1 /* 2 * inode.c --- utility routines to read and write inodes 3 * 4 * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o. 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Public 8 * License. 9 * %End-Header% 10 */ 11 12 #include <stdio.h> 13 #include <string.h> 14 #if HAVE_UNISTD_H 15 #include <unistd.h> 16 #endif 17 #if HAVE_ERRNO_H 18 #include <errno.h> 19 #endif 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 "ext2fsP.h" 30 #include "e2image.h" 31 32 struct ext2_struct_inode_scan { 33 errcode_t magic; 34 ext2_filsys fs; 35 ext2_ino_t current_inode; 36 blk_t current_block; 37 dgrp_t current_group; 38 ext2_ino_t inodes_left; 39 blk_t blocks_left; 40 dgrp_t groups_left; 41 blk_t inode_buffer_blocks; 42 char * inode_buffer; 43 int inode_size; 44 char * ptr; 45 int bytes_left; 46 char *temp_buffer; 47 errcode_t (*done_group)(ext2_filsys fs, 48 ext2_inode_scan scan, 49 dgrp_t group, 50 void * priv_data); 51 void * done_group_data; 52 int bad_block_ptr; 53 int scan_flags; 54 int reserved[6]; 55 }; 56 57 /* 58 * This routine flushes the icache, if it exists. 59 */ 60 errcode_t ext2fs_flush_icache(ext2_filsys fs) 61 { 62 int i; 63 64 if (!fs->icache) 65 return 0; 66 67 for (i=0; i < fs->icache->cache_size; i++) 68 fs->icache->cache[i].ino = 0; 69 70 fs->icache->buffer_blk = 0; 71 return 0; 72 } 73 74 static errcode_t create_icache(ext2_filsys fs) 75 { 76 errcode_t retval; 77 78 if (fs->icache) 79 return 0; 80 retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache); 81 if (retval) 82 return retval; 83 84 memset(fs->icache, 0, sizeof(struct ext2_inode_cache)); 85 retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer); 86 if (retval) { 87 ext2fs_free_mem(&fs->icache); 88 return retval; 89 } 90 fs->icache->buffer_blk = 0; 91 fs->icache->cache_last = -1; 92 fs->icache->cache_size = 4; 93 fs->icache->refcount = 1; 94 retval = ext2fs_get_array(fs->icache->cache_size, 95 sizeof(struct ext2_inode_cache_ent), 96 &fs->icache->cache); 97 if (retval) { 98 ext2fs_free_mem(&fs->icache->buffer); 99 ext2fs_free_mem(&fs->icache); 100 return retval; 101 } 102 ext2fs_flush_icache(fs); 103 return 0; 104 } 105 106 errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks, 107 ext2_inode_scan *ret_scan) 108 { 109 ext2_inode_scan scan; 110 errcode_t retval; 111 errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks); 112 113 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 114 115 /* 116 * If fs->badblocks isn't set, then set it --- since the inode 117 * scanning functions require it. 118 */ 119 if (fs->badblocks == 0) { 120 /* 121 * Temporarly save fs->get_blocks and set it to zero, 122 * for compatibility with old e2fsck's. 123 */ 124 save_get_blocks = fs->get_blocks; 125 fs->get_blocks = 0; 126 retval = ext2fs_read_bb_inode(fs, &fs->badblocks); 127 if (retval && fs->badblocks) { 128 ext2fs_badblocks_list_free(fs->badblocks); 129 fs->badblocks = 0; 130 } 131 fs->get_blocks = save_get_blocks; 132 } 133 134 retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan); 135 if (retval) 136 return retval; 137 memset(scan, 0, sizeof(struct ext2_struct_inode_scan)); 138 139 scan->magic = EXT2_ET_MAGIC_INODE_SCAN; 140 scan->fs = fs; 141 scan->inode_size = EXT2_INODE_SIZE(fs->super); 142 scan->bytes_left = 0; 143 scan->current_group = 0; 144 scan->groups_left = fs->group_desc_count - 1; 145 scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8; 146 scan->current_block = scan->fs-> 147 group_desc[scan->current_group].bg_inode_table; 148 scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); 149 scan->blocks_left = scan->fs->inode_blocks_per_group; 150 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 151 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { 152 scan->inodes_left -= 153 fs->group_desc[scan->current_group].bg_itable_unused; 154 scan->blocks_left = 155 (scan->inodes_left + 156 (fs->blocksize / scan->inode_size - 1)) * 157 scan->inode_size / fs->blocksize; 158 } 159 retval = ext2fs_get_array(scan->inode_buffer_blocks, 160 fs->blocksize, 161 &scan->inode_buffer); 162 scan->done_group = 0; 163 scan->done_group_data = 0; 164 scan->bad_block_ptr = 0; 165 if (retval) { 166 ext2fs_free_mem(&scan); 167 return retval; 168 } 169 retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer); 170 if (retval) { 171 ext2fs_free_mem(&scan->inode_buffer); 172 ext2fs_free_mem(&scan); 173 return retval; 174 } 175 if (scan->fs->badblocks && scan->fs->badblocks->num) 176 scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS; 177 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 178 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) 179 scan->scan_flags |= EXT2_SF_DO_LAZY; 180 *ret_scan = scan; 181 return 0; 182 } 183 184 void ext2fs_close_inode_scan(ext2_inode_scan scan) 185 { 186 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 187 return; 188 189 ext2fs_free_mem(&scan->inode_buffer); 190 scan->inode_buffer = NULL; 191 ext2fs_free_mem(&scan->temp_buffer); 192 scan->temp_buffer = NULL; 193 ext2fs_free_mem(&scan); 194 return; 195 } 196 197 void ext2fs_set_inode_callback(ext2_inode_scan scan, 198 errcode_t (*done_group)(ext2_filsys fs, 199 ext2_inode_scan scan, 200 dgrp_t group, 201 void * priv_data), 202 void *done_group_data) 203 { 204 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 205 return; 206 207 scan->done_group = done_group; 208 scan->done_group_data = done_group_data; 209 } 210 211 int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags, 212 int clear_flags) 213 { 214 int old_flags; 215 216 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 217 return 0; 218 219 old_flags = scan->scan_flags; 220 scan->scan_flags &= ~clear_flags; 221 scan->scan_flags |= set_flags; 222 return old_flags; 223 } 224 225 /* 226 * This function is called by ext2fs_get_next_inode when it needs to 227 * get ready to read in a new blockgroup. 228 */ 229 static errcode_t get_next_blockgroup(ext2_inode_scan scan) 230 { 231 ext2_filsys fs = scan->fs; 232 233 scan->current_group++; 234 scan->groups_left--; 235 236 scan->current_block =fs->group_desc[scan->current_group].bg_inode_table; 237 238 scan->current_inode = scan->current_group * 239 EXT2_INODES_PER_GROUP(fs->super); 240 241 scan->bytes_left = 0; 242 scan->inodes_left = EXT2_INODES_PER_GROUP(fs->super); 243 scan->blocks_left = fs->inode_blocks_per_group; 244 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 245 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { 246 scan->inodes_left -= 247 fs->group_desc[scan->current_group].bg_itable_unused; 248 scan->blocks_left = 249 (scan->inodes_left + 250 (fs->blocksize / scan->inode_size - 1)) * 251 scan->inode_size / fs->blocksize; 252 } 253 254 return 0; 255 } 256 257 errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan, 258 int group) 259 { 260 scan->current_group = group - 1; 261 scan->groups_left = scan->fs->group_desc_count - group; 262 return get_next_blockgroup(scan); 263 } 264 265 /* 266 * This function is called by get_next_blocks() to check for bad 267 * blocks in the inode table. 268 * 269 * This function assumes that badblocks_list->list is sorted in 270 * increasing order. 271 */ 272 static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan, 273 blk_t *num_blocks) 274 { 275 blk_t blk = scan->current_block; 276 badblocks_list bb = scan->fs->badblocks; 277 278 /* 279 * If the inode table is missing, then obviously there are no 280 * bad blocks. :-) 281 */ 282 if (blk == 0) 283 return 0; 284 285 /* 286 * If the current block is greater than the bad block listed 287 * in the bad block list, then advance the pointer until this 288 * is no longer the case. If we run out of bad blocks, then 289 * we don't need to do any more checking! 