LXR busybox/e2fsprogs/old_e2fsprogs/ext2fs/alloc

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * alloc_sb.c --- Allocate the superblock and block group descriptors for a
   4 * newly initialized filesystem.  Used by mke2fs when initializing a filesystem
   5 *
   6 * Copyright (C) 1994, 1995, 1996, 2003 Theodore Ts'o.
   7 *
   8 * %Begin-Header%
   9 * This file may be redistributed under the terms of the GNU Public
  10 * License.
  11 * %End-Header%
  12 */
  13
  14#include <stdio.h>
  15#include <string.h>
  16#if HAVE_UNISTD_H
  17#include <unistd.h>
  18#endif
  19#include <fcntl.h>
  20#include <time.h>
  21#if HAVE_SYS_STAT_H
  22#include <sys/stat.h>
  23#endif
  24#if HAVE_SYS_TYPES_H
  25#include <sys/types.h>
  26#endif
  27
  28#include "ext2_fs.h"
  29#include "ext2fs.h"
  30
  31int ext2fs_reserve_super_and_bgd(ext2_filsys fs,
  32                                 dgrp_t group,
  33                                 ext2fs_block_bitmap bmap)
  34{
  35        blk_t   super_blk, old_desc_blk, new_desc_blk;
  36        int     j, old_desc_blocks, num_blocks;
  37
  38        num_blocks = ext2fs_super_and_bgd_loc(fs, group, &super_blk,
  39                                              &old_desc_blk, &new_desc_blk, 0);
  40
  41        if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
  42                old_desc_blocks = fs->super->s_first_meta_bg;
  43        else
  44                old_desc_blocks =
  45                        fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
  46
  47        if (super_blk || (group == 0))
  48                ext2fs_mark_block_bitmap(bmap, super_blk);
  49
  50        if (old_desc_blk) {
  51                for (j=0; j < old_desc_blocks; j++)
  52                        ext2fs_mark_block_bitmap(bmap, old_desc_blk + j);
  53        }
  54        if (new_desc_blk)
  55                ext2fs_mark_block_bitmap(bmap, new_desc_blk);
  56
  57        return num_blocks;
  58}
  59