1 /* vi: set sw=4 ts=4: */
3 * mkfs_ext2: utility to create EXT2 filesystem
4 * inspired by genext2fs
6 * Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
8 * Licensed under GPLv2, see file LICENSE in this tarball for details.
12 #include <linux/ext2_fs.h>
13 #include "volume_id/volume_id_internal.h"
15 #define ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
16 #define ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX 1
19 #define s_reserved_gdt_blocks s_padding1
20 #define s_mkfs_time s_reserved[0]
21 #define s_flags s_reserved[22]
23 #define EXT2_HASH_HALF_MD4 1
24 #define EXT2_FLAGS_SIGNED_HASH 0x0001
25 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002
28 char BUG_wrong_field_size(void);
29 #define STORE_LE(field, value) \
31 if (sizeof(field) == 4) \
32 field = cpu_to_le32(value); \
33 else if (sizeof(field) == 2) \
34 field = cpu_to_le16(value); \
35 else if (sizeof(field) == 1) \
38 BUG_wrong_field_size(); \
41 #define FETCH_LE32(field) \
42 (sizeof(field) == 4 ? cpu_to_le32(field) : BUG_wrong_field_size())
44 // All fields are little-endian
63 static unsigned int_log2(unsigned arg)
66 while ((arg >>= 1) != 0)
71 // taken from mkfs_minix.c. libbb candidate?
72 // "uint32_t size", since we never use it for anything >32 bits
73 static uint32_t div_roundup(uint32_t size, uint32_t n)
76 uint32_t res = size / n;
82 static void allocate(uint8_t *bitmap, uint32_t blocksize, uint32_t start, uint32_t end)
86 //bb_info_msg("ALLOC: [%u][%u][%u]: [%u-%u]:=[%x],[%x]", blocksize, start, end, start/8, blocksize - end/8 - 1, (1 << (start & 7)) - 1, (uint8_t)(0xFF00 >> (end & 7)));
87 memset(bitmap, 0, blocksize);
89 memset(bitmap, 0xFF, i);
90 bitmap[i] = (1 << (start & 7)) - 1; //0..7 => 00000000..01111111
92 bitmap[blocksize - i - 1] |= 0x7F00 >> (end & 7); //0..7 => 00000000..11111110
93 memset(bitmap + blocksize - i, 0xFF, i); // N.B. no overflow here!
96 static uint32_t has_super(uint32_t x)
98 // 0, 1 and powers of 3, 5, 7 up to 2^32 limit
99 static const uint32_t supers[] = {
100 0, 1, 3, 5, 7, 9, 25, 27, 49, 81, 125, 243, 343, 625, 729,
101 2187, 2401, 3125, 6561, 15625, 16807, 19683, 59049, 78125,
102 117649, 177147, 390625, 531441, 823543, 1594323, 1953125,
103 4782969, 5764801, 9765625, 14348907, 40353607, 43046721,
104 48828125, 129140163, 244140625, 282475249, 387420489,
105 1162261467, 1220703125, 1977326743, 3486784401/* >2^31 */,
107 const uint32_t *sp = supers + ARRAY_SIZE(supers);
117 #define fd 3 /* predefined output descriptor */
119 static void PUT(uint64_t off, void *buf, uint32_t size)
121 // bb_info_msg("PUT[%llu]:[%u]", off, size);
122 xlseek(fd, off, SEEK_SET);
123 xwrite(fd, buf, size);
126 // 128 and 256-byte inodes:
127 // 128-byte inode is described by struct ext2_inode.
128 // 256-byte one just has these fields appended:
129 // __u16 i_extra_isize;
131 // __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
132 // __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */
133 // __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
134 // __u32 i_crtime; /* File creation time */
135 // __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/
136 // __u32 i_version_hi; /* high 32 bits for 64-bit version */
137 // the rest is padding.
