1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53#include <linux/init.h>
54#include <linux/fs.h>
55#include <linux/slab.h>
56#include <linux/mbcache.h>
57#include <linux/quotaops.h>
58#include "ext4_jbd2.h"
59#include "ext4.h"
60#include "xattr.h"
61#include "acl.h"
62
63#ifdef EXT4_XATTR_DEBUG
64# define ea_idebug(inode, f...) do { \
65 printk(KERN_DEBUG "inode %s:%lu: ", \
66 inode->i_sb->s_id, inode->i_ino); \
67 printk(f); \
68 printk("\n"); \
69 } while (0)
70# define ea_bdebug(bh, f...) do { \
71 printk(KERN_DEBUG "block %pg:%lu: ", \
72 bh->b_bdev, (unsigned long) bh->b_blocknr); \
73 printk(f); \
74 printk("\n"); \
75 } while (0)
76#else
77# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
78# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
79#endif
80
81static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *);
82static struct buffer_head *ext4_xattr_cache_find(struct inode *,
83 struct ext4_xattr_header *,
84 struct mb_cache_entry **);
85static void ext4_xattr_rehash(struct ext4_xattr_header *,
86 struct ext4_xattr_entry *);
87static int ext4_xattr_list(struct dentry *dentry, char *buffer,
88 size_t buffer_size);
89
90static const struct xattr_handler *ext4_xattr_handler_map[] = {
91 [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler,
92#ifdef CONFIG_EXT4_FS_POSIX_ACL
93 [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
94 [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
95#endif
96 [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler,
97#ifdef CONFIG_EXT4_FS_SECURITY
98 [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler,
99#endif
100};
101
102const struct xattr_handler *ext4_xattr_handlers[] = {
103 &ext4_xattr_user_handler,
104 &ext4_xattr_trusted_handler,
105#ifdef CONFIG_EXT4_FS_POSIX_ACL
106 &posix_acl_access_xattr_handler,
107 &posix_acl_default_xattr_handler,
108#endif
109#ifdef CONFIG_EXT4_FS_SECURITY
110 &ext4_xattr_security_handler,
111#endif
112 NULL
113};
114
115#define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \
116 inode->i_sb->s_fs_info)->s_mb_cache)
117
118static __le32 ext4_xattr_block_csum(struct inode *inode,
119 sector_t block_nr,
120 struct ext4_xattr_header *hdr)
121{
122 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
123 __u32 csum;
124 __le32 save_csum;
125 __le64 dsk_block_nr = cpu_to_le64(block_nr);
126
127 save_csum = hdr->h_checksum;
128 hdr->h_checksum = 0;
129 csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr,
130 sizeof(dsk_block_nr));
131 csum = ext4_chksum(sbi, csum, (__u8 *)hdr,
132 EXT4_BLOCK_SIZE(inode->i_sb));
133
134 hdr->h_checksum = save_csum;
135 return cpu_to_le32(csum);
136}
137
138static int ext4_xattr_block_csum_verify(struct inode *inode,
139 sector_t block_nr,
140 struct ext4_xattr_header *hdr)
141{
142 if (ext4_has_metadata_csum(inode->i_sb) &&
143 (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr)))
144 return 0;
145 return 1;
146}
147
148static void ext4_xattr_block_csum_set(struct inode *inode,
149 sector_t block_nr,
150 struct ext4_xattr_header *hdr)
151{
152 if (!ext4_has_metadata_csum(inode->i_sb))
153 return;
154
155 hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr);
156}
157
158static inline int ext4_handle_dirty_xattr_block(handle_t *handle,
159 struct inode *inode,
160 struct buffer_head *bh)
161{
162 ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh));
163 return ext4_handle_dirty_metadata(handle, inode, bh);
164}
165
166static inline const struct xattr_handler *
167ext4_xattr_handler(int name_index)
168{
169 const struct xattr_handler *handler = NULL;
170
171 if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
172 handler = ext4_xattr_handler_map[name_index];
173 return handler;
174}
175
176
177
178
179
180
181ssize_t
182ext4_listxattr(struct dentry *dentry, char *buffer, size_t size)
183{
184 return ext4_xattr_list(dentry, buffer, size);
185}
186
187static int
188ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end,
189 void *value_start)
190{
191 struct ext4_xattr_entry *e = entry;
192
193 while (!IS_LAST_ENTRY(e)) {
194 struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e);
195 if ((void *)next >= end)
196 return -EFSCORRUPTED;
197 e = next;
198 }
199
200 while (!IS_LAST_ENTRY(entry)) {
201 if (entry->e_value_size != 0 &&
202 (value_start + le16_to_cpu(entry->e_value_offs) <
203 (void *)e + sizeof(__u32) ||
204 value_start + le16_to_cpu(entry->e_value_offs) +
205 le32_to_cpu(entry->e_value_size) > end))
206 return -EFSCORRUPTED;
207 entry = EXT4_XATTR_NEXT(entry);
208 }
209
210 return 0;
211}
212
213static inline int
214ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh)
215{
216 int error;
217
218 if (buffer_verified(bh))
219 return 0;
220
221 if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
222 BHDR(bh)->h_blocks != cpu_to_le32(1))
223 return -EFSCORRUPTED;
224 if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh)))
225 return -EFSBADCRC;
226 error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size,
227 bh->b_data);
228 if (!error)
229 set_buffer_verified(bh);
230 return error;
231}
232
233static int
234__xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header,
235 void *end, const char *function, unsigned int line)
236{
237 struct ext4_xattr_entry *entry = IFIRST(header);
238 int error = -EFSCORRUPTED;
239
240 if (((void *) header >= end) ||
241 (header->h_magic != le32_to_cpu(EXT4_XATTR_MAGIC)))
242 goto errout;
243 error = ext4_xattr_check_names(entry, end, entry);
244errout:
245 if (error)
246 __ext4_error_inode(inode, function, line, 0,
247 "corrupted in-inode xattr");
248 return error;
249}
250
