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Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[deliverable/linux.git] / fs / ext4 / inline.c
1 /*
2 * Copyright (c) 2012 Taobao.
3 * Written by Tao Ma <boyu.mt@taobao.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of version 2.1 of the GNU Lesser General Public License
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14 #include "ext4_jbd2.h"
15 #include "ext4.h"
16 #include "xattr.h"
17 #include "truncate.h"
18 #include <linux/fiemap.h>
19
20 #define EXT4_XATTR_SYSTEM_DATA "data"
21 #define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__le32) * EXT4_N_BLOCKS))
22 #define EXT4_INLINE_DOTDOT_OFFSET 2
23 #define EXT4_INLINE_DOTDOT_SIZE 4
24
25 static int ext4_get_inline_size(struct inode *inode)
26 {
27 if (EXT4_I(inode)->i_inline_off)
28 return EXT4_I(inode)->i_inline_size;
29
30 return 0;
31 }
32
33 static int get_max_inline_xattr_value_size(struct inode *inode,
34 struct ext4_iloc *iloc)
35 {
36 struct ext4_xattr_ibody_header *header;
37 struct ext4_xattr_entry *entry;
38 struct ext4_inode *raw_inode;
39 int free, min_offs;
40
41 min_offs = EXT4_SB(inode->i_sb)->s_inode_size -
42 EXT4_GOOD_OLD_INODE_SIZE -
43 EXT4_I(inode)->i_extra_isize -
44 sizeof(struct ext4_xattr_ibody_header);
45
46 /*
47 * We need to subtract another sizeof(__u32) since an in-inode xattr
48 * needs an empty 4 bytes to indicate the gap between the xattr entry
49 * and the name/value pair.
50 */
51 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
52 return EXT4_XATTR_SIZE(min_offs -
53 EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA)) -
54 EXT4_XATTR_ROUND - sizeof(__u32));
55
56 raw_inode = ext4_raw_inode(iloc);
57 header = IHDR(inode, raw_inode);
58 entry = IFIRST(header);
59
60 /* Compute min_offs. */
61 for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
62 if (!entry->e_value_block && entry->e_value_size) {
63 size_t offs = le16_to_cpu(entry->e_value_offs);
64 if (offs < min_offs)
65 min_offs = offs;
66 }
67 }
68 free = min_offs -
69 ((void *)entry - (void *)IFIRST(header)) - sizeof(__u32);
70
71 if (EXT4_I(inode)->i_inline_off) {
72 entry = (struct ext4_xattr_entry *)
73 ((void *)raw_inode + EXT4_I(inode)->i_inline_off);
74
75 free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
76 goto out;
77 }
78
79 free -= EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA));
80
81 if (free > EXT4_XATTR_ROUND)
82 free = EXT4_XATTR_SIZE(free - EXT4_XATTR_ROUND);
83 else
84 free = 0;
85
86 out:
87 return free;
88 }
89
90 /*
91 * Get the maximum size we now can store in an inode.
92 * If we can't find the space for a xattr entry, don't use the space
93 * of the extents since we have no space to indicate the inline data.
94 */
95 int ext4_get_max_inline_size(struct inode *inode)
96 {
97 int error, max_inline_size;
98 struct ext4_iloc iloc;
99
100 if (EXT4_I(inode)->i_extra_isize == 0)
101 return 0;
102
103 error = ext4_get_inode_loc(inode, &iloc);
104 if (error) {
105 ext4_error_inode(inode, __func__, __LINE__, 0,
106 "can't get inode location %lu",
107 inode->i_ino);
108 return 0;
109 }
110
111 down_read(&EXT4_I(inode)->xattr_sem);
112 max_inline_size = get_max_inline_xattr_value_size(inode, &iloc);
113 up_read(&EXT4_I(inode)->xattr_sem);
114
115 brelse(iloc.bh);
116
117 if (!max_inline_size)
118 return 0;
119
120 return max_inline_size + EXT4_MIN_INLINE_DATA_SIZE;
121 }
122
123 /*
124 * this function does not take xattr_sem, which is OK because it is
125 * currently only used in a code path coming form ext4_iget, before
126 * the new inode has been unlocked
127 */
128 int ext4_find_inline_data_nolock(struct inode *inode)
129 {
130 struct ext4_xattr_ibody_find is = {
131 .s = { .not_found = -ENODATA, },
132 };
133 struct ext4_xattr_info i = {
134 .name_index = EXT4_XATTR_INDEX_SYSTEM,
135 .name = EXT4_XATTR_SYSTEM_DATA,
136 };
137 int error;
138
139 if (EXT4_I(inode)->i_extra_isize == 0)
140 return 0;
141
142 error = ext4_get_inode_loc(inode, &is.iloc);
143 if (error)
144 return error;
145
146 error = ext4_xattr_ibody_find(inode, &i, &is);
147 if (error)
148 goto out;
149
150 if (!is.s.not_found) {
151 EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
152 (void *)ext4_raw_inode(&is.iloc));
153 EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
154 le32_to_cpu(is.s.here->e_value_size);
155 ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
156 }
157 out:
158 brelse(is.iloc.bh);
159 return error;
160 }
161
162 static int ext4_read_inline_data(struct inode *inode, void *buffer,
163 unsigned int len,
164 struct ext4_iloc *iloc)
165 {
166 struct ext4_xattr_entry *entry;
167 struct ext4_xattr_ibody_header *header;
168 int cp_len = 0;
169 struct ext4_inode *raw_inode;
170
171 if (!len)
172 return 0;
173
174 BUG_ON(len > EXT4_I(inode)->i_inline_size);
175
176 cp_len = len < EXT4_MIN_INLINE_DATA_SIZE ?
177 len : EXT4_MIN_INLINE_DATA_SIZE;
178
179 raw_inode = ext4_raw_inode(iloc);
180 memcpy(buffer, (void *)(raw_inode->i_block), cp_len);
181
182 len -= cp_len;
183 buffer += cp_len;
184
185 if (!len)
186 goto out;
187
188 header = IHDR(inode, raw_inode);
189 entry = (struct ext4_xattr_entry *)((void *)raw_inode +
190 EXT4_I(inode)->i_inline_off);
191 len = min_t(unsigned int, len,
192 (unsigned int)le32_to_cpu(entry->e_value_size));
193
194 memcpy(buffer,
195 (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs), len);
196 cp_len += len;
197
198 out:
199 return cp_len;
200 }
201
202 /*
203 * write the buffer to the inline inode.
204 * If 'create' is set, we don't need to do the extra copy in the xattr
205 * value since it is already handled by ext4_xattr_ibody_inline_set.
206 * That saves us one memcpy.
207 */
208 static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
209 void *buffer, loff_t pos, unsigned int len)
210 {
211 struct ext4_xattr_entry *entry;
212 struct ext4_xattr_ibody_header *header;
213 struct ext4_inode *raw_inode;
214 int cp_len = 0;
215
216 BUG_ON(!EXT4_I(inode)->i_inline_off);
217 BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
218
219 raw_inode = ext4_raw_inode(iloc);
220 buffer += pos;
221
222 if (pos < EXT4_MIN_INLINE_DATA_SIZE) {
223 cp_len = pos + len > EXT4_MIN_INLINE_DATA_SIZE ?
