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1/*
2 * fs/f2fs/dir.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/fs.h>
12#include <linux/f2fs_fs.h>
13#include "f2fs.h"
14#include "node.h"
15#include "acl.h"
16#include "xattr.h"
17
18static unsigned long dir_blocks(struct inode *inode)
19{
20 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
21 >> PAGE_SHIFT;
22}
23
24static unsigned int dir_buckets(unsigned int level, int dir_level)
25{
26 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
27 return 1 << (level + dir_level);
28 else
29 return MAX_DIR_BUCKETS;
30}
31
32static unsigned int bucket_blocks(unsigned int level)
33{
34 if (level < MAX_DIR_HASH_DEPTH / 2)
35 return 2;
36 else
37 return 4;
38}
39
40unsigned char f2fs_filetype_table[F2FS_FT_MAX] = {
41 [F2FS_FT_UNKNOWN] = DT_UNKNOWN,
42 [F2FS_FT_REG_FILE] = DT_REG,
43 [F2FS_FT_DIR] = DT_DIR,
44 [F2FS_FT_CHRDEV] = DT_CHR,
45 [F2FS_FT_BLKDEV] = DT_BLK,
46 [F2FS_FT_FIFO] = DT_FIFO,
47 [F2FS_FT_SOCK] = DT_SOCK,
48 [F2FS_FT_SYMLINK] = DT_LNK,
49};
50
51#define S_SHIFT 12
52static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
53 [S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE,
54 [S_IFDIR >> S_SHIFT] = F2FS_FT_DIR,
55 [S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV,
56 [S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV,
57 [S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO,
58 [S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK,
59 [S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK,
60};
61
62void set_de_type(struct f2fs_dir_entry *de, umode_t mode)
63{
64 de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
65}
66
67static unsigned long dir_block_index(unsigned int level,
68 int dir_level, unsigned int idx)
69{
70 unsigned long i;
71 unsigned long bidx = 0;
72
73 for (i = 0; i < level; i++)
74 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
75 bidx += idx * bucket_blocks(level);
76 return bidx;
77}
78
79static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
80 struct fscrypt_name *fname,
81 f2fs_hash_t namehash,
82 int *max_slots,
83 struct page **res_page)
84{
85 struct f2fs_dentry_block *dentry_blk;
86 struct f2fs_dir_entry *de;
87 struct f2fs_dentry_ptr d;
88
89 dentry_blk = (struct f2fs_dentry_block *)kmap(dentry_page);
90
91 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
92 de = find_target_dentry(fname, namehash, max_slots, &d);
93 if (de)
94 *res_page = dentry_page;
95 else
96 kunmap(dentry_page);
97
98 /*
99 * For the most part, it should be a bug when name_len is zero.
100 * We stop here for figuring out where the bugs has occurred.
