busybox/util-linux/mkfs_minix.c
2008-11-22 18:58:11 +00:00

735 lines
19 KiB
C

/* vi: set sw=4 ts=4: */
/*
* mkfs.c - make a linux (minix) file-system.
*
* (C) 1991 Linus Torvalds. This file may be redistributed as per
* the Linux copyright.
*/
/*
* DD.MM.YY
*
* 24.11.91 - Time began. Used the fsck sources to get started.
*
* 25.11.91 - Corrected some bugs. Added support for ".badblocks"
* The algorithm for ".badblocks" is a bit weird, but
* it should work. Oh, well.
*
* 25.01.92 - Added the -l option for getting the list of bad blocks
* out of a named file. (Dave Rivers, rivers@ponds.uucp)
*
* 28.02.92 - Added %-information when using -c.
*
* 28.02.93 - Added support for other namelengths than the original
* 14 characters so that I can test the new kernel routines..
*
* 09.10.93 - Make exit status conform to that required by fsutil
* (Rik Faith, faith@cs.unc.edu)
*
* 31.10.93 - Added inode request feature, for backup floppies: use
* 32 inodes, for a news partition use more.
* (Scott Heavner, sdh@po.cwru.edu)
*
* 03.01.94 - Added support for file system valid flag.
* (Dr. Wettstein, greg%wind.uucp@plains.nodak.edu)
*
* 30.10.94 - added support for v2 filesystem
* (Andreas Schwab, schwab@issan.informatik.uni-dortmund.de)
*
* 09.11.94 - Added test to prevent overwrite of mounted fs adapted
* from Theodore Ts'o's (tytso@athena.mit.edu) mke2fs
* program. (Daniel Quinlan, quinlan@yggdrasil.com)
*
* 03.20.95 - Clear first 512 bytes of filesystem to make certain that
* the filesystem is not misidentified as a MS-DOS FAT filesystem.
* (Daniel Quinlan, quinlan@yggdrasil.com)
*
* 02.07.96 - Added small patch from Russell King to make the program a
* good deal more portable (janl@math.uio.no)
*
* Usage: mkfs [-c | -l filename ] [-v] [-nXX] [-iXX] device [size-in-blocks]
*
* -c for readability checking (SLOW!)
* -l for getting a list of bad blocks from a file.
* -n for namelength (currently the kernel only uses 14 or 30)
* -i for number of inodes
* -v for v2 filesystem
*
* The device may be a block device or a image of one, but this isn't
* enforced (but it's not much fun on a character device :-).
*
* Modified for BusyBox by Erik Andersen <andersen@debian.org> --
* removed getopt based parser and added a hand rolled one.
*/
#include "libbb.h"
#include <mntent.h>
#include "minix.h"
/* Store the very same times/uids/gids for image consistency */
#if 1
# define CUR_TIME 0
# define GETUID 0
# define GETGID 0
#else
/* Was using this. Is it useful? NB: this will break testsuite */
# define CUR_TIME time(NULL)
# define GETUID getuid()
# define GETGID getgid()
#endif
enum {
MAX_GOOD_BLOCKS = 512,
TEST_BUFFER_BLOCKS = 16,
};
#if !ENABLE_FEATURE_MINIX2
enum { version2 = 0 };
#endif
enum { dev_fd = 3 };
struct globals {
#if ENABLE_FEATURE_MINIX2
smallint version2;
#define version2 G.version2
#endif
char *device_name;
uint32_t total_blocks;
int badblocks;
