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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_CACHE_SIZE - 1))
21 >> PAGE_CACHE_SHIFT;
22}
23
24static unsigned int dir_buckets(unsigned int level, int dir_level)
25{
26 if (level < MAX_DIR_HASH_DEPTH / 2)
27 return 1 << (level + dir_level);
28 else
29 return 1 << ((MAX_DIR_HASH_DEPTH / 2 + dir_level) - 1);
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
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
62static void set_de_type(struct f2fs_dir_entry *de, struct inode *inode)
63{
64 umode_t mode = inode->i_mode;
65 de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
66}
67
68static unsigned long dir_block_index(unsigned int level,
69 int dir_level, unsigned int idx)
70{
71 unsigned long i;
72 unsigned long bidx = 0;
73
74 for (i = 0; i < level; i++)
75 bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
76 bidx += idx * bucket_blocks(level);
77 return bidx;
78}
79
80static bool early_match_name(const char *name, size_t namelen,
81 f2fs_hash_t namehash, struct f2fs_dir_entry *de)
82{
83 if (le16_to_cpu(de->name_len) != namelen)
84 return false;
85
86 if (de->hash_code != namehash)
87 return false;
88
89 return true;
90}
91
92static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
93 const char *name, size_t namelen, int *max_slots,
94 f2fs_hash_t namehash, struct page **res_page)
95{
96 struct f2fs_dir_entry *de;
97 unsigned long bit_pos = 0;
98 struct f2fs_dentry_block *dentry_blk = kmap(dentry_page);
99 const void *dentry_bits = &dentry_blk->dentry_bitmap;
100 int max_len = 0;
101
102 while (bit_pos < NR_DENTRY_IN_BLOCK) {
103 if (!test_bit_le(bit_pos, dentry_bits)) {
104 if (bit_pos == 0)
105 max_len = 1;
106 else if (!test_bit_le(bit_pos - 1, dentry_bits))
107 max_len++;
108 bit_pos++;
109 continue;
110 }
111 de = &dentry_blk->dentry[bit_pos];
112 if (early_match_name(name, namelen, namehash, de)) {
113 if (!memcmp(dentry_blk->filename[bit_pos],
114 name, namelen)) {
115 *res_page = dentry_page;
116 goto found;
117 }
118 }
119 if (max_len > *max_slots) {
120 *max_slots = max_len;
121 max_len = 0;
122 }
123 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
124 }
125
126 de = NULL;
127 kunmap(dentry_page);
128found:
129 if (max_len > *max_slots)
130 *max_slots = max_len;
131 return de;
132}
133
134static struct f2fs_dir_entry *find_in_level(struct inode *dir,
135 unsigned int level, const char *name, size_t namelen,
136 f2fs_hash_t namehash, struct page **res_page)
137{
138 int s = GET_DENTRY_SLOTS(namelen);
139 unsigned int nbucket, nblock;
140 unsigned int bidx, end_block;
141 struct page *dentry_page;
142 struct f2fs_dir_entry *de = NULL;
143 bool room = false;
144 int max_slots = 0;
145
146 f2fs_bug_on(level > MAX_DIR_HASH_DEPTH);
147
148 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
149 nblock = bucket_blocks(level);
150
151 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
152 le32_to_cpu(namehash) % nbucket);
153 end_block = bidx + nblock;
154
155 for (; bidx < end_block; bidx++) {
156 /* no need to allocate new dentry pages to all the indices */
157 dentry_page = find_data_page(dir, bidx, true);
158 if (IS_ERR(dentry_page)) {
159 room = true;
160 continue;
161 }
162
163 de = find_in_block(dentry_page, name, namelen,
164 &max_slots, namehash, res_page);
165 if (de)
166 break;
167
168 if (max_slots >= s)
169 room = true;
170 f2fs_put_page(dentry_page, 0);
171 }
172
173 if (!de && room && F2FS_I(dir)->chash != namehash) {
174 F2FS_I(dir)->chash = namehash;
175 F2FS_I(dir)->clevel = level;
176 }
177
178 return de;
179}
180
181/*
182 * Find an entry in the specified directory with the wanted name.
183 * It returns the page where the entry was found (as a parameter - res_page),
184 * and the entry itself. Page is returned mapped and unlocked.
185 * Entry is guaranteed to be valid.
186 */
187struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
188 struct qstr *child, struct page **res_page)
189{
190 const char *name = child->name;
191 size_t namelen = child->len;
192 unsigned long npages = dir_blocks(dir);
193 struct f2fs_dir_entry *de = NULL;
194 f2fs_hash_t name_hash;
195 unsigned int max_depth;
196 unsigned int level;
197
198 if (npages == 0)
199 return NULL;
200
201 *res_page = NULL;
202
203 name_hash = f2fs_dentry_hash(name, namelen);
204 max_depth = F2FS_I(dir)->i_current_depth;
205
206 for (level = 0; level < max_depth; level++) {
207 de = find_in_level(dir, level, name,
208 namelen, name_hash, res_page);
209 if (de)
210 break;
211 }
212 if (!de && F2FS_I(dir)->chash != name_hash) {
213 F2FS_I(dir)->chash = name_hash;
214 F2FS_I(dir)->clevel = level - 1;
215 }
216 return de;
217}
218
219struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
220{
221 struct page *page;
222 struct f2fs_dir_entry *de;
223 struct f2fs_dentry_block *dentry_blk;
224
225 page = get_lock_data_page(dir, 0);
226 if (IS_ERR(page))
227 return NULL;
228
229 dentry_blk = kmap(page);
230 de = &dentry_blk->dentry[1];
231 *p = page;
232 unlock_page(page);
233 return de;
234}
235
236ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr)
237{
238 ino_t res = 0;
239 struct f2fs_dir_entry *de;
240 struct page *page;
241
242 de = f2fs_find_entry(dir, qstr, &page);
243 if (de) {
244 res = le32_to_cpu(de->ino);
245 kunmap(page);
246 f2fs_put_page(page, 0);
247 }
248
249 return res;
250}
251
252void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
253 struct page *page, struct inode *inode)
254{
255 lock_page(page);
256 f2fs_wait_on_page_writeback(page, DATA);
257 de->ino = cpu_to_le32(inode->i_ino);
258 set_de_type(de, inode);
259 kunmap(page);
260 set_page_dirty(page);
261 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
262 mark_inode_dirty(dir);
263
264 f2fs_put_page(page, 1);
265}
266
267static void init_dent_inode(const struct qstr *name, struct page *ipage)
268{
269 struct f2fs_inode *ri;
270
271 /* copy name info. to this inode page */
272 ri = F2FS_INODE(ipage);
273 ri->i_namelen = cpu_to_le32(name->len);
274 memcpy(ri->i_name, name->name, name->len);
275 set_page_dirty(ipage);
276}
277
278int update_dent_inode(struct inode *inode, const struct qstr *name)
279{
280 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
281 struct page *page;
282
283 page = get_node_page(sbi, inode->i_ino);
284 if (IS_ERR(page))
285 return PTR_ERR(page);
286
287 init_dent_inode(name, page);
288 f2fs_put_page(page, 1);
289
290 return 0;
291}
292
293static int make_empty_dir(struct inode *inode,
294 struct inode *parent, struct page *page)
295{
296 struct page *dentry_page;
297 struct f2fs_dentry_block *dentry_blk;
