projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
f2fs: update f2fs documentation for inline dir support
[deliverable/linux.git] / fs / f2fs / dir.c
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
18 static 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
24 static 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
32 static 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
40 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
52 static 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
62 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
68 static 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
80 bool early_match_name(size_t namelen, f2fs_hash_t namehash,
81 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
92 static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
93 struct qstr *name, 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->len, namehash, de)) {
113 if (!memcmp(dentry_blk->filename[bit_pos],
114 name->name,
115 name->len)) {
116 *res_page = dentry_page;
117 goto found;
118 }
119 }
120 if (max_len > *max_slots) {
121 *max_slots = max_len;
122 max_len = 0;
123 }
124
125 /*
126 * For the most part, it should be a bug when name_len is zero.
127 * We stop here for figuring out where the bugs has occurred.
128 */
129 f2fs_bug_on(F2FS_P_SB(dentry_page), !de->name_len);
130
131 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
132 }
133
134 de = NULL;
135 kunmap(dentry_page);
136 found:
137 if (max_len > *max_slots)
138 *max_slots = max_len;
139 return de;
140 }
141
142 static struct f2fs_dir_entry *find_in_level(struct inode *dir,
143 unsigned int level, struct qstr *name,
144 f2fs_hash_t namehash, struct page **res_page)
145 {
146 int s = GET_DENTRY_SLOTS(name->len);
147 unsigned int nbucket, nblock;
148 unsigned int bidx, end_block;
149 struct page *dentry_page;
150 struct f2fs_dir_entry *de = NULL;
151 bool room = false;
152 int max_slots = 0;
153
154 f2fs_bug_on(F2FS_I_SB(dir), level > MAX_DIR_HASH_DEPTH);
155
156 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
157 nblock = bucket_blocks(level);
158
159 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
160 le32_to_cpu(namehash) % nbucket);
161 end_block = bidx + nblock;
162
163 for (; bidx < end_block; bidx++) {
164 /* no need to allocate new dentry pages to all the indices */
165 dentry_page = find_data_page(dir, bidx, true);
166 if (IS_ERR(dentry_page)) {
167 room = true;
168 continue;
169 }
170
171 de = find_in_block(dentry_page, name, &max_slots,
172 namehash, res_page);
173 if (de)
174 break;
175
176 if (max_slots >= s)
177 room = true;
178 f2fs_put_page(dentry_page, 0);
179 }
180
181 if (!de && room && F2FS_I(dir)->chash != namehash) {
182 F2FS_I(dir)->chash = namehash;
183 F2FS_I(dir)->clevel = level;
184 }
185
186 return de;
187 }
188
189 /*
190 * Find an entry in the specified directory with the wanted name.
191 * It returns the page where the entry was found (as a parameter - res_page),
192 * and the entry itself. Page is returned mapped and unlocked.
193 * Entry is guaranteed to be valid.
194 */
195 struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
196 struct qstr *child, struct page **res_page)
197 {
198 unsigned long npages = dir_blocks(dir);
199 struct f2fs_dir_entry *de = NULL;
200 f2fs_hash_t name_hash;
201 unsigned int max_depth;
202 unsigned int level;
203
204 if (f2fs_has_inline_dentry(dir))
205 return find_in_inline_dir(dir, child, res_page);
206
207 if (npages == 0)
208 return NULL;
209
210 *res_page = NULL;
211
212 name_hash = f2fs_dentry_hash(child);
213 max_depth = F2FS_I(dir)->i_current_depth;
214
215 for (level = 0; level < max_depth; level++) {
216 de = find_in_level(dir, level, child, name_hash, res_page);
217 if (de)
218 break;
219 }
220 if (!de && F2FS_I(dir)->chash != name_hash) {
221 F2FS_I(dir)->chash = name_hash;
222 F2FS_I(dir)->clevel = level - 1;
223 }
224 return de;
225 }
