diff options
| -rw-r--r-- | util-linux/mkfs_ext2.c | 174 | ||||
| -rwxr-xr-x | util-linux/mkfs_ext2_test.sh | 54 |
2 files changed, 153 insertions, 75 deletions
diff --git a/util-linux/mkfs_ext2.c b/util-linux/mkfs_ext2.c index 56203c7..38654ef 100644 --- a/util-linux/mkfs_ext2.c +++ b/util-linux/mkfs_ext2.c @@ -163,17 +163,16 @@ 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, blocksize_log2; + unsigned bs, bpi; + unsigned blocksize, blocksize_log2; unsigned nreserved = 5; - unsigned long long nblocks_ull; + unsigned long long kilobytes; uint32_t nblocks; uint32_t ngroups; - unsigned bytes_per_inode; - uint32_t nblocks_per_group; + uint32_t bytes_per_inode; uint32_t first_data_block; - uint32_t ninodes; uint32_t ninodes_per_group; - uint32_t gdtsz, rgdtsz, itsz; + uint32_t gdtsz, itsz; time_t timestamp; unsigned opts; const char *label; @@ -186,7 +185,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) opt_complementary = "-1:b+:m+:i+"; opts = getopt32(argv, "cl:b:f:i:I:J:G:N:m:o:g:L:M:O:r:E:T:U:jnqvFS", - NULL, &bs, NULL, &bytes_per_inode, NULL, NULL, NULL, NULL, + NULL, &bs, NULL, &bpi, NULL, NULL, NULL, NULL, &nreserved, NULL, NULL, &label, NULL, NULL, NULL, NULL, NULL, NULL); argv += optind; // argv[0] -- device @@ -195,7 +194,8 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) bb_error_msg_and_die("-%c is bad", 'm'); // check the device is a block device - xstat(argv[0], &st); + xmove_fd(xopen(argv[0], O_WRONLY), fd); + fstat(fd, &st); if (!S_ISBLK(st.st_mode) && !(opts & OPT_F)) bb_error_msg_and_die("not a block device"); @@ -206,22 +206,29 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) bb_error_msg_and_die("can't format mounted filesystem"); // open the device, get size in kbytes - xmove_fd(xopen3(argv[0], O_WRONLY | O_CREAT, 0666), fd); if (argv[1]) { - nblocks_ull = xatoull(argv[1]); + kilobytes = xatoull(argv[1]); } else { - nblocks_ull = (uoff_t)xlseek(fd, 0, SEEK_END) / 1024; + kilobytes = (uoff_t)xlseek(fd, 0, SEEK_END) / 1024; } + bytes_per_inode = 16384; + if (kilobytes < 512*1024) + bytes_per_inode = 4096; + if (kilobytes < 3*1024) + bytes_per_inode = 8192; + if (opts & OPT_i) + bytes_per_inode = bpi; + // block size is a multiple of 1024 blocksize = 1024; - if (nblocks_ull >= 512*1024) // mke2fs 1.41.9 compat + if (kilobytes >= 512*1024) // mke2fs 1.41.9 compat blocksize = 4096; if (EXT2_MAX_BLOCK_SIZE > 4096) { - // nblocks_ull >> 22 == size in 4gigabyte chunks. + // kilobytes >> 22 == size in 4gigabyte chunks. // if it is >= 16k gigs, blocksize must be increased. // Try "mke2fs -F image_std $((16 * 1024*1024*1024))" - while ((nblocks_ull >> 22) >= blocksize) + while ((kilobytes >> 22) >= blocksize) blocksize *= 2; } if (opts & OPT_b) @@ -233,13 +240,49 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) bb_error_msg_and_die("blocksize %u is bad", blocksize); } blocksize_log2 = int_log2(blocksize); - nblocks_ull >>= (blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE); + kilobytes >>= (blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE); // nblocks: the total number of blocks in the filesystem - nblocks = nblocks_ull; - if (nblocks != nblocks_ull) + nblocks = kilobytes; + if (nblocks != kilobytes) bb_error_msg_and_die("block count doesn't fit in 32 bits"); 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 @@ -260,15 +303,13 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) 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); + 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 - // 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; + 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_max_mnt_count = EXT2_DFL_MAX_MNT_COUNT; sb->s_checkinterval = 24*60*60 * 180; // 180 days sb->s_errors = EXT2_ERRORS_DEFAULT; sb->s_feature_compat = EXT2_FEATURE_COMPAT_SUPP @@ -289,17 +330,14 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) * 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 += sb->s_uuid[ARRAY_SIZE(sb->s_uuid)-1] % EXT2_DFL_MAX_MNT_COUNT; + 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; - // N.B. a block group can have no more than nblocks_per_group blocks - ngroups = div_roundup(nblocks - first_data_block, nblocks_per_group); - if (0 == ngroups) - bb_error_msg_and_die("ngroups"); gdtsz = div_roundup(ngroups, EXT2_DESC_PER_BLOCK(sb)); /* * From e2fsprogs: Calculate the number of GDT blocks to reserve for online @@ -310,44 +348,28 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) /* We set it at 1024x the current filesystem size, or * the upper block count limit (2^32), whichever is lower. */ -#if ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT - rgdtsz = 0xFFFFFFFF; // maximum block number - if (nblocks < rgdtsz / 1024) - rgdtsz = nblocks * 1024; - rgdtsz = div_roundup(rgdtsz - first_data_block, nblocks_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); - sb->s_reserved_gdt_blocks = rgdtsz; - //bb_info_msg("RSRVD[%u]", n); -#else - rgdtsz = 0; -#endif - - // ninodes is the total number of inodes (files) in the file system - if (!