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 <linux/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
19static inline bool f2fs_should_fallback_to_linear(struct inode *dir)
20{
21 struct f2fs_sb_info *sbi = F2FS_I_SB(inode: dir);
22
23 switch (F2FS_OPTION(sbi).lookup_mode) {
24 case LOOKUP_PERF:
25 return false;
26 case LOOKUP_COMPAT:
27 return true;
28 case LOOKUP_AUTO:
29 return !sb_no_casefold_compat_fallback(sbi->sb);
30 }
31 return false;
32}
33
34#if IS_ENABLED(CONFIG_UNICODE)
35extern struct kmem_cache *f2fs_cf_name_slab;
36#endif
37
38static unsigned long dir_blocks(struct inode *inode)
39{
40 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
41 >> PAGE_SHIFT;
42}
43
44static unsigned int dir_buckets(unsigned int level, int dir_level)
45{
46 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
47 return BIT(level + dir_level);
48 else
49 return MAX_DIR_BUCKETS;
50}
51
52static unsigned int bucket_blocks(unsigned int level)
53{
54 if (level < MAX_DIR_HASH_DEPTH / 2)
55 return 2;
56 else
57 return 4;
58}
59
60#if IS_ENABLED(CONFIG_UNICODE)
61/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */
62int f2fs_init_casefolded_name(const struct inode *dir,
63 struct f2fs_filename *fname)
64{
65 struct super_block *sb = dir->i_sb;
66 unsigned char *buf;
67 int len;
68
69 if (IS_CASEFOLDED(dir) &&
70 !is_dot_dotdot(name: fname->usr_fname->name, len: fname->usr_fname->len)) {
71 buf = f2fs_kmem_cache_alloc(cachep: f2fs_cf_name_slab,
72 GFP_NOFS, nofail: false, sbi: F2FS_SB(sb));
73 if (!buf)
74 return -ENOMEM;
75
76 len = utf8_casefold(um: sb->s_encoding, str: fname->usr_fname,
77 dest: buf, F2FS_NAME_LEN);
78 if (len <= 0) {
79 kmem_cache_free(s: f2fs_cf_name_slab, objp: buf);
80 if (sb_has_strict_encoding(sb))
81 return -EINVAL;
82 /* fall back to treating name as opaque byte sequence */
83 return 0;
84 }
85 fname->cf_name.name = buf;
86 fname->cf_name.len = len;
87 }
88
89 return 0;
90}
91
92void f2fs_free_casefolded_name(struct f2fs_filename *fname)
93{
94 unsigned char *buf = (unsigned char *)fname->cf_name.name;
95
96 if (buf) {
97 kmem_cache_free(s: f2fs_cf_name_slab, objp: buf);
98 fname->cf_name.name = NULL;
99 }
100}
101#endif /* CONFIG_UNICODE */
102
103static int __f2fs_setup_filename(const struct inode *dir,
104 const struct fscrypt_name *crypt_name,
105 struct f2fs_filename *fname)
106{
107 int err;
108
109 memset(fname, 0, sizeof(*fname));
110
111 fname->usr_fname = crypt_name->usr_fname;
112 fname->disk_name = crypt_name->disk_name;
113#ifdef CONFIG_FS_ENCRYPTION
114 fname->crypto_buf = crypt_name->crypto_buf;
115#endif
116 if (crypt_name->is_nokey_name) {
117 /* hash was decoded from the no-key name */
118 fname->hash = cpu_to_le32(crypt_name->hash);
119 } else {
120 err = f2fs_init_casefolded_name(dir, fname);
121 if (err) {
122 f2fs_free_filename(fname);
123 return err;
124 }
125 f2fs_hash_filename(dir, fname);
126 }
127 return 0;
128}
129
130/*
131 * Prepare to search for @iname in @dir. This is similar to
132 * fscrypt_setup_filename(), but this also handles computing the casefolded name
133 * and the f2fs dirhash if needed, then packing all the information about this
134 * filename up into a 'struct f2fs_filename'.
135 */
136int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
137 int lookup, struct f2fs_filename *fname)
138{
139 struct fscrypt_name crypt_name;
140 int err;
141
142 err = fscrypt_setup_filename(inode: dir, iname, lookup, fname: &crypt_name);
143 if (err)
144 return err;
145
146 return __f2fs_setup_filename(dir, crypt_name: &crypt_name, fname);
147}
148
149/*
150 * Prepare to look up @dentry in @dir. This is similar to
151 * fscrypt_prepare_lookup(), but this also handles computing the casefolded name
152 * and the f2fs dirhash if needed, then packing all the information about this
153 * filename up into a 'struct f2fs_filename'.
