Merge tag 'for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux...
[linux-2.6-microblaze.git] / fs / ext4 / inline.c
1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3  * Copyright (c) 2012 Taobao.
4  * Written by Tao Ma <boyu.mt@taobao.com>
5  */
6
7 #include <linux/iomap.h>
8 #include <linux/fiemap.h>
9 #include <linux/iversion.h>
10
11 #include "ext4_jbd2.h"
12 #include "ext4.h"
13 #include "xattr.h"
14 #include "truncate.h"
15
16 #define EXT4_XATTR_SYSTEM_DATA  "data"
17 #define EXT4_MIN_INLINE_DATA_SIZE       ((sizeof(__le32) * EXT4_N_BLOCKS))
18 #define EXT4_INLINE_DOTDOT_OFFSET       2
19 #define EXT4_INLINE_DOTDOT_SIZE         4
20
21 static int ext4_get_inline_size(struct inode *inode)
22 {
23         if (EXT4_I(inode)->i_inline_off)
24                 return EXT4_I(inode)->i_inline_size;
25
26         return 0;
27 }
28
29 static int get_max_inline_xattr_value_size(struct inode *inode,
30                                            struct ext4_iloc *iloc)
31 {
32         struct ext4_xattr_ibody_header *header;
33         struct ext4_xattr_entry *entry;
34         struct ext4_inode *raw_inode;
35         int free, min_offs;
36
37         min_offs = EXT4_SB(inode->i_sb)->s_inode_size -
38                         EXT4_GOOD_OLD_INODE_SIZE -
39                         EXT4_I(inode)->i_extra_isize -
40                         sizeof(struct ext4_xattr_ibody_header);
41
42         /*
43          * We need to subtract another sizeof(__u32) since an in-inode xattr
44          * needs an empty 4 bytes to indicate the gap between the xattr entry
45          * and the name/value pair.
46          */
47         if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
48                 return EXT4_XATTR_SIZE(min_offs -
49                         EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA)) -
50                         EXT4_XATTR_ROUND - sizeof(__u32));
51
52         raw_inode = ext4_raw_inode(iloc);
53         header = IHDR(inode, raw_inode);
54         entry = IFIRST(header);
55
56         /* Compute min_offs. */
57         for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
58                 if (!entry->e_value_inum && entry->e_value_size) {
59                         size_t offs = le16_to_cpu(entry->e_value_offs);
60                         if (offs < min_offs)
61                                 min_offs = offs;
62                 }
63         }
64         free = min_offs -
65                 ((void *)entry - (void *)IFIRST(header)) - sizeof(__u32);
66
67         if (EXT4_I(inode)->i_inline_off) {
68                 entry = (struct ext4_xattr_entry *)
69                         ((void *)raw_inode + EXT4_I(inode)->i_inline_off);
70
71                 free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
72                 goto out;
73         }
74
75         free -= EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA));
76
77         if (free > EXT4_XATTR_ROUND)
78                 free = EXT4_XATTR_SIZE(free - EXT4_XATTR_ROUND);
79         else
80                 free = 0;
81
82 out:
83         return free;
84 }
85
86 /*
87  * Get the maximum size we now can store in an inode.
88  * If we can't find the space for a xattr entry, don't use the space
89  * of the extents since we have no space to indicate the inline data.
90  */
91 int ext4_get_max_inline_size(struct inode *inode)
92 {
93         int error, max_inline_size;
94         struct ext4_iloc iloc;
95
96         if (EXT4_I(inode)->i_extra_isize == 0)
97                 return 0;
98
99         error = ext4_get_inode_loc(inode, &iloc);
100         if (error) {
101                 ext4_error_inode_err(inode, __func__, __LINE__, 0, -error,
102                                      "can't get inode location %lu",
103                                      inode->i_ino);
104                 return 0;
105         }
106
107         down_read(&EXT4_I(inode)->xattr_sem);
108         max_inline_size = get_max_inline_xattr_value_size(inode, &iloc);
109         up_read(&EXT4_I(inode)->xattr_sem);
110
111         brelse(iloc.bh);
112
113         if (!max_inline_size)
114                 return 0;
115
116         return max_inline_size + EXT4_MIN_INLINE_DATA_SIZE;
117 }
118
119 /*
120  * this function does not take xattr_sem, which is OK because it is
121  * currently only used in a code path coming form ext4_iget, before
122  * the new inode has been unlocked
123  */
124 int ext4_find_inline_data_nolock(struct inode *inode)
125 {
126         struct ext4_xattr_ibody_find is = {
127                 .s = { .not_found = -ENODATA, },
128         };
129         struct ext4_xattr_info i = {
130                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
131                 .name = EXT4_XATTR_SYSTEM_DATA,
132         };
133         int error;
134
135         if (EXT4_I(inode)->i_extra_isize == 0)
136                 return 0;
137
138         error = ext4_get_inode_loc(inode, &is.iloc);
139         if (error)
140                 return error;
141
142         error = ext4_xattr_ibody_find(inode, &i, &is);
143         if (error)
144                 goto out;
145
146         if (!is.s.not_found) {
147                 if (is.s.here->e_value_inum) {
148                         EXT4_ERROR_INODE(inode, "inline data xattr refers "
149                                          "to an external xattr inode");
150                         error = -EFSCORRUPTED;
151                         goto out;
152                 }
153                 EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
154                                         (void *)ext4_raw_inode(&is.iloc));
155                 EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
156                                 le32_to_cpu(is.s.here->e_value_size);
157                 ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
158         }
159 out:
160         brelse(is.iloc.bh);
161         return error;
162 }
163
164 static int ext4_read_inline_data(struct inode *inode, void *buffer,
165                                  unsigned int len,
166                                  struct ext4_iloc *iloc)
167 {
168         struct ext4_xattr_entry *entry;
169         struct ext4_xattr_ibody_header *header;
170         int cp_len = 0;
171         struct ext4_inode *raw_inode;
172
173         if (!len)
174                 return 0;
175
176         BUG_ON(len > EXT4_I(inode)->i_inline_size);
177
178         cp_len = len < EXT4_MIN_INLINE_DATA_SIZE ?
179                         len : EXT4_MIN_INLINE_DATA_SIZE;
180
181         raw_inode = ext4_raw_inode(iloc);
182         memcpy(buffer, (void *)(raw_inode->i_block), cp_len);
183
184         len -= cp_len;
185         buffer += cp_len;
186
187         if (!len)
188                 goto out;
189
190         header = IHDR(inode, raw_inode);
191         entry = (struct ext4_xattr_entry *)((void *)raw_inode +
192                                             EXT4_I(inode)->i_inline_off);
193         len = min_t(unsigned int, len,
194                     (unsigned int)le32_to_cpu(entry->e_value_size));
195
196         memcpy(buffer,
197                (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs), len);
198         cp_len += len;
199
200 out:
201         return cp_len;
202 }
203
204 /*
205  * write the buffer to the inline inode.
206  * If 'create' is set, we don't need to do the extra copy in the xattr
207  * value since it is already handled by ext4_xattr_ibody_inline_set.
208  * That saves us one memcpy.
209  */
210 static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
211                                    void *buffer, loff_t pos, unsigned int len)
212 {
213         struct ext4_xattr_entry *entry;
214         struct ext4_xattr_ibody_header *header;
215         struct ext4_inode *raw_inode;
216         int cp_len = 0;
217
218         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
219                 return;
220
221         BUG_ON(!EXT4_I(inode)->i_inline_off);
222         BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
223
224         raw_inode = ext4_raw_inode(iloc);
225         buffer += pos;
226
227         if (pos < EXT4_MIN_INLINE_DATA_SIZE) {
228                 cp_len = pos + len > EXT4_MIN_INLINE_DATA_SIZE ?
