xref: /linux/fs/ext2/acl.h (revision 005438a8eef063495ac059d128eea71b58de50e5)
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_set_acl(struct inode *inode, struct posix_acl *acl, int type);
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 ext2_init_acl (struct inode *inode, struct inode *dir)
67  {
68  	return 0;
69  }
70  #endif
71  
72