298 struct f2fs_dir_entry *de;
299 void *kaddr;
300
301 dentry_page = get_new_data_page(inode, page, 0, true);
302 if (IS_ERR(dentry_page))
303 return PTR_ERR(dentry_page);
304
305 kaddr = kmap_atomic(dentry_page);
306 dentry_blk = (struct f2fs_dentry_block *)kaddr;
307
308 de = &dentry_blk->dentry[0];
309 de->name_len = cpu_to_le16(1);
310 de->hash_code = 0;
311 de->ino = cpu_to_le32(inode->i_ino);
312 memcpy(dentry_blk->filename[0], ".", 1);
313 set_de_type(de, inode);
314
315 de = &dentry_blk->dentry[1];
316 de->hash_code = 0;
317 de->name_len = cpu_to_le16(2);
318 de->ino = cpu_to_le32(parent->i_ino);
319 memcpy(dentry_blk->filename[1], "..", 2);
320 set_de_type(de, inode);
321
322 test_and_set_bit_le(0, &dentry_blk->dentry_bitmap);
323 test_and_set_bit_le(1, &dentry_blk->dentry_bitmap);
324 kunmap_atomic(kaddr);
325
326 set_page_dirty(dentry_page);
327 f2fs_put_page(dentry_page, 1);
328 return 0;
329}
330
331static struct page *init_inode_metadata(struct inode *inode,
332 struct inode *dir, const struct qstr *name)
333{
334 struct page *page;
335 int err;
336
337 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
338 page = new_inode_page(inode, name);
339 if (IS_ERR(page))
340 return page;
341
342 if (S_ISDIR(inode->i_mode)) {
343 err = make_empty_dir(inode, dir, page);
344 if (err)
345 goto error;
346 }
347
348 err = f2fs_init_acl(inode, dir, page);
349 if (err)
350 goto put_error;
351
352 err = f2fs_init_security(inode, dir, name, page);
353 if (err)
354 goto put_error;
355 } else {
356 page = get_node_page(F2FS_SB(dir->i_sb), inode->i_ino);
357 if (IS_ERR(page))
358 return page;
359
360 set_cold_node(inode, page);
361 }
362
363 init_dent_inode(name, page);
364
365 /*
366 * This file should be checkpointed during fsync.
367 * We lost i_pino from now on.
368 */
369 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
370 file_lost_pino(inode);
371 inc_nlink(inode);
372 }
373 return page;
374
375put_error:
376 f2fs_put_page(page, 1);
377 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */
378 truncate_inode_pages(&inode->i_data, 0);
379 truncate_blocks(inode, 0);
380 remove_dirty_dir_inode(inode);
381error:
382 remove_inode_page(inode);
383 return ERR_PTR(err);
384}
385
386static void update_parent_metadata(struct inode *dir, struct inode *inode,
387 unsigned int current_depth)
388{
389 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
390 if (S_ISDIR(inode->i_mode)) {
391 inc_nlink(dir);
392 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
393 }
394 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
395 }
396 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
397 mark_inode_dirty(dir);
398
399 if (F2FS_I(dir)->i_current_depth != current_depth) {
400 F2FS_I(dir)->i_current_depth = current_depth;
401 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
402 }
403
404 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK))
405 clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
406}
407
408static int room_for_filename(struct f2fs_dentry_block *dentry_blk, int slots)
409{
410 int bit_start = 0;
411 int zero_start, zero_end;
412next:
413 zero_start = find_next_zero_bit_le(&dentry_blk->dentry_bitmap,
414 NR_DENTRY_IN_BLOCK,
415 bit_start);
416 if (zero_start >= NR_DENTRY_IN_BLOCK)
417 return NR_DENTRY_IN_BLOCK;
418
419 zero_end = find_next_bit_le(&dentry_blk->dentry_bitmap,
420 NR_DENTRY_IN_BLOCK,
421 zero_start);
422 if (zero_end - zero_start >= slots)
423 return zero_start;
424
425 bit_start = zero_end + 1;
426
427 if (zero_end + 1 >= NR_DENTRY_IN_BLOCK)
428 return NR_DENTRY_IN_BLOCK;
429 goto next;
430}
431
432/*
433 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
434 * f2fs_unlock_op().
435 */
436int __f2fs_add_link(struct inode *dir, const struct qstr *name,
437 struct inode *inode)
438{
439 unsigned int bit_pos;
440 unsigned int level;
441 unsigned int current_depth;
442 unsigned long bidx, block;
443 f2fs_hash_t dentry_hash;
444 struct f2fs_dir_entry *de;
445 unsigned int nbucket, nblock;
446 size_t namelen = name->len;
447 struct page *dentry_page = NULL;
448 struct f2fs_dentry_block *dentry_blk = NULL;
449 int slots = GET_DENTRY_SLOTS(namelen);
450 struct page *page;
451 int err = 0;
452 int i;
453
454 dentry_hash = f2fs_dentry_hash(name->name, name->len);
455 level = 0;
456 current_depth = F2FS_I(dir)->i_current_depth;
457 if (F2FS_I(dir)->chash == dentry_hash) {
458 level = F2FS_I(dir)->clevel;
459 F2FS_I(dir)->chash = 0;
460 }
461
462start:
463 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
464 return -ENOSPC;
465
466 /* Increase the depth, if required */
467 if (level == current_depth)
468 ++current_depth;
469
470 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
471 nblock = bucket_blocks(level);
472
473 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
474 (le32_to_cpu(dentry_hash) % nbucket));
475
476 for (block = bidx; block <= (bidx + nblock - 1); block++) {
477 dentry_page = get_new_data_page(dir, NULL, block, true);
478 if (IS_ERR(dentry_page))
479 return PTR_ERR(dentry_page);
480
481 dentry_blk = kmap(dentry_page);
482 bit_pos = room_for_filename(dentry_blk, slots);
483 if (bit_pos < NR_DENTRY_IN_BLOCK)
484 goto add_dentry;
485
486 kunmap(dentry_page);
487 f2fs_put_page(dentry_page, 1);
488 }
489
490 /* Move to next level to find the empty slot for new dentry */
491 ++level;
492 goto start;
493add_dentry:
494 f2fs_wait_on_page_writeback(dentry_page, DATA);
495
496 down_write(&F2FS_I(inode)->i_sem);
497 page = init_inode_metadata(inode, dir, name);
498 if (IS_ERR(page)) {
499 err = PTR_ERR(page);
500 goto fail;
501 }
502 de = &dentry_blk->dentry[bit_pos];
503 de->hash_code = dentry_hash;
504 de->name_len = cpu_to_le16(namelen);
505 memcpy(dentry_blk->filename[bit_pos], name->name, name->len);
506 de->ino = cpu_to_le32(inode->i_ino);
507 set_de_type(de, inode);
508 for (i = 0; i < slots; i++)
509 test_and_set_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
510 set_page_dirty(dentry_page);
511
512 /* we don't need to mark_inode_dirty now */
513 F2FS_I(inode)->i_pino = dir->i_ino;
514 update_inode(inode, page);
515 f2fs_put_page(page, 1);
516
517 update_parent_metadata(dir, inode, current_depth);
518fail:
519 up_write(&F2FS_I(inode)->i_sem);
520
521 if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
522 update_inode_page(dir);
523 clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
524 }
525 kunmap(dentry_page);
526 f2fs_put_page(dentry_page, 1);
527 return err;
528}
529
530/*
531 * It only removes the dentry from the dentry page,corresponding name
532 * entry in name page does not need to be touched during deletion.
