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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/ext2/dir.c
4 *
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Laboratoire MASI - Institut Blaise Pascal
8 * Universite Pierre et Marie Curie (Paris VI)
9 *
10 * from
11 *
12 * linux/fs/minix/dir.c
13 *
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * ext2 directory handling functions
17 *
18 * Big-endian to little-endian byte-swapping/bitmaps by
19 * David S. Miller (davem@caip.rutgers.edu), 1995
20 *
21 * All code that works with directory layout had been switched to pagecache
22 * and moved here. AV
23 */
24
25#include "ext2.h"
26#include <linux/buffer_head.h>
27#include <linux/pagemap.h>
28#include <linux/swap.h>
29#include <linux/iversion.h>
30
31typedef struct ext2_dir_entry_2 ext2_dirent;
32
33/*
34 * Tests against MAX_REC_LEN etc were put in place for 64k block
35 * sizes; if that is not possible on this arch, we can skip
36 * those tests and speed things up.
37 */
38static inline unsigned ext2_rec_len_from_disk(__le16 dlen)
39{
40 unsigned len = le16_to_cpu(dlen);
41
42#if (PAGE_SIZE >= 65536)
43 if (len == EXT2_MAX_REC_LEN)
44 return 1 << 16;
45#endif
46 return len;
47}
48
49static inline __le16 ext2_rec_len_to_disk(unsigned len)
50{
51#if (PAGE_SIZE >= 65536)
52 if (len == (1 << 16))
53 return cpu_to_le16(EXT2_MAX_REC_LEN);
54 else
55 BUG_ON(len > (1 << 16));
56#endif
57 return cpu_to_le16(len);
58}
59
60/*
61 * ext2 uses block-sized chunks. Arguably, sector-sized ones would be
62 * more robust, but we have what we have
63 */
64static inline unsigned ext2_chunk_size(struct inode *inode)
65{
66 return inode->i_sb->s_blocksize;
67}
68
69static inline void ext2_put_page(struct page *page)
70{
71 kunmap(page);
72 put_page(page);
73}
74
75/*
76 * Return the offset into page `page_nr' of the last valid
77 * byte in that page, plus one.
78 */
79static unsigned
80ext2_last_byte(struct inode *inode, unsigned long page_nr)
81{
82 unsigned last_byte = inode->i_size;
83
84 last_byte -= page_nr << PAGE_SHIFT;
85 if (last_byte > PAGE_SIZE)
86 last_byte = PAGE_SIZE;
87 return last_byte;
88}
89
90static int ext2_commit_chunk(struct page *page, loff_t pos, unsigned len)
91{
92 struct address_space *mapping = page->mapping;
93 struct inode *dir = mapping->host;
94 int err = 0;
95
96 inode_inc_iversion(dir);
97 block_write_end(NULL, mapping, pos, len, len, page, NULL);
98
99 if (pos+len > dir->i_size) {
100 i_size_write(dir, pos+len);
101 mark_inode_dirty(dir);
102 }
103
104 if (IS_DIRSYNC(dir)) {
105 err = write_one_page(page);
106 if (!err)
107 err = sync_inode_metadata(dir, 1);
108 } else {
109 unlock_page(page);
110 }
111
112 return err;
113}
114
115static bool ext2_check_page(struct page *page, int quiet)
116{
117 struct inode *dir = page->mapping->host;
118 struct super_block *sb = dir->i_sb;
119 unsigned chunk_size = ext2_chunk_size(dir);
120 char *kaddr = page_address(page);
121 u32 max_inumber = le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count);
122 unsigned offs, rec_len;
123 unsigned limit = PAGE_SIZE;
124 ext2_dirent *p;
125 char *error;
126
127 if ((dir->i_size >> PAGE_SHIFT) == page->index) {
128 limit = dir->i_size & ~PAGE_MASK;
129 if (limit & (chunk_size - 1))
130 goto Ebadsize;
131 if (!limit)
132 goto out;
133 }
134 for (offs = 0; offs <= limit - EXT2_DIR_REC_LEN(1); offs += rec_len) {
135 p = (ext2_dirent *)(kaddr + offs);
136 rec_len = ext2_rec_len_from_disk(p->rec_len);
137
138 if (unlikely(rec_len < EXT2_DIR_REC_LEN(1)))
139 goto Eshort;
140 if (unlikely(rec_len & 3))
141 goto Ealign;
142 if (unlikely(rec_len < EXT2_DIR_REC_LEN(p->name_len)))
143 goto Enamelen;
144 if (unlikely(((offs + rec_len - 1) ^ offs) & ~(chunk_size-1)))
145 goto Espan;
146 if (unlikely(le32_to_cpu(p->inode) > max_inumber))
147 goto Einumber;
148 }
149 if (offs != limit)
150 goto Eend;
151out:
152 SetPageChecked(page);
153 return true;
154
155 /* Too bad, we had an error */
156
157Ebadsize:
158 if (!quiet)
159 ext2_error(sb, __func__,
160 "size of directory #%lu is not a multiple "
161 "of chunk size", dir->i_ino);
162 goto fail;
163Eshort:
164 error = "rec_len is smaller than minimal";
165 goto bad_entry;
166Ealign:
167 error = "unaligned directory entry";
168 goto bad_entry;
169Enamelen:
170 error = "rec_len is too small for name_len";
171 goto bad_entry;
172Espan:
173 error = "directory entry across blocks";
174 goto bad_entry;
175Einumber:
176 error = "inode out of bounds";
177bad_entry:
178 if (!quiet)
179 ext2_error(sb, __func__, "bad entry in directory #%lu: : %s - "
180 "offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
181 dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs,
182 (unsigned long) le32_to_cpu(p->inode),
183 rec_len, p->name_len);
184 goto fail;
185Eend:
186 if (!quiet) {
187 p = (ext2_dirent *)(kaddr + offs);
188 ext2_error(sb, "ext2_check_page",
189 "entry in directory #%lu spans the page boundary"
190 "offset=%lu, inode=%lu",
191 dir->i_ino, (page->index<<PAGE_SHIFT)+offs,
192 (unsigned long) le32_to_cpu(p->inode));
193 }
194fail:
195 SetPageError(page);
196 return false;
197}
198
199static struct page * ext2_get_page(struct inode *dir, unsigned long n,
200 int quiet)
201{
202 struct address_space *mapping = dir->i_mapping;
203 struct page *page = read_mapping_page(mapping, n, NULL);
204 if (!IS_ERR(page)) {
205 kmap(page);
206 if (unlikely(!PageChecked(page))) {
207 if (PageError(page) || !ext2_check_page(page, quiet))
208 goto fail;
209 }
210 }
211 return page;
212
213fail:
214 ext2_put_page(page);
215 return ERR_PTR(-EIO);
216}
217
218/*
219 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
220 *
221 * len <= EXT2_NAME_LEN and de != NULL are guaranteed by caller.
