xref: /linux/fs/ext2/acl.h (revision 5051c94bb3998ff24bf07ae3b72dca30f85962f8)
1 /*
2   File: fs/ext2/acl.h
3 
4   (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
5 */
6 
7 #include <linux/posix_acl_xattr.h>
8 
9 #define EXT2_ACL_VERSION	0x0001
10 
11 typedef struct {
12 	__le16		e_tag;
13 	__le16		e_perm;
14 	__le32		e_id;
15 } ext2_acl_entry;
16 
17 typedef struct {
18 	__le16		e_tag;
19 	__le16		e_perm;
20 } ext2_acl_entry_short;
21 
22 typedef struct {
23 	__le32		a_version;
24 } ext2_acl_header;
25 
26 static inline size_t ext2_acl_size(int count)
27 {
28 	if (count <= 4) {
29 		return sizeof(ext2_acl_header) +
30 		       count * sizeof(ext2_acl_entry_short);
31 	} else {
32 		return sizeof(ext2_acl_header) +
33 		       4 * sizeof(ext2_acl_entry_short) +
34 		       (count - 4) * sizeof(ext2_acl_entry);
35 	}
36 }
37 
38 static inline int ext2_acl_count(size_t size)
39 {
40 	ssize_t s;
41 	size -= sizeof(ext2_acl_header);
42 	s = size - 4 * sizeof(ext2_acl_entry_short);
43 	if (s < 0) {
44 		if (size % sizeof(ext2_acl_entry_short))
45 			return -1;
46 		return size / sizeof(ext2_acl_entry_short);
47 	} else {
48 		if (s % sizeof(ext2_acl_entry))
49 			return -1;
50 		return s / sizeof(ext2_acl_entry) + 4;
51 	}
52 }
53 
54 #ifdef CONFIG_EXT2_FS_POSIX_ACL
55 
56 /* acl.c */
57 extern struct posix_acl *ext2_get_acl(struct inode *inode, int type);
58 extern int ext2_acl_chmod (struct inode *);
59 extern int ext2_init_acl (struct inode *, struct inode *);
60 
61 #else
62 #include <linux/sched.h>
63 #define ext2_get_acl	NULL
64 #define ext2_set_acl	NULL
65 
66 static inline int
67 ext2_acl_chmod (struct inode *inode)
68 {
69 	return 0;
70 }
71 
72 static inline int ext2_init_acl (struct inode *inode, struct inode *dir)
73 {
74 	return 0;
75 }
76 #endif
77 
78