533 */
534void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
535 struct inode *inode)
536{
537 struct f2fs_dentry_block *dentry_blk;
538 unsigned int bit_pos;
539 struct address_space *mapping = page->mapping;
540 struct inode *dir = mapping->host;
541 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
542 void *kaddr = page_address(page);
543 int i;
544
545 lock_page(page);
546 f2fs_wait_on_page_writeback(page, DATA);
547
548 dentry_blk = (struct f2fs_dentry_block *)kaddr;
549 bit_pos = dentry - (struct f2fs_dir_entry *)dentry_blk->dentry;
550 for (i = 0; i < slots; i++)
551 test_and_clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
552
553 /* Let's check and deallocate this dentry page */
554 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
555 NR_DENTRY_IN_BLOCK,
556 0);
557 kunmap(page); /* kunmap - pair of f2fs_find_entry */
558 set_page_dirty(page);
559
560 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
561
562 if (inode) {
563 struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
564
565 down_write(&F2FS_I(inode)->i_sem);
566
567 if (S_ISDIR(inode->i_mode)) {
568 drop_nlink(dir);
569 update_inode_page(dir);
570 }
571 inode->i_ctime = CURRENT_TIME;
572 drop_nlink(inode);
573 if (S_ISDIR(inode->i_mode)) {
574 drop_nlink(inode);
575 i_size_write(inode, 0);
576 }
577 up_write(&F2FS_I(inode)->i_sem);
578 update_inode_page(inode);
579
580 if (inode->i_nlink == 0)
581 add_orphan_inode(sbi, inode->i_ino);
582 else
583 release_orphan_inode(sbi);
584 }
585
586 if (bit_pos == NR_DENTRY_IN_BLOCK) {
587 truncate_hole(dir, page->index, page->index + 1);
588 clear_page_dirty_for_io(page);
589 ClearPageUptodate(page);
590 inode_dec_dirty_dents(dir);
591 }
592 f2fs_put_page(page, 1);
593}
594
595bool f2fs_empty_dir(struct inode *dir)
596{
597 unsigned long bidx;
598 struct page *dentry_page;
599 unsigned int bit_pos;
600 struct f2fs_dentry_block *dentry_blk;
601 unsigned long nblock = dir_blocks(dir);
602
603 for (bidx = 0; bidx < nblock; bidx++) {
604 void *kaddr;
605 dentry_page = get_lock_data_page(dir, bidx);
606 if (IS_ERR(dentry_page)) {
607 if (PTR_ERR(dentry_page) == -ENOENT)
608 continue;
609 else
610 return false;
611 }
612
613 kaddr = kmap_atomic(dentry_page);
614 dentry_blk = (struct f2fs_dentry_block *)kaddr;
615 if (bidx == 0)
616 bit_pos = 2;
617 else
618 bit_pos = 0;
619 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
620 NR_DENTRY_IN_BLOCK,
621 bit_pos);
622 kunmap_atomic(kaddr);
623
624 f2fs_put_page(dentry_page, 1);
625
626 if (bit_pos < NR_DENTRY_IN_BLOCK)
627 return false;
628 }
629 return true;
630}
631
632static int f2fs_readdir(struct file *file, struct dir_context *ctx)
633{
634 struct inode *inode = file_inode(file);
635 unsigned long npages = dir_blocks(inode);
636 unsigned int bit_pos = 0;
637 struct f2fs_dentry_block *dentry_blk = NULL;
638 struct f2fs_dir_entry *de = NULL;
639 struct page *dentry_page = NULL;
640 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
641 unsigned char d_type = DT_UNKNOWN;
642
643 bit_pos = ((unsigned long)ctx->pos % NR_DENTRY_IN_BLOCK);
644
645 for (; n < npages; n++) {
646 dentry_page = get_lock_data_page(inode, n);
647 if (IS_ERR(dentry_page))
648 continue;
649
650 dentry_blk = kmap(dentry_page);
651 while (bit_pos < NR_DENTRY_IN_BLOCK) {
652 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
653 NR_DENTRY_IN_BLOCK,
654 bit_pos);
655 if (bit_pos >= NR_DENTRY_IN_BLOCK)
656 break;
657
658 de = &dentry_blk->dentry[bit_pos];
659 if (de->file_type < F2FS_FT_MAX)
660 d_type = f2fs_filetype_table[de->file_type];
661 else
662 d_type = DT_UNKNOWN;
663 if (!dir_emit(ctx,
664 dentry_blk->filename[bit_pos],
665 le16_to_cpu(de->name_len),
666 le32_to_cpu(de->ino), d_type))
667 goto stop;
668
669 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
670 ctx->pos = n * NR_DENTRY_IN_BLOCK + bit_pos;
671 }
672 bit_pos = 0;
673 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
674 kunmap(dentry_page);
675 f2fs_put_page(dentry_page, 1);
676 dentry_page = NULL;
677 }
678stop:
679 if (dentry_page && !IS_ERR(dentry_page)) {
680 kunmap(dentry_page);
681 f2fs_put_page(dentry_page, 1);
682 }
683
684 return 0;
685}
686
687const struct file_operations f2fs_dir_operations = {
688 .llseek = generic_file_llseek,
689 .read = generic_read_dir,
690 .iterate = f2fs_readdir,
691 .fsync = f2fs_sync_file,
692 .unlocked_ioctl = f2fs_ioctl,
693};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * fs/f2fs/dir.c
4 *
5 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6 * http://www.samsung.com/
7 */
8#include <linux/unaligned.h>
9#include <linux/fs.h>
10#include <linux/f2fs_fs.h>
11#include <linux/sched/signal.h>
12#include <linux/unicode.h>
13#include "f2fs.h"
14#include "node.h"
15#include "acl.h"
16#include "xattr.h"
17#include <trace/events/f2fs.h>
18
19#if IS_ENABLED(CONFIG_UNICODE)
20extern struct kmem_cache *f2fs_cf_name_slab;
21#endif
22
23static unsigned long dir_blocks(struct inode *inode)
24{
25 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
26 >> PAGE_SHIFT;
27}
28
29static unsigned int dir_buckets(unsigned int level, int dir_level)
30{
31 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
32 return BIT(level + dir_level);
33 else
34 return MAX_DIR_BUCKETS;
35}
36
37static unsigned int bucket_blocks(unsigned int level)
38{
39 if (level < MAX_DIR_HASH_DEPTH / 2)
40 return 2;
41 else
42 return 4;
43}
44
45#if IS_ENABLED(CONFIG_UNICODE)
46/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */
47int f2fs_init_casefolded_name(const struct inode *dir,
48 struct f2fs_filename *fname)
49{
50 struct super_block *sb = dir->i_sb;
51 unsigned char *buf;
52 int len;
53
54 if (IS_CASEFOLDED(dir) &&
55 !is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
56 buf = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
57 GFP_NOFS, false, F2FS_SB(sb));
58 if (!buf)
59 return -ENOMEM;
60
61 len = utf8_casefold(sb->s_encoding, fname->usr_fname,
62 buf, F2FS_NAME_LEN);
63 if (len <= 0) {
64 kmem_cache_free(f2fs_cf_name_slab, buf);
65 if (sb_has_strict_encoding(sb))
66 return -EINVAL;
67 /* fall back to treating name as opaque byte sequence */
68 return 0;
69 }
70 fname->cf_name.name = buf;
71 fname->cf_name.len = len;
72 }
73
74 return 0;
75}
76
77void f2fs_free_casefolded_name(struct f2fs_filename *fname)
78{
79 unsigned char *buf = (unsigned char *)fname->cf_name.name;
80
81 if (buf) {
82 kmem_cache_free(f2fs_cf_name_slab, buf);
83 fname->cf_name.name = NULL;
84 }
85}
86#endif /* CONFIG_UNICODE */
87
88static int __f2fs_setup_filename(const struct inode *dir,
89 const struct fscrypt_name *crypt_name,
90 struct f2fs_filename *fname)
91{
92 int err;
93
94 memset(fname, 0, sizeof(*fname));
95
96 fname->usr_fname = crypt_name->usr_fname;
97 fname->disk_name = crypt_name->disk_name;
98#ifdef CONFIG_FS_ENCRYPTION
99 fname->crypto_buf = crypt_name->crypto_buf;
100#endif
101 if (crypt_name->is_nokey_name) {
102 /* hash was decoded from the no-key name */
103 fname->hash = cpu_to_le32(crypt_name->hash);
104 } else {
105 err = f2fs_init_casefolded_name(dir, fname);
106 if (err) {
107 f2fs_free_filename(fname);
108 return err;
109 }
110 f2fs_hash_filename(dir, fname);
111 }
112 return 0;
113}
114
115/*
116 * Prepare to search for @iname in @dir. This is similar to
117 * fscrypt_setup_filename(), but this also handles computing the casefolded name
118 * and the f2fs dirhash if needed, then packing all the information about this
119 * filename up into a 'struct f2fs_filename'.
120 */
121int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
122 int lookup, struct f2fs_filename *fname)
123{
124 struct fscrypt_name crypt_name;
125 int err;
126
127 err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);
128 if (err)
129 return err;
130
131 return __f2fs_setup_filename(dir, &crypt_name, fname);
132}
133
134/*
135 * Prepare to look up @dentry in @dir. This is similar to
136 * fscrypt_prepare_lookup(), 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_prepare_lookup(struct inode *dir, struct dentry *dentry,
141 struct f2fs_filename *fname)
142{
143 struct fscrypt_name crypt_name;
144 int err;
145
146 err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);
147 if (err)
148 return err;
149
150 return __f2fs_setup_filename(dir, &crypt_name, fname);
151}
152
153void f2fs_free_filename(struct f2fs_filename *fname)
154{
155#ifdef CONFIG_FS_ENCRYPTION
156 kfree(fname->crypto_buf.name);
157 fname->crypto_buf.name = NULL;
158#endif
159 f2fs_free_casefolded_name(fname);
160}
161
162static unsigned long dir_block_index(unsigned int level,
163 int dir_level, unsigned int idx)
164{
165 unsigned long i;
166 unsigned long bidx = 0;
167
168 for (i = 0; i < level; i++)
169 bidx += mul_u32_u32(dir_buckets(i, dir_level),
170 bucket_blocks(i));
171 bidx += idx * bucket_blocks(level);
172 return bidx;
173}
174
175static struct f2fs_dir_entry *find_in_block(struct inode *dir,
176 struct page *dentry_page,
177 const struct f2fs_filename *fname,
178 int *max_slots,
179 bool use_hash)
180{
181 struct f2fs_dentry_block *dentry_blk;
182 struct f2fs_dentry_ptr d;
183
184 dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);
185
186 make_dentry_ptr_block(dir, &d, dentry_blk);
187 return f2fs_find_target_dentry(&d, fname, max_slots, use_hash);
188}
189
190static inline int f2fs_match_name(const struct inode *dir,
191 const struct f2fs_filename *fname,
192 const u8 *de_name, u32 de_name_len)
193{
194 struct fscrypt_name f;
195
196#if IS_ENABLED(CONFIG_UNICODE)
197 if (fname->cf_name.name)
198 return generic_ci_match(dir, fname->usr_fname,
199 &fname->cf_name,
200 de_name, de_name_len);
201
202#endif
203 f.usr_fname = fname->usr_fname;
204 f.disk_name = fname->disk_name;
205#ifdef CONFIG_FS_ENCRYPTION
206 f.crypto_buf = fname->crypto_buf;
207#endif
208 return fscrypt_match_name(&f, de_name, de_name_len);
209}
210
211struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
212 const struct f2fs_filename *fname, int *max_slots,
213 bool use_hash)
214{
215 struct f2fs_dir_entry *de;
216 unsigned long bit_pos = 0;
217 int max_len = 0;
218 int res = 0;
219
220 if (max_slots)
221 *max_slots = 0;
222 while (bit_pos < d->max) {
223 if (!test_bit_le(bit_pos, d->bitmap)) {
224 bit_pos++;
225 max_len++;
226 continue;
227 }
228
229 de = &d->dentry[bit_pos];
230
231 if (unlikely(!de->name_len)) {
232 bit_pos++;
233 continue;
234 }
235
236 if (!use_hash || de->hash_code == fname->hash) {
237 res = f2fs_match_name(d->inode, fname,
238 d->filename[bit_pos],
239 le16_to_cpu(de->name_len));
240 if (res < 0)
241 return ERR_PTR(res);
242 if (res)
243 goto found;
244 }
245
246 if (max_slots && max_len > *max_slots)
247 *max_slots = max_len;
248 max_len = 0;
249
250 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
251 }
252
253 de = NULL;
254found:
255 if (max_slots && max_len > *max_slots)
256 *max_slots = max_len;
257 return de;
258}
259
260static struct f2fs_dir_entry *find_in_level(struct inode *dir,
