/*
* QEMU S390x KVM floating interrupt controller (flic)
*
* Copyright 2014 IBM Corp.
* Author(s): Jens Freimann <jfrei@linux.vnet.ibm.com>
* Cornelia Huck <cornelia.huck@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 "qemu-common.h"
#include "cpu.h"
#include <sys/ioctl.h>
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "hw/sysbus.h"
#include "sysemu/kvm.h"
#include "hw/s390x/s390_flic.h"
#include "hw/s390x/adapter.h"
#include "hw/s390x/css.h"
#include "trace.h"
#define FLIC_SAVE_INITIAL_SIZE getpagesize()
#define FLIC_FAILED (-1UL)
#define FLIC_SAVEVM_VERSION 1
typedef struct KVMS390FLICState {
S390FLICState parent_obj;
uint32_t fd;
bool clear_io_supported;
} KVMS390FLICState;
DeviceState *s390_flic_kvm_create(void)
{
DeviceState *dev = NULL;
if (kvm_enabled()) {
dev = qdev_create(NULL, TYPE_KVM_S390_FLIC);
object_property_add_child(qdev_get_machine(), TYPE_KVM_S390_FLIC,
OBJECT(dev), NULL);
}
return dev;
}
/**
* flic_get_all_irqs - store all pending irqs in buffer
* @buf: pointer to buffer which is passed to kernel
* @len: length of buffer
* @flic: pointer to flic device state
*
* Returns: -ENOMEM if buffer is too small,
* -EINVAL if attr.group is invalid,
* -EFAULT if copying to userspace failed,
* on success return number of stored interrupts
*/
static int flic_get_all_irqs(KVMS390FLICState *flic,
void *buf, int len)
{
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_GET_ALL_IRQS,
.addr = (uint64_t) buf,
.attr = len,
};
int rc;
rc = ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr);
return rc == -1 ? -errno : rc;
}
static void flic_enable_pfault(KVMS390FLICState *flic)
{
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_APF_ENABLE,
};
int rc;
rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
if (rc) {
fprintf(stderr, "flic: couldn't enable pfault\n");
}
}
static void flic_disable_wait_pfault(KVMS390FLICState *flic)
{
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_APF_DISABLE_WAIT,
};
int rc;
rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
if (rc) {
fprintf(stderr, "flic: couldn't disable pfault\n");
}
}
/** flic_enqueue_irqs - returns 0 on success
* @buf: pointer to buffer which is passed to kernel
* @len: length of buffer
* @flic: pointer to flic device state
*
* Returns: -EINVAL if attr.group is unknown
*/
static int flic_enqueue_irqs(void *buf, uint64_t len,
KVMS390FLICState *flic)
{
int rc;
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_ENQUEUE,
.addr = (uint64_t) buf,
.attr = len,
};
rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
return rc ? -errno : 0;
}
int kvm_s390_inject_flic(struct kvm_s390_irq *irq)
{
static KVMS390FLICState *flic;
if (unlikely(!flic)) {
flic = KVM_S390_FLIC(s390_get_flic());
}
return flic_enqueue_irqs(irq, sizeof(*irq), flic);
}
static int kvm_s390_clear_io_flic(S390FLICState *fs, uint16_t subchannel_id,
uint16_t subchannel_nr)
{
KVMS390FLICState *flic = KVM_S390_FLIC(fs);
int rc;
uint32_t sid = subchannel_id << 16 | subchannel_nr;
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_CLEAR_IO_IRQ,
.addr = (uint64_t) &sid,
.attr = sizeof(sid),
};
if (unlikely(!flic->clear_io_supported)) {
return -ENOSYS;
}
rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
return rc ? -errno : 0;
}
static int kvm_s390_modify_ais_mode(S390FLICState *fs, uint8_t isc,
uint16_t mode)
{
KVMS390FLICState *flic = KVM_S390_FLIC(fs);
struct kvm_s390_ais_req req = {
.isc = isc,
.mode = mode,
};
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_AISM,
.addr = (uint64_t)&req,
};
if (!fs->ais_supported) {
return -ENOSYS;
}
return ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr) ? -errno : 0;
}
static int kvm_s390_inject_airq(S390FLICState *fs, uint8_t type,
uint8_t isc, uint8_t flags)
{
KVMS390FLICState *flic = KVM_S390_FLIC(fs);
uint32_t id = css_get_adapter_id(type, isc);
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_AIRQ_INJECT,
.attr = id,
};
if (!fs->ais_supported) {
return -ENOSYS;
}
return ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr) ? -errno : 0;
}
/**
* __get_all_irqs - store all pending irqs in buffer
* @flic: pointer to flic device state
* @buf: pointer to pointer to a buffer
* @len: length of buffer
*
* Returns: return value of flic_get_all_irqs
* Note: Retry and increase buffer size until flic_get_all_irqs
* either returns a value >= 0 or a negative error code.
