#include "libbb.h"
#include <linux/fs.h>
#include <linux/ext2_fs.h>
+#include <sys/user.h> /* PAGE_SIZE */
+#ifndef PAGE_SIZE
+# define PAGE_SIZE 4096
+#endif
#include "volume_id/volume_id_internal.h"
#define ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
//#define LINUX_S_IFWHT 0160000
//#define EXT2_FEATURE_INCOMPAT_WHITEOUT 0x0020
-// storage helper
-void BUG_unsupported_field_size(void);
+// storage helpers
+char BUG_wrong_field_size(void);
#define STORE_LE(field, value) \
do { \
if (sizeof(field) == 4) \
else if (sizeof(field) == 1) \
field = (value); \
else \
- BUG_unsupported_field_size(); \
+ BUG_wrong_field_size(); \
} while (0)
+#define FETCH_LE32(field) \
+ (sizeof(field) == 4 ? cpu_to_le32(field) : BUG_wrong_field_size())
+
// All fields are little-endian
struct ext2_dir {
uint32_t inode1;
}
// taken from mkfs_minix.c. libbb candidate?
-static unsigned div_roundup(uint32_t size, uint32_t n)
+static unsigned div_roundup(uint64_t size, uint32_t n)
{
// Overflow-resistant
- uint32_t res = size / n;
+ uint64_t res = size / n;
if (res * n != size)
res++;
return res;
memset(bitmap, 0, blocksize);
i = start / 8;
memset(bitmap, 0xFF, i);
- bitmap[i] = 0xFF >> (8-(start&7));
-//bb_info_msg("ALLOC: [%u][%u][%u]: [%u]:=[%x]", blocksize, start, end, blocksize - end/8 - 1, (uint8_t)(0xFF << (8-(end&7))));
+ bitmap[i] = 0xFF >> (8 - (start & 7));
+//bb_info_msg("ALLOC: [%u][%u][%u]: [%u-%u]:=[%x],[%x]", blocksize, start, end, start/8, blocksize - end/8 - 1, 0xFF >> (8 - (start & 7)), (uint8_t)(0xFF << (8-(end&7))));
i = end / 8;
bitmap[blocksize - i - 1] = 0xFF << (8 - (end & 7));
memset(bitmap + blocksize - i, 0xFF, i); // N.B. no overflow here!
unsigned blocksize, blocksize_log2;
unsigned nreserved = 5;
unsigned long long kilobytes;
- uint32_t nblocks;
+ uint32_t nblocks, nblocks_full;
uint32_t ngroups;
uint32_t bytes_per_inode;
uint32_t first_data_block;
- uint32_t ninodes_per_group;
+ uint32_t inodes_per_group;
uint32_t gdtsz, itsz;
time_t timestamp;
unsigned opts;
- const char *label;
+ const char *label = "";
struct stat st;
struct ext2_super_block *sb; // superblock
struct ext2_group_desc *gd; // group descriptors
nblocks = kilobytes;
if (nblocks != kilobytes)
bb_error_msg_and_die("block count doesn't fit in 32 bits");
+#define kilobytes kilobytes_unused_after_this
+
+ if (blocksize < PAGE_SIZE)
+ nblocks &= ~((PAGE_SIZE / blocksize)-1);
+
+ // N.B. killing e2fsprogs feature! Unused blocks don't account in calculations
+ nblocks_full = nblocks;
+ retry:
if (nblocks < 8)
bb_error_msg_and_die("need >= 8 blocks");
-#define kilobytes kilobytes_unused_after_this
// number of bits in one block, i.e. 8*blocksize
#define blocks_per_group (8 * blocksize)
-/* e2fsprogs-1.41.9
- overhead = 2 + fs->inode_blocks_per_group;
- if (has_super(fs->group_desc_count - 1))
- overhead += 1 + fs->desc_blocks + super->s_reserved_gdt_blocks;
- rem = (nblocks - first_data_block) % blocks_per_group);
- if ((fs->group_desc_count == 1) && rem && (rem < overhead)) {
- retval = EXT2_ET_TOOSMALL;
- goto cleanup;
- }
- if (rem && (rem < overhead+50)) {
- nblocks -= rem;
- goto retry;
- }
-*/
-
// N.B. a block group can have no more than blocks_per_group blocks
first_data_block = (EXT2_MIN_BLOCK_SIZE == blocksize);
ngroups = div_roundup(nblocks - first_data_block, blocks_per_group);
if (0 == ngroups)
bb_error_msg_and_die("ngroups");
- {
- // ninodes is the total number of inodes (files) in the file system
- uint32_t ninodes = nblocks / (bytes_per_inode >> blocksize_log2);
- if (ninodes < EXT2_GOOD_OLD_FIRST_INO+1)
- ninodes = EXT2_GOOD_OLD_FIRST_INO+1;
- ninodes_per_group = div_roundup(ninodes, ngroups);
- // minimum number because the first EXT2_GOOD_OLD_FIRST_INO-1 are reserved
- if (ninodes_per_group < 16)
- ninodes_per_group = 16;
- }
-
- // TODO: 5?/5 WE MUST NOT DEPEND ON WHETHER DEVICE IS /dev/zero 'ed OR NOT
- // TODO: 3/5 refuse if mounted
- // TODO: 4/5 compat options
- // TODO: 1/5 sanity checks
- // TODO: 0/5 more verbose error messages
- // TODO: 0/5 info printing
- // TODO: 2/5 bigendianness! Spot where it comes to play! sb->, gd->
- // TODO: 2/5 reserved GDT: how to mark but not allocate?
