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/module.h>
   9#include <linux/string.h>
  10#include <linux/fs.h>
  11#include "ext4_jbd2.h"
  12#include "ext4.h"
  13#include "xattr.h"
  14
  15static size_t
  16ext4_xattr_user_list(struct dentry *dentry, char *list, size_t list_size,
  17                     const char *name, size_t name_len, int type)
  18{
  19        const size_t prefix_len = XATTR_USER_PREFIX_LEN;
  20        const size_t total_len = prefix_len + name_len + 1;
  21
  22        if (!test_opt(dentry->d_sb, XATTR_USER))
  23                return 0;
  24
  25        if (list && total_len <= list_size) {
  26                memcpy(list, XATTR_USER_PREFIX, prefix_len);
  27                memcpy(list+prefix_len, name, name_len);
  28                list[prefix_len + name_len] = '\0';
  29        }
  30        return total_len;
  31}
  32
  33static int
  34ext4_xattr_user_get(struct dentry *dentry, const char *name,
  35                    void *buffer, size_t size, int type)
  36{
  37        if (strcmp(name, "") == 0)
  38                return -EINVAL;
  39        if (!test_opt(dentry->d_sb, XATTR_USER))
  40                return -EOPNOTSUPP;
  41        return ext4_xattr_get(dentry->d_inode, EXT4_XATTR_INDEX_USER,
  42                              name, buffer, size);
  43}
  44
  45static int
  46ext4_xattr_user_set(struct dentry *dentry, const char *name,
  47                    const void *value, size_t size, int flags, int type)
  48{
  49        if (strcmp(name, "") == 0)
  50                return -EINVAL;
  51        if (!test_opt(dentry->d_sb, XATTR_USER))
  52                return -EOPNOTSUPP;
  53        return ext4_xattr_set(dentry->d_inode, EXT4_XATTR_INDEX_USER,
  54                              name, value, size, flags);
  55}
  56
  57const struct xattr_handler ext4_xattr_user_handler = {
  58        .prefix = XATTR_USER_PREFIX,
  59        .list   = ext4_xattr_user_list,
  60        .get    = ext4_xattr_user_get,
  61        .set    = ext4_xattr_user_set,
  62};
  63