224 EXT4_MIN_INLINE_DATA_SIZE - pos : len;
225 memcpy((void *)raw_inode->i_block + pos, buffer, cp_len);
226
227 len -= cp_len;
228 buffer += cp_len;
229 pos += cp_len;
230 }
231
232 if (!len)
233 return;
234
235 pos -= EXT4_MIN_INLINE_DATA_SIZE;
236 header = IHDR(inode, raw_inode);
237 entry = (struct ext4_xattr_entry *)((void *)raw_inode +
238 EXT4_I(inode)->i_inline_off);
239
240 memcpy((void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs) + pos,
241 buffer, len);
242 }
243
244 static int ext4_create_inline_data(handle_t *handle,
245 struct inode *inode, unsigned len)
246 {
247 int error;
248 void *value = NULL;
249 struct ext4_xattr_ibody_find is = {
250 .s = { .not_found = -ENODATA, },
251 };
252 struct ext4_xattr_info i = {
253 .name_index = EXT4_XATTR_INDEX_SYSTEM,
254 .name = EXT4_XATTR_SYSTEM_DATA,
255 };
256
257 error = ext4_get_inode_loc(inode, &is.iloc);
258 if (error)
259 return error;
260
261 BUFFER_TRACE(is.iloc.bh, "get_write_access");
262 error = ext4_journal_get_write_access(handle, is.iloc.bh);
263 if (error)
264 goto out;
265
266 if (len > EXT4_MIN_INLINE_DATA_SIZE) {
267 value = EXT4_ZERO_XATTR_VALUE;
268 len -= EXT4_MIN_INLINE_DATA_SIZE;
269 } else {
270 value = "";
271 len = 0;
272 }
273
274 /* Insert the the xttr entry. */
275 i.value = value;
276 i.value_len = len;
277
278 error = ext4_xattr_ibody_find(inode, &i, &is);
279 if (error)
280 goto out;
281
282 BUG_ON(!is.s.not_found);
283
284 error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
285 if (error) {
286 if (error == -ENOSPC)
287 ext4_clear_inode_state(inode,
288 EXT4_STATE_MAY_INLINE_DATA);
289 goto out;
290 }
291
292 memset((void *)ext4_raw_inode(&is.iloc)->i_block,
293 0, EXT4_MIN_INLINE_DATA_SIZE);
294
295 EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
296 (void *)ext4_raw_inode(&is.iloc));
297 EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
298 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
299 ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
300 get_bh(is.iloc.bh);
301 error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
302
303 out:
304 brelse(is.iloc.bh);
305 return error;
306 }
307
308 static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
309 unsigned int len)
310 {
311 int error;
312 void *value = NULL;
313 struct ext4_xattr_ibody_find is = {
314 .s = { .not_found = -ENODATA, },
315 };
316 struct ext4_xattr_info i = {
317 .name_index = EXT4_XATTR_INDEX_SYSTEM,
318 .name = EXT4_XATTR_SYSTEM_DATA,
319 };
320
321 /* If the old space is ok, write the data directly. */
322 if (len <= EXT4_I(inode)->i_inline_size)
323 return 0;
324
325 error = ext4_get_inode_loc(inode, &is.iloc);
326 if (error)
327 return error;
328
329 error = ext4_xattr_ibody_find(inode, &i, &is);
330 if (error)
331 goto out;
332
333 BUG_ON(is.s.not_found);
334
335 len -= EXT4_MIN_INLINE_DATA_SIZE;
336 value = kzalloc(len, GFP_NOFS);
337 if (!value)
338 goto out;
339
340 error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
341 value, len);
342 if (error == -ENODATA)
343 goto out;
344
345 BUFFER_TRACE(is.iloc.bh, "get_write_access");
346 error = ext4_journal_get_write_access(handle, is.iloc.bh);
347 if (error)
348 goto out;
349
350 /* Update the xttr entry. */
351 i.value = value;
352 i.value_len = len;
353
354 error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
355 if (error)
356 goto out;
357
358 EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
359 (void *)ext4_raw_inode(&is.iloc));
360 EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
361 le32_to_cpu(is.s.here->e_value_size);
362 ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
363 get_bh(is.iloc.bh);
364 error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
365
366 out:
367 kfree(value);
368 brelse(is.iloc.bh);
369 return error;
370 }
371
372 static int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
373 unsigned int len)
374 {
375 int ret, size;
376 struct ext4_inode_info *ei = EXT4_I(inode);
377
378 if (!ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
379 return -ENOSPC;
380
381 size = ext4_get_max_inline_size(inode);
382 if (size < len)
383 return -ENOSPC;
384
385 down_write(&EXT4_I(inode)->xattr_sem);
386
387 if (ei->i_inline_off)
388 ret = ext4_update_inline_data(handle, inode, len);
389 else
390 ret = ext4_create_inline_data(handle, inode, len);
391
392 up_write(&EXT4_I(inode)->xattr_sem);
393
394 return ret;
395 }
396
397 static int ext4_destroy_inline_data_nolock(handle_t *handle,
398 struct inode *inode)
399 {
400 struct ext4_inode_info *ei = EXT4_I(inode);
401 struct ext4_xattr_ibody_find is = {
402 .s = { .not_found = 0, },
403 };
404 struct ext4_xattr_info i = {
405 .name_index = EXT4_XATTR_INDEX_SYSTEM,
406 .name = EXT4_XATTR_SYSTEM_DATA,
407 .value = NULL,
408 .value_len = 0,
409 };
410 int error;
411
412 if (!ei->i_inline_off)
413 return 0;
414
415 error = ext4_get_inode_loc(inode, &is.iloc);
416 if (error)
417 return error;
418
419 error = ext4_xattr_ibody_find(inode, &i, &is);
420 if (error)
421 goto out;
422
423 BUFFER_TRACE(is.iloc.bh, "get_write_access");
424 error = ext4_journal_get_write_access(handle, is.iloc.bh);
425 if (error)
426 goto out;
427
428 error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
429 if (error)
430 goto out;
431
432 memset((void *)ext4_raw_inode(&is.iloc)->i_block,
433 0, EXT4_MIN_INLINE_DATA_SIZE);
434
435 if (EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
436 EXT4_FEATURE_INCOMPAT_EXTENTS)) {
437 if (S_ISDIR(inode->i_mode) ||
438 S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)) {
439 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
440 ext4_ext_tree_init(handle, inode);
441 }
442 }
443 ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
444
445 get_bh(is.iloc.bh);
446 error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
447
448 EXT4_I(inode)->i_inline_off = 0;
449 EXT4_I(inode)->i_inline_size = 0;
450 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
451 out:
452 brelse(is.iloc.bh);
453 if (error == -ENODATA)
454 error = 0;
455 return error;
456 }
457
458 static int ext4_read_inline_page(struct inode *inode, struct page *page)
459 {
460 void *kaddr;
461 int ret = 0;
462 size_t len;
463 struct ext4_iloc iloc;
464
465 BUG_ON(!PageLocked(page));
466 BUG_ON(!ext4_has_inline_data(inode));
467 BUG_ON(page->index);
468
469 if (!EXT4_I(inode)->i_inline_off) {
470 ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
471 inode->i_ino);
472 goto out;
473 }
474
475 ret = ext4_get_inode_loc(inode, &iloc);
476 if (ret)
477 goto out;
478
479 len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
480 kaddr = kmap_atomic(page);
481 ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
482 flush_dcache_page(page);
483 kunmap_atomic(kaddr);
484 zero_user_segment(page, len, PAGE_CACHE_SIZE);
485 SetPageUptodate(page);
486 brelse(iloc.bh);
487
488 out:
489 return ret;
490 }
491
492 int ext4_readpage_inline(struct inode *inode, struct page *page)
493 {
494 int ret = 0;
495
496 down_read(&EXT4_I(inode)->xattr_sem);
497 if (!ext4_has_inline_data(inode)) {
498 up_read(&EXT4_I(inode)->xattr_sem);
499 return -EAGAIN;
500 }
501
502 /*
503 * Current inline data can only exist in the 1st page,
504 * So for all the other pages, just set them uptodate.
505 */
506 if (!page->index)
507 ret = ext4_read_inline_page(inode, page);
508 else if (!PageUptodate(page)) {
509 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
510 SetPageUptodate(page);
511 }
512
513 up_read(&EXT4_I(inode)->xattr_sem);
514
515 unlock_page(page);
516 return ret >= 0 ? 0 : ret;
517 }
518
519 static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
520 struct inode *inode,
521 unsigned flags)
522 {
523 int ret, needed_blocks;
524 handle_t *handle = NULL;
525 int retries = 0, sem_held = 0;
526 struct page *page = NULL;
527 unsigned from, to;
528 struct ext4_iloc iloc;
529
530 if (!ext4_has_inline_data(inode)) {
531 /*
532 * clear the flag so that no new write
533 * will trap here again.