261 unsigned int level,
262 const struct f2fs_filename *fname,
263 struct page **res_page,
264 bool use_hash)
265{
266 int s = GET_DENTRY_SLOTS(fname->disk_name.len);
267 unsigned int nbucket, nblock;
268 unsigned int bidx, end_block, bucket_no;
269 struct page *dentry_page;
270 struct f2fs_dir_entry *de = NULL;
271 pgoff_t next_pgofs;
272 bool room = false;
273 int max_slots;
274
275 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
276 nblock = bucket_blocks(level);
277
278 bucket_no = use_hash ? le32_to_cpu(fname->hash) % nbucket : 0;
279
280start_find_bucket:
281 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
282 bucket_no);
283 end_block = bidx + nblock;
284
285 while (bidx < end_block) {
286 /* no need to allocate new dentry pages to all the indices */
287 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
288 if (IS_ERR(dentry_page)) {
289 if (PTR_ERR(dentry_page) == -ENOENT) {
290 room = true;
291 bidx = next_pgofs;
292 continue;
293 } else {
294 *res_page = dentry_page;
295 break;
296 }
297 }
298
299 de = find_in_block(dir, dentry_page, fname, &max_slots, use_hash);
300 if (IS_ERR(de)) {
301 *res_page = ERR_CAST(de);
302 de = NULL;
303 break;
304 } else if (de) {
305 *res_page = dentry_page;
306 break;
307 }
308
309 if (max_slots >= s)
310 room = true;
311 f2fs_put_page(dentry_page, 0);
312
313 bidx++;
314 }
315
316 if (de)
317 return de;
318
319 if (likely(use_hash)) {
320 if (room && F2FS_I(dir)->chash != fname->hash) {
321 F2FS_I(dir)->chash = fname->hash;
322 F2FS_I(dir)->clevel = level;
323 }
324 } else if (++bucket_no < nbucket) {
325 goto start_find_bucket;
326 }
327 return NULL;
328}
329
330struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
331 const struct f2fs_filename *fname,
332 struct page **res_page)
333{
334 unsigned long npages = dir_blocks(dir);
335 struct f2fs_dir_entry *de = NULL;
336 unsigned int max_depth;
337 unsigned int level;
338 bool use_hash = true;
339
340 *res_page = NULL;
341
342#if IS_ENABLED(CONFIG_UNICODE)
343start_find_entry:
344#endif
345 if (f2fs_has_inline_dentry(dir)) {
346 de = f2fs_find_in_inline_dir(dir, fname, res_page, use_hash);
347 goto out;
348 }
349
350 if (npages == 0)
351 goto out;
352
353 max_depth = F2FS_I(dir)->i_current_depth;
354 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
355 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
356 dir->i_ino, max_depth);
357 max_depth = MAX_DIR_HASH_DEPTH;
358 f2fs_i_depth_write(dir, max_depth);
359 }
360
361 for (level = 0; level < max_depth; level++) {
362 de = find_in_level(dir, level, fname, res_page, use_hash);
363 if (de || IS_ERR(*res_page))
364 break;
365 }
366
367out:
368#if IS_ENABLED(CONFIG_UNICODE)
369 if (IS_CASEFOLDED(dir) && !de && use_hash) {
370 use_hash = false;
371 goto start_find_entry;
372 }
373#endif
374 /* This is to increase the speed of f2fs_create */
375 if (!de)
376 F2FS_I(dir)->task = current;
377 return de;
378}
379
380/*
381 * Find an entry in the specified directory with the wanted name.
382 * It returns the page where the entry was found (as a parameter - res_page),
383 * and the entry itself. Page is returned mapped and unlocked.
384 * Entry is guaranteed to be valid.
385 */
386struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
387 const struct qstr *child, struct page **res_page)
388{
389 struct f2fs_dir_entry *de = NULL;
390 struct f2fs_filename fname;
391 int err;
392
393 err = f2fs_setup_filename(dir, child, 1, &fname);
394 if (err) {
395 if (err == -ENOENT)
396 *res_page = NULL;
397 else
398 *res_page = ERR_PTR(err);
399 return NULL;
400 }
401
402 de = __f2fs_find_entry(dir, &fname, res_page);
403
404 f2fs_free_filename(&fname);
405 return de;
406}
407
408struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
409{
410 return f2fs_find_entry(dir, &dotdot_name, p);
411}
412
413ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
414 struct page **page)
415{
416 ino_t res = 0;
417 struct f2fs_dir_entry *de;
418
419 de = f2fs_find_entry(dir, qstr, page);
420 if (de) {
421 res = le32_to_cpu(de->ino);
422 f2fs_put_page(*page, 0);
423 }
424
425 return res;
426}
427
428void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
429 struct page *page, struct inode *inode)
430{
431 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
432
433 lock_page(page);
434 f2fs_wait_on_page_writeback(page, type, true, true);
435 de->ino = cpu_to_le32(inode->i_ino);
436 de->file_type = fs_umode_to_ftype(inode->i_mode);
437 set_page_dirty(page);
438
439 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
440 f2fs_mark_inode_dirty_sync(dir, false);
441 f2fs_put_page(page, 1);
442}
443
444static void init_dent_inode(struct inode *dir, struct inode *inode,
445 const struct f2fs_filename *fname,
446 struct page *ipage)
447{
448 struct f2fs_inode *ri;
449
450 if (!fname) /* tmpfile case? */
451 return;
452
453 f2fs_wait_on_page_writeback(ipage, NODE, true, true);
454
455 /* copy name info. to this inode page */
456 ri = F2FS_INODE(ipage);
457 ri->i_namelen = cpu_to_le32(fname->disk_name.len);
458 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
459 if (IS_ENCRYPTED(dir)) {
460 file_set_enc_name(inode);
461 /*
462 * Roll-forward recovery doesn't have encryption keys available,
463 * so it can't compute the dirhash for encrypted+casefolded
464 * filenames. Append it to i_name if possible. Else, disable
465 * roll-forward recovery of the dentry (i.e., make fsync'ing the
466 * file force a checkpoint) by setting LOST_PINO.
