xattr.h 4.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158
  1. /*
  2. File: fs/ext4/xattr.h
  3. On-disk format of extended attributes for the ext4 filesystem.
  4. (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
  5. */
  6. #include <linux/xattr.h>
  7. /* Magic value in attribute blocks */
  8. #define EXT4_XATTR_MAGIC 0xEA020000
  9. /* Maximum number of references to one attribute block */
  10. #define EXT4_XATTR_REFCOUNT_MAX 1024
  11. /* Name indexes */
  12. #define EXT4_XATTR_INDEX_USER 1
  13. #define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2
  14. #define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3
  15. #define EXT4_XATTR_INDEX_TRUSTED 4
  16. #define EXT4_XATTR_INDEX_LUSTRE 5
  17. #define EXT4_XATTR_INDEX_SECURITY 6
  18. struct ext4_xattr_header {
  19. __le32 h_magic; /* magic number for identification */
  20. __le32 h_refcount; /* reference count */
  21. __le32 h_blocks; /* number of disk blocks used */
  22. __le32 h_hash; /* hash value of all attributes */
  23. __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */
  24. /* id = inum if refcount=1, blknum otherwise */
  25. __u32 h_reserved[3]; /* zero right now */
  26. };
  27. struct ext4_xattr_ibody_header {
  28. __le32 h_magic; /* magic number for identification */
  29. };
  30. struct ext4_xattr_entry {
  31. __u8 e_name_len; /* length of name */
  32. __u8 e_name_index; /* attribute name index */
  33. __le16 e_value_offs; /* offset in disk block of value */
  34. __le32 e_value_block; /* disk block attribute is stored on (n/i) */
  35. __le32 e_value_size; /* size of attribute value */
  36. __le32 e_hash; /* hash value of name and value */
  37. char e_name[0]; /* attribute name */
  38. };
  39. #define EXT4_XATTR_PAD_BITS 2
  40. #define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
  41. #define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
  42. #define EXT4_XATTR_LEN(name_len) \
  43. (((name_len) + EXT4_XATTR_ROUND + \
  44. sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
  45. #define EXT4_XATTR_NEXT(entry) \
  46. ((struct ext4_xattr_entry *)( \
  47. (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
  48. #define EXT4_XATTR_SIZE(size) \
  49. (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
  50. #define IHDR(inode, raw_inode) \
  51. ((struct ext4_xattr_ibody_header *) \
  52. ((void *)raw_inode + \
  53. EXT4_GOOD_OLD_INODE_SIZE + \
  54. EXT4_I(inode)->i_extra_isize))
  55. #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
  56. # ifdef CONFIG_EXT4_FS_XATTR
  57. extern const struct xattr_handler ext4_xattr_user_handler;
  58. extern const struct xattr_handler ext4_xattr_trusted_handler;
  59. extern const struct xattr_handler ext4_xattr_acl_access_handler;
  60. extern const struct xattr_handler ext4_xattr_acl_default_handler;
  61. extern const struct xattr_handler ext4_xattr_security_handler;
  62. extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
  63. extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
  64. extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
  65. extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
  66. extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
  67. extern void ext4_xattr_put_super(struct super_block *);
  68. extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
  69. struct ext4_inode *raw_inode, handle_t *handle);
  70. extern int __init ext4_init_xattr(void);
  71. extern void ext4_exit_xattr(void);
  72. extern const struct xattr_handler *ext4_xattr_handlers[];
  73. # else /* CONFIG_EXT4_FS_XATTR */
  74. static inline int
  75. ext4_xattr_get(struct inode *inode, int name_index, const char *name,
  76. void *buffer, size_t size, int flags)
  77. {
  78. return -EOPNOTSUPP;
  79. }
  80. static inline int
  81. ext4_xattr_set(struct inode *inode, int name_index, const char *name,
  82. const void *value, size_t size, int flags)
  83. {
  84. return -EOPNOTSUPP;
  85. }
  86. static inline int
  87. ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
  88. const char *name, const void *value, size_t size, int flags)
  89. {
  90. return -EOPNOTSUPP;
  91. }
  92. static inline void
  93. ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
  94. {
  95. }
  96. static inline void
  97. ext4_xattr_put_super(struct super_block *sb)
  98. {
  99. }
  100. static __init inline int
  101. ext4_init_xattr(void)
  102. {
  103. return 0;
  104. }
  105. static inline void
  106. ext4_exit_xattr(void)
  107. {
  108. }
  109. static inline int
  110. ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
  111. struct ext4_inode *raw_inode, handle_t *handle)
  112. {
  113. return -EOPNOTSUPP;
  114. }
  115. #define ext4_xattr_handlers NULL
  116. # endif /* CONFIG_EXT4_FS_XATTR */
  117. #ifdef CONFIG_EXT4_FS_SECURITY
  118. extern int ext4_init_security(handle_t *handle, struct inode *inode,
  119. struct inode *dir, const struct qstr *qstr);
  120. #else
  121. static inline int ext4_init_security(handle_t *handle, struct inode *inode,
  122. struct inode *dir, const struct qstr *qstr)
  123. {
  124. return 0;
  125. }
  126. #endif