Gitiles
Code Review Sign In
gerrit-public.fairphone.software / kernel / msm / 8cde0776ec1e86c270f65bf482f96288e6bf0023 / . / fs / ext2 / xattr.h
blob: 67cfeb66e897328869b1a34fb1c709b2aa356779 [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
9#include <linux/config.h>
10#include <linux/init.h>
11#include <linux/xattr.h>
12
13/* Magic value in attribute blocks */
14#define EXT2_XATTR_MAGIC 0xEA020000
15
16/* Maximum number of references to one attribute block */
17#define EXT2_XATTR_REFCOUNT_MAX 1024
18
19/* Name indexes */
20#define EXT2_XATTR_INDEX_USER 1
21#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
22#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
23#define EXT2_XATTR_INDEX_TRUSTED 4
24#define EXT2_XATTR_INDEX_LUSTRE 5
25#define EXT2_XATTR_INDEX_SECURITY 6
26
27struct ext2_xattr_header {
28 __le32 h_magic; /* magic number for identification */
29 __le32 h_refcount; /* reference count */
30 __le32 h_blocks; /* number of disk blocks used */
31 __le32 h_hash; /* hash value of all attributes */
32 __u32 h_reserved[4]; /* zero right now */
33};
34
35struct ext2_xattr_entry {
36 __u8 e_name_len; /* length of name */
37 __u8 e_name_index; /* attribute name index */
38 __le16 e_value_offs; /* offset in disk block of value */
39 __le32 e_value_block; /* disk block attribute is stored on (n/i) */
40 __le32 e_value_size; /* size of attribute value */
41 __le32 e_hash; /* hash value of name and value */
42 char e_name[0]; /* attribute name */
43};
44
45#define EXT2_XATTR_PAD_BITS 2
46#define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)
47#define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)
48#define EXT2_XATTR_LEN(name_len) \
49 (((name_len) + EXT2_XATTR_ROUND + \
50 sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
51#define EXT2_XATTR_NEXT(entry) \
52 ( (struct ext2_xattr_entry *)( \
53 (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
54#define EXT2_XATTR_SIZE(size) \
55 (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)
56
57# ifdef CONFIG_EXT2_FS_XATTR
58
59extern struct xattr_handler ext2_xattr_user_handler;
60extern struct xattr_handler ext2_xattr_trusted_handler;
61extern struct xattr_handler ext2_xattr_acl_access_handler;
62extern struct xattr_handler ext2_xattr_acl_default_handler;
63extern struct xattr_handler ext2_xattr_security_handler;
64
65extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);
66
67extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);
68extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
69
70extern void ext2_xattr_delete_inode(struct inode *);
71extern void ext2_xattr_put_super(struct super_block *);
72
73extern int init_ext2_xattr(void);
74extern void exit_ext2_xattr(void);
75
76extern struct xattr_handler *ext2_xattr_handlers[];
77
78# else /* CONFIG_EXT2_FS_XATTR */
79
80static inline int
81ext2_xattr_get(struct inode *inode, int name_index,
82 const char *name, void *buffer, size_t size)
83{
84 return -EOPNOTSUPP;
85}
86
87static inline int
88ext2_xattr_set(struct inode *inode, int name_index, const char *name,
89 const void *value, size_t size, int flags)
90{
91 return -EOPNOTSUPP;
92}
93
94static inline void
95ext2_xattr_delete_inode(struct inode *inode)
96{
97}
98
99static inline void
100ext2_xattr_put_super(struct super_block *sb)
101{
102}
103
104static inline int
105init_ext2_xattr(void)
106{
107 return 0;
108}
109
110static inline void
111exit_ext2_xattr(void)
112{
113}
114
115#define ext2_xattr_handlers NULL
116
117# endif /* CONFIG_EXT2_FS_XATTR */
118
Stephen Smalley10f47e62005-09-09 13:01:39 -0700[diff] [blame]119#ifdef CONFIG_EXT2_FS_SECURITY
120extern int ext2_init_security(struct inode *inode, struct inode *dir);
121#else
122static inline int ext2_init_security(struct inode *inode, struct inode *dir)
123{
124 return 0;
125}
126#endif