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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * fs/f2fs/dir.c
4 *
5 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6 * http://www.samsung.com/
7 */
8#include <asm/unaligned.h>
9#include <linux/fs.h>
10#include <linux/f2fs_fs.h>
11#include <linux/sched/signal.h>
12#include <linux/unicode.h>
13#include "f2fs.h"
14#include "node.h"
15#include "acl.h"
16#include "xattr.h"
17#include <trace/events/f2fs.h>
18
19#if IS_ENABLED(CONFIG_UNICODE)
20extern struct kmem_cache *f2fs_cf_name_slab;
21#endif
22
23static unsigned long dir_blocks(struct inode *inode)
24{
25 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
26 >> PAGE_SHIFT;
27}
28
29static unsigned int dir_buckets(unsigned int level, int dir_level)
30{
31 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
32 return BIT(level + dir_level);
33 else
34 return MAX_DIR_BUCKETS;
35}
36
37static unsigned int bucket_blocks(unsigned int level)
38{
39 if (level < MAX_DIR_HASH_DEPTH / 2)
40 return 2;
41 else
42 return 4;
43}
44
45/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */
46int f2fs_init_casefolded_name(const struct inode *dir,
47 struct f2fs_filename *fname)
48{
49#if IS_ENABLED(CONFIG_UNICODE)
50 struct super_block *sb = dir->i_sb;
51
52 if (IS_CASEFOLDED(dir) &&
53 !is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
54 fname->cf_name.name = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
55 GFP_NOFS, false, F2FS_SB(sb));
56 if (!fname->cf_name.name)
57 return -ENOMEM;
58 fname->cf_name.len = utf8_casefold(sb->s_encoding,
59 fname->usr_fname,
60 fname->cf_name.name,
61 F2FS_NAME_LEN);
62 if ((int)fname->cf_name.len <= 0) {
63 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
64 fname->cf_name.name = NULL;
65 if (sb_has_strict_encoding(sb))
66 return -EINVAL;
67 /* fall back to treating name as opaque byte sequence */
68 }
69 }
70#endif
71 return 0;
72}
73
74static int __f2fs_setup_filename(const struct inode *dir,
75 const struct fscrypt_name *crypt_name,
76 struct f2fs_filename *fname)
77{
78 int err;
79
80 memset(fname, 0, sizeof(*fname));
81
82 fname->usr_fname = crypt_name->usr_fname;
83 fname->disk_name = crypt_name->disk_name;
84#ifdef CONFIG_FS_ENCRYPTION
85 fname->crypto_buf = crypt_name->crypto_buf;
86#endif
87 if (crypt_name->is_nokey_name) {
88 /* hash was decoded from the no-key name */
89 fname->hash = cpu_to_le32(crypt_name->hash);
90 } else {
91 err = f2fs_init_casefolded_name(dir, fname);
92 if (err) {
93 f2fs_free_filename(fname);
94 return err;
95 }
96 f2fs_hash_filename(dir, fname);
97 }
98 return 0;
99}
100
101/*
102 * Prepare to search for @iname in @dir. This is similar to
103 * fscrypt_setup_filename(), but this also handles computing the casefolded name
104 * and the f2fs dirhash if needed, then packing all the information about this
105 * filename up into a 'struct f2fs_filename'.
106 */
107int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
108 int lookup, struct f2fs_filename *fname)
109{
110 struct fscrypt_name crypt_name;
111 int err;
112
113 err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);
114 if (err)
115 return err;
116
117 return __f2fs_setup_filename(dir, &crypt_name, fname);
118}
119
120/*
121 * Prepare to look up @dentry in @dir. This is similar to
122 * fscrypt_prepare_lookup(), but this also handles computing the casefolded name
123 * and the f2fs dirhash if needed, then packing all the information about this
124 * filename up into a 'struct f2fs_filename'.
125 */
126int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,
127 struct f2fs_filename *fname)
128{
129 struct fscrypt_name crypt_name;
130 int err;
131
132 err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);
133 if (err)
134 return err;
135
136 return __f2fs_setup_filename(dir, &crypt_name, fname);
137}
138
139void f2fs_free_filename(struct f2fs_filename *fname)
140{
141#ifdef CONFIG_FS_ENCRYPTION
142 kfree(fname->crypto_buf.name);
143 fname->crypto_buf.name = NULL;
144#endif
145#if IS_ENABLED(CONFIG_UNICODE)
146 if (fname->cf_name.name) {
147 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
148 fname->cf_name.name = NULL;
149 }
150#endif
151}
152
153static unsigned long dir_block_index(unsigned int level,
154 int dir_level, unsigned int idx)
155{
156 unsigned long i;
157 unsigned long bidx = 0;
158
159 for (i = 0; i < level; i++)
160 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
161 bidx += idx * bucket_blocks(level);
162 return bidx;
163}
164
165static struct f2fs_dir_entry *find_in_block(struct inode *dir,
166 struct page *dentry_page,
167 const struct f2fs_filename *fname,
168 int *max_slots)
169{
170 struct f2fs_dentry_block *dentry_blk;
171 struct f2fs_dentry_ptr d;
172
173 dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);
174
175 make_dentry_ptr_block(dir, &d, dentry_blk);
176 return f2fs_find_target_dentry(&d, fname, max_slots);
177}
178
179#if IS_ENABLED(CONFIG_UNICODE)
180/*
181 * Test whether a case-insensitive directory entry matches the filename
182 * being searched for.
183 *
184 * Returns 1 for a match, 0 for no match, and -errno on an error.
185 */
186static int f2fs_match_ci_name(const struct inode *dir, const struct qstr *name,
187 const u8 *de_name, u32 de_name_len)
188{
189 const struct super_block *sb = dir->i_sb;
190 const struct unicode_map *um = sb->s_encoding;
191 struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
192 struct qstr entry = QSTR_INIT(de_name, de_name_len);
193 int res;
194
195 if (IS_ENCRYPTED(dir)) {
196 const struct fscrypt_str encrypted_name =
197 FSTR_INIT((u8 *)de_name, de_name_len);
198
199 if (WARN_ON_ONCE(!fscrypt_has_encryption_key(dir)))
200 return -EINVAL;
201
202 decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
203 if (!decrypted_name.name)
204 return -ENOMEM;
205 res = fscrypt_fname_disk_to_usr(dir, 0, 0, &encrypted_name,
206 &decrypted_name);
207 if (res < 0)
208 goto out;
209 entry.name = decrypted_name.name;
210 entry.len = decrypted_name.len;
211 }
212
213 res = utf8_strncasecmp_folded(um, name, &entry);
214 /*
215 * In strict mode, ignore invalid names. In non-strict mode,
216 * fall back to treating them as opaque byte sequences.
