[PATCHv7 09/33] posix-clocks: Wire up clock_gettime() with timens offsets

[Dmitry Safonov <dima@arista.com>]

From: Andrei Vagin <avagin@openvz.org>

Adjust monotonic and boottime clocks with per-timens offsets.
As the result a process inside time namespace will see timers and clocks
corrected to offsets that were set on creating namespace.

Note that applications usually go through vDSO to get time, which is not
yet adjusted. Further changes complete time namespace virtualisation
with vDSO support.

Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
 kernel/time/alarmtimer.c   | 1 +
 kernel/time/posix-stubs.c  | 3 +++
 kernel/time/posix-timers.c | 5 +++++
 3 files changed, 9 insertions(+)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 9415c83f8cca..c326427bb4cb 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -26,6 +26,7 @@
 #include <linux/freezer.h>
 #include <linux/compat.h>
 #include <linux/module.h>
+#include <linux/time_namespace.h>
 
 #include "posix-timers.h"
 
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 67df65f887ac..edaf075d1ee4 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -14,6 +14,7 @@
 #include <linux/ktime.h>
 #include <linux/timekeeping.h>
 #include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
 #include <linux/compat.h>
 
 #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
@@ -77,9 +78,11 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
 		break;
 	case CLOCK_MONOTONIC:
 		ktime_get_ts64(tp);
+		timens_add_monotonic(tp);
 		break;
 	case CLOCK_BOOTTIME:
 		ktime_get_boottime_ts64(tp);
+		timens_add_boottime(tp);
 		break;
 	default:
 		return -EINVAL;
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 47a8d43fe1c6..d8b5bd4cbae1 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -30,6 +30,7 @@
 #include <linux/hashtable.h>
 #include <linux/compat.h>
 #include <linux/nospec.h>
+#include <linux/time_namespace.h>
 
 #include "timekeeping.h"
 #include "posix-timers.h"
@@ -195,6 +196,7 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
 static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
 {
 	ktime_get_ts64(tp);
+	timens_add_monotonic(tp);
 	return 0;
 }
 
@@ -209,6 +211,7 @@ static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
 static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
 {
 	ktime_get_raw_ts64(tp);
+	timens_add_monotonic(tp);
 	return 0;
 }
 
@@ -223,6 +226,7 @@ static int posix_get_monotonic_coarse(clockid_t which_clock,
 						struct timespec64 *tp)
 {
 	ktime_get_coarse_ts64(tp);
+	timens_add_monotonic(tp);
 	return 0;
 }
 
@@ -235,6 +239,7 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
 int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
 {
 	ktime_get_boottime_ts64(tp);
+	timens_add_boottime(tp);
 	return 0;
 }
 
-- 
2.23.0