qemu/hw/s390x/event-facility.c
Richard Henderson b9b59a36c3 hw/s390x: Constify VMState
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231221031652.119827-51-richard.henderson@linaro.org>
2023-12-30 07:38:06 +11:00

539 lines
16 KiB
C

/*
* SCLP
* Event Facility
* handles SCLP event types
* - Signal Quiesce - system power down
* - ASCII Console Data - VT220 read and write
*
* Copyright IBM, Corp. 2012
*
* Authors:
* Heinz Graalfs <graalfs@de.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 "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/module.h"
#include "hw/s390x/sclp.h"
#include "migration/vmstate.h"
#include "hw/s390x/event-facility.h"
typedef struct SCLPEventsBus {
BusState qbus;
} SCLPEventsBus;
/* we need to save 32 bit chunks for compatibility */
#if HOST_BIG_ENDIAN
#define RECV_MASK_LOWER 1
#define RECV_MASK_UPPER 0
#else /* little endian host */
#define RECV_MASK_LOWER 0
#define RECV_MASK_UPPER 1
#endif
struct SCLPEventFacility {
SysBusDevice parent_obj;
SCLPEventsBus sbus;
SCLPEvent quiesce, cpu_hotplug;
/* guest's receive mask */
union {
uint32_t receive_mask_pieces[2];
sccb_mask_t receive_mask;
};
/*
* when false, we keep the same broken, backwards compatible behaviour as
* before, allowing only masks of size exactly 4; when true, we implement
* the architecture correctly, allowing all valid mask sizes. Needed for
* migration toward older versions.
*/
bool allow_all_mask_sizes;
/* length of the receive mask */
uint16_t mask_length;
};
/* return true if any child has event pending set */
static bool event_pending(SCLPEventFacility *ef)
{
BusChild *kid;
SCLPEvent *event;
SCLPEventClass *event_class;
QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
event = SCLP_EVENT(kid->child);
event_class = SCLP_EVENT_GET_CLASS(event);
if (event->event_pending &&
event_class->get_send_mask() & ef->receive_mask) {
return true;
}
}
return false;
}
static sccb_mask_t get_host_send_mask(SCLPEventFacility *ef)
{
sccb_mask_t mask;
BusChild *kid;
SCLPEventClass *child;
mask = 0;
QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
DeviceState *qdev = kid->child;
child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev);
mask |= child->get_send_mask();
}
return mask;
}
static sccb_mask_t get_host_receive_mask(SCLPEventFacility *ef)
{
sccb_mask_t mask;
BusChild *kid;
SCLPEventClass *child;
mask = 0;
QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
DeviceState *qdev = kid->child;
child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev);
mask |= child->get_receive_mask();
}
return mask;
}
static uint16_t write_event_length_check(SCCB *sccb)
{
int slen;
unsigned elen = 0;
EventBufferHeader *event;
WriteEventData *wed = (WriteEventData *) sccb;
event = (EventBufferHeader *) &wed->ebh;
for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) {
elen = be16_to_cpu(event->length);
if (elen < sizeof(*event) || elen > slen) {
return SCLP_RC_EVENT_BUFFER_SYNTAX_ERROR;
}
event = (void *) event + elen;
}
if (slen) {
return SCLP_RC_INCONSISTENT_LENGTHS;
}
return SCLP_RC_NORMAL_COMPLETION;
}
static uint16_t handle_write_event_buf(SCLPEventFacility *ef,
EventBufferHeader *event_buf, SCCB *sccb)
{
uint16_t rc;
BusChild *kid;
SCLPEvent *event;
SCLPEventClass *ec;
rc = SCLP_RC_INVALID_FUNCTION;
QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
DeviceState *qdev = kid->child;
event = (SCLPEvent *) qdev;
ec = SCLP_EVENT_GET_CLASS(event);
if (ec->write_event_data &&
ec->can_handle_event(event_buf->type)) {
rc = ec->write_event_data(event, event_buf);
break;
}
}
return rc;
}
static uint16_t handle_sccb_write_events(SCLPEventFacility *ef, SCCB *sccb)
{
uint16_t rc;
int slen;
unsigned elen = 0;
EventBufferHeader *event_buf;
WriteEventData *wed = (WriteEventData *) sccb;
event_buf = &wed->ebh;
rc = SCLP_RC_NORMAL_COMPLETION;
/* loop over all contained event buffers */
for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) {