217 */
218 if (res < 0 && !sb_has_strict_encoding(sb)) {
219 res = name->len == entry.len &&
220 memcmp(name->name, entry.name, name->len) == 0;
221 } else {
222 /* utf8_strncasecmp_folded returns 0 on match */
223 res = (res == 0);
224 }
225out:
226 kfree(decrypted_name.name);
227 return res;
228}
229#endif /* CONFIG_UNICODE */
230
231static inline int f2fs_match_name(const struct inode *dir,
232 const struct f2fs_filename *fname,
233 const u8 *de_name, u32 de_name_len)
234{
235 struct fscrypt_name f;
236
237#if IS_ENABLED(CONFIG_UNICODE)
238 if (fname->cf_name.name) {
239 struct qstr cf = FSTR_TO_QSTR(&fname->cf_name);
240
241 return f2fs_match_ci_name(dir, &cf, de_name, de_name_len);
242 }
243#endif
244 f.usr_fname = fname->usr_fname;
245 f.disk_name = fname->disk_name;
246#ifdef CONFIG_FS_ENCRYPTION
247 f.crypto_buf = fname->crypto_buf;
248#endif
249 return fscrypt_match_name(&f, de_name, de_name_len);
250}
251
252struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
253 const struct f2fs_filename *fname, int *max_slots)
254{
255 struct f2fs_dir_entry *de;
256 unsigned long bit_pos = 0;
257 int max_len = 0;
258 int res = 0;
259
260 if (max_slots)
261 *max_slots = 0;
262 while (bit_pos < d->max) {
263 if (!test_bit_le(bit_pos, d->bitmap)) {
264 bit_pos++;
265 max_len++;
266 continue;
267 }
268
269 de = &d->dentry[bit_pos];
270
271 if (unlikely(!de->name_len)) {
272 bit_pos++;
273 continue;
274 }
275
276 if (de->hash_code == fname->hash) {
277 res = f2fs_match_name(d->inode, fname,
278 d->filename[bit_pos],
279 le16_to_cpu(de->name_len));
280 if (res < 0)
281 return ERR_PTR(res);
282 if (res)
283 goto found;
284 }
285
286 if (max_slots && max_len > *max_slots)
287 *max_slots = max_len;
288 max_len = 0;
289
290 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
291 }
292
293 de = NULL;
294found:
295 if (max_slots && max_len > *max_slots)
296 *max_slots = max_len;
297 return de;
298}
299
300static struct f2fs_dir_entry *find_in_level(struct inode *dir,
301 unsigned int level,
302 const struct f2fs_filename *fname,
303 struct page **res_page)
304{
305 int s = GET_DENTRY_SLOTS(fname->disk_name.len);
306 unsigned int nbucket, nblock;
307 unsigned int bidx, end_block;
308 struct page *dentry_page;
309 struct f2fs_dir_entry *de = NULL;
310 pgoff_t next_pgofs;
311 bool room = false;
312 int max_slots;
313
314 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
315 nblock = bucket_blocks(level);
316
317 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
318 le32_to_cpu(fname->hash) % nbucket);
319 end_block = bidx + nblock;
320
321 while (bidx < end_block) {
322 /* no need to allocate new dentry pages to all the indices */
323 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
324 if (IS_ERR(dentry_page)) {
325 if (PTR_ERR(dentry_page) == -ENOENT) {
326 room = true;
327 bidx = next_pgofs;
328 continue;
329 } else {
330 *res_page = dentry_page;
331 break;
332 }
333 }
334
335 de = find_in_block(dir, dentry_page, fname, &max_slots);
336 if (IS_ERR(de)) {
337 *res_page = ERR_CAST(de);
338 de = NULL;
339 break;
340 } else if (de) {
341 *res_page = dentry_page;
342 break;
343 }
344
345 if (max_slots >= s)
346 room = true;
347 f2fs_put_page(dentry_page, 0);
348
349 bidx++;
350 }
351
352 if (!de && room && F2FS_I(dir)->chash != fname->hash) {
353 F2FS_I(dir)->chash = fname->hash;
354 F2FS_I(dir)->clevel = level;
355 }
356
357 return de;
358}
359
360struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
361 const struct f2fs_filename *fname,
362 struct page **res_page)
363{
364 unsigned long npages = dir_blocks(dir);
365 struct f2fs_dir_entry *de = NULL;
366 unsigned int max_depth;
367 unsigned int level;
368
369 *res_page = NULL;
370
371 if (f2fs_has_inline_dentry(dir)) {
372 de = f2fs_find_in_inline_dir(dir, fname, res_page);
373 goto out;
374 }
375
376 if (npages == 0)
377 goto out;
378
379 max_depth = F2FS_I(dir)->i_current_depth;
380 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
381 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
382 dir->i_ino, max_depth);
383 max_depth = MAX_DIR_HASH_DEPTH;
384 f2fs_i_depth_write(dir, max_depth);
385 }
386
387 for (level = 0; level < max_depth; level++) {
388 de = find_in_level(dir, level, fname, res_page);
389 if (de || IS_ERR(*res_page))
390 break;
391 }
392out:
393 /* This is to increase the speed of f2fs_create */
394 if (!de)
395 F2FS_I(dir)->task = current;
396 return de;
397}
398
399/*
400 * Find an entry in the specified directory with the wanted name.
401 * It returns the page where the entry was found (as a parameter - res_page),
402 * and the entry itself. Page is returned mapped and unlocked.
403 * Entry is guaranteed to be valid.
404 */
405struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
406 const struct qstr *child, struct page **res_page)
407{
408 struct f2fs_dir_entry *de = NULL;
409 struct f2fs_filename fname;
410 int err;
411
412 err = f2fs_setup_filename(dir, child, 1, &fname);
413 if (err) {
414 if (err == -ENOENT)
415 *res_page = NULL;
416 else
417 *res_page = ERR_PTR(err);
418 return NULL;
419 }
420
421 de = __f2fs_find_entry(dir, &fname, res_page);
422
423 f2fs_free_filename(&fname);
424 return de;
425}
426
427struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
428{
429 return f2fs_find_entry(dir, &dotdot_name, p);
430}
431
432ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
433 struct page **page)
434{
435 ino_t res = 0;
436 struct f2fs_dir_entry *de;
437
438 de = f2fs_find_entry(dir, qstr, page);
439 if (de) {
440 res = le32_to_cpu(de->ino);
441 f2fs_put_page(*page, 0);
442 }
443
444 return res;
445}
446
447void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
448 struct page *page, struct inode *inode)
449{
450 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
451
452 lock_page(page);
453 f2fs_wait_on_page_writeback(page, type, true, true);
454 de->ino = cpu_to_le32(inode->i_ino);
455 de->file_type = fs_umode_to_ftype(inode->i_mode);
456 set_page_dirty(page);
457
458 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
459 f2fs_mark_inode_dirty_sync(dir, false);
460 f2fs_put_page(page, 1);
461}
462
463static void init_dent_inode(struct inode *dir, struct inode *inode,
464 const struct f2fs_filename *fname,
465 struct page *ipage)
466{
467 struct f2fs_inode *ri;
468
469 if (!fname) /* tmpfile case? */
470 return;
471
472 f2fs_wait_on_page_writeback(ipage, NODE, true, true);
473
474 /* copy name info. to this inode page */
475 ri = F2FS_INODE(ipage);
476 ri->i_namelen = cpu_to_le32(fname->disk_name.len);
477 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
478 if (IS_ENCRYPTED(dir)) {
479 file_set_enc_name(inode);
480 /*
481 * Roll-forward recovery doesn't have encryption keys available,
482 * so it can't compute the dirhash for encrypted+casefolded
483 * filenames. Append it to i_name if possible. Else, disable
484 * roll-forward recovery of the dentry (i.e., make fsync'ing the
485 * file force a checkpoint) by setting LOST_PINO.
486 */
487 if (IS_CASEFOLDED(dir)) {
488 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
489 F2FS_NAME_LEN)
490 put_unaligned(fname->hash, (f2fs_hash_t *)
491 &ri->i_name[fname->disk_name.len]);
492 else
493 file_lost_pino(inode);
494 }
495 }
496 set_page_dirty(ipage);
497}
498
499void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
500 struct f2fs_dentry_ptr *d)
501{
502 struct fscrypt_str dot = FSTR_INIT(".", 1);
503 struct fscrypt_str dotdot = FSTR_INIT("..", 2);
504
505 /* update dirent of "." */
506 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
507
508 /* update dirent of ".." */
509 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
510}
511
512static int make_empty_dir(struct inode *inode,
513 struct inode *parent, struct page *page)
514{
515 struct page *dentry_page;
516 struct f2fs_dentry_block *dentry_blk;
517 struct f2fs_dentry_ptr d;
518
519 if (f2fs_has_inline_dentry(inode))
520 return f2fs_make_empty_inline_dir(inode, parent, page);
521
522 dentry_page = f2fs_get_new_data_page(inode, page, 0, true);
523 if (IS_ERR(dentry_page))
524 return PTR_ERR(dentry_page);
525
526 dentry_blk = page_address(dentry_page);
527
528 make_dentry_ptr_block(NULL, &d, dentry_blk);
529 f2fs_do_make_empty_dir(inode, parent, &d);
530
531 set_page_dirty(dentry_page);
532 f2fs_put_page(dentry_page, 1);
533 return 0;
534}
535
536struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
537 const struct f2fs_filename *fname, struct page *dpage)
538{
539 struct page *page;
540 int err;
541
542 if (is_inode_flag_set(inode, FI_NEW_INODE)) {
543 page = f2fs_new_inode_page(inode);
544 if (IS_ERR(page))
545 return page;
546
547 if (S_ISDIR(inode->i_mode)) {
548 /* in order to handle error case */
549 get_page(page);
550 err = make_empty_dir(inode, dir, page);
551 if (err) {
552 lock_page(page);
553 goto put_error;
554 }
555 put_page(page);
556 }
557
558 err = f2fs_init_acl(inode, dir, page, dpage);
559 if (err)
560 goto put_error;
561
562 err = f2fs_init_security(inode, dir,
563 fname ? fname->usr_fname : NULL, page);
564 if (err)
565 goto put_error;
566
567 if (IS_ENCRYPTED(inode)) {
568 err = fscrypt_set_context(inode, page);
569 if (err)
570 goto put_error;
571 }
572 } else {
573 page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);
574 if (IS_ERR(page))
575 return page;
576 }
577
578 init_dent_inode(dir, inode, fname, page);
579
580 /*
581 * This file should be checkpointed during fsync.
582 * We lost i_pino from now on.
