */
874 static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
875     int *pnum)
876 {
877     int res, i;
878 
879     if (n <= 0) {
880         *pnum = 0;
881         return 0;
882     }
883 
884     res = !!memcmp(buf1, buf2, 512);
885     for(i = 1; i < n; i++) {
886         buf1 += 512;
887         buf2 += 512;
888 
889         if (!!memcmp(buf1, buf2, 512) != res) {
890             break;
891         }
892     }
893 
894     *pnum = i;
895     return res;
896 }
897 
898 #define IO_BUF_SIZE (2 * 1024 * 1024)
899 
900 static int64_t sectors_to_bytes(int64_t sectors)
901 {
902     return sectors << BDRV_SECTOR_BITS;
903 }
904 
905 static int64_t sectors_to_process(int64_t total, int64_t from)
906 {
907     return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);
908 }
909 
910 /*
911  * Check if passed sectors are empty (not allocated or contain only 0 bytes)
912  *
913  * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero
914  * data and negative value on error.
915  *
916  * @param bs:  Driver used for accessing file
917  * @param sect_num: Number of first sector to check
918  * @param sect_count: Number of sectors to check
919  * @param filename: Name of disk file we are checking (logging purpose)
920  * @param buffer: Allocated buffer for storing read data
921  * @param quiet: Flag for quiet mode
922  */
923 static int check_empty_sectors(BlockDriverState *bs, int64_t sect_num,
924                                int sect_count, const char *filename,
925                                uint8_t *buffer, bool quiet)
926 {
927     int pnum, ret = 0;
928     ret = bdrv_read(bs, sect_num, buffer, sect_count);
929     if (ret < 0) {
930         error_report("Error while reading offset %" PRId64 " of %s: %s",
931                      sectors_to_bytes(sect_num), filename, strerror(-ret));
932         return ret;
933     }
934     ret = is_allocated_sectors(buffer, sect_count, &pnum);
935     if (ret || pnum != sect_count) {
936         qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
937                 sectors_to_bytes(ret ? sect_num : sect_num + pnum));
938         return 1;
939     }
940 
941     return 0;
942 }
943 
944 /*
945  * Compares two images. Exit codes:
946  *
947  * 0 - Images are identical
948  * 1 - Images differ
949  * >1 - Error occurred
950  */
951 static int img_compare(int argc, char **argv)
952 {
953     const char *fmt1 = NULL, *fmt2 = NULL, *filename1, *filename2;
954     BlockDriverState *bs1, *bs2;
955     int64_t total_sectors1, total_sectors2;
956     uint8_t *buf1 = NULL, *buf2 = NULL;
957     int pnum1, pnum2;
958     int allocated1, allocated2;
959     int ret = 0; /* return value - 0 Ident, 1 Different, >1 Error */
960     bool progress = false, quiet = false, strict = false;
961     int64_t total_sectors;
962     int64_t sector_num = 0;
963     int64_t nb_sectors;
964     int c, pnum;
965     uint64_t bs_sectors;
966     uint64_t progress_base;
967 
968     for (;;) {
969         c = getopt(argc, argv, "hpf:F:sq");
970         if (c == -1) {
971             break;
972         }
973         switch (c) {
974         case '?':
975         case 'h':
976             help();
977             break;
978         case 'f':
979             fmt1 = optarg;
980             break;
981         case 'F':
982             fmt2 = optarg;
983             break;
984         case 'p':
985             progress = true;
986             break;
987         case 'q':
988             quiet = true;
989             break;
990         case 's':
991             strict = true;
992             break;
993         }
994     }
995 
996     /* Progress is not shown in Quiet mode */
997     if (quiet) {
998         progress = false;
999     }
1000 
1001 
1002     if (optind != argc - 2) {
1003         error_exit("Expecting two image file names");
1004     }
1005     filename1 = argv[optind++];
1006     filename2 = argv[optind++];
1007 
1008     /* Initialize before goto out */
1009     qemu_progress_init(progress, 2.0);
1010 
1011     bs1 = bdrv_new_open("image 1", filename1, fmt1, BDRV_O_FLAGS, true, quiet);
1012     if (!bs1) {
1013         error_report("Can't open file %s", filename1);
1014         ret = 2;
1015         goto out3;
1016     }
1017 
1018     bs2 = bdrv_new_open("image 2", filename2, fmt2, BDRV_O_FLAGS, true, quiet);
1019     if (!bs2) {
1020         error_report("Can't open file %s", filename2);
1021         ret = 2;
1022         goto out2;
1023     }
1024 
1025     buf1 = qemu_blockalign(bs1, IO_BUF_SIZE);
1026     buf2 = qemu_blockalign(bs2, IO_BUF_SIZE);
1027     bdrv_get_geometry(bs1, &bs_sectors);
1028     total_sectors1 = bs_sectors;
1029     bdrv_get_geometry(bs2, &bs_sectors);
1030     total_sectors2 = bs_sectors;
1031     total_sectors = MIN(total_sectors1, total_sectors2);
1032     progress_base = MAX(total_sectors1, total_sectors2);
1033 
1034     qemu_progress_print(0, 100);
1035 
1036     if (strict && total_sectors1 != total_sectors2) {
1037         ret = 1;
1038         qprintf(quiet, "Strict mode: Image size mismatch!\n");
1039         goto out;
1040     }
1041 
1042     for (;;) {
1043         nb_sectors = sectors_to_process(total_sectors, sector_num);
1044         if (nb_sectors <= 0) {
1045             break;
1046         }
1047         allocated1 = bdrv_is_allocated_above(bs1, NULL, sector_num, nb_sectors,
1048                                              &pnum1);
1049         if (allocated1 < 0) {
1050             ret = 3;
1051             error_report("Sector allocation test failed for %s", filename1);
1052             goto out;
1053         }
1054 
1055         allocated2 = bdrv_is_allocated_above(bs2, NULL, sector_num, nb_sectors,
1056                                              &pnum2);
1057         if (allocated2 < 0) {
1058             ret = 3;
1059             error_report("Sector allocation test failed for %s", filename2);
1060             goto out;
1061         }
1062         nb_sectors = MIN(pnum1, pnum2);
1063 
1064         if (allocated1 == allocated2) {
1065             if (allocated1) {
1066                 ret = bdrv_read(bs1, sector_num, buf1, nb_sectors);
1067                 if (ret < 0) {
1068                     error_report("Error while reading offset %" PRId64 " of %s:"
1069                                  " %s", sectors_to_bytes(sector_num), filename1,
1070                                  strerror(-ret));
1071                     ret = 4;
1072                     goto out;
1073                 }
1074                 ret = bdrv_read(bs2, sector_num, buf2, nb_sectors);
1075                 if (ret < 0) {
1076                     error_report("Error while reading offset %" PRId64
1077                                  " of %s: %s", sectors_to_bytes(sector_num),
1078                                  filename2, strerror(-ret));
1079                     ret = 4;
1080                     goto out;
1081                 }
1082                 ret = compare_sectors(buf1, buf2, nb_sectors, &pnum);
1083                 if (ret || pnum != nb_sectors) {
1084                     qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
1085                             sectors_to_bytes(
1086                                 ret ? sector_num : sector_num + pnum));
1087                     ret = 1;
1088                     goto out;
1089                 }
1090             }
1091         } else {
1092             if (strict) {
1093                 ret = 1;
1094                 qprintf(quiet, "Strict mode: Offset %" PRId64
1095                         " allocation mismatch!\n",
1096                         sectors_to_bytes(sector_num));
1097                 goto out;
1098             }
1099 
1100             if (allocated1) {
1101                 ret = check_empty_sectors(bs1, sector_num, nb_sectors,
1102                                           filename1, buf1, quiet);
1103             } else {
1104                 ret = check_empty_sectors(bs2, sector_num, nb_sectors,
1105                                           filename2, buf1, quiet);
1106             }
1107             if (ret) {
1108                 if (ret < 0) {
1109                     error_report("Error while reading offset %" PRId64 ": %s",
1110                                  sectors_to_bytes(sector_num), strerror(-ret));
1111                     ret = 4;
1112                 }
1113                 goto out;
1114             }
1115         }
1116         sector_num += nb_sectors;
1117         qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1118     }
1119 
1120     if (total_sectors1 != total_sectors2) {
1121         BlockDriverState *bs_over;
1122         int64_t total_sectors_over;
1123         const char *filename_over;
1124 
1125         qprintf(quiet, "Warning: Image size mismatch!\n");
1126         if (total_sectors1 > total_sectors2) {
1127             total_sectors_over = total_sectors1;
1128             bs_over = bs1;
1129             filename_over = filename1;
1130         } else {
1131             total_sectors_over = total_sectors2;
1132             bs_over = bs2;
1133             filename_over = filename2;
1134         }
1135 
1136         for (;;) {
1137             nb_sectors = sectors_to_process(total_sectors_over, sector_num);
1138             if (nb_sectors <= 0) {
1139                 break;
1140             }
1141             ret = bdrv_is_allocated_above(bs_over, NULL, sector_num,
1142                                           nb_sectors, &pnum);
1143             if (ret < 0) {
1144                 ret = 3;
