Add access control support to qemu bridge helper
[qemu.git] / hw / kvm / clock.c
1 /*
2 * QEMU KVM support, paravirtual clock device
3 *
4 * Copyright (C) 2011 Siemens AG
5 *
6 * Authors:
7 * Jan Kiszka <jan.kiszka@siemens.com>
8 *
9 * This work is licensed under the terms of the GNU GPL version 2.
10 * See the COPYING file in the top-level directory.
11 *
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.
14 */
15
16 #include "qemu-common.h"
17 #include "sysemu.h"
18 #include "kvm.h"
19 #include "hw/sysbus.h"
20 #include "hw/kvm/clock.h"
21
22 #include <linux/kvm.h>
23 #include <linux/kvm_para.h>
24
25 typedef struct KVMClockState {
26 SysBusDevice busdev;
27 uint64_t clock;
28 bool clock_valid;
29 } KVMClockState;
30
31 static void kvmclock_pre_save(void *opaque)
32 {
33 KVMClockState *s = opaque;
34 struct kvm_clock_data data;
35 int ret;
36
37 if (s->clock_valid) {
38 return;
39 }
40 ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
41 if (ret < 0) {
42 fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret));
43 data.clock = 0;
44 }
45 s->clock = data.clock;
46 /*
47 * If the VM is stopped, declare the clock state valid to avoid re-reading
48 * it on next vmsave (which would return a different value). Will be reset
49 * when the VM is continued.
50 */
51 s->clock_valid = !runstate_is_running();
52 }
53
54 static int kvmclock_post_load(void *opaque, int version_id)
55 {
56 KVMClockState *s = opaque;
57 struct kvm_clock_data data;
58
59 data.clock = s->clock;
60 data.flags = 0;
61 return kvm_vm_ioctl(kvm_state, KVM_SET_CLOCK, &data);
62 }
63
64 static void kvmclock_vm_state_change(void *opaque, int running,
65 RunState state)
66 {
67 KVMClockState *s = opaque;
68
69 if (running) {
70 s->clock_valid = false;
71 }
72 }
73
74 static int kvmclock_init(SysBusDevice *dev)
75 {
76 KVMClockState *s = FROM_SYSBUS(KVMClockState, dev);
77
78 qemu_add_vm_change_state_handler(kvmclock_vm_state_change, s);
79 return 0;
80 }
81
82 static const VMStateDescription kvmclock_vmsd = {
83 .name = "kvmclock",
84 .version_id = 1,
85 .minimum_version_id = 1,
86 .minimum_version_id_old = 1,
87 .pre_save = kvmclock_pre_save,
88 .post_load = kvmclock_post_load,
89 .fields = (VMStateField[]) {
90 VMSTATE_UINT64(clock, KVMClockState),
91 VMSTATE_END_OF_LIST()
92 }
93 };
94
95 static void kvmclock_class_init(ObjectClass *klass, void *data)
96 {
97 SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
98
99 k->init = kvmclock_init;
100 }
101
102 static DeviceInfo kvmclock_info = {
103 .name = "kvmclock",
104 .size = sizeof(KVMClockState),
105 .vmsd = &kvmclock_vmsd,
106 .no_user = 1,
107 .class_init = kvmclock_class_init,
108 };
109
110 /* Note: Must be called after VCPU initialization. */
111 void kvmclock_create(void)
112 {
113 if (kvm_enabled() &&
114 first_cpu->cpuid_kvm_features & ((1ULL << KVM_FEATURE_CLOCKSOURCE) |
115 (1ULL << KVM_FEATURE_CLOCKSOURCE2))) {
116 sysbus_create_simple("kvmclock", -1, NULL);
117 }
118 }
119
120 static void kvmclock_register_device(void)
121 {
122 if (kvm_enabled()) {
123 sysbus_register_withprop(&kvmclock_info);
124 }
125 }
126
127 device_init(kvmclock_register_device);