inode.c revision 3bcc6276a0c229791ca4a4fee4cf6d8d48ebe824
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#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 "ext2fsP.h" 29#include "e2image.h" 30 31struct ext2_struct_inode_scan { 32 errcode_t magic; 33 ext2_filsys fs; 34 ext2_ino_t current_inode; 35 blk_t current_block; 36 dgrp_t current_group; 37 ext2_ino_t inodes_left; 38 blk_t blocks_left; 39 dgrp_t groups_left; 40 blk_t inode_buffer_blocks; 41 char * inode_buffer; 42 int inode_size; 43 char * ptr; 44 int bytes_left; 45 char *temp_buffer; 46 errcode_t (*done_group)(ext2_filsys fs, 47 ext2_inode_scan scan, 48 dgrp_t group, 49 void * priv_data); 50 void * done_group_data; 51 int bad_block_ptr; 52 int scan_flags; 53 int reserved[6]; 54}; 55 56/* 57 * This routine flushes the icache, if it exists. 58 */ 59errcode_t ext2fs_flush_icache(ext2_filsys fs) 60{ 61 int i; 62 63 if (!fs->icache) 64 return 0; 65 66 for (i=0; i < fs->icache->cache_size; i++) 67 fs->icache->cache[i].ino = 0; 68 69 fs->icache->buffer_blk = 0; 70 return 0; 71} 72 73static errcode_t create_icache(ext2_filsys fs) 74{ 75 errcode_t retval; 76 77 if (fs->icache) 78 return 0; 79 retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache); 80 if (retval) 81 return retval; 82 83 memset(fs->icache, 0, sizeof(struct ext2_inode_cache)); 84 retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer); 85 if (retval) { 86 ext2fs_free_mem(&fs->icache); 87 return retval; 88 } 89 fs->icache->buffer_blk = 0; 90 fs->icache->cache_last = -1; 91 fs->icache->cache_size = 4; 92 fs->icache->refcount = 1; 93 retval = ext2fs_get_array(fs->icache->cache_size, 94 sizeof(struct ext2_inode_cache_ent), 95 &fs->icache->cache); 96 if (retval) { 97 ext2fs_free_mem(&fs->icache->buffer); 98 ext2fs_free_mem(&fs->icache); 99 return retval; 100 } 101 ext2fs_flush_icache(fs); 102 return 0; 103} 104 105errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks, 106 ext2_inode_scan *ret_scan) 107{ 108 ext2_inode_scan scan; 109 errcode_t retval; 110 errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks); 111 112 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 113 114 /* 115 * If fs->badblocks isn't set, then set it --- since the inode 116 * scanning functions require it. 117 */ 118 if (fs->badblocks == 0) { 119 /* 120 * Temporarly save fs->get_blocks and set it to zero, 121 * for compatibility with old e2fsck's. 122 */ 123 save_get_blocks = fs->get_blocks; 124 fs->get_blocks = 0; 125 retval = ext2fs_read_bb_inode(fs, &fs->badblocks); 126 if (retval && fs->badblocks) { 127 ext2fs_badblocks_list_free(fs->badblocks); 128 fs->badblocks = 0; 129 } 130 fs->get_blocks = save_get_blocks; 131 } 132 133 retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan); 134 if (retval) 135 return retval; 136 memset(scan, 0, sizeof(struct ext2_struct_inode_scan)); 137 138 scan->magic = EXT2_ET_MAGIC_INODE_SCAN; 139 scan->fs = fs; 140 scan->inode_size = EXT2_INODE_SIZE(fs->super); 141 scan->bytes_left = 0; 142 scan->current_group = 0; 143 scan->groups_left = fs->group_desc_count - 1; 144 scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8; 145 scan->current_block = scan->fs-> 146 group_desc[scan->current_group].bg_inode_table; 147 scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); 148 scan->blocks_left = scan->fs->inode_blocks_per_group; 149 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 150 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { 151 scan->inodes_left -= 152 fs->group_desc[scan->current_group].bg_itable_unused; 153 scan->blocks_left = 154 (scan->inodes_left + 155 (fs->blocksize / scan->inode_size - 1)) * 156 scan->inode_size / fs->blocksize; 157 } 158 retval = ext2fs_get_array(scan->inode_buffer_blocks, 159 fs->blocksize, 160 &scan->inode_buffer); 161 scan->done_group = 0; 162 scan->done_group_data = 0; 163 scan->bad_block_ptr = 0; 164 if (retval) { 165 ext2fs_free_mem(&scan); 166 return retval; 167 } 168 retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer); 169 if (retval) { 170 ext2fs_free_mem(&scan->inode_buffer); 171 ext2fs_free_mem(&scan); 172 return retval; 173 } 174 if (scan->fs->badblocks && scan->fs->badblocks->num) 175 scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS; 176 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 177 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) 178 scan->scan_flags |= EXT2_SF_DO_LAZY; 179 *ret_scan = scan; 180 return 0; 181} 182 183void ext2fs_close_inode_scan(ext2_inode_scan scan) 184{ 185 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 186 return; 187 188 ext2fs_free_mem(&scan->inode_buffer); 189 scan->inode_buffer = NULL; 190 ext2fs_free_mem(&scan->temp_buffer); 191 scan->temp_buffer = NULL; 192 ext2fs_free_mem(&scan); 193 return; 194} 195 196void ext2fs_set_inode_callback(ext2_inode_scan scan, 197 errcode_t (*done_group)(ext2_filsys fs, 198 ext2_inode_scan scan, 199 dgrp_t group, 200 void * priv_data), 201 void *done_group_data) 202{ 203 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 204 return; 205 206 scan->done_group = done_group; 207 scan->done_group_data = done_group_data; 208} 209 210int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags, 211 int clear_flags) 212{ 213 int old_flags; 214 215 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 216 return 0; 217 218 old_flags = scan->scan_flags; 219 scan->scan_flags &= ~clear_flags; 220 scan->scan_flags |= set_flags; 221 return old_flags; 222} 223 224/* 225 * This function is called by ext2fs_get_next_inode when it needs to 226 * get ready to read in a new blockgroup. 227 */ 228static errcode_t get_next_blockgroup(ext2_inode_scan scan) 229{ 230 ext2_filsys fs = scan->fs; 231 232 scan->current_group++; 233 scan->groups_left--; 234 235 scan->current_block =fs->group_desc[scan->current_group].bg_inode_table; 236 237 scan->current_inode = scan->current_group * 238 EXT2_INODES_PER_GROUP(fs->super); 239 240 scan->bytes_left = 0; 241 scan->inodes_left = EXT2_INODES_PER_GROUP(fs->super); 242 scan->blocks_left = fs->inode_blocks_per_group; 243 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, 244 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { 245 scan->inodes_left -= 246 fs->group_desc[scan->current_group].bg_itable_unused; 247 scan->blocks_left = 248 (scan->inodes_left + 249 (fs->blocksize / scan->inode_size - 1)) * 250 scan->inode_size / fs->blocksize; 251 } 252 253 return 0; 254} 255 256errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan, 257 int group) 258{ 259 scan->current_group = group - 1; 260 scan->groups_left = scan->fs->group_desc_count - group; 261 return get_next_blockgroup(scan); 262} 263 264/* 265 * This function is called by get_next_blocks() to check for bad 266 * blocks in the inode table. 267 * 268 * This function assumes that badblocks_list->list is sorted in 269 * increasing order. 270 */ 271static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan, 272 blk_t *num_blocks) 273{ 274 blk_t blk = scan->current_block; 275 badblocks_list bb = scan->fs->badblocks; 276 277 /* 278 * If the inode table is missing, then obviously there are no 279 * bad blocks. :-) 280 */ 281 if (blk == 0) 282 return 0; 283 284 /* 285 * If the current block is greater than the bad block listed 286 * in the bad block list, then advance the pointer until this 287 * is no longer the case. If we run out of bad blocks, then 288 * we don't need to do any more checking! 