busybox/util-linux/mkfs_minix.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 "busybox.h"
#include <mntent.h>

#include "minix.h"

#define DEBUG 0

/* If debugging, store the very same times/uids/gids for image consistency */
#if DEBUG
# define CUR_TIME 0
# define GETUID 0
# define GETGID 0
#else
# 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
static int version2;
#else
enum { version2 = 0 };
#endif

static char *device_name;
static int dev_fd = -1;
static uint32_t total_blocks;
static int badblocks;
/* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */
static int namelen = 30;
static int dirsize = 32;
static int magic = MINIX1_SUPER_MAGIC2;

static char root_block[BLOCK_SIZE];
static char super_block_buffer[BLOCK_SIZE];
static char boot_block_buffer[512];
static char *inode_buffer;

static char *inode_map;
static char *zone_map;

static int used_good_blocks;
static unsigned short good_blocks_table[MAX_GOOD_BLOCKS];
static unsigned long req_nr_inodes;

static ATTRIBUTE_ALWAYS_INLINE unsigned div_roundup(unsigned size, unsigned n)
{
	return (size + n-1) / n;
}

#define INODE_BUF1              (((struct minix1_inode*)inode_buffer) - 1)
#define INODE_BUF2              (((struct minix2_inode*)inode_buffer) - 1)

#define SB                      (*(struct minix_super_block*)super_block_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)

static int bit(const char* a, unsigned i)
{
	  return a[i >> 3] & (1<<(i & 7));
}

/* Note: do not assume 0/1, it is 0/nonzero */
#define inode_in_use(x) bit(inode_map,(x))
#define zone_in_use(x)  bit(zone_map,(x)-SB_FIRSTZONE+1)

#define mark_inode(x)   setbit(inode_map,(x))
#define unmark_inode(x) clrbit(inode_map,(x))
#define mark_zone(x)    setbit(zone_map,(x)-SB_FIRSTZONE+1)
#define unmark_zone(x)  clrbit(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 super block 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, 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, super_block_buffer, BLOCK_SIZE);

	msg_eol = "cannot write inode map";
	xwrite(dev_fd, inode_map, SB_IMAPS * BLOCK_SIZE);

	msg_eol = "cannot write zone map";
	xwrite(dev_fd, zone_map, SB_ZMAPS * BLOCK_SIZE);

	msg_eol = "cannot write inodes";
	xwrite(dev_fd, 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 (used_good_blocks + 1 >= MAX_GOOD_BLOCKS)
		bb_error_msg_and_die("too many bad blocks");
	if (used_good_blocks)
		blk = good_blocks_table[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");
	good_blocks_table[used_good_blocks] = blk;
	used_good_blocks++;
	return blk;
}

static void mark_good_blocks(void)
{
	int blk;

	for (blk = 0; blk < used_good_blocks; blk++)
		mark_zone(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;
	unsigned short ind_block[BLOCK_SIZE >> 1];
	unsigned short dind_block[BLOCK_SIZE >> 1];

#define NEXT_BAD (zone = next(zone))

	if (!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 = 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);
}

#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;
	unsigned long ind_block[BLOCK_SIZE >> 2];
	unsigned long dind_block[BLOCK_SIZE >> 2];

	if (!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 = 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);
}
#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 (badblocks)
		inode->i_size = 3 * dirsize;
	else {
		root_block[2 * dirsize] = '\0';
		root_block[2 * dirsize + 1] = '\0';
		inode->i_size = 2 * 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], 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 (badblocks)
		inode->i_size = 3 * dirsize;
	else {
		root_block[2 * dirsize] = '\0';
		root_block[2 * dirsize + 1] = '\0';
		inode->i_size = 2 * 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], root_block);
}
#else
void make_root_inode2(void);
#endif

static void setup_tables(void)
{
	unsigned long inodes;
	unsigned norm_firstzone;
	unsigned sb_zmaps;
	unsigned i;

	memset(super_block_buffer, 0, BLOCK_SIZE);
	memset(boot_block_buffer, 0, 512);
	SB_MAGIC = magic;
	SB_ZONE_SIZE = 0;
	SB_MAXSIZE = version2 ? 0x7fffffff : (7 + 512 + 512 * 512) * 1024;
	if (version2)
		SB.s_zones = total_blocks;
	else
		SB.s_nzones = total_blocks;