222 */
223static inline int ext2_match (int len, const char * const name,
224 struct ext2_dir_entry_2 * de)
225{
226 if (len != de->name_len)
227 return 0;
228 if (!de->inode)
229 return 0;
230 return !memcmp(name, de->name, len);
231}
232
233/*
234 * p is at least 6 bytes before the end of page
235 */
236static inline ext2_dirent *ext2_next_entry(ext2_dirent *p)
237{
238 return (ext2_dirent *)((char *)p +
239 ext2_rec_len_from_disk(p->rec_len));
240}
241
242static inline unsigned
243ext2_validate_entry(char *base, unsigned offset, unsigned mask)
244{
245 ext2_dirent *de = (ext2_dirent*)(base + offset);
246 ext2_dirent *p = (ext2_dirent*)(base + (offset&mask));
247 while ((char*)p < (char*)de) {
248 if (p->rec_len == 0)
249 break;
250 p = ext2_next_entry(p);
251 }
252 return (char *)p - base;
253}
254
255static inline void ext2_set_de_type(ext2_dirent *de, struct inode *inode)
256{
257 if (EXT2_HAS_INCOMPAT_FEATURE(inode->i_sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
258 de->file_type = fs_umode_to_ftype(inode->i_mode);
259 else
260 de->file_type = 0;
261}
262
263static int
264ext2_readdir(struct file *file, struct dir_context *ctx)
265{
266 loff_t pos = ctx->pos;
267 struct inode *inode = file_inode(file);
268 struct super_block *sb = inode->i_sb;
269 unsigned int offset = pos & ~PAGE_MASK;
270 unsigned long n = pos >> PAGE_SHIFT;
271 unsigned long npages = dir_pages(inode);
272 unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
273 bool need_revalidate = !inode_eq_iversion(inode, file->f_version);
274 bool has_filetype;
275
276 if (pos > inode->i_size - EXT2_DIR_REC_LEN(1))
277 return 0;
278
279 has_filetype =
280 EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_FILETYPE);
281
282 for ( ; n < npages; n++, offset = 0) {
283 char *kaddr, *limit;
284 ext2_dirent *de;
285 struct page *page = ext2_get_page(inode, n, 0);
286
287 if (IS_ERR(page)) {
288 ext2_error(sb, __func__,
289 "bad page in #%lu",
290 inode->i_ino);
291 ctx->pos += PAGE_SIZE - offset;
292 return PTR_ERR(page);
293 }
294 kaddr = page_address(page);
295 if (unlikely(need_revalidate)) {
296 if (offset) {
297 offset = ext2_validate_entry(kaddr, offset, chunk_mask);
298 ctx->pos = (n<<PAGE_SHIFT) + offset;
299 }
300 file->f_version = inode_query_iversion(inode);
301 need_revalidate = false;
302 }
303 de = (ext2_dirent *)(kaddr+offset);
304 limit = kaddr + ext2_last_byte(inode, n) - EXT2_DIR_REC_LEN(1);
305 for ( ;(char*)de <= limit; de = ext2_next_entry(de)) {
306 if (de->rec_len == 0) {
307 ext2_error(sb, __func__,
308 "zero-length directory entry");
309 ext2_put_page(page);
310 return -EIO;
311 }
312 if (de->inode) {
313 unsigned char d_type = DT_UNKNOWN;
314
315 if (has_filetype)
316 d_type = fs_ftype_to_dtype(de->file_type);
317
318 if (!dir_emit(ctx, de->name, de->name_len,
319 le32_to_cpu(de->inode),
320 d_type)) {
321 ext2_put_page(page);
322 return 0;
323 }
324 }
325 ctx->pos += ext2_rec_len_from_disk(de->rec_len);
326 }
327 ext2_put_page(page);
328 }
329 return 0;
330}
331
332/*
333 * ext2_find_entry()
334 *
335 * finds an entry in the specified directory with the wanted name. It
336 * returns the page in which the entry was found (as a parameter - res_page),
337 * and the entry itself. Page is returned mapped and unlocked.
338 * Entry is guaranteed to be valid.
