busybox/util-linux/mkfs_reiser.c

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/* vi: set sw=4 ts=4: */
/*
* mkfs_reiser: utility to create ReiserFS filesystem
*
* Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//usage:#define mkfs_reiser_trivial_usage
//usage: "[-f] [-l LABEL] BLOCKDEV [4K-BLOCKS]"
//usage:#define mkfs_reiser_full_usage "\n\n"
//usage: "Make a ReiserFS V3 filesystem\n"
//usage: "\n -f Force"
//usage: "\n -l LBL Volume label"
#include "libbb.h"
#include <linux/fs.h>
char BUG_wrong_field_size(void);
#define STORE_LE(field, value) \
do { \
if (sizeof(field) == 4) \
field = SWAP_LE32(value); \
else if (sizeof(field) == 2) \
field = SWAP_LE16(value); \
else if (sizeof(field) == 1) \
field = (value); \
else \
BUG_wrong_field_size(); \
} while (0)
#define FETCH_LE32(field) \
(sizeof(field) == 4 ? SWAP_LE32(field) : BUG_wrong_field_size())
struct journal_params {
uint32_t jp_journal_1st_block; /* where does journal start from on its device */
uint32_t jp_journal_dev; /* journal device st_rdev */
uint32_t jp_journal_size; /* size of the journal on FS creation. used to make sure they don't overflow it */
uint32_t jp_journal_trans_max; /* max number of blocks in a transaction. */
uint32_t jp_journal_magic; /* random value made on fs creation (this was sb_journal_block_count) */
uint32_t jp_journal_max_batch; /* max number of blocks to batch into a trans */
uint32_t jp_journal_max_commit_age; /* in seconds, how old can an async commit be */
uint32_t jp_journal_max_trans_age; /* in seconds, how old can a transaction be */
};
struct reiserfs_journal_header {
uint32_t jh_last_flush_trans_id; /* id of last fully flushed transaction */
uint32_t jh_first_unflushed_offset; /* offset in the log of where to start replay after a crash */
uint32_t jh_mount_id;
struct journal_params jh_journal;
uint32_t jh_last_check_mount_id; /* the mount id of the fs during the last reiserfsck --check. */
};
struct reiserfs_super_block {
uint32_t sb_block_count; /* 0 number of block on data device */
uint32_t sb_free_blocks; /* 4 free blocks count */
uint32_t sb_root_block; /* 8 root of the tree */
struct journal_params sb_journal; /* 12 */
uint16_t sb_blocksize; /* 44 */
uint16_t sb_oid_maxsize; /* 46 max size of object id array, see get_objectid() commentary */
uint16_t sb_oid_cursize; /* 48 current size of object id array */
uint16_t sb_umount_state; /* 50 this is set to 1 when filesystem was umounted, to 2 - when not */
char s_magic[10]; /* 52 "ReIsErFs" or "ReIsEr2Fs" or "ReIsEr3Fs" */
uint16_t sb_fs_state; /* 62 it is set to used by fsck to mark which phase of rebuilding is done (used for fsck debugging) */
uint32_t sb_hash_function_code; /* 64 code of fuction which was/is/will be used to sort names in a directory. See codes in above */
uint16_t sb_tree_height; /* 68 height of filesytem tree. Tree consisting of only one root block has 2 here */
uint16_t sb_bmap_nr; /* 70 amount of bitmap blocks needed to address each block of file system */
uint16_t sb_version; /* 72 this field is only reliable on filesystem with non-standard journal */
uint16_t sb_reserved_for_journal; /* 74 size in blocks of journal area on main device, we need to keep after non-standard journal relocation */
uint32_t sb_inode_generation; /* 76 */
uint32_t sb_flags; /* 80 Right now used only by inode-attributes, if enabled */
unsigned char s_uuid[16]; /* 84 filesystem unique identifier */
unsigned char s_label[16]; /* 100 filesystem volume label */
uint16_t sb_mnt_count; /* 116 */
uint16_t sb_max_mnt_count; /* 118 */
uint32_t sb_lastcheck; /* 120 */
uint32_t sb_check_interval; /* 124 */