583 */
584 if (is_inode_flag_set(inode, FI_INC_LINK)) {
585 if (!S_ISDIR(inode->i_mode))
586 file_lost_pino(inode);
587 /*
588 * If link the tmpfile to alias through linkat path,
589 * we should remove this inode from orphan list.
590 */
591 if (inode->i_nlink == 0)
592 f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
593 f2fs_i_links_write(inode, true);
594 }
595 return page;
596
597put_error:
598 clear_nlink(inode);
599 f2fs_update_inode(inode, page);
600 f2fs_put_page(page, 1);
601 return ERR_PTR(err);
602}
603
604void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
605 unsigned int current_depth)
606{
607 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
608 if (S_ISDIR(inode->i_mode))
609 f2fs_i_links_write(dir, true);
610 clear_inode_flag(inode, FI_NEW_INODE);
611 }
612 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
613 f2fs_mark_inode_dirty_sync(dir, false);
614
615 if (F2FS_I(dir)->i_current_depth != current_depth)
616 f2fs_i_depth_write(dir, current_depth);
617
618 if (inode && is_inode_flag_set(inode, FI_INC_LINK))
619 clear_inode_flag(inode, FI_INC_LINK);
620}
621
622int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
623{
624 int bit_start = 0;
625 int zero_start, zero_end;
626next:
627 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
628 if (zero_start >= max_slots)
629 return max_slots;
630
631 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
632 if (zero_end - zero_start >= slots)
633 return zero_start;
634
635 bit_start = zero_end + 1;
636
637 if (zero_end + 1 >= max_slots)
638 return max_slots;
639 goto next;
640}
641
642bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
643 const struct f2fs_filename *fname)
644{
645 struct f2fs_dentry_ptr d;
646 unsigned int bit_pos;
647 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
648
649 make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
650
651 bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
652
653 return bit_pos < d.max;
654}
655
656void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
657 const struct fscrypt_str *name, f2fs_hash_t name_hash,
658 unsigned int bit_pos)
659{
660 struct f2fs_dir_entry *de;
661 int slots = GET_DENTRY_SLOTS(name->len);
662 int i;
663
664 de = &d->dentry[bit_pos];
665 de->hash_code = name_hash;
666 de->name_len = cpu_to_le16(name->len);
667 memcpy(d->filename[bit_pos], name->name, name->len);
668 de->ino = cpu_to_le32(ino);
669 de->file_type = fs_umode_to_ftype(mode);
670 for (i = 0; i < slots; i++) {
671 __set_bit_le(bit_pos + i, (void *)d->bitmap);
672 /* avoid wrong garbage data for readdir */
673 if (i)
674 (de + i)->name_len = 0;
675 }
676}
677
678int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
679 struct inode *inode, nid_t ino, umode_t mode)
680{
681 unsigned int bit_pos;
682 unsigned int level;
683 unsigned int current_depth;
684 unsigned long bidx, block;
685 unsigned int nbucket, nblock;
686 struct page *dentry_page = NULL;
687 struct f2fs_dentry_block *dentry_blk = NULL;
688 struct f2fs_dentry_ptr d;
689 struct page *page = NULL;
690 int slots, err = 0;
691
692 level = 0;
693 slots = GET_DENTRY_SLOTS(fname->disk_name.len);
694
695 current_depth = F2FS_I(dir)->i_current_depth;
696 if (F2FS_I(dir)->chash == fname->hash) {
697 level = F2FS_I(dir)->clevel;
698 F2FS_I(dir)->chash = 0;
699 }
700
701start:
702 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))
703 return -ENOSPC;
704
705 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
706 return -ENOSPC;
707
708 /* Increase the depth, if required */
709 if (level == current_depth)
710 ++current_depth;
711
712 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
713 nblock = bucket_blocks(level);
714
715 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
716 (le32_to_cpu(fname->hash) % nbucket));
717
718 for (block = bidx; block <= (bidx + nblock - 1); block++) {
719 dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);
720 if (IS_ERR(dentry_page))
721 return PTR_ERR(dentry_page);
722
723 dentry_blk = page_address(dentry_page);
724 bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,
725 slots, NR_DENTRY_IN_BLOCK);
726 if (bit_pos < NR_DENTRY_IN_BLOCK)
727 goto add_dentry;
728
729 f2fs_put_page(dentry_page, 1);
730 }
731
732 /* Move to next level to find the empty slot for new dentry */
733 ++level;
734 goto start;
735add_dentry:
736 f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);
737
738 if (inode) {
739 f2fs_down_write(&F2FS_I(inode)->i_sem);
740 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
741 if (IS_ERR(page)) {
742 err = PTR_ERR(page);
743 goto fail;
744 }
745 }
746
747 make_dentry_ptr_block(NULL, &d, dentry_blk);
748 f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,
749 bit_pos);
750
751 set_page_dirty(dentry_page);
752
753 if (inode) {
754 f2fs_i_pino_write(inode, dir->i_ino);
755
756 /* synchronize inode page's data from inode cache */
757 if (is_inode_flag_set(inode, FI_NEW_INODE))
758 f2fs_update_inode(inode, page);
759
760 f2fs_put_page(page, 1);
761 }
762
763 f2fs_update_parent_metadata(dir, inode, current_depth);
764fail:
765 if (inode)
766 f2fs_up_write(&F2FS_I(inode)->i_sem);
767
768 f2fs_put_page(dentry_page, 1);
769
770 return err;
771}
772
773int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
774 struct inode *inode, nid_t ino, umode_t mode)
775{
776 int err = -EAGAIN;
777
778 if (f2fs_has_inline_dentry(dir)) {
779 /*
780 * Should get i_xattr_sem to keep the lock order:
781 * i_xattr_sem -> inode_page lock used by f2fs_setxattr.
782 */
783 f2fs_down_read(&F2FS_I(dir)->i_xattr_sem);
784 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
785 f2fs_up_read(&F2FS_I(dir)->i_xattr_sem);
786 }
787 if (err == -EAGAIN)
788 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
789
790 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
791 return err;
792}
793
794/*
795 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
796 * f2fs_unlock_op().
797 */
798int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
799 struct inode *inode, nid_t ino, umode_t mode)
800{
801 struct f2fs_filename fname;
802 struct page *page = NULL;
803 struct f2fs_dir_entry *de = NULL;
804 int err;
805
806 err = f2fs_setup_filename(dir, name, 0, &fname);
807 if (err)
808 return err;
809
810 /*
811 * An immature stackable filesystem shows a race condition between lookup
812 * and create. If we have same task when doing lookup and create, it's
813 * definitely fine as expected by VFS normally. Otherwise, let's just
814 * verify on-disk dentry one more time, which guarantees filesystem
815 * consistency more.
816 */
817 if (current != F2FS_I(dir)->task) {
818 de = __f2fs_find_entry(dir, &fname, &page);
819 F2FS_I(dir)->task = NULL;
820 }
821 if (de) {
822 f2fs_put_page(page, 0);
823 err = -EEXIST;
824 } else if (IS_ERR(page)) {
825 err = PTR_ERR(page);
826 } else {
827 err = f2fs_add_dentry(dir, &fname, inode, ino, mode);
828 }
829 f2fs_free_filename(&fname);
830 return err;
831}
832
833int f2fs_do_tmpfile(struct inode *inode, struct inode *dir,
834 struct f2fs_filename *fname)
835{
836 struct page *page;
837 int err = 0;
838
839 f2fs_down_write(&F2FS_I(inode)->i_sem);
840 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
841 if (IS_ERR(page)) {
842 err = PTR_ERR(page);
843 goto fail;
844 }
845 f2fs_put_page(page, 1);
846
847 clear_inode_flag(inode, FI_NEW_INODE);
848 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
849fail:
850 f2fs_up_write(&F2FS_I(inode)->i_sem);
851 return err;
852}
853
854void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
855{
856 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
857
858 f2fs_down_write(&F2FS_I(inode)->i_sem);
859
860 if (S_ISDIR(inode->i_mode))
861 f2fs_i_links_write(dir, false);
862 inode_set_ctime_current(inode);
863
864 f2fs_i_links_write(inode, false);
865 if (S_ISDIR(inode->i_mode)) {
866 f2fs_i_links_write(inode, false);
867 f2fs_i_size_write(inode, 0);
868 }
869 f2fs_up_write(&F2FS_I(inode)->i_sem);
870
871 if (inode->i_nlink == 0)
872 f2fs_add_orphan_inode(inode);
873 else
874 f2fs_release_orphan_inode(sbi);
875}
876
877/*
878 * It only removes the dentry from the dentry page, corresponding name
879 * entry in name page does not need to be touched during deletion.
