/*
* initialize.c --- initialize a filesystem handle given superblock
* parameters. Used by mke2fs when initializing a filesystem.
*
* Copyright (C) 1994, 1995, 1996 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Library
* General Public License, version 2.
* %End-Header%
*/
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <fcntl.h>
#include <time.h>
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include "ext2_fs.h"
#include "ext2fs.h"
#if defined(__linux__) && defined(EXT2_OS_LINUX)
#define CREATOR_OS EXT2_OS_LINUX
#else
#if defined(__GNU__) && defined(EXT2_OS_HURD)
#define CREATOR_OS EXT2_OS_HURD
#else
#if defined(__FreeBSD__) && defined(EXT2_OS_FREEBSD)
#define CREATOR_OS EXT2_OS_FREEBSD
#else
#if defined(LITES) && defined(EXT2_OS_LITES)
#define CREATOR_OS EXT2_OS_LITES
#else
#define CREATOR_OS EXT2_OS_LINUX /* by default */
#endif /* defined(LITES) && defined(EXT2_OS_LITES) */
#endif /* defined(__FreeBSD__) && defined(EXT2_OS_FREEBSD) */
#endif /* defined(__GNU__) && defined(EXT2_OS_HURD) */
#endif /* defined(__linux__) && defined(EXT2_OS_LINUX) */
/*
* 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.
*/
static unsigned int calc_reserved_gdt_blocks(ext2_filsys fs)
{
struct ext2_super_block *sb = fs->super;
unsigned long bpg = sb->s_blocks_per_group;
unsigned int gdpb = EXT2_DESC_PER_BLOCK(sb);
unsigned long max_blocks = 0xffffffff;
unsigned long rsv_groups;
unsigned int rsv_gdb;
/* We set it at 1024x the current filesystem size, or
* the upper block count limit (2^32), whichever is lower.
*/
if (ext2fs_blocks_count(sb) < max_blocks / 1024)
max_blocks = ext2fs_blocks_count(sb) * 1024;
/*
* ext2fs_div64_ceil() is unnecessary because max_blocks is
* max _GDT_ blocks, which is limited to 32 bits.
*/
rsv_groups = ext2fs_div_ceil(max_blocks - sb->s_first_data_block, bpg);
rsv_gdb = ext2fs_div_ceil(rsv_groups, gdpb) - fs->desc_blocks;
if (rsv_gdb > EXT2_ADDR_PER_BLOCK(sb))
rsv_gdb = EXT2_ADDR_PER_BLOCK(sb);
#ifdef RES_GDT_DEBUG
printf("max_blocks %lu, rsv_groups = %lu, rsv_gdb = %u\n",
max_blocks, rsv_groups, rsv_gdb);
#endif
return rsv_gdb;
}
errcode_t ext2fs_initialize(const char *name, int flags,
struct ext2_super_block *param,
io_manager manager, ext2_filsys *ret_fs)
{
ext2_filsys fs;
errcode_t retval;
struct ext2_super_block *super;
unsigned int rem;
unsigned int overhead = 0;
unsigned int ipg;
dgrp_t i;
blk64_t free_blocks;
blk_t numblocks;
int rsv_gdt;
int csum_flag;
int bigalloc_flag;
int io_flags;
unsigned reserved_inos;
char *buf = 0;
char c;
double reserved_ratio;
if (!param || !ext2fs_blocks_count(param))
return EXT2_ET_INVALID_ARGUMENT;
retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
if (retval)
return retval;
memset(fs, 0, sizeof(struct struct_ext2_filsys));
fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
fs->flags = flags | EXT2_FLAG_RW;
fs->umask = 022;
fs->default_bitmap_type = EXT2FS_BMAP64_RBTREE;
#ifdef WORDS_BIGENDIAN
fs->flags |= EXT2_FLAG_SWAP_BYTES;
#endif
io_flags = IO_FLAG_RW;
if (flags & EXT2_FLAG_EXCLUSIVE)
io_flags |= IO_FLAG_EXCLUSIVE;
if (flags & EXT2_FLAG_DIRECT_IO)
io_flags |= IO_FLAG_DIRECT_IO;
retval = manager->open(name, io_flags, &fs->io);
if (retval)
goto cleanup;
fs->image_io = fs->io;
fs->io->app_data = fs;
retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
if (retval)
goto cleanup;
strcpy(fs->device_name, name);
retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super);
if (retval)
goto cleanup;
fs->super = super;
memset(super, 0, SUPERBLOCK_SIZE);
#define set_field(field, default) (super->field = param->field ? \
param->field : (default))
#define assign_field(field) (super->field = param->field)