/* zero filled by mkreiserfs and reiserfs_convert_objectid_map_v1() so any additions must be updated there as well. */
char s_unused[76]; /* 128 */
/* 204 */
};
/* Header of a disk block. More precisely, header of a formatted leaf
or internal node, and not the header of an unformatted node. */
struct block_head {
uint16_t blk2_level; /* Level of a block in the tree. */
uint16_t blk2_nr_item; /* Number of keys/items in a block. */
uint16_t blk2_free_space; /* Block free space in bytes. */
uint16_t blk_reserved;
uint32_t reserved[4];
};
#define REISERFS_DISK_OFFSET_IN_BYTES (64 * 1024)
#define REISERFS_3_6_SUPER_MAGIC_STRING "ReIsEr2Fs"
#define REISERFS_FORMAT_3_6 2
#define DEFAULT_MAX_MNT_COUNT 30 /* 30 mounts */
#define DEFAULT_CHECK_INTERVAL (180 * 60 * 60 * 24) /* 180 days */
#define FS_CLEANLY_UMOUNTED 1 /* this was REISERFS_VALID_FS */
#define JOURNAL_MIN_SIZE 512
/* biggest possible single transaction, don't change for now (8/3/99) */
#define JOURNAL_TRANS_MAX 1024
#define JOURNAL_TRANS_MIN 256 /* need to check whether it works */
#define JOURNAL_DEFAULT_RATIO 8 /* default journal size / max trans length */
#define JOURNAL_MIN_RATIO 2
/* max blocks to batch into one transaction, don't make this any bigger than 900 */
#define JOURNAL_MAX_BATCH 900
#define JOURNAL_MAX_COMMIT_AGE 30
// Standard mkreiserfs 3.6.21:
// -b | --block-size N size of file-system block, in bytes
// -j | --journal-device FILE path to separate device to hold journal
// -s | --journal-size N size of the journal in blocks
// -o | --journal-offset N offset of the journal from the start of
// the separate device, in blocks
// -t | --transaction-max-size N maximal size of transaction, in blocks
// -B | --badblocks file store all bad blocks given in file on the fs
// -h | --hash rupasov|tea|r5 hash function to use by default
// -u | --uuid UUID store UUID in the superblock
// -l | --label LABEL store LABEL in the superblock
// --format 3.5|3.6 old 3.5 format or newer 3.6
// -f | --force specified once, make mkreiserfs the whole
// disk, not block device or mounted partition;
// specified twice, do not ask for confirmation
// -q | --quiet quiet work without messages, progress and
// questions. Useful if run in a script. For use
// by end users only.
// -d | --debug print debugging information during mkreiser
// -V print version and exit
// Options not commented below are taken but silently ignored:
enum {
OPT_b = 1 << 0,
OPT_j = 1 << 1,
OPT_s = 1 << 2,
OPT_o = 1 << 3,
OPT_t = 1 << 4,
OPT_B = 1 << 5,
OPT_h = 1 << 6,
OPT_u = 1 << 7,
OPT_l = 1 << 8, // label
OPT_f = 1 << 9, // ask no questions
OPT_q = 1 << 10,
OPT_d = 1 << 11,
//OPT_V = 1 << 12, // -V version. bbox applets don't support that
};
int mkfs_reiser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mkfs_reiser_main(int argc UNUSED_PARAM, char **argv)
{
unsigned blocksize = 4096;
unsigned journal_blocks = 8192;
unsigned blocks, bitmap_blocks, i, block;
time_t timestamp;
const char *label = "";
struct stat st;
int fd;
uint8_t *buf;
struct reiserfs_super_block *sb;
struct journal_params *jp;
struct block_head *root;
// using global "option_mask32" instead of local "opts":
// we are register starved here
opt_complementary = "-1:b+";
/*opts =*/ getopt32(argv, "b:j:s:o:t:B:h:u:l:fqd",
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &label);
argv += optind; // argv[0] -- device
// check the device is a block device
fd = xopen(argv[0], O_WRONLY | O_EXCL);
xfstat(fd, &st, argv[0]);
if (!S_ISBLK(st.st_mode) && !(option_mask32 & OPT_f))
bb_error_msg_and_die("%s: not a block device", argv[0]);
// check if it is mounted
// N.B. what if we format a file? find_mount_point will return false negative since
// it is loop block device which is mounted!
