[linux-block.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/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 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)
{
	refcount_inc(&ns->ns.count);
	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 time_namespace *ns);
void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
struct vdso_data *arch_get_vdso_data(void *vvar_page);
struct page *find_timens_vvar_page(struct vm_area_struct *vma);

static inline void put_time_ns(struct time_namespace *ns)
{
	if (refcount_dec_and_test(&ns->ns.count))
		free_time_ns(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);
}

static inline u64 timens_add_boottime_ns(u64 nsec)
{
	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;

	return nsec + timespec64_to_ns(&ns_offsets->boottime);
}

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

	*ts = timespec64_sub(*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 void timens_on_fork(struct nsproxy *nsproxy,
				 struct task_struct *tsk)
{
	return;
}

static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma)
{
	return NULL;
}

static inline void timens_add_monotonic(struct timespec64 *ts) { }
static inline void timens_add_boottime(struct timespec64 *ts) { }

static inline u64 timens_add_boottime_ns(u64 nsec)
{
	return nsec;
}

static inline void timens_sub_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>
769071ac AV	7	#include <linux/nsproxy.h>
	8	#include <linux/ns_common.h>
	9	#include <linux/err.h>
	10
	11	struct user_namespace;
	12	extern struct user_namespace init_user_ns;
	13
af993f58 AV	14	struct timens_offsets {
	15	struct timespec64 monotonic;
	16	struct timespec64 boottime;
	17	};
	18
769071ac	19	struct time_namespace {
769071ac AV	20	struct user_namespace *user_ns;
	21	struct ucounts *ucounts;
	22	struct ns_common ns;
af993f58	23	struct timens_offsets offsets;
afaa7b5a DS	24	struct page *vvar_page;
	25	/* If set prevents changing offsets after any task joined namespace. */
	26	bool frozen_offsets;
769071ac AV	27	} __randomize_layout;
	28
	29	extern struct time_namespace init_time_ns;
	30
	31	#ifdef CONFIG_TIME_NS
70ddf651 DS	32	extern int vdso_join_timens(struct task_struct *task,
70ddf651 DS	33	struct time_namespace *ns);
76c12881	34	extern void timens_commit(struct task_struct tsk, struct time_namespace ns);
70ddf651	35
769071ac AV	36	static inline struct time_namespace get_time_ns(struct time_namespace ns)
769071ac AV	37	{
28c41efd	38	refcount_inc(&ns->ns.count);
769071ac AV	39	return ns;
	40	}
	41
	42	struct time_namespace *copy_time_ns(unsigned long flags,
	43	struct user_namespace *user_ns,
	44	struct time_namespace *old_ns);
28c41efd	45	void free_time_ns(struct time_namespace *ns);
5c62634f	46	void timens_on_fork(struct nsproxy nsproxy, struct task_struct tsk);
64b302ab	47	struct vdso_data arch_get_vdso_data(void vvar_page);
d6c494e8	48	struct page find_timens_vvar_page(struct vm_area_struct vma);
769071ac AV	49
	50	static inline void put_time_ns(struct time_namespace *ns)
	51	{
28c41efd KT	52	if (refcount_dec_and_test(&ns->ns.count))
28c41efd KT	53	free_time_ns(ns);
769071ac AV	54	}
769071ac AV	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
31909e33 MW	80	static inline u64 timens_add_boottime_ns(u64 nsec)
	81	{
	82	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	83
	84	return nsec + timespec64_to_ns(&ns_offsets->boottime);
	85	}
	86
	87	static inline void timens_sub_boottime(struct timespec64 *ts)
	88	{
	89	struct timens_offsets *ns_offsets = &current->nsproxy->time_ns->offsets;
	90
	91	ts = timespec64_sub(ts, ns_offsets->boottime);
	92	}
	93
89dd8eec AV	94	ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
	95	struct timens_offsets *offsets);
	96
	97	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	98	{
	99	struct time_namespace *ns = current->nsproxy->time_ns;
	100
	101	if (likely(ns == &init_time_ns))
	102	return tim;
	103
	104	return do_timens_ktime_to_host(clockid, tim, &ns->offsets);
	105	}
	106
769071ac	107	#else
70ddf651 DS	108	static inline int vdso_join_timens(struct task_struct *task,
	109	struct time_namespace *ns)
	110	{
	111	return 0;
	112	}
	113
76c12881 CB	114	static inline void timens_commit(struct task_struct *tsk,
	115	struct time_namespace *ns)
	116	{
	117	}
	118
769071ac AV	119	static inline struct time_namespace get_time_ns(struct time_namespace ns)
	120	{
	121	return NULL;
	122	}
	123
	124	static inline void put_time_ns(struct time_namespace *ns)
	125	{
	126	}
	127
	128	static inline
	129	struct time_namespace *copy_time_ns(unsigned long flags,
	130	struct user_namespace *user_ns,
	131	struct time_namespace *old_ns)
	132	{
	133	if (flags & CLONE_NEWTIME)
	134	return ERR_PTR(-EINVAL);
	135
	136	return old_ns;
	137	}
	138
5c62634f	139	static inline void timens_on_fork(struct nsproxy *nsproxy,
769071ac AV	140	struct task_struct *tsk)
769071ac AV	141	{
5c62634f	142	return;
769071ac AV	143	}
769071ac AV	144
d6c494e8 JH	145	static inline struct page find_timens_vvar_page(struct vm_area_struct vma)
	146	{
	147	return NULL;
	148	}
	149
af993f58 AV	150	static inline void timens_add_monotonic(struct timespec64 *ts) { }
af993f58 AV	151	static inline void timens_add_boottime(struct timespec64 *ts) { }
31909e33 MW	152
	153	static inline u64 timens_add_boottime_ns(u64 nsec)
	154	{
	155	return nsec;
	156	}
	157
	158	static inline void timens_sub_boottime(struct timespec64 *ts) { }
	159
89dd8eec AV	160	static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
	161	{
	162	return tim;
	163	}
769071ac AV	164	#endif
	165
	166	#endif /* _LINUX_TIMENS_H */