339 */
340struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir,
341 const struct qstr *child, struct page **res_page)
342{
343 const char *name = child->name;
344 int namelen = child->len;
345 unsigned reclen = EXT2_DIR_REC_LEN(namelen);
346 unsigned long start, n;
347 unsigned long npages = dir_pages(dir);
348 struct page *page = NULL;
349 struct ext2_inode_info *ei = EXT2_I(dir);
350 ext2_dirent * de;
351 int dir_has_error = 0;
352
353 if (npages == 0)
354 goto out;
355
356 /* OFFSET_CACHE */
357 *res_page = NULL;
358
359 start = ei->i_dir_start_lookup;
360 if (start >= npages)
361 start = 0;
362 n = start;
363 do {
364 char *kaddr;
365 page = ext2_get_page(dir, n, dir_has_error);
366 if (!IS_ERR(page)) {
367 kaddr = page_address(page);
368 de = (ext2_dirent *) kaddr;
369 kaddr += ext2_last_byte(dir, n) - reclen;
370 while ((char *) de <= kaddr) {
371 if (de->rec_len == 0) {
372 ext2_error(dir->i_sb, __func__,
373 "zero-length directory entry");
374 ext2_put_page(page);
375 goto out;
376 }
377 if (ext2_match (namelen, name, de))
378 goto found;
379 de = ext2_next_entry(de);
380 }
381 ext2_put_page(page);
382 } else
383 dir_has_error = 1;
384
385 if (++n >= npages)
386 n = 0;
387 /* next page is past the blocks we've got */
388 if (unlikely(n > (dir->i_blocks >> (PAGE_SHIFT - 9)))) {
389 ext2_error(dir->i_sb, __func__,
390 "dir %lu size %lld exceeds block count %llu",
391 dir->i_ino, dir->i_size,
392 (unsigned long long)dir->i_blocks);
393 goto out;
394 }
395 } while (n != start);
396out:
397 return NULL;
398
399found:
400 *res_page = page;
401 ei->i_dir_start_lookup = n;
402 return de;
403}
404
405struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p)
406{
407 struct page *page = ext2_get_page(dir, 0, 0);
408 ext2_dirent *de = NULL;
409
410 if (!IS_ERR(page)) {
411 de = ext2_next_entry((ext2_dirent *) page_address(page));
412 *p = page;
413 }
414 return de;
415}
416
417ino_t ext2_inode_by_name(struct inode *dir, const struct qstr *child)
418{
419 ino_t res = 0;
420 struct ext2_dir_entry_2 *de;
421 struct page *page;
422
423 de = ext2_find_entry (dir, child, &page);
424 if (de) {
425 res = le32_to_cpu(de->inode);
426 ext2_put_page(page);
427 }
428 return res;
429}
430
431static int ext2_prepare_chunk(struct page *page, loff_t pos, unsigned len)
432{
433 return __block_write_begin(page, pos, len, ext2_get_block);
434}
435
436/* Releases the page */
437void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
438 struct page *page, struct inode *inode, int update_times)
439{
440 loff_t pos = page_offset(page) +
441 (char *) de - (char *) page_address(page);
442 unsigned len = ext2_rec_len_from_disk(de->rec_len);
443 int err;
444
445 lock_page(page);
446 err = ext2_prepare_chunk(page, pos, len);
447 BUG_ON(err);
448 de->inode = cpu_to_le32(inode->i_ino);
449 ext2_set_de_type(de, inode);
450 err = ext2_commit_chunk(page, pos, len);
451 ext2_put_page(page);
452 if (update_times)
453 dir->i_mtime = dir->i_ctime = current_time(dir);
454 EXT2_I(dir)->i_flags &= ~EXT2_BTREE_FL;
455 mark_inode_dirty(dir);
456}
457
458/*
459 * Parent is locked.
460 */
461int ext2_add_link (struct dentry *dentry, struct inode *inode)
462{
463 struct inode *dir = d_inode(dentry->d_parent);
464 const char *name = dentry->d_name.name;
465 int namelen = dentry->d_name.len;
466 unsigned chunk_size = ext2_chunk_size(dir);
467 unsigned reclen = EXT2_DIR_REC_LEN(namelen);
468 unsigned short rec_len, name_len;
469 struct page *page = NULL;
470 ext2_dirent * de;
471 unsigned long npages = dir_pages(dir);
472 unsigned long n;
473 char *kaddr;
474 loff_t pos;
475 int err;
476
477 /*
478 * We take care of directory expansion in the same loop.
479 * This code plays outside i_size, so it locks the page
480 * to protect that region.
481 */
482 for (n = 0; n <= npages; n++) {
483 char *dir_end;
484
485 page = ext2_get_page(dir, n, 0);
486 err = PTR_ERR(page);
487 if (IS_ERR(page))
488 goto out;
489 lock_page(page);
490 kaddr = page_address(page);
491 dir_end = kaddr + ext2_last_byte(dir, n);
492 de = (ext2_dirent *)kaddr;
493 kaddr += PAGE_SIZE - reclen;
494 while ((char *)de <= kaddr) {
495 if ((char *)de == dir_end) {
496 /* We hit i_size */
497 name_len = 0;
498 rec_len = chunk_size;
499 de->rec_len = ext2_rec_len_to_disk(chunk_size);
500 de->inode = 0;
501 goto got_it;
502 }
503 if (de->rec_len == 0) {
504 ext2_error(dir->i_sb, __func__,
505 "zero-length directory entry");
506 err = -EIO;
507 goto out_unlock;
508 }
509 err = -EEXIST;
510 if (ext2_match (namelen, name, de))
511 goto out_unlock;
512 name_len = EXT2_DIR_REC_LEN(de->name_len);
513 rec_len = ext2_rec_len_from_disk(de->rec_len);
514 if (!de->inode && rec_len >= reclen)
515 goto got_it;
516 if (rec_len >= name_len + reclen)
517 goto got_it;
518 de = (ext2_dirent *) ((char *) de + rec_len);
519 }
520 unlock_page(page);
521 ext2_put_page(page);
522 }
523 BUG();
524 return -EINVAL;
525
526got_it:
527 pos = page_offset(page) +
528 (char*)de - (char*)page_address(page);
529 err = ext2_prepare_chunk(page, pos, rec_len);
530 if (err)
531 goto out_unlock;
532 if (de->inode) {
533 ext2_dirent *de1 = (ext2_dirent *) ((char *) de + name_len);
534 de1->rec_len = ext2_rec_len_to_disk(rec_len - name_len);
535 de->rec_len = ext2_rec_len_to_disk(name_len);
536 de = de1;
537 }
538 de->name_len = namelen;
539 memcpy(de->name, name, namelen);
540 de->inode = cpu_to_le32(inode->i_ino);
541 ext2_set_de_type (de, inode);
542 err = ext2_commit_chunk(page, pos, rec_len);
543 dir->i_mtime = dir->i_ctime = current_time(dir);
544 EXT2_I(dir)->i_flags &= ~EXT2_BTREE_FL;
545 mark_inode_dirty(dir);
546 /* OFFSET_CACHE */
547out_put:
548 ext2_put_page(page);
549out:
550 return err;
551out_unlock:
552 unlock_page(page);
553 goto out_put;
554}
555
556/*
557 * ext2_delete_entry deletes a directory entry by merging it with the
558 * previous entry. Page is up-to-date. Releases the page.