if (find_mount_point(argv[0], 0))
bb_error_msg_and_die("can't format mounted filesystem");
// open the device, get size in blocks
blocks = get_volume_size_in_bytes(fd, argv[1], blocksize, /*extend:*/ 1) / blocksize;
// block number sanity check
// we have a limit: skipped area, super block, journal and root block
// all have to be addressed by one first bitmap
block = REISERFS_DISK_OFFSET_IN_BYTES / blocksize // boot area
+ 1 // sb
+ 1 // bitmap#0
+ journal_blocks+1 // journal
;
// count overhead
bitmap_blocks = (blocks - 1) / (blocksize * 8) + 1;
i = block + bitmap_blocks;
// check overhead
if (MIN(blocksize * 8, blocks) < i)
bb_error_msg_and_die("need >= %u blocks", i);
// ask confirmation?
// TODO: ???
// wipe out first REISERFS_DISK_OFFSET_IN_BYTES of device
// TODO: do we really need to wipe?!
xlseek(fd, REISERFS_DISK_OFFSET_IN_BYTES, SEEK_SET);
// fill superblock
sb = (struct reiserfs_super_block *)xzalloc(blocksize);
// block count
STORE_LE(sb->sb_block_count, blocks);
STORE_LE(sb->sb_free_blocks, blocks - i);
// TODO: decypher!
STORE_LE(sb->sb_root_block, block);
// fill journal related fields
jp = &sb->sb_journal;
STORE_LE(jp->jp_journal_1st_block, REISERFS_DISK_OFFSET_IN_BYTES / blocksize + 1/*sb*/ + 1/*bmp#0*/);
timestamp = time(NULL);
srand(timestamp);
STORE_LE(jp->jp_journal_magic, rand());
STORE_LE(jp->jp_journal_size, journal_blocks);
STORE_LE(jp->jp_journal_trans_max, JOURNAL_TRANS_MAX);
STORE_LE(jp->jp_journal_max_batch, JOURNAL_MAX_BATCH);
STORE_LE(jp->jp_journal_max_commit_age, JOURNAL_MAX_COMMIT_AGE);
// sizes
STORE_LE(sb->sb_blocksize, blocksize);
STORE_LE(sb->sb_oid_maxsize, (blocksize - sizeof(*sb)) / sizeof(uint32_t) / 2 * 2);
STORE_LE(sb->sb_oid_cursize, 2); // "." and ".."
strcpy(sb->s_magic, REISERFS_3_6_SUPER_MAGIC_STRING);
STORE_LE(sb->sb_bmap_nr, (bitmap_blocks > ((1LL << 16) - 1)) ? 0 : bitmap_blocks);
// misc
STORE_LE(sb->sb_version, REISERFS_FORMAT_3_6);
STORE_LE(sb->sb_lastcheck, timestamp);
STORE_LE(sb->sb_check_interval, DEFAULT_CHECK_INTERVAL);
STORE_LE(sb->sb_mnt_count, 1);
STORE_LE(sb->sb_max_mnt_count, DEFAULT_MAX_MNT_COUNT);
STORE_LE(sb->sb_umount_state, FS_CLEANLY_UMOUNTED);
STORE_LE(sb->sb_tree_height, 2);
STORE_LE(sb->sb_hash_function_code, 3); // R5_HASH
STORE_LE(sb->sb_flags, 1);
//STORE_LE(sb->sb_reserved_for_journal, 0);
// create UUID
generate_uuid(sb->s_uuid);
// write the label
safe_strncpy((char *)sb->s_label, label, sizeof(sb->s_label));
// TODO: EMPIRIC! ENDIANNESS!