226
227 struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
228 {
229 struct page *page;
230 struct f2fs_dir_entry *de;
231 struct f2fs_dentry_block *dentry_blk;
232
233 if (f2fs_has_inline_dentry(dir))
234 return f2fs_parent_inline_dir(dir, p);
235
236 page = get_lock_data_page(dir, 0);
237 if (IS_ERR(page))
238 return NULL;
239
240 dentry_blk = kmap(page);
241 de = &dentry_blk->dentry[1];
242 *p = page;
243 unlock_page(page);
244 return de;
245 }
246
247 ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr)
248 {
249 ino_t res = 0;
250 struct f2fs_dir_entry *de;
251 struct page *page;
252
253 de = f2fs_find_entry(dir, qstr, &page);
254 if (de) {
255 res = le32_to_cpu(de->ino);
256 if (!f2fs_has_inline_dentry(dir))
257 kunmap(page);
258 f2fs_put_page(page, 0);
259 }
260
261 return res;
262 }
263
264 void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
265 struct page *page, struct inode *inode)
266 {
267 lock_page(page);
268 f2fs_wait_on_page_writeback(page, DATA);
269 de->ino = cpu_to_le32(inode->i_ino);
270 set_de_type(de, inode);
271 if (!f2fs_has_inline_dentry(dir))
272 kunmap(page);
273 set_page_dirty(page);
274 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
275 mark_inode_dirty(dir);
276
277 f2fs_put_page(page, 1);
278 }
279
280 static void init_dent_inode(const struct qstr *name, struct page *ipage)
281 {
282 struct f2fs_inode *ri;
283
284 f2fs_wait_on_page_writeback(ipage, NODE);
285
286 /* copy name info. to this inode page */
287 ri = F2FS_INODE(ipage);
288 ri->i_namelen = cpu_to_le32(name->len);
289 memcpy(ri->i_name, name->name, name->len);
290 set_page_dirty(ipage);
291 }
292
293 int update_dent_inode(struct inode *inode, const struct qstr *name)
294 {
295 struct page *page;
296
297 page = get_node_page(F2FS_I_SB(inode), inode->i_ino);
298 if (IS_ERR(page))
299 return PTR_ERR(page);
300
301 init_dent_inode(name, page);
302 f2fs_put_page(page, 1);
303
304 return 0;
305 }
306
307 static int make_empty_dir(struct inode *inode,
308 struct inode *parent, struct page *page)
309 {
310 struct page *dentry_page;
311 struct f2fs_dentry_block *dentry_blk;
312 struct f2fs_dir_entry *de;
313
314 if (f2fs_has_inline_dentry(inode))
315 return make_empty_inline_dir(inode, parent, page);
316
317 dentry_page = get_new_data_page(inode, page, 0, true);
318 if (IS_ERR(dentry_page))
319 return PTR_ERR(dentry_page);
320
321 dentry_blk = kmap_atomic(dentry_page);
322
323 de = &dentry_blk->dentry[0];
324 de->name_len = cpu_to_le16(1);
325 de->hash_code = 0;
326 de->ino = cpu_to_le32(inode->i_ino);
327 memcpy(dentry_blk->filename[0], ".", 1);
328 set_de_type(de, inode);
329
330 de = &dentry_blk->dentry[1];
331 de->hash_code = 0;
332 de->name_len = cpu_to_le16(2);
333 de->ino = cpu_to_le32(parent->i_ino);
334 memcpy(dentry_blk->filename[1], "..", 2);
335 set_de_type(de, inode);
336
337 test_and_set_bit_le(0, &dentry_blk->dentry_bitmap);
338 test_and_set_bit_le(1, &dentry_blk->dentry_bitmap);
339 kunmap_atomic(dentry_blk);
340
341 set_page_dirty(dentry_page);
342 f2fs_put_page(dentry_page, 1);
343 return 0;
344 }
345
346 struct page *init_inode_metadata(struct inode *inode,
347 struct inode *dir, const struct qstr *name)
348 {
349 struct page *page;
350 int err;
351
352 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
353 page = new_inode_page(inode);
354 if (IS_ERR(page))
355 return page;
356
357 if (S_ISDIR(inode->i_mode)) {
358 err = make_empty_dir(inode, dir, page);
359 if (err)
360 goto error;
361 }
362
363 err = f2fs_init_acl(inode, dir, page);
364 if (err)
365 goto put_error;
366
367 err = f2fs_init_security(inode, dir, name, page);
368 if (err)
369 goto put_error;
370 } else {
371 page = get_node_page(F2FS_I_SB(dir), inode->i_ino);
372 if (IS_ERR(page))
373 return page;
374
375 set_cold_node(inode, page);
376 }
377
378 if (name)
379 init_dent_inode(name, page);
380
381 /*
382 * This file should be checkpointed during fsync.
