2 * linux/fs/ext4/xattr.c
4 * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
6 * Fix by Harrison Xing <harrison@mountainviewdata.com>.
7 * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>.
8 * Extended attributes for symlinks and special files added per
9 * suggestion of Luka Renko <luka.renko@hermes.si>.
10 * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
12 * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz
13 * and Andreas Gruenbacher <agruen@suse.de>.
17 * Extended attributes are stored directly in inodes (on file systems with
18 * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
19 * field contains the block number if an inode uses an additional block. All
20 * attributes must fit in the inode and one additional block. Blocks that
21 * contain the identical set of attributes may be shared among several inodes.
22 * Identical blocks are detected by keeping a cache of blocks that have
23 * recently been accessed.
25 * The attributes in inodes and on blocks have a different header; the entries
26 * are stored in the same format:
28 * +------------------+
31 * | entry 2 | | growing downwards
36 * | value 3 | | growing upwards
38 * +------------------+
40 * The header is followed by multiple entry descriptors. In disk blocks, the
41 * entry descriptors are kept sorted. In inodes, they are unsorted. The
42 * attribute values are aligned to the end of the block in no specific order.
46 * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem.
47 * EA blocks are only changed if they are exclusive to an inode, so
48 * holding xattr_sem also means that nothing but the EA block's reference
49 * count can change. Multiple writers to the same block are synchronized
53 #include <linux/init.h>
55 #include <linux/slab.h>
56 #include <linux/mbcache.h>
57 #include <linux/quotaops.h>
58 #include "ext4_jbd2.h"
63 #ifdef EXT4_XATTR_DEBUG
64 # define ea_idebug(inode, fmt, ...) \
65 printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
66 inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
67 # define ea_bdebug(bh, fmt, ...) \
68 printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
69 bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
71 # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
72 # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
75 static void ext4_xattr_cache_insert(struct mb_cache
*, struct buffer_head
*);
76 static struct buffer_head
*ext4_xattr_cache_find(struct inode
*,
77 struct ext4_xattr_header
*,
78 struct mb_cache_entry
**);
79 static void ext4_xattr_rehash(struct ext4_xattr_header
*,
80 struct ext4_xattr_entry
*);
81 static int ext4_xattr_list(struct dentry
*dentry
, char *buffer
,
84 static const struct xattr_handler
*ext4_xattr_handler_map
[] = {
85 [EXT4_XATTR_INDEX_USER
] = &ext4_xattr_user_handler
,
86 #ifdef CONFIG_EXT4_FS_POSIX_ACL
87 [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS
] = &posix_acl_access_xattr_handler
,
88 [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT
] = &posix_acl_default_xattr_handler
,
90 [EXT4_XATTR_INDEX_TRUSTED
] = &ext4_xattr_trusted_handler
,
91 #ifdef CONFIG_EXT4_FS_SECURITY
92 [EXT4_XATTR_INDEX_SECURITY
] = &ext4_xattr_security_handler
,
96 const struct xattr_handler
*ext4_xattr_handlers
[] = {
97 &ext4_xattr_user_handler
,
98 &ext4_xattr_trusted_handler
,
99 #ifdef CONFIG_EXT4_FS_POSIX_ACL
100 &posix_acl_access_xattr_handler
,
101 &posix_acl_default_xattr_handler
,
103 #ifdef CONFIG_EXT4_FS_SECURITY
104 &ext4_xattr_security_handler
,
109 #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \
110 inode->i_sb->s_fs_info)->s_mb_cache)
112 static __le32
ext4_xattr_block_csum(struct inode
*inode
,
114 struct ext4_xattr_header
*hdr
)
116 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
118 __le64 dsk_block_nr
= cpu_to_le64(block_nr
);
119 __u32 dummy_csum
= 0;
120 int offset
= offsetof(struct ext4_xattr_header
, h_checksum
);
122 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&dsk_block_nr
,
123 sizeof(dsk_block_nr
));
124 csum
= ext4_chksum(sbi
, csum
, (__u8
*)hdr
, offset
);
125 csum
= ext4_chksum(sbi
, csum
, (__u8
*)&dummy_csum
, sizeof(dummy_csum
));
126 offset
+= sizeof(dummy_csum
);
127 csum
= ext4_chksum(sbi
, csum
, (__u8
*)hdr
+ offset
,
128 EXT4_BLOCK_SIZE(inode
->i_sb
) - offset
);
130 return cpu_to_le32(csum
);
133 static int ext4_xattr_block_csum_verify(struct inode
*inode
,
134 struct buffer_head
*bh
)
136 struct ext4_xattr_header
*hdr
= BHDR(bh
);
139 if (ext4_has_metadata_csum(inode
->i_sb
)) {
141 ret
= (hdr
->h_checksum
== ext4_xattr_block_csum(inode
,
142 bh
->b_blocknr
, hdr
));
148 static void ext4_xattr_block_csum_set(struct inode
*inode
,
149 struct buffer_head
*bh
)
151 if (ext4_has_metadata_csum(inode
->i_sb
))
152 BHDR(bh
)->h_checksum
= ext4_xattr_block_csum(inode
,
153 bh
->b_blocknr
, BHDR(bh
));
156 static inline const struct xattr_handler
*
157 ext4_xattr_handler(int name_index
)
159 const struct xattr_handler
*handler
= NULL
;
161 if (name_index
> 0 && name_index
< ARRAY_SIZE(ext4_xattr_handler_map
))
162 handler
= ext4_xattr_handler_map
[name_index
];
167 * Inode operation listxattr()
169 * d_inode(dentry)->i_mutex: don't care
172 ext4_listxattr(struct dentry
*dentry
, char *buffer
, size_t size
)
174 return ext4_xattr_list(dentry
, buffer
, size
);
178 ext4_xattr_check_names(struct ext4_xattr_entry
*entry
, void *end
,
181 struct ext4_xattr_entry
*e
= entry
;
183 /* Find the end of the names list */
184 while (!IS_LAST_ENTRY(e
)) {
185 struct ext4_xattr_entry
*next
= EXT4_XATTR_NEXT(e
);
186 if ((void *)next
>= end
)
187 return -EFSCORRUPTED
;
191 /* Check the values */
192 while (!IS_LAST_ENTRY(entry
)) {
193 if (entry
->e_value_block
!= 0)
194 return -EFSCORRUPTED
;
195 if (entry
->e_value_size
!= 0) {
196 u16 offs
= le16_to_cpu(entry
->e_value_offs
);
197 u32 size
= le32_to_cpu(entry
->e_value_size
);
201 * The value cannot overlap the names, and the value
202 * with padding cannot extend beyond 'end'. Check both
203 * the padded and unpadded sizes, since the size may
204 * overflow to 0 when adding padding.