int namelen;
int dirsize;
int magic;
char *inode_buffer;
char *inode_map;
char *zone_map;
int used_good_blocks;
unsigned long req_nr_inodes;
unsigned currently_testing;
char root_block[BLOCK_SIZE];
char superblock_buffer[BLOCK_SIZE];
char boot_block_buffer[512];
unsigned short good_blocks_table[MAX_GOOD_BLOCKS];
/* check_blocks(): buffer[] was the biggest static in entire bbox */
char check_blocks_buffer[BLOCK_SIZE * TEST_BUFFER_BLOCKS];
unsigned short ind_block1[BLOCK_SIZE >> 1];
unsigned short dind_block1[BLOCK_SIZE >> 1];
unsigned long ind_block2[BLOCK_SIZE >> 2];
unsigned long dind_block2[BLOCK_SIZE >> 2];
};
#define G (*ptr_to_globals)
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
} while (0)
static ALWAYS_INLINE unsigned div_roundup(unsigned size, unsigned n)
{
return (size + n-1) / n;
}
#define INODE_BUF1 (((struct minix1_inode*)G.inode_buffer) - 1)
#define INODE_BUF2 (((struct minix2_inode*)G.inode_buffer) - 1)
#define SB (*(struct minix_superblock*)G.superblock_buffer)
#define SB_INODES (SB.s_ninodes)
#define SB_IMAPS (SB.s_imap_blocks)
#define SB_ZMAPS (SB.s_zmap_blocks)
#define SB_FIRSTZONE (SB.s_firstdatazone)
#define SB_ZONE_SIZE (SB.s_log_zone_size)
#define SB_MAXSIZE (SB.s_max_size)
#define SB_MAGIC (SB.s_magic)
#if !ENABLE_FEATURE_MINIX2
# define SB_ZONES (SB.s_nzones)
# define INODE_BLOCKS div_roundup(SB_INODES, MINIX1_INODES_PER_BLOCK)
#else
# define SB_ZONES (version2 ? SB.s_zones : SB.s_nzones)
# define INODE_BLOCKS div_roundup(SB_INODES, \
(version2 ? MINIX2_INODES_PER_BLOCK : MINIX1_INODES_PER_BLOCK))
#endif
#define INODE_BUFFER_SIZE (INODE_BLOCKS * BLOCK_SIZE)
#define NORM_FIRSTZONE (2 + SB_IMAPS + SB_ZMAPS + INODE_BLOCKS)
/* Before you ask "where they come from?": */
/* setbit/clrbit are supplied by sys/param.h */
static int minix_bit(const char* a, unsigned i)
{
return a[i >> 3] & (1<<(i & 7));
}
static void minix_setbit(char *a, unsigned i)
{
setbit(a, i);
}
static void minix_clrbit(char *a, unsigned i)
{
clrbit(a, i);
}
/* Note: do not assume 0/1, it is 0/nonzero */
#define zone_in_use(x) minix_bit(G.zone_map,(x)-SB_FIRSTZONE+1)
/*#define inode_in_use(x) minix_bit(G.inode_map,(x))*/
#define mark_inode(x) minix_setbit(G.inode_map,(x))
#define unmark_inode(x) minix_clrbit(G.inode_map,(x))
#define mark_zone(x) minix_setbit(G.zone_map,(x)-SB_FIRSTZONE+1)
#define unmark_zone(x) minix_clrbit(G.zone_map,(x)-SB_FIRSTZONE+1)
#ifndef BLKGETSIZE
# define BLKGETSIZE _IO(0x12,96) /* return device size */
#endif
static long valid_offset(int fd, int offset)
{
char ch;
if (lseek(fd, offset, SEEK_SET) < 0)
return 0;
if (read(fd, &ch, 1) < 1)
return 0;
return 1;
}
static int count_blocks(int fd)
{
int high, low;
low = 0;
for (high = 1; valid_offset(fd, high); high *= 2)
low = high;
while (low < high - 1) {
const int mid = (low + high) / 2;
if (valid_offset(fd, mid))
low = mid;
else
high = mid;
}
valid_offset(fd, 0);
return (low + 1);
