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 #define _XOPEN_SOURCE 500
  20 #define _GNU_SOURCE 1
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25 #include <sys/stat.h>
  26 #include <ctype.h>
  27 #include <uuid/uuid.h>
  28 #include <errno.h>
  29
  30 #include "kerncompat.h"
  31 #include "ctree.h"
  32 #include "disk-io.h"
  33 #include "print-tree.h"
  34 #include "transaction.h"
  35 #include "list.h"
  36 #include "version.h"
  37 #include "utils.h"
  38 #include "crc32c.h"
  39
  40 static void print_usage(void);
  41 static void dump_superblock(struct btrfs_super_block *sb, int full);
  42 int main(int argc, char **argv);
  43 static int load_and_dump_sb(char *, int fd, u64 sb_bytenr, int full, int force);
  44
  45
  46 static void print_usage(void)
  47 {
  48         fprintf(stderr,
  49                 "usage: btrfs-show-super [-i super_mirror|-a|-f|-F] dev [dev..]\n");
  50         fprintf(stderr, "\t-f : print full superblock information\n");
  51         fprintf(stderr, "\t-a : print information of all superblocks\n");
  52         fprintf(stderr, "\t-i <super_mirror> : specify which mirror to print out\n");
  53         fprintf(stderr, "\t-F : attempt to dump superblocks with bad magic\n");
  54         fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
  55 }
  56
  57 int main(int argc, char **argv)
  58 {
  59         int opt;
  60         int all = 0;
  61         int full = 0;
  62         int force = 0;
  63         char *filename;
  64         int fd = -1;
  65         int i;
  66         u64 arg;
  67         u64 sb_bytenr = btrfs_sb_offset(0);
  68
  69         while ((opt = getopt(argc, argv, "fFai:")) != -1) {
  70                 switch (opt) {
  71                 case 'i':
  72                         arg = arg_strtou64(optarg);
  73                         if (arg >= BTRFS_SUPER_MIRROR_MAX) {
  74                                 fprintf(stderr,
  75                                         "Illegal super_mirror %llu\n",
  76                                         arg);
  77                                 print_usage();
  78                                 exit(1);
  79                         }
  80                         sb_bytenr = btrfs_sb_offset(arg);
  81                         break;
  82
  83                 case 'a':
  84                         all = 1;
  85                         break;
  86                 case 'f':
  87                         full = 1;
  88                         break;
  89                 case 'F':
  90                         force = 1;
  91                         break;
  92                 default:
  93                         print_usage();
  94                         exit(1);
  95                 }
  96         }
  97
  98         set_argv0(argv);
  99         if (check_argc_min(argc - optind, 1)) {
 100                 print_usage();
 101                 exit(1);
 102         }
 103
 104         for (i = optind; i < argc; i++) {
 105                 filename = argv[i];
 106                 fd = open(filename, O_RDONLY, 0666);
 107                 if (fd < 0) {
 108                         fprintf(stderr, "Could not open %s\n", filename);
 109                         exit(1);
 110                 }
 111
 112                 if (all) {
 113                         int idx;
 114                         for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
 115                                 sb_bytenr = btrfs_sb_offset(idx);
 116                                 if (load_and_dump_sb(filename, fd,
 117                                                 sb_bytenr, full, force)) {
 118                                         close(fd);
 119                                         exit(1);
 120                                 }
 121
 122                                 putchar('\n');
 123                         }
 124                 } else {
 125                         load_and_dump_sb(filename, fd, sb_bytenr, full, force);
 126                         putchar('\n');
 127                 }
 128                 close(fd);
 129         }
 130
 131         exit(0);
 132 }
 133
 134 static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full,
 135                 int force)
 136 {
 137         u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
 138         struct btrfs_super_block *sb;
 139         u64 ret;
 140
 141         sb = (struct btrfs_super_block *)super_block_data;
 142
 143         ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
 144         if (ret != BTRFS_SUPER_INFO_SIZE) {
 145                 int e = errno;
 146
 147                 /* check if the disk if too short for further superblock */
 148                 if (ret == 0 && e == 0)
 149                         return 0;
