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-rw-r--r--hw/kvm/clock.c120
-rw-r--r--hw/kvm/clock.h24
2 files changed, 144 insertions, 0 deletions
diff --git a/hw/kvm/clock.c b/hw/kvm/clock.c
new file mode 100644
index 0000000..bb28c08
--- /dev/null
+++ b/hw/kvm/clock.c
@@ -0,0 +1,120 @@
+/*
+ * 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.h"
+#include "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;
+
+ if (running) {
+ s->clock_valid = false;
+ }
+}
+
+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 SysBusDeviceInfo kvmclock_info = {
+ .qdev.name = "kvmclock",
+ .qdev.size = sizeof(KVMClockState),
+ .qdev.vmsd = &kvmclock_vmsd,
+ .qdev.no_user = 1,
+ .init = kvmclock_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_device(void)
+{
+ if (kvm_enabled()) {
+ sysbus_register_withprop(&kvmclock_info);
+ }
+}
+
+device_init(kvmclock_register_device);
diff --git a/hw/kvm/clock.h b/hw/kvm/clock.h
new file mode 100644
index 0000000..252ea13
--- /dev/null
+++ b/hw/kvm/clock.h
@@ -0,0 +1,24 @@
+/*
+ * 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.
+ *
+ */
+
+#ifdef CONFIG_KVM
+
+void kvmclock_create(void);
+
+#else /* CONFIG_KVM */
+
+static inline void kvmclock_create(void)
+{
+}
+
+#endif /* !CONFIG_KVM */