206 if (offs
> end
- value_start
)
207 return -EFSCORRUPTED
;
208 value
= value_start
+ offs
;
209 if (value
< (void *)e
+ sizeof(u32
) ||
210 size
> end
- value
||
211 EXT4_XATTR_SIZE(size
) > end
- value
)
212 return -EFSCORRUPTED
;
214 entry
= EXT4_XATTR_NEXT(entry
);
221 ext4_xattr_check_block(struct inode
*inode
, struct buffer_head
*bh
)
225 if (buffer_verified(bh
))
228 if (BHDR(bh
)->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
) ||
229 BHDR(bh
)->h_blocks
!= cpu_to_le32(1))
230 return -EFSCORRUPTED
;
231 if (!ext4_xattr_block_csum_verify(inode
, bh
))
233 error
= ext4_xattr_check_names(BFIRST(bh
), bh
->b_data
+ bh
->b_size
,
236 set_buffer_verified(bh
);
241 __xattr_check_inode(struct inode
*inode
, struct ext4_xattr_ibody_header
*header
,
242 void *end
, const char *function
, unsigned int line
)
244 int error
= -EFSCORRUPTED
;
246 if (end
- (void *)header
< sizeof(*header
) + sizeof(u32
) ||
247 (header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)))
249 error
= ext4_xattr_check_names(IFIRST(header
), end
, IFIRST(header
));
252 __ext4_error_inode(inode
, function
, line
, 0,
253 "corrupted in-inode xattr");
257 #define xattr_check_inode(inode, header, end) \
258 __xattr_check_inode((inode), (header), (end), __func__, __LINE__)
261 ext4_xattr_check_entry(struct ext4_xattr_entry
*entry
, size_t size
)
263 size_t value_size
= le32_to_cpu(entry
->e_value_size
);
265 if (entry
->e_value_block
!= 0 || value_size
> size
||
266 le16_to_cpu(entry
->e_value_offs
) + value_size
> size
)
267 return -EFSCORRUPTED
;
272 ext4_xattr_find_entry(struct ext4_xattr_entry
**pentry
, int name_index
,
273 const char *name
, size_t size
, int sorted
)
275 struct ext4_xattr_entry
*entry
;
281 name_len
= strlen(name
);
283 for (; !IS_LAST_ENTRY(entry
); entry
= EXT4_XATTR_NEXT(entry
)) {
284 cmp
= name_index
- entry
->e_name_index
;
286 cmp
= name_len
- entry
->e_name_len
;
288 cmp
= memcmp(name
, entry
->e_name
, name_len
);
289 if (cmp
<= 0 && (sorted
|| cmp
== 0))
293 if (!cmp
&& ext4_xattr_check_entry(entry
, size
))
294 return -EFSCORRUPTED
;
295 return cmp
? -ENODATA
: 0;
299 ext4_xattr_block_get(struct inode
*inode
, int name_index
, const char *name
,
300 void *buffer
, size_t buffer_size
)
302 struct buffer_head
*bh
= NULL
;
303 struct ext4_xattr_entry
*entry
;
306 struct mb_cache
*ext4_mb_cache
= EXT4_GET_MB_CACHE(inode
);
308 ea_idebug(inode
, "name=%d.%s, buffer=%p, buffer_size=%ld",
309 name_index
, name
, buffer
, (long)buffer_size
);
312 if (!EXT4_I(inode
)->i_file_acl
)
314 ea_idebug(inode
, "reading block %llu",
315 (unsigned long long)EXT4_I(inode
)->i_file_acl
);
316 bh
= sb_bread(inode
->i_sb
, EXT4_I(inode
)->i_file_acl
);
319 ea_bdebug(bh
, "b_count=%d, refcount=%d",
320 atomic_read(&(bh
->b_count
)), le32_to_cpu(BHDR(bh
)->h_refcount
));
321 if (ext4_xattr_check_block(inode
, bh
)) {
323 EXT4_ERROR_INODE(inode
, "bad block %llu",
324 EXT4_I(inode
)->i_file_acl
);
325 error
= -EFSCORRUPTED
;
328 ext4_xattr_cache_insert(ext4_mb_cache
, bh
);
330 error
= ext4_xattr_find_entry(&entry
, name_index
, name
, bh
->b_size
, 1);
331 if (error
== -EFSCORRUPTED
)
335 size
= le32_to_cpu(entry
->e_value_size
);
338 if (size
> buffer_size
)
340 memcpy(buffer
, bh
->b_data
+ le16_to_cpu(entry
->e_value_offs
),
351 ext4_xattr_ibody_get(struct inode
*inode
, int name_index
, const char *name
,
352 void *buffer
, size_t buffer_size
)
354 struct ext4_xattr_ibody_header
*header
;
355 struct ext4_xattr_entry
*entry
;
356 struct ext4_inode
*raw_inode
;
357 struct ext4_iloc iloc
;
362 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
))
364 error
= ext4_get_inode_loc(inode
, &iloc
);
367 raw_inode
= ext4_raw_inode(&iloc
);
368 header
= IHDR(inode
, raw_inode
);
369 entry
= IFIRST(header
);
370 end
= (void *)raw_inode
+ EXT4_SB(inode
->i_sb
)->s_inode_size
;
371 error
= xattr_check_inode(inode
, header
, end
);
374 error
= ext4_xattr_find_entry(&entry
, name_index
, name
,
375 end
- (void *)entry
, 0);
378 size
= le32_to_cpu(entry
->e_value_size
);
381 if (size
> buffer_size
)
383 memcpy(buffer
, (void *)IFIRST(header
) +
384 le16_to_cpu(entry
->e_value_offs
), size
);
396 * Copy an extended attribute into the buffer
397 * provided, or compute the buffer size required.
398 * Buffer is NULL to compute the size of the buffer required.
400 * Returns a negative error number on failure, or the number of bytes
401 * used / required on success.
404 ext4_xattr_get(struct inode
*inode
, int name_index
, const char *name
,
405 void *buffer
, size_t buffer_size
)
409 if (strlen(name
) > 255)
412 down_read(&EXT4_I(inode
)->xattr_sem
);
413 error
= ext4_xattr_ibody_get(inode
, name_index
, name
, buffer
,
415 if (error
== -ENODATA
)
416 error
= ext4_xattr_block_get(inode
, name_index
, name
, buffer
,
418 up_read(&EXT4_I(inode
)->xattr_sem
);
423 ext4_xattr_list_entries(struct dentry
*dentry
, struct ext4_xattr_entry
*entry
,
424 char *buffer
, size_t buffer_size
)
426 size_t rest
= buffer_size
;
428 for (; !IS_LAST_ENTRY(entry
); entry
= EXT4_XATTR_NEXT(entry
)) {
429 const struct xattr_handler
*handler
=
430 ext4_xattr_handler(entry
->e_name_index
);
432 if (handler
&& (!handler
->list
|| handler
->list(dentry
))) {
433 const char *prefix
= handler
->prefix
?: handler
->name
;
434 size_t prefix_len
= strlen(prefix
);
435 size_t size
= prefix_len
+ entry
->e_name_len
+ 1;
440 memcpy(buffer
, prefix
, prefix_len
);
441 buffer
+= prefix_len
;
442 memcpy(buffer
, entry
->e_name
, entry
->e_name_len
);
443 buffer
+= entry
->e_name_len
;
449 return buffer_size
- rest
; /* total size */
453 ext4_xattr_block_list(struct dentry
*dentry
, char *buffer
, size_t buffer_size
)
455 struct inode
*inode
= d_inode(dentry
);
456 struct buffer_head
*bh
= NULL
;
458 struct mb_cache
*ext4_mb_cache
= EXT4_GET_MB_CACHE(inode
);
460 ea_idebug(inode
, "buffer=%p, buffer_size=%ld",
461 buffer
, (long)buffer_size
);
464 if (!EXT4_I(inode
)->i_file_acl
)
466 ea_idebug(inode
, "reading block %llu",
467 (unsigned long long)EXT4_I(inode
)->i_file_acl
);
468 bh
= sb_bread(inode
->i_sb
, EXT4_I(inode
)->i_file_acl
);
472 ea_bdebug(bh
, "b_count=%d, refcount=%d",
473 atomic_read(&(bh
->b_count
)), le32_to_cpu(BHDR(bh
)->h_refcount
));
474 if (ext4_xattr_check_block(inode
, bh
)) {
475 EXT4_ERROR_INODE(inode
, "bad block %llu",
476 EXT4_I(inode
)->i_file_acl
);
477 error
= -EFSCORRUPTED
;
480 ext4_xattr_cache_insert(ext4_mb_cache
, bh
);
481 error
= ext4_xattr_list_entries(dentry
, BFIRST(bh
), buffer
, buffer_size
);
490 ext4_xattr_ibody_list(struct dentry
*dentry
, char *buffer
, size_t buffer_size
)
492 struct inode
*inode
= d_inode(dentry
);
493 struct ext4_xattr_ibody_header
*header
;
494 struct ext4_inode
*raw_inode
;
495 struct ext4_iloc iloc
;
499 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
))
501 error
= ext4_get_inode_loc(inode
, &iloc
);
504 raw_inode
= ext4_raw_inode(&iloc
);
505 header
= IHDR(inode
, raw_inode
);
506 end
= (void *)raw_inode
+ EXT4_SB(inode
->i_sb
)->s_inode_size
;
507 error
= xattr_check_inode(inode
, header
, end
);
510 error
= ext4_xattr_list_entries(dentry
, IFIRST(header
),
511 buffer
, buffer_size
);
521 * Copy a list of attribute names into the buffer
522 * provided, or compute the buffer size required.
