2 File: linux/ext2_xattr.h
4 On-disk format of extended attributes for the ext2 filesystem.
6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
9 #include <linux/config.h>
10 #include <linux/init.h>
11 #include <linux/xattr.h>
13 /* Magic value in attribute blocks */
14 #define EXT2_XATTR_MAGIC 0xEA020000
16 /* Maximum number of references to one attribute block */
17 #define EXT2_XATTR_REFCOUNT_MAX 1024
20 #define EXT2_XATTR_INDEX_MAX 10
21 #define EXT2_XATTR_INDEX_USER 1
22 #define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
23 #define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
24 #define EXT2_XATTR_INDEX_TRUSTED 4
25 #define EXT2_XATTR_INDEX_LUSTRE 5
26 #define EXT2_XATTR_INDEX_SECURITY 6
28 struct ext2_xattr_header
{
29 __le32 h_magic
; /* magic number for identification */
30 __le32 h_refcount
; /* reference count */
31 __le32 h_blocks
; /* number of disk blocks used */
32 __le32 h_hash
; /* hash value of all attributes */
33 __u32 h_reserved
[4]; /* zero right now */
36 struct ext2_xattr_entry
{
37 __u8 e_name_len
; /* length of name */
38 __u8 e_name_index
; /* attribute name index */
39 __le16 e_value_offs
; /* offset in disk block of value */
40 __le32 e_value_block
; /* disk block attribute is stored on (n/i) */
41 __le32 e_value_size
; /* size of attribute value */
42 __le32 e_hash
; /* hash value of name and value */
43 char e_name
[0]; /* attribute name */
46 #define EXT2_XATTR_PAD_BITS 2
47 #define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)
48 #define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)
49 #define EXT2_XATTR_LEN(name_len) \
50 (((name_len) + EXT2_XATTR_ROUND + \
51 sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
52 #define EXT2_XATTR_NEXT(entry) \
53 ( (struct ext2_xattr_entry *)( \
54 (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
55 #define EXT2_XATTR_SIZE(size) \
56 (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)
58 # ifdef CONFIG_EXT2_FS_XATTR
60 struct ext2_xattr_handler
{
62 size_t (*list
)(char *list
, struct inode
*inode
, const char *name
,
64 int (*get
)(struct inode
*inode
, const char *name
, void *buffer
,
66 int (*set
)(struct inode
*inode
, const char *name
, const void *buffer
,
67 size_t size
, int flags
);
70 extern int ext2_xattr_register(int, struct ext2_xattr_handler
*);
71 extern void ext2_xattr_unregister(int, struct ext2_xattr_handler
*);
73 extern int ext2_setxattr(struct dentry
*, const char *, const void *, size_t, int);
74 extern ssize_t
ext2_getxattr(struct dentry
*, const char *, void *, size_t);
75 extern ssize_t
ext2_listxattr(struct dentry
*, char *, size_t);
76 extern int ext2_removexattr(struct dentry
*, const char *);
78 extern int ext2_xattr_get(struct inode
*, int, const char *, void *, size_t);
79 extern int ext2_xattr_list(struct inode
*, char *, size_t);
80 extern int ext2_xattr_set(struct inode
*, int, const char *, const void *, size_t, int);
82 extern void ext2_xattr_delete_inode(struct inode
*);
83 extern void ext2_xattr_put_super(struct super_block
*);
85 extern int init_ext2_xattr(void);
86 extern void exit_ext2_xattr(void);
88 # else /* CONFIG_EXT2_FS_XATTR */
89 # define ext2_setxattr NULL
90 # define ext2_getxattr NULL
91 # define ext2_listxattr NULL
92 # define ext2_removexattr NULL
95 ext2_xattr_get(struct inode
*inode
, int name_index
,
96 const char *name
, void *buffer
, size_t size
)
102 ext2_xattr_list(struct inode
*inode
, char *buffer
, size_t size
)
108 ext2_xattr_set(struct inode
*inode
, int name_index
, const char *name
,
109 const void *value
, size_t size
, int flags
)
115 ext2_xattr_delete_inode(struct inode
*inode
)
120 ext2_xattr_put_super(struct super_block
*sb
)
125 init_ext2_xattr(void)
131 exit_ext2_xattr(void)
135 # endif /* CONFIG_EXT2_FS_XATTR */
137 extern struct ext2_xattr_handler ext2_xattr_user_handler
;
138 extern struct ext2_xattr_handler ext2_xattr_trusted_handler
;
139 extern struct ext2_xattr_handler ext2_xattr_security_handler
;