[mirror_ubuntu-jammy-kernel.git] / include / linux / time_namespace.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_TIMENS_H
#define _LINUX_TIMENS_H


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

struct user_namespace;
extern struct user_namespace init_user_ns;

struct timens_offsets {
	struct timespec64 monotonic;
	struct timespec64 boottime;
};

struct time_namespace {
	struct kref		kref;
	struct user_namespace	*user_ns;
	struct ucounts		*ucounts;
	struct ns_common	ns;
	struct timens_offsets	offsets;
	struct page		*vvar_page;
	/* If set prevents changing offsets after any task joined namespace. */
	bool			frozen_offsets;
} __randomize_layout;

extern struct time_namespace init_time_ns;

#ifdef CONFIG_TIME_NS
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
{
	kref_get(&ns->kref);
	return ns;
}

struct time_namespace *copy_time_ns(unsigned long flags,
				    struct user_namespace *user_ns,
				    struct time_namespace *old_ns);
void free_time_ns(struct kref *kref);
int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
struct vdso_data *arch_get_vdso_data(void *vvar_page);

static inline void put_time_ns(struct time_namespace *ns)
{
	kref_put(&ns->kref, free_time_ns);
}

static inline void timens_add_monotonic(struct timespec64 *ts)
{
	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;

	*ts = timespec64_add(*ts, ns_offsets->monotonic);
}

static inline void timens_add_boottime(struct timespec64 *ts)
{
	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;

	*ts = timespec64_add(*ts, ns_offsets->boottime);
}

ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
				struct timens_offsets *offsets);

static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
{
	struct time_namespace *ns = current->nsproxy->time_ns;

	if (likely(ns == &init_time_ns))
		return tim;

	return do_timens_ktime_to_host(clockid, tim, &ns->offsets);
}

#else
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
{
	return NULL;
}

static inline void put_time_ns(struct time_namespace *ns)
{
}

static inline
struct time_namespace *copy_time_ns(unsigned long flags,
				    struct user_namespace *user_ns,
				    struct time_namespace *old_ns)
{
	if (flags & CLONE_NEWTIME)
		return ERR_PTR(-EINVAL);

	return old_ns;
}

static inline int timens_on_fork(struct nsproxy *nsproxy,
				 struct task_struct *tsk)
{
	return 0;
}

static inline void timens_add_monotonic(struct timespec64 *ts) { }
static inline void timens_add_boottime(struct timespec64 *ts) { }
static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
{
	return tim;
}
#endif

#endif /* _LINUX_TIMENS_H */
Commit	Line	Data
769071ac AV	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _LINUX_TIMENS_H
	3	#define _LINUX_TIMENS_H
	4
	5
	6	#include <linux/sched.h>
	7	#include <linux/kref.h>
	8	#include <linux/nsproxy.h>
	9	#include <linux/ns_common.h>
	10	#include <linux/err.h>
	11
	12	struct user_namespace;
	13	extern struct user_namespace init_user_ns;
	14
af993f58 AV	15	struct timens_offsets {
	16	struct timespec64 monotonic;
	17	struct timespec64 boottime;
	18	};
	19
769071ac AV	20	struct time_namespace {
	21	struct kref kref;
	22	struct user_namespace *user_ns;
	23	struct ucounts *ucounts;
	24	struct ns_common ns;
af993f58	25	struct timens_offsets offsets;
afaa7b5a DS	26	struct page *vvar_page;
	27	/* If set prevents changing offsets after any task joined namespace. */
	28	bool frozen_offsets;
769071ac AV	29	} __randomize_layout;
	30
	31	extern struct time_namespace init_time_ns;
	32
	33	#ifdef CONFIG_TIME_NS
	34	static inline struct time_namespace get_time_ns(struct time_namespace ns)
	35	{
	36	kref_get(&ns->kref);
	37	return ns;
	38	}
	39
	40	struct time_namespace *copy_time_ns(unsigned long flags,
	41	struct user_namespace *user_ns,
	42	struct time_namespace *old_ns);
	43	void free_time_ns(struct kref *kref);
	44	int timens_on_fork(struct nsproxy nsproxy, struct task_struct tsk);
64b302ab	45	struct vdso_data arch_get_vdso_data(void vvar_page);
769071ac AV	46
	47	static inline void put_time_ns(struct time_namespace *ns)
	48	{
	49	kref_put(&ns->kref, free_time_ns);
	50	}
	51
af993f58 AV	52	static inline void timens_add_monotonic(struct timespec64 *ts)
	53	{
	54	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	55
	56	ts = timespec64_add(ts, ns_offsets->monotonic);
	57	}
	58
	59	static inline void timens_add_boottime(struct timespec64 *ts)
	60	{
	61	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	62
	63	ts = timespec64_add(ts, ns_offsets->boottime);
	64	}
	65
89dd8eec AV	66	ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
	67	struct timens_offsets *offsets);
	68
	69	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	70	{
	71	struct time_namespace *ns = current->nsproxy->time_ns;
	72
	73	if (likely(ns == &init_time_ns))
	74	return tim;
	75
	76	return do_timens_ktime_to_host(clockid, tim, &ns->offsets);
	77	}
	78
769071ac AV	79	#else
	80	static inline struct time_namespace get_time_ns(struct time_namespace ns)
	81	{
	82	return NULL;
	83	}
	84
	85	static inline void put_time_ns(struct time_namespace *ns)
	86	{
	87	}
	88
	89	static inline
	90	struct time_namespace *copy_time_ns(unsigned long flags,
	91	struct user_namespace *user_ns,
	92	struct time_namespace *old_ns)
	93	{
	94	if (flags & CLONE_NEWTIME)
	95	return ERR_PTR(-EINVAL);
	96
	97	return old_ns;
	98	}
	99
	100	static inline int timens_on_fork(struct nsproxy *nsproxy,
	101	struct task_struct *tsk)
	102	{
	103	return 0;
	104	}
	105
af993f58 AV	106	static inline void timens_add_monotonic(struct timespec64 *ts) { }
af993f58 AV	107	static inline void timens_add_boottime(struct timespec64 *ts) { }
89dd8eec AV	108	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	109	{
	110	return tim;
	111	}
769071ac AV	112	#endif
	113
	114	#endif /* _LINUX_TIMENS_H */