154 */
155int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,
156 struct f2fs_filename *fname)
157{
158 struct fscrypt_name crypt_name;
159 int err;
160
161 err = fscrypt_prepare_lookup(dir, dentry, fname: &crypt_name);
162 if (err)
163 return err;
164
165 return __f2fs_setup_filename(dir, crypt_name: &crypt_name, fname);
166}
167
168void f2fs_free_filename(struct f2fs_filename *fname)
169{
170#ifdef CONFIG_FS_ENCRYPTION
171 kfree(objp: fname->crypto_buf.name);
172 fname->crypto_buf.name = NULL;
173#endif
174 f2fs_free_casefolded_name(fname);
175}
176
177static unsigned long dir_block_index(unsigned int level,
178 int dir_level, unsigned int idx)
179{
180 unsigned long i;
181 unsigned long bidx = 0;
182
183 for (i = 0; i < level; i++)
184 bidx += mul_u32_u32(a: dir_buckets(level: i, dir_level),
185 b: bucket_blocks(level: i));
186 bidx += idx * bucket_blocks(level);
187 return bidx;
188}
189
190static struct f2fs_dir_entry *find_in_block(struct inode *dir,
191 struct folio *dentry_folio,
192 const struct f2fs_filename *fname,
193 int *max_slots,
194 bool use_hash)
195{
196 struct f2fs_dentry_block *dentry_blk;
197 struct f2fs_dentry_ptr d;
198
199 dentry_blk = folio_address(folio: dentry_folio);
200
201 make_dentry_ptr_block(inode: dir, d: &d, t: dentry_blk);
202 return f2fs_find_target_dentry(d: &d, fname, max_slots, use_hash);
203}
204
205static inline int f2fs_match_name(const struct inode *dir,
206 const struct f2fs_filename *fname,
207 const u8 *de_name, u32 de_name_len)
208{
209 struct fscrypt_name f;
210
211#if IS_ENABLED(CONFIG_UNICODE)
212 if (fname->cf_name.name)
213 return generic_ci_match(parent: dir, name: fname->usr_fname,
214 folded_name: &fname->cf_name,
215 de_name, de_name_len);
216
217#endif
218 f.usr_fname = fname->usr_fname;
219 f.disk_name = fname->disk_name;
220#ifdef CONFIG_FS_ENCRYPTION
221 f.crypto_buf = fname->crypto_buf;
222#endif
223 return fscrypt_match_name(fname: &f, de_name, de_name_len);
224}
225
226struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
227 const struct f2fs_filename *fname, int *max_slots,
228 bool use_hash)
229{
230 struct f2fs_dir_entry *de;
231 unsigned long bit_pos = 0;
232 int max_len = 0;
233 int res = 0;
234
235 if (max_slots)
236 *max_slots = 0;
237 while (bit_pos < d->max) {
238 if (!test_bit_le(nr: bit_pos, addr: d->bitmap)) {
239 bit_pos++;
240 max_len++;
241 continue;
242 }
243
244 de = &d->dentry[bit_pos];
245
246 if (unlikely(!de->name_len)) {
247 bit_pos++;
248 continue;
249 }
250
251 if (!use_hash || de->hash_code == fname->hash) {
252 res = f2fs_match_name(dir: d->inode, fname,
253 de_name: d->filename[bit_pos],
254 le16_to_cpu(de->name_len));
255 if (res < 0)
256 return ERR_PTR(error: res);
257 if (res)
258 goto found;
259 }
260
261 if (max_slots && max_len > *max_slots)
262 *max_slots = max_len;
263 max_len = 0;
264
265 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
266 }
267
268 de = NULL;
269found:
270 if (max_slots && max_len > *max_slots)
271 *max_slots = max_len;
272 return de;
273}
274
275static struct f2fs_dir_entry *find_in_level(struct inode *dir,
276 unsigned int level,
277 const struct f2fs_filename *fname,
278 struct folio **res_folio,
279 bool use_hash)
280{
281 int s = GET_DENTRY_SLOTS(fname->disk_name.len);
282 unsigned int nbucket, nblock;
283 unsigned int bidx, end_block, bucket_no;
284 struct f2fs_dir_entry *de = NULL;
285 pgoff_t next_pgofs;
286 bool room = false;
287 int max_slots;
288
289 nbucket = dir_buckets(level, dir_level: F2FS_I(inode: dir)->i_dir_level);
290 nblock = bucket_blocks(level);
291
292 bucket_no = use_hash ? le32_to_cpu(fname->hash) % nbucket : 0;
293
294start_find_bucket:
295 bidx = dir_block_index(level, dir_level: F2FS_I(inode: dir)->i_dir_level,
296 idx: bucket_no);
297 end_block = bidx + nblock;
298
299 while (bidx < end_block) {
300 /* no need to allocate new dentry pages to all the indices */
301 struct folio *dentry_folio;
302 dentry_folio = f2fs_find_data_folio(inode: dir, index: bidx, next_pgofs: &next_pgofs);
303 if (IS_ERR(ptr: dentry_folio)) {
304 if (PTR_ERR(ptr: dentry_folio) == -ENOENT) {
305 room = true;
306 bidx = next_pgofs;
307 continue;
308 } else {
309 *res_folio = dentry_folio;
310 break;
311 }
312 }
313
314 de = find_in_block(dir, dentry_folio, fname, max_slots: &max_slots, use_hash);
315 if (IS_ERR(ptr: de)) {
316 *res_folio = ERR_CAST(ptr: de);
317 de = NULL;
318 break;
319 } else if (de) {
320 *res_folio = dentry_folio;
321 break;
322 }
323
324 if (max_slots >= s)
325 room = true;