229                          EXT4_MIN_INLINE_DATA_SIZE - pos : len;
230                 memcpy((void *)raw_inode->i_block + pos, buffer, cp_len);
231
232                 len -= cp_len;
233                 buffer += cp_len;
234                 pos += cp_len;
235         }
236
237         if (!len)
238                 return;
239
240         pos -= EXT4_MIN_INLINE_DATA_SIZE;
241         header = IHDR(inode, raw_inode);
242         entry = (struct ext4_xattr_entry *)((void *)raw_inode +
243                                             EXT4_I(inode)->i_inline_off);
244
245         memcpy((void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs) + pos,
246                buffer, len);
247 }
248
249 static int ext4_create_inline_data(handle_t *handle,
250                                    struct inode *inode, unsigned len)
251 {
252         int error;
253         void *value = NULL;
254         struct ext4_xattr_ibody_find is = {
255                 .s = { .not_found = -ENODATA, },
256         };
257         struct ext4_xattr_info i = {
258                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
259                 .name = EXT4_XATTR_SYSTEM_DATA,
260         };
261
262         error = ext4_get_inode_loc(inode, &is.iloc);
263         if (error)
264                 return error;
265
266         BUFFER_TRACE(is.iloc.bh, "get_write_access");
267         error = ext4_journal_get_write_access(handle, is.iloc.bh);
268         if (error)
269                 goto out;
270
271         if (len > EXT4_MIN_INLINE_DATA_SIZE) {
272                 value = EXT4_ZERO_XATTR_VALUE;
273                 len -= EXT4_MIN_INLINE_DATA_SIZE;
274         } else {
275                 value = "";
276                 len = 0;
277         }
278
279         /* Insert the xttr entry. */
280         i.value = value;
281         i.value_len = len;
282
283         error = ext4_xattr_ibody_find(inode, &i, &is);
284         if (error)
285                 goto out;
286
287         BUG_ON(!is.s.not_found);
288
289         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
290         if (error) {
291                 if (error == -ENOSPC)
292                         ext4_clear_inode_state(inode,
293                                                EXT4_STATE_MAY_INLINE_DATA);
294                 goto out;
295         }
296
297         memset((void *)ext4_raw_inode(&is.iloc)->i_block,
298                 0, EXT4_MIN_INLINE_DATA_SIZE);
299
300         EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
301                                       (void *)ext4_raw_inode(&is.iloc));
302         EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
303         ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
304         ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
305         get_bh(is.iloc.bh);
306         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
307
308 out:
309         brelse(is.iloc.bh);
310         return error;
311 }
312
313 static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
314                                    unsigned int len)
315 {
316         int error;
317         void *value = NULL;
318         struct ext4_xattr_ibody_find is = {
319                 .s = { .not_found = -ENODATA, },
320         };
321         struct ext4_xattr_info i = {
322                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
323                 .name = EXT4_XATTR_SYSTEM_DATA,
324         };
325
326         /* If the old space is ok, write the data directly. */
327         if (len <= EXT4_I(inode)->i_inline_size)
328                 return 0;
329
330         error = ext4_get_inode_loc(inode, &is.iloc);
331         if (error)
332                 return error;
333
334         error = ext4_xattr_ibody_find(inode, &i, &is);
335         if (error)
336                 goto out;
337
338         BUG_ON(is.s.not_found);
339
340         len -= EXT4_MIN_INLINE_DATA_SIZE;
341         value = kzalloc(len, GFP_NOFS);
342         if (!value) {
343                 error = -ENOMEM;
344                 goto out;
345         }
346
347         error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
348                                      value, len);
349         if (error == -ENODATA)
350                 goto out;
351
352         BUFFER_TRACE(is.iloc.bh, "get_write_access");
353         error = ext4_journal_get_write_access(handle, is.iloc.bh);
354         if (error)
355                 goto out;
356
357         /* Update the xattr entry. */
358         i.value = value;
359         i.value_len = len;
360
361         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
362         if (error)
363                 goto out;
364
365         EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
366                                       (void *)ext4_raw_inode(&is.iloc));
367         EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
368                                 le32_to_cpu(is.s.here->e_value_size);
369         ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
370         get_bh(is.iloc.bh);
371         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
372
373 out:
374         kfree(value);
375         brelse(is.iloc.bh);
376         return error;
377 }
378
379 static int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
380                                     unsigned int len)
381 {
382         int ret, size, no_expand;
383         struct ext4_inode_info *ei = EXT4_I(inode);
384
385         if (!ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
386                 return -ENOSPC;
387
388         size = ext4_get_max_inline_size(inode);
389         if (size < len)
390                 return -ENOSPC;
391
392         ext4_write_lock_xattr(inode, &no_expand);
393
394         if (ei->i_inline_off)
395                 ret = ext4_update_inline_data(handle, inode, len);
396         else
397                 ret = ext4_create_inline_data(handle, inode, len);
398
399         ext4_write_unlock_xattr(inode, &no_expand);
400         return ret;
401 }
402
403 static int ext4_destroy_inline_data_nolock(handle_t *handle,
404                                            struct inode *inode)
405 {
406         struct ext4_inode_info *ei = EXT4_I(inode);
407         struct ext4_xattr_ibody_find is = {
408                 .s = { .not_found = 0, },
409         };
410         struct ext4_xattr_info i = {
411                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
412                 .name = EXT4_XATTR_SYSTEM_DATA,
413                 .value = NULL,
414                 .value_len = 0,
415         };
416         int error;
417
418         if (!ei->i_inline_off)
419                 return 0;
420
421         error = ext4_get_inode_loc(inode, &is.iloc);
422         if (error)
423                 return error;
424
425         error = ext4_xattr_ibody_find(inode, &i, &is);
426         if (error)
427                 goto out;
428
429         BUFFER_TRACE(is.iloc.bh, "get_write_access");
430         error = ext4_journal_get_write_access(handle, is.iloc.bh);
431         if (error)
432                 goto out;
433
434         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
435         if (error)
436                 goto out;
437
438         memset((void *)ext4_raw_inode(&is.iloc)->i_block,
439                 0, EXT4_MIN_INLINE_DATA_SIZE);
440         memset(ei->i_data, 0, EXT4_MIN_INLINE_DATA_SIZE);
441
442         if (ext4_has_feature_extents(inode->i_sb)) {
443                 if (S_ISDIR(inode->i_mode) ||
444                     S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)) {
445                         ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
446                         ext4_ext_tree_init(handle, inode);
447                 }
448         }
449         ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
450
451         get_bh(is.iloc.bh);
452         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
453
454         EXT4_I(inode)->i_inline_off = 0;
455         EXT4_I(inode)->i_inline_size = 0;
456         ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
457 out:
458         brelse(is.iloc.bh);
459         if (error == -ENODATA)
460                 error = 0;
461         return error;
462 }
463
464 static int ext4_read_inline_page(struct inode *inode, struct page *page)
465 {
466         void *kaddr;
467         int ret = 0;
468         size_t len;
469         struct ext4_iloc iloc;
470
471         BUG_ON(!PageLocked(page));
472         BUG_ON(!ext4_has_inline_data(inode));
473         BUG_ON(page->index);
474
475         if (!EXT4_I(inode)->i_inline_off) {
476                 ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
477                              inode->i_ino);
478                 goto out;
479         }
480
481         ret = ext4_get_inode_loc(inode, &iloc);
482         if (ret)
483                 goto out;
484
485         len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
486         kaddr = kmap_atomic(page);
487         ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
488         flush_dcache_page(page);
489         kunmap_atomic(kaddr);
490         zero_user_segment(page, len, PAGE_SIZE);
491         SetPageUptodate(page);
492         brelse(iloc.bh);
493
494 out:
495         return ret;
496 }
497
498 int ext4_readpage_inline(struct inode *inode, struct page *page)
499 {
500         int ret = 0;
501
502         down_read(&EXT4_I(inode)->xattr_sem);
503         if (!ext4_has_inline_data(inode)) {
504                 up_read(&EXT4_I(inode)->xattr_sem);
505                 return -EAGAIN;
506         }
507
508         /*
509          * Current inline data can only exist in the 1st page,
510          * So for all the other pages, just set them uptodate.
511          */
512         if (!page->index)
513                 ret = ext4_read_inline_page(inode, page);
514         else if (!PageUptodate(page)) {
515                 zero_user_segment(page, 0, PAGE_SIZE);
516                 SetPageUptodate(page);
517         }
518
519         up_read(&EXT4_I(inode)->xattr_sem);
520
521         unlock_page(page);
522         return ret >= 0 ? 0 : ret;
523 }
524
525 static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
526                                               struct inode *inode,
527                                               unsigned flags)
528 {
529         int ret, needed_blocks, no_expand;
530         handle_t *handle = NULL;
531         int retries = 0, sem_held = 0;
532         struct page *page = NULL;
533         unsigned from, to;
534         struct ext4_iloc iloc;
535
536         if (!ext4_has_inline_data(inode)) {
537                 /*
538                  * clear the flag so that no new write
539                  * will trap here again.
