From 77da1cae94acbeef90da66bf6530556fe191a6e2 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 18 Oct 2009 16:29:30 +0200 Subject: mkfs_ext2: make it able to create images larger than 4G function old new delta mkfs_ext2_main 1904 2145 +241 has_super 29 23 -6 PUT 52 40 -12 packed_usage 26807 26792 -15 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 1/3 up/down: 241/-33) Total: 208 bytes Signed-off-by: Denys Vlasenko --- util-linux/mkfs_ext2.c | 150 +++++++++++++++++++++++++++++++------------------ 1 file changed, 95 insertions(+), 55 deletions(-) (limited to 'util-linux/mkfs_ext2.c') diff --git a/util-linux/mkfs_ext2.c b/util-linux/mkfs_ext2.c index 8df9f1a66..a990668df 100644 --- a/util-linux/mkfs_ext2.c +++ b/util-linux/mkfs_ext2.c @@ -77,33 +77,18 @@ static void allocate(uint8_t *bitmap, uint32_t blocksize, uint32_t start, uint32 { uint32_t i; memset(bitmap, 0, blocksize); - i = start/8; + 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)))); - i = end/8; - bitmap[blocksize - i - 1] = 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! } -#if 0 -// TODO: get rid of FPU -static bool is_power_of(uint32_t x, uint16_t n) -{ -// return (!(x % n) && is_power_of(x / n, n)); - double z = logf(x)/logf(n); - return (z == (int)z); -} - -static uint32_t has_super(uint32_t x) -{ - return (0 == x || 1 == x || is_power_of(x, 3) || is_power_of(x, 5) || is_power_of(x, 7)); -} - -#else - static uint32_t has_super(uint32_t x) { + // 0, 1 and powers of 3, 5, 7 up to 2^32 limit static const uint32_t supers[] = { 0, 1, 3, 5, 7, 9, 25, 27, 49, 81, 125, 243, 343, 625, 729, 2187, 2401, 3125, 6561, 15625, 16807, 19683, 59049, 78125, @@ -112,16 +97,15 @@ static uint32_t has_super(uint32_t x) 48828125, 129140163, 244140625, 282475249, 387420489, 1162261467, 1220703125, 1977326743, 3486784401/* >2^31 */, }; - const uint32_t *sp = supers + ARRAY_SIZE(supers)-1; + const uint32_t *sp = supers + ARRAY_SIZE(supers); while (1) { + sp--; if (x == *sp) return 1; - if (0 == *sp) + if (x > *sp) return 0; - sp--; } } -#endif /* Standard mke2fs 1.41.9: * Usage: mke2fs [-c|-l filename] [-b block-size] [-f fragment-size] @@ -154,7 +138,7 @@ enum { OPT_T = 1 << 17, OPT_U = 1 << 18, OPT_j = 1 << 19, - OPT_n = 1 << 20, + OPT_n = 1 << 20, // dry run: do not write anything OPT_q = 1 << 21, OPT_v = 1 << 22, OPT_F = 1 << 23, @@ -166,17 +150,16 @@ enum { static void PUT(uint64_t off, void *buf, uint32_t size) { - if (!(option_mask32 & OPT_n)) { - xlseek(fd, off, SEEK_SET); - xwrite(fd, buf, size); - } +// bb_info_msg("PUT[%llu]:[%u]", off, size); + xlseek(fd, off, SEEK_SET); + xwrite(fd, buf, size); } int mkfs_ext2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) { unsigned i, pos, n; - unsigned bs, blocksize; + unsigned bs, blocksize, blocksize_log2; unsigned nreserved = 5; uint32_t nblocks; uint32_t ngroups; @@ -235,7 +218,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // 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: 0/5 dir_index? + // TODO: 3/5 dir_index? // fill the superblock sb = xzalloc(blocksize); @@ -243,13 +226,14 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) 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 = int_log2(blocksize >> EXT2_MIN_BLOCK_LOG_SIZE); + blocksize_log2 = int_log2(blocksize); + 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 first_data_block = sb->s_first_data_block = (EXT2_MIN_BLOCK_SIZE == blocksize); // block and inode bitmaps occupy no more than one block, so maximum number of blocks is // number of bits in one block, i.e. 8*blocksize - nblocks_per_group = sb->s_blocks_per_group = sb->s_frags_per_group = sb->s_inodes_per_group = 8*blocksize; + nblocks_per_group = sb->s_blocks_per_group = sb->s_frags_per_group = sb->s_inodes_per_group = 8 * blocksize; timestamp = time(NULL); sb->s_mkfs_time = sb->s_wtime = sb->s_lastcheck = timestamp; sb->s_state = 1; @@ -266,10 +250,10 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) 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); -#endif + 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 @@ -282,7 +266,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) if (argv[1]) { nblocks = xatou(argv[1]); } else { - nblocks = ((uoff_t)xlseek(fd, 0, SEEK_END)) / blocksize; + nblocks = (uoff_t)xlseek(fd, 0, SEEK_END) >> blocksize_log2; } sb->s_blocks_count = nblocks; @@ -328,17 +312,17 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) if (nblocks < 3*1024) bytes_per_inode = 8192; } - ninodes = nblocks / (bytes_per_inode / blocksize); + 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); if (ninodes_per_group < 16) - ninodes_per_group = 16; // minimum number because the first 10 are reserved + ninodes_per_group = 16; // minimum number because the first EXT2_GOOD_OLD_FIRST_INO-1 are