root/include/linux/posix_acl.h

INCLUDED FROM

DEFINITIONS

1. posix_acl_dup
2. posix_acl_release
3. cache_no_acl
4. posix_acl_chmod
5. simple_acl_create
6. cache_no_acl
7. posix_acl_create
8. forget_all_cached_acls

/*
  File: linux/posix_acl.h

  (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/


#ifndef __LINUX_POSIX_ACL_H
#define __LINUX_POSIX_ACL_H

#include <linux/bug.h>
#include <linux/slab.h>
#include <linux/rcupdate.h>

#define ACL_UNDEFINED_ID        (-1)

/* a_type field in acl_user_posix_entry_t */
#define ACL_TYPE_ACCESS         (0x8000)
#define ACL_TYPE_DEFAULT        (0x4000)

/* e_tag entry in struct posix_acl_entry */
#define ACL_USER_OBJ            (0x01)
#define ACL_USER                (0x02)
#define ACL_GROUP_OBJ           (0x04)
#define ACL_GROUP               (0x08)
#define ACL_MASK                (0x10)
#define ACL_OTHER               (0x20)

/* permissions in the e_perm field */
#define ACL_READ                (0x04)
#define ACL_WRITE               (0x02)
#define ACL_EXECUTE             (0x01)
//#define ACL_ADD               (0x08)
//#define ACL_DELETE            (0x10)

struct posix_acl_entry {
        short                   e_tag;
        unsigned short          e_perm;
        union {
                kuid_t          e_uid;
                kgid_t          e_gid;
        };
};

struct posix_acl {
        union {
                atomic_t                a_refcount;
                struct rcu_head         a_rcu;
        };
        unsigned int            a_count;
        struct posix_acl_entry  a_entries[0];
};

#define FOREACH_ACL_ENTRY(pa, acl, pe) \
        for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++)


/*
 * Duplicate an ACL handle.
 */
static inline struct posix_acl *
posix_acl_dup(struct posix_acl *acl)
{
        if (acl)
                atomic_inc(&acl->a_refcount);
        return acl;
}

/*
 * Free an ACL handle.
 */
static inline void
posix_acl_release(struct posix_acl *acl)
{
        if (acl && atomic_dec_and_test(&acl->a_refcount))
                kfree_rcu(acl, a_rcu);
}


/* posix_acl.c */

extern void posix_acl_init(struct posix_acl *, int);
extern struct posix_acl *posix_acl_alloc(int, gfp_t);
extern int posix_acl_valid(const struct posix_acl *);
extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t);

extern struct posix_acl *get_posix_acl(struct inode *, int);
extern int set_posix_acl(struct inode *, int, struct posix_acl *);

#ifdef CONFIG_FS_POSIX_ACL
extern int posix_acl_chmod(struct inode *, umode_t);
extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **,
                struct posix_acl **);

extern int simple_set_acl(struct inode *, struct posix_acl *, int);
extern int simple_acl_create(struct inode *, struct inode *);

struct posix_acl **acl_by_type(struct inode *inode, int type);
struct posix_acl *get_cached_acl(struct inode *inode, int type);
struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type);
void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl);
void forget_cached_acl(struct inode *inode, int type);
void forget_all_cached_acls(struct inode *inode);

static inline void cache_no_acl(struct inode *inode)
{
        inode->i_acl = NULL;
        inode->i_default_acl = NULL;
}
#else
static inline int posix_acl_chmod(struct inode *inode, umode_t mode)
{
        return 0;
}

#define simple_set_acl          NULL

static inline int simple_acl_create(struct inode *dir, struct inode *inode)
{
        return 0;
}
static inline void cache_no_acl(struct inode *inode)
{
}

static inline int posix_acl_create(struct inode *inode, umode_t *mode,
                struct posix_acl **default_acl, struct posix_acl **acl)
{
        *default_acl = *acl = NULL;
        return 0;
}

static inline void forget_all_cached_acls(struct inode *inode)
{
}
#endif /* CONFIG_FS_POSIX_ACL */

struct posix_acl *get_acl(struct inode *inode, int type);

#endif  /* __LINUX_POSIX_ACL_H */