alloc_tables.c revision b49f78fe6e19fe63b6f989d5e1afb04f59069197
1/* 2 * alloc_tables.c --- Allocate tables for a newly initialized 3 * filesystem. Used by mke2fs when initializing a filesystem 4 * 5 * Copyright (C) 1996 Theodore Ts'o. 6 * 7 * %Begin-Header% 8 * This file may be redistributed under the terms of the GNU Public 9 * License. 10 * %End-Header% 11 */ 12 13#include <stdio.h> 14#include <string.h> 15#if HAVE_UNISTD_H 16#include <unistd.h> 17#endif 18#include <fcntl.h> 19#include <time.h> 20#if HAVE_SYS_STAT_H 21#include <sys/stat.h> 22#endif 23#if HAVE_SYS_TYPES_H 24#include <sys/types.h> 25#endif 26 27#include "ext2_fs.h" 28#include "ext2fs.h" 29#include "ext2fsP.h" 30 31/* 32 * This routine searches for free blocks that can allocate a full 33 * group of bitmaps or inode tables for a flexbg group. Returns the 34 * block number with a correct offset were the bitmaps and inode 35 * tables can be allocated continously and in order. 36 */ 37static blk_t flexbg_offset(ext2_filsys fs, dgrp_t group, blk64_t start_blk, 38 ext2fs_block_bitmap bmap, int offset, int size, 39 int elem_size) 40{ 41 int flexbg, flexbg_size; 42 blk_t last_blk, first_free = 0; 43 dgrp_t last_grp; 44 45 flexbg_size = 1 << fs->super->s_log_groups_per_flex; 46 flexbg = group / flexbg_size; 47 48 if (size > (int) (fs->super->s_blocks_per_group / 8)) 49 size = (int) fs->super->s_blocks_per_group / 8; 50 51 if (offset) 52 offset -= 1; 53 54 /* 55 * Don't do a long search if the previous block 56 * search is still valid. 57 */ 58 if (start_blk && group % flexbg_size) { 59 if (ext2fs_test_block_bitmap_range2(bmap, start_blk + elem_size, 60 size)) 61 return start_blk + elem_size; 62 } 63 64 start_blk = ext2fs_group_first_block2(fs, flexbg_size * flexbg); 65 last_grp = group | (flexbg_size - 1); 66 if (last_grp > fs->group_desc_count) 67 last_grp = fs->group_desc_count; 68 last_blk = ext2fs_group_last_block2(fs, last_grp); 69 70 /* Find the first available block */ 71 if (ext2fs_get_free_blocks(fs, start_blk, last_blk, 1, bmap, 72 &first_free)) 73 return first_free; 74 75 if (ext2fs_get_free_blocks(fs, first_free + offset, last_blk, size, 76 bmap, &first_free)) 77 return first_free; 78 79 return first_free; 80} 81 82errcode_t ext2fs_allocate_group_table(ext2_filsys fs, dgrp_t group, 83 ext2fs_block_bitmap bmap) 84{ 85 errcode_t retval; 86 blk_t group_blk, start_blk, last_blk, new_blk, blk; 87 dgrp_t last_grp = 0; 88 int j, rem_grps = 0, flexbg_size = 0; 89 90 group_blk = ext2fs_group_first_block2(fs, group); 91 last_blk = ext2fs_group_last_block2(fs, group); 92 93 if (!bmap) 94 bmap = fs->block_map; 95 96 if (EXT2_HAS_INCOMPAT_FEATURE(fs->super, 97 EXT4_FEATURE_INCOMPAT_FLEX_BG) && 98 fs->super->s_log_groups_per_flex) { 99 flexbg_size = 1 << fs->super->s_log_groups_per_flex; 100 last_grp = group | (flexbg_size - 1); 101 rem_grps = last_grp - group; 102 if (last_grp > fs->group_desc_count) 103 last_grp = fs->group_desc_count; 104 } 105 106 /* 107 * Allocate the block and inode bitmaps, if necessary 108 */ 109 if (fs->stride) { 110 retval = ext2fs_get_free_blocks(fs, group_blk, last_blk, 111 1, bmap, &start_blk); 112 if (retval) 113 return retval; 114 start_blk += fs->inode_blocks_per_group; 115 start_blk += ((fs->stride * group) % 116 (last_blk - start_blk + 1)); 117 if (start_blk >= last_blk) 118 start_blk = group_blk; 119 } else 120 start_blk = group_blk; 121 122 if (flexbg_size) { 123 blk64_t prev_block = 0; 124 125 if (group && ext2fs_block_bitmap_loc(fs, group - 1)) 126 prev_block = ext2fs_block_bitmap_loc(fs, group - 1); 127 start_blk = flexbg_offset(fs, group, prev_block, bmap, 128 0, rem_grps, 1); 129 last_blk = ext2fs_group_last_block2(fs, last_grp); 130 } 131 132 if (!ext2fs_block_bitmap_loc(fs, group)) { 133 retval = ext2fs_get_free_blocks(fs, start_blk, last_blk, 134 1, bmap, &new_blk); 135 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL) 136 retval = ext2fs_get_free_blocks(fs, group_blk, 137 last_blk, 1, bmap, &new_blk); 138 if (retval) 139 return retval; 140 ext2fs_mark_block_bitmap2(bmap, new_blk); 141 ext2fs_block_bitmap_loc_set(fs, group, new_blk); 142 if (flexbg_size) { 143 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk); 144 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1); 145 ext2fs_free_blocks_count_add(fs->super, -1); 146 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT); 147 ext2fs_group_desc_csum_set(fs, gr); 148 } 149 } 150 151 if (flexbg_size) { 152 blk64_t prev_block = 0; 153 if (group && ext2fs_inode_bitmap_loc(fs, group - 1)) 154 prev_block = ext2fs_inode_bitmap_loc(fs, group - 1); 155 start_blk = flexbg_offset(fs, group, prev_block, bmap, 156 flexbg_size, rem_grps, 1); 157 last_blk = ext2fs_group_last_block2(fs, last_grp); 158 } 159 160 if (!ext2fs_inode_bitmap_loc(fs, group)) { 161 retval = ext2fs_get_free_blocks(fs, start_blk, last_blk, 162 1, bmap, &new_blk); 163 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL) 164 retval = ext2fs_get_free_blocks(fs, group_blk, 165 last_blk, 1, bmap, &new_blk); 166 if (retval) 167 return retval; 168 ext2fs_mark_block_bitmap2(bmap, new_blk); 169 ext2fs_inode_bitmap_loc_set(fs, group, new_blk); 170 if (flexbg_size) { 171 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk); 172 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1); 173 ext2fs_free_blocks_count_add(fs->super, -1); 174 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT); 175 ext2fs_group_desc_csum_set(fs, gr); 176 } 177 } 178 179 /* 180 * Allocate the inode table 181 */ 182 if (flexbg_size) { 183 blk64_t prev_block = 0; 184 if (group && ext2fs_inode_table_loc(fs, group - 1)) 185 prev_block = ext2fs_inode_table_loc(fs, group - 1); 186 group_blk = flexbg_offset(fs, group, prev_block, bmap, 187 flexbg_size * 2, 188 fs->inode_blocks_per_group * 189 rem_grps, 190 fs->inode_blocks_per_group); 191 last_blk = ext2fs_group_last_block2(fs, last_grp); 192 } 193 194 if (!ext2fs_inode_table_loc(fs, group)) { 195 retval = ext2fs_get_free_blocks(fs, group_blk, last_blk, 196 fs->inode_blocks_per_group, 197 bmap, &new_blk); 198 if (retval) 199 return retval; 200 for (j=0, blk = new_blk; 201 j < fs->inode_blocks_per_group; 202 j++, blk++) { 203 ext2fs_mark_block_bitmap2(bmap, blk); 204 if (flexbg_size) { 205 dgrp_t gr = ext2fs_group_of_blk2(fs, blk); 206 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1); 207 ext2fs_free_blocks_count_add(fs->super, -1); 208 ext2fs_bg_flags_clear(fs, gr, 209 EXT2_BG_BLOCK_UNINIT); 210 ext2fs_group_desc_csum_set(fs, gr); 211 } 212 } 213 ext2fs_inode_table_loc_set(fs, group, new_blk); 214 } 215 ext2fs_group_desc_csum_set(fs, group); 216 return 0; 217} 218 219errcode_t ext2fs_allocate_tables(ext2_filsys fs) 220{ 221 errcode_t retval; 222 dgrp_t i; 223 struct ext2fs_numeric_progress_struct progress; 224 225 ext2fs_numeric_progress_init(fs, &progress, NULL, 226 fs->group_desc_count); 227 228 for (i = 0; i < fs->group_desc_count; i++) { 229 ext2fs_numeric_progress_update(fs, &progress, i); 230 retval = ext2fs_allocate_group_table(fs, i, fs->block_map); 231 if (retval) 232 return retval; 233 } 234 ext2fs_numeric_progress_close(fs, &progress, NULL); 235 return 0; 236} 237 238