forked from mirrors/linux
		
	API to set time namespace offsets for children processes, i.e.: echo "$clockid $offset_sec $offset_nsec" > /proc/self/timens_offsets Co-developed-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-28-dima@arista.com
		
			
				
	
	
		
			133 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			133 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* 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);
 | 
						|
 | 
						|
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 = ¤t->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 = ¤t->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 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 */
 |