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, "%s\n", PACKAGE_STRING);
  52 }
  53
  54 int main(int argc, char **argv)
  55 {
  56         int opt;
  57         int all = 0;
  58         int full = 0;
  59         int force = 0;
  60         char *filename;
  61         int fd = -1;
  62         int i;
  63         u64 arg;
  64         u64 sb_bytenr = btrfs_sb_offset(0);
  65
  66         while ((opt = getopt(argc, argv, "fFai:")) != -1) {
  67                 switch (opt) {
  68                 case 'i':
  69                         arg = arg_strtou64(optarg);
  70                         if (arg >= BTRFS_SUPER_MIRROR_MAX) {
  71                                 fprintf(stderr,
  72                                         "Illegal super_mirror %llu\n",
  73                                         arg);
  74                                 print_usage();
  75                                 exit(1);
  76                         }
  77                         sb_bytenr = btrfs_sb_offset(arg);
  78                         break;
  79
  80                 case 'a':
  81                         all = 1;
  82                         break;
  83                 case 'f':
  84                         full = 1;
  85                         break;
  86                 case 'F':
  87                         force = 1;
  88                         break;
  89                 default:
  90                         print_usage();
  91                         exit(1);
  92                 }
  93         }
  94
  95         set_argv0(argv);
  96         if (check_argc_min(argc - optind, 1)) {
  97                 print_usage();
  98                 exit(1);
  99         }
 100
 101         for (i = optind; i < argc; i++) {
 102                 filename = argv[i];
 103                 fd = open(filename, O_RDONLY, 0666);
 104                 if (fd < 0) {
 105                         fprintf(stderr, "Could not open %s\n", filename);
 106                         exit(1);
 107                 }
 108
 109                 if (all) {
 110                         int idx;
 111                         for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
 112                                 sb_bytenr = btrfs_sb_offset(idx);
 113                                 if (load_and_dump_sb(filename, fd,
 114                                                 sb_bytenr, full, force)) {
 115                                         close(fd);
 116                                         exit(1);
 117                                 }
 118
 119                                 putchar('\n');
 120                         }
 121                 } else {
 122                         load_and_dump_sb(filename, fd, sb_bytenr, full, force);
 123                         putchar('\n');
 124                 }
 125                 close(fd);
 126         }
 127
 128         exit(0);
 129 }
 130
 131 static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full,
 132                 int force)
 133 {
 134         u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
 135         struct btrfs_super_block *sb;
 136         u64 ret;
 137
 138         sb = (struct btrfs_super_block *)super_block_data;
 139
 140         ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
 141         if (ret != BTRFS_SUPER_INFO_SIZE) {
 142                 int e = errno;
 143
 144                 /* check if the disk if too short for further superblock */
 145                 if (ret == 0 && e == 0)
 146                         return 0;
 147
 148                 fprintf(stderr,
 149                    "ERROR: Failed to read the superblock on %s at %llu\n",
 150                    filename, (unsigned long long)sb_bytenr);
 151                 fprintf(stderr,
 152                    "ERROR: error = '%s', errno = %d\n", strerror(e), e);
 153                 return 1;
 154         }
 155         printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
 156         printf("---------------------------------------------------------\n");
 157         if (btrfs_super_magic(sb) != BTRFS_MAGIC && !force) {
 158                 fprintf(stderr,
 159                     "ERROR: bad magic on superblock on %s at %llu\n",
 160                     filename, (unsigned long long)sb_bytenr);
 161         } else {
 162                 dump_superblock(sb, full);
 163         }
 164         return 0;
 165 }
 166
 167 static int check_csum_sblock(void *sb, int csum_size)
