source: mainline/uspace/lib/ext4/libext4_filesystem.c@ fe56c08a

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since fe56c08a was 304faab, checked in by Frantisek Princ <frantisek.princ@…>, 13 years ago

Very simple allocation algorithm
  • Property mode set to 100644
File size: 21.0 KB
Line 
1/*
2 * Copyright (c) 2011 Frantisek Princ
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup libext4
30 * @{
31 */
32
33/**
34 * @file libext4_filesystem.c
35 * @brief TODO
36 */
37
38#include <byteorder.h>
39#include <errno.h>
40#include <malloc.h>
41#include "libext4.h"
42
43int ext4_filesystem_init(ext4_filesystem_t *fs, service_id_t service_id)
44{
45 int rc;
46
47 fs->device = service_id;
48
49 // TODO what does constant 2048 mean?
50 rc = block_init(EXCHANGE_SERIALIZE, fs->device, 2048);
51 if (rc != EOK) {
52 return rc;
53 }
54
55 /* Read superblock from device */
56 ext4_superblock_t *temp_superblock;
57 rc = ext4_superblock_read_direct(fs->device, &temp_superblock);
58 if (rc != EOK) {
59 block_fini(fs->device);
60 return rc;
61 }
62
63 /* Read block size from superblock and check */
64 uint32_t block_size = ext4_superblock_get_block_size(temp_superblock);
65 if (block_size > EXT4_MAX_BLOCK_SIZE) {
66 block_fini(fs->device);
67 return ENOTSUP;
68 }
69
70 /* Initialize block caching */
71 rc = block_cache_init(service_id, block_size, 0, CACHE_MODE_WT);
72 if (rc != EOK) {
73 block_fini(fs->device);
74 return rc;
75 }
76
77 uint32_t block_ids_per_block = block_size / sizeof(uint32_t);
78 fs->inode_block_limits[0] = EXT4_INODE_DIRECT_BLOCK_COUNT;
79 fs->inode_blocks_per_level[0] = 1;
80 for (int i = 1; i < 4; i++) {
81 fs->inode_blocks_per_level[i] = fs->inode_blocks_per_level[i-1] *
82 block_ids_per_block;
83 fs->inode_block_limits[i] = fs->inode_block_limits[i-1] +
84 fs->inode_blocks_per_level[i];
85 }
86
87 /* Return loaded superblock */
88 fs->superblock = temp_superblock;
89
90 return EOK;
91}
92
93int ext4_filesystem_fini(ext4_filesystem_t *fs, bool write_sb)
94{
95 int rc = EOK;
96
97 if (write_sb) {
98 rc = ext4_superblock_write_direct(fs->device, fs->superblock);
99 }
100
101 free(fs->superblock);
102 block_fini(fs->device);
103
104 return rc;
105}
106
107int ext4_filesystem_check_sanity(ext4_filesystem_t *fs)
108{
109 int rc;
110
111 rc = ext4_superblock_check_sanity(fs->superblock);
112 if (rc != EOK) {
113 return rc;
114 }
115
116 return EOK;
117}
118
119int ext4_filesystem_check_features(ext4_filesystem_t *fs, bool *o_read_only)
120{
121 /* Feature flags are present in rev 1 and later */
122 if (ext4_superblock_get_rev_level(fs->superblock) == 0) {
123 *o_read_only = false;
124 return EOK;
125 }
126
127 uint32_t incompatible_features;
128 incompatible_features = ext4_superblock_get_features_incompatible(fs->superblock);
129 incompatible_features &= ~EXT4_FEATURE_INCOMPAT_SUPP;
130 if (incompatible_features > 0) {
131 *o_read_only = true;
132 return ENOTSUP;
133 }
134
135 uint32_t compatible_read_only;
136 compatible_read_only = ext4_superblock_get_features_read_only(fs->superblock);
137 compatible_read_only &= ~EXT4_FEATURE_RO_COMPAT_SUPP;
138 if (compatible_read_only > 0) {
139 *o_read_only = true;
140 }
141
142 return EOK;
143}
144
145int ext4_filesystem_get_block_group_ref(ext4_filesystem_t *fs, uint32_t bgid,
146 ext4_block_group_ref_t **ref)
147{
148 int rc;
149
150 ext4_block_group_ref_t *newref = malloc(sizeof(ext4_block_group_ref_t));
