566 lines
18 KiB
C
566 lines
18 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* mkfs_ext2: utility to create EXT2 filesystem
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* inspired by genext2fs
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*
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* Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
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*
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* Licensed under GPLv2, see file LICENSE in this tarball for details.
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*/
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#include "libbb.h"
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#include <linux/fs.h>
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#include <linux/ext2_fs.h>
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#include "volume_id/volume_id_internal.h"
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#define ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
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#define ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX 1
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// from e2fsprogs
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#define s_reserved_gdt_blocks s_padding1
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#define s_mkfs_time s_reserved[0]
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#define s_flags s_reserved[22]
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#define EXT2_HASH_HALF_MD4 1
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#define EXT2_FLAGS_SIGNED_HASH 0x0001
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// whiteout: for writable overlays
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//#define LINUX_S_IFWHT 0160000
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//#define EXT2_FEATURE_INCOMPAT_WHITEOUT 0x0020
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// storage helper
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void BUG_unsupported_field_size(void);
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#define STORE_LE(field, value) \
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do { \
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if (sizeof(field) == 4) \
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field = cpu_to_le32(value); \
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else if (sizeof(field) == 2) \
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field = cpu_to_le16(value); \
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else if (sizeof(field) == 1) \
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field = (value); \
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else \
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BUG_unsupported_field_size(); \
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} while (0)
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// All fields are little-endian
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struct ext2_dir {
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uint32_t inode1;
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uint16_t rec_len1;
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uint8_t name_len1;
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uint8_t file_type1;
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char name1[4];
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uint32_t inode2;
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uint16_t rec_len2;
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uint8_t name_len2;
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uint8_t file_type2;
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char name2[4];
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uint32_t inode3;
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uint16_t rec_len3;
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uint8_t name_len3;
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uint8_t file_type3;
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char name3[12];
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};
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static unsigned int_log2(unsigned arg)
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{
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unsigned r = 0;
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while ((arg >>= 1) != 0)
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r++;
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return r;
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}
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// taken from mkfs_minix.c. libbb candidate?
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static unsigned div_roundup(uint32_t size, uint32_t n)
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{
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// Overflow-resistant
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uint32_t res = size / n;
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if (res * n != size)
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res++;
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return res;
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}
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static void allocate(uint8_t *bitmap, uint32_t blocksize, uint32_t start, uint32_t end)
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{
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uint32_t i;
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memset(bitmap, 0, blocksize);
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i = start / 8;
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memset(bitmap, 0xFF, i);
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bitmap[i] = 0xFF >> (8-(start&7));
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//bb_info_msg("ALLOC: [%u][%u][%u]: [%u]:=[%x]", blocksize, start, end, blocksize - end/8 - 1, (uint8_t)(0xFF << (8-(end&7))));
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i = end / 8;
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bitmap[blocksize - i - 1] = 0xFF << (8 - (end & 7));
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memset(bitmap + blocksize - i, 0xFF, i); // N.B. no overflow here!
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}
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static uint32_t has_super(uint32_t x)
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{
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// 0, 1 and powers of 3, 5, 7 up to 2^32 limit
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static const uint32_t supers[] = {
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0, 1, 3, 5, 7, 9, 25, 27, 49, 81, 125, 243, 343, 625, 729,
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2187, 2401, 3125, 6561, 15625, 16807, 19683, 59049, 78125,
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117649, 177147, 390625, 531441, 823543, 1594323, 1953125,
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4782969, 5764801, 9765625, 14348907, 40353607, 43046721,
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48828125, 129140163, 244140625, 282475249, 387420489,
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1162261467, 1220703125, 1977326743, 3486784401/* >2^31 */,
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};
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const uint32_t *sp = supers + ARRAY_SIZE(supers);
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while (1) {
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sp--;
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if (x == *sp)
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return 1;
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if (x > *sp)
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return 0;
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}
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}
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/* Standard mke2fs 1.41.9:
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* Usage: mke2fs [-c|-l filename] [-b block-size] [-f fragment-size]
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* [-i bytes-per-inode] [-I inode-size] [-J journal-options]
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* [-G meta group size] [-N number-of-inodes]
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* [-m reserved-blocks-percentage] [-o creator-os]
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* [-g blocks-per-group] [-L volume-label] [-M last-mounted-directory]
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* [-O feature[,...]] [-r fs-revision] [-E extended-option[,...]]