	/* some magic nrs: 1 inode / 3 blocks */
	if (req_nr_inodes == 0)
		inodes = total_blocks / 3;
	else
		inodes = 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(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;
	inode_map = xmalloc(SB_IMAPS * BLOCK_SIZE);
	zone_map = xmalloc(SB_ZMAPS * BLOCK_SIZE);
	memset(inode_map, 0xff, SB_IMAPS * BLOCK_SIZE);
	memset(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);
	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);
}

/*
 * Perform a test of a block; return the number of
 * blocks readable/writable.
 */
static long do_check(char *buffer, int try, unsigned current_block)
{
	long 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;
	if (got & (BLOCK_SIZE - 1)) {
		printf("Weird values in do_check: probably bugs\n");
	}
	got /= BLOCK_SIZE;
	return got;
}

static unsigned currently_testing;

static void alarm_intr(int alnum)
{
	if (currently_testing >= SB_ZONES)
		return;
	signal(SIGALRM, alarm_intr);
	alarm(5);
	if (!currently_testing)
		return;
	printf("%d ...", currently_testing);
	fflush(stdout);
}

static void check_blocks(void)
{
	int try, got;
	/* buffer[] was the biggest static in entire bbox */
	char *buffer = xmalloc(BLOCK_SIZE * TEST_BUFFER_BLOCKS);

	currently_testing = 0;
	signal(SIGALRM, alarm_intr);
	alarm(5);
	while (currently_testing < SB_ZONES) {
		msg_eol = "seek failed in check_blocks";
		xlseek(dev_fd, currently_testing * BLOCK_SIZE, SEEK_SET);
		msg_eol = "\n";
		try = TEST_BUFFER_BLOCKS;
		if (currently_testing + try > SB_ZONES)
			try = SB_ZONES - currently_testing;
		got = do_check(buffer, try, currently_testing);
		currently_testing += got;
		if (got == try)
			continue;
		if (currently_testing < SB_FIRSTZONE)
			bb_error_msg_and_die("bad blocks before data-area: cannot make fs");
		mark_zone(currently_testing);
		badblocks++;
		currently_testing++;
	}
	free(buffer);
	printf("%d bad block(s)\n", badblocks);
}

static void get_list_blocks(char *filename)
{
	FILE *listfile;
	unsigned long blockno;

	listfile = xfopen(filename, "r");
	while (!feof(listfile)) {
		fscanf(listfile, "%ld\n", &blockno);
		mark_zone(blockno);
		badblocks++;
	}
	printf("%d bad block(s)\n", badblocks);
}

int mkfs_minix_main(int argc, char **argv)
{
	struct mntent *mp;
	unsigned opt;
	char *tmp;
	struct stat statbuf;
	char *str_i, *str_n;
	char *listfile = NULL;

	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 = getopt32(argc, argv, "ci:l:n:v", &str_i, &listfile, &str_n);
	argv += optind;
	//if (opt & 1) -c
	if (opt & 2) req_nr_inodes = xatoul(str_i); // -i
	//if (opt & 4) -l
	if (opt & 8) { // -n
		namelen = xatoi_u(str_n);
		if (namelen == 14) magic = MINIX1_SUPER_MAGIC;
		else if (namelen == 30) magic = MINIX1_SUPER_MAGIC2;
		else bb_show_usage();
		dirsize = namelen + 2;
	}
	if (opt & 0x10) { // -v
#if ENABLE_FEATURE_MINIX2
		version2 = 1;
#else
		bb_error_msg_and_die("%s: not compiled with minix v2 support",
			device_name);
#endif
	}

	device_name = *argv++;
	if (!device_name)
		bb_show_usage();
	if (*argv)
		total_blocks = xatou32(*argv);
	else
		total_blocks = get_size(device_name) / 1024;

	if (total_blocks < 10)
		bb_error_msg_and_die("must have at least 10 blocks");

	if (version2) {
		magic = MINIX2_SUPER_MAGIC2;
		if (namelen == 14)
			magic = MINIX2_SUPER_MAGIC;
	} else if (total_blocks > 65535)
		total_blocks = 65535;

