forked from mirrors/linux
76c12881a3
So far setns() was missing time namespace support. This was partially due to it simply not being implemented but also because vdso_join_timens() could still fail which made switching to multiple namespaces atomically problematic. This is now fixed so support CLONE_NEWTIME with setns() Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Andrei Vagin <avagin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: Dmitry Safonov <dima@arista.com> Link: https://lore.kernel.org/r/20200706154912.3248030-4-christian.brauner@ubuntu.com
139 lines
3.3 KiB
C
139 lines
3.3 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);
|
|
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 = ¤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 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 */
|