326 f2fs_folio_put(folio: dentry_folio, unlock: false);
327
328 bidx++;
329 }
330
331 if (de)
332 return de;
333
334 if (likely(use_hash)) {
335 if (room && F2FS_I(inode: dir)->chash != fname->hash) {
336 F2FS_I(inode: dir)->chash = fname->hash;
337 F2FS_I(inode: dir)->clevel = level;
338 }
339 } else if (++bucket_no < nbucket) {
340 goto start_find_bucket;
341 }
342 return NULL;
343}
344
345struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
346 const struct f2fs_filename *fname,
347 struct folio **res_folio)
348{
349 unsigned long npages = dir_blocks(inode: dir);
350 struct f2fs_dir_entry *de = NULL;
351 unsigned int max_depth;
352 unsigned int level;
353 bool use_hash = true;
354
355 *res_folio = NULL;
356
357#if IS_ENABLED(CONFIG_UNICODE)
358start_find_entry:
359#endif
360 if (f2fs_has_inline_dentry(inode: dir)) {
361 de = f2fs_find_in_inline_dir(dir, fname, res_folio, use_hash);
362 goto out;
363 }
364
365 if (npages == 0)
366 goto out;
367
368 max_depth = F2FS_I(inode: dir)->i_current_depth;
369 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
370 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
371 dir->i_ino, max_depth);
372 max_depth = MAX_DIR_HASH_DEPTH;
373 f2fs_i_depth_write(inode: dir, depth: max_depth);
374 }
375
376 for (level = 0; level < max_depth; level++) {
377 de = find_in_level(dir, level, fname, res_folio, use_hash);
378 if (de || IS_ERR(ptr: *res_folio))
379 break;
380 }
381
382out:
383#if IS_ENABLED(CONFIG_UNICODE)
384 if (f2fs_should_fallback_to_linear(dir) &&
385 IS_CASEFOLDED(dir) && !de && use_hash) {
386 use_hash = false;
387 goto start_find_entry;
388 }
389#endif
390 /* This is to increase the speed of f2fs_create */
391 if (!de)
392 F2FS_I(inode: dir)->task = current;
393 return de;
394}
395
396/*
397 * Find an entry in the specified directory with the wanted name.
398 * It returns the page where the entry was found (as a parameter - res_page),
399 * and the entry itself. Page is returned mapped and unlocked.
400 * Entry is guaranteed to be valid.
401 */
402struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
403 const struct qstr *child, struct folio **res_folio)
404{
405 struct f2fs_dir_entry *de = NULL;
406 struct f2fs_filename fname;
407 int err;
408
409 err = f2fs_setup_filename(dir, iname: child, lookup: 1, fname: &fname);
410 if (err) {
411 if (err == -ENOENT)
412 *res_folio = NULL;
413 else
414 *res_folio = ERR_PTR(error: err);
415 return NULL;
416 }
417
418 de = __f2fs_find_entry(dir, fname: &fname, res_folio);
419
420 f2fs_free_filename(fname: &fname);
421 return de;
422}
423
424struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct folio **f)
425{
426 return f2fs_find_entry(dir, child: &dotdot_name, res_folio: f);
427}
428
429ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
430 struct folio **folio)
431{
432 ino_t res = 0;
433 struct f2fs_dir_entry *de;
434
435 de = f2fs_find_entry(dir, child: qstr, res_folio: folio);
436 if (de) {
437 res = le32_to_cpu(de->ino);
438 f2fs_folio_put(folio: *folio, unlock: false);
439 }
440
441 return res;
442}
443
444void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
445 struct folio *folio, struct inode *inode)
446{
447 enum page_type type = f2fs_has_inline_dentry(inode: dir) ? NODE : DATA;
448
449 folio_lock(folio);
450 f2fs_folio_wait_writeback(folio, type, ordered: true, locked: true);
451 de->ino = cpu_to_le32(inode->i_ino);
452 de->file_type = fs_umode_to_ftype(mode: inode->i_mode);
453 folio_mark_dirty(folio);
454
455 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
456 f2fs_mark_inode_dirty_sync(inode: dir, sync: false);
457 f2fs_folio_put(folio, unlock: true);
458}
459
460static void init_dent_inode(struct inode *dir, struct inode *inode,
461 const struct f2fs_filename *fname,
462 struct folio *ifolio)
463{
464 struct f2fs_inode *ri;
465
466 if (!fname) /* tmpfile case? */
467 return;
468
469 f2fs_folio_wait_writeback(folio: ifolio, type: NODE, ordered: true, locked: true);
470
471 /* copy name info. to this inode folio */
472 ri = F2FS_INODE(folio: ifolio);
473 ri->i_namelen = cpu_to_le32(fname->disk_name.len);
474 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
475 if (IS_ENCRYPTED(dir)) {
476 file_set_enc_name(inode);
477 /*
478 * Roll-forward recovery doesn't have encryption keys available,
479 * so it can't compute the dirhash for encrypted+casefolded
480 * filenames. Append it to i_name if possible. Else, disable
481 * roll-forward recovery of the dentry (i.e., make fsync'ing the
482 * file force a checkpoint) by setting LOST_PINO.
