mke2fs.c

busybox最新版的源码:学习和应用的好东东,多的不说了,大家看后再说吧

		blk = fs->group_desc[i].bg_inode_table;
		num = fs->inode_blocks_per_group;

		retval = zero_blocks(fs, blk, num, 0, &blk, &num);
		mke2fs_error_msg_and_die(retval,
			"write %d blocks in inode table starting at %d.",
			num, blk);
		if (sync_kludge) {
			if (sync_kludge == 1)
				sync();
			else if ((i % sync_kludge) == 0)
				sync();
		}
	}
	zero_blocks(0, 0, 0, 0, 0, 0);
	progress_close(&progress);
}

static void create_root_dir(ext2_filsys fs)
{
	errcode_t		retval;
	struct ext2_inode	inode;

	retval = ext2fs_mkdir(fs, EXT2_ROOT_INO, EXT2_ROOT_INO, 0);
	mke2fs_error_msg_and_die(retval, "create root dir");
	if (geteuid()) {
		retval = ext2fs_read_inode(fs, EXT2_ROOT_INO, &inode);
		mke2fs_error_msg_and_die(retval, "read root inode");
		inode.i_uid = getuid();
		if (inode.i_uid)
			inode.i_gid = getgid();
		retval = ext2fs_write_new_inode(fs, EXT2_ROOT_INO, &inode);
		mke2fs_error_msg_and_die(retval, "set root inode ownership");
	}
}

static void create_lost_and_found(ext2_filsys fs)
{
	errcode_t		retval;
	ext2_ino_t		ino;
	const char		*name = "lost+found";
	int			i = 1;
	char			*msg = "create";
	int			lpf_size = 0;

	fs->umask = 077;
	retval = ext2fs_mkdir(fs, EXT2_ROOT_INO, 0, name);
	if (retval) {
		goto CREATE_LOST_AND_FOUND_ERROR;
	}

	retval = ext2fs_lookup(fs, EXT2_ROOT_INO, name, strlen(name), 0, &ino);
	if (retval) {
		msg = "lookup";
		goto CREATE_LOST_AND_FOUND_ERROR;
	}

	for (; i < EXT2_NDIR_BLOCKS; i++) {
		if ((lpf_size += fs->blocksize) >= 16*1024)
			break;
		retval = ext2fs_expand_dir(fs, ino);
		msg = "expand";
CREATE_LOST_AND_FOUND_ERROR:
		mke2fs_error_msg_and_die(retval, "%s %s", msg, name);
	}
}

static void create_bad_block_inode(ext2_filsys fs, badblocks_list bb_list)
{
	errcode_t	retval;

	ext2fs_mark_inode_bitmap(fs->inode_map, EXT2_BAD_INO);
	fs->group_desc[0].bg_free_inodes_count--;
	fs->super->s_free_inodes_count--;
	retval = ext2fs_update_bb_inode(fs, bb_list);
	mke2fs_error_msg_and_die(retval, "set bad block inode");
}

static void reserve_inodes(ext2_filsys fs)
{
	ext2_ino_t	i;
	int		group;

	for (i = EXT2_ROOT_INO + 1; i < EXT2_FIRST_INODE(fs->super); i++) {
		ext2fs_mark_inode_bitmap(fs->inode_map, i);
		group = ext2fs_group_of_ino(fs, i);
		fs->group_desc[group].bg_free_inodes_count--;
		fs->super->s_free_inodes_count--;
	}
	ext2fs_mark_ib_dirty(fs);
}

