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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
40static unsigned 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
51static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
52 [S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE,
53 [S_IFDIR >> S_SHIFT] = F2FS_FT_DIR,
54 [S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV,
55 [S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV,
56 [S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO,
57 [S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK,
58 [S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK,
59};
60
61void set_de_type(struct f2fs_dir_entry *de, umode_t mode)
62{
63 de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
64}
65
66unsigned char get_de_type(struct f2fs_dir_entry *de)
67{
68 if (de->file_type < F2FS_FT_MAX)
69 return f2fs_filetype_table[de->file_type];
70 return DT_UNKNOWN;
71}
72
73static unsigned long dir_block_index(unsigned int level,
74 int dir_level, unsigned int idx)
75{
76 unsigned long i;
77 unsigned long bidx = 0;
78
79 for (i = 0; i < level; i++)
80 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
81 bidx += idx * bucket_blocks(level);
82 return bidx;
83}
84
85static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
86 struct fscrypt_name *fname,
87 f2fs_hash_t namehash,
88 int *max_slots,
89 struct page **res_page)
90{
91 struct f2fs_dentry_block *dentry_blk;
92 struct f2fs_dir_entry *de;
93 struct f2fs_dentry_ptr d;
94
95 dentry_blk = (struct f2fs_dentry_block *)kmap(dentry_page);
96
97 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
98 de = find_target_dentry(fname, namehash, max_slots, &d);
99 if (de)
100 *res_page = dentry_page;
101 else
102 kunmap(dentry_page);
103
104 return de;
105}
106
107struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
108 f2fs_hash_t namehash, int *max_slots,
109 struct f2fs_dentry_ptr *d)
110{
111 struct f2fs_dir_entry *de;
112 unsigned long bit_pos = 0;
113 int max_len = 0;
114 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
115 struct fscrypt_str *name = &fname->disk_name;
116
117 if (max_slots)
118 *max_slots = 0;
119 while (bit_pos < d->max) {
120 if (!test_bit_le(bit_pos, d->bitmap)) {
121 bit_pos++;
122 max_len++;
123 continue;
124 }
125
126 de = &d->dentry[bit_pos];
127
128 if (unlikely(!de->name_len)) {
129 bit_pos++;
130 continue;
131 }
132
133 /* encrypted case */
134 de_name.name = d->filename[bit_pos];
135 de_name.len = le16_to_cpu(de->name_len);
136
137 /* show encrypted name */
138 if (fname->hash) {
139 if (de->hash_code == cpu_to_le32(fname->hash))
140 goto found;
141 } else if (de_name.len == name->len &&
142 de->hash_code == namehash &&
143 !memcmp(de_name.name, name->name, name->len))
144 goto found;
145
146 if (max_slots && max_len > *max_slots)
147 *max_slots = max_len;
148 max_len = 0;
149
150 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
151 }
152
153 de = NULL;
154found:
155 if (max_slots && max_len > *max_slots)
156 *max_slots = max_len;
157 return de;
158}
159
160static struct f2fs_dir_entry *find_in_level(struct inode *dir,
161 unsigned int level,
162 struct fscrypt_name *fname,
163 struct page **res_page)
164{
165 struct qstr name = FSTR_TO_QSTR(&fname->disk_name);
166 int s = GET_DENTRY_SLOTS(name.len);
167 unsigned int nbucket, nblock;
168 unsigned int bidx, end_block;
169 struct page *dentry_page;
170 struct f2fs_dir_entry *de = NULL;
171 bool room = false;
172 int max_slots;
173 f2fs_hash_t namehash;
