inode.c revision 1ed49d2c2ab7fdb02158d5feeb86288ece7eb17c
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_mem(sizeof(struct ext2_inode_cache_ent) 94 * fs->icache->cache_size, 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 retval = ext2fs_get_mem((size_t) (scan->inode_buffer_blocks * 150 fs->blocksize), 151 &scan->inode_buffer); 152 scan->done_group = 0; 153 scan->done_group_data = 0; 154 scan->bad_block_ptr = 0; 155 if (retval) { 156 ext2fs_free_mem(&scan); 157 return retval; 158 } 159 retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer); 160 if (retval) { 161 ext2fs_free_mem(&scan->inode_buffer); 162 ext2fs_free_mem(&scan); 163 return retval; 164 } 165 if (scan->fs->badblocks && scan->fs->badblocks->num) 166 scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS; 167 if (EXT2_HAS_COMPAT_FEATURE(fs->super, 168 EXT2_FEATURE_COMPAT_LAZY_BG)) 169 scan->scan_flags |= EXT2_SF_DO_LAZY; 170 *ret_scan = scan; 171 return 0; 172} 173 174void ext2fs_close_inode_scan(ext2_inode_scan scan) 175{ 176 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 177 return; 178 179 ext2fs_free_mem(&scan->inode_buffer); 180 scan->inode_buffer = NULL; 181 ext2fs_free_mem(&scan->temp_buffer); 182 scan->temp_buffer = NULL; 183 ext2fs_free_mem(&scan); 184 return; 185} 186 187void ext2fs_set_inode_callback(ext2_inode_scan scan, 188 errcode_t (*done_group)(ext2_filsys fs, 189 ext2_inode_scan scan, 190 dgrp_t group, 191 void * priv_data), 192 void *done_group_data) 193{ 194 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 195 return; 196 197 scan->done_group = done_group; 198 scan->done_group_data = done_group_data; 199} 200 201int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags, 202 int clear_flags) 203{ 204 int old_flags; 205 206 if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) 207 return 0; 208 209 old_flags = scan->scan_flags; 210 scan->scan_flags &= ~clear_flags; 211 scan->scan_flags |= set_flags; 212 return old_flags; 213} 214 215/* 216 * This function is called by ext2fs_get_next_inode when it needs to 217 * get ready to read in a new blockgroup. 218 */ 219static errcode_t get_next_blockgroup(ext2_inode_scan scan) 220{ 221 scan->current_group++; 222 scan->groups_left--; 223 224 scan->current_block = scan->fs-> 225 group_desc[scan->current_group].bg_inode_table; 226 227 scan->current_inode = scan->current_group * 228 EXT2_INODES_PER_GROUP(scan->fs->super); 229 230 scan->bytes_left = 0; 231 scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); 232 scan->blocks_left = scan->fs->inode_blocks_per_group; 233 return 0; 234} 235 236errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan, 237 int group) 238{ 239 scan->current_group = group - 1; 240 scan->groups_left = scan->fs->group_desc_count - group; 241 return get_next_blockgroup(scan); 242} 243 244/* 245 * This function is called by get_next_blocks() to check for bad 246 * blocks in the inode table. 247 * 248 * This function assumes that badblocks_list->list is sorted in 249 * increasing order. 250 */ 251static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan, 252 blk_t *num_blocks) 253{ 254 blk_t blk = scan->current_block; 255 badblocks_list bb = scan->fs->badblocks; 256 257 /* 258 * If the inode table is missing, then obviously there are no 259 * bad blocks. :-) 260 */ 261 if (blk == 0) 262 return 0; 263 264 /* 265 * If the current block is greater than the bad block listed 266 * in the bad block list, then advance the pointer until this 267 * is no longer the case. If we run out of bad blocks, then 268 * we don't need to do any more checking! 269 */ 270 while (blk > bb->list[scan->bad_block_ptr]) { 271 if (++scan->bad_block_ptr >= bb->num) { 272 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 273 return 0; 274 } 275 } 276 277 /* 278 * If the current block is equal to the bad block listed in 279 * the bad block list, then handle that one block specially. 