1145                 error_report("Sector allocation test failed for %s",
1146                              filename_over);
1147                 goto out;
1148 
1149             }
1150             nb_sectors = pnum;
1151             if (ret) {
1152                 ret = check_empty_sectors(bs_over, sector_num, nb_sectors,
1153                                           filename_over, buf1, quiet);
1154                 if (ret) {
1155                     if (ret < 0) {
1156                         error_report("Error while reading offset %" PRId64
1157                                      " of %s: %s", sectors_to_bytes(sector_num),
1158                                      filename_over, strerror(-ret));
1159                         ret = 4;
1160                     }
1161                     goto out;
1162                 }
1163             }
1164             sector_num += nb_sectors;
1165             qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
1166         }
1167     }
1168 
1169     qprintf(quiet, "Images are identical.\n");
1170     ret = 0;
1171 
1172 out:
1173     bdrv_unref(bs2);
1174     qemu_vfree(buf1);
1175     qemu_vfree(buf2);
1176 out2:
1177     bdrv_unref(bs1);
1178 out3:
1179     qemu_progress_end();
1180     return ret;
1181 }
1182 
1183 static int img_convert(int argc, char **argv)
1184 {
1185     int c, n, n1, bs_n, bs_i, compress, cluster_sectors, skip_create;
1186     int64_t ret = 0;
1187     int progress = 0, flags;
1188     const char *fmt, *out_fmt, *cache, *out_baseimg, *out_filename;
1189     BlockDriver *drv, *proto_drv;
1190     BlockDriverState **bs = NULL, *out_bs = NULL;
1191     int64_t total_sectors, nb_sectors, sector_num, bs_offset;
1192     uint64_t bs_sectors;
1193     uint8_t * buf = NULL;
1194     size_t bufsectors = IO_BUF_SIZE / BDRV_SECTOR_SIZE;
1195     const uint8_t *buf1;
1196     BlockDriverInfo bdi;
1197     QEMUOptionParameter *param = NULL, *create_options = NULL;
1198     QEMUOptionParameter *out_baseimg_param;
1199     char *options = NULL;
1200     const char *snapshot_name = NULL;
1201     int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */
1202     bool quiet = false;
1203     Error *local_err = NULL;
1204     QemuOpts *sn_opts = NULL;
1205 
1206     fmt = NULL;
1207     out_fmt = "raw";
1208     cache = "unsafe";
1209     out_baseimg = NULL;
1210     compress = 0;
1211     skip_create = 0;
1212     for(;;) {
1213         c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:qnl:");
1214         if (c == -1) {
1215             break;
1216         }
1217         switch(c) {
1218         case '?':
1219         case 'h':
1220             help();
1221             break;
1222         case 'f':
1223             fmt = optarg;
1224             break;
1225         case 'O':
1226             out_fmt = optarg;
1227             break;
1228         case 'B':
1229             out_baseimg = optarg;
1230             break;
1231         case 'c':
1232             compress = 1;
1233             break;
1234         case 'e':
1235             error_report("option -e is deprecated, please use \'-o "
1236                   "encryption\' instead!");
1237             ret = -1;
1238             goto fail_getopt;
1239         case '6':
1240             error_report("option -6 is deprecated, please use \'-o "
1241                   "compat6\' instead!");
1242             ret = -1;
1243             goto fail_getopt;
1244         case 'o':
1245             if (!is_valid_option_list(optarg)) {
1246                 error_report("Invalid option list: %s", optarg);
1247                 ret = -1;
1248                 goto fail_getopt;
1249             }
1250             if (!options) {
1251                 options = g_strdup(optarg);
1252             } else {
1253                 char *old_options = options;
1254                 options = g_strdup_printf("%s,%s", options, optarg);
1255                 g_free(old_options);
1256             }
1257             break;
1258         case 's':
1259             snapshot_name = optarg;
1260             break;
1261         case 'l':
1262             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
1263                 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0);
1264                 if (!sn_opts) {
1265                     error_report("Failed in parsing snapshot param '%s'",
1266                                  optarg);
1267                     ret = -1;
1268                     goto fail_getopt;
1269                 }
1270             } else {
1271                 snapshot_name = optarg;
1272             }
1273             break;
1274         case 'S':
1275         {
1276             int64_t sval;
1277             char *end;
1278             sval = strtosz_suffix(optarg, &end, STRTOSZ_DEFSUFFIX_B);
1279             if (sval < 0 || *end) {
1280                 error_report("Invalid minimum zero buffer size for sparse output specified");
1281                 ret = -1;
1282                 goto fail_getopt;
1283             }
1284 
1285             min_sparse = sval / BDRV_SECTOR_SIZE;
1286             break;
1287         }
1288         case 'p':
1289             progress = 1;
1290             break;
1291         case 't':
1292             cache = optarg;
1293             break;
1294         case 'q':
1295             quiet = true;
1296             break;
1297         case 'n':
1298             skip_create = 1;
1299             break;
1300         }
1301     }
1302 
1303     /* Initialize before goto out */
1304     if (quiet) {
1305         progress = 0;
1306     }
1307     qemu_progress_init(progress, 1.0);
1308 
1309 
1310     bs_n = argc - optind - 1;
1311     out_filename = bs_n >= 1 ? argv[argc - 1] : NULL;
1312 
1313     if (options && has_help_option(options)) {
1314         ret = print_block_option_help(out_filename, out_fmt);
1315         goto out;
1316     }
1317 
1318     if (bs_n < 1) {
1319         error_exit("Must specify image file name");
1320     }
1321 
1322 
1323     if (bs_n > 1 && out_baseimg) {
1324         error_report("-B makes no sense when concatenating multiple input "
1325                      "images");
1326         ret = -1;
1327         goto out;
1328     }
1329 
1330     qemu_progress_print(0, 100);
1331 
1332     bs = g_malloc0(bs_n * sizeof(BlockDriverState *));
1333 
1334     total_sectors = 0;
1335     for (bs_i = 0; bs_i < bs_n; bs_i++) {
1336         char *id = bs_n > 1 ? g_strdup_printf("source %d", bs_i)
1337                             : g_strdup("source");
1338         bs[bs_i] = bdrv_new_open(id, argv[optind + bs_i], fmt, BDRV_O_FLAGS,
1339                                  true, quiet);
1340         g_free(id);
1341         if (!bs[bs_i]) {
1342             error_report("Could not open '%s'", argv[optind + bs_i]);
1343             ret = -1;
1344             goto out;
1345         }
1346         bdrv_get_geometry(bs[bs_i], &bs_sectors);
1347         total_sectors += bs_sectors;
1348     }
1349 
1350     if (sn_opts) {
1351         ret = bdrv_snapshot_load_tmp(bs[0],
1352                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1353                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1354                                      &local_err);
1355     } else if (snapshot_name != NULL) {
1356         if (bs_n > 1) {
1357             error_report("No support for concatenating multiple snapshot");
1358             ret = -1;
1359             goto out;
1360         }
1361 
1362         bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err);
1363     }
1364     if (local_err) {
1365         error_report("Failed to load snapshot: %s",
1366                      error_get_pretty(local_err));
1367         error_free(local_err);
1368         ret = -1;
1369         goto out;
1370     }
1371 
1372     /* Find driver and parse its options */
1373     drv = bdrv_find_format(out_fmt);
1374     if (!drv) {
1375         error_report("Unknown file format '%s'", out_fmt);
1376         ret = -1;
1377         goto out;
1378     }
1379 
1380     proto_drv = bdrv_find_protocol(out_filename, true);
1381     if (!proto_drv) {
1382         error_report("Unknown protocol '%s'", out_filename);
1383         ret = -1;
1384         goto out;
1385     }
1386 
1387     create_options = append_option_parameters(create_options,
1388                                               drv->create_options);
1389     create_options = append_option_parameters(create_options,
1390                                               proto_drv->create_options);
1391 
1392     if (options) {
1393         param = parse_option_parameters(options, create_options, param);
1394         if (param == NULL) {
1395             error_report("Invalid options for file format '%s'.", out_fmt);
1396             ret = -1;
1397             goto out;
1398         }
1399     } else {
1400         param = parse_option_parameters("", create_options, param);
1401     }
1402 
1403     set_option_parameter_int(param, BLOCK_OPT_SIZE, total_sectors * 512);
1404     ret = add_old_style_options(out_fmt, param, out_baseimg, NULL);
1405     if (ret < 0) {
1406         goto out;
1407     }
1408 
1409     /* Get backing file name if -o backing_file was used */
1410     out_baseimg_param = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
1411     if (out_baseimg_param) {
1412         out_baseimg = out_baseimg_param->value.s;
1413     }
1414 
1415     /* Check if compression is supported */
1416     if (compress) {
1417         QEMUOptionParameter *encryption =