174
175 if(fname->hash)
176 namehash = cpu_to_le32(fname->hash);
177 else
178 namehash = f2fs_dentry_hash(&name);
179
180 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
181 nblock = bucket_blocks(level);
182
183 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
184 le32_to_cpu(namehash) % nbucket);
185 end_block = bidx + nblock;
186
187 for (; bidx < end_block; bidx++) {
188 /* no need to allocate new dentry pages to all the indices */
189 dentry_page = find_data_page(dir, bidx);
190 if (IS_ERR(dentry_page)) {
191 if (PTR_ERR(dentry_page) == -ENOENT) {
192 room = true;
193 continue;
194 } else {
195 *res_page = dentry_page;
196 break;
197 }
198 }
199
200 de = find_in_block(dentry_page, fname, namehash, &max_slots,
201 res_page);
202 if (de)
203 break;
204
205 if (max_slots >= s)
206 room = true;
207 f2fs_put_page(dentry_page, 0);
208 }
209
210 /* This is to increase the speed of f2fs_create */
211 if (!de && room) {
212 F2FS_I(dir)->task = current;
213 if (F2FS_I(dir)->chash != namehash) {
214 F2FS_I(dir)->chash = namehash;
215 F2FS_I(dir)->clevel = level;
216 }
217 }
218
219 return de;
220}
221
222struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
223 struct fscrypt_name *fname, struct page **res_page)
224{
225 unsigned long npages = dir_blocks(dir);
226 struct f2fs_dir_entry *de = NULL;
227 unsigned int max_depth;
228 unsigned int level;
229
230 if (f2fs_has_inline_dentry(dir)) {
231 *res_page = NULL;
232 de = find_in_inline_dir(dir, fname, res_page);
233 goto out;
234 }
235
236 if (npages == 0) {
237 *res_page = NULL;
238 goto out;
239 }
240
241 max_depth = F2FS_I(dir)->i_current_depth;
242 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
243 f2fs_msg(F2FS_I_SB(dir)->sb, KERN_WARNING,
244 "Corrupted max_depth of %lu: %u",
245 dir->i_ino, max_depth);
246 max_depth = MAX_DIR_HASH_DEPTH;
247 f2fs_i_depth_write(dir, max_depth);
248 }
249
250 for (level = 0; level < max_depth; level++) {
251 *res_page = NULL;
252 de = find_in_level(dir, level, fname, res_page);
253 if (de || IS_ERR(*res_page))
254 break;
255 }
256out:
257 return de;
258}
259
260/*
261 * Find an entry in the specified directory with the wanted name.
262 * It returns the page where the entry was found (as a parameter - res_page),
263 * and the entry itself. Page is returned mapped and unlocked.
264 * Entry is guaranteed to be valid.
265 */
266struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
267 const struct qstr *child, struct page **res_page)
268{
269 struct f2fs_dir_entry *de = NULL;
270 struct fscrypt_name fname;
271 int err;
272
273 err = fscrypt_setup_filename(dir, child, 1, &fname);
274 if (err) {
275 *res_page = ERR_PTR(err);
276 return NULL;
277 }
278
279 de = __f2fs_find_entry(dir, &fname, res_page);
280
281 fscrypt_free_filename(&fname);
282 return de;
283}
284
285struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
286{
287 struct qstr dotdot = QSTR_INIT("..", 2);
288
289 return f2fs_find_entry(dir, &dotdot, p);
290}
291
292ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
293 struct page **page)
294{
295 ino_t res = 0;
296 struct f2fs_dir_entry *de;
297
298 de = f2fs_find_entry(dir, qstr, page);
299 if (de) {
300 res = le32_to_cpu(de->ino);
301 f2fs_dentry_kunmap(dir, *page);
302 f2fs_put_page(*page, 0);
303 }
304
305 return res;
306}
307
308void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
309 struct page *page, struct inode *inode)
310{
311 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
312 lock_page(page);
313 f2fs_wait_on_page_writeback(page, type, true);
