alloc.c revision 4efbac6fed75c29d3d5f1b676b932754653a2ac5
11320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci/* 21320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * alloc.c --- allocate new inodes, blocks for ext2fs 31320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * 41320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o. 51320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * 61320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * %Begin-Header% 71320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * This file may be redistributed under the terms of the GNU Public 81320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * License. 91320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * %End-Header% 101320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * 111320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci */ 121320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 131320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <stdio.h> 141320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#if HAVE_UNISTD_H 151320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <unistd.h> 161320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#endif 171320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <time.h> 181320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <string.h> 191320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#if HAVE_SYS_STAT_H 201320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <sys/stat.h> 211320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#endif 221320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#if HAVE_SYS_TYPES_H 231320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include <sys/types.h> 241320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#endif 251320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 261320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include "ext2_fs.h" 271320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci#include "ext2fs.h" 281320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 291320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci/* 301320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Check for uninit block bitmaps and deal with them appropriately 311320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci */ 321320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tuccistatic void check_block_uninit(ext2_filsys fs, ext2fs_block_bitmap map, 331320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci dgrp_t group) 341320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci{ 351320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci blk_t i; 361320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci blk64_t blk, super_blk, old_desc_blk, new_desc_blk; 371320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci int old_desc_blocks; 381320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 391320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 401320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) || 411320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci !(ext2fs_bg_flag_test(fs, group, EXT2_BG_BLOCK_UNINIT))) 421320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return; 431320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 441320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci blk = (group * fs->super->s_blocks_per_group) + 451320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci fs->super->s_first_data_block; 461320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 471320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_super_and_bgd_loc2(fs, group, &super_blk, 481320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci &old_desc_blk, &new_desc_blk, 0); 491320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 501320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (fs->super->s_feature_incompat & 511320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci EXT2_FEATURE_INCOMPAT_META_BG) 521320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci old_desc_blocks = fs->super->s_first_meta_bg; 531320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci else 541320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci old_desc_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks; 551320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 561320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci for (i=0; i < fs->super->s_blocks_per_group; i++, blk++) { 571320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if ((blk == super_blk) || 581320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (old_desc_blk && old_desc_blocks && 591320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk >= old_desc_blk) && 601320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk < old_desc_blk + old_desc_blocks)) || 611320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (new_desc_blk && (blk == new_desc_blk)) || 621320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk == fs->group_desc[group].bg_block_bitmap) || 631320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk == fs->group_desc[group].bg_inode_bitmap) || 641320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk >= fs->group_desc[group].bg_inode_table && 651320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci (blk < fs->group_desc[group].bg_inode_table 661320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci + fs->inode_blocks_per_group))) 671320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_fast_mark_block_bitmap2(map, blk); 681320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci else 691320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_fast_unmark_block_bitmap2(map, blk); 701320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci } 711320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_bg_flag_clear(fs, group, EXT2_BG_BLOCK_UNINIT); 721320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_group_desc_csum_set(fs, group); 731320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci} 741320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 751320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci/* 761320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Check for uninit inode bitmaps and deal with them appropriately 771320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci */ 781320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tuccistatic void check_inode_uninit(ext2_filsys fs, ext2fs_inode_bitmap map, 791320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci dgrp_t group) 801320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci{ 811320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2_ino_t i, ino; 821320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 831320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 841320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) || 851320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci !(ext2fs_bg_flag_test(fs, group, EXT2_BG_INODE_UNINIT))) 861320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return; 871320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 881320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ino = (group * fs->super->s_inodes_per_group) + 1; 891320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci for (i=0; i < fs->super->s_inodes_per_group; i++, ino++) 901320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_fast_unmark_inode_bitmap2(map, ino); 911320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 921320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_bg_flag_clear(fs, group, EXT2_BG_INODE_UNINIT); 931320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci check_block_uninit(fs, fs->block_map, group); 941320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci} 951320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 961320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci/* 971320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Right now, just search forward from the parent directory's block 981320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * group to find the next free inode. 