1418             get_option_parameter(param, BLOCK_OPT_ENCRYPT);
1419         QEMUOptionParameter *preallocation =
1420             get_option_parameter(param, BLOCK_OPT_PREALLOC);
1421 
1422         if (!drv->bdrv_write_compressed) {
1423             error_report("Compression not supported for this file format");
1424             ret = -1;
1425             goto out;
1426         }
1427 
1428         if (encryption && encryption->value.n) {
1429             error_report("Compression and encryption not supported at "
1430                          "the same time");
1431             ret = -1;
1432             goto out;
1433         }
1434 
1435         if (preallocation && preallocation->value.s
1436             && strcmp(preallocation->value.s, "off"))
1437         {
1438             error_report("Compression and preallocation not supported at "
1439                          "the same time");
1440             ret = -1;
1441             goto out;
1442         }
1443     }
1444 
1445     if (!skip_create) {
1446         /* Create the new image */
1447         ret = bdrv_create(drv, out_filename, param, &local_err);
1448         if (ret < 0) {
1449             error_report("%s: error while converting %s: %s",
1450                          out_filename, out_fmt, error_get_pretty(local_err));
1451             error_free(local_err);
1452             goto out;
1453         }
1454     }
1455 
1456     flags = min_sparse ? (BDRV_O_RDWR | BDRV_O_UNMAP) : BDRV_O_RDWR;
1457     ret = bdrv_parse_cache_flags(cache, &flags);
1458     if (ret < 0) {
1459         error_report("Invalid cache option: %s", cache);
1460         return -1;
1461     }
1462 
1463     out_bs = bdrv_new_open("target", out_filename, out_fmt, flags, true, quiet);
1464     if (!out_bs) {
1465         ret = -1;
1466         goto out;
1467     }
1468 
1469     bs_i = 0;
1470     bs_offset = 0;
1471     bdrv_get_geometry(bs[0], &bs_sectors);
1472 
1473     /* increase bufsectors from the default 4096 (2M) if opt_transfer_length
1474      * or discard_alignment of the out_bs is greater. Limit to 32768 (16MB)
1475      * as maximum. */
1476     bufsectors = MIN(32768,
1477                      MAX(bufsectors, MAX(out_bs->bl.opt_transfer_length,
1478                                          out_bs->bl.discard_alignment))
1479                     );
1480 
1481     buf = qemu_blockalign(out_bs, bufsectors * BDRV_SECTOR_SIZE);
1482 
1483     if (skip_create) {
1484         int64_t output_length = bdrv_getlength(out_bs);
1485         if (output_length < 0) {
1486             error_report("unable to get output image length: %s\n",
1487                          strerror(-output_length));
1488             ret = -1;
1489             goto out;
1490         } else if (output_length < total_sectors << BDRV_SECTOR_BITS) {
1491             error_report("output file is smaller than input file");
1492             ret = -1;
1493             goto out;
1494         }
1495     }
1496 
1497     cluster_sectors = 0;
1498     ret = bdrv_get_info(out_bs, &bdi);
1499     if (ret < 0) {
1500         if (compress) {
1501             error_report("could not get block driver info");
1502             goto out;
1503         }
1504     } else {
1505         compress = compress || bdi.needs_compressed_writes;
1506         cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE;
1507     }
1508 
1509     if (compress) {
1510         if (cluster_sectors <= 0 || cluster_sectors > bufsectors) {
1511             error_report("invalid cluster size");
1512             ret = -1;
1513             goto out;
1514         }
1515         sector_num = 0;
1516 
1517         nb_sectors = total_sectors;
1518 
1519         for(;;) {
1520             int64_t bs_num;
1521             int remainder;
1522             uint8_t *buf2;
1523 
1524             nb_sectors = total_sectors - sector_num;
1525             if (nb_sectors <= 0)
1526                 break;
1527             if (nb_sectors >= cluster_sectors)
1528                 n = cluster_sectors;
1529             else
1530                 n = nb_sectors;
1531 
1532             bs_num = sector_num - bs_offset;
1533             assert (bs_num >= 0);
1534             remainder = n;
1535             buf2 = buf;
1536             while (remainder > 0) {
1537                 int nlow;
1538                 while (bs_num == bs_sectors) {
1539                     bs_i++;
1540                     assert (bs_i < bs_n);
1541                     bs_offset += bs_sectors;
1542                     bdrv_get_geometry(bs[bs_i], &bs_sectors);
1543                     bs_num = 0;
1544                     /* printf("changing part: sector_num=%" PRId64 ", "
1545                        "bs_i=%d, bs_offset=%" PRId64 ", bs_sectors=%" PRId64
1546                        "\n", sector_num, bs_i, bs_offset, bs_sectors); */
1547                 }
1548                 assert (bs_num < bs_sectors);
1549 
1550                 nlow = (remainder > bs_sectors - bs_num) ? bs_sectors - bs_num : remainder;
1551 
1552                 ret = bdrv_read(bs[bs_i], bs_num, buf2, nlow);
1553                 if (ret < 0) {
1554                     error_report("error while reading sector %" PRId64 ": %s",
1555                                  bs_num, strerror(-ret));
1556                     goto out;
1557                 }
1558 
1559                 buf2 += nlow * 512;
1560                 bs_num += nlow;
1561 
1562                 remainder -= nlow;
1563             }
1564             assert (remainder == 0);
1565 
1566             if (!buffer_is_zero(buf, n * BDRV_SECTOR_SIZE)) {
1567                 ret = bdrv_write_compressed(out_bs, sector_num, buf, n);
1568                 if (ret != 0) {
1569                     error_report("error while compressing sector %" PRId64
1570                                  ": %s", sector_num, strerror(-ret));
1571                     goto out;
1572                 }
1573             }
1574             sector_num += n;
1575             qemu_progress_print(100.0 * sector_num / total_sectors, 0);
1576         }
1577         /* signal EOF to align */
1578         bdrv_write_compressed(out_bs, 0, NULL, 0);
1579     } else {
1580         int64_t sectors_to_read, sectors_read, sector_num_next_status;
1581         bool count_allocated_sectors;
1582         int has_zero_init = min_sparse ? bdrv_has_zero_init(out_bs) : 0;
1583 
1584         if (!has_zero_init && bdrv_can_write_zeroes_with_unmap(out_bs)) {
1585             ret = bdrv_make_zero(out_bs, BDRV_REQ_MAY_UNMAP);
1586             if (ret < 0) {
1587                 goto out;
1588             }
1589             has_zero_init = 1;
1590         }
1591 
1592         sectors_to_read = total_sectors;
1593         count_allocated_sectors = progress && (out_baseimg || has_zero_init);
1594 restart:
1595         sector_num = 0; // total number of sectors converted so far
1596         sectors_read = 0;
1597         sector_num_next_status = 0;
1598 
1599         for(;;) {
1600             nb_sectors = total_sectors - sector_num;
1601             if (nb_sectors <= 0) {
1602                 if (count_allocated_sectors) {
1603                     sectors_to_read = sectors_read;
1604                     count_allocated_sectors = false;
1605                     goto restart;
1606                 }
1607                 ret = 0;
1608                 break;
1609             }
1610 
1611             while (sector_num - bs_offset >= bs_sectors) {
1612                 bs_i ++;
1613                 assert (bs_i < bs_n);
1614                 bs_offset += bs_sectors;
1615                 bdrv_get_geometry(bs[bs_i], &bs_sectors);
1616                 /* printf("changing part: sector_num=%" PRId64 ", bs_i=%d, "
1617                   "bs_offset=%" PRId64 ", bs_sectors=%" PRId64 "\n",
1618                    sector_num, bs_i, bs_offset, bs_sectors); */
1619             }
1620 
1621             if ((out_baseimg || has_zero_init) &&
1622                 sector_num >= sector_num_next_status) {
1623                 n = nb_sectors > INT_MAX ? INT_MAX : nb_sectors;
1624                 ret = bdrv_get_block_status(bs[bs_i], sector_num - bs_offset,
1625                                             n, &n1);
1626                 if (ret < 0) {
1627                     error_report("error while reading block status of sector %"
1628                                  PRId64 ": %s", sector_num - bs_offset,
1629                                  strerror(-ret));
1630                     goto out;
1631                 }
1632                 /* If the output image is zero initialized, we are not working
1633                  * on a shared base and the input is zero we can skip the next
1634                  * n1 sectors */
1635                 if (has_zero_init && !out_baseimg && (ret & BDRV_BLOCK_ZERO)) {
1636                     sector_num += n1;
1637                     continue;
1638                 }
1639                 /* If the output image is being created as a copy on write
1640                  * image, assume that sectors which are unallocated in the
1641                  * input image are present in both the output's and input's
1642                  * base images (no need to copy them). */
1643                 if (out_baseimg) {
1644                     if (!(ret & BDRV_BLOCK_DATA)) {
1645                         sector_num += n1;
1646                         continue;
1647                     }
1648                     /* The next 'n1' sectors are allocated in the input image.