290 */ 291 while (blk > bb->list[scan->bad_block_ptr]) { 292 if (++scan->bad_block_ptr >= bb->num) { 293 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 294 return 0; 295 } 296 } 297 298 /* 299 * If the current block is equal to the bad block listed in 300 * the bad block list, then handle that one block specially. 301 * (We could try to handle runs of bad blocks, but that 302 * only increases CPU efficiency by a small amount, at the 303 * expense of a huge expense of code complexity, and for an 304 * uncommon case at that.) 305 */ 306 if (blk == bb->list[scan->bad_block_ptr]) { 307 scan->scan_flags |= EXT2_SF_BAD_INODE_BLK; 308 *num_blocks = 1; 309 if (++scan->bad_block_ptr >= bb->num) 310 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 311 return 0; 312 } 313 314 /* 315 * If there is a bad block in the range that we're about to 316 * read in, adjust the number of blocks to read so that we we 317 * don't read in the bad block. (Then the next block to read 318 * will be the bad block, which is handled in the above case.) 319 */ 320 if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr]) 321 *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk); 322 323 return 0; 324 } 325 326 /* 327 * This function is called by ext2fs_get_next_inode when it needs to 328 * read in more blocks from the current blockgroup's inode table. 329 */ 330 static errcode_t get_next_blocks(ext2_inode_scan scan) 331 { 332 blk_t num_blocks; 333 errcode_t retval; 334 335 /* 336 * Figure out how many blocks to read; we read at most 337 * inode_buffer_blocks, and perhaps less if there aren't that 338 * many blocks left to read. 339 */ 340 num_blocks = scan->inode_buffer_blocks; 341 if (num_blocks > scan->blocks_left) 342 num_blocks = scan->blocks_left; 343 344 /* 345 * If the past block "read" was a bad block, then mark the 346 * left-over extra bytes as also being bad. 347 */ 348 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) { 349 if (scan->bytes_left) 350 scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES; 351 scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK; 352 } 353 354 /* 355 * Do inode bad block processing, if necessary. 356 */ 357 if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) { 358 retval = check_for_inode_bad_blocks(scan, &num_blocks); 359 if (retval) 360 return retval; 361 } 362 363 if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) || 364 (scan->current_block == 0)) { 365 memset(scan->inode_buffer, 0, 366 (size_t) num_blocks * scan->fs->blocksize); 367 } else { 368 retval = io_channel_read_blk(scan->fs->io, 369 scan->current_block, 370 (int) num_blocks, 371 scan->inode_buffer); 372 if (retval) 373 return EXT2_ET_NEXT_INODE_READ; 374 } 375 scan->ptr = scan->inode_buffer; 376 scan->bytes_left = num_blocks * scan->fs->blocksize; 377 378 scan->blocks_left -= num_blocks; 379 if (scan->current_block) 380 scan->current_block += num_blocks; 381 return 0; 382 } 383 384 #if 0 385 /* 386 * Returns 1 if the entire inode_buffer has a non-zero size and 387 * contains all zeros. (Not just deleted inodes, since that means 388 * that part of the inode table was used at one point; we want all 389 * zeros, which means that the inode table is pristine.) 390 */ 391 static inline int is_empty_scan(ext2_inode_scan scan) 392 { 393 int i; 394 395 if (scan->bytes_left == 0) 396 return 0; 397 398 for (i=0; i < scan->bytes_left; i++) 399 if (scan->ptr[i]) 400 return 0; 401 return 1; 402 } 403 #endif 404 405 errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, 406 struct ext2_inode *inode, int bufsize) 407 { 408 errcode_t retval; 409 int extra_bytes = 0; 410 411 EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN); 412 413 /* 414 * Do we need to start reading a new block group? 