534 */
535 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
536 return 0;
537 }
538
539 needed_blocks = ext4_writepage_trans_blocks(inode);
540
541 ret = ext4_get_inode_loc(inode, &iloc);
542 if (ret)
543 return ret;
544
545 retry:
546 handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
547 if (IS_ERR(handle)) {
548 ret = PTR_ERR(handle);
549 handle = NULL;
550 goto out;
551 }
552
553 /* We cannot recurse into the filesystem as the transaction is already
554 * started */
555 flags |= AOP_FLAG_NOFS;
556
557 page = grab_cache_page_write_begin(mapping, 0, flags);
558 if (!page) {
559 ret = -ENOMEM;
560 goto out;
561 }
562
563 down_write(&EXT4_I(inode)->xattr_sem);
564 sem_held = 1;
565 /* If some one has already done this for us, just exit. */
566 if (!ext4_has_inline_data(inode)) {
567 ret = 0;
568 goto out;
569 }
570
571 from = 0;
572 to = ext4_get_inline_size(inode);
573 if (!PageUptodate(page)) {
574 ret = ext4_read_inline_page(inode, page);
575 if (ret < 0)
576 goto out;
577 }
578
579 ret = ext4_destroy_inline_data_nolock(handle, inode);
580 if (ret)
581 goto out;
582
583 if (ext4_should_dioread_nolock(inode))
584 ret = __block_write_begin(page, from, to, ext4_get_block_write);
585 else
586 ret = __block_write_begin(page, from, to, ext4_get_block);
587
588 if (!ret && ext4_should_journal_data(inode)) {
589 ret = ext4_walk_page_buffers(handle, page_buffers(page),
590 from, to, NULL,
591 do_journal_get_write_access);
592 }
593
594 if (ret) {
595 unlock_page(page);
596 page_cache_release(page);
597 page = NULL;
598 ext4_orphan_add(handle, inode);
599 up_write(&EXT4_I(inode)->xattr_sem);
600 sem_held = 0;
601 ext4_journal_stop(handle);
602 handle = NULL;
603 ext4_truncate_failed_write(inode);
604 /*
605 * If truncate failed early the inode might
606 * still be on the orphan list; we need to
607 * make sure the inode is removed from the
608 * orphan list in that case.
609 */
610 if (inode->i_nlink)
611 ext4_orphan_del(NULL, inode);
612 }
613
614 if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
615 goto retry;
616
617 if (page)
618 block_commit_write(page, from, to);
619 out:
620 if (page) {
621 unlock_page(page);
622 page_cache_release(page);
623 }
624 if (sem_held)
625 up_write(&EXT4_I(inode)->xattr_sem);
626 if (handle)
627 ext4_journal_stop(handle);
628 brelse(iloc.bh);
629 return ret;
630 }
631
632 /*
633 * Try to write data in the inode.
634 * If the inode has inline data, check whether the new write can be
635 * in the inode also. If not, create the page the handle, move the data
636 * to the page make it update and let the later codes create extent for it.
637 */
638 int ext4_try_to_write_inline_data(struct address_space *mapping,
639 struct inode *inode,
640 loff_t pos, unsigned len,
641 unsigned flags,
642 struct page **pagep)
643 {
644 int ret;
645 handle_t *handle;
646 struct page *page;
647 struct ext4_iloc iloc;
648
649 if (pos + len > ext4_get_max_inline_size(inode))
650 goto convert;
651
652 ret = ext4_get_inode_loc(inode, &iloc);
653 if (ret)
654 return ret;
655
656 /*
657 * The possible write could happen in the inode,
658 * so try to reserve the space in inode first.
659 */
660 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
661 if (IS_ERR(handle)) {
662 ret = PTR_ERR(handle);
663 handle = NULL;
664 goto out;
665 }
666
667 ret = ext4_prepare_inline_data(handle, inode, pos + len);
668 if (ret && ret != -ENOSPC)
669 goto out;
670
671 /* We don't have space in inline inode, so convert it to extent. */
672 if (ret == -ENOSPC) {
673 ext4_journal_stop(handle);
674 brelse(iloc.bh);
675 goto convert;
676 }
677
678 flags |= AOP_FLAG_NOFS;
679
680 page = grab_cache_page_write_begin(mapping, 0, flags);
681 if (!page) {
682 ret = -ENOMEM;
683 goto out;
684 }
685
686 *pagep = page;
687 down_read(&EXT4_I(inode)->xattr_sem);
688 if (!ext4_has_inline_data(inode)) {
689 ret = 0;
690 unlock_page(page);
691 page_cache_release(page);
692 goto out_up_read;
693 }
694
695 if (!PageUptodate(page)) {
696 ret = ext4_read_inline_page(inode, page);
697 if (ret < 0)
698 goto out_up_read;
699 }
700
701 ret = 1;
702 handle = NULL;
703 out_up_read:
704 up_read(&EXT4_I(inode)->xattr_sem);
705 out:
706 if (handle)
707 ext4_journal_stop(handle);
708 brelse(iloc.bh);
709 return ret;
710 convert:
711 return ext4_convert_inline_data_to_extent(mapping,
712 inode, flags);
713 }
714
715 int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
716 unsigned copied, struct page *page)
717 {
718 int ret;
719 void *kaddr;
720 struct ext4_iloc iloc;
721
722 if (unlikely(copied < len)) {
723 if (!PageUptodate(page)) {
724 copied = 0;
725 goto out;
726 }
727 }
728
729 ret = ext4_get_inode_loc(inode, &iloc);
730 if (ret) {
731 ext4_std_error(inode->i_sb, ret);
732 copied = 0;
733 goto out;
734 }
735
736 down_write(&EXT4_I(inode)->xattr_sem);
737 BUG_ON(!ext4_has_inline_data(inode));
738
739 kaddr = kmap_atomic(page);
740 ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
741 kunmap_atomic(kaddr);
742 SetPageUptodate(page);
743 /* clear page dirty so that writepages wouldn't work for us. */
744 ClearPageDirty(page);
745
746 up_write(&EXT4_I(inode)->xattr_sem);
747 brelse(iloc.bh);
748 out:
749 return copied;
750 }
751
752 struct buffer_head *
753 ext4_journalled_write_inline_data(struct inode *inode,
754 unsigned len,
755 struct page *page)
756 {
757 int ret;
758 void *kaddr;
759 struct ext4_iloc iloc;
760
761 ret = ext4_get_inode_loc(inode, &iloc);
762 if (ret) {
763 ext4_std_error(inode->i_sb, ret);
764 return NULL;
765 }
766
767 down_write(&EXT4_I(inode)->xattr_sem);
768 kaddr = kmap_atomic(page);
769 ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
770 kunmap_atomic(kaddr);
771 up_write(&EXT4_I(inode)->xattr_sem);
772
773 return iloc.bh;
774 }
775
776 /*
777 * Try to make the page cache and handle ready for the inline data case.
778 * We can call this function in 2 cases:
779 * 1. The inode is created and the first write exceeds inline size. We can
780 * clear the inode state safely.
781 * 2. The inode has inline data, then we need to read the data, make it
782 * update and dirty so that ext4_da_writepages can handle it. We don't
783 * need to start the journal since the file's metatdata isn't changed now.
784 */
785 static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
786 struct inode *inode,
787 unsigned flags,
788 void **fsdata)
789 {
790 int ret = 0, inline_size;
791 struct page *page;
792
793 page = grab_cache_page_write_begin(mapping, 0, flags);
794 if (!page)
795 return -ENOMEM;
796
797 down_read(&EXT4_I(inode)->xattr_sem);
798 if (!ext4_has_inline_data(inode)) {
799 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
800 goto out;
801 }
802
803 inline_size = ext4_get_inline_size(inode);
804
805 if (!PageUptodate(page)) {
806 ret = ext4_read_inline_page(inode, page);
807 if (ret < 0)
808 goto out;
809 }
810
811 ret = __block_write_begin(page, 0, inline_size,
812 ext4_da_get_block_prep);
813 if (ret) {
814 ext4_truncate_failed_write(inode);
815 goto out;
816 }
817
818 SetPageDirty(page);
819 SetPageUptodate(page);
820 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
821 *fsdata = (void *)CONVERT_INLINE_DATA;
822
823 out:
824 up_read(&EXT4_I(inode)->xattr_sem);
825 if (page) {
826 unlock_page(page);
827 page_cache_release(page);
828 }
829 return ret;
830 }
831
832 /*
833 * Prepare the write for the inline data.
834 * If the the data can be written into the inode, we just read
835 * the page and make it uptodate, and start the journal.
836 * Otherwise read the page, makes it dirty so that it can be
837 * handle in writepages(the i_disksize update is left to the
838 * normal ext4_da_write_end).