483 */
484 if (IS_CASEFOLDED(dir)) {
485 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
486 F2FS_NAME_LEN)
487 put_unaligned(fname->hash, (f2fs_hash_t *)
488 &ri->i_name[fname->disk_name.len]);
489 else
490 file_lost_pino(inode);
491 }
492 }
493 folio_mark_dirty(folio: ifolio);
494}
495
496void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
497 struct f2fs_dentry_ptr *d)
498{
499 struct fscrypt_str dot = FSTR_INIT(".", 1);
500 struct fscrypt_str dotdot = FSTR_INIT("..", 2);
501
502 /* update dirent of "." */
503 f2fs_update_dentry(ino: inode->i_ino, mode: inode->i_mode, d, name: &dot, name_hash: 0, bit_pos: 0);
504
505 /* update dirent of ".." */
506 f2fs_update_dentry(ino: parent->i_ino, mode: parent->i_mode, d, name: &dotdot, name_hash: 0, bit_pos: 1);
507}
508
509static int make_empty_dir(struct inode *inode,
510 struct inode *parent, struct folio *folio)
511{
512 struct folio *dentry_folio;
513 struct f2fs_dentry_block *dentry_blk;
514 struct f2fs_dentry_ptr d;
515
516 if (f2fs_has_inline_dentry(inode))
517 return f2fs_make_empty_inline_dir(inode, parent, ifolio: folio);
518
519 dentry_folio = f2fs_get_new_data_folio(inode, ifolio: folio, index: 0, new_i_size: true);
520 if (IS_ERR(ptr: dentry_folio))
521 return PTR_ERR(ptr: dentry_folio);
522
523 dentry_blk = folio_address(folio: dentry_folio);
524
525 make_dentry_ptr_block(NULL, d: &d, t: dentry_blk);
526 f2fs_do_make_empty_dir(inode, parent, d: &d);
527
528 folio_mark_dirty(folio: dentry_folio);
529 f2fs_folio_put(folio: dentry_folio, unlock: true);
530 return 0;
531}
532
533struct folio *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
534 const struct f2fs_filename *fname, struct folio *dfolio)
535{
536 struct folio *folio;
537 int err;
538
539 if (is_inode_flag_set(inode, flag: FI_NEW_INODE)) {
540 folio = f2fs_new_inode_folio(inode);
541 if (IS_ERR(ptr: folio))
542 return folio;
543
544 if (S_ISDIR(inode->i_mode)) {
545 /* in order to handle error case */
546 folio_get(folio);
547 err = make_empty_dir(inode, parent: dir, folio);
548 if (err) {
549 folio_lock(folio);
550 goto put_error;
551 }
552 folio_put(folio);
553 }
554
555 err = f2fs_init_acl(inode, dir, ifolio: folio, dfolio);
556 if (err)
557 goto put_error;
558
559 err = f2fs_init_security(inode, dir,
560 fname ? fname->usr_fname : NULL,
561 folio);
562 if (err)
563 goto put_error;
564
565 if (IS_ENCRYPTED(inode)) {
566 err = fscrypt_set_context(inode, fs_data: folio);
567 if (err)
568 goto put_error;
569 }
570 } else {
571 folio = f2fs_get_inode_folio(sbi: F2FS_I_SB(inode: dir), ino: inode->i_ino);
572 if (IS_ERR(ptr: folio))
573 return folio;
574 }
575
576 init_dent_inode(dir, inode, fname, ifolio: folio);
577
578 /*
579 * This file should be checkpointed during fsync.
580 * We lost i_pino from now on.
581 */
582 if (is_inode_flag_set(inode, flag: FI_INC_LINK)) {
583 if (!S_ISDIR(inode->i_mode))
584 file_lost_pino(inode);
585 /*
586 * If link the tmpfile to alias through linkat path,
587 * we should remove this inode from orphan list.