559 */
560int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
561{
562 struct inode *inode = page->mapping->host;
563 char *kaddr = page_address(page);
564 unsigned from = ((char*)dir - kaddr) & ~(ext2_chunk_size(inode)-1);
565 unsigned to = ((char *)dir - kaddr) +
566 ext2_rec_len_from_disk(dir->rec_len);
567 loff_t pos;
568 ext2_dirent * pde = NULL;
569 ext2_dirent * de = (ext2_dirent *) (kaddr + from);
570 int err;
571
572 while ((char*)de < (char*)dir) {
573 if (de->rec_len == 0) {
574 ext2_error(inode->i_sb, __func__,
575 "zero-length directory entry");
576 err = -EIO;
577 goto out;
578 }
579 pde = de;
580 de = ext2_next_entry(de);
581 }
582 if (pde)
583 from = (char*)pde - (char*)page_address(page);
584 pos = page_offset(page) + from;
585 lock_page(page);
586 err = ext2_prepare_chunk(page, pos, to - from);
587 BUG_ON(err);
588 if (pde)
589 pde->rec_len = ext2_rec_len_to_disk(to - from);
590 dir->inode = 0;
591 err = ext2_commit_chunk(page, pos, to - from);
592 inode->i_ctime = inode->i_mtime = current_time(inode);
593 EXT2_I(inode)->i_flags &= ~EXT2_BTREE_FL;
594 mark_inode_dirty(inode);
595out:
596 ext2_put_page(page);
597 return err;
598}
599
600/*
601 * Set the first fragment of directory.
602 */
603int ext2_make_empty(struct inode *inode, struct inode *parent)
604{
605 struct page *page = grab_cache_page(inode->i_mapping, 0);
606 unsigned chunk_size = ext2_chunk_size(inode);
607 struct ext2_dir_entry_2 * de;
608 int err;
609 void *kaddr;
610
611 if (!page)
612 return -ENOMEM;
613
614 err = ext2_prepare_chunk(page, 0, chunk_size);
615 if (err) {
616 unlock_page(page);
617 goto fail;
618 }
619 kaddr = kmap_atomic(page);
620 memset(kaddr, 0, chunk_size);
621 de = (struct ext2_dir_entry_2 *)kaddr;
622 de->name_len = 1;
623 de->rec_len = ext2_rec_len_to_disk(EXT2_DIR_REC_LEN(1));
624 memcpy (de->name, ".\0\0", 4);
625 de->inode = cpu_to_le32(inode->i_ino);
626 ext2_set_de_type (de, inode);
627
628 de = (struct ext2_dir_entry_2 *)(kaddr + EXT2_DIR_REC_LEN(1));
629 de->name_len = 2;
630 de->rec_len = ext2_rec_len_to_disk(chunk_size - EXT2_DIR_REC_LEN(1));
631 de->inode = cpu_to_le32(parent->i_ino);
632 memcpy (de->name, "..\0", 4);
633 ext2_set_de_type (de, inode);
634 kunmap_atomic(kaddr);
635 err = ext2_commit_chunk(page, 0, chunk_size);
636fail:
637 put_page(page);
638 return err;
639}
640
641/*
642 * routine to check that the specified directory is empty (for rmdir)
643 */
644int ext2_empty_dir (struct inode * inode)
645{
646 struct page *page = NULL;
647 unsigned long i, npages = dir_pages(inode);
648 int dir_has_error = 0;
649
650 for (i = 0; i < npages; i++) {
651 char *kaddr;
652 ext2_dirent * de;
653 page = ext2_get_page(inode, i, dir_has_error);
654
655 if (IS_ERR(page)) {
656 dir_has_error = 1;
657 continue;
658 }
659
660 kaddr = page_address(page);
661 de = (ext2_dirent *)kaddr;
662 kaddr += ext2_last_byte(inode, i) - EXT2_DIR_REC_LEN(1);
663
664 while ((char *)de <= kaddr) {
665 if (de->rec_len == 0) {
666 ext2_error(inode->i_sb, __func__,
667 "zero-length directory entry");
668 printk("kaddr=%p, de=%p\n", kaddr, de);
669 goto not_empty;
670 }
671 if (de->inode != 0) {
672 /* check for . and .. */
673 if (de->name[0] != '.')
674 goto not_empty;
675 if (de->name_len > 2)
676 goto not_empty;
677 if (de->name_len < 2) {
678 if (de->inode !=
679 cpu_to_le32(inode->i_ino))
680 goto not_empty;
681 } else if (de->name[1] != '.')
682 goto not_empty;
683 }
684 de = ext2_next_entry(de);
685 }
686 ext2_put_page(page);
687 }
688 return 1;
689
690not_empty:
691 ext2_put_page(page);
692 return 0;
693}
694
695const struct file_operations ext2_dir_operations = {
696 .llseek = generic_file_llseek,
697 .read = generic_read_dir,
698 .iterate_shared = ext2_readdir,
699 .unlocked_ioctl = ext2_ioctl,
700#ifdef CONFIG_COMPAT
701 .compat_ioctl = ext2_compat_ioctl,
702#endif
703 .fsync = ext2_fsync,
704};
1/*
2 * linux/fs/ext2/dir.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/dir.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * ext2 directory handling functions
16 *
17 * Big-endian to little-endian byte-swapping/bitmaps by
18 * David S. Miller (davem@caip.rutgers.edu), 1995
19 *
20 * All code that works with directory layout had been switched to pagecache
21 * and moved here. AV
22 */
23
24#include "ext2.h"
25#include <linux/buffer_head.h>
26#include <linux/pagemap.h>
27#include <linux/swap.h>
28
29typedef struct ext2_dir_entry_2 ext2_dirent;
30
31/*
32 * Tests against MAX_REC_LEN etc were put in place for 64k block
33 * sizes; if that is not possible on this arch, we can skip
34 * those tests and speed things up.