880 */
881void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
882 struct inode *dir, struct inode *inode)
883{
884 struct f2fs_dentry_block *dentry_blk;
885 unsigned int bit_pos;
886 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
887 int i;
888
889 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
890
891 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
892 f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);
893
894 if (f2fs_has_inline_dentry(dir))
895 return f2fs_delete_inline_entry(dentry, page, dir, inode);
896
897 lock_page(page);
898 f2fs_wait_on_page_writeback(page, DATA, true, true);
899
900 dentry_blk = page_address(page);
901 bit_pos = dentry - dentry_blk->dentry;
902 for (i = 0; i < slots; i++)
903 __clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
904
905 /* Let's check and deallocate this dentry page */
906 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
907 NR_DENTRY_IN_BLOCK,
908 0);
909 set_page_dirty(page);
910
911 if (bit_pos == NR_DENTRY_IN_BLOCK &&
912 !f2fs_truncate_hole(dir, page->index, page->index + 1)) {
913 f2fs_clear_page_cache_dirty_tag(page);
914 clear_page_dirty_for_io(page);
915 ClearPageUptodate(page);
916 clear_page_private_all(page);
917
918 inode_dec_dirty_pages(dir);
919 f2fs_remove_dirty_inode(dir);
920 }
921 f2fs_put_page(page, 1);
922
923 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
924 f2fs_mark_inode_dirty_sync(dir, false);
925
926 if (inode)
927 f2fs_drop_nlink(dir, inode);
928}
929
930bool f2fs_empty_dir(struct inode *dir)
931{
932 unsigned long bidx = 0;
933 struct page *dentry_page;
934 unsigned int bit_pos;
935 struct f2fs_dentry_block *dentry_blk;
936 unsigned long nblock = dir_blocks(dir);
937
938 if (f2fs_has_inline_dentry(dir))
939 return f2fs_empty_inline_dir(dir);
940
941 while (bidx < nblock) {
942 pgoff_t next_pgofs;
943
944 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
945 if (IS_ERR(dentry_page)) {
946 if (PTR_ERR(dentry_page) == -ENOENT) {
947 bidx = next_pgofs;
948 continue;
949 } else {
950 return false;
951 }
952 }
953
954 dentry_blk = page_address(dentry_page);
955 if (bidx == 0)
956 bit_pos = 2;
957 else
958 bit_pos = 0;
959 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
960 NR_DENTRY_IN_BLOCK,
961 bit_pos);
962
963 f2fs_put_page(dentry_page, 0);
964
965 if (bit_pos < NR_DENTRY_IN_BLOCK)
966 return false;
967
968 bidx++;
969 }
970 return true;
971}
972
973int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
974 unsigned int start_pos, struct fscrypt_str *fstr)
975{
976 unsigned char d_type = DT_UNKNOWN;
977 unsigned int bit_pos;
978 struct f2fs_dir_entry *de = NULL;
979 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
980 struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
981 struct blk_plug plug;
982 bool readdir_ra = sbi->readdir_ra;
983 bool found_valid_dirent = false;
984 int err = 0;
985
986 bit_pos = ((unsigned long)ctx->pos % d->max);
987
988 if (readdir_ra)
989 blk_start_plug(&plug);
990
991 while (bit_pos < d->max) {
992 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
993 if (bit_pos >= d->max)
994 break;
995
996 de = &d->dentry[bit_pos];
997 if (de->name_len == 0) {
998 if (found_valid_dirent || !bit_pos) {
999 f2fs_warn_ratelimited(sbi,
1000 "invalid namelen(0), ino:%u, run fsck to fix.",
1001 le32_to_cpu(de->ino));
1002 set_sbi_flag(sbi, SBI_NEED_FSCK);
1003 }
1004 bit_pos++;
1005 ctx->pos = start_pos + bit_pos;
1006 continue;
1007 }
1008
1009 d_type = fs_ftype_to_dtype(de->file_type);
1010
1011 de_name.name = d->filename[bit_pos];
1012 de_name.len = le16_to_cpu(de->name_len);
1013
1014 /* check memory boundary before moving forward */
1015 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
1016 if (unlikely(bit_pos > d->max ||
1017 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
1018 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
1019 __func__, le16_to_cpu(de->name_len));
1020 set_sbi_flag(sbi, SBI_NEED_FSCK);
1021 err = -EFSCORRUPTED;
1022 f2fs_handle_error(sbi, ERROR_CORRUPTED_DIRENT);
1023 goto out;
1024 }
1025
1026 if (IS_ENCRYPTED(d->inode)) {
1027 int save_len = fstr->len;
1028
1029 err = fscrypt_fname_disk_to_usr(d->inode,
1030 (u32)le32_to_cpu(de->hash_code),
1031 0, &de_name, fstr);
1032 if (err)
1033 goto out;
1034
1035 de_name = *fstr;
1036 fstr->len = save_len;
1037 }
1038
1039 if (!dir_emit(ctx, de_name.name, de_name.len,
1040 le32_to_cpu(de->ino), d_type)) {
1041 err = 1;
1042 goto out;
1043 }
1044
1045 if (readdir_ra)
1046 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
1047
1048 ctx->pos = start_pos + bit_pos;
1049 found_valid_dirent = true;
1050 }
1051out:
1052 if (readdir_ra)
1053 blk_finish_plug(&plug);
1054 return err;
1055}
1056
1057static int f2fs_readdir(struct file *file, struct dir_context *ctx)
1058{
1059 struct inode *inode = file_inode(file);
1060 unsigned long npages = dir_blocks(inode);
1061 struct f2fs_dentry_block *dentry_blk = NULL;
1062 struct page *dentry_page = NULL;
1063 struct file_ra_state *ra = &file->f_ra;
1064 loff_t start_pos = ctx->pos;
1065 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
1066 struct f2fs_dentry_ptr d;
1067 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
1068 int err = 0;
1069
1070 if (IS_ENCRYPTED(inode)) {
1071 err = fscrypt_prepare_readdir(inode);
1072 if (err)
1073 goto out;
1074
1075 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);
1076 if (err < 0)
1077 goto out;
1078 }
1079
1080 if (f2fs_has_inline_dentry(inode)) {
1081 err = f2fs_read_inline_dir(file, ctx, &fstr);
1082 goto out_free;
1083 }
1084
1085 for (; n < npages; ctx->pos = n * NR_DENTRY_IN_BLOCK) {
1086 pgoff_t next_pgofs;
1087
1088 /* allow readdir() to be interrupted */
1089 if (fatal_signal_pending(current)) {
1090 err = -ERESTARTSYS;
1091 goto out_free;
1092 }
1093 cond_resched();
1094
1095 /* readahead for multi pages of dir */
1096 if (npages - n > 1 && !ra_has_index(ra, n))
1097 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
1098 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
1099
1100 dentry_page = f2fs_find_data_page(inode, n, &next_pgofs);
1101 if (IS_ERR(dentry_page)) {
1102 err = PTR_ERR(dentry_page);
1103 if (err == -ENOENT) {
1104 err = 0;
1105 n = next_pgofs;
1106 continue;
1107 } else {
1108 goto out_free;
1109 }
1110 }
1111
1112 dentry_blk = page_address(dentry_page);
1113
1114 make_dentry_ptr_block(inode, &d, dentry_blk);
1115
1116 err = f2fs_fill_dentries(ctx, &d,
1117 n * NR_DENTRY_IN_BLOCK, &fstr);
1118 if (err) {
1119 f2fs_put_page(dentry_page, 0);
1120 break;
1121 }
1122
1123 f2fs_put_page(dentry_page, 0);
1124
1125 n++;
1126 }
1127out_free:
1128 fscrypt_fname_free_buffer(&fstr);
1129out:
1130 trace_f2fs_readdir(inode, start_pos, ctx->pos, err);
1131 return err < 0 ? err : 0;
1132}
1133
1134const struct file_operations f2fs_dir_operations = {
1135 .llseek = generic_file_llseek,
1136 .read = generic_read_dir,
1137 .iterate_shared = f2fs_readdir,
1138 .fsync = f2fs_sync_file,
1139 .unlocked_ioctl = f2fs_ioctl,
1140#ifdef CONFIG_COMPAT
1141 .compat_ioctl = f2fs_compat_ioctl,
1142#endif
1143};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * fs/f2fs/dir.c
4 *
