xref: /openbmc/linux/fs/ext4/xattr_user.c (revision 98e9cb57)
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 
14 static size_t
15 ext4_xattr_user_list(const struct xattr_handler *handler,
16 		     struct dentry *dentry, char *list, size_t list_size,
17 		     const char *name, size_t name_len)
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 
33 static int
34 ext4_xattr_user_get(const struct xattr_handler *handler,
35 		    struct dentry *dentry, const char *name,
36 		    void *buffer, size_t size)
37 {
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 
44 static int
45 ext4_xattr_user_set(const struct xattr_handler *handler,
46 		    struct dentry *dentry, const char *name,
47 		    const void *value, size_t size, int flags)
48 {
49 	if (!test_opt(dentry->d_sb, XATTR_USER))
50 		return -EOPNOTSUPP;
51 	return ext4_xattr_set(d_inode(dentry), EXT4_XATTR_INDEX_USER,
52 			      name, value, size, flags);
53 }
54 
55 const struct xattr_handler ext4_xattr_user_handler = {
56 	.prefix	= XATTR_USER_PREFIX,
57 	.list	= ext4_xattr_user_list,
58 	.get	= ext4_xattr_user_get,
59 	.set	= ext4_xattr_user_set,
60 };
61