xref: /openbmc/linux/fs/erofs/xattr.h (revision cf21eb6a)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2017-2018 HUAWEI, Inc.
4  *             https://www.huawei.com/
5  */
6 #ifndef __EROFS_XATTR_H
7 #define __EROFS_XATTR_H
8 
9 #include "internal.h"
10 #include <linux/posix_acl_xattr.h>
11 #include <linux/xattr.h>
12 
13 /* Attribute not found */
14 #define ENOATTR         ENODATA
15 
16 #ifdef CONFIG_EROFS_FS_XATTR
17 extern const struct xattr_handler erofs_xattr_user_handler;
18 extern const struct xattr_handler erofs_xattr_trusted_handler;
19 extern const struct xattr_handler erofs_xattr_security_handler;
20 
21 static inline const char *erofs_xattr_prefix(unsigned int idx,
22 					     struct dentry *dentry)
23 {
24 	const struct xattr_handler *handler = NULL;
25 
26 	static const struct xattr_handler *xattr_handler_map[] = {
27 		[EROFS_XATTR_INDEX_USER] = &erofs_xattr_user_handler,
28 #ifdef CONFIG_EROFS_FS_POSIX_ACL
29 		[EROFS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
30 		[EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
31 #endif
32 		[EROFS_XATTR_INDEX_TRUSTED] = &erofs_xattr_trusted_handler,
33 #ifdef CONFIG_EROFS_FS_SECURITY
34 		[EROFS_XATTR_INDEX_SECURITY] = &erofs_xattr_security_handler,
35 #endif
36 	};
37 
38 	if (idx && idx < ARRAY_SIZE(xattr_handler_map))
39 		handler = xattr_handler_map[idx];
40 
41 	if (!xattr_handler_can_list(handler, dentry))
42 		return NULL;
43 
44 	return xattr_prefix(handler);
45 }
46 
47 extern const struct xattr_handler *erofs_xattr_handlers[];
48 
49 int erofs_xattr_prefixes_init(struct super_block *sb);
50 void erofs_xattr_prefixes_cleanup(struct super_block *sb);
51 int erofs_getxattr(struct inode *, int, const char *, void *, size_t);
52 ssize_t erofs_listxattr(struct dentry *, char *, size_t);
53 #else
54 static inline int erofs_xattr_prefixes_init(struct super_block *sb) { return 0; }
55 static inline void erofs_xattr_prefixes_cleanup(struct super_block *sb) {}
56 static inline int erofs_getxattr(struct inode *inode, int index,
57 				 const char *name, void *buffer,
58 				 size_t buffer_size)
59 {
60 	return -EOPNOTSUPP;
61 }
62 
63 #define erofs_listxattr (NULL)
64 #define erofs_xattr_handlers (NULL)
65 #endif	/* !CONFIG_EROFS_FS_XATTR */
66 
67 #ifdef CONFIG_EROFS_FS_POSIX_ACL
68 struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu);
69 #else
70 #define erofs_get_acl	(NULL)
71 #endif
72 
73 #endif
74