GNU Linux-libre 6.1.86-gnu
[releases.git] / fs / ext2 / acl.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3   File: fs/ext2/acl.h
4
5   (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
6 */
7
8 #include <linux/posix_acl_xattr.h>
9
10 #define EXT2_ACL_VERSION        0x0001
11
12 typedef struct {
13         __le16          e_tag;
14         __le16          e_perm;
15         __le32          e_id;
16 } ext2_acl_entry;
17
18 typedef struct {
19         __le16          e_tag;
20         __le16          e_perm;
21 } ext2_acl_entry_short;
22
23 typedef struct {
24         __le32          a_version;
25 } ext2_acl_header;
26
27 static inline size_t ext2_acl_size(int count)
28 {
29         if (count <= 4) {
30                 return sizeof(ext2_acl_header) +
31                        count * sizeof(ext2_acl_entry_short);
32         } else {
33                 return sizeof(ext2_acl_header) +
34                        4 * sizeof(ext2_acl_entry_short) +
35                        (count - 4) * sizeof(ext2_acl_entry);
36         }
37 }
38
39 static inline int ext2_acl_count(size_t size)
40 {
41         ssize_t s;
42         size -= sizeof(ext2_acl_header);
43         s = size - 4 * sizeof(ext2_acl_entry_short);
44         if (s < 0) {
45                 if (size % sizeof(ext2_acl_entry_short))
46                         return -1;
47                 return size / sizeof(ext2_acl_entry_short);
48         } else {
49                 if (s % sizeof(ext2_acl_entry))
50                         return -1;
51                 return s / sizeof(ext2_acl_entry) + 4;
52         }
53 }
54
55 #ifdef CONFIG_EXT2_FS_POSIX_ACL
56
57 /* acl.c */
58 extern struct posix_acl *ext2_get_acl(struct inode *inode, int type, bool rcu);
59 extern int ext2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
60                         struct posix_acl *acl, int type);
61 extern int ext2_init_acl (struct inode *, struct inode *);
62
63 #else
64 #include <linux/sched.h>
65 #define ext2_get_acl    NULL
66 #define ext2_set_acl    NULL
67
68 static inline int ext2_init_acl (struct inode *inode, struct inode *dir)
69 {
70         return 0;
71 }
72 #endif
73