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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#ifdef 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#ifdef CONFIG_UNICODE
83 struct super_block *sb = dir->i_sb;
84
85 if (IS_CASEFOLDED(dir)) {
86 fname->cf_name.name = kmem_cache_alloc(f2fs_cf_name_slab,
87 GFP_NOFS);
88 if (!fname->cf_name.name)
89 return -ENOMEM;
90 fname->cf_name.len = utf8_casefold(sb->s_encoding,
91 fname->usr_fname,
92 fname->cf_name.name,
93 F2FS_NAME_LEN);
94 if ((int)fname->cf_name.len <= 0) {
95 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
96 fname->cf_name.name = NULL;
97 if (sb_has_strict_encoding(sb))
98 return -EINVAL;
99 /* fall back to treating name as opaque byte sequence */
100 }
101 }
102#endif
103 return 0;
104}
105
106static int __f2fs_setup_filename(const struct inode *dir,
107 const struct fscrypt_name *crypt_name,
108 struct f2fs_filename *fname)
109{
110 int err;
111
112 memset(fname, 0, sizeof(*fname));
113
114 fname->usr_fname = crypt_name->usr_fname;
115 fname->disk_name = crypt_name->disk_name;
116#ifdef CONFIG_FS_ENCRYPTION
117 fname->crypto_buf = crypt_name->crypto_buf;
118#endif
119 if (crypt_name->is_nokey_name) {
120 /* hash was decoded from the no-key name */
121 fname->hash = cpu_to_le32(crypt_name->hash);
122 } else {
123 err = f2fs_init_casefolded_name(dir, fname);
124 if (err) {
125 f2fs_free_filename(fname);
126 return err;
127 }
128 f2fs_hash_filename(dir, fname);
129 }
130 return 0;
131}
132
133/*
134 * Prepare to search for @iname in @dir. This is similar to
135 * fscrypt_setup_filename(), but this also handles computing the casefolded name
136 * and the f2fs dirhash if needed, then packing all the information about this
137 * filename up into a 'struct f2fs_filename'.
138 */
139int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
140 int lookup, struct f2fs_filename *fname)
141{
142 struct fscrypt_name crypt_name;
143 int err;
144
145 err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);
146 if (err)
147 return err;
148
149 return __f2fs_setup_filename(dir, &crypt_name, fname);
150}
151
152/*
153 * Prepare to look up @dentry in @dir. This is similar to
154 * fscrypt_prepare_lookup(), but this also handles computing the casefolded name
155 * and the f2fs dirhash if needed, then packing all the information about this
156 * filename up into a 'struct f2fs_filename'.
157 */
158int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,
159 struct f2fs_filename *fname)
160{
161 struct fscrypt_name crypt_name;
162 int err;
163
164 err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);
165 if (err)
166 return err;
167
168 return __f2fs_setup_filename(dir, &crypt_name, fname);
169}
170
171void f2fs_free_filename(struct f2fs_filename *fname)
172{
173#ifdef CONFIG_FS_ENCRYPTION
174 kfree(fname->crypto_buf.name);
175 fname->crypto_buf.name = NULL;
176#endif
177#ifdef CONFIG_UNICODE
178 if (fname->cf_name.name) {
179 kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
180 fname->cf_name.name = NULL;
181 }
182#endif
183}
184
185static unsigned long dir_block_index(unsigned int level,
186 int dir_level, unsigned int idx)
187{
188 unsigned long i;
189 unsigned long bidx = 0;
190
191 for (i = 0; i < level; i++)
192 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
193 bidx += idx * bucket_blocks(level);
194 return bidx;
195}
196
197static struct f2fs_dir_entry *find_in_block(struct inode *dir,
198 struct page *dentry_page,
199 const struct f2fs_filename *fname,
200 int *max_slots)
201{
202 struct f2fs_dentry_block *dentry_blk;
203 struct f2fs_dentry_ptr d;
204
205 dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);
206
207 make_dentry_ptr_block(dir, &d, dentry_blk);
208 return f2fs_find_target_dentry(&d, fname, max_slots);
209}
210
211#ifdef CONFIG_UNICODE
212/*
213 * Test whether a case-insensitive directory entry matches the filename
214 * being searched for.