314 de->ino = cpu_to_le32(inode->i_ino);
315 set_de_type(de, inode->i_mode);
316 f2fs_dentry_kunmap(dir, page);
317 set_page_dirty(page);
318
319 dir->i_mtime = dir->i_ctime = current_time(dir);
320 f2fs_mark_inode_dirty_sync(dir, false);
321 f2fs_put_page(page, 1);
322}
323
324static void init_dent_inode(const struct qstr *name, struct page *ipage)
325{
326 struct f2fs_inode *ri;
327
328 f2fs_wait_on_page_writeback(ipage, NODE, true);
329
330 /* copy name info. to this inode page */
331 ri = F2FS_INODE(ipage);
332 ri->i_namelen = cpu_to_le32(name->len);
333 memcpy(ri->i_name, name->name, name->len);
334 set_page_dirty(ipage);
335}
336
337int update_dent_inode(struct inode *inode, struct inode *to,
338 const struct qstr *name)
339{
340 struct page *page;
341
342 if (file_enc_name(to))
343 return 0;
344
345 page = get_node_page(F2FS_I_SB(inode), inode->i_ino);
346 if (IS_ERR(page))
347 return PTR_ERR(page);
348
349 init_dent_inode(name, page);
350 f2fs_put_page(page, 1);
351
352 return 0;
353}
354
355void do_make_empty_dir(struct inode *inode, struct inode *parent,
356 struct f2fs_dentry_ptr *d)
357{
358 struct qstr dot = QSTR_INIT(".", 1);
359 struct qstr dotdot = QSTR_INIT("..", 2);
360
361 /* update dirent of "." */
362 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
363
364 /* update dirent of ".." */
365 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
366}
367
368static int make_empty_dir(struct inode *inode,
369 struct inode *parent, struct page *page)
370{
371 struct page *dentry_page;
372 struct f2fs_dentry_block *dentry_blk;
373 struct f2fs_dentry_ptr d;
374
375 if (f2fs_has_inline_dentry(inode))
376 return make_empty_inline_dir(inode, parent, page);
377
378 dentry_page = get_new_data_page(inode, page, 0, true);
379 if (IS_ERR(dentry_page))
380 return PTR_ERR(dentry_page);
381
382 dentry_blk = kmap_atomic(dentry_page);
383
384 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
385 do_make_empty_dir(inode, parent, &d);
386
387 kunmap_atomic(dentry_blk);
388
389 set_page_dirty(dentry_page);
390 f2fs_put_page(dentry_page, 1);
391 return 0;
392}
393
394struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
395 const struct qstr *new_name, const struct qstr *orig_name,
396 struct page *dpage)
397{
398 struct page *page;
399 int err;
400
401 if (is_inode_flag_set(inode, FI_NEW_INODE)) {
402 page = new_inode_page(inode);
403 if (IS_ERR(page))
404 return page;
405
406 if (S_ISDIR(inode->i_mode)) {
407 /* in order to handle error case */
408 get_page(page);
409 err = make_empty_dir(inode, dir, page);
410 if (err) {
411 lock_page(page);
412 goto put_error;
413 }
414 put_page(page);
415 }
416
417 err = f2fs_init_acl(inode, dir, page, dpage);
418 if (err)
419 goto put_error;
420
421 err = f2fs_init_security(inode, dir, orig_name, page);
422 if (err)
423 goto put_error;
424
425 if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) {
426 err = fscrypt_inherit_context(dir, inode, page, false);
427 if (err)
428 goto put_error;
429 }
430 } else {
431 page = get_node_page(F2FS_I_SB(dir), inode->i_ino);
432 if (IS_ERR(page))
433 return page;
434
435 set_cold_node(inode, page);
436 }
437
438 if (new_name)
439 init_dent_inode(new_name, page);
440
441 /*
442 * This file should be checkpointed during fsync.
443 * We lost i_pino from now on.
444 */
445 if (is_inode_flag_set(inode, FI_INC_LINK)) {
446 file_lost_pino(inode);
447 /*
448 * If link the tmpfile to alias through linkat path,
449 * we should remove this inode from orphan list.
