| /* |
| * QEMU KVM support, paravirtual clock device |
| * |
| * Copyright (C) 2011 Siemens AG |
| * |
| * Authors: |
| * Jan Kiszka <jan.kiszka@siemens.com> |
| * |
| * This work is licensed under the terms of the GNU GPL version 2. |
| * See the COPYING file in the top-level directory. |
| * |
| * Contributions after 2012-01-13 are licensed under the terms of the |
| * GNU GPL, version 2 or (at your option) any later version. |
| */ |
| |
| #include "qemu-common.h" |
| #include "sysemu/sysemu.h" |
| #include "sysemu/kvm.h" |
| #include "hw/sysbus.h" |
| #include "hw/kvm/clock.h" |
| |
| #include <linux/kvm.h> |
| #include <linux/kvm_para.h> |
| |
| typedef struct KVMClockState { |
| SysBusDevice busdev; |
| uint64_t clock; |
| bool clock_valid; |
| } KVMClockState; |
| |
| static void kvmclock_pre_save(void *opaque) |
| { |
| KVMClockState *s = opaque; |
| struct kvm_clock_data data; |
| int ret; |
| |
| if (s->clock_valid) { |
| return; |
| } |
| ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data); |
| if (ret < 0) { |
| fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret)); |
| data.clock = 0; |
| } |
| s->clock = data.clock; |
| /* |
| * If the VM is stopped, declare the clock state valid to avoid re-reading |
| * it on next vmsave (which would return a different value). Will be reset |
| * when the VM is continued. |
| */ |
| s->clock_valid = !runstate_is_running(); |
| } |
| |
| static int kvmclock_post_load(void *opaque, int version_id) |
| { |
| KVMClockState *s = opaque; |
| struct kvm_clock_data data; |
| |
| data.clock = s->clock; |
| data.flags = 0; |
| return kvm_vm_ioctl(kvm_state, KVM_SET_CLOCK, &data); |
| } |
| |
| static void kvmclock_vm_state_change(void *opaque, int running, |
| RunState state) |
| { |
| KVMClockState *s = opaque; |
| CPUArchState *penv = first_cpu; |
| int cap_clock_ctrl = kvm_check_extension(kvm_state, KVM_CAP_KVMCLOCK_CTRL); |
| int ret; |
| |
| if (running) { |
| s->clock_valid = false; |
| |
| if (!cap_clock_ctrl) { |
| return; |
| } |
| for (penv = first_cpu; penv != NULL; penv = penv->next_cpu) { |
| ret = kvm_vcpu_ioctl(penv, KVM_KVMCLOCK_CTRL, 0); |
| if (ret) { |
| if (ret != -EINVAL) { |
| fprintf(stderr, "%s: %s\n", __func__, strerror(-ret)); |
| } |
| return; |
| } |
| } |
| } |
| } |
| |
| static int kvmclock_init(SysBusDevice *dev) |
| { |
| KVMClockState *s = FROM_SYSBUS(KVMClockState, dev); |
| |
| qemu_add_vm_change_state_handler(kvmclock_vm_state_change, s); |
| return 0; |
| } |
| |
| static const VMStateDescription kvmclock_vmsd = { |
| .name = "kvmclock", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .minimum_version_id_old = 1, |
| .pre_save = kvmclock_pre_save, |
| .post_load = kvmclock_post_load, |
| .fields = (VMStateField[]) { |
| VMSTATE_UINT64(clock, KVMClockState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static void kvmclock_class_init(ObjectClass *klass, void *data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); |
| |
| k->init = kvmclock_init; |
| dc->no_user = 1; |
| dc->vmsd = &kvmclock_vmsd; |
| } |
| |
| static TypeInfo kvmclock_info = { |
| .name = "kvmclock", |
| .parent = TYPE_SYS_BUS_DEVICE, |
| .instance_size = sizeof(KVMClockState), |
| .class_init = kvmclock_class_init, |
| }; |
| |
| /* Note: Must be called after VCPU initialization. */ |
| void kvmclock_create(void) |
| { |
| if (kvm_enabled() && |
| first_cpu->cpuid_kvm_features & ((1ULL << KVM_FEATURE_CLOCKSOURCE) | |
| (1ULL << KVM_FEATURE_CLOCKSOURCE2))) { |
| sysbus_create_simple("kvmclock", -1, NULL); |
| } |
| } |
| |
| static void kvmclock_register_types(void) |
| { |
| type_register_static(&kvmclock_info); |
| } |
| |
| type_init(kvmclock_register_types) |