839 */
840 int ext4_da_write_inline_data_begin(struct address_space *mapping,
841 struct inode *inode,
842 loff_t pos, unsigned len,
843 unsigned flags,
844 struct page **pagep,
845 void **fsdata)
846 {
847 int ret, inline_size;
848 handle_t *handle;
849 struct page *page;
850 struct ext4_iloc iloc;
851 int retries;
852
853 ret = ext4_get_inode_loc(inode, &iloc);
854 if (ret)
855 return ret;
856
857 retry_journal:
858 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
859 if (IS_ERR(handle)) {
860 ret = PTR_ERR(handle);
861 goto out;
862 }
863
864 inline_size = ext4_get_max_inline_size(inode);
865
866 ret = -ENOSPC;
867 if (inline_size >= pos + len) {
868 ret = ext4_prepare_inline_data(handle, inode, pos + len);
869 if (ret && ret != -ENOSPC)
870 goto out_journal;
871 }
872
873 if (ret == -ENOSPC) {
874 ret = ext4_da_convert_inline_data_to_extent(mapping,
875 inode,
876 flags,
877 fsdata);
878 ext4_journal_stop(handle);
879 if (ret == -ENOSPC &&
880 ext4_should_retry_alloc(inode->i_sb, &retries))
881 goto retry_journal;
882 goto out;
883 }
884
885 /*
886 * We cannot recurse into the filesystem as the transaction
887 * is already started.
888 */
889 flags |= AOP_FLAG_NOFS;
890
891 page = grab_cache_page_write_begin(mapping, 0, flags);
892 if (!page) {
893 ret = -ENOMEM;
894 goto out_journal;
895 }
896
897 down_read(&EXT4_I(inode)->xattr_sem);
898 if (!ext4_has_inline_data(inode)) {
899 ret = 0;
900 goto out_release_page;
901 }
902
903 if (!PageUptodate(page)) {
904 ret = ext4_read_inline_page(inode, page);
905 if (ret < 0)
906 goto out_release_page;
907 }
908
909 up_read(&EXT4_I(inode)->xattr_sem);
910 *pagep = page;
911 brelse(iloc.bh);
912 return 1;
913 out_release_page:
914 up_read(&EXT4_I(inode)->xattr_sem);
915 unlock_page(page);
916 page_cache_release(page);
917 out_journal:
918 ext4_journal_stop(handle);
919 out:
920 brelse(iloc.bh);
921 return ret;
922 }
923
924 int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
925 unsigned len, unsigned copied,
926 struct page *page)
927 {
928 int i_size_changed = 0;
929
930 copied = ext4_write_inline_data_end(inode, pos, len, copied, page);
931
932 /*
933 * No need to use i_size_read() here, the i_size
934 * cannot change under us because we hold i_mutex.
935 *
936 * But it's important to update i_size while still holding page lock:
937 * page writeout could otherwise come in and zero beyond i_size.
938 */
939 if (pos+copied > inode->i_size) {
940 i_size_write(inode, pos+copied);
941 i_size_changed = 1;
942 }
943 unlock_page(page);
944 page_cache_release(page);
945
946 /*
947 * Don't mark the inode dirty under page lock. First, it unnecessarily
948 * makes the holding time of page lock longer. Second, it forces lock
949 * ordering of page lock and transaction start for journaling
950 * filesystems.
951 */
952 if (i_size_changed)
953 mark_inode_dirty(inode);
954
955 return copied;
956 }
957
958 #ifdef INLINE_DIR_DEBUG
959 void ext4_show_inline_dir(struct inode *dir, struct buffer_head *bh,
960 void *inline_start, int inline_size)
961 {
962 int offset;
963 unsigned short de_len;
964 struct ext4_dir_entry_2 *de = inline_start;
965 void *dlimit = inline_start + inline_size;
966
967 trace_printk("inode %lu\n", dir->i_ino);
968 offset = 0;
969 while ((void *)de < dlimit) {
970 de_len = ext4_rec_len_from_disk(de->rec_len, inline_size);
971 trace_printk("de: off %u rlen %u name %*.s nlen %u ino %u\n",
972 offset, de_len, de->name_len, de->name,
973 de->name_len, le32_to_cpu(de->inode));
974 if (ext4_check_dir_entry(dir, NULL, de, bh,
975 inline_start, inline_size, offset))
976 BUG();
977
978 offset += de_len;
979 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
980 }
981 }
982 #else
983 #define ext4_show_inline_dir(dir, bh, inline_start, inline_size)
984 #endif
985
986 /*
987 * Add a new entry into a inline dir.
988 * It will return -ENOSPC if no space is available, and -EIO
989 * and -EEXIST if directory entry already exists.
990 */
991 static int ext4_add_dirent_to_inline(handle_t *handle,
992 struct dentry *dentry,
993 struct inode *inode,
994 struct ext4_iloc *iloc,
995 void *inline_start, int inline_size)
996 {
997 struct inode *dir = dentry->d_parent->d_inode;
998 const char *name = dentry->d_name.name;
999 int namelen = dentry->d_name.len;
1000 int err;
1001 struct ext4_dir_entry_2 *de;
1002
1003 err = ext4_find_dest_de(dir, inode, iloc->bh,
1004 inline_start, inline_size,
1005 name, namelen, &de);
1006 if (err)
1007 return err;
1008
1009 BUFFER_TRACE(iloc->bh, "get_write_access");
1010 err = ext4_journal_get_write_access(handle, iloc->bh);
1011 if (err)
1012 return err;
1013 ext4_insert_dentry(inode, de, inline_size, name, namelen);
1014
1015 ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
1016
1017 /*
1018 * XXX shouldn't update any times until successful
1019 * completion of syscall, but too many callers depend
1020 * on this.
1021 *
1022 * XXX similarly, too many callers depend on
1023 * ext4_new_inode() setting the times, but error
1024 * recovery deletes the inode, so the worst that can
1025 * happen is that the times are slightly out of date
1026 * and/or different from the directory change time.
1027 */
1028 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
1029 ext4_update_dx_flag(dir);
1030 dir->i_version++;
1031 ext4_mark_inode_dirty(handle, dir);
1032 return 1;
1033 }
1034
1035 static void *ext4_get_inline_xattr_pos(struct inode *inode,
1036 struct ext4_iloc *iloc)
1037 {
1038 struct ext4_xattr_entry *entry;
1039 struct ext4_xattr_ibody_header *header;
1040
1041 BUG_ON(!EXT4_I(inode)->i_inline_off);
1042
1043 header = IHDR(inode, ext4_raw_inode(iloc));
1044 entry = (struct ext4_xattr_entry *)((void *)ext4_raw_inode(iloc) +
1045 EXT4_I(inode)->i_inline_off);
1046
1047 return (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs);
1048 }
1049
1050 /* Set the final de to cover the whole block. */
1051 static void ext4_update_final_de(void *de_buf, int old_size, int new_size)
1052 {
1053 struct ext4_dir_entry_2 *de, *prev_de;
1054 void *limit;
1055 int de_len;
1056
1057 de = (struct ext4_dir_entry_2 *)de_buf;
1058 if (old_size) {
1059 limit = de_buf + old_size;
1060 do {
1061 prev_de = de;
1062 de_len = ext4_rec_len_from_disk(de->rec_len, old_size);
1063 de_buf += de_len;
1064 de = (struct ext4_dir_entry_2 *)de_buf;
1065 } while (de_buf < limit);
1066
1067 prev_de->rec_len = ext4_rec_len_to_disk(de_len + new_size -
1068 old_size, new_size);
1069 } else {
1070 /* this is just created, so create an empty entry. */
1071 de->inode = 0;
1072 de->rec_len = ext4_rec_len_to_disk(new_size, new_size);
1073 }
1074 }
1075
1076 static int ext4_update_inline_dir(handle_t *handle, struct inode *dir,
1077 struct ext4_iloc *iloc)
1078 {
1079 int ret;
1080 int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
1081 int new_size = get_max_inline_xattr_value_size(dir, iloc);
1082
1083 if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
1084 return -ENOSPC;
1085
1086 ret = ext4_update_inline_data(handle, dir,
1087 new_size + EXT4_MIN_INLINE_DATA_SIZE);
1088 if (ret)
1089 return ret;
1090
1091 ext4_update_final_de(ext4_get_inline_xattr_pos(dir, iloc), old_size,
1092 EXT4_I(dir)->i_inline_size -
1093 EXT4_MIN_INLINE_DATA_SIZE);
1094 dir->i_size = EXT4_I(dir)->i_disksize = EXT4_I(dir)->i_inline_size;
1095 return 0;
1096 }
1097
1098 static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
1099 struct ext4_iloc *iloc,
1100 void *buf, int inline_size)
1101 {
1102 ext4_create_inline_data(handle, inode, inline_size);
1103 ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
1104 ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1105 }
1106
1107 static int ext4_finish_convert_inline_dir(handle_t *handle,
1108 struct inode *inode,
1109 struct buffer_head *dir_block,
1110 void *buf,
1111 int inline_size)
1112 {
1113 int err, csum_size = 0, header_size = 0;
1114 struct ext4_dir_entry_2 *de;
1115 struct ext4_dir_entry_tail *t;
1116 void *target = dir_block->b_data;
1117
1118 /*
1119 * First create "." and ".." and then copy the dir information
1120 * back to the block.