1649                      * Copy only those as they may be followed by unallocated
1650                      * sectors. */
1651                     nb_sectors = n1;
1652                 }
1653                 /* avoid redundant callouts to get_block_status */
1654                 sector_num_next_status = sector_num + n1;
1655             }
1656 
1657             n = MIN(nb_sectors, bufsectors);
1658 
1659             /* round down request length to an aligned sector, but
1660              * do not bother doing this on short requests. They happen
1661              * when we found an all-zero area, and the next sector to
1662              * write will not be sector_num + n. */
1663             if (cluster_sectors > 0 && n >= cluster_sectors) {
1664                 int64_t next_aligned_sector = (sector_num + n);
1665                 next_aligned_sector -= next_aligned_sector % cluster_sectors;
1666                 if (sector_num + n > next_aligned_sector) {
1667                     n = next_aligned_sector - sector_num;
1668                 }
1669             }
1670 
1671             n = MIN(n, bs_sectors - (sector_num - bs_offset));
1672 
1673             sectors_read += n;
1674             if (count_allocated_sectors) {
1675                 sector_num += n;
1676                 continue;
1677             }
1678 
1679             n1 = n;
1680             ret = bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n);
1681             if (ret < 0) {
1682                 error_report("error while reading sector %" PRId64 ": %s",
1683                              sector_num - bs_offset, strerror(-ret));
1684                 goto out;
1685             }
1686             /* NOTE: at the same time we convert, we do not write zero
1687                sectors to have a chance to compress the image. Ideally, we
1688                should add a specific call to have the info to go faster */
1689             buf1 = buf;
1690             while (n > 0) {
1691                 if (!has_zero_init ||
1692                     is_allocated_sectors_min(buf1, n, &n1, min_sparse)) {
1693                     ret = bdrv_write(out_bs, sector_num, buf1, n1);
1694                     if (ret < 0) {
1695                         error_report("error while writing sector %" PRId64
1696                                      ": %s", sector_num, strerror(-ret));
1697                         goto out;
1698                     }
1699                 }
1700                 sector_num += n1;
1701                 n -= n1;
1702                 buf1 += n1 * 512;
1703             }
1704             qemu_progress_print(100.0 * sectors_read / sectors_to_read, 0);
1705         }
1706     }
1707 out:
1708     if (!ret) {
1709         qemu_progress_print(100, 0);
1710     }
1711     qemu_progress_end();
1712     free_option_parameters(create_options);
1713     free_option_parameters(param);
1714     qemu_vfree(buf);
1715     if (sn_opts) {
1716         qemu_opts_del(sn_opts);
1717     }
1718     if (out_bs) {
1719         bdrv_unref(out_bs);
1720     }
1721     if (bs) {
1722         for (bs_i = 0; bs_i < bs_n; bs_i++) {
1723             if (bs[bs_i]) {
1724                 bdrv_unref(bs[bs_i]);
1725             }
1726         }
1727         g_free(bs);
1728     }
1729 fail_getopt:
1730     g_free(options);
1731 
1732     if (ret) {
1733         return 1;
1734     }
1735     return 0;
1736 }
1737 
1738 
1739 static void dump_snapshots(BlockDriverState *bs)
1740 {
1741     QEMUSnapshotInfo *sn_tab, *sn;
1742     int nb_sns, i;
1743 
1744     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1745     if (nb_sns <= 0)
1746         return;
1747     printf("Snapshot list:\n");
1748     bdrv_snapshot_dump(fprintf, stdout, NULL);
1749     printf("\n");
1750     for(i = 0; i < nb_sns; i++) {
1751         sn = &sn_tab[i];
1752         bdrv_snapshot_dump(fprintf, stdout, sn);
1753         printf("\n");
1754     }
1755     g_free(sn_tab);
1756 }
1757 
1758 static void dump_json_image_info_list(ImageInfoList *list)
1759 {
1760     Error *local_err = NULL;
1761     QString *str;
1762     QmpOutputVisitor *ov = qmp_output_visitor_new();
1763     QObject *obj;
1764     visit_type_ImageInfoList(qmp_output_get_visitor(ov),
1765                              &list, NULL, &local_err);
1766     obj = qmp_output_get_qobject(ov);
1767     str = qobject_to_json_pretty(obj);
1768     assert(str != NULL);
1769     printf("%s\n", qstring_get_str(str));
1770     qobject_decref(obj);
1771     qmp_output_visitor_cleanup(ov);
1772     QDECREF(str);
1773 }
1774 
1775 static void dump_json_image_info(ImageInfo *info)
1776 {
1777     Error *local_err = NULL;
1778     QString *str;
1779     QmpOutputVisitor *ov = qmp_output_visitor_new();
1780     QObject *obj;
1781     visit_type_ImageInfo(qmp_output_get_visitor(ov),
1782                          &info, NULL, &local_err);
1783     obj = qmp_output_get_qobject(ov);
1784     str = qobject_to_json_pretty(obj);
1785     assert(str != NULL);
1786     printf("%s\n", qstring_get_str(str));
1787     qobject_decref(obj);
1788     qmp_output_visitor_cleanup(ov);
1789     QDECREF(str);
1790 }
1791 
1792 static void dump_human_image_info_list(ImageInfoList *list)
1793 {
1794     ImageInfoList *elem;
1795     bool delim = false;
1796 
1797     for (elem = list; elem; elem = elem->next) {
1798         if (delim) {
1799             printf("\n");
1800         }
1801         delim = true;
1802 
1803         bdrv_image_info_dump(fprintf, stdout, elem->value);
1804     }
1805 }
1806 
1807 static gboolean str_equal_func(gconstpointer a, gconstpointer b)
1808 {
1809     return strcmp(a, b) == 0;
1810 }
1811 
1812 /**
1813  * Open an image file chain and return an ImageInfoList
1814  *
1815  * @filename: topmost image filename
1816  * @fmt: topmost image format (may be NULL to autodetect)
1817  * @chain: true  - enumerate entire backing file chain
1818  *         false - only topmost image file
1819  *
1820  * Returns a list of ImageInfo objects or NULL if there was an error opening an
1821  * image file.  If there was an error a message will have been printed to
1822  * stderr.
