1 files changed, 133 insertions, 0 deletions
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
new file mode 100644
index 000000000000..824d54e057eb
--- /dev/null
+++ b/include/linux/time_namespace.h
@@ -0,0 +1,133 @@
+/* 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 = &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 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 */