btrfs-progs/btrfs-show-super.c
Eric Sandeen fd518cfcb1 btrfs-show-super: don't try to print not-superblocks
If we point btrfs-show-super at a not-btrfs-device and
try to print all superblocks, bad things are apt to happen:

superblock: bytenr=274877906944, device=/dev/sdc2
---------------------------------------------------------
btrfs-show-super: ctree.h:1984: btrfs_super_csum_size: \
Assertion `!(t >= (sizeof(btrfs_csum_sizes) / sizeof((btrfs_csum_sizes)[0])))' failed.
csum			0xAborted

Don't try to print superblocks that don't look like superblocks,
and add an "-f" (force) option to try anyway, if the user
really wants to give it a shot.

Fix some spelling & capitalization while we're at it.

The manpage says that if any problem happens, 1 will
be returned, but that's already not true today LOL, so
I didn't bother to make it true when we detect bad
sb magic, either...

I figure it's worth continuing and trying all superblocks
in case just one has a corrupt magic.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[renamed -f to -F due to clash with existing option, converted
relevant docs to asciidoc]
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-08-22 14:39:31 +02:00

412 lines
12 KiB
C

/*
* Copyright (C) 2012 STRATO AG. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#define _XOPEN_SOURCE 500
#define _GNU_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <ctype.h>
#include <uuid/uuid.h>
#include <errno.h>
#include "kerncompat.h"
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "list.h"
#include "version.h"
#include "utils.h"
#include "crc32c.h"
static void print_usage(void);
static void dump_superblock(struct btrfs_super_block *sb, int full);
int main(int argc, char **argv);
static int load_and_dump_sb(char *, int fd, u64 sb_bytenr, int full, int force);
static void print_usage(void)
{
fprintf(stderr,
"usage: btrfs-show-super [-i super_mirror|-a|-f|-F] dev [dev..]\n");
fprintf(stderr, "\t-f : print full superblock information\n");
fprintf(stderr, "\t-a : print information of all superblocks\n");
fprintf(stderr, "\t-i <super_mirror> : specify which mirror to print out\n");
fprintf(stderr, "\t-F : attempt to dump superblocks with bad magic\n");
fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
}
int main(int argc, char **argv)
{
int opt;
int all = 0;
int full = 0;
int force = 0;
char *filename;
int fd = -1;
int i;
u64 arg;
u64 sb_bytenr = btrfs_sb_offset(0);
while ((opt = getopt(argc, argv, "fFai:")) != -1) {
switch (opt) {
case 'i':
arg = arg_strtou64(optarg);
if (arg >= BTRFS_SUPER_MIRROR_MAX) {
fprintf(stderr,
"Illegal super_mirror %llu\n",
arg);
print_usage();
exit(1);
}
sb_bytenr = btrfs_sb_offset(arg);
break;
case 'a':
all = 1;
break;
case 'f':
full = 1;
break;
case 'F':
force = 1;
break;
default:
print_usage();
exit(1);
}
}
if (argc < optind + 1) {
print_usage();
exit(1);
}
for (i = optind; i < argc; i++) {
filename = argv[i];
fd = open(filename, O_RDONLY, 0666);
if (fd < 0) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
if (all) {
int idx;
for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
sb_bytenr = btrfs_sb_offset(idx);
if (load_and_dump_sb(filename, fd,
sb_bytenr, full, force)) {
close(fd);
exit(1);
}
putchar('\n');
}
} else {
load_and_dump_sb(filename, fd, sb_bytenr, full, force);
putchar('\n');
}
close(fd);
}
exit(0);
}
static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full,
int force)
{
u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
struct btrfs_super_block *sb;
u64 ret;
sb = (struct btrfs_super_block *)super_block_data;
ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
if (ret != BTRFS_SUPER_INFO_SIZE) {
int e = errno;
/* check if the disk if too short for further superblock */
if (ret == 0 && e == 0)
return 0;
fprintf(stderr,
"ERROR: Failed to read the superblock on %s at %llu\n",
filename, (unsigned long long)sb_bytenr);
