btrfs-show-super.c

   1 /*
   2  * Copyright (C) 2012 STRATO AG.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <fcntl.h>
  23 #include <sys/stat.h>
  24 #include <ctype.h>
  25 #include <uuid/uuid.h>
  26 #include <errno.h>
  27
  28 #include "kerncompat.h"
  29 #include "ctree.h"
  30 #include "disk-io.h"
  31 #include "print-tree.h"
  32 #include "transaction.h"
  33 #include "list.h"
  34 #include "utils.h"
  35 #include "crc32c.h"
  36
  37 static void print_usage(void);
  38 static void dump_superblock(struct btrfs_super_block *sb, int full);
  39 int main(int argc, char **argv);
  40 static int load_and_dump_sb(char *, int fd, u64 sb_bytenr, int full, int force);
  41
  42
  43 static void print_usage(void)
  44 {
  45         fprintf(stderr,
  46                 "usage: btrfs-show-super [-i super_mirror|-a|-f|-F] dev [dev..]\n");
  47         fprintf(stderr, "\t-f : print full superblock information\n");
  48         fprintf(stderr, "\t-a : print information of all superblocks\n");
  49         fprintf(stderr, "\t-i <super_mirror> : specify which mirror to print out\n");
  50         fprintf(stderr, "\t-F : attempt to dump superblocks with bad magic\n");
  51         fprintf(stderr, "\t-s <bytenr> : specify alternate superblock offset\n");
  52         fprintf(stderr, "%s\n", PACKAGE_STRING);
  53 }
  54
  55 int main(int argc, char **argv)
  56 {
  57         int opt;
  58         int all = 0;
  59         int full = 0;
  60         int force = 0;
  61         char *filename;
  62         int fd = -1;
  63         int i;
  64         u64 arg;
  65         u64 sb_bytenr = btrfs_sb_offset(0);
  66
  67         while ((opt = getopt(argc, argv, "fFai:s:")) != -1) {
  68                 switch (opt) {
  69                 case 'i':
  70                         arg = arg_strtou64(optarg);
  71                         if (arg >= BTRFS_SUPER_MIRROR_MAX) {
  72                                 fprintf(stderr,
  73                                         "Illegal super_mirror %llu\n",
  74                                         arg);
  75                                 print_usage();
  76                                 exit(1);
  77                         }
  78                         sb_bytenr = btrfs_sb_offset(arg);
  79                         break;
  80
  81                 case 'a':
  82                         all = 1;
  83                         break;
  84                 case 'f':
  85                         full = 1;
  86                         break;
  87                 case 'F':
  88                         force = 1;
  89                         break;
  90                 case 's':
  91                         sb_bytenr = arg_strtou64(optarg);
  92                         all = 0;
  93                         break;
  94                 default:
  95                         print_usage();
  96                         exit(1);
  97                 }
  98         }
  99
 100         set_argv0(argv);
 101         if (check_argc_min(argc - optind, 1)) {
 102                 print_usage();
 103                 exit(1);
 104         }
 105
 106         for (i = optind; i < argc; i++) {
 107                 filename = argv[i];
 108                 fd = open(filename, O_RDONLY, 0666);
 109                 if (fd < 0) {
 110                         fprintf(stderr, "Could not open %s\n", filename);
 111                         exit(1);
 112                 }
 113
 114                 if (all) {
 115                         int idx;
 116                         for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
 117                                 sb_bytenr = btrfs_sb_offset(idx);
 118                                 if (load_and_dump_sb(filename, fd,
 119                                                 sb_bytenr, full, force)) {
 120                                         close(fd);
 121                                         exit(1);
 122                                 }
 123
 124                                 putchar('\n');
 125                         }
 126                 } else {
 127                         load_and_dump_sb(filename, fd, sb_bytenr, full, force);
 128                         putchar('\n');
 129                 }
 130                 close(fd);
 131         }
 132
 133         exit(0);
 134 }
 135
 136 static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full,
 137                 int force)
 138 {
 139         u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
 140         struct btrfs_super_block *sb;
 141         u64 ret;
