1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 File: linux/posix_acl_xattr.h
4
5 Extended attribute system call representation of Access Control Lists.
6
7 Copyright (C) 2000 by Andreas Gruenbacher <a.gruenbacher@computer.org>
8 Copyright (C) 2002 SGI - Silicon Graphics, Inc <linux-xfs@oss.sgi.com>
9 */
10 #ifndef _POSIX_ACL_XATTR_H
11 #define _POSIX_ACL_XATTR_H
12
13 #include <uapi/linux/xattr.h>
14 #include <uapi/linux/posix_acl_xattr.h>
15 #include <linux/posix_acl.h>
16
17 static inline size_t
posix_acl_xattr_size(int count)18 posix_acl_xattr_size(int count)
19 {
20 return (sizeof(struct posix_acl_xattr_header) +
21 (count * sizeof(struct posix_acl_xattr_entry)));
22 }
23
24 static inline int
posix_acl_xattr_count(size_t size)25 posix_acl_xattr_count(size_t size)
26 {
27 if (size < sizeof(struct posix_acl_xattr_header))
28 return -1;
29 size -= sizeof(struct posix_acl_xattr_header);
30 if (size % sizeof(struct posix_acl_xattr_entry))
31 return -1;
32 return size / sizeof(struct posix_acl_xattr_entry);
33 }
34
35 #ifdef CONFIG_FS_POSIX_ACL
36 void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
37 struct inode *inode,
38 void *value, size_t size);
39 void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
40 struct inode *inode,
41 void *value, size_t size);
42 #else
posix_acl_fix_xattr_from_user(struct user_namespace * mnt_userns,struct inode * inode,void * value,size_t size)43 static inline void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
44 struct inode *inode,
45 void *value, size_t size)
46 {
47 }
posix_acl_fix_xattr_to_user(struct user_namespace * mnt_userns,struct inode * inode,void * value,size_t size)48 static inline void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
49 struct inode *inode,
50 void *value, size_t size)
51 {
52 }
53 #endif
54
55 struct posix_acl *posix_acl_from_xattr(struct user_namespace *user_ns,
56 const void *value, size_t size);
57 int posix_acl_to_xattr(struct user_namespace *user_ns,
58 const struct posix_acl *acl, void *buffer, size_t size);
59
60 extern const struct xattr_handler posix_acl_access_xattr_handler;
61 extern const struct xattr_handler posix_acl_default_xattr_handler;
62
63 #endif /* _POSIX_ACL_XATTR_H */
64