fs/ext2/xattr_user.c

   1 /*
   2  * linux/fs/ext2/xattr_user.c
   3  * Handler for extended user attributes.
   4  *
   5  * Copyright (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
   6  */
   7
   8 #include <linux/init.h>
   9 #include <linux/module.h>
  10 #include <linux/string.h>
  11 #include "ext2.h"
  12 #include "xattr.h"
  13
  14 static size_t
  15 ext2_xattr_user_list(struct inode *inode, char *list, size_t list_size,
  16                      const char *name, size_t name_len)
  17 {
  18         const size_t prefix_len = XATTR_USER_PREFIX_LEN;
  19         const size_t total_len = prefix_len + name_len + 1;
  20
  21         if (!test_opt(inode->i_sb, XATTR_USER))
  22                 return 0;
  23
  24         if (list && total_len <= list_size) {
  25                 memcpy(list, XATTR_USER_PREFIX, prefix_len);
  26                 memcpy(list+prefix_len, name, name_len);
  27                 list[prefix_len + name_len] = '\0';
  28         }
  29         return total_len;
  30 }
  31
  32 static int
  33 ext2_xattr_user_get(struct inode *inode, const char *name,
  34                     void *buffer, size_t size)
  35 {
  36         if (strcmp(name, "") == 0)
  37                 return -EINVAL;
  38         if (!test_opt(inode->i_sb, XATTR_USER))
  39                 return -EOPNOTSUPP;
  40         return ext2_xattr_get(inode, EXT2_XATTR_INDEX_USER, name, buffer, size);
  41 }
  42
  43 static int
  44 ext2_xattr_user_set(struct inode *inode, const char *name,
  45                     const void *value, size_t size, int flags)
  46 {
  47         if (strcmp(name, "") == 0)
  48                 return -EINVAL;
  49         if (!test_opt(inode->i_sb, XATTR_USER))
  50                 return -EOPNOTSUPP;
  51
  52         return ext2_xattr_set(inode, EXT2_XATTR_INDEX_USER, name,
  53                               value, size, flags);
  54 }
  55
  56 struct xattr_handler ext2_xattr_user_handler = {
  57         .prefix = XATTR_USER_PREFIX,
  58         .list   = ext2_xattr_user_list,
  59         .get    = ext2_xattr_user_get,
  60         .set    = ext2_xattr_user_set,
  61 };