151 if (newref == NULL) {
152 return ENOMEM;
153 }
154
155 uint32_t descriptors_per_block = ext4_superblock_get_block_size(fs->superblock)
156 / ext4_superblock_get_desc_size(fs->superblock);
157
158 /* Block group descriptor table starts at the next block after superblock */
159 aoff64_t block_id = ext4_superblock_get_first_data_block(fs->superblock) + 1;
160
161 /* Find the block containing the descriptor we are looking for */
162 block_id += bgid / descriptors_per_block;
163 uint32_t offset = (bgid % descriptors_per_block) * ext4_superblock_get_desc_size(fs->superblock);
164
165 rc = block_get(&newref->block, fs->device, block_id, 0);
166 if (rc != EOK) {
167 free(newref);
168 return rc;
169 }
170
171 newref->block_group = newref->block->data + offset;
172 newref->dirty = false;
173
174 *ref = newref;
175
176 return EOK;
177}
178
179int ext4_filesystem_put_block_group_ref(ext4_block_group_ref_t *ref)
180{
181 int rc;
182
183 if (ref->dirty) {
184 ref->block->dirty = true;
185 }
186
187 rc = block_put(ref->block);
188 free(ref);
189
190 return rc;
191}
192
193int ext4_filesystem_get_inode_ref(ext4_filesystem_t *fs, uint32_t index,
194 ext4_inode_ref_t **ref)
195{
196 int rc;
197
198 ext4_inode_ref_t *newref = malloc(sizeof(ext4_inode_ref_t));
199 if (newref == NULL) {
200 return ENOMEM;
201 }
202
203 uint32_t inodes_per_group =
204 ext4_superblock_get_inodes_per_group(fs->superblock);
205
206 /* inode numbers are 1-based, but it is simpler to work with 0-based
207 * when computing indices
208 */
209 index -= 1;
210 uint32_t block_group = index / inodes_per_group;
211 uint32_t offset_in_group = index % inodes_per_group;
212
213 ext4_block_group_ref_t *bg_ref;
214 rc = ext4_filesystem_get_block_group_ref(fs, block_group, &bg_ref);
215 if (rc != EOK) {
216 free(newref);
217 return rc;
218 }
219
220 uint32_t inode_table_start = ext4_block_group_get_inode_table_first_block(
221 bg_ref->block_group, fs->superblock);
222
223 rc = ext4_filesystem_put_block_group_ref(bg_ref);
224 if (rc != EOK) {
225 free(newref);
226 return rc;
227 }
228
229 uint16_t inode_size = ext4_superblock_get_inode_size(fs->superblock);
230 uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
231 uint32_t byte_offset_in_group = offset_in_group * inode_size;
232
233 aoff64_t block_id = inode_table_start + (byte_offset_in_group / block_size);
234 rc = block_get(&newref->block, fs->device, block_id, 0);
235 if (rc != EOK) {
236 free(newref);
237 return rc;
238 }
239
240 uint32_t offset_in_block = byte_offset_in_group % block_size;
241 newref->inode = newref->block->data + offset_in_block;
242 /* we decremented index above, but need to store the original value
243 * in the reference
244 */
245 newref->index = index+1;
246 newref->dirty = false;
247
248 *ref = newref;
249
250 return EOK;
251}
252
253
254int ext4_filesystem_put_inode_ref(ext4_inode_ref_t *ref)
255{
256 int rc;
257
258 if (ref->dirty) {
259 ref->block->dirty = true;
260 }
261
262 rc = block_put(ref->block);
263 free(ref);
264
265 return rc;
266}
267
268int ext4_filesystem_alloc_inode(ext4_filesystem_t *fs,
269 ext4_inode_ref_t **inode_ref, int flags)
270{
271 int rc;
272
273 bool is_dir = false;
274 if (flags & L_DIRECTORY) {
275 is_dir = true;
276 }
277
278 // allocate inode
279 uint32_t index;
280 rc = ext4_ialloc_alloc_inode(fs, &index, is_dir);
281 if (rc != EOK) {
282 return rc;
283 }
284
285 // TODO extents, dir_index etc...
