LXR busybox/e2fsprogs/old_e2fsprogs/ext2fs/alloc

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * alloc_tables.c --- Allocate tables for a newly initialized
   4 * filesystem.  Used by mke2fs when initializing a filesystem
   5 *
   6 * Copyright (C) 1996 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
  31errcode_t ext2fs_allocate_group_table(ext2_filsys fs, dgrp_t group,
  32                                      ext2fs_block_bitmap bmap)
  33{
  34        errcode_t       retval;
  35        blk_t           group_blk, start_blk, last_blk, new_blk, blk;
  36        int             j;
  37
  38        group_blk = fs->super->s_first_data_block +
  39                (group * fs->super->s_blocks_per_group);
  40
  41        last_blk = group_blk + fs->super->s_blocks_per_group;
  42        if (last_blk >= fs->super->s_blocks_count)
  43                last_blk = fs->super->s_blocks_count - 1;
  44
  45        if (!bmap)
  46                bmap = fs->block_map;
  47
  48        /*
  49         * Allocate the block and inode bitmaps, if necessary
  50         */
  51        if (fs->stride) {
  52                start_blk = group_blk + fs->inode_blocks_per_group;
  53                start_blk += ((fs->stride * group) %
  54                              (last_blk - start_blk));
  55                if (start_blk > last_blk)
  56                        start_blk = group_blk;
  57        } else
  58                start_blk = group_blk;
  59
  60        if (!fs->group_desc[group].bg_block_bitmap) {
  61                retval = ext2fs_get_free_blocks(fs, start_blk, last_blk,
  62                                                1, bmap, &new_blk);
  63                if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
  64                        retval = ext2fs_get_free_blocks(fs, group_blk,
  65                                        last_blk, 1, bmap, &new_blk);
  66                if (retval)
  67                        return retval;
  68                ext2fs_mark_block_bitmap(bmap, new_blk);
  69                fs->group_desc[group].bg_block_bitmap = new_blk;
  70        }
  71
  72        if (!fs->group_desc[group].bg_inode_bitmap) {
  73                retval = ext2fs_get_free_blocks(fs, start_blk, last_blk,
  74                                                1, bmap, &new_blk);
  75                if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
  76                        retval = ext2fs_get_free_blocks(fs, group_blk,
  77                                        last_blk, 1, bmap, &new_blk);
  78                if (retval)
  79                        return retval;
  80                ext2fs_mark_block_bitmap(bmap, new_blk);
  81                fs->group_desc[group].bg_inode_bitmap = new_blk;
  82        }
  83
  84        /*
  85         * Allocate the inode table
  86         */
  87        if (!fs->group_desc[group].bg_inode_table) {
  88                retval = ext2fs_get_free_blocks(fs, group_blk, last_blk,
  89                                                fs->inode_blocks_per_group,
  90                                                bmap, &new_blk);
  91                if (retval)
  92                        return retval;
  93                for (j=0, blk = new_blk;
  94                     j < fs->inode_blocks_per_group;
  95                     j++, blk++)
  96                        ext2fs_mark_block_bitmap(bmap, blk);
  97                fs->group_desc[group].bg_inode_table = new_blk;
  98        }
  99
 100
 101        return 0;
 102}
 103
 104
 105
 106errcode_t ext2fs_allocate_tables(ext2_filsys fs)
 107{
 108        errcode_t       retval;
 109        dgrp_t          i;
 110
 111        for (i = 0; i < fs->group_desc_count; i++) {
 112                retval = ext2fs_allocate_group_table(fs, i, fs->block_map);
 113                if (retval)
 114                        return retval;
 115        }
 116        return 0;
 117}
 118
 119