101 */
102 f2fs_bug_on(F2FS_P_SB(dentry_page), d.max < 0);
103 return de;
104}
105
106struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
107 f2fs_hash_t namehash, int *max_slots,
108 struct f2fs_dentry_ptr *d)
109{
110 struct f2fs_dir_entry *de;
111 unsigned long bit_pos = 0;
112 int max_len = 0;
113 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
114 struct fscrypt_str *name = &fname->disk_name;
115
116 if (max_slots)
117 *max_slots = 0;
118 while (bit_pos < d->max) {
119 if (!test_bit_le(bit_pos, d->bitmap)) {
120 bit_pos++;
121 max_len++;
122 continue;
123 }
124
125 de = &d->dentry[bit_pos];
126
127 /* encrypted case */
128 de_name.name = d->filename[bit_pos];
129 de_name.len = le16_to_cpu(de->name_len);
130
131 /* show encrypted name */
132 if (fname->hash) {
133 if (de->hash_code == fname->hash)
134 goto found;
135 } else if (de_name.len == name->len &&
136 de->hash_code == namehash &&
137 !memcmp(de_name.name, name->name, name->len))
138 goto found;
139
140 if (max_slots && max_len > *max_slots)
141 *max_slots = max_len;
142 max_len = 0;
143
144 /* remain bug on condition */
145 if (unlikely(!de->name_len))
146 d->max = -1;
147
148 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
149 }
150
151 de = NULL;
152found:
153 if (max_slots && max_len > *max_slots)
154 *max_slots = max_len;
155 return de;
156}
157
158static struct f2fs_dir_entry *find_in_level(struct inode *dir,
159 unsigned int level,
160 struct fscrypt_name *fname,
161 struct page **res_page)
162{
163 struct qstr name = FSTR_TO_QSTR(&fname->disk_name);
164 int s = GET_DENTRY_SLOTS(name.len);
165 unsigned int nbucket, nblock;
166 unsigned int bidx, end_block;
167 struct page *dentry_page;
168 struct f2fs_dir_entry *de = NULL;
169 bool room = false;
170 int max_slots;
171 f2fs_hash_t namehash;
172
173 namehash = f2fs_dentry_hash(&name);
174
175 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
176 nblock = bucket_blocks(level);
177
178 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
179 le32_to_cpu(namehash) % nbucket);
180 end_block = bidx + nblock;
181
182 for (; bidx < end_block; bidx++) {
183 /* no need to allocate new dentry pages to all the indices */
184 dentry_page = find_data_page(dir, bidx);
185 if (IS_ERR(dentry_page)) {
186 room = true;
187 continue;
188 }
189
190 de = find_in_block(dentry_page, fname, namehash, &max_slots,
191 res_page);
192 if (de)
193 break;
194
195 if (max_slots >= s)
196 room = true;
197 f2fs_put_page(dentry_page, 0);
198 }
199
200 if (!de && room && F2FS_I(dir)->chash != namehash) {
201 F2FS_I(dir)->chash = namehash;
202 F2FS_I(dir)->clevel = level;
203 }
204
205 return de;
206}
207
208/*
209 * Find an entry in the specified directory with the wanted name.
210 * It returns the page where the entry was found (as a parameter - res_page),
211 * and the entry itself. Page is returned mapped and unlocked.
212 * Entry is guaranteed to be valid.
213 */
214struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
215 struct qstr *child, struct page **res_page)
216{
217 unsigned long npages = dir_blocks(dir);
218 struct f2fs_dir_entry *de = NULL;
219 unsigned int max_depth;
220 unsigned int level;
221 struct fscrypt_name fname;
222 int err;
223
224 *res_page = NULL;
225
226 err = fscrypt_setup_filename(dir, child, 1, &fname);
227 if (err)
228 return NULL;
229
230 if (f2fs_has_inline_dentry(dir)) {
231 de = find_in_inline_dir(dir, &fname, res_page);
232 goto out;
233 }
234
235 if (npages == 0)
236 goto out;
237
238 max_depth = F2FS_I(dir)->i_current_depth;
239 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
240 f2fs_msg(F2FS_I_SB(dir)->sb, KERN_WARNING,
241 "Corrupted max_depth of %lu: %u",
242 dir->i_ino, max_depth);
243 max_depth = MAX_DIR_HASH_DEPTH;
244 F2FS_I(dir)->i_current_depth = max_depth;
245 mark_inode_dirty(dir);
246 }
247
248 for (level = 0; level < max_depth; level++) {
249 de = find_in_level(dir, level, &fname, res_page);
250 if (de)
251 break;
252 }
253out:
254 fscrypt_free_filename(&fname);
255 return de;
256}
257
258struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
