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
15 static size_t
ext4_xattr_user_list(struct dentry * dentry,char * list,size_t list_size,const char * name,size_t name_len,int type)16 ext4_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
33 static int
ext4_xattr_user_get(struct dentry * dentry,const char * name,void * buffer,size_t size,int type)34 ext4_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
45 static int
ext4_xattr_user_set(struct dentry * dentry,const char * name,const void * value,size_t size,int flags,int type)46 ext4_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
57 const 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