#define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
#define BSD_MAGICDISK   (0x57455682UL)  /* The disk magic number reversed */
#define BSD_LABEL_OFFSET        64

static void zap_sector(ext2_filsys fs, int sect, int nsect)
{
	char *buf;
	char *fmt = "could not %s %d";
	int retval;
	unsigned int *magic;

	buf = xmalloc(512*nsect);

	if (sect == 0) {
		/* Check for a BSD disklabel, and don't erase it if so */
		retval = io_channel_read_blk(fs->io, 0, -512, buf);
		if (retval)
			mke2fs_warning_msg(retval, fmt, "read block", 0);
		else {
			magic = (unsigned int *) (buf + BSD_LABEL_OFFSET);
			if ((*magic == BSD_DISKMAGIC) ||
			    (*magic == BSD_MAGICDISK))
				return;
		}
	}

	memset(buf, 0, 512*nsect);
	io_channel_set_blksize(fs->io, 512);
	retval = io_channel_write_blk(fs->io, sect, -512*nsect, buf);
	io_channel_set_blksize(fs->io, fs->blocksize);
	free(buf);
	mke2fs_warning_msg(retval, fmt, "erase sector", sect);
}

static void create_journal_dev(ext2_filsys fs)
{
	struct progress_struct	progress;
	errcode_t		retval;
	char			*buf;
	char			*fmt = "%s journal superblock";
	blk_t			blk;
	int			count;

	retval = ext2fs_create_journal_superblock(fs,
				  fs->super->s_blocks_count, 0, &buf);
	mke2fs_error_msg_and_die(retval, fmt, "init");
	if (quiet)
		memset(&progress, 0, sizeof(progress));
	else
		progress_init(&progress, "Zeroing journal device: ",
			      fs->super->s_blocks_count);

	retval = zero_blocks(fs, 0, fs->super->s_blocks_count,
			     &progress, &blk, &count);
	mke2fs_error_msg_and_die(retval, "zero journal device (block %u, count %d)",
			blk, count);
	zero_blocks(0, 0, 0, 0, 0, 0);

	retval = io_channel_write_blk(fs->io,
				      fs->super->s_first_data_block+1,
				      1, buf);
	mke2fs_error_msg_and_die(retval, fmt, "write");
	progress_close(&progress);
}

static void show_stats(ext2_filsys fs)
{
	struct ext2_super_block *s = fs->super;
	char			*os;
	blk_t			group_block;
	dgrp_t			i;
	int			need, col_left;

	mke2fs_warning_msg((param.s_blocks_count != s->s_blocks_count),
		"%d blocks unused\n", param.s_blocks_count - s->s_blocks_count);
	os = e2p_os2string(fs->super->s_creator_os);
	printf(	"Filesystem label=%.*s\n"
			"OS type: %s\n"
			"Block size=%u (log=%u)\n"
			"Fragment size=%u (log=%u)\n"
			"%u inodes, %u blocks\n"
			"%u blocks (%2.2f%%) reserved for the super user\n"
			"First data block=%u\n",
			(int) sizeof(s->s_volume_name),
			s->s_volume_name,
			os,
			fs->blocksize, s->s_log_block_size,
			fs->fragsize, s->s_log_frag_size,
			s->s_inodes_count, s->s_blocks_count,
			s->s_r_blocks_count, 100.0 * s->s_r_blocks_count / s->s_blocks_count,
			s->s_first_data_block);
	free(os);
	if (s->s_reserved_gdt_blocks) {
		printf("Maximum filesystem blocks=%lu\n",
		       (s->s_reserved_gdt_blocks + fs->desc_blocks) *
		       (fs->blocksize / sizeof(struct ext2_group_desc)) *
		       s->s_blocks_per_group);
	}
	printf(	"%u block group%s\n"
			"%u blocks per group, %u fragments per group\n"
			"%u inodes per group\n",
			fs->group_desc_count, (fs->group_desc_count > 1) ? "s" : "",
			s->s_blocks_per_group, s->s_frags_per_group,
			s->s_inodes_per_group);
	if (fs->group_desc_count == 1) {
		puts("");
		return;
	}

	printf("Superblock backups stored on blocks: ");
	group_block = s->s_first_data_block;
	col_left = 0;
	for (i = 1; i < fs->group_desc_count; i++) {
		group_block += s->s_blocks_per_group;
		if (!ext2fs_bg_has_super(fs, i))
			continue;
		if (i != 1)
			printf(", ");
		need = int_log10(group_block) + 2;
		if (need > col_left) {
			printf("\n\t");
			col_left = 72;
		}
		col_left -= need;
		printf("%u", group_block);
	}
	puts("\n");
}