1121 */
1122 de = (struct ext4_dir_entry_2 *)target;
1123 de = ext4_init_dot_dotdot(inode, de,
1124 inode->i_sb->s_blocksize, csum_size,
1125 le32_to_cpu(((struct ext4_dir_entry_2 *)buf)->inode), 1);
1126 header_size = (void *)de - target;
1127
1128 memcpy((void *)de, buf + EXT4_INLINE_DOTDOT_SIZE,
1129 inline_size - EXT4_INLINE_DOTDOT_SIZE);
1130
1131 if (ext4_has_metadata_csum(inode->i_sb))
1132 csum_size = sizeof(struct ext4_dir_entry_tail);
1133
1134 inode->i_size = inode->i_sb->s_blocksize;
1135 i_size_write(inode, inode->i_sb->s_blocksize);
1136 EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1137 ext4_update_final_de(dir_block->b_data,
1138 inline_size - EXT4_INLINE_DOTDOT_SIZE + header_size,
1139 inode->i_sb->s_blocksize - csum_size);
1140
1141 if (csum_size) {
1142 t = EXT4_DIRENT_TAIL(dir_block->b_data,
1143 inode->i_sb->s_blocksize);
1144 initialize_dirent_tail(t, inode->i_sb->s_blocksize);
1145 }
1146 set_buffer_uptodate(dir_block);
1147 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
1148 if (err)
1149 goto out;
1150 set_buffer_verified(dir_block);
1151 out:
1152 return err;
1153 }
1154
1155 static int ext4_convert_inline_data_nolock(handle_t *handle,
1156 struct inode *inode,
1157 struct ext4_iloc *iloc)
1158 {
1159 int error;
1160 void *buf = NULL;
1161 struct buffer_head *data_bh = NULL;
1162 struct ext4_map_blocks map;
1163 int inline_size;
1164
1165 inline_size = ext4_get_inline_size(inode);
1166 buf = kmalloc(inline_size, GFP_NOFS);
1167 if (!buf) {
1168 error = -ENOMEM;
1169 goto out;
1170 }
1171
1172 error = ext4_read_inline_data(inode, buf, inline_size, iloc);
1173 if (error < 0)
1174 goto out;
1175
1176 /*
1177 * Make sure the inline directory entries pass checks before we try to
1178 * convert them, so that we avoid touching stuff that needs fsck.
1179 */
1180 if (S_ISDIR(inode->i_mode)) {
1181 error = ext4_check_all_de(inode, iloc->bh,
1182 buf + EXT4_INLINE_DOTDOT_SIZE,
1183 inline_size - EXT4_INLINE_DOTDOT_SIZE);
1184 if (error)
1185 goto out;
1186 }
1187
1188 error = ext4_destroy_inline_data_nolock(handle, inode);
1189 if (error)
1190 goto out;
1191
1192 map.m_lblk = 0;
1193 map.m_len = 1;
1194 map.m_flags = 0;
1195 error = ext4_map_blocks(handle, inode, &map, EXT4_GET_BLOCKS_CREATE);
1196 if (error < 0)
1197 goto out_restore;
1198 if (!(map.m_flags & EXT4_MAP_MAPPED)) {
1199 error = -EIO;
1200 goto out_restore;
1201 }
1202
1203 data_bh = sb_getblk(inode->i_sb, map.m_pblk);
1204 if (!data_bh) {
1205 error = -ENOMEM;
1206 goto out_restore;
1207 }
1208
1209 lock_buffer(data_bh);
1210 error = ext4_journal_get_create_access(handle, data_bh);
1211 if (error) {
1212 unlock_buffer(data_bh);
1213 error = -EIO;
1214 goto out_restore;
1215 }
1216 memset(data_bh->b_data, 0, inode->i_sb->s_blocksize);
1217
1218 if (!S_ISDIR(inode->i_mode)) {
1219 memcpy(data_bh->b_data, buf, inline_size);
1220 set_buffer_uptodate(data_bh);
1221 error = ext4_handle_dirty_metadata(handle,
1222 inode, data_bh);
1223 } else {
1224 error = ext4_finish_convert_inline_dir(handle, inode, data_bh,
1225 buf, inline_size);
1226 }
1227
1228 unlock_buffer(data_bh);
1229 out_restore:
1230 if (error)
1231 ext4_restore_inline_data(handle, inode, iloc, buf, inline_size);
1232
1233 out:
1234 brelse(data_bh);
1235 kfree(buf);
1236 return error;
1237 }
1238
1239 /*
1240 * Try to add the new entry to the inline data.
1241 * If succeeds, return 0. If not, extended the inline dir and copied data to
1242 * the new created block.
1243 */
1244 int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
1245 struct inode *inode)
1246 {
1247 int ret, inline_size;
1248 void *inline_start;
1249 struct ext4_iloc iloc;
1250 struct inode *dir = dentry->d_parent->d_inode;
1251
1252 ret = ext4_get_inode_loc(dir, &iloc);
1253 if (ret)
1254 return ret;
1255
1256 down_write(&EXT4_I(dir)->xattr_sem);
1257 if (!ext4_has_inline_data(dir))
1258 goto out;
1259
1260 inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1261 EXT4_INLINE_DOTDOT_SIZE;
1262 inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1263
1264 ret = ext4_add_dirent_to_inline(handle, dentry, inode, &iloc,
1265 inline_start, inline_size);
1266 if (ret != -ENOSPC)
1267 goto out;
1268
1269 /* check whether it can be inserted to inline xattr space. */
1270 inline_size = EXT4_I(dir)->i_inline_size -
1271 EXT4_MIN_INLINE_DATA_SIZE;
1272 if (!inline_size) {
1273 /* Try to use the xattr space.*/
1274 ret = ext4_update_inline_dir(handle, dir, &iloc);
1275 if (ret && ret != -ENOSPC)
1276 goto out;
1277
1278 inline_size = EXT4_I(dir)->i_inline_size -
1279 EXT4_MIN_INLINE_DATA_SIZE;
1280 }
1281
1282 if (inline_size) {
1283 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1284
1285 ret = ext4_add_dirent_to_inline(handle, dentry, inode, &iloc,
1286 inline_start, inline_size);
1287
1288 if (ret != -ENOSPC)
1289 goto out;
1290 }
1291
1292 /*
1293 * The inline space is filled up, so create a new block for it.
1294 * As the extent tree will be created, we have to save the inline
1295 * dir first.
1296 */
1297 ret = ext4_convert_inline_data_nolock(handle, dir, &iloc);
1298
1299 out:
1300 ext4_mark_inode_dirty(handle, dir);
1301 up_write(&EXT4_I(dir)->xattr_sem);
1302 brelse(iloc.bh);
1303 return ret;
1304 }
1305
1306 /*
1307 * This function fills a red-black tree with information from an
1308 * inlined dir. It returns the number directory entries loaded
1309 * into the tree. If there is an error it is returned in err.