523 * Buffer is NULL to compute the size of the buffer required.
525 * Returns a negative error number on failure, or the number of bytes
526 * used / required on success.
529 ext4_xattr_list(struct dentry
*dentry
, char *buffer
, size_t buffer_size
)
533 down_read(&EXT4_I(d_inode(dentry
))->xattr_sem
);
534 ret
= ret2
= ext4_xattr_ibody_list(dentry
, buffer
, buffer_size
);
541 ret
= ext4_xattr_block_list(dentry
, buffer
, buffer_size
);
546 up_read(&EXT4_I(d_inode(dentry
))->xattr_sem
);
551 * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is
554 static void ext4_xattr_update_super_block(handle_t
*handle
,
555 struct super_block
*sb
)
557 if (ext4_has_feature_xattr(sb
))
560 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get_write_access");
561 if (ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
) == 0) {
562 ext4_set_feature_xattr(sb
);
563 ext4_handle_dirty_super(handle
, sb
);
568 * Release the xattr block BH: If the reference count is > 1, decrement it;
569 * otherwise free the block.
572 ext4_xattr_release_block(handle_t
*handle
, struct inode
*inode
,
573 struct buffer_head
*bh
)
575 struct mb_cache
*ext4_mb_cache
= EXT4_GET_MB_CACHE(inode
);
579 BUFFER_TRACE(bh
, "get_write_access");
580 error
= ext4_journal_get_write_access(handle
, bh
);
585 hash
= le32_to_cpu(BHDR(bh
)->h_hash
);
586 ref
= le32_to_cpu(BHDR(bh
)->h_refcount
);
588 ea_bdebug(bh
, "refcount now=0; freeing");
590 * This must happen under buffer lock for
591 * ext4_xattr_block_set() to reliably detect freed block
593 mb_cache_entry_delete_block(ext4_mb_cache
, hash
, bh
->b_blocknr
);
596 ext4_free_blocks(handle
, inode
, bh
, 0, 1,
597 EXT4_FREE_BLOCKS_METADATA
|
598 EXT4_FREE_BLOCKS_FORGET
);
601 BHDR(bh
)->h_refcount
= cpu_to_le32(ref
);
602 if (ref
== EXT4_XATTR_REFCOUNT_MAX
- 1) {
603 struct mb_cache_entry
*ce
;
605 ce
= mb_cache_entry_get(ext4_mb_cache
, hash
,
609 mb_cache_entry_put(ext4_mb_cache
, ce
);
613 ext4_xattr_block_csum_set(inode
, bh
);
615 * Beware of this ugliness: Releasing of xattr block references
616 * from different inodes can race and so we have to protect
617 * from a race where someone else frees the block (and releases
618 * its journal_head) before we are done dirtying the buffer. In
619 * nojournal mode this race is harmless and we actually cannot
620 * call ext4_handle_dirty_metadata() with locked buffer as
621 * that function can call sync_dirty_buffer() so for that case
622 * we handle the dirtying after unlocking the buffer.
624 if (ext4_handle_valid(handle
))
625 error
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
627 if (!ext4_handle_valid(handle
))
628 error
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
630 ext4_handle_sync(handle
);
631 dquot_free_block(inode
, EXT4_C2B(EXT4_SB(inode
->i_sb
), 1));
632 ea_bdebug(bh
, "refcount now=%d; releasing",
633 le32_to_cpu(BHDR(bh
)->h_refcount
));
636 ext4_std_error(inode
->i_sb
, error
);
641 * Find the available free space for EAs. This also returns the total number of
642 * bytes used by EA entries.