280 * (We could try to handle runs of bad blocks, but that 281 * only increases CPU efficiency by a small amount, at the 282 * expense of a huge expense of code complexity, and for an 283 * uncommon case at that.) 284 */ 285 if (blk == bb->list[scan->bad_block_ptr]) { 286 scan->scan_flags |= EXT2_SF_BAD_INODE_BLK; 287 *num_blocks = 1; 288 if (++scan->bad_block_ptr >= bb->num) 289 scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; 290 return 0; 291 } 292 293 /* 294 * If there is a bad block in the range that we're about to 295 * read in, adjust the number of blocks to read so that we we 296 * don't read in the bad block. (Then the next block to read 297 * will be the bad block, which is handled in the above case.) 298 */ 299 if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr]) 300 *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk); 301 302 return 0; 303} 304 305/* 306 * This function is called by ext2fs_get_next_inode when it needs to 307 * read in more blocks from the current blockgroup's inode table. 308 */ 309static errcode_t get_next_blocks(ext2_inode_scan scan) 310{ 311 blk_t num_blocks; 312 errcode_t retval; 313 314 /* 315 * Figure out how many blocks to read; we read at most 316 * inode_buffer_blocks, and perhaps less if there aren't that 317 * many blocks left to read. 318 */ 319 num_blocks = scan->inode_buffer_blocks; 320 if (num_blocks > scan->blocks_left) 321 num_blocks = scan->blocks_left; 322 323 /* 324 * If the past block "read" was a bad block, then mark the 325 * left-over extra bytes as also being bad. 326 */ 327 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) { 328 if (scan->bytes_left) 329 scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES; 330 scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK; 331 } 332 333 /* 334 * Do inode bad block processing, if necessary. 335 */ 336 if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) { 337 retval = check_for_inode_bad_blocks(scan, &num_blocks); 338 if (retval) 339 return retval; 340 } 341 342 if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) || 343 (scan->current_block == 0)) { 344 memset(scan->inode_buffer, 0, 345 (size_t) num_blocks * scan->fs->blocksize); 346 } else { 347 retval = io_channel_read_blk(scan->fs->io, 348 scan->current_block, 349 (int) num_blocks, 350 scan->inode_buffer); 351 if (retval) 352 return EXT2_ET_NEXT_INODE_READ; 353 } 354 scan->ptr = scan->inode_buffer; 355 scan->bytes_left = num_blocks * scan->fs->blocksize; 356 357 scan->blocks_left -= num_blocks; 358 if (scan->current_block) 359 scan->current_block += num_blocks; 360 return 0; 361} 362 363#if 0 364/* 365 * Returns 1 if the entire inode_buffer has a non-zero size and 366 * contains all zeros. (Not just deleted inodes, since that means 367 * that part of the inode table was used at one point; we want all 368 * zeros, which means that the inode table is pristine.) 369 */ 370static inline int is_empty_scan(ext2_inode_scan scan) 371{ 372 int i; 373 374 if (scan->bytes_left == 0) 375 return 0; 376 377 for (i=0; i < scan->bytes_left; i++) 378 if (scan->ptr[i]) 379 return 0; 380 return 1; 381} 382#endif 383 384errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, 385 struct ext2_inode *inode, int bufsize) 386{ 387 errcode_t retval; 388 int extra_bytes = 0; 389 390 EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN); 391 392 /* 393 * Do we need to start reading a new block group? 