4 On-disk format of extended attributes for the ext4 filesystem.
6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
9 #include <linux/xattr.h>
11 /* Magic value in attribute blocks */
12 #define EXT4_XATTR_MAGIC 0xEA020000
14 /* Maximum number of references to one attribute block */
15 #define EXT4_XATTR_REFCOUNT_MAX 1024
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 #define EXT4_XATTR_INDEX_RICHACL 7
26 struct ext4_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 */
34 struct ext4_xattr_ibody_header {
35 __le32 h_magic; /* magic number for identification */
38 struct ext4_xattr_entry {
39 __u8 e_name_len; /* length of name */
40 __u8 e_name_index; /* attribute name index */
41 __le16 e_value_offs; /* offset in disk block of value */
42 __le32 e_value_block; /* disk block attribute is stored on (n/i) */
43 __le32 e_value_size; /* size of attribute value */
44 __le32 e_hash; /* hash value of name and value */
45 char e_name[0]; /* attribute name */
48 #define EXT4_XATTR_PAD_BITS 2
49 #define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
50 #define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
51 #define EXT4_XATTR_LEN(name_len) \
52 (((name_len) + EXT4_XATTR_ROUND + \
53 sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
54 #define EXT4_XATTR_NEXT(entry) \
55 ((struct ext4_xattr_entry *)( \
56 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
57 #define EXT4_XATTR_SIZE(size) \
58 (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
60 #define IHDR(inode, raw_inode) \
61 ((struct ext4_xattr_ibody_header *) \
62 ((void *)raw_inode + \
63 EXT4_GOOD_OLD_INODE_SIZE + \
64 EXT4_I(inode)->i_extra_isize))
65 #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
67 # ifdef CONFIG_EXT4_FS_XATTR
69 extern const struct xattr_handler ext4_xattr_user_handler;
70 extern const struct xattr_handler ext4_xattr_trusted_handler;
71 extern const struct xattr_handler ext4_xattr_acl_access_handler;
72 extern const struct xattr_handler ext4_xattr_acl_default_handler;
73 extern const struct xattr_handler ext4_xattr_security_handler;
74 extern const struct xattr_handler ext4_xattr_acl_access_handler;
75 extern const struct xattr_handler ext4_xattr_acl_default_handler;
76 extern const struct xattr_handler ext4_xattr_security_handler;
77 extern const struct xattr_handler ext4_richacl_xattr_handler;
79 extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
81 extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
82 extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
83 extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
85 extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
86 extern void ext4_xattr_put_super(struct super_block *);
88 extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
89 struct ext4_inode *raw_inode, handle_t *handle);
91 extern int __init ext4_init_xattr(void);
92 extern void ext4_exit_xattr(void);
94 extern const struct xattr_handler *ext4_xattr_handlers[];
96 # else /* CONFIG_EXT4_FS_XATTR */
99 ext4_xattr_get(struct inode *inode, int name_index, const char *name,
100 void *buffer, size_t size, int flags)
106 ext4_xattr_set(struct inode *inode, int name_index, const char *name,
107 const void *value, size_t size, int flags)
113 ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
114 const char *name, const void *value, size_t size, int flags)
120 ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
125 ext4_xattr_put_super(struct super_block *sb)
129 static __init inline int
130 ext4_init_xattr(void)
136 ext4_exit_xattr(void)
141 ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
142 struct ext4_inode *raw_inode, handle_t *handle)
147 #define ext4_xattr_handlers NULL
149 # endif /* CONFIG_EXT4_FS_XATTR */
151 #ifdef CONFIG_EXT4_FS_SECURITY
152 extern int ext4_init_security(handle_t *handle, struct inode *inode,
153 struct inode *dir, const struct qstr *qstr);
155 static inline int ext4_init_security(handle_t *handle, struct inode *inode,
156 struct inode *dir, const struct qstr *qstr)