540                  */
541                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
542                 return 0;
543         }
544
545         needed_blocks = ext4_writepage_trans_blocks(inode);
546
547         ret = ext4_get_inode_loc(inode, &iloc);
548         if (ret)
549                 return ret;
550
551 retry:
552         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
553         if (IS_ERR(handle)) {
554                 ret = PTR_ERR(handle);
555                 handle = NULL;
556                 goto out;
557         }
558
559         /* We cannot recurse into the filesystem as the transaction is already
560          * started */
561         flags |= AOP_FLAG_NOFS;
562
563         page = grab_cache_page_write_begin(mapping, 0, flags);
564         if (!page) {
565                 ret = -ENOMEM;
566                 goto out;
567         }
568
569         ext4_write_lock_xattr(inode, &no_expand);
570         sem_held = 1;
571         /* If some one has already done this for us, just exit. */
572         if (!ext4_has_inline_data(inode)) {
573                 ret = 0;
574                 goto out;
575         }
576
577         from = 0;
578         to = ext4_get_inline_size(inode);
579         if (!PageUptodate(page)) {
580                 ret = ext4_read_inline_page(inode, page);
581                 if (ret < 0)
582                         goto out;
583         }
584
585         ret = ext4_destroy_inline_data_nolock(handle, inode);
586         if (ret)
587                 goto out;
588
589         if (ext4_should_dioread_nolock(inode)) {
590                 ret = __block_write_begin(page, from, to,
591                                           ext4_get_block_unwritten);
592         } else
593                 ret = __block_write_begin(page, from, to, ext4_get_block);
594
595         if (!ret && ext4_should_journal_data(inode)) {
596                 ret = ext4_walk_page_buffers(handle, page_buffers(page),
597                                              from, to, NULL,
598                                              do_journal_get_write_access);
599         }
600
601         if (ret) {
602                 unlock_page(page);
603                 put_page(page);
604                 page = NULL;
605                 ext4_orphan_add(handle, inode);
606                 ext4_write_unlock_xattr(inode, &no_expand);
607                 sem_held = 0;
608                 ext4_journal_stop(handle);
609                 handle = NULL;
610                 ext4_truncate_failed_write(inode);
611                 /*
612                  * If truncate failed early the inode might
613                  * still be on the orphan list; we need to
614                  * make sure the inode is removed from the
615                  * orphan list in that case.
616                  */
617                 if (inode->i_nlink)
618                         ext4_orphan_del(NULL, inode);
619         }
620
621         if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
622                 goto retry;
623
624         if (page)
625                 block_commit_write(page, from, to);
626 out:
627         if (page) {
628                 unlock_page(page);
629                 put_page(page);
630         }
631         if (sem_held)
632                 ext4_write_unlock_xattr(inode, &no_expand);
633         if (handle)
634                 ext4_journal_stop(handle);
635         brelse(iloc.bh);
636         return ret;
637 }
638
639 /*
640  * Try to write data in the inode.
641  * If the inode has inline data, check whether the new write can be
642  * in the inode also. If not, create the page the handle, move the data
643  * to the page make it update and let the later codes create extent for it.
644  */
645 int ext4_try_to_write_inline_data(struct address_space *mapping,
646                                   struct inode *inode,
647                                   loff_t pos, unsigned len,
648                                   unsigned flags,
649                                   struct page **pagep)
650 {
651         int ret;
652         handle_t *handle;
653         struct page *page;
654         struct ext4_iloc iloc;
655
656         if (pos + len > ext4_get_max_inline_size(inode))
657                 goto convert;
658
659         ret = ext4_get_inode_loc(inode, &iloc);
660         if (ret)
661                 return ret;
662
663         /*
664          * The possible write could happen in the inode,
665          * so try to reserve the space in inode first.
666          */
667         handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
668         if (IS_ERR(handle)) {
669                 ret = PTR_ERR(handle);
670                 handle = NULL;
671                 goto out;
672         }
673
674         ret = ext4_prepare_inline_data(handle, inode, pos + len);
675         if (ret && ret != -ENOSPC)
676                 goto out;
677
678         /* We don't have space in inline inode, so convert it to extent. */
679         if (ret == -ENOSPC) {
680                 ext4_journal_stop(handle);
681                 brelse(iloc.bh);
682                 goto convert;
683         }
684
685         ret = ext4_journal_get_write_access(handle, iloc.bh);
686         if (ret)
687                 goto out;
688
689         flags |= AOP_FLAG_NOFS;
690
691         page = grab_cache_page_write_begin(mapping, 0, flags);
692         if (!page) {
693                 ret = -ENOMEM;
694                 goto out;
695         }
696
697         *pagep = page;
698         down_read(&EXT4_I(inode)->xattr_sem);
699         if (!ext4_has_inline_data(inode)) {
700                 ret = 0;
701                 unlock_page(page);
702                 put_page(page);
703                 goto out_up_read;
704         }
705
706         if (!PageUptodate(page)) {
707                 ret = ext4_read_inline_page(inode, page);
708                 if (ret < 0) {
709                         unlock_page(page);
710                         put_page(page);
711                         goto out_up_read;
712                 }
713         }
714
715         ret = 1;
716         handle = NULL;
717 out_up_read:
718         up_read(&EXT4_I(inode)->xattr_sem);
719 out:
720         if (handle && (ret != 1))
721                 ext4_journal_stop(handle);
722         brelse(iloc.bh);
723         return ret;
724 convert:
725         return ext4_convert_inline_data_to_extent(mapping,
726                                                   inode, flags);
727 }
728
729 int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
730                                unsigned copied, struct page *page)
731 {
732         int ret, no_expand;
733         void *kaddr;
734         struct ext4_iloc iloc;
735
736         if (unlikely(copied < len)) {
737                 if (!PageUptodate(page)) {
738                         copied = 0;
739                         goto out;
740                 }
741         }
742
743         ret = ext4_get_inode_loc(inode, &iloc);
744         if (ret) {
745                 ext4_std_error(inode->i_sb, ret);
746                 copied = 0;
747                 goto out;
748         }
749
750         ext4_write_lock_xattr(inode, &no_expand);
751         BUG_ON(!ext4_has_inline_data(inode));
752
753         kaddr = kmap_atomic(page);
754         ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
755         kunmap_atomic(kaddr);
756         SetPageUptodate(page);
757         /* clear page dirty so that writepages wouldn't work for us. */
758         ClearPageDirty(page);
759
760         ext4_write_unlock_xattr(inode, &no_expand);
761         brelse(iloc.bh);
762         mark_inode_dirty(inode);
763 out:
764         return copied;
765 }
766
767 struct buffer_head *
768 ext4_journalled_write_inline_data(struct inode *inode,
769                                   unsigned len,
770                                   struct page *page)
771 {
772         int ret, no_expand;
773         void *kaddr;
774         struct ext4_iloc iloc;
775
776         ret = ext4_get_inode_loc(inode, &iloc);
777         if (ret) {
778                 ext4_std_error(inode->i_sb, ret);
779                 return NULL;
780         }
781
782         ext4_write_lock_xattr(inode, &no_expand);
783         kaddr = kmap_atomic(page);
784         ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
785         kunmap_atomic(kaddr);
786         ext4_write_unlock_xattr(inode, &no_expand);
787
788         return iloc.bh;
789 }
790
791 /*
792  * Try to make the page cache and handle ready for the inline data case.
793  * We can call this function in 2 cases:
794  * 1. The inode is created and the first write exceeds inline size. We can
795  *    clear the inode state safely.
796  * 2. The inode has inline data, then we need to read the data, make it
797  *    update and dirty so that ext4_da_writepages can handle it. We don't
798  *    need to start the journal since the file's metatdata isn't changed now.
799  */
800 static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
801                                                  struct inode *inode,
802                                                  unsigned flags,
803                                                  void **fsdata)
804 {
805         int ret = 0, inline_size;
806         struct page *page;
807
808         page = grab_cache_page_write_begin(mapping, 0, flags);
809         if (!page)
810                 return -ENOMEM;
811
812         down_read(&EXT4_I(inode)->xattr_sem);
813         if (!ext4_has_inline_data(inode)) {
814                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
815                 goto out;
816         }
817
818         inline_size = ext4_get_inline_size(inode);
819
820         if (!PageUptodate(page)) {
821                 ret = ext4_read_inline_page(inode, page);
822                 if (ret < 0)
823                         goto out;
824         }
825
826         ret = __block_write_begin(page, 0, inline_size,
827                                   ext4_da_get_block_prep);
828         if (ret) {
829                 up_read(&EXT4_I(inode)->xattr_sem);
830                 unlock_page(page);
831                 put_page(page);
832                 ext4_truncate_failed_write(inode);
833                 return ret;
834         }
835
836         SetPageDirty(page);
837         SetPageUptodate(page);
838         ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
839         *fsdata = (void *)CONVERT_INLINE_DATA;
840
841 out:
842         up_read(&EXT4_I(inode)->xattr_sem);
843         if (page) {
844                 unlock_page(page);
845                 put_page(page);
846         }
847         return ret;
848 }
849
850 /*
851  * Prepare the write for the inline data.