 150
 151                 fprintf(stderr,
 152                    "ERROR: Failed to read the superblock on %s at %llu\n",
 153                    filename, (unsigned long long)sb_bytenr);
 154                 fprintf(stderr,
 155                    "ERROR: error = '%s', errno = %d\n", strerror(e), e);
 156                 return 1;
 157         }
 158         printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
 159         printf("---------------------------------------------------------\n");
 160         if (btrfs_super_magic(sb) != BTRFS_MAGIC && !force) {
 161                 fprintf(stderr,
 162                     "ERROR: bad magic on superblock on %s at %llu\n",
 163                     filename, (unsigned long long)sb_bytenr);
 164         } else {
 165                 dump_superblock(sb, full);
 166         }
 167         return 0;
 168 }
 169
 170 static int check_csum_sblock(void *sb, int csum_size)
 171 {
 172         char result[BTRFS_CSUM_SIZE];
 173         u32 crc = ~(u32)0;
 174
 175         crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
 176                                 crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 177         btrfs_csum_final(crc, result);
 178
 179         return !memcmp(sb, &result, csum_size);
 180 }
 181
 182 static void print_sys_chunk_array(struct btrfs_super_block *sb)
 183 {
 184         struct extent_buffer *buf;
 185         struct btrfs_disk_key *disk_key;
 186         struct btrfs_chunk *chunk;
 187         struct btrfs_key key;
 188         u8 *ptr, *array_end;
 189         u32 num_stripes;
 190         u32 len = 0;
 191         int i = 0;
 192
 193         buf = malloc(sizeof(*buf) + sizeof(*sb));
 194         if (!buf) {
 195                 fprintf(stderr, "%s\n", strerror(ENOMEM));
 196                 exit(1);
 197         }
 198         write_extent_buffer(buf, sb, 0, sizeof(*sb));
 199         ptr = sb->sys_chunk_array;
 200         array_end = ptr + btrfs_super_sys_array_size(sb);
 201
 202         while (ptr < array_end) {
 203                 disk_key = (struct btrfs_disk_key *)ptr;
 204                 btrfs_disk_key_to_cpu(&key, disk_key);
 205
 206                 printf("\titem %d ", i);
 207                 btrfs_print_key(disk_key);
 208
 209                 len = sizeof(*disk_key);
 210                 putchar('\n');
 211                 ptr += len;
 212
 213                 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
 214                         chunk = (struct btrfs_chunk *)(ptr - (u8 *)sb);
 215                         print_chunk(buf, chunk);
 216                         num_stripes = btrfs_chunk_num_stripes(buf, chunk);
 217                         len = btrfs_chunk_item_size(num_stripes);
 218                 } else {
 219                         BUG();
 220                 }
 221
 222                 ptr += len;
 223                 i++;
 224         }
 225
 226         free(buf);
 227 }
 228
 229 static int empty_backup(struct btrfs_root_backup *backup)
 230 {
 231         if (backup == NULL ||
 232                 (backup->tree_root == 0 &&
 233                  backup->tree_root_gen == 0))
 234                 return 1;
 235         return 0;
 236 }
 237
 238 static void print_root_backup(struct btrfs_root_backup *backup)
 239 {
 240         printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
 241                         btrfs_backup_tree_root(backup),
 242                         btrfs_backup_tree_root_gen(backup),
 243                         btrfs_backup_tree_root_level(backup));
 244         printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
 245                         btrfs_backup_chunk_root(backup),
 246                         btrfs_backup_chunk_root_gen(backup),
 247                         btrfs_backup_chunk_root_level(backup));
 248         printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
 249                         btrfs_backup_extent_root(backup),
 250                         btrfs_backup_extent_root_gen(backup),
 251                         btrfs_backup_extent_root_level(backup));
 252         printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
 253                         btrfs_backup_fs_root(backup),
 254                         btrfs_backup_fs_root_gen(backup),
 255                         btrfs_backup_fs_root_level(backup));
 256         printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
 257                         btrfs_backup_dev_root(backup),
 258                         btrfs_backup_dev_root_gen(backup),
 259                         btrfs_backup_dev_root_level(backup));
 260         printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
 261                         btrfs_backup_csum_root(backup),