259{
260 struct page *page;
261 struct f2fs_dir_entry *de;
262 struct f2fs_dentry_block *dentry_blk;
263
264 if (f2fs_has_inline_dentry(dir))
265 return f2fs_parent_inline_dir(dir, p);
266
267 page = get_lock_data_page(dir, 0, false);
268 if (IS_ERR(page))
269 return NULL;
270
271 dentry_blk = kmap(page);
272 de = &dentry_blk->dentry[1];
273 *p = page;
274 unlock_page(page);
275 return de;
276}
277
278ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr)
279{
280 ino_t res = 0;
281 struct f2fs_dir_entry *de;
282 struct page *page;
283
284 de = f2fs_find_entry(dir, qstr, &page);
285 if (de) {
286 res = le32_to_cpu(de->ino);
287 f2fs_dentry_kunmap(dir, page);
288 f2fs_put_page(page, 0);
289 }
290
291 return res;
292}
293
294void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
295 struct page *page, struct inode *inode)
296{
297 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
298 lock_page(page);
299 f2fs_wait_on_page_writeback(page, type, true);
300 de->ino = cpu_to_le32(inode->i_ino);
301 set_de_type(de, inode->i_mode);
302 f2fs_dentry_kunmap(dir, page);
303 set_page_dirty(page);
304 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
305 mark_inode_dirty(dir);
306
307 f2fs_put_page(page, 1);
308}
309
310static void init_dent_inode(const struct qstr *name, struct page *ipage)
311{
312 struct f2fs_inode *ri;
313
314 f2fs_wait_on_page_writeback(ipage, NODE, true);
315
316 /* copy name info. to this inode page */
317 ri = F2FS_INODE(ipage);
318 ri->i_namelen = cpu_to_le32(name->len);
319 memcpy(ri->i_name, name->name, name->len);
320 set_page_dirty(ipage);
321}
322
323int update_dent_inode(struct inode *inode, struct inode *to,
324 const struct qstr *name)
325{
326 struct page *page;
327
328 if (file_enc_name(to))
329 return 0;
330
331 page = get_node_page(F2FS_I_SB(inode), inode->i_ino);
332 if (IS_ERR(page))
333 return PTR_ERR(page);
334
335 init_dent_inode(name, page);
336 f2fs_put_page(page, 1);
337
338 return 0;
339}
340
341void do_make_empty_dir(struct inode *inode, struct inode *parent,
342 struct f2fs_dentry_ptr *d)
343{
344 struct qstr dot = QSTR_INIT(".", 1);
345 struct qstr dotdot = QSTR_INIT("..", 2);
346
347 /* update dirent of "." */
348 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
349
350 /* update dirent of ".." */
351 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
352}
353
354static int make_empty_dir(struct inode *inode,
355 struct inode *parent, struct page *page)
356{
357 struct page *dentry_page;
358 struct f2fs_dentry_block *dentry_blk;
359 struct f2fs_dentry_ptr d;
360
361 if (f2fs_has_inline_dentry(inode))
362 return make_empty_inline_dir(inode, parent, page);
363
364 dentry_page = get_new_data_page(inode, page, 0, true);
365 if (IS_ERR(dentry_page))
366 return PTR_ERR(dentry_page);
367
368 dentry_blk = kmap_atomic(dentry_page);
369
370 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
371 do_make_empty_dir(inode, parent, &d);
372
373 kunmap_atomic(dentry_blk);
374
375 set_page_dirty(dentry_page);
376 f2fs_put_page(dentry_page, 1);
377 return 0;
378}
379
380struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
381 const struct qstr *name, struct page *dpage)
382{
383 struct page *page;
384 int err;
385
386 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
387 page = new_inode_page(inode);
388 if (IS_ERR(page))
389 return page;
390
391 if (S_ISDIR(inode->i_mode)) {
392 err = make_empty_dir(inode, dir, page);
393 if (err)
394 goto error;
395 }
396
397 err = f2fs_init_acl(inode, dir, page, dpage);
398 if (err)
399 goto put_error;
400
401 err = f2fs_init_security(inode, dir, name, page);
402 if (err)
403 goto put_error;
404
405 if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) {
406 err = fscrypt_inherit_context(dir, inode, page, false);
407 if (err)
408 goto put_error;
409 }
410 } else {
411 page = get_node_page(F2FS_I_SB(dir), inode->i_ino);
412 if (IS_ERR(page))
413 return page;
414
415 set_cold_node(inode, page);
416 }
417
418 if (name)
419 init_dent_inode(name, page);
420
421 /*
422 * This file should be checkpointed during fsync.
