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 # else  /* CONFIG_EXT4_FS_XATTR */
 188
 189 static inline int
 190 ext4_xattr_get(struct inode *inode, int name_index, const char *name,
 191                void *buffer, size_t size, int flags)
 192 {
 193         return -EOPNOTSUPP;
 194 }
 195
 196 static inline int
 197 ext4_xattr_set(struct inode *inode, int name_index, const char *name,
 198                const void *value, size_t size, int flags)
 199 {
 200         return -EOPNOTSUPP;
 201 }
 202
 203 static inline int
 204 ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
 205                const char *name, const void *value, size_t size, int flags)
 206 {
 207         return -EOPNOTSUPP;
 208 }
 209
 210 static inline void
 211 ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
 212 {
 213 }
 214
 215 static inline void
 216 ext4_xattr_put_super(struct super_block *sb)
 217 {
 218 }
 219
 220 static __init inline int
 221 ext4_init_xattr(void)
 222 {
 223         return 0;
 224 }
 225
 226 static inline void
 227 ext4_exit_xattr(void)
 228 {
 229 }
 230
 231 static inline int
 232 ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
 233                             struct ext4_inode *raw_inode, handle_t *handle)
 234 {
 235         return -EOPNOTSUPP;
 236 }
 237
 238 #define ext4_xattr_handlers     NULL
 239
 240 static inline int
 241 ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
 242                       struct ext4_xattr_ibody_find *is)
 243 {
 244         return -EOPNOTSUPP;
 245 }
 246
 247 static inline int
 248 ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
 249                      struct ext4_xattr_info *i,
 250                      struct ext4_xattr_ibody_find *is)
 251 {
 252         return -EOPNOTSUPP;
 253 }
 254
 255 static inline int
 256 ext4_xattr_ibody_get(struct inode *inode, int name_index,
 257                      const char *name,
 258                      void *buffer, size_t buffer_size)
 259 {
 260         return -EOPNOTSUPP;
 261 }
 262
 263 static inline int ext4_find_inline_data_nolock(struct inode *inode)
 264 {
 265         return 0;
 266 }
 267
 268 static inline int ext4_has_inline_data(struct inode *inode)
 269 {
 270         return 0;
 271 }
 272
 273 static inline int ext4_get_inline_size(struct inode *inode)
 274 {
 275         return 0;
 276 }
 277
 278 static inline int ext4_get_max_inline_size(struct inode *inode)
 279 {
 280         return 0;
 281 }
 282
 283 static inline void ext4_write_inline_data(struct inode *inode,
 284                                           struct ext4_iloc *iloc,
 285                                           void *buffer, loff_t pos,
 286                                           unsigned int len)
 287 {
 288         return;
 289 }
 290
 291 static inline int ext4_init_inline_data(handle_t *handle,
 292                                         struct inode *inode,
 293                                         unsigned int len)
 294 {
 295         return 0;
 296 }
 297
 298 static inline int ext4_destroy_inline_data(handle_t *handle,
 299                                            struct inode *inode)
 300 {
 301         return 0;
 302 }
 303
 304 static inline int ext4_readpage_inline(struct inode *inode, struct page *page)
 305 {
 306         return 0;
 307 }
 308
 309 static inline int ext4_try_to_write_inline_data(struct address_space *mapping,
 310                                                 struct inode *inode,
 311                                                 loff_t pos, unsigned len,
 312                                                 unsigned flags,
 313                                                 struct page **pagep)
 314 {
 315         return 0;
 316 }
 317
 318 static inline int ext4_write_inline_data_end(struct inode *inode,
 319                                              loff_t pos, unsigned len,
 320                                              unsigned copied,
 321                                              struct page *page)
 322 {
 323         return 0;
 324 }
 325
 326 static inline struct buffer_head *
 327 ext4_journalled_write_inline_data(struct inode *inode,
 328                                   unsigned len,
 329                                   struct page *page)
 330 {
 331         return NULL;
 332 }
 333
 334 static inline int
 335 ext4_da_write_inline_data_begin(struct address_space *mapping,
 336                                 struct inode *inode,
 337                                 loff_t pos, unsigned len,
 338                                 unsigned flags,
 339                                 struct page **pagep,
 340                                 void **fsdata)
 341 {
 342         return 0;
 343 }
 344
 345 static inline int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
 346                                                 unsigned len, unsigned copied,
 347                                                 struct page *page)
 348 {
 349         return 0;
 350 }
 351
 352 static inline int ext4_try_add_inline_entry(handle_t *handle,
 353                                             struct dentry *dentry,
 354                                             struct inode *inode)
 355 {
 356         return 0;
 357 }
 358
 359 static inline int ext4_try_create_inline_dir(handle_t *handle,
 360                                              struct inode *parent,
 361                                              struct inode *inode)
 362 {
 363         return 0;
 364 }
 365 static inline int ext4_read_inline_dir(struct file *filp,
 366                                        void *dirent, filldir_t filldir,
 367                                        int *has_inline_data)
 368 {
 369         return 0;
 370 }
 371
 372 static inline struct buffer_head *
 373 ext4_find_inline_entry(struct inode *dir,
 374                        const struct qstr *d_name,
 375                        struct ext4_dir_entry_2 **res_dir,
 376                        int *has_inline_data)
 377 {
 378         return NULL;
 379 }
 380 static inline int ext4_delete_inline_entry(handle_t *handle,
 381                                            struct inode *dir,
 382                                            struct ext4_dir_entry_2 *de_del,
 383                                            struct buffer_head *bh,
 384                                            int *has_inline_data)
 385 {
 386         return 0;
 387 }
 388
 389 static inline int empty_inline_dir(struct inode *dir, int *has_inline_data)
 390 {
 391         return 0;
 392 }
 393
 394 static inline struct buffer_head *
 395 ext4_get_first_inline_block(struct inode *inode,
 396                             struct ext4_dir_entry_2 **parent_de,
 397                             int *retval)
 398 {
 399         return NULL;
 400 }
 401 # endif  /* CONFIG_EXT4_FS_XATTR */
 402
 403 #ifdef CONFIG_EXT4_FS_SECURITY
 404 extern int ext4_init_security(handle_t *handle, struct inode *inode,
 405                               struct inode *dir, const struct qstr *qstr);
 406 #else
 407 static inline int ext4_init_security(handle_t *handle, struct inode *inode,
 408                                      struct inode *dir, const struct qstr *qstr)
 409 {
 410         return 0;
 411 }
 412 #endif