super->s_magic = EXT2_SUPER_MAGIC;
super->s_state = EXT2_VALID_FS;
bigalloc_flag = EXT2_HAS_RO_COMPAT_FEATURE(param,
EXT4_FEATURE_RO_COMPAT_BIGALLOC);
assign_field(s_log_block_size);
if (bigalloc_flag) {
set_field(s_log_cluster_size, super->s_log_block_size+4);
if (super->s_log_block_size > super->s_log_cluster_size) {
retval = EXT2_ET_INVALID_ARGUMENT;
goto cleanup;
}
} else
super->s_log_cluster_size = super->s_log_block_size;
set_field(s_first_data_block, super->s_log_cluster_size ? 0 : 1);
set_field(s_max_mnt_count, 0);
set_field(s_errors, EXT2_ERRORS_DEFAULT);
set_field(s_feature_compat, 0);
set_field(s_feature_incompat, 0);
set_field(s_feature_ro_compat, 0);
set_field(s_default_mount_opts, 0);
set_field(s_first_meta_bg, 0);
set_field(s_raid_stride, 0); /* default stride size: 0 */
set_field(s_raid_stripe_width, 0); /* default stripe width: 0 */
set_field(s_log_groups_per_flex, 0);
set_field(s_flags, 0);
if (super->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
retval = EXT2_ET_UNSUPP_FEATURE;
goto cleanup;
}
if (super->s_feature_ro_compat & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP) {
retval = EXT2_ET_RO_UNSUPP_FEATURE;
goto cleanup;
}
set_field(s_rev_level, EXT2_GOOD_OLD_REV);
if (super->s_rev_level >= EXT2_DYNAMIC_REV) {
set_field(s_first_ino, EXT2_GOOD_OLD_FIRST_INO);
set_field(s_inode_size, EXT2_GOOD_OLD_INODE_SIZE);
if (super->s_inode_size >= sizeof(struct ext2_inode_large)) {
int extra_isize = sizeof(struct ext2_inode_large) -
EXT2_GOOD_OLD_INODE_SIZE;
set_field(s_min_extra_isize, extra_isize);
set_field(s_want_extra_isize, extra_isize);
}
} else {
super->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
super->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
}
set_field(s_checkinterval, 0);
super->s_mkfs_time = super->s_lastcheck = fs->now ? fs->now : time(NULL);
super->s_creator_os = CREATOR_OS;
fs->fragsize = fs->blocksize = EXT2_BLOCK_SIZE(super);
fs->cluster_ratio_bits = super->s_log_cluster_size -
super->s_log_block_size;
if (bigalloc_flag) {
unsigned long long bpg;
if (param->s_blocks_per_group &&
param->s_clusters_per_group &&
((param->s_clusters_per_group * EXT2FS_CLUSTER_RATIO(fs)) !=
param->s_blocks_per_group)) {
retval = EXT2_ET_INVALID_ARGUMENT;
goto cleanup;
}
if (param->s_clusters_per_group)
assign_field(s_clusters_per_group);
else if (param->s_blocks_per_group)
super->s_clusters_per_group =
param->s_blocks_per_group /
EXT2FS_CLUSTER_RATIO(fs);
else if (super->s_log_cluster_size + 15 < 32)
super->s_clusters_per_group = fs->blocksize * 8;
else
super->s_clusters_per_group = (fs->blocksize - 1) * 8;
if (super->s_clusters_per_group > EXT2_MAX_CLUSTERS_PER_GROUP(super))
super->s_clusters_per_group = EXT2_MAX_CLUSTERS_PER_GROUP(super);
bpg = EXT2FS_C2B(fs,
(unsigned long long) super->s_clusters_per_group);
if (bpg >= (((unsigned long long) 1) << 32)) {
retval = EXT2_ET_INVALID_ARGUMENT;
goto cleanup;
}
super->s_blocks_per_group = bpg;
} else {
set_field(s_blocks_per_group, fs->blocksize * 8);
if (super->s_blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(super))
super->s_blocks_per_group = EXT2_MAX_BLOCKS_PER_GROUP(super);
super->s_clusters_per_group = super->s_blocks_per_group;
}
ext2fs_blocks_count_set(super, ext2fs_blocks_count(param) &
~((blk64_t) EXT2FS_CLUSTER_MASK(fs)));
ext2fs_r_blocks_count_set(super, ext2fs_r_blocks_count(param));
if (ext2fs_r_blocks_count(super) >= ext2fs_blocks_count(param)) {
retval = EXT2_ET_INVALID_ARGUMENT;
goto cleanup;
}
set_field(s_mmp_update_interval, 0);
/*
* If we're creating an external journal device, we don't need
* to bother with the rest.