852  * If the data can be written into the inode, we just read
853  * the page and make it uptodate, and start the journal.
854  * Otherwise read the page, makes it dirty so that it can be
855  * handle in writepages(the i_disksize update is left to the
856  * normal ext4_da_write_end).
857  */
858 int ext4_da_write_inline_data_begin(struct address_space *mapping,
859                                     struct inode *inode,
860                                     loff_t pos, unsigned len,
861                                     unsigned flags,
862                                     struct page **pagep,
863                                     void **fsdata)
864 {
865         int ret, inline_size;
866         handle_t *handle;
867         struct page *page;
868         struct ext4_iloc iloc;
869         int retries = 0;
870
871         ret = ext4_get_inode_loc(inode, &iloc);
872         if (ret)
873                 return ret;
874
875 retry_journal:
876         handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
877         if (IS_ERR(handle)) {
878                 ret = PTR_ERR(handle);
879                 goto out;
880         }
881
882         inline_size = ext4_get_max_inline_size(inode);
883
884         ret = -ENOSPC;
885         if (inline_size >= pos + len) {
886                 ret = ext4_prepare_inline_data(handle, inode, pos + len);
887                 if (ret && ret != -ENOSPC)
888                         goto out_journal;
889         }
890
891         /*
892          * We cannot recurse into the filesystem as the transaction
893          * is already started.
894          */
895         flags |= AOP_FLAG_NOFS;
896
897         if (ret == -ENOSPC) {
898                 ext4_journal_stop(handle);
899                 ret = ext4_da_convert_inline_data_to_extent(mapping,
900                                                             inode,
901                                                             flags,
902                                                             fsdata);
903                 if (ret == -ENOSPC &&
904                     ext4_should_retry_alloc(inode->i_sb, &retries))
905                         goto retry_journal;
906                 goto out;
907         }
908
909         page = grab_cache_page_write_begin(mapping, 0, flags);
910         if (!page) {
911                 ret = -ENOMEM;
912                 goto out_journal;
913         }
914
915         down_read(&EXT4_I(inode)->xattr_sem);
916         if (!ext4_has_inline_data(inode)) {
917                 ret = 0;
918                 goto out_release_page;
919         }
920
921         if (!PageUptodate(page)) {
922                 ret = ext4_read_inline_page(inode, page);
923                 if (ret < 0)
924                         goto out_release_page;
925         }
926         ret = ext4_journal_get_write_access(handle, iloc.bh);
927         if (ret)
928                 goto out_release_page;
929
930         up_read(&EXT4_I(inode)->xattr_sem);
931         *pagep = page;
932         brelse(iloc.bh);
933         return 1;
934 out_release_page:
935         up_read(&EXT4_I(inode)->xattr_sem);
936         unlock_page(page);
937         put_page(page);
938 out_journal:
939         ext4_journal_stop(handle);
940 out:
941         brelse(iloc.bh);
942         return ret;
943 }
944
945 int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
946                                   unsigned len, unsigned copied,
947                                   struct page *page)
948 {
949         int ret;
950
951         ret = ext4_write_inline_data_end(inode, pos, len, copied, page);
952         if (ret < 0) {
953                 unlock_page(page);
954                 put_page(page);
955                 return ret;
956         }
957         copied = ret;
958
959         /*
960          * No need to use i_size_read() here, the i_size
961          * cannot change under us because we hold i_mutex.
962          *
963          * But it's important to update i_size while still holding page lock:
964          * page writeout could otherwise come in and zero beyond i_size.
965          */
966         if (pos+copied > inode->i_size)
967                 i_size_write(inode, pos+copied);
968         unlock_page(page);
969         put_page(page);
970
971         /*
972          * Don't mark the inode dirty under page lock. First, it unnecessarily
973          * makes the holding time of page lock longer. Second, it forces lock
974          * ordering of page lock and transaction start for journaling
975          * filesystems.
976          */
977         mark_inode_dirty(inode);
978
979         return copied;
980 }
981
982 #ifdef INLINE_DIR_DEBUG
983 void ext4_show_inline_dir(struct inode *dir, struct buffer_head *bh,
984                           void *inline_start, int inline_size)
985 {
986         int offset;
987         unsigned short de_len;
988         struct ext4_dir_entry_2 *de = inline_start;
989         void *dlimit = inline_start + inline_size;
990
991         trace_printk("inode %lu\n", dir->i_ino);
992         offset = 0;
993         while ((void *)de < dlimit) {
994                 de_len = ext4_rec_len_from_disk(de->rec_len, inline_size);
995                 trace_printk("de: off %u rlen %u name %.*s nlen %u ino %u\n",
996                              offset, de_len, de->name_len, de->name,
997                              de->name_len, le32_to_cpu(de->inode));
998                 if (ext4_check_dir_entry(dir, NULL, de, bh,
999                                          inline_start, inline_size, offset))
1000                         BUG();
1001
1002                 offset += de_len;
1003                 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1004         }
1005 }
1006 #else
1007 #define ext4_show_inline_dir(dir, bh, inline_start, inline_size)
1008 #endif
1009
1010 /*
1011  * Add a new entry into a inline dir.
1012  * It will return -ENOSPC if no space is available, and -EIO
1013  * and -EEXIST if directory entry already exists.
1014  */
1015 static int ext4_add_dirent_to_inline(handle_t *handle,
1016                                      struct ext4_filename *fname,
1017                                      struct inode *dir,
1018                                      struct inode *inode,
1019                                      struct ext4_iloc *iloc,
1020                                      void *inline_start, int inline_size)
1021 {
1022         int             err;
1023         struct ext4_dir_entry_2 *de;
1024
1025         err = ext4_find_dest_de(dir, inode, iloc->bh, inline_start,
1026                                 inline_size, fname, &de);
1027         if (err)
1028                 return err;
1029
1030         BUFFER_TRACE(iloc->bh, "get_write_access");
1031         err = ext4_journal_get_write_access(handle, iloc->bh);
1032         if (err)
1033                 return err;
1034         ext4_insert_dentry(inode, de, inline_size, fname);
1035
1036         ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
1037
1038         /*
1039          * XXX shouldn't update any times until successful
1040          * completion of syscall, but too many callers depend
1041          * on this.
1042          *
1043          * XXX similarly, too many callers depend on
1044          * ext4_new_inode() setting the times, but error
1045          * recovery deletes the inode, so the worst that can
1046          * happen is that the times are slightly out of date
1047          * and/or different from the directory change time.