1823  */
1824 static ImageInfoList *collect_image_info_list(const char *filename,
1825                                               const char *fmt,
1826                                               bool chain)
1827 {
1828     ImageInfoList *head = NULL;
1829     ImageInfoList **last = &head;
1830     GHashTable *filenames;
1831     Error *err = NULL;
1832 
1833     filenames = g_hash_table_new_full(g_str_hash, str_equal_func, NULL, NULL);
1834 
1835     while (filename) {
1836         BlockDriverState *bs;
1837         ImageInfo *info;
1838         ImageInfoList *elem;
1839 
1840         if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
1841             error_report("Backing file '%s' creates an infinite loop.",
1842                          filename);
1843             goto err;
1844         }
1845         g_hash_table_insert(filenames, (gpointer)filename, NULL);
1846 
1847         bs = bdrv_new_open("image", filename, fmt,
1848                            BDRV_O_FLAGS | BDRV_O_NO_BACKING, false, false);
1849         if (!bs) {
1850             goto err;
1851         }
1852 
1853         bdrv_query_image_info(bs, &info, &err);
1854         if (err) {
1855             error_report("%s", error_get_pretty(err));
1856             error_free(err);
1857             bdrv_unref(bs);
1858             goto err;
1859         }
1860 
1861         elem = g_new0(ImageInfoList, 1);
1862         elem->value = info;
1863         *last = elem;
1864         last = &elem->next;
1865 
1866         bdrv_unref(bs);
1867 
1868         filename = fmt = NULL;
1869         if (chain) {
1870             if (info->has_full_backing_filename) {
1871                 filename = info->full_backing_filename;
1872             } else if (info->has_backing_filename) {
1873                 filename = info->backing_filename;
1874             }
1875             if (info->has_backing_filename_format) {
1876                 fmt = info->backing_filename_format;
1877             }
1878         }
1879     }
1880     g_hash_table_destroy(filenames);
1881     return head;
1882 
1883 err:
1884     qapi_free_ImageInfoList(head);
1885     g_hash_table_destroy(filenames);
1886     return NULL;
1887 }
1888 
1889 static int img_info(int argc, char **argv)
1890 {
1891     int c;
1892     OutputFormat output_format = OFORMAT_HUMAN;
1893     bool chain = false;
1894     const char *filename, *fmt, *output;
1895     ImageInfoList *list;
1896 
1897     fmt = NULL;
1898     output = NULL;
1899     for(;;) {
1900         int option_index = 0;
1901         static const struct option long_options[] = {
1902             {"help", no_argument, 0, 'h'},
1903             {"format", required_argument, 0, 'f'},
1904             {"output", required_argument, 0, OPTION_OUTPUT},
1905             {"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
1906             {0, 0, 0, 0}
1907         };
1908         c = getopt_long(argc, argv, "f:h",
1909                         long_options, &option_index);
1910         if (c == -1) {
1911             break;
1912         }
1913         switch(c) {
1914         case '?':
1915         case 'h':
1916             help();
1917             break;
1918         case 'f':
1919             fmt = optarg;
1920             break;
1921         case OPTION_OUTPUT:
1922             output = optarg;
1923             break;
1924         case OPTION_BACKING_CHAIN:
1925             chain = true;
1926             break;
1927         }
1928     }
1929     if (optind != argc - 1) {
1930         error_exit("Expecting one image file name");
1931     }
1932     filename = argv[optind++];
1933 
1934     if (output && !strcmp(output, "json")) {
1935         output_format = OFORMAT_JSON;
1936     } else if (output && !strcmp(output, "human")) {
1937         output_format = OFORMAT_HUMAN;
1938     } else if (output) {
1939         error_report("--output must be used with human or json as argument.");
1940         return 1;
1941     }
1942 
1943     list = collect_image_info_list(filename, fmt, chain);
1944     if (!list) {
1945         return 1;
1946     }
1947 
1948     switch (output_format) {
1949     case OFORMAT_HUMAN:
1950         dump_human_image_info_list(list);
1951         break;
1952     case OFORMAT_JSON:
1953         if (chain) {
1954             dump_json_image_info_list(list);
1955         } else {
1956             dump_json_image_info(list->value);
1957         }
1958         break;
1959     }
1960 
1961     qapi_free_ImageInfoList(list);
1962     return 0;
1963 }
1964 
1965 
1966 typedef struct MapEntry {
1967     int flags;
1968     int depth;
1969     int64_t start;
1970     int64_t length;
1971     int64_t offset;
1972     BlockDriverState *bs;
1973 } MapEntry;
1974 
1975 static void dump_map_entry(OutputFormat output_format, MapEntry *e,
1976                            MapEntry *next)
1977 {
1978     switch (output_format) {
1979     case OFORMAT_HUMAN:
1980         if ((e->flags & BDRV_BLOCK_DATA) &&
1981             !(e->flags & BDRV_BLOCK_OFFSET_VALID)) {
1982             error_report("File contains external, encrypted or compressed clusters.");
1983             exit(1);
1984         }
1985         if ((e->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) == BDRV_BLOCK_DATA) {
1986             printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
1987                    e->start, e->length, e->offset, e->bs->filename);
1988         }
1989         /* This format ignores the distinction between 0, ZERO and ZERO|DATA.
1990          * Modify the flags here to allow more coalescing.
1991          */
1992         if (next &&
1993             (next->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) != BDRV_BLOCK_DATA) {
1994             next->flags &= ~BDRV_BLOCK_DATA;
1995             next->flags |= BDRV_BLOCK_ZERO;
1996         }
1997         break;
1998     case OFORMAT_JSON:
1999         printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64", \"depth\": %d,"
2000                " \"zero\": %s, \"data\": %s",
2001                (e->start == 0 ? "[" : ",\n"),
2002                e->start, e->length, e->depth,
2003                (e->flags & BDRV_BLOCK_ZERO) ? "true" : "false",
2004                (e->flags & BDRV_BLOCK_DATA) ? "true" : "false");
2005         if (e->flags & BDRV_BLOCK_OFFSET_VALID) {
2006             printf(", \"offset\": %"PRId64"", e->offset);
2007         }
2008         putchar('}');
2009 
2010         if (!next) {
2011             printf("]\n");
2012         }
2013         break;
2014     }
2015 }
2016 
2017 static int get_block_status(BlockDriverState *bs, int64_t sector_num,
2018                             int nb_sectors, MapEntry *e)
2019 {
2020     int64_t ret;
2021     int depth;
2022 
2023     /* As an optimization, we could cache the current range of unallocated
2024      * clusters in each file of the chain, and avoid querying the same
2025      * range repeatedly.
