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 */
ext2fs_flush_icache(ext2_filsys fs)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
create_icache(ext2_filsys fs)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
ext2fs_open_inode_scan(ext2_filsys fs,int buffer_blocks,ext2_inode_scan * ret_scan)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
ext2fs_close_inode_scan(ext2_inode_scan scan)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
ext2fs_set_inode_callback(ext2_inode_scan scan,errcode_t (* done_group)(ext2_filsys fs,ext2_inode_scan scan,dgrp_t group,void * priv_data),void * done_group_data)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
ext2fs_inode_scan_flags(ext2_inode_scan scan,int set_flags,int clear_flags)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 */
get_next_blockgroup(ext2_inode_scan scan)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
ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan,int group)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 */
check_for_inode_bad_blocks(ext2_inode_scan scan,blk_t * num_blocks)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 */
get_next_blocks(ext2_inode_scan scan)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
ext2fs_get_next_inode_full(ext2_inode_scan scan,ext2_ino_t * ino,struct ext2_inode * inode,int bufsize)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
ext2fs_get_next_inode(ext2_inode_scan scan,ext2_ino_t * ino,struct ext2_inode * inode)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 */
ext2fs_read_inode_full(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,int bufsize)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
ext2fs_read_inode(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode)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
ext2fs_write_inode_full(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,int bufsize)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
ext2fs_write_inode(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode)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 */
ext2fs_write_new_inode(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode)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
ext2fs_get_blocks(ext2_filsys fs,ext2_ino_t ino,blk_t * blocks)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
ext2fs_check_directory(ext2_filsys fs,ext2_ino_t ino)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