394 */ 395 if (scan->inodes_left <= 0) { 396 force_new_group: 397 if (scan->done_group) { 398 retval = (scan->done_group) 399 (scan->fs, scan, scan->current_group, 400 scan->done_group_data); 401 if (retval) 402 return retval; 403 } 404 if (scan->groups_left <= 0) { 405 *ino = 0; 406 return 0; 407 } 408 retval = get_next_blockgroup(scan); 409 if (retval) 410 return retval; 411 } 412 /* 413 * These checks are done outside the above if statement so 414 * they can be done for block group #0. 415 */ 416 if ((scan->scan_flags & EXT2_SF_DO_LAZY) && 417 (scan->fs->group_desc[scan->current_group].bg_flags & 418 EXT2_BG_INODE_UNINIT)) 419 goto force_new_group; 420 if (scan->current_block == 0) { 421 if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) { 422 goto force_new_group; 423 } else 424 return EXT2_ET_MISSING_INODE_TABLE; 425 } 426 427 428 /* 429 * Have we run out of space in the inode buffer? If so, we 430 * need to read in more blocks. 431 */ 432 if (scan->bytes_left < scan->inode_size) { 433 memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left); 434 extra_bytes = scan->bytes_left; 435 436 retval = get_next_blocks(scan); 437 if (retval) 438 return retval; 439#if 0 440 /* 441 * XXX test Need check for used inode somehow. 442 * (Note: this is hard.) 443 */ 444 if (is_empty_scan(scan)) 445 goto force_new_group; 446#endif 447 } 448 449 retval = 0; 450 if (extra_bytes) { 451 memcpy(scan->temp_buffer+extra_bytes, scan->ptr, 452 scan->inode_size - extra_bytes); 453 scan->ptr += scan->inode_size - extra_bytes; 454 scan->bytes_left -= scan->inode_size - extra_bytes; 455 456#ifdef EXT2FS_ENABLE_SWAPFS 457 memset(inode, 0, bufsize); 458 if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) || 459 (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) 460 ext2fs_swap_inode_full(scan->fs, 461 (struct ext2_inode_large *) inode, 462 (struct ext2_inode_large *) scan->temp_buffer, 463 0, bufsize); 464 else 465#endif 466 *inode = *((struct ext2_inode *) scan->temp_buffer); 467 if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES) 468 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 469 scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES; 470 } else { 471#ifdef EXT2FS_ENABLE_SWAPFS 472 memset(inode, 0, bufsize); 473 if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) || 474 (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) 475 ext2fs_swap_inode_full(scan->fs, 476 (struct ext2_inode_large *) inode, 477 (struct ext2_inode_large *) scan->ptr, 478 0, bufsize); 479 else 480#endif 481 memcpy(inode, scan->ptr, bufsize); 482 scan->ptr += scan->inode_size; 483 scan->bytes_left -= scan->inode_size; 484 if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) 485 retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; 486 } 487 488 scan->inodes_left--; 489 scan->current_inode++; 490 *ino = scan->current_inode; 491 return retval; 492} 493 494errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino, 495 struct ext2_inode *inode) 496{ 497 return ext2fs_get_next_inode_full(scan, ino, inode, 498 sizeof(struct ext2_inode)); 499} 500 501/* 502 * Functions to read and write a single inode. 503 */ 504errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, 505 struct ext2_inode * inode, int bufsize) 506{ 507 unsigned long group, block, block_nr, offset; 508 char *ptr; 509 errcode_t retval; 510 int clen, i, inodes_per_block, length; 511 io_channel io; 512 513 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 514 515 /* Check to see if user has an override function */ 516 if (fs->read_inode) { 517 retval = (fs->read_inode)(fs, ino, inode); 518 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 519 return retval; 520 } 521 /* Create inode cache if not present */ 522 if (!fs->icache) { 523 retval = create_icache(fs); 524 if (retval) 525 return retval; 526 } 527 /* Check to see if it's in the inode cache */ 528 if (bufsize == sizeof(struct ext2_inode)) { 529 /* only old good inode can be retrieve from the cache */ 530 for (i=0; i < fs->icache->cache_size; i++) { 