139 // linux/ext2_fs.h has "#define i_size_high i_dir_acl" which suggests that even
140 // 128-byte inode is capable of describing large files (i_dir_acl is meaningful
141 // only for directories, which never need i_size_high).
143 // Standard mke2fs creates a filesystem with 256-byte inodes if it is
144 // bigger than 0.5GB. So far, we do not do this.
146 // Standard mke2fs 1.41.9:
147 // Usage: mke2fs [-c|-l filename] [-b block-size] [-f fragment-size]
148 // [-i bytes-per-inode] [-I inode-size] [-J journal-options]
149 // [-G meta group size] [-N number-of-inodes]
150 // [-m reserved-blocks-percentage] [-o creator-os]
151 // [-g blocks-per-group] [-L volume-label] [-M last-mounted-directory]
152 // [-O feature[,...]] [-r fs-revision] [-E extended-option[,...]]
153 // [-T fs-type] [-U UUID] [-jnqvFSV] device [blocks-count]
155 // Options not commented below are taken but silently ignored:
159 OPT_b = 1 << 2, // block size, in bytes
161 OPT_i = 1 << 4, // bytes per inode
166 OPT_m = 1 << 9, // percentage of blocks reserved for superuser
169 OPT_L = 1 << 12, // label
177 OPT_n = 1 << 20, // dry run: do not write anything
182 //OPT_V = 1 << 25, // -V version. bbox applets don't support that
185 int mkfs_ext2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
186 int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
190 unsigned blocksize, blocksize_log2;
191 unsigned reserved_percent = 5;
192 unsigned long long kilobytes;
193 uint32_t nblocks, nblocks_full;
196 uint32_t bytes_per_inode;
197 uint32_t first_block;
198 uint32_t inodes_per_group;
199 uint32_t group_desc_blocks;
200 uint32_t inode_table_blocks;
201 uint32_t lost_and_found_blocks;
204 const char *label = "";
206 struct ext2_super_block *sb; // superblock
207 struct ext2_group_desc *gd; // group descriptors
208 struct ext2_inode *inode;
209 struct ext2_dir *dir;
212 opt_complementary = "-1:b+:m+:i+";
213 opts = getopt32(argv, "cl:b:f:i:I:J:G:N:m:o:g:L:M:O:r:E:T:U:jnqvFS",
214 NULL, &bs, NULL, &bpi, NULL, NULL, NULL, NULL,
215 &reserved_percent, NULL, NULL, &label, NULL, NULL, NULL, NULL, NULL, NULL);
216 argv += optind; // argv[0] -- device
218 // check the device is a block device
219 xmove_fd(xopen(argv[0], O_WRONLY), fd);
221 if (!S_ISBLK(st.st_mode) && !(opts & OPT_F))
222 bb_error_msg_and_die("not a block device");
224 // check if it is mounted
225 // N.B. what if we format a file? find_mount_point will return false negative since
226 // it is loop block device which mounted!
227 if (find_mount_point(argv[0], 0))
228 bb_error_msg_and_die("can't format mounted filesystem");
230 // open the device, get size in kbytes
232 kilobytes = xatoull(argv[1]);
233 // seek past end fails on block devices but works on files
234 if (lseek(fd, kilobytes * 1024 - 1, SEEK_SET) != (off_t)-1) {
235 xwrite(fd, "", 1); // file grows if needed
238 // bb_error_msg("warning, block device is smaller");
241 kilobytes = (uoff_t)xlseek(fd, 0, SEEK_END) / 1024;
244 bytes_per_inode = 16384;
245 if (kilobytes < 512*1024)
246 bytes_per_inode = 4096;
247 if (kilobytes < 3*1024)
248 bytes_per_inode = 8192;
250 bytes_per_inode = bpi;
252 // Determine block size
253 // block size is a multiple of 1024
255 if (kilobytes >= 512*1024) // mke2fs 1.41.9 compat
257 if (EXT2_MAX_BLOCK_SIZE > 4096) {
258 // kilobytes >> 22 == size in 4gigabyte chunks.