fprintf(stderr,
"ERROR: error = '%s', errno = %d\n", strerror(e), e);
return 1;
}
printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
printf("---------------------------------------------------------\n");
if (btrfs_super_magic(sb) != BTRFS_MAGIC && !force) {
fprintf(stderr,
"ERROR: bad magic on superblock on %s at %llu\n",
filename, (unsigned long long)sb_bytenr);
} else {
dump_superblock(sb, full);
}
return 0;
}
static int check_csum_sblock(void *sb, int csum_size)
{
char result[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, result);
return !memcmp(sb, &result, csum_size);
}
static void print_sys_chunk_array(struct btrfs_super_block *sb)
{
struct extent_buffer *buf;
struct btrfs_disk_key *disk_key;
struct btrfs_chunk *chunk;
struct btrfs_key key;
u8 *ptr, *array_end;
u32 num_stripes;
u32 len = 0;
int i = 0;
buf = malloc(sizeof(*buf) + sizeof(*sb));
if (!buf) {
fprintf(stderr, "%s\n", strerror(ENOMEM));
exit(1);
}
write_extent_buffer(buf, sb, 0, sizeof(*sb));
ptr = sb->sys_chunk_array;
array_end = ptr + btrfs_super_sys_array_size(sb);
while (ptr < array_end) {
disk_key = (struct btrfs_disk_key *)ptr;
btrfs_disk_key_to_cpu(&key, disk_key);
printf("\titem %d ", i);
btrfs_print_key(disk_key);
len = sizeof(*disk_key);
putchar('\n');
ptr += len;
if (key.type == BTRFS_CHUNK_ITEM_KEY) {
chunk = (struct btrfs_chunk *)(ptr - (u8 *)sb);
print_chunk(buf, chunk);
num_stripes = btrfs_chunk_num_stripes(buf, chunk);
len = btrfs_chunk_item_size(num_stripes);
} else {
BUG();
}
ptr += len;
i++;
}
free(buf);
}
static int empty_backup(struct btrfs_root_backup *backup)
{
if (backup == NULL ||
(backup->tree_root == 0 &&
backup->tree_root_gen == 0))
return 1;
return 0;
}
static void print_root_backup(struct btrfs_root_backup *backup)
{
printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_tree_root(backup),
btrfs_backup_tree_root_gen(backup),
btrfs_backup_tree_root_level(backup));
printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_chunk_root(backup),
btrfs_backup_chunk_root_gen(backup),
btrfs_backup_chunk_root_level(backup));
printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_extent_root(backup),
btrfs_backup_extent_root_gen(backup),
btrfs_backup_extent_root_level(backup));
printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_fs_root(backup),
btrfs_backup_fs_root_gen(backup),
btrfs_backup_fs_root_level(backup));
printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_dev_root(backup),
btrfs_backup_dev_root_gen(backup),
btrfs_backup_dev_root_level(backup));
printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
btrfs_backup_csum_root(backup),
btrfs_backup_csum_root_gen(backup),
btrfs_backup_csum_root_level(backup));
printf("\t\tbackup_total_bytes:\t%llu\n",
btrfs_backup_total_bytes(backup));
printf("\t\tbackup_bytes_used:\t%llu\n",
btrfs_backup_bytes_used(backup));
printf("\t\tbackup_num_devices:\t%llu\n",
btrfs_backup_num_devices(backup));
putchar('\n');
}
static void print_backup_roots(struct btrfs_super_block *sb)
{
struct btrfs_root_backup *backup;
int i;
for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
backup = sb->super_roots + i;
if (!empty_backup(backup)) {
printf("\tbackup %d:\n", i);
print_root_backup(backup);
}
}
}
static void dump_superblock(struct btrfs_super_block *sb, int full)
{
int i;
char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
u8 *p;
printf("csum\t\t\t0x");
for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)
printf("%02x", p[i]);
if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
printf(" [match]");
else
printf(" [DON'T MATCH]");
putchar('\n');
printf("bytenr\t\t\t%llu\n",
(unsigned long long)btrfs_super_bytenr(sb));
printf("flags\t\t\t0x%llx\n",
(unsigned long long)btrfs_super_flags(sb));
printf("magic\t\t\t");
s = (char *) &sb->magic;
for (i = 0; i < 8; i++)
putchar(isprint(s[i]) ? s[i] : '.');