- // TODO: 3/5 dir_index?
-
- // fill the superblock
- sb = xzalloc(blocksize);
- sb->s_rev_level = 1; // revision 1 filesystem
- sb->s_magic = EXT2_SUPER_MAGIC;
- sb->s_inode_size = sizeof(*inode);
- sb->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
- sb->s_log_block_size = sb->s_log_frag_size = blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE;
- // first 1024 bytes of the device are for boot record. If block size is 1024 bytes, then
- // the first block available for data is 1, otherwise 0
- sb->s_first_data_block = first_data_block; // 0 or 1
- // block and inode bitmaps occupy no more than one block, so maximum number of blocks is
- sb->s_blocks_per_group = sb->s_frags_per_group = blocks_per_group;
- timestamp = time(NULL);
- sb->s_mkfs_time = sb->s_wtime = sb->s_lastcheck = timestamp;
- sb->s_state = 1;
- sb->s_creator_os = EXT2_OS_LINUX;
- sb->s_checkinterval = 24*60*60 * 180; // 180 days
- sb->s_errors = EXT2_ERRORS_DEFAULT;
- sb->s_feature_compat = EXT2_FEATURE_COMPAT_SUPP
- | (EXT2_FEATURE_COMPAT_RESIZE_INO * ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT)
- | (EXT2_FEATURE_COMPAT_DIR_INDEX * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX)
- ;
- // e2fsprogs-1.41.9 doesn't like EXT2_FEATURE_INCOMPAT_WHITEOUT
- sb->s_feature_incompat = EXT2_FEATURE_INCOMPAT_FILETYPE;// | EXT2_FEATURE_INCOMPAT_WHITEOUT;
- sb->s_feature_ro_compat = EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER;
- sb->s_flags = EXT2_FLAGS_SIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX;
- generate_uuid(sb->s_uuid);
- if (ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX) {
- sb->s_def_hash_version = EXT2_HASH_HALF_MD4;
- generate_uuid((uint8_t *)sb->s_hash_seed);
- }
- /*
- * From e2fsprogs: add "jitter" to the superblock's check interval so that we
- * don't check all the filesystems at the same time. We use a
- * kludgy hack of using the UUID to derive a random jitter value.
- */
- sb->s_max_mnt_count = EXT2_DFL_MAX_MNT_COUNT
- + (sb->s_uuid[ARRAY_SIZE(sb->s_uuid)-1] % EXT2_DFL_MAX_MNT_COUNT);
-
- sb->s_blocks_count = nblocks;
-
- // reserve blocks for superuser
- sb->s_r_blocks_count = ((uint64_t) nblocks * nreserved) / 100;
-
- gdtsz = div_roundup(ngroups, EXT2_DESC_PER_BLOCK(sb));
- /*
- * From e2fsprogs: Calculate the number of GDT blocks to reserve for online
- * filesystem growth.
- * The absolute maximum number of GDT blocks we can reserve is determined by
- * the number of block pointers that can fit into a single block.
- */
- /* We set it at 1024x the current filesystem size, or
- * the upper block count limit (2^32), whichever is lower.
- */
+ gdtsz = div_roundup(ngroups, blocksize / sizeof(*gd));
+ // TODO: reserved blocks must be marked as such in the bitmaps,
+ // or resulting filesystem is corrupt
if (ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT) {
+ /*
+ * From e2fsprogs: Calculate the number of GDT blocks to reserve for online
+ * filesystem growth.