elen = be16_to_cpu(event_buf->length);
/* in case of a previous error mark all trailing buffers
* as not accepted */
if (rc != SCLP_RC_NORMAL_COMPLETION) {
event_buf->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED);
} else {
rc = handle_write_event_buf(ef, event_buf, sccb);
}
event_buf = (void *) event_buf + elen;
}
return rc;
}
static void write_event_data(SCLPEventFacility *ef, SCCB *sccb)
{
if (sccb->h.function_code != SCLP_FC_NORMAL_WRITE) {
sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION);
return;
}
if (be16_to_cpu(sccb->h.length) < 8) {
sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
return;
}
/* first do a sanity check of the write events */
sccb->h.response_code = cpu_to_be16(write_event_length_check(sccb));
/* if no early error, then execute */
if (sccb->h.response_code == be16_to_cpu(SCLP_RC_NORMAL_COMPLETION)) {
sccb->h.response_code =
cpu_to_be16(handle_sccb_write_events(ef, sccb));
}
}
static uint16_t handle_sccb_read_events(SCLPEventFacility *ef, SCCB *sccb,
sccb_mask_t mask)
{
uint16_t rc;
int slen;
unsigned elen;
BusChild *kid;
SCLPEvent *event;
SCLPEventClass *ec;
EventBufferHeader *event_buf;
ReadEventData *red = (ReadEventData *) sccb;
event_buf = &red->ebh;
event_buf->length = 0;
slen = sccb_data_len(sccb);
rc = SCLP_RC_NO_EVENT_BUFFERS_STORED;
QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
DeviceState *qdev = kid->child;
event = (SCLPEvent *) qdev;
ec = SCLP_EVENT_GET_CLASS(event);
if (mask & ec->get_send_mask()) {
if (ec->read_event_data(event, event_buf, &slen)) {
elen = be16_to_cpu(event_buf->length);
event_buf = (EventBufferHeader *) ((char *)event_buf + elen);
rc = SCLP_RC_NORMAL_COMPLETION;
}
}
}
if (sccb->h.control_mask[2] & SCLP_VARIABLE_LENGTH_RESPONSE) {
/* architecture suggests to reset variable-length-response bit */
sccb->h.control_mask[2] &= ~SCLP_VARIABLE_LENGTH_RESPONSE;
/* with a new length value */
sccb->h.length = cpu_to_be16(SCCB_SIZE - slen);
}
return rc;
}
/* copy up to src_len bytes and fill the rest of dst with zeroes */
static void copy_mask(uint8_t *dst, uint8_t *src, uint16_t dst_len,
uint16_t src_len)
{
int i;
for (i = 0; i < dst_len; i++) {
dst[i] = i < src_len ? src[i] : 0;
}
}
static void read_event_data(SCLPEventFacility *ef, SCCB *sccb)
{
sccb_mask_t sclp_active_selection_mask;
sccb_mask_t sclp_cp_receive_mask;
ReadEventData *red = (ReadEventData *) sccb;
if (be16_to_cpu(sccb->h.length) != SCCB_SIZE) {
sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
return;
}
switch (sccb->h.function_code) {
case SCLP_UNCONDITIONAL_READ:
sccb->h.response_code = cpu_to_be16(
handle_sccb_read_events(ef, sccb, ef->receive_mask));
break;
case SCLP_SELECTIVE_READ:
/* get active selection mask */
sclp_cp_receive_mask = ef->receive_mask;
copy_mask((uint8_t *)&sclp_active_selection_mask, (uint8_t *)&red->mask,
sizeof(sclp_active_selection_mask), ef->mask_length);
sclp_active_selection_mask = be64_to_cpu(sclp_active_selection_mask);
if (!sclp_cp_receive_mask ||
(sclp_active_selection_mask & ~sclp_cp_receive_mask)) {
sccb->h.response_code =
cpu_to_be16(SCLP_RC_INVALID_SELECTION_MASK);
} else {
sccb->h.response_code = cpu_to_be16(
handle_sccb_read_events(ef, sccb, sclp_active_selection_mask));
}
break;
default:
sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION);
}
}
static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb)
{
WriteEventMask *we_mask = (WriteEventMask *) sccb;
uint16_t mask_length = be16_to_cpu(we_mask->mask_length);
sccb_mask_t tmp_mask;
if (!mask_length || (mask_length > SCLP_EVENT_MASK_LEN_MAX) ||
((mask_length != 4) && !ef->allow_all_mask_sizes)) {
sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_MASK_LENGTH);
return;
}
/*
* Note: We currently only support masks up to 8 byte length;
* the remainder is filled up with zeroes. Older Linux
* kernels use a 4 byte mask length, newer ones can use both
* 8 or 4 depending on what is available on the host.
