1*1da177e4SLinus Torvalds /* 2*1da177e4SLinus Torvalds File: linux/ext2_xattr.h 3*1da177e4SLinus Torvalds 4*1da177e4SLinus Torvalds On-disk format of extended attributes for the ext2 filesystem. 5*1da177e4SLinus Torvalds 6*1da177e4SLinus Torvalds (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> 7*1da177e4SLinus Torvalds */ 8*1da177e4SLinus Torvalds 9*1da177e4SLinus Torvalds #include <linux/config.h> 10*1da177e4SLinus Torvalds #include <linux/init.h> 11*1da177e4SLinus Torvalds #include <linux/xattr.h> 12*1da177e4SLinus Torvalds 13*1da177e4SLinus Torvalds /* Magic value in attribute blocks */ 14*1da177e4SLinus Torvalds #define EXT2_XATTR_MAGIC 0xEA020000 15*1da177e4SLinus Torvalds 16*1da177e4SLinus Torvalds /* Maximum number of references to one attribute block */ 17*1da177e4SLinus Torvalds #define EXT2_XATTR_REFCOUNT_MAX 1024 18*1da177e4SLinus Torvalds 19*1da177e4SLinus Torvalds /* Name indexes */ 20*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_USER 1 21*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2 22*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3 23*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_TRUSTED 4 24*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_LUSTRE 5 25*1da177e4SLinus Torvalds #define EXT2_XATTR_INDEX_SECURITY 6 26*1da177e4SLinus Torvalds 27*1da177e4SLinus Torvalds struct ext2_xattr_header { 28*1da177e4SLinus Torvalds __le32 h_magic; /* magic number for identification */ 29*1da177e4SLinus Torvalds __le32 h_refcount; /* reference count */ 30*1da177e4SLinus Torvalds __le32 h_blocks; /* number of disk blocks used */ 31*1da177e4SLinus Torvalds __le32 h_hash; /* hash value of all attributes */ 32*1da177e4SLinus Torvalds __u32 h_reserved[4]; /* zero right now */ 33*1da177e4SLinus Torvalds }; 34*1da177e4SLinus Torvalds 35*1da177e4SLinus Torvalds struct ext2_xattr_entry { 36*1da177e4SLinus Torvalds __u8 e_name_len; /* length of name */ 37*1da177e4SLinus Torvalds __u8 e_name_index; /* attribute name index */ 38*1da177e4SLinus Torvalds __le16 e_value_offs; /* offset in disk block of value */ 39*1da177e4SLinus Torvalds __le32 e_value_block; /* disk block attribute is stored on (n/i) */ 40*1da177e4SLinus Torvalds __le32 e_value_size; /* size of attribute value */ 41*1da177e4SLinus Torvalds __le32 e_hash; /* hash value of name and value */ 42*1da177e4SLinus Torvalds char e_name[0]; /* attribute name */ 43*1da177e4SLinus Torvalds }; 44*1da177e4SLinus Torvalds 45*1da177e4SLinus Torvalds #define EXT2_XATTR_PAD_BITS 2 46*1da177e4SLinus Torvalds #define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS) 47*1da177e4SLinus Torvalds #define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1) 48*1da177e4SLinus Torvalds #define EXT2_XATTR_LEN(name_len) \ 49*1da177e4SLinus Torvalds (((name_len) + EXT2_XATTR_ROUND + \ 50*1da177e4SLinus Torvalds sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND) 51*1da177e4SLinus Torvalds #define EXT2_XATTR_NEXT(entry) \ 52*1da177e4SLinus Torvalds ( (struct ext2_xattr_entry *)( \ 53*1da177e4SLinus Torvalds (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) ) 54*1da177e4SLinus Torvalds #define EXT2_XATTR_SIZE(size) \ 