644 static size_t ext4_xattr_free_space(struct ext4_xattr_entry
*last
,
645 size_t *min_offs
, void *base
, int *total
)
647 for (; !IS_LAST_ENTRY(last
); last
= EXT4_XATTR_NEXT(last
)) {
648 if (last
->e_value_size
) {
649 size_t offs
= le16_to_cpu(last
->e_value_offs
);
650 if (offs
< *min_offs
)
654 *total
+= EXT4_XATTR_LEN(last
->e_name_len
);
656 return (*min_offs
- ((void *)last
- base
) - sizeof(__u32
));
660 ext4_xattr_set_entry(struct ext4_xattr_info
*i
, struct ext4_xattr_search
*s
)
662 struct ext4_xattr_entry
*last
;
663 size_t free
, min_offs
= s
->end
- s
->base
, name_len
= strlen(i
->name
);
665 /* Compute min_offs and last. */
667 for (; !IS_LAST_ENTRY(last
); last
= EXT4_XATTR_NEXT(last
)) {
668 if (last
->e_value_size
) {
669 size_t offs
= le16_to_cpu(last
->e_value_offs
);
674 free
= min_offs
- ((void *)last
- s
->base
) - sizeof(__u32
);
676 if (s
->here
->e_value_size
) {
677 size_t size
= le32_to_cpu(s
->here
->e_value_size
);
678 free
+= EXT4_XATTR_SIZE(size
);
680 free
+= EXT4_XATTR_LEN(name_len
);
683 if (free
< EXT4_XATTR_LEN(name_len
) +
684 EXT4_XATTR_SIZE(i
->value_len
))
688 if (i
->value
&& s
->not_found
) {
689 /* Insert the new name. */
690 size_t size
= EXT4_XATTR_LEN(name_len
);
691 size_t rest
= (void *)last
- (void *)s
->here
+ sizeof(__u32
);
692 memmove((void *)s
->here
+ size
, s
->here
, rest
);
693 memset(s
->here
, 0, size
);
694 s
->here
->e_name_index
= i
->name_index
;
695 s
->here
->e_name_len
= name_len
;
696 memcpy(s
->here
->e_name
, i
->name
, name_len
);
698 if (s
->here
->e_value_size
) {
699 void *first_val
= s
->base
+ min_offs
;
700 size_t offs
= le16_to_cpu(s
->here
->e_value_offs
);
701 void *val
= s
->base
+ offs
;
702 size_t size
= EXT4_XATTR_SIZE(
703 le32_to_cpu(s
->here
->e_value_size
));
705 if (i
->value
&& size
== EXT4_XATTR_SIZE(i
->value_len
)) {
706 /* The old and the new value have the same
707 size. Just replace. */
708 s
->here
->e_value_size
=
709 cpu_to_le32(i
->value_len
);
710 if (i
->value
== EXT4_ZERO_XATTR_VALUE
) {
711 memset(val
, 0, size
);
713 /* Clear pad bytes first. */
714 memset(val
+ size
- EXT4_XATTR_PAD
, 0,
716 memcpy(val
, i
->value
, i
->value_len
);
721 /* Remove the old value. */
722 memmove(first_val
+ size
, first_val
, val
- first_val
);
723 memset(first_val
, 0, size
);
724 s
->here
->e_value_size
= 0;
725 s
->here
->e_value_offs
= 0;
728 /* Adjust all value offsets. */
730 while (!IS_LAST_ENTRY(last
)) {
731 size_t o
= le16_to_cpu(last
->e_value_offs
);
732 if (last
->e_value_size
&& o
< offs
)
734 cpu_to_le16(o
+ size
);
735 last
= EXT4_XATTR_NEXT(last
);
739 /* Remove the old name. */
740 size_t size
= EXT4_XATTR_LEN(name_len
);
741 last
= ENTRY((void *)last
- size
);
742 memmove(s
->here
, (void *)s
->here
+ size
,
743 (void *)last
- (void *)s
->here
+ sizeof(__u32
));
744 memset(last
, 0, size
);
749 /* Insert the new value. */
750 s
->here
->e_value_size
= cpu_to_le32(i
->value_len
);
752 size_t size
= EXT4_XATTR_SIZE(i
->value_len
);
753 void *val
= s
->base
+ min_offs
- size
;
754 s
->here
->e_value_offs
= cpu_to_le16(min_offs
- size
);
755 if (i
->value
== EXT4_ZERO_XATTR_VALUE
) {
756 memset(val
, 0, size
);
758 /* Clear the pad bytes first. */
759 memset(val
+ size
- EXT4_XATTR_PAD
, 0,
761 memcpy(val
, i
->value
, i
->value_len
);
768 struct ext4_xattr_block_find
{
769 struct ext4_xattr_search s
;
770 struct buffer_head
*bh
;
774 ext4_xattr_block_find(struct inode
*inode
, struct ext4_xattr_info
*i
,
775 struct ext4_xattr_block_find
*bs
)
777 struct super_block
*sb
= inode
->i_sb
;
780 ea_idebug(inode
, "name=%d.%s, value=%p, value_len=%ld",
781 i
->name_index
, i
->name
, i
->value
, (long)i
->value_len
);
783 if (EXT4_I(inode
)->i_file_acl
) {
784 /* The inode already has an extended attribute block. */
785 bs
->bh
= sb_bread(sb
, EXT4_I(inode
)->i_file_acl
);
789 ea_bdebug(bs
->bh
, "b_count=%d, refcount=%d",
790 atomic_read(&(bs
->bh
->b_count
)),
791 le32_to_cpu(BHDR(bs
->bh
)->h_refcount
));
792 if (ext4_xattr_check_block(inode
, bs
->bh
)) {
793 EXT4_ERROR_INODE(inode
, "bad block %llu",
794 EXT4_I(inode
)->i_file_acl
);
795 error
= -EFSCORRUPTED
;
798 /* Find the named attribute. */
799 bs
->s
.base
= BHDR(bs
->bh
);
800 bs
->s
.first
= BFIRST(bs
->bh
);
801 bs
->s
.end
= bs
->bh
->b_data
+ bs
->bh
->b_size
;
802 bs
->s
.here
= bs
->s
.first
;
803 error
= ext4_xattr_find_entry(&bs
->s
.here
, i
->name_index
,
804 i
->name
, bs
->bh
->b_size
, 1);
805 if (error
&& error
!= -ENODATA
)
807 bs
->s
.not_found
= error
;
816 ext4_xattr_block_set(handle_t
*handle
, struct inode
*inode
,
817 struct ext4_xattr_info
*i
,
818 struct ext4_xattr_block_find
*bs
)
820 struct super_block
*sb
= inode
->i_sb
;
821 struct buffer_head
*new_bh
= NULL
;
822 struct ext4_xattr_search
*s
= &bs
->s
;
823 struct mb_cache_entry
*ce
= NULL
;
825 struct mb_cache
*ext4_mb_cache
= EXT4_GET_MB_CACHE(inode
);
827 #define header(x) ((struct ext4_xattr_header *)(x))
829 if (i
->value
&& i
->value_len
> sb
->s_blocksize
)
832 BUFFER_TRACE(bs
->bh
, "get_write_access");
833 error
= ext4_journal_get_write_access(handle
, bs
->bh
);
838 if (header(s
->base
)->h_refcount
== cpu_to_le32(1)) {
839 __u32 hash
= le32_to_cpu(BHDR(bs
->bh
)->h_hash
);
842 * This must happen under buffer lock for
843 * ext4_xattr_block_set() to reliably detect modified
846 mb_cache_entry_delete_block(ext4_mb_cache
, hash
,
848 ea_bdebug(bs
->bh
, "modifying in-place");
849 error
= ext4_xattr_set_entry(i
, s
);
851 if (!IS_LAST_ENTRY(s
->first
))
852 ext4_xattr_rehash(header(s
->base
),
854 ext4_xattr_cache_insert(ext4_mb_cache
,
857 ext4_xattr_block_csum_set(inode
, bs
->bh
);
858 unlock_buffer(bs
->bh
);
859 if (error
== -EFSCORRUPTED
)
862 error
= ext4_handle_dirty_metadata(handle
,
869 int offset
= (char *)s
->here
- bs
->bh
->b_data
;
871 unlock_buffer(bs
->bh
);
872 ea_bdebug(bs
->bh
, "cloning");
873 s
->base
= kmalloc(bs
->bh
->b_size
, GFP_NOFS
);
877 memcpy(s
->base
, BHDR(bs
->bh
), bs
->bh
->b_size
);
878 s
->first
= ENTRY(header(s
->base
)+1);
879 header(s
->base
)->h_refcount
= cpu_to_le32(1);
880 s
->here
= ENTRY(s
->base
+ offset
);
881 s
->end
= s
->base
+ bs
->bh
->b_size
;
884 /* Allocate a buffer where we construct the new block. */
885 s
->base
= kzalloc(sb
->s_blocksize
, GFP_NOFS
);
886 /* assert(header == s->base) */
890 header(s
->base
)->h_magic
= cpu_to_le32(EXT4_XATTR_MAGIC
);
891 header(s
->base
)->h_blocks
= cpu_to_le32(1);
892 header(s
->base
)->h_refcount
= cpu_to_le32(1);
893 s
->first
= ENTRY(header(s
->base
)+1);
894 s
->here
= ENTRY(header(s
->base
)+1);
895 s
->end
= s
->base
+ sb
->s_blocksize
;
898 error
= ext4_xattr_set_entry(i
, s
);
899 if (error
== -EFSCORRUPTED
)
903 if (!IS_LAST_ENTRY(s
->first
))
904 ext4_xattr_rehash(header(s
->base
), s
->here
);
907 if (!IS_LAST_ENTRY(s
->first
)) {
908 new_bh
= ext4_xattr_cache_find(inode
, header(s
->base
), &ce
);
910 /* We found an identical block in the cache. */
911 if (new_bh
== bs
->bh
)
912 ea_bdebug(new_bh
, "keeping");
916 /* The old block is released after updating
918 error
= dquot_alloc_block(inode
,
919 EXT4_C2B(EXT4_SB(sb
), 1));
922 BUFFER_TRACE(new_bh
, "get_write_access");
923 error
= ext4_journal_get_write_access(handle
,
929 * We have to be careful about races with
930 * freeing, rehashing or adding references to
931 * xattr block. Once we hold buffer lock xattr
932 * block's state is stable so we can check
933 * whether the block got freed / rehashed or
934 * not. Since we unhash mbcache entry under
935 * buffer lock when freeing / rehashing xattr
936 * block, checking whether entry is still
937 * hashed is reliable. Same rules hold for
938 * e_reusable handling.