35 */
36static inline unsigned ext2_rec_len_from_disk(__le16 dlen)
37{
38 unsigned len = le16_to_cpu(dlen);
39
40#if (PAGE_CACHE_SIZE >= 65536)
41 if (len == EXT2_MAX_REC_LEN)
42 return 1 << 16;
43#endif
44 return len;
45}
46
47static inline __le16 ext2_rec_len_to_disk(unsigned len)
48{
49#if (PAGE_CACHE_SIZE >= 65536)
50 if (len == (1 << 16))
51 return cpu_to_le16(EXT2_MAX_REC_LEN);
52 else
53 BUG_ON(len > (1 << 16));
54#endif
55 return cpu_to_le16(len);
56}
57
58/*
59 * ext2 uses block-sized chunks. Arguably, sector-sized ones would be
60 * more robust, but we have what we have
61 */
62static inline unsigned ext2_chunk_size(struct inode *inode)
63{
64 return inode->i_sb->s_blocksize;
65}
66
67static inline void ext2_put_page(struct page *page)
68{
69 kunmap(page);
70 page_cache_release(page);
71}
72
73static inline unsigned long dir_pages(struct inode *inode)
74{
75 return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
76}
77
78/*
79 * Return the offset into page `page_nr' of the last valid
80 * byte in that page, plus one.
81 */
82static unsigned
83ext2_last_byte(struct inode *inode, unsigned long page_nr)
84{
85 unsigned last_byte = inode->i_size;
86
87 last_byte -= page_nr << PAGE_CACHE_SHIFT;
88 if (last_byte > PAGE_CACHE_SIZE)
89 last_byte = PAGE_CACHE_SIZE;
90 return last_byte;
91}
92
93static int ext2_commit_chunk(struct page *page, loff_t pos, unsigned len)
94{
95 struct address_space *mapping = page->mapping;
96 struct inode *dir = mapping->host;
97 int err = 0;
98
99 dir->i_version++;
100 block_write_end(NULL, mapping, pos, len, len, page, NULL);
101
102 if (pos+len > dir->i_size) {
103 i_size_write(dir, pos+len);
104 mark_inode_dirty(dir);
105 }
106
107 if (IS_DIRSYNC(dir)) {
108 err = write_one_page(page, 1);
109 if (!err)
110 err = sync_inode_metadata(dir, 1);
111 } else {
112 unlock_page(page);
113 }
114
115 return err;
116}
117
118static void ext2_check_page(struct page *page, int quiet)
119{
120 struct inode *dir = page->mapping->host;
121 struct super_block *sb = dir->i_sb;
122 unsigned chunk_size = ext2_chunk_size(dir);
123 char *kaddr = page_address(page);
124 u32 max_inumber = le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count);
125 unsigned offs, rec_len;
126 unsigned limit = PAGE_CACHE_SIZE;
127 ext2_dirent *p;
128 char *error;
129
130 if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
131 limit = dir->i_size & ~PAGE_CACHE_MASK;
132 if (limit & (chunk_size - 1))
133 goto Ebadsize;
134 if (!limit)
135 goto out;
136 }
137 for (offs = 0; offs <= limit - EXT2_DIR_REC_LEN(1); offs += rec_len) {
138 p = (ext2_dirent *)(kaddr + offs);
139 rec_len = ext2_rec_len_from_disk(p->rec_len);
140
141 if (unlikely(rec_len < EXT2_DIR_REC_LEN(1)))
142 goto Eshort;
143 if (unlikely(rec_len & 3))
144 goto Ealign;
145 if (unlikely(rec_len < EXT2_DIR_REC_LEN(p->name_len)))
146 goto Enamelen;
147 if (unlikely(((offs + rec_len - 1) ^ offs) & ~(chunk_size-1)))
148 goto Espan;
149 if (unlikely(le32_to_cpu(p->inode) > max_inumber))
150 goto Einumber;
151 }
152 if (offs != limit)
153 goto Eend;
154out:
155 SetPageChecked(page);
156 return;
157
158 /* Too bad, we had an error */
159
160Ebadsize:
161 if (!quiet)
162 ext2_error(sb, __func__,
163 "size of directory #%lu is not a multiple "
164 "of chunk size", dir->i_ino);
165 goto fail;
166Eshort:
167 error = "rec_len is smaller than minimal";
168 goto bad_entry;
169Ealign:
170 error = "unaligned directory entry";
171 goto bad_entry;
172Enamelen:
173 error = "rec_len is too small for name_len";
174 goto bad_entry;
175Espan:
176 error = "directory entry across blocks";
177 goto bad_entry;
178Einumber:
179 error = "inode out of bounds";
180bad_entry:
181 if (!quiet)
182 ext2_error(sb, __func__, "bad entry in directory #%lu: : %s - "
183 "offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
184 dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
185 (unsigned long) le32_to_cpu(p->inode),
186 rec_len, p->name_len);
187 goto fail;
188Eend:
189 if (!quiet) {
190 p = (ext2_dirent *)(kaddr + offs);
191 ext2_error(sb, "ext2_check_page",
192 "entry in directory #%lu spans the page boundary"
193 "offset=%lu, inode=%lu",
194 dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
195 (unsigned long) le32_to_cpu(p->inode));
196 }
197fail:
198 SetPageChecked(page);
199 SetPageError(page);
200}
201
202static struct page * ext2_get_page(struct inode *dir, unsigned long n,
203 int quiet)
204{
205 struct address_space *mapping = dir->i_mapping;
206 struct page *page = read_mapping_page(mapping, n, NULL);
207 if (!IS_ERR(page)) {
208 kmap(page);
209 if (!PageChecked(page))
210 ext2_check_page(page, quiet);
211 if (PageError(page))
212 goto fail;
213 }
214 return page;
215
216fail:
217 ext2_put_page(page);
218 return ERR_PTR(-EIO);
219}
220
221/*
222 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
223 *
224 * len <= EXT2_NAME_LEN and de != NULL are guaranteed by caller.