 142
 143         sb = (struct btrfs_super_block *)super_block_data;
 144
 145         ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
 146         if (ret != BTRFS_SUPER_INFO_SIZE) {
 147                 int e = errno;
 148
 149                 /* check if the disk if too short for further superblock */
 150                 if (ret == 0 && e == 0)
 151                         return 0;
 152
 153                 fprintf(stderr,
 154                    "ERROR: Failed to read the superblock on %s at %llu\n",
 155                    filename, (unsigned long long)sb_bytenr);
 156                 fprintf(stderr,
 157                    "ERROR: error = '%s', errno = %d\n", strerror(e), e);
 158                 return 1;
 159         }
 160         printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
 161         printf("---------------------------------------------------------\n");
 162         if (btrfs_super_magic(sb) != BTRFS_MAGIC && !force) {
 163                 fprintf(stderr,
 164                     "ERROR: bad magic on superblock on %s at %llu\n",
 165                     filename, (unsigned long long)sb_bytenr);
 166         } else {
 167                 dump_superblock(sb, full);
 168         }
 169         return 0;
 170 }
 171
 172 static int check_csum_sblock(void *sb, int csum_size)
 173 {
 174         char result[BTRFS_CSUM_SIZE];
 175         u32 crc = ~(u32)0;
 176
 177         crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
 178                                 crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 179         btrfs_csum_final(crc, result);
 180
 181         return !memcmp(sb, &result, csum_size);
 182 }
 183
 184 static void print_sys_chunk_array(struct btrfs_super_block *sb)
 185 {
 186         struct extent_buffer *buf;
 187         struct btrfs_disk_key *disk_key;
 188         struct btrfs_chunk *chunk;
 189         u8 *array_ptr;
 190         unsigned long sb_array_offset;
 191         u32 num_stripes;
 192         u32 array_size;
 193         u32 len = 0;
 194         u32 cur_offset;
 195         struct btrfs_key key;
 196         int item;
 197
 198         buf = malloc(sizeof(*buf) + sizeof(*sb));
 199         if (!buf) {
 200                 fprintf(stderr, "%s\n", strerror(ENOMEM));
 201                 exit(1);
 202         }
 203         write_extent_buffer(buf, sb, 0, sizeof(*sb));
 204         array_size = btrfs_super_sys_array_size(sb);
 205
 206         array_ptr = sb->sys_chunk_array;
 207         sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
 208         cur_offset = 0;
 209         item = 0;
 210
 211         while (cur_offset < array_size) {
 212                 disk_key = (struct btrfs_disk_key *)array_ptr;
 213                 len = sizeof(*disk_key);
 214                 if (cur_offset + len > array_size)
 215                         goto out_short_read;
 216
 217                 btrfs_disk_key_to_cpu(&key, disk_key);
 218
 219                 array_ptr += len;
 220                 sb_array_offset += len;
 221                 cur_offset += len;
 222
 223                 printf("\titem %d ", item);
 224                 btrfs_print_key(disk_key);
 225                 putchar('\n');
 226
 227                 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
 228                         chunk = (struct btrfs_chunk *)sb_array_offset;
 229                         /*
 230                          * At least one btrfs_chunk with one stripe must be
 231                          * present, exact stripe count check comes afterwards
 232                          */
 233                         len = btrfs_chunk_item_size(1);
 234                         if (cur_offset + len > array_size)
 235                                 goto out_short_read;
 236
 237                         print_chunk(buf, chunk);
 238                         num_stripes = btrfs_chunk_num_stripes(buf, chunk);
 239                         if (!num_stripes) {
 240                                 printk(
 241             "ERROR: invalid number of stripes %u in sys_array at offset %u\n",
 242                                         num_stripes, cur_offset);
 243                                 break;
 244                         }
 245                         len = btrfs_chunk_item_size(num_stripes);
 246                         if (cur_offset + len > array_size)
 247                                 goto out_short_read;
 248                 } else {
 249                         printk(