}
static int get_size(const char *file)
{
int fd;
long size;
fd = xopen(file, O_RDWR);
if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
close(fd);
return (size * 512);
}
size = count_blocks(fd);
close(fd);
return size;
}
static void write_tables(void)
{
/* Mark the superblock valid. */
SB.s_state |= MINIX_VALID_FS;
SB.s_state &= ~MINIX_ERROR_FS;
msg_eol = "seek to 0 failed";
xlseek(dev_fd, 0, SEEK_SET);
msg_eol = "cannot clear boot sector";
xwrite(dev_fd, G.boot_block_buffer, 512);
msg_eol = "seek to BLOCK_SIZE failed";
xlseek(dev_fd, BLOCK_SIZE, SEEK_SET);
msg_eol = "cannot write superblock";
xwrite(dev_fd, G.superblock_buffer, BLOCK_SIZE);
msg_eol = "cannot write inode map";
xwrite(dev_fd, G.inode_map, SB_IMAPS * BLOCK_SIZE);
msg_eol = "cannot write zone map";
xwrite(dev_fd, G.zone_map, SB_ZMAPS * BLOCK_SIZE);
msg_eol = "cannot write inodes";
xwrite(dev_fd, G.inode_buffer, INODE_BUFFER_SIZE);
msg_eol = "\n";
}
static void write_block(int blk, char *buffer)
{
xlseek(dev_fd, blk * BLOCK_SIZE, SEEK_SET);
xwrite(dev_fd, buffer, BLOCK_SIZE);
}
static int get_free_block(void)
{
int blk;
if (G.used_good_blocks + 1 >= MAX_GOOD_BLOCKS)
bb_error_msg_and_die("too many bad blocks");
if (G.used_good_blocks)
blk = G.good_blocks_table[G.used_good_blocks - 1] + 1;
else
blk = SB_FIRSTZONE;
while (blk < SB_ZONES && zone_in_use(blk))
blk++;
if (blk >= SB_ZONES)
bb_error_msg_and_die("not enough good blocks");
G.good_blocks_table[G.used_good_blocks] = blk;
G.used_good_blocks++;
return blk;
}
static void mark_good_blocks(void)
{
int blk;
for (blk = 0; blk < G.used_good_blocks; blk++)
mark_zone(G.good_blocks_table[blk]);
}
static int next(int zone)
{
if (!zone)
zone = SB_FIRSTZONE - 1;
while (++zone < SB_ZONES)
if (zone_in_use(zone))
return zone;
return 0;
}
static void make_bad_inode(void)
{
struct minix1_inode *inode = &INODE_BUF1[MINIX_BAD_INO];
int i, j, zone;
int ind = 0, dind = 0;
/* moved to globals to reduce stack usage
unsigned short ind_block[BLOCK_SIZE >> 1];
unsigned short dind_block[BLOCK_SIZE >> 1];
*/
#define ind_block (G.ind_block1)
#define dind_block (G.dind_block1)
#define NEXT_BAD (zone = next(zone))
if (!G.badblocks)
return;
mark_inode(MINIX_BAD_INO);
inode->i_nlinks = 1;
/* BTW, setting this makes all images different */
/* it's harder to check for bugs then - diff isn't helpful :(... */
inode->i_time = CUR_TIME;
inode->i_mode = S_IFREG + 0000;
inode->i_size = G.badblocks * BLOCK_SIZE;
zone = next(0);
for (i = 0; i < 7; i++) {
inode->i_zone[i] = zone;
if (!NEXT_BAD)
goto end_bad;
}
inode->i_zone[7] = ind = get_free_block();
memset(ind_block, 0, BLOCK_SIZE);
for (i = 0; i < 512; i++) {
ind_block[i] = zone;
if (!NEXT_BAD)
goto end_bad;
}
inode->i_zone[8] = dind = get_free_block();
memset(dind_block, 0, BLOCK_SIZE);
for (i = 0; i < 512; i++) {
write_block(ind, (char *) ind_block);
dind_block[i] = ind = get_free_block();