286 rc = ext4_filesystem_get_inode_ref(fs, index, inode_ref);
287 if (rc != EOK) {
288 ext4_ialloc_free_inode(fs, index, is_dir);
289 return rc;
290 }
291
292 // init inode
293 ext4_inode_t *inode = (*inode_ref)->inode;
294
295 if (is_dir) {
296 ext4_inode_set_mode(fs->superblock, inode, EXT4_INODE_MODE_DIRECTORY);
297 ext4_inode_set_links_count(inode, 1); // '.' entry
298 } else {
299 ext4_inode_set_mode(fs->superblock, inode, EXT4_INODE_MODE_FILE);
300 ext4_inode_set_links_count(inode, 0);
301 }
302
303 ext4_inode_set_uid(inode, 0);
304 ext4_inode_set_gid(inode, 0);
305 ext4_inode_set_size(inode, 0);
306 ext4_inode_set_access_time(inode, 0);
307 ext4_inode_set_change_inode_time(inode, 0);
308 ext4_inode_set_modification_time(inode, 0);
309 ext4_inode_set_deletion_time(inode, 0);
310 ext4_inode_set_blocks_count(fs->superblock, inode, 0);
311 ext4_inode_set_flags(inode, 0);
312 ext4_inode_set_generation(inode, 0);
313
314 for (uint32_t i = 0; i < EXT4_INODE_BLOCKS; i++) {
315 inode->blocks[i] = 0;
316 }
317
318 (*inode_ref)->dirty = true;
319
320 return EOK;
321}
322
323int ext4_filesystem_free_inode(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref)
324{
325 int rc;
326
327 // release all indirect blocks
328
329 // 1) Single indirect
330 uint32_t fblock = ext4_inode_get_indirect_block(inode_ref->inode, 0);
331 if (fblock != 0) {
332 rc = ext4_balloc_free_block(fs, inode_ref, fblock);
333 if (rc != EOK) {
334 // TODO error
335 }
336
337 ext4_inode_set_indirect_block(inode_ref->inode, 0, 0);
338 }
339
340 block_t *block;
341 uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
342 uint32_t count = block_size / sizeof(uint32_t);
343
344 // 2) Double indirect
345 fblock = ext4_inode_get_indirect_block(inode_ref->inode, 1);
346 if (fblock != 0) {
347 rc = block_get(&block, fs->device, fblock, BLOCK_FLAGS_NONE);
348 if (rc != EOK) {
349 // TODO error
350 }
351
352 uint32_t ind_block;
353 for (uint32_t offset = 0; offset < count; ++offset) {
354 ind_block = uint32_t_le2host(((uint32_t*)block->data)[offset]);
355
356 if (ind_block != 0) {
357 rc = ext4_balloc_free_block(fs, inode_ref, ind_block);
358 if (rc != EOK) {
359 // TODO error
360 }
361 }
362 }
363
364 block_put(block);
365 rc = ext4_balloc_free_block(fs, inode_ref, fblock);
366 if (rc != EOK) {
367 // TODO error
368 }
369
370 ext4_inode_set_indirect_block(inode_ref->inode, 1, 0);
371 }
372
373
374 // 3) Tripple indirect
375 block_t *subblock;
376 fblock = ext4_inode_get_indirect_block(inode_ref->inode, 2);
377 if (fblock != 0) {
378 rc = block_get(&block, fs->device, fblock, BLOCK_FLAGS_NONE);
379 if (rc != EOK) {
380 // TODO error
381 }
382
383 uint32_t ind_block;
384 for (uint32_t offset = 0; offset < count; ++offset) {
385 ind_block = uint32_t_le2host(((uint32_t*)block->data)[offset]);
386
387 if (ind_block != 0) {
388 rc = block_get(&subblock, fs->device, ind_block, BLOCK_FLAGS_NONE);
389 if (rc != EOK) {
390 // TODO error
391 }
392
393 uint32_t ind_subblock;
394 for (uint32_t suboffset = 0; suboffset < count; ++suboffset) {
395 ind_subblock = uint32_t_le2host(((uint32_t*)subblock->data)[suboffset]);
396
397 if (ind_subblock != 0) {
398 rc = ext4_balloc_free_block(fs, inode_ref, ind_subblock);
399 if (rc != EOK) {
400 // TODO error
401 }
402 }
403
404 }
405 block_put(subblock);
406
407 }
408
409 rc = ext4_balloc_free_block(fs, inode_ref, ind_block);
410 if (rc != EOK) {
411 // TODO error
412 }
413
414
415 }
416
417 block_put(block);
418 rc = ext4_balloc_free_block(fs, inode_ref, fblock);
419 if (rc != EOK) {
420 // TODO error
421 }
422
423 ext4_inode_set_indirect_block(inode_ref->inode, 2, 0);
424 }
425
426 inode_ref->dirty = true;
427
428 // Free inode
429 if (ext4_inode_is_type(fs->superblock, inode_ref->inode,
430 EXT4_INODE_MODE_DIRECTORY)) {
431 rc = ext4_ialloc_free_inode(fs, inode_ref->index, true);
432 } else {
433 rc = ext4_ialloc_free_inode(fs, inode_ref->index, false);