531 if (fs->icache->cache[i].ino == ino) { 532 *inode = fs->icache->cache[i].inode; 533 return 0; 534 } 535 } 536 } 537 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 538 return EXT2_ET_BAD_INODE_NUM; 539 if (fs->flags & EXT2_FLAG_IMAGE_FILE) { 540 inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); 541 block_nr = fs->image_header->offset_inode / fs->blocksize; 542 block_nr += (ino - 1) / inodes_per_block; 543 offset = ((ino - 1) % inodes_per_block) * 544 EXT2_INODE_SIZE(fs->super); 545 io = fs->image_io; 546 } else { 547 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 548 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 549 EXT2_INODE_SIZE(fs->super); 550 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 551 if (!fs->group_desc[(unsigned)group].bg_inode_table) 552 return EXT2_ET_MISSING_INODE_TABLE; 553 block_nr = fs->group_desc[(unsigned)group].bg_inode_table + 554 block; 555 io = fs->io; 556 } 557 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 558 559 length = EXT2_INODE_SIZE(fs->super); 560 if (bufsize < length) 561 length = bufsize; 562 563 ptr = (char *) inode; 564 while (length) { 565 clen = length; 566 if ((offset + length) > fs->blocksize) 567 clen = fs->blocksize - offset; 568 569 if (block_nr != fs->icache->buffer_blk) { 570 retval = io_channel_read_blk(io, block_nr, 1, 571 fs->icache->buffer); 572 if (retval) 573 return retval; 574 fs->icache->buffer_blk = block_nr; 575 } 576 577 memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset, 578 clen); 579 580 offset = 0; 581 length -= clen; 582 ptr += clen; 583 block_nr++; 584 } 585 586#ifdef EXT2FS_ENABLE_SWAPFS 587 if ((fs->flags & EXT2_FLAG_SWAP_BYTES) || 588 (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) 589 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode, 590 (struct ext2_inode_large *) inode, 591 0, bufsize); 592#endif 593 594 /* Update the inode cache */ 595 fs->icache->cache_last = (fs->icache->cache_last + 1) % 596 fs->icache->cache_size; 597 fs->icache->cache[fs->icache->cache_last].ino = ino; 598 fs->icache->cache[fs->icache->cache_last].inode = *inode; 599 600 return 0; 601} 602 603errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino, 604 struct ext2_inode * inode) 605{ 606 return ext2fs_read_inode_full(fs, ino, inode, 607 sizeof(struct ext2_inode)); 608} 609 610errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, 611 struct ext2_inode * inode, int bufsize) 612{ 613 unsigned long group, block, block_nr, offset; 614 errcode_t retval = 0; 615 struct ext2_inode_large temp_inode, *w_inode; 616 char *ptr; 617 int clen, i, length; 618 619 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 620 621 /* Check to see if user provided an override function */ 622 if (fs->write_inode) { 623 retval = (fs->write_inode)(fs, ino, inode); 624 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 625 return retval; 626 } 627 628 /* Check to see if the inode cache needs to be updated */ 629 if (fs->icache) { 630 for (i=0; i < fs->icache->cache_size; i++) { 631 if (fs->icache->cache[i].ino == ino) { 632 fs->icache->cache[i].inode = *inode; 633 break; 634 } 635 } 636 } else { 637 retval = create_icache(fs); 638 if (retval) 639 return retval; 640 } 641 642 if (!