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gerrit-public.fairphone.software / kernel / msm-4.9 / 26887793b64ae93342c1e2548595d4c6f7dce694 / . / include / linux / posix_acl.h
blob: 065a3652a3eaf92a8381db3f35e78f86e470a488 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/*
2 File: linux/posix_acl.h
3
4 (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org>
5*/
6
7
8#ifndef __LINUX_POSIX_ACL_H
9#define __LINUX_POSIX_ACL_H
10
11#include <linux/slab.h>
12
13#define ACL_UNDEFINED_ID (-1)
14
15/* a_type field in acl_user_posix_entry_t */
16#define ACL_TYPE_ACCESS (0x8000)
17#define ACL_TYPE_DEFAULT (0x4000)
18
19/* e_tag entry in struct posix_acl_entry */
20#define ACL_USER_OBJ (0x01)
21#define ACL_USER (0x02)
22#define ACL_GROUP_OBJ (0x04)
23#define ACL_GROUP (0x08)
24#define ACL_MASK (0x10)
25#define ACL_OTHER (0x20)
26
27/* permissions in the e_perm field */
28#define ACL_READ (0x04)
29#define ACL_WRITE (0x02)
30#define ACL_EXECUTE (0x01)
31//#define ACL_ADD (0x08)
32//#define ACL_DELETE (0x10)
33
34struct posix_acl_entry {
35 short e_tag;
36 unsigned short e_perm;
37 unsigned int e_id;
38};
39
40struct posix_acl {
41 atomic_t a_refcount;
42 unsigned int a_count;
43 struct posix_acl_entry a_entries[0];
44};
45
46#define FOREACH_ACL_ENTRY(pa, acl, pe) \
47 for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++)
48
49
50/*
51 * Duplicate an ACL handle.
52 */
53static inline struct posix_acl *
54posix_acl_dup(struct posix_acl *acl)
55{
56 if (acl)
57 atomic_inc(&acl->a_refcount);
58 return acl;
59}
60
61/*
62 * Free an ACL handle.
63 */
64static inline void
65posix_acl_release(struct posix_acl *acl)
66{
67 if (acl && atomic_dec_and_test(&acl->a_refcount))
68 kfree(acl);
69}
70
71
72/* posix_acl.c */
73
Al Virodd0fc662005-10-07 07:46:04 +0100[diff] [blame]74extern struct posix_acl *posix_acl_alloc(int, gfp_t);
75extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]76extern int posix_acl_valid(const struct posix_acl *);
77extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
Al Virodd0fc662005-10-07 07:46:04 +0100[diff] [blame]78extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]79extern int posix_acl_equiv_mode(const struct posix_acl *, mode_t *);
80extern int posix_acl_create_masq(struct posix_acl *, mode_t *);
81extern int posix_acl_chmod_masq(struct posix_acl *, mode_t);
82
83extern struct posix_acl *get_posix_acl(struct inode *, int);
84extern int set_posix_acl(struct inode *, int, struct posix_acl *);
85
Markus Trippelsdorf641cf4a2009-06-24 22:28:52 +0200[diff] [blame]86#ifdef CONFIG_FS_POSIX_ACL
Al Viro073aaa12009-06-09 12:11:54 -0400[diff] [blame]87static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
88{
89 struct posix_acl **p, *acl;
90 switch (type) {
91 case ACL_TYPE_ACCESS:
92 p = &inode->i_acl;
93 break;
94 case ACL_TYPE_DEFAULT:
95 p = &inode->i_default_acl;
96 break;
97 default:
98 return ERR_PTR(-EINVAL);
99 }
100 acl = ACCESS_ONCE(*p);
101 if (acl) {
102 spin_lock(&inode->i_lock);
103 acl = *p;
104 if (acl != ACL_NOT_CACHED)
105 acl = posix_acl_dup(acl);
106 spin_unlock(&inode->i_lock);
107 }
108 return acl;
109}
110
111static inline void set_cached_acl(struct inode *inode,
112 int type,
113 struct posix_acl *acl)
114{
115 struct posix_acl *old = NULL;
116 spin_lock(&inode->i_lock);
117 switch (type) {
118 case ACL_TYPE_ACCESS:
119 old = inode->i_acl;
120 inode->i_acl = posix_acl_dup(acl);
121 break;
122 case ACL_TYPE_DEFAULT:
123 old = inode->i_default_acl;
124 inode->i_default_acl = posix_acl_dup(acl);
125 break;
126 }
127 spin_unlock(&inode->i_lock);
128 if (old != ACL_NOT_CACHED)
129 posix_acl_release(old);
130}
131
132static inline void forget_cached_acl(struct inode *inode, int type)
133{
134 struct posix_acl *old = NULL;
135 spin_lock(&inode->i_lock);
136 switch (type) {
137 case ACL_TYPE_ACCESS:
138 old = inode->i_acl;
139 inode->i_acl = ACL_NOT_CACHED;
140 break;
141 case ACL_TYPE_DEFAULT:
142 old = inode->i_default_acl;
143 inode->i_default_acl = ACL_NOT_CACHED;
144 break;
145 }
146 spin_unlock(&inode->i_lock);
147 if (old != ACL_NOT_CACHED)
148 posix_acl_release(old);
149}
Markus Trippelsdorf641cf4a2009-06-24 22:28:52 +0200[diff] [blame]150#endif
Al Viro72c04902009-06-24 16:58:48 -0400[diff] [blame]151
152static inline void cache_no_acl(struct inode *inode)
153{
154#ifdef CONFIG_FS_POSIX_ACL
155 inode->i_acl = NULL;
156 inode->i_default_acl = NULL;
157#endif
158}
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]160#endif /* __LINUX_POSIX_ACL_H */