215 *
216 * Returns 1 for a match, 0 for no match, and -errno on an error.
217 */
218static int f2fs_match_ci_name(const struct inode *dir, const struct qstr *name,
219 const u8 *de_name, u32 de_name_len)
220{
221 const struct super_block *sb = dir->i_sb;
222 const struct unicode_map *um = sb->s_encoding;
223 struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
224 struct qstr entry = QSTR_INIT(de_name, de_name_len);
225 int res;
226
227 if (IS_ENCRYPTED(dir)) {
228 const struct fscrypt_str encrypted_name =
229 FSTR_INIT((u8 *)de_name, de_name_len);
230
231 if (WARN_ON_ONCE(!fscrypt_has_encryption_key(dir)))
232 return -EINVAL;
233
234 decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
235 if (!decrypted_name.name)
236 return -ENOMEM;
237 res = fscrypt_fname_disk_to_usr(dir, 0, 0, &encrypted_name,
238 &decrypted_name);
239 if (res < 0)
240 goto out;
241 entry.name = decrypted_name.name;
242 entry.len = decrypted_name.len;
243 }
244
245 res = utf8_strncasecmp_folded(um, name, &entry);
246 /*
247 * In strict mode, ignore invalid names. In non-strict mode,
248 * fall back to treating them as opaque byte sequences.
249 */
250 if (res < 0 && !sb_has_strict_encoding(sb)) {
251 res = name->len == entry.len &&
252 memcmp(name->name, entry.name, name->len) == 0;
253 } else {
254 /* utf8_strncasecmp_folded returns 0 on match */
255 res = (res == 0);
256 }
257out:
258 kfree(decrypted_name.name);
259 return res;
260}
261#endif /* CONFIG_UNICODE */
262
263static inline int f2fs_match_name(const struct inode *dir,
264 const struct f2fs_filename *fname,
265 const u8 *de_name, u32 de_name_len)
266{
267 struct fscrypt_name f;
268
269#ifdef CONFIG_UNICODE
270 if (fname->cf_name.name) {
271 struct qstr cf = FSTR_TO_QSTR(&fname->cf_name);
272
273 return f2fs_match_ci_name(dir, &cf, de_name, de_name_len);
274 }
275#endif
276 f.usr_fname = fname->usr_fname;
277 f.disk_name = fname->disk_name;
278#ifdef CONFIG_FS_ENCRYPTION
279 f.crypto_buf = fname->crypto_buf;
280#endif
281 return fscrypt_match_name(&f, de_name, de_name_len);
282}
283
284struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
285 const struct f2fs_filename *fname, int *max_slots)
286{
287 struct f2fs_dir_entry *de;
288 unsigned long bit_pos = 0;
289 int max_len = 0;
290 int res = 0;
291
292 if (max_slots)
293 *max_slots = 0;
294 while (bit_pos < d->max) {
295 if (!test_bit_le(bit_pos, d->bitmap)) {
296 bit_pos++;
297 max_len++;
298 continue;
299 }
300
301 de = &d->dentry[bit_pos];
302
303 if (unlikely(!de->name_len)) {
304 bit_pos++;
305 continue;
306 }
307
308 if (de->hash_code == fname->hash) {
309 res = f2fs_match_name(d->inode, fname,
310 d->filename[bit_pos],
311 le16_to_cpu(de->name_len));
312 if (res < 0)
313 return ERR_PTR(res);
314 if (res)
315 goto found;
316 }
317
318 if (max_slots && max_len > *max_slots)
319 *max_slots = max_len;
320 max_len = 0;
321
322 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
323 }
324
325 de = NULL;
326found:
327 if (max_slots && max_len > *max_slots)
328 *max_slots = max_len;
329 return de;
330}
331
332static struct f2fs_dir_entry *find_in_level(struct inode *dir,
333 unsigned int level,
334 const struct f2fs_filename *fname,
335 struct page **res_page)
336{
337 int s = GET_DENTRY_SLOTS(fname->disk_name.len);
338 unsigned int nbucket, nblock;
339 unsigned int bidx, end_block;
340 struct page *dentry_page;
341 struct f2fs_dir_entry *de = NULL;
342 bool room = false;
343 int max_slots;
344
345 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
346 nblock = bucket_blocks(level);
347
348 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
349 le32_to_cpu(fname->hash) % nbucket);
350 end_block = bidx + nblock;
351
352 for (; bidx < end_block; bidx++) {
353 /* no need to allocate new dentry pages to all the indices */
354 dentry_page = f2fs_find_data_page(dir, bidx);
355 if (IS_ERR(dentry_page)) {
356 if (PTR_ERR(dentry_page) == -ENOENT) {
357 room = true;
358 continue;
359 } else {
360 *res_page = dentry_page;
361 break;
362 }
363 }