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* [-T fs-type] [-U UUID] [-jnqvFSV] device [blocks-count]
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*/
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// N.B. not commented below options are taken and silently ignored
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enum {
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OPT_c = 1 << 0,
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OPT_l = 1 << 1,
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OPT_b = 1 << 2, // block size, in bytes
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OPT_f = 1 << 3,
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OPT_i = 1 << 4, // bytes per inode
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OPT_I = 1 << 5,
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OPT_J = 1 << 6,
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OPT_G = 1 << 7,
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OPT_N = 1 << 8,
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OPT_m = 1 << 9, // percentage of blocks reserved for superuser
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OPT_o = 1 << 10,
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OPT_g = 1 << 11,
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OPT_L = 1 << 12, // label
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OPT_M = 1 << 13,
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OPT_O = 1 << 14,
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OPT_r = 1 << 15,
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OPT_E = 1 << 16,
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OPT_T = 1 << 17,
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OPT_U = 1 << 18,
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OPT_j = 1 << 19,
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OPT_n = 1 << 20, // dry run: do not write anything
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OPT_q = 1 << 21,
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OPT_v = 1 << 22,
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OPT_F = 1 << 23,
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OPT_S = 1 << 24,
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//OPT_V = 1 << 25, // -V version. bbox applets don't support that
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};
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#define fd 3 /* predefined output descriptor */
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static void PUT(uint64_t off, void *buf, uint32_t size)
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{
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// bb_info_msg("PUT[%llu]:[%u]", off, size);
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xlseek(fd, off, SEEK_SET);
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xwrite(fd, buf, size);
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}
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int mkfs_ext2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
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{
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unsigned i, pos, n;
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unsigned bs, bpi;
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unsigned blocksize, blocksize_log2;
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unsigned nreserved = 5;
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unsigned long long kilobytes;
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uint32_t nblocks;
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uint32_t ngroups;
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uint32_t bytes_per_inode;
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uint32_t first_data_block;
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uint32_t ninodes_per_group;
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uint32_t gdtsz, itsz;
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time_t timestamp;
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unsigned opts;
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const char *label;
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struct stat st;
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struct ext2_super_block *sb; // superblock
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struct ext2_group_desc *gd; // group descriptors
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struct ext2_inode *inode;
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struct ext2_dir *dir;
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uint8_t *buf;
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opt_complementary = "-1:b+:m+:i+";
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opts = getopt32(argv, "cl:b:f:i:I:J:G:N:m:o:g:L:M:O:r:E:T:U:jnqvFS",
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NULL, &bs, NULL, &bpi, NULL, NULL, NULL, NULL,
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&nreserved, NULL, NULL, &label, NULL, NULL, NULL, NULL, NULL, NULL);
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argv += optind; // argv[0] -- device
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// reserved blocks percentage
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if (nreserved > 50)
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bb_error_msg_and_die("-%c is bad", 'm');
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// check the device is a block device
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xmove_fd(xopen(argv[0], O_WRONLY), fd);
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fstat(fd, &st);
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if (!S_ISBLK(st.st_mode) && !(opts & OPT_F))
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bb_error_msg_and_die("not a block device");
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// check if it is mounted
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// N.B. what if we format a file? find_mount_point will return false negative since
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// it is loop block device which mounted!
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if (find_mount_point(argv[0], 0))
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bb_error_msg_and_die("can't format mounted filesystem");
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// open the device, get size in kbytes
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if (argv[1]) {
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kilobytes = xatoull(argv[1]);
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} else {
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kilobytes = (uoff_t)xlseek(fd, 0, SEEK_END) / 1024;
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}
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bytes_per_inode = 16384;
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if (kilobytes < 512*1024)
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bytes_per_inode = 4096;
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if (kilobytes < 3*1024)
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bytes_per_inode = 8192;
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if (opts & OPT_i)
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bytes_per_inode = bpi;
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// block size is a multiple of 1024
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blocksize = 1024;
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if (kilobytes >= 512*1024) // mke2fs 1.41.9 compat
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blocksize = 4096;
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if (EXT2_MAX_BLOCK_SIZE > 4096) {
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// kilobytes >> 22 == size in 4gigabyte chunks.
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// if it is >= 16k gigs, blocksize must be increased.