588 */
589 if (inode->i_nlink == 0)
590 f2fs_remove_orphan_inode(sbi: F2FS_I_SB(inode: dir), ino: inode->i_ino);
591 f2fs_i_links_write(inode, inc: true);
592 }
593 return folio;
594
595put_error:
596 clear_nlink(inode);
597 f2fs_update_inode(inode, node_folio: folio);
598 f2fs_folio_put(folio, unlock: true);
599 return ERR_PTR(error: err);
600}
601
602void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
603 unsigned int current_depth)
604{
605 if (inode && is_inode_flag_set(inode, flag: FI_NEW_INODE)) {
606 if (S_ISDIR(inode->i_mode))
607 f2fs_i_links_write(inode: dir, inc: true);
608 clear_inode_flag(inode, flag: FI_NEW_INODE);
609 }
610 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
611 f2fs_mark_inode_dirty_sync(inode: dir, sync: false);
612
613 if (F2FS_I(inode: dir)->i_current_depth != current_depth)
614 f2fs_i_depth_write(inode: dir, depth: current_depth);
615
616 if (inode && is_inode_flag_set(inode, flag: FI_INC_LINK))
617 clear_inode_flag(inode, flag: FI_INC_LINK);
618}
619
620int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
621{
622 int bit_start = 0;
623 int zero_start, zero_end;
624next:
625 zero_start = find_next_zero_bit_le(addr: bitmap, size: max_slots, offset: bit_start);
626 if (zero_start >= max_slots)
627 return max_slots;
628
629 zero_end = find_next_bit_le(addr: bitmap, size: max_slots, offset: zero_start);
630 if (zero_end - zero_start >= slots)
631 return zero_start;
632
633 bit_start = zero_end + 1;
634
635 if (zero_end + 1 >= max_slots)
636 return max_slots;
637 goto next;
638}
639
640bool f2fs_has_enough_room(struct inode *dir, struct folio *ifolio,
641 const struct f2fs_filename *fname)
642{
643 struct f2fs_dentry_ptr d;
644 unsigned int bit_pos;
645 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
646
647 make_dentry_ptr_inline(inode: dir, d: &d, t: inline_data_addr(inode: dir, folio: ifolio));
648
649 bit_pos = f2fs_room_for_filename(bitmap: d.bitmap, slots, max_slots: d.max);
650
651 return bit_pos < d.max;
652}
653
654void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
655 const struct fscrypt_str *name, f2fs_hash_t name_hash,
656 unsigned int bit_pos)
657{
658 struct f2fs_dir_entry *de;
659 int slots = GET_DENTRY_SLOTS(name->len);
660 int i;
661
662 de = &d->dentry[bit_pos];
663 de->hash_code = name_hash;
664 de->name_len = cpu_to_le16(name->len);
665 memcpy(d->filename[bit_pos], name->name, name->len);
666 de->ino = cpu_to_le32(ino);
667 de->file_type = fs_umode_to_ftype(mode);
668 for (i = 0; i < slots; i++) {
669 __set_bit_le(nr: bit_pos + i, addr: (void *)d->bitmap);
670 /* avoid wrong garbage data for readdir */
671 if (i)
672 (de + i)->name_len = 0;
673 }
674}
675
676int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
677 struct inode *inode, nid_t ino, umode_t mode)
678{
679 unsigned int bit_pos;
680 unsigned int level;
681 unsigned int current_depth;
682 unsigned long bidx, block;
683 unsigned int nbucket, nblock;
684 struct folio *dentry_folio = NULL;
685 struct f2fs_dentry_block *dentry_blk = NULL;
686 struct f2fs_dentry_ptr d;
687 struct folio *folio = NULL;
688 int slots, err = 0;
689
690 level = 0;
691 slots = GET_DENTRY_SLOTS(fname->disk_name.len);
692
693 current_depth = F2FS_I(inode: dir)->i_current_depth;
694 if (F2FS_I(inode: dir)->chash == fname->hash) {
695 level = F2FS_I(inode: dir)->clevel;
696 F2FS_I(inode: dir)->chash = 0;
697 }
698
699start:
700 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))
701 return -ENOSPC;
702
703 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
704 return -ENOSPC;
705
706 /* Increase the depth, if required */
707 if (level == current_depth)
708 ++current_depth;
709
710 nbucket = dir_buckets(level, dir_level: F2FS_I(inode: dir)->i_dir_level);
711 nblock = bucket_blocks(level);
712
713 bidx = dir_block_index(level, dir_level: F2FS_I(inode: dir)->i_dir_level,
714 idx: (le32_to_cpu(fname->hash) % nbucket));
715
716 for (block = bidx; block <= (bidx + nblock - 1); block++) {
717 dentry_folio = f2fs_get_new_data_folio(inode: dir, NULL, index: block, new_i_size: true);
718 if (IS_ERR(ptr: dentry_folio))
719 return PTR_ERR(ptr: dentry_folio);
720
721 dentry_blk = folio_address(folio: dentry_folio);
722 bit_pos = f2fs_room_for_filename(bitmap: &dentry_blk->dentry_bitmap,
723 slots, NR_DENTRY_IN_BLOCK);
724 if (bit_pos < NR_DENTRY_IN_BLOCK)
725 goto add_dentry;
726
727 f2fs_folio_put(folio: dentry_folio, unlock: true);