364
365 de = find_in_block(dir, dentry_page, fname, &max_slots);
366 if (IS_ERR(de)) {
367 *res_page = ERR_CAST(de);
368 de = NULL;
369 break;
370 } else if (de) {
371 *res_page = dentry_page;
372 break;
373 }
374
375 if (max_slots >= s)
376 room = true;
377 f2fs_put_page(dentry_page, 0);
378 }
379
380 if (!de && room && F2FS_I(dir)->chash != fname->hash) {
381 F2FS_I(dir)->chash = fname->hash;
382 F2FS_I(dir)->clevel = level;
383 }
384
385 return de;
386}
387
388struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
389 const struct f2fs_filename *fname,
390 struct page **res_page)
391{
392 unsigned long npages = dir_blocks(dir);
393 struct f2fs_dir_entry *de = NULL;
394 unsigned int max_depth;
395 unsigned int level;
396
397 *res_page = NULL;
398
399 if (f2fs_has_inline_dentry(dir)) {
400 de = f2fs_find_in_inline_dir(dir, fname, res_page);
401 goto out;
402 }
403
404 if (npages == 0)
405 goto out;
406
407 max_depth = F2FS_I(dir)->i_current_depth;
408 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
409 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
410 dir->i_ino, max_depth);
411 max_depth = MAX_DIR_HASH_DEPTH;
412 f2fs_i_depth_write(dir, max_depth);
413 }
414
415 for (level = 0; level < max_depth; level++) {
416 de = find_in_level(dir, level, fname, res_page);
417 if (de || IS_ERR(*res_page))
418 break;
419 }
420out:
421 /* This is to increase the speed of f2fs_create */
422 if (!de)
423 F2FS_I(dir)->task = current;
424 return de;
425}
426
427/*
428 * Find an entry in the specified directory with the wanted name.
429 * It returns the page where the entry was found (as a parameter - res_page),
430 * and the entry itself. Page is returned mapped and unlocked.
431 * Entry is guaranteed to be valid.
432 */
433struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
434 const struct qstr *child, struct page **res_page)
435{
436 struct f2fs_dir_entry *de = NULL;
437 struct f2fs_filename fname;
438 int err;
439
440 err = f2fs_setup_filename(dir, child, 1, &fname);
441 if (err) {
442 if (err == -ENOENT)
443 *res_page = NULL;
444 else
445 *res_page = ERR_PTR(err);
446 return NULL;
447 }
448
449 de = __f2fs_find_entry(dir, &fname, res_page);
450
451 f2fs_free_filename(&fname);
452 return de;
453}
454
455struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
456{
457 return f2fs_find_entry(dir, &dotdot_name, p);
458}
459
460ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
461 struct page **page)
462{
463 ino_t res = 0;
464 struct f2fs_dir_entry *de;
465
466 de = f2fs_find_entry(dir, qstr, page);
467 if (de) {
468 res = le32_to_cpu(de->ino);
469 f2fs_put_page(*page, 0);
470 }
471
472 return res;
473}
474
475void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
476 struct page *page, struct inode *inode)
477{
478 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
479
480 lock_page(page);
481 f2fs_wait_on_page_writeback(page, type, true, true);
482 de->ino = cpu_to_le32(inode->i_ino);
483 set_de_type(de, inode->i_mode);
484 set_page_dirty(page);
485
486 dir->i_mtime = dir->i_ctime = current_time(dir);
487 f2fs_mark_inode_dirty_sync(dir, false);
488 f2fs_put_page(page, 1);
489}
490
491static void init_dent_inode(struct inode *dir, struct inode *inode,
492 const struct f2fs_filename *fname,
493 struct page *ipage)
494{
495 struct f2fs_inode *ri;
496
497 if (!fname) /* tmpfile case? */
498 return;
499
500 f2fs_wait_on_page_writeback(ipage, NODE, true, true);
501
502 /* copy name info. to this inode page */
503 ri = F2FS_INODE(ipage);
504 ri->i_namelen = cpu_to_le32(fname->disk_name.len);
505 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
506 if (IS_ENCRYPTED(dir)) {
507 file_set_enc_name(inode);
508 /*
509 * Roll-forward recovery doesn't have encryption keys available,
510 * so it can't compute the dirhash for encrypted+casefolded
511 * filenames. Append it to i_name if possible. Else, disable
512 * roll-forward recovery of the dentry (i.e., make fsync'ing the
513 * file force a checkpoint) by setting LOST_PINO.