415 */ 416 if (scan->inodes_left <= 0) { 417 force_new_group: 418 if (scan->done_group) { 419 retval = (scan->done_group) 420 (scan->fs, scan, scan->current_group, 421 scan->done_group_data); 422 if (retval) 423 return retval; 424 } 425 if (scan->groups_left <= 0) { 426 *ino = 0; 427 return 0; 428 } 429 retval = get_next_blockgroup(scan); 430 if (retval) 431 return retval; 432 } 433 /* 434 * These checks are done outside the above if statement so 435 * they can be done for block group #0. 436 */ 437 if ((scan->scan_flags & EXT2_SF_DO_LAZY) && 438 (scan->fs->group_desc[scan->current_group].bg_flags & 439 EXT2_BG_INODE_UNINIT)) 440 goto force_new_group; 441 if (scan->inodes_left == 0) 442 goto force_new_group; 443 if (scan->current_block == 0) { 444 if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) { 445 goto force_new_group; 446 } else 447 return EXT2_ET_MISSING_INODE_TABLE; 448 } 449 450 451 /* 452 * Have we run out of space in the inode buffer? If so, we 453 * need to read in more blocks. 454 */ 455 if (scan->bytes_left < scan->inode_size) { 456 memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left); 457 extra_bytes = scan->bytes_left; 458 459 retval = get_next_blocks(scan); 460 if (retval) 461 return retval; 462 #if 0 463 /* 464 * XXX test Need check for used inode somehow. 465 * (Note: this is hard.) 466 */ 467 if (is_empty_scan(scan)) 468 goto force_new_group; 469 #endif 470 } 471 472 retval = 0; 473 if (extra_bytes) { 474 memcpy(scan->temp_buffer+extra_bytes, scan->ptr, 475 scan->inode_size - extra_bytes); 476 scan->ptr += scan->inode_size - extra_bytes; 477 scan->bytes_left -= scan->inode_size - extra_bytes; 478 479 #ifdef WORDS_BIGENDIAN 480 memset(inode, 0, bufsize); 481 ext2fs_swap_inode_full(scan->fs, 482 (struct ext2_inode_large *) inode, 483 (struct ext2_inode_large *) scan->temp_buffer, 484 0, bufsize); 485 #else 486 *inode = *((struct ext2_inode *) scan->temp_buffer); 487 #endif 488 if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES) 489 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 490 scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES; 491 } else { 492 #ifdef WORDS_BIGENDIAN 493 memset(inode, 0, bufsize); 494 ext2fs_swap_inode_full(scan->fs, 495 (struct ext2_inode_large *) inode, 496 (struct ext2_inode_large *) scan->ptr, 497 0, bufsize); 498 #else 499 memcpy(inode, scan->ptr, bufsize); 500 #endif 501 scan->ptr += scan->inode_size; 502 scan->bytes_left -= scan->inode_size; 503 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) 504 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 505 } 506 507 scan->inodes_left--; 508 scan->current_inode++; 509 *ino = scan->current_inode; 510 return retval; 511 } 512 513 errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino, 514 struct ext2_inode *inode) 515 { 516 return ext2fs_get_next_inode_full(scan, ino, inode, 517 sizeof(struct ext2_inode)); 518 } 519 520 /* 521 * Functions to read and write a single inode. 522 */ 523 errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, 524 struct ext2_inode * inode, int bufsize) 525 { 526 unsigned long group, block, block_nr, offset; 527 char *ptr; 528 errcode_t retval; 529 int clen, i, inodes_per_block, length; 530 io_channel io; 531 532 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 533 534 /* Check to see if user has an override function */ 535 if (fs->read_inode) { 536 retval = (fs->read_inode)(fs, ino, inode); 537 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 538 return retval; 539 } 540 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 541 return EXT2_ET_BAD_INODE_NUM; 542 /* Create inode cache if not present */ 543 if (!fs->icache) { 544 retval = create_icache(fs); 545 if (retval) 546 return retval; 547 } 548 /* Check to see if it's in the inode cache */ 549 if (bufsize == sizeof(struct ext2_inode)) { 550 /* only old good inode can be retrieved