728 }
729
730 /* Move to next level to find the empty slot for new dentry */
731 ++level;
732 goto start;
733add_dentry:
734 f2fs_folio_wait_writeback(folio: dentry_folio, type: DATA, ordered: true, locked: true);
735
736 if (inode) {
737 f2fs_down_write(sem: &F2FS_I(inode)->i_sem);
738 folio = f2fs_init_inode_metadata(inode, dir, fname, NULL);
739 if (IS_ERR(ptr: folio)) {
740 err = PTR_ERR(ptr: folio);
741 goto fail;
742 }
743 }
744
745 make_dentry_ptr_block(NULL, d: &d, t: dentry_blk);
746 f2fs_update_dentry(ino, mode, d: &d, name: &fname->disk_name, name_hash: fname->hash,
747 bit_pos);
748
749 folio_mark_dirty(folio: dentry_folio);
750
751 if (inode) {
752 f2fs_i_pino_write(inode, pino: dir->i_ino);
753
754 /* synchronize inode page's data from inode cache */
755 if (is_inode_flag_set(inode, flag: FI_NEW_INODE))
756 f2fs_update_inode(inode, node_folio: folio);
757
758 f2fs_folio_put(folio, unlock: true);
759 }
760
761 f2fs_update_parent_metadata(dir, inode, current_depth);
762fail:
763 if (inode)
764 f2fs_up_write(sem: &F2FS_I(inode)->i_sem);
765
766 f2fs_folio_put(folio: dentry_folio, unlock: true);
767
768 return err;
769}
770
771int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
772 struct inode *inode, nid_t ino, umode_t mode)
773{
774 int err = -EAGAIN;
775
776 if (f2fs_has_inline_dentry(inode: dir)) {
777 /*
778 * Should get i_xattr_sem to keep the lock order:
779 * i_xattr_sem -> inode_page lock used by f2fs_setxattr.
780 */
781 f2fs_down_read(sem: &F2FS_I(inode: dir)->i_xattr_sem);
782 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
783 f2fs_up_read(sem: &F2FS_I(inode: dir)->i_xattr_sem);
784 }
785 if (err == -EAGAIN)
786 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
787
788 f2fs_update_time(sbi: F2FS_I_SB(inode: dir), type: REQ_TIME);
789 return err;
790}
791
792/*
793 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
794 * f2fs_unlock_op().
795 */
796int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
797 struct inode *inode, nid_t ino, umode_t mode)
798{
799 struct f2fs_filename fname;
800 struct folio *folio = NULL;
801 struct f2fs_dir_entry *de = NULL;
802 int err;
803
804 err = f2fs_setup_filename(dir, iname: name, lookup: 0, fname: &fname);
805 if (err)
806 return err;
807
808 /*
809 * An immature stackable filesystem shows a race condition between lookup
810 * and create. If we have same task when doing lookup and create, it's
811 * definitely fine as expected by VFS normally. Otherwise, let's just
812 * verify on-disk dentry one more time, which guarantees filesystem
813 * consistency more.
814 */
815 if (current != F2FS_I(inode: dir)->task) {
816 de = __f2fs_find_entry(dir, fname: &fname, res_folio: &folio);
817 F2FS_I(inode: dir)->task = NULL;
818 }
819 if (de) {
820 f2fs_folio_put(folio, unlock: false);
821 err = -EEXIST;
822 } else if (IS_ERR(ptr: folio)) {
823 err = PTR_ERR(ptr: folio);
824 } else {
825 err = f2fs_add_dentry(dir, fname: &fname, inode, ino, mode);
826 }
827 f2fs_free_filename(fname: &fname);
828 return err;
829}
830
831int f2fs_do_tmpfile(struct inode *inode, struct inode *dir,
832 struct f2fs_filename *fname)
833{
834 struct folio *folio;
835 int err = 0;
836
837 f2fs_down_write(sem: &F2FS_I(inode)->i_sem);
838 folio = f2fs_init_inode_metadata(inode, dir, fname, NULL);
839 if (IS_ERR(ptr: folio)) {
840 err = PTR_ERR(ptr: folio);
841 goto fail;
842 }
843 f2fs_folio_put(folio, unlock: true);
844
845 clear_inode_flag(inode, flag: FI_NEW_INODE);
846 f2fs_update_time(sbi: F2FS_I_SB(inode), type: REQ_TIME);
847fail:
848 f2fs_up_write(sem: &F2FS_I(inode)->i_sem);
849 return err;
850}
851
852void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
853{
854 struct f2fs_sb_info *sbi = F2FS_I_SB(inode: dir);
855
856 f2fs_down_write(sem: &F2FS_I(inode)->i_sem);
857
858 if (S_ISDIR(inode->i_mode))
859 f2fs_i_links_write(inode: dir, inc: false);
860 inode_set_ctime_current(inode);
861
862 f2fs_i_links_write(inode, inc: false);
863 if (S_ISDIR(inode->i_mode)) {
864 f2fs_i_links_write(inode, inc: false);
865 f2fs_i_size_write(inode, i_size: 0);
866 }
867 f2fs_up_write(sem: &F2FS_I(inode)->i_sem);
868
869 if (inode->i_nlink == 0)
870 f2fs_add_orphan_inode(inode);
871 else
872 f2fs_release_orphan_inode(sbi);
873}
874
875/*
876 * It only removes the dentry from the dentry page, corresponding name
877 * entry in name page does not need to be touched during deletion.