434 }
435 if (rc != EOK) {
436 return rc;
437 }
438
439 return EOK;
440}
441
442int ext4_filesystem_truncate_inode(ext4_filesystem_t *fs,
443 ext4_inode_ref_t *inode_ref, aoff64_t new_size)
444{
445 if (! ext4_inode_can_truncate(fs->superblock, inode_ref->inode)) {
446 // Unable to truncate
447 return EINVAL;
448 }
449
450 aoff64_t old_size = ext4_inode_get_size(fs->superblock, inode_ref->inode);
451 if (old_size == new_size) {
452 // Nothing to do
453 return EOK;
454 }
455
456 if (old_size < new_size) {
457 // Currently not supported to expand the file
458 // TODO
459 EXT4FS_DBG("trying to expand the file");
460 return EINVAL;
461 }
462
463 aoff64_t size_diff = old_size - new_size;
464 uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
465 uint32_t blocks_count = size_diff / block_size;
466 if (size_diff % block_size != 0) {
467 blocks_count++;
468 }
469
470 uint32_t total_blocks = old_size / block_size;
471 if (old_size % block_size != 0) {
472 total_blocks++;
473 }
474
475 // starting from 1 because of logical blocks are numbered from 0
476 for (uint32_t i = 1; i <= blocks_count; ++i) {
477 // TODO check retval
478 ext4_filesystem_release_inode_block(fs, inode_ref, total_blocks - i);
479 }
480
481 ext4_inode_set_size(inode_ref->inode, new_size);
482
483 inode_ref->dirty = true;
484
485 return EOK;
486}
487
488int ext4_filesystem_get_inode_data_block_index(ext4_filesystem_t *fs, ext4_inode_t* inode,
489 aoff64_t iblock, uint32_t* fblock)
490{
491 int rc;
492
493
494 uint32_t current_block;
495
496 /* Handle inode using extents */
497 if (ext4_superblock_has_feature_compatible(fs->superblock, EXT4_FEATURE_INCOMPAT_EXTENTS) &&
498 ext4_inode_has_flag(inode, EXT4_INODE_FLAG_EXTENTS)) {
499 current_block = ext4_inode_get_extent_block(inode, iblock, fs->device);
500 *fblock = current_block;
501 return EOK;
502
503 }
504
505 /* Handle simple case when we are dealing with direct reference */
506 if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
507 current_block = ext4_inode_get_direct_block(inode, (uint32_t)iblock);
508 *fblock = current_block;
509 return EOK;
510 }
511
512 /* Determine the indirection level needed to get the desired block */
513 int level = -1;
514 for (int i = 1; i < 4; i++) {
515 if (iblock < fs->inode_block_limits[i]) {
516 level = i;
517 break;
518 }
519 }
520
521 if (level == -1) {
522 return EIO;
523 }
524
525 /* Compute offsets for the topmost level */
526 aoff64_t block_offset_in_level = iblock - fs->inode_block_limits[level-1];
527 current_block = ext4_inode_get_indirect_block(inode, level-1);
528 uint32_t offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
529
530 if (current_block == 0) {
531 *fblock = 0;
532 return EOK;
533 }
534
535 block_t *block;
536
537 /* Navigate through other levels, until we find the block number
538 * or find null reference meaning we are dealing with sparse file
539 */
540 while (level > 0) {
541 rc = block_get(&block, fs->device, current_block, 0);
542 if (rc != EOK) {
543 return rc;
544 }
545
546 current_block = uint32_t_le2host(((uint32_t*)block->data)[offset_in_block]);
547
548 rc = block_put(block);
549 if (rc != EOK) {
550 return rc;
551 }
552
553 if (current_block == 0) {
554 /* This is a sparse file */
555 *fblock = 0;
556 return EOK;
557 }
558
559 level -= 1;
560
561 /* If we are on the last level, break here as
562 * there is no next level to visit
563 */
564 if (level == 0) {
565 break;
566 }
567
568 /* Visit the next level */
569 block_offset_in_level %= fs->inode_blocks_per_level[level];
570 offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
571 }
572
573 *fblock = current_block;
574
575 return EOK;
576}
577
578
579int ext4_filesystem_set_inode_data_block_index(ext4_filesystem_t *fs,
580 ext4_inode_ref_t *inode_ref, aoff64_t iblock, uint32_t fblock)
581{
582 int rc;
583
584
585 /* Handle inode using extents */