1048          */
1049         dir->i_mtime = dir->i_ctime = current_time(dir);
1050         ext4_update_dx_flag(dir);
1051         inode_inc_iversion(dir);
1052         return 1;
1053 }
1054
1055 static void *ext4_get_inline_xattr_pos(struct inode *inode,
1056                                        struct ext4_iloc *iloc)
1057 {
1058         struct ext4_xattr_entry *entry;
1059         struct ext4_xattr_ibody_header *header;
1060
1061         BUG_ON(!EXT4_I(inode)->i_inline_off);
1062
1063         header = IHDR(inode, ext4_raw_inode(iloc));
1064         entry = (struct ext4_xattr_entry *)((void *)ext4_raw_inode(iloc) +
1065                                             EXT4_I(inode)->i_inline_off);
1066
1067         return (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs);
1068 }
1069
1070 /* Set the final de to cover the whole block. */
1071 static void ext4_update_final_de(void *de_buf, int old_size, int new_size)
1072 {
1073         struct ext4_dir_entry_2 *de, *prev_de;
1074         void *limit;
1075         int de_len;
1076
1077         de = (struct ext4_dir_entry_2 *)de_buf;
1078         if (old_size) {
1079                 limit = de_buf + old_size;
1080                 do {
1081                         prev_de = de;
1082                         de_len = ext4_rec_len_from_disk(de->rec_len, old_size);
1083                         de_buf += de_len;
1084                         de = (struct ext4_dir_entry_2 *)de_buf;
1085                 } while (de_buf < limit);
1086
1087                 prev_de->rec_len = ext4_rec_len_to_disk(de_len + new_size -
1088                                                         old_size, new_size);
1089         } else {
1090                 /* this is just created, so create an empty entry. */
1091                 de->inode = 0;
1092                 de->rec_len = ext4_rec_len_to_disk(new_size, new_size);
1093         }
1094 }
1095
1096 static int ext4_update_inline_dir(handle_t *handle, struct inode *dir,
1097                                   struct ext4_iloc *iloc)
1098 {
1099         int ret;
1100         int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
1101         int new_size = get_max_inline_xattr_value_size(dir, iloc);
1102
1103         if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
1104                 return -ENOSPC;
1105
1106         ret = ext4_update_inline_data(handle, dir,
1107                                       new_size + EXT4_MIN_INLINE_DATA_SIZE);
1108         if (ret)
1109                 return ret;
1110
1111         ext4_update_final_de(ext4_get_inline_xattr_pos(dir, iloc), old_size,
1112                              EXT4_I(dir)->i_inline_size -
1113                                                 EXT4_MIN_INLINE_DATA_SIZE);
1114         dir->i_size = EXT4_I(dir)->i_disksize = EXT4_I(dir)->i_inline_size;
1115         return 0;
1116 }
1117
1118 static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
1119                                      struct ext4_iloc *iloc,
1120                                      void *buf, int inline_size)
1121 {
1122         ext4_create_inline_data(handle, inode, inline_size);
1123         ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
1124         ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1125 }
1126
1127 static int ext4_finish_convert_inline_dir(handle_t *handle,
1128                                           struct inode *inode,
1129                                           struct buffer_head *dir_block,
1130                                           void *buf,
1131                                           int inline_size)
1132 {
1133         int err, csum_size = 0, header_size = 0;
1134         struct ext4_dir_entry_2 *de;
1135         void *target = dir_block->b_data;
1136
1137         /*
1138          * First create "." and ".." and then copy the dir information
1139          * back to the block.
1140          */
1141         de = (struct ext4_dir_entry_2 *)target;
1142         de = ext4_init_dot_dotdot(inode, de,
1143                 inode->i_sb->s_blocksize, csum_size,
1144                 le32_to_cpu(((struct ext4_dir_entry_2 *)buf)->inode), 1);
1145         header_size = (void *)de - target;
1146
1147         memcpy((void *)de, buf + EXT4_INLINE_DOTDOT_SIZE,
1148                 inline_size - EXT4_INLINE_DOTDOT_SIZE);
1149
1150         if (ext4_has_metadata_csum(inode->i_sb))
1151                 csum_size = sizeof(struct ext4_dir_entry_tail);
1152
1153         inode->i_size = inode->i_sb->s_blocksize;
1154         i_size_write(inode, inode->i_sb->s_blocksize);
1155         EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1156         ext4_update_final_de(dir_block->b_data,
1157                         inline_size - EXT4_INLINE_DOTDOT_SIZE + header_size,
1158                         inode->i_sb->s_blocksize - csum_size);
1159
1160         if (csum_size)
1161                 ext4_initialize_dirent_tail(dir_block,
1162                                             inode->i_sb->s_blocksize);
1163         set_buffer_uptodate(dir_block);
1164         err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
1165         if (err)
1166                 return err;
1167         set_buffer_verified(dir_block);
1168         return ext4_mark_inode_dirty(handle, inode);
1169 }
1170
1171 static int ext4_convert_inline_data_nolock(handle_t *handle,
1172                                            struct inode *inode,
1173                                            struct ext4_iloc *iloc)
1174 {
1175         int error;
1176         void *buf = NULL;
1177         struct buffer_head *data_bh = NULL;
1178         struct ext4_map_blocks map;
1179         int inline_size;
1180
1181         inline_size = ext4_get_inline_size(inode);
1182         buf = kmalloc(inline_size, GFP_NOFS);
1183         if (!buf) {
1184                 error = -ENOMEM;
1185                 goto out;
1186         }
1187
1188         error = ext4_read_inline_data(inode, buf, inline_size, iloc);
1189         if (error < 0)
1190                 goto out;
1191
1192         /*
1193          * Make sure the inline directory entries pass checks before we try to
1194          * convert them, so that we avoid touching stuff that needs fsck.
1195          */
1196         if (S_ISDIR(inode->i_mode)) {
1197                 error = ext4_check_all_de(inode, iloc->bh,
1198                                         buf + EXT4_INLINE_DOTDOT_SIZE,
1199                                         inline_size - EXT4_INLINE_DOTDOT_SIZE);
1200                 if (error)
1201                         goto out;
1202         }
1203
1204         error = ext4_destroy_inline_data_nolock(handle, inode);
1205         if (error)
1206                 goto out;
1207
1208         map.m_lblk = 0;
1209         map.m_len = 1;
1210         map.m_flags = 0;
1211         error = ext4_map_blocks(handle, inode, &map, EXT4_GET_BLOCKS_CREATE);
1212         if (error < 0)
1213                 goto out_restore;
1214         if (!(map.m_flags & EXT4_MAP_MAPPED)) {
1215                 error = -EIO;
1216                 goto out_restore;
1217         }
1218
1219         data_bh = sb_getblk(inode->i_sb, map.m_pblk);
1220         if (!data_bh) {
1221                 error = -ENOMEM;
1222                 goto out_restore;
1223         }
1224
1225         lock_buffer(data_bh);
1226         error = ext4_journal_get_create_access(handle, data_bh);
1227         if (error) {
1228                 unlock_buffer(data_bh);
1229                 error = -EIO;
1230                 goto out_restore;
1231         }
1232         memset(data_bh->b_data, 0, inode->i_sb->s_blocksize);
1233
1234         if (!S_ISDIR(inode->i_mode)) {
1235                 memcpy(data_bh->b_data, buf, inline_size);
1236                 set_buffer_uptodate(data_bh);
1237                 error = ext4_handle_dirty_metadata(handle,
1238                                                    inode, data_bh);
1239         } else {
1240                 error = ext4_finish_convert_inline_dir(handle, inode, data_bh,
1241                                                        buf, inline_size);
1242         }
1243
1244         unlock_buffer(data_bh);
1245 out_restore:
1246         if (error)
1247                 ext4_restore_inline_data(handle, inode, iloc, buf, inline_size);
1248
1249 out:
1250         brelse(data_bh);
1251         kfree(buf);
1252         return error;
1253 }
1254
1255 /*
1256  * Try to add the new entry to the inline data.
1257  * If succeeds, return 0. If not, extended the inline dir and copied data to
1258  * the new created block.
1259  */
1260 int ext4_try_add_inline_entry(handle_t *handle, struct ext4_filename *fname,
1261                               struct inode *dir, struct inode *inode)
1262 {
1263         int ret, ret2, inline_size, no_expand;
1264         void *inline_start;
1265         struct ext4_iloc iloc;
1266
1267         ret = ext4_get_inode_loc(dir, &iloc);
1268         if (ret)
1269                 return ret;
1270
1271         ext4_write_lock_xattr(dir, &no_expand);
1272         if (!ext4_has_inline_data(dir))
1273                 goto out;
1274
1275         inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1276                                                  EXT4_INLINE_DOTDOT_SIZE;
1277         inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1278
1279         ret = ext4_add_dirent_to_inline(handle, fname, dir, inode, &iloc,
1280                                         inline_start, inline_size);
1281         if (ret != -ENOSPC)
1282                 goto out;
1283
1284         /* check whether it can be inserted to inline xattr space. */
1285         inline_size = EXT4_I(dir)->i_inline_size -
1286                         EXT4_MIN_INLINE_DATA_SIZE;
1287         if (!inline_size) {
1288                 /* Try to use the xattr space.*/
1289                 ret = ext4_update_inline_dir(handle, dir, &iloc);
1290                 if (ret && ret != -ENOSPC)
1291                         goto out;
1292
1293                 inline_size = EXT4_I(dir)->i_inline_size -
1294                                 EXT4_MIN_INLINE_DATA_SIZE;
1295         }
1296
1297         if (inline_size) {
1298                 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1299
1300                 ret = ext4_add_dirent_to_inline(handle, fname, dir,
1301                                                 inode, &iloc, inline_start,
1302                                                 inline_size);
1303
1304                 if (ret != -ENOSPC)
1305                         goto out;
1306         }
1307
1308         /*
1309          * The inline space is filled up, so create a new block for it.
1310          * As the extent tree will be created, we have to save the inline
1311          * dir first.
