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.
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
16 #include "qemu-common.h"
17 #include "sysemu/sysemu.h"
18 #include "sysemu/kvm.h"
19 #include "hw/sysbus.h"
20 #include "hw/kvm/clock.h"
22 #include <linux/kvm.h>
23 #include <linux/kvm_para.h>
25 #define TYPE_KVM_CLOCK "kvmclock"
26 #define KVM_CLOCK(obj) OBJECT_CHECK(KVMClockState, (obj), TYPE_KVM_CLOCK)
28 typedef struct KVMClockState
{
38 static void kvmclock_vm_state_change(void *opaque
, int running
,
41 KVMClockState
*s
= opaque
;
42 CPUState
*cpu
= first_cpu
;
43 int cap_clock_ctrl
= kvm_check_extension(kvm_state
, KVM_CAP_KVMCLOCK_CTRL
);
47 struct kvm_clock_data data
;
49 s
->clock_valid
= false;
51 data
.clock
= s
->clock
;
53 ret
= kvm_vm_ioctl(kvm_state
, KVM_SET_CLOCK
, &data
);
55 fprintf(stderr
, "KVM_SET_CLOCK failed: %s\n", strerror(ret
));
59 if (!cap_clock_ctrl
) {
62 for (cpu
= first_cpu
; cpu
!= NULL
; cpu
= cpu
->next_cpu
) {
63 ret
= kvm_vcpu_ioctl(cpu
, KVM_KVMCLOCK_CTRL
, 0);
66 fprintf(stderr
, "%s: %s\n", __func__
, strerror(-ret
));
72 struct kvm_clock_data data
;
78 ret
= kvm_vm_ioctl(kvm_state
, KVM_GET_CLOCK
, &data
);
80 fprintf(stderr
, "KVM_GET_CLOCK failed: %s\n", strerror(ret
));
83 s
->clock
= data
.clock
;
86 * If the VM is stopped, declare the clock state valid to
87 * avoid re-reading it on next vmsave (which would return
88 * a different value). Will be reset when the VM is continued.
90 s
->clock_valid
= true;
94 static void kvmclock_realize(DeviceState
*dev
, Error
**errp
)
96 KVMClockState
*s
= KVM_CLOCK(dev
);
98 qemu_add_vm_change_state_handler(kvmclock_vm_state_change
, s
);
101 static const VMStateDescription kvmclock_vmsd
= {
104 .minimum_version_id
= 1,
105 .minimum_version_id_old
= 1,
106 .fields
= (VMStateField
[]) {
107 VMSTATE_UINT64(clock
, KVMClockState
),
108 VMSTATE_END_OF_LIST()
112 static void kvmclock_class_init(ObjectClass
*klass
, void *data
)
114 DeviceClass
*dc
= DEVICE_CLASS(klass
);
116 dc
->realize
= kvmclock_realize
;
118 dc
->vmsd
= &kvmclock_vmsd
;
121 static const TypeInfo kvmclock_info
= {
122 .name
= TYPE_KVM_CLOCK
,
123 .parent
= TYPE_SYS_BUS_DEVICE
,
124 .instance_size
= sizeof(KVMClockState
),
125 .class_init
= kvmclock_class_init
,
128 /* Note: Must be called after VCPU initialization. */
129 void kvmclock_create(void)
131 X86CPU
*cpu
= X86_CPU(first_cpu
);
134 cpu
->env
.features
[FEAT_KVM
] & ((1ULL << KVM_FEATURE_CLOCKSOURCE
) |
135 (1ULL << KVM_FEATURE_CLOCKSOURCE2
))) {
136 sysbus_create_simple(TYPE_KVM_CLOCK
, -1, NULL
);
140 static void kvmclock_register_types(void)
142 type_register_static(&kvmclock_info
);
145 type_init(kvmclock_register_types
)