On 24/01/2020 23.14, Collin Walling wrote:
> DIAGNOSE 0x318 (diag318) is a privileged s390x instruction that must
> be intercepted by SIE and handled via KVM. Let's introduce some
> functions to communicate between QEMU and KVM via ioctls. These
> will be used to get/set the diag318 information.
>
> The availability of this instruction is determined by byte 134, bit 0
> of the Read Info block. This coincidentally expands into the space used
> for CPU entries by taking away one byte, which means VMs running with
> the diag318 capability will not be able to retrieve information regarding
> the 248th CPU. This will not effect performance, and VMs can still be
s/effect/affect/ ?
> ran with 248 CPUs.
s/ran/run/ ?
> In order to simplify the migration and system reset requirements of
> the diag318 data, let's introduce it as a device class and include
> a VMStateDescription.
>
> Diag318 is set to 0 during modified clear and load normal resets.
>
> Signed-off-by: Collin Walling <wall...@linux.ibm.com>
> ---
> hw/s390x/Makefile.objs | 1 +
> hw/s390x/diag318.c | 85
> +++++++++++++++++++++++++++++++++++++
> hw/s390x/diag318.h | 40 +++++++++++++++++
> hw/s390x/s390-virtio-ccw.c | 17 ++++++++
> hw/s390x/sclp.c | 13 ++++++
> include/hw/s390x/sclp.h | 2 +
> target/s390x/cpu_features.h | 1 +
> target/s390x/cpu_features_def.inc.h | 3 ++
> target/s390x/gen-features.c | 1 +
> target/s390x/kvm-stub.c | 10 +++++
> target/s390x/kvm.c | 29 +++++++++++++
> target/s390x/kvm_s390x.h | 2 +
> 12 files changed, 204 insertions(+)
> create mode 100644 hw/s390x/diag318.c
> create mode 100644 hw/s390x/diag318.h
>
> diff --git a/hw/s390x/Makefile.objs b/hw/s390x/Makefile.objs
> index e02ed80..93621dc 100644
> --- a/hw/s390x/Makefile.objs
> +++ b/hw/s390x/Makefile.objs
> @@ -34,3 +34,4 @@ obj-$(CONFIG_KVM) += s390-stattrib-kvm.o
> obj-y += s390-ccw.o
> obj-y += ap-device.o
> obj-y += ap-bridge.o
> +obj-y += diag318.o
> diff --git a/hw/s390x/diag318.c b/hw/s390x/diag318.c
> new file mode 100644
> index 0000000..2d30bb2
> --- /dev/null
> +++ b/hw/s390x/diag318.c
> @@ -0,0 +1,85 @@
> +/*
> + * DIAGNOSE 0x318 functions for reset and migration
> + *
> + * Copyright IBM, Corp. 2019
Bump to 2020 ?
> + * Authors:
> + * Collin Walling <wall...@linux.ibm.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or (at
> your
> + * option) any later version. See the COPYING file in the top-level
> directory.
> + */
> +
> +#include "hw/s390x/diag318.h"
> +#include "qapi/error.h"
> +#include "kvm_s390x.h"
> +#include "sysemu/kvm.h"
> +
> +static int diag318_post_load(void *opaque, int version_id)
> +{
> + DIAG318State *d = opaque;
> +
> + if (kvm_enabled())
> + kvm_s390_set_diag318_info(d->info);
QEMU coding style requires curly braces also for single lines.
