KVM: S390: take a full byte as ext_param indicator
Currenty the ext_param field only distinguishes between "config change" and
"vring interrupt". We can do a lot more with it though, so let's enable a
full byte of possible values and constants to #defines while at it.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/s390/include/asm/kvm_virtio.h b/arch/s390/include/asm/kvm_virtio.h
index acdfdff..3f5d100 100644
--- a/arch/s390/include/asm/kvm_virtio.h
+++ b/arch/s390/include/asm/kvm_virtio.h
@@ -54,4 +54,10 @@
* This is pagesize for historical reasons. */
#define KVM_S390_VIRTIO_RING_ALIGN 4096
+
+/* These values are supposed to be in ext_params on an interrupt */
+#define VIRTIO_PARAM_MASK 0xff
+#define VIRTIO_PARAM_VRING_INTERRUPT 0x0
+#define VIRTIO_PARAM_CONFIG_CHANGED 0x1
+
#endif
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index 4e298bc..68cef4d 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -334,7 +334,7 @@
{
struct virtqueue *vq;
u16 subcode;
- int config_changed;
+ u32 param;
subcode = S390_lowcore.cpu_addr;
if ((subcode & 0xff00) != VIRTIO_SUBCODE_64)
@@ -343,18 +343,25 @@
/* The LSB might be overloaded, we have to mask it */
vq = (struct virtqueue *)(S390_lowcore.ext_params2 & ~1UL);
- /* We use the LSB of extparam, to decide, if this interrupt is a config
- * change or a "standard" interrupt */
- config_changed = S390_lowcore.ext_params & 1;
+ /* We use ext_params to decide what this interrupt means */
+ param = S390_lowcore.ext_params & VIRTIO_PARAM_MASK;
- if (config_changed) {
+ switch (param) {
+ case VIRTIO_PARAM_CONFIG_CHANGED:
+ {
struct virtio_driver *drv;
drv = container_of(vq->vdev->dev.driver,
struct virtio_driver, driver);
if (drv->config_changed)
drv->config_changed(vq->vdev);
- } else
+
+ break;
+ }
+ case VIRTIO_PARAM_VRING_INTERRUPT:
+ default:
vring_interrupt(0, vq);
+ break;
+ }
}
/*