1312          */
1313         ret = ext4_convert_inline_data_nolock(handle, dir, &iloc);
1314
1315 out:
1316         ext4_write_unlock_xattr(dir, &no_expand);
1317         ret2 = ext4_mark_inode_dirty(handle, dir);
1318         if (unlikely(ret2 && !ret))
1319                 ret = ret2;
1320         brelse(iloc.bh);
1321         return ret;
1322 }
1323
1324 /*
1325  * This function fills a red-black tree with information from an
1326  * inlined dir.  It returns the number directory entries loaded
1327  * into the tree.  If there is an error it is returned in err.
1328  */
1329 int ext4_inlinedir_to_tree(struct file *dir_file,
1330                            struct inode *dir, ext4_lblk_t block,
1331                            struct dx_hash_info *hinfo,
1332                            __u32 start_hash, __u32 start_minor_hash,
1333                            int *has_inline_data)
1334 {
1335         int err = 0, count = 0;
1336         unsigned int parent_ino;
1337         int pos;
1338         struct ext4_dir_entry_2 *de;
1339         struct inode *inode = file_inode(dir_file);
1340         int ret, inline_size = 0;
1341         struct ext4_iloc iloc;
1342         void *dir_buf = NULL;
1343         struct ext4_dir_entry_2 fake;
1344         struct fscrypt_str tmp_str;
1345
1346         ret = ext4_get_inode_loc(inode, &iloc);
1347         if (ret)
1348                 return ret;
1349
1350         down_read(&EXT4_I(inode)->xattr_sem);
1351         if (!ext4_has_inline_data(inode)) {
1352                 up_read(&EXT4_I(inode)->xattr_sem);
1353                 *has_inline_data = 0;
1354                 goto out;
1355         }
1356
1357         inline_size = ext4_get_inline_size(inode);
1358         dir_buf = kmalloc(inline_size, GFP_NOFS);
1359         if (!dir_buf) {
1360                 ret = -ENOMEM;
1361                 up_read(&EXT4_I(inode)->xattr_sem);
1362                 goto out;
1363         }
1364
1365         ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
1366         up_read(&EXT4_I(inode)->xattr_sem);
1367         if (ret < 0)
1368                 goto out;
1369
1370         pos = 0;
1371         parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
1372         while (pos < inline_size) {
1373                 /*
1374                  * As inlined dir doesn't store any information about '.' and
1375                  * only the inode number of '..' is stored, we have to handle
1376                  * them differently.
1377                  */
1378                 if (pos == 0) {
1379                         fake.inode = cpu_to_le32(inode->i_ino);
1380                         fake.name_len = 1;
1381                         strcpy(fake.name, ".");
1382                         fake.rec_len = ext4_rec_len_to_disk(
1383                                                 EXT4_DIR_REC_LEN(fake.name_len),
1384                                                 inline_size);
1385                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
1386                         de = &fake;
1387                         pos = EXT4_INLINE_DOTDOT_OFFSET;
1388                 } else if (pos == EXT4_INLINE_DOTDOT_OFFSET) {
1389                         fake.inode = cpu_to_le32(parent_ino);
1390                         fake.name_len = 2;
1391                         strcpy(fake.name, "..");
1392                         fake.rec_len = ext4_rec_len_to_disk(
1393                                                 EXT4_DIR_REC_LEN(fake.name_len),
1394                                                 inline_size);
1395                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
1396                         de = &fake;
1397                         pos = EXT4_INLINE_DOTDOT_SIZE;
1398                 } else {
1399                         de = (struct ext4_dir_entry_2 *)(dir_buf + pos);
1400                         pos += ext4_rec_len_from_disk(de->rec_len, inline_size);
1401                         if (ext4_check_dir_entry(inode, dir_file, de,
1402                                          iloc.bh, dir_buf,
1403                                          inline_size, pos)) {
1404                                 ret = count;
1405                                 goto out;
1406                         }
1407                 }
1408
1409                 ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
1410                 if ((hinfo->hash < start_hash) ||
1411                     ((hinfo->hash == start_hash) &&
1412                      (hinfo->minor_hash < start_minor_hash)))
1413                         continue;
1414                 if (de->inode == 0)
1415                         continue;
1416                 tmp_str.name = de->name;
1417                 tmp_str.len = de->name_len;
1418                 err = ext4_htree_store_dirent(dir_file, hinfo->hash,
1419                                               hinfo->minor_hash, de, &tmp_str);
1420                 if (err) {
1421                         ret = err;
1422                         goto out;
1423                 }
1424                 count++;
1425         }
1426         ret = count;
1427 out:
1428         kfree(dir_buf);
1429         brelse(iloc.bh);
1430         return ret;
1431 }
1432
1433 /*
1434  * So this function is called when the volume is mkfsed with
1435  * dir_index disabled. In order to keep f_pos persistent
1436  * after we convert from an inlined dir to a blocked based,
1437  * we just pretend that we are a normal dir and return the
1438  * offset as if '.' and '..' really take place.
1439  *
1440  */
1441 int ext4_read_inline_dir(struct file *file,
1442                          struct dir_context *ctx,
1443                          int *has_inline_data)
1444 {
1445         unsigned int offset, parent_ino;
1446         int i;
1447         struct ext4_dir_entry_2 *de;
1448         struct super_block *sb;
1449         struct inode *inode = file_inode(file);
1450         int ret, inline_size = 0;
1451         struct ext4_iloc iloc;
1452         void *dir_buf = NULL;
1453         int dotdot_offset, dotdot_size, extra_offset, extra_size;
1454
1455         ret = ext4_get_inode_loc(inode, &iloc);
1456         if (ret)
1457                 return ret;
1458
1459         down_read(&EXT4_I(inode)->xattr_sem);
1460         if (!ext4_has_inline_data(inode)) {
1461                 up_read(&EXT4_I(inode)->xattr_sem);
1462                 *has_inline_data = 0;
1463                 goto out;
1464         }
1465
1466         inline_size = ext4_get_inline_size(inode);
1467         dir_buf = kmalloc(inline_size, GFP_NOFS);
1468         if (!dir_buf) {
1469                 ret = -ENOMEM;
1470                 up_read(&EXT4_I(inode)->xattr_sem);
1471                 goto out;
1472         }
1473
1474         ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
1475         up_read(&EXT4_I(inode)->xattr_sem);
1476         if (ret < 0)
1477                 goto out;
1478
1479         ret = 0;
1480         sb = inode->i_sb;
1481         parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
1482         offset = ctx->pos;
1483
1484         /*
1485          * dotdot_offset and dotdot_size is the real offset and
1486          * size for ".." and "." if the dir is block based while
1487          * the real size for them are only EXT4_INLINE_DOTDOT_SIZE.
1488          * So we will use extra_offset and extra_size to indicate them
1489          * during the inline dir iteration.
1490          */
1491         dotdot_offset = EXT4_DIR_REC_LEN(1);
1492         dotdot_size = dotdot_offset + EXT4_DIR_REC_LEN(2);
1493         extra_offset = dotdot_size - EXT4_INLINE_DOTDOT_SIZE;
1494         extra_size = extra_offset + inline_size;
1495
1496         /*
1497          * If the version has changed since the last call to
1498          * readdir(2), then we might be pointing to an invalid
1499          * dirent right now.  Scan from the start of the inline
1500          * dir to make sure.
1501          */
1502         if (!inode_eq_iversion(inode, file->f_version)) {
1503                 for (i = 0; i < extra_size && i < offset;) {
1504                         /*
1505                          * "." is with offset 0 and
1506                          * ".." is dotdot_offset.
1507                          */
1508                         if (!i) {
1509                                 i = dotdot_offset;
1510                                 continue;
1511                         } else if (i == dotdot_offset) {
1512                                 i = dotdot_size;
1513                                 continue;
1514                         }
1515                         /* for other entry, the real offset in
1516                          * the buf has to be tuned accordingly.
