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Linux kernel mirror (for testing)
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linux
1/*
2 File: fs/ext4/xattr.h
3
4 On-disk format of extended attributes for the ext4 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 EXT4_XATTR_MAGIC 0xEA020000
13
14/* Maximum number of references to one attribute block */
15#define EXT4_XATTR_REFCOUNT_MAX 1024
16
17/* Name indexes */
18#define EXT4_XATTR_INDEX_USER 1
19#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2
20#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3
21#define EXT4_XATTR_INDEX_TRUSTED 4
22#define EXT4_XATTR_INDEX_LUSTRE 5
23#define EXT4_XATTR_INDEX_SECURITY 6
24
25struct ext4_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 ext4_xattr_ibody_header {
34 __le32 h_magic; /* magic number for identification */
35};
36
37struct ext4_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 EXT4_XATTR_PAD_BITS 2
48#define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
49#define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
50#define EXT4_XATTR_LEN(name_len) \
51 (((name_len) + EXT4_XATTR_ROUND + \
52 sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
53#define EXT4_XATTR_NEXT(entry) \
54 ( (struct ext4_xattr_entry *)( \
55 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)) )
56#define EXT4_XATTR_SIZE(size) \
57 (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
58
59#define IHDR(inode, raw_inode) \
60 ((struct ext4_xattr_ibody_header *) \
61 ((void *)raw_inode + \
62 EXT4_GOOD_OLD_INODE_SIZE + \
63 EXT4_I(inode)->i_extra_isize))
64#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
65
66# ifdef CONFIG_EXT4DEV_FS_XATTR
67
68extern struct xattr_handler ext4_xattr_user_handler;
69extern struct xattr_handler ext4_xattr_trusted_handler;
70extern struct xattr_handler ext4_xattr_acl_access_handler;
71extern struct xattr_handler ext4_xattr_acl_default_handler;
72extern struct xattr_handler ext4_xattr_security_handler;
73
74extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
75
76extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
77extern int ext4_xattr_list(struct inode *, char *, size_t);
78extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
79extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
80
81extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
82extern void ext4_xattr_put_super(struct super_block *);
83
84extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
85 struct ext4_inode *raw_inode, handle_t *handle);
86
87extern int init_ext4_xattr(void);
88extern void exit_ext4_xattr(void);
89
90extern struct xattr_handler *ext4_xattr_handlers[];
91
92# else /* CONFIG_EXT4DEV_FS_XATTR */
93
94static inline int
95ext4_xattr_get(struct inode *inode, int name_index, const char *name,
96 void *buffer, size_t size, int flags)
97{
98 return -EOPNOTSUPP;
99}
100
101static inline int
102ext4_xattr_list(struct inode *inode, void *buffer, size_t size)
103{
104 return -EOPNOTSUPP;
105}
106
107static inline int
108ext4_xattr_set(struct inode *inode, int name_index, const char *name,
109 const void *value, size_t size, int flags)
110{
111 return -EOPNOTSUPP;
112}
113
114static inline int
115ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
116 const char *name, const void *value, size_t size, int flags)
117{
118 return -EOPNOTSUPP;
119}
120
121static inline void
122ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
123{
124}
125
126static inline void
127ext4_xattr_put_super(struct super_block *sb)
128{
129}
130
131static inline int
132init_ext4_xattr(void)
133{
134 return 0;
135}
136
137static inline void
138exit_ext4_xattr(void)
139{
140}
141
142static inline int
143ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
144 struct ext4_inode *raw_inode, handle_t *handle)
145{
146 return -EOPNOTSUPP;
147}
148
149#define ext4_xattr_handlers NULL
150
151# endif /* CONFIG_EXT4DEV_FS_XATTR */
152
153#ifdef CONFIG_EXT4DEV_FS_SECURITY
154extern int ext4_init_security(handle_t *handle, struct inode *inode,
155 struct inode *dir);
156#else
157static inline int ext4_init_security(handle_t *handle, struct inode *inode,
158 struct inode *dir)
159{
160 return 0;
161}
162#endif