1 files changed, 143 insertions, 0 deletions
diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c
new file mode 100644
index 0000000000..fa40e283f7
--- /dev/null
+++ b/hw/i386/kvm/clock.c
@@ -0,0 +1,143 @@
+/*
+ * 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(ENV_GET_CPU(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 const 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)