qemu

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/*
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 * TOD (Time Of Day) clock
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 *
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 * Copyright 2018 Red Hat, Inc.
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 * Author(s): David Hildenbrand <david@redhat.com>
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2 or later.
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 * See the COPYING file in the top-level directory.
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 */
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#include "qemu/osdep.h"
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#include "hw/s390x/tod.h"
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#include "qapi/error.h"
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#include "qemu/error-report.h"
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#include "qemu/module.h"
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#include "sysemu/kvm.h"
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#include "sysemu/tcg.h"
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#include "sysemu/qtest.h"
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#include "migration/qemu-file-types.h"
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#include "migration/register.h"
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void s390_init_tod(void)
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{
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    Object *obj;
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    if (kvm_enabled()) {
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        obj = object_new(TYPE_KVM_S390_TOD);
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    } else if (tcg_enabled()) {
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        obj = object_new(TYPE_QEMU_S390_TOD);
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    } else if (qtest_enabled()) {
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        return;
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    } else {
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        error_report("current accelerator not handled in s390_init_tod!");
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        abort();
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    }
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    object_property_add_child(qdev_get_machine(), TYPE_S390_TOD, obj);
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    object_unref(obj);
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    qdev_realize(DEVICE(obj), NULL, &error_fatal);
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}
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S390TODState *s390_get_todstate(void)
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{
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    static S390TODState *ts;
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    if (!ts) {
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        ts = S390_TOD(object_resolve_path_type("", TYPE_S390_TOD, NULL));
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    }
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    return ts;
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}
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#define S390_TOD_CLOCK_VALUE_MISSING    0x00
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#define S390_TOD_CLOCK_VALUE_PRESENT    0x01
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static void s390_tod_save(QEMUFile *f, void *opaque)
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{
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    S390TODState *td = opaque;
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    S390TODClass *tdc = S390_TOD_GET_CLASS(td);
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    Error *err = NULL;
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    S390TOD tod;
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    tdc->get(td, &tod, &err);
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    if (err) {
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        warn_report_err(err);
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        error_printf("Guest clock will not be migrated "
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                     "which could cause the guest to hang.");
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        qemu_put_byte(f, S390_TOD_CLOCK_VALUE_MISSING);
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        return;
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    }
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    qemu_put_byte(f, S390_TOD_CLOCK_VALUE_PRESENT);
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    qemu_put_byte(f, tod.high);
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    qemu_put_be64(f, tod.low);
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}
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static int s390_tod_load(QEMUFile *f, void *opaque, int version_id)
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{
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    S390TODState *td = opaque;
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    S390TODClass *tdc = S390_TOD_GET_CLASS(td);
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    Error *err = NULL;
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    S390TOD tod;
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    if (qemu_get_byte(f) == S390_TOD_CLOCK_VALUE_MISSING) {
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        warn_report("Guest clock was not migrated. This could "
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                    "cause the guest to hang.");
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        return 0;
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    }
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    tod.high = qemu_get_byte(f);
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    tod.low = qemu_get_be64(f);
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    tdc->set(td, &tod, &err);
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    if (err) {
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        error_report_err(err);
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        return -1;
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    }
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    return 0;
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}
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static SaveVMHandlers savevm_tod = {
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    .save_state = s390_tod_save,
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    .load_state = s390_tod_load,
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};
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static void s390_tod_realize(DeviceState *dev, Error **errp)
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{
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    S390TODState *td = S390_TOD(dev);
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    /* Legacy migration interface */
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    register_savevm_live("todclock", 0, 1, &savevm_tod, td);
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}
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static void s390_tod_class_init(ObjectClass *oc, void *data)
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{
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    DeviceClass *dc = DEVICE_CLASS(oc);
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    dc->desc = "TOD (Time Of Day) Clock";
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    dc->realize = s390_tod_realize;
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    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
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    /* We only have one TOD clock in the system attached to the machine */
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    dc->user_creatable = false;
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}
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static const TypeInfo s390_tod_info = {
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    .name = TYPE_S390_TOD,
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    .parent = TYPE_DEVICE,
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    .instance_size = sizeof(S390TODState),
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    .class_init = s390_tod_class_init,
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    .class_size = sizeof(S390TODClass),
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    .abstract = true,
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};
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static void register_types(void)
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{
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    type_register_static(&s390_tod_info);
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}
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type_init(register_types);
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