1ac27a0ecSDave Kleikamp /* 2617ba13bSMingming Cao File: fs/ext4/xattr.h 3ac27a0ecSDave Kleikamp 4617ba13bSMingming Cao On-disk format of extended attributes for the ext4 filesystem. 5ac27a0ecSDave Kleikamp 6ac27a0ecSDave Kleikamp (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> 7ac27a0ecSDave Kleikamp */ 8ac27a0ecSDave Kleikamp 9ac27a0ecSDave Kleikamp #include <linux/xattr.h> 10ac27a0ecSDave Kleikamp 11ac27a0ecSDave Kleikamp /* Magic value in attribute blocks */ 12617ba13bSMingming Cao #define EXT4_XATTR_MAGIC 0xEA020000 13ac27a0ecSDave Kleikamp 14ac27a0ecSDave Kleikamp /* Maximum number of references to one attribute block */ 15617ba13bSMingming Cao #define EXT4_XATTR_REFCOUNT_MAX 1024 16ac27a0ecSDave Kleikamp 17ac27a0ecSDave Kleikamp /* Name indexes */ 18617ba13bSMingming Cao #define EXT4_XATTR_INDEX_USER 1 19617ba13bSMingming Cao #define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2 20617ba13bSMingming Cao #define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3 21617ba13bSMingming Cao #define EXT4_XATTR_INDEX_TRUSTED 4 22617ba13bSMingming Cao #define EXT4_XATTR_INDEX_LUSTRE 5 23617ba13bSMingming Cao #define EXT4_XATTR_INDEX_SECURITY 6 24ac27a0ecSDave Kleikamp 25617ba13bSMingming Cao struct ext4_xattr_header { 26ac27a0ecSDave Kleikamp __le32 h_magic; /* magic number for identification */ 27ac27a0ecSDave Kleikamp __le32 h_refcount; /* reference count */ 28ac27a0ecSDave Kleikamp __le32 h_blocks; /* number of disk blocks used */ 29ac27a0ecSDave Kleikamp __le32 h_hash; /* hash value of all attributes */ 30ac27a0ecSDave Kleikamp __u32 h_reserved[4]; /* zero right now */ 31ac27a0ecSDave Kleikamp }; 32ac27a0ecSDave Kleikamp 33617ba13bSMingming Cao struct ext4_xattr_ibody_header { 34ac27a0ecSDave Kleikamp __le32 h_magic; /* magic number for identification */ 35ac27a0ecSDave Kleikamp }; 36ac27a0ecSDave Kleikamp 37617ba13bSMingming Cao struct ext4_xattr_entry { 38ac27a0ecSDave Kleikamp __u8 e_name_len; /* length of name */ 39ac27a0ecSDave Kleikamp __u8 e_name_index; /* attribute name index */ 40ac27a0ecSDave Kleikamp __le16 e_value_offs; /* offset in disk block of value */ 41ac27a0ecSDave Kleikamp __le32 e_value_block; /* disk block attribute is stored on (n/i) */ 42ac27a0ecSDave Kleikamp __le32 e_value_size; /* size of attribute value */ 43ac27a0ecSDave Kleikamp __le32 e_hash; /* hash value of name and value */ 44ac27a0ecSDave Kleikamp char e_name[0]; /* attribute name */ 45ac27a0ecSDave Kleikamp }; 46ac27a0ecSDave Kleikamp 47617ba13bSMingming Cao #define EXT4_XATTR_PAD_BITS 2 48617ba13bSMingming Cao #define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS) 49617ba13bSMingming Cao #define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1) 50617ba13bSMingming Cao #define EXT4_XATTR_LEN(name_len) \ 51617ba13bSMingming Cao (((name_len) + EXT4_XATTR_ROUND + \ 52617ba13bSMingming Cao sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND) 53617ba13bSMingming Cao #define EXT4_XATTR_NEXT(entry) \ 54617ba13bSMingming Cao ( (struct ext4_xattr_entry *)( \ 55617ba13bSMingming Cao (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)) ) 56617ba13bSMingming Cao #define EXT4_XATTR_SIZE(size) \ 57617ba13bSMingming Cao (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND) 58ac27a0ecSDave Kleikamp 59617ba13bSMingming Cao # ifdef CONFIG_EXT4DEV_FS_XATTR 60ac27a0ecSDave Kleikamp 61617ba13bSMingming Cao extern struct xattr_handler ext4_xattr_user_handler; 62617ba13bSMingming Cao extern struct xattr_handler ext4_xattr_trusted_handler; 63617ba13bSMingming Cao extern struct xattr_handler ext4_xattr_acl_access_handler; 64617ba13bSMingming Cao extern struct xattr_handler ext4_xattr_acl_default_handler; 65617ba13bSMingming Cao extern struct xattr_handler ext4_xattr_security_handler; 