383 * We lost i_pino from now on.
384 */
385 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
386 file_lost_pino(inode);
387 /*
388 * If link the tmpfile to alias through linkat path,
389 * we should remove this inode from orphan list.
390 */
391 if (inode->i_nlink == 0)
392 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
393 inc_nlink(inode);
394 }
395 return page;
396
397 put_error:
398 f2fs_put_page(page, 1);
399 error:
400 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */
401 truncate_inode_pages(&inode->i_data, 0);
402 truncate_blocks(inode, 0, false);
403 remove_dirty_dir_inode(inode);
404 remove_inode_page(inode);
405 return ERR_PTR(err);
406 }
407
408 void update_parent_metadata(struct inode *dir, struct inode *inode,
409 unsigned int current_depth)
410 {
411 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
412 if (S_ISDIR(inode->i_mode)) {
413 inc_nlink(dir);
414 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
415 }
416 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
417 }
418 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
419 mark_inode_dirty(dir);
420
421 if (F2FS_I(dir)->i_current_depth != current_depth) {
422 F2FS_I(dir)->i_current_depth = current_depth;
423 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
424 }
425
426 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK))
427 clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
428 }
429
430 static int room_for_filename(struct f2fs_dentry_block *dentry_blk, int slots)
431 {
432 int bit_start = 0;
433 int zero_start, zero_end;
434 next:
435 zero_start = find_next_zero_bit_le(&dentry_blk->dentry_bitmap,
436 NR_DENTRY_IN_BLOCK,
437 bit_start);
438 if (zero_start >= NR_DENTRY_IN_BLOCK)
439 return NR_DENTRY_IN_BLOCK;
440
441 zero_end = find_next_bit_le(&dentry_blk->dentry_bitmap,
442 NR_DENTRY_IN_BLOCK,
443 zero_start);
444 if (zero_end - zero_start >= slots)
445 return zero_start;
446
447 bit_start = zero_end + 1;
448
449 if (zero_end + 1 >= NR_DENTRY_IN_BLOCK)
450 return NR_DENTRY_IN_BLOCK;
451 goto next;
452 }
453
454 /*
455 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
456 * f2fs_unlock_op().
457 */
458 int __f2fs_add_link(struct inode *dir, const struct qstr *name,
459 struct inode *inode)
460 {
461 unsigned int bit_pos;
462 unsigned int level;
463 unsigned int current_depth;
464 unsigned long bidx, block;
465 f2fs_hash_t dentry_hash;
466 struct f2fs_dir_entry *de;
467 unsigned int nbucket, nblock;
468 size_t namelen = name->len;
469 struct page *dentry_page = NULL;
470 struct f2fs_dentry_block *dentry_blk = NULL;
471 int slots = GET_DENTRY_SLOTS(namelen);
472 struct page *page;
473 int err = 0;
474 int i;
475
476 if (f2fs_has_inline_dentry(dir)) {
477 err = f2fs_add_inline_entry(dir, name, inode);
478 if (!err || err != -EAGAIN)
479 return err;
480 else
481 err = 0;
482 }
483
484 dentry_hash = f2fs_dentry_hash(name);
485 level = 0;
486 current_depth = F2FS_I(dir)->i_current_depth;
487 if (F2FS_I(dir)->chash == dentry_hash) {
488 level = F2FS_I(dir)->clevel;
489 F2FS_I(dir)->chash = 0;
490 }
491
492 start:
493 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
494 return -ENOSPC;
495
496 /* Increase the depth, if required */