423 * We lost i_pino from now on.
424 */
425 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
426 file_lost_pino(inode);
427 /*
428 * If link the tmpfile to alias through linkat path,
429 * we should remove this inode from orphan list.
430 */
431 if (inode->i_nlink == 0)
432 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
433 inc_nlink(inode);
434 }
435 return page;
436
437put_error:
438 f2fs_put_page(page, 1);
439error:
440 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */
441 truncate_inode_pages(&inode->i_data, 0);
442 truncate_blocks(inode, 0, false);
443 remove_dirty_inode(inode);
444 remove_inode_page(inode);
445 return ERR_PTR(err);
446}
447
448void update_parent_metadata(struct inode *dir, struct inode *inode,
449 unsigned int current_depth)
450{
451 if (inode && is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
452 if (S_ISDIR(inode->i_mode)) {
453 inc_nlink(dir);
454 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
455 }
456 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
457 }
458 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
459 mark_inode_dirty(dir);
460
461 if (F2FS_I(dir)->i_current_depth != current_depth) {
462 F2FS_I(dir)->i_current_depth = current_depth;
463 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
464 }
465
466 if (inode && is_inode_flag_set(F2FS_I(inode), FI_INC_LINK))
467 clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
468}
469
470int room_for_filename(const void *bitmap, int slots, int max_slots)
471{
472 int bit_start = 0;
473 int zero_start, zero_end;
474next:
475 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
476 if (zero_start >= max_slots)
477 return max_slots;
478
479 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
480 if (zero_end - zero_start >= slots)
481 return zero_start;
482
483 bit_start = zero_end + 1;
484
485 if (zero_end + 1 >= max_slots)
486 return max_slots;
487 goto next;
488}
489
490void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
491 const struct qstr *name, f2fs_hash_t name_hash,
492 unsigned int bit_pos)
493{
494 struct f2fs_dir_entry *de;
495 int slots = GET_DENTRY_SLOTS(name->len);
496 int i;
497
498 de = &d->dentry[bit_pos];
499 de->hash_code = name_hash;
500 de->name_len = cpu_to_le16(name->len);
501 memcpy(d->filename[bit_pos], name->name, name->len);
502 de->ino = cpu_to_le32(ino);
503 set_de_type(de, mode);
504 for (i = 0; i < slots; i++) {
505 test_and_set_bit_le(bit_pos + i, (void *)d->bitmap);
506 /* avoid wrong garbage data for readdir */
507 if (i)
508 (de + i)->name_len = 0;
509 }
510}
511
512/*
513 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
514 * f2fs_unlock_op().