* -ENOMEM is an exception, which means the buffer is too small
* and we should try again. Other negative error codes can be
* -EFAULT and -EINVAL which we ignore at this point
*/
static int __get_all_irqs(KVMS390FLICState *flic,
void **buf, int len)
{
int r;
do {
/* returns -ENOMEM if buffer is too small and number
* of queued interrupts on success */
r = flic_get_all_irqs(flic, *buf, len);
if (r >= 0) {
break;
}
len *= 2;
*buf = g_try_realloc(*buf, len);
if (!buf) {
return -ENOMEM;
}
} while (r == -ENOMEM && len <= KVM_S390_FLIC_MAX_BUFFER);
return r;
}
static int kvm_s390_register_io_adapter(S390FLICState *fs, uint32_t id,
uint8_t isc, bool swap,
bool is_maskable, uint8_t flags)
{
struct kvm_s390_io_adapter adapter = {
.id = id,
.isc = isc,
.maskable = is_maskable,
.swap = swap,
.flags = flags,
};
KVMS390FLICState *flic = KVM_S390_FLIC(fs);
int r;
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_ADAPTER_REGISTER,
.addr = (uint64_t)&adapter,
};
if (!kvm_gsi_routing_enabled()) {
/* nothing to do */
return 0;
}
r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
return r ? -errno : 0;
}
static int kvm_s390_io_adapter_map(S390FLICState *fs, uint32_t id,
uint64_t map_addr, bool do_map)
{
struct kvm_s390_io_adapter_req req = {
.id = id,
.type = do_map ? KVM_S390_IO_ADAPTER_MAP : KVM_S390_IO_ADAPTER_UNMAP,
.addr = map_addr,
};
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_ADAPTER_MODIFY,
.addr = (uint64_t)&req,
};
KVMS390FLICState *flic = KVM_S390_FLIC(fs);
int r;
if (!kvm_gsi_routing_enabled()) {
/* nothing to do */
return 0;
}
r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
return r ? -errno : 0;
}
static int kvm_s390_add_adapter_routes(S390FLICState *fs,
AdapterRoutes *routes)
{
int ret, i;
uint64_t ind_offset = routes->adapter.ind_offset;
for (i = 0; i < routes->num_routes; i++) {
ret = kvm_irqchip_add_adapter_route(kvm_state, &routes->adapter);
if (ret < 0) {
goto out_undo;
}
routes->gsi[i] = ret;
routes->adapter.ind_offset++;
}
kvm_irqchip_commit_routes(kvm_state);
/* Restore passed-in structure to original state. */
routes->adapter.ind_offset = ind_offset;
return 0;
out_undo:
while (--i >= 0) {
kvm_irqchip_release_virq(kvm_state, routes->gsi[i]);
routes->gsi[i] = -1;
}
routes->adapter.ind_offset = ind_offset;
return ret;
}
static void kvm_s390_release_adapter_routes(S390FLICState *fs,
AdapterRoutes *routes)
{
int i;
for (i = 0; i < routes->num_routes; i++) {
if (routes->gsi[i] >= 0) {
kvm_irqchip_release_virq(kvm_state, routes->gsi[i]);
routes->gsi[i] = -1;
}
}
}
/**
* kvm_flic_save - Save pending floating interrupts
* @f: QEMUFile containing migration state
* @opaque: pointer to flic device state
* @size: ignored
*
* Note: Pass buf and len to kernel. Start with one page and
* increase until buffer is sufficient or maxium size is
* reached
*/
static int kvm_flic_save(QEMUFile *f, void *opaque, size_t size,
VMStateField *field, QJSON *vmdesc)
{
KVMS390FLICState *flic = opaque;