251#define xattr_check_inode(inode, header, end) \
252 __xattr_check_inode((inode), (header), (end), __func__, __LINE__)
253
254static inline int
255ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size)
256{
257 size_t value_size = le32_to_cpu(entry->e_value_size);
258
259 if (entry->e_value_block != 0 || value_size > size ||
260 le16_to_cpu(entry->e_value_offs) + value_size > size)
261 return -EFSCORRUPTED;
262 return 0;
263}
264
265static int
266ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index,
267 const char *name, size_t size, int sorted)
268{
269 struct ext4_xattr_entry *entry;
270 size_t name_len;
271 int cmp = 1;
272
273 if (name == NULL)
274 return -EINVAL;
275 name_len = strlen(name);
276 entry = *pentry;
277 for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
278 cmp = name_index - entry->e_name_index;
279 if (!cmp)
280 cmp = name_len - entry->e_name_len;
281 if (!cmp)
282 cmp = memcmp(name, entry->e_name, name_len);
283 if (cmp <= 0 && (sorted || cmp == 0))
284 break;
285 }
286 *pentry = entry;
287 if (!cmp && ext4_xattr_check_entry(entry, size))
288 return -EFSCORRUPTED;
289 return cmp ? -ENODATA : 0;
290}
291
292static int
293ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
294 void *buffer, size_t buffer_size)
295{
296 struct buffer_head *bh = NULL;
297 struct ext4_xattr_entry *entry;
298 size_t size;
299 int error;
300 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
301
302 ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
303 name_index, name, buffer, (long)buffer_size);
304
305 error = -ENODATA;
306 if (!EXT4_I(inode)->i_file_acl)
307 goto cleanup;
308 ea_idebug(inode, "reading block %llu",
309 (unsigned long long)EXT4_I(inode)->i_file_acl);
310 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
311 if (!bh)
312 goto cleanup;
313 ea_bdebug(bh, "b_count=%d, refcount=%d",
314 atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
315 if (ext4_xattr_check_block(inode, bh)) {
316bad_block:
317 EXT4_ERROR_INODE(inode, "bad block %llu",
318 EXT4_I(inode)->i_file_acl);
319 error = -EFSCORRUPTED;
320 goto cleanup;
321 }
322 ext4_xattr_cache_insert(ext4_mb_cache, bh);
323 entry = BFIRST(bh);
324 error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1);
325 if (error == -EFSCORRUPTED)
326 goto bad_block;
327 if (error)
328 goto cleanup;
329 size = le32_to_cpu(entry->e_value_size);
330 if (buffer) {
331 error = -ERANGE;
332 if (size > buffer_size)
333 goto cleanup;
334 memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
335 size);
336 }
337 error = size;
338
339cleanup:
340 brelse(bh);
341 return error;
342}
343
344int
345ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
346 void *buffer, size_t buffer_size)
347{
348 struct ext4_xattr_ibody_header *header;
349 struct ext4_xattr_entry *entry;
350 struct ext4_inode *raw_inode;
351 struct ext4_iloc iloc;
352 size_t size;
353 void *end;
354 int error;
355
356 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
357 return -ENODATA;
358 error = ext4_get_inode_loc(inode, &iloc);
359 if (error)
360 return error;
361 raw_inode = ext4_raw_inode(&iloc);
362 header = IHDR(inode, raw_inode);
363 entry = IFIRST(header);
364 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
365 error = xattr_check_inode(inode, header, end);
366 if (error)
367 goto cleanup;
368 error = ext4_xattr_find_entry(&entry, name_index, name,
369 end - (void *)entry, 0);
370 if (error)
371 goto cleanup;
372 size = le32_to_cpu(entry->e_value_size);
373 if (buffer) {
374 error = -ERANGE;
375 if (size > buffer_size)
376 goto cleanup;
377 memcpy(buffer, (void *)IFIRST(header) +
378 le16_to_cpu(entry->e_value_offs), size);
379 }
380 error = size;
381
382cleanup:
383 brelse(iloc.bh);
384 return error;
385}
386
387
388
389
390
391
392
393
394
395
396
397int
398ext4_xattr_get(struct inode *inode, int name_index, const char *name,
399 void *buffer, size_t buffer_size)
400{
401 int error;
402
403 if (strlen(name) > 255)
404 return -ERANGE;
405
406 down_read(&EXT4_I(inode)->xattr_sem);
407 error = ext4_xattr_ibody_get(inode, name_index, name, buffer,
408 buffer_size);
409 if (error == -ENODATA)
410 error = ext4_xattr_block_get(inode, name_index, name, buffer,
411 buffer_size);
412 up_read(&EXT4_I(inode)->xattr_sem);
413 return error;
414}
415
416static int
417ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry,
418 char *buffer, size_t buffer_size)
419{
420 size_t rest = buffer_size;
421
422 for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
423 const struct xattr_handler *handler =
424 ext4_xattr_handler(entry->e_name_index);
425
426 if (handler && (!handler->list || handler->list(dentry))) {
427 const char *prefix = handler->prefix ?: handler->name;
428 size_t prefix_len = strlen(prefix);
429 size_t size = prefix_len + entry->e_name_len + 1;
430
431 if (buffer) {
432 if (size > rest)
433 return -ERANGE;
434 memcpy(buffer, prefix, prefix_len);
435 buffer += prefix_len;
436 memcpy(buffer, entry->e_name, entry->e_name_len);
437 buffer += entry->e_name_len;
438 *buffer++ = 0;
439 }
440 rest -= size;
441 }
442 }
443 return buffer_size - rest;
444}
445
446static int
447ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size)
448{
449 struct inode *inode = d_inode(dentry);
450 struct buffer_head *bh = NULL;
451 int error;
452 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
453
454 ea_idebug(inode, "buffer=%p, buffer_size=%ld",
455 buffer, (long)buffer_size);
456
457 error = 0;
458 if (!EXT4_I(inode)->i_file_acl)
459 goto cleanup;
460 ea_idebug(inode, "reading block %llu",
461 (unsigned long long)EXT4_I(inode)->i_file_acl);