515 */
516int __f2fs_add_link(struct inode *dir, const struct qstr *name,
517 struct inode *inode, nid_t ino, umode_t mode)
518{
519 unsigned int bit_pos;
520 unsigned int level;
521 unsigned int current_depth;
522 unsigned long bidx, block;
523 f2fs_hash_t dentry_hash;
524 unsigned int nbucket, nblock;
525 struct page *dentry_page = NULL;
526 struct f2fs_dentry_block *dentry_blk = NULL;
527 struct f2fs_dentry_ptr d;
528 struct page *page = NULL;
529 struct fscrypt_name fname;
530 struct qstr new_name;
531 int slots, err;
532
533 err = fscrypt_setup_filename(dir, name, 0, &fname);
534 if (err)
535 return err;
536
537 new_name.name = fname_name(&fname);
538 new_name.len = fname_len(&fname);
539
540 if (f2fs_has_inline_dentry(dir)) {
541 err = f2fs_add_inline_entry(dir, &new_name, inode, ino, mode);
542 if (!err || err != -EAGAIN)
543 goto out;
544 else
545 err = 0;
546 }
547
548 level = 0;
549 slots = GET_DENTRY_SLOTS(new_name.len);
550 dentry_hash = f2fs_dentry_hash(&new_name);
551
552 current_depth = F2FS_I(dir)->i_current_depth;
553 if (F2FS_I(dir)->chash == dentry_hash) {
554 level = F2FS_I(dir)->clevel;
555 F2FS_I(dir)->chash = 0;
556 }
557
558start:
559 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH)) {
560 err = -ENOSPC;
561 goto out;
562 }
563
564 /* Increase the depth, if required */
565 if (level == current_depth)
566 ++current_depth;
567
568 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
569 nblock = bucket_blocks(level);
570
571 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
572 (le32_to_cpu(dentry_hash) % nbucket));
573
574 for (block = bidx; block <= (bidx + nblock - 1); block++) {
575 dentry_page = get_new_data_page(dir, NULL, block, true);
576 if (IS_ERR(dentry_page)) {
577 err = PTR_ERR(dentry_page);
578 goto out;
579 }
580
581 dentry_blk = kmap(dentry_page);
582 bit_pos = room_for_filename(&dentry_blk->dentry_bitmap,
583 slots, NR_DENTRY_IN_BLOCK);
584 if (bit_pos < NR_DENTRY_IN_BLOCK)
585 goto add_dentry;
586
587 kunmap(dentry_page);
588 f2fs_put_page(dentry_page, 1);
589 }
590
591 /* Move to next level to find the empty slot for new dentry */
592 ++level;
593 goto start;
594add_dentry:
595 f2fs_wait_on_page_writeback(dentry_page, DATA, true);
596
597 if (inode) {
598 down_write(&F2FS_I(inode)->i_sem);
599 page = init_inode_metadata(inode, dir, &new_name, NULL);
600 if (IS_ERR(page)) {
601 err = PTR_ERR(page);
602 goto fail;
603 }
604 if (f2fs_encrypted_inode(dir))
605 file_set_enc_name(inode);
606 }
607
608 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
609 f2fs_update_dentry(ino, mode, &d, &new_name, dentry_hash, bit_pos);
610
611 set_page_dirty(dentry_page);
612
613 if (inode) {
614 /* we don't need to mark_inode_dirty now */
615 F2FS_I(inode)->i_pino = dir->i_ino;
616 update_inode(inode, page);
617 f2fs_put_page(page, 1);
618 }
619
620 update_parent_metadata(dir, inode, current_depth);
621fail:
622 if (inode)
623 up_write(&F2FS_I(inode)->i_sem);
624
625 if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
626 update_inode_page(dir);
627 clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
628 }
629 kunmap(dentry_page);
630 f2fs_put_page(dentry_page, 1);
631out:
632 fscrypt_free_filename(&fname);
633 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
634 return err;
635}
636
637int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
638{
639 struct page *page;
640 int err = 0;
641
642 down_write(&F2FS_I(inode)->i_sem);
643 page = init_inode_metadata(inode, dir, NULL, NULL);
644 if (IS_ERR(page)) {
645 err = PTR_ERR(page);
646 goto fail;
647 }
648 /* we don't need to mark_inode_dirty now */
649 update_inode(inode, page);
650 f2fs_put_page(page, 1);
651
652 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
653fail:
654 up_write(&F2FS_I(inode)->i_sem);
655 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
656 return err;
657}
658
659void f2fs_drop_nlink(struct inode *dir, struct inode *inode, struct page *page)
660{
661 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
662
663 down_write(&F2FS_I(inode)->i_sem);
664
665 if (S_ISDIR(inode->i_mode)) {
666 drop_nlink(dir);
667 if (page)
668 update_inode(dir, page);
669 else
670 update_inode_page(dir);
671 }
672 inode->i_ctime = CURRENT_TIME;
673
674 drop_nlink(inode);
675 if (S_ISDIR(inode->i_mode)) {
676 drop_nlink(inode);
677 i_size_write(inode, 0);
678 }
679 up_write(&F2FS_I(inode)->i_sem);
680 update_inode_page(inode);
681
682 if (inode->i_nlink == 0)
683 add_orphan_inode(sbi, inode->i_ino);
684 else
685 release_orphan_inode(sbi);
686}
687
688/*
689 * It only removes the dentry from the dentry page, corresponding name
690 * entry in name page does not need to be touched during deletion.
