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(d_inode(dentry), 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(d_inode(dentry), 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