462 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
463 error = -EIO;
464 if (!bh)
465 goto cleanup;
466 ea_bdebug(bh, "b_count=%d, refcount=%d",
467 atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
468 if (ext4_xattr_check_block(inode, bh)) {
469 EXT4_ERROR_INODE(inode, "bad block %llu",
470 EXT4_I(inode)->i_file_acl);
471 error = -EFSCORRUPTED;
472 goto cleanup;
473 }
474 ext4_xattr_cache_insert(ext4_mb_cache, bh);
475 error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size);
476
477cleanup:
478 brelse(bh);
479
480 return error;
481}
482
483static int
484ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size)
485{
486 struct inode *inode = d_inode(dentry);
487 struct ext4_xattr_ibody_header *header;
488 struct ext4_inode *raw_inode;
489 struct ext4_iloc iloc;
490 void *end;
491 int error;
492
493 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
494 return 0;
495 error = ext4_get_inode_loc(inode, &iloc);
496 if (error)
497 return error;
498 raw_inode = ext4_raw_inode(&iloc);
499 header = IHDR(inode, raw_inode);
500 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
501 error = xattr_check_inode(inode, header, end);
502 if (error)
503 goto cleanup;
504 error = ext4_xattr_list_entries(dentry, IFIRST(header),
505 buffer, buffer_size);
506
507cleanup:
508 brelse(iloc.bh);
509 return error;
510}
511
512
513
514
515
516
517
518
519
520
521
522static int
523ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
524{
525 int ret, ret2;
526
527 down_read(&EXT4_I(d_inode(dentry))->xattr_sem);
528 ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size);
529 if (ret < 0)
530 goto errout;
531 if (buffer) {
532 buffer += ret;
533 buffer_size -= ret;
534 }
535 ret = ext4_xattr_block_list(dentry, buffer, buffer_size);
536 if (ret < 0)
537 goto errout;
538 ret += ret2;
539errout:
540 up_read(&EXT4_I(d_inode(dentry))->xattr_sem);
541 return ret;
542}
543
544
545
546
547
548static void ext4_xattr_update_super_block(handle_t *handle,
549 struct super_block *sb)
550{
551 if (ext4_has_feature_xattr(sb))
552 return;
553
554 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
555 if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) {
556 ext4_set_feature_xattr(sb);
557 ext4_handle_dirty_super(handle, sb);
558 }
559}
560
561
562
563
564
565static void
566ext4_xattr_release_block(handle_t *handle, struct inode *inode,
567 struct buffer_head *bh)
568{
569 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
570 u32 hash, ref;
571 int error = 0;
572
573 BUFFER_TRACE(bh, "get_write_access");
574 error = ext4_journal_get_write_access(handle, bh);
575 if (error)
576 goto out;
577
578 lock_buffer(bh);
579 hash = le32_to_cpu(BHDR(bh)->h_hash);
580 ref = le32_to_cpu(BHDR(bh)->h_refcount);
581 if (ref == 1) {
582 ea_bdebug(bh, "refcount now=0; freeing");
583
584
585
586
587 mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr);
588 get_bh(bh);
589 unlock_buffer(bh);
590 ext4_free_blocks(handle, inode, bh, 0, 1,
591 EXT4_FREE_BLOCKS_METADATA |
592 EXT4_FREE_BLOCKS_FORGET);
593 } else {
594 ref--;
595 BHDR(bh)->h_refcount = cpu_to_le32(ref);
596 if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) {
597 struct mb_cache_entry *ce;
598
599 ce = mb_cache_entry_get(ext4_mb_cache, hash,
600 bh->b_blocknr);
601 if (ce) {
602 ce->e_reusable = 1;
603 mb_cache_entry_put(ext4_mb_cache, ce);
604 }
605 }
606
607
608
609
610
611
612
613
614
615
616
617 if (ext4_handle_valid(handle))
618 error = ext4_handle_dirty_xattr_block(handle, inode,
619 bh);
620 unlock_buffer(bh);
621 if (!ext4_handle_valid(handle))
622 error = ext4_handle_dirty_xattr_block(handle, inode,
623 bh);
624 if (IS_SYNC(inode))
625 ext4_handle_sync(handle);
626 dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1));
627 ea_bdebug(bh, "refcount now=%d; releasing",
628 le32_to_cpu(BHDR(bh)->h_refcount));
629 }
630out:
631 ext4_std_error(inode->i_sb, error);
632 return;
633}
634
635
636
637
638
639static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
640 size_t *min_offs, void *base, int *total)
641{
642 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
643 if (!last->e_value_block && last->e_value_size) {
644 size_t offs = le16_to_cpu(last->e_value_offs);
645 if (offs < *min_offs)
646 *min_offs = offs;
647 }
648 if (total)
649 *total += EXT4_XATTR_LEN(last->e_name_len);
650 }
651 return (*min_offs - ((void *)last - base) - sizeof(__u32));
652}
653
654static int
655ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
656{
657 struct ext4_xattr_entry *last;
658 size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
659
660
661 last = s->first;
662 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
663 if (!last->e_value_block && last->e_value_size) {
664 size_t offs = le16_to_cpu(last->e_value_offs);
665 if (offs < min_offs)
666 min_offs = offs;
667 }
668 }
669 free = min_offs - ((void *)last - s->base) - sizeof(__u32);
670 if (!s->not_found) {
671 if (!s->here->e_value_block && s->here->e_value_size) {
672 size_t size = le32_to_cpu(s->here->e_value_size);
673 free += EXT4_XATTR_SIZE(size);
674 }
675 free += EXT4_XATTR_LEN(name_len);
676 }
677 if (i->value) {
678 if (free < EXT4_XATTR_LEN(name_len) +
679 EXT4_XATTR_SIZE(i->value_len))
680 return -ENOSPC;
681 }
682
683 if (i->value && s->not_found) {
684
685 size_t size = EXT4_XATTR_LEN(name_len);
686 size_t rest = (void *)last - (void *)s->here + sizeof(__u32);
687 memmove((void *)s->here + size, s->here, rest);
688 memset(s->here, 0, size);
689 s->here->e_name_index = i->name_index;
690 s->here->e_name_len = name_len;
691 memcpy(s->here->e_name, i->name, name_len);
692 } else {