	/* Check if it is mounted */
	mp = find_mount_point(device_name, NULL);
	if (mp && strcmp(device_name, mp->mnt_fsname) == 0)
		bb_error_msg_and_die("%s is mounted on %s; "
				"refusing to make a filesystem",
				device_name, mp->mnt_dir);

	dev_fd = xopen(device_name, O_RDWR);
	if (fstat(dev_fd, &statbuf) < 0)
		bb_error_msg_and_die("cannot stat %s", 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'", device_name);
#endif

	tmp = root_block;
	*(short *) tmp = 1;
	strcpy(tmp + 2, ".");
	tmp += dirsize;
	*(short *) tmp = 1;
	strcpy(tmp + 2, "..");
	tmp += 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;
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* mkfs.c - make a linux (minix) file-system.
4	*
5	* (C) 1991 Linus Torvalds. This file may be redistributed as per
6	* the Linux copyright.
7	*/
8
9	/*
10	* DD.MM.YY
11	*
12	* 24.11.91 - Time began. Used the fsck sources to get started.
13	*
14	* 25.11.91 - Corrected some bugs. Added support for ".badblocks"
15	* The algorithm for ".badblocks" is a bit weird, but
16	* it should work. Oh, well.
17	*
18	* 25.01.92 - Added the -l option for getting the list of bad blocks
19	* out of a named file. (Dave Rivers, rivers@ponds.uucp)
20	*
21	* 28.02.92 - Added %-information when using -c.
22	*
23	* 28.02.93 - Added support for other namelengths than the original
24	* 14 characters so that I can test the new kernel routines..
25	*
26	* 09.10.93 - Make exit status conform to that required by fsutil
27	* (Rik Faith, faith@cs.unc.edu)
28	*
29	* 31.10.93 - Added inode request feature, for backup floppies: use
30	* 32 inodes, for a news partition use more.
31	* (Scott Heavner, sdh@po.cwru.edu)
32	*
33	* 03.01.94 - Added support for file system valid flag.
34	* (Dr. Wettstein, greg%wind.uucp@plains.nodak.edu)
35	*
36	* 30.10.94 - added support for v2 filesystem
37	* (Andreas Schwab, schwab@issan.informatik.uni-dortmund.de)
38	*
39	* 09.11.94 - Added test to prevent overwrite of mounted fs adapted
40	* from Theodore Ts'o's (tytso@athena.mit.edu) mke2fs
41	* program. (Daniel Quinlan, quinlan@yggdrasil.com)
42	*
43	* 03.20.95 - Clear first 512 bytes of filesystem to make certain that
44	* the filesystem is not misidentified as a MS-DOS FAT filesystem.
45	* (Daniel Quinlan, quinlan@yggdrasil.com)
46	*
47	* 02.07.96 - Added small patch from Russell King to make the program a
48	* good deal more portable (janl@math.uio.no)
49	*
50	* Usage: mkfs [-c \| -l filename ] [-v] [-nXX] [-iXX] device [size-in-blocks]
51	*
52	* -c for readability checking (SLOW!)
53	* -l for getting a list of bad blocks from a file.
54	* -n for namelength (currently the kernel only uses 14 or 30)
55	* -i for number of inodes
56	* -v for v2 filesystem
57	*
58	* The device may be a block device or a image of one, but this isn't
59	* enforced (but it's not much fun on a character device :-).
60	*
61	* Modified for BusyBox by Erik Andersen <andersen@debian.org> --
62	* removed getopt based parser and added a hand rolled one.
63	*/
64
65	#include "busybox.h"
66	#include <mntent.h>
67
68	#include "minix.h"
69
70	#define DEBUG 0
71
72	/* If debugging, store the very same times/uids/gids for image consistency */
73	#if DEBUG
74	# define CUR_TIME 0
75	# define GETUID 0
76	# define GETGID 0
77	#else
78	# define CUR_TIME time(NULL)
79	# define GETUID getuid()
80	# define GETGID getgid()
