1 /* 2 File: fs/ext4/xattr.h 3 4 On-disk format of extended attributes for the ext4 filesystem. 5 6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> 7 */ 8 9 #include <linux/xattr.h> 10 11 /* Magic value in attribute blocks */ 12 #define EXT4_XATTR_MAGIC 0xEA020000 13 14 /* Maximum number of references to one attribute block */ 15 #define EXT4_XATTR_REFCOUNT_MAX 1024 16 17 /* Name indexes */ 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_SYSTEM 7 25 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 __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */ 32 /* id = inum if refcount=1, blknum otherwise */ 33 __u32 h_reserved[3]; /* zero right now */ 34 }; 35 36 struct ext4_xattr_ibody_header { 37 __le32 h_magic; /* magic number for identification */ 38 }; 39 40 struct ext4_xattr_entry { 41 __u8 e_name_len; /* length of name */ 42 __u8 e_name_index; /* attribute name index */ 43 __le16 e_value_offs; /* offset in disk block of value */ 44 __le32 e_value_block; /* disk block attribute is stored on (n/i) */ 45 __le32 e_value_size; /* size of attribute value */ 46 __le32 e_hash; /* hash value of name and value */ 47 char e_name[0]; /* attribute name */ 48 }; 49 50 #define EXT4_XATTR_PAD_BITS 2 51 #define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS) 52 #define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1) 53 #define EXT4_XATTR_LEN(name_len) \ 54 (((name_len) + EXT4_XATTR_ROUND + \ 55 sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND) 56 #define EXT4_XATTR_NEXT(entry) \ 57 ((struct ext4_xattr_entry *)( \ 58 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len))) 59 #define EXT4_XATTR_SIZE(size) \ 60 (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND) 61 62 #define IHDR(inode, raw_inode) \ 63 ((struct ext4_xattr_ibody_header *) \ 64 ((void *)raw_inode + \ 65 EXT4_GOOD_OLD_INODE_SIZE + \ 66 EXT4_I(inode)->i_extra_isize)) 67 #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) 68 69 #define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data)) 70 #define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr)) 71 #define BFIRST(bh) ENTRY(BHDR(bh)+1) 72 #define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) 73 74 #define EXT4_ZERO_XATTR_VALUE ((void *)-1) 75 76 struct ext4_xattr_info { 77 int name_index; 78 const char *name; 79 const void *value; 80 size_t value_len; 81 }; 82 83 struct ext4_xattr_search { 84 struct ext4_xattr_entry *first; 85 void *base; 86 void *end; 87 struct ext4_xattr_entry *here; 88 int not_found; 89 }; 90 91 struct ext4_xattr_ibody_find { 92 struct ext4_xattr_search s; 93 struct ext4_iloc iloc; 94 }; 95 96 extern const struct xattr_handler ext4_xattr_user_handler; 97 extern const struct xattr_handler ext4_xattr_trusted_handler; 98 extern const struct xattr_handler ext4_xattr_acl_access_handler; 99 extern const struct xattr_handler ext4_xattr_acl_default_handler; 100 extern const struct xattr_handler ext4_xattr_security_handler; 101 102 extern ssize_t ext4_listxattr(struct dentry *, char *, size_t); 103 104 extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t); 105 extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int); 106 extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int); 107 108 extern void ext4_xattr_delete_inode(handle_t *, struct inode *); 109 extern void ext4_xattr_put_super(struct super_block *); 110 111 extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, 112 struct ext4_inode *raw_inode, handle_t *handle); 113 114 extern int __init ext4_init_xattr(void); 115 extern void ext4_exit_xattr(void); 116 117 extern const struct xattr_handler *ext4_xattr_handlers[]; 118 119 extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, 120 struct ext4_xattr_ibody_find *is); 121 extern int ext4_xattr_ibody_get(struct inode *inode, int name_index, 122 const char *name, 123 void *buffer, size_t buffer_size); 124 extern int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, 125 struct ext4_xattr_info *i, 126 struct ext4_xattr_ibody_find *is); 127 128 extern int ext4_has_inline_data(struct inode *inode); 129 extern int ext4_get_inline_size(struct inode *inode); 130 extern int ext4_get_max_inline_size(struct inode *inode); 131 extern int ext4_find_inline_data_nolock(struct inode *inode); 132 extern void ext4_write_inline_data(struct inode *inode, 133 struct ext4_iloc *iloc, 134 void *buffer, loff_t pos, 135 unsigned int len); 136 extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode, 137 unsigned int len); 138 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode, 139 unsigned int len); 140 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode); 141 142 extern int ext4_readpage_inline(struct inode *inode, struct page *page); 143 extern int ext4_try_to_write_inline_data(struct address_space *mapping, 144 struct inode *inode, 145 loff_t pos, unsigned len, 146 unsigned flags, 147 struct page **pagep); 148 extern int ext4_write_inline_data_end(struct inode *inode, 149 loff_t pos, unsigned len, 150 unsigned copied, 151 struct page *page); 152 extern struct buffer_head * 153 ext4_journalled_write_inline_data(struct inode *inode, 154 unsigned len, 155 struct page *page); 156 extern int ext4_da_write_inline_data_begin(struct address_space *mapping, 157 struct inode *inode, 158 loff_t pos, unsigned len, 159 unsigned flags, 160 struct page **pagep, 161 void **fsdata); 162 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos, 163 unsigned len, unsigned copied, 164 struct page *page); 165 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry, 166 struct inode *inode); 167 extern int ext4_try_create_inline_dir(handle_t *handle, 168 struct inode *parent, 169 struct inode *inode); 170 extern int ext4_read_inline_dir(struct file *filp, 171 void *dirent, filldir_t filldir, 172 int *has_inline_data); 173 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir, 174 const struct qstr *d_name, 175 struct ext4_dir_entry_2 **res_dir, 176 int *has_inline_data); 177 extern int ext4_delete_inline_entry(handle_t *handle, 178 struct inode *dir, 179 struct ext4_dir_entry_2 *de_del, 180 struct buffer_head *bh, 181 int *has_inline_data); 182 extern int empty_inline_dir(struct inode *dir, int *has_inline_data); 183 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode, 184 struct ext4_dir_entry_2 **parent_de, 185 int *retval); 186 extern int ext4_inline_data_fiemap(struct inode *inode, 187 struct fiemap_extent_info *fieinfo, 188 int *has_inline); 189 extern int ext4_try_to_evict_inline_data(handle_t *handle, 190 struct inode *inode, 191 int needed); 192 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline); 193 194 extern int ext4_convert_inline_data(struct inode *inode); 195 196 #ifdef CONFIG_EXT4_FS_SECURITY 197 extern int ext4_init_security(handle_t *handle, struct inode *inode, 198 struct inode *dir, const struct qstr *qstr); 199 #else 200 static inline int ext4_init_security(handle_t *handle, struct inode *inode, 201 struct inode *dir, const struct qstr *qstr) 202 { 203 return 0; 204 } 205 #endif 206