5 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6 * http://www.samsung.com/
7 */
8#include <asm/unaligned.h>
9#include <linux/fs.h>
10#include <linux/f2fs_fs.h>
11#include <linux/sched/signal.h>
12#include <linux/unicode.h>
13#include "f2fs.h"
14#include "node.h"
15#include "acl.h"
16#include "xattr.h"
17#include <trace/events/f2fs.h>
18
19#if IS_ENABLED(CONFIG_UNICODE)
20extern struct kmem_cache *f2fs_cf_name_slab;
21#endif
22
23static unsigned long dir_blocks(struct inode *inode)
24{
25 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
26 >> PAGE_SHIFT;
27}
28
29static unsigned int dir_buckets(unsigned int level, int dir_level)
30{
31 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
32 return 1 << (level + dir_level);
33 else
34 return MAX_DIR_BUCKETS;
35}
36
37static unsigned int bucket_blocks(unsigned int level)
38{
39 if (level < MAX_DIR_HASH_DEPTH / 2)
40 return 2;
41 else
42 return 4;
43}
44
45static unsigned char f2fs_filetype_table[F2FS_FT_MAX] = {
46 [F2FS_FT_UNKNOWN] = DT_UNKNOWN,
47 [F2FS_FT_REG_FILE] = DT_REG,
48 [F2FS_FT_DIR] = DT_DIR,
49 [F2FS_FT_CHRDEV] = DT_CHR,
50 [F2FS_FT_BLKDEV] = DT_BLK,
51 [F2FS_FT_FIFO] = DT_FIFO,
52 [F2FS_FT_SOCK] = DT_SOCK,
53 [F2FS_FT_SYMLINK] = DT_LNK,
54};
55
56static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
57 [S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE,
58 [S_IFDIR >> S_SHIFT] = F2FS_FT_DIR,
59 [S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV,
60 [S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV,
61 [S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO,
62 [S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK,
63 [S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK,
64};
65
66static void set_de_type(struct f2fs_dir_entry *de, umode_t mode)
67{
68 de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
69}
70
71unsigned char f2fs_get_de_type(struct f2fs_dir_entry *de)
72{
73 if (de->file_type < F2FS_FT_MAX)
74 return f2fs_filetype_table[de->file_type];
75 return DT_UNKNOWN;
76}
77
78/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */
79int f2fs_init_casefolded_name(const struct inode *dir,
80 struct f2fs_filename *fname)
81{
82#if IS_ENABLED(CONFIG_UNICODE)
83 struct super_block *sb = dir->i_sb;
84
85 if (IS_CASEFOLDED(dir) &&
86 !is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
87 fname->cf_name.name = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
88 GFP_NOFS, false, F2FS_SB(sb));
89 if (!fname->cf_name.name)
90 return -ENOMEM;
91 fname->cf_name.len = utf8_casefold(sb->s_encoding,
92 fname->usr_fname,
93 fname->cf_name.name,
94 F2FS_NAME_LEN);
95 if ((int)fname->cf_name.len <= 0) {
96 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
97 fname->cf_name.name = NULL;
98 if (sb_has_strict_encoding(sb))
99 return -EINVAL;
100 /* fall back to treating name as opaque byte sequence */
101 }
102 }
103#endif
104 return 0;
105}
106
107static int __f2fs_setup_filename(const struct inode *dir,
108 const struct fscrypt_name *crypt_name,
109 struct f2fs_filename *fname)
110{
111 int err;
112
113 memset(fname, 0, sizeof(*fname));
114
115 fname->usr_fname = crypt_name->usr_fname;
116 fname->disk_name = crypt_name->disk_name;
117#ifdef CONFIG_FS_ENCRYPTION
118 fname->crypto_buf = crypt_name->crypto_buf;
119#endif
120 if (crypt_name->is_nokey_name) {
121 /* hash was decoded from the no-key name */
122 fname->hash = cpu_to_le32(crypt_name->hash);
123 } else {
124 err = f2fs_init_casefolded_name(dir, fname);
125 if (err) {
126 f2fs_free_filename(fname);
127 return err;
128 }
129 f2fs_hash_filename(dir, fname);
130 }
131 return 0;
132}
133
134/*
135 * Prepare to search for @iname in @dir. This is similar to
136 * fscrypt_setup_filename(), but this also handles computing the casefolded name
137 * and the f2fs dirhash if needed, then packing all the information about this
138 * filename up into a 'struct f2fs_filename'.
139 */
140int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
141 int lookup, struct f2fs_filename *fname)
142{
143 struct fscrypt_name crypt_name;
144 int err;
145
146 err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);
147 if (err)
148 return err;
149
150 return __f2fs_setup_filename(dir, &crypt_name, fname);
151}
152
153/*
154 * Prepare to look up @dentry in @dir. This is similar to
155 * fscrypt_prepare_lookup(), but this also handles computing the casefolded name
156 * and the f2fs dirhash if needed, then packing all the information about this
157 * filename up into a 'struct f2fs_filename'.
158 */
159int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,
160 struct f2fs_filename *fname)
161{
162 struct fscrypt_name crypt_name;
163 int err;
164
165 err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);
166 if (err)
167 return err;
168
169 return __f2fs_setup_filename(dir, &crypt_name, fname);
170}
171
172void f2fs_free_filename(struct f2fs_filename *fname)
173{
174#ifdef CONFIG_FS_ENCRYPTION
175 kfree(fname->crypto_buf.name);
176 fname->crypto_buf.name = NULL;
177#endif
178#if IS_ENABLED(CONFIG_UNICODE)
179 if (fname->cf_name.name) {
180 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
181 fname->cf_name.name = NULL;
182 }
183#endif
184}
185
186static unsigned long dir_block_index(unsigned int level,
187 int dir_level, unsigned int idx)
188{
189 unsigned long i;
190 unsigned long bidx = 0;
191
192 for (i = 0; i < level; i++)
193 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
194 bidx += idx * bucket_blocks(level);
195 return bidx;
196}
197
198static struct f2fs_dir_entry *find_in_block(struct inode *dir,
199 struct page *dentry_page,
200 const struct f2fs_filename *fname,
201 int *max_slots)
202{
203 struct f2fs_dentry_block *dentry_blk;
204 struct f2fs_dentry_ptr d;
205
206 dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);
207
208 make_dentry_ptr_block(dir, &d, dentry_blk);
209 return f2fs_find_target_dentry(&d, fname, max_slots);
210}
211
212#if IS_ENABLED(CONFIG_UNICODE)
213/*
214 * Test whether a case-insensitive directory entry matches the filename
215 * being searched for.
216 *
217 * Returns 1 for a match, 0 for no match, and -errno on an error.
218 */
219static int f2fs_match_ci_name(const struct inode *dir, const struct qstr *name,
220 const u8 *de_name, u32 de_name_len)
221{
222 const struct super_block *sb = dir->i_sb;
223 const struct unicode_map *um = sb->s_encoding;
224 struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
225 struct qstr entry = QSTR_INIT(de_name, de_name_len);
226 int res;
227
228 if (IS_ENCRYPTED(dir)) {
229 const struct fscrypt_str encrypted_name =
230 FSTR_INIT((u8 *)de_name, de_name_len);
231
232 if (WARN_ON_ONCE(!fscrypt_has_encryption_key(dir)))
233 return -EINVAL;
234
235 decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
236 if (!decrypted_name.name)
237 return -ENOMEM;
238 res = fscrypt_fname_disk_to_usr(dir, 0, 0, &encrypted_name,
239 &decrypted_name);
240 if (res < 0)
241 goto out;
242 entry.name = decrypted_name.name;
243 entry.len = decrypted_name.len;
244 }
245
246 res = utf8_strncasecmp_folded(um, name, &entry);
247 /*
248 * In strict mode, ignore invalid names. In non-strict mode,
249 * fall back to treating them as opaque byte sequences.
