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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PROJID_H
#define _LINUX_PROJID_H
/*
* A set of types for the internal kernel types representing project ids.
*
* The types defined in this header allow distinguishing which project ids in
* the kernel are values used by userspace and which project id values are
* the internal kernel values. With the addition of user namespaces the values
* can be different. Using the type system makes it possible for the compiler
* to detect when we overlook these differences.
*
*/
#include <linux/types.h>
struct user_namespace;
extern struct user_namespace init_user_ns;
typedef __kernel_uid32_t projid_t;
typedef struct {
projid_t val;
} kprojid_t;
static inline projid_t __kprojid_val(kprojid_t projid)
{
return projid.val;
}
#define KPROJIDT_INIT(value) (kprojid_t){ value }
#define INVALID_PROJID KPROJIDT_INIT(-1)
#define OVERFLOW_PROJID 65534
static inline bool projid_eq(kprojid_t left, kprojid_t right)
{
return __kprojid_val(left) == __kprojid_val(right);
}
static inline bool projid_lt(kprojid_t left, kprojid_t right)
{
return __kprojid_val(left) < __kprojid_val(right);
}
static inline bool projid_valid(kprojid_t projid)
{
return !projid_eq(projid, INVALID_PROJID);
}
#ifdef CONFIG_USER_NS
extern kprojid_t make_kprojid(struct user_namespace *from, projid_t projid);
extern projid_t from_kprojid(struct user_namespace *to, kprojid_t projid);
extern projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t projid);
static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
{
return from_kprojid(ns, projid) != (projid_t)-1;
}
#else
static inline kprojid_t make_kprojid(struct user_namespace *from, projid_t projid)
{
return KPROJIDT_INIT(projid);
}
static inline projid_t from_kprojid(struct user_namespace *to, kprojid_t kprojid)
{
return __kprojid_val(kprojid);
}
static inline projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t kprojid)
{
projid_t projid = from_kprojid(to, kprojid);
if (projid == (projid_t)-1)
projid = OVERFLOW_PROJID;
return projid;
}
static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
{
return true;
}
#endif /* CONFIG_USER_NS */
#endif /* _LINUX_PROJID_H */
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