xattr.h 7.42 KB
Newer Older
1
/*
2
  File: fs/ext4/xattr.h
3

4
  On-disk format of extended attributes for the ext4 filesystem.
5
6
7
8
9
10
11

  (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/

#include <linux/xattr.h>

/* 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
19
20
21
22
23
#define EXT4_XATTR_INDEX_USER			1
#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS	2
#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT	3
#define EXT4_XATTR_INDEX_TRUSTED		4
#define	EXT4_XATTR_INDEX_LUSTRE			5
#define EXT4_XATTR_INDEX_SECURITY	        6
24
#define EXT4_XATTR_INDEX_SYSTEM			7
25
26

struct ext4_xattr_header {
27
28
29
30
	__le32	h_magic;	/* magic number for identification */
	__le32	h_refcount;	/* reference count */
	__le32	h_blocks;	/* number of disk blocks used */
	__le32	h_hash;		/* hash value of all attributes */
31
32
33
	__le32	h_checksum;	/* crc32c(uuid+id+xattrblock) */
				/* id = inum if refcount=1, blknum otherwise */
	__u32	h_reserved[3];	/* zero right now */
34
35
};

36
struct ext4_xattr_ibody_header {
37
38
39
	__le32	h_magic;	/* magic number for identification */
};

40
struct ext4_xattr_entry {
41
42
43
44
45
46
47
48
49
	__u8	e_name_len;	/* length of name */
	__u8	e_name_index;	/* attribute name index */
	__le16	e_value_offs;	/* offset in disk block of value */
	__le32	e_value_block;	/* disk block attribute is stored on (n/i) */
	__le32	e_value_size;	/* size of attribute value */
	__le32	e_hash;		/* hash value of name and value */
	char	e_name[0];	/* attribute name */
};

50
51
52
53
54
55
56
#define EXT4_XATTR_PAD_BITS		2
#define EXT4_XATTR_PAD		(1<<EXT4_XATTR_PAD_BITS)
#define EXT4_XATTR_ROUND		(EXT4_XATTR_PAD-1)
#define EXT4_XATTR_LEN(name_len) \
	(((name_len) + EXT4_XATTR_ROUND + \
	sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
#define EXT4_XATTR_NEXT(entry) \
57
58
	((struct ext4_xattr_entry *)( \
	 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
59
60
#define EXT4_XATTR_SIZE(size) \
	(((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
61

62
63
64
65
66
67
68
#define IHDR(inode, raw_inode) \
	((struct ext4_xattr_ibody_header *) \
		((void *)raw_inode + \
		EXT4_GOOD_OLD_INODE_SIZE + \
		EXT4_I(inode)->i_extra_isize))
#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))

Tao Ma's avatar
Tao Ma committed
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
#define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data))
#define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr))
#define BFIRST(bh) ENTRY(BHDR(bh)+1)
#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)


struct ext4_xattr_info {
	int name_index;
	const char *name;
	const void *value;
	size_t value_len;
};

struct ext4_xattr_search {
	struct ext4_xattr_entry *first;
	void *base;
	void *end;
	struct ext4_xattr_entry *here;
	int not_found;
};

struct ext4_xattr_ibody_find {
	struct ext4_xattr_search s;
	struct ext4_iloc iloc;
};

Theodore Ts'o's avatar
Theodore Ts'o committed
95
# ifdef CONFIG_EXT4_FS_XATTR
96

97
98
99
100
101
extern const struct xattr_handler ext4_xattr_user_handler;
extern const struct xattr_handler ext4_xattr_trusted_handler;
extern const struct xattr_handler ext4_xattr_acl_access_handler;
extern const struct xattr_handler ext4_xattr_acl_default_handler;
extern const struct xattr_handler ext4_xattr_security_handler;
102

103
extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
104

105
106
107
extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
108

109
110
extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
extern void ext4_xattr_put_super(struct super_block *);
111

112
113
114
extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
			    struct ext4_inode *raw_inode, handle_t *handle);

115
116
extern int __init ext4_init_xattr(void);
extern void ext4_exit_xattr(void);
117

