fs/ext4/xattr.h

   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
  75 struct ext4_xattr_info {
  76         int name_index;
  77         const char *name;
  78         const void *value;
  79         size_t value_len;
  80 };
  81
  82 struct ext4_xattr_search {
  83         struct ext4_xattr_entry *first;
  84         void *base;
  85         void *end;
  86         struct ext4_xattr_entry *here;
  87         int not_found;
  88 };
  89
  90 struct ext4_xattr_ibody_find {
  91         struct ext4_xattr_search s;
  92         struct ext4_iloc iloc;
  93 };
  94
  95 # ifdef CONFIG_EXT4_FS_XATTR
  96
  97 extern const struct xattr_handler ext4_xattr_user_handler;
  98 extern const struct xattr_handler ext4_xattr_trusted_handler;
  99 extern const struct xattr_handler ext4_xattr_acl_access_handler;
 100 extern const struct xattr_handler ext4_xattr_acl_default_handler;
 101 extern const struct xattr_handler ext4_xattr_security_handler;
 102
 103 extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
 104
 105 extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
 106 extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
 107 extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
 108
 109 extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
 110 extern void ext4_xattr_put_super(struct super_block *);
 111
 112 extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
 113                             struct ext4_inode *raw_inode, handle_t *handle);
 114
 115 extern int __init ext4_init_xattr(void);
 116 extern void ext4_exit_xattr(void);
 117
 118 extern const struct xattr_handler *ext4_xattr_handlers[];
 119
 120 extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
 121                                  struct ext4_xattr_ibody_find *is);
 122 extern int ext4_xattr_ibody_get(struct inode *inode, int name_index,
 123                                 const char *name,
 124                                 void *buffer, size_t buffer_size);
 125 extern int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
 126                                 struct ext4_xattr_info *i,
 127                                 struct ext4_xattr_ibody_find *is);
 128
 129 extern int ext4_has_inline_data(struct inode *inode);
 130 extern int ext4_get_inline_size(struct inode *inode);
 131 extern int ext4_get_max_inline_size(struct inode *inode);
 132 extern int ext4_find_inline_data_nolock(struct inode *inode);
 133 extern void ext4_write_inline_data(struct inode *inode,
 134                                    struct ext4_iloc *iloc,
 135                                    void *buffer, loff_t pos,
 136                                    unsigned int len);
 137 extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
 138                                     unsigned int len);
 139 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
 140                                  unsigned int len);
 141 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
 142
 143 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
 144 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
 145                                          struct inode *inode,
 146                                          loff_t pos, unsigned len,
 147                                          unsigned flags,
 148                                          struct page **pagep);
 149 extern int ext4_write_inline_data_end(struct inode *inode,
 150                                       loff_t pos, unsigned len,
 151                                       unsigned copied,
 152                                       struct page *page);
 153 extern struct buffer_head *
 154 ext4_journalled_write_inline_data(struct inode *inode,
 155                                   unsigned len,
 156                                   struct page *page);
 157 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
 158                                            struct inode *inode,
 159                                            loff_t pos, unsigned len,
 160                                            unsigned flags,
 161                                            struct page **pagep,
 162                                            void **fsdata);
 163 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
 164                                          unsigned len, unsigned copied,
 165                                          struct page *page);
 166 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
 167                                      struct inode *inode);
 168 extern int ext4_try_create_inline_dir(handle_t *handle,
 169                                       struct inode *parent,
 170                                       struct inode *inode);
 171 extern int ext4_read_inline_dir(struct file *filp,
 172                                 void *dirent, filldir_t filldir,
 173                                 int *has_inline_data);
 174 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
 175                                         const struct qstr *d_name,
 176                                         struct ext4_dir_entry_2 **res_dir,
 177                                         int *has_inline_data);
 178 extern int ext4_delete_inline_entry(handle_t *handle,
 179                                     struct inode *dir,
 180                                     struct ext4_dir_entry_2 *de_del,
 181                                     struct buffer_head *bh,
 182                                     int *has_inline_data);
 183 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
 184 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
 185                                         struct ext4_dir_entry_2 **parent_de,
 186                                         int *retval);
 187 extern int ext4_inline_data_fiemap(struct inode *inode,
 188                                    struct fiemap_extent_info *fieinfo,
 189                                    int *has_inline);
 190 # else  /* CONFIG_EXT4_FS_XATTR */
 191
 192 static inline int
 193 ext4_xattr_get(struct inode *inode, int name_index, const char *name,
 194                void *buffer, size_t size, int flags)
 195 {
 196         return -EOPNOTSUPP;
 197 }
 198
 199 static inline int
 200 ext4_xattr_set(struct inode *inode, int name_index, const char *name,
 201                const void *value, size_t size, int flags)
 202 {
 203         return -EOPNOTSUPP;
 204 }
 205
 206 static inline int
 207 ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
 208                const char *name, const void *value, size_t size, int flags)
 209 {
 210         return -EOPNOTSUPP;
 211 }
 212
 213 static inline void
 214 ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