693 if (!s->here->e_value_block && s->here->e_value_size) {
694 void *first_val = s->base + min_offs;
695 size_t offs = le16_to_cpu(s->here->e_value_offs);
696 void *val = s->base + offs;
697 size_t size = EXT4_XATTR_SIZE(
698 le32_to_cpu(s->here->e_value_size));
699
700 if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) {
701
702
703 s->here->e_value_size =
704 cpu_to_le32(i->value_len);
705 if (i->value == EXT4_ZERO_XATTR_VALUE) {
706 memset(val, 0, size);
707 } else {
708
709 memset(val + size - EXT4_XATTR_PAD, 0,
710 EXT4_XATTR_PAD);
711 memcpy(val, i->value, i->value_len);
712 }
713 return 0;
714 }
715
716
717 memmove(first_val + size, first_val, val - first_val);
718 memset(first_val, 0, size);
719 s->here->e_value_size = 0;
720 s->here->e_value_offs = 0;
721 min_offs += size;
722
723
724 last = s->first;
725 while (!IS_LAST_ENTRY(last)) {
726 size_t o = le16_to_cpu(last->e_value_offs);
727 if (!last->e_value_block &&
728 last->e_value_size && o < offs)
729 last->e_value_offs =
730 cpu_to_le16(o + size);
731 last = EXT4_XATTR_NEXT(last);
732 }
733 }
734 if (!i->value) {
735
736 size_t size = EXT4_XATTR_LEN(name_len);
737 last = ENTRY((void *)last - size);
738 memmove(s->here, (void *)s->here + size,
739 (void *)last - (void *)s->here + sizeof(__u32));
740 memset(last, 0, size);
741 }
742 }
743
744 if (i->value) {
745
746 s->here->e_value_size = cpu_to_le32(i->value_len);
747 if (i->value_len) {
748 size_t size = EXT4_XATTR_SIZE(i->value_len);
749 void *val = s->base + min_offs - size;
750 s->here->e_value_offs = cpu_to_le16(min_offs - size);
751 if (i->value == EXT4_ZERO_XATTR_VALUE) {
752 memset(val, 0, size);
753 } else {
754
755 memset(val + size - EXT4_XATTR_PAD, 0,
756 EXT4_XATTR_PAD);
757 memcpy(val, i->value, i->value_len);
758 }
759 }
760 }
761 return 0;
762}
763
764struct ext4_xattr_block_find {
765 struct ext4_xattr_search s;
766 struct buffer_head *bh;
767};
768
769static int
770ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i,
771 struct ext4_xattr_block_find *bs)
772{
773 struct super_block *sb = inode->i_sb;
774 int error;
775
776 ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
777 i->name_index, i->name, i->value, (long)i->value_len);
778
779 if (EXT4_I(inode)->i_file_acl) {
780
781 bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl);
782 error = -EIO;
783 if (!bs->bh)
784 goto cleanup;
785 ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
786 atomic_read(&(bs->bh->b_count)),
787 le32_to_cpu(BHDR(bs->bh)->h_refcount));
788 if (ext4_xattr_check_block(inode, bs->bh)) {
789 EXT4_ERROR_INODE(inode, "bad block %llu",
790 EXT4_I(inode)->i_file_acl);
791 error = -EFSCORRUPTED;
792 goto cleanup;
793 }
794
795 bs->s.base = BHDR(bs->bh);
796 bs->s.first = BFIRST(bs->bh);
797 bs->s.end = bs->bh->b_data + bs->bh->b_size;
798 bs->s.here = bs->s.first;
799 error = ext4_xattr_find_entry(&bs->s.here, i->name_index,
800 i->name, bs->bh->b_size, 1);
801 if (error && error != -ENODATA)
802 goto cleanup;
803 bs->s.not_found = error;
804 }
805 error = 0;
806
807cleanup:
808 return error;
809}
810
811static int
812ext4_xattr_block_set(handle_t *handle, struct inode *inode,
813 struct ext4_xattr_info *i,
814 struct ext4_xattr_block_find *bs)
815{
816 struct super_block *sb = inode->i_sb;
817 struct buffer_head *new_bh = NULL;
818 struct ext4_xattr_search *s = &bs->s;
819 struct mb_cache_entry *ce = NULL;
820 int error = 0;
821 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
822
823#define header(x) ((struct ext4_xattr_header *)(x))
824
825 if (i->value && i->value_len > sb->s_blocksize)
826 return -ENOSPC;
827 if (s->base) {
828 BUFFER_TRACE(bs->bh, "get_write_access");
829 error = ext4_journal_get_write_access(handle, bs->bh);
830 if (error)
831 goto cleanup;
832 lock_buffer(bs->bh);
833
834 if (header(s->base)->h_refcount == cpu_to_le32(1)) {
835 __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash);
836
837
838
839
840
841
842 mb_cache_entry_delete_block(ext4_mb_cache, hash,
843 bs->bh->b_blocknr);
844 ea_bdebug(bs->bh, "modifying in-place");
845 error = ext4_xattr_set_entry(i, s);
846 if (!error) {
847 if (!IS_LAST_ENTRY(s->first))
848 ext4_xattr_rehash(header(s->base),
849 s->here);
850 ext4_xattr_cache_insert(ext4_mb_cache,
851 bs->bh);
852 }
853 unlock_buffer(bs->bh);
854 if (error == -EFSCORRUPTED)
855 goto bad_block;
856 if (!error)
857 error = ext4_handle_dirty_xattr_block(handle,
858 inode,
859 bs->bh);
860 if (error)
861 goto cleanup;
862 goto inserted;
863 } else {
864 int offset = (char *)s->here - bs->bh->b_data;
865
866 unlock_buffer(bs->bh);
867 ea_bdebug(bs->bh, "cloning");
868 s->base = kmalloc(bs->bh->b_size, GFP_NOFS);
869 error = -ENOMEM;
870 if (s->base == NULL)
871 goto cleanup;
872 memcpy(s->base, BHDR(bs->bh), bs->bh->b_size);
873 s->first = ENTRY(header(s->base)+1);
874 header(s->base)->h_refcount = cpu_to_le32(1);
875 s->here = ENTRY(s->base + offset);
876 s->end = s->base + bs->bh->b_size;
877 }
878 } else {
879
880 s->base = kzalloc(sb->s_blocksize, GFP_NOFS);
881
882 error = -ENOMEM;
883 if (s->base == NULL)
884 goto cleanup;
885 header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
886 header(s->base)->h_blocks = cpu_to_le32(1);
887 header(s->base)->h_refcount = cpu_to_le32(1);
888 s->first = ENTRY(header(s->base)+1);
889 s->here = ENTRY(header(s->base)+1);
890 s->end = s->base + sb->s_blocksize;
891 }
892
893 error = ext4_xattr_set_entry(i, s);
894 if (error == -EFSCORRUPTED)
895 goto bad_block;
896 if (error)
897 goto cleanup;
898 if (!IS_LAST_ENTRY(s->first))
899 ext4_xattr_rehash(header(s->base), s->here);
900
901inserted:
