LXR linux/fs/ext4/xattr

   1/*
   2 * linux/fs/ext4/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/string.h>
   9#include <linux/fs.h>
  10#include "ext4_jbd2.h"
  11#include "ext4.h"
  12#include "xattr.h"
  13
  14static size_t
  15ext4_xattr_user_list(struct dentry *dentry, char *list, size_t list_size,
  16                     const char *name, size_t name_len, int type)
  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(dentry->d_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
  32static int
  33ext4_xattr_user_get(struct dentry *dentry, const char *name,
  34                    void *buffer, size_t size, int type)
  35{
  36        if (strcmp(name, "") == 0)
  37                return -EINVAL;
  38        if (!test_opt(dentry->d_sb, XATTR_USER))
  39                return -EOPNOTSUPP;
  40        return ext4_xattr_get(dentry->d_inode, EXT4_XATTR_INDEX_USER,
  41                              name, buffer, size);
  42}
  43
  44static int
  45ext4_xattr_user_set(struct dentry *dentry, const char *name,
  46                    const void *value, size_t size, int flags, int type)
  47{
  48        if (strcmp(name, "") == 0)
  49                return -EINVAL;
  50        if (!test_opt(dentry->d_sb, XATTR_USER))
  51                return -EOPNOTSUPP;
  52        return ext4_xattr_set(dentry->d_inode, EXT4_XATTR_INDEX_USER,
  53                              name, value, size, flags);
  54}
  55
  56const struct xattr_handler ext4_xattr_user_handler = {
  57        .prefix = XATTR_USER_PREFIX,
  58        .list   = ext4_xattr_user_list,
  59        .get    = ext4_xattr_user_get,
  60        .set    = ext4_xattr_user_set,
  61};
  62