 250                 "ERROR: unexpected item type %u in sys_array at offset %u\n",
 251                                 (u32)key.type, cur_offset);
 252                         break;
 253                 }
 254                 array_ptr += len;
 255                 sb_array_offset += len;
 256                 cur_offset += len;
 257
 258                 item++;
 259         }
 260
 261         free(buf);
 262         return;
 263
 264 out_short_read:
 265         printk("ERROR: sys_array too short to read %u bytes at offset %u\n",
 266                         len, cur_offset);
 267         free(buf);
 268 }
 269
 270 static int empty_backup(struct btrfs_root_backup *backup)
 271 {
 272         if (backup == NULL ||
 273                 (backup->tree_root == 0 &&
 274                  backup->tree_root_gen == 0))
 275                 return 1;
 276         return 0;
 277 }
 278
 279 static void print_root_backup(struct btrfs_root_backup *backup)
 280 {
 281         printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
 282                         btrfs_backup_tree_root(backup),
 283                         btrfs_backup_tree_root_gen(backup),
 284                         btrfs_backup_tree_root_level(backup));
 285         printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
 286                         btrfs_backup_chunk_root(backup),
 287                         btrfs_backup_chunk_root_gen(backup),
 288                         btrfs_backup_chunk_root_level(backup));
 289         printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
 290                         btrfs_backup_extent_root(backup),
 291                         btrfs_backup_extent_root_gen(backup),
 292                         btrfs_backup_extent_root_level(backup));
 293         printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
 294                         btrfs_backup_fs_root(backup),
 295                         btrfs_backup_fs_root_gen(backup),
 296                         btrfs_backup_fs_root_level(backup));
 297         printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
 298                         btrfs_backup_dev_root(backup),
 299                         btrfs_backup_dev_root_gen(backup),
 300                         btrfs_backup_dev_root_level(backup));
 301         printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
 302                         btrfs_backup_csum_root(backup),
 303                         btrfs_backup_csum_root_gen(backup),
 304                         btrfs_backup_csum_root_level(backup));
 305
 306         printf("\t\tbackup_total_bytes:\t%llu\n",
 307                                         btrfs_backup_total_bytes(backup));
 308         printf("\t\tbackup_bytes_used:\t%llu\n",
 309                                         btrfs_backup_bytes_used(backup));
 310         printf("\t\tbackup_num_devices:\t%llu\n",
 311                                         btrfs_backup_num_devices(backup));
 312         putchar('\n');
 313 }
 314
 315 static void print_backup_roots(struct btrfs_super_block *sb)
 316 {
 317         struct btrfs_root_backup *backup;
 318         int i;
 319
 320         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
 321                 backup = sb->super_roots + i;
 322                 if (!empty_backup(backup)) {
 323                         printf("\tbackup %d:\n", i);
 324                         print_root_backup(backup);
 325                 }
 326         }
 327 }
 328
 329 struct readable_flag_entry {
 330         u64 bit;
 331         char *output;
 332 };
 333
 334 #define DEF_INCOMPAT_FLAG_ENTRY(bit_name)               \
 335         {BTRFS_FEATURE_INCOMPAT_##bit_name, #bit_name}
 336
 337 static struct readable_flag_entry incompat_flags_array[] = {
 338         DEF_INCOMPAT_FLAG_ENTRY(MIXED_BACKREF),
 339         DEF_INCOMPAT_FLAG_ENTRY(DEFAULT_SUBVOL),
 340         DEF_INCOMPAT_FLAG_ENTRY(MIXED_GROUPS),
 341         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZO),
 342         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZOv2),
 343         DEF_INCOMPAT_FLAG_ENTRY(BIG_METADATA),
 344         DEF_INCOMPAT_FLAG_ENTRY(EXTENDED_IREF),
 345         DEF_INCOMPAT_FLAG_ENTRY(RAID56),
 346         DEF_INCOMPAT_FLAG_ENTRY(SKINNY_METADATA),
 347         DEF_INCOMPAT_FLAG_ENTRY(NO_HOLES)
 348 };
 349 static const int incompat_flags_num = sizeof(incompat_flags_array) /
 350                                       sizeof(struct readable_flag_entry);
 351
 352 #define DEF_HEADER_FLAG_ENTRY(bit_name)                 \
 353         {BTRFS_HEADER_FLAG_##bit_name, #bit_name}