 168 {
 169         char result[BTRFS_CSUM_SIZE];
 170         u32 crc = ~(u32)0;
 171
 172         crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
 173                                 crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 174         btrfs_csum_final(crc, result);
 175
 176         return !memcmp(sb, &result, csum_size);
 177 }
 178
 179 static void print_sys_chunk_array(struct btrfs_super_block *sb)
 180 {
 181         struct extent_buffer *buf;
 182         struct btrfs_disk_key *disk_key;
 183         struct btrfs_chunk *chunk;
 184         struct btrfs_key key;
 185         u8 *ptr, *array_end;
 186         u32 num_stripes;
 187         u32 len = 0;
 188         int i = 0;
 189
 190         buf = malloc(sizeof(*buf) + sizeof(*sb));
 191         if (!buf) {
 192                 fprintf(stderr, "%s\n", strerror(ENOMEM));
 193                 exit(1);
 194         }
 195         write_extent_buffer(buf, sb, 0, sizeof(*sb));
 196         ptr = sb->sys_chunk_array;
 197         array_end = ptr + btrfs_super_sys_array_size(sb);
 198
 199         while (ptr < array_end) {
 200                 disk_key = (struct btrfs_disk_key *)ptr;
 201                 btrfs_disk_key_to_cpu(&key, disk_key);
 202
 203                 printf("\titem %d ", i);
 204                 btrfs_print_key(disk_key);
 205
 206                 len = sizeof(*disk_key);
 207                 putchar('\n');
 208                 ptr += len;
 209
 210                 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
 211                         chunk = (struct btrfs_chunk *)(ptr - (u8 *)sb);
 212                         print_chunk(buf, chunk);
 213                         num_stripes = btrfs_chunk_num_stripes(buf, chunk);
 214                         len = btrfs_chunk_item_size(num_stripes);
 215                 } else {
 216                         BUG();
 217                 }
 218
 219                 ptr += len;
 220                 i++;
 221         }
 222
 223         free(buf);
 224 }
 225
 226 static int empty_backup(struct btrfs_root_backup *backup)
 227 {
 228         if (backup == NULL ||
 229                 (backup->tree_root == 0 &&
 230                  backup->tree_root_gen == 0))
 231                 return 1;
 232         return 0;
 233 }
 234
 235 static void print_root_backup(struct btrfs_root_backup *backup)
 236 {
 237         printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
 238                         btrfs_backup_tree_root(backup),
 239                         btrfs_backup_tree_root_gen(backup),
 240                         btrfs_backup_tree_root_level(backup));
 241         printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
 242                         btrfs_backup_chunk_root(backup),
 243                         btrfs_backup_chunk_root_gen(backup),
 244                         btrfs_backup_chunk_root_level(backup));
 245         printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
 246                         btrfs_backup_extent_root(backup),
 247                         btrfs_backup_extent_root_gen(backup),
 248                         btrfs_backup_extent_root_level(backup));
 249         printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
 250                         btrfs_backup_fs_root(backup),
 251                         btrfs_backup_fs_root_gen(backup),
 252                         btrfs_backup_fs_root_level(backup));
 253         printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
 254                         btrfs_backup_dev_root(backup),
 255                         btrfs_backup_dev_root_gen(backup),
 256                         btrfs_backup_dev_root_level(backup));
 257         printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
 258                         btrfs_backup_csum_root(backup),
 259                         btrfs_backup_csum_root_gen(backup),
 260                         btrfs_backup_csum_root_level(backup));
 261
 262         printf("\t\tbackup_total_bytes:\t%llu\n",
 263                                         btrfs_backup_total_bytes(backup));
 264         printf("\t\tbackup_bytes_used:\t%llu\n",
 265                                         btrfs_backup_bytes_used(backup));
 266         printf("\t\tbackup_num_devices:\t%llu\n",
 267                                         btrfs_backup_num_devices(backup));
 268         putchar('\n');
 269 }
 270
 271 static void print_backup_roots(struct btrfs_super_block *sb)
