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);
  44
  45
  46 static void print_usage(void)
  47 {
  48         fprintf(stderr,
  49                 "usage: btrfs-show-super [-i super_mirror|-a|-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, "%s\n", BTRFS_BUILD_VERSION);
  54 }
  55
  56 int main(int argc, char **argv)
  57 {
  58         int opt;
  59         int all = 0;
  60         int full = 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, "fai:")) != -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                 default:
  88                         print_usage();
  89                         exit(1);
  90                 }
  91         }
  92
  93         if (argc < optind + 1) {
  94                 print_usage();
  95                 exit(1);
  96         }
  97
  98         for (i = optind; i < argc; i++) {
  99                 filename = argv[i];
 100                 fd = open(filename, O_RDONLY, 0666);
 101                 if (fd < 0) {
 102                         fprintf(stderr, "Could not open %s\n", filename);
 103                         exit(1);
 104                 }
 105
 106                 if (all) {
 107                         int idx;
 108                         for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
 109                                 sb_bytenr = btrfs_sb_offset(idx);
 110                                 if (load_and_dump_sb(filename, fd,
 111                                                         sb_bytenr, full)) {
 112                                         close(fd);
 113                                         exit(1);
 114                                 }
 115
 116                                 putchar('\n');
 117                         }
 118                 } else {
 119                         load_and_dump_sb(filename, fd, sb_bytenr, full);
 120                         putchar('\n');
 121                 }
 122                 close(fd);
 123         }
 124
 125         exit(0);
 126 }
 127
 128 static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full)
 129 {
 130         u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
 131         struct btrfs_super_block *sb;
 132         u64 ret;
 133
 134         sb = (struct btrfs_super_block *)super_block_data;
 135
 136         ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
 137         if (ret != BTRFS_SUPER_INFO_SIZE) {
 138                 int e = errno;
 139
 140                 /* check if the disk if too short for further superblock */
 141                 if (ret == 0 && e == 0)
 142                         return 0;
 143
 144                 fprintf(stderr,
 145                    "ERROR: Failed to read the superblock on %s at %llu\n",
 146                    filename, (unsigned long long)sb_bytenr);
 147                 fprintf(stderr,
 148                    "ERROR: error = '%s', errno = %d\n", strerror(e), e);
 149                 return 1;
 150         }
 151         printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
 152         printf("---------------------------------------------------------\n");
 153         dump_superblock(sb, full);
 154         return 0;
 155 }
 156
 157 static int check_csum_sblock(void *sb, int csum_size)
 158 {
 159         char result[BTRFS_CSUM_SIZE];
 160         u32 crc = ~(u32)0;
 161
 162         crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
 163                                 crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 164         btrfs_csum_final(crc, result);
 165
 166         return !memcmp(sb, &result, csum_size);
 167 }
 168
 169 static void print_sys_chunk_array(struct btrfs_super_block *sb)
 170 {
 171         struct extent_buffer *buf;
 172         struct btrfs_disk_key *disk_key;
 173         struct btrfs_chunk *chunk;
 174         struct btrfs_key key;
 175         u8 *ptr, *array_end;
 176         u32 num_stripes;
 177         u32 len = 0;
 178         int i = 0;
 179
 180         buf = malloc(sizeof(*buf) + sizeof(*sb));
 181         if (!buf) {
 182                 fprintf(stderr, "%s\n", strerror(ENOMEM));
 183                 exit(1);
 184         }
 185         write_extent_buffer(buf, sb, 0, sizeof(*sb));
 186         ptr = sb->sys_chunk_array;
 187         array_end = ptr + btrfs_super_sys_array_size(sb);
 188
 189         while (ptr < array_end) {
 190                 disk_key = (struct btrfs_disk_key *)ptr;
 191                 btrfs_disk_key_to_cpu(&key, disk_key);
 192
 193                 printf("\titem %d ", i);
 194                 btrfs_print_key(disk_key);
 195
 196                 len = sizeof(*disk_key);
 197                 putchar('\n');
 198                 ptr += len;
 199
 200                 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
 201                         chunk = (struct btrfs_chunk *)(ptr - (u8 *)sb);