 354 #define DEF_SUPER_FLAG_ENTRY(bit_name)                  \
 355         {BTRFS_SUPER_FLAG_##bit_name, #bit_name}
 356
 357 static struct readable_flag_entry super_flags_array[] = {
 358         DEF_HEADER_FLAG_ENTRY(WRITTEN),
 359         DEF_HEADER_FLAG_ENTRY(RELOC),
 360         DEF_SUPER_FLAG_ENTRY(CHANGING_FSID),
 361         DEF_SUPER_FLAG_ENTRY(SEEDING),
 362         DEF_SUPER_FLAG_ENTRY(METADUMP),
 363         DEF_SUPER_FLAG_ENTRY(METADUMP_V2)
 364 };
 365 static const int super_flags_num = ARRAY_SIZE(super_flags_array);
 366
 367 #define BTRFS_SUPER_FLAG_SUPP   (BTRFS_HEADER_FLAG_WRITTEN |\
 368                                  BTRFS_HEADER_FLAG_RELOC |\
 369                                  BTRFS_SUPER_FLAG_CHANGING_FSID |\
 370                                  BTRFS_SUPER_FLAG_SEEDING |\
 371                                  BTRFS_SUPER_FLAG_METADUMP |\
 372                                  BTRFS_SUPER_FLAG_METADUMP_V2)
 373
 374 static void __print_readable_flag(u64 flag, struct readable_flag_entry *array,
 375                                   int array_size, u64 supported_flags)
 376 {
 377         int i;
 378         int first = 1;
 379         struct readable_flag_entry *entry;
 380
 381         if (!flag)
 382                 return;
 383
 384         printf("\t\t\t( ");
 385         for (i = 0; i < array_size; i++) {
 386                 entry = array + i;
 387                 if (flag & entry->bit) {
 388                         if (first)
 389                                 printf("%s ", entry->output);
 390                         else
 391                                 printf("|\n\t\t\t  %s ", entry->output);
 392                         first = 0;
 393                 }
 394         }
 395         flag &= ~supported_flags;
 396         if (flag) {
 397                 if (first)
 398                         printf("unknown flag: 0x%llx ", flag);
 399                 else
 400                         printf("|\n\t\t\t  unknown flag: 0x%llx ", flag);
 401         }
 402         printf(")\n");
 403 }
 404
 405 static void print_readable_incompat_flag(u64 flag)
 406 {
 407         return __print_readable_flag(flag, incompat_flags_array,
 408                                      incompat_flags_num,
 409                                      BTRFS_FEATURE_INCOMPAT_SUPP);
 410 }
 411
 412 static void print_readable_super_flag(u64 flag)
 413 {
 414         return __print_readable_flag(flag, super_flags_array,
 415                                      super_flags_num, BTRFS_SUPER_FLAG_SUPP);
 416 }
 417
 418 static void dump_superblock(struct btrfs_super_block *sb, int full)
 419 {
 420         int i;
 421         char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
 422         u8 *p;
 423
 424         printf("csum\t\t\t0x");
 425         for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)
 426                 printf("%02x", p[i]);
 427         if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
 428                 printf(" [match]");
 429         else
 430                 printf(" [DON'T MATCH]");
 431         putchar('\n');
 432
 433         printf("bytenr\t\t\t%llu\n",
 434                 (unsigned long long)btrfs_super_bytenr(sb));
 435         printf("flags\t\t\t0x%llx\n",
 436                 (unsigned long long)btrfs_super_flags(sb));
 437         print_readable_super_flag(btrfs_super_flags(sb));
 438
 439         printf("magic\t\t\t");
 440         s = (char *) &sb->magic;
 441         for (i = 0; i < 8; i++)
 442                 putchar(isprint(s[i]) ? s[i] : '.');
 443         if (btrfs_super_magic(sb) == BTRFS_MAGIC)
 444                 printf(" [match]\n");
 445         else
 446                 printf(" [DON'T MATCH]\n");
 447
 448         uuid_unparse(sb->fsid, buf);
 449         printf("fsid\t\t\t%s\n", buf);
 450
 451         printf("label\t\t\t");
 452         s = sb->label;
 453         for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
 454                 putchar(isprint(s[i]) ? s[i] : '.');
 455         putchar('\n');
 456
 457         printf("generation\t\t%llu\n",
 458                (unsigned long long)btrfs_super_generation(sb));
 459         printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
 460         printf("sys_array_size\t\t%llu\n",
 461                (unsigned long long)btrfs_super_sys_array_size(sb));
 462         printf("chunk_root_generation\t%llu\n",
 463                (unsigned long long)btrfs_super_chunk_root_generation(sb));
 464         printf("root_level\t\t%llu\n",
