KVM: s390: Wire up ioeventfd.
Enable ioeventfd support on s390 and hook up diagnose 500 virtio-ccw
notifications.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index a390687..1c01a99 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -13,6 +13,7 @@
#include <linux/kvm.h>
#include <linux/kvm_host.h>
+#include <asm/virtio-ccw.h>
#include "kvm-s390.h"
#include "trace.h"
#include "trace-s390.h"
@@ -104,6 +105,29 @@
return -EREMOTE;
}
+static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
+{
+ int ret, idx;
+
+ /* No virtio-ccw notification? Get out quickly. */
+ if (!vcpu->kvm->arch.css_support ||
+ (vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY))
+ return -EOPNOTSUPP;
+
+ idx = srcu_read_lock(&vcpu->kvm->srcu);
+ /*
+ * The layout is as follows:
+ * - gpr 2 contains the subchannel id (passed as addr)
+ * - gpr 3 contains the virtqueue index (passed as datamatch)
+ */
+ ret = kvm_io_bus_write(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS,
+ vcpu->run->s.regs.gprs[2],
+ 8, &vcpu->run->s.regs.gprs[3]);
+ srcu_read_unlock(&vcpu->kvm->srcu, idx);
+ /* kvm_io_bus_write returns -EOPNOTSUPP if it found no match. */
+ return ret < 0 ? ret : 0;
+}
+
int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
{
int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
@@ -118,6 +142,8 @@
return __diag_time_slice_end_directed(vcpu);
case 0x308:
return __diag_ipl_functions(vcpu);
+ case 0x500:
+ return __diag_virtio_hypercall(vcpu);
default:
return -EOPNOTSUPP;
}