81	#endif
82
83	enum {
84	MAX_GOOD_BLOCKS = 512,
85	TEST_BUFFER_BLOCKS = 16,
86	};
87
88	#if ENABLE_FEATURE_MINIX2
89	static int version2;
90	#else
91	enum { version2 = 0 };
92	#endif
93
94	static char *device_name;
95	static int dev_fd = -1;
96	static uint32_t total_blocks;
97	static int badblocks;
98	/* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */
99	static int namelen = 30;
100	static int dirsize = 32;
101	static int magic = MINIX1_SUPER_MAGIC2;
102
103	static char root_block[BLOCK_SIZE];
104	static char super_block_buffer[BLOCK_SIZE];
105	static char boot_block_buffer[512];
106	static char *inode_buffer;
107
108	static char *inode_map;
109	static char *zone_map;
110
111	static int used_good_blocks;
112	static unsigned short good_blocks_table[MAX_GOOD_BLOCKS];
113	static unsigned long req_nr_inodes;
114
115	static ATTRIBUTE_ALWAYS_INLINE unsigned div_roundup(unsigned size, unsigned n)
116	{
117	return (size + n-1) / n;
118	}
119
120	#define INODE_BUF1 (((struct minix1_inode*)inode_buffer) - 1)
121	#define INODE_BUF2 (((struct minix2_inode*)inode_buffer) - 1)
122
123	#define SB ((struct minix_super_block)super_block_buffer)
124
125	#define SB_INODES (SB.s_ninodes)
126	#define SB_IMAPS (SB.s_imap_blocks)
127	#define SB_ZMAPS (SB.s_zmap_blocks)
128	#define SB_FIRSTZONE (SB.s_firstdatazone)
129	#define SB_ZONE_SIZE (SB.s_log_zone_size)
130	#define SB_MAXSIZE (SB.s_max_size)
131	#define SB_MAGIC (SB.s_magic)
132
133	#if !ENABLE_FEATURE_MINIX2
134	# define SB_ZONES (SB.s_nzones)
135	# define INODE_BLOCKS div_roundup(SB_INODES, MINIX1_INODES_PER_BLOCK)
136	#else
137	# define SB_ZONES (version2 ? SB.s_zones : SB.s_nzones)
138	# define INODE_BLOCKS div_roundup(SB_INODES, \
139	version2 ? MINIX2_INODES_PER_BLOCK : MINIX1_INODES_PER_BLOCK)
140	#endif
141
142	#define INODE_BUFFER_SIZE (INODE_BLOCKS * BLOCK_SIZE)
143	#define NORM_FIRSTZONE (2 + SB_IMAPS + SB_ZMAPS + INODE_BLOCKS)
144
145	static int bit(const char* a, unsigned i)
146	{
147	return a[i >> 3] & (1<<(i & 7));
148	}
149
150	/* Note: do not assume 0/1, it is 0/nonzero */
151	#define inode_in_use(x) bit(inode_map,(x))
152	#define zone_in_use(x) bit(zone_map,(x)-SB_FIRSTZONE+1)
153
154	#define mark_inode(x) setbit(inode_map,(x))
155	#define unmark_inode(x) clrbit(inode_map,(x))
156	#define mark_zone(x) setbit(zone_map,(x)-SB_FIRSTZONE+1)
157	#define unmark_zone(x) clrbit(zone_map,(x)-SB_FIRSTZONE+1)
158
159	#ifndef BLKGETSIZE
160	# define BLKGETSIZE _IO(0x12,96) /* return device size */
161	#endif
162
163
164	static long valid_offset(int fd, int offset)
165	{
166	char ch;
167
168	if (lseek(fd, offset, SEEK_SET) < 0)
169	return 0;
170	if (read(fd, &ch, 1) < 1)
171	return 0;
172	return 1;
173	}
174
175	static int count_blocks(int fd)
176	{
177	int high, low;
178
179	low = 0;
180	for (high = 1; valid_offset(fd, high); high *= 2)
181	low = high;
182
183	while (low < high - 1) {
184	const int mid = (low + high) / 2;
185
186	if (valid_offset(fd, mid))
187	low = mid;
188	else
189	high = mid;
190	}
191	valid_offset(fd, 0);
192	return (low + 1);
193	}
194
195	static int get_size(const char *file)
196	{
197	int fd;
198	long size;
199
200	fd = xopen(file, O_RDWR);
201	if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
202	close(fd);
203	return (size * 512);
204	}
205
206	size = count_blocks(fd);
207	close(fd);
208	return size;