*/
if (super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
fs->group_desc_count = 0;
ext2fs_mark_super_dirty(fs);
*ret_fs = fs;
return 0;
}
retry:
fs->group_desc_count = (dgrp_t) ext2fs_div64_ceil(
ext2fs_blocks_count(super) - super->s_first_data_block,
EXT2_BLOCKS_PER_GROUP(super));
if (fs->group_desc_count == 0) {
retval = EXT2_ET_TOOSMALL;
goto cleanup;
}
set_field(s_desc_size,
super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT ?
EXT2_MIN_DESC_SIZE_64BIT : 0);
fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
EXT2_DESC_PER_BLOCK(super));
i = fs->blocksize >= 4096 ? 1 : 4096 / fs->blocksize;
if (super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT &&
(ext2fs_blocks_count(super) / i) > (1ULL << 32))
set_field(s_inodes_count, ~0U);
else
set_field(s_inodes_count, ext2fs_blocks_count(super) / i);
/*
* Make sure we have at least EXT2_FIRST_INO + 1 inodes, so
* that we have enough inodes for the filesystem(!)
*/
if (super->s_inodes_count < EXT2_FIRST_INODE(super)+1)
super->s_inodes_count = EXT2_FIRST_INODE(super)+1;
/*
* There should be at least as many inodes as the user
* requested. Figure out how many inodes per group that
* should be. But make sure that we don't allocate more than
* one bitmap's worth of inodes each group.
*/
ipg = ext2fs_div_ceil(super->s_inodes_count, fs->group_desc_count);
if (ipg > fs->blocksize * 8) {
if (!bigalloc_flag && super->s_blocks_per_group >= 256) {
/* Try again with slightly different parameters */
super->s_blocks_per_group -= 8;
ext2fs_blocks_count_set(super,
ext2fs_blocks_count(param));
super->s_clusters_per_group = super->s_blocks_per_group;
goto retry;
} else {
retval = EXT2_ET_TOO_MANY_INODES;
goto cleanup;
}
}
if (ipg > (unsigned) EXT2_MAX_INODES_PER_GROUP(super))
ipg = EXT2_MAX_INODES_PER_GROUP(super);
ipg_retry:
super->s_inodes_per_group = ipg;
/*
* Make sure the number of inodes per group completely fills
* the inode table blocks in the descriptor. If not, add some
* additional inodes/group. Waste not, want not...
*/
fs->inode_blocks_per_group = (((super->s_inodes_per_group *
EXT2_INODE_SIZE(super)) +
EXT2_BLOCK_SIZE(super) - 1) /
EXT2_BLOCK_SIZE(super));
super->s_inodes_per_group = ((fs->inode_blocks_per_group *
EXT2_BLOCK_SIZE(super)) /
EXT2_INODE_SIZE(super));
/*
* Finally, make sure the number of inodes per group is a
* multiple of 8. This is needed to simplify the bitmap
* splicing code.
*/
if (super->s_inodes_per_group < 8)
super->s_inodes_per_group = 8;
super->s_inodes_per_group &= ~7;
fs->inode_blocks_per_group = (((super->s_inodes_per_group *
EXT2_INODE_SIZE(super)) +
EXT2_BLOCK_SIZE(super) - 1) /
EXT2_BLOCK_SIZE(super));
/*
* adjust inode count to reflect the adjusted inodes_per_group
*/
if ((__u64)super->s_inodes_per_group * fs->group_desc_count > ~0U) {
ipg--;
goto ipg_retry;
}
super->s_inodes_count = super->s_inodes_per_group *
fs->group_desc_count;
super->s_free_inodes_count = super->s_inodes_count;
/*
* check the number of reserved group descriptor table blocks
*/
if (super->s_feature_compat & EXT2_FEATURE_COMPAT_RESIZE_INODE)
rsv_gdt = calc_reserved_gdt_blocks(fs);
else
rsv_gdt = 0;
set_field(s_reserved_gdt_blocks, rsv_gdt);
if (super->s_reserved_gdt_blocks > EXT2_ADDR_PER_BLOCK(super)) {
retval = EXT2_ET_RES_GDT_BLOCKS;
goto cleanup;
}
/*
* Calculate the maximum number of bookkeeping blocks per
* group. It includes the superblock, the block group
* descriptors, the block bitmap, the inode bitmap, the inode
* table, and the reserved gdt blocks.
