xattr.h 4.5 KB

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  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. #define EXT4_XATTR_INDEX_SYSTEM 7
  19. struct ext4_xattr_header {
  20. __le32 h_magic; /* magic number for identification */
  21. __le32 h_refcount; /* reference count */
  22. __le32 h_blocks; /* number of disk blocks used */
  23. __le32 h_hash; /* hash value of all attributes */
  24. __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */
  25. /* id = inum if refcount=1, blknum otherwise */
  26. __u32 h_reserved[3]; /* zero right now */
  27. };
  28. struct ext4_xattr_ibody_header {
  29. __le32 h_magic; /* magic number for identification */
  30. };
  31. struct ext4_xattr_entry {
  32. __u8 e_name_len; /* length of name */
  33. __u8 e_name_index; /* attribute name index */
  34. __le16 e_value_offs; /* offset in disk block of value */
  35. __le32 e_value_block; /* disk block attribute is stored on (n/i) */
  36. __le32 e_value_size; /* size of attribute value */
  37. __le32 e_hash; /* hash value of name and value */
  38. char e_name[0]; /* attribute name */
  39. };
  40. #define EXT4_XATTR_PAD_BITS 2
  41. #define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
  42. #define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
  43. #define EXT4_XATTR_LEN(name_len) \
  44. (((name_len) + EXT4_XATTR_ROUND + \
  45. sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
  46. #define EXT4_XATTR_NEXT(entry) \
  47. ((struct ext4_xattr_entry *)( \
  48. (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
  49. #define EXT4_XATTR_SIZE(size) \
  50. (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
  51. #define IHDR(inode, raw_inode) \
  52. ((struct ext4_xattr_ibody_header *) \
  53. ((void *)raw_inode + \
  54. EXT4_GOOD_OLD_INODE_SIZE + \
  55. EXT4_I(inode)->i_extra_isize))
  56. #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
  57. # ifdef CONFIG_EXT4_FS_XATTR
  58. extern const struct xattr_handler ext4_xattr_user_handler;
  59. extern const struct xattr_handler ext4_xattr_trusted_handler;
  60. extern const struct xattr_handler ext4_xattr_acl_access_handler;
  61. extern const struct xattr_handler ext4_xattr_acl_default_handler;
  62. extern const struct xattr_handler ext4_xattr_security_handler;
  63. extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
  64. extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
  65. extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
  66. extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
  67. extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
  68. extern void ext4_xattr_put_super(struct super_block *);
  69. extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
  70. struct ext4_inode *raw_inode, handle_t *handle);
  71. extern int __init ext4_init_xattr(void);
  72. extern void ext4_exit_xattr(void);
  73. extern const struct xattr_handler *ext4_xattr_handlers[];
  74. # else /* CONFIG_EXT4_FS_XATTR */
  75. static inline int
  76. ext4_xattr_get(struct inode *inode, int name_index, const char *name,
  77. void *buffer, size_t size, int flags)
  78. {
  79. return -EOPNOTSUPP;
  80. }
  81. static inline int
  82. ext4_xattr_set(struct inode *inode, int name_index, const char *name,
  83. const void *value, size_t size, int flags)
  84. {
  85. return -EOPNOTSUPP;
  86. }
  87. static inline int
  88. ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
  89. const char *name, const void *value, size_t size, int flags)
  90. {
  91. return -EOPNOTSUPP;
  92. }
  93. static inline void
  94. ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
  95. {
  96. }
  97. static inline void
  98. ext4_xattr_put_super(struct super_block *sb)
  99. {
  100. }
  101. static __init inline int
  102. ext4_init_xattr(void)
  103. {
  104. return 0;
  105. }
  106. static inline void
  107. ext4_exit_xattr(void)
  108. {
  109. }
  110. static inline int
  111. ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
  112. struct ext4_inode *raw_inode, handle_t *handle)
  113. {
  114. return -EOPNOTSUPP;
  115. }
  116. #define ext4_xattr_handlers NULL
  117. # endif /* CONFIG_EXT4_FS_XATTR */
  118. #ifdef CONFIG_EXT4_FS_SECURITY
  119. extern int ext4_init_security(handle_t *handle, struct inode *inode,
  120. struct inode *dir, const struct qstr *qstr);
  121. #else
  122. static inline int ext4_init_security(handle_t *handle, struct inode *inode,
  123. struct inode *dir, const struct qstr *qstr)
  124. {
  125. return 0;
  126. }
  127. #endif