209	}
210
211	static void write_tables(void)
212	{
213	/* Mark the super block valid. */
214	SB.s_state \|= MINIX_VALID_FS;
215	SB.s_state &= ~MINIX_ERROR_FS;
216
217	msg_eol = "seek to 0 failed";
218	xlseek(dev_fd, 0, SEEK_SET);
219
220	msg_eol = "cannot clear boot sector";
221	xwrite(dev_fd, boot_block_buffer, 512);
222
223	msg_eol = "seek to BLOCK_SIZE failed";
224	xlseek(dev_fd, BLOCK_SIZE, SEEK_SET);
225
226	msg_eol = "cannot write superblock";
227	xwrite(dev_fd, super_block_buffer, BLOCK_SIZE);
228
229	msg_eol = "cannot write inode map";
230	xwrite(dev_fd, inode_map, SB_IMAPS * BLOCK_SIZE);
231
232	msg_eol = "cannot write zone map";
233	xwrite(dev_fd, zone_map, SB_ZMAPS * BLOCK_SIZE);
234
235	msg_eol = "cannot write inodes";
236	xwrite(dev_fd, inode_buffer, INODE_BUFFER_SIZE);
237
238	msg_eol = "\n";
239	}
240
241	static void write_block(int blk, char *buffer)
242	{
243	xlseek(dev_fd, blk * BLOCK_SIZE, SEEK_SET);
244	xwrite(dev_fd, buffer, BLOCK_SIZE);
245	}
246
247	static int get_free_block(void)
248	{
249	int blk;
250
251	if (used_good_blocks + 1 >= MAX_GOOD_BLOCKS)
252	bb_error_msg_and_die("too many bad blocks");
253	if (used_good_blocks)
254	blk = good_blocks_table[used_good_blocks - 1] + 1;
255	else
256	blk = SB_FIRSTZONE;
257	while (blk < SB_ZONES && zone_in_use(blk))
258	blk++;
259	if (blk >= SB_ZONES)
260	bb_error_msg_and_die("not enough good blocks");
261	good_blocks_table[used_good_blocks] = blk;
262	used_good_blocks++;
263	return blk;
264	}
265
266	static void mark_good_blocks(void)
267	{
268	int blk;
269
270	for (blk = 0; blk < used_good_blocks; blk++)
271	mark_zone(good_blocks_table[blk]);
272	}
273
274	static int next(int zone)
275	{
276	if (!zone)
277	zone = SB_FIRSTZONE - 1;
278	while (++zone < SB_ZONES)
279	if (zone_in_use(zone))
280	return zone;
281	return 0;
282	}
283
284	static void make_bad_inode(void)
285	{
286	struct minix1_inode *inode = &INODE_BUF1[MINIX_BAD_INO];
287	int i, j, zone;
288	int ind = 0, dind = 0;
289	unsigned short ind_block[BLOCK_SIZE >> 1];
290	unsigned short dind_block[BLOCK_SIZE >> 1];
291
292	#define NEXT_BAD (zone = next(zone))
293
294	if (!badblocks)
295	return;
296	mark_inode(MINIX_BAD_INO);
297	inode->i_nlinks = 1;
298	/* BTW, setting this makes all images different */
299	/* it's harder to check for bugs then - diff isn't helpful :(... */
300	inode->i_time = CUR_TIME;
301	inode->i_mode = S_IFREG + 0000;
302	inode->i_size = badblocks * BLOCK_SIZE;
303	zone = next(0);
304	for (i = 0; i < 7; i++) {
305	inode->i_zone[i] = zone;
306	if (!NEXT_BAD)
307	goto end_bad;
308	}
309	inode->i_zone[7] = ind = get_free_block();
310	memset(ind_block, 0, BLOCK_SIZE);
311	for (i = 0; i < 512; i++) {
312	ind_block[i] = zone;
313	if (!NEXT_BAD)
314	goto end_bad;
315	}
316	inode->i_zone[8] = dind = get_free_block();
317	memset(dind_block, 0, BLOCK_SIZE);
318	for (i = 0; i < 512; i++) {
319	write_block(ind, (char *) ind_block);
320	dind_block[i] = ind = get_free_block();
321	memset(ind_block, 0, BLOCK_SIZE);
322	for (j = 0; j < 512; j++) {
323	ind_block[j] = zone;
324	if (!NEXT_BAD)
325	goto end_bad;
326	}
327	}
328	bb_error_msg_and_die("too many bad blocks");
329	end_bad:
330	if (ind)
331	write_block(ind, (char *) ind_block);
332	if (dind)
333	write_block(dind, (char *) dind_block);
334	}
335
336	#if ENABLE_FEATURE_MINIX2
337	static void make_bad_inode2(void)