259 // if size >= 16k gigs, blocksize must be increased.
260 // Try "mke2fs -F image $((16 * 1024*1024*1024))"
261 while ((kilobytes >> 22) >= blocksize)
266 if (blocksize < EXT2_MIN_BLOCK_SIZE
267 || blocksize > EXT2_MAX_BLOCK_SIZE
268 || (blocksize & (blocksize - 1)) // not power of 2
270 bb_error_msg_and_die("blocksize %u is bad", blocksize);
272 if ((int32_t)bytes_per_inode < blocksize)
273 bb_error_msg_and_die("-%c is bad", 'i');
274 // number of bits in one block, i.e. 8*blocksize
275 #define blocks_per_group (8 * blocksize)
276 first_block = (EXT2_MIN_BLOCK_SIZE == blocksize);
277 blocksize_log2 = int_log2(blocksize);
279 // Determine number of blocks
280 kilobytes >>= (blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
282 if (nblocks != kilobytes)
283 bb_error_msg_and_die("block count doesn't fit in 32 bits");
284 #define kilobytes kilobytes_unused_after_this
285 // Experimentally, standard mke2fs won't work on images smaller than 60k
287 bb_error_msg_and_die("need >= 60 blocks");
289 // How many reserved blocks?
290 if (reserved_percent > 50)
291 bb_error_msg_and_die("-%c is bad", 'm');
292 nreserved = (uint64_t)nblocks * reserved_percent / 100;
294 // N.B. killing e2fsprogs feature! Unused blocks don't account in calculations
295 nblocks_full = nblocks;
297 // If last block group is too small, nblocks may be decreased in order
298 // to discard it, and control returns here to recalculate some
300 // Note: blocksize and bytes_per_inode are never recalculated.
302 // N.B. a block group can have no more than blocks_per_group blocks
303 ngroups = div_roundup(nblocks - first_block, blocks_per_group);
305 group_desc_blocks = div_roundup(ngroups, blocksize / sizeof(*gd));
306 // TODO: reserved blocks must be marked as such in the bitmaps,
307 // or resulting filesystem is corrupt
308 if (ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT) {
310 * From e2fsprogs: Calculate the number of GDT blocks to reserve for online
312 * The absolute maximum number of GDT blocks we can reserve is determined by
313 * the number of block pointers that can fit into a single block.
314 * We set it at 1024x the current filesystem size, or
315 * the upper block count limit (2^32), whichever is lower.
317 uint32_t reserved_group_desc_blocks = 0xFFFFFFFF; // maximum block number
318 if (nblocks < reserved_group_desc_blocks / 1024)
319 reserved_group_desc_blocks = nblocks * 1024;
320 reserved_group_desc_blocks = div_roundup(reserved_group_desc_blocks - first_block, blocks_per_group);
321 reserved_group_desc_blocks = div_roundup(reserved_group_desc_blocks, blocksize / sizeof(*gd)) - group_desc_blocks;
322 if (reserved_group_desc_blocks > blocksize / sizeof(uint32_t))
323 reserved_group_desc_blocks = blocksize / sizeof(uint32_t);
324 //TODO: STORE_LE(sb->s_reserved_gdt_blocks, reserved_group_desc_blocks);
325 group_desc_blocks += reserved_group_desc_blocks;
329 // N.B. e2fsprogs does as follows!