(fs->flags & EXT2_FLAG_RW)) 643 return EXT2_ET_RO_FILSYS; 644 645 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 646 return EXT2_ET_BAD_INODE_NUM; 647 648 length = bufsize; 649 if (length < EXT2_INODE_SIZE(fs->super)) 650 length = EXT2_INODE_SIZE(fs->super); 651 652 if (length > (int) sizeof(struct ext2_inode_large)) { 653 w_inode = malloc(length); 654 if (!w_inode) 655 return ENOMEM; 656 } else 657 w_inode = &temp_inode; 658 memset(w_inode, 0, length); 659 660#ifdef EXT2FS_ENABLE_SWAPFS 661 if ((fs->flags & EXT2_FLAG_SWAP_BYTES) || 662 (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)) 663 ext2fs_swap_inode_full(fs, w_inode, 664 (struct ext2_inode_large *) inode, 665 1, bufsize); 666 else 667#endif 668 memcpy(w_inode, inode, bufsize); 669 670 group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); 671 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * 672 EXT2_INODE_SIZE(fs->super); 673 block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); 674 if (!fs->group_desc[(unsigned) group].bg_inode_table) { 675 retval = EXT2_ET_MISSING_INODE_TABLE; 676 goto errout; 677 } 678 block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block; 679 680 offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); 681 682 length = EXT2_INODE_SIZE(fs->super); 683 if (length > bufsize) 684 length = bufsize; 685 686 ptr = (char *) w_inode; 687 688 while (length) { 689 clen = length; 690 if ((offset + length) > fs->blocksize) 691 clen = fs->blocksize - offset; 692 693 if (fs->icache->buffer_blk != block_nr) { 694 retval = io_channel_read_blk(fs->io, block_nr, 1, 695 fs->icache->buffer); 696 if (retval) 697 goto errout; 698 fs->icache->buffer_blk = block_nr; 699 } 700 701 702 memcpy((char *) fs->icache->buffer + (unsigned) offset, 703 ptr, clen); 704 705 retval = io_channel_write_blk(fs->io, block_nr, 1, 706 fs->icache->buffer); 707 if (retval) 708 goto errout; 709 710 offset = 0; 711 ptr += clen; 712 length -= clen; 713 block_nr++; 714 } 715 716 fs->flags |= EXT2_FLAG_CHANGED; 717errout: 718 if (w_inode && w_inode != &temp_inode) 719 free(w_inode); 720 return retval; 721} 722 723errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino, 724 struct ext2_inode *inode) 725{ 726 return ext2fs_write_inode_full(fs, ino, inode, 727 sizeof(struct ext2_inode)); 728} 729 730/* 731 * This function should be called when writing a new inode. It makes 732 * sure that extra part of large inodes is initialized properly. 733 */ 734errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino, 735 struct ext2_inode *inode) 736{ 737 struct ext2_inode *buf; 738 int size = EXT2_INODE_SIZE(fs->super); 739 struct ext2_inode_large *large_inode; 740 errcode_t retval; 741 742 if (size == sizeof(struct ext2_inode)) 743 return ext2fs_write_inode_full(fs, ino, inode, 744 sizeof(struct ext2_inode)); 745 746 buf = malloc(size); 747 if (!buf) 748 return ENOMEM; 749 750 memset(buf, 0, size); 751 *buf = *inode; 752 753 large_inode = (struct ext2_inode_large *) buf; 754 large_inode->i_extra_isize = sizeof(struct ext2_inode_large) - 755 EXT2_GOOD_OLD_INODE_SIZE; 756 757 retval = ext2fs_write_inode_full(fs, ino, buf, size); 758 free(buf); 759 return retval; 760} 761 762 763errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks) 764{ 765 struct ext2_inode inode; 766 int i; 767 errcode_t retval; 768 769 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 770 771 if (ino > fs->super->s_inodes_count) 772 return EXT2_ET_BAD_INODE_NUM; 773 774 if (fs->get_blocks) { 775 if (!(*fs->get_blocks)(fs, ino, blocks)) 776 return 0; 777 } 778 retval = ext2fs_read_inode(fs, ino, &inode); 779 if (retval) 780 return retval; 781 for (i=0; i < EXT2_N_BLOCKS; i++) 782 blocks[i] = inode.i_block[i]; 783 return 0; 784} 785 786errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino) 787{ 788 struct ext2_inode inode; 789 errcode_t retval; 790 791 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 792 793 if (ino > fs->super->s_inodes_count) 794 return EXT2_ET_BAD_INODE_NUM; 795 796 if (fs->check_directory) { 797 retval = (fs->check_directory)(fs, ino); 798 if (retval != EXT2_ET_CALLBACK_NOTHANDLED) 799 return retval; 800 } 801 retval = ext2fs_read_inode(fs, ino, &inode); 802 if (retval) 803 return retval; 804 if (!LINUX_S_ISDIR(inode.i_mode)) 805 return EXT2_ET_NO_DIRECTORY; 806 return 0; 807} 808 809