338	{
339	struct minix2_inode *inode = &INODE_BUF2[MINIX_BAD_INO];
340	int i, j, zone;
341	int ind = 0, dind = 0;
342	unsigned long ind_block[BLOCK_SIZE >> 2];
343	unsigned long dind_block[BLOCK_SIZE >> 2];
344
345	if (!badblocks)
346	return;
347	mark_inode(MINIX_BAD_INO);
348	inode->i_nlinks = 1;
349	inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME;
350	inode->i_mode = S_IFREG + 0000;
351	inode->i_size = badblocks * BLOCK_SIZE;
352	zone = next(0);
353	for (i = 0; i < 7; i++) {
354	inode->i_zone[i] = zone;
355	if (!NEXT_BAD)
356	goto end_bad;
357	}
358	inode->i_zone[7] = ind = get_free_block();
359	memset(ind_block, 0, BLOCK_SIZE);
360	for (i = 0; i < 256; i++) {
361	ind_block[i] = zone;
362	if (!NEXT_BAD)
363	goto end_bad;
364	}
365	inode->i_zone[8] = dind = get_free_block();
366	memset(dind_block, 0, BLOCK_SIZE);
367	for (i = 0; i < 256; i++) {
368	write_block(ind, (char *) ind_block);
369	dind_block[i] = ind = get_free_block();
370	memset(ind_block, 0, BLOCK_SIZE);
371	for (j = 0; j < 256; j++) {
372	ind_block[j] = zone;
373	if (!NEXT_BAD)
374	goto end_bad;
375	}
376	}
377	/* Could make triple indirect block here */
378	bb_error_msg_and_die("too many bad blocks");
379	end_bad:
380	if (ind)
381	write_block(ind, (char *) ind_block);
382	if (dind)
383	write_block(dind, (char *) dind_block);
384	}
385	#else
386	void make_bad_inode2(void);
387	#endif
388
389	static void make_root_inode(void)
390	{
391	struct minix1_inode *inode = &INODE_BUF1[MINIX_ROOT_INO];
392
393	mark_inode(MINIX_ROOT_INO);
394	inode->i_zone[0] = get_free_block();
395	inode->i_nlinks = 2;
396	inode->i_time = CUR_TIME;
397	if (badblocks)
398	inode->i_size = 3 * dirsize;
399	else {
400	root_block[2 * dirsize] = '\0';
401	root_block[2 * dirsize + 1] = '\0';
402	inode->i_size = 2 * dirsize;
403	}
404	inode->i_mode = S_IFDIR + 0755;
405	inode->i_uid = GETUID;
406	if (inode->i_uid)
407	inode->i_gid = GETGID;
408	write_block(inode->i_zone[0], root_block);
409	}
410
411	#if ENABLE_FEATURE_MINIX2
412	static void make_root_inode2(void)
413	{
414	struct minix2_inode *inode = &INODE_BUF2[MINIX_ROOT_INO];
415
416	mark_inode(MINIX_ROOT_INO);
417	inode->i_zone[0] = get_free_block();
418	inode->i_nlinks = 2;
419	inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME;
420	if (badblocks)
421	inode->i_size = 3 * dirsize;
422	else {
423	root_block[2 * dirsize] = '\0';
424	root_block[2 * dirsize + 1] = '\0';
425	inode->i_size = 2 * dirsize;
426	}
427	inode->i_mode = S_IFDIR + 0755;
428	inode->i_uid = GETUID;
429	if (inode->i_uid)
430	inode->i_gid = GETGID;
431	write_block(inode->i_zone[0], root_block);
432	}
433	#else
434	void make_root_inode2(void);
435	#endif
436
437	static void setup_tables(void)
438	{
439	unsigned long inodes;
440	unsigned norm_firstzone;
441	unsigned sb_zmaps;
442	unsigned i;
443
444	memset(super_block_buffer, 0, BLOCK_SIZE);
445	memset(boot_block_buffer, 0, 512);
446	SB_MAGIC = magic;
447	SB_ZONE_SIZE = 0;
448	SB_MAXSIZE = version2 ? 0x7fffffff : (7 + 512 + 512 * 512) * 1024;
449	if (version2)
450	SB.s_zones = total_blocks;
451	else
452	SB.s_nzones = total_blocks;
453
454	/* some magic nrs: 1 inode / 3 blocks */
455	if (req_nr_inodes == 0)
456	inodes = total_blocks / 3;
457	else
458	inodes = req_nr_inodes;
459	/* Round up inode count to fill block size */
460	if (version2)