1310 */
1311 int htree_inlinedir_to_tree(struct file *dir_file,
1312 struct inode *dir, ext4_lblk_t block,
1313 struct dx_hash_info *hinfo,
1314 __u32 start_hash, __u32 start_minor_hash,
1315 int *has_inline_data)
1316 {
1317 int err = 0, count = 0;
1318 unsigned int parent_ino;
1319 int pos;
1320 struct ext4_dir_entry_2 *de;
1321 struct inode *inode = file_inode(dir_file);
1322 int ret, inline_size = 0;
1323 struct ext4_iloc iloc;
1324 void *dir_buf = NULL;
1325 struct ext4_dir_entry_2 fake;
1326
1327 ret = ext4_get_inode_loc(inode, &iloc);
1328 if (ret)
1329 return ret;
1330
1331 down_read(&EXT4_I(inode)->xattr_sem);
1332 if (!ext4_has_inline_data(inode)) {
1333 up_read(&EXT4_I(inode)->xattr_sem);
1334 *has_inline_data = 0;
1335 goto out;
1336 }
1337
1338 inline_size = ext4_get_inline_size(inode);
1339 dir_buf = kmalloc(inline_size, GFP_NOFS);
1340 if (!dir_buf) {
1341 ret = -ENOMEM;
1342 up_read(&EXT4_I(inode)->xattr_sem);
1343 goto out;
1344 }
1345
1346 ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
1347 up_read(&EXT4_I(inode)->xattr_sem);
1348 if (ret < 0)
1349 goto out;
1350
1351 pos = 0;
1352 parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
1353 while (pos < inline_size) {
1354 /*
1355 * As inlined dir doesn't store any information about '.' and
1356 * only the inode number of '..' is stored, we have to handle
1357 * them differently.
1358 */
1359 if (pos == 0) {
1360 fake.inode = cpu_to_le32(inode->i_ino);
1361 fake.name_len = 1;
1362 strcpy(fake.name, ".");
1363 fake.rec_len = ext4_rec_len_to_disk(
1364 EXT4_DIR_REC_LEN(fake.name_len),
1365 inline_size);
1366 ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
1367 de = &fake;
1368 pos = EXT4_INLINE_DOTDOT_OFFSET;
1369 } else if (pos == EXT4_INLINE_DOTDOT_OFFSET) {
1370 fake.inode = cpu_to_le32(parent_ino);
1371 fake.name_len = 2;
1372 strcpy(fake.name, "..");
1373 fake.rec_len = ext4_rec_len_to_disk(
1374 EXT4_DIR_REC_LEN(fake.name_len),
1375 inline_size);
1376 ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
1377 de = &fake;
1378 pos = EXT4_INLINE_DOTDOT_SIZE;
1379 } else {
1380 de = (struct ext4_dir_entry_2 *)(dir_buf + pos);
1381 pos += ext4_rec_len_from_disk(de->rec_len, inline_size);
1382 if (ext4_check_dir_entry(inode, dir_file, de,
1383 iloc.bh, dir_buf,
1384 inline_size, pos)) {
1385 ret = count;
1386 goto out;
1387 }
1388 }
1389
1390 ext4fs_dirhash(de->name, de->name_len, hinfo);
1391 if ((hinfo->hash < start_hash) ||
1392 ((hinfo->hash == start_hash) &&
1393 (hinfo->minor_hash < start_minor_hash)))
1394 continue;
1395 if (de->inode == 0)
1396 continue;
1397 err = ext4_htree_store_dirent(dir_file,
1398 hinfo->hash, hinfo->minor_hash, de);
1399 if (err) {
1400 count = err;
1401 goto out;
1402 }
1403 count++;
1404 }
1405 ret = count;
1406 out:
1407 kfree(dir_buf);
1408 brelse(iloc.bh);
1409 return ret;
1410 }
1411
1412 /*
1413 * So this function is called when the volume is mkfsed with
1414 * dir_index disabled. In order to keep f_pos persistent
1415 * after we convert from an inlined dir to a blocked based,
1416 * we just pretend that we are a normal dir and return the
1417 * offset as if '.' and '..' really take place.
1418 *
1419 */
1420 int ext4_read_inline_dir(struct file *file,
1421 struct dir_context *ctx,
1422 int *has_inline_data)
1423 {
1424 unsigned int offset, parent_ino;
1425 int i;
1426 struct ext4_dir_entry_2 *de;
1427 struct super_block *sb;
1428 struct inode *inode = file_inode(file);
1429 int ret, inline_size = 0;
1430 struct ext4_iloc iloc;
1431 void *dir_buf = NULL;
1432 int dotdot_offset, dotdot_size, extra_offset, extra_size;
1433
1434 ret = ext4_get_inode_loc(inode, &iloc);
1435 if (ret)
1436 return ret;
1437
1438 down_read(&EXT4_I(inode)->xattr_sem);
1439 if (!ext4_has_inline_data(inode)) {
1440 up_read(&EXT4_I(inode)->xattr_sem);
1441 *has_inline_data = 0;
1442 goto out;
1443 }
1444
1445 inline_size = ext4_get_inline_size(inode);
1446 dir_buf = kmalloc(inline_size, GFP_NOFS);
1447 if (!dir_buf) {
1448 ret = -ENOMEM;
1449 up_read(&EXT4_I(inode)->xattr_sem);
1450 goto out;
1451 }
1452
1453 ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
1454 up_read(&EXT4_I(inode)->xattr_sem);
1455 if (ret < 0)
1456 goto out;
1457
1458 ret = 0;
1459 sb = inode->i_sb;
1460 parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
1461 offset = ctx->pos;
1462
1463 /*
1464 * dotdot_offset and dotdot_size is the real offset and
1465 * size for ".." and "." if the dir is block based while
1466 * the real size for them are only EXT4_INLINE_DOTDOT_SIZE.
1467 * So we will use extra_offset and extra_size to indicate them
1468 * during the inline dir iteration.
1469 */
1470 dotdot_offset = EXT4_DIR_REC_LEN(1);
1471 dotdot_size = dotdot_offset + EXT4_DIR_REC_LEN(2);
1472 extra_offset = dotdot_size - EXT4_INLINE_DOTDOT_SIZE;
1473 extra_size = extra_offset + inline_size;
1474
1475 /*
1476 * If the version has changed since the last call to
1477 * readdir(2), then we might be pointing to an invalid
1478 * dirent right now. Scan from the start of the inline
1479 * dir to make sure.
1480 */
1481 if (file->f_version != inode->i_version) {
1482 for (i = 0; i < extra_size && i < offset;) {
1483 /*
1484 * "." is with offset 0 and
1485 * ".." is dotdot_offset.
1486 */
1487 if (!i) {
1488 i = dotdot_offset;
1489 continue;
1490 } else if (i == dotdot_offset) {
1491 i = dotdot_size;
1492 continue;
1493 }
1494 /* for other entry, the real offset in
1495 * the buf has to be tuned accordingly.
1496 */
1497 de = (struct ext4_dir_entry_2 *)
1498 (dir_buf + i - extra_offset);
1499 /* It's too expensive to do a full
1500 * dirent test each time round this
1501 * loop, but we do have to test at
1502 * least that it is non-zero. A
1503 * failure will be detected in the
1504 * dirent test below. */
1505 if (ext4_rec_len_from_disk(de->rec_len, extra_size)
1506 < EXT4_DIR_REC_LEN(1))
1507 break;
1508 i += ext4_rec_len_from_disk(de->rec_len,
1509 extra_size);
1510 }
1511 offset = i;
1512 ctx->pos = offset;
1513 file->f_version = inode->i_version;
1514 }
1515
1516 while (ctx->pos < extra_size) {
1517 if (ctx->pos == 0) {
1518 if (!dir_emit(ctx, ".", 1, inode->i_ino, DT_DIR))
1519 goto out;
1520 ctx->pos = dotdot_offset;
1521 continue;
1522 }
1523
1524 if (ctx->pos == dotdot_offset) {
1525 if (!dir_emit(ctx, "..", 2, parent_ino, DT_DIR))
1526 goto out;
1527 ctx->pos = dotdot_size;
1528 continue;
1529 }
1530
1531 de = (struct ext4_dir_entry_2 *)
1532 (dir_buf + ctx->pos - extra_offset);
1533 if (ext4_check_dir_entry(inode, file, de, iloc.bh, dir_buf,
1534 extra_size, ctx->pos))
1535 goto out;
1536 if (le32_to_cpu(de->inode)) {
1537 if (!dir_emit(ctx, de->name, de->name_len,
1538 le32_to_cpu(de->inode),
1539 get_dtype(sb, de->file_type)))
1540 goto out;
1541 }
1542 ctx->pos += ext4_rec_len_from_disk(de->rec_len, extra_size);
1543 }
1544 out:
1545 kfree(dir_buf);
1546 brelse(iloc.bh);
1547 return ret;
1548 }
1549
1550 struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
1551 struct ext4_dir_entry_2 **parent_de,
1552 int *retval)
1553 {
1554 struct ext4_iloc iloc;
1555
1556 *retval = ext4_get_inode_loc(inode, &iloc);
1557 if (*retval)
1558 return NULL;
1559
1560 *parent_de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1561
1562 return iloc.bh;
1563 }
1564
1565 /*
1566 * Try to create the inline data for the new dir.