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// Try "mke2fs -F image_std $((16 * 1024*1024*1024))"
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while ((kilobytes >> 22) >= blocksize)
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blocksize *= 2;
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}
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if (opts & OPT_b)
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blocksize = bs;
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if (blocksize < EXT2_MIN_BLOCK_SIZE
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|| blocksize > EXT2_MAX_BLOCK_SIZE
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|| (blocksize & (blocksize - 1)) // not power of 2
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) {
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bb_error_msg_and_die("blocksize %u is bad", blocksize);
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}
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blocksize_log2 = int_log2(blocksize);
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kilobytes >>= (blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
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// nblocks: the total number of blocks in the filesystem
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nblocks = kilobytes;
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if (nblocks != kilobytes)
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bb_error_msg_and_die("block count doesn't fit in 32 bits");
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if (nblocks < 8)
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bb_error_msg_and_die("need >= 8 blocks");
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#define kilobytes kilobytes_unused_after_this
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// number of bits in one block, i.e. 8*blocksize
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#define blocks_per_group (8 * blocksize)
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/* e2fsprogs-1.41.9
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overhead = 2 + fs->inode_blocks_per_group;
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if (has_super(fs->group_desc_count - 1))
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overhead += 1 + fs->desc_blocks + super->s_reserved_gdt_blocks;
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rem = (nblocks - first_data_block) % blocks_per_group);
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if ((fs->group_desc_count == 1) && rem && (rem < overhead)) {
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retval = EXT2_ET_TOOSMALL;
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goto cleanup;
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}
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if (rem && (rem < overhead+50)) {
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nblocks -= rem;
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goto retry;
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}
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*/
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// N.B. a block group can have no more than blocks_per_group blocks
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first_data_block = (EXT2_MIN_BLOCK_SIZE == blocksize);
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ngroups = div_roundup(nblocks - first_data_block, blocks_per_group);
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if (0 == ngroups)
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bb_error_msg_and_die("ngroups");
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{
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// ninodes is the total number of inodes (files) in the file system
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uint32_t ninodes = nblocks / (bytes_per_inode >> blocksize_log2);
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if (ninodes < EXT2_GOOD_OLD_FIRST_INO+1)
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ninodes = EXT2_GOOD_OLD_FIRST_INO+1;
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ninodes_per_group = div_roundup(ninodes, ngroups);
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// minimum number because the first EXT2_GOOD_OLD_FIRST_INO-1 are reserved
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if (ninodes_per_group < 16)
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ninodes_per_group = 16;
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}
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// TODO: 5?/5 WE MUST NOT DEPEND ON WHETHER DEVICE IS /dev/zero 'ed OR NOT
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// TODO: 3/5 refuse if mounted
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// TODO: 4/5 compat options
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// TODO: 1/5 sanity checks
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// TODO: 0/5 more verbose error messages
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// TODO: 0/5 info printing
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// TODO: 2/5 bigendianness! Spot where it comes to play! sb->, gd->
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// TODO: 2/5 reserved GDT: how to mark but not allocate?
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// TODO: 3/5 dir_index?
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// fill the superblock
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sb = xzalloc(blocksize);
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sb->s_rev_level = 1; // revision 1 filesystem
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sb->s_magic = EXT2_SUPER_MAGIC;
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sb->s_inode_size = sizeof(*inode);
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sb->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
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sb->s_log_block_size = sb->s_log_frag_size = blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE;
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// first 1024 bytes of the device are for boot record. If block size is 1024 bytes, then
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// the first block available for data is 1, otherwise 0
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sb->s_first_data_block = first_data_block; // 0 or 1
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// block and inode bitmaps occupy no more than one block, so maximum number of blocks is
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sb->s_blocks_per_group = sb->s_frags_per_group = blocks_per_group;
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timestamp = time(NULL);
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sb->s_mkfs_time = sb->s_wtime = sb->s_lastcheck = timestamp;
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sb->s_state = 1;
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sb->s_creator_os = EXT2_OS_LINUX;
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sb->s_checkinterval = 24*60*60 * 180; // 180 days
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sb->s_errors = EXT2_ERRORS_DEFAULT;
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sb->s_feature_compat = EXT2_FEATURE_COMPAT_SUPP
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| (EXT2_FEATURE_COMPAT_RESIZE_INO * ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT)
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| (EXT2_FEATURE_COMPAT_DIR_INDEX * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX)
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;
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// e2fsprogs-1.41.9 doesn't like EXT2_FEATURE_INCOMPAT_WHITEOUT
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sb->s_feature_incompat = EXT2_FEATURE_INCOMPAT_FILETYPE;// | EXT2_FEATURE_INCOMPAT_WHITEOUT;
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sb->s_feature_ro_compat = EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER;
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sb->s_flags = EXT2_FLAGS_SIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX;
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generate_uuid(sb->s_uuid);
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if (ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX) {
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sb->s_def_hash_version = EXT2_HASH_HALF_MD4;
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generate_uuid((uint8_t *)sb->s_hash_seed);
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}
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/*
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* From e2fsprogs: add "jitter" to the superblock's check interval so that we
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* don't check all the filesystems at the same time. We use a
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* kludgy hack of using the UUID to derive a random jitter value.