225 */
226static inline int ext2_match (int len, const char * const name,
227 struct ext2_dir_entry_2 * de)
228{
229 if (len != de->name_len)
230 return 0;
231 if (!de->inode)
232 return 0;
233 return !memcmp(name, de->name, len);
234}
235
236/*
237 * p is at least 6 bytes before the end of page
238 */
239static inline ext2_dirent *ext2_next_entry(ext2_dirent *p)
240{
241 return (ext2_dirent *)((char *)p +
242 ext2_rec_len_from_disk(p->rec_len));
243}
244
245static inline unsigned
246ext2_validate_entry(char *base, unsigned offset, unsigned mask)
247{
248 ext2_dirent *de = (ext2_dirent*)(base + offset);
249 ext2_dirent *p = (ext2_dirent*)(base + (offset&mask));
250 while ((char*)p < (char*)de) {
251 if (p->rec_len == 0)
252 break;
253 p = ext2_next_entry(p);
254 }
255 return (char *)p - base;
256}
257
258static unsigned char ext2_filetype_table[EXT2_FT_MAX] = {
259 [EXT2_FT_UNKNOWN] = DT_UNKNOWN,
260 [EXT2_FT_REG_FILE] = DT_REG,
261 [EXT2_FT_DIR] = DT_DIR,
262 [EXT2_FT_CHRDEV] = DT_CHR,
263 [EXT2_FT_BLKDEV] = DT_BLK,
264 [EXT2_FT_FIFO] = DT_FIFO,
265 [EXT2_FT_SOCK] = DT_SOCK,
266 [EXT2_FT_SYMLINK] = DT_LNK,
267};
268
269#define S_SHIFT 12
270static unsigned char ext2_type_by_mode[S_IFMT >> S_SHIFT] = {
271 [S_IFREG >> S_SHIFT] = EXT2_FT_REG_FILE,
272 [S_IFDIR >> S_SHIFT] = EXT2_FT_DIR,
273 [S_IFCHR >> S_SHIFT] = EXT2_FT_CHRDEV,
274 [S_IFBLK >> S_SHIFT] = EXT2_FT_BLKDEV,
275 [S_IFIFO >> S_SHIFT] = EXT2_FT_FIFO,
276 [S_IFSOCK >> S_SHIFT] = EXT2_FT_SOCK,
277 [S_IFLNK >> S_SHIFT] = EXT2_FT_SYMLINK,
278};
279
280static inline void ext2_set_de_type(ext2_dirent *de, struct inode *inode)
281{
282 mode_t mode = inode->i_mode;
283 if (EXT2_HAS_INCOMPAT_FEATURE(inode->i_sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
284 de->file_type = ext2_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
285 else
286 de->file_type = 0;
287}
288
289static int
290ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
291{
292 loff_t pos = filp->f_pos;
293 struct inode *inode = filp->f_path.dentry->d_inode;
294 struct super_block *sb = inode->i_sb;
295 unsigned int offset = pos & ~PAGE_CACHE_MASK;
296 unsigned long n = pos >> PAGE_CACHE_SHIFT;
297 unsigned long npages = dir_pages(inode);
298 unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
299 unsigned char *types = NULL;
300 int need_revalidate = filp->f_version != inode->i_version;
301
302 if (pos > inode->i_size - EXT2_DIR_REC_LEN(1))
303 return 0;
304
305 if (EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
306 types = ext2_filetype_table;
307
308 for ( ; n < npages; n++, offset = 0) {
309 char *kaddr, *limit;
310 ext2_dirent *de;
311 struct page *page = ext2_get_page(inode, n, 0);
312
313 if (IS_ERR(page)) {
314 ext2_error(sb, __func__,
315 "bad page in #%lu",
316 inode->i_ino);
317 filp->f_pos += PAGE_CACHE_SIZE - offset;
318 return PTR_ERR(page);
319 }
320 kaddr = page_address(page);
321 if (unlikely(need_revalidate)) {
322 if (offset) {
323 offset = ext2_validate_entry(kaddr, offset, chunk_mask);
324 filp->f_pos = (n<<PAGE_CACHE_SHIFT) + offset;
325 }
326 filp->f_version = inode->i_version;
327 need_revalidate = 0;
328 }
329 de = (ext2_dirent *)(kaddr+offset);
330 limit = kaddr + ext2_last_byte(inode, n) - EXT2_DIR_REC_LEN(1);
331 for ( ;(char*)de <= limit; de = ext2_next_entry(de)) {
332 if (de->rec_len == 0) {
333 ext2_error(sb, __func__,
334 "zero-length directory entry");
335 ext2_put_page(page);
336 return -EIO;
337 }
338 if (de->inode) {
339 int over;
340 unsigned char d_type = DT_UNKNOWN;
341
342 if (types && de->file_type < EXT2_FT_MAX)
343 d_type = types[de->file_type];
344
345 offset = (char *)de - kaddr;
346 over = filldir(dirent, de->name, de->name_len,
347 (n<<PAGE_CACHE_SHIFT) | offset,
348 le32_to_cpu(de->inode), d_type);
349 if (over) {
350 ext2_put_page(page);
351 return 0;
352 }
353 }
354 filp->f_pos += ext2_rec_len_from_disk(de->rec_len);
355 }
356 ext2_put_page(page);
357 }
358 return 0;
359}
360
361/*
362 * ext2_find_entry()
363 *
364 * finds an entry in the specified directory with the wanted name. It
365 * returns the page in which the entry was found (as a parameter - res_page),
366 * and the entry itself. Page is returned mapped and unlocked.
367 * Entry is guaranteed to be valid.
