Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | ||
34 | struct posix_acl_entry { | |
35 | short e_tag; | |
36 | unsigned short e_perm; | |
37 | unsigned int e_id; | |
38 | }; | |
39 | ||
40 | struct 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 | */ | |
53 | static inline struct posix_acl * | |
54 | posix_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 | */ | |
64 | static inline void | |
65 | posix_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 | ||
dd0fc66f AV |
74 | extern struct posix_acl *posix_acl_alloc(int, gfp_t); |
75 | extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t); | |
1da177e4 LT |
76 | extern int posix_acl_valid(const struct posix_acl *); |
77 | extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); | |
dd0fc66f | 78 | extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t); |
1da177e4 LT |
79 | extern int posix_acl_equiv_mode(const struct posix_acl *, mode_t *); |
80 | extern int posix_acl_create_masq(struct posix_acl *, mode_t *); | |
81 | extern int posix_acl_chmod_masq(struct posix_acl *, mode_t); | |
82 | ||
83 | extern struct posix_acl *get_posix_acl(struct inode *, int); | |
84 | extern int set_posix_acl(struct inode *, int, struct posix_acl *); | |
85 | ||
641cf4a6 | 86 | #ifdef CONFIG_FS_POSIX_ACL |
073aaa1b AV |
87 | static 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 | ||
111 | static 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 | ||
132 | static 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 | } | |
796bd952 SW |
150 | |
151 | static inline void forget_all_cached_acls(struct inode *inode) | |
152 | { | |
153 | struct posix_acl *old_access, *old_default; | |
154 | spin_lock(&inode->i_lock); | |
155 | old_access = inode->i_acl; | |
156 | old_default = inode->i_default_acl; | |
157 | inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED; | |
158 | spin_unlock(&inode->i_lock); | |
159 | if (old_access != ACL_NOT_CACHED) | |
160 | posix_acl_release(old_access); | |
161 | if (old_default != ACL_NOT_CACHED) | |
162 | posix_acl_release(old_default); | |
163 | } | |
641cf4a6 | 164 | #endif |
72c04902 AV |
165 | |
166 | static inline void cache_no_acl(struct inode *inode) | |
167 | { | |
168 | #ifdef CONFIG_FS_POSIX_ACL | |
169 | inode->i_acl = NULL; | |
170 | inode->i_default_acl = NULL; | |
171 | #endif | |
172 | } | |
173 | ||
1da177e4 | 174 | #endif /* __LINUX_POSIX_ACL_H */ |