Gitiles
Code Review Sign In
gerrit-public.fairphone.software / kernel / msm-4.9 / b9b1f8d5930a813879278d0cbfc8c658d6a038dc / . / fs / ext2 / xattr.h
blob: bf8175b2ced95ed1cb69ed541f76437dbe2f29f0 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/*
2 File: linux/ext2_xattr.h
3
4 On-disk format of extended attributes for the ext2 filesystem.
5
6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
7*/
8
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]9#include <linux/init.h>
10#include <linux/xattr.h>
11
12/* Magic value in attribute blocks */
13#define EXT2_XATTR_MAGIC 0xEA020000
14
15/* Maximum number of references to one attribute block */
16#define EXT2_XATTR_REFCOUNT_MAX 1024
17
18/* Name indexes */
19#define EXT2_XATTR_INDEX_USER 1
20#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
21#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
22#define EXT2_XATTR_INDEX_TRUSTED 4
23#define EXT2_XATTR_INDEX_LUSTRE 5
24#define EXT2_XATTR_INDEX_SECURITY 6
25
26struct ext2_xattr_header {
27 __le32 h_magic; /* magic number for identification */
28 __le32 h_refcount; /* reference count */
29 __le32 h_blocks; /* number of disk blocks used */
30 __le32 h_hash; /* hash value of all attributes */
31 __u32 h_reserved[4]; /* zero right now */
32};
33
34struct ext2_xattr_entry {
35 __u8 e_name_len; /* length of name */
36 __u8 e_name_index; /* attribute name index */
37 __le16 e_value_offs; /* offset in disk block of value */
38 __le32 e_value_block; /* disk block attribute is stored on (n/i) */
39 __le32 e_value_size; /* size of attribute value */
40 __le32 e_hash; /* hash value of name and value */
41 char e_name[0]; /* attribute name */
42};
43
44#define EXT2_XATTR_PAD_BITS 2
45#define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)
46#define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)
47#define EXT2_XATTR_LEN(name_len) \
48 (((name_len) + EXT2_XATTR_ROUND + \
49 sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
50#define EXT2_XATTR_NEXT(entry) \
51 ( (struct ext2_xattr_entry *)( \
52 (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
53#define EXT2_XATTR_SIZE(size) \
54 (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)
55
56# ifdef CONFIG_EXT2_FS_XATTR
57
58extern struct xattr_handler ext2_xattr_user_handler;
59extern struct xattr_handler ext2_xattr_trusted_handler;
60extern struct xattr_handler ext2_xattr_acl_access_handler;
61extern struct xattr_handler ext2_xattr_acl_default_handler;
62extern struct xattr_handler ext2_xattr_security_handler;
63
64extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);
65
66extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);
67extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
68
69extern void ext2_xattr_delete_inode(struct inode *);
70extern void ext2_xattr_put_super(struct super_block *);
71
72extern int init_ext2_xattr(void);
73extern void exit_ext2_xattr(void);
74
75extern struct xattr_handler *ext2_xattr_handlers[];
76
77# else /* CONFIG_EXT2_FS_XATTR */
78
79static inline int
80ext2_xattr_get(struct inode *inode, int name_index,
81 const char *name, void *buffer, size_t size)
82{
83 return -EOPNOTSUPP;
84}
85
86static inline int
87ext2_xattr_set(struct inode *inode, int name_index, const char *name,
88 const void *value, size_t size, int flags)
89{
90 return -EOPNOTSUPP;
91}
92
93static inline void
94ext2_xattr_delete_inode(struct inode *inode)
95{
96}
97
98static inline void
99ext2_xattr_put_super(struct super_block *sb)
100{
101}
102
103static inline int
104init_ext2_xattr(void)
105{
106 return 0;
107}
108
109static inline void
110exit_ext2_xattr(void)
111{
112}
113
114#define ext2_xattr_handlers NULL
115
116# endif /* CONFIG_EXT2_FS_XATTR */
117
Stephen Smalley10f47e62005-09-09 13:01:39 -0700[diff] [blame]118#ifdef CONFIG_EXT2_FS_SECURITY
119extern int ext2_init_security(struct inode *inode, struct inode *dir);
120#else
121static inline int ext2_init_security(struct inode *inode, struct inode *dir)
122{
123 return 0;
124}
125#endif