991320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * 1001320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Should have a special policy for directories. 1011320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci */ 1021320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tuccierrcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir, 1031320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci int mode EXT2FS_ATTR((unused)), 1041320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2fs_inode_bitmap map, ext2_ino_t *ret) 1051320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci{ 1061320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2_ino_t dir_group = 0; 1071320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2_ino_t i; 1081320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci ext2_ino_t start_inode; 1091320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1101320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 1111320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1121320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (!map) 1131320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci map = fs->inode_map; 1141320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (!map) 1151320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return EXT2_ET_NO_INODE_BITMAP; 1161320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1171320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (dir > 0) 1181320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci dir_group = (dir - 1) / EXT2_INODES_PER_GROUP(fs->super); 1191320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1201320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci start_inode = (dir_group * EXT2_INODES_PER_GROUP(fs->super)) + 1; 1211320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (start_inode < EXT2_FIRST_INODE(fs->super)) 1221320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci start_inode = EXT2_FIRST_INODE(fs->super); 1231320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (start_inode > fs->super->s_inodes_count) 1241320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return EXT2_ET_INODE_ALLOC_FAIL; 1251320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci i = start_inode; 1261320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1271320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci do { 1281320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (((i - 1) % EXT2_INODES_PER_GROUP(fs->super)) == 0) 1291320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci check_inode_uninit(fs, map, (i - 1) / 1301320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci EXT2_INODES_PER_GROUP(fs->super)); 1311320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1321320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (!ext2fs_fast_test_inode_bitmap2(map, i)) 1331320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci break; 1341320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci i++; 1351320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (i > fs->super->s_inodes_count) 1361320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci i = EXT2_FIRST_INODE(fs->super); 1371320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci } while (i != start_inode); 1381320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1391320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci if (ext2fs_test_inode_bitmap2(map, i)) 1401320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return EXT2_ET_INODE_ALLOC_FAIL; 1411320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci *ret = i; 1421320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci return 0; 1431320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci} 1441320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci 1451320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci/* 1461320f92c476a1ad9d19dba2a48c72b75566198e9Primiano Tucci * Stupid algorithm --- we now just search forward starting from the 147 * goal. Should put in a smarter one someday.... 148 */ 149errcode_t ext2fs_new_block2(ext2_filsys fs, blk64_t goal, 150 ext2fs_block_bitmap map, blk64_t *ret) 151{ 152 blk64_t i; 153 154 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 155 156 if (!map) 157 map = fs->block_map; 158 if (!map) 159 return EXT2_ET_NO_BLOCK_BITMAP; 160 if (!goal || (goal >= ext2fs_blocks_count(fs->super))) 161 goal = fs->super->s_first_data_block; 162 i = goal; 163 check_block_uninit(fs, map, 164 (i - fs->super->s_first_data_block) / 165 EXT2_BLOCKS_PER_GROUP(fs->super)); 166 do { 167 if (((i - fs->super->s_first_data_block) % 168 EXT2_BLOCKS_PER_GROUP(fs->super)) == 0) 169 check_block_uninit(fs, map, 170 (i - fs->super->s_first_data_block) / 171 EXT2_BLOCKS_PER_GROUP(fs->super)); 172 173 if (!ext2fs_fast_test_block_bitmap2(map, i)) { 174 *ret = i; 175 return 0; 176 } 177 i++; 178 if (i >= ext2fs_blocks_count(fs->super)) 179 i = fs->super->s_first_data_block; 180 } while (i != goal); 181 return EXT2_ET_BLOCK_ALLOC_FAIL; 182} 183 184errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal, 185 ext2fs_block_bitmap map, blk_t *ret) 186{ 187 errcode_t retval; 188 blk64_t val; 189 retval = ext2fs_new_block2(fs, goal, map, &val); 190 if (!retval) 191 *ret = (blk_t) val; 192 return retval; 193} 194 195/* 196 * This function zeros out the allocated block, and updates all of the 197 * appropriate filesystem records. 198 */ 199errcode_t ext2fs_alloc_block2(ext2_filsys fs, blk64_t goal, 200 char *block_buf, blk64_t *ret) 201{ 202 errcode_t retval; 203 blk64_t block; 204 char *buf = 0; 205 206 if (!block_buf) { 207 retval = ext2fs_get_mem(fs->blocksize, &buf); 208 if (retval) 209 return retval; 210 block_buf = buf; 211 } 212 memset(block_buf, 0, fs->blocksize); 213 214 if (fs->get_alloc_block) { 215 retval = (fs->get_alloc_block)(fs, goal, &block); 216 if (retval) 217 goto fail; 218 } else { 219 if (!fs->block_map) { 220 retval = ext2fs_read_block_bitmap(fs); 221 if (retval) 222 goto fail; 223 } 224 225 retval = ext2fs_new_block2(fs, goal, 0, &block); 226 if (retval) 227 goto fail; 228 } 229 230 retval = io_channel_write_blk64(fs->io, block, 1, block_buf); 231 if (retval) 232 goto fail; 233 234 ext2fs_block_alloc_stats2(fs, block, +1); 235 *ret = block; 236 237fail: 238 if (buf) 239 ext2fs_free_mem(&buf); 240 return retval; 241} 242 243errcode_t ext2fs_alloc_block(ext2_filsys fs, blk_t goal, 244 char *block_buf, blk_t *ret) 245{ 246 errcode_t retval; 247 blk64_t val; 248 retval = ext2fs_alloc_block2(fs, goal, block_buf, &val); 249 if (!retval) 250 *ret = (blk_t) val; 251 return retval; 252} 253 254errcode_t ext2fs_get_free_blocks2(ext2_filsys fs, blk64_t start, blk64_t finish, 255 int num, ext2fs_block_bitmap map, blk64_t *ret) 256{ 257 blk64_t b = start; 258 259 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 260 261 if (!map) 262 map = fs->block_map; 263 if (!map) 264 return EXT2_ET_NO_BLOCK_BITMAP; 265 if (!b) 266 b = fs->super->s_first_data_block; 267 if (!finish) 268 finish = start; 269 if (!num) 270 num = 1; 271 do { 272 if (b+num-1 > ext2fs_blocks_count(fs->super)) 273 b = fs->super->s_first_data_block; 274 if (ext2fs_fast_test_block_bitmap_range2(map, b, num)) { 275 *ret = b; 276 return 0; 277 } 278 b++; 279 } while (b != finish); 280 return EXT2_ET_BLOCK_ALLOC_FAIL; 281} 282 283errcode_t ext2fs_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish, 284 int num, ext2fs_block_bitmap map, blk_t *ret) 285{ 286 errcode_t retval; 287 blk64_t val; 288 retval = ext2fs_get_free_blocks2(fs, start, finish, num, map, &val); 289 if(!retval) 290 *ret = (blk_t) val; 291 return retval; 292} 293 294void ext2fs_set_alloc_block_callback(ext2_filsys fs, 295 errcode_t (*func)(ext2_filsys fs, 296 blk64_t goal, 297 blk64_t *ret), 298 errcode_t (**old)(ext2_filsys fs, 299 blk64_t goal, 300 blk64_t *ret)) 301{ 302 if (!fs || fs->magic != EXT2_ET_MAGIC_EXT2FS_FILSYS) 303 return; 304 305 if (old) 306 *old = fs->get_alloc_block; 307 308 fs->get_alloc_block = func; 309} 310