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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 Library
* General Public License, version 2.
* %End-Header%
*/
#include "config.h"
#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"
#include "ext2fsP.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 continuously and in order.
*/
static blk64_t flexbg_offset(ext2_filsys fs, dgrp_t group, blk64_t start_blk,
ext2fs_block_bitmap bmap, int rem_grp,
int elem_size)
{
int flexbg, flexbg_size, size;
blk64_t last_blk, first_free = 0;
dgrp_t last_grp;
flexbg_size = 1 << fs->super->s_log_groups_per_flex;
flexbg = group / flexbg_size;
size = rem_grp * elem_size;
if (size > (int) (fs->super->s_blocks_per_group / 4))
size = (int) fs->super->s_blocks_per_group / 4;
/*
* Don't do a long search if the previous block search is still valid,
* but skip minor obstructions such as group descriptor backups.
*/
if (start_blk && start_blk < ext2fs_blocks_count(fs->super) &&
ext2fs_get_free_blocks2(fs, start_blk, start_blk + size, elem_size,
bmap, &first_free) == 0)
return first_free;
start_blk = ext2fs_group_first_block2(fs, flexbg_size * flexbg);
last_grp = group | (flexbg_size - 1);
if (last_grp > fs->group_desc_count-1)
last_grp = fs->group_desc_count-1;
last_blk = ext2fs_group_last_block2(fs, last_grp);
/* Find the first available block */
if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, size,
bmap, &first_free) == 0)
return first_free;
if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, elem_size,
bmap, &first_free) == 0)
return first_free;
if (ext2fs_get_free_blocks2(fs, 0, last_blk, elem_size, bmap,
&first_free) == 0)
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;
blk64_t group_blk, start_blk, last_blk, new_blk;
dgrp_t last_grp = 0;
int rem_grps = 0, flexbg_size = 0, table_offset = 0;
group_blk = ext2fs_group_first_block2(fs, group);
last_blk = ext2fs_group_last_block2(fs, group);
if (!bmap)
bmap = fs->block_map;
if (ext2fs_has_feature_flex_bg(fs->super) &&
fs->super->s_log_groups_per_flex) {
flexbg_size = 1 << fs->super->s_log_groups_per_flex;
last_grp = group | (flexbg_size - 1);
if (last_grp > fs->group_desc_count-1)
last_grp = fs->group_desc_count-1;
rem_grps = last_grp - group + 1;
}
/*
* Allocate the block and inode bitmaps, if necessary
*/
if (fs->stride && !flexbg_size) {
retval = ext2fs_get_free_blocks2(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) {
blk64_t prev_block = 0;
table_offset = flexbg_size;
if (group % flexbg_size)
prev_block = ext2fs_block_bitmap_loc(fs, group - 1) + 1;
else if (last_grp == fs->group_desc_count-1) {
/*
* If we are allocating for the last flex_bg
* keep the metadata tables contiguous
*/
table_offset = last_grp & (flexbg_size - 1);
if (table_offset == 0)
table_offset = flexbg_size;
else
table_offset++;
}
/* FIXME: Take backup group descriptor blocks into account
* if the flexbg allocations will grow to overlap them... */
start_blk = flexbg_offset(fs, group, prev_block, bmap,
rem_grps, 1);
last_blk = ext2fs_group_last_block2(fs, last_grp);
}
if (!ext2fs_block_bitmap_loc(fs, group)) {
retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
1, bmap, &new_blk);
if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
retval = ext2fs_get_free_blocks2(fs, group_blk,
last_blk, 1, bmap, &new_blk);
if (retval)
return retval;
ext2fs_mark_block_bitmap2(bmap, new_blk);
ext2fs_block_bitmap_loc_set(fs, group, new_blk);
if (flexbg_size) {
dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
ext2fs_free_blocks_count_add(fs->super, -1);
ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
ext2fs_group_desc_csum_set(fs, gr);
}
}
if (flexbg_size) {
blk64_t prev_block = 0;
if (group % flexbg_size)
prev_block = ext2fs_inode_bitmap_loc(fs, group - 1) + 1;
else
prev_block = ext2fs_block_bitmap_loc(fs, group) +
table_offset;
/* FIXME: Take backup group descriptor blocks into account
* if the flexbg allocations will grow to overlap them... */
start_blk = flexbg_offset(fs, group, prev_block, bmap,
rem_grps, 1);
last_blk = ext2fs_group_last_block2(fs, last_grp);
}
if (!ext2fs_inode_bitmap_loc(fs, group)) {
retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
1, bmap, &new_blk);
if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
retval = ext2fs_get_free_blocks2(fs, group_blk,
last_blk, 1, bmap, &new_blk);
if (retval)
return retval;
ext2fs_mark_block_bitmap2(bmap, new_blk);
ext2fs_inode_bitmap_loc_set(fs, group, new_blk);
if (flexbg_size) {
dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
ext2fs_free_blocks_count_add(fs->super, -1);
ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
ext2fs_group_desc_csum_set(fs, gr);
}
}
/*
* Allocate the inode table
*/
if (flexbg_size) {
blk64_t prev_block = 0;
if (group % flexbg_size)
prev_block = ext2fs_inode_table_loc(fs, group - 1) +
fs->inode_blocks_per_group;
else
prev_block = ext2fs_inode_bitmap_loc(fs, group) +
table_offset;
/* FIXME: Take backup group descriptor blocks into account
* if the flexbg allocations will grow to overlap them... */
group_blk = flexbg_offset(fs, group, prev_block, bmap,
rem_grps, fs->inode_blocks_per_group);
last_blk = ext2fs_group_last_block2(fs, last_grp);
}
if (!ext2fs_inode_table_loc(fs, group)) {
retval = ext2fs_get_free_blocks2(fs, group_blk, last_blk,
fs->inode_blocks_per_group,
bmap, &new_blk);
if (retval)
return retval;
ext2fs_mark_block_bitmap_range2(bmap,
new_blk, fs->inode_blocks_per_group);
if (flexbg_size) {
blk64_t num, blk;
num = fs->inode_blocks_per_group;
blk = new_blk;
while (num) {
int gr = ext2fs_group_of_blk2(fs, blk);
last_blk = ext2fs_group_last_block2(fs, gr);
blk64_t n = num;
if (blk + num > last_blk)
n = last_blk - blk + 1;
ext2fs_bg_free_blocks_count_set(fs, gr,
ext2fs_bg_free_blocks_count(fs, gr) -
n/EXT2FS_CLUSTER_RATIO(fs));
ext2fs_bg_flags_clear(fs, gr,
EXT2_BG_BLOCK_UNINIT);
ext2fs_group_desc_csum_set(fs, gr);
ext2fs_free_blocks_count_add(fs->super, -n);
blk += n;
num -= n;
}
}
ext2fs_inode_table_loc_set(fs, group, 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;
struct ext2fs_numeric_progress_struct progress;
if (fs->progress_ops && fs->progress_ops->init)
(fs->progress_ops->init)(fs, &progress, NULL,
fs->group_desc_count);
for (i = 0; i < fs->group_desc_count; i++) {
if (fs->progress_ops && fs->progress_ops->update)
(fs->progress_ops->update)(fs, &progress, i);
retval = ext2fs_allocate_group_table(fs, i, fs->block_map);
if (retval)
return retval;
}
if (fs->progress_ops && fs->progress_ops->close)
(fs->progress_ops->close)(fs, &progress, NULL);
return 0;
}