+ * The absolute maximum number of GDT blocks we can reserve is determined by
+ * the number of block pointers that can fit into a single block.
+ * We set it at 1024x the current filesystem size, or
+ * the upper block count limit (2^32), whichever is lower.
+ */
uint32_t rgdtsz = 0xFFFFFFFF; // maximum block number
if (nblocks < rgdtsz / 1024)
rgdtsz = nblocks * 1024;
rgdtsz = div_roundup(rgdtsz - first_data_block, blocks_per_group);
- rgdtsz = div_roundup(rgdtsz, EXT2_DESC_PER_BLOCK(sb)) - gdtsz;
- if (rgdtsz > EXT2_ADDR_PER_BLOCK(sb))
- rgdtsz = EXT2_ADDR_PER_BLOCK(sb);
- STORE_LE(sb->s_reserved_gdt_blocks, rgdtsz);
+ rgdtsz = div_roundup(rgdtsz, blocksize / sizeof(*gd)) - gdtsz;
+ if (rgdtsz > blocksize / sizeof(uint32_t))
+ rgdtsz = blocksize / sizeof(uint32_t);
+ //TODO: STORE_LE(sb->s_reserved_gdt_blocks, rgdtsz);
gdtsz += rgdtsz;
}
- // N.B. a block group can have no more than 8*blocksize inodes
- if (ninodes_per_group > blocks_per_group)
- ninodes_per_group = blocks_per_group;
- // adjust inodes per group so they completely fill the inode table blocks in the descriptor
- ninodes_per_group = (div_roundup(ninodes_per_group * EXT2_INODE_SIZE(sb), blocksize) << blocksize_log2) / EXT2_INODE_SIZE(sb);
- // make sure the number of inodes per group is a multiple of 8
- ninodes_per_group &= ~7;
- sb->s_inodes_per_group = ninodes_per_group;// = div_roundup(ninodes_per_group * sb->s_inode_size, blocksize);
- // total ninodes
- sb->s_inodes_count = ninodes_per_group * ngroups;
-
- itsz = ninodes_per_group * sb->s_inode_size / blocksize;
- sb->s_free_inodes_count = sb->s_inodes_count - EXT2_GOOD_OLD_FIRST_INO;
-
- // write the label, if any
- if (opts & OPT_L)
- safe_strncpy((char *)sb->s_volume_name, label, sizeof(sb->s_volume_name));
-
-#if 1
-/* if (fs_param.s_blocks_count != s->s_blocks_count)
- fprintf(stderr, _("warning: %u blocks unused.\n\n"),
- fs_param.s_blocks_count - s->s_blocks_count);
-*/
+ {
+ // N.B. e2fsprogs does as follows!
+ // ninodes is the total number of inodes (files) in the file system
+ uint32_t ninodes = nblocks_full / (blocksize >= 4096 ? 1 : 4096 / blocksize);
+ uint32_t overhead, remainder;
+ if (ninodes < EXT2_GOOD_OLD_FIRST_INO+1)
+ ninodes = EXT2_GOOD_OLD_FIRST_INO+1;
+ inodes_per_group = div_roundup(ninodes, ngroups);
+ // minimum number because the first EXT2_GOOD_OLD_FIRST_INO-1 are reserved
+ if (inodes_per_group < 16)
+ inodes_per_group = 16;
+
+ // N.B. a block group can have no more than 8*blocksize inodes
+ if (inodes_per_group > blocks_per_group)
+ inodes_per_group = blocks_per_group;
+ // adjust inodes per group so they completely fill the inode table blocks in the descriptor
+ inodes_per_group = (div_roundup(inodes_per_group * sizeof(*inode), blocksize) << blocksize_log2) / sizeof(*inode);
+ // make sure the number of inodes per group is a multiple of 8
+ inodes_per_group &= ~7;
+ itsz = div_roundup(inodes_per_group * sizeof(*inode), blocksize);
+
+ // the last block needs more attention: doesn't it too small for possible overhead?