 202                         print_chunk(buf, chunk);
 203                         num_stripes = btrfs_chunk_num_stripes(buf, chunk);
 204                         len = btrfs_chunk_item_size(num_stripes);
 205                 } else {
 206                         BUG();
 207                 }
 208
 209                 ptr += len;
 210                 i++;
 211         }
 212
 213         free(buf);
 214 }
 215
 216 static int empty_backup(struct btrfs_root_backup *backup)
 217 {
 218         if (backup == NULL ||
 219                 (backup->tree_root == 0 &&
 220                  backup->tree_root_gen == 0))
 221                 return 1;
 222         return 0;
 223 }
 224
 225 static void print_root_backup(struct btrfs_root_backup *backup)
 226 {
 227         printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
 228                         btrfs_backup_tree_root(backup),
 229                         btrfs_backup_tree_root_gen(backup),
 230                         btrfs_backup_tree_root_level(backup));
 231         printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
 232                         btrfs_backup_chunk_root(backup),
 233                         btrfs_backup_chunk_root_gen(backup),
 234                         btrfs_backup_chunk_root_level(backup));
 235         printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
 236                         btrfs_backup_extent_root(backup),
 237                         btrfs_backup_extent_root_gen(backup),
 238                         btrfs_backup_extent_root_level(backup));
 239         printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
 240                         btrfs_backup_fs_root(backup),
 241                         btrfs_backup_fs_root_gen(backup),
 242                         btrfs_backup_fs_root_level(backup));
 243         printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
 244                         btrfs_backup_dev_root(backup),
 245                         btrfs_backup_dev_root_gen(backup),
 246                         btrfs_backup_dev_root_level(backup));
 247         printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
 248                         btrfs_backup_csum_root(backup),
 249                         btrfs_backup_csum_root_gen(backup),
 250                         btrfs_backup_csum_root_level(backup));
 251
 252         printf("\t\tbackup_total_bytes:\t%llu\n",
 253                                         btrfs_backup_total_bytes(backup));
 254         printf("\t\tbackup_bytes_used:\t%llu\n",
 255                                         btrfs_backup_bytes_used(backup));
 256         printf("\t\tbackup_num_devices:\t%llu\n",
 257                                         btrfs_backup_num_devices(backup));
 258         putchar('\n');
 259 }
 260
 261 static void print_backup_roots(struct btrfs_super_block *sb)
 262 {
 263         struct btrfs_root_backup *backup;
 264         int i;
 265
 266         for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
 267                 backup = sb->super_roots + i;
 268                 if (!empty_backup(backup)) {
 269                         printf("\tbackup %d:\n", i);
 270                         print_root_backup(backup);
 271                 }
 272         }
 273 }
 274
 275 static void dump_superblock(struct btrfs_super_block *sb, int full)
 276 {
 277         int i;
 278         char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
 279         u8 *p;
 280
 281         printf("csum\t\t\t0x");
 282         for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)
 283                 printf("%02x", p[i]);
 284         if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
 285                 printf(" [match]");
 286         else
 287                 printf(" [DON'T MATCH]");
 288         putchar('\n');
 289
 290         printf("bytenr\t\t\t%llu\n",
 291                 (unsigned long long)btrfs_super_bytenr(sb));
 292         printf("flags\t\t\t0x%llx\n",
 293                 (unsigned long long)btrfs_super_flags(sb));
 294
 295         printf("magic\t\t\t");
 296         s = (char *) &sb->magic;
 297         for (i = 0; i < 8; i++)
 298                 putchar(isprint(s[i]) ? s[i] : '.');
 299         if (btrfs_super_magic(sb) == BTRFS_MAGIC)
 300                 printf(" [match]\n");
 301         else
 302                 printf(" [DON'T MATCH]\n");
 303
 304         uuid_unparse(sb->fsid, buf);
 305         printf("fsid\t\t\t%s\n", buf);
 306
 307         printf("label\t\t\t");
 308         s = sb->label;
 309         for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
 310                 putchar(isprint(s[i]) ? s[i] : '.');
 311         putchar('\n');
 312
 313         printf("generation\t\t%llu\n",
 314                (unsigned long long)btrfs_super_generation(sb));