368 */
369struct ext2_dir_entry_2 *ext2_find_entry (struct inode * dir,
370 struct qstr *child, struct page ** res_page)
371{
372 const char *name = child->name;
373 int namelen = child->len;
374 unsigned reclen = EXT2_DIR_REC_LEN(namelen);
375 unsigned long start, n;
376 unsigned long npages = dir_pages(dir);
377 struct page *page = NULL;
378 struct ext2_inode_info *ei = EXT2_I(dir);
379 ext2_dirent * de;
380 int dir_has_error = 0;
381
382 if (npages == 0)
383 goto out;
384
385 /* OFFSET_CACHE */
386 *res_page = NULL;
387
388 start = ei->i_dir_start_lookup;
389 if (start >= npages)
390 start = 0;
391 n = start;
392 do {
393 char *kaddr;
394 page = ext2_get_page(dir, n, dir_has_error);
395 if (!IS_ERR(page)) {
396 kaddr = page_address(page);
397 de = (ext2_dirent *) kaddr;
398 kaddr += ext2_last_byte(dir, n) - reclen;
399 while ((char *) de <= kaddr) {
400 if (de->rec_len == 0) {
401 ext2_error(dir->i_sb, __func__,
402 "zero-length directory entry");
403 ext2_put_page(page);
404 goto out;
405 }
406 if (ext2_match (namelen, name, de))
407 goto found;
408 de = ext2_next_entry(de);
409 }
410 ext2_put_page(page);
411 } else
412 dir_has_error = 1;
413
414 if (++n >= npages)
415 n = 0;
416 /* next page is past the blocks we've got */
417 if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) {
418 ext2_error(dir->i_sb, __func__,
419 "dir %lu size %lld exceeds block count %llu",
420 dir->i_ino, dir->i_size,
421 (unsigned long long)dir->i_blocks);
422 goto out;
423 }
424 } while (n != start);
425out:
426 return NULL;
427
428found:
429 *res_page = page;
430 ei->i_dir_start_lookup = n;
431 return de;
432}
433
434struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p)
435{
436 struct page *page = ext2_get_page(dir, 0, 0);
437 ext2_dirent *de = NULL;
438
439 if (!IS_ERR(page)) {
440 de = ext2_next_entry((ext2_dirent *) page_address(page));
441 *p = page;
442 }
443 return de;
444}
445
446ino_t ext2_inode_by_name(struct inode *dir, struct qstr *child)
447{
448 ino_t res = 0;
449 struct ext2_dir_entry_2 *de;
450 struct page *page;
451
452 de = ext2_find_entry (dir, child, &page);
453 if (de) {
454 res = le32_to_cpu(de->inode);
455 ext2_put_page(page);
456 }
457 return res;
458}
459
460static int ext2_prepare_chunk(struct page *page, loff_t pos, unsigned len)
461{
462 return __block_write_begin(page, pos, len, ext2_get_block);
463}
464
465/* Releases the page */
466void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
467 struct page *page, struct inode *inode, int update_times)
468{
469 loff_t pos = page_offset(page) +
470 (char *) de - (char *) page_address(page);
471 unsigned len = ext2_rec_len_from_disk(de->rec_len);
472 int err;
473
474 lock_page(page);
475 err = ext2_prepare_chunk(page, pos, len);
476 BUG_ON(err);
477 de->inode = cpu_to_le32(inode->i_ino);
478 ext2_set_de_type(de, inode);
479 err = ext2_commit_chunk(page, pos, len);
480 ext2_put_page(page);
481 if (update_times)
482 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
483 EXT2_I(dir)->i_flags &= ~EXT2_BTREE_FL;
484 mark_inode_dirty(dir);
485}
486
487/*
488 * Parent is locked.
489 */
490int ext2_add_link (struct dentry *dentry, struct inode *inode)
491{
492 struct inode *dir = dentry->d_parent->d_inode;
493 const char *name = dentry->d_name.name;
494 int namelen = dentry->d_name.len;
495 unsigned chunk_size = ext2_chunk_size(dir);
496 unsigned reclen = EXT2_DIR_REC_LEN(namelen);
497 unsigned short rec_len, name_len;
498 struct page *page = NULL;
499 ext2_dirent * de;
500 unsigned long npages = dir_pages(dir);
501 unsigned long n;
502 char *kaddr;
503 loff_t pos;
504 int err;
505
506 /*
507 * We take care of directory expansion in the same loop.
508 * This code plays outside i_size, so it locks the page
509 * to protect that region.
510 */
511 for (n = 0; n <= npages; n++) {
512 char *dir_end;
513
514 page = ext2_get_page(dir, n, 0);
515 err = PTR_ERR(page);
516 if (IS_ERR(page))
517 goto out;
518 lock_page(page);
519 kaddr = page_address(page);
520 dir_end = kaddr + ext2_last_byte(dir, n);
521 de = (ext2_dirent *)kaddr;
522 kaddr += PAGE_CACHE_SIZE - reclen;
523 while ((char *)de <= kaddr) {
524 if ((char *)de == dir_end) {
525 /* We hit i_size */
526 name_len = 0;
527 rec_len = chunk_size;
528 de->rec_len = ext2_rec_len_to_disk(chunk_size);
529 de->inode = 0;
530 goto got_it;
531 }
532 if (de->rec_len == 0) {
533 ext2_error(dir->i_sb, __func__,
534 "zero-length directory entry");
535 err = -EIO;
536 goto out_unlock;
537 }
538 err = -EEXIST;
539 if (ext2_match (namelen, name, de))
540 goto out_unlock;
541 name_len = EXT2_DIR_REC_LEN(de->name_len);
542 rec_len = ext2_rec_len_from_disk(de->rec_len);
543 if (!de->inode && rec_len >= reclen)
544 goto got_it;
545 if (rec_len >= name_len + reclen)
546 goto got_it;
547 de = (ext2_dirent *) ((char *) de + rec_len);
548 }
549 unlock_page(page);
550 ext2_put_page(page);
551 }
552 BUG();
553 return -EINVAL;
554
555got_it:
556 pos = page_offset(page) +
557 (char*)de - (char*)page_address(page);
558 err = ext2_prepare_chunk(page, pos, rec_len);
559 if (err)
560 goto out_unlock;
561 if (de->inode) {
562 ext2_dirent *de1 = (ext2_dirent *) ((char *) de + name_len);
563 de1->rec_len = ext2_rec_len_to_disk(rec_len - name_len);
564 de->rec_len = ext2_rec_len_to_disk(name_len);
565 de = de1;
566 }
567 de->name_len = namelen;
568 memcpy(de->name, name, namelen);
569 de->inode = cpu_to_le32(inode->i_ino);
570 ext2_set_de_type (de, inode);
571 err = ext2_commit_chunk(page, pos, rec_len);
572 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
573 EXT2_I(dir)->i_flags &= ~EXT2_BTREE_FL;
574 mark_inode_dirty(dir);
575 /* OFFSET_CACHE */
576out_put:
577 ext2_put_page(page);
578out:
579 return err;
580out_unlock:
581 unlock_page(page);
582 goto out_put;
583}
584
585/*
586 * ext2_delete_entry deletes a directory entry by merging it with the
587 * previous entry. Page is up-to-date. Releases the page.