+ overhead = (has_super(ngroups - 1) ? (1/*sb*/ + gdtsz) : 0) + 1/*bbmp*/ + 1/*ibmp*/ + itsz;
+ remainder = (nblocks - first_data_block) % blocks_per_group;
+ if ((1 == ngroups) && remainder && (remainder < overhead))
+ bb_error_msg_and_die("way small device");
+ if (remainder && (remainder < overhead + 50)) {
+//bb_info_msg("CHOP[%u]", remainder);
+ nblocks -= remainder;
+ goto retry;
+ }
+ }
+ // print info
+ if (nblocks_full - nblocks)
+ printf("warning: %u blocks unused\n\n", nblocks_full - nblocks);
printf(
"Filesystem label=%s\n"
"OS type: Linux\n"
"%u block groups\n"
"%u blocks per group, %u fragments per group\n"
"%u inodes per group"
- , (char *)sb->s_volume_name
- , blocksize, sb->s_log_block_size
- , blocksize, sb->s_log_block_size
- , sb->s_inodes_count, sb->s_blocks_count
- , sb->s_r_blocks_count, nreserved
+ , label
+ , blocksize, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE
+ , blocksize, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE
+ , inodes_per_group * ngroups, nblocks
+ //, div_roundup((uint64_t) nblocks * nreserved, 100), nreserved
+ , (unsigned)((uint64_t) nblocks_full * nreserved / 100), nreserved
, first_data_block
- , gdtsz * EXT2_DESC_PER_BLOCK(sb) * blocks_per_group
+ , gdtsz * (blocksize / sizeof(*gd)) * blocks_per_group
, ngroups
, blocks_per_group, blocks_per_group
- , ninodes_per_group
+ , inodes_per_group
);
{
const char *fmt = "\nSuperblock backups stored on blocks:\n"
}
}
bb_putchar('\n');
-#endif
+ // dry run? -> we are done
if (opts & OPT_n)
goto done;
+ // TODO: 3/5 refuse if mounted
+ // TODO: 4/5 compat options
+ // TODO: 1/5 sanity checks
+ // TODO: 0/5 more verbose error messages
+ // TODO: 4/5 bigendianness: recheck, wait for ARM reporters
+ // TODO: 2/5 reserved GDT: how to mark but not allocate?
+ // TODO: 3/5 dir_index?
+
+ // fill the superblock
+ sb = xzalloc(blocksize);
+ STORE_LE(sb->s_rev_level, 1); // revision 1 filesystem
+ STORE_LE(sb->s_magic, EXT2_SUPER_MAGIC);
+ STORE_LE(sb->s_inode_size, sizeof(*inode));
+ STORE_LE(sb->s_first_ino, EXT2_GOOD_OLD_FIRST_INO);
+ STORE_LE(sb->s_log_block_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
+ STORE_LE(sb->s_log_frag_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
+ // first 1024 bytes of the device are for boot record. If block size is 1024 bytes, then
+ // the first block available for data is 1, otherwise 0
+ STORE_LE(sb->s_first_data_block, first_data_block); // 0 or 1
+ // block and inode bitmaps occupy no more than one block, so maximum number of blocks is
+ STORE_LE(sb->s_blocks_per_group, blocks_per_group);
+ STORE_LE(sb->s_frags_per_group, blocks_per_group);
+ // blocks
+ STORE_LE(sb->s_blocks_count, nblocks);
+ // reserve blocks for superuser
+ STORE_LE(sb->s_r_blocks_count, (uint32_t)((uint64_t) nblocks_full * nreserved / 100));
+ // ninodes
+ STORE_LE(sb->s_inodes_per_group, inodes_per_group);
+ STORE_LE(sb->s_inodes_count, inodes_per_group * ngroups);
+ STORE_LE(sb->s_free_inodes_count, inodes_per_group * ngroups - EXT2_GOOD_OLD_FIRST_INO);
+ // timestamps
+ timestamp = time(NULL);
+ STORE_LE(sb->s_mkfs_time, timestamp);
+ STORE_LE(sb->s_wtime, timestamp);
+ STORE_LE(sb->s_lastcheck, timestamp);
+ // misc
+ STORE_LE(sb->s_state, 1); // TODO: what's 1?
+ STORE_LE(sb->s_creator_os, EXT2_OS_LINUX);
+ STORE_LE(sb->s_checkinterval, 24*60*60 * 180); // 180 days
+ STORE_LE(sb->s_errors, EXT2_ERRORS_DEFAULT);
+ STORE_LE(sb->s_feature_compat, EXT2_FEATURE_COMPAT_SUPP
+ | (EXT2_FEATURE_COMPAT_RESIZE_INO * ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT)
+ | (EXT2_FEATURE_COMPAT_DIR_INDEX * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX)
+ );
+ // e2fsprogs-1.41.9 doesn't like EXT2_FEATURE_INCOMPAT_WHITEOUT
+ STORE_LE(sb->s_feature_incompat, EXT2_FEATURE_INCOMPAT_FILETYPE);// | EXT2_FEATURE_INCOMPAT_WHITEOUT;
+ STORE_LE(sb->s_feature_ro_compat, EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER);
+ STORE_LE(sb->s_flags, EXT2_FLAGS_SIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX);
+ generate_uuid(sb->s_uuid);
+ if (ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX) {
+ STORE_LE(sb->s_def_hash_version, EXT2_HASH_HALF_MD4);
+ generate_uuid((uint8_t *)sb->s_hash_seed);
+ }
+ /*
+ * From e2fsprogs: add "jitter" to the superblock's check interval so that we
+ * don't check all the filesystems at the same time. We use a
+ * kludgy hack of using the UUID to derive a random jitter value.