902 if (!IS_LAST_ENTRY(s->first)) {
903 new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce);
904 if (new_bh) {
905
906 if (new_bh == bs->bh)
907 ea_bdebug(new_bh, "keeping");
908 else {
909 u32 ref;
910
911
912
913 error = dquot_alloc_block(inode,
914 EXT4_C2B(EXT4_SB(sb), 1));
915 if (error)
916 goto cleanup;
917 BUFFER_TRACE(new_bh, "get_write_access");
918 error = ext4_journal_get_write_access(handle,
919 new_bh);
920 if (error)
921 goto cleanup_dquot;
922 lock_buffer(new_bh);
923
924
925
926
927
928
929
930
931
932
933
934
935 if (hlist_bl_unhashed(&ce->e_hash_list) ||
936 !ce->e_reusable) {
937
938
939
940
941 unlock_buffer(new_bh);
942 dquot_free_block(inode,
943 EXT4_C2B(EXT4_SB(sb),
944 1));
945 brelse(new_bh);
946 mb_cache_entry_put(ext4_mb_cache, ce);
947 ce = NULL;
948 new_bh = NULL;
949 goto inserted;
950 }
951 ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1;
952 BHDR(new_bh)->h_refcount = cpu_to_le32(ref);
953 if (ref >= EXT4_XATTR_REFCOUNT_MAX)
954 ce->e_reusable = 0;
955 ea_bdebug(new_bh, "reusing; refcount now=%d",
956 ref);
957 unlock_buffer(new_bh);
958 error = ext4_handle_dirty_xattr_block(handle,
959 inode,
960 new_bh);
961 if (error)
962 goto cleanup_dquot;
963 }
964 mb_cache_entry_touch(ext4_mb_cache, ce);
965 mb_cache_entry_put(ext4_mb_cache, ce);
966 ce = NULL;
967 } else if (bs->bh && s->base == bs->bh->b_data) {
968
969 ea_bdebug(bs->bh, "keeping this block");
970 new_bh = bs->bh;
971 get_bh(new_bh);
972 } else {
973
974 ext4_fsblk_t goal, block;
975
976 goal = ext4_group_first_block_no(sb,
977 EXT4_I(inode)->i_block_group);
978
979
980 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
981 goal = goal & EXT4_MAX_BLOCK_FILE_PHYS;
982
983 block = ext4_new_meta_blocks(handle, inode, goal, 0,
984 NULL, &error);
985 if (error)
986 goto cleanup;
987
988 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
989 BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS);
990
991 ea_idebug(inode, "creating block %llu",
992 (unsigned long long)block);
993
994 new_bh = sb_getblk(sb, block);
995 if (unlikely(!new_bh)) {
996 error = -ENOMEM;
997getblk_failed:
998 ext4_free_blocks(handle, inode, NULL, block, 1,
999 EXT4_FREE_BLOCKS_METADATA);
1000 goto cleanup;
1001 }
1002 lock_buffer(new_bh);
1003 error = ext4_journal_get_create_access(handle, new_bh);
1004 if (error) {
1005 unlock_buffer(new_bh);
1006 error = -EIO;
1007 goto getblk_failed;
1008 }
1009 memcpy(new_bh->b_data, s->base, new_bh->b_size);
1010 set_buffer_uptodate(new_bh);
1011 unlock_buffer(new_bh);
1012 ext4_xattr_cache_insert(ext4_mb_cache, new_bh);
1013 error = ext4_handle_dirty_xattr_block(handle,
1014 inode, new_bh);
1015 if (error)
1016 goto cleanup;
1017 }
1018 }
1019
1020
1021 EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0;
1022
1023
1024 if (bs->bh && bs->bh != new_bh)
1025 ext4_xattr_release_block(handle, inode, bs->bh);
1026 error = 0;
1027
1028cleanup:
1029 if (ce)
1030 mb_cache_entry_put(ext4_mb_cache, ce);
1031 brelse(new_bh);
1032 if (!(bs->bh && s->base == bs->bh->b_data))
1033 kfree(s->base);
1034
1035 return error;
1036
1037cleanup_dquot:
1038 dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1));
1039 goto cleanup;
1040
1041bad_block:
1042 EXT4_ERROR_INODE(inode, "bad block %llu",
1043 EXT4_I(inode)->i_file_acl);
1044 goto cleanup;
1045
1046#undef header
1047}
1048
1049int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
1050 struct ext4_xattr_ibody_find *is)
1051{
1052 struct ext4_xattr_ibody_header *header;
1053 struct ext4_inode *raw_inode;
1054 int error;
1055
1056 if (EXT4_I(inode)->i_extra_isize == 0)
1057 return 0;
1058 raw_inode = ext4_raw_inode(&is->iloc);
1059 header = IHDR(inode, raw_inode);
1060 is->s.base = is->s.first = IFIRST(header);
1061 is->s.here = is->s.first;
1062 is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
1063 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
1064 error = xattr_check_inode(inode, header, is->s.end);
1065 if (error)
1066 return error;
1067
1068 error = ext4_xattr_find_entry(&is->s.here, i->name_index,
1069 i->name, is->s.end -
1070 (void *)is->s.base, 0);
1071 if (error && error != -ENODATA)
1072 return error;
1073 is->s.not_found = error;
1074 }
1075 return 0;
1076}
1077
1078int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
1079 struct ext4_xattr_info *i,
1080 struct ext4_xattr_ibody_find *is)
1081{
1082 struct ext4_xattr_ibody_header *header;
1083 struct ext4_xattr_search *s = &is->s;
1084 int error;
1085
1086 if (EXT4_I(inode)->i_extra_isize == 0)
1087 return -ENOSPC;
1088 error = ext4_xattr_set_entry(i, s);
1089 if (error) {
1090 if (error == -ENOSPC &&
1091 ext4_has_inline_data(inode)) {
1092 error = ext4_try_to_evict_inline_data(handle, inode,
1093 EXT4_XATTR_LEN(strlen(i->name) +
1094 EXT4_XATTR_SIZE(i->value_len)));
1095 if (error)
1096 return error;
1097 error = ext4_xattr_ibody_find(inode, i, is);
1098 if (error)
1099 return error;
1100 error = ext4_xattr_set_entry(i, s);
1101 }
1102 if (error)
1103 return error;
1104 }
1105 header = IHDR(inode, ext4_raw_inode(&is->iloc));
1106 if (!IS_LAST_ENTRY(s->first)) {
1107 header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
1108 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
1109 } else {
1110 header->h_magic = cpu_to_le32(0);
1111 ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
1112 }
1113 return 0;
1114}
1115
1116static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
1117 struct ext4_xattr_info *i,
1118 struct ext4_xattr_ibody_find *is)
1119{
1120 struct ext4_xattr_ibody_header *header;
1121 struct ext4_xattr_search *s = &is->s;
1122 int error;
1123