memset(ind_block, 0, BLOCK_SIZE);
for (j = 0; j < 512; j++) {
ind_block[j] = zone;
if (!NEXT_BAD)
goto end_bad;
}
}
bb_error_msg_and_die("too many bad blocks");
end_bad:
if (ind)
write_block(ind, (char *) ind_block);
if (dind)
write_block(dind, (char *) dind_block);
#undef ind_block
#undef dind_block
}
#if ENABLE_FEATURE_MINIX2
static void make_bad_inode2(void)
{
struct minix2_inode *inode = &INODE_BUF2[MINIX_BAD_INO];
int i, j, zone;
int ind = 0, dind = 0;
/* moved to globals to reduce stack usage
unsigned long ind_block[BLOCK_SIZE >> 2];
unsigned long dind_block[BLOCK_SIZE >> 2];
*/
#define ind_block (G.ind_block2)
#define dind_block (G.dind_block2)
if (!G.badblocks)
return;
mark_inode(MINIX_BAD_INO);
inode->i_nlinks = 1;
inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME;
inode->i_mode = S_IFREG + 0000;
inode->i_size = G.badblocks * BLOCK_SIZE;
zone = next(0);
for (i = 0; i < 7; i++) {
inode->i_zone[i] = zone;
if (!NEXT_BAD)
goto end_bad;
}
inode->i_zone[7] = ind = get_free_block();
memset(ind_block, 0, BLOCK_SIZE);
for (i = 0; i < 256; i++) {
ind_block[i] = zone;
if (!NEXT_BAD)
goto end_bad;
}
inode->i_zone[8] = dind = get_free_block();
memset(dind_block, 0, BLOCK_SIZE);
for (i = 0; i < 256; i++) {
write_block(ind, (char *) ind_block);
dind_block[i] = ind = get_free_block();
memset(ind_block, 0, BLOCK_SIZE);
for (j = 0; j < 256; j++) {
ind_block[j] = zone;
if (!NEXT_BAD)
goto end_bad;
}
}
/* Could make triple indirect block here */
bb_error_msg_and_die("too many bad blocks");
end_bad:
if (ind)
write_block(ind, (char *) ind_block);
if (dind)
write_block(dind, (char *) dind_block);
#undef ind_block
#undef dind_block
}
#else
void make_bad_inode2(void);
#endif
static void make_root_inode(void)
{
struct minix1_inode *inode = &INODE_BUF1[MINIX_ROOT_INO];
mark_inode(MINIX_ROOT_INO);
inode->i_zone[0] = get_free_block();
inode->i_nlinks = 2;
inode->i_time = CUR_TIME;
if (G.badblocks)
inode->i_size = 3 * G.dirsize;
else {
G.root_block[2 * G.dirsize] = '\0';
G.root_block[2 * G.dirsize + 1] = '\0';
inode->i_size = 2 * G.dirsize;
}
inode->i_mode = S_IFDIR + 0755;
inode->i_uid = GETUID;
if (inode->i_uid)
inode->i_gid = GETGID;
write_block(inode->i_zone[0], G.root_block);
}
#if ENABLE_FEATURE_MINIX2
static void make_root_inode2(void)
{
struct minix2_inode *inode = &INODE_BUF2[MINIX_ROOT_INO];
mark_inode(MINIX_ROOT_INO);
inode->i_zone[0] = get_free_block();
inode->i_nlinks = 2;
inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME;
if (G.badblocks)
inode->i_size = 3 * G.dirsize;
else {
G.root_block[2 * G.dirsize] = '\0';
G.root_block[2 * G.dirsize + 1] = '\0';
inode->i_size = 2 * G.dirsize;
}
inode->i_mode = S_IFDIR + 0755;
inode->i_uid = GETUID;
if (inode->i_uid)
inode->i_gid = GETGID;
write_block(inode->i_zone[0], G.root_block);
}
#else
void make_root_inode2(void);
#endif
/*
* Perform a test of a block; return the number of
* blocks readable.