/*
 * Set the S_CREATOR_OS field.  Return true if OS is known,
 * otherwise, 0.
 */
static int set_os(struct ext2_super_block *sb, char *os)
{
	if (isdigit (*os)) {
		sb->s_creator_os = atoi(os);
		return 1;
	}

	if((sb->s_creator_os = e2p_string2os(os)) >= 0) {
		return 1;
	} else if (!strcasecmp("GNU", os)) {
		sb->s_creator_os = EXT2_OS_HURD;
		return 1;
	}
	return 0;
}

static void parse_extended_opts(struct ext2_super_block *sb_param,
				const char *opts)
{
	char	*buf, *token, *next, *p, *arg;
	int	r_usage = 0;

	buf = xstrdup(opts);
	for (token = buf; token && *token; token = next) {
		p = strchr(token, ',');
		next = 0;
		if (p) {
			*p = 0;
			next = p+1;
		}
		arg = strchr(token, '=');
		if (arg) {
			*arg = 0;
			arg++;
		}
		if (strcmp(token, "stride") == 0) {
			if (!arg) {
				r_usage++;
				continue;
			}
			fs_stride = strtoul(arg, &p, 0);
			if (*p || (fs_stride == 0)) {
				bb_error_msg("Invalid stride parameter: %s", arg);
				r_usage++;
				continue;
			}
		} else if (!strcmp(token, "resize")) {
			unsigned long resize, bpg, rsv_groups;
			unsigned long group_desc_count, desc_blocks;
			unsigned int gdpb, blocksize;
			int rsv_gdb;

			if (!arg) {
				r_usage++;
				continue;
			}

			resize = parse_num_blocks(arg,
						  sb_param->s_log_block_size);

			if (resize == 0) {
				bb_error_msg("Invalid resize parameter: %s", arg);
				r_usage++;
				continue;
			}
			if (resize <= sb_param->s_blocks_count) {
				bb_error_msg("The resize maximum must be greater "
						"than the filesystem size");
				r_usage++;
				continue;
			}

			blocksize = EXT2_BLOCK_SIZE(sb_param);
			bpg = sb_param->s_blocks_per_group;
			if (!bpg)
				bpg = blocksize * 8;
			gdpb = blocksize / sizeof(struct ext2_group_desc);
			group_desc_count = (sb_param->s_blocks_count +
					    bpg - 1) / bpg;
			desc_blocks = (group_desc_count +
				       gdpb - 1) / gdpb;
			rsv_groups = (resize + bpg - 1) / bpg;
			rsv_gdb = (rsv_groups + gdpb - 1) / gdpb -
				desc_blocks;
			if (rsv_gdb > EXT2_ADDR_PER_BLOCK(sb_param))
				rsv_gdb = EXT2_ADDR_PER_BLOCK(sb_param);

			if (rsv_gdb > 0) {
				sb_param->s_feature_compat |=
					EXT2_FEATURE_COMPAT_RESIZE_INODE;

				sb_param->s_reserved_gdt_blocks = rsv_gdb;
			}
		} else
			r_usage++;
	}
	if (r_usage) {
		bb_error_msg_and_die(
			"\nBad options specified.\n\n"
			"Extended options are separated by commas, "
			"and may take an argument which\n"
			"\tis set off by an equals ('=') sign.\n\n"
			"Valid extended options are:\n"
			"\tstride=<stride length in blocks>\n"
			"\tresize=<resize maximum size in blocks>\n");
	}
}

static __u32 ok_features[3] = {
	EXT3_FEATURE_COMPAT_HAS_JOURNAL |
		EXT2_FEATURE_COMPAT_RESIZE_INODE |
		EXT2_FEATURE_COMPAT_DIR_INDEX,  /* Compat */
	EXT2_FEATURE_INCOMPAT_FILETYPE|         /* Incompat */
		EXT3_FEATURE_INCOMPAT_JOURNAL_DEV|
		EXT2_FEATURE_INCOMPAT_META_BG,
	EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER     /* R/O compat */
};

static int PRS(int argc, char **argv)
{
	int		c;
	int		size;
	char *		tmp;
	int		blocksize = 0;
	int		inode_ratio = 0;
	int		inode_size = 0;
	int		reserved_ratio = 5;
	int		sector_size = 0;
	int		show_version_only = 0;
	ext2_ino_t	num_inodes = 0;
	errcode_t	retval;
	char *		extended_opts = 0;
	const char *	fs_type = 0;
	blk_t		dev_size;
	long		sysval;