1124 if (EXT4_I(inode)->i_extra_isize == 0)
1125 return -ENOSPC;
1126 error = ext4_xattr_set_entry(i, s);
1127 if (error)
1128 return error;
1129 header = IHDR(inode, ext4_raw_inode(&is->iloc));
1130 if (!IS_LAST_ENTRY(s->first)) {
1131 header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
1132 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
1133 } else {
1134 header->h_magic = cpu_to_le32(0);
1135 ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
1136 }
1137 return 0;
1138}
1139
1140static int ext4_xattr_value_same(struct ext4_xattr_search *s,
1141 struct ext4_xattr_info *i)
1142{
1143 void *value;
1144
1145 if (le32_to_cpu(s->here->e_value_size) != i->value_len)
1146 return 0;
1147 value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs);
1148 return !memcmp(value, i->value, i->value_len);
1149}
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163int
1164ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
1165 const char *name, const void *value, size_t value_len,
1166 int flags)
1167{
1168 struct ext4_xattr_info i = {
1169 .name_index = name_index,
1170 .name = name,
1171 .value = value,
1172 .value_len = value_len,
1173
1174 };
1175 struct ext4_xattr_ibody_find is = {
1176 .s = { .not_found = -ENODATA, },
1177 };
1178 struct ext4_xattr_block_find bs = {
1179 .s = { .not_found = -ENODATA, },
1180 };
1181 unsigned long no_expand;
1182 int error;
1183
1184 if (!name)
1185 return -EINVAL;
1186 if (strlen(name) > 255)
1187 return -ERANGE;
1188 down_write(&EXT4_I(inode)->xattr_sem);
1189 no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND);
1190 ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND);
1191
1192 error = ext4_reserve_inode_write(handle, inode, &is.iloc);
1193 if (error)
1194 goto cleanup;
1195
1196 if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) {
1197 struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc);
1198 memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
1199 ext4_clear_inode_state(inode, EXT4_STATE_NEW);
1200 }
1201
1202 error = ext4_xattr_ibody_find(inode, &i, &is);
1203 if (error)
1204 goto cleanup;
1205 if (is.s.not_found)
1206 error = ext4_xattr_block_find(inode, &i, &bs);
1207 if (error)
1208 goto cleanup;
1209 if (is.s.not_found && bs.s.not_found) {
1210 error = -ENODATA;
1211 if (flags & XATTR_REPLACE)
1212 goto cleanup;
1213 error = 0;
1214 if (!value)
1215 goto cleanup;
1216 } else {
1217 error = -EEXIST;
1218 if (flags & XATTR_CREATE)
1219 goto cleanup;
1220 }
1221 if (!value) {
1222 if (!is.s.not_found)
1223 error = ext4_xattr_ibody_set(handle, inode, &i, &is);
1224 else if (!bs.s.not_found)
1225 error = ext4_xattr_block_set(handle, inode, &i, &bs);
1226 } else {
1227 error = 0;
1228
1229 if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i))
1230 goto cleanup;
1231 if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i))
1232 goto cleanup;
1233
1234 error = ext4_xattr_ibody_set(handle, inode, &i, &is);
1235 if (!error && !bs.s.not_found) {
1236 i.value = NULL;
1237 error = ext4_xattr_block_set(handle, inode, &i, &bs);
1238 } else if (error == -ENOSPC) {
1239 if (EXT4_I(inode)->i_file_acl && !bs.s.base) {
1240 error = ext4_xattr_block_find(inode, &i, &bs);
1241 if (error)
1242 goto cleanup;
1243 }
1244 error = ext4_xattr_block_set(handle, inode, &i, &bs);
1245 if (error)
1246 goto cleanup;
1247 if (!is.s.not_found) {
1248 i.value = NULL;
1249 error = ext4_xattr_ibody_set(handle, inode, &i,
1250 &is);
1251 }
1252 }
1253 }
1254 if (!error) {
1255 ext4_xattr_update_super_block(handle, inode->i_sb);
1256 inode->i_ctime = ext4_current_time(inode);
1257 if (!value)
1258 ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND);
1259 error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
1260
1261
1262
1263
1264 is.iloc.bh = NULL;
1265 if (IS_SYNC(inode))
1266 ext4_handle_sync(handle);
1267 }
1268
1269cleanup:
1270 brelse(is.iloc.bh);
1271 brelse(bs.bh);
1272 if (no_expand == 0)
1273 ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND);
1274 up_write(&EXT4_I(inode)->xattr_sem);
1275 return error;
1276}
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286int
1287ext4_xattr_set(struct inode *inode, int name_index, const char *name,
1288 const void *value, size_t value_len, int flags)
1289{
1290 handle_t *handle;
1291 int error, retries = 0;
1292 int credits = ext4_jbd2_credits_xattr(inode);
1293
1294retry:
1295 handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
1296 if (IS_ERR(handle)) {
1297 error = PTR_ERR(handle);
1298 } else {
1299 int error2;
1300
1301 error = ext4_xattr_set_handle(handle, inode, name_index, name,
1302 value, value_len, flags);
1303 error2 = ext4_journal_stop(handle);
1304 if (error == -ENOSPC &&
1305 ext4_should_retry_alloc(inode->i_sb, &retries))
1306 goto retry;
1307 if (error == 0)
1308 error = error2;
1309 }
1310
1311 return error;
1312}
1313
1314
1315
1316
1317
1318static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry,
1319 int value_offs_shift, void *to,
1320 void *from, size_t n, int blocksize)
1321{
1322 struct ext4_xattr_entry *last = entry;
1323 int new_offs;
1324
1325
1326 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
1327 if (!last->e_value_block && last->e_value_size) {
1328 new_offs = le16_to_cpu(last->e_value_offs) +
1329 value_offs_shift;
1330 BUG_ON(new_offs + le32_to_cpu(last->e_value_size)
1331 > blocksize);
1332 last->e_value_offs = cpu_to_le16(new_offs);
1333 }
1334 }
1335
1336 memmove(to, from, n);
1337}
1338
1339
1340
1341
1342
1343int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
1344 struct ext4_inode *raw_inode, handle_t *handle)
1345{