if (btrfs_super_magic(sb) == BTRFS_MAGIC)
printf(" [match]\n");
else
printf(" [DON'T MATCH]\n");
uuid_unparse(sb->fsid, buf);
printf("fsid\t\t\t%s\n", buf);
printf("label\t\t\t");
s = sb->label;
for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
putchar(isprint(s[i]) ? s[i] : '.');
putchar('\n');
printf("generation\t\t%llu\n",
(unsigned long long)btrfs_super_generation(sb));
printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
printf("sys_array_size\t\t%llu\n",
(unsigned long long)btrfs_super_sys_array_size(sb));
printf("chunk_root_generation\t%llu\n",
(unsigned long long)btrfs_super_chunk_root_generation(sb));
printf("root_level\t\t%llu\n",
(unsigned long long)btrfs_super_root_level(sb));
printf("chunk_root\t\t%llu\n",
(unsigned long long)btrfs_super_chunk_root(sb));
printf("chunk_root_level\t%llu\n",
(unsigned long long)btrfs_super_chunk_root_level(sb));
printf("log_root\t\t%llu\n",
(unsigned long long)btrfs_super_log_root(sb));
printf("log_root_transid\t%llu\n",
(unsigned long long)btrfs_super_log_root_transid(sb));
printf("log_root_level\t\t%llu\n",
(unsigned long long)btrfs_super_log_root_level(sb));
printf("total_bytes\t\t%llu\n",
(unsigned long long)btrfs_super_total_bytes(sb));
printf("bytes_used\t\t%llu\n",
(unsigned long long)btrfs_super_bytes_used(sb));
printf("sectorsize\t\t%llu\n",
(unsigned long long)btrfs_super_sectorsize(sb));
printf("nodesize\t\t%llu\n",
(unsigned long long)btrfs_super_nodesize(sb));
printf("leafsize\t\t%llu\n",
(unsigned long long)btrfs_super_leafsize(sb));
printf("stripesize\t\t%llu\n",
(unsigned long long)btrfs_super_stripesize(sb));
printf("root_dir\t\t%llu\n",
(unsigned long long)btrfs_super_root_dir(sb));
printf("num_devices\t\t%llu\n",
(unsigned long long)btrfs_super_num_devices(sb));
printf("compat_flags\t\t0x%llx\n",
(unsigned long long)btrfs_super_compat_flags(sb));
printf("compat_ro_flags\t\t0x%llx\n",
(unsigned long long)btrfs_super_compat_ro_flags(sb));
printf("incompat_flags\t\t0x%llx\n",
(unsigned long long)btrfs_super_incompat_flags(sb));
printf("csum_type\t\t%llu\n",
(unsigned long long)btrfs_super_csum_type(sb));
printf("csum_size\t\t%llu\n",
(unsigned long long)btrfs_super_csum_size(sb));
printf("cache_generation\t%llu\n",
(unsigned long long)btrfs_super_cache_generation(sb));
printf("uuid_tree_generation\t%llu\n",
(unsigned long long)btrfs_super_uuid_tree_generation(sb));
uuid_unparse(sb->dev_item.uuid, buf);
printf("dev_item.uuid\t\t%s\n", buf);
uuid_unparse(sb->dev_item.fsid, buf);
printf("dev_item.fsid\t\t%s %s\n", buf,
!memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
"[match]" : "[DON'T MATCH]");
printf("dev_item.type\t\t%llu\n", (unsigned long long)
btrfs_stack_device_type(&sb->dev_item));
printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
btrfs_stack_device_total_bytes(&sb->dev_item));
printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
btrfs_stack_device_bytes_used(&sb->dev_item));
printf("dev_item.io_align\t%u\n", (unsigned int)
btrfs_stack_device_io_align(&sb->dev_item));
printf("dev_item.io_width\t%u\n", (unsigned int)
btrfs_stack_device_io_width(&sb->dev_item));
printf("dev_item.sector_size\t%u\n", (unsigned int)
btrfs_stack_device_sector_size(&sb->dev_item));
printf("dev_item.devid\t\t%llu\n",
btrfs_stack_device_id(&sb->dev_item));
printf("dev_item.dev_group\t%u\n", (unsigned int)
btrfs_stack_device_group(&sb->dev_item));
printf("dev_item.seek_speed\t%u\n", (unsigned int)
btrfs_stack_device_seek_speed(&sb->dev_item));
printf("dev_item.bandwidth\t%u\n", (unsigned int)
btrfs_stack_device_bandwidth(&sb->dev_item));
printf("dev_item.generation\t%llu\n", (unsigned long long)
btrfs_stack_device_generation(&sb->dev_item));
if (full) {
printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
print_sys_chunk_array(sb);
printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
print_backup_roots(sb);
}
}