878 */
879void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct folio *folio,
880 struct inode *dir, struct inode *inode)
881{
882 struct f2fs_dentry_block *dentry_blk;
883 unsigned int bit_pos;
884 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
885 pgoff_t index = folio->index;
886 int i;
887
888 f2fs_update_time(sbi: F2FS_I_SB(inode: dir), type: REQ_TIME);
889
890 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
891 f2fs_add_ino_entry(sbi: F2FS_I_SB(inode: dir), ino: dir->i_ino, type: TRANS_DIR_INO);
892
893 if (f2fs_has_inline_dentry(inode: dir))
894 return f2fs_delete_inline_entry(dentry, folio, dir, inode);
895
896 folio_lock(folio);
897 f2fs_folio_wait_writeback(folio, type: DATA, ordered: true, locked: true);
898
899 dentry_blk = folio_address(folio);
900 bit_pos = dentry - dentry_blk->dentry;
901 for (i = 0; i < slots; i++)
902 __clear_bit_le(nr: bit_pos + i, addr: &dentry_blk->dentry_bitmap);
903
904 /* Let's check and deallocate this dentry page */
905 bit_pos = find_next_bit_le(addr: &dentry_blk->dentry_bitmap,
906 NR_DENTRY_IN_BLOCK,
907 offset: 0);
908 folio_mark_dirty(folio);
909
910 if (bit_pos == NR_DENTRY_IN_BLOCK &&
911 !f2fs_truncate_hole(inode: dir, pg_start: index, pg_end: index + 1)) {
912 f2fs_clear_page_cache_dirty_tag(folio);
913 folio_clear_dirty_for_io(folio);
914 folio_clear_uptodate(folio);
915 folio_detach_private(folio);
916
917 inode_dec_dirty_pages(inode: dir);
918 f2fs_remove_dirty_inode(inode: dir);
919 }
920 f2fs_folio_put(folio, unlock: true);
921
922 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
923 f2fs_mark_inode_dirty_sync(inode: dir, sync: false);
924
925 if (inode)
926 f2fs_drop_nlink(dir, inode);
927}
928
929bool f2fs_empty_dir(struct inode *dir)
930{
931 unsigned long bidx = 0;
932 unsigned int bit_pos;
933 struct f2fs_dentry_block *dentry_blk;
934 unsigned long nblock = dir_blocks(inode: dir);
935
936 if (f2fs_has_inline_dentry(inode: dir))
937 return f2fs_empty_inline_dir(dir);
938
939 while (bidx < nblock) {
940 pgoff_t next_pgofs;
941 struct folio *dentry_folio;
942
943 dentry_folio = f2fs_find_data_folio(inode: dir, index: bidx, next_pgofs: &next_pgofs);
944 if (IS_ERR(ptr: dentry_folio)) {
945 if (PTR_ERR(ptr: dentry_folio) == -ENOENT) {
946 bidx = next_pgofs;
947 continue;
948 } else {
949 return false;
950 }
951 }
952
953 dentry_blk = folio_address(folio: dentry_folio);
954 if (bidx == 0)
955 bit_pos = 2;
956 else
957 bit_pos = 0;
958 bit_pos = find_next_bit_le(addr: &dentry_blk->dentry_bitmap,
959 NR_DENTRY_IN_BLOCK,
960 offset: bit_pos);
961
962 f2fs_folio_put(folio: dentry_folio, unlock: false);
963
964 if (bit_pos < NR_DENTRY_IN_BLOCK)
965 return false;
966
967 bidx++;
968 }
969 return true;
970}
971
972int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
973 unsigned int start_pos, struct fscrypt_str *fstr)
974{
975 unsigned char d_type = DT_UNKNOWN;
976 unsigned int bit_pos;
977 struct f2fs_dir_entry *de = NULL;
978 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
979 struct f2fs_sb_info *sbi = F2FS_I_SB(inode: d->inode);
980 struct blk_plug plug;
981 bool readdir_ra = sbi->readdir_ra;
982 bool found_valid_dirent = false;
983 int err = 0;
984
985 bit_pos = ((unsigned long)ctx->pos % d->max);
986
987 if (readdir_ra)
988 blk_start_plug(&plug);
989
990 while (bit_pos < d->max) {
991 bit_pos = find_next_bit_le(addr: d->bitmap, size: d->max, offset: bit_pos);
992 if (bit_pos >= d->max)
993 break;
994
995 de = &d->dentry[bit_pos];
996 if (de->name_len == 0) {
997 if (found_valid_dirent || !bit_pos) {
998 f2fs_warn_ratelimited(sbi,
999 "invalid namelen(0), ino:%u, run fsck to fix.",
1000 le32_to_cpu(de->ino));
1001 set_sbi_flag(sbi, type: SBI_NEED_FSCK);
1002 }
1003 bit_pos++;
1004 ctx->pos = start_pos + bit_pos;
1005 continue;
1006 }
1007
1008 d_type = fs_ftype_to_dtype(filetype: de->file_type);
