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 | ||
f61f6da0 | 74 | extern void posix_acl_init(struct posix_acl *, int); |
dd0fc66f AV |
75 | extern struct posix_acl *posix_acl_alloc(int, gfp_t); |
76 | extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t); | |
1da177e4 LT |
77 | extern int posix_acl_valid(const struct posix_acl *); |
78 | extern int posix_acl_permission(struct inode *, const struct posix_acl *, int); | |
dd0fc66f | 79 | extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t); |
1da177e4 LT |
80 | extern int posix_acl_equiv_mode(const struct posix_acl *, mode_t *); |
81 | extern int posix_acl_create_masq(struct posix_acl *, mode_t *); | |
82 | extern int posix_acl_chmod_masq(struct posix_acl *, mode_t); | |
83 | ||
84 | extern struct posix_acl *get_posix_acl(struct inode *, int); | |
85 | extern int set_posix_acl(struct inode *, int, struct posix_acl *); | |
86 | ||
641cf4a6 | 87 | #ifdef CONFIG_FS_POSIX_ACL |
073aaa1b AV |
88 | static inline struct posix_acl *get_cached_acl(struct inode *inode, int type) |
89 | { | |
90 | struct posix_acl **p, *acl; | |
91 | switch (type) { | |
92 | case ACL_TYPE_ACCESS: | |
93 | p = &inode->i_acl; | |
94 | break; | |
95 | case ACL_TYPE_DEFAULT: | |
96 | p = &inode->i_default_acl; | |
97 | break; | |
98 | default: | |
99 | return ERR_PTR(-EINVAL); | |
100 | } | |
101 | acl = ACCESS_ONCE(*p); | |
102 | if (acl) { | |
103 | spin_lock(&inode->i_lock); | |
104 | acl = *p; | |
105 | if (acl != ACL_NOT_CACHED) | |
106 | acl = posix_acl_dup(acl); | |
107 | spin_unlock(&inode->i_lock); | |
108 | } | |
109 | return acl; | |
110 | } | |
111 | ||
1e1743eb NP |
112 | static inline int negative_cached_acl(struct inode *inode, int type) |
113 | { | |
114 | struct posix_acl **p, *acl; | |
115 | switch (type) { | |
116 | case ACL_TYPE_ACCESS: | |
117 | p = &inode->i_acl; | |
118 | break; | |
119 | case ACL_TYPE_DEFAULT: | |
120 | p = &inode->i_default_acl; | |
121 | break; | |
122 | default: | |
123 | BUG(); | |
124 | } | |
125 | acl = ACCESS_ONCE(*p); | |
126 | if (acl) | |
127 | return 0; | |
128 | return 1; | |
129 | } | |
130 | ||
073aaa1b AV |
131 | static inline void set_cached_acl(struct inode *inode, |
132 | int type, | |
133 | struct posix_acl *acl) | |
134 | { | |
135 | struct posix_acl *old = NULL; | |
136 | spin_lock(&inode->i_lock); | |
137 | switch (type) { | |
138 | case ACL_TYPE_ACCESS: | |
139 | old = inode->i_acl; | |
140 | inode->i_acl = posix_acl_dup(acl); | |
141 | break; | |
142 | case ACL_TYPE_DEFAULT: | |
143 | old = inode->i_default_acl; | |
144 | inode->i_default_acl = posix_acl_dup(acl); | |
145 | break; | |
146 | } | |
147 | spin_unlock(&inode->i_lock); | |
148 | if (old != ACL_NOT_CACHED) | |
149 | posix_acl_release(old); | |
150 | } | |
151 | ||
152 | static inline void forget_cached_acl(struct inode *inode, int type) | |
153 | { | |
154 | struct posix_acl *old = NULL; | |
155 | spin_lock(&inode->i_lock); | |
156 | switch (type) { | |
157 | case ACL_TYPE_ACCESS: | |
158 | old = inode->i_acl; | |
159 | inode->i_acl = ACL_NOT_CACHED; | |
160 | break; | |
161 | case ACL_TYPE_DEFAULT: | |
162 | old = inode->i_default_acl; | |
163 | inode->i_default_acl = ACL_NOT_CACHED; | |
164 | break; | |
165 | } | |
166 | spin_unlock(&inode->i_lock); | |
167 | if (old != ACL_NOT_CACHED) | |
168 | posix_acl_release(old); | |
169 | } | |
796bd952 SW |
170 | |
171 | static inline void forget_all_cached_acls(struct inode *inode) | |
172 | { | |
173 | struct posix_acl *old_access, *old_default; | |
174 | spin_lock(&inode->i_lock); | |
175 | old_access = inode->i_acl; | |
176 | old_default = inode->i_default_acl; | |
177 | inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED; | |
178 | spin_unlock(&inode->i_lock); | |
179 | if (old_access != ACL_NOT_CACHED) | |
180 | posix_acl_release(old_access); | |
181 | if (old_default != ACL_NOT_CACHED) | |
182 | posix_acl_release(old_default); | |
183 | } | |
641cf4a6 | 184 | #endif |
72c04902 AV |
185 | |
186 | static inline void cache_no_acl(struct inode *inode) | |
187 | { | |
188 | #ifdef CONFIG_FS_POSIX_ACL | |
189 | inode->i_acl = NULL; | |
190 | inode->i_default_acl = NULL; | |
191 | #endif | |
192 | } | |
193 | ||
1da177e4 | 194 | #endif /* __LINUX_POSIX_ACL_H */ |