289 */ 290 while (blk > bb->list[scan->bad_block_ptr]) { 291 if (++scan->bad_block_ptr >= bb->num) { 292 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 293 return 0; 294 } 295 } 296 297 /* 298 * If the current block is equal to the bad block listed in 299 * the bad block list, then handle that one block specially. 300 * (We could try to handle runs of bad blocks, but that 301 * only increases CPU efficiency by a small amount, at the 302 * expense of a huge expense of code complexity, and for an 303 * uncommon case at that.) 304 */ 305 if (blk == bb->list[scan->bad_block_ptr]) { 306 scan->scan_flags |= EXT2_SF_BAD_INODE_BLK; 307 *num_blocks = 1; 308 if (++scan->bad_block_ptr >= bb->num) 309 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 310 return 0; 311 } 312 313 /* 314 * If there is a bad block in the range that we're about to 315 * read in, adjust the number of blocks to read so that we we 316 * don't read in the bad block. (Then the next block to read 317 * will be the bad block, which is handled in the above case.) 318 */ 319 if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr]) 320 *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk); 321 322 return 0; 323} 324 325/* 326 * This function is called by ext2fs_get_next_inode when it needs to 327 * read in more blocks from the current blockgroup's inode table. 328 */ 329static errcode_t get_next_blocks(ext2_inode_scan scan) 330{ 331 blk_t num_blocks; 332 errcode_t retval; 333 334 /* 335 * Figure out how many blocks to read; we read at most 336 * inode_buffer_blocks, and perhaps less if there aren't that 337 * many blocks left to read. 338 */ 339 num_blocks = scan->inode_buffer_blocks; 340 if (num_blocks > scan->blocks_left) 341 num_blocks = scan->blocks_left; 342 343 /* 344 * If the past block "read" was a bad block, then mark the 345 * left-over extra bytes as also being bad. 346 */ 347 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) { 348 if (scan->bytes_left) 349 scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES; 350 scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK; 351 } 352 353 /* 354 * Do inode bad block processing, if necessary. 355 */ 356 if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) { 357 retval = check_for_inode_bad_blocks(scan, &num_blocks); 358 if (retval) 359 return retval; 360 } 361 362 if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) || 363 (scan->current_block == 0)) { 364 memset(scan->inode_buffer, 0, 365 (size_t) num_blocks * scan->fs->blocksize); 366 } else { 367 retval = io_channel_read_blk(scan->fs->io, 368 scan->current_block, 369 (int) num_blocks, 370 scan->inode_buffer); 371 if (retval) 372 return EXT2_ET_NEXT_INODE_READ; 373 } 374 scan->ptr = scan->inode_buffer; 375 scan->bytes_left = num_blocks * scan->fs->blocksize; 376 377 scan->blocks_left -= num_blocks; 378 if (scan->current_block) 379 scan->current_block += num_blocks; 380 return 0; 381} 382 383#if 0 384/* 385 * Returns 1 if the entire inode_buffer has a non-zero size and 386 * contains all zeros. (Not just deleted inodes, since that means 387 * that part of the inode table was used at one point; we want all 388 * zeros, which means that the inode table is pristine.) 389 */ 390static inline int is_empty_scan(ext2_inode_scan scan) 391{ 392 int i; 393 394 if (scan->bytes_left == 0) 395 return 0; 396 397 for (i=0; i < scan->bytes_left; i++) 398 if (scan->ptr[i]) 399 return 0; 400 return 1; 401} 402#endif 403 404errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, 405 struct ext2_inode *inode, int bufsize) 406{ 407 errcode_t retval; 408 int extra_bytes = 0; 409 410 EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN); 411 412 /* 413 * Do we need to start reading a new block group? 