alloc.c revision 9f8046fc6dfc13eee2f5c363214e60b533872cac
15f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)/* 25f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * alloc.c --- allocate new inodes, blocks for ext2fs 35f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * 45f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o. 55f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * 65f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * %Begin-Header% 75f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * This file may be redistributed under the terms of the GNU Public 85f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * License. 95f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * %End-Header% 105f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * 115f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) */ 125f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 135f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <stdio.h> 145f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#if HAVE_UNISTD_H 155f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <unistd.h> 165f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#endif 175f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <time.h> 185f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <string.h> 195f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#if HAVE_SYS_STAT_H 205f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <sys/stat.h> 215f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#endif 225f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#if HAVE_SYS_TYPES_H 235f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include <sys/types.h> 245f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#endif 255f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 265f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "ext2_fs.h" 275f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "ext2fs.h" 285f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 295f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)/* 305f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * Right now, just search forward from the parent directory's block 315f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * group to find the next free inode. 325f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * 335f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * Should have a special policy for directories. 345f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) */ 355f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)errcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir, int mode, 365f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) ext2fs_inode_bitmap map, ext2_ino_t *ret) 375f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles){ 385f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) ext2_ino_t dir_group = 0; 395f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) ext2_ino_t i; 405f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) ext2_ino_t start_inode; 415f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 425f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 435f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 445f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!map) 455f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) map = fs->inode_map; 465f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!map) 475f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) return EXT2_ET_NO_INODE_BITMAP; 485f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 495f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (dir > 0) 505f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) dir_group = (dir - 1) / EXT2_INODES_PER_GROUP(fs->super); 515f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 525f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) start_inode = (dir_group * EXT2_INODES_PER_GROUP(fs->super)) + 1; 535f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (start_inode < EXT2_FIRST_INODE(fs->super)) 545f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) start_inode = EXT2_FIRST_INODE(fs->super); 555f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) i = start_inode; 565f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 575f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) do { 585f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!ext2fs_test_inode_bitmap(map, i)) 595f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) break; 605f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) i++; 615f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (i > fs->super->s_inodes_count) 625f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) i = EXT2_FIRST_INODE(fs->super); 635f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) } while (i != start_inode); 645f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 655f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (ext2fs_test_inode_bitmap(map, i)) 665f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) return EXT2_ET_INODE_ALLOC_FAIL; 675f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) *ret = i; 685f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) return 0; 695f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)} 705f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 715f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)/* 725f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * Stupid algorithm --- we now just search forward starting from the 735f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) * goal. Should put in a smarter one someday.... 745f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) */ 755f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal, 765f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) ext2fs_block_bitmap map, blk_t *ret) 775f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles){ 785f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) blk_t i; 795f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 805f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 815f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 825f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!map) 835f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) map = fs->block_map; 845f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!map) 855f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) return EXT2_ET_NO_BLOCK_BITMAP; 865f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!goal || (goal >= fs->super->s_blocks_count)) 875f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) goal = fs->super->s_first_data_block; 885f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) i = goal; 895f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) do { 905f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) if (!ext2fs_test_block_bitmap(map, i)) { 915f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) *ret = i; 925f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) return 0; 935f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) } 945f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) i++; 95 if (i >= fs->super->s_blocks_count) 96 i = fs->super->s_first_data_block; 97 } while (i != goal); 98 return EXT2_ET_BLOCK_ALLOC_FAIL; 99} 100 101/* 102 * This function zeros out the allocated block, and updates all of the 103 * appropriate filesystem records. 104 */ 105errcode_t ext2fs_alloc_block(ext2_filsys fs, blk_t goal, 106 char *block_buf, blk_t *ret) 107{ 108 errcode_t retval; 109 blk_t block; 110 int group; 111 char *buf = 0; 112 113 if (!block_buf) { 114 retval = ext2fs_get_mem(fs->blocksize, (void **) &buf); 115 if (retval) 116 return retval; 117 block_buf = buf; 118 } 119 memset(block_buf, 0, fs->blocksize); 120 121 if (!fs->block_map) { 122 retval = ext2fs_read_block_bitmap(fs); 123 if (retval) 124 goto fail; 125 } 126 127 retval = ext2fs_new_block(fs, goal, 0, &block); 128 if (retval) 129 goto fail; 130 131 retval = io_channel_write_blk(fs->io, block, 1, block_buf); 132 if (retval) 133 goto fail; 134 135 fs->super->s_free_blocks_count--; 136 group = ext2fs_group_of_blk(fs, block); 137 fs->group_desc[group].bg_free_blocks_count--; 138 ext2fs_mark_block_bitmap(fs->block_map, block); 139 ext2fs_mark_super_dirty(fs); 140 ext2fs_mark_bb_dirty(fs); 141 *ret = block; 142 return 0; 143 144fail: 145 if (buf) 146 ext2fs_free_mem((void **) &buf); 147 return retval; 148} 149 150errcode_t ext2fs_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish, 151 int num, ext2fs_block_bitmap map, blk_t *ret) 152{ 153 blk_t b = start; 154 155 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 156 157 if (!map) 158 map = fs->block_map; 159 if (!map) 160 return EXT2_ET_NO_BLOCK_BITMAP; 161 if (!b) 162 b = fs->super->s_first_data_block; 163 if (!finish) 164 finish = start; 165 if (!num) 166 num = 1; 167 do { 168 if (b+num-1 > fs->super->s_blocks_count) 169 b = fs->super->s_first_data_block; 170 if (ext2fs_fast_test_block_bitmap_range(map, b, num)) { 171 *ret = b; 172 return 0; 173 } 174 b++; 175 } while (b != finish); 176 return EXT2_ET_BLOCK_ALLOC_FAIL; 177} 178 179