2
* QEMU KVM support, paravirtual clock device
4
* Copyright (C) 2011 Siemens AG
7
* Jan Kiszka <jan.kiszka@siemens.com>
9
* This work is licensed under the terms of the GNU GPL version 2.
10
* See the COPYING file in the top-level directory.
14
#include "qemu-common.h"
20
#include <linux/kvm.h>
21
#include <linux/kvm_para.h>
23
typedef struct KVMClockState {
29
static void kvmclock_pre_save(void *opaque)
31
KVMClockState *s = opaque;
32
struct kvm_clock_data data;
38
ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
40
fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret));
43
s->clock = data.clock;
45
* If the VM is stopped, declare the clock state valid to avoid re-reading
46
* it on next vmsave (which would return a different value). Will be reset
47
* when the VM is continued.
49
s->clock_valid = !vm_running;
52
static int kvmclock_post_load(void *opaque, int version_id)
54
KVMClockState *s = opaque;
55
struct kvm_clock_data data;
57
data.clock = s->clock;
59
return kvm_vm_ioctl(kvm_state, KVM_SET_CLOCK, &data);
62
static void kvmclock_vm_state_change(void *opaque, int running, int reason)
64
KVMClockState *s = opaque;
67
s->clock_valid = false;
71
static int kvmclock_init(SysBusDevice *dev)
73
KVMClockState *s = FROM_SYSBUS(KVMClockState, dev);
75
qemu_add_vm_change_state_handler(kvmclock_vm_state_change, s);
79
static const VMStateDescription kvmclock_vmsd = {
82
.minimum_version_id = 1,
83
.minimum_version_id_old = 1,
84
.pre_save = kvmclock_pre_save,
85
.post_load = kvmclock_post_load,
86
.fields = (VMStateField[]) {
87
VMSTATE_UINT64(clock, KVMClockState),
92
static SysBusDeviceInfo kvmclock_info = {
93
.qdev.name = "kvmclock",
94
.qdev.size = sizeof(KVMClockState),
95
.qdev.vmsd = &kvmclock_vmsd,
97
.init = kvmclock_init,
100
/* Note: Must be called after VCPU initialization. */
101
void kvmclock_create(void)
104
first_cpu->cpuid_kvm_features & ((1ULL << KVM_FEATURE_CLOCKSOURCE)
105
#ifdef KVM_FEATURE_CLOCKSOURCE2
106
|| (1ULL << KVM_FEATURE_CLOCKSOURCE2)
109
sysbus_create_simple("kvmclock", -1, NULL);
113
static void kvmclock_register_device(void)
116
sysbus_register_withprop(&kvmclock_info);
120
device_init(kvmclock_register_device);