250 */
251 if (res < 0 && !sb_has_strict_encoding(sb)) {
252 res = name->len == entry.len &&
253 memcmp(name->name, entry.name, name->len) == 0;
254 } else {
255 /* utf8_strncasecmp_folded returns 0 on match */
256 res = (res == 0);
257 }
258out:
259 kfree(decrypted_name.name);
260 return res;
261}
262#endif /* CONFIG_UNICODE */
263
264static inline int f2fs_match_name(const struct inode *dir,
265 const struct f2fs_filename *fname,
266 const u8 *de_name, u32 de_name_len)
267{
268 struct fscrypt_name f;
269
270#if IS_ENABLED(CONFIG_UNICODE)
271 if (fname->cf_name.name) {
272 struct qstr cf = FSTR_TO_QSTR(&fname->cf_name);
273
274 return f2fs_match_ci_name(dir, &cf, de_name, de_name_len);
275 }
276#endif
277 f.usr_fname = fname->usr_fname;
278 f.disk_name = fname->disk_name;
279#ifdef CONFIG_FS_ENCRYPTION
280 f.crypto_buf = fname->crypto_buf;
281#endif
282 return fscrypt_match_name(&f, de_name, de_name_len);
283}
284
285struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
286 const struct f2fs_filename *fname, int *max_slots)
287{
288 struct f2fs_dir_entry *de;
289 unsigned long bit_pos = 0;
290 int max_len = 0;
291 int res = 0;
292
293 if (max_slots)
294 *max_slots = 0;
295 while (bit_pos < d->max) {
296 if (!test_bit_le(bit_pos, d->bitmap)) {
297 bit_pos++;
298 max_len++;
299 continue;
300 }
301
302 de = &d->dentry[bit_pos];
303
304 if (unlikely(!de->name_len)) {
305 bit_pos++;
306 continue;
307 }
308
309 if (de->hash_code == fname->hash) {
310 res = f2fs_match_name(d->inode, fname,
311 d->filename[bit_pos],
312 le16_to_cpu(de->name_len));
313 if (res < 0)
314 return ERR_PTR(res);
315 if (res)
316 goto found;
317 }
318
319 if (max_slots && max_len > *max_slots)
320 *max_slots = max_len;
321 max_len = 0;
322
323 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
324 }
325
326 de = NULL;
327found:
328 if (max_slots && max_len > *max_slots)
329 *max_slots = max_len;
330 return de;
331}
332
333static struct f2fs_dir_entry *find_in_level(struct inode *dir,
334 unsigned int level,
335 const struct f2fs_filename *fname,
336 struct page **res_page)
337{
338 int s = GET_DENTRY_SLOTS(fname->disk_name.len);
339 unsigned int nbucket, nblock;
340 unsigned int bidx, end_block;
341 struct page *dentry_page;
342 struct f2fs_dir_entry *de = NULL;
343 pgoff_t next_pgofs;
344 bool room = false;
345 int max_slots;
346
347 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
348 nblock = bucket_blocks(level);
349
350 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
351 le32_to_cpu(fname->hash) % nbucket);
352 end_block = bidx + nblock;
353
354 while (bidx < end_block) {
355 /* no need to allocate new dentry pages to all the indices */
356 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
357 if (IS_ERR(dentry_page)) {
358 if (PTR_ERR(dentry_page) == -ENOENT) {
359 room = true;
360 bidx = next_pgofs;
361 continue;
362 } else {
363 *res_page = dentry_page;
364 break;
365 }
366 }
367
368 de = find_in_block(dir, dentry_page, fname, &max_slots);
369 if (IS_ERR(de)) {
370 *res_page = ERR_CAST(de);
371 de = NULL;
372 break;
373 } else if (de) {
374 *res_page = dentry_page;
375 break;
376 }
377
378 if (max_slots >= s)
379 room = true;
380 f2fs_put_page(dentry_page, 0);
381
382 bidx++;
383 }
384
385 if (!de && room && F2FS_I(dir)->chash != fname->hash) {
386 F2FS_I(dir)->chash = fname->hash;
387 F2FS_I(dir)->clevel = level;
388 }
389
390 return de;
391}
392
393struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
394 const struct f2fs_filename *fname,
395 struct page **res_page)
396{
397 unsigned long npages = dir_blocks(dir);
398 struct f2fs_dir_entry *de = NULL;
399 unsigned int max_depth;
400 unsigned int level;
401
402 *res_page = NULL;
403
404 if (f2fs_has_inline_dentry(dir)) {
405 de = f2fs_find_in_inline_dir(dir, fname, res_page);
406 goto out;
407 }
408
409 if (npages == 0)
410 goto out;
411
412 max_depth = F2FS_I(dir)->i_current_depth;
413 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
414 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
415 dir->i_ino, max_depth);
416 max_depth = MAX_DIR_HASH_DEPTH;
417 f2fs_i_depth_write(dir, max_depth);
418 }
419
420 for (level = 0; level < max_depth; level++) {
421 de = find_in_level(dir, level, fname, res_page);
422 if (de || IS_ERR(*res_page))
423 break;
424 }
425out:
426 /* This is to increase the speed of f2fs_create */
427 if (!de)
428 F2FS_I(dir)->task = current;
429 return de;
430}
431
432/*
433 * Find an entry in the specified directory with the wanted name.
434 * It returns the page where the entry was found (as a parameter - res_page),
435 * and the entry itself. Page is returned mapped and unlocked.
436 * Entry is guaranteed to be valid.
437 */
438struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
439 const struct qstr *child, struct page **res_page)
440{
441 struct f2fs_dir_entry *de = NULL;
442 struct f2fs_filename fname;
443 int err;
444
445 err = f2fs_setup_filename(dir, child, 1, &fname);
446 if (err) {
447 if (err == -ENOENT)
448 *res_page = NULL;
449 else
450 *res_page = ERR_PTR(err);
451 return NULL;
452 }
453
454 de = __f2fs_find_entry(dir, &fname, res_page);
455
456 f2fs_free_filename(&fname);
457 return de;
458}
459
460struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
461{
462 return f2fs_find_entry(dir, &dotdot_name, p);
463}
464
465ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
466 struct page **page)
467{
468 ino_t res = 0;
469 struct f2fs_dir_entry *de;
470
471 de = f2fs_find_entry(dir, qstr, page);
472 if (de) {
473 res = le32_to_cpu(de->ino);
474 f2fs_put_page(*page, 0);
475 }
476
477 return res;
478}
479
480void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
481 struct page *page, struct inode *inode)
482{
483 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
484
485 lock_page(page);
486 f2fs_wait_on_page_writeback(page, type, true, true);
487 de->ino = cpu_to_le32(inode->i_ino);
488 set_de_type(de, inode->i_mode);
489 set_page_dirty(page);
490
491 dir->i_mtime = dir->i_ctime = current_time(dir);
492 f2fs_mark_inode_dirty_sync(dir, false);
493 f2fs_put_page(page, 1);
494}
495
496static void init_dent_inode(struct inode *dir, struct inode *inode,
497 const struct f2fs_filename *fname,
498 struct page *ipage)
499{
500 struct f2fs_inode *ri;
501
502 if (!fname) /* tmpfile case? */
503 return;
504
505 f2fs_wait_on_page_writeback(ipage, NODE, true, true);
506
507 /* copy name info. to this inode page */
508 ri = F2FS_INODE(ipage);
509 ri->i_namelen = cpu_to_le32(fname->disk_name.len);
510 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
511 if (IS_ENCRYPTED(dir)) {
512 file_set_enc_name(inode);
513 /*
514 * Roll-forward recovery doesn't have encryption keys available,
515 * so it can't compute the dirhash for encrypted+casefolded
516 * filenames. Append it to i_name if possible. Else, disable
517 * roll-forward recovery of the dentry (i.e., make fsync'ing the
518 * file force a checkpoint) by setting LOST_PINO.
519 */
520 if (IS_CASEFOLDED(dir)) {
521 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
522 F2FS_NAME_LEN)
523 put_unaligned(fname->hash, (f2fs_hash_t *)
524 &ri->i_name[fname->disk_name.len]);
525 else
526 file_lost_pino(inode);
527 }
528 }
529 set_page_dirty(ipage);
530}
531
532void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
533 struct f2fs_dentry_ptr *d)
534{
535 struct fscrypt_str dot = FSTR_INIT(".", 1);
536 struct fscrypt_str dotdot = FSTR_INIT("..", 2);
537
538 /* update dirent of "." */
539 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
540
541 /* update dirent of ".." */
542 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
543}
544
545static int make_empty_dir(struct inode *inode,
546 struct inode *parent, struct page *page)
547{
548 struct page *dentry_page;
549 struct f2fs_dentry_block *dentry_blk;
550 struct f2fs_dentry_ptr d;
551
552 if (f2fs_has_inline_dentry(inode))
553 return f2fs_make_empty_inline_dir(inode, parent, page);
554
555 dentry_page = f2fs_get_new_data_page(inode, page, 0, true);
556 if (IS_ERR(dentry_page))
557 return PTR_ERR(dentry_page);
558
559 dentry_blk = page_address(dentry_page);
560
561 make_dentry_ptr_block(NULL, &d, dentry_blk);
562 f2fs_do_make_empty_dir(inode, parent, &d);
563
564 set_page_dirty(dentry_page);
565 f2fs_put_page(dentry_page, 1);
566 return 0;
567}
568
569struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
570 const struct f2fs_filename *fname, struct page *dpage)
571{
572 struct page *page;
573 int err;
574
575 if (is_inode_flag_set(inode, FI_NEW_INODE)) {
576 page = f2fs_new_inode_page(inode);
577 if (IS_ERR(page))
578 return page;
579
580 if (S_ISDIR(inode->i_mode)) {
581 /* in order to handle error case */
582 get_page(page);
583 err = make_empty_dir(inode, dir, page);
584 if (err) {
585 lock_page(page);
586 goto put_error;
587 }
588 put_page(page);
589 }
590
591 err = f2fs_init_acl(inode, dir, page, dpage);
592 if (err)
593 goto put_error;
594
595 err = f2fs_init_security(inode, dir,
596 fname ? fname->usr_fname : NULL, page);
597 if (err)
598 goto put_error;
599
600 if (IS_ENCRYPTED(inode)) {
601 err = fscrypt_set_context(inode, page);
602 if (err)
603 goto put_error;
604 }
605 } else {
606 page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);
607 if (IS_ERR(page))
608 return page;
609 }
610
611 init_dent_inode(dir, inode, fname, page);
612
613 /*
614 * This file should be checkpointed during fsync.