461	inodes = (inodes + MINIX2_INODES_PER_BLOCK - 1) &
462	~(MINIX2_INODES_PER_BLOCK - 1);
463	else
464	inodes = (inodes + MINIX1_INODES_PER_BLOCK - 1) &
465	~(MINIX1_INODES_PER_BLOCK - 1);
466	if (inodes > 65535)
467	inodes = 65535;
468	SB_INODES = inodes;
469	SB_IMAPS = div_roundup(SB_INODES + 1, BITS_PER_BLOCK);
470
471	/* Real bad hack but overwise mkfs.minix can be thrown
472	* in infinite loop...
473	* try:
474	* dd if=/dev/zero of=test.fs count=10 bs=1024
475	* mkfs.minix -i 200 test.fs
476	*/
477	/* This code is not insane: NORM_FIRSTZONE is not a constant,
478	* it is calculated from SB_INODES, SB_IMAPS and SB_ZMAPS */
479	i = 999;
480	SB_ZMAPS = 0;
481	do {
482	norm_firstzone = NORM_FIRSTZONE;
483	sb_zmaps = div_roundup(total_blocks - norm_firstzone + 1, BITS_PER_BLOCK);
484	if (SB_ZMAPS == sb_zmaps) goto got_it;
485	SB_ZMAPS = sb_zmaps;
486	/* new SB_ZMAPS, need to recalc NORM_FIRSTZONE */
487	} while (--i);
488	bb_error_msg_and_die("incompatible size/inode count, try different -i N");
489	got_it:
490
491	SB_FIRSTZONE = norm_firstzone;
492	inode_map = xmalloc(SB_IMAPS * BLOCK_SIZE);
493	zone_map = xmalloc(SB_ZMAPS * BLOCK_SIZE);
494	memset(inode_map, 0xff, SB_IMAPS * BLOCK_SIZE);
495	memset(zone_map, 0xff, SB_ZMAPS * BLOCK_SIZE);
496	for (i = SB_FIRSTZONE; i < SB_ZONES; i++)
497	unmark_zone(i);
498	for (i = MINIX_ROOT_INO; i <= SB_INODES; i++)
499	unmark_inode(i);
500	inode_buffer = xzalloc(INODE_BUFFER_SIZE);
501	printf("%ld inodes\n", (long)SB_INODES);
502	printf("%ld blocks\n", (long)SB_ZONES);
503	printf("Firstdatazone=%ld (%ld)\n", (long)SB_FIRSTZONE, (long)norm_firstzone);
504	printf("Zonesize=%d\n", BLOCK_SIZE << SB_ZONE_SIZE);
505	printf("Maxsize=%ld\n", (long)SB_MAXSIZE);
506	}
507
508	/*
509	* Perform a test of a block; return the number of
510	* blocks readable/writable.
511	*/
512	static long do_check(char *buffer, int try, unsigned current_block)
513	{
514	long got;
515
516	/* Seek to the correct loc. */
517	msg_eol = "seek failed during testing of blocks";
518	xlseek(dev_fd, current_block * BLOCK_SIZE, SEEK_SET);
519	msg_eol = "\n";
520
521	/* Try the read */
522	got = read(dev_fd, buffer, try * BLOCK_SIZE);
523	if (got < 0)
524	got = 0;
525	if (got & (BLOCK_SIZE - 1)) {
526	printf("Weird values in do_check: probably bugs\n");
527	}
528	got /= BLOCK_SIZE;
529	return got;
530	}
531
532	static unsigned currently_testing;
533
534	static void alarm_intr(int alnum)
535	{
536	if (currently_testing >= SB_ZONES)
537	return;
538	signal(SIGALRM, alarm_intr);
539	alarm(5);
540	if (!currently_testing)
541	return;
542	printf("%d ...", currently_testing);
543	fflush(stdout);
544	}
545
546	static void check_blocks(void)
547	{
548	int try, got;
549	/* buffer[] was the biggest static in entire bbox */
550	char buffer = xmalloc(BLOCK_SIZE TEST_BUFFER_BLOCKS);
551
552	currently_testing = 0;
553	signal(SIGALRM, alarm_intr);
554	alarm(5);
555	while (currently_testing < SB_ZONES) {
556	msg_eol = "seek failed in check_blocks";
557	xlseek(dev_fd, currently_testing * BLOCK_SIZE, SEEK_SET);
558	msg_eol = "\n";
559	try = TEST_BUFFER_BLOCKS;
560	if (currently_testing + try > SB_ZONES)
561	try = SB_ZONES - currently_testing;
562	got = do_check(buffer, try, currently_testing);
563	currently_testing += got;
564	if (got == try)
565	continue;
566	if (currently_testing < SB_FIRSTZONE)
