um: expose time-travel mode to userspace side

This will be necessary in the userspace side to fix the
signal/interrupt handling in time-travel=ext mode, which
is the next patch.

Signed-off-by: Johannes Berg <[e-mail]>
Signed-off-by: Richard Weinberger <[e-mail]>

arch/um/include/linux/time-internal.h

···
 #define __TIMER_INTERNAL_H__
 #include <linux/list.h>
 #include <asm/bug.h>
+#include <shared/timetravel.h>
 
 #define TIMER_MULTIPLIER 256
 #define TIMER_MIN_DELTA  500
-
-enum time_travel_mode {
-	TT_MODE_OFF,
-	TT_MODE_BASIC,
-	TT_MODE_INFCPU,
-	TT_MODE_EXTERNAL,
-};
 
 #ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
 struct time_travel_event {
···
 	struct list_head list;
 	bool pending, onstack;
 };
-
-extern enum time_travel_mode time_travel_mode;
 
 void time_travel_sleep(void);
 
···
 #else
 struct time_travel_event {
 };
-
-#define time_travel_mode TT_MODE_OFF
 
 static inline void time_travel_sleep(void)
 {

arch/um/include/shared/timetravel.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019-2021 Intel Corporation
+ */
+#ifndef _UM_TIME_TRAVEL_H_
+#define _UM_TIME_TRAVEL_H_
+
+enum time_travel_mode {
+	TT_MODE_OFF,
+	TT_MODE_BASIC,
+	TT_MODE_INFCPU,
+	TT_MODE_EXTERNAL,
+};
+
+#if defined(UML_CONFIG_UML_TIME_TRAVEL_SUPPORT) || \
+    defined(CONFIG_UML_TIME_TRAVEL_SUPPORT)
+extern enum time_travel_mode time_travel_mode;
+#else
+#define time_travel_mode TT_MODE_OFF
+#endif /* (UML_)CONFIG_UML_TIME_TRAVEL_SUPPORT */
+
+#endif /* _UM_TIME_TRAVEL_H_ */