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*/
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sb->s_max_mnt_count = EXT2_DFL_MAX_MNT_COUNT
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+ (sb->s_uuid[ARRAY_SIZE(sb->s_uuid)-1] % EXT2_DFL_MAX_MNT_COUNT);
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sb->s_blocks_count = nblocks;
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// reserve blocks for superuser
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sb->s_r_blocks_count = ((uint64_t) nblocks * nreserved) / 100;
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gdtsz = div_roundup(ngroups, EXT2_DESC_PER_BLOCK(sb));
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/*
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* From e2fsprogs: Calculate the number of GDT blocks to reserve for online
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* filesystem growth.
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* The absolute maximum number of GDT blocks we can reserve is determined by
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* the number of block pointers that can fit into a single block.
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*/
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/* We set it at 1024x the current filesystem size, or
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* the upper block count limit (2^32), whichever is lower.
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*/
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if (ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT) {
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uint32_t rgdtsz = 0xFFFFFFFF; // maximum block number
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if (nblocks < rgdtsz / 1024)
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rgdtsz = nblocks * 1024;
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rgdtsz = div_roundup(rgdtsz - first_data_block, blocks_per_group);
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rgdtsz = div_roundup(rgdtsz, EXT2_DESC_PER_BLOCK(sb)) - gdtsz;
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if (rgdtsz > EXT2_ADDR_PER_BLOCK(sb))
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rgdtsz = EXT2_ADDR_PER_BLOCK(sb);
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STORE_LE(sb->s_reserved_gdt_blocks, rgdtsz);
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gdtsz += rgdtsz;
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}
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// N.B. a block group can have no more than 8*blocksize inodes
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if (ninodes_per_group > blocks_per_group)
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ninodes_per_group = blocks_per_group;
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// adjust inodes per group so they completely fill the inode table blocks in the descriptor
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ninodes_per_group = (div_roundup(ninodes_per_group * EXT2_INODE_SIZE(sb), blocksize) << blocksize_log2) / EXT2_INODE_SIZE(sb);
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// make sure the number of inodes per group is a multiple of 8
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ninodes_per_group &= ~7;
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sb->s_inodes_per_group = ninodes_per_group;// = div_roundup(ninodes_per_group * sb->s_inode_size, blocksize);
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// total ninodes
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sb->s_inodes_count = ninodes_per_group * ngroups;
|
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|
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itsz = ninodes_per_group * sb->s_inode_size / blocksize;
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sb->s_free_inodes_count = sb->s_inodes_count - EXT2_GOOD_OLD_FIRST_INO;
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|
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// write the label, if any
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if (opts & OPT_L)
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safe_strncpy((char *)sb->s_volume_name, label, sizeof(sb->s_volume_name));
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|
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#if 1
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/* if (fs_param.s_blocks_count != s->s_blocks_count)
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fprintf(stderr, _("warning: %u blocks unused.\n\n"),
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fs_param.s_blocks_count - s->s_blocks_count);
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*/
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printf(
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"Filesystem label=%s\n"
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"OS type: Linux\n"
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"Block size=%u (log=%u)\n"
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"Fragment size=%u (log=%u)\n"
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"%u inodes, %u blocks\n"
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"%u blocks (%u%%) reserved for the super user\n"
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"First data block=%u\n"
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"Maximum filesystem blocks=%u\n"
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"%u block groups\n"
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"%u blocks per group, %u fragments per group\n"