615 * We lost i_pino from now on.
616 */
617 if (is_inode_flag_set(inode, FI_INC_LINK)) {
618 if (!S_ISDIR(inode->i_mode))
619 file_lost_pino(inode);
620 /*
621 * If link the tmpfile to alias through linkat path,
622 * we should remove this inode from orphan list.
623 */
624 if (inode->i_nlink == 0)
625 f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
626 f2fs_i_links_write(inode, true);
627 }
628 return page;
629
630put_error:
631 clear_nlink(inode);
632 f2fs_update_inode(inode, page);
633 f2fs_put_page(page, 1);
634 return ERR_PTR(err);
635}
636
637void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
638 unsigned int current_depth)
639{
640 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
641 if (S_ISDIR(inode->i_mode))
642 f2fs_i_links_write(dir, true);
643 clear_inode_flag(inode, FI_NEW_INODE);
644 }
645 dir->i_mtime = dir->i_ctime = current_time(dir);
646 f2fs_mark_inode_dirty_sync(dir, false);
647
648 if (F2FS_I(dir)->i_current_depth != current_depth)
649 f2fs_i_depth_write(dir, current_depth);
650
651 if (inode && is_inode_flag_set(inode, FI_INC_LINK))
652 clear_inode_flag(inode, FI_INC_LINK);
653}
654
655int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
656{
657 int bit_start = 0;
658 int zero_start, zero_end;
659next:
660 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
661 if (zero_start >= max_slots)
662 return max_slots;
663
664 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
665 if (zero_end - zero_start >= slots)
666 return zero_start;
667
668 bit_start = zero_end + 1;
669
670 if (zero_end + 1 >= max_slots)
671 return max_slots;
672 goto next;
673}
674
675bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
676 const struct f2fs_filename *fname)
677{
678 struct f2fs_dentry_ptr d;
679 unsigned int bit_pos;
680 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
681
682 make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
683
684 bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
685
686 return bit_pos < d.max;
687}
688
689void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
690 const struct fscrypt_str *name, f2fs_hash_t name_hash,
691 unsigned int bit_pos)
692{
693 struct f2fs_dir_entry *de;
694 int slots = GET_DENTRY_SLOTS(name->len);
695 int i;
696
697 de = &d->dentry[bit_pos];
698 de->hash_code = name_hash;
699 de->name_len = cpu_to_le16(name->len);
700 memcpy(d->filename[bit_pos], name->name, name->len);
701 de->ino = cpu_to_le32(ino);
702 set_de_type(de, mode);
703 for (i = 0; i < slots; i++) {
704 __set_bit_le(bit_pos + i, (void *)d->bitmap);
705 /* avoid wrong garbage data for readdir */
706 if (i)
707 (de + i)->name_len = 0;
708 }
709}
710
711int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
712 struct inode *inode, nid_t ino, umode_t mode)
713{
714 unsigned int bit_pos;
715 unsigned int level;
716 unsigned int current_depth;
717 unsigned long bidx, block;
718 unsigned int nbucket, nblock;
719 struct page *dentry_page = NULL;
720 struct f2fs_dentry_block *dentry_blk = NULL;
721 struct f2fs_dentry_ptr d;
722 struct page *page = NULL;
723 int slots, err = 0;
724
725 level = 0;
726 slots = GET_DENTRY_SLOTS(fname->disk_name.len);
727
728 current_depth = F2FS_I(dir)->i_current_depth;
729 if (F2FS_I(dir)->chash == fname->hash) {
730 level = F2FS_I(dir)->clevel;
731 F2FS_I(dir)->chash = 0;
732 }
733
734start:
735 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH)) {
736 f2fs_show_injection_info(F2FS_I_SB(dir), FAULT_DIR_DEPTH);
737 return -ENOSPC;
738 }
739
740 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
741 return -ENOSPC;
742
743 /* Increase the depth, if required */
744 if (level == current_depth)
745 ++current_depth;
746
747 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
748 nblock = bucket_blocks(level);
749
750 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
751 (le32_to_cpu(fname->hash) % nbucket));
752
753 for (block = bidx; block <= (bidx + nblock - 1); block++) {
754 dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);
755 if (IS_ERR(dentry_page))
756 return PTR_ERR(dentry_page);
757
758 dentry_blk = page_address(dentry_page);
759 bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,
760 slots, NR_DENTRY_IN_BLOCK);
761 if (bit_pos < NR_DENTRY_IN_BLOCK)
762 goto add_dentry;
763
764 f2fs_put_page(dentry_page, 1);
765 }
766
767 /* Move to next level to find the empty slot for new dentry */
768 ++level;
769 goto start;
770add_dentry:
771 f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);
772
773 if (inode) {
774 f2fs_down_write(&F2FS_I(inode)->i_sem);
775 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
776 if (IS_ERR(page)) {
777 err = PTR_ERR(page);
778 goto fail;
779 }
780 }
781
782 make_dentry_ptr_block(NULL, &d, dentry_blk);
783 f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,
784 bit_pos);
785
786 set_page_dirty(dentry_page);
787
788 if (inode) {
789 f2fs_i_pino_write(inode, dir->i_ino);
790
791 /* synchronize inode page's data from inode cache */
792 if (is_inode_flag_set(inode, FI_NEW_INODE))
793 f2fs_update_inode(inode, page);
794
795 f2fs_put_page(page, 1);
796 }
797
798 f2fs_update_parent_metadata(dir, inode, current_depth);
799fail:
800 if (inode)
801 f2fs_up_write(&F2FS_I(inode)->i_sem);
802
803 f2fs_put_page(dentry_page, 1);
804
805 return err;
806}
807
808int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
809 struct inode *inode, nid_t ino, umode_t mode)
810{
811 int err = -EAGAIN;
812
813 if (f2fs_has_inline_dentry(dir))
814 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
815 if (err == -EAGAIN)
816 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
817
818 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
819 return err;
820}
821
822/*
823 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
824 * f2fs_unlock_op().
825 */
826int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
827 struct inode *inode, nid_t ino, umode_t mode)
828{
829 struct f2fs_filename fname;
830 struct page *page = NULL;
831 struct f2fs_dir_entry *de = NULL;
832 int err;
833
834 err = f2fs_setup_filename(dir, name, 0, &fname);
835 if (err)
836 return err;
837
838 /*
839 * An immature stackable filesystem shows a race condition between lookup
840 * and create. If we have same task when doing lookup and create, it's
841 * definitely fine as expected by VFS normally. Otherwise, let's just
842 * verify on-disk dentry one more time, which guarantees filesystem
843 * consistency more.
844 */
845 if (current != F2FS_I(dir)->task) {
846 de = __f2fs_find_entry(dir, &fname, &page);
847 F2FS_I(dir)->task = NULL;
848 }
849 if (de) {
850 f2fs_put_page(page, 0);
851 err = -EEXIST;
852 } else if (IS_ERR(page)) {
853 err = PTR_ERR(page);
854 } else {
855 err = f2fs_add_dentry(dir, &fname, inode, ino, mode);
856 }
857 f2fs_free_filename(&fname);
858 return err;
859}
860
861int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
862{
863 struct page *page;
864 int err = 0;
865
866 f2fs_down_write(&F2FS_I(inode)->i_sem);
867 page = f2fs_init_inode_metadata(inode, dir, NULL, NULL);
868 if (IS_ERR(page)) {
869 err = PTR_ERR(page);
870 goto fail;
871 }
872 f2fs_put_page(page, 1);
873
874 clear_inode_flag(inode, FI_NEW_INODE);
875 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
876fail:
877 f2fs_up_write(&F2FS_I(inode)->i_sem);
878 return err;
879}
880
881void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
882{
883 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
884
885 f2fs_down_write(&F2FS_I(inode)->i_sem);
886
887 if (S_ISDIR(inode->i_mode))
888 f2fs_i_links_write(dir, false);
889 inode->i_ctime = current_time(inode);
890
891 f2fs_i_links_write(inode, false);
892 if (S_ISDIR(inode->i_mode)) {
893 f2fs_i_links_write(inode, false);
894 f2fs_i_size_write(inode, 0);
895 }
896 f2fs_up_write(&F2FS_I(inode)->i_sem);
897
898 if (inode->i_nlink == 0)
899 f2fs_add_orphan_inode(inode);
900 else
901 f2fs_release_orphan_inode(sbi);
902}
903
904/*
905 * It only removes the dentry from the dentry page, corresponding name
906 * entry in name page does not need to be touched during deletion.