int len = FLIC_SAVE_INITIAL_SIZE;
void *buf;
int count;
int r = 0;
flic_disable_wait_pfault((struct KVMS390FLICState *) opaque);
buf = g_try_malloc0(len);
if (!buf) {
/* Storing FLIC_FAILED into the count field here will cause the
* target system to fail when attempting to load irqs from the
* migration state */
error_report("flic: couldn't allocate memory");
qemu_put_be64(f, FLIC_FAILED);
return -ENOMEM;
}
count = __get_all_irqs(flic, &buf, len);
if (count < 0) {
error_report("flic: couldn't retrieve irqs from kernel, rc %d",
count);
/* Storing FLIC_FAILED into the count field here will cause the
* target system to fail when attempting to load irqs from the
* migration state */
qemu_put_be64(f, FLIC_FAILED);
r = count;
} else {
qemu_put_be64(f, count);
qemu_put_buffer(f, (uint8_t *) buf,
count * sizeof(struct kvm_s390_irq));
}
g_free(buf);
return r;
}
/**
* kvm_flic_load - Load pending floating interrupts
* @f: QEMUFile containing migration state
* @opaque: pointer to flic device state
* @size: ignored
*
* Returns: value of flic_enqueue_irqs, -EINVAL on error
* Note: Do nothing when no interrupts where stored
* in QEMUFile
*/
static int kvm_flic_load(QEMUFile *f, void *opaque, size_t size,
VMStateField *field)
{
uint64_t len = 0;
uint64_t count = 0;
void *buf = NULL;
int r = 0;
flic_enable_pfault((struct KVMS390FLICState *) opaque);
count = qemu_get_be64(f);
len = count * sizeof(struct kvm_s390_irq);
if (count == FLIC_FAILED) {
r = -EINVAL;
goto out;
}
if (count == 0) {
r = 0;
goto out;
}
buf = g_try_malloc0(len);
if (!buf) {
r = -ENOMEM;
goto out;
}
if (qemu_get_buffer(f, (uint8_t *) buf, len) != len) {
r = -EINVAL;
goto out_free;
}
r = flic_enqueue_irqs(buf, len, (struct KVMS390FLICState *) opaque);
out_free:
g_free(buf);
out:
return r;
}
typedef struct KVMS390FLICStateMigTmp {
KVMS390FLICState *parent;
uint8_t simm;
uint8_t nimm;
} KVMS390FLICStateMigTmp;
static void kvm_flic_ais_pre_save(void *opaque)
{
KVMS390FLICStateMigTmp *tmp = opaque;
KVMS390FLICState *flic = tmp->parent;
struct kvm_s390_ais_all ais;
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_AISM_ALL,
.addr = (uint64_t)&ais,
.attr = sizeof(ais),
};
if (ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr)) {
error_report("Failed to retrieve kvm flic ais states");
return;
}
tmp->simm = ais.simm;
tmp->nimm = ais.nimm;
}
static int kvm_flic_ais_post_load(void *opaque, int version_id)
{
KVMS390FLICStateMigTmp *tmp = opaque;
KVMS390FLICState *flic = tmp->parent;
struct kvm_s390_ais_all ais = {
.simm = tmp->simm,
.nimm = tmp->nimm,
};
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_AISM_ALL,
.addr = (uint64_t)&ais,
};
/* This can happen when the user mis-configures its guests in an
* incompatible fashion or without a CPU model. For example using
* qemu with -cpu host (which is not migration safe) and do a
* migration from a host that has AIS to a host that has no AIS.
* In that case the target system will reject the migration here.