 272 {
 273         struct btrfs_root_backup *backup;
 274         int i;
 275
 276         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
 277                 backup = sb->super_roots + i;
 278                 if (!empty_backup(backup)) {
 279                         printf("\tbackup %d:\n", i);
 280                         print_root_backup(backup);
 281                 }
 282         }
 283 }
 284
 285 struct readable_flag_entry {
 286         u64 bit;
 287         char *output;
 288 };
 289
 290 #define DEF_INCOMPAT_FLAG_ENTRY(bit_name)               \
 291         {BTRFS_FEATURE_INCOMPAT_##bit_name, #bit_name}
 292
 293 struct readable_flag_entry incompat_flags_array[] = {
 294         DEF_INCOMPAT_FLAG_ENTRY(MIXED_BACKREF),
 295         DEF_INCOMPAT_FLAG_ENTRY(DEFAULT_SUBVOL),
 296         DEF_INCOMPAT_FLAG_ENTRY(MIXED_GROUPS),
 297         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZO),
 298         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZOv2),
 299         DEF_INCOMPAT_FLAG_ENTRY(BIG_METADATA),
 300         DEF_INCOMPAT_FLAG_ENTRY(EXTENDED_IREF),
 301         DEF_INCOMPAT_FLAG_ENTRY(RAID56),
 302         DEF_INCOMPAT_FLAG_ENTRY(SKINNY_METADATA),
 303         DEF_INCOMPAT_FLAG_ENTRY(NO_HOLES)
 304 };
 305 static const int incompat_flags_num = sizeof(incompat_flags_array) /
 306                                       sizeof(struct readable_flag_entry);
 307
 308 static void print_readable_incompat_flag(u64 flag)
 309 {
 310         int i;
 311         int first = 1;
 312         struct readable_flag_entry *entry;
 313
 314         if (!flag)
 315                 return;
 316         printf("\t\t\t( ");
 317         for (i = 0; i < incompat_flags_num; i++) {
 318                 entry = incompat_flags_array + i;
 319                 if (flag & entry->bit) {
 320                         if (first)
 321                                 printf("%s ", entry->output);
 322                         else
 323                                 printf("|\n\t\t\t  %s ", entry->output);
 324                         first = 0;
 325                 }
 326         }
 327         flag &= ~BTRFS_FEATURE_INCOMPAT_SUPP;
 328         if (flag) {
 329                 if (first)
 330                         printf("unknown flag: 0x%llx ", flag);
 331                 else
 332                         printf("|\n\t\t\t  unknown flag: 0x%llx ", flag);
 333         }
 334         printf(")\n");
 335 }
 336
 337 static void dump_superblock(struct btrfs_super_block *sb, int full)
 338 {
 339         int i;
 340         char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
 341         u8 *p;
 342
 343         printf("csum\t\t\t0x");
 344         for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)
 345                 printf("%02x", p[i]);
 346         if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
 347                 printf(" [match]");
 348         else
 349                 printf(" [DON'T MATCH]");
 350         putchar('\n');
 351
 352         printf("bytenr\t\t\t%llu\n",
 353                 (unsigned long long)btrfs_super_bytenr(sb));
 354         printf("flags\t\t\t0x%llx\n",
 355                 (unsigned long long)btrfs_super_flags(sb));
 356
 357         printf("magic\t\t\t");
 358         s = (char *) &sb->magic;
 359         for (i = 0; i < 8; i++)
 360                 putchar(isprint(s[i]) ? s[i] : '.');
 361         if (btrfs_super_magic(sb) == BTRFS_MAGIC)
 362                 printf(" [match]\n");
 363         else
 364                 printf(" [DON'T MATCH]\n");
 365
 366         uuid_unparse(sb->fsid, buf);
 367         printf("fsid\t\t\t%s\n", buf);
 368
 369         printf("label\t\t\t");
 370         s = sb->label;
 371         for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
 372                 putchar(isprint(s[i]) ? s[i] : '.');
 373         putchar('\n');
 374
 375         printf("generation\t\t%llu\n",
 376                (unsigned long long)btrfs_super_generation(sb));
 377         printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
 378         printf("sys_array_size\t\t%llu\n",
 379                (unsigned long long)btrfs_super_sys_array_size(sb));
 380         printf("chunk_root_generation\t%llu\n",
 381                (unsigned long long)btrfs_super_chunk_root_generation(sb));
 382         printf("root_level\t\t%llu\n",
 383                (unsigned long long)btrfs_super_root_level(sb));
