LXR linux/fs/ext3/xattr.h

   1/*
   2  File: fs/ext3/xattr.h
   3
   4  On-disk format of extended attributes for the ext3 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 EXT3_XATTR_MAGIC                0xEA020000
  13
  14/* Maximum number of references to one attribute block */
  15#define EXT3_XATTR_REFCOUNT_MAX         1024
  16
  17/* Name indexes */
  18#define EXT3_XATTR_INDEX_USER                   1
  19#define EXT3_XATTR_INDEX_POSIX_ACL_ACCESS       2
  20#define EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT      3
  21#define EXT3_XATTR_INDEX_TRUSTED                4
  22#define EXT3_XATTR_INDEX_LUSTRE                 5
  23#define EXT3_XATTR_INDEX_SECURITY               6
  24
  25struct ext3_xattr_header {
  26        __le32  h_magic;        /* magic number for identification */
  27        __le32  h_refcount;     /* reference count */
  28        __le32  h_blocks;       /* number of disk blocks used */
  29        __le32  h_hash;         /* hash value of all attributes */
  30        __u32   h_reserved[4];  /* zero right now */
  31};
  32
  33struct ext3_xattr_ibody_header {
  34        __le32  h_magic;        /* magic number for identification */
  35};
  36
  37struct ext3_xattr_entry {
  38        __u8    e_name_len;     /* length of name */
  39        __u8    e_name_index;   /* attribute name index */
  40        __le16  e_value_offs;   /* offset in disk block of value */
  41        __le32  e_value_block;  /* disk block attribute is stored on (n/i) */
  42        __le32  e_value_size;   /* size of attribute value */
  43        __le32  e_hash;         /* hash value of name and value */
  44        char    e_name[0];      /* attribute name */
  45};
  46
  47#define EXT3_XATTR_PAD_BITS             2
  48#define EXT3_XATTR_PAD          (1<<EXT3_XATTR_PAD_BITS)
  49#define EXT3_XATTR_ROUND                (EXT3_XATTR_PAD-1)
  50#define EXT3_XATTR_LEN(name_len) \
  51        (((name_len) + EXT3_XATTR_ROUND + \
  52        sizeof(struct ext3_xattr_entry)) & ~EXT3_XATTR_ROUND)
  53#define EXT3_XATTR_NEXT(entry) \
  54        ( (struct ext3_xattr_entry *)( \
  55          (char *)(entry) + EXT3_XATTR_LEN((entry)->e_name_len)) )
  56#define EXT3_XATTR_SIZE(size) \
  57        (((size) + EXT3_XATTR_ROUND) & ~EXT3_XATTR_ROUND)
  58
  59# ifdef CONFIG_EXT3_FS_XATTR
  60
  61extern const struct xattr_handler ext3_xattr_user_handler;
  62extern const struct xattr_handler ext3_xattr_trusted_handler;
  63extern const struct xattr_handler ext3_xattr_security_handler;
  64
  65extern ssize_t ext3_listxattr(struct dentry *, char *, size_t);
  66
  67extern int ext3_xattr_get(struct inode *, int, const char *, void *, size_t);
  68extern int ext3_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
  69extern int ext3_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
  70
  71extern void ext3_xattr_delete_inode(handle_t *, struct inode *);
  72extern void ext3_xattr_put_super(struct super_block *);
  73
  74extern int init_ext3_xattr(void);
  75extern void exit_ext3_xattr(void);
  76
  77extern const struct xattr_handler *ext3_xattr_handlers[];
  78
  79# else  /* CONFIG_EXT3_FS_XATTR */
  80
  81static inline int
  82ext3_xattr_get(struct inode *inode, int name_index, const char *name,
  83               void *buffer, size_t size, int flags)
  84{
  85        return -EOPNOTSUPP;
  86}
  87
  88static inline int
  89ext3_xattr_set(struct inode *inode, int name_index, const char *name,
  90               const void *value, size_t size, int flags)
  91{
  92        return -EOPNOTSUPP;
  93}
  94
  95static inline int
  96ext3_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
  97               const char *name, const void *value, size_t size, int flags)
  98{
  99        return -EOPNOTSUPP;
 100}
 101
 102static inline void
 103ext3_xattr_delete_inode(handle_t *handle, struct inode *inode)
 104{
 105}
 106
 107static inline void
 108ext3_xattr_put_super(struct super_block *sb)
 109{
 110}
 111
 112static inline int
 113init_ext3_xattr(void)
 114{
 115        return 0;
 116}
 117
 118static inline void
 119exit_ext3_xattr(void)
 120{
 121}
 122
 123#define ext3_xattr_handlers     NULL
 124
 125# endif  /* CONFIG_EXT3_FS_XATTR */
 126
 127#ifdef CONFIG_EXT3_FS_SECURITY
 128extern int ext3_init_security(handle_t *handle, struct inode *inode,
 129                              struct inode *dir, const struct qstr *qstr);
 130#else
 131static inline int ext3_init_security(handle_t *handle, struct inode *inode,
 132                                     struct inode *dir, const struct qstr *qstr)
 133{
 134        return 0;
 135}
 136#endif
 137