 315         printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
 316         printf("sys_array_size\t\t%llu\n",
 317                (unsigned long long)btrfs_super_sys_array_size(sb));
 318         printf("chunk_root_generation\t%llu\n",
 319                (unsigned long long)btrfs_super_chunk_root_generation(sb));
 320         printf("root_level\t\t%llu\n",
 321                (unsigned long long)btrfs_super_root_level(sb));
 322         printf("chunk_root\t\t%llu\n",
 323                (unsigned long long)btrfs_super_chunk_root(sb));
 324         printf("chunk_root_level\t%llu\n",
 325                (unsigned long long)btrfs_super_chunk_root_level(sb));
 326         printf("log_root\t\t%llu\n",
 327                (unsigned long long)btrfs_super_log_root(sb));
 328         printf("log_root_transid\t%llu\n",
 329                (unsigned long long)btrfs_super_log_root_transid(sb));
 330         printf("log_root_level\t\t%llu\n",
 331                (unsigned long long)btrfs_super_log_root_level(sb));
 332         printf("total_bytes\t\t%llu\n",
 333                (unsigned long long)btrfs_super_total_bytes(sb));
 334         printf("bytes_used\t\t%llu\n",
 335                (unsigned long long)btrfs_super_bytes_used(sb));
 336         printf("sectorsize\t\t%llu\n",
 337                (unsigned long long)btrfs_super_sectorsize(sb));
 338         printf("nodesize\t\t%llu\n",
 339                (unsigned long long)btrfs_super_nodesize(sb));
 340         printf("leafsize\t\t%llu\n",
 341                (unsigned long long)btrfs_super_leafsize(sb));
 342         printf("stripesize\t\t%llu\n",
 343                (unsigned long long)btrfs_super_stripesize(sb));
 344         printf("root_dir\t\t%llu\n",
 345                (unsigned long long)btrfs_super_root_dir(sb));
 346         printf("num_devices\t\t%llu\n",
 347                (unsigned long long)btrfs_super_num_devices(sb));
 348         printf("compat_flags\t\t0x%llx\n",
 349                (unsigned long long)btrfs_super_compat_flags(sb));
 350         printf("compat_ro_flags\t\t0x%llx\n",
 351                (unsigned long long)btrfs_super_compat_ro_flags(sb));
 352         printf("incompat_flags\t\t0x%llx\n",
 353                (unsigned long long)btrfs_super_incompat_flags(sb));
 354         printf("csum_type\t\t%llu\n",
 355                (unsigned long long)btrfs_super_csum_type(sb));
 356         printf("csum_size\t\t%llu\n",
 357                (unsigned long long)btrfs_super_csum_size(sb));
 358         printf("cache_generation\t%llu\n",
 359                (unsigned long long)btrfs_super_cache_generation(sb));
 360         printf("uuid_tree_generation\t%llu\n",
 361                (unsigned long long)btrfs_super_uuid_tree_generation(sb));
 362
 363         uuid_unparse(sb->dev_item.uuid, buf);
 364         printf("dev_item.uuid\t\t%s\n", buf);
 365
 366         uuid_unparse(sb->dev_item.fsid, buf);
 367         printf("dev_item.fsid\t\t%s %s\n", buf,
 368                 !memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
 369                         "[match]" : "[DON'T MATCH]");
 370
 371         printf("dev_item.type\t\t%llu\n", (unsigned long long)
 372                btrfs_stack_device_type(&sb->dev_item));
 373         printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
 374                btrfs_stack_device_total_bytes(&sb->dev_item));
 375         printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
 376                btrfs_stack_device_bytes_used(&sb->dev_item));
 377         printf("dev_item.io_align\t%u\n", (unsigned int)
 378                btrfs_stack_device_io_align(&sb->dev_item));
 379         printf("dev_item.io_width\t%u\n", (unsigned int)
 380                btrfs_stack_device_io_width(&sb->dev_item));
 381         printf("dev_item.sector_size\t%u\n", (unsigned int)
 382                btrfs_stack_device_sector_size(&sb->dev_item));
 383         printf("dev_item.devid\t\t%llu\n",
 384                btrfs_stack_device_id(&sb->dev_item));
 385         printf("dev_item.dev_group\t%u\n", (unsigned int)
 386                btrfs_stack_device_group(&sb->dev_item));
 387         printf("dev_item.seek_speed\t%u\n", (unsigned int)
 388                btrfs_stack_device_seek_speed(&sb->dev_item));
 389         printf("dev_item.bandwidth\t%u\n", (unsigned int)
 390                btrfs_stack_device_bandwidth(&sb->dev_item));
 391         printf("dev_item.generation\t%llu\n", (unsigned long long)
 392                btrfs_stack_device_generation(&sb->dev_item));
 393         if (full) {
 394                 printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
 395                 print_sys_chunk_array(sb);
 396                 printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
 397                 print_backup_roots(sb);
 398         }
 399 }