414 */ 415 if (scan->inodes_left <= 0) { 416 force_new_group: 417 if (scan->done_group) { 418 retval = (scan->done_group) 419 (scan->fs, scan, scan->current_group, 420 scan->done_group_data); 421 if (retval) 422 return retval; 423 } 424 if (scan->groups_left <= 0) { 425 *ino = 0; 426 return 0; 427 } 428 retval = get_next_blockgroup(scan); 429 if (retval) 430 return retval; 431 } 432 /* 433 * These checks are done outside the above if statement so 434 * they can be done for block group #0. 435 */ 436 if ((scan->scan_flags & EXT2_SF_DO_LAZY) && 437 (scan->fs->group_desc[scan->current_group].bg_flags & 438 EXT2_BG_INODE_UNINIT)) 439 goto force_new_group; 440 if (scan->inodes_left == 0) 441 goto force_new_group; 442 if (scan->current_block == 0) { 443 if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) { 444 goto force_new_group; 445 } else 446 return EXT2_ET_MISSING_INODE_TABLE; 447 } 448 449 450 /* 451 * Have we run out of space in the inode buffer? If so, we 452 * need to read in more blocks. 453 */ 454 if (scan->bytes_left < scan->inode_size) { 455 memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left); 456 extra_bytes = scan->bytes_left; 457 458 retval = get_next_blocks(scan); 459 if (retval) 460 return retval; 461#if 0 462 /* 463 * XXX test Need check for used inode somehow. 464 * (Note: this is hard.) 465 */ 466 if (is_empty_scan(scan)) 467 goto force_new_group; 468#endif 469 } 470 471 retval = 0; 472 if (extra_bytes) { 473 memcpy(scan->temp_buffer+extra_bytes, scan->ptr, 474 scan->inode_size - extra_bytes); 475 scan->ptr += scan->inode_size - extra_bytes; 476 scan->bytes_left -= scan->inode_size - extra_bytes; 477 478#ifdef WORDS_BIGENDIAN 479 memset(inode, 0, bufsize); 480 ext2fs_swap_inode_full(scan->fs, 481 (struct ext2_inode_large *) inode, 482 (struct ext2_inode_large *) scan->temp_buffer, 483 0, bufsize); 484#else 485 *inode = *((struct ext2_inode *) scan->temp_buffer); 486#endif 487 if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES) 488 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 489 scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES; 490 } else { 491#ifdef WORDS_BIGENDIAN 492 memset(inode, 0, bufsize); 493 ext2fs_swap_inode_full(scan->fs, 494 (struct ext2_inode_large *) inode, 495 (struct ext2_inode_large *) scan->ptr, 496 0, bufsize); 497#else 498 memcpy(inode, scan->ptr, bufsize); 499#endif 500 scan->ptr += scan->inode_size; 501 scan->bytes_left -= scan->inode_size; 502 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) 503 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 504 } 505 506 scan->inodes_left--; 507 scan->current_inode++; 508 *ino = scan->current_inode; 509 return retval; 510} 511 512errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino, 513 struct ext2_inode *inode) 514{ 515 return ext2fs_get_next_inode_full(scan, ino, inode, 516 sizeof(struct ext2_inode)); 517} 518 519/* 520 * Functions to read and write a single inode. 521 */ 522errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, 523 struct ext2_inode * inode, int bufsize) 524{ 525 unsigned long group, block, block_nr, offset; 526 char *ptr; 527 errcode_t retval; 528 int clen, i, inodes_per_block, length; 529 io_channel io; 530 531 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 532 533 /* Check to see if user has an override function */ 534 if (fs->read_inode) { 535 retval = (fs->read_inode)(fs, ino, inode); 536 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 537 return retval; 538 } 539 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 540 return EXT2_ET_BAD_INODE_NUM; 541 /* Create inode cache if not present */ 542 if (!fs->icache) { 543 retval = create_icache(fs); 544 if (retval) 545 return retval; 546 } 547 /* Check to see if it's in the inode cache */ 548 if (bufsize == sizeof(struct ext2_inode)) { 549 /* only old good inode can be retrieved from the cache */ 550 for (i=0; i < fs->icache->cache_size; i++) { 551 if (fs->icache->cache[i].ino == ino) { 552 *inode = fs->icache->cache[i].inode; 553 return 0; 554 } 555 } 556 } 557 if (fs->flags & EXT2_FLAG_IMAGE_FILE) { 558 inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); 559 block_nr = fs->image_header->offset_inode / fs->blocksize; 560 block_nr += (ino - 1) / inodes_per_block; 561 offset = ((ino - 1) % inodes_per_block) * 562 EXT2_INODE_SIZE(fs->super); 563 io = fs->image_io; 564 } else { 565 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 566 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 567 EXT2_INODE_SIZE(fs->super); 568 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 569 if (!fs->group_desc[(unsigned)group].bg_inode_table) 570 return EXT2_ET_MISSING_INODE_TABLE; 571 block_nr = fs->group_desc[(unsigned)group].bg_inode_table + 572 block; 573 io = fs->io; 574 } 575 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 576 577 length = EXT2_INODE_SIZE(fs->super); 578 if (bufsize < length) 579 length = bufsize; 580 581 ptr = (char *) inode; 582 while (length) { 583 clen = length; 584 if ((offset + length) > fs->blocksize) 585 clen = fs->blocksize - offset; 586 587 if (block_nr != fs->icache->buffer_blk) { 588 retval = io_channel_read_blk(io, block_nr, 1, 589 fs->icache->buffer); 590 if (retval) 591 return retval; 592 fs->icache->buffer_blk = block_nr; 593 } 594 595 memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset, 596 clen); 597 598 offset = 0; 599 length -= clen; 600 ptr += clen; 601 block_nr++; 602 } 603 604#ifdef WORDS_BIGENDIAN 605 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode, 606 (struct ext2_inode_large *) inode, 607 0, bufsize); 608#endif 609 610 /* Update the inode cache */ 611 fs->icache->cache_last = (fs->icache->cache_last + 1) % 612 fs->icache->cache_size; 613 fs->icache->cache[fs->icache->cache_last].ino = ino; 614 fs->icache->cache[fs->icache->cache_last].inode = *inode; 615 616 return 0; 617} 618 619errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino, 620 struct ext2_inode * inode) 621{ 622 return ext2fs_read_inode_full(fs, ino, inode, 623 sizeof(struct ext2_inode)); 624} 625 626errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, 627 struct ext2_inode * inode, int bufsize) 628{ 629 unsigned long group, block, block_nr, offset; 630 errcode_t retval = 0; 631 struct ext2_inode_large temp_inode, *w_inode; 632 char *ptr; 633 int clen, i, length; 634 635 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 636 637 /* Check to see if user provided an override function */ 638 if (fs->write_inode) { 639 retval = (fs->write_inode)(fs, ino, inode); 640 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 641 return retval; 642 } 643 644 /* Check to see if the inode cache needs to be updated */ 645 if (fs->icache) { 646 for (i=0; i < fs->icache->cache_size; i++) { 647 if (fs->icache->cache[i].ino == ino) { 648 fs->icache->cache[i].inode = *inode; 649 break; 650 } 651 } 652 } else { 653 retval = create_icache(fs); 654 if (retval) 655 return retval; 656 } 657 658 if (!(fs->flags & EXT2_FLAG_RW)) 659 return EXT2_ET_RO_FILSYS; 660 661 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 662 return EXT2_ET_BAD_INODE_NUM; 663 664 length = bufsize; 665 if (length < EXT2_INODE_SIZE(fs->super)) 666 length = EXT2_INODE_SIZE(fs->super); 667 668 if (length > (int) sizeof(struct ext2_inode_large)) { 669 w_inode = malloc(length); 670 if (!w_inode) 671 return ENOMEM; 672 } else 673 w_inode = &temp_inode; 674 memset(w_inode, 0, length); 675 676#ifdef WORDS_BIGENDIAN 677 ext2fs_swap_inode_full(fs, w_inode, 678 (struct ext2_inode_large *) inode, 679 1, bufsize); 680#else 681 memcpy(w_inode, inode, bufsize); 682#endif 683 684 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 