330 uint32_t overhead, remainder;
331 // ninodes is the max number of inodes in this filesystem
332 uint32_t ninodes = ((uint64_t) nblocks_full * blocksize) / bytes_per_inode;
333 if (ninodes < EXT2_GOOD_OLD_FIRST_INO+1)
334 ninodes = EXT2_GOOD_OLD_FIRST_INO+1;
335 inodes_per_group = div_roundup(ninodes, ngroups);
336 // minimum number because the first EXT2_GOOD_OLD_FIRST_INO-1 are reserved
337 if (inodes_per_group < 16)
338 inodes_per_group = 16;
339 // a block group can't have more inodes than blocks
340 if (inodes_per_group > blocks_per_group)
341 inodes_per_group = blocks_per_group;
342 // adjust inodes per group so they completely fill the inode table blocks in the descriptor
343 //incompatibility on images >= 0.5GB:
344 //difference in sizeof(*inode) sometimes
345 //results in slightly bigger inodes_per_group here
346 //compared to standard mke2fs:
347 inodes_per_group = (div_roundup(inodes_per_group * sizeof(*inode), blocksize) * blocksize) / sizeof(*inode);
348 // make sure the number of inodes per group is a multiple of 8
349 inodes_per_group &= ~7;
350 inode_table_blocks = div_roundup(inodes_per_group * sizeof(*inode), blocksize);
352 // to be useful, lost+found should occupy at least 2 blocks (but not exceeding 16*1024 bytes),
353 // and at most EXT2_NDIR_BLOCKS. So reserve these blocks right now
354 /* Or e2fsprogs comment verbatim (what does it mean?):
355 * Ensure that lost+found is at least 2 blocks, so we always
356 * test large empty blocks for big-block filesystems. */
357 lost_and_found_blocks = MIN(EXT2_NDIR_BLOCKS, 16 >> (blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE));
359 // the last group needs more attention: isn't it too small for possible overhead?
360 overhead = (has_super(ngroups - 1) ? (1/*sb*/ + group_desc_blocks) : 0) + 1/*bbmp*/ + 1/*ibmp*/ + inode_table_blocks;
361 remainder = (nblocks - first_block) % blocks_per_group;
362 ////can't happen, nblocks >= 60 guarantees this
363 ////if ((1 == ngroups)
365 //// && (remainder < overhead + 1/* "/" */ + lost_and_found_blocks)
367 //// bb_error_msg_and_die("way small device");
370 // Standard mke2fs uses 50. Looks like a bug in our calculation
371 // of "remainder" or "overhead" - we don't match standard mke2fs
372 // when we transition from one group to two groups
373 // (a bit after 8M image size), but it works for two->three groups
374 // transition (at 16M).
375 if (remainder && (remainder < overhead + 50)) {
376 //bb_info_msg("CHOP[%u]", remainder);
377 nblocks -= remainder;
382 if (nblocks_full - nblocks)
383 printf("warning: %u blocks unused\n\n", nblocks_full - nblocks);
385 "Filesystem label=%s\n"
387 "Block size=%u (log=%u)\n"
388 "Fragment size=%u (log=%u)\n"
389 "%u inodes, %u blocks\n"
390 "%u blocks (%u%%) reserved for the super user\n"
391 "First data block=%u\n"
392 "Maximum filesystem blocks=%u\n"
394 "%u blocks per group, %u fragments per group\n"
395 "%u inodes per group"
397 , blocksize, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE
398 , blocksize, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE
399 , inodes_per_group * ngroups, nblocks
400 , nreserved, reserved_percent
402 , group_desc_blocks * (blocksize / sizeof(*gd)) * blocks_per_group
404 , blocks_per_group, blocks_per_group
408 const char *fmt = "\nSuperblock backups stored on blocks:\n"
411 for (i = 1; i < ngroups; i++) {
412 pos += blocks_per_group;
414 printf(fmt, (unsigned)pos);
422 if (ENABLE_FEATURE_CLEAN_UP)
427 // TODO: 3/5 refuse if mounted
428 // TODO: 4/5 compat options
429 // TODO: 1/5 sanity checks
430 // TODO: 0/5 more verbose error messages
431 // TODO: 4/5 bigendianness: recheck, wait for ARM reporters
432 // TODO: 2/5 reserved GDT: how to mark but not allocate?
433 // TODO: 3/5 dir_index?