66ac27a0ecSDave Kleikamp 67617ba13bSMingming Cao extern ssize_t ext4_listxattr(struct dentry *, char *, size_t); 68ac27a0ecSDave Kleikamp 69617ba13bSMingming Cao extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t); 70617ba13bSMingming Cao extern int ext4_xattr_list(struct inode *, char *, size_t); 71617ba13bSMingming Cao extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int); 72617ba13bSMingming Cao extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int); 73ac27a0ecSDave Kleikamp 74617ba13bSMingming Cao extern void ext4_xattr_delete_inode(handle_t *, struct inode *); 75617ba13bSMingming Cao extern void ext4_xattr_put_super(struct super_block *); 76ac27a0ecSDave Kleikamp 77617ba13bSMingming Cao extern int init_ext4_xattr(void); 78617ba13bSMingming Cao extern void exit_ext4_xattr(void); 79ac27a0ecSDave Kleikamp 80617ba13bSMingming Cao extern struct xattr_handler *ext4_xattr_handlers[]; 81ac27a0ecSDave Kleikamp 82617ba13bSMingming Cao # else /* CONFIG_EXT4DEV_FS_XATTR */ 83ac27a0ecSDave Kleikamp 84ac27a0ecSDave Kleikamp static inline int 85617ba13bSMingming Cao ext4_xattr_get(struct inode *inode, int name_index, const char *name, 86ac27a0ecSDave Kleikamp void *buffer, size_t size, int flags) 87ac27a0ecSDave Kleikamp { 88ac27a0ecSDave Kleikamp return -EOPNOTSUPP; 89ac27a0ecSDave Kleikamp } 90ac27a0ecSDave Kleikamp 91ac27a0ecSDave Kleikamp static inline int 92617ba13bSMingming Cao ext4_xattr_list(struct inode *inode, void *buffer, size_t size) 93ac27a0ecSDave Kleikamp { 94ac27a0ecSDave Kleikamp return -EOPNOTSUPP; 95ac27a0ecSDave Kleikamp } 96ac27a0ecSDave Kleikamp 97ac27a0ecSDave Kleikamp static inline int 98617ba13bSMingming Cao ext4_xattr_set(struct inode *inode, int name_index, const char *name, 99ac27a0ecSDave Kleikamp const void *value, size_t size, int flags) 100ac27a0ecSDave Kleikamp { 101ac27a0ecSDave Kleikamp return -EOPNOTSUPP; 102ac27a0ecSDave Kleikamp } 103ac27a0ecSDave Kleikamp 104ac27a0ecSDave Kleikamp static inline int 105617ba13bSMingming Cao ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, 106ac27a0ecSDave Kleikamp const char *name, const void *value, size_t size, int flags) 107ac27a0ecSDave Kleikamp { 108ac27a0ecSDave Kleikamp return -EOPNOTSUPP; 109ac27a0ecSDave Kleikamp } 110ac27a0ecSDave Kleikamp 111ac27a0ecSDave Kleikamp static inline void 112617ba13bSMingming Cao ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) 113ac27a0ecSDave Kleikamp { 114ac27a0ecSDave Kleikamp } 115ac27a0ecSDave Kleikamp 116ac27a0ecSDave Kleikamp static inline void 117617ba13bSMingming Cao ext4_xattr_put_super(struct super_block *sb) 118ac27a0ecSDave Kleikamp { 119ac27a0ecSDave Kleikamp } 120ac27a0ecSDave Kleikamp 121ac27a0ecSDave Kleikamp static inline int 122617ba13bSMingming Cao init_ext4_xattr(void) 123ac27a0ecSDave Kleikamp { 124ac27a0ecSDave Kleikamp return 0; 125ac27a0ecSDave Kleikamp } 126ac27a0ecSDave Kleikamp 127ac27a0ecSDave Kleikamp static inline void 128617ba13bSMingming Cao exit_ext4_xattr(void) 129ac27a0ecSDave Kleikamp { 130ac27a0ecSDave Kleikamp } 131ac27a0ecSDave Kleikamp 132617ba13bSMingming Cao #define ext4_xattr_handlers NULL 133ac27a0ecSDave Kleikamp 134617ba13bSMingming Cao # endif /* CONFIG_EXT4DEV_FS_XATTR */ 135ac27a0ecSDave Kleikamp 136617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_SECURITY 137617ba13bSMingming Cao extern int ext4_init_security(handle_t *handle, struct inode *inode, 138ac27a0ecSDave Kleikamp struct inode *dir); 139ac27a0ecSDave Kleikamp #else 140617ba13bSMingming Cao static inline int ext4_init_security(handle_t *handle, struct inode *inode, 141ac27a0ecSDave Kleikamp struct inode *dir) 142ac27a0ecSDave Kleikamp { 143ac27a0ecSDave Kleikamp return 0; 144ac27a0ecSDave Kleikamp } 145ac27a0ecSDave Kleikamp #endif 146