940 if (hlist_bl_unhashed(&ce
->e_hash_list
) ||
943 * Undo everything and check mbcache
946 unlock_buffer(new_bh
);
947 dquot_free_block(inode
,
948 EXT4_C2B(EXT4_SB(sb
),
951 mb_cache_entry_put(ext4_mb_cache
, ce
);
956 ref
= le32_to_cpu(BHDR(new_bh
)->h_refcount
) + 1;
957 BHDR(new_bh
)->h_refcount
= cpu_to_le32(ref
);
958 if (ref
>= EXT4_XATTR_REFCOUNT_MAX
)
960 ea_bdebug(new_bh
, "reusing; refcount now=%d",
962 ext4_xattr_block_csum_set(inode
, new_bh
);
963 unlock_buffer(new_bh
);
964 error
= ext4_handle_dirty_metadata(handle
,
970 mb_cache_entry_touch(ext4_mb_cache
, ce
);
971 mb_cache_entry_put(ext4_mb_cache
, ce
);
973 } else if (bs
->bh
&& s
->base
== bs
->bh
->b_data
) {
974 /* We were modifying this block in-place. */
975 ea_bdebug(bs
->bh
, "keeping this block");
979 /* We need to allocate a new block */
980 ext4_fsblk_t goal
, block
;
982 goal
= ext4_group_first_block_no(sb
,
983 EXT4_I(inode
)->i_block_group
);
985 /* non-extent files can't have physical blocks past 2^32 */
986 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
987 goal
= goal
& EXT4_MAX_BLOCK_FILE_PHYS
;
989 block
= ext4_new_meta_blocks(handle
, inode
, goal
, 0,
994 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
995 BUG_ON(block
> EXT4_MAX_BLOCK_FILE_PHYS
);
997 ea_idebug(inode
, "creating block %llu",
998 (unsigned long long)block
);
1000 new_bh
= sb_getblk(sb
, block
);
1001 if (unlikely(!new_bh
)) {
1004 ext4_free_blocks(handle
, inode
, NULL
, block
, 1,
1005 EXT4_FREE_BLOCKS_METADATA
);
1008 lock_buffer(new_bh
);
1009 error
= ext4_journal_get_create_access(handle
, new_bh
);
1011 unlock_buffer(new_bh
);
1015 memcpy(new_bh
->b_data
, s
->base
, new_bh
->b_size
);
1016 ext4_xattr_block_csum_set(inode
, new_bh
);
1017 set_buffer_uptodate(new_bh
);
1018 unlock_buffer(new_bh
);
1019 ext4_xattr_cache_insert(ext4_mb_cache
, new_bh
);
1020 error
= ext4_handle_dirty_metadata(handle
, inode
,
1027 /* Update the inode. */
1028 EXT4_I(inode
)->i_file_acl
= new_bh
? new_bh
->b_blocknr
: 0;
1030 /* Drop the previous xattr block. */
1031 if (bs
->bh
&& bs
->bh
!= new_bh
)
1032 ext4_xattr_release_block(handle
, inode
, bs
->bh
);
1037 mb_cache_entry_put(ext4_mb_cache
, ce
);
1039 if (!(bs
->bh
&& s
->base
== bs
->bh
->b_data
))
1045 dquot_free_block(inode
, EXT4_C2B(EXT4_SB(sb
), 1));
1049 EXT4_ERROR_INODE(inode
, "bad block %llu",
1050 EXT4_I(inode
)->i_file_acl
);
1056 int ext4_xattr_ibody_find(struct inode
*inode
, struct ext4_xattr_info
*i
,
1057 struct ext4_xattr_ibody_find
*is
)
1059 struct ext4_xattr_ibody_header
*header
;
1060 struct ext4_inode
*raw_inode
;
1063 if (EXT4_I(inode
)->i_extra_isize
== 0)
1065 raw_inode
= ext4_raw_inode(&is
->iloc
);
1066 header
= IHDR(inode
, raw_inode
);
1067 is
->s
.base
= is
->s
.first
= IFIRST(header
);
1068 is
->s
.here
= is
->s
.first
;
1069 is
->s
.end
= (void *)raw_inode
+ EXT4_SB(inode
->i_sb
)->s_inode_size
;
1070 if (ext4_test_inode_state(inode
, EXT4_STATE_XATTR
)) {
1071 error
= xattr_check_inode(inode
, header
, is
->s
.end
);
1074 /* Find the named attribute. */
1075 error
= ext4_xattr_find_entry(&is
->s
.here
, i
->name_index
,
1076 i
->name
, is
->s
.end
-
1077 (void *)is
->s
.base
, 0);
1078 if (error
&& error
!= -ENODATA
)
1080 is
->s
.not_found
= error
;
1085 int ext4_xattr_ibody_inline_set(handle_t
*handle
, struct inode
*inode
,
1086 struct ext4_xattr_info
*i
,
1087 struct ext4_xattr_ibody_find
*is
)
1089 struct ext4_xattr_ibody_header
*header
;
1090 struct ext4_xattr_search
*s
= &is
->s
;
1093 if (EXT4_I(inode
)->i_extra_isize
== 0)
1095 error
= ext4_xattr_set_entry(i
, s
);
1097 if (error
== -ENOSPC
&&
1098 ext4_has_inline_data(inode
)) {
1099 error
= ext4_try_to_evict_inline_data(handle
, inode
,
1100 EXT4_XATTR_LEN(strlen(i
->name
) +
1101 EXT4_XATTR_SIZE(i
->value_len
)));
1104 error
= ext4_xattr_ibody_find(inode
, i
, is
);
1107 error
= ext4_xattr_set_entry(i
, s
);
1112 header
= IHDR(inode
, ext4_raw_inode(&is
->iloc
));
1113 if (!IS_LAST_ENTRY(s
->first
)) {
1114 header
->h_magic
= cpu_to_le32(EXT4_XATTR_MAGIC
);
1115 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
1117 header
->h_magic
= cpu_to_le32(0);
1118 ext4_clear_inode_state(inode
, EXT4_STATE_XATTR
);
1123 static int ext4_xattr_ibody_set(struct inode
*inode
,
1124 struct ext4_xattr_info
*i
,
1125 struct ext4_xattr_ibody_find
*is
)
1127 struct ext4_xattr_ibody_header
*header
;
1128 struct ext4_xattr_search
*s
= &is
->s
;
1131 if (EXT4_I(inode
)->i_extra_isize
== 0)
1133 error
= ext4_xattr_set_entry(i
, s
);
1136 header
= IHDR(inode
, ext4_raw_inode(&is
->iloc
));
1137 if (!IS_LAST_ENTRY(s
->first
)) {
1138 header
->h_magic
= cpu_to_le32(EXT4_XATTR_MAGIC
);
1139 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
1141 header
->h_magic
= cpu_to_le32(0);
1142 ext4_clear_inode_state(inode
, EXT4_STATE_XATTR
);
1147 static int ext4_xattr_value_same(struct ext4_xattr_search
*s
,
1148 struct ext4_xattr_info
*i
)
1152 if (le32_to_cpu(s
->here
->e_value_size
) != i
->value_len
)
1154 value
= ((void *)s
->base
) + le16_to_cpu(s
->here
->e_value_offs
);
1155 return !memcmp(value
, i
->value
, i
->value_len
);
1159 * ext4_xattr_set_handle()
1161 * Create, replace or remove an extended attribute for this inode. Value
1162 * is NULL to remove an existing extended attribute, and non-NULL to
1163 * either replace an existing extended attribute, or create a new extended
1164 * attribute. The flags XATTR_REPLACE and XATTR_CREATE
1165 * specify that an extended attribute must exist and must not exist
1166 * previous to the call, respectively.