1517                          */
1518                         de = (struct ext4_dir_entry_2 *)
1519                                 (dir_buf + i - extra_offset);
1520                         /* It's too expensive to do a full
1521                          * dirent test each time round this
1522                          * loop, but we do have to test at
1523                          * least that it is non-zero.  A
1524                          * failure will be detected in the
1525                          * dirent test below. */
1526                         if (ext4_rec_len_from_disk(de->rec_len, extra_size)
1527                                 < EXT4_DIR_REC_LEN(1))
1528                                 break;
1529                         i += ext4_rec_len_from_disk(de->rec_len,
1530                                                     extra_size);
1531                 }
1532                 offset = i;
1533                 ctx->pos = offset;
1534                 file->f_version = inode_query_iversion(inode);
1535         }
1536
1537         while (ctx->pos < extra_size) {
1538                 if (ctx->pos == 0) {
1539                         if (!dir_emit(ctx, ".", 1, inode->i_ino, DT_DIR))
1540                                 goto out;
1541                         ctx->pos = dotdot_offset;
1542                         continue;
1543                 }
1544
1545                 if (ctx->pos == dotdot_offset) {
1546                         if (!dir_emit(ctx, "..", 2, parent_ino, DT_DIR))
1547                                 goto out;
1548                         ctx->pos = dotdot_size;
1549                         continue;
1550                 }
1551
1552                 de = (struct ext4_dir_entry_2 *)
1553                         (dir_buf + ctx->pos - extra_offset);
1554                 if (ext4_check_dir_entry(inode, file, de, iloc.bh, dir_buf,
1555                                          extra_size, ctx->pos))
1556                         goto out;
1557                 if (le32_to_cpu(de->inode)) {
1558                         if (!dir_emit(ctx, de->name, de->name_len,
1559                                       le32_to_cpu(de->inode),
1560                                       get_dtype(sb, de->file_type)))
1561                                 goto out;
1562                 }
1563                 ctx->pos += ext4_rec_len_from_disk(de->rec_len, extra_size);
1564         }
1565 out:
1566         kfree(dir_buf);
1567         brelse(iloc.bh);
1568         return ret;
1569 }
1570
1571 struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
1572                                         struct ext4_dir_entry_2 **parent_de,
1573                                         int *retval)
1574 {
1575         struct ext4_iloc iloc;
1576
1577         *retval = ext4_get_inode_loc(inode, &iloc);
1578         if (*retval)
1579                 return NULL;
1580
1581         *parent_de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1582
1583         return iloc.bh;
1584 }
1585
1586 /*
1587  * Try to create the inline data for the new dir.
1588  * If it succeeds, return 0, otherwise return the error.
1589  * In case of ENOSPC, the caller should create the normal disk layout dir.
1590  */
1591 int ext4_try_create_inline_dir(handle_t *handle, struct inode *parent,
1592                                struct inode *inode)
1593 {
1594         int ret, inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1595         struct ext4_iloc iloc;
1596         struct ext4_dir_entry_2 *de;
1597
1598         ret = ext4_get_inode_loc(inode, &iloc);
1599         if (ret)
1600                 return ret;
1601
1602         ret = ext4_prepare_inline_data(handle, inode, inline_size);
1603         if (ret)
1604                 goto out;
1605
1606         /*
1607          * For inline dir, we only save the inode information for the ".."
1608          * and create a fake dentry to cover the left space.
1609          */
1610         de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1611         de->inode = cpu_to_le32(parent->i_ino);
1612         de = (struct ext4_dir_entry_2 *)((void *)de + EXT4_INLINE_DOTDOT_SIZE);
1613         de->inode = 0;
1614         de->rec_len = ext4_rec_len_to_disk(
1615                                 inline_size - EXT4_INLINE_DOTDOT_SIZE,
1616                                 inline_size);
1617         set_nlink(inode, 2);
1618         inode->i_size = EXT4_I(inode)->i_disksize = inline_size;
1619 out:
1620         brelse(iloc.bh);
1621         return ret;
1622 }
1623
1624 struct buffer_head *ext4_find_inline_entry(struct inode *dir,
1625                                         struct ext4_filename *fname,
1626                                         struct ext4_dir_entry_2 **res_dir,
1627                                         int *has_inline_data)
1628 {
1629         int ret;
1630         struct ext4_iloc iloc;
1631         void *inline_start;
1632         int inline_size;
1633
1634         if (ext4_get_inode_loc(dir, &iloc))
1635                 return NULL;
1636
1637         down_read(&EXT4_I(dir)->xattr_sem);
1638         if (!ext4_has_inline_data(dir)) {
1639                 *has_inline_data = 0;
1640                 goto out;
1641         }
1642
1643         inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1644                                                 EXT4_INLINE_DOTDOT_SIZE;
1645         inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1646         ret = ext4_search_dir(iloc.bh, inline_start, inline_size,
1647                               dir, fname, 0, res_dir);
1648         if (ret == 1)
1649                 goto out_find;
1650         if (ret < 0)
1651                 goto out;
1652
1653         if (ext4_get_inline_size(dir) == EXT4_MIN_INLINE_DATA_SIZE)
1654                 goto out;
1655
1656         inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1657         inline_size = ext4_get_inline_size(dir) - EXT4_MIN_INLINE_DATA_SIZE;
1658
1659         ret = ext4_search_dir(iloc.bh, inline_start, inline_size,
1660                               dir, fname, 0, res_dir);
1661         if (ret == 1)
1662                 goto out_find;
1663
1664 out:
1665         brelse(iloc.bh);
1666         iloc.bh = NULL;
1667 out_find:
1668         up_read(&EXT4_I(dir)->xattr_sem);
1669         return iloc.bh;
1670 }
1671
1672 int ext4_delete_inline_entry(handle_t *handle,
1673                              struct inode *dir,
1674                              struct ext4_dir_entry_2 *de_del,
1675                              struct buffer_head *bh,
1676                              int *has_inline_data)
1677 {
1678         int err, inline_size, no_expand;
1679         struct ext4_iloc iloc;
1680         void *inline_start;
1681
1682         err = ext4_get_inode_loc(dir, &iloc);
1683         if (err)
1684                 return err;
1685
1686         ext4_write_lock_xattr(dir, &no_expand);
1687         if (!ext4_has_inline_data(dir)) {
1688                 *has_inline_data = 0;
1689                 goto out;
1690         }
1691
1692         if ((void *)de_del - ((void *)ext4_raw_inode(&iloc)->i_block) <
1693                 EXT4_MIN_INLINE_DATA_SIZE) {
1694                 inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1695                                         EXT4_INLINE_DOTDOT_SIZE;
1696                 inline_size = EXT4_MIN_INLINE_DATA_SIZE -
1697                                 EXT4_INLINE_DOTDOT_SIZE;
1698         } else {
1699                 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1700                 inline_size = ext4_get_inline_size(dir) -
1701                                 EXT4_MIN_INLINE_DATA_SIZE;
1702         }
1703
1704         BUFFER_TRACE(bh, "get_write_access");
1705         err = ext4_journal_get_write_access(handle, bh);
1706         if (err)
1707                 goto out;
1708
1709         err = ext4_generic_delete_entry(dir, de_del, bh,
1710                                         inline_start, inline_size, 0);
1711         if (err)
1712                 goto out;
1713
1714         ext4_show_inline_dir(dir, iloc.bh, inline_start, inline_size);
1715 out:
1716         ext4_write_unlock_xattr(dir, &no_expand);
1717         if (likely(err == 0))
1718                 err = ext4_mark_inode_dirty(handle, dir);
1719         brelse(iloc.bh);
1720         if (err != -ENOENT)
1721                 ext4_std_error(dir->i_sb, err);
1722         return err;
1723 }
1724
1725 /*
1726  * Get the inline dentry at offset.