 384         printf("chunk_root\t\t%llu\n",
 385                (unsigned long long)btrfs_super_chunk_root(sb));
 386         printf("chunk_root_level\t%llu\n",
 387                (unsigned long long)btrfs_super_chunk_root_level(sb));
 388         printf("log_root\t\t%llu\n",
 389                (unsigned long long)btrfs_super_log_root(sb));
 390         printf("log_root_transid\t%llu\n",
 391                (unsigned long long)btrfs_super_log_root_transid(sb));
 392         printf("log_root_level\t\t%llu\n",
 393                (unsigned long long)btrfs_super_log_root_level(sb));
 394         printf("total_bytes\t\t%llu\n",
 395                (unsigned long long)btrfs_super_total_bytes(sb));
 396         printf("bytes_used\t\t%llu\n",
 397                (unsigned long long)btrfs_super_bytes_used(sb));
 398         printf("sectorsize\t\t%llu\n",
 399                (unsigned long long)btrfs_super_sectorsize(sb));
 400         printf("nodesize\t\t%llu\n",
 401                (unsigned long long)btrfs_super_nodesize(sb));
 402         printf("leafsize\t\t%llu\n",
 403                (unsigned long long)btrfs_super_leafsize(sb));
 404         printf("stripesize\t\t%llu\n",
 405                (unsigned long long)btrfs_super_stripesize(sb));
 406         printf("root_dir\t\t%llu\n",
 407                (unsigned long long)btrfs_super_root_dir(sb));
 408         printf("num_devices\t\t%llu\n",
 409                (unsigned long long)btrfs_super_num_devices(sb));
 410         printf("compat_flags\t\t0x%llx\n",
 411                (unsigned long long)btrfs_super_compat_flags(sb));
 412         printf("compat_ro_flags\t\t0x%llx\n",
 413                (unsigned long long)btrfs_super_compat_ro_flags(sb));
 414         printf("incompat_flags\t\t0x%llx\n",
 415                (unsigned long long)btrfs_super_incompat_flags(sb));
 416         print_readable_incompat_flag(btrfs_super_incompat_flags(sb));
 417         printf("csum_type\t\t%llu\n",
 418                (unsigned long long)btrfs_super_csum_type(sb));
 419         printf("csum_size\t\t%llu\n",
 420                (unsigned long long)btrfs_super_csum_size(sb));
 421         printf("cache_generation\t%llu\n",
 422                (unsigned long long)btrfs_super_cache_generation(sb));
 423         printf("uuid_tree_generation\t%llu\n",
 424                (unsigned long long)btrfs_super_uuid_tree_generation(sb));
 425
 426         uuid_unparse(sb->dev_item.uuid, buf);
 427         printf("dev_item.uuid\t\t%s\n", buf);
 428
 429         uuid_unparse(sb->dev_item.fsid, buf);
 430         printf("dev_item.fsid\t\t%s %s\n", buf,
 431                 !memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
 432                         "[match]" : "[DON'T MATCH]");
 433
 434         printf("dev_item.type\t\t%llu\n", (unsigned long long)
 435                btrfs_stack_device_type(&sb->dev_item));
 436         printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
 437                btrfs_stack_device_total_bytes(&sb->dev_item));
 438         printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
 439                btrfs_stack_device_bytes_used(&sb->dev_item));
 440         printf("dev_item.io_align\t%u\n", (unsigned int)
 441                btrfs_stack_device_io_align(&sb->dev_item));
 442         printf("dev_item.io_width\t%u\n", (unsigned int)
 443                btrfs_stack_device_io_width(&sb->dev_item));
 444         printf("dev_item.sector_size\t%u\n", (unsigned int)
 445                btrfs_stack_device_sector_size(&sb->dev_item));
 446         printf("dev_item.devid\t\t%llu\n",
 447                btrfs_stack_device_id(&sb->dev_item));
 448         printf("dev_item.dev_group\t%u\n", (unsigned int)
 449                btrfs_stack_device_group(&sb->dev_item));
 450         printf("dev_item.seek_speed\t%u\n", (unsigned int)
 451                btrfs_stack_device_seek_speed(&sb->dev_item));
 452         printf("dev_item.bandwidth\t%u\n", (unsigned int)
 453                btrfs_stack_device_bandwidth(&sb->dev_item));
 454         printf("dev_item.generation\t%llu\n", (unsigned long long)
 455                btrfs_stack_device_generation(&sb->dev_item));
 456         if (full) {
 457                 printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
 458                 print_sys_chunk_array(sb);
 459                 printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
 460                 print_backup_roots(sb);
 461         }
 462 }