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