55*1da177e4SLinus Torvalds (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND) 56*1da177e4SLinus Torvalds 57*1da177e4SLinus Torvalds # ifdef CONFIG_EXT2_FS_XATTR 58*1da177e4SLinus Torvalds 59*1da177e4SLinus Torvalds extern struct xattr_handler ext2_xattr_user_handler; 60*1da177e4SLinus Torvalds extern struct xattr_handler ext2_xattr_trusted_handler; 61*1da177e4SLinus Torvalds extern struct xattr_handler ext2_xattr_acl_access_handler; 62*1da177e4SLinus Torvalds extern struct xattr_handler ext2_xattr_acl_default_handler; 63*1da177e4SLinus Torvalds extern struct xattr_handler ext2_xattr_security_handler; 64*1da177e4SLinus Torvalds 65*1da177e4SLinus Torvalds extern ssize_t ext2_listxattr(struct dentry *, char *, size_t); 66*1da177e4SLinus Torvalds 67*1da177e4SLinus Torvalds extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t); 68*1da177e4SLinus Torvalds extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int); 69*1da177e4SLinus Torvalds 70*1da177e4SLinus Torvalds extern void ext2_xattr_delete_inode(struct inode *); 71*1da177e4SLinus Torvalds extern void ext2_xattr_put_super(struct super_block *); 72*1da177e4SLinus Torvalds 73*1da177e4SLinus Torvalds extern int init_ext2_xattr(void); 74*1da177e4SLinus Torvalds extern void exit_ext2_xattr(void); 75*1da177e4SLinus Torvalds 76*1da177e4SLinus Torvalds extern struct xattr_handler *ext2_xattr_handlers[]; 77*1da177e4SLinus Torvalds 78*1da177e4SLinus Torvalds # else /* CONFIG_EXT2_FS_XATTR */ 79*1da177e4SLinus Torvalds 80*1da177e4SLinus Torvalds static inline int 81*1da177e4SLinus Torvalds ext2_xattr_get(struct inode *inode, int name_index, 82*1da177e4SLinus Torvalds const char *name, void *buffer, size_t size) 83*1da177e4SLinus Torvalds { 84*1da177e4SLinus Torvalds return -EOPNOTSUPP; 85*1da177e4SLinus Torvalds } 86*1da177e4SLinus Torvalds 87*1da177e4SLinus Torvalds static inline int 88*1da177e4SLinus Torvalds ext2_xattr_set(struct inode *inode, int name_index, const char *name, 89*1da177e4SLinus Torvalds const void *value, size_t size, int flags) 90*1da177e4SLinus Torvalds { 91*1da177e4SLinus Torvalds return -EOPNOTSUPP; 92*1da177e4SLinus Torvalds } 93*1da177e4SLinus Torvalds 94*1da177e4SLinus Torvalds static inline void 95*1da177e4SLinus Torvalds ext2_xattr_delete_inode(struct inode *inode) 96*1da177e4SLinus Torvalds { 97*1da177e4SLinus Torvalds } 98*1da177e4SLinus Torvalds 99*1da177e4SLinus Torvalds static inline void 100*1da177e4SLinus Torvalds ext2_xattr_put_super(struct super_block *sb) 101*1da177e4SLinus Torvalds { 102*1da177e4SLinus Torvalds } 103*1da177e4SLinus Torvalds 104*1da177e4SLinus Torvalds static inline int 105*1da177e4SLinus Torvalds init_ext2_xattr(void) 106*1da177e4SLinus Torvalds { 107*1da177e4SLinus Torvalds return 0; 108*1da177e4SLinus Torvalds } 109*1da177e4SLinus Torvalds 110*1da177e4SLinus Torvalds static inline void 111*1da177e4SLinus Torvalds exit_ext2_xattr(void) 112*1da177e4SLinus Torvalds { 113*1da177e4SLinus Torvalds } 114*1da177e4SLinus Torvalds 115*1da177e4SLinus Torvalds #define ext2_xattr_handlers NULL 116*1da177e4SLinus Torvalds 117*1da177e4SLinus Torvalds # endif /* CONFIG_EXT2_FS_XATTR */ 118*1da177e4SLinus Torvalds 119