467 */
468 if (IS_CASEFOLDED(dir)) {
469 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
470 F2FS_NAME_LEN)
471 put_unaligned(fname->hash, (f2fs_hash_t *)
472 &ri->i_name[fname->disk_name.len]);
473 else
474 file_lost_pino(inode);
475 }
476 }
477 set_page_dirty(ipage);
478}
479
480void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
481 struct f2fs_dentry_ptr *d)
482{
483 struct fscrypt_str dot = FSTR_INIT(".", 1);
484 struct fscrypt_str dotdot = FSTR_INIT("..", 2);
485
486 /* update dirent of "." */
487 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
488
489 /* update dirent of ".." */
490 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
491}
492
493static int make_empty_dir(struct inode *inode,
494 struct inode *parent, struct page *page)
495{
496 struct page *dentry_page;
497 struct f2fs_dentry_block *dentry_blk;
498 struct f2fs_dentry_ptr d;
499
500 if (f2fs_has_inline_dentry(inode))
501 return f2fs_make_empty_inline_dir(inode, parent, page);
502
503 dentry_page = f2fs_get_new_data_page(inode, page, 0, true);
504 if (IS_ERR(dentry_page))
505 return PTR_ERR(dentry_page);
506
507 dentry_blk = page_address(dentry_page);
508
509 make_dentry_ptr_block(NULL, &d, dentry_blk);
510 f2fs_do_make_empty_dir(inode, parent, &d);
511
512 set_page_dirty(dentry_page);
513 f2fs_put_page(dentry_page, 1);
514 return 0;
515}
516
517struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
518 const struct f2fs_filename *fname, struct page *dpage)
519{
520 struct page *page;
521 int err;
522
523 if (is_inode_flag_set(inode, FI_NEW_INODE)) {
524 page = f2fs_new_inode_page(inode);
525 if (IS_ERR(page))
526 return page;
527
528 if (S_ISDIR(inode->i_mode)) {
529 /* in order to handle error case */
530 get_page(page);
531 err = make_empty_dir(inode, dir, page);
532 if (err) {
533 lock_page(page);
534 goto put_error;
535 }
536 put_page(page);
537 }
538
539 err = f2fs_init_acl(inode, dir, page, dpage);
540 if (err)
541 goto put_error;
542
543 err = f2fs_init_security(inode, dir,
544 fname ? fname->usr_fname : NULL, page);
545 if (err)
546 goto put_error;
547
548 if (IS_ENCRYPTED(inode)) {
549 err = fscrypt_set_context(inode, page);
550 if (err)
551 goto put_error;
552 }
553 } else {
554 page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);
555 if (IS_ERR(page))
556 return page;
557 }
558
559 init_dent_inode(dir, inode, fname, page);
560
561 /*
562 * This file should be checkpointed during fsync.
563 * We lost i_pino from now on.
564 */
565 if (is_inode_flag_set(inode, FI_INC_LINK)) {
566 if (!S_ISDIR(inode->i_mode))
567 file_lost_pino(inode);
568 /*
569 * If link the tmpfile to alias through linkat path,
570 * we should remove this inode from orphan list.
571 */
572 if (inode->i_nlink == 0)
573 f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
574 f2fs_i_links_write(inode, true);
575 }
576 return page;
577
578put_error:
579 clear_nlink(inode);
580 f2fs_update_inode(inode, page);
581 f2fs_put_page(page, 1);
582 return ERR_PTR(err);
583}
584
585void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
586 unsigned int current_depth)
587{
588 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
589 if (S_ISDIR(inode->i_mode))
590 f2fs_i_links_write(dir, true);
591 clear_inode_flag(inode, FI_NEW_INODE);
592 }
593 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
594 f2fs_mark_inode_dirty_sync(dir, false);
595
596 if (F2FS_I(dir)->i_current_depth != current_depth)
597 f2fs_i_depth_write(dir, current_depth);
598
599 if (inode && is_inode_flag_set(inode, FI_INC_LINK))
600 clear_inode_flag(inode, FI_INC_LINK);
601}
602
603int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
604{
605 int bit_start = 0;
606 int zero_start, zero_end;
607next:
608 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
609 if (zero_start >= max_slots)
610 return max_slots;
611
612 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
613 if (zero_end - zero_start >= slots)
614 return zero_start;
615
616 bit_start = zero_end + 1;
617
618 if (zero_end + 1 >= max_slots)
619 return max_slots;
620 goto next;
621}
622
623bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
624 const struct f2fs_filename *fname)
625{
626 struct f2fs_dentry_ptr d;
627 unsigned int bit_pos;
628 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
629
630 make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
631
632 bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
633
634 return bit_pos < d.max;
635}
636
637void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
638 const struct fscrypt_str *name, f2fs_hash_t name_hash,
639 unsigned int bit_pos)
640{
641 struct f2fs_dir_entry *de;
642 int slots = GET_DENTRY_SLOTS(name->len);
643 int i;
644
645 de = &d->dentry[bit_pos];
646 de->hash_code = name_hash;
647 de->name_len = cpu_to_le16(name->len);
648 memcpy(d->filename[bit_pos], name->name, name->len);
649 de->ino = cpu_to_le32(ino);
650 de->file_type = fs_umode_to_ftype(mode);
651 for (i = 0; i < slots; i++) {
652 __set_bit_le(bit_pos + i, (void *)d->bitmap);
653 /* avoid wrong garbage data for readdir */
654 if (i)
655 (de + i)->name_len = 0;
656 }
657}
658
659int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
660 struct inode *inode, nid_t ino, umode_t mode)
661{
662 unsigned int bit_pos;
663 unsigned int level;
664 unsigned int current_depth;
665 unsigned long bidx, block;