2026      */
2027 
2028     depth = 0;
2029     for (;;) {
2030         ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors);
2031         if (ret < 0) {
2032             return ret;
2033         }
2034         assert(nb_sectors);
2035         if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
2036             break;
2037         }
2038         bs = bs->backing_hd;
2039         if (bs == NULL) {
2040             ret = 0;
2041             break;
2042         }
2043 
2044         depth++;
2045     }
2046 
2047     e->start = sector_num * BDRV_SECTOR_SIZE;
2048     e->length = nb_sectors * BDRV_SECTOR_SIZE;
2049     e->flags = ret & ~BDRV_BLOCK_OFFSET_MASK;
2050     e->offset = ret & BDRV_BLOCK_OFFSET_MASK;
2051     e->depth = depth;
2052     e->bs = bs;
2053     return 0;
2054 }
2055 
2056 static int img_map(int argc, char **argv)
2057 {
2058     int c;
2059     OutputFormat output_format = OFORMAT_HUMAN;
2060     BlockDriverState *bs;
2061     const char *filename, *fmt, *output;
2062     int64_t length;
2063     MapEntry curr = { .length = 0 }, next;
2064     int ret = 0;
2065 
2066     fmt = NULL;
2067     output = NULL;
2068     for (;;) {
2069         int option_index = 0;
2070         static const struct option long_options[] = {
2071             {"help", no_argument, 0, 'h'},
2072             {"format", required_argument, 0, 'f'},
2073             {"output", required_argument, 0, OPTION_OUTPUT},
2074             {0, 0, 0, 0}
2075         };
2076         c = getopt_long(argc, argv, "f:h",
2077                         long_options, &option_index);
2078         if (c == -1) {
2079             break;
2080         }
2081         switch (c) {
2082         case '?':
2083         case 'h':
2084             help();
2085             break;
2086         case 'f':
2087             fmt = optarg;
2088             break;
2089         case OPTION_OUTPUT:
2090             output = optarg;
2091             break;
2092         }
2093     }
2094     if (optind != argc - 1) {
2095         error_exit("Expecting one image file name");
2096     }
2097     filename = argv[optind];
2098 
2099     if (output && !strcmp(output, "json")) {
2100         output_format = OFORMAT_JSON;
2101     } else if (output && !strcmp(output, "human")) {
2102         output_format = OFORMAT_HUMAN;
2103     } else if (output) {
2104         error_report("--output must be used with human or json as argument.");
2105         return 1;
2106     }
2107 
2108     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS, true, false);
2109     if (!bs) {
2110         return 1;
2111     }
2112 
2113     if (output_format == OFORMAT_HUMAN) {
2114         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
2115     }
2116 
2117     length = bdrv_getlength(bs);
2118     while (curr.start + curr.length < length) {
2119         int64_t nsectors_left;
2120         int64_t sector_num;
2121         int n;
2122 
2123         sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
2124 
2125         /* Probe up to 1 GiB at a time.  */
2126         nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
2127         n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
2128         ret = get_block_status(bs, sector_num, n, &next);
2129 
2130         if (ret < 0) {
2131             error_report("Could not read file metadata: %s", strerror(-ret));
2132             goto out;
2133         }
2134 
2135         if (curr.length != 0 && curr.flags == next.flags &&
2136             curr.depth == next.depth &&
2137             ((curr.flags & BDRV_BLOCK_OFFSET_VALID) == 0 ||
2138              curr.offset + curr.length == next.offset)) {
2139             curr.length += next.length;
2140             continue;
2141         }
2142 
2143         if (curr.length > 0) {
2144             dump_map_entry(output_format, &curr, &next);
2145         }
2146         curr = next;
2147     }
2148 
2149     dump_map_entry(output_format, &curr, NULL);
2150 
2151 out:
2152     bdrv_unref(bs);
2153     return ret < 0;
2154 }
2155 
2156 #define SNAPSHOT_LIST   1
2157 #define SNAPSHOT_CREATE 2
2158 #define SNAPSHOT_APPLY  3
2159 #define SNAPSHOT_DELETE 4
2160 
2161 static int img_snapshot(int argc, char **argv)
2162 {
2163     BlockDriverState *bs;
2164     QEMUSnapshotInfo sn;
2165     char *filename, *snapshot_name = NULL;
2166     int c, ret = 0, bdrv_oflags;
2167     int action = 0;
2168     qemu_timeval tv;
2169     bool quiet = false;
2170     Error *err = NULL;
2171 
2172     bdrv_oflags = BDRV_O_FLAGS | BDRV_O_RDWR;
2173     /* Parse commandline parameters */
2174     for(;;) {
2175         c = getopt(argc, argv, "la:c:d:hq");
2176         if (c == -1) {
2177             break;
2178         }
2179         switch(c) {
2180         case '?':
2181         case 'h':
2182             help();
2183             return 0;
2184         case 'l':
2185             if (action) {
2186                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2187                 return 0;
2188             }
2189             action = SNAPSHOT_LIST;
2190             bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */
2191             break;
2192         case 'a':
2193             if (action) {
2194                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2195                 return 0;
2196             }
2197             action = SNAPSHOT_APPLY;
2198             snapshot_name = optarg;
2199             break;
2200         case 'c':
2201             if (action) {
2202                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2203                 return 0;
2204             }
2205             action = SNAPSHOT_CREATE;
2206             snapshot_name = optarg;
2207             break;
2208         case 'd':
2209             if (action) {
2210                 error_exit("Cannot mix '-l', '-a', '-c', '-d'");
2211                 return 0;
2212             }
2213             action = SNAPSHOT_DELETE;
2214             snapshot_name = optarg;
2215             break;
2216         case 'q':
2217             quiet = true;
2218             break;
2219         }
2220     }
2221 
2222     if (optind != argc - 1) {
2223         error_exit("Expecting one image file name");
2224     }
2225     filename = argv[optind++];
2226 
2227     /* Open the image */
2228     bs = bdrv_new_open("image", filename, NULL, bdrv_oflags, true, quiet);
2229     if (!bs) {
2230         return 1;
2231     }
2232 
2233     /* Perform the requested action */
2234     switch(action) {
2235     case SNAPSHOT_LIST:
2236         dump_snapshots(bs);
2237         break;
2238 
2239     case SNAPSHOT_CREATE:
2240         memset(&sn, 0, sizeof(sn));
2241         pstrcpy(sn.name, sizeof(sn.name), snapshot_name);
2242 
2243         qemu_gettimeofday(&tv);
2244         sn.date_sec = tv.tv_sec;
2245         sn.date_nsec = tv.tv_usec * 1000;
2246 
2247         ret = bdrv_snapshot_create(bs, &sn);
2248         if (ret) {
2249             error_report("Could not create snapshot '%s': %d (%s)",
2250                 snapshot_name, ret, strerror(-ret));
2251         }
2252         break;
2253 
2254     case SNAPSHOT_APPLY:
2255         ret = bdrv_snapshot_goto(bs, snapshot_name);
2256         if (ret) {
2257             error_report("Could not apply snapshot '%s': %d (%s)",
2258                 snapshot_name, ret, strerror(-ret));
2259         }
2260         break;
2261 
2262     case SNAPSHOT_DELETE:
2263         bdrv_snapshot_delete_by_id_or_name(bs, snapshot_name, &err);
2264         if (err) {
2265             error_report("Could not delete snapshot '%s': (%s)",
2266                          snapshot_name, error_get_pretty(err));
2267             error_free(err);
2268             ret = 1;
2269         }
2270         break;
2271     }
2272 
2273     /* Cleanup */
2274     bdrv_unref(bs);
2275     if (ret) {
2276         return 1;
2277     }
2278     return 0;
2279 }
2280 
2281 static int img_rebase(int argc, char **argv)
2282 {
2283     BlockDriverState *bs, *bs_old_backing = NULL, *bs_new_backing = NULL;
2284     BlockDriver *old_backing_drv, *new_backing_drv;
2285     char *filename;
2286     const char *fmt, *cache, *out_basefmt, *out_baseimg;
2287     int c, flags, ret;
2288     int unsafe = 0;
2289     int progress = 0;
2290     bool quiet = false;
2291     Error *local_err = NULL;
2292 
2293     /* Parse commandline parameters */
2294     fmt = NULL;
2295     cache = BDRV_DEFAULT_CACHE;
2296     out_baseimg = NULL;
2297     out_basefmt = NULL;
2298     for(;;) {
2299         c = getopt(argc, argv, "uhf:F:b:pt:q");
2300         if (c == -1) {
2301             break;
2302         }
2303         switch(c) {
2304         case '?':
2305         case 'h':
2306             help();
2307             return 0;
2308         case 'f':
2309             fmt = optarg;
2310             break;
2311         case 'F':
2312             out_basefmt = optarg;
2313             break;
2314         case 'b':
2315             out_baseimg = optarg;
2316             break;
2317         case 'u':
2318             unsafe = 1;
2319             break;
2320         case 'p':
2321             progress = 1;
2322             break;
2323         case 't':
2324             cache = optarg;
2325             break;
2326         case 'q':
2327             quiet = true;
2328             break;
2329         }
2330     }
2331 
2332     if (quiet) {
2333         progress = 0;
2334     }
2335 
2336     if (optind != argc - 1) {
2337         error_exit("Expecting one image file name");
2338     }
2339     if (!unsafe && !out_baseimg) {
2340         error_exit("Must specify backing file (-b) or use unsafe mode (-u)");
2341     }
2342     filename = argv[optind++];
2343 
2344     qemu_progress_init(progress, 2.0);
2345     qemu_progress_print(0, 100);
2346 
2347     flags = BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0);
2348     ret = bdrv_parse_cache_flags(cache, &flags);
2349     if (ret < 0) {
2350         error_report("Invalid cache option: %s", cache);
2351         return -1;
2352     }
2353 
2354     /*
2355      * Open the images.