from the cache */ 551 for (i=0; i < fs->icache->cache_size; i++) { 552 if (fs->icache->cache[i].ino == ino) { 553 *inode = fs->icache->cache[i].inode; 554 return 0; 555 } 556 } 557 } 558 if (fs->flags & EXT2_FLAG_IMAGE_FILE) { 559 inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); 560 block_nr = fs->image_header->offset_inode / fs->blocksize; 561 block_nr += (ino - 1) / inodes_per_block; 562 offset = ((ino - 1) % inodes_per_block) * 563 EXT2_INODE_SIZE(fs->super); 564 io = fs->image_io; 565 } else { 566 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 567 if (group > fs->group_desc_count) 568 return EXT2_ET_BAD_INODE_NUM; 569 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 570 EXT2_INODE_SIZE(fs->super); 571 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 572 if (!fs->group_desc[(unsigned)group].bg_inode_table) 573 return EXT2_ET_MISSING_INODE_TABLE; 574 block_nr = fs->group_desc[(unsigned)group].bg_inode_table + 575 block; 576 io = fs->io; 577 } 578 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 579 580 length = EXT2_INODE_SIZE(fs->super); 581 if (bufsize < length) 582 length = bufsize; 583 584 ptr = (char *) inode; 585 while (length) { 586 clen = length; 587 if ((offset + length) > fs->blocksize) 588 clen = fs->blocksize - offset; 589 590 if (block_nr != fs->icache->buffer_blk) { 591 retval = io_channel_read_blk(io, block_nr, 1, 592 fs->icache->buffer); 593 if (retval) 594 return retval; 595 fs->icache->buffer_blk = block_nr; 596 } 597 598 memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset, 599 clen); 600 601 offset = 0; 602 length -= clen; 603 ptr += clen; 604 block_nr++; 605 } 606 607 #ifdef WORDS_BIGENDIAN 608 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode, 609 (struct ext2_inode_large *) inode, 610 0, bufsize); 611 #endif 612 613 /* Update the inode cache */ 614 fs->icache->cache_last = (fs->icache->cache_last + 1) % 615 fs->icache->cache_size; 616 fs->icache->cache[fs->icache->cache_last].ino = ino; 617 fs->icache->cache[fs->icache->cache_last].inode = *inode; 618 619 return 0; 620 } 621 622 errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino, 623 struct ext2_inode * inode) 624 { 625 return ext2fs_read_inode_full(fs, ino, inode, 626 sizeof(struct ext2_inode)); 627 } 628 629 errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, 630 struct ext2_inode * inode, int bufsize) 631 { 632 unsigned long group, block, block_nr, offset; 633 errcode_t retval = 0; 634 struct ext2_inode_large temp_inode, *w_inode; 635 char *ptr; 636 int clen, i, length; 637 638 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 639 640 /* Check to see if user provided an override function */ 641 if (fs->write_inode) { 642 retval = (fs->write_inode)(fs, ino, inode); 643 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 644 return retval; 645 } 646 647 /* Check to see if the inode cache needs to be updated */ 648 if (fs->icache) { 649 for (i=0; i < fs->icache->cache_size; i++) { 650 if (fs->icache->cache[i].ino == ino) { 651 fs->icache->cache[i].inode = *inode; 652 break; 653 } 654 } 655 } else { 656 retval = create_icache(fs); 657 if (retval) 658 return retval; 659 } 660 661 if (!(fs->flags & EXT2_FLAG_RW)) 662 return EXT2_ET_RO_FILSYS; 663 664 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 665 return EXT2_ET_BAD_INODE_NUM; 666 667 length = bufsize; 668 if (length < EXT2_INODE_SIZE(fs->super)) 669 length = EXT2_INODE_SIZE(fs->super); 670 671 if (length > (int) sizeof(struct ext2_inode_large)) { 672 w_inode = malloc(length); 673 if (!w_inode) 674 return ENOMEM; 675 } else 676 w_inode = &temp_inode; 677 memset(w_inode, 0, length); 678 679 #ifdef WORDS_BIGENDIAN 680 ext2fs_swap_inode_full(fs, w_inode, 681 (struct ext2_inode_large *) inode, 682 1, bufsize); 683 #else 684 memcpy(w_inode, inode, bufsize); 685 #endif 686 687 