666 unsigned int nbucket, nblock;
667 struct page *dentry_page = NULL;
668 struct f2fs_dentry_block *dentry_blk = NULL;
669 struct f2fs_dentry_ptr d;
670 struct page *page = NULL;
671 int slots, err = 0;
672
673 level = 0;
674 slots = GET_DENTRY_SLOTS(fname->disk_name.len);
675
676 current_depth = F2FS_I(dir)->i_current_depth;
677 if (F2FS_I(dir)->chash == fname->hash) {
678 level = F2FS_I(dir)->clevel;
679 F2FS_I(dir)->chash = 0;
680 }
681
682start:
683 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))
684 return -ENOSPC;
685
686 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
687 return -ENOSPC;
688
689 /* Increase the depth, if required */
690 if (level == current_depth)
691 ++current_depth;
692
693 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
694 nblock = bucket_blocks(level);
695
696 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
697 (le32_to_cpu(fname->hash) % nbucket));
698
699 for (block = bidx; block <= (bidx + nblock - 1); block++) {
700 dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);
701 if (IS_ERR(dentry_page))
702 return PTR_ERR(dentry_page);
703
704 dentry_blk = page_address(dentry_page);
705 bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,
706 slots, NR_DENTRY_IN_BLOCK);
707 if (bit_pos < NR_DENTRY_IN_BLOCK)
708 goto add_dentry;
709
710 f2fs_put_page(dentry_page, 1);
711 }
712
713 /* Move to next level to find the empty slot for new dentry */
714 ++level;
715 goto start;
716add_dentry:
717 f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);
718
719 if (inode) {
720 f2fs_down_write(&F2FS_I(inode)->i_sem);
721 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
722 if (IS_ERR(page)) {
723 err = PTR_ERR(page);
724 goto fail;
725 }
726 }
727
728 make_dentry_ptr_block(NULL, &d, dentry_blk);
729 f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,
730 bit_pos);
731
732 set_page_dirty(dentry_page);
733
734 if (inode) {
735 f2fs_i_pino_write(inode, dir->i_ino);
736
737 /* synchronize inode page's data from inode cache */
738 if (is_inode_flag_set(inode, FI_NEW_INODE))
739 f2fs_update_inode(inode, page);
740
741 f2fs_put_page(page, 1);
742 }
743
744 f2fs_update_parent_metadata(dir, inode, current_depth);
745fail:
746 if (inode)
747 f2fs_up_write(&F2FS_I(inode)->i_sem);
748
749 f2fs_put_page(dentry_page, 1);
750
751 return err;
752}
753
754int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
755 struct inode *inode, nid_t ino, umode_t mode)
756{
757 int err = -EAGAIN;
758
759 if (f2fs_has_inline_dentry(dir)) {
760 /*
761 * Should get i_xattr_sem to keep the lock order:
762 * i_xattr_sem -> inode_page lock used by f2fs_setxattr.
763 */
764 f2fs_down_read(&F2FS_I(dir)->i_xattr_sem);
765 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
766 f2fs_up_read(&F2FS_I(dir)->i_xattr_sem);
767 }
768 if (err == -EAGAIN)
769 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
770
771 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
772 return err;
773}
774
775/*
776 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
777 * f2fs_unlock_op().
778 */
779int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
780 struct inode *inode, nid_t ino, umode_t mode)
781{
782 struct f2fs_filename fname;
783 struct page *page = NULL;
784 struct f2fs_dir_entry *de = NULL;
785 int err;
786
787 err = f2fs_setup_filename(dir, name, 0, &fname);
788 if (err)
789 return err;
790
791 /*
792 * An immature stackable filesystem shows a race condition between lookup
793 * and create. If we have same task when doing lookup and create, it's
794 * definitely fine as expected by VFS normally. Otherwise, let's just
795 * verify on-disk dentry one more time, which guarantees filesystem
796 * consistency more.
797 */
798 if (current != F2FS_I(dir)->task) {
799 de = __f2fs_find_entry(dir, &fname, &page);
800 F2FS_I(dir)->task = NULL;
801 }
802 if (de) {
803 f2fs_put_page(page, 0);
804 err = -EEXIST;
805 } else if (IS_ERR(page)) {
806 err = PTR_ERR(page);
807 } else {
808 err = f2fs_add_dentry(dir, &fname, inode, ino, mode);
809 }
810 f2fs_free_filename(&fname);
811 return err;
812}
813
814int f2fs_do_tmpfile(struct inode *inode, struct inode *dir,
815 struct f2fs_filename *fname)
816{
817 struct page *page;
818 int err = 0;
819
820 f2fs_down_write(&F2FS_I(inode)->i_sem);
821 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
822 if (IS_ERR(page)) {
823 err = PTR_ERR(page);
824 goto fail;
825 }
826 f2fs_put_page(page, 1);
827
828 clear_inode_flag(inode, FI_NEW_INODE);
829 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
830fail:
831 f2fs_up_write(&F2FS_I(inode)->i_sem);
832 return err;
833}
834
835void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
836{
837 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
838
839 f2fs_down_write(&F2FS_I(inode)->i_sem);
840
841 if (S_ISDIR(inode->i_mode))
842 f2fs_i_links_write(dir, false);
843 inode_set_ctime_current(inode);
844
845 f2fs_i_links_write(inode, false);
846 if (S_ISDIR(inode->i_mode)) {
847 f2fs_i_links_write(inode, false);
848 f2fs_i_size_write(inode, 0);
849 }
850 f2fs_up_write(&F2FS_I(inode)->i_sem);
851
852 if (inode->i_nlink == 0)
853 f2fs_add_orphan_inode(inode);
854 else
855 f2fs_release_orphan_inode(sbi);
856}
857
858/*
859 * It only removes the dentry from the dentry page, corresponding name
860 * entry in name page does not need to be touched during deletion.