1346 struct ext4_xattr_ibody_header *header;
1347 struct ext4_xattr_entry *entry, *last, *first;
1348 struct buffer_head *bh = NULL;
1349 struct ext4_xattr_ibody_find *is = NULL;
1350 struct ext4_xattr_block_find *bs = NULL;
1351 char *buffer = NULL, *b_entry_name = NULL;
1352 size_t min_offs, free;
1353 int total_ino;
1354 void *base, *start, *end;
1355 int extra_isize = 0, error = 0, tried_min_extra_isize = 0;
1356 int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize);
1357
1358 down_write(&EXT4_I(inode)->xattr_sem);
1359retry:
1360 if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) {
1361 up_write(&EXT4_I(inode)->xattr_sem);
1362 return 0;
1363 }
1364
1365 header = IHDR(inode, raw_inode);
1366 entry = IFIRST(header);
1367
1368
1369
1370
1371
1372
1373 base = start = entry;
1374 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
1375 min_offs = end - base;
1376 last = entry;
1377 total_ino = sizeof(struct ext4_xattr_ibody_header);
1378
1379 error = xattr_check_inode(inode, header, end);
1380 if (error)
1381 goto cleanup;
1382
1383 free = ext4_xattr_free_space(last, &min_offs, base, &total_ino);
1384 if (free >= new_extra_isize) {
1385 entry = IFIRST(header);
1386 ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize
1387 - new_extra_isize, (void *)raw_inode +
1388 EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize,
1389 (void *)header, total_ino,
1390 inode->i_sb->s_blocksize);
1391 EXT4_I(inode)->i_extra_isize = new_extra_isize;
1392 error = 0;
1393 goto cleanup;
1394 }
1395
1396
1397
1398
1399
1400 if (EXT4_I(inode)->i_file_acl) {
1401 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
1402 error = -EIO;
1403 if (!bh)
1404 goto cleanup;
1405 if (ext4_xattr_check_block(inode, bh)) {
1406 EXT4_ERROR_INODE(inode, "bad block %llu",
1407 EXT4_I(inode)->i_file_acl);
1408 error = -EFSCORRUPTED;
1409 goto cleanup;
1410 }
1411 base = BHDR(bh);
1412 first = BFIRST(bh);
1413 end = bh->b_data + bh->b_size;
1414 min_offs = end - base;
1415 free = ext4_xattr_free_space(first, &min_offs, base, NULL);
1416 if (free < new_extra_isize) {
1417 if (!tried_min_extra_isize && s_min_extra_isize) {
1418 tried_min_extra_isize++;
1419 new_extra_isize = s_min_extra_isize;
1420 brelse(bh);
1421 goto retry;
1422 }
1423 error = -1;
1424 goto cleanup;
1425 }
1426 } else {
1427 free = inode->i_sb->s_blocksize;
1428 }
1429
1430 while (new_extra_isize > 0) {
1431 size_t offs, size, entry_size;
1432 struct ext4_xattr_entry *small_entry = NULL;
1433 struct ext4_xattr_info i = {
1434 .value = NULL,
1435 .value_len = 0,
1436 };
1437 unsigned int total_size;
1438 unsigned int shift_bytes;
1439 unsigned int min_total_size = ~0U;
1440
1441 is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS);
1442 bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS);
1443 if (!is || !bs) {
1444 error = -ENOMEM;
1445 goto cleanup;
1446 }
1447
1448 is->s.not_found = -ENODATA;
1449 bs->s.not_found = -ENODATA;
1450 is->iloc.bh = NULL;
1451 bs->bh = NULL;
1452
1453 last = IFIRST(header);
1454
1455 entry = NULL;
1456 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
1457 total_size =
1458 EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) +
1459 EXT4_XATTR_LEN(last->e_name_len);
1460 if (total_size <= free && total_size < min_total_size) {
1461 if (total_size < new_extra_isize) {
1462 small_entry = last;
1463 } else {
1464 entry = last;
1465 min_total_size = total_size;
1466 }
1467 }
1468 }
1469
1470 if (entry == NULL) {
1471 if (small_entry) {
1472 entry = small_entry;
1473 } else {
1474 if (!tried_min_extra_isize &&
1475 s_min_extra_isize) {
1476 tried_min_extra_isize++;
1477 new_extra_isize = s_min_extra_isize;
1478 kfree(is); is = NULL;
1479 kfree(bs); bs = NULL;
1480 brelse(bh);
1481 goto retry;
1482 }
1483 error = -1;
1484 goto cleanup;
1485 }
1486 }
1487 offs = le16_to_cpu(entry->e_value_offs);
1488 size = le32_to_cpu(entry->e_value_size);
1489 entry_size = EXT4_XATTR_LEN(entry->e_name_len);
1490 i.name_index = entry->e_name_index,
1491 buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS);
1492 b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS);
1493 if (!buffer || !b_entry_name) {
1494 error = -ENOMEM;
1495 goto cleanup;
1496 }
1497
1498 memcpy(buffer, (void *)IFIRST(header) + offs,
1499 EXT4_XATTR_SIZE(size));
1500 memcpy(b_entry_name, entry->e_name, entry->e_name_len);
1501 b_entry_name[entry->e_name_len] = '\0';
1502 i.name = b_entry_name;
1503
1504 error = ext4_get_inode_loc(inode, &is->iloc);
1505 if (error)
1506 goto cleanup;
1507
1508 error = ext4_xattr_ibody_find(inode, &i, is);
1509 if (error)
1510 goto cleanup;
1511
1512
1513 error = ext4_xattr_ibody_set(handle, inode, &i, is);
1514 if (error)
1515 goto cleanup;
1516
1517 entry = IFIRST(header);
1518 if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize)
1519 shift_bytes = new_extra_isize;
1520 else
1521 shift_bytes = entry_size + size;
1522
1523 ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize -
1524 shift_bytes, (void *)raw_inode +
1525 EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes,
1526 (void *)header, total_ino - entry_size,
1527 inode->i_sb->s_blocksize);
1528
1529 extra_isize += shift_bytes;
1530 new_extra_isize -= shift_bytes;
1531 EXT4_I(inode)->i_extra_isize = extra_isize;
1532
1533 i.name = b_entry_name;
1534 i.value = buffer;
1535 i.value_len = size;
1536 error = ext4_xattr_block_find(inode, &i, bs);
1537 if (error)
1538 goto cleanup;
1539
1540
1541 error = ext4_xattr_block_set(handle, inode, &i, bs);
1542 if (error)
1543 goto cleanup;
1544 kfree(b_entry_name);
1545 kfree(buffer);
1546 b_entry_name = NULL;