*/
overhead = (int) (3 + fs->inode_blocks_per_group +
fs->desc_blocks + super->s_reserved_gdt_blocks);
/* This can only happen if the user requested too many inodes */
if (overhead > super->s_blocks_per_group) {
retval = EXT2_ET_TOO_MANY_INODES;
goto cleanup;
}
/*
* See if the last group is big enough to support the
* necessary data structures. If not, we need to get rid of
* it. We need to recalculate the overhead for the last block
* group, since it might or might not have a superblock
* backup.
*/
overhead = (int) (2 + fs->inode_blocks_per_group);
if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
overhead += 1 + fs->desc_blocks + super->s_reserved_gdt_blocks;
rem = ((ext2fs_blocks_count(super) - super->s_first_data_block) %
super->s_blocks_per_group);
if ((fs->group_desc_count == 1) && rem && (rem < overhead)) {
retval = EXT2_ET_TOOSMALL;
goto cleanup;
}
if (rem && (rem < overhead+50)) {
ext2fs_blocks_count_set(super, ext2fs_blocks_count(super) -
rem);
/*
* If blocks count is changed, we need to recalculate
* reserved blocks count not to exceed 50%.
*/
reserved_ratio = 100.0 * ext2fs_r_blocks_count(param) /
ext2fs_blocks_count(param);
ext2fs_r_blocks_count_set(super, reserved_ratio *
ext2fs_blocks_count(super) / 100.0);
goto retry;
}
/*
* At this point we know how big the filesystem will be. So
* we can do any and all allocations that depend on the block
* count.
*/
retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
if (retval)
goto cleanup;
strcpy(buf, "block bitmap for ");
strcat(buf, fs->device_name);
retval = ext2fs_allocate_subcluster_bitmap(fs, buf, &fs->block_map);
if (retval)
goto cleanup;
strcpy(buf, "inode bitmap for ");
strcat(buf, fs->device_name);
retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
if (retval)
goto cleanup;
ext2fs_free_mem(&buf);
retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
&fs->group_desc);
if (retval)
goto cleanup;
memset(fs->group_desc, 0, (size_t) fs->desc_blocks * fs->blocksize);
/*
* Reserve the superblock and group descriptors for each
* group, and fill in the correct group statistics for group.
* Note that although the block bitmap, inode bitmap, and
* inode table have not been allocated (and in fact won't be
* by this routine), they are accounted for nevertheless.
*
* If FLEX_BG meta-data grouping is used, only account for the
* superblock and group descriptors (the inode tables and
* bitmaps will be accounted for when allocated).
*/
free_blocks = 0;
csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
reserved_inos = super->s_first_ino;
for (i = 0; i < fs->group_desc_count; i++) {
/*
* Don't set the BLOCK_UNINIT group for the last group
* because the block bitmap needs to be padded.
*/
if (csum_flag) {
if (i != fs->group_desc_count - 1)
ext2fs_bg_flags_set(fs, i,
EXT2_BG_BLOCK_UNINIT);
ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
numblocks = super->s_inodes_per_group;
if (reserved_inos) {
if (numblocks > reserved_inos) {
numblocks -= reserved_inos;
reserved_inos = 0;
} else {
reserved_inos -= numblocks;
numblocks = 0;
}
}
ext2fs_bg_itable_unused_set(fs, i, numblocks);
}
numblocks = ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
if (fs->super->s_log_groups_per_flex)
numblocks += 2 + fs->inode_blocks_per_group;
free_blocks += numblocks;
ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
ext2fs_bg_free_inodes_count_set(fs, i, fs->super->s_inodes_per_group);
ext2fs_bg_used_dirs_count_set(fs, i, 0);
ext2fs_group_desc_csum_set(fs, i);
}
free_blocks &= ~EXT2FS_CLUSTER_MASK(fs);
ext2fs_free_blocks_count_set(super, free_blocks);
c = (char) 255;
if (((int) c) == -1) {
super->s_flags |= EXT2_FLAGS_SIGNED_HASH;
} else {
super->s_flags |= EXT2_FLAGS_UNSIGNED_HASH;
}
ext2fs_mark_super_dirty(fs);
ext2fs_mark_bb_dirty(fs);
ext2fs_mark_ib_dirty(fs);
io_channel_set_blksize(fs->io, fs->blocksize);
*ret_fs = fs;
return 0;
cleanup:
free(buf);
ext2fs_free(fs);
return retval;
}