/*
* 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 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 / 8))
size = (int) fs->super->s_blocks_per_group / 8;
/*
* Don't do a long search if the previous block
* search is still valid.
*/
if (start_blk && ext2fs_test_block_bitmap_range2(bmap, start_blk,
elem_size))
return start_blk;
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_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish,
int num, ext2fs_block_bitmap map, blk_t *ret)
{
errcode_t retval;
blk64_t val;
retval = ext2fs_get_free_blocks2(fs, start, finish, num, map, &val);
if(!retval)
*ret = (blk_t) val;
return retval;
}
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;
group_blk = ext2fs_group_first_block2(fs, group);
last_blk = ext2fs_group_last_block2(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);
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) {
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;
if (group % flexbg_size)
prev_block = ext2fs_block_bitmap_loc(fs, group - 1) + 1;
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) +
flexbg_size;
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) +
flexbg_size;
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;
if (flexbg_size)
ext2fs_block_alloc_stats_range(fs, new_blk,
fs->inode_blocks_per_group, +1);
else
ext2fs_mark_block_bitmap_range2(fs->block_map,
new_blk, fs->inode_blocks_per_group);
ext2fs_inode_table_loc_set(fs, group, new_blk);
}
ext2fs_group_desc_csum_set(fs, group);
return 0;
}
