[PATCH v6 06/20] arm/arm64: KVM: move kvm_register_device_ops() into vGIC probing

[Andre Przywara]

Currently we unconditionally register the GICv2 emulation device
during the host's KVM initialization. Since with GICv3 support we
may end up with only v2 or only v3 or both supported, we move the
registration into the GIC probing function, where we will later know
which combination is valid.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
Acked-by: Christoffer Dall <christoffer.dall at linaro.org>
Acked-by: Marc Zyngier <marc.zyngier at arm.com>
---
Changelog v5...v6:
 (add Acked-by)

Changelog v4...v5:
 (none)

Changelog v3...v4:
 (add Acked-by)

 include/linux/kvm_host.h |    1 +
 virt/kvm/arm/vgic-v2.c   |    2 ++
 virt/kvm/arm/vgic-v3.c   |    1 +
 virt/kvm/arm/vgic.c      |    5 ++---
 4 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 26f1060..703eeed 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1042,6 +1042,7 @@ void kvm_unregister_device_ops(u32 type);
 
 extern struct kvm_device_ops kvm_mpic_ops;
 extern struct kvm_device_ops kvm_xics_ops;
+extern struct kvm_device_ops kvm_arm_vgic_v2_ops;
 
 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
 
diff --git a/virt/kvm/arm/vgic-v2.c b/virt/kvm/arm/vgic-v2.c
index 2935405..e1cd3cb 100644
--- a/virt/kvm/arm/vgic-v2.c
+++ b/virt/kvm/arm/vgic-v2.c
@@ -229,6 +229,8 @@ int vgic_v2_probe(struct device_node *vgic_node,
 		goto out_unmap;
 	}
 
+	kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
+
 	vgic->vcpu_base = vcpu_res.start;
 
 	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
index 1c2c8ee..d14c75f 100644
--- a/virt/kvm/arm/vgic-v3.c
+++ b/virt/kvm/arm/vgic-v3.c
@@ -230,6 +230,7 @@ int vgic_v3_probe(struct device_node *vgic_node,
 		ret = -ENXIO;
 		goto out;
 	}
+	kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
 
 	vgic->vcpu_base = vcpu_res.start;
 	vgic->vctrl_base = NULL;
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 205df80..038d287 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -2559,7 +2559,7 @@ static int vgic_create(struct kvm_device *dev, u32 type)
 	return kvm_vgic_create(dev->kvm, type);
 }
 
-static struct kvm_device_ops kvm_arm_vgic_v2_ops = {
+struct kvm_device_ops kvm_arm_vgic_v2_ops = {
 	.name = "kvm-arm-vgic",
 	.create = vgic_create,
 	.destroy = vgic_destroy,
@@ -2638,8 +2638,7 @@ int kvm_vgic_hyp_init(void)
 
 	on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
 
-	return kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
-				       KVM_DEV_TYPE_ARM_VGIC_V2);
+	return 0;
 
 out_free_irq:
 	free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus());
-- 
1.7.9.5