435 // fill the superblock
437 STORE_LE(sb->s_rev_level, 1); // revision 1 filesystem
438 STORE_LE(sb->s_magic, EXT2_SUPER_MAGIC);
440 //on images > 0.5GB, standard mke2fs uses 256 byte inodes.
441 //we always use 128 byte ones:
442 STORE_LE(sb->s_inode_size, sizeof(*inode));
443 STORE_LE(sb->s_first_ino, EXT2_GOOD_OLD_FIRST_INO);
444 STORE_LE(sb->s_log_block_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
445 STORE_LE(sb->s_log_frag_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
446 // first 1024 bytes of the device are for boot record. If block size is 1024 bytes, then
447 // the first block is 1, otherwise 0
448 STORE_LE(sb->s_first_data_block, first_block);
449 // block and inode bitmaps occupy no more than one block, so maximum number of blocks is
450 STORE_LE(sb->s_blocks_per_group, blocks_per_group);
451 STORE_LE(sb->s_frags_per_group, blocks_per_group);
453 STORE_LE(sb->s_blocks_count, nblocks);
454 // reserve blocks for superuser
455 STORE_LE(sb->s_r_blocks_count, nreserved);
457 STORE_LE(sb->s_inodes_per_group, inodes_per_group);
458 STORE_LE(sb->s_inodes_count, inodes_per_group * ngroups);
459 STORE_LE(sb->s_free_inodes_count, inodes_per_group * ngroups - EXT2_GOOD_OLD_FIRST_INO);
461 timestamp = time(NULL);
462 STORE_LE(sb->s_mkfs_time, timestamp);
463 STORE_LE(sb->s_wtime, timestamp);
464 STORE_LE(sb->s_lastcheck, timestamp);
465 // misc. Values are chosen to match mke2fs 1.41.9
466 STORE_LE(sb->s_state, 1); // TODO: what's 1?
467 STORE_LE(sb->s_creator_os, EXT2_OS_LINUX);
468 STORE_LE(sb->s_checkinterval, 24*60*60 * 180); // 180 days
469 STORE_LE(sb->s_errors, EXT2_ERRORS_DEFAULT);
470 // mke2fs 1.41.9 also sets EXT3_FEATURE_COMPAT_RESIZE_INODE
471 // and if >= 0.5GB, EXT3_FEATURE_RO_COMPAT_LARGE_FILE.
472 // we use values which match "mke2fs -O ^resize_inode":
473 // in this case 1.41.9 never sets EXT3_FEATURE_RO_COMPAT_LARGE_FILE.
474 STORE_LE(sb->s_feature_compat, EXT2_FEATURE_COMPAT_SUPP
475 | (EXT2_FEATURE_COMPAT_RESIZE_INO * ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT)
476 | (EXT2_FEATURE_COMPAT_DIR_INDEX * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX)
478 STORE_LE(sb->s_feature_incompat, EXT2_FEATURE_INCOMPAT_FILETYPE);
479 STORE_LE(sb->s_feature_ro_compat, EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER);
480 STORE_LE(sb->s_flags, EXT2_FLAGS_UNSIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX);
481 generate_uuid(sb->s_uuid);
482 if (ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX) {
483 STORE_LE(sb->s_def_hash_version, EXT2_HASH_HALF_MD4);
484 generate_uuid((uint8_t *)sb->s_hash_seed);
487 * From e2fsprogs: add "jitter" to the superblock's check interval so that we
488 * don't check all the filesystems at the same time. We use a
489 * kludgy hack of using the UUID to derive a random jitter value.