450 */
451 if (inode->i_nlink == 0)
452 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
453 f2fs_i_links_write(inode, true);
454 }
455 return page;
456
457put_error:
458 clear_nlink(inode);
459 update_inode(inode, page);
460 f2fs_put_page(page, 1);
461 return ERR_PTR(err);
462}
463
464void update_parent_metadata(struct inode *dir, struct inode *inode,
465 unsigned int current_depth)
466{
467 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
468 if (S_ISDIR(inode->i_mode))
469 f2fs_i_links_write(dir, true);
470 clear_inode_flag(inode, FI_NEW_INODE);
471 }
472 dir->i_mtime = dir->i_ctime = current_time(dir);
473 f2fs_mark_inode_dirty_sync(dir, false);
474
475 if (F2FS_I(dir)->i_current_depth != current_depth)
476 f2fs_i_depth_write(dir, current_depth);
477
478 if (inode && is_inode_flag_set(inode, FI_INC_LINK))
479 clear_inode_flag(inode, FI_INC_LINK);
480}
481
482int room_for_filename(const void *bitmap, int slots, int max_slots)
483{
484 int bit_start = 0;
485 int zero_start, zero_end;
486next:
487 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
488 if (zero_start >= max_slots)
489 return max_slots;
490
491 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
492 if (zero_end - zero_start >= slots)
493 return zero_start;
494
495 bit_start = zero_end + 1;
496
497 if (zero_end + 1 >= max_slots)
498 return max_slots;
499 goto next;
500}
501
502void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
503 const struct qstr *name, f2fs_hash_t name_hash,
504 unsigned int bit_pos)
505{
506 struct f2fs_dir_entry *de;
507 int slots = GET_DENTRY_SLOTS(name->len);
508 int i;
509
510 de = &d->dentry[bit_pos];
511 de->hash_code = name_hash;
512 de->name_len = cpu_to_le16(name->len);
513 memcpy(d->filename[bit_pos], name->name, name->len);
514 de->ino = cpu_to_le32(ino);
515 set_de_type(de, mode);
516 for (i = 0; i < slots; i++) {
517 __set_bit_le(bit_pos + i, (void *)d->bitmap);
518 /* avoid wrong garbage data for readdir */
519 if (i)
520 (de + i)->name_len = 0;
521 }
522}
523
524int f2fs_add_regular_entry(struct inode *dir, const struct qstr *new_name,
525 const struct qstr *orig_name,
526 struct inode *inode, nid_t ino, umode_t mode)
527{
528 unsigned int bit_pos;
529 unsigned int level;
530 unsigned int current_depth;
531 unsigned long bidx, block;
532 f2fs_hash_t dentry_hash;
533 unsigned int nbucket, nblock;
534 struct page *dentry_page = NULL;
535 struct f2fs_dentry_block *dentry_blk = NULL;
536 struct f2fs_dentry_ptr d;
537 struct page *page = NULL;
538 int slots, err = 0;
539
540 level = 0;
541 slots = GET_DENTRY_SLOTS(new_name->len);
542 dentry_hash = f2fs_dentry_hash(new_name);
543
544 current_depth = F2FS_I(dir)->i_current_depth;
545 if (F2FS_I(dir)->chash == dentry_hash) {
546 level = F2FS_I(dir)->clevel;
547 F2FS_I(dir)->chash = 0;
548 }
549
550start:
551#ifdef CONFIG_F2FS_FAULT_INJECTION
552 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))
553 return -ENOSPC;
554#endif
555 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
556 return -ENOSPC;
