blob: ca309c0d03ecb9d99f91210576ce62971ddd473d
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | File: linux/ext2_ext_attr.h |
4 | |
5 | On-disk format of extended attributes for the ext2 filesystem. |
6 | |
7 | (C) 2000 Andreas Gruenbacher, <a.gruenbacher@computer.org> |
8 | */ |
9 | |
10 | /* Magic value in attribute blocks */ |
11 | #define EXT2_EXT_ATTR_MAGIC_v1 0xEA010000 |
12 | #define EXT2_EXT_ATTR_MAGIC 0xEA020000 |
13 | |
14 | /* Maximum number of references to one attribute block */ |
15 | #define EXT2_EXT_ATTR_REFCOUNT_MAX 1024 |
16 | |
17 | struct ext2_ext_attr_header { |
18 | __u32 h_magic; /* magic number for identification */ |
19 | __u32 h_refcount; /* reference count */ |
20 | __u32 h_blocks; /* number of disk blocks used */ |
21 | __u32 h_hash; /* hash value of all attributes */ |
22 | __u32 h_reserved[4]; /* zero right now */ |
23 | }; |
24 | |
25 | struct ext2_ext_attr_entry { |
26 | __u8 e_name_len; /* length of name */ |
27 | __u8 e_name_index; /* attribute name index */ |
28 | __u16 e_value_offs; /* offset in disk block of value */ |
29 | __u32 e_value_block; /* disk block attribute is stored on (n/i) */ |
30 | __u32 e_value_size; /* size of attribute value */ |
31 | __u32 e_hash; /* hash value of name and value */ |
32 | }; |
33 | |
34 | #define EXT2_EXT_ATTR_PAD_BITS 2 |
35 | #define EXT2_EXT_ATTR_PAD (1<<EXT2_EXT_ATTR_PAD_BITS) |
36 | #define EXT2_EXT_ATTR_ROUND (EXT2_EXT_ATTR_PAD-1) |
37 | #define EXT2_EXT_ATTR_LEN(name_len) \ |
38 | (((name_len) + EXT2_EXT_ATTR_ROUND + \ |
39 | sizeof(struct ext2_ext_attr_entry)) & ~EXT2_EXT_ATTR_ROUND) |
40 | #define EXT2_EXT_ATTR_NEXT(entry) \ |
41 | ( (struct ext2_ext_attr_entry *)( \ |
42 | (char *)(entry) + EXT2_EXT_ATTR_LEN((entry)->e_name_len)) ) |
43 | #define EXT2_EXT_ATTR_SIZE(size) \ |
44 | (((size) + EXT2_EXT_ATTR_ROUND) & ~EXT2_EXT_ATTR_ROUND) |
45 | #define EXT2_EXT_IS_LAST_ENTRY(entry) (*((__u32 *)(entry)) == 0UL) |
46 | #define EXT2_EXT_ATTR_NAME(entry) \ |
47 | (((char *) (entry)) + sizeof(struct ext2_ext_attr_entry)) |
48 | #define EXT2_XATTR_LEN(name_len) \ |
49 | (((name_len) + EXT2_EXT_ATTR_ROUND + \ |
50 | sizeof(struct ext2_xattr_entry)) & ~EXT2_EXT_ATTR_ROUND) |
51 | #define EXT2_XATTR_SIZE(size) \ |
52 | (((size) + EXT2_EXT_ATTR_ROUND) & ~EXT2_EXT_ATTR_ROUND) |
53 |