491 STORE_LE(sb->s_max_mnt_count,
492 EXT2_DFL_MAX_MNT_COUNT
493 + (sb->s_uuid[ARRAY_SIZE(sb->s_uuid)-1] % EXT2_DFL_MAX_MNT_COUNT));
496 safe_strncpy((char *)sb->s_volume_name, label, sizeof(sb->s_volume_name));
498 // calculate filesystem skeleton structures
499 gd = xzalloc(group_desc_blocks * blocksize);
500 buf = xmalloc(blocksize);
501 sb->s_free_blocks_count = 0;
502 for (i = 0, pos = first_block, n = nblocks - first_block;
504 i++, pos += blocks_per_group, n -= blocks_per_group
506 uint32_t overhead = pos + (has_super(i) ? (1/*sb*/ + group_desc_blocks) : 0);
507 uint32_t free_blocks;
508 // fill group descriptors
509 STORE_LE(gd[i].bg_block_bitmap, overhead + 0);
510 STORE_LE(gd[i].bg_inode_bitmap, overhead + 1);
511 STORE_LE(gd[i].bg_inode_table, overhead + 2);
512 overhead = overhead - pos + 1/*bbmp*/ + 1/*ibmp*/ + inode_table_blocks;
513 gd[i].bg_free_inodes_count = inodes_per_group;
514 //STORE_LE(gd[i].bg_used_dirs_count, 0);
515 // N.B. both "/" and "/lost+found" are within the first block group
516 // "/" occupies 1 block, "/lost+found" occupies lost_and_found_blocks...
518 // ... thus increased overhead for the first block group ...
519 overhead += 1 + lost_and_found_blocks;
520 // ... and 2 used directories
521 STORE_LE(gd[i].bg_used_dirs_count, 2);
522 // well known reserved inodes belong to the first block too
523 gd[i].bg_free_inodes_count -= EXT2_GOOD_OLD_FIRST_INO;
526 // cache free block count of the group
527 free_blocks = (n < blocks_per_group ? n : blocks_per_group) - overhead;
529 // mark preallocated blocks as allocated
530 //bb_info_msg("ALLOC: [%u][%u][%u]", blocksize, overhead, blocks_per_group - (free_blocks + overhead));
531 allocate(buf, blocksize,
532 // reserve "overhead" blocks
534 // mark unused trailing blocks
535 blocks_per_group - (free_blocks + overhead)
538 PUT((uint64_t)(FETCH_LE32(gd[i].bg_block_bitmap)) * blocksize, buf, blocksize);
539 STORE_LE(gd[i].bg_free_blocks_count, free_blocks);
541 // mark preallocated inodes as allocated
542 allocate(buf, blocksize,
543 // mark reserved inodes
544 inodes_per_group - gd[i].bg_free_inodes_count,
545 // mark unused trailing inodes
546 blocks_per_group - inodes_per_group
549 //PUT((uint64_t)(FETCH_LE32(gd[i].bg_block_bitmap)) * blocksize, buf, blocksize);
550 //but it's right after block bitmap, so we can just:
551 xwrite(fd, buf, blocksize);
552 STORE_LE(gd[i].bg_free_inodes_count, gd[i].bg_free_inodes_count);
554 // count overall free blocks
555 sb->s_free_blocks_count += free_blocks;
557 STORE_LE(sb->s_free_blocks_count, sb->s_free_blocks_count);
559 // dump filesystem skeleton structures
560 // printf("Writing superblocks and filesystem accounting information: ");
561 for (i = 0, pos = first_block; i < ngroups; i++, pos += blocks_per_group) {
562 // dump superblock and group descriptors and their backups
564 // N.B. 1024 byte blocks are special
565 PUT(((uint64_t)pos * blocksize) + ((0 == i && 1024 != blocksize) ? 1024 : 0),
567 PUT(((uint64_t)pos * blocksize) + blocksize,
568 gd, group_desc_blocks * blocksize);
