[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
extern int vdso_join_timens(struct task_struct *task,
			    struct time_namespace *ns);
extern void timens_commit(struct task_struct *tsk, struct time_namespace *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);
}

void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m);

struct proc_timens_offset {
	int			clockid;
	struct timespec64	val;
};

int proc_timens_set_offset(struct file *file, struct task_struct *p,
			   struct proc_timens_offset *offsets, int n);

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 int vdso_join_timens(struct task_struct *task,
				   struct time_namespace *ns)
{
	return 0;
}

static inline void timens_commit(struct task_struct *tsk,
				 struct time_namespace *ns)
{
}

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
70ddf651 DS	34	extern int vdso_join_timens(struct task_struct *task,
70ddf651 DS	35	struct time_namespace *ns);
76c12881	36	extern void timens_commit(struct task_struct tsk, struct time_namespace ns);
70ddf651	37
769071ac AV	38	static inline struct time_namespace get_time_ns(struct time_namespace ns)
	39	{
	40	kref_get(&ns->kref);
	41	return ns;
	42	}
	43
	44	struct time_namespace *copy_time_ns(unsigned long flags,
	45	struct user_namespace *user_ns,
	46	struct time_namespace *old_ns);
	47	void free_time_ns(struct kref *kref);
	48	int timens_on_fork(struct nsproxy nsproxy, struct task_struct tsk);
64b302ab	49	struct vdso_data arch_get_vdso_data(void vvar_page);
769071ac AV	50
	51	static inline void put_time_ns(struct time_namespace *ns)
	52	{
	53	kref_put(&ns->kref, free_time_ns);
	54	}
	55
04a8682a AV	56	void proc_timens_show_offsets(struct task_struct p, struct seq_file m);
	57
	58	struct proc_timens_offset {
	59	int clockid;
	60	struct timespec64 val;
	61	};
	62
	63	int proc_timens_set_offset(struct file file, struct task_struct p,
	64	struct proc_timens_offset *offsets, int n);
	65
af993f58 AV	66	static inline void timens_add_monotonic(struct timespec64 *ts)
	67	{
	68	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	69
	70	ts = timespec64_add(ts, ns_offsets->monotonic);
	71	}
	72
	73	static inline void timens_add_boottime(struct timespec64 *ts)
	74	{
	75	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	76
	77	ts = timespec64_add(ts, ns_offsets->boottime);
	78	}
	79
89dd8eec AV	80	ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
	81	struct timens_offsets *offsets);
	82
	83	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	84	{
	85	struct time_namespace *ns = current->nsproxy->time_ns;
	86
	87	if (likely(ns == &init_time_ns))
	88	return tim;
	89
	90	return do_timens_ktime_to_host(clockid, tim, &ns->offsets);
	91	}
	92
769071ac	93	#else
70ddf651 DS	94	static inline int vdso_join_timens(struct task_struct *task,
	95	struct time_namespace *ns)
	96	{
	97	return 0;
	98	}
	99
76c12881 CB	100	static inline void timens_commit(struct task_struct *tsk,
	101	struct time_namespace *ns)
	102	{
	103	}
	104
769071ac AV	105	static inline struct time_namespace get_time_ns(struct time_namespace ns)
	106	{
	107	return NULL;
	108	}
	109
	110	static inline void put_time_ns(struct time_namespace *ns)
	111	{
	112	}
	113
	114	static inline
	115	struct time_namespace *copy_time_ns(unsigned long flags,
	116	struct user_namespace *user_ns,
	117	struct time_namespace *old_ns)
	118	{
	119	if (flags & CLONE_NEWTIME)
	120	return ERR_PTR(-EINVAL);
	121
	122	return old_ns;
	123	}
	124
	125	static inline int timens_on_fork(struct nsproxy *nsproxy,
	126	struct task_struct *tsk)
	127	{
	128	return 0;
	129	}
	130
af993f58 AV	131	static inline void timens_add_monotonic(struct timespec64 *ts) { }
af993f58 AV	132	static inline void timens_add_boottime(struct timespec64 *ts) { }
89dd8eec AV	133	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	134	{
	135	return tim;
	136	}
769071ac AV	137	#endif
	138
	139	#endif /* _LINUX_TIMENS_H */