 465                (unsigned long long)btrfs_super_root_level(sb));
 466         printf("chunk_root\t\t%llu\n",
 467                (unsigned long long)btrfs_super_chunk_root(sb));
 468         printf("chunk_root_level\t%llu\n",
 469                (unsigned long long)btrfs_super_chunk_root_level(sb));
 470         printf("log_root\t\t%llu\n",
 471                (unsigned long long)btrfs_super_log_root(sb));
 472         printf("log_root_transid\t%llu\n",
 473                (unsigned long long)btrfs_super_log_root_transid(sb));
 474         printf("log_root_level\t\t%llu\n",
 475                (unsigned long long)btrfs_super_log_root_level(sb));
 476         printf("total_bytes\t\t%llu\n",
 477                (unsigned long long)btrfs_super_total_bytes(sb));
 478         printf("bytes_used\t\t%llu\n",
 479                (unsigned long long)btrfs_super_bytes_used(sb));
 480         printf("sectorsize\t\t%llu\n",
 481                (unsigned long long)btrfs_super_sectorsize(sb));
 482         printf("nodesize\t\t%llu\n",
 483                (unsigned long long)btrfs_super_nodesize(sb));
 484         printf("leafsize\t\t%llu\n",
 485                (unsigned long long)btrfs_super_leafsize(sb));
 486         printf("stripesize\t\t%llu\n",
 487                (unsigned long long)btrfs_super_stripesize(sb));
 488         printf("root_dir\t\t%llu\n",
 489                (unsigned long long)btrfs_super_root_dir(sb));
 490         printf("num_devices\t\t%llu\n",
 491                (unsigned long long)btrfs_super_num_devices(sb));
 492         printf("compat_flags\t\t0x%llx\n",
 493                (unsigned long long)btrfs_super_compat_flags(sb));
 494         printf("compat_ro_flags\t\t0x%llx\n",
 495                (unsigned long long)btrfs_super_compat_ro_flags(sb));
 496         printf("incompat_flags\t\t0x%llx\n",
 497                (unsigned long long)btrfs_super_incompat_flags(sb));
 498         print_readable_incompat_flag(btrfs_super_incompat_flags(sb));
 499         printf("csum_type\t\t%llu\n",
 500                (unsigned long long)btrfs_super_csum_type(sb));
 501         printf("csum_size\t\t%llu\n",
 502                (unsigned long long)btrfs_super_csum_size(sb));
 503         printf("cache_generation\t%llu\n",
 504                (unsigned long long)btrfs_super_cache_generation(sb));
 505         printf("uuid_tree_generation\t%llu\n",
 506                (unsigned long long)btrfs_super_uuid_tree_generation(sb));
 507
 508         uuid_unparse(sb->dev_item.uuid, buf);
 509         printf("dev_item.uuid\t\t%s\n", buf);
 510
 511         uuid_unparse(sb->dev_item.fsid, buf);
 512         printf("dev_item.fsid\t\t%s %s\n", buf,
 513                 !memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
 514                         "[match]" : "[DON'T MATCH]");
 515
 516         printf("dev_item.type\t\t%llu\n", (unsigned long long)
 517                btrfs_stack_device_type(&sb->dev_item));
 518         printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
 519                btrfs_stack_device_total_bytes(&sb->dev_item));
 520         printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
 521                btrfs_stack_device_bytes_used(&sb->dev_item));
 522         printf("dev_item.io_align\t%u\n", (unsigned int)
 523                btrfs_stack_device_io_align(&sb->dev_item));
 524         printf("dev_item.io_width\t%u\n", (unsigned int)
 525                btrfs_stack_device_io_width(&sb->dev_item));
 526         printf("dev_item.sector_size\t%u\n", (unsigned int)
 527                btrfs_stack_device_sector_size(&sb->dev_item));
 528         printf("dev_item.devid\t\t%llu\n",
 529                btrfs_stack_device_id(&sb->dev_item));
 530         printf("dev_item.dev_group\t%u\n", (unsigned int)
 531                btrfs_stack_device_group(&sb->dev_item));
 532         printf("dev_item.seek_speed\t%u\n", (unsigned int)
 533                btrfs_stack_device_seek_speed(&sb->dev_item));
 534         printf("dev_item.bandwidth\t%u\n", (unsigned int)
 535                btrfs_stack_device_bandwidth(&sb->dev_item));
 536         printf("dev_item.generation\t%llu\n", (unsigned long long)
 537                btrfs_stack_device_generation(&sb->dev_item));
 538         if (full) {
 539                 printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
 540                 print_sys_chunk_array(sb);
 541                 printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
 542                 print_backup_roots(sb);
 543         }
 544 }