1168 * Returns 0, or a negative error number on failure.
1171 ext4_xattr_set_handle(handle_t
*handle
, struct inode
*inode
, int name_index
,
1172 const char *name
, const void *value
, size_t value_len
,
1175 struct ext4_xattr_info i
= {
1176 .name_index
= name_index
,
1179 .value_len
= value_len
,
1182 struct ext4_xattr_ibody_find is
= {
1183 .s
= { .not_found
= -ENODATA
, },
1185 struct ext4_xattr_block_find bs
= {
1186 .s
= { .not_found
= -ENODATA
, },
1193 if (strlen(name
) > 255)
1195 ext4_write_lock_xattr(inode
, &no_expand
);
1197 error
= ext4_reserve_inode_write(handle
, inode
, &is
.iloc
);
1201 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
)) {
1202 struct ext4_inode
*raw_inode
= ext4_raw_inode(&is
.iloc
);
1203 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
1204 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
1207 error
= ext4_xattr_ibody_find(inode
, &i
, &is
);
1211 error
= ext4_xattr_block_find(inode
, &i
, &bs
);
1214 if (is
.s
.not_found
&& bs
.s
.not_found
) {
1216 if (flags
& XATTR_REPLACE
)
1223 if (flags
& XATTR_CREATE
)
1227 if (!is
.s
.not_found
)
1228 error
= ext4_xattr_ibody_set(inode
, &i
, &is
);
1229 else if (!bs
.s
.not_found
)
1230 error
= ext4_xattr_block_set(handle
, inode
, &i
, &bs
);
1233 /* Xattr value did not change? Save us some work and bail out */
1234 if (!is
.s
.not_found
&& ext4_xattr_value_same(&is
.s
, &i
))
1236 if (!bs
.s
.not_found
&& ext4_xattr_value_same(&bs
.s
, &i
))
1239 error
= ext4_xattr_ibody_set(inode
, &i
, &is
);
1240 if (!error
&& !bs
.s
.not_found
) {
1242 error
= ext4_xattr_block_set(handle
, inode
, &i
, &bs
);
1243 } else if (error
== -ENOSPC
) {
1244 if (EXT4_I(inode
)->i_file_acl
&& !bs
.s
.base
) {
1245 error
= ext4_xattr_block_find(inode
, &i
, &bs
);
1249 error
= ext4_xattr_block_set(handle
, inode
, &i
, &bs
);
1252 if (!is
.s
.not_found
) {
1254 error
= ext4_xattr_ibody_set(inode
, &i
, &is
);
1259 ext4_xattr_update_super_block(handle
, inode
->i_sb
);
1260 inode
->i_ctime
= current_time(inode
);
1263 error
= ext4_mark_iloc_dirty(handle
, inode
, &is
.iloc
);
1265 * The bh is consumed by ext4_mark_iloc_dirty, even with
1270 ext4_handle_sync(handle
);
1276 ext4_write_unlock_xattr(inode
, &no_expand
);
1283 * Like ext4_xattr_set_handle, but start from an inode. This extended
1284 * attribute modification is a filesystem transaction by itself.
1286 * Returns 0, or a negative error number on failure.
1289 ext4_xattr_set(struct inode
*inode
, int name_index
, const char *name
,
1290 const void *value
, size_t value_len
, int flags
)
1293 int error
, retries
= 0;
1294 int credits
= ext4_jbd2_credits_xattr(inode
);
1297 handle
= ext4_journal_start(inode
, EXT4_HT_XATTR
, credits
);
1298 if (IS_ERR(handle
)) {
1299 error
= PTR_ERR(handle
);
1303 error
= ext4_xattr_set_handle(handle
, inode
, name_index
, name
,
1304 value
, value_len
, flags
);
1305 error2
= ext4_journal_stop(handle
);
1306 if (error
== -ENOSPC
&&
1307 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
1317 * Shift the EA entries in the inode to create space for the increased
1320 static void ext4_xattr_shift_entries(struct ext4_xattr_entry
*entry
,
1321 int value_offs_shift
, void *to
,
1322 void *from
, size_t n
)
1324 struct ext4_xattr_entry
*last
= entry
;
1327 /* We always shift xattr headers further thus offsets get lower */
1328 BUG_ON(value_offs_shift
> 0);
1330 /* Adjust the value offsets of the entries */
1331 for (; !IS_LAST_ENTRY(last
); last
= EXT4_XATTR_NEXT(last
)) {
1332 if (last
->e_value_size
) {
1333 new_offs
= le16_to_cpu(last
->e_value_offs
) +
1335 last
->e_value_offs
= cpu_to_le16(new_offs
);
1338 /* Shift the entries by n bytes */
1339 memmove(to
, from
, n
);
1343 * Move xattr pointed to by 'entry' from inode into external xattr block
1345 static int ext4_xattr_move_to_block(handle_t
*handle
, struct inode
*inode
,
1346 struct ext4_inode
*raw_inode
,
1347 struct ext4_xattr_entry
*entry
)
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 value_offs
, value_size
;
1353 struct ext4_xattr_info i
= {
1356 .name_index
= entry
->e_name_index
,
1358 struct ext4_xattr_ibody_header
*header
= IHDR(inode
, raw_inode
);
1361 value_offs
= le16_to_cpu(entry
->e_value_offs
);
1362 value_size
= le32_to_cpu(entry
->e_value_size
);
1364 is
= kzalloc(sizeof(struct ext4_xattr_ibody_find
), GFP_NOFS
);
1365 bs
= kzalloc(sizeof(struct ext4_xattr_block_find
), GFP_NOFS
);
1366 buffer
= kmalloc(value_size
, GFP_NOFS
);
1367 b_entry_name
= kmalloc(entry
->e_name_len
+ 1, GFP_NOFS
);
1368 if (!is
|| !bs
|| !buffer
|| !b_entry_name
) {
1373 is
->s
.not_found
= -ENODATA
;
1374 bs
->s
.not_found
= -ENODATA
;
1378 /* Save the entry name and the entry value */
1379 memcpy(buffer
, (void *)IFIRST(header
) + value_offs
, value_size
);
1380 memcpy(b_entry_name
, entry
->e_name
, entry
->e_name_len
);
1381 b_entry_name
[entry
->e_name_len
] = '\0';
1382 i