497 if (level == current_depth)
498 ++current_depth;
499
500 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
501 nblock = bucket_blocks(level);
502
503 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
504 (le32_to_cpu(dentry_hash) % nbucket));
505
506 for (block = bidx; block <= (bidx + nblock - 1); block++) {
507 dentry_page = get_new_data_page(dir, NULL, block, true);
508 if (IS_ERR(dentry_page))
509 return PTR_ERR(dentry_page);
510
511 dentry_blk = kmap(dentry_page);
512 bit_pos = room_for_filename(dentry_blk, slots);
513 if (bit_pos < NR_DENTRY_IN_BLOCK)
514 goto add_dentry;
515
516 kunmap(dentry_page);
517 f2fs_put_page(dentry_page, 1);
518 }
519
520 /* Move to next level to find the empty slot for new dentry */
521 ++level;
522 goto start;
523 add_dentry:
524 f2fs_wait_on_page_writeback(dentry_page, DATA);
525
526 down_write(&F2FS_I(inode)->i_sem);
527 page = init_inode_metadata(inode, dir, name);
528 if (IS_ERR(page)) {
529 err = PTR_ERR(page);
530 goto fail;
531 }
532 de = &dentry_blk->dentry[bit_pos];
533 de->hash_code = dentry_hash;
534 de->name_len = cpu_to_le16(namelen);
535 memcpy(dentry_blk->filename[bit_pos], name->name, name->len);
536 de->ino = cpu_to_le32(inode->i_ino);
537 set_de_type(de, inode);
538 for (i = 0; i < slots; i++)
539 test_and_set_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
540 set_page_dirty(dentry_page);
541
542 /* we don't need to mark_inode_dirty now */
543 F2FS_I(inode)->i_pino = dir->i_ino;
544 update_inode(inode, page);
545 f2fs_put_page(page, 1);
546
547 update_parent_metadata(dir, inode, current_depth);
548 fail:
549 up_write(&F2FS_I(inode)->i_sem);
550
551 if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
552 update_inode_page(dir);
553 clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
554 }
555 kunmap(dentry_page);
556 f2fs_put_page(dentry_page, 1);
557 return err;
558 }
559
560 int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
561 {
562 struct page *page;
563 int err = 0;
564
565 down_write(&F2FS_I(inode)->i_sem);
566 page = init_inode_metadata(inode, dir, NULL);
567 if (IS_ERR(page)) {
568 err = PTR_ERR(page);
569 goto fail;
570 }
571 /* we don't need to mark_inode_dirty now */
572 update_inode(inode, page);
573 f2fs_put_page(page, 1);
574
575 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
576 fail:
577 up_write(&F2FS_I(inode)->i_sem);
578 return err;
579 }
580
581 void f2fs_drop_nlink(struct inode *dir, struct inode *inode, struct page *page)
582 {
583 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
584
585 down_write(&F2FS_I(inode)->i_sem);
586
587 if (S_ISDIR(inode->i_mode)) {
588 drop_nlink(dir);
589 if (page)
590 update_inode(dir, page);
591 else
592 update_inode_page(dir);
593 }
594 inode->i_ctime = CURRENT_TIME;
595
596 drop_nlink(inode);
597 if (S_ISDIR(inode->i_mode)) {
598 drop_nlink(inode);
599 i_size_write(inode, 0);
600 }
601 up_write(&F2FS_I(inode)->i_sem);
602 update_inode_page(inode);
603
604 if (inode->i_nlink == 0)
605 add_orphan_inode(sbi, inode->i_ino);
606 else
607 release_orphan_inode(sbi);
608 }
609
610 /*
611 * It only removes the dentry from the dentry page, corresponding name
612 * entry in name page does not need to be touched during deletion.