2356      *
2357      * Ignore the old backing file for unsafe rebase in case we want to correct
2358      * the reference to a renamed or moved backing file.
2359      */
2360     bs = bdrv_new_open("image", filename, fmt, flags, true, quiet);
2361     if (!bs) {
2362         return 1;
2363     }
2364 
2365     /* Find the right drivers for the backing files */
2366     old_backing_drv = NULL;
2367     new_backing_drv = NULL;
2368 
2369     if (!unsafe && bs->backing_format[0] != '\0') {
2370         old_backing_drv = bdrv_find_format(bs->backing_format);
2371         if (old_backing_drv == NULL) {
2372             error_report("Invalid format name: '%s'", bs->backing_format);
2373             ret = -1;
2374             goto out;
2375         }
2376     }
2377 
2378     if (out_basefmt != NULL) {
2379         new_backing_drv = bdrv_find_format(out_basefmt);
2380         if (new_backing_drv == NULL) {
2381             error_report("Invalid format name: '%s'", out_basefmt);
2382             ret = -1;
2383             goto out;
2384         }
2385     }
2386 
2387     /* For safe rebasing we need to compare old and new backing file */
2388     if (unsafe) {
2389         /* Make the compiler happy */
2390         bs_old_backing = NULL;
2391         bs_new_backing = NULL;
2392     } else {
2393         char backing_name[1024];
2394 
2395         bs_old_backing = bdrv_new("old_backing", &error_abort);
2396         bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
2397         ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, BDRV_O_FLAGS,
2398                         old_backing_drv, &local_err);
2399         if (ret) {
2400             error_report("Could not open old backing file '%s': %s",
2401                          backing_name, error_get_pretty(local_err));
2402             error_free(local_err);
2403             goto out;
2404         }
2405         if (out_baseimg[0]) {
2406             bs_new_backing = bdrv_new("new_backing", &error_abort);
2407             ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL,
2408                             BDRV_O_FLAGS, new_backing_drv, &local_err);
2409             if (ret) {
2410                 error_report("Could not open new backing file '%s': %s",
2411                              out_baseimg, error_get_pretty(local_err));
2412                 error_free(local_err);
2413                 goto out;
2414             }
2415         }
2416     }
2417 
2418     /*
2419      * Check each unallocated cluster in the COW file. If it is unallocated,
2420      * accesses go to the backing file. We must therefore compare this cluster
2421      * in the old and new backing file, and if they differ we need to copy it
2422      * from the old backing file into the COW file.
2423      *
2424      * If qemu-img crashes during this step, no harm is done. The content of
2425      * the image is the same as the original one at any time.
2426      */
2427     if (!unsafe) {
2428         uint64_t num_sectors;
2429         uint64_t old_backing_num_sectors;
2430         uint64_t new_backing_num_sectors = 0;
2431         uint64_t sector;
2432         int n;
2433         uint8_t * buf_old;
2434         uint8_t * buf_new;
2435         float local_progress = 0;
2436 
2437         buf_old = qemu_blockalign(bs, IO_BUF_SIZE);
2438         buf_new = qemu_blockalign(bs, IO_BUF_SIZE);
2439 
2440         bdrv_get_geometry(bs, &num_sectors);
2441         bdrv_get_geometry(bs_old_backing, &old_backing_num_sectors);
2442         if (bs_new_backing) {
2443             bdrv_get_geometry(bs_new_backing, &new_backing_num_sectors);
2444         }
2445 
2446         if (num_sectors != 0) {
2447             local_progress = (float)100 /
2448                 (num_sectors / MIN(num_sectors, IO_BUF_SIZE / 512));
2449         }
2450 
2451         for (sector = 0; sector < num_sectors; sector += n) {
2452 
2453             /* How many sectors can we handle with the next read? */
2454             if (sector + (IO_BUF_SIZE / 512) <= num_sectors) {
2455                 n = (IO_BUF_SIZE / 512);
2456             } else {
2457                 n = num_sectors - sector;
2458             }
2459 
2460             /* If the cluster is allocated, we don't need to take action */
2461             ret = bdrv_is_allocated(bs, sector, n, &n);
2462             if (ret < 0) {
2463                 error_report("error while reading image metadata: %s",
2464                              strerror(-ret));
2465                 goto out;
2466             }
2467             if (ret) {
2468                 continue;
2469             }
2470 
2471             /*
2472              * Read old and new backing file and take into consideration that
2473              * backing files may be smaller than the COW image.
2474              */
2475             if (sector >= old_backing_num_sectors) {
2476                 memset(buf_old, 0, n * BDRV_SECTOR_SIZE);
2477             } else {
2478                 if (sector + n > old_backing_num_sectors) {
2479                     n = old_backing_num_sectors - sector;
2480                 }
2481 
2482                 ret = bdrv_read(bs_old_backing, sector, buf_old, n);
2483                 if (ret < 0) {
2484                     error_report("error while reading from old backing file");
2485                     goto out;
2486                 }
2487             }
2488 
2489             if (sector >= new_backing_num_sectors || !bs_new_backing) {
2490                 memset(buf_new, 0, n * BDRV_SECTOR_SIZE);
2491             } else {
2492                 if (sector + n > new_backing_num_sectors) {
2493                     n = new_backing_num_sectors - sector;
2494                 }
2495 
2496                 ret = bdrv_read(bs_new_backing, sector, buf_new, n);
2497                 if (ret < 0) {
2498                     error_report("error while reading from new backing file");
2499                     goto out;
2500                 }
2501             }
2502 
2503             /* If they differ, we need to write to the COW file */
2504             uint64_t written = 0;
2505 
2506             while (written < n) {
2507                 int pnum;
2508 
2509                 if (compare_sectors(buf_old + written * 512,
2510                     buf_new + written * 512, n - written, &pnum))
2511                 {
2512                     ret = bdrv_write(bs, sector + written,
2513                         buf_old + written * 512, pnum);
2514                     if (ret < 0) {
2515                         error_report("Error while writing to COW image: %s",
2516                             strerror(-ret));
2517                         goto out;
2518                     }
2519                 }
2520 
2521                 written += pnum;
2522             }
2523             qemu_progress_print(local_progress, 100);
2524         }
2525 
2526         qemu_vfree(buf_old);
2527         qemu_vfree(buf_new);
2528     }
2529 
2530     /*
2531      * Change the backing file. All clusters that are different from the old
2532      * backing file are overwritten in the COW file now, so the visible content
2533      * doesn't change when we switch the backing file.
2534      */
2535     if (out_baseimg && *out_baseimg) {
2536         ret = bdrv_change_backing_file(bs, out_baseimg, out_basefmt);
2537     } else {
2538         ret = bdrv_change_backing_file(bs, NULL, NULL);
2539     }
2540 
2541     if (ret == -ENOSPC) {
2542         error_report("Could not change the backing file to '%s': No "
2543                      "space left in the file header", out_baseimg);
2544     } else if (ret < 0) {
2545         error_report("Could not change the backing file to '%s': %s",
2546             out_baseimg, strerror(-ret));
2547     }
2548 
2549     qemu_progress_print(100, 0);
2550     /*
2551      * TODO At this point it is possible to check if any clusters that are
2552      * allocated in the COW file are the same in the backing file. If so, they
2553      * could be dropped from the COW file. Don't do this before switching the
2554      * backing file, in case of a crash this would lead to corruption.