685 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 686 EXT2_INODE_SIZE(fs->super); 687 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 688 if (!fs->group_desc[(unsigned) group].bg_inode_table) { 689 retval = EXT2_ET_MISSING_INODE_TABLE; 690 goto errout; 691 } 692 block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block; 693 694 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 695 696 length = EXT2_INODE_SIZE(fs->super); 697 if (length > bufsize) 698 length = bufsize; 699 700 ptr = (char *) w_inode; 701 702 while (length) { 703 clen = length; 704 if ((offset + length) > fs->blocksize) 705 clen = fs->blocksize - offset; 706 707 if (fs->icache->buffer_blk != block_nr) { 708 retval = io_channel_read_blk(fs->io, block_nr, 1, 709 fs->icache->buffer); 710 if (retval) 711 goto errout; 712 fs->icache->buffer_blk = block_nr; 713 } 714 715 716 memcpy((char *) fs->icache->buffer + (unsigned) offset, 717 ptr, clen); 718 719 retval = io_channel_write_blk(fs->io, block_nr, 1, 720 fs->icache->buffer); 721 if (retval) 722 goto errout; 723 724 offset = 0; 725 ptr += clen; 726 length -= clen; 727 block_nr++; 728 } 729 730 fs->flags |= EXT2_FLAG_CHANGED; 731errout: 732 if (w_inode && w_inode != &temp_inode) 733 free(w_inode); 734 return retval; 735} 736 737errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino, 738 struct ext2_inode *inode) 739{ 740 return ext2fs_write_inode_full(fs, ino, inode, 741 sizeof(struct ext2_inode)); 742} 743 744/* 745 * This function should be called when writing a new inode. It makes 746 * sure that extra part of large inodes is initialized properly. 747 */ 748errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino, 749 struct ext2_inode *inode) 750{ 751 struct ext2_inode *buf; 752 int size = EXT2_INODE_SIZE(fs->super); 753 struct ext2_inode_large *large_inode; 754 errcode_t retval; 755 __u32 t = fs->now ? fs->now : time(NULL); 756 757 if (!inode->i_ctime) 758 inode->i_ctime = t; 759 if (!inode->i_mtime) 760 inode->i_mtime = t; 761 if (!inode->i_atime) 762 inode->i_atime = t; 763 764 if (size == sizeof(struct ext2_inode)) 765 return ext2fs_write_inode_full(fs, ino, inode, 766 sizeof(struct ext2_inode)); 767 768 buf = malloc(size); 769 if (!buf) 770 return ENOMEM; 771 772 memset(buf, 0, size); 773 *buf = *inode; 774 775 large_inode = (struct ext2_inode_large *) buf; 776 large_inode->i_extra_isize = sizeof(struct ext2_inode_large) - 777 EXT2_GOOD_OLD_INODE_SIZE; 778 if (!large_inode->i_crtime) 779 large_inode->i_crtime = t; 780 781 retval = ext2fs_write_inode_full(fs, ino, buf, size); 782 free(buf); 783 return retval; 784} 785 786 787errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks) 788{ 789 struct ext2_inode inode; 790 int i; 791 errcode_t retval; 792 793 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 794 795 if (ino > fs->super->s_inodes_count) 796 return EXT2_ET_BAD_INODE_NUM; 797 798 if (fs->get_blocks) { 799 if (!(*fs->get_blocks)(fs, ino, blocks)) 800 return 0; 801 } 802 retval = ext2fs_read_inode(fs, ino, &inode); 803 if (retval) 804 return retval; 805 for (i=0; i < EXT2_N_BLOCKS; i++) 806 blocks[i] = inode.i_block[i]; 807 return 0; 808} 809 810errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino) 811{ 812 struct ext2_inode inode; 813 errcode_t retval; 814 815 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 816 817 if (ino > fs->super->s_inodes_count) 818 return EXT2_ET_BAD_INODE_NUM; 819 820 if (fs->check_directory) { 821 retval = (fs->check_directory)(fs, ino); 822 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 823 return retval; 824 } 825 retval = ext2fs_read_inode(fs, ino, &inode); 826 if (retval) 827 return retval; 828 if (!LINUX_S_ISDIR(inode.i_mode)) 829 return EXT2_ET_NO_DIRECTORY; 830 return 0; 831} 832 833