514 */
515 if (IS_CASEFOLDED(dir)) {
516 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
517 F2FS_NAME_LEN)
518 put_unaligned(fname->hash, (f2fs_hash_t *)
519 &ri->i_name[fname->disk_name.len]);
520 else
521 file_lost_pino(inode);
522 }
523 }
524 set_page_dirty(ipage);
525}
526
527void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
528 struct f2fs_dentry_ptr *d)
529{
530 struct fscrypt_str dot = FSTR_INIT(".", 1);
531 struct fscrypt_str dotdot = FSTR_INIT("..", 2);
532
533 /* update dirent of "." */
534 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
535
536 /* update dirent of ".." */
537 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
538}
539
540static int make_empty_dir(struct inode *inode,
541 struct inode *parent, struct page *page)
542{
543 struct page *dentry_page;
544 struct f2fs_dentry_block *dentry_blk;
545 struct f2fs_dentry_ptr d;
546
547 if (f2fs_has_inline_dentry(inode))
548 return f2fs_make_empty_inline_dir(inode, parent, page);
549
550 dentry_page = f2fs_get_new_data_page(inode, page, 0, true);
551 if (IS_ERR(dentry_page))
552 return PTR_ERR(dentry_page);
553
554 dentry_blk = page_address(dentry_page);
555
556 make_dentry_ptr_block(NULL, &d, dentry_blk);
557 f2fs_do_make_empty_dir(inode, parent, &d);
558
559 set_page_dirty(dentry_page);
560 f2fs_put_page(dentry_page, 1);
561 return 0;
562}
563
564struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
565 const struct f2fs_filename *fname, struct page *dpage)
566{
567 struct page *page;
568 int err;
569
570 if (is_inode_flag_set(inode, FI_NEW_INODE)) {
571 page = f2fs_new_inode_page(inode);
572 if (IS_ERR(page))
573 return page;
574
575 if (S_ISDIR(inode->i_mode)) {
576 /* in order to handle error case */
577 get_page(page);
578 err = make_empty_dir(inode, dir, page);
579 if (err) {
580 lock_page(page);
581 goto put_error;
582 }
583 put_page(page);
584 }
585
586 err = f2fs_init_acl(inode, dir, page, dpage);
587 if (err)
588 goto put_error;
589
590 err = f2fs_init_security(inode, dir,
591 fname ? fname->usr_fname : NULL, page);
592 if (err)
593 goto put_error;
594
595 if (IS_ENCRYPTED(inode)) {
596 err = fscrypt_set_context(inode, page);
597 if (err)
598 goto put_error;
599 }
600 } else {
601 page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);
602 if (IS_ERR(page))
603 return page;
604 }
605
606 init_dent_inode(dir, inode, fname, page);
607
608 /*
609 * This file should be checkpointed during fsync.
610 * We lost i_pino from now on.
611 */
612 if (is_inode_flag_set(inode, FI_INC_LINK)) {
613 if (!S_ISDIR(inode->i_mode))
614 file_lost_pino(inode);
615 /*
616 * If link the tmpfile to alias through linkat path,
617 * we should remove this inode from orphan list.
