[mirror_ubuntu-bionic-kernel.git] / include / linux / user_namespace.h

#ifndef _LINUX_USER_NAMESPACE_H
#define _LINUX_USER_NAMESPACE_H

#include <linux/kref.h>
#include <linux/nsproxy.h>
#include <linux/sched.h>
#include <linux/err.h>

#define UIDHASH_BITS	(CONFIG_BASE_SMALL ? 3 : 8)
#define UIDHASH_SZ	(1 << UIDHASH_BITS)

struct user_namespace {
	struct kref		kref;
	struct list_head	uidhash_table[UIDHASH_SZ];
	struct user_struct	*root_user;
};

extern struct user_namespace init_user_ns;

#ifdef CONFIG_USER_NS

static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
{
	if (ns)
		kref_get(&ns->kref);
	return ns;
}

extern struct user_namespace *copy_user_ns(int flags,
					   struct user_namespace *old_ns);
extern void free_user_ns(struct kref *kref);

static inline void put_user_ns(struct user_namespace *ns)
{
	if (ns)
		kref_put(&ns->kref, free_user_ns);
}

#else

static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
{
	return &init_user_ns;
}

static inline struct user_namespace *copy_user_ns(int flags,
						  struct user_namespace *old_ns)
{
	if (flags & CLONE_NEWUSER)
		return ERR_PTR(-EINVAL);

	return NULL;
}

static inline void put_user_ns(struct user_namespace *ns)
{
}

#endif

#endif /* _LINUX_USER_H */
Commit	Line	Data
acce292c CLG	1	#ifndef _LINUX_USER_NAMESPACE_H
	2	#define _LINUX_USER_NAMESPACE_H
	3
	4	#include <linux/kref.h>
	5	#include <linux/nsproxy.h>
	6	#include <linux/sched.h>
77ec739d	7	#include <linux/err.h>
acce292c CLG	8
	9	#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 8)
	10	#define UIDHASH_SZ (1 << UIDHASH_BITS)
	11
	12	struct user_namespace {
	13	struct kref kref;
	14	struct list_head uidhash_table[UIDHASH_SZ];
	15	struct user_struct *root_user;
	16	};
	17
	18	extern struct user_namespace init_user_ns;
	19
	20	#ifdef CONFIG_USER_NS
	21
	22	static inline struct user_namespace get_user_ns(struct user_namespace ns)
	23	{
	24	if (ns)
	25	kref_get(&ns->kref);
	26	return ns;
	27	}
	28
	29	extern struct user_namespace *copy_user_ns(int flags,
	30	struct user_namespace *old_ns);
	31	extern void free_user_ns(struct kref *kref);
	32
	33	static inline void put_user_ns(struct user_namespace *ns)
	34	{
	35	if (ns)
	36	kref_put(&ns->kref, free_user_ns);
	37	}
	38
	39	#else
	40
	41	static inline struct user_namespace get_user_ns(struct user_namespace ns)
	42	{
	43	return &init_user_ns;
	44	}
	45
	46	static inline struct user_namespace *copy_user_ns(int flags,
	47	struct user_namespace *old_ns)
	48	{
77ec739d SH	49	if (flags & CLONE_NEWUSER)
	50	return ERR_PTR(-EINVAL);
	51
acce292c CLG	52	return NULL;
	53	}
	54
	55	static inline void put_user_ns(struct user_namespace *ns)
	56	{
	57	}
	58
	59	#endif
	60
	61	#endif /* _LINUX_USER_H */