573 memset(buf, 0, blocksize);
574 PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
576 for (i = 0; i < ngroups; ++i)
577 for (n = 0; n < inode_table_blocks; ++n)
578 PUT((uint64_t)(FETCH_LE32(gd[i].bg_inode_table) + n) * blocksize,
581 // prepare directory inode
582 inode = (struct ext2_inode *)buf;
583 STORE_LE(inode->i_mode, S_IFDIR | S_IRWXU | S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
584 STORE_LE(inode->i_mtime, timestamp);
585 STORE_LE(inode->i_atime, timestamp);
586 STORE_LE(inode->i_ctime, timestamp);
587 STORE_LE(inode->i_size, blocksize);
588 // inode->i_blocks stores the number of 512 byte data blocks
589 // (512, because it goes directly to struct stat without scaling)
590 STORE_LE(inode->i_blocks, blocksize / 512);
592 // dump root dir inode
593 STORE_LE(inode->i_links_count, 3); // "/.", "/..", "/lost+found/.." point to this inode
594 STORE_LE(inode->i_block[0], FETCH_LE32(gd[0].bg_inode_table) + inode_table_blocks);
595 PUT(((uint64_t)FETCH_LE32(gd[0].bg_inode_table) * blocksize) + (EXT2_ROOT_INO-1) * sizeof(*inode),
596 buf, sizeof(*inode));
598 // dump lost+found dir inode
599 STORE_LE(inode->i_links_count, 2); // both "/lost+found" and "/lost+found/." point to this inode
600 STORE_LE(inode->i_size, lost_and_found_blocks * blocksize);
601 STORE_LE(inode->i_blocks, (lost_and_found_blocks * blocksize) / 512);
602 n = FETCH_LE32(inode->i_block[0]) + 1;
603 for (i = 0; i < lost_and_found_blocks; ++i)
604 STORE_LE(inode->i_block[i], i + n); // use next block
605 //bb_info_msg("LAST BLOCK USED[%u]", i + n);
606 PUT(((uint64_t)FETCH_LE32(gd[0].bg_inode_table) * blocksize) + (EXT2_GOOD_OLD_FIRST_INO-1) * sizeof(*inode),
607 buf, sizeof(*inode));
610 memset(buf, 0, blocksize);
611 dir = (struct ext2_dir *)buf;
613 // dump 2nd+ blocks of "/lost+found"
614 STORE_LE(dir->rec_len1, blocksize); // e2fsck 1.41.4 compat (1.41.9 does not need this)
615 for (i = 1; i < lost_and_found_blocks; ++i)
616 PUT((uint64_t)(FETCH_LE32(gd[0].bg_inode_table) + inode_table_blocks + 1+i) * blocksize,
619 // dump 1st block of "/lost+found"
620 STORE_LE(dir->inode1, EXT2_GOOD_OLD_FIRST_INO);
621 STORE_LE(dir->rec_len1, 12);
622 STORE_LE(dir->name_len1, 1);
623 STORE_LE(dir->file_type1, EXT2_FT_DIR);
625 STORE_LE(dir->inode2, EXT2_ROOT_INO);
626 STORE_LE(dir->rec_len2, blocksize - 12);
627 STORE_LE(dir->name_len2, 2);
628 STORE_LE(dir->file_type2, EXT2_FT_DIR);
629 dir->name2[0] = '.'; dir->name2[1] = '.';
630 PUT((uint64_t)(FETCH_LE32(gd[0].bg_inode_table) + inode_table_blocks + 1) * blocksize, buf, blocksize);
632 // dump root dir block
633 STORE_LE(dir->inode1, EXT2_ROOT_INO);
634 STORE_LE(dir->rec_len2, 12);
635 STORE_LE(dir->inode3, EXT2_GOOD_OLD_FIRST_INO);
636 STORE_LE(dir->rec_len3, blocksize - 12 - 12);
637 STORE_LE(dir->name_len3, 10);
638 STORE_LE(dir->file_type3, EXT2_FT_DIR);
639 strcpy(dir->name3, "lost+found");
640 PUT((uint64_t)(FETCH_LE32(gd[0].bg_inode_table) + inode_table_blocks + 0) * blocksize, buf, blocksize);
643 if (ENABLE_FEATURE_CLEAN_UP) {