618 */
619 if (inode->i_nlink == 0)
620 f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
621 f2fs_i_links_write(inode, true);
622 }
623 return page;
624
625put_error:
626 clear_nlink(inode);
627 f2fs_update_inode(inode, page);
628 f2fs_put_page(page, 1);
629 return ERR_PTR(err);
630}
631
632void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
633 unsigned int current_depth)
634{
635 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
636 if (S_ISDIR(inode->i_mode))
637 f2fs_i_links_write(dir, true);
638 clear_inode_flag(inode, FI_NEW_INODE);
639 }
640 dir->i_mtime = dir->i_ctime = current_time(dir);
641 f2fs_mark_inode_dirty_sync(dir, false);
642
643 if (F2FS_I(dir)->i_current_depth != current_depth)
644 f2fs_i_depth_write(dir, current_depth);
645
646 if (inode && is_inode_flag_set(inode, FI_INC_LINK))
647 clear_inode_flag(inode, FI_INC_LINK);
648}
649
650int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
651{
652 int bit_start = 0;
653 int zero_start, zero_end;
654next:
655 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
656 if (zero_start >= max_slots)
657 return max_slots;
658
659 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
660 if (zero_end - zero_start >= slots)
661 return zero_start;
662
663 bit_start = zero_end + 1;
664
665 if (zero_end + 1 >= max_slots)
666 return max_slots;
667 goto next;
668}
669
670bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
671 const struct f2fs_filename *fname)
672{
673 struct f2fs_dentry_ptr d;
674 unsigned int bit_pos;
675 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
676
677 make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
678
679 bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
680
681 return bit_pos < d.max;
682}
683
684void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
685 const struct fscrypt_str *name, f2fs_hash_t name_hash,
686 unsigned int bit_pos)
687{
688 struct f2fs_dir_entry *de;
689 int slots = GET_DENTRY_SLOTS(name->len);
690 int i;
691
692 de = &d->dentry[bit_pos];
693 de->hash_code = name_hash;
694 de->name_len = cpu_to_le16(name->len);
695 memcpy(d->filename[bit_pos], name->name, name->len);
696 de->ino = cpu_to_le32(ino);
697 set_de_type(de, mode);
698 for (i = 0; i < slots; i++) {
699 __set_bit_le(bit_pos + i, (void *)d->bitmap);
700 /* avoid wrong garbage data for readdir */
701 if (i)
702 (de + i)->name_len = 0;
703 }
704}
705
706int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
707 struct inode *inode, nid_t ino, umode_t mode)
708{
709 unsigned int bit_pos;
710 unsigned int level;
711 unsigned int current_depth;
712 unsigned long bidx, block;
713 unsigned int nbucket, nblock;
714 struct page *dentry_page = NULL;
715 struct f2fs_dentry_block *dentry_blk = NULL;
716 struct f2fs_dentry_ptr d;
717 struct page *page = NULL;
718 int slots, err = 0;
719
720 level = 0;
721 slots = GET_DENTRY_SLOTS(fname->disk_name.len);
722
723 current_depth = F2FS_I(dir)->i_current_depth;
724 if (F2FS_I(dir)->chash == fname->hash) {
725 level = F2FS_I(dir)->clevel;
726 F2FS_I(dir)->chash = 0;
727 }
728
729start:
730 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH)) {
731 f2fs_show_injection_info(F2FS_I_SB(dir), FAULT_DIR_DEPTH);
732 return -ENOSPC;
733 }
734
735 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
736 return -ENOSPC;
737
738 /* Increase the depth, if required */
739 if (level == current_depth)
740 ++current_depth;
741
742 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
743 nblock = bucket_blocks(level);
744
745 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
746 (le32_to_cpu(fname->hash) % nbucket));
747
748 for (block = bidx; block <= (bidx + nblock - 1); block++) {
749 dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);
750 if (IS_ERR(dentry_page))
751 return PTR_ERR(dentry_page);
752
753 dentry_blk = page_address(dentry_page);
754 bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,
755 slots, NR_DENTRY_IN_BLOCK);
756 if (bit_pos < NR_DENTRY_IN_BLOCK)
757 goto add_dentry;
758
759 f2fs_put_page(dentry_page, 1);
760 }
761
762 /* Move to next level to find the empty slot for new dentry */
763 ++level;
764 goto start;
765add_dentry:
766 f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);
767
768 if (inode) {
769 down_write(&F2FS_I(inode)->i_sem);
770 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
771 if (IS_ERR(page)) {
772 err = PTR_ERR(page);
773 goto fail;
774 }
775 }
776
777 make_dentry_ptr_block(NULL, &d, dentry_blk);
778 f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,
779 bit_pos);
780
781 set_page_dirty(dentry_page);
782
783 if (inode) {
784 f2fs_i_pino_write(inode, dir->i_ino);
785
786 /* synchronize inode page's data from inode cache */
787 if (is_inode_flag_set(inode, FI_NEW_INODE))
788 f2fs_update_inode(inode, page);
789
790 f2fs_put_page(page, 1);
791 }
792
793 f2fs_update_parent_metadata(dir, inode, current_depth);
794fail:
795 if (inode)
796 up_write(&F2FS_I(inode)->i_sem);
797
798 f2fs_put_page(dentry_page, 1);
799
800 return err;
801}
802
803int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
804 struct inode *inode, nid_t ino, umode_t mode)
805{
806 int err = -EAGAIN;
807
808 if (f2fs_has_inline_dentry(dir))
809 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
810 if (err == -EAGAIN)
811 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
812
813 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
814 return err;
815}
816
817/*
818 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
819 * f2fs_unlock_op().
820 */
821int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
822 struct inode *inode, nid_t ino, umode_t mode)
823{
824 struct f2fs_filename fname;
825 struct page *page = NULL;
826 struct f2fs_dir_entry *de = NULL;
827 int err;
828
829 err = f2fs_setup_filename(dir, name, 0, &fname);
830 if (err)
831 return err;
832
833 /*
834 * An immature stackable filesystem shows a race condition between lookup
835 * and create. If we have same task when doing lookup and create, it's
836 * definitely fine as expected by VFS normally. Otherwise, let's just
837 * verify on-disk dentry one more time, which guarantees filesystem
838 * consistency more.
839 */
840 if (current != F2FS_I(dir)->task) {
841 de = __f2fs_find_entry(dir, &fname, &page);
842 F2FS_I(dir)->task = NULL;
843 }
844 if (de) {
845 f2fs_put_page(page, 0);
846 err = -EEXIST;
847 } else if (IS_ERR(page)) {
848 err = PTR_ERR(page);
849 } else {
850 err = f2fs_add_dentry(dir, &fname, inode, ino, mode);
851 }
852 f2fs_free_filename(&fname);
853 return err;
854}
855
856int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
857{
858 struct page *page;
859 int err = 0;
860
861 down_write(&F2FS_I(inode)->i_sem);
862 page = f2fs_init_inode_metadata(inode, dir, NULL, NULL);
863 if (IS_ERR(page)) {
864 err = PTR_ERR(page);
865 goto fail;
866 }
867 f2fs_put_page(page, 1);
868
869 clear_inode_flag(inode, FI_NEW_INODE);
870 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
871fail:
872 up_write(&F2FS_I(inode)->i_sem);
873 return err;
874}
875
876void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
877{
878 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
879
880 down_write(&F2FS_I(inode)->i_sem);
881
882 if (S_ISDIR(inode->i_mode))
883 f2fs_i_links_write(dir, false);
884 inode->i_ctime = current_time(inode);
885
886 f2fs_i_links_write(inode, false);
887 if (S_ISDIR(inode->i_mode)) {
888 f2fs_i_links_write(inode, false);
889 f2fs_i_size_write(inode, 0);
890 }
891 up_write(&F2FS_I(inode)->i_sem);
892
893 if (inode->i_nlink == 0)
894 f2fs_add_orphan_inode(inode);
895 else
896 f2fs_release_orphan_inode(sbi);
897}
898
899/*
900 * It only removes the dentry from the dentry page, corresponding name
901 * entry in name page does not need to be touched during deletion.
902 */
903void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
904 struct inode *dir, struct inode *inode)
905{
906 struct f2fs_dentry_block *dentry_blk;
907 unsigned int bit_pos;
908 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
909 int i;
910
911 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
912
913 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
914 f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);
915
916 if (f2fs_has_inline_dentry(dir))
917 return f2fs_delete_inline_entry(dentry, page, dir, inode);
918
919 lock_page(page);
920 f2fs_wait_on_page_writeback(page, DATA, true, true);
921
922 dentry_blk = page_address(page);
923 bit_pos = dentry - dentry_blk->dentry;
924 for (i = 0; i < slots; i++)
925 __clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
926
927 /* Let's check and deallocate this dentry page */
928 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
929 NR_DENTRY_IN_BLOCK,
930 0);
931 set_page_dirty(page);
932
933 if (bit_pos == NR_DENTRY_IN_BLOCK &&
934 !f2fs_truncate_hole(dir, page->index, page->index + 1)) {
935 f2fs_clear_page_cache_dirty_tag(page);
936 clear_page_dirty_for_io(page);
937 ClearPageUptodate(page);
938
939 clear_page_private_gcing(page);
940
941 inode_dec_dirty_pages(dir);
942 f2fs_remove_dirty_inode(dir);
943
944 detach_page_private(page);
945 set_page_private(page, 0);
946 }
947 f2fs_put_page(page, 1);
948
949 dir->i_ctime = dir->i_mtime = current_time(dir);
950 f2fs_mark_inode_dirty_sync(dir, false);
951
952 if (inode)
953 f2fs_drop_nlink(dir, inode);
954}
955
956bool f2fs_empty_dir(struct inode *dir)
957{
958 unsigned long bidx;
959 struct page *dentry_page;
960 unsigned int bit_pos;
961 struct f2fs_dentry_block *dentry_blk;
962 unsigned long nblock = dir_blocks(dir);
963
964 if (f2fs_has_inline_dentry(dir))
965 return f2fs_empty_inline_dir(dir);
966
967 for (bidx = 0; bidx < nblock; bidx++) {
968 dentry_page = f2fs_get_lock_data_page(dir, bidx, false);
969 if (IS_ERR(dentry_page)) {
970 if (PTR_ERR(dentry_page) == -ENOENT)
971 continue;
972 else
973 return false;
974 }
975
976 dentry_blk = page_address(dentry_page);
977 if (bidx == 0)
978 bit_pos = 2;
979 else
980 bit_pos = 0;
981 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
982 NR_DENTRY_IN_BLOCK,
983 bit_pos);
984
985 f2fs_put_page(dentry_page, 1);
986
987 if (bit_pos < NR_DENTRY_IN_BLOCK)
988 return false;
989 }
990 return true;
991}
992
993int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
994 unsigned int start_pos, struct fscrypt_str *fstr)
995{
996 unsigned char d_type = DT_UNKNOWN;
997 unsigned int bit_pos;
998 struct f2fs_dir_entry *de = NULL;
999 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
1000 struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
1001 struct blk_plug plug;
1002 bool readdir_ra = sbi->readdir_ra == 1;
1003 bool found_valid_dirent = false;
1004 int err = 0;
1005
1006 bit_pos = ((unsigned long)ctx->pos % d->max);
1007
1008 if (readdir_ra)
1009 blk_start_plug(&plug);
1010
1011 while (bit_pos < d->max) {
1012 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
1013 if (bit_pos >= d->max)
1014 break;
1015
1016 de = &d->dentry[bit_pos];
1017 if (de->name_len == 0) {
1018 if (found_valid_dirent || !bit_pos) {
1019 printk_ratelimited(
1020 "%sF2FS-fs (%s): invalid namelen(0), ino:%u, run fsck to fix.",
1021 KERN_WARNING, sbi->sb->s_id,
1022 le32_to_cpu(de->ino));
1023 set_sbi_flag(sbi, SBI_NEED_FSCK);
1024 }
1025 bit_pos++;
1026 ctx->pos = start_pos + bit_pos;
1027 continue;
1028 }
1029
1030 d_type = f2fs_get_de_type(de);
1031
1032 de_name.name = d->filename[bit_pos];
1033 de_name.len = le16_to_cpu(de->name_len);
1034
1035 /* check memory boundary before moving forward */
1036 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
1037 if (unlikely(bit_pos > d->max ||
1038 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
1039 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
1040 __func__, le16_to_cpu(de->name_len));
1041 set_sbi_flag(sbi, SBI_NEED_FSCK);
1042 err = -EFSCORRUPTED;
1043 goto out;
1044 }
1045
1046 if (IS_ENCRYPTED(d->inode)) {
1047 int save_len = fstr->len;
1048
1049 err = fscrypt_fname_disk_to_usr(d->inode,
1050 (u32)le32_to_cpu(de->hash_code),
1051 0, &de_name, fstr);
1052 if (err)
1053 goto out;
1054
1055 de_name = *fstr;
1056 fstr->len = save_len;
1057 }
1058
1059 if (!dir_emit(ctx, de_name.name, de_name.len,
1060 le32_to_cpu(de->ino), d_type)) {
1061 err = 1;
1062 goto out;
1063 }
1064
1065 if (readdir_ra)
1066 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
1067
1068 ctx->pos = start_pos + bit_pos;
1069 found_valid_dirent = true;
1070 }
1071out:
1072 if (readdir_ra)
1073 blk_finish_plug(&plug);
1074 return err;
1075}
1076
1077static int f2fs_readdir(struct file *file, struct dir_context *ctx)
1078{
1079 struct inode *inode = file_inode(file);
1080 unsigned long npages = dir_blocks(inode);
1081 struct f2fs_dentry_block *dentry_blk = NULL;
1082 struct page *dentry_page = NULL;
1083 struct file_ra_state *ra = &file->f_ra;
1084 loff_t start_pos = ctx->pos;
1085 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
1086 struct f2fs_dentry_ptr d;
1087 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
1088 int err = 0;
1089
1090 if (IS_ENCRYPTED(inode)) {
1091 err = fscrypt_prepare_readdir(inode);
1092 if (err)
1093 goto out;
1094
1095 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);
1096 if (err < 0)
1097 goto out;
1098 }
1099
1100 if (f2fs_has_inline_dentry(inode)) {
1101 err = f2fs_read_inline_dir(file, ctx, &fstr);
1102 goto out_free;
1103 }
1104
1105 for (; n < npages; n++, ctx->pos = n * NR_DENTRY_IN_BLOCK) {
1106
1107 /* allow readdir() to be interrupted */
1108 if (fatal_signal_pending(current)) {
1109 err = -ERESTARTSYS;
1110 goto out_free;
1111 }
1112 cond_resched();
1113
1114 /* readahead for multi pages of dir */
1115 if (npages - n > 1 && !ra_has_index(ra, n))
1116 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
1117 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
1118
1119 dentry_page = f2fs_find_data_page(inode, n);
1120 if (IS_ERR(dentry_page)) {
1121 err = PTR_ERR(dentry_page);
1122 if (err == -ENOENT) {
1123 err = 0;
1124 continue;
1125 } else {
1126 goto out_free;
1127 }
1128 }
1129
1130 dentry_blk = page_address(dentry_page);
1131
1132 make_dentry_ptr_block(inode, &d, dentry_blk);
1133
1134 err = f2fs_fill_dentries(ctx, &d,
1135 n * NR_DENTRY_IN_BLOCK, &fstr);
1136 if (err) {
1137 f2fs_put_page(dentry_page, 0);
1138 break;
1139 }
1140
1141 f2fs_put_page(dentry_page, 0);
1142 }
1143out_free:
1144 fscrypt_fname_free_buffer(&fstr);
1145out:
1146 trace_f2fs_readdir(inode, start_pos, ctx->pos, err);
1147 return err < 0 ? err : 0;
1148}
1149
1150const struct file_operations f2fs_dir_operations = {
1151 .llseek = generic_file_llseek,
1152 .read = generic_read_dir,
1153 .iterate_shared = f2fs_readdir,
1154 .fsync = f2fs_sync_file,
1155 .unlocked_ioctl = f2fs_ioctl,
1156#ifdef CONFIG_COMPAT
1157 .compat_ioctl = f2fs_compat_ioctl,
1158#endif
1159};