586 if (ext4_superblock_has_feature_compatible(fs->superblock, EXT4_FEATURE_INCOMPAT_EXTENTS) &&
587 ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS)) {
588 // TODO
589 return ENOTSUP;
590 }
591
592 /* Handle simple case when we are dealing with direct reference */
593 if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
594 ext4_inode_set_direct_block(inode_ref->inode, (uint32_t)iblock, fblock);
595 inode_ref->dirty = true;
596 return EOK;
597 }
598
599 /* Determine the indirection level needed to get the desired block */
600 int level = -1;
601 for (int i = 1; i < 4; i++) {
602 if (iblock < fs->inode_block_limits[i]) {
603 level = i;
604 break;
605 }
606 }
607
608 if (level == -1) {
609 return EIO;
610 }
611
612
613
614 uint32_t block_size = ext4_superblock_get_block_size(fs->superblock);
615
616 /* Compute offsets for the topmost level */
617 aoff64_t block_offset_in_level = iblock - fs->inode_block_limits[level-1];
618 uint32_t current_block = ext4_inode_get_indirect_block(inode_ref->inode, level-1);
619 uint32_t offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
620
621 uint32_t new_block_addr;
622 block_t *block, *new_block;
623
624 if (current_block == 0) {
625 rc = ext4_balloc_alloc_block(fs, inode_ref, &new_block_addr);
626 if (rc != EOK) {
627 // TODO error
628 EXT4FS_DBG("error in allocation");
629 }
630
631 ext4_inode_set_indirect_block(inode_ref->inode, level - 1, new_block_addr);
632
633 inode_ref->dirty = true;
634
635 rc = block_get(&new_block, fs->device, new_block_addr, BLOCK_FLAGS_NOREAD);
636 if (rc != EOK) {
637 EXT4FS_DBG("block load error");
638 // TODO error
639 }
640
641 memset(new_block->data, 0, block_size);
642 new_block->dirty = true;
643
644 rc = block_put(new_block);
645 if (rc != EOK) {
646 EXT4FS_DBG("block put error");
647 }
648
649// EXT4FS_DBG("allocated indirect block for level \%u, during setting iblock \%u", level, (uint32_t)iblock);
650
651 current_block = new_block_addr;
652 }
653
654 /* Navigate through other levels, until we find the block number
655 * or find null reference meaning we are dealing with sparse file
656 */
657 while (level > 0) {
658
659 rc = block_get(&block, fs->device, current_block, 0);
660 if (rc != EOK) {
661 return rc;
662 }
663
664 current_block = uint32_t_le2host(((uint32_t*)block->data)[offset_in_block]);
665
666 if ((level > 1) && (current_block == 0)) {
667 rc = ext4_balloc_alloc_block(fs, inode_ref, &new_block_addr);
668 if (rc != EOK) {
669 // TODO error
670 EXT4FS_DBG("allocation error");
671 }
672
673 rc = block_get(&new_block, fs->device, new_block_addr, BLOCK_FLAGS_NOREAD);
674 if (rc != EOK) {
675 // TODO error
676
677 EXT4FS_DBG("BBB: error block loading");
678
679 }
680 memset(new_block->data, 0, block_size);
681 new_block->dirty = true;
682
683 rc = block_put(new_block);
684 if (rc != EOK) {
685 EXT4FS_DBG("BBB: error indirect block saving");
686 }
687
688 ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(new_block_addr);
689 block->dirty = true;
690 current_block = new_block_addr;
691 }
692
693 if (level == 1) {
694 ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(fblock);
695 block->dirty = true;
696 }
697
698 rc = block_put(block);
699 if (rc != EOK) {
700 return rc;
701 }
702
703 level -= 1;
704
705 /* If we are on the last level, break here as
706 * there is no next level to visit
707 */
708 if (level == 0) {
709 break;
710 }
711
712 /* Visit the next level */
713 block_offset_in_level %= fs->inode_blocks_per_level[level];
714 offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
715 }
716
717 return EOK;
718}
719
720int ext4_filesystem_release_inode_block(ext4_filesystem_t *fs,
721 ext4_inode_ref_t *inode_ref, uint32_t iblock)
722{
723 int rc;
724
725
726 /* TODO handle extents */
727
728
729 uint32_t fblock;
730 ext4_inode_t *inode = inode_ref->inode;
731
732 /* Handle simple case when we are dealing with direct reference */