.name
= b_entry_name
;
1384 error
= ext4_get_inode_loc(inode
, &is
->iloc
);
1388 error
= ext4_xattr_ibody_find(inode
, &i
, is
);
1392 /* Remove the chosen entry from the inode */
1393 error
= ext4_xattr_ibody_set(inode
, &i
, is
);
1397 i
.name
= b_entry_name
;
1399 i
.value_len
= value_size
;
1400 error
= ext4_xattr_block_find(inode
, &i
, bs
);
1404 /* Add entry which was removed from the inode into the block */
1405 error
= ext4_xattr_block_set(handle
, inode
, &i
, bs
);
1410 kfree(b_entry_name
);
1413 brelse(is
->iloc
.bh
);
1420 static int ext4_xattr_make_inode_space(handle_t
*handle
, struct inode
*inode
,
1421 struct ext4_inode
*raw_inode
,
1422 int isize_diff
, size_t ifree
,
1423 size_t bfree
, int *total_ino
)
1425 struct ext4_xattr_ibody_header
*header
= IHDR(inode
, raw_inode
);
1426 struct ext4_xattr_entry
*small_entry
;
1427 struct ext4_xattr_entry
*entry
;
1428 struct ext4_xattr_entry
*last
;
1429 unsigned int entry_size
; /* EA entry size */
1430 unsigned int total_size
; /* EA entry size + value size */
1431 unsigned int min_total_size
;
1434 while (isize_diff
> ifree
) {
1437 min_total_size
= ~0U;
1438 last
= IFIRST(header
);
1439 /* Find the entry best suited to be pushed into EA block */
1440 for (; !IS_LAST_ENTRY(last
); last
= EXT4_XATTR_NEXT(last
)) {
1442 EXT4_XATTR_SIZE(le32_to_cpu(last
->e_value_size
)) +
1443 EXT4_XATTR_LEN(last
->e_name_len
);
1444 if (total_size
<= bfree
&&
1445 total_size
< min_total_size
) {
1446 if (total_size
+ ifree
< isize_diff
) {
1450 min_total_size
= total_size
;
1455 if (entry
== NULL
) {
1456 if (small_entry
== NULL
)
1458 entry
= small_entry
;
1461 entry_size
= EXT4_XATTR_LEN(entry
->e_name_len
);
1462 total_size
= entry_size
+
1463 EXT4_XATTR_SIZE(le32_to_cpu(entry
->e_value_size
));
1464 error
= ext4_xattr_move_to_block(handle
, inode
, raw_inode
,
1469 *total_ino
-= entry_size
;
1470 ifree
+= total_size
;
1471 bfree
-= total_size
;
1478 * Expand an inode by new_extra_isize bytes when EAs are present.
1479 * Returns 0 on success or negative error number on failure.
1481 int ext4_expand_extra_isize_ea(struct inode
*inode
, int new_extra_isize
,
1482 struct ext4_inode
*raw_inode
, handle_t
*handle
)
1484 struct ext4_xattr_ibody_header
*header
;
1485 struct buffer_head
*bh
= NULL
;
1487 size_t ifree
, bfree
;
1490 int error
= 0, tried_min_extra_isize
= 0;
1491 int s_min_extra_isize
= le16_to_cpu(EXT4_SB(inode
->i_sb
)->s_es
->s_min_extra_isize
);
1492 int isize_diff
; /* How much do we need to grow i_extra_isize */
1495 if (ext4_write_trylock_xattr(inode
, &no_expand
) == 0)
1499 isize_diff
= new_extra_isize
- EXT4_I(inode
)->i_extra_isize
;
1500 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
1503 header
= IHDR(inode
, raw_inode
);
1506 * Check if enough free space is available in the inode to shift the
1507 * entries ahead by new_extra_isize.
1510 base
= IFIRST(header
);
1511 end
= (void *)raw_inode
+ EXT4_SB(inode
->i_sb
)->s_inode_size
;
1512 min_offs
= end
- base
;
1513 total_ino
= sizeof(struct ext4_xattr_ibody_header
);
1515 error
= xattr_check_inode(inode
, header
, end
);
1519 ifree
= ext4_xattr_free_space(base
, &min_offs
, base
, &total_ino
);
1520 if (ifree
>= isize_diff
)
1524 * Enough free space isn't available in the inode, check if
1525 * EA block can hold new_extra_isize bytes.
1527 if (EXT4_I(inode
)->i_file_acl
) {
1528 bh
= sb_bread(inode
->i_sb
, EXT4_I(inode
)->i_file_acl
);
1532 if (ext4_xattr_check_block(inode
, bh
)) {
1533 EXT4_ERROR_INODE(inode
, "bad block %llu",
1534 EXT4_I(inode
)->i_file_acl
);
1535 error
= -EFSCORRUPTED
;
1539 end
= bh
->b_data
+ bh
->b_size
;
1540 min_offs
= end
- base
;
1541 bfree
= ext4_xattr_free_space(BFIRST(bh
), &min_offs
, base
,
1543 if (bfree
+ ifree
< isize_diff
) {
1544 if (!tried_min_extra_isize
&& s_min_extra_isize
) {
1545 tried_min_extra_isize
++;
1546 new_extra_isize
= s_min_extra_isize
;
1554 bfree
= inode
->i_sb
->s_blocksize
;
1557 error
= ext4_xattr_make_inode_space(handle
, inode
, raw_inode
,
1558 isize_diff
, ifree
, bfree
,
1561 if (error
== -ENOSPC
&& !tried_min_extra_isize
&&
1562 s_min_extra_isize
) {
1563 tried_min_extra_isize
++;
1564 new_extra_isize
= s_min_extra_isize
;
1571 /* Adjust the offsets and shift the remaining entries ahead */
1572 ext4_xattr_shift_entries(IFIRST(header
), EXT4_I(inode
)->i_extra_isize
1573 - new_extra_isize
, (void *)raw_inode
+
1574 EXT4_GOOD_OLD_INODE_SIZE
+ new_extra_isize
,
1575 (void *)header
, total_ino
);
1576 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
1579 ext4_write_unlock_xattr(inode
, &no_expand
);
1585 * Inode size expansion failed; don't try again
1588 ext4_write_unlock_xattr(inode
, &no_expand
);
1595 * ext4_xattr_delete_inode()
1597 * Free extended attribute resources associated with this inode. This
1598 * is called immediately before an inode is freed. We have exclusive
1599 * access to the inode.