691 */
692void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
693 struct inode *dir, struct inode *inode)
694{
695 struct f2fs_dentry_block *dentry_blk;
696 unsigned int bit_pos;
697 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
698 int i;
699
700 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
701
702 if (f2fs_has_inline_dentry(dir))
703 return f2fs_delete_inline_entry(dentry, page, dir, inode);
704
705 lock_page(page);
706 f2fs_wait_on_page_writeback(page, DATA, true);
707
708 dentry_blk = page_address(page);
709 bit_pos = dentry - dentry_blk->dentry;
710 for (i = 0; i < slots; i++)
711 clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
712
713 /* Let's check and deallocate this dentry page */
714 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
715 NR_DENTRY_IN_BLOCK,
716 0);
717 kunmap(page); /* kunmap - pair of f2fs_find_entry */
718 set_page_dirty(page);
719
720 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
721
722 if (inode)
723 f2fs_drop_nlink(dir, inode, NULL);
724
725 if (bit_pos == NR_DENTRY_IN_BLOCK &&
726 !truncate_hole(dir, page->index, page->index + 1)) {
727 clear_page_dirty_for_io(page);
728 ClearPagePrivate(page);
729 ClearPageUptodate(page);
730 inode_dec_dirty_pages(dir);
731 }
732 f2fs_put_page(page, 1);
733}
734
735bool f2fs_empty_dir(struct inode *dir)
736{
737 unsigned long bidx;
738 struct page *dentry_page;
739 unsigned int bit_pos;
740 struct f2fs_dentry_block *dentry_blk;
741 unsigned long nblock = dir_blocks(dir);
742
743 if (f2fs_has_inline_dentry(dir))
744 return f2fs_empty_inline_dir(dir);
745
746 for (bidx = 0; bidx < nblock; bidx++) {
747 dentry_page = get_lock_data_page(dir, bidx, false);
748 if (IS_ERR(dentry_page)) {
749 if (PTR_ERR(dentry_page) == -ENOENT)
750 continue;
751 else
752 return false;
753 }
754
755 dentry_blk = kmap_atomic(dentry_page);
756 if (bidx == 0)
757 bit_pos = 2;
758 else
759 bit_pos = 0;
760 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
761 NR_DENTRY_IN_BLOCK,
762 bit_pos);
763 kunmap_atomic(dentry_blk);
764
765 f2fs_put_page(dentry_page, 1);
766
767 if (bit_pos < NR_DENTRY_IN_BLOCK)
768 return false;
769 }
770 return true;
771}
772
773bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
774 unsigned int start_pos, struct fscrypt_str *fstr)
775{
776 unsigned char d_type = DT_UNKNOWN;
777 unsigned int bit_pos;
778 struct f2fs_dir_entry *de = NULL;
779 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
780
781 bit_pos = ((unsigned long)ctx->pos % d->max);
782
783 while (bit_pos < d->max) {
784 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
785 if (bit_pos >= d->max)
786 break;
787
788 de = &d->dentry[bit_pos];
789 if (de->name_len == 0) {
790 bit_pos++;
791 ctx->pos = start_pos + bit_pos;
792 continue;
793 }
794
795 if (de->file_type < F2FS_FT_MAX)
796 d_type = f2fs_filetype_table[de->file_type];
797 else
798 d_type = DT_UNKNOWN;
799
800 de_name.name = d->filename[bit_pos];
801 de_name.len = le16_to_cpu(de->name_len);