 262                         btrfs_backup_csum_root_gen(backup),
 263                         btrfs_backup_csum_root_level(backup));
 264
 265         printf("\t\tbackup_total_bytes:\t%llu\n",
 266                                         btrfs_backup_total_bytes(backup));
 267         printf("\t\tbackup_bytes_used:\t%llu\n",
 268                                         btrfs_backup_bytes_used(backup));
 269         printf("\t\tbackup_num_devices:\t%llu\n",
 270                                         btrfs_backup_num_devices(backup));
 271         putchar('\n');
 272 }
 273
 274 static void print_backup_roots(struct btrfs_super_block *sb)
 275 {
 276         struct btrfs_root_backup *backup;
 277         int i;
 278
 279         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
 280                 backup = sb->super_roots + i;
 281                 if (!empty_backup(backup)) {
 282                         printf("\tbackup %d:\n", i);
 283                         print_root_backup(backup);
 284                 }
 285         }
 286 }
 287
 288 struct readable_flag_entry {
 289         u64 bit;
 290         char *output;
 291 };
 292
 293 #define DEF_INCOMPAT_FLAG_ENTRY(bit_name)               \
 294         {BTRFS_FEATURE_INCOMPAT_##bit_name, #bit_name}
 295
 296 struct readable_flag_entry incompat_flags_array[] = {
 297         DEF_INCOMPAT_FLAG_ENTRY(MIXED_BACKREF),
 298         DEF_INCOMPAT_FLAG_ENTRY(DEFAULT_SUBVOL),
 299         DEF_INCOMPAT_FLAG_ENTRY(MIXED_GROUPS),
 300         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZO),
 301         DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZOv2),
 302         DEF_INCOMPAT_FLAG_ENTRY(BIG_METADATA),
 303         DEF_INCOMPAT_FLAG_ENTRY(EXTENDED_IREF),
 304         DEF_INCOMPAT_FLAG_ENTRY(RAID56),
 305         DEF_INCOMPAT_FLAG_ENTRY(SKINNY_METADATA),
 306         DEF_INCOMPAT_FLAG_ENTRY(NO_HOLES)
 307 };
 308 static const int incompat_flags_num = sizeof(incompat_flags_array) /
 309                                       sizeof(struct readable_flag_entry);
 310
 311 static void print_readable_incompat_flag(u64 flag)
 312 {
 313         int i;
 314         int first = 1;
 315         struct readable_flag_entry *entry;
 316
 317         if (!flag)
 318                 return;
 319         printf("\t\t\t( ");
 320         for (i = 0; i < incompat_flags_num; i++) {
 321                 entry = incompat_flags_array + i;
 322                 if (flag & entry->bit) {
 323                         if (first)
 324                                 printf("%s ", entry->output);
 325                         else
 326                                 printf("|\n\t\t\t  %s ", entry->output);
 327                         first = 0;
 328                 }
 329         }
 330         flag &= ~BTRFS_FEATURE_INCOMPAT_SUPP;
 331         if (flag) {
 332                 if (first)
 333                         printf("unknown flag: 0x%llx ", flag);
 334                 else
 335                         printf("|\n\t\t\t  unknown flag: 0x%llx ", flag);
 336         }
 337         printf(")\n");
 338 }
 339
 340 static void dump_superblock(struct btrfs_super_block *sb, int full)
 341 {
 342         int i;
 343         char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
 344         u8 *p;
 345
 346         printf("csum\t\t\t0x");
 347         for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)
 348                 printf("%02x", p[i]);
 349         if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
 350                 printf(" [match]");
 351         else
 352                 printf(" [DON'T MATCH]");
 353         putchar('\n');
 354
 355         printf("bytenr\t\t\t%llu\n",
 356                 (unsigned long long)btrfs_super_bytenr(sb));
 357         printf("flags\t\t\t0x%llx\n",
 358                 (unsigned long long)btrfs_super_flags(sb));
 359
 360         printf("magic\t\t\t");
 361         s = (char *) &sb->magic;
 362         for (i = 0; i < 8; i++)
 363                 putchar(isprint(s[i]) ? s[i] : '.');
 364         if (btrfs_super_magic(sb) == BTRFS_MAGIC)
 365                 printf(" [match]\n");
 366         else
 367                 printf(" [DON'T MATCH]\n");
 368
 369         uuid_unparse(sb->fsid, buf);
 370         printf("fsid\t\t\t%s\n", buf);
 371
 372         printf("label\t\t\t");
 373         s = sb->label;
 374         for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
 375                 putchar(isprint(s[i]) ? s[i] : '.');
 376         putchar('\n');
 377
 378         printf("generation\t\t%llu\n",
 379                (unsigned long long)btrfs_super_generation(sb));
 380         printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
 381         printf("sys_array_size\t\t%llu\n",