1547 buffer = NULL;
1548 brelse(is->iloc.bh);
1549 kfree(is);
1550 kfree(bs);
1551 }
1552 brelse(bh);
1553 up_write(&EXT4_I(inode)->xattr_sem);
1554 return 0;
1555
1556cleanup:
1557 kfree(b_entry_name);
1558 kfree(buffer);
1559 if (is)
1560 brelse(is->iloc.bh);
1561 kfree(is);
1562 kfree(bs);
1563 brelse(bh);
1564 up_write(&EXT4_I(inode)->xattr_sem);
1565 return error;
1566}
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577void
1578ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
1579{
1580 struct buffer_head *bh = NULL;
1581
1582 if (!EXT4_I(inode)->i_file_acl)
1583 goto cleanup;
1584 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
1585 if (!bh) {
1586 EXT4_ERROR_INODE(inode, "block %llu read error",
1587 EXT4_I(inode)->i_file_acl);
1588 goto cleanup;
1589 }
1590 if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
1591 BHDR(bh)->h_blocks != cpu_to_le32(1)) {
1592 EXT4_ERROR_INODE(inode, "bad block %llu",
1593 EXT4_I(inode)->i_file_acl);
1594 goto cleanup;
1595 }
1596 ext4_xattr_release_block(handle, inode, bh);
1597 EXT4_I(inode)->i_file_acl = 0;
1598
1599cleanup:
1600 brelse(bh);
1601}
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611static void
1612ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh)
1613{
1614 struct ext4_xattr_header *header = BHDR(bh);
1615 __u32 hash = le32_to_cpu(header->h_hash);
1616 int reusable = le32_to_cpu(header->h_refcount) <
1617 EXT4_XATTR_REFCOUNT_MAX;
1618 int error;
1619
1620 error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash,
1621 bh->b_blocknr, reusable);
1622 if (error) {
1623 if (error == -EBUSY)
1624 ea_bdebug(bh, "already in cache");
1625 } else
1626 ea_bdebug(bh, "inserting [%x]", (int)hash);
1627}
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637static int
1638ext4_xattr_cmp(struct ext4_xattr_header *header1,
1639 struct ext4_xattr_header *header2)
1640{
1641 struct ext4_xattr_entry *entry1, *entry2;
1642
1643 entry1 = ENTRY(header1+1);
1644 entry2 = ENTRY(header2+1);
1645 while (!IS_LAST_ENTRY(entry1)) {
1646 if (IS_LAST_ENTRY(entry2))
1647 return 1;
1648 if (entry1->e_hash != entry2->e_hash ||
1649 entry1->e_name_index != entry2->e_name_index ||
1650 entry1->e_name_len != entry2->e_name_len ||
1651 entry1->e_value_size != entry2->e_value_size ||
1652 memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
1653 return 1;
1654 if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
1655 return -EFSCORRUPTED;
1656 if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
1657 (char *)header2 + le16_to_cpu(entry2->e_value_offs),
1658 le32_to_cpu(entry1->e_value_size)))
1659 return 1;
1660
1661 entry1 = EXT4_XATTR_NEXT(entry1);
1662 entry2 = EXT4_XATTR_NEXT(entry2);
1663 }
1664 if (!IS_LAST_ENTRY(entry2))
1665 return 1;
1666 return 0;
1667}
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677static struct buffer_head *
1678ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header,
1679 struct mb_cache_entry **pce)
1680{
1681 __u32 hash = le32_to_cpu(header->h_hash);
1682 struct mb_cache_entry *ce;
1683 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
1684
1685 if (!header->h_hash)
1686 return NULL;
1687 ea_idebug(inode, "looking for cached blocks [%x]", (int)hash);
1688 ce = mb_cache_entry_find_first(ext4_mb_cache, hash);
1689 while (ce) {
1690 struct buffer_head *bh;
1691
1692 bh = sb_bread(inode->i_sb, ce->e_block);
1693 if (!bh) {
1694 EXT4_ERROR_INODE(inode, "block %lu read error",
1695 (unsigned long) ce->e_block);
1696 } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) {
1697 *pce = ce;
1698 return bh;
1699 }
1700 brelse(bh);
1701 ce = mb_cache_entry_find_next(ext4_mb_cache, ce);
1702 }
1703 return NULL;
1704}
1705
1706#define NAME_HASH_SHIFT 5
1707#define VALUE_HASH_SHIFT 16
1708
1709
1710
1711
1712
1713
1714static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header,
1715 struct ext4_xattr_entry *entry)
1716{
1717 __u32 hash = 0;
1718 char *name = entry->e_name;
1719 int n;
1720
1721 for (n = 0; n < entry->e_name_len; n++) {
1722 hash = (hash << NAME_HASH_SHIFT) ^
1723 (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
1724 *name++;
1725 }
1726
1727 if (entry->e_value_block == 0 && entry->e_value_size != 0) {
1728 __le32 *value = (__le32 *)((char *)header +
1729 le16_to_cpu(entry->e_value_offs));
1730 for (n = (le32_to_cpu(entry->e_value_size) +
1731 EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) {
1732 hash = (hash << VALUE_HASH_SHIFT) ^
1733 (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
1734 le32_to_cpu(*value++);
1735 }
1736 }
1737 entry->e_hash = cpu_to_le32(hash);
1738}
1739
1740#undef NAME_HASH_SHIFT
1741#undef VALUE_HASH_SHIFT
1742
1743#define BLOCK_HASH_SHIFT 16
1744
1745
1746
1747
1748
1749
1750static void ext4_xattr_rehash(struct ext4_xattr_header *header,
1751 struct ext4_xattr_entry *entry)
1752{
1753 struct ext4_xattr_entry *here;
1754 __u32 hash = 0;
1755
1756 ext4_xattr_hash_entry(header, entry);
1757 here = ENTRY(header+1);
1758 while (!IS_LAST_ENTRY(here)) {
1759 if (!here->e_hash) {
1760
1761 hash = 0;
1762 break;
1763 }
1764 hash = (hash << BLOCK_HASH_SHIFT) ^
1765 (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
1766 le32_to_cpu(here->e_hash);
1767 here = EXT4_XATTR_NEXT(here);
1768 }
1769 header->h_hash = cpu_to_le32(hash);
1770}
1771
1772#undef BLOCK_HASH_SHIFT
1773
1774#define HASH_BUCKET_BITS 10
1775
1776struct mb_cache *
1777ext4_xattr_create_cache(void)
1778{
1779 return mb_cache_create(HASH_BUCKET_BITS);
1780}
1781
1782void ext4_xattr_destroy_cache(struct mb_cache *cache)
1783{
1784 if (cache)
1785 mb_cache_destroy(cache);
1786}
1787
1788