557
558 /* Increase the depth, if required */
559 if (level == current_depth)
560 ++current_depth;
561
562 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
563 nblock = bucket_blocks(level);
564
565 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
566 (le32_to_cpu(dentry_hash) % nbucket));
567
568 for (block = bidx; block <= (bidx + nblock - 1); block++) {
569 dentry_page = get_new_data_page(dir, NULL, block, true);
570 if (IS_ERR(dentry_page))
571 return PTR_ERR(dentry_page);
572
573 dentry_blk = kmap(dentry_page);
574 bit_pos = room_for_filename(&dentry_blk->dentry_bitmap,
575 slots, NR_DENTRY_IN_BLOCK);
576 if (bit_pos < NR_DENTRY_IN_BLOCK)
577 goto add_dentry;
578
579 kunmap(dentry_page);
580 f2fs_put_page(dentry_page, 1);
581 }
582
583 /* Move to next level to find the empty slot for new dentry */
584 ++level;
585 goto start;
586add_dentry:
587 f2fs_wait_on_page_writeback(dentry_page, DATA, true);
588
589 if (inode) {
590 down_write(&F2FS_I(inode)->i_sem);
591 page = init_inode_metadata(inode, dir, new_name,
592 orig_name, NULL);
593 if (IS_ERR(page)) {
594 err = PTR_ERR(page);
595 goto fail;
596 }
597 if (f2fs_encrypted_inode(dir))
598 file_set_enc_name(inode);
599 }
600
601 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1);
602 f2fs_update_dentry(ino, mode, &d, new_name, dentry_hash, bit_pos);
603
604 set_page_dirty(dentry_page);
605
606 if (inode) {
607 f2fs_i_pino_write(inode, dir->i_ino);
608 f2fs_put_page(page, 1);
609 }
610
611 update_parent_metadata(dir, inode, current_depth);
612fail:
613 if (inode)
614 up_write(&F2FS_I(inode)->i_sem);
615
616 kunmap(dentry_page);
617 f2fs_put_page(dentry_page, 1);
618
619 return err;
620}
621
622int __f2fs_do_add_link(struct inode *dir, struct fscrypt_name *fname,
623 struct inode *inode, nid_t ino, umode_t mode)
624{
625 struct qstr new_name;
626 int err = -EAGAIN;
627
628 new_name.name = fname_name(fname);
629 new_name.len = fname_len(fname);
630
631 if (f2fs_has_inline_dentry(dir))
632 err = f2fs_add_inline_entry(dir, &new_name, fname->usr_fname,
633 inode, ino, mode);
634 if (err == -EAGAIN)
635 err = f2fs_add_regular_entry(dir, &new_name, fname->usr_fname,
636 inode, ino, mode);
637
638 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
639 return err;
640}
641
642/*
643 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
644 * f2fs_unlock_op().
645 */
646int __f2fs_add_link(struct inode *dir, const struct qstr *name,
647 struct inode *inode, nid_t ino, umode_t mode)
648{
649 struct fscrypt_name fname;
650 struct page *page = NULL;
651 struct f2fs_dir_entry *de = NULL;
652 int err;
653
654 err = fscrypt_setup_filename(dir, name, 0, &fname);
655 if (err)
656 return err;
657
658 /*
659 * An immature stakable filesystem shows a race condition between lookup
660 * and create. If we have same task when doing lookup and create, it's
661 * definitely fine as expected by VFS normally. Otherwise, let's just
662 * verify on-disk dentry one more time, which guarantees filesystem
663 * consistency more.