 382                (unsigned long long)btrfs_super_sys_array_size(sb));
 383         printf("chunk_root_generation\t%llu\n",
 384                (unsigned long long)btrfs_super_chunk_root_generation(sb));
 385         printf("root_level\t\t%llu\n",
 386                (unsigned long long)btrfs_super_root_level(sb));
 387         printf("chunk_root\t\t%llu\n",
 388                (unsigned long long)btrfs_super_chunk_root(sb));
 389         printf("chunk_root_level\t%llu\n",
 390                (unsigned long long)btrfs_super_chunk_root_level(sb));
 391         printf("log_root\t\t%llu\n",
 392                (unsigned long long)btrfs_super_log_root(sb));
 393         printf("log_root_transid\t%llu\n",
 394                (unsigned long long)btrfs_super_log_root_transid(sb));
 395         printf("log_root_level\t\t%llu\n",
 396                (unsigned long long)btrfs_super_log_root_level(sb));
 397         printf("total_bytes\t\t%llu\n",
 398                (unsigned long long)btrfs_super_total_bytes(sb));
 399         printf("bytes_used\t\t%llu\n",
 400                (unsigned long long)btrfs_super_bytes_used(sb));
 401         printf("sectorsize\t\t%llu\n",
 402                (unsigned long long)btrfs_super_sectorsize(sb));
 403         printf("nodesize\t\t%llu\n",
 404                (unsigned long long)btrfs_super_nodesize(sb));
 405         printf("leafsize\t\t%llu\n",
 406                (unsigned long long)btrfs_super_leafsize(sb));
 407         printf("stripesize\t\t%llu\n",
 408                (unsigned long long)btrfs_super_stripesize(sb));
 409         printf("root_dir\t\t%llu\n",
 410                (unsigned long long)btrfs_super_root_dir(sb));
 411         printf("num_devices\t\t%llu\n",
 412                (unsigned long long)btrfs_super_num_devices(sb));
 413         printf("compat_flags\t\t0x%llx\n",
 414                (unsigned long long)btrfs_super_compat_flags(sb));
 415         printf("compat_ro_flags\t\t0x%llx\n",
 416                (unsigned long long)btrfs_super_compat_ro_flags(sb));
 417         printf("incompat_flags\t\t0x%llx\n",
 418                (unsigned long long)btrfs_super_incompat_flags(sb));
 419         print_readable_incompat_flag(btrfs_super_incompat_flags(sb));
 420         printf("csum_type\t\t%llu\n",
 421                (unsigned long long)btrfs_super_csum_type(sb));
 422         printf("csum_size\t\t%llu\n",
 423                (unsigned long long)btrfs_super_csum_size(sb));
 424         printf("cache_generation\t%llu\n",
 425                (unsigned long long)btrfs_super_cache_generation(sb));
 426         printf("uuid_tree_generation\t%llu\n",
 427                (unsigned long long)btrfs_super_uuid_tree_generation(sb));
 428
 429         uuid_unparse(sb->dev_item.uuid, buf);
 430         printf("dev_item.uuid\t\t%s\n", buf);
 431
 432         uuid_unparse(sb->dev_item.fsid, buf);
 433         printf("dev_item.fsid\t\t%s %s\n", buf,
 434                 !memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
 435                         "[match]" : "[DON'T MATCH]");
 436
 437         printf("dev_item.type\t\t%llu\n", (unsigned long long)
 438                btrfs_stack_device_type(&sb->dev_item));
 439         printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
 440                btrfs_stack_device_total_bytes(&sb->dev_item));
 441         printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
 442                btrfs_stack_device_bytes_used(&sb->dev_item));
 443         printf("dev_item.io_align\t%u\n", (unsigned int)
 444                btrfs_stack_device_io_align(&sb->dev_item));
 445         printf("dev_item.io_width\t%u\n", (unsigned int)
 446                btrfs_stack_device_io_width(&sb->dev_item));
 447         printf("dev_item.sector_size\t%u\n", (unsigned int)
 448                btrfs_stack_device_sector_size(&sb->dev_item));
 449         printf("dev_item.devid\t\t%llu\n",
 450                btrfs_stack_device_id(&sb->dev_item));
 451         printf("dev_item.dev_group\t%u\n", (unsigned int)
 452                btrfs_stack_device_group(&sb->dev_item));
 453         printf("dev_item.seek_speed\t%u\n", (unsigned int)
 454                btrfs_stack_device_seek_speed(&sb->dev_item));
 455         printf("dev_item.bandwidth\t%u\n", (unsigned int)
 456                btrfs_stack_device_bandwidth(&sb->dev_item));
 457         printf("dev_item.generation\t%llu\n", (unsigned long long)
 458                btrfs_stack_device_generation(&sb->dev_item));
 459         if (full) {
 460                 printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
 461                 print_sys_chunk_array(sb);
 462                 printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
 463                 print_backup_roots(sb);
 464         }
 465 }