// superblock has only 204 bytes. What are these?
buf = (uint8_t *)sb;
buf[205] = 1;
buf[209] = 3;
// put superblock
xwrite(fd, sb, blocksize);
// create bitmaps
buf = xzalloc(blocksize);
// bitmap #0 uses initial "block"+1 blocks
i = block + 1;
memset(buf, 0xFF, i / 8);
buf[i / 8] = (1 << (i & 7)) - 1; //0..7 => 00000000..01111111
// mark trailing absent blocks, if any
if (blocks < 8*blocksize) {
unsigned n = 8*blocksize - blocks;
i = n / 8;
buf[blocksize - i - 1] |= 0x7F00 >> (n & 7); //0..7 => 00000000..11111110
memset(buf + blocksize - i, 0xFF, i); // N.B. no overflow here!
}
// put bitmap #0
xwrite(fd, buf, blocksize);
// now go journal blocks
memset(buf, 0, blocksize);
for (i = 0; i < journal_blocks; i++)
xwrite(fd, buf, blocksize);
// dump journal control block
memcpy(&((struct reiserfs_journal_header *)buf)->jh_journal, &sb->sb_journal, sizeof(sb->sb_journal));
xwrite(fd, buf, blocksize);
// other bitmaps are in every (8*blocksize)-th block
// N.B. they use the only block -- namely bitmap itself!
buf[0] = 0x01;
// put bitmaps
for (i = 1; i < bitmap_blocks; i++) {
xlseek(fd, i*8*blocksize * blocksize, SEEK_SET);
// mark trailing absent blocks, if any
if (i == bitmap_blocks - 1 && (blocks % (8*blocksize))) {
unsigned n = 8*blocksize - blocks % (8*blocksize);
unsigned j = n / 8;
buf[blocksize - j - 1] |= 0x7F00 >> (n & 7); //0..7 => 00000000..11111110
memset(buf + blocksize - j, 0xFF, j); // N.B. no overflow here!
}
xwrite(fd, buf, blocksize);
}
// fill root block
// block head
memset(buf, 0, blocksize);
root = (struct block_head *)buf;
STORE_LE(root->blk2_level, 1); // leaf node
STORE_LE(root->blk2_nr_item, 2); // "." and ".."
STORE_LE(root->blk2_free_space, blocksize - sizeof(struct block_head));
// item head
// root directory
// TODO: EMPIRIC! ENDIANNESS!
// TODO: indented assignments seem to be timestamps
buf[4] = 0134;
buf[24] = 01;
buf[28] = 02;
buf[42] = 054;
buf[44] = 0324;
buf[45] = 017;
buf[46] = 01;
buf[48] = 01;
buf[52] = 02;
buf[56] = 01;
buf[60] = 0364;
buf[61] = 01;
buf[64] = 02;
buf[66] = 060;
buf[68] = 0244;
buf[69] = 017;
buf[4004] = 01;
buf[4008] = 01;
buf[4012] = 02;
buf[4016] = 050;
buf[4018] = 04;
buf[4020] = 02;
buf[4028] = 01;
buf[4032] = 040;
buf[4034] = 04;
buf[4036] = 056; buf[4037] = 056; // ".."
buf[4044] = 056; // "."
buf[4052] = 0355;
buf[4053] = 0101;
buf[4056] = 03;
buf[4060] = 060;
buf[4076] = 0173;
buf[4077] = 0240;
buf[4078] = 0344;
buf[4079] = 0112;
buf[4080] = 0173;
buf[4081] = 0240;
buf[4082] = 0344;
buf[4083] = 0112;
buf[4084] = 0173;
buf[4085] = 0240;
buf[4086] = 0344;
buf[4087] = 0112;
buf[4088] = 01;
// put root block
xlseek(fd, block * blocksize, SEEK_SET);
xwrite(fd, buf, blocksize);
// cleanup
if (ENABLE_FEATURE_CLEAN_UP) {
free(buf);
free(sb);
}
xclose(fd);
return EXIT_SUCCESS;
}