2555      */
2556 out:
2557     qemu_progress_end();
2558     /* Cleanup */
2559     if (!unsafe) {
2560         if (bs_old_backing != NULL) {
2561             bdrv_unref(bs_old_backing);
2562         }
2563         if (bs_new_backing != NULL) {
2564             bdrv_unref(bs_new_backing);
2565         }
2566     }
2567 
2568     bdrv_unref(bs);
2569     if (ret) {
2570         return 1;
2571     }
2572     return 0;
2573 }
2574 
2575 static int img_resize(int argc, char **argv)
2576 {
2577     int c, ret, relative;
2578     const char *filename, *fmt, *size;
2579     int64_t n, total_size;
2580     bool quiet = false;
2581     BlockDriverState *bs = NULL;
2582     QemuOpts *param;
2583     static QemuOptsList resize_options = {
2584         .name = "resize_options",
2585         .head = QTAILQ_HEAD_INITIALIZER(resize_options.head),
2586         .desc = {
2587             {
2588                 .name = BLOCK_OPT_SIZE,
2589                 .type = QEMU_OPT_SIZE,
2590                 .help = "Virtual disk size"
2591             }, {
2592                 /* end of list */
2593             }
2594         },
2595     };
2596 
2597     /* Remove size from argv manually so that negative numbers are not treated
2598      * as options by getopt. */
2599     if (argc < 3) {
2600         error_exit("Not enough arguments");
2601         return 1;
2602     }
2603 
2604     size = argv[--argc];
2605 
2606     /* Parse getopt arguments */
2607     fmt = NULL;
2608     for(;;) {
2609         c = getopt(argc, argv, "f:hq");
2610         if (c == -1) {
2611             break;
2612         }
2613         switch(c) {
2614         case '?':
2615         case 'h':
2616             help();
2617             break;
2618         case 'f':
2619             fmt = optarg;
2620             break;
2621         case 'q':
2622             quiet = true;
2623             break;
2624         }
2625     }
2626     if (optind != argc - 1) {
2627         error_exit("Expecting one image file name");
2628     }
2629     filename = argv[optind++];
2630 
2631     /* Choose grow, shrink, or absolute resize mode */
2632     switch (size[0]) {
2633     case '+':
2634         relative = 1;
2635         size++;
2636         break;
2637     case '-':
2638         relative = -1;
2639         size++;
2640         break;
2641     default:
2642         relative = 0;
2643         break;
2644     }
2645 
2646     /* Parse size */
2647     param = qemu_opts_create(&resize_options, NULL, 0, &error_abort);
2648     if (qemu_opt_set(param, BLOCK_OPT_SIZE, size)) {
2649         /* Error message already printed when size parsing fails */
2650         ret = -1;
2651         qemu_opts_del(param);
2652         goto out;
2653     }
2654     n = qemu_opt_get_size(param, BLOCK_OPT_SIZE, 0);
2655     qemu_opts_del(param);
2656 
2657     bs = bdrv_new_open("image", filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR,
2658                        true, quiet);
2659     if (!bs) {
2660         ret = -1;
2661         goto out;
2662     }
2663 
2664     if (relative) {
2665         total_size = bdrv_getlength(bs) + n * relative;
2666     } else {
2667         total_size = n;
2668     }
2669     if (total_size <= 0) {
2670         error_report("New image size must be positive");
2671         ret = -1;
2672         goto out;
2673     }
2674 
2675     ret = bdrv_truncate(bs, total_size);
2676     switch (ret) {
2677     case 0:
2678         qprintf(quiet, "Image resized.\n");
2679         break;
2680     case -ENOTSUP:
2681         error_report("This image does not support resize");
2682         break;
2683     case -EACCES:
2684         error_report("Image is read-only");
2685         break;
2686     default:
2687         error_report("Error resizing image (%d)", -ret);
2688         break;
2689     }
2690 out:
2691     if (bs) {
2692         bdrv_unref(bs);
2693     }
2694     if (ret) {
2695         return 1;
2696     }
2697     return 0;
2698 }
2699 
2700 static int img_amend(int argc, char **argv)
2701 {
2702     int c, ret = 0;
2703     char *options = NULL;
2704     QEMUOptionParameter *create_options = NULL, *options_param = NULL;
2705     const char *fmt = NULL, *filename;
2706     bool quiet = false;
2707     BlockDriverState *bs = NULL;
2708 
2709     for (;;) {
2710         c = getopt(argc, argv, "hqf:o:");
2711         if (c == -1) {
2712             break;
2713         }
2714 
2715         switch (c) {
2716             case 'h':
2717             case '?':
2718                 help();
2719                 break;
2720             case 'o':
2721                 if (!is_valid_option_list(optarg)) {
2722                     error_report("Invalid option list: %s", optarg);
2723                     ret = -1;
2724                     goto out;
2725                 }
2726                 if (!options) {
2727                     options = g_strdup(optarg);
2728                 } else {
2729                     char *old_options = options;
2730                     options = g_strdup_printf("%s,%s", options, optarg);
2731                     g_free(old_options);
2732                 }
2733                 break;
2734             case 'f':
2735                 fmt = optarg;
2736                 break;
2737             case 'q':
2738                 quiet = true;
2739                 break;
2740         }
2741     }
2742 
2743     if (!options) {
2744         error_exit("Must specify options (-o)");
2745     }
2746 
2747     filename = (optind == argc - 1) ? argv[argc - 1] : NULL;
2748     if (fmt && has_help_option(options)) {
2749         /* If a format is explicitly specified (and possibly no filename is
2750          * given), print option help here */
2751         ret = print_block_option_help(filename, fmt);
2752         goto out;
2753     }
2754 
2755     if (optind != argc - 1) {
2756         error_exit("Expecting one image file name");
2757     }
2758 
2759     bs = bdrv_new_open("image", filename, fmt,
2760                        BDRV_O_FLAGS | BDRV_O_RDWR, true, quiet);
2761     if (!bs) {
2762         error_report("Could not open image '%s'", filename);
2763         ret = -1;
2764         goto out;
2765     }
2766 
2767     fmt = bs->drv->format_name;
2768 
2769     if (has_help_option(options)) {
2770         /* If the format was auto-detected, print option help here */
2771         ret = print_block_option_help(filename, fmt);
2772         goto out;
2773     }
2774 
2775     create_options = append_option_parameters(create_options,
2776             bs->drv->create_options);
2777     options_param = parse_option_parameters(options, create_options,
2778             options_param);
2779     if (options_param == NULL) {
2780         error_report("Invalid options for file format '%s'", fmt);
2781         ret = -1;
2782         goto out;
2783     }
2784 
2785     ret = bdrv_amend_options(bs, options_param);
2786     if (ret < 0) {
2787         error_report("Error while amending options: %s", strerror(-ret));
2788         goto out;
2789     }
2790 
2791 out:
2792     if (bs) {
2793         bdrv_unref(bs);
2794     }
2795     free_option_parameters(create_options);
2796     free_option_parameters(options_param);
2797     g_free(options);
2798 
2799     if (ret) {
2800         return 1;
2801     }
2802     return 0;
2803 }
2804 
2805 static const img_cmd_t img_cmds[] = {
2806 #define DEF(option, callback, arg_string)        \
2807     { option, callback },
2808 #include "qemu-img-cmds.h"
2809 #undef DEF
2810 #undef GEN_DOCS
2811     { NULL, NULL, },
2812 };
2813 
2814 int main(int argc, char **argv)
2815 {
2816     const img_cmd_t *cmd;
2817     const char *cmdname;
2818     int c;
2819     static const struct option long_options[] = {
2820         {"help", no_argument, 0, 'h'},
2821         {"version", no_argument, 0, 'v'},
2822         {0, 0, 0, 0}
2823     };
2824 
2825 #ifdef CONFIG_POSIX
2826     signal(SIGPIPE, SIG_IGN);
2827 #endif
2828 
2829     error_set_progname(argv[0]);
2830     qemu_init_exec_dir(argv[0]);
2831 
2832     qemu_init_main_loop();
2833     bdrv_init();
2834     if (argc < 2) {
2835         error_exit("Not enough arguments");
2836     }
2837     cmdname = argv[1];
2838 
2839     /* find the command */
2840     for (cmd = img_cmds; cmd->name != NULL; cmd++) {
2841         if (!strcmp(cmdname, cmd->name)) {
2842             return cmd->handler(argc - 1, argv + 1);
2843         }
2844     }
2845 
2846     c = getopt_long(argc, argv, "h", long_options, NULL);
2847 
2848     if (c == 'h') {
2849         help();
2850     }
2851     if (c == 'v') {
2852         printf(QEMU_IMG_VERSION);
2853         return 0;
2854     }
2855 
2856     /* not found */
2857     error_exit("Command not found: %s", cmdname);
2858 }
2859