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"%u inodes per group"
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, (char *)sb->s_volume_name
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, blocksize, sb->s_log_block_size
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, blocksize, sb->s_log_block_size
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, sb->s_inodes_count, sb->s_blocks_count
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, sb->s_r_blocks_count, nreserved
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, first_data_block
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, gdtsz * EXT2_DESC_PER_BLOCK(sb) * blocks_per_group
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, ngroups
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, blocks_per_group, blocks_per_group
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, ninodes_per_group
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);
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{
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const char *fmt = "\nSuperblock backups stored on blocks:\n"
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"\t%u";
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pos = first_data_block;
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for (i = 1; i < ngroups; i++) {
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pos += blocks_per_group;
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if (has_super(i)) {
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printf(fmt, (unsigned)pos);
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fmt = ", %u";
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}
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}
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}
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bb_putchar('\n');
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#endif
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|
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if (opts & OPT_n)
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goto done;
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|
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// fill group descriptors
|
|
gd = xzalloc(gdtsz * blocksize);
|
|
sb->s_free_blocks_count = 0;
|
|
for (i = 0, pos = first_data_block, n = nblocks;
|
|
i < ngroups;
|
|
i++, pos += blocks_per_group, n -= blocks_per_group
|
|
) {
|
|
uint32_t overhead = pos + (has_super(i) ? (1/*sb*/ + gdtsz) : 0);
|
|
gd[i].bg_block_bitmap = overhead + 0;
|
|
gd[i].bg_inode_bitmap = overhead + 1;
|
|
gd[i].bg_inode_table = overhead + 2;
|
|
overhead = overhead - pos + 1/*bbmp*/ + 1/*ibmp*/ + itsz;
|
|
gd[i].bg_free_inodes_count = ninodes_per_group;
|
|
//gd[i].bg_used_dirs_count = 0;
|
|
// N.B. both root and lost+found dirs are within the first block group, thus +2
|
|
if (0 == i) {
|
|
overhead += 2;
|
|
gd[i].bg_used_dirs_count = 2;
|
|
gd[i].bg_free_inodes_count -= EXT2_GOOD_OLD_FIRST_INO;
|
|
}
|
|
// N.B. the following is pure heuristics!
|
|
// Likely to cope with 1024-byte blocks, when first block is for boot sectors
|
|
if (ngroups-1 == i) {
|
|
overhead += first_data_block;
|
|
}
|
|
gd[i].bg_free_blocks_count = (n < blocks_per_group ? n : blocks_per_group) - overhead;
|
|
sb->s_free_blocks_count += gd[i].bg_free_blocks_count;
|
|
}
|
|
STORE_LE(sb->s_free_blocks_count, sb->s_free_blocks_count);
|
|
|
|
// dump filesystem skeleton structures
|
|
// printf("Writing superblocks and filesystem accounting information: ");
|
|
buf = xmalloc(blocksize);
|
|
for (i = 0, pos = first_data_block; i < ngroups; i++, pos += blocks_per_group) {
|
|
uint32_t overhead = has_super(i) ? (1/*sb*/ + gdtsz) : 0;
|
|
uint32_t start;
|
|
uint32_t end;
|
|
|
|
// dump superblock and group descriptors and their backups
|
|
if (overhead) { // N.B. in fact, we want (has_super(i)) condition, but it is equal to (overhead != 0) and is cheaper
|
|
// N.B. 1024 byte blocks are special
|
|
PUT(((uint64_t)pos << blocksize_log2) + ((0 == i && 0 == first_data_block) ? 1024 : 0), sb, 1024);//blocksize);
|
|
PUT(((uint64_t)pos << blocksize_log2) + blocksize, gd, gdtsz * blocksize);
|
|
}
|
|
|
|
start = overhead + 1/*bbmp*/ + 1/*ibmp*/ + itsz;
|
|
if (i == 0)
|
|
start += 2; // for "/" and "/lost+found"
|
|
end = blocks_per_group - (start + gd[i].bg_free_blocks_count);
|
|
|
|
// mark preallocated blocks as allocated
|
|
allocate(buf, blocksize, start, end);
|
|
// dump block bitmap
|
|
PUT((uint64_t)(pos + overhead) * blocksize, buf, blocksize);
|
|
|
|
// mark preallocated inodes as allocated
|
|
allocate(buf, blocksize,
|
|
ninodes_per_group - gd[i].bg_free_inodes_count,
|
|
blocks_per_group - ninodes_per_group
|
|
);
|
|
// dump inode bitmap
|
|
//PUT((uint64_t)(pos + overhead + 1) * blocksize, buf, blocksize);
|
|
//but it's right after block bitmap, so we can just:
|
|
xwrite(fd, buf, blocksize);
|
|
}
|
|
|
|
// zero boot sectors
|
|
memset(buf, 0, blocksize);
|
|
PUT(0, buf, 1024); // N.B. 1024 <= blocksize
|
|
// zero inode tables
|
|
for (i = 0; i < ngroups; ++i)
|
|
for (n = 0; n < itsz; ++n)
|
|
PUT((uint64_t)(gd[i].bg_inode_table + n) * blocksize, buf, blocksize);
|
|
|
|
// prepare directory inode
|
|
inode = (struct ext2_inode *)buf;
|
|
STORE_LE(inode->i_mode, S_IFDIR | S_IRWXU | S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
|
|
STORE_LE(inode->i_mtime, timestamp);
|
|
STORE_LE(inode->i_atime, timestamp);
|
|
STORE_LE(inode->i_ctime, timestamp);
|
|
STORE_LE(inode->i_size, blocksize);
|
|
// N.B. inode->i_blocks stores the number of 512 byte data blocks. Why on Earth?!