*/
if (!ais_needed(flic)) {
return -ENOSYS;
}
return ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr) ? -errno : 0;
}
static const VMStateDescription kvm_s390_flic_ais_tmp = {
.name = "s390-flic-ais-tmp",
.pre_save = kvm_flic_ais_pre_save,
.post_load = kvm_flic_ais_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINT8(simm, KVMS390FLICStateMigTmp),
VMSTATE_UINT8(nimm, KVMS390FLICStateMigTmp),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription kvm_s390_flic_vmstate_ais = {
.name = "s390-flic/ais",
.version_id = 1,
.minimum_version_id = 1,
.needed = ais_needed,
.fields = (VMStateField[]) {
VMSTATE_WITH_TMP(KVMS390FLICState, KVMS390FLICStateMigTmp,
kvm_s390_flic_ais_tmp),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription kvm_s390_flic_vmstate = {
/* should have been like kvm-s390-flic,
* can't change without breaking compat */
.name = "s390-flic",
.version_id = FLIC_SAVEVM_VERSION,
.minimum_version_id = FLIC_SAVEVM_VERSION,
.fields = (VMStateField[]) {
{
.name = "irqs",
.info = &(const VMStateInfo) {
.name = "irqs",
.get = kvm_flic_load,
.put = kvm_flic_save,
},
.flags = VMS_SINGLE,
},
VMSTATE_END_OF_LIST()
},
.subsections = (const VMStateDescription * []) {
&kvm_s390_flic_vmstate_ais,
NULL
}
};
typedef struct KVMS390FLICStateClass {
S390FLICStateClass parent_class;
DeviceRealize parent_realize;
} KVMS390FLICStateClass;
#define KVM_S390_FLIC_GET_CLASS(obj) \
OBJECT_GET_CLASS(KVMS390FLICStateClass, (obj), TYPE_KVM_S390_FLIC)
#define KVM_S390_FLIC_CLASS(klass) \
OBJECT_CLASS_CHECK(KVMS390FLICStateClass, (klass), TYPE_KVM_S390_FLIC)
static void kvm_s390_flic_realize(DeviceState *dev, Error **errp)
{
KVMS390FLICState *flic_state = KVM_S390_FLIC(dev);
struct kvm_create_device cd = {0};
struct kvm_device_attr test_attr = {0};
int ret;
Error *errp_local = NULL;
KVM_S390_FLIC_GET_CLASS(dev)->parent_realize(dev, &errp_local);
if (errp_local) {
goto fail;
}
flic_state->fd = -1;
if (!kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) {
error_setg_errno(&errp_local, errno, "KVM is missing capability"
" KVM_CAP_DEVICE_CTRL");
trace_flic_no_device_api(errno);
goto fail;
}
cd.type = KVM_DEV_TYPE_FLIC;
ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd);
if (ret < 0) {
error_setg_errno(&errp_local, errno, "Creating the KVM device failed");
trace_flic_create_device(errno);
goto fail;
}
flic_state->fd = cd.fd;
/* Check clear_io_irq support */
test_attr.group = KVM_DEV_FLIC_CLEAR_IO_IRQ;
flic_state->clear_io_supported = !ioctl(flic_state->fd,
KVM_HAS_DEVICE_ATTR, test_attr);
return;
fail:
error_propagate(errp, errp_local);
}
static void kvm_s390_flic_reset(DeviceState *dev)
{
KVMS390FLICState *flic = KVM_S390_FLIC(dev);
S390FLICState *fs = S390_FLIC_COMMON(dev);
struct kvm_device_attr attr = {
.group = KVM_DEV_FLIC_CLEAR_IRQS,
};
int rc = 0;
uint8_t isc;
if (flic->fd == -1) {
return;
}
flic_disable_wait_pfault(flic);
if (fs->ais_supported) {
for (isc = 0; isc <= MAX_ISC; isc++) {
rc = kvm_s390_modify_ais_mode(fs, isc, SIC_IRQ_MODE_ALL);
if (rc) {
error_report("Failed to reset ais mode for isc %d: %s",
isc, strerror(-rc));
}
}
}
rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
if (rc) {
trace_flic_reset_failed(errno);
}
flic_enable_pfault(flic);
}
static void kvm_s390_flic_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
S390FLICStateClass *fsc = S390_FLIC_COMMON_CLASS(oc);
KVM_S390_FLIC_CLASS(oc)->parent_realize = dc->realize;
dc->realize = kvm_s390_flic_realize;
dc->vmsd = &kvm_s390_flic_vmstate;
dc->reset = kvm_s390_flic_reset;
fsc->register_io_adapter = kvm_s390_register_io_adapter;
fsc->io_adapter_map = kvm_s390_io_adapter_map;
fsc->add_adapter_routes = kvm_s390_add_adapter_routes;
fsc->release_adapter_routes = kvm_s390_release_adapter_routes;
fsc->clear_io_irq = kvm_s390_clear_io_flic;
fsc->modify_ais_mode = kvm_s390_modify_ais_mode;
fsc->inject_airq = kvm_s390_inject_airq;
}
static const TypeInfo kvm_s390_flic_info = {
.name = TYPE_KVM_S390_FLIC,
.parent = TYPE_S390_FLIC_COMMON,
.instance_size = sizeof(KVMS390FLICState),
.class_size = sizeof(KVMS390FLICStateClass),
.class_init = kvm_s390_flic_class_init,
};
static void kvm_s390_flic_register_types(void)
{
type_register_static(&kvm_s390_flic_info);
}
type_init(kvm_s390_flic_register_types)