1567 * If it succeeds, return 0, otherwise return the error.
1568 * In case of ENOSPC, the caller should create the normal disk layout dir.
1569 */
1570 int ext4_try_create_inline_dir(handle_t *handle, struct inode *parent,
1571 struct inode *inode)
1572 {
1573 int ret, inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1574 struct ext4_iloc iloc;
1575 struct ext4_dir_entry_2 *de;
1576
1577 ret = ext4_get_inode_loc(inode, &iloc);
1578 if (ret)
1579 return ret;
1580
1581 ret = ext4_prepare_inline_data(handle, inode, inline_size);
1582 if (ret)
1583 goto out;
1584
1585 /*
1586 * For inline dir, we only save the inode information for the ".."
1587 * and create a fake dentry to cover the left space.
1588 */
1589 de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1590 de->inode = cpu_to_le32(parent->i_ino);
1591 de = (struct ext4_dir_entry_2 *)((void *)de + EXT4_INLINE_DOTDOT_SIZE);
1592 de->inode = 0;
1593 de->rec_len = ext4_rec_len_to_disk(
1594 inline_size - EXT4_INLINE_DOTDOT_SIZE,
1595 inline_size);
1596 set_nlink(inode, 2);
1597 inode->i_size = EXT4_I(inode)->i_disksize = inline_size;
1598 out:
1599 brelse(iloc.bh);
1600 return ret;
1601 }
1602
1603 struct buffer_head *ext4_find_inline_entry(struct inode *dir,
1604 const struct qstr *d_name,
1605 struct ext4_dir_entry_2 **res_dir,
1606 int *has_inline_data)
1607 {
1608 int ret;
1609 struct ext4_iloc iloc;
1610 void *inline_start;
1611 int inline_size;
1612
1613 if (ext4_get_inode_loc(dir, &iloc))
1614 return NULL;
1615
1616 down_read(&EXT4_I(dir)->xattr_sem);
1617 if (!ext4_has_inline_data(dir)) {
1618 *has_inline_data = 0;
1619 goto out;
1620 }
1621
1622 inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1623 EXT4_INLINE_DOTDOT_SIZE;
1624 inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1625 ret = search_dir(iloc.bh, inline_start, inline_size,
1626 dir, d_name, 0, res_dir);
1627 if (ret == 1)
1628 goto out_find;
1629 if (ret < 0)
1630 goto out;
1631
1632 if (ext4_get_inline_size(dir) == EXT4_MIN_INLINE_DATA_SIZE)
1633 goto out;
1634
1635 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1636 inline_size = ext4_get_inline_size(dir) - EXT4_MIN_INLINE_DATA_SIZE;
1637
1638 ret = search_dir(iloc.bh, inline_start, inline_size,
1639 dir, d_name, 0, res_dir);
1640 if (ret == 1)
1641 goto out_find;
1642
1643 out:
1644 brelse(iloc.bh);
1645 iloc.bh = NULL;
1646 out_find:
1647 up_read(&EXT4_I(dir)->xattr_sem);
1648 return iloc.bh;
1649 }
1650
1651 int ext4_delete_inline_entry(handle_t *handle,
1652 struct inode *dir,
1653 struct ext4_dir_entry_2 *de_del,
1654 struct buffer_head *bh,
1655 int *has_inline_data)
1656 {
1657 int err, inline_size;
1658 struct ext4_iloc iloc;
1659 void *inline_start;
1660
1661 err = ext4_get_inode_loc(dir, &iloc);
1662 if (err)
1663 return err;
1664
1665 down_write(&EXT4_I(dir)->xattr_sem);
1666 if (!ext4_has_inline_data(dir)) {
1667 *has_inline_data = 0;
1668 goto out;
1669 }
1670
1671 if ((void *)de_del - ((void *)ext4_raw_inode(&iloc)->i_block) <
1672 EXT4_MIN_INLINE_DATA_SIZE) {
1673 inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1674 EXT4_INLINE_DOTDOT_SIZE;
1675 inline_size = EXT4_MIN_INLINE_DATA_SIZE -
1676 EXT4_INLINE_DOTDOT_SIZE;
1677 } else {
1678 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1679 inline_size = ext4_get_inline_size(dir) -
1680 EXT4_MIN_INLINE_DATA_SIZE;
1681 }
1682
1683 BUFFER_TRACE(bh, "get_write_access");
1684 err = ext4_journal_get_write_access(handle, bh);
1685 if (err)
1686 goto out;
1687
1688 err = ext4_generic_delete_entry(handle, dir, de_del, bh,
1689 inline_start, inline_size, 0);
1690 if (err)
1691 goto out;
1692
1693 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
1694 err = ext4_mark_inode_dirty(handle, dir);
1695 if (unlikely(err))
1696 goto out;
1697
1698 ext4_show_inline_dir(dir, iloc.bh, inline_start, inline_size);
1699 out:
1700 up_write(&EXT4_I(dir)->xattr_sem);
1701 brelse(iloc.bh);
1702 if (err != -ENOENT)
1703 ext4_std_error(dir->i_sb, err);
1704 return err;
1705 }
1706
1707 /*
1708 * Get the inline dentry at offset.