118
extern const struct xattr_handler *ext4_xattr_handlers[];
119

Tao Ma's avatar
Tao Ma committed
120
121
122
123
124
125
126
127
128
extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
				 struct ext4_xattr_ibody_find *is);
extern int ext4_xattr_ibody_get(struct inode *inode, int name_index,
				const char *name,
				void *buffer, size_t buffer_size);
extern int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
				struct ext4_xattr_info *i,
				struct ext4_xattr_ibody_find *is);

129
130
131
132
133
134
135
136
137
138
139
140
141
extern int ext4_has_inline_data(struct inode *inode);
extern int ext4_get_inline_size(struct inode *inode);
extern int ext4_get_max_inline_size(struct inode *inode);
extern int ext4_find_inline_data_nolock(struct inode *inode);
extern void ext4_write_inline_data(struct inode *inode,
				   struct ext4_iloc *iloc,
				   void *buffer, loff_t pos,
				   unsigned int len);
extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
				    unsigned int len);
extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
				 unsigned int len);
extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
142
143

extern int ext4_readpage_inline(struct inode *inode, struct page *page);
Theodore Ts'o's avatar
Theodore Ts'o committed
144
# else  /* CONFIG_EXT4_FS_XATTR */
145
146

static inline int
147
ext4_xattr_get(struct inode *inode, int name_index, const char *name,
148
149
150
151
152
153
	       void *buffer, size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static inline int
154
ext4_xattr_set(struct inode *inode, int name_index, const char *name,
155
156
157
158
159
160
	       const void *value, size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static inline int
161
ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
162
163
164
165
166
167
	       const char *name, const void *value, size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static inline void
168
ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
169
170
171
172
{
}

static inline void
173
ext4_xattr_put_super(struct super_block *sb)
174
175
176
{
}

177
static __init inline int
178
ext4_init_xattr(void)
179
180
181
182
183
{
	return 0;
}

static inline void
184
ext4_exit_xattr(void)
185
186
187
{
}

188
189
190
191
192
193
194
static inline int
ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
			    struct ext4_inode *raw_inode, handle_t *handle)
{
	return -EOPNOTSUPP;
}

195
#define ext4_xattr_handlers	NULL
196

Tao Ma's avatar
Tao Ma committed
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
static inline int
ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
		      struct ext4_xattr_ibody_find *is)
{
	return -EOPNOTSUPP;
}

static inline int
ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
		     struct ext4_xattr_info *i,
		     struct ext4_xattr_ibody_find *is)
{
	return -EOPNOTSUPP;
}

static inline int
ext4_xattr_ibody_get(struct inode *inode, int name_index,
		     const char *name,
		     void *buffer, size_t buffer_size)
{
	return -EOPNOTSUPP;
}

220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
static inline int ext4_find_inline_data_nolock(struct inode *inode)
{
	return 0;
}

static inline int ext4_has_inline_data(struct inode *inode)
{
	return 0;
}

static inline int ext4_get_inline_size(struct inode *inode)
{
	return 0;
}

static inline int ext4_get_max_inline_size(struct inode *inode)
{
	return 0;
}

static inline void ext4_write_inline_data(struct inode *inode,
					  struct ext4_iloc *iloc,
					  void *buffer, loff_t pos,
					  unsigned int len)
{
	return;
}

static inline int ext4_init_inline_data(handle_t *handle,
					struct inode *inode,
					unsigned int len)
{
	return 0;
}

static inline int ext4_destroy_inline_data(handle_t *handle,
					   struct inode *inode)
{
	return 0;
}
260
261
262
263
264

static inline int ext4_readpage_inline(struct inode *inode, struct page *page)
{
	return 0;
}
Theodore Ts'o's avatar
Theodore Ts'o committed
265
# endif  /* CONFIG_EXT4_FS_XATTR */
266

Theodore Ts'o's avatar
Theodore Ts'o committed
267
#ifdef CONFIG_EXT4_FS_SECURITY
268
extern int ext4_init_security(handle_t *handle, struct inode *inode,
269
			      struct inode *dir, const struct qstr *qstr);
270
#else
271
static inline int ext4_init_security(handle_t *handle, struct inode *inode,
272
				     struct inode *dir, const struct qstr *qstr)
273
274
275
276
{
	return 0;
}
#endif