613 */
614 void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
615 struct inode *dir, struct inode *inode)
616 {
617 struct f2fs_dentry_block *dentry_blk;
618 unsigned int bit_pos;
619 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
620 int i;
621
622 if (f2fs_has_inline_dentry(dir))
623 return f2fs_delete_inline_entry(dentry, page, dir, inode);
624
625 lock_page(page);
626 f2fs_wait_on_page_writeback(page, DATA);
627
628 dentry_blk = page_address(page);
629 bit_pos = dentry - dentry_blk->dentry;
630 for (i = 0; i < slots; i++)
631 test_and_clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
632
633 /* Let's check and deallocate this dentry page */
634 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
635 NR_DENTRY_IN_BLOCK,
636 0);
637 kunmap(page); /* kunmap - pair of f2fs_find_entry */
638 set_page_dirty(page);
639
640 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
641
642 if (inode)
643 f2fs_drop_nlink(dir, inode, NULL);
644
645 if (bit_pos == NR_DENTRY_IN_BLOCK) {
646 truncate_hole(dir, page->index, page->index + 1);
647 clear_page_dirty_for_io(page);
648 ClearPageUptodate(page);
649 inode_dec_dirty_pages(dir);
650 }
651 f2fs_put_page(page, 1);
652 }
653
654 bool f2fs_empty_dir(struct inode *dir)
655 {
656 unsigned long bidx;
657 struct page *dentry_page;
658 unsigned int bit_pos;
659 struct f2fs_dentry_block *dentry_blk;
660 unsigned long nblock = dir_blocks(dir);
661
662 if (f2fs_has_inline_dentry(dir))
663 return f2fs_empty_inline_dir(dir);
664
665 for (bidx = 0; bidx < nblock; bidx++) {
666 dentry_page = get_lock_data_page(dir, bidx);
667 if (IS_ERR(dentry_page)) {
668 if (PTR_ERR(dentry_page) == -ENOENT)
669 continue;
670 else
671 return false;
672 }
673
674 dentry_blk = kmap_atomic(dentry_page);
675 if (bidx == 0)
676 bit_pos = 2;
677 else
678 bit_pos = 0;
679 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
680 NR_DENTRY_IN_BLOCK,
681 bit_pos);
682 kunmap_atomic(dentry_blk);
683
684 f2fs_put_page(dentry_page, 1);
685
686 if (bit_pos < NR_DENTRY_IN_BLOCK)
687 return false;
688 }
689 return true;
690 }
691
692 static int f2fs_readdir(struct file *file, struct dir_context *ctx)
693 {
694 struct inode *inode = file_inode(file);
695 unsigned long npages = dir_blocks(inode);
696 unsigned int bit_pos = 0;
697 struct f2fs_dentry_block *dentry_blk = NULL;
698 struct f2fs_dir_entry *de = NULL;
699 struct page *dentry_page = NULL;
700 struct file_ra_state *ra = &file->f_ra;
701 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
702 unsigned char d_type = DT_UNKNOWN;
703
704 if (f2fs_has_inline_dentry(inode))
705 return f2fs_read_inline_dir(file, ctx);
706
707 bit_pos = ((unsigned long)ctx->pos % NR_DENTRY_IN_BLOCK);
708
709 /* readahead for multi pages of dir */
710 if (npages - n > 1 && !ra_has_index(ra, n))
711 page_cache_sync_readahead(inode->i_mapping, ra, file, n,
712 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
713
714 for (; n < npages; n++) {
715 dentry_page = get_lock_data_page(inode, n);
716 if (IS_ERR(dentry_page))
717 continue;
718
719 dentry_blk = kmap(dentry_page);
720 while (bit_pos < NR_DENTRY_IN_BLOCK) {
721 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
722 NR_DENTRY_IN_BLOCK,
723 bit_pos);
724 if (bit_pos >= NR_DENTRY_IN_BLOCK)
725 break;
726
727 de = &dentry_blk->dentry[bit_pos];
728 if (de->file_type < F2FS_FT_MAX)
729 d_type = f2fs_filetype_table[de->file_type];
730 else
731 d_type = DT_UNKNOWN;
732 if (!dir_emit(ctx,
733 dentry_blk->filename[bit_pos],
734 le16_to_cpu(de->name_len),
735 le32_to_cpu(de->ino), d_type))
736 goto stop;
737
738 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
739 ctx->pos = n * NR_DENTRY_IN_BLOCK + bit_pos;
740 }
741 bit_pos = 0;
742 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
743 kunmap(dentry_page);
744 f2fs_put_page(dentry_page, 1);
745 dentry_page = NULL;
746 }
747 stop:
748 if (dentry_page && !IS_ERR(dentry_page)) {
749 kunmap(dentry_page);
750 f2fs_put_page(dentry_page, 1);
751 }
752
753 return 0;
754 }
755
756 const struct file_operations f2fs_dir_operations = {
757 .llseek = generic_file_llseek,
758 .read = generic_read_dir,
759 .iterate = f2fs_readdir,
760 .fsync = f2fs_sync_file,
761 .unlocked_ioctl = f2fs_ioctl,
762 };
Linux kernel - Deliverables
This page took 0.047667 seconds and 6 git commands to generate.