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 688 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 689 EXT2_INODE_SIZE(fs->super); 690 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 691 if (!fs->group_desc[(unsigned) group].bg_inode_table) { 692 retval = EXT2_ET_MISSING_INODE_TABLE; 693 goto errout; 694 } 695 block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block; 696 697 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 698 699 length = EXT2_INODE_SIZE(fs->super); 700 if (length > bufsize) 701 length = bufsize; 702 703 ptr = (char *) w_inode; 704 705 while (length) { 706 clen = length; 707 if ((offset + length) > fs->blocksize) 708 clen = fs->blocksize - offset; 709 710 if (fs->icache->buffer_blk != block_nr) { 711 retval = io_channel_read_blk(fs->io, block_nr, 1, 712 fs->icache->buffer); 713 if (retval) 714 goto errout; 715 fs->icache->buffer_blk = block_nr; 716 } 717 718 719 memcpy((char *) fs->icache->buffer + (unsigned) offset, 720 ptr, clen); 721 722 retval = io_channel_write_blk(fs->io, block_nr, 1, 723 fs->icache->buffer); 724 if (retval) 725 goto errout; 726 727 offset = 0; 728 ptr += clen; 729 length -= clen; 730 block_nr++; 731 } 732 733 fs->flags |= EXT2_FLAG_CHANGED; 734 errout: 735 if (w_inode && w_inode != &temp_inode) 736 free(w_inode); 737 return retval; 738 } 739 740 errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino, 741 struct ext2_inode *inode) 742 { 743 return ext2fs_write_inode_full(fs, ino, inode, 744 sizeof(struct ext2_inode)); 745 } 746 747 /* 748 * This function should be called when writing a new inode. It makes 749 * sure that extra part of large inodes is initialized properly. 750 */ 751 errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino, 752 struct ext2_inode *inode) 753 { 754 struct ext2_inode *buf; 755 int size = EXT2_INODE_SIZE(fs->super); 756 struct ext2_inode_large *large_inode; 757 errcode_t retval; 758 __u32 t = fs->now ? fs->now : time(NULL); 759 760 if (!inode->i_ctime) 761 inode->i_ctime = t; 762 if (!inode->i_mtime) 763 inode->i_mtime = t; 764 if (!inode->i_atime) 765 inode->i_atime = t; 766 767 if (size == sizeof(struct ext2_inode)) 768 return ext2fs_write_inode_full(fs, ino, inode, 769 sizeof(struct ext2_inode)); 770 771 buf = malloc(size); 772 if (!buf) 773 return ENOMEM; 774 775 memset(buf, 0, size); 776 *buf = *inode; 777 778 large_inode = (struct ext2_inode_large *) buf; 779 large_inode->i_extra_isize = sizeof(struct ext2_inode_large) - 780 EXT2_GOOD_OLD_INODE_SIZE; 781 if (!large_inode->i_crtime) 782 large_inode->i_crtime = t; 783 784 retval = ext2fs_write_inode_full(fs, ino, buf, size); 785 free(buf); 786 return retval; 787 } 788 789 790 errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks) 791 { 792 struct ext2_inode inode; 793 int i; 794 errcode_t retval; 795 796 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 797 798 if (ino > fs->super->s_inodes_count) 799 return EXT2_ET_BAD_INODE_NUM; 800 801 if (fs->get_blocks) { 802 if (!(*fs->get_blocks)(fs, ino, blocks)) 803 return 0; 804 } 805 retval = ext2fs_read_inode(fs, ino, &inode); 806 if (retval) 807 return retval; 808 for (i=0; i < EXT2_N_BLOCKS; i++) 809 blocks[i] = inode.i_block[i]; 810 return 0; 811 } 812 813 errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino) 814 { 815 struct ext2_inode inode; 816 errcode_t retval; 817 818 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 819 820 if (ino > fs->super->s_inodes_count) 821 return EXT2_ET_BAD_INODE_NUM; 822 823 if (fs->check_directory) { 824 retval = (fs->check_directory)(fs, ino); 825 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 826 return retval; 827 } 828 retval = ext2fs_read_inode(fs, ino, &inode); 829 if (retval) 830 return retval; 831 if (!LINUX_S_ISDIR(inode.i_mode)) 832 return EXT2_ET_NO_DIRECTORY; 833 return 0; 834 } 835 836