*/
/* keep track of the guest's capability masks */
copy_mask((uint8_t *)&tmp_mask, WEM_CP_RECEIVE_MASK(we_mask, mask_length),
sizeof(tmp_mask), mask_length);
ef->receive_mask = be64_to_cpu(tmp_mask);
/* return the SCLP's capability masks to the guest */
tmp_mask = cpu_to_be64(get_host_receive_mask(ef));
copy_mask(WEM_RECEIVE_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask,
mask_length, sizeof(tmp_mask));
tmp_mask = cpu_to_be64(get_host_send_mask(ef));
copy_mask(WEM_SEND_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask,
mask_length, sizeof(tmp_mask));
sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_COMPLETION);
ef->mask_length = mask_length;
}
/* qemu object creation and initialization functions */
#define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus"
static const TypeInfo sclp_events_bus_info = {
.name = TYPE_SCLP_EVENTS_BUS,
.parent = TYPE_BUS,
};
static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code)
{
switch (code & SCLP_CMD_CODE_MASK) {
case SCLP_CMD_READ_EVENT_DATA:
read_event_data(ef, sccb);
break;
case SCLP_CMD_WRITE_EVENT_DATA:
write_event_data(ef, sccb);
break;
case SCLP_CMD_WRITE_EVENT_MASK:
write_event_mask(ef, sccb);
break;
}
}
static bool vmstate_event_facility_mask64_needed(void *opaque)
{
SCLPEventFacility *ef = opaque;
return (ef->receive_mask & 0xFFFFFFFF) != 0;
}
static bool vmstate_event_facility_mask_length_needed(void *opaque)
{
SCLPEventFacility *ef = opaque;
return ef->allow_all_mask_sizes;
}
static const VMStateDescription vmstate_event_facility_mask64 = {
.name = "vmstate-event-facility/mask64",
.version_id = 0,
.minimum_version_id = 0,
.needed = vmstate_event_facility_mask64_needed,
.fields = (const VMStateField[]) {
VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_LOWER], SCLPEventFacility),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_event_facility_mask_length = {
.name = "vmstate-event-facility/mask_length",
.version_id = 0,
.minimum_version_id = 0,
.needed = vmstate_event_facility_mask_length_needed,
.fields = (const VMStateField[]) {
VMSTATE_UINT16(mask_length, SCLPEventFacility),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_event_facility = {
.name = "vmstate-event-facility",
.version_id = 0,
.minimum_version_id = 0,
.fields = (const VMStateField[]) {
VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_UPPER], SCLPEventFacility),
VMSTATE_END_OF_LIST()
},
.subsections = (const VMStateDescription * const []) {
&vmstate_event_facility_mask64,
&vmstate_event_facility_mask_length,
NULL
}
};
static void sclp_event_set_allow_all_mask_sizes(Object *obj, bool value,
Error **errp)
{
SCLPEventFacility *ef = (SCLPEventFacility *)obj;
ef->allow_all_mask_sizes = value;
}
static bool sclp_event_get_allow_all_mask_sizes(Object *obj, Error **errp)
{
SCLPEventFacility *ef = (SCLPEventFacility *)obj;
return ef->allow_all_mask_sizes;
}
static void init_event_facility(Object *obj)
{
SCLPEventFacility *event_facility = EVENT_FACILITY(obj);