1009
1010 de_name.name = d->filename[bit_pos];
1011 de_name.len = le16_to_cpu(de->name_len);
1012
1013 /* check memory boundary before moving forward */
1014 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
1015 if (unlikely(bit_pos > d->max ||
1016 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
1017 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
1018 __func__, le16_to_cpu(de->name_len));
1019 set_sbi_flag(sbi, type: SBI_NEED_FSCK);
1020 err = -EFSCORRUPTED;
1021 f2fs_handle_error(sbi, error: ERROR_CORRUPTED_DIRENT);
1022 goto out;
1023 }
1024
1025 if (IS_ENCRYPTED(d->inode)) {
1026 int save_len = fstr->len;
1027
1028 err = fscrypt_fname_disk_to_usr(inode: d->inode,
1029 hash: (u32)le32_to_cpu(de->hash_code),
1030 minor_hash: 0, iname: &de_name, oname: fstr);
1031 if (err)
1032 goto out;
1033
1034 de_name = *fstr;
1035 fstr->len = save_len;
1036 }
1037
1038 if (!dir_emit(ctx, name: de_name.name, namelen: de_name.len,
1039 le32_to_cpu(de->ino), type: d_type)) {
1040 err = 1;
1041 goto out;
1042 }
1043
1044 if (readdir_ra)
1045 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
1046
1047 ctx->pos = start_pos + bit_pos;
1048 found_valid_dirent = true;
1049 }
1050out:
1051 if (readdir_ra)
1052 blk_finish_plug(&plug);
1053 return err;
1054}
1055
1056static int f2fs_readdir(struct file *file, struct dir_context *ctx)
1057{
1058 struct inode *inode = file_inode(f: file);
1059 unsigned long npages = dir_blocks(inode);
1060 struct f2fs_dentry_block *dentry_blk = NULL;
1061 struct file_ra_state *ra = &file->f_ra;
1062 loff_t start_pos = ctx->pos;
1063 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
1064 struct f2fs_dentry_ptr d;
1065 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
1066 int err = 0;
1067
1068 if (IS_ENCRYPTED(inode)) {
1069 err = fscrypt_prepare_readdir(dir: inode);
1070 if (err)
1071 goto out;
1072
1073 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, crypto_str: &fstr);
1074 if (err < 0)
1075 goto out;
1076 }
1077
1078 if (f2fs_has_inline_dentry(inode)) {
1079 err = f2fs_read_inline_dir(file, ctx, fstr: &fstr);
1080 goto out_free;
1081 }
1082
1083 for (; n < npages; ctx->pos = n * NR_DENTRY_IN_BLOCK) {
1084 struct folio *dentry_folio;
1085 pgoff_t next_pgofs;
1086
1087 /* allow readdir() to be interrupted */
1088 if (fatal_signal_pending(current)) {
1089 err = -ERESTARTSYS;
1090 goto out_free;
1091 }
1092 cond_resched();
1093
1094 /* readahead for multi pages of dir */
1095 if (npages - n > 1 && !ra_has_index(ra, index: n))
1096 page_cache_sync_readahead(mapping: inode->i_mapping, ra, file, index: n,
1097 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
1098
1099 dentry_folio = f2fs_find_data_folio(inode, index: n, next_pgofs: &next_pgofs);
1100 if (IS_ERR(ptr: dentry_folio)) {
1101 err = PTR_ERR(ptr: dentry_folio);
1102 if (err == -ENOENT) {
1103 err = 0;
1104 n = next_pgofs;
1105 continue;
1106 } else {
1107 goto out_free;
1108 }
1109 }
1110
1111 dentry_blk = folio_address(folio: dentry_folio);
1112
1113 make_dentry_ptr_block(inode, d: &d, t: dentry_blk);
1114
1115 err = f2fs_fill_dentries(ctx, d: &d,
1116 start_pos: n * NR_DENTRY_IN_BLOCK, fstr: &fstr);
1117 f2fs_folio_put(folio: dentry_folio, unlock: false);
1118 if (err)
1119 break;
1120
1121 n++;
1122 }
1123out_free:
1124 fscrypt_fname_free_buffer(crypto_str: &fstr);
1125out:
1126 trace_f2fs_readdir(dir: inode, start_pos, end_pos: ctx->pos, err);
1127 return err < 0 ? err : 0;
1128}
1129
1130const struct file_operations f2fs_dir_operations = {
1131 .llseek = generic_file_llseek,
1132 .read = generic_read_dir,
1133 .iterate_shared = f2fs_readdir,
1134 .fsync = f2fs_sync_file,
1135 .unlocked_ioctl = f2fs_ioctl,
1136#ifdef CONFIG_COMPAT
1137 .compat_ioctl = f2fs_compat_ioctl,
1138#endif
1139};
1140

source code of linux/fs/f2fs/dir.c