1709 */
1710 static inline struct ext4_dir_entry_2 *
1711 ext4_get_inline_entry(struct inode *inode,
1712 struct ext4_iloc *iloc,
1713 unsigned int offset,
1714 void **inline_start,
1715 int *inline_size)
1716 {
1717 void *inline_pos;
1718
1719 BUG_ON(offset > ext4_get_inline_size(inode));
1720
1721 if (offset < EXT4_MIN_INLINE_DATA_SIZE) {
1722 inline_pos = (void *)ext4_raw_inode(iloc)->i_block;
1723 *inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1724 } else {
1725 inline_pos = ext4_get_inline_xattr_pos(inode, iloc);
1726 offset -= EXT4_MIN_INLINE_DATA_SIZE;
1727 *inline_size = ext4_get_inline_size(inode) -
1728 EXT4_MIN_INLINE_DATA_SIZE;
1729 }
1730
1731 if (inline_start)
1732 *inline_start = inline_pos;
1733 return (struct ext4_dir_entry_2 *)(inline_pos + offset);
1734 }
1735
1736 int empty_inline_dir(struct inode *dir, int *has_inline_data)
1737 {
1738 int err, inline_size;
1739 struct ext4_iloc iloc;
1740 void *inline_pos;
1741 unsigned int offset;
1742 struct ext4_dir_entry_2 *de;
1743 int ret = 1;
1744
1745 err = ext4_get_inode_loc(dir, &iloc);
1746 if (err) {
1747 EXT4_ERROR_INODE(dir, "error %d getting inode %lu block",
1748 err, dir->i_ino);
1749 return 1;
1750 }
1751
1752 down_read(&EXT4_I(dir)->xattr_sem);
1753 if (!ext4_has_inline_data(dir)) {
1754 *has_inline_data = 0;
1755 goto out;
1756 }
1757
1758 de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1759 if (!le32_to_cpu(de->inode)) {
1760 ext4_warning(dir->i_sb,
1761 "bad inline directory (dir #%lu) - no `..'",
1762 dir->i_ino);
1763 ret = 1;
1764 goto out;
1765 }
1766
1767 offset = EXT4_INLINE_DOTDOT_SIZE;
1768 while (offset < dir->i_size) {
1769 de = ext4_get_inline_entry(dir, &iloc, offset,
1770 &inline_pos, &inline_size);
1771 if (ext4_check_dir_entry(dir, NULL, de,
1772 iloc.bh, inline_pos,
1773 inline_size, offset)) {
1774 ext4_warning(dir->i_sb,
1775 "bad inline directory (dir #%lu) - "
1776 "inode %u, rec_len %u, name_len %d"
1777 "inline size %d\n",
1778 dir->i_ino, le32_to_cpu(de->inode),
1779 le16_to_cpu(de->rec_len), de->name_len,
1780 inline_size);
1781 ret = 1;
1782 goto out;
1783 }
1784 if (le32_to_cpu(de->inode)) {
1785 ret = 0;
1786 goto out;
1787 }
1788 offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
1789 }
1790
1791 out:
1792 up_read(&EXT4_I(dir)->xattr_sem);
1793 brelse(iloc.bh);
1794 return ret;
1795 }
1796
1797 int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
1798 {
1799 int ret;
1800
1801 down_write(&EXT4_I(inode)->xattr_sem);
1802 ret = ext4_destroy_inline_data_nolock(handle, inode);
1803 up_write(&EXT4_I(inode)->xattr_sem);
1804
1805 return ret;
1806 }
1807
1808 int ext4_inline_data_fiemap(struct inode *inode,
1809 struct fiemap_extent_info *fieinfo,
1810 int *has_inline)
1811 {
1812 __u64 physical = 0;
1813 __u64 length;
1814 __u32 flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_LAST;
1815 int error = 0;
1816 struct ext4_iloc iloc;
1817
1818 down_read(&EXT4_I(inode)->xattr_sem);
1819 if (!ext4_has_inline_data(inode)) {
1820 *has_inline = 0;
1821 goto out;
1822 }
1823
1824 error = ext4_get_inode_loc(inode, &iloc);
1825 if (error)
1826 goto out;
1827
1828 physical = (__u64)iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
1829 physical += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
1830 physical += offsetof(struct ext4_inode, i_block);
1831 length = i_size_read(inode);
1832
1833 if (physical)
1834 error = fiemap_fill_next_extent(fieinfo, 0, physical,
1835 length, flags);
1836 brelse(iloc.bh);
1837 out:
1838 up_read(&EXT4_I(inode)->xattr_sem);
1839 return (error < 0 ? error : 0);
1840 }
1841
1842 /*
1843 * Called during xattr set, and if we can sparse space 'needed',
1844 * just create the extent tree evict the data to the outer block.
1845 *
1846 * We use jbd2 instead of page cache to move data to the 1st block
1847 * so that the whole transaction can be committed as a whole and
1848 * the data isn't lost because of the delayed page cache write.
1849 */
1850 int ext4_try_to_evict_inline_data(handle_t *handle,
1851 struct inode *inode,
1852 int needed)
1853 {
1854 int error;
1855 struct ext4_xattr_entry *entry;
1856 struct ext4_inode *raw_inode;
1857 struct ext4_iloc iloc;
1858
1859 error = ext4_get_inode_loc(inode, &iloc);
1860 if (error)
1861 return error;
1862
1863 raw_inode = ext4_raw_inode(&iloc);
1864 entry = (struct ext4_xattr_entry *)((void *)raw_inode +
1865 EXT4_I(inode)->i_inline_off);
1866 if (EXT4_XATTR_LEN(entry->e_name_len) +
1867 EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)) < needed) {
1868 error = -ENOSPC;
1869 goto out;
1870 }
1871
1872 error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
1873 out:
1874 brelse(iloc.bh);
1875 return error;
1876 }
1877
1878 void ext4_inline_data_truncate(struct inode *inode, int *has_inline)
1879 {
1880 handle_t *handle;
1881 int inline_size, value_len, needed_blocks;
1882 size_t i_size;
1883 void *value = NULL;
1884 struct ext4_xattr_ibody_find is = {
1885 .s = { .not_found = -ENODATA, },
1886 };
1887 struct ext4_xattr_info i = {
1888 .name_index = EXT4_XATTR_INDEX_SYSTEM,
1889 .name = EXT4_XATTR_SYSTEM_DATA,
1890 };
1891
1892
1893 needed_blocks = ext4_writepage_trans_blocks(inode);
1894 handle = ext4_journal_start(inode, EXT4_HT_INODE, needed_blocks);
1895 if (IS_ERR(handle))
1896 return;
1897
1898 down_write(&EXT4_I(inode)->xattr_sem);
1899 if (!ext4_has_inline_data(inode)) {
1900 *has_inline = 0;
1901 ext4_journal_stop(handle);
1902 return;
1903 }
1904
1905 if (ext4_orphan_add(handle, inode))
1906 goto out;
1907
1908 if (ext4_get_inode_loc(inode, &is.iloc))
1909 goto out;
1910
1911 down_write(&EXT4_I(inode)->i_data_sem);
1912 i_size = inode->i_size;
1913 inline_size = ext4_get_inline_size(inode);
1914 EXT4_I(inode)->i_disksize = i_size;
1915
1916 if (i_size < inline_size) {
1917 /* Clear the content in the xattr space. */
1918 if (inline_size > EXT4_MIN_INLINE_DATA_SIZE) {
1919 if (ext4_xattr_ibody_find(inode, &i, &is))
1920 goto out_error;
1921
1922 BUG_ON(is.s.not_found);
1923
1924 value_len = le32_to_cpu(is.s.here->e_value_size);
1925 value = kmalloc(value_len, GFP_NOFS);
1926 if (!value)
1927 goto out_error;
1928
1929 if (ext4_xattr_ibody_get(inode, i.name_index, i.name,
1930 value, value_len))
1931 goto out_error;
1932
1933 i.value = value;
1934 i.value_len = i_size > EXT4_MIN_INLINE_DATA_SIZE ?
1935 i_size - EXT4_MIN_INLINE_DATA_SIZE : 0;
1936 if (ext4_xattr_ibody_inline_set(handle, inode, &i, &is))
1937 goto out_error;
1938 }
1939
1940 /* Clear the content within i_blocks. */
1941 if (i_size < EXT4_MIN_INLINE_DATA_SIZE) {
1942 void *p = (void *) ext4_raw_inode(&is.iloc)->i_block;
1943 memset(p + i_size, 0,
1944 EXT4_MIN_INLINE_DATA_SIZE - i_size);
1945 }
1946
1947 EXT4_I(inode)->i_inline_size = i_size <
1948 EXT4_MIN_INLINE_DATA_SIZE ?
1949 EXT4_MIN_INLINE_DATA_SIZE : i_size;
1950 }
1951
1952 out_error:
1953 up_write(&EXT4_I(inode)->i_data_sem);
1954 out:
1955 brelse(is.iloc.bh);
1956 up_write(&EXT4_I(inode)->xattr_sem);
1957 kfree(value);
1958 if (inode->i_nlink)
1959 ext4_orphan_del(handle, inode);
1960
1961 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
1962 ext4_mark_inode_dirty(handle, inode);
1963 if (IS_SYNC(inode))
1964 ext4_handle_sync(handle);
1965
1966 ext4_journal_stop(handle);
1967 return;
1968 }
1969
1970 int ext4_convert_inline_data(struct inode *inode)
1971 {
1972 int error, needed_blocks;
1973 handle_t *handle;
1974 struct ext4_iloc iloc;
1975
1976 if (!ext4_has_inline_data(inode)) {
1977 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1978 return 0;
1979 }
1980
1981 needed_blocks = ext4_writepage_trans_blocks(inode);
1982
1983 iloc.bh = NULL;
1984 error = ext4_get_inode_loc(inode, &iloc);
1985 if (error)
1986 return error;
1987
1988 handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
1989 if (IS_ERR(handle)) {
1990 error = PTR_ERR(handle);
1991 goto out_free;
1992 }
1993
1994 down_write(&EXT4_I(inode)->xattr_sem);
1995 if (!ext4_has_inline_data(inode)) {
1996 up_write(&EXT4_I(inode)->xattr_sem);
1997 goto out;
1998 }
1999
2000 error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
2001 up_write(&EXT4_I(inode)->xattr_sem);
2002 out:
2003 ext4_journal_stop(handle);
2004 out_free:
2005 brelse(iloc.bh);
2006 return error;
2007 }
Linux kernel - Deliverables
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