588 */
589int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
590{
591 struct inode *inode = page->mapping->host;
592 char *kaddr = page_address(page);
593 unsigned from = ((char*)dir - kaddr) & ~(ext2_chunk_size(inode)-1);
594 unsigned to = ((char *)dir - kaddr) +
595 ext2_rec_len_from_disk(dir->rec_len);
596 loff_t pos;
597 ext2_dirent * pde = NULL;
598 ext2_dirent * de = (ext2_dirent *) (kaddr + from);
599 int err;
600
601 while ((char*)de < (char*)dir) {
602 if (de->rec_len == 0) {
603 ext2_error(inode->i_sb, __func__,
604 "zero-length directory entry");
605 err = -EIO;
606 goto out;
607 }
608 pde = de;
609 de = ext2_next_entry(de);
610 }
611 if (pde)
612 from = (char*)pde - (char*)page_address(page);
613 pos = page_offset(page) + from;
614 lock_page(page);
615 err = ext2_prepare_chunk(page, pos, to - from);
616 BUG_ON(err);
617 if (pde)
618 pde->rec_len = ext2_rec_len_to_disk(to - from);
619 dir->inode = 0;
620 err = ext2_commit_chunk(page, pos, to - from);
621 inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
622 EXT2_I(inode)->i_flags &= ~EXT2_BTREE_FL;
623 mark_inode_dirty(inode);
624out:
625 ext2_put_page(page);
626 return err;
627}
628
629/*
630 * Set the first fragment of directory.
631 */
632int ext2_make_empty(struct inode *inode, struct inode *parent)
633{
634 struct page *page = grab_cache_page(inode->i_mapping, 0);
635 unsigned chunk_size = ext2_chunk_size(inode);
636 struct ext2_dir_entry_2 * de;
637 int err;
638 void *kaddr;
639
640 if (!page)
641 return -ENOMEM;
642
643 err = ext2_prepare_chunk(page, 0, chunk_size);
644 if (err) {
645 unlock_page(page);
646 goto fail;
647 }
648 kaddr = kmap_atomic(page, KM_USER0);
649 memset(kaddr, 0, chunk_size);
650 de = (struct ext2_dir_entry_2 *)kaddr;
651 de->name_len = 1;
652 de->rec_len = ext2_rec_len_to_disk(EXT2_DIR_REC_LEN(1));
653 memcpy (de->name, ".\0\0", 4);
654 de->inode = cpu_to_le32(inode->i_ino);
655 ext2_set_de_type (de, inode);
656
657 de = (struct ext2_dir_entry_2 *)(kaddr + EXT2_DIR_REC_LEN(1));
658 de->name_len = 2;
659 de->rec_len = ext2_rec_len_to_disk(chunk_size - EXT2_DIR_REC_LEN(1));
660 de->inode = cpu_to_le32(parent->i_ino);
661 memcpy (de->name, "..\0", 4);
662 ext2_set_de_type (de, inode);
663 kunmap_atomic(kaddr, KM_USER0);
664 err = ext2_commit_chunk(page, 0, chunk_size);
665fail:
666 page_cache_release(page);
667 return err;
668}
669
670/*
671 * routine to check that the specified directory is empty (for rmdir)
672 */
673int ext2_empty_dir (struct inode * inode)
674{
675 struct page *page = NULL;
676 unsigned long i, npages = dir_pages(inode);
677 int dir_has_error = 0;
678
679 for (i = 0; i < npages; i++) {
680 char *kaddr;
681 ext2_dirent * de;
682 page = ext2_get_page(inode, i, dir_has_error);
683
684 if (IS_ERR(page)) {
685 dir_has_error = 1;
686 continue;
687 }
688
689 kaddr = page_address(page);
690 de = (ext2_dirent *)kaddr;
691 kaddr += ext2_last_byte(inode, i) - EXT2_DIR_REC_LEN(1);
692
693 while ((char *)de <= kaddr) {
694 if (de->rec_len == 0) {
695 ext2_error(inode->i_sb, __func__,
696 "zero-length directory entry");
697 printk("kaddr=%p, de=%p\n", kaddr, de);
698 goto not_empty;
699 }
700 if (de->inode != 0) {
701 /* check for . and .. */
702 if (de->name[0] != '.')
703 goto not_empty;
704 if (de->name_len > 2)
705 goto not_empty;
706 if (de->name_len < 2) {
707 if (de->inode !=
708 cpu_to_le32(inode->i_ino))
709 goto not_empty;
710 } else if (de->name[1] != '.')
711 goto not_empty;
712 }
713 de = ext2_next_entry(de);
714 }
715 ext2_put_page(page);
716 }
717 return 1;
718
719not_empty:
720 ext2_put_page(page);
721 return 0;
722}
723
724const struct file_operations ext2_dir_operations = {
725 .llseek = generic_file_llseek,
726 .read = generic_read_dir,
727 .readdir = ext2_readdir,
728 .unlocked_ioctl = ext2_ioctl,
729#ifdef CONFIG_COMPAT
730 .compat_ioctl = ext2_compat_ioctl,
731#endif
732 .fsync = ext2_fsync,
733};