*/
static size_t do_check(char *buffer, size_t try, unsigned current_block)
{
ssize_t got;
/* Seek to the correct loc. */
msg_eol = "seek failed during testing of blocks";
xlseek(dev_fd, current_block * BLOCK_SIZE, SEEK_SET);
msg_eol = "\n";
/* Try the read */
got = read(dev_fd, buffer, try * BLOCK_SIZE);
if (got < 0)
got = 0;
try = ((size_t)got) / BLOCK_SIZE;
if (got & (BLOCK_SIZE - 1))
fprintf(stderr, "Short read at block %u\n", (unsigned)(current_block + try));
return try;
}
static void alarm_intr(int alnum UNUSED_PARAM)
{
if (G.currently_testing >= SB_ZONES)
return;
signal(SIGALRM, alarm_intr);
alarm(5);
if (!G.currently_testing)
return;
printf("%d ...", G.currently_testing);
fflush(stdout);
}
static void check_blocks(void)
{
size_t try, got;
G.currently_testing = 0;
signal(SIGALRM, alarm_intr);
alarm(5);
while (G.currently_testing < SB_ZONES) {
msg_eol = "seek failed in check_blocks";
xlseek(dev_fd, G.currently_testing * BLOCK_SIZE, SEEK_SET);
msg_eol = "\n";
try = TEST_BUFFER_BLOCKS;
if (G.currently_testing + try > SB_ZONES)
try = SB_ZONES - G.currently_testing;
got = do_check(G.check_blocks_buffer, try, G.currently_testing);
G.currently_testing += got;
if (got == try)
continue;
if (G.currently_testing < SB_FIRSTZONE)
bb_error_msg_and_die("bad blocks before data-area: cannot make fs");
mark_zone(G.currently_testing);
G.badblocks++;
G.currently_testing++;
}
alarm(0);
printf("%d bad block(s)\n", G.badblocks);
}
static void get_list_blocks(char *filename)
{
FILE *listfile;
unsigned long blockno;
listfile = xfopen_for_read(filename);
while (!feof(listfile)) {
fscanf(listfile, "%ld\n", &blockno);
mark_zone(blockno);
G.badblocks++;
}
printf("%d bad block(s)\n", G.badblocks);
}
static void setup_tables(void)
{
unsigned long inodes;
unsigned norm_firstzone;
unsigned sb_zmaps;
unsigned i;
/* memset(G.superblock_buffer, 0, BLOCK_SIZE); */
/* memset(G.boot_block_buffer, 0, 512); */
SB_MAGIC = G.magic;
SB_ZONE_SIZE = 0;
SB_MAXSIZE = version2 ? 0x7fffffff : (7 + 512 + 512 * 512) * 1024;
if (version2)
SB.s_zones = G.total_blocks;
else
SB.s_nzones = G.total_blocks;
/* some magic nrs: 1 inode / 3 blocks */
if (G.req_nr_inodes == 0)
inodes = G.total_blocks / 3;
else
inodes = G.req_nr_inodes;
/* Round up inode count to fill block size */
if (version2)
inodes = (inodes + MINIX2_INODES_PER_BLOCK - 1) &
~(MINIX2_INODES_PER_BLOCK - 1);
else
inodes = (inodes + MINIX1_INODES_PER_BLOCK - 1) &
~(MINIX1_INODES_PER_BLOCK - 1);
if (inodes > 65535)
inodes = 65535;
SB_INODES = inodes;
SB_IMAPS = div_roundup(SB_INODES + 1, BITS_PER_BLOCK);
/* Real bad hack but overwise mkfs.minix can be thrown
* in infinite loop...
* try:
* dd if=/dev/zero of=test.fs count=10 bs=1024
* mkfs.minix -i 200 test.fs
*/
/* This code is not insane: NORM_FIRSTZONE is not a constant,
* it is calculated from SB_INODES, SB_IMAPS and SB_ZMAPS */
i = 999;
SB_ZMAPS = 0;
do {
norm_firstzone = NORM_FIRSTZONE;
sb_zmaps = div_roundup(G.total_blocks - norm_firstzone + 1, BITS_PER_BLOCK);
if (SB_ZMAPS == sb_zmaps) goto got_it;
SB_ZMAPS = sb_zmaps;
/* new SB_ZMAPS, need to recalc NORM_FIRSTZONE */
} while (--i);
bb_error_msg_and_die("incompatible size/inode count, try different -i N");
got_it:
SB_FIRSTZONE = norm_firstzone;
G.inode_map = xmalloc(SB_IMAPS * BLOCK_SIZE);
