Root/fs/ext3/xattr.h

1/*
2  File: fs/ext3/xattr.h
3
4  On-disk format of extended attributes for the ext3 filesystem.
5
6  (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
7*/
8
9#include <linux/xattr.h>
10
11/* Magic value in attribute blocks */
12#define EXT3_XATTR_MAGIC 0xEA020000
13
14/* Maximum number of references to one attribute block */
15#define EXT3_XATTR_REFCOUNT_MAX 1024
16
17/* Name indexes */
18#define EXT3_XATTR_INDEX_USER 1
19#define EXT3_XATTR_INDEX_POSIX_ACL_ACCESS 2
20#define EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT 3
21#define EXT3_XATTR_INDEX_TRUSTED 4
22#define EXT3_XATTR_INDEX_LUSTRE 5
23#define EXT3_XATTR_INDEX_SECURITY 6
24
25struct ext3_xattr_header {
26    __le32 h_magic; /* magic number for identification */
27    __le32 h_refcount; /* reference count */
28    __le32 h_blocks; /* number of disk blocks used */
29    __le32 h_hash; /* hash value of all attributes */
30    __u32 h_reserved[4]; /* zero right now */
31};
32
33struct ext3_xattr_ibody_header {
34    __le32 h_magic; /* magic number for identification */
35};
36
37struct ext3_xattr_entry {
38    __u8 e_name_len; /* length of name */
39    __u8 e_name_index; /* attribute name index */
40    __le16 e_value_offs; /* offset in disk block of value */
41    __le32 e_value_block; /* disk block attribute is stored on (n/i) */
42    __le32 e_value_size; /* size of attribute value */
43    __le32 e_hash; /* hash value of name and value */
44    char e_name[0]; /* attribute name */
45};
46
47#define EXT3_XATTR_PAD_BITS 2
48#define EXT3_XATTR_PAD (1<<EXT3_XATTR_PAD_BITS)
49#define EXT3_XATTR_ROUND (EXT3_XATTR_PAD-1)
50#define EXT3_XATTR_LEN(name_len) \
51    (((name_len) + EXT3_XATTR_ROUND + \
52    sizeof(struct ext3_xattr_entry)) & ~EXT3_XATTR_ROUND)
53#define EXT3_XATTR_NEXT(entry) \
54    ( (struct ext3_xattr_entry *)( \
55      (char *)(entry) + EXT3_XATTR_LEN((entry)->e_name_len)) )
56#define EXT3_XATTR_SIZE(size) \
57    (((size) + EXT3_XATTR_ROUND) & ~EXT3_XATTR_ROUND)
58
59# ifdef CONFIG_EXT3_FS_XATTR
60
61extern const struct xattr_handler ext3_xattr_user_handler;
62extern const struct xattr_handler ext3_xattr_trusted_handler;
63extern const struct xattr_handler ext3_xattr_acl_access_handler;
64extern const struct xattr_handler ext3_xattr_acl_default_handler;
65extern const struct xattr_handler ext3_xattr_security_handler;
66
67extern ssize_t ext3_listxattr(struct dentry *, char *, size_t);
68
69extern int ext3_xattr_get(struct inode *, int, const char *, void *, size_t);
70extern int ext3_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
71extern int ext3_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
72
73extern void ext3_xattr_delete_inode(handle_t *, struct inode *);
74extern void ext3_xattr_put_super(struct super_block *);
75
76extern int init_ext3_xattr(void);
77extern void exit_ext3_xattr(void);
78
79extern const struct xattr_handler *ext3_xattr_handlers[];
80
81# else /* CONFIG_EXT3_FS_XATTR */
82
83static inline int
84ext3_xattr_get(struct inode *inode, int name_index, const char *name,
85           void *buffer, size_t size, int flags)
86{
87    return -EOPNOTSUPP;
88}
89
90static inline int
91ext3_xattr_set(struct inode *inode, int name_index, const char *name,
92           const void *value, size_t size, int flags)
93{
94    return -EOPNOTSUPP;
95}
96
97static inline int
98ext3_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
99           const char *name, const void *value, size_t size, int flags)
100{
101    return -EOPNOTSUPP;
102}
103
104static inline void
105ext3_xattr_delete_inode(handle_t *handle, struct inode *inode)
106{
107}
108
109static inline void
110ext3_xattr_put_super(struct super_block *sb)
111{
112}
113
114static inline int
115init_ext3_xattr(void)
116{
117    return 0;
118}
119
120static inline void
121exit_ext3_xattr(void)
122{
123}
124
125#define ext3_xattr_handlers NULL
126
127# endif /* CONFIG_EXT3_FS_XATTR */
128
129#ifdef CONFIG_EXT3_FS_SECURITY
130extern int ext3_init_security(handle_t *handle, struct inode *inode,
131                  struct inode *dir, const struct qstr *qstr);
132#else
133static inline int ext3_init_security(handle_t *handle, struct inode *inode,
134                     struct inode *dir, const struct qstr *qstr)
135{
136    return 0;
137}
138#endif
139

Archive Download this file



interactive