802
803 if (f2fs_encrypted_inode(d->inode)) {
804 int save_len = fstr->len;
805 int ret;
806
807 de_name.name = kmalloc(de_name.len, GFP_NOFS);
808 if (!de_name.name)
809 return false;
810
811 memcpy(de_name.name, d->filename[bit_pos], de_name.len);
812
813 ret = fscrypt_fname_disk_to_usr(d->inode,
814 (u32)de->hash_code, 0,
815 &de_name, fstr);
816 kfree(de_name.name);
817 if (ret < 0)
818 return true;
819
820 de_name = *fstr;
821 fstr->len = save_len;
822 }
823
824 if (!dir_emit(ctx, de_name.name, de_name.len,
825 le32_to_cpu(de->ino), d_type))
826 return true;
827
828 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
829 ctx->pos = start_pos + bit_pos;
830 }
831 return false;
832}
833
834static int f2fs_readdir(struct file *file, struct dir_context *ctx)
835{
836 struct inode *inode = file_inode(file);
837 unsigned long npages = dir_blocks(inode);
838 struct f2fs_dentry_block *dentry_blk = NULL;
839 struct page *dentry_page = NULL;
840 struct file_ra_state *ra = &file->f_ra;
841 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
842 struct f2fs_dentry_ptr d;
843 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
844 int err = 0;
845
846 if (f2fs_encrypted_inode(inode)) {
847 err = fscrypt_get_encryption_info(inode);
848 if (err && err != -ENOKEY)
849 return err;
850
851 err = fscrypt_fname_alloc_buffer(inode, F2FS_NAME_LEN, &fstr);
852 if (err < 0)
853 return err;
854 }
855
856 if (f2fs_has_inline_dentry(inode)) {
857 err = f2fs_read_inline_dir(file, ctx, &fstr);
858 goto out;
859 }
860
861 /* readahead for multi pages of dir */
862 if (npages - n > 1 && !ra_has_index(ra, n))
863 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
864 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
865
866 for (; n < npages; n++) {
867 dentry_page = get_lock_data_page(inode, n, false);
868 if (IS_ERR(dentry_page)) {
869 err = PTR_ERR(dentry_page);
870 if (err == -ENOENT)
871 continue;
872 else
873 goto out;
874 }
875
876 dentry_blk = kmap(dentry_page);
877
878 make_dentry_ptr(inode, &d, (void *)dentry_blk, 1);
879
880 if (f2fs_fill_dentries(ctx, &d, n * NR_DENTRY_IN_BLOCK, &fstr)) {
881 kunmap(dentry_page);
882 f2fs_put_page(dentry_page, 1);
883 break;
884 }
885
886 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
887 kunmap(dentry_page);
888 f2fs_put_page(dentry_page, 1);
889 }
890out:
891 fscrypt_fname_free_buffer(&fstr);
892 return err;
893}
894
895static int f2fs_dir_open(struct inode *inode, struct file *filp)
896{
897 if (f2fs_encrypted_inode(inode))
898 return fscrypt_get_encryption_info(inode) ? -EACCES : 0;
899 return 0;
900}
901
902const struct file_operations f2fs_dir_operations = {
903 .llseek = generic_file_llseek,
904 .read = generic_read_dir,
905 .iterate = f2fs_readdir,
906 .fsync = f2fs_sync_file,
907 .open = f2fs_dir_open,
908 .unlocked_ioctl = f2fs_ioctl,
909#ifdef CONFIG_COMPAT
910 .compat_ioctl = f2fs_compat_ioctl,
911#endif
912};
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};