1 files changed, 117 insertions, 0 deletions
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
new file mode 100644
index 000000000..90f6de224
--- /dev/null
+++ b/arch/um/os-Linux/time.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
+ * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
+ * Copyright (C) 2012-2014 Cisco Systems
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
+ */
+
+#include <stddef.h>
+#include <errno.h>
+#include <signal.h>
+#include <time.h>
+#include <sys/time.h>
+#include <kern_util.h>
+#include <os.h>
+#include <string.h>
+
+static timer_t event_high_res_timer = 0;
+
+static inline long long timeval_to_ns(const struct timeval *tv)
+{
+	return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
+		tv->tv_usec * UM_NSEC_PER_USEC;
+}
+
+static inline long long timespec_to_ns(const struct timespec *ts)
+{
+	return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) + ts->tv_nsec;
+}
+
+long long os_persistent_clock_emulation(void)
+{
+	struct timespec realtime_tp;
+
+	clock_gettime(CLOCK_REALTIME, &realtime_tp);
+	return timespec_to_ns(&realtime_tp);
+}
+
+/**
+ * os_timer_create() - create an new posix (interval) timer
+ */
+int os_timer_create(void)
+{
+	timer_t *t = &event_high_res_timer;
+
+	if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1)
+		return -1;
+
+	return 0;
+}
+
+int os_timer_set_interval(unsigned long long nsecs)
+{
+	struct itimerspec its;
+
+	its.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC;
+	its.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC;
+
+	its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC;
+	its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC;
+
+	if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1)
+		return -errno;
+
+	return 0;
+}
+
+int os_timer_one_shot(unsigned long long nsecs)
+{
+	struct itimerspec its = {
+		.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC,
+		.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC,
+
+		.it_interval.tv_sec = 0,
+		.it_interval.tv_nsec = 0, // we cheat here
+	};
+
+	timer_settime(event_high_res_timer, 0, &its, NULL);
+	return 0;
+}
+
+/**
+ * os_timer_disable() - disable the posix (interval) timer
+ */
+void os_timer_disable(void)
+{
+	struct itimerspec its;
+
+	memset(&its, 0, sizeof(struct itimerspec));
+	timer_settime(event_high_res_timer, 0, &its, NULL);
+}
+
+long long os_nsecs(void)
+{
+	struct timespec ts;
+
+	clock_gettime(CLOCK_MONOTONIC,&ts);
+	return timespec_to_ns(&ts);
+}
+
+/**
+ * os_idle_sleep() - sleep for a given time of nsecs
+ * @nsecs: nanoseconds to sleep
+ */
+void os_idle_sleep(unsigned long long nsecs)
+{
+	struct timespec ts = {
+		.tv_sec  = nsecs / UM_NSEC_PER_SEC,
+		.tv_nsec = nsecs % UM_NSEC_PER_SEC
+	};
+
+	/*
+	 * Relay the signal if clock_nanosleep is interrupted.
+	 */
+	if (clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL))
+		deliver_alarm();
+}