KVM: arm/arm64: vgic: Add group field to struct irq

In preparation for proper group 0 and group 1 support in the vgic, we
add a field in the struct irq to store the group of all interrupts.

We initialize the group to group 0 when emulating GICv2 and to group 1
when emulating GICv3, just like we treat them today.  LPIs are always
group 1.  We also continue to ignore writes from the guest, preserving
existing functionality, for now.

Finally, we also add this field to the vgic debug logic to show the
group for all interrupts.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

virt/kvm/arm/vgic/vgic-init.c

@@ -175,10 +175,13 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
 		irq->vcpu = NULL;
 		irq->target_vcpu = vcpu0;
 		kref_init(&irq->refcount);
-		if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
+		if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) {
 			irq->targets = 0;
-		else
+			irq->group = 0;
+		} else {
 			irq->mpidr = 0;
+			irq->group = 1;
+		}
 	}
 	return 0;
 }
@@ -227,6 +230,18 @@ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
 			/* PPIs */
 			irq->config = VGIC_CONFIG_LEVEL;
 		}
+
+		/*
+		 * GICv3 can only be created via the KVM_DEVICE_CREATE API and
+		 * so we always know the emulation type at this point as it's
+		 * either explicitly configured as GICv3, or explicitly
+		 * configured as GICv2, or not configured yet which also
+		 * implies GICv2.
+		 */
+		if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
+			irq->group = 1;
+		else
+			irq->group = 0;
 	}
 
 	if (!irqchip_in_kernel(vcpu->kvm))