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/*
* alloc_tables.c --- Allocate tables for a newly initialized
* filesystem. Used by mke2fs when initializing a filesystem
*
* Copyright (C) 1996 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %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"
/*
* This routine searches for free blocks that can allocate a full
* group of bitmaps or inode tables for a flexbg group. Returns the
* block number with a correct offset were the bitmaps and inode
* tables can be allocated continously and in order.
*/
static blk_t flexbg_offset(ext2_filsys fs, dgrp_t group, blk_t start_blk,
ext2fs_block_bitmap bmap, int offset, int size,
int elem_size)
{
int flexbg, flexbg_size;
blk_t last_blk, first_free = 0;
dgrp_t last_grp;
flexbg_size = 1 << fs->super->s_log_groups_per_flex;
flexbg = group / flexbg_size;
if (size > (int) (fs->super->s_blocks_per_group / 8))
size = (int) fs->super->s_blocks_per_group / 8;
if (offset)
offset -= 1;
/*
* Don't do a long search if the previous block
* search is still valid.
*/
if (start_blk && group % flexbg_size) {
if (ext2fs_test_block_bitmap_range(bmap, start_blk + elem_size,
size))
return start_blk + elem_size;
}
start_blk = ext2fs_group_first_block(fs, flexbg_size * flexbg);
last_grp = group | (flexbg_size - 1);
if (last_grp > fs->group_desc_count)
last_grp = fs->group_desc_count;
last_blk = ext2fs_group_last_block(fs, last_grp);
/* Find the first available block */
if (ext2fs_get_free_blocks(fs, start_blk, last_blk, 1, bmap,
&first_free))
return first_free;
if (ext2fs_get_free_blocks(fs, first_free + offset, last_blk, size,
bmap, &first_free))
return first_free;
return first_free;
}
errcode_t ext2fs_allocate_group_table(ext2_filsys fs, dgrp_t group,
ext2fs_block_bitmap bmap)
{
errcode_t retval;
blk_t group_blk, start_blk, last_blk, new_blk, blk;
dgrp_t last_grp = 0;
int j, rem_grps = 0, flexbg_size = 0;
group_blk = ext2fs_group_first_block(fs, group);
last_blk = ext2fs_group_last_block(fs, group);
if (!bmap)
bmap = fs->block_map;
if (EXT2_HAS_INCOMPAT_FEATURE(fs->super,
EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
fs->super->s_log_groups_per_flex) {
flexbg_size = 1 << fs->super->s_log_groups_per_flex;
last_grp = group | (flexbg_size - 1);
rem_grps = last_grp - group;
if (last_grp > fs->group_desc_count)
last_grp = fs->group_desc_count;
}
/*
* Allocate the block and inode bitmaps, if necessary
*/
if (fs->stride) {
retval = ext2fs_get_free_blocks(fs, group_blk, last_blk,
1, bmap, &start_blk);
if (retval)
return retval;
start_blk += fs->inode_blocks_per_group;
start_blk += ((fs->stride * group) %
(last_blk - start_blk + 1));
if (start_blk >= last_blk)
start_blk = group_blk;
} else
start_blk = group_blk;
if (flexbg_size) {
blk_t prev_block = 0;
if (group && fs->group_desc[group-1].bg_block_bitmap)
prev_block = fs->group_desc[group-1].bg_block_bitmap;
start_blk = flexbg_offset(fs, group, prev_block, bmap,
0, rem_grps, 1);
last_blk = ext2fs_group_last_block(fs, last_grp);
}
if (!fs->group_desc[group].bg_block_bitmap) {
retval = ext2fs_get_free_blocks(fs, start_blk, last_blk,
1, bmap, &new_blk);
if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
retval = ext2fs_get_free_blocks(fs, group_blk,
last_blk, 1, bmap, &new_blk);
if (retval)
return retval;
ext2fs_mark_block_bitmap(bmap, new_blk);
fs->group_desc[group].bg_block_bitmap = new_blk;
if (flexbg_size) {
dgrp_t gr = ext2fs_group_of_blk(fs, new_blk);
fs->group_desc[gr].bg_free_blocks_count--;
fs->super->s_free_blocks_count--;
fs->group_desc[gr].bg_flags &= ~EXT2_BG_BLOCK_UNINIT;
ext2fs_group_desc_csum_set(fs, gr);
}
}
if (flexbg_size) {
blk_t prev_block = 0;
if (group && fs->group_desc[group-1].bg_inode_bitmap)
prev_block = fs->group_desc[group-1].bg_inode_bitmap;
start_blk = flexbg_offset(fs, group, prev_block, bmap,
flexbg_size, rem_grps, 1);
last_blk = ext2fs_group_last_block(fs, last_grp);
}
if (!fs->group_desc[group].bg_inode_bitmap) {
retval = ext2fs_get_free_blocks(fs, start_blk, last_blk,
1, bmap, &new_blk);
if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
retval = ext2fs_get_free_blocks(fs, group_blk,
last_blk, 1, bmap, &new_blk);
if (retval)
return retval;
ext2fs_mark_block_bitmap(bmap, new_blk);
fs->group_desc[group].bg_inode_bitmap = new_blk;
if (flexbg_size) {
dgrp_t gr = ext2fs_group_of_blk(fs, new_blk);
fs->group_desc[gr].bg_free_blocks_count--;
fs->super->s_free_blocks_count--;
fs->group_desc[gr].bg_flags &= ~EXT2_BG_BLOCK_UNINIT;
ext2fs_group_desc_csum_set(fs, gr);
}
}
/*
* Allocate the inode table
*/
if (flexbg_size) {
int prev_block = 0;
if (group && fs->group_desc[group-1].bg_inode_table)
prev_block = fs->group_desc[group-1].bg_inode_table;
group_blk = flexbg_offset(fs, group, prev_block, bmap,
flexbg_size * 2,
fs->inode_blocks_per_group *
rem_grps,
fs->inode_blocks_per_group);
last_blk = ext2fs_group_last_block(fs, last_grp);
}
if (!fs->group_desc[group].bg_inode_table) {
retval = ext2fs_get_free_blocks(fs, group_blk, last_blk,
fs->inode_blocks_per_group,
bmap, &new_blk);
if (retval)
return retval;
for (j=0, blk = new_blk;
j < fs->inode_blocks_per_group;
j++, blk++) {
ext2fs_mark_block_bitmap(bmap, blk);
if (flexbg_size) {
dgrp_t gr = ext2fs_group_of_blk(fs, blk);
fs->group_desc[gr].bg_free_blocks_count--;
fs->super->s_free_blocks_count--;
fs->group_desc[gr].bg_flags &= ~EXT2_BG_BLOCK_UNINIT;
ext2fs_group_desc_csum_set(fs, gr);
}
}
fs->group_desc[group].bg_inode_table = new_blk;
}
ext2fs_group_desc_csum_set(fs, group);
return 0;
}
errcode_t ext2fs_allocate_tables(ext2_filsys fs)
{
errcode_t retval;
dgrp_t i;
for (i = 0; i < fs->group_desc_count; i++) {
retval = ext2fs_allocate_group_table(fs, i, fs->block_map);
if (retval)
return retval;
}
return 0;
}
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