linux/fs/ext4/xattr.h

156 lines
4.3 KiB
C

/*
File: fs/ext4/xattr.h
On-disk format of extended attributes for the ext4 filesystem.
(C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/
#include <linux/xattr.h>
/* Magic value in attribute blocks */
#define EXT4_XATTR_MAGIC 0xEA020000
/* Maximum number of references to one attribute block */
#define EXT4_XATTR_REFCOUNT_MAX 1024
/* Name indexes */
#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
struct ext4_xattr_header {
__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 */
__u32 h_reserved[4]; /* zero right now */
};
struct ext4_xattr_ibody_header {
__le32 h_magic; /* magic number for identification */
};
struct ext4_xattr_entry {
__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 */
};
#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) \
((struct ext4_xattr_entry *)( \
(char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
#define EXT4_XATTR_SIZE(size) \
(((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
#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))
# ifdef CONFIG_EXT4_FS_XATTR
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;
extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
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);
extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
extern void ext4_xattr_put_super(struct super_block *);
extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
struct ext4_inode *raw_inode, handle_t *handle);
extern int __init ext4_init_xattr(void);
extern void ext4_exit_xattr(void);
extern const struct xattr_handler *ext4_xattr_handlers[];
# else /* CONFIG_EXT4_FS_XATTR */
static inline int
ext4_xattr_get(struct inode *inode, int name_index, const char *name,
void *buffer, size_t size, int flags)
{
return -EOPNOTSUPP;
}
static inline int
ext4_xattr_set(struct inode *inode, int name_index, const char *name,
const void *value, size_t size, int flags)
{
return -EOPNOTSUPP;
}
static inline int
ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
const char *name, const void *value, size_t size, int flags)
{
return -EOPNOTSUPP;
}
static inline void
ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
{
}
static inline void
ext4_xattr_put_super(struct super_block *sb)
{
}
static __init inline int
ext4_init_xattr(void)
{
return 0;
}
static inline void
ext4_exit_xattr(void)
{
}
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;
}
#define ext4_xattr_handlers NULL
# endif /* CONFIG_EXT4_FS_XATTR */
#ifdef CONFIG_EXT4_FS_SECURITY
extern int ext4_init_security(handle_t *handle, struct inode *inode,
struct inode *dir);
#else
static inline int ext4_init_security(handle_t *handle, struct inode *inode,
struct inode *dir)
{
return 0;
}
#endif