svn commit: r298929 - head/sys/dev/xen/timer

[Roger Pau Monné]

Author: royger
Date: Mon May  2 16:15:28 2016
New Revision: 298929
URL: https://svnweb.freebsd.org/changeset/base/298929

Log:
  xen/time: allow Dom0 to set the host time
  
  Dom0 should be able to set the host time. This is implemented by first
  writing to the RTC (as would be done on bare metal), and then using the
  XENPF_settime64 hypercall in order to force Xen to update the wallclock
  shared page of all domains.
  
  Sponsored by: Citrix Systems R&D

Modified:
  head/sys/dev/xen/timer/timer.c

Modified: head/sys/dev/xen/timer/timer.c
==============================================================================
--- head/sys/dev/xen/timer/timer.c	Mon May  2 16:14:55 2016	(r298928)
+++ head/sys/dev/xen/timer/timer.c	Mon May  2 16:15:28 2016	(r298929)
@@ -53,6 +53,7 @@ __FBSDID("$FreeBSD$");
 #include <xen/hypervisor.h>
 #include <xen/interface/io/xenbus.h>
 #include <xen/interface/vcpu.h>
+#include <xen/error.h>
 
 #include <machine/cpu.h>
 #include <machine/cpufunc.h>
@@ -63,6 +64,8 @@ __FBSDID("$FreeBSD$");
 
 #include <dev/xen/timer/timer.h>
 
+#include <isa/rtc.h>
+
 #include "clock_if.h"
 
 static devclass_t xentimer_devclass;
@@ -211,11 +214,32 @@ xen_fetch_uptime(struct timespec *ts)
 static int
 xentimer_settime(device_t dev __unused, struct timespec *ts)
 {
+	struct xen_platform_op settime;
+	int ret;
+
 	/*
 	 * Don't return EINVAL here; just silently fail if the domain isn't
 	 * privileged enough to set the TOD.
 	 */
-	return (0);
+	if (!xen_initial_domain())
+		return (0);
+
+	/* Set the native RTC. */
+	atrtc_set(ts);
+
+	settime.cmd = XENPF_settime64;
+	settime.u.settime64.mbz = 0;
+	settime.u.settime64.secs = ts->tv_sec;
+	settime.u.settime64.nsecs = ts->tv_nsec;
+	settime.u.settime64.system_time =
+		xen_fetch_vcpu_time(DPCPU_GET(vcpu_info));
+
+	ret = HYPERVISOR_platform_op(&settime);
+	ret = ret != 0 ? xen_translate_error(ret) : 0;
+	if (ret != 0 && bootverbose)
+		device_printf(dev, "failed to set Xen PV clock: %d\n", ret);
+
+	return (ret);
 }
 
 /**