reserved // N.B. a block group can have no more than 8*blocksize = sb->s_inodes_per_group inodes if (ninodes_per_group > sb->s_inodes_per_group) ninodes_per_group = sb->s_inodes_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) / EXT2_INODE_SIZE(sb)); + 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); @@ -352,6 +336,52 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) 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); +*/ + + printf( + "Filesystem label=%s\n" + "OS type: Linux\n" + "Block size=%u (log=%u)\n" + "Fragment size=%u (log=%u)\n" + "%u inodes, %u blocks\n" + "%u blocks (%u%%) reserved for the super user\n" + "First data block=%u\n" +// "Maximum filesystem blocks=%lu\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 + , first_data_block +// , (rgdtsz + gdtsz) * EXT2_DESC_PER_BLOCK(sb) * nblocks_per_group + , ngroups + , nblocks_per_group, nblocks_per_group + , ninodes_per_group + ); + { + const char *fmt = "\nSuperblock backups stored on blocks: %u"; + pos = first_data_block; + for (i = 1; i < ngroups; i++) { + pos += nblocks_per_group; + if (has_super(i)) { + printf(fmt, (unsigned)pos); + fmt = ", %u"; + } + } + } + bb_putchar('\n'); +#endif + + if (opts & OPT_n) + return EXIT_SUCCESS; + // fill group descriptors gd = xzalloc((gdtsz + rgdtsz) * blocksize); sb->s_free_blocks_count = 0; @@ -365,8 +395,8 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) gd[i].bg_inode_table = overhead + 2; overhead = overhead - pos + 1/*bbmp*/ + 1/*ibmp*/ + itsz; gd[i].bg_free_inodes_count = ninodes_per_group; - // N.B. both root and lost+found dirs are within the first block group, thus +2 //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; @@ -383,6 +413,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) 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 += nblocks_per_group) { uint32_t overhead = has_super(i) ? (1/*sb*/ + gdtsz + rgdtsz) : 0; @@ -391,28 +422,30 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // 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 -//bb_info_msg("SUPER@[%d]", pos); // N.B. 1024 byte blocks are special - PUT(blocksize * pos + ((0 == i && 0 == first_data_block) ? 1024 : 0), sb, blocksize); - PUT(blocksize * pos + blocksize, gd, (gdtsz + rgdtsz) * blocksize); + 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 + rgdtsz) * blocksize); } start = overhead + 1/*bbmp*/ + 1/*ibmp*/ + itsz; if (i == 0) - start += 2; // for / and /lost+found + start += 2; // for "/" and "/lost+found" end = nblocks_per_group - (start + gd[i].bg_free_blocks_count); + // mark preallocated blocks as allocated allocate(buf, blocksize, start, end); // dump block bitmap - PUT((pos + overhead) * blocksize, buf, blocksize); + 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, - 8*blocksize - ninodes_per_group + 8 * blocksize - ninodes_per_group ); // dump inode bitmap - PUT((pos + overhead + 1) * blocksize, buf, blocksize); + //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 @@ -421,12 +454,13 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // zero inode tables for (i = 0; i < ngroups; ++i) for (n = 0; n < itsz; ++n) - PUT((gd[i].bg_inode_table + n) * blocksize, buf, blocksize); + 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); - inode->i_mtime = inode->i_atime = timestamp; + 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?! @@ -435,12 +469,12 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // 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(gd[0].bg_inode_table * blocksize + (EXT2_ROOT_INO-1) * sizeof(*inode), buf, sizeof(*inode)); + 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(gd[0].bg_inode_table * blocksize + (EXT2_GOOD_OLD_FIRST_INO-1) * sizeof(*inode), buf, sizeof(*inode)); + 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); @@ -457,7 +491,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) STORE_LE(dir->name_len2, 2); STORE_LE(dir->file_type2, EXT2_FT_DIR); dir->name2[0] = '.'; dir->name2[1] = '.'; - PUT((gd[0].bg_inode_table + itsz + 1) * blocksize, buf, blocksize); + PUT((uint64_t)(gd[0].bg_inode_table + itsz + 1) * blocksize, buf, blocksize); // dump root dir block STORE_LE(dir->inode1, EXT2_ROOT_INO); @@ -467,15 +501,21 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) STORE_LE(dir->name_len3, 10); STORE_LE(dir->file_type3, EXT2_FT_DIR); strcpy(dir->name3, "lost+found"); - PUT((gd[0].bg_inode_table + itsz + 0) * blocksize, buf, blocksize); + 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" +// "%u days, whichever comes first. Use tune2fs -c or -i to override.", +// sb->s_max_mnt_count, sb->s_checkinterval / (3600 * 24) +// ); // cleanup if (ENABLE_FEATURE_CLEAN_UP) { free(buf); free(gd); free(sb); - close(fd); } + xclose(fd); return EXIT_SUCCESS; } -- cgit v1.2.3