1602 ext4_xattr_delete_inode(handle_t
*handle
, struct inode
*inode
)
1604 struct buffer_head
*bh
= NULL
;
1606 if (!EXT4_I(inode
)->i_file_acl
)
1608 bh
= sb_bread(inode
->i_sb
, EXT4_I(inode
)->i_file_acl
);
1610 EXT4_ERROR_INODE(inode
, "block %llu read error",
1611 EXT4_I(inode
)->i_file_acl
);
1614 if (BHDR(bh
)->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
) ||
1615 BHDR(bh
)->h_blocks
!= cpu_to_le32(1)) {
1616 EXT4_ERROR_INODE(inode
, "bad block %llu",
1617 EXT4_I(inode
)->i_file_acl
);
1620 ext4_xattr_release_block(handle
, inode
, bh
);
1621 EXT4_I(inode
)->i_file_acl
= 0;
1628 * ext4_xattr_cache_insert()
1630 * Create a new entry in the extended attribute cache, and insert
1631 * it unless such an entry is already in the cache.
1633 * Returns 0, or a negative error number on failure.
1636 ext4_xattr_cache_insert(struct mb_cache
*ext4_mb_cache
, struct buffer_head
*bh
)
1638 struct ext4_xattr_header
*header
= BHDR(bh
);
1639 __u32 hash
= le32_to_cpu(header
->h_hash
);
1640 int reusable
= le32_to_cpu(header
->h_refcount
) <
1641 EXT4_XATTR_REFCOUNT_MAX
;
1644 error
= mb_cache_entry_create(ext4_mb_cache
, GFP_NOFS
, hash
,
1645 bh
->b_blocknr
, reusable
);
1647 if (error
== -EBUSY
)
1648 ea_bdebug(bh
, "already in cache");
1650 ea_bdebug(bh
, "inserting [%x]", (int)hash
);
1656 * Compare two extended attribute blocks for equality.
1658 * Returns 0 if the blocks are equal, 1 if they differ, and
1659 * a negative error number on errors.
1662 ext4_xattr_cmp(struct ext4_xattr_header
*header1
,
1663 struct ext4_xattr_header
*header2
)
1665 struct ext4_xattr_entry
*entry1
, *entry2
;
1667 entry1
= ENTRY(header1
+1);
1668 entry2
= ENTRY(header2
+1);
1669 while (!IS_LAST_ENTRY(entry1
)) {
1670 if (IS_LAST_ENTRY(entry2
))
1672 if (entry1
->e_hash
!= entry2
->e_hash
||
1673 entry1
->e_name_index
!= entry2
->e_name_index
||
1674 entry1
->e_name_len
!= entry2
->e_name_len
||
1675 entry1
->e_value_size
!= entry2
->e_value_size
||
1676 memcmp(entry1
->e_name
, entry2
->e_name
, entry1
->e_name_len
))
1678 if (entry1
->e_value_block
!= 0 || entry2
->e_value_block
!= 0)
1679 return -EFSCORRUPTED
;
1680 if (memcmp((char *)header1
+ le16_to_cpu(entry1
->e_value_offs
),
1681 (char *)header2
+ le16_to_cpu(entry2
->e_value_offs
),
1682 le32_to_cpu(entry1
->e_value_size
)))
1685 entry1
= EXT4_XATTR_NEXT(entry1
);
1686 entry2
= EXT4_XATTR_NEXT(entry2
);
1688 if (!IS_LAST_ENTRY(entry2
))
1694 * ext4_xattr_cache_find()
1696 * Find an identical extended attribute block.
1698 * Returns a pointer to the block found, or NULL if such a block was
1699 * not found or an error occurred.
1701 static struct buffer_head
*
1702 ext4_xattr_cache_find(struct inode
*inode
, struct ext4_xattr_header
*header
,
1703 struct mb_cache_entry
**pce
)
1705 __u32 hash
= le32_to_cpu(header
->h_hash
);
1706 struct mb_cache_entry
*ce
;
1707 struct mb_cache
*ext4_mb_cache
= EXT4_GET_MB_CACHE(inode
);
1709 if (!header
->h_hash
)
1710 return NULL
; /* never share */
1711 ea_idebug(inode
, "looking for cached blocks [%x]", (int)hash
);
1712 ce
= mb_cache_entry_find_first(ext4_mb_cache
, hash
);
1714 struct buffer_head
*bh
;
1716 bh
= sb_bread(inode
->i_sb
, ce
->e_block
);
1718 EXT4_ERROR_INODE(inode
, "block %lu read error",
1719 (unsigned long) ce
->e_block
);
1720 } else if (ext4_xattr_cmp(header
, BHDR(bh
)) == 0) {
1725 ce
= mb_cache_entry_find_next(ext4_mb_cache
, ce
);
1730 #define NAME_HASH_SHIFT 5
1731 #define VALUE_HASH_SHIFT 16
1734 * ext4_xattr_hash_entry()
1736 * Compute the hash of an extended attribute.
1738 static inline void ext4_xattr_hash_entry(struct ext4_xattr_header
*header
,
1739 struct ext4_xattr_entry
*entry
)
1742 char *name
= entry
->e_name
;
1745 for (n
= 0; n
< entry
->e_name_len
; n
++) {
1746 hash
= (hash
<< NAME_HASH_SHIFT
) ^
1747 (hash
>> (8*sizeof(hash
) - NAME_HASH_SHIFT
)) ^
1751 if (entry
->e_value_size
!= 0) {
1752 __le32
*value
= (__le32
*)((char *)header
+
1753 le16_to_cpu(entry
->e_value_offs
));
1754 for (n
= (le32_to_cpu(entry
->e_value_size
) +
1755 EXT4_XATTR_ROUND
) >> EXT4_XATTR_PAD_BITS
; n
; n
--) {
1756 hash
= (hash
<< VALUE_HASH_SHIFT
) ^
1757 (hash
>> (8*sizeof(hash
) - VALUE_HASH_SHIFT
)) ^
1758 le32_to_cpu(*value
++);
1761 entry
->e_hash
= cpu_to_le32(hash
);
1764 #undef NAME_HASH_SHIFT
1765 #undef VALUE_HASH_SHIFT
1767 #define BLOCK_HASH_SHIFT 16
1770 * ext4_xattr_rehash()
1772 * Re-compute the extended attribute hash value after an entry has changed.
1774 static void ext4_xattr_rehash(struct ext4_xattr_header
*header
,
1775 struct ext4_xattr_entry
*entry
)
1777 struct ext4_xattr_entry
*here
;
1780 ext4_xattr_hash_entry(header
, entry
);
1781 here
= ENTRY(header
+1);
1782 while (!IS_LAST_ENTRY(here
)) {
1783 if (!here
->e_hash
) {
1784 /* Block is not shared if an entry's hash value == 0 */
1788 hash
= (hash
<< BLOCK_HASH_SHIFT
) ^
1789 (hash
>> (8*sizeof(hash
) - BLOCK_HASH_SHIFT
)) ^
1790 le32_to_cpu(here
->e_hash
);
1791 here
= EXT4_XATTR_NEXT(here
);
1793 header
->h_hash
= cpu_to_le32(hash
);
1796 #undef BLOCK_HASH_SHIFT
1798 #define HASH_BUCKET_BITS 10
1801 ext4_xattr_create_cache(void)
1803 return mb_cache_create(HASH_BUCKET_BITS
);
1806 void ext4_xattr_destroy_cache(struct mb_cache
*cache
)
1809 mb_cache_destroy(cache
);