G.zone_map = xmalloc(SB_ZMAPS * BLOCK_SIZE);
memset(G.inode_map, 0xff, SB_IMAPS * BLOCK_SIZE);
memset(G.zone_map, 0xff, SB_ZMAPS * BLOCK_SIZE);
for (i = SB_FIRSTZONE; i < SB_ZONES; i++)
unmark_zone(i);
for (i = MINIX_ROOT_INO; i <= SB_INODES; i++)
unmark_inode(i);
G.inode_buffer = xzalloc(INODE_BUFFER_SIZE);
printf("%ld inodes\n", (long)SB_INODES);
printf("%ld blocks\n", (long)SB_ZONES);
printf("Firstdatazone=%ld (%ld)\n", (long)SB_FIRSTZONE, (long)norm_firstzone);
printf("Zonesize=%d\n", BLOCK_SIZE << SB_ZONE_SIZE);
printf("Maxsize=%ld\n", (long)SB_MAXSIZE);
}
int mkfs_minix_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mkfs_minix_main(int argc UNUSED_PARAM, char **argv)
{
struct mntent *mp;
unsigned opt;
char *tmp;
struct stat statbuf;
char *str_i;
char *listfile = NULL;
INIT_G();
/* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */
G.namelen = 30;
G.dirsize = 32;
G.magic = MINIX1_SUPER_MAGIC2;
if (INODE_SIZE1 * MINIX1_INODES_PER_BLOCK != BLOCK_SIZE)
bb_error_msg_and_die("bad inode size");
#if ENABLE_FEATURE_MINIX2
if (INODE_SIZE2 * MINIX2_INODES_PER_BLOCK != BLOCK_SIZE)
bb_error_msg_and_die("bad inode size");
#endif
opt_complementary = "n+"; /* -n N */
opt = getopt32(argv, "ci:l:n:v", &str_i, &listfile, &G.namelen);
argv += optind;
//if (opt & 1) -c
if (opt & 2) G.req_nr_inodes = xatoul(str_i); // -i
//if (opt & 4) -l
if (opt & 8) { // -n
if (G.namelen == 14) G.magic = MINIX1_SUPER_MAGIC;
else if (G.namelen == 30) G.magic = MINIX1_SUPER_MAGIC2;
else bb_show_usage();
G.dirsize = G.namelen + 2;
}
if (opt & 0x10) { // -v
#if ENABLE_FEATURE_MINIX2
version2 = 1;
#else
bb_error_msg_and_die("not compiled with minix v2 support");
#endif
}
G.device_name = *argv++;
if (!G.device_name)
bb_show_usage();
if (*argv)
G.total_blocks = xatou32(*argv);
else
G.total_blocks = get_size(G.device_name) / 1024;
if (G.total_blocks < 10)
bb_error_msg_and_die("must have at least 10 blocks");
if (version2) {
G.magic = MINIX2_SUPER_MAGIC2;
if (G.namelen == 14)
G.magic = MINIX2_SUPER_MAGIC;
} else if (G.total_blocks > 65535)
G.total_blocks = 65535;
/* Check if it is mounted */
mp = find_mount_point(G.device_name, NULL);
if (mp && strcmp(G.device_name, mp->mnt_fsname) == 0)
bb_error_msg_and_die("%s is mounted on %s; "
"refusing to make a filesystem",
G.device_name, mp->mnt_dir);
xmove_fd(xopen(G.device_name, O_RDWR), dev_fd);
if (fstat(dev_fd, &statbuf) < 0)
bb_error_msg_and_die("cannot stat %s", G.device_name);
if (!S_ISBLK(statbuf.st_mode))
opt &= ~1; // clear -c (check)
/* I don't know why someone has special code to prevent mkfs.minix
* on IDE devices. Why IDE but not SCSI, etc?... */
#if 0
else if (statbuf.st_rdev == 0x0300 || statbuf.st_rdev == 0x0340)
/* what is this? */
bb_error_msg_and_die("will not try "
"to make filesystem on '%s'", G.device_name);
#endif
tmp = G.root_block;
*(short *) tmp = 1;
strcpy(tmp + 2, ".");
tmp += G.dirsize;
*(short *) tmp = 1;
strcpy(tmp + 2, "..");
tmp += G.dirsize;
*(short *) tmp = 2;
strcpy(tmp + 2, ".badblocks");
setup_tables();
if (opt & 1) // -c ?
check_blocks();
else if (listfile)
get_list_blocks(listfile);
if (version2) {
make_root_inode2();
make_bad_inode2();
} else {
make_root_inode();
make_bad_inode();
}
mark_good_blocks();
write_tables();
return 0;
}