diff options
Diffstat (limited to 'fs/ext4/xattr.h')
| -rw-r--r-- | fs/ext4/xattr.h | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h new file mode 100644 index 000000000000..79432b35398f --- /dev/null +++ b/fs/ext4/xattr.h @@ -0,0 +1,145 @@ +/* + 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) + +# ifdef CONFIG_EXT4DEV_FS_XATTR + +extern struct xattr_handler ext4_xattr_user_handler; +extern struct xattr_handler ext4_xattr_trusted_handler; +extern struct xattr_handler ext4_xattr_acl_access_handler; +extern struct xattr_handler ext4_xattr_acl_default_handler; +extern 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_list(struct inode *, char *, 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 init_ext4_xattr(void); +extern void exit_ext4_xattr(void); + +extern struct xattr_handler *ext4_xattr_handlers[]; + +# else /* CONFIG_EXT4DEV_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_list(struct inode *inode, void *buffer, size_t size) +{ + 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 inline int +init_ext4_xattr(void) +{ + return 0; +} + +static inline void +exit_ext4_xattr(void) +{ +} + +#define ext4_xattr_handlers NULL + +# endif /* CONFIG_EXT4DEV_FS_XATTR */ + +#ifdef CONFIG_EXT4DEV_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 |