+ */
+ STORE_LE(sb->s_max_mnt_count, EXT2_DFL_MAX_MNT_COUNT
+ + (sb->s_uuid[ARRAY_SIZE(sb->s_uuid)-1] % EXT2_DFL_MAX_MNT_COUNT));
+
+ // write the label, if any
+ if (label) //opts & OPT_L)
+ safe_strncpy((char *)sb->s_volume_name, label, sizeof(sb->s_volume_name));
+
// fill group descriptors
gd = xzalloc(gdtsz * blocksize);
+ buf = xmalloc(blocksize);
sb->s_free_blocks_count = 0;
- for (i = 0, pos = first_data_block, n = nblocks;
+ for (i = 0, pos = first_data_block, n = nblocks - first_data_block;
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;
+ uint32_t fb;
+ STORE_LE(gd[i].bg_block_bitmap, overhead + 0);
+ STORE_LE(gd[i].bg_inode_bitmap, overhead + 1);
+ STORE_LE(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;
+ gd[i].bg_free_inodes_count = inodes_per_group;
+ //STORE_LE(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;
+ STORE_LE(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;
+// // 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) {
+// n -= first_data_block;
+// }
+
+ // mark preallocated blocks as allocated
+ fb = (n < blocks_per_group ? n : blocks_per_group) - overhead;
+//bb_info_msg("ALLOC: [%u][%u][%u]", blocksize, overhead, blocks_per_group - (fb + overhead));
+ allocate(buf, blocksize,
+ overhead,
+ blocks_per_group - (fb + overhead)
+ );
+ // dump block bitmap
+ PUT((uint64_t)(FETCH_LE32(gd[i].bg_block_bitmap)) * blocksize, buf, blocksize);
+ STORE_LE(gd[i].bg_free_blocks_count, fb);
+
+ // mark preallocated inodes as allocated
+ allocate(buf, blocksize,
+ inodes_per_group - gd[i].bg_free_inodes_count,
+ blocks_per_group - inodes_per_group
+ );
+ // dump inode bitmap
+ //PUT((uint64_t)(FETCH_LE32(gd[i].bg_block_bitmap)) * blocksize, buf, blocksize);
+ //but it's right after block bitmap, so we can just:
+ xwrite(fd, buf, blocksize);
+ STORE_LE(gd[i].bg_free_inodes_count, gd[i].bg_free_inodes_count);
+
+ // count overall free blocks
+ sb->s_free_blocks_count += fb;
}
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
+ if (has_super(i)) {
// 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
+ PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
// 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);
+ PUT((uint64_t)(FETCH_LE32(gd[i].bg_inode_table) + n) * blocksize, buf, blocksize);
// prepare directory inode
inode = (struct ext2_inode *)buf;
// 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));
+ STORE_LE(inode->i_block[0], FETCH_LE32(gd[0].bg_inode_table) + itsz);
+ PUT(((uint64_t)FETCH_LE32(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));
+ STORE_LE(inode->i_block[0], inode->i_block[0]+1); // use next block
+ PUT(((uint64_t)FETCH_LE32(gd[0].bg_inode_table) << blocksize_log2) + (EXT2_GOOD_OLD_FIRST_INO-1) * sizeof(*inode), buf, sizeof(*inode));
// dump directories
memset(buf, 0, blocksize);
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);
+ PUT((uint64_t)(FETCH_LE32(gd[0].bg_inode_table) + itsz + 1) * blocksize, buf, blocksize);
// dump root dir block
STORE_LE(dir->inode1, EXT2_ROOT_INO);
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
-// );
+ PUT((uint64_t)(FETCH_LE32(gd[0].bg_inode_table) + itsz + 0) * blocksize, buf, blocksize);
done:
// cleanup
projects / oweals / busybox.git / commitdiff