(opts & OPT_i)) { - bytes_per_inode = 16384; - if (nblocks < 512*1024) - bytes_per_inode = 4096; - if (nblocks < 3*1024) - bytes_per_inode = 8192; + if (ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT) { + 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); + gdtsz += rgdtsz; } - 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 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; + + // 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 - ninodes = sb->s_inodes_count = ninodes_per_group * ngroups; + 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; @@ -370,7 +392,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) "%u inodes, %u blocks\n" "%u blocks (%u%%) reserved for the super user\n" "First data block=%u\n" -// "Maximum filesystem blocks=%lu\n" + "Maximum filesystem blocks=%u\n" "%u block groups\n" "%u blocks per group, %u fragments per group\n" "%u inodes per group" @@ -380,16 +402,17 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) , 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 + , gdtsz * EXT2_DESC_PER_BLOCK(sb) * blocks_per_group , ngroups - , nblocks_per_group, nblocks_per_group + , blocks_per_group, blocks_per_group , ninodes_per_group ); { - const char *fmt = "\nSuperblock backups stored on blocks: %u"; + const char *fmt = "\nSuperblock backups stored on blocks:\n" + "\t%u"; pos = first_data_block; for (i = 1; i < ngroups; i++) { - pos += nblocks_per_group; + pos += blocks_per_group; if (has_super(i)) { printf(fmt, (unsigned)pos); fmt = ", %u"; @@ -400,16 +423,16 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) #endif if (opts & OPT_n) - return EXIT_SUCCESS; + goto done; // fill group descriptors - gd = xzalloc((gdtsz + rgdtsz) * blocksize); + gd = xzalloc(gdtsz * blocksize); sb->s_free_blocks_count = 0; for (i = 0, pos = first_data_block, n = nblocks; i < ngroups; - i++, pos += nblocks_per_group, n -= nblocks_per_group + i++, pos += blocks_per_group, n -= blocks_per_group ) { - uint32_t overhead = pos + (has_super(i) ? (1/*sb*/ + gdtsz + rgdtsz) : 0); + 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; @@ -427,7 +450,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) if (ngroups-1 == i) { overhead += first_data_block; } - gd[i].bg_free_blocks_count = (n < nblocks_per_group ? n : nblocks_per_group) - overhead; + 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); @@ -435,22 +458,22 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // 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; - uint32_t start;// = has_super(i) ? (1/*sb*/ + gdtsz + rgdtsz) : 0; + 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 + rgdtsz) * 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 = nblocks_per_group - (start + gd[i].bg_free_blocks_count); + end = blocks_per_group - (start + gd[i].bg_free_blocks_count); // mark preallocated blocks as allocated allocate(buf, blocksize, start, end); @@ -460,7 +483,7 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // mark preallocated inodes as allocated allocate(buf, blocksize, ninodes_per_group - gd[i].bg_free_inodes_count, - 8 * blocksize - ninodes_per_group + blocks_per_group - ninodes_per_group ); // dump inode bitmap //PUT((uint64_t)(pos + overhead + 1) * blocksize, buf, blocksize); @@ -525,10 +548,11 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv) // 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) +// "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); diff --git a/util-linux/mkfs_ext2_test.sh b/util-linux/mkfs_ext2_test.sh new file mode 100755 index 0000000..fe6291f --- /dev/null +++ b/util-linux/mkfs_ext2_test.sh @@ -0,0 +1,54 @@ +#!/bin/sh + +test_mke2fs() { + echo Testing $kilobytes + + >image_std + dd seek=$((kilobytes-1)) bs=1K count=1 </dev/zero of=image_std >/dev/null 2>&1 || exit 1 + /usr/bin/mke2fs -F image_std $kilobytes >image_std.raw_out 2>&1 || return 1 + cat image_std.raw_out \ + | grep -v '^mke2fs ' \ + | grep -v '^Maximum filesystem' \ + | grep -v '^warning: .* blocks unused' \ + | grep -v '^Writing inode tables' \ + | grep -v '^Writing superblocks and filesystem accounting information' \ + | grep -v '^This filesystem will be automatically checked every' \ + | grep -v '^180 days, whichever comes first' \ + | sed 's/block groups/block group/' \ + | sed 's/ *$//' \ + | sed 's/blocks (.*%) reserved/blocks reserved/' \ + | grep -v '^$' \ + >image_std.out + + >image_bb + dd seek=$((kilobytes-1)) bs=1K count=1 </dev/zero of=image_bb >/dev/null 2>&1 || exit 1 + ./busybox mke2fs -F image_bb $kilobytes >image_bb.raw_out 2>&1 || return 1 + cat image_bb.raw_out \ + | grep -v '^mke2fs ' \ + | grep -v '^Maximum filesystem' \ + | grep -v '^warning: .* blocks unused' \ + | grep -v '^Writing inode tables' \ + | grep -v '^Writing superblocks and filesystem accounting information' \ + | grep -v '^This filesystem will be automatically checked every' \ + | grep -v '^180 days, whichever comes first' \ + | sed 's/block groups/block group/' \ + | sed 's/ *$//' \ + | sed 's/blocks (.*%) reserved/blocks reserved/' \ + | grep -v '^$' \ + >image_bb.out + + diff -ua image_bb.out image_std.out >image.out.diff || { + cat image.out.diff + return 1 + } +} + +kilobytes=24908 test_mke2fs +kilobytes=81940 test_mke2fs +kilobytes=98392 test_mke2fs +exit + +while true; do + kilobytes=$(( (RANDOM*RANDOM) % 100000 + 100)) + test_mke2fs || exit 1 +done |