2 File: linux/posix_acl.h
4 (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org>
8 #ifndef __LINUX_POSIX_ACL_H
9 #define __LINUX_POSIX_ACL_H
11 #include <linux/slab.h>
13 #define ACL_UNDEFINED_ID (-1)
15 /* a_type field in acl_user_posix_entry_t */
16 #define ACL_TYPE_ACCESS (0x8000)
17 #define ACL_TYPE_DEFAULT (0x4000)
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)
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)
34 struct posix_acl_entry {
36 unsigned short e_perm;
43 struct posix_acl_entry a_entries[0];
46 #define FOREACH_ACL_ENTRY(pa, acl, pe) \
47 for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++)
51 * Duplicate an ACL handle.
53 static inline struct posix_acl *
54 posix_acl_dup(struct posix_acl *acl)
57 atomic_inc(&acl->a_refcount);
65 posix_acl_release(struct posix_acl *acl)
67 if (acl && atomic_dec_and_test(&acl->a_refcount))
74 extern void posix_acl_init(struct posix_acl *, int);
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);
77 extern int posix_acl_valid(const struct posix_acl *);
78 extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
79 extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t);
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 extern int posix_acl_chmod(struct posix_acl **, gfp_t, mode_t);
85 extern struct posix_acl *get_posix_acl(struct inode *, int);
86 extern int set_posix_acl(struct inode *, int, struct posix_acl *);
88 #ifdef CONFIG_FS_POSIX_ACL
89 static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
91 struct posix_acl **p, *acl;
96 case ACL_TYPE_DEFAULT:
97 p = &inode->i_default_acl;
100 return ERR_PTR(-EINVAL);
102 acl = ACCESS_ONCE(*p);
104 spin_lock(&inode->i_lock);
106 if (acl != ACL_NOT_CACHED)
107 acl = posix_acl_dup(acl);
108 spin_unlock(&inode->i_lock);
113 static inline int negative_cached_acl(struct inode *inode, int type)
115 struct posix_acl **p, *acl;
117 case ACL_TYPE_ACCESS:
120 case ACL_TYPE_DEFAULT:
121 p = &inode->i_default_acl;
126 acl = ACCESS_ONCE(*p);
132 static inline void set_cached_acl(struct inode *inode,
134 struct posix_acl *acl)
136 struct posix_acl *old = NULL;
137 spin_lock(&inode->i_lock);
139 case ACL_TYPE_ACCESS:
141 inode->i_acl = posix_acl_dup(acl);
143 case ACL_TYPE_DEFAULT:
144 old = inode->i_default_acl;
145 inode->i_default_acl = posix_acl_dup(acl);
148 spin_unlock(&inode->i_lock);
149 if (old != ACL_NOT_CACHED)
150 posix_acl_release(old);
153 static inline void forget_cached_acl(struct inode *inode, int type)
155 struct posix_acl *old = NULL;
156 spin_lock(&inode->i_lock);
158 case ACL_TYPE_ACCESS:
160 inode->i_acl = ACL_NOT_CACHED;
162 case ACL_TYPE_DEFAULT:
163 old = inode->i_default_acl;
164 inode->i_default_acl = ACL_NOT_CACHED;
167 spin_unlock(&inode->i_lock);
168 if (old != ACL_NOT_CACHED)
169 posix_acl_release(old);
172 static inline void forget_all_cached_acls(struct inode *inode)
174 struct posix_acl *old_access, *old_default;
175 spin_lock(&inode->i_lock);
176 old_access = inode->i_acl;
177 old_default = inode->i_default_acl;
178 inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
179 spin_unlock(&inode->i_lock);
180 if (old_access != ACL_NOT_CACHED)
181 posix_acl_release(old_access);
182 if (old_default != ACL_NOT_CACHED)
183 posix_acl_release(old_default);
187 static inline void cache_no_acl(struct inode *inode)
189 #ifdef CONFIG_FS_POSIX_ACL
191 inode->i_default_acl = NULL;
195 #endif /* __LINUX_POSIX_ACL_H */