1727  */
1728 static inline struct ext4_dir_entry_2 *
1729 ext4_get_inline_entry(struct inode *inode,
1730                       struct ext4_iloc *iloc,
1731                       unsigned int offset,
1732                       void **inline_start,
1733                       int *inline_size)
1734 {
1735         void *inline_pos;
1736
1737         BUG_ON(offset > ext4_get_inline_size(inode));
1738
1739         if (offset < EXT4_MIN_INLINE_DATA_SIZE) {
1740                 inline_pos = (void *)ext4_raw_inode(iloc)->i_block;
1741                 *inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1742         } else {
1743                 inline_pos = ext4_get_inline_xattr_pos(inode, iloc);
1744                 offset -= EXT4_MIN_INLINE_DATA_SIZE;
1745                 *inline_size = ext4_get_inline_size(inode) -
1746                                 EXT4_MIN_INLINE_DATA_SIZE;
1747         }
1748
1749         if (inline_start)
1750                 *inline_start = inline_pos;
1751         return (struct ext4_dir_entry_2 *)(inline_pos + offset);
1752 }
1753
1754 bool empty_inline_dir(struct inode *dir, int *has_inline_data)
1755 {
1756         int err, inline_size;
1757         struct ext4_iloc iloc;
1758         size_t inline_len;
1759         void *inline_pos;
1760         unsigned int offset;
1761         struct ext4_dir_entry_2 *de;
1762         bool ret = true;
1763
1764         err = ext4_get_inode_loc(dir, &iloc);
1765         if (err) {
1766                 EXT4_ERROR_INODE_ERR(dir, -err,
1767                                      "error %d getting inode %lu block",
1768                                      err, dir->i_ino);
1769                 return true;
1770         }
1771
1772         down_read(&EXT4_I(dir)->xattr_sem);
1773         if (!ext4_has_inline_data(dir)) {
1774                 *has_inline_data = 0;
1775                 goto out;
1776         }
1777
1778         de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1779         if (!le32_to_cpu(de->inode)) {
1780                 ext4_warning(dir->i_sb,
1781                              "bad inline directory (dir #%lu) - no `..'",
1782                              dir->i_ino);
1783                 ret = true;
1784                 goto out;
1785         }
1786
1787         inline_len = ext4_get_inline_size(dir);
1788         offset = EXT4_INLINE_DOTDOT_SIZE;
1789         while (offset < inline_len) {
1790                 de = ext4_get_inline_entry(dir, &iloc, offset,
1791                                            &inline_pos, &inline_size);
1792                 if (ext4_check_dir_entry(dir, NULL, de,
1793                                          iloc.bh, inline_pos,
1794                                          inline_size, offset)) {
1795                         ext4_warning(dir->i_sb,
1796                                      "bad inline directory (dir #%lu) - "
1797                                      "inode %u, rec_len %u, name_len %d"
1798                                      "inline size %d",
1799                                      dir->i_ino, le32_to_cpu(de->inode),
1800                                      le16_to_cpu(de->rec_len), de->name_len,
1801                                      inline_size);
1802                         ret = true;
1803                         goto out;
1804                 }
1805                 if (le32_to_cpu(de->inode)) {
1806                         ret = false;
1807                         goto out;
1808                 }
1809                 offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
1810         }
1811
1812 out:
1813         up_read(&EXT4_I(dir)->xattr_sem);
1814         brelse(iloc.bh);
1815         return ret;
1816 }
1817
1818 int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
1819 {
1820         int ret, no_expand;
1821
1822         ext4_write_lock_xattr(inode, &no_expand);
1823         ret = ext4_destroy_inline_data_nolock(handle, inode);
1824         ext4_write_unlock_xattr(inode, &no_expand);
1825
1826         return ret;
1827 }
1828
1829 int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap)
1830 {
1831         __u64 addr;
1832         int error = -EAGAIN;
1833         struct ext4_iloc iloc;
1834
1835         down_read(&EXT4_I(inode)->xattr_sem);
1836         if (!ext4_has_inline_data(inode))
1837                 goto out;
1838
1839         error = ext4_get_inode_loc(inode, &iloc);
1840         if (error)
1841                 goto out;
1842
1843         addr = (__u64)iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
1844         addr += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
1845         addr += offsetof(struct ext4_inode, i_block);
1846
1847         brelse(iloc.bh);
1848
1849         iomap->addr = addr;
1850         iomap->offset = 0;
1851         iomap->length = min_t(loff_t, ext4_get_inline_size(inode),
1852                               i_size_read(inode));
1853         iomap->type = IOMAP_INLINE;
1854         iomap->flags = 0;
1855
1856 out:
1857         up_read(&EXT4_I(inode)->xattr_sem);
1858         return error;
1859 }
1860
1861 int ext4_inline_data_truncate(struct inode *inode, int *has_inline)
1862 {
1863         handle_t *handle;
1864         int inline_size, value_len, needed_blocks, no_expand, err = 0;
1865         size_t i_size;
1866         void *value = NULL;
1867         struct ext4_xattr_ibody_find is = {
1868                 .s = { .not_found = -ENODATA, },
1869         };
1870         struct ext4_xattr_info i = {
1871                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
1872                 .name = EXT4_XATTR_SYSTEM_DATA,
1873         };
1874
1875
1876         needed_blocks = ext4_writepage_trans_blocks(inode);
1877         handle = ext4_journal_start(inode, EXT4_HT_INODE, needed_blocks);
1878         if (IS_ERR(handle))
1879                 return PTR_ERR(handle);
1880
1881         ext4_write_lock_xattr(inode, &no_expand);
1882         if (!ext4_has_inline_data(inode)) {
1883                 ext4_write_unlock_xattr(inode, &no_expand);
1884                 *has_inline = 0;
1885                 ext4_journal_stop(handle);
1886                 return 0;
1887         }
1888
1889         if ((err = ext4_orphan_add(handle, inode)) != 0)
1890                 goto out;
1891
1892         if ((err = ext4_get_inode_loc(inode, &is.iloc)) != 0)
1893                 goto out;
1894
1895         down_write(&EXT4_I(inode)->i_data_sem);
1896         i_size = inode->i_size;
1897         inline_size = ext4_get_inline_size(inode);
1898         EXT4_I(inode)->i_disksize = i_size;
1899
1900         if (i_size < inline_size) {
1901                 /* Clear the content in the xattr space. */
1902                 if (inline_size > EXT4_MIN_INLINE_DATA_SIZE) {
1903                         if ((err = ext4_xattr_ibody_find(inode, &i, &is)) != 0)
1904                                 goto out_error;
1905
1906                         BUG_ON(is.s.not_found);
1907
1908                         value_len = le32_to_cpu(is.s.here->e_value_size);
1909                         value = kmalloc(value_len, GFP_NOFS);
1910                         if (!value) {
1911                                 err = -ENOMEM;
1912                                 goto out_error;
1913                         }
1914
1915                         err = ext4_xattr_ibody_get(inode, i.name_index,
1916                                                    i.name, value, value_len);
1917                         if (err <= 0)
1918                                 goto out_error;
1919
1920                         i.value = value;
1921                         i.value_len = i_size > EXT4_MIN_INLINE_DATA_SIZE ?
1922                                         i_size - EXT4_MIN_INLINE_DATA_SIZE : 0;
1923                         err = ext4_xattr_ibody_inline_set(handle, inode,
1924                                                           &i, &is);
1925                         if (err)
1926                                 goto out_error;
1927                 }
1928
1929                 /* Clear the content within i_blocks. */
1930                 if (i_size < EXT4_MIN_INLINE_DATA_SIZE) {
1931                         void *p = (void *) ext4_raw_inode(&is.iloc)->i_block;
1932                         memset(p + i_size, 0,
1933                                EXT4_MIN_INLINE_DATA_SIZE - i_size);
1934                 }
1935
1936                 EXT4_I(inode)->i_inline_size = i_size <
1937                                         EXT4_MIN_INLINE_DATA_SIZE ?
1938                                         EXT4_MIN_INLINE_DATA_SIZE : i_size;
1939         }
1940
1941 out_error:
1942         up_write(&EXT4_I(inode)->i_data_sem);
1943 out:
1944         brelse(is.iloc.bh);
1945         ext4_write_unlock_xattr(inode, &no_expand);
1946         kfree(value);
1947         if (inode->i_nlink)
1948                 ext4_orphan_del(handle, inode);
1949
1950         if (err == 0) {
1951                 inode->i_mtime = inode->i_ctime = current_time(inode);
1952                 err = ext4_mark_inode_dirty(handle, inode);
1953                 if (IS_SYNC(inode))
1954                         ext4_handle_sync(handle);
1955         }
1956         ext4_journal_stop(handle);
1957         return err;
1958 }
1959
1960 int ext4_convert_inline_data(struct inode *inode)
1961 {
1962         int error, needed_blocks, no_expand;
1963         handle_t *handle;
1964         struct ext4_iloc iloc;
1965
1966         if (!ext4_has_inline_data(inode)) {
1967                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1968                 return 0;
1969         }
1970
1971         needed_blocks = ext4_writepage_trans_blocks(inode);
1972
1973         iloc.bh = NULL;
1974         error = ext4_get_inode_loc(inode, &iloc);
1975         if (error)
1976                 return error;
1977
1978         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
1979         if (IS_ERR(handle)) {
1980                 error = PTR_ERR(handle);
1981                 goto out_free;
1982         }
1983
1984         ext4_write_lock_xattr(inode, &no_expand);
1985         if (ext4_has_inline_data(inode))
1986                 error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
1987         ext4_write_unlock_xattr(inode, &no_expand);
1988         ext4_journal_stop(handle);
1989 out_free:
1990         brelse(iloc.bh);
1991         return error;
1992 }