907 */
908void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
909 struct inode *dir, struct inode *inode)
910{
911 struct f2fs_dentry_block *dentry_blk;
912 unsigned int bit_pos;
913 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
914 int i;
915
916 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
917
918 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
919 f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);
920
921 if (f2fs_has_inline_dentry(dir))
922 return f2fs_delete_inline_entry(dentry, page, dir, inode);
923
924 lock_page(page);
925 f2fs_wait_on_page_writeback(page, DATA, true, true);
926
927 dentry_blk = page_address(page);
928 bit_pos = dentry - dentry_blk->dentry;
929 for (i = 0; i < slots; i++)
930 __clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
931
932 /* Let's check and deallocate this dentry page */
933 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
934 NR_DENTRY_IN_BLOCK,
935 0);
936 set_page_dirty(page);
937
938 if (bit_pos == NR_DENTRY_IN_BLOCK &&
939 !f2fs_truncate_hole(dir, page->index, page->index + 1)) {
940 f2fs_clear_page_cache_dirty_tag(page);
941 clear_page_dirty_for_io(page);
942 ClearPageUptodate(page);
943
944 clear_page_private_gcing(page);
945
946 inode_dec_dirty_pages(dir);
947 f2fs_remove_dirty_inode(dir);
948
949 detach_page_private(page);
950 set_page_private(page, 0);
951 }
952 f2fs_put_page(page, 1);
953
954 dir->i_ctime = dir->i_mtime = current_time(dir);
955 f2fs_mark_inode_dirty_sync(dir, false);
956
957 if (inode)
958 f2fs_drop_nlink(dir, inode);
959}
960
961bool f2fs_empty_dir(struct inode *dir)
962{
963 unsigned long bidx = 0;
964 struct page *dentry_page;
965 unsigned int bit_pos;
966 struct f2fs_dentry_block *dentry_blk;
967 unsigned long nblock = dir_blocks(dir);
968
969 if (f2fs_has_inline_dentry(dir))
970 return f2fs_empty_inline_dir(dir);
971
972 while (bidx < nblock) {
973 pgoff_t next_pgofs;
974
975 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
976 if (IS_ERR(dentry_page)) {
977 if (PTR_ERR(dentry_page) == -ENOENT) {
978 bidx = next_pgofs;
979 continue;
980 } else {
981 return false;
982 }
983 }
984
985 dentry_blk = page_address(dentry_page);
986 if (bidx == 0)
987 bit_pos = 2;
988 else
989 bit_pos = 0;
990 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
991 NR_DENTRY_IN_BLOCK,
992 bit_pos);
993
994 f2fs_put_page(dentry_page, 0);
995
996 if (bit_pos < NR_DENTRY_IN_BLOCK)
997 return false;
998
999 bidx++;
1000 }
1001 return true;
1002}
1003
1004int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
1005 unsigned int start_pos, struct fscrypt_str *fstr)
1006{
1007 unsigned char d_type = DT_UNKNOWN;
1008 unsigned int bit_pos;
1009 struct f2fs_dir_entry *de = NULL;
1010 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
1011 struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
1012 struct blk_plug plug;
1013 bool readdir_ra = sbi->readdir_ra;
1014 bool found_valid_dirent = false;
1015 int err = 0;
1016
1017 bit_pos = ((unsigned long)ctx->pos % d->max);
1018
1019 if (readdir_ra)
1020 blk_start_plug(&plug);
1021
1022 while (bit_pos < d->max) {
1023 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
1024 if (bit_pos >= d->max)
1025 break;
1026
1027 de = &d->dentry[bit_pos];
1028 if (de->name_len == 0) {
1029 if (found_valid_dirent || !bit_pos) {
1030 printk_ratelimited(
1031 "%sF2FS-fs (%s): invalid namelen(0), ino:%u, run fsck to fix.",
1032 KERN_WARNING, sbi->sb->s_id,
1033 le32_to_cpu(de->ino));
1034 set_sbi_flag(sbi, SBI_NEED_FSCK);
1035 }
1036 bit_pos++;
1037 ctx->pos = start_pos + bit_pos;
1038 continue;
1039 }
1040
1041 d_type = f2fs_get_de_type(de);
1042
1043 de_name.name = d->filename[bit_pos];
1044 de_name.len = le16_to_cpu(de->name_len);
1045
1046 /* check memory boundary before moving forward */
1047 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
1048 if (unlikely(bit_pos > d->max ||
1049 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
1050 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
1051 __func__, le16_to_cpu(de->name_len));
1052 set_sbi_flag(sbi, SBI_NEED_FSCK);
1053 err = -EFSCORRUPTED;
1054 f2fs_handle_error(sbi, ERROR_CORRUPTED_DIRENT);
1055 goto out;
1056 }
1057
1058 if (IS_ENCRYPTED(d->inode)) {
1059 int save_len = fstr->len;
1060
1061 err = fscrypt_fname_disk_to_usr(d->inode,
1062 (u32)le32_to_cpu(de->hash_code),
1063 0, &de_name, fstr);
1064 if (err)
1065 goto out;
1066
1067 de_name = *fstr;
1068 fstr->len = save_len;
1069 }
1070
1071 if (!dir_emit(ctx, de_name.name, de_name.len,
1072 le32_to_cpu(de->ino), d_type)) {
1073 err = 1;
1074 goto out;
1075 }
1076
1077 if (readdir_ra)
1078 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
1079
1080 ctx->pos = start_pos + bit_pos;
1081 found_valid_dirent = true;
1082 }
1083out:
1084 if (readdir_ra)
1085 blk_finish_plug(&plug);
1086 return err;
1087}
1088
1089static int f2fs_readdir(struct file *file, struct dir_context *ctx)
1090{
1091 struct inode *inode = file_inode(file);
1092 unsigned long npages = dir_blocks(inode);
1093 struct f2fs_dentry_block *dentry_blk = NULL;
1094 struct page *dentry_page = NULL;
1095 struct file_ra_state *ra = &file->f_ra;
1096 loff_t start_pos = ctx->pos;
1097 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
1098 struct f2fs_dentry_ptr d;
1099 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
1100 int err = 0;
1101
1102 if (IS_ENCRYPTED(inode)) {
1103 err = fscrypt_prepare_readdir(inode);
1104 if (err)
1105 goto out;
1106
1107 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);
1108 if (err < 0)
1109 goto out;
1110 }
1111
1112 if (f2fs_has_inline_dentry(inode)) {
1113 err = f2fs_read_inline_dir(file, ctx, &fstr);
1114 goto out_free;
1115 }
1116
1117 for (; n < npages; ctx->pos = n * NR_DENTRY_IN_BLOCK) {
1118 pgoff_t next_pgofs;
1119
1120 /* allow readdir() to be interrupted */
1121 if (fatal_signal_pending(current)) {
1122 err = -ERESTARTSYS;
1123 goto out_free;
1124 }
1125 cond_resched();
1126
1127 /* readahead for multi pages of dir */
1128 if (npages - n > 1 && !ra_has_index(ra, n))
1129 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
1130 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
1131
1132 dentry_page = f2fs_find_data_page(inode, n, &next_pgofs);
1133 if (IS_ERR(dentry_page)) {
1134 err = PTR_ERR(dentry_page);
1135 if (err == -ENOENT) {
1136 err = 0;
1137 n = next_pgofs;
1138 continue;
1139 } else {
1140 goto out_free;
1141 }
1142 }
1143
1144 dentry_blk = page_address(dentry_page);
1145
1146 make_dentry_ptr_block(inode, &d, dentry_blk);
1147
1148 err = f2fs_fill_dentries(ctx, &d,
1149 n * NR_DENTRY_IN_BLOCK, &fstr);
1150 if (err) {
1151 f2fs_put_page(dentry_page, 0);
1152 break;
1153 }
1154
1155 f2fs_put_page(dentry_page, 0);
1156
1157 n++;
1158 }
1159out_free:
1160 fscrypt_fname_free_buffer(&fstr);
1161out:
1162 trace_f2fs_readdir(inode, start_pos, ctx->pos, err);
1163 return err < 0 ? err : 0;
1164}
1165
1166const struct file_operations f2fs_dir_operations = {
1167 .llseek = generic_file_llseek,
1168 .read = generic_read_dir,
1169 .iterate_shared = f2fs_readdir,
1170 .fsync = f2fs_sync_file,
1171 .unlocked_ioctl = f2fs_ioctl,
1172#ifdef CONFIG_COMPAT
1173 .compat_ioctl = f2fs_compat_ioctl,
1174#endif
1175};