567	bb_error_msg_and_die("bad blocks before data-area: cannot make fs");
568	mark_zone(currently_testing);
569	badblocks++;
570	currently_testing++;
571	}
572	free(buffer);
573	printf("%d bad block(s)\n", badblocks);
574	}
575
576	static void get_list_blocks(char *filename)
577	{
578	FILE *listfile;
579	unsigned long blockno;
580
581	listfile = xfopen(filename, "r");
582	while (!feof(listfile)) {
583	fscanf(listfile, "%ld\n", &blockno);
584	mark_zone(blockno);
585	badblocks++;
586	}
587	printf("%d bad block(s)\n", badblocks);
588	}
589
590	int mkfs_minix_main(int argc, char **argv)
591	{
592	struct mntent *mp;
593	unsigned opt;
594	char *tmp;
595	struct stat statbuf;
596	char str_i, str_n;
597	char *listfile = NULL;
598
599	if (INODE_SIZE1 * MINIX1_INODES_PER_BLOCK != BLOCK_SIZE)
600	bb_error_msg_and_die("bad inode size");
601	#if ENABLE_FEATURE_MINIX2
602	if (INODE_SIZE2 * MINIX2_INODES_PER_BLOCK != BLOCK_SIZE)
603	bb_error_msg_and_die("bad inode size");
604	#endif
605
606	opt = getopt32(argc, argv, "ci:l:n:v", &str_i, &listfile, &str_n);
607	argv += optind;
608	//if (opt & 1) -c
609	if (opt & 2) req_nr_inodes = xatoul(str_i); // -i
610	//if (opt & 4) -l
611	if (opt & 8) { // -n
612	namelen = xatoi_u(str_n);
613	if (namelen == 14) magic = MINIX1_SUPER_MAGIC;
614	else if (namelen == 30) magic = MINIX1_SUPER_MAGIC2;
615	else bb_show_usage();
616	dirsize = namelen + 2;
617	}
618	if (opt & 0x10) { // -v
619	#if ENABLE_FEATURE_MINIX2
620	version2 = 1;
621	#else
622	bb_error_msg_and_die("%s: not compiled with minix v2 support",
623	device_name);
624	#endif
625	}
626
627	device_name = *argv++;
628	if (!device_name)
629	bb_show_usage();
630	if (*argv)
631	total_blocks = xatou32(*argv);
632	else
633	total_blocks = get_size(device_name) / 1024;
634
635	if (total_blocks < 10)
636	bb_error_msg_and_die("must have at least 10 blocks");
637
638	if (version2) {
639	magic = MINIX2_SUPER_MAGIC2;
640	if (namelen == 14)
641	magic = MINIX2_SUPER_MAGIC;
642	} else if (total_blocks > 65535)
643	total_blocks = 65535;
644
645	/* Check if it is mounted */
646	mp = find_mount_point(device_name, NULL);
647	if (mp && strcmp(device_name, mp->mnt_fsname) == 0)
648	bb_error_msg_and_die("%s is mounted on %s; "
649	"refusing to make a filesystem",
650	device_name, mp->mnt_dir);
651
652	dev_fd = xopen(device_name, O_RDWR);
653	if (fstat(dev_fd, &statbuf) < 0)
654	bb_error_msg_and_die("cannot stat %s", device_name);
655	if (!S_ISBLK(statbuf.st_mode))
656	opt &= ~1; // clear -c (check)
657
658	/* I don't know why someone has special code to prevent mkfs.minix
659	* on IDE devices. Why IDE but not SCSI, etc?... */
660	#if 0
661	else if (statbuf.st_rdev == 0x0300 \|\| statbuf.st_rdev == 0x0340)
662	/* what is this? */
663	bb_error_msg_and_die("will not try "
664	"to make filesystem on '%s'", device_name);
665	#endif
666
667	tmp = root_block;
668	(short ) tmp = 1;
669	strcpy(tmp + 2, ".");
670	tmp += dirsize;
671	(short ) tmp = 1;
672	strcpy(tmp + 2, "..");
673	tmp += dirsize;
674	(short ) tmp = 2;
675	strcpy(tmp + 2, ".badblocks");
676
677	setup_tables();
678
679	if (opt & 1) // -c ?
680	check_blocks();
681	else if (listfile)
682	get_list_blocks(listfile);
683
684	if (version2) {
685	make_root_inode2();
686	make_bad_inode2();
687	} else {
688	make_root_inode();
689	make_bad_inode();
690	}
691
692	mark_good_blocks();
693	write_tables();
694	return 0;
695	}