virtio-scsi-ccw: use ioeventfd even when KVM is disabled

This patch is based on a similar patch from Stefan Hajnoczi -
commit c324fd0a39 ("virtio-pci: use ioeventfd even when KVM is disabled")

Do not check kvm_eventfds_enabled() when KVM is disabled since it
always returns 0.  Since commit 8c56c1a592
("memory: emulate ioeventfd") it has been possible to use ioeventfds in
qtest or TCG mode.

This patch makes -device virtio-scsi-ccw,iothread=iothread0 work even
when KVM is disabled.
Currently we don't have an equivalent to "memory: emulate ioeventfd"
for ccw yet, but that this doesn't hurt and qemu-iotests 068 can pass with
skipping iothread arguments.

I have tested that virtio-scsi-ccw works under tcg both with and without
iothread.

This patch fixes qemu-iotests 068, which was accidentally merged early
despite the dependency on ioeventfd.

Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20170704132350.11874-2-haoqf@linux.vnet.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
QingFeng Hao 2017-07-04 15:23:50 +02:00 committed by Christian Borntraeger
parent 38cba1f4d8
commit cda3c19ff5
2 changed files with 6 additions and 2 deletions

View File

@ -789,7 +789,7 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp)
sch->cssid, sch->ssid, sch->schid, sch->devno,
ccw_dev->devno.valid ? "user-configured" : "auto-configured");
if (!kvm_eventfds_enabled()) {
if (kvm_enabled() && !kvm_eventfds_enabled()) {
dev->flags &= ~VIRTIO_CCW_FLAG_USE_IOEVENTFD;
}

View File

@ -1264,7 +1264,11 @@ static inline int s390_assign_subch_ioeventfd(EventNotifier *notifier,
uint32_t sch_id, int vq,
bool assign)
{
return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
if (kvm_enabled()) {
return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
} else {
return 0;
}
}
static inline void s390_crypto_reset(void)