664 */
665 if (current != F2FS_I(dir)->task) {
666 de = __f2fs_find_entry(dir, &fname, &page);
667 F2FS_I(dir)->task = NULL;
668 }
669 if (de) {
670 f2fs_dentry_kunmap(dir, page);
671 f2fs_put_page(page, 0);
672 err = -EEXIST;
673 } else if (IS_ERR(page)) {
674 err = PTR_ERR(page);
675 } else {
676 err = __f2fs_do_add_link(dir, &fname, inode, ino, mode);
677 }
678 fscrypt_free_filename(&fname);
679 return err;
680}
681
682int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
683{
684 struct page *page;
685 int err = 0;
686
687 down_write(&F2FS_I(inode)->i_sem);
688 page = init_inode_metadata(inode, dir, NULL, NULL, NULL);
689 if (IS_ERR(page)) {
690 err = PTR_ERR(page);
691 goto fail;
692 }
693 f2fs_put_page(page, 1);
694
695 clear_inode_flag(inode, FI_NEW_INODE);
696fail:
697 up_write(&F2FS_I(inode)->i_sem);
698 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
699 return err;
700}
701
702void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
703{
704 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
705
706 down_write(&F2FS_I(inode)->i_sem);
707
708 if (S_ISDIR(inode->i_mode))
709 f2fs_i_links_write(dir, false);
710 inode->i_ctime = current_time(inode);
711
712 f2fs_i_links_write(inode, false);
713 if (S_ISDIR(inode->i_mode)) {
714 f2fs_i_links_write(inode, false);
715 f2fs_i_size_write(inode, 0);
716 }
717 up_write(&F2FS_I(inode)->i_sem);
718
719 if (inode->i_nlink == 0)
720 add_orphan_inode(inode);
721 else
722 release_orphan_inode(sbi);
723}
724
725/*
726 * It only removes the dentry from the dentry page, corresponding name
727 * entry in name page does not need to be touched during deletion.
728 */
729void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
730 struct inode *dir, struct inode *inode)
731{
732 struct f2fs_dentry_block *dentry_blk;
733 unsigned int bit_pos;
734 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
735 int i;
736
737 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
738
739 if (f2fs_has_inline_dentry(dir))
740 return f2fs_delete_inline_entry(dentry, page, dir, inode);
741
742 lock_page(page);
743 f2fs_wait_on_page_writeback(page, DATA, true);
744
745 dentry_blk = page_address(page);
746 bit_pos = dentry - dentry_blk->dentry;
747 for (i = 0; i < slots; i++)
748 clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
749
750 /* Let's check and deallocate this dentry page */
751 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
752 NR_DENTRY_IN_BLOCK,
753 0);
754 kunmap(page); /* kunmap - pair of f2fs_find_entry */
755 set_page_dirty(page);
756
757 dir->i_ctime = dir->i_mtime = current_time(dir);
758 f2fs_mark_inode_dirty_sync(dir, false);
759
760 if (inode)
761 f2fs_drop_nlink(dir, inode);
762
763 if (bit_pos == NR_DENTRY_IN_BLOCK &&
764 !truncate_hole(dir, page->index, page->index + 1)) {
765 clear_page_dirty_for_io(page);
766 ClearPagePrivate(page);
767 ClearPageUptodate(page);
768 inode_dec_dirty_pages(dir);
769 remove_dirty_inode(dir);
770 }
771 f2fs_put_page(page, 1);
772}
773
774bool f2fs_empty_dir(struct inode *dir)
775{
776 unsigned long bidx;
777 struct page *dentry_page;
778 unsigned int bit_pos;
779 struct f2fs_dentry_block *dentry_blk;
780 unsigned long nblock = dir_blocks(dir);
781
782 if (f2fs_has_inline_dentry(dir))
783 return f2fs_empty_inline_dir(dir);
784
785 for (bidx = 0; bidx < nblock; bidx++) {
786 dentry_page = get_lock_data_page(dir, bidx, false);
787 if (IS_ERR(dentry_page)) {
788 if (PTR_ERR(dentry_page) == -ENOENT)
789 continue;
790 else
791 return false;
792 }
793
794 dentry_blk = kmap_atomic(dentry_page);
795 if (bidx == 0)
796 bit_pos = 2;
797 else
798 bit_pos = 0;
799 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
800 NR_DENTRY_IN_BLOCK,