861 */
862void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
863 struct inode *dir, struct inode *inode)
864{
865 struct f2fs_dentry_block *dentry_blk;
866 unsigned int bit_pos;
867 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
868 pgoff_t index = page_folio(page)->index;
869 int i;
870
871 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
872
873 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
874 f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);
875
876 if (f2fs_has_inline_dentry(dir))
877 return f2fs_delete_inline_entry(dentry, page, dir, inode);
878
879 lock_page(page);
880 f2fs_wait_on_page_writeback(page, DATA, true, true);
881
882 dentry_blk = page_address(page);
883 bit_pos = dentry - dentry_blk->dentry;
884 for (i = 0; i < slots; i++)
885 __clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
886
887 /* Let's check and deallocate this dentry page */
888 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
889 NR_DENTRY_IN_BLOCK,
890 0);
891 set_page_dirty(page);
892
893 if (bit_pos == NR_DENTRY_IN_BLOCK &&
894 !f2fs_truncate_hole(dir, index, index + 1)) {
895 f2fs_clear_page_cache_dirty_tag(page_folio(page));
896 clear_page_dirty_for_io(page);
897 ClearPageUptodate(page);
898 clear_page_private_all(page);
899
900 inode_dec_dirty_pages(dir);
901 f2fs_remove_dirty_inode(dir);
902 }
903 f2fs_put_page(page, 1);
904
905 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
906 f2fs_mark_inode_dirty_sync(dir, false);
907
908 if (inode)
909 f2fs_drop_nlink(dir, inode);
910}
911
912bool f2fs_empty_dir(struct inode *dir)
913{
914 unsigned long bidx = 0;
915 struct page *dentry_page;
916 unsigned int bit_pos;
917 struct f2fs_dentry_block *dentry_blk;
918 unsigned long nblock = dir_blocks(dir);
919
920 if (f2fs_has_inline_dentry(dir))
921 return f2fs_empty_inline_dir(dir);
922
923 while (bidx < nblock) {
924 pgoff_t next_pgofs;
925
926 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);
927 if (IS_ERR(dentry_page)) {
928 if (PTR_ERR(dentry_page) == -ENOENT) {
929 bidx = next_pgofs;
930 continue;
931 } else {
932 return false;
933 }
934 }
935
936 dentry_blk = page_address(dentry_page);
937 if (bidx == 0)
938 bit_pos = 2;
939 else
940 bit_pos = 0;
941 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
942 NR_DENTRY_IN_BLOCK,
943 bit_pos);
944
945 f2fs_put_page(dentry_page, 0);
946
947 if (bit_pos < NR_DENTRY_IN_BLOCK)
948 return false;
949
950 bidx++;
951 }
952 return true;
953}
954
955int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
956 unsigned int start_pos, struct fscrypt_str *fstr)
957{
958 unsigned char d_type = DT_UNKNOWN;
959 unsigned int bit_pos;
960 struct f2fs_dir_entry *de = NULL;
961 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
962 struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
963 struct blk_plug plug;
964 bool readdir_ra = sbi->readdir_ra;
965 bool found_valid_dirent = false;
966 int err = 0;
967
968 bit_pos = ((unsigned long)ctx->pos % d->max);
969
970 if (readdir_ra)
971 blk_start_plug(&plug);
972
973 while (bit_pos < d->max) {
974 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
975 if (bit_pos >= d->max)
976 break;
977
978 de = &d->dentry[bit_pos];
979 if (de->name_len == 0) {
980 if (found_valid_dirent || !bit_pos) {
981 f2fs_warn_ratelimited(sbi,
982 "invalid namelen(0), ino:%u, run fsck to fix.",
983 le32_to_cpu(de->ino));
984 set_sbi_flag(sbi, SBI_NEED_FSCK);
985 }
986 bit_pos++;
987 ctx->pos = start_pos + bit_pos;
988 continue;
989 }
990
991 d_type = fs_ftype_to_dtype(de->file_type);
992
993 de_name.name = d->filename[bit_pos];
994 de_name.len = le16_to_cpu(de->name_len);
995
996 /* check memory boundary before moving forward */
997 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
998 if (unlikely(bit_pos > d->max ||
999 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
1000 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
1001 __func__, le16_to_cpu(de->name_len));
1002 set_sbi_flag(sbi, SBI_NEED_FSCK);
1003 err = -EFSCORRUPTED;
1004 f2fs_handle_error(sbi, ERROR_CORRUPTED_DIRENT);
1005 goto out;
1006 }
1007
1008 if (IS_ENCRYPTED(d->inode)) {
1009 int save_len = fstr->len;
1010
1011 err = fscrypt_fname_disk_to_usr(d->inode,
1012 (u32)le32_to_cpu(de->hash_code),
1013 0, &de_name, fstr);
1014 if (err)
1015 goto out;
1016
1017 de_name = *fstr;
1018 fstr->len = save_len;
1019 }
1020
1021 if (!dir_emit(ctx, de_name.name, de_name.len,
1022 le32_to_cpu(de->ino), d_type)) {
1023 err = 1;
1024 goto out;
1025 }
1026
1027 if (readdir_ra)
1028 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
1029
1030 ctx->pos = start_pos + bit_pos;
1031 found_valid_dirent = true;
1032 }
1033out:
1034 if (readdir_ra)
1035 blk_finish_plug(&plug);
1036 return err;
1037}
1038
1039static int f2fs_readdir(struct file *file, struct dir_context *ctx)
1040{
1041 struct inode *inode = file_inode(file);
1042 unsigned long npages = dir_blocks(inode);
1043 struct f2fs_dentry_block *dentry_blk = NULL;
1044 struct page *dentry_page = NULL;
1045 struct file_ra_state *ra = &file->f_ra;
1046 loff_t start_pos = ctx->pos;
1047 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
1048 struct f2fs_dentry_ptr d;
1049 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
1050 int err = 0;
1051
1052 if (IS_ENCRYPTED(inode)) {
1053 err = fscrypt_prepare_readdir(inode);
1054 if (err)
1055 goto out;
1056
1057 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);
1058 if (err < 0)
1059 goto out;
1060 }
1061
1062 if (f2fs_has_inline_dentry(inode)) {
1063 err = f2fs_read_inline_dir(file, ctx, &fstr);
1064 goto out_free;
1065 }
1066
1067 for (; n < npages; ctx->pos = n * NR_DENTRY_IN_BLOCK) {
1068 pgoff_t next_pgofs;
1069
1070 /* allow readdir() to be interrupted */
1071 if (fatal_signal_pending(current)) {
1072 err = -ERESTARTSYS;
1073 goto out_free;
1074 }
1075 cond_resched();
1076
1077 /* readahead for multi pages of dir */
1078 if (npages - n > 1 && !ra_has_index(ra, n))
1079 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
1080 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
1081
1082 dentry_page = f2fs_find_data_page(inode, n, &next_pgofs);
1083 if (IS_ERR(dentry_page)) {
1084 err = PTR_ERR(dentry_page);
1085 if (err == -ENOENT) {
1086 err = 0;
1087 n = next_pgofs;
1088 continue;
1089 } else {
1090 goto out_free;
1091 }
1092 }
1093
1094 dentry_blk = page_address(dentry_page);
1095
1096 make_dentry_ptr_block(inode, &d, dentry_blk);
1097
1098 err = f2fs_fill_dentries(ctx, &d,
1099 n * NR_DENTRY_IN_BLOCK, &fstr);
1100 if (err) {
1101 f2fs_put_page(dentry_page, 0);
1102 break;
1103 }
1104
1105 f2fs_put_page(dentry_page, 0);
1106
1107 n++;
1108 }
1109out_free:
1110 fscrypt_fname_free_buffer(&fstr);
1111out:
1112 trace_f2fs_readdir(inode, start_pos, ctx->pos, err);
1113 return err < 0 ? err : 0;
1114}
1115
1116const struct file_operations f2fs_dir_operations = {
1117 .llseek = generic_file_llseek,
1118 .read = generic_read_dir,
1119 .iterate_shared = f2fs_readdir,
1120 .fsync = f2fs_sync_file,
1121 .unlocked_ioctl = f2fs_ioctl,
1122#ifdef CONFIG_COMPAT
1123 .compat_ioctl = f2fs_compat_ioctl,
1124#endif
1125};