|
|
STORE_LE(inode->i_blocks, blocksize / 512);
|
|
|
|
// dump root dir inode
|
|
STORE_LE(inode->i_links_count, 3); // "/.", "/..", "/lost+found/.." point to this inode
|
|
STORE_LE(inode->i_block[0], gd[0].bg_inode_table + itsz);
|
|
PUT(((uint64_t)gd[0].bg_inode_table << blocksize_log2) + (EXT2_ROOT_INO-1) * sizeof(*inode), buf, sizeof(*inode));
|
|
|
|
// dump lost+found dir inode
|
|
STORE_LE(inode->i_links_count, 2); // both "/lost+found" and "/lost+found/." point to this inode
|
|
STORE_LE(inode->i_block[0], inode->i_block[0]+1); // use next block //= gd[0].bg_inode_table + itsz + 1;
|
|
PUT(((uint64_t)gd[0].bg_inode_table << blocksize_log2) + (EXT2_GOOD_OLD_FIRST_INO-1) * sizeof(*inode), buf, sizeof(*inode));
|
|
|
|
// dump directories
|
|
memset(buf, 0, blocksize);
|
|
dir = (struct ext2_dir *)buf;
|
|
|
|
// dump lost+found dir block
|
|
STORE_LE(dir->inode1, EXT2_GOOD_OLD_FIRST_INO);
|
|
STORE_LE(dir->rec_len1, 12);
|
|
STORE_LE(dir->name_len1, 1);
|
|
STORE_LE(dir->file_type1, EXT2_FT_DIR);
|
|
dir->name1[0] = '.';
|
|
STORE_LE(dir->inode2, EXT2_ROOT_INO);
|
|
STORE_LE(dir->rec_len2, blocksize - 12);
|
|
STORE_LE(dir->name_len2, 2);
|
|
STORE_LE(dir->file_type2, EXT2_FT_DIR);
|
|
dir->name2[0] = '.'; dir->name2[1] = '.';
|
|
PUT((uint64_t)(gd[0].bg_inode_table + itsz + 1) * blocksize, buf, blocksize);
|
|
|
|
// dump root dir block
|
|
STORE_LE(dir->inode1, EXT2_ROOT_INO);
|
|
STORE_LE(dir->rec_len2, 12);
|
|
STORE_LE(dir->inode3, EXT2_GOOD_OLD_FIRST_INO);
|
|
STORE_LE(dir->rec_len3, blocksize - 12 - 12);
|
|
STORE_LE(dir->name_len3, 10);
|
|
STORE_LE(dir->file_type3, EXT2_FT_DIR);
|
|
strcpy(dir->name3, "lost+found");
|
|
PUT((uint64_t)(gd[0].bg_inode_table + itsz + 0) * blocksize, buf, blocksize);
|
|
|
|
// bb_info_msg("done\n"
|
|
// "This filesystem will be automatically checked every %u mounts or\n"
|
|
// "180 days, whichever comes first. Use tune2fs -c or -i to override.",
|
|
// sb->s_max_mnt_count
|
|
// );
|
|
|
|
done:
|
|
// cleanup
|
|
if (ENABLE_FEATURE_CLEAN_UP) {
|
|
free(buf);
|
|
free(gd);
|
|
free(sb);
|
|
}
|
|
|
|
xclose(fd);
|
|
return EXIT_SUCCESS;
|
|
}
|