DeviceState *sdev = DEVICE(obj);
event_facility->mask_length = 4;
event_facility->allow_all_mask_sizes = true;
object_property_add_bool(obj, "allow_all_mask_sizes",
sclp_event_get_allow_all_mask_sizes,
sclp_event_set_allow_all_mask_sizes);
/* Spawn a new bus for SCLP events */
qbus_init(&event_facility->sbus, sizeof(event_facility->sbus),
TYPE_SCLP_EVENTS_BUS, sdev, NULL);
object_initialize_child(obj, TYPE_SCLP_QUIESCE,
&event_facility->quiesce,
TYPE_SCLP_QUIESCE);
object_initialize_child(obj, TYPE_SCLP_CPU_HOTPLUG,
&event_facility->cpu_hotplug,
TYPE_SCLP_CPU_HOTPLUG);
}
static void realize_event_facility(DeviceState *dev, Error **errp)
{
SCLPEventFacility *event_facility = EVENT_FACILITY(dev);
if (!qdev_realize(DEVICE(&event_facility->quiesce),
BUS(&event_facility->sbus), errp)) {
return;
}
if (!qdev_realize(DEVICE(&event_facility->cpu_hotplug),
BUS(&event_facility->sbus), errp)) {
qdev_unrealize(DEVICE(&event_facility->quiesce));
return;
}
}
static void reset_event_facility(DeviceState *dev)
{
SCLPEventFacility *sdev = EVENT_FACILITY(dev);
sdev->receive_mask = 0;
}
static void init_event_facility_class(ObjectClass *klass, void *data)
{
SysBusDeviceClass *sbdc = SYS_BUS_DEVICE_CLASS(klass);
DeviceClass *dc = DEVICE_CLASS(sbdc);
SCLPEventFacilityClass *k = EVENT_FACILITY_CLASS(dc);
dc->realize = realize_event_facility;
dc->reset = reset_event_facility;
dc->vmsd = &vmstate_event_facility;
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
k->command_handler = command_handler;
k->event_pending = event_pending;
}
static const TypeInfo sclp_event_facility_info = {
.name = TYPE_SCLP_EVENT_FACILITY,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_init = init_event_facility,
.instance_size = sizeof(SCLPEventFacility),
.class_init = init_event_facility_class,
.class_size = sizeof(SCLPEventFacilityClass),
};
static void event_realize(DeviceState *qdev, Error **errp)
{
SCLPEvent *event = SCLP_EVENT(qdev);
SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event);
if (child->init) {
int rc = child->init(event);
if (rc < 0) {
error_setg(errp, "SCLP event initialization failed.");
return;
}
}
}
static void event_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->bus_type = TYPE_SCLP_EVENTS_BUS;
dc->realize = event_realize;
}
static const TypeInfo sclp_event_type_info = {
.name = TYPE_SCLP_EVENT,
.parent = TYPE_DEVICE,
.instance_size = sizeof(SCLPEvent),
.class_init = event_class_init,
.class_size = sizeof(SCLPEventClass),
.abstract = true,
};
static void register_types(void)
{
type_register_static(&sclp_events_bus_info);
type_register_static(&sclp_event_facility_info);
type_register_static(&sclp_event_type_info);
}
type_init(register_types)
BusState *sclp_get_event_facility_bus(void)
{
Object *busobj;
SCLPEventsBus *sbus;
busobj = object_resolve_path_type("", TYPE_SCLP_EVENTS_BUS, NULL);
sbus = OBJECT_CHECK(SCLPEventsBus, busobj, TYPE_SCLP_EVENTS_BUS);
if (!sbus) {
return NULL;
}
return &sbus->qbus;
}