	/* Update our PATH to include /sbin  */
	e2fs_set_sbin_path();

	tmp = getenv("MKE2FS_SYNC");
	if (tmp)
		sync_kludge = atoi(tmp);

	/* Determine the system page size if possible */
#if (!defined(_SC_PAGESIZE) && defined(_SC_PAGE_SIZE))
#define _SC_PAGESIZE _SC_PAGE_SIZE
#endif
#ifdef _SC_PAGESIZE
	sysval = sysconf(_SC_PAGESIZE);
	if (sysval > 0)
		sys_page_size = sysval;
#endif /* _SC_PAGESIZE */

	setbuf(stdout, NULL);
	setbuf(stderr, NULL);
	memset(&param, 0, sizeof(struct ext2_super_block));
	param.s_rev_level = 1;  /* Create revision 1 filesystems now */
	param.s_feature_incompat |= EXT2_FEATURE_INCOMPAT_FILETYPE;
	param.s_feature_ro_compat |= EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER;

#ifdef __linux__
	linux_version_code = get_linux_version_code();
	if (linux_version_code && linux_version_code < KERNEL_VERSION(2,2,0)) {
		param.s_rev_level = 0;
		param.s_feature_incompat = 0;
		param.s_feature_compat = 0;
		param.s_feature_ro_compat = 0;
	}
#endif

	/* If called as mkfs.ext3, create a journal inode */
	if (last_char_is(applet_name, '3'))
		journal_size = -1;

	while ((c = getopt (argc, argv,
		    "b:cE:f:g:i:jl:m:no:qr:R:s:tvI:J:ST:FL:M:N:O:V")) != EOF) {
		switch (c) {
		case 'b':
			blocksize = xatou_range(optarg, EXT2_MIN_BLOCK_SIZE, EXT2_MAX_BLOCK_SIZE);
			mke2fs_warning_msg((blocksize > 4096),
				"blocksize %d not usable on most systems",
				blocksize);
			param.s_log_block_size =
				int_log2(blocksize >> EXT2_MIN_BLOCK_LOG_SIZE);
			break;
		case 'c':	/* Check for bad blocks */
		case 't':	/* deprecated */
			cflag++;
			break;
		case 'f':
			size = xatou_range(optarg, EXT2_MIN_BLOCK_SIZE, EXT2_MAX_BLOCK_SIZE);
			param.s_log_frag_size =
				int_log2(size >> EXT2_MIN_BLOCK_LOG_SIZE);
			mke2fs_warning_msg(1, "fragments not supported. Ignoring -f option");
			break;
		case 'g':
			param.s_blocks_per_group = xatou32(optarg);
			if ((param.s_blocks_per_group % 8) != 0) {
				bb_error_msg_and_die("blocks per group must be multiple of 8");
			}
			break;
		case 'i':
			/* Huh? is "* 1024" correct? */
			inode_ratio = xatou_range(optarg, EXT2_MIN_BLOCK_SIZE, EXT2_MAX_BLOCK_SIZE * 1024);
			break;
		case 'J':
			parse_journal_opts(&journal_device, &journal_flags, &journal_size, optarg);
			break;
		case 'j':
			param.s_feature_compat |=
				EXT3_FEATURE_COMPAT_HAS_JOURNAL;
			if (!journal_size)
				journal_size = -1;
			break;
		case 'l':
			bad_blocks_filename = optarg;
			break;
		case 'm':
			reserved_ratio = xatou_range(optarg, 0, 50);
			break;
		case 'n':