 215 {
 216 }
 217
 218 static inline void
 219 ext4_xattr_put_super(struct super_block *sb)
 220 {
 221 }
 222
 223 static __init inline int
 224 ext4_init_xattr(void)
 225 {
 226         return 0;
 227 }
 228
 229 static inline void
 230 ext4_exit_xattr(void)
 231 {
 232 }
 233
 234 static inline int
 235 ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
 236                             struct ext4_inode *raw_inode, handle_t *handle)
 237 {
 238         return -EOPNOTSUPP;
 239 }
 240
 241 #define ext4_xattr_handlers     NULL
 242
 243 static inline int
 244 ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
 245                       struct ext4_xattr_ibody_find *is)
 246 {
 247         return -EOPNOTSUPP;
 248 }
 249
 250 static inline int
 251 ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
 252                      struct ext4_xattr_info *i,
 253                      struct ext4_xattr_ibody_find *is)
 254 {
 255         return -EOPNOTSUPP;
 256 }
 257
 258 static inline int
 259 ext4_xattr_ibody_get(struct inode *inode, int name_index,
 260                      const char *name,
 261                      void *buffer, size_t buffer_size)
 262 {
 263         return -EOPNOTSUPP;
 264 }
 265
 266 static inline int ext4_find_inline_data_nolock(struct inode *inode)
 267 {
 268         return 0;
 269 }
 270
 271 static inline int ext4_has_inline_data(struct inode *inode)
 272 {
 273         return 0;
 274 }
 275
 276 static inline int ext4_get_inline_size(struct inode *inode)
 277 {
 278         return 0;
 279 }
 280
 281 static inline int ext4_get_max_inline_size(struct inode *inode)
 282 {
 283         return 0;
 284 }
 285
 286 static inline void ext4_write_inline_data(struct inode *inode,
 287                                           struct ext4_iloc *iloc,
 288                                           void *buffer, loff_t pos,
 289                                           unsigned int len)
 290 {
 291         return;
 292 }
 293
 294 static inline int ext4_init_inline_data(handle_t *handle,
 295                                         struct inode *inode,
 296                                         unsigned int len)
 297 {
 298         return 0;
 299 }
 300
 301 static inline int ext4_destroy_inline_data(handle_t *handle,
 302                                            struct inode *inode)
 303 {
 304         return 0;
 305 }
 306
 307 static inline int ext4_readpage_inline(struct inode *inode, struct page *page)
 308 {
 309         return 0;
 310 }
 311
 312 static inline int ext4_try_to_write_inline_data(struct address_space *mapping,
 313                                                 struct inode *inode,
 314                                                 loff_t pos, unsigned len,
 315                                                 unsigned flags,
 316                                                 struct page **pagep)
 317 {
 318         return 0;
 319 }
 320
 321 static inline int ext4_write_inline_data_end(struct inode *inode,
 322                                              loff_t pos, unsigned len,
 323                                              unsigned copied,
 324                                              struct page *page)
 325 {
 326         return 0;
 327 }
 328
 329 static inline struct buffer_head *
 330 ext4_journalled_write_inline_data(struct inode *inode,
 331                                   unsigned len,
 332                                   struct page *page)
 333 {
 334         return NULL;
 335 }
 336
 337 static inline int
 338 ext4_da_write_inline_data_begin(struct address_space *mapping,
 339                                 struct inode *inode,
 340                                 loff_t pos, unsigned len,
 341                                 unsigned flags,
 342                                 struct page **pagep,
 343                                 void **fsdata)
 344 {
 345         return 0;
 346 }
 347
 348 static inline int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
 349                                                 unsigned len, unsigned copied,
 350                                                 struct page *page)
 351 {
 352         return 0;
 353 }
 354
 355 static inline int ext4_try_add_inline_entry(handle_t *handle,
 356                                             struct dentry *dentry,
 357                                             struct inode *inode)
 358 {
 359         return 0;
 360 }
 361
 362 static inline int ext4_try_create_inline_dir(handle_t *handle,
 363                                              struct inode *parent,
 364                                              struct inode *inode)
 365 {
 366         return 0;
 367 }
 368 static inline int ext4_read_inline_dir(struct file *filp,
 369                                        void *dirent, filldir_t filldir,
 370                                        int *has_inline_data)
 371 {
 372         return 0;
 373 }
 374
 375 static inline struct buffer_head *
 376 ext4_find_inline_entry(struct inode *dir,
 377                        const struct qstr *d_name,
 378                        struct ext4_dir_entry_2 **res_dir,
 379                        int *has_inline_data)
 380 {
 381         return NULL;
 382 }
 383 static inline int ext4_delete_inline_entry(handle_t *handle,
 384                                            struct inode *dir,
 385                                            struct ext4_dir_entry_2 *de_del,
 386                                            struct buffer_head *bh,
 387                                            int *has_inline_data)
 388 {
 389         return 0;
 390 }
 391
 392 static inline int empty_inline_dir(struct inode *dir, int *has_inline_data)
 393 {
 394         return 0;
 395 }
 396
 397 static inline struct buffer_head *
 398 ext4_get_first_inline_block(struct inode *inode,
 399                             struct ext4_dir_entry_2 **parent_de,
 400                             int *retval)
 401 {
 402         return NULL;
 403 }
 404
 405 static inline int ext4_inline_data_fiemap(struct inode *inode,
 406                                           struct fiemap_extent_info *fieinfo,
 407                                           int *has_inline)
 408 {
 409         return 0;
 410 }
 411 # endif  /* CONFIG_EXT4_FS_XATTR */
 412
 413 #ifdef CONFIG_EXT4_FS_SECURITY
 414 extern int ext4_init_security(handle_t *handle, struct inode *inode,
 415                               struct inode *dir, const struct qstr *qstr);
 416 #else
 417 static inline int ext4_init_security(handle_t *handle, struct inode *inode,
 418                                      struct inode *dir, const struct qstr *qstr)
 419 {
 420         return 0;
 421 }
 422 #endif