733 if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
734 fblock = ext4_inode_get_direct_block(inode, iblock);
735 // Sparse file
736 if (fblock == 0) {
737 return EOK;
738 }
739
740 ext4_inode_set_direct_block(inode, iblock, 0);
741 return ext4_balloc_free_block(fs, inode_ref, fblock);
742 }
743
744
745 /* Determine the indirection level needed to get the desired block */
746 int level = -1;
747 for (int i = 1; i < 4; i++) {
748 if (iblock < fs->inode_block_limits[i]) {
749 level = i;
750 break;
751 }
752 }
753
754 if (level == -1) {
755 return EIO;
756 }
757
758 /* Compute offsets for the topmost level */
759 aoff64_t block_offset_in_level = iblock - fs->inode_block_limits[level-1];
760 uint32_t current_block = ext4_inode_get_indirect_block(inode, level-1);
761 uint32_t offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
762
763 /* Navigate through other levels, until we find the block number
764 * or find null reference meaning we are dealing with sparse file
765 */
766 block_t *block;
767 while (level > 0) {
768 rc = block_get(&block, fs->device, current_block, 0);
769 if (rc != EOK) {
770 return rc;
771 }
772
773 current_block = uint32_t_le2host(((uint32_t*)block->data)[offset_in_block]);
774
775 // Set zero
776 if (level == 1) {
777 ((uint32_t*)block->data)[offset_in_block] = host2uint32_t_le(0);
778 block->dirty = true;
779 }
780
781 rc = block_put(block);
782 if (rc != EOK) {
783 return rc;
784 }
785
786 level -= 1;
787
788 /* If we are on the last level, break here as
789 * there is no next level to visit
790 */
791 if (level == 0) {
792 break;
793 }
794
795 /* Visit the next level */
796 block_offset_in_level %= fs->inode_blocks_per_level[level];
797 offset_in_block = block_offset_in_level / fs->inode_blocks_per_level[level-1];
798 }
799
800 fblock = current_block;
801
802 if (fblock == 0) {
803 return EOK;
804 }
805
806 return ext4_balloc_free_block(fs, inode_ref, fblock);
807
808}
809
810int ext4_filesystem_add_orphan(ext4_filesystem_t *fs,
811 ext4_inode_ref_t *inode_ref)
812{
813 uint32_t next_orphan = ext4_superblock_get_last_orphan(fs->superblock);
814 ext4_inode_set_deletion_time(inode_ref->inode, next_orphan);
815 ext4_superblock_set_last_orphan(fs->superblock, inode_ref->index);
816 inode_ref->dirty = true;
817
818 return EOK;
819}
820
821int ext4_filesystem_delete_orphan(ext4_filesystem_t *fs,
822 ext4_inode_ref_t *inode_ref)
823{
824 int rc;
825
826 uint32_t last_orphan = ext4_superblock_get_last_orphan(fs->superblock);
827 assert(last_orphan > 0);
828
829 uint32_t next_orphan = ext4_inode_get_deletion_time(inode_ref->inode);
830
831 if (last_orphan == inode_ref->index) {
832 ext4_superblock_set_last_orphan(fs->superblock, next_orphan);
833 ext4_inode_set_deletion_time(inode_ref->inode, 0);
834 inode_ref->dirty = true;
835 return EOK;
836 }
837
838 ext4_inode_ref_t *current;
839 rc = ext4_filesystem_get_inode_ref(fs, last_orphan, &current);
840 if (rc != EOK) {
841 return rc;
842 }
843 next_orphan = ext4_inode_get_deletion_time(current->inode);
844
845 bool found;
846
847 while (next_orphan != 0) {
848 if (next_orphan == inode_ref->index) {
849 next_orphan = ext4_inode_get_deletion_time(inode_ref->inode);
850 ext4_inode_set_deletion_time(current->inode, next_orphan);
851 current->dirty = true;
852 found = true;
853 break;
854 }
855
856 ext4_filesystem_put_inode_ref(current);
857
858 rc = ext4_filesystem_get_inode_ref(fs, next_orphan, &current);
859 if (rc != EOK) {
860 return rc;
861 }
862 next_orphan = ext4_inode_get_deletion_time(current->inode);
863
864 }
865
866 ext4_inode_set_deletion_time(inode_ref->inode, 0);
867
868 rc = ext4_filesystem_put_inode_ref(current);
869 if (rc != EOK) {
870 return rc;
871 }
872
873 if (!found) {
874 return ENOENT;
875 }
876
877 return EOK;
878}
879
880/**
881 * @}
882 */
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