> + return 0;
> +}
> +
> +static int diag318_pre_save(void *opaque)
> +{
> + DIAG318State *d = opaque;
> +
> + if (kvm_enabled())
> + kvm_s390_get_diag318_info(&d->info);
dito
> + return 0;
> +}
> +
> +static bool diag318_needed(void *opaque)
> +{
> + return kvm_enabled() ? s390_has_feat(S390_FEAT_DIAG318) : 0;
> +}
> +
> +const VMStateDescription vmstate_diag318 = {
> + .name = "vmstate_diag318",
> + .post_load = diag318_post_load,
> + .pre_save = diag318_pre_save,
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .needed = diag318_needed,
> + .fields = (VMStateField[]) {
> + VMSTATE_UINT64(info, DIAG318State),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> +static void s390_diag318_reset(DeviceState *dev)
> +{
> + if (kvm_enabled())
> + kvm_s390_set_diag318_info(0);
dito
> +}
> +
> +static void s390_diag318_class_init(ObjectClass *klass, void *data)
> +{
> + DeviceClass *dc = DEVICE_CLASS(klass);
> +
> + dc->reset = s390_diag318_reset;
> + dc->vmsd = &vmstate_diag318;
> + dc->hotpluggable = false;
> + /* Reason: Created automatically during machine instantiation */
> + dc->user_creatable = false;
> +}
> +
> +static const TypeInfo s390_diag318_info = {
> + .class_init = s390_diag318_class_init,
> + .parent = TYPE_DEVICE,
> + .name = TYPE_S390_DIAG318,
> + .instance_size = sizeof(DIAG318State),
> +};
> +
> +static void s390_diag318_register_types(void)
> +{
> + type_register_static(&s390_diag318_info);
> +}
> +
> +type_init(s390_diag318_register_types)
> diff --git a/hw/s390x/diag318.h b/hw/s390x/diag318.h
> new file mode 100644
> index 0000000..06d9f67
> --- /dev/null
> +++ b/hw/s390x/diag318.h
> @@ -0,0 +1,40 @@
> +/*
> + * DIAGNOSE 0x318 functions for reset and migration
> + *
> + * Copyright IBM, Corp. 2019
2020 ?
> + * Authors:
> + * Collin Walling <wall...@linux.ibm.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or (at
> your
> + * option) any later version. See the COPYING file in the top-level
> directory.
> + */
> +
> +#ifndef HW_DIAG318_H
> +#define HW_DIAG318_H
> +
> +#include "qemu/osdep.h"
> +#include "migration/vmstate.h"
> +#include "qom/object.h"
> +#include "hw/qdev-core.h"
> +
> +#define TYPE_S390_DIAG318 "diag318"
> +#define DIAG318(obj) \
> + OBJECT_CHECK(DIAG318State, (obj), TYPE_S390_DIAG318)
> +
> +typedef struct DIAG318State {
> + /*< private >*/
> + DeviceState parent_obj;
> +
> + /*< public >*/
> + uint64_t info;
> +} DIAG318State;
> +
> +typedef struct DIAG318Class {
> + /*< private >*/
> + DeviceClass parent_class;
> +
> + /*< public >*/
> +} DIAG318Class;
You don't use DIAG318Class anywhere. Please drop it.
> +#endif /* HW_DIAG318_H */
> \ No newline at end of file
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index e0e2813..d5b7a33 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -41,6 +41,7 @@
> #include "hw/qdev-properties.h"
> #include "hw/s390x/tod.h"
> #include "sysemu/sysemu.h"
> +#include "hw/s390x/diag318.h"
>
> S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
> {
> @@ -97,6 +98,7 @@ static const char *const reset_dev_types[] = {
> "s390-sclp-event-facility",
> "s390-flic",
> "diag288",
> + TYPE_S390_DIAG318,
> };
>
> static void subsystem_reset(void)
> @@ -237,6 +239,17 @@ static void s390_create_sclpconsole(const char *type,
> Chardev *chardev)
> qdev_init_nofail(dev);
> }
>
> +static void s390_init_diag318(void)
> +{
> + Object *new = object_new(TYPE_S390_DIAG318);
For the very unlikely case that we ever switch QEMU to C++ ... could you
maybe use a different variable name than "new" ? Simply "obj" maybe?
> + DeviceState *dev = DEVICE(new);
> +
> + object_property_add_child(qdev_get_machine(), TYPE_S390_DIAG318,
> + new, NULL);
> + object_unref(new);
> + qdev_init_nofail(dev);
> +}
> +
Thomas
