KVM: device: add simple registration mechanism for kvm_device_ops
kvm_ioctl_create_device currently has knowledge of all the device types
and their associated ops. This is fairly inflexible when adding support
for new in-kernel device emulations, so move what we currently have out
into a table, which can support dynamic registration of ops by new
drivers for virtual hardware.
Cc: Alex Williamson <Alex.Williamson@redhat.com>
Cc: Alex Graf <agraf@suse.de>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c338599..686d783 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2272,6 +2272,41 @@
return filp->private_data;
}
+static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
+#ifdef CONFIG_KVM_MPIC
+ [KVM_DEV_TYPE_FSL_MPIC_20] = &kvm_mpic_ops,
+ [KVM_DEV_TYPE_FSL_MPIC_42] = &kvm_mpic_ops,
+#endif
+
+#ifdef CONFIG_KVM_XICS
+ [KVM_DEV_TYPE_XICS] = &kvm_xics_ops,
+#endif
+
+#ifdef CONFIG_KVM_VFIO
+ [KVM_DEV_TYPE_VFIO] = &kvm_vfio_ops,
+#endif
+
+#ifdef CONFIG_KVM_ARM_VGIC
+ [KVM_DEV_TYPE_ARM_VGIC_V2] = &kvm_arm_vgic_v2_ops,
+#endif
+
+#ifdef CONFIG_S390
+ [KVM_DEV_TYPE_FLIC] = &kvm_flic_ops,
+#endif
+};
+
+int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
+{
+ if (type >= ARRAY_SIZE(kvm_device_ops_table))
+ return -ENOSPC;
+
+ if (kvm_device_ops_table[type] != NULL)
+ return -EEXIST;
+
+ kvm_device_ops_table[type] = ops;
+ return 0;
+}
+
static int kvm_ioctl_create_device(struct kvm *kvm,
struct kvm_create_device *