801 bit_pos);
802 kunmap_atomic(dentry_blk);
803
804 f2fs_put_page(dentry_page, 1);
805
806 if (bit_pos < NR_DENTRY_IN_BLOCK)
807 return false;
808 }
809 return true;
810}
811
812int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
813 unsigned int start_pos, struct fscrypt_str *fstr)
814{
815 unsigned char d_type = DT_UNKNOWN;
816 unsigned int bit_pos;
817 struct f2fs_dir_entry *de = NULL;
818 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
819
820 bit_pos = ((unsigned long)ctx->pos % d->max);
821
822 while (bit_pos < d->max) {
823 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
824 if (bit_pos >= d->max)
825 break;
826
827 de = &d->dentry[bit_pos];
828 if (de->name_len == 0) {
829 bit_pos++;
830 ctx->pos = start_pos + bit_pos;
831 continue;
832 }
833
834 d_type = get_de_type(de);
835
836 de_name.name = d->filename[bit_pos];
837 de_name.len = le16_to_cpu(de->name_len);
838
839 if (f2fs_encrypted_inode(d->inode)) {
840 int save_len = fstr->len;
841 int err;
842
843 err = fscrypt_fname_disk_to_usr(d->inode,
844 (u32)de->hash_code, 0,
845 &de_name, fstr);
846 if (err)
847 return err;
848
849 de_name = *fstr;
850 fstr->len = save_len;
851 }
852
853 if (!dir_emit(ctx, de_name.name, de_name.len,
854 le32_to_cpu(de->ino), d_type))
855 return 1;
856
857 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
858 ctx->pos = start_pos + bit_pos;
859 }
860 return 0;
861}
862
863static int f2fs_readdir(struct file *file, struct dir_context *ctx)
864{
865 struct inode *inode = file_inode(file);
866 unsigned long npages = dir_blocks(inode);
867 struct f2fs_dentry_block *dentry_blk = NULL;
868 struct page *dentry_page = NULL;
869 struct file_ra_state *ra = &file->f_ra;
870 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
871 struct f2fs_dentry_ptr d;
872 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
873 int err = 0;
874
875 if (f2fs_encrypted_inode(inode)) {
876 err = fscrypt_get_encryption_info(inode);
877 if (err && err != -ENOKEY)
878 return err;
879
880 err = fscrypt_fname_alloc_buffer(inode, F2FS_NAME_LEN, &fstr);
881 if (err < 0)
882 return err;
883 }
884
885 if (f2fs_has_inline_dentry(inode)) {
886 err = f2fs_read_inline_dir(file, ctx, &fstr);
887 goto out;
888 }
889
890 /* readahead for multi pages of dir */
891 if (npages - n > 1 && !ra_has_index(ra, n))
892 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
893 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
894
895 for (; n < npages; n++) {
896 dentry_page = get_lock_data_page(inode, n, false);
897 if (IS_ERR(dentry_page)) {
898 err = PTR_ERR(dentry_page);
899 if (err == -ENOENT) {
900 err = 0;
901 continue;
902 } else {
903 goto out;
904 }
905 }
906
907 dentry_blk = kmap(dentry_page);
908
909 make_dentry_ptr(inode, &d, (void *)dentry_blk, 1);
910
911 err = f2fs_fill_dentries(ctx, &d,
912 n * NR_DENTRY_IN_BLOCK, &fstr);
913 if (err) {
914 kunmap(dentry_page);
915 f2fs_put_page(dentry_page, 1);
916 break;
917 }
918
919 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
920 kunmap(dentry_page);
921 f2fs_put_page(dentry_page, 1);
922 }
923out:
924 fscrypt_fname_free_buffer(&fstr);
925 return err < 0 ? err : 0;
926}
927
928static int f2fs_dir_open(struct inode *inode, struct file *filp)
929{
930 if (f2fs_encrypted_inode(inode))
931 return fscrypt_get_encryption_info(inode) ? -EACCES : 0;
932 return 0;
933}
934
935const struct file_operations f2fs_dir_operations = {
936 .llseek = generic_file_llseek,
937 .read = generic_read_dir,
938 .iterate_shared = f2fs_readdir,
939 .fsync = f2fs_sync_file,
940 .open = f2fs_dir_open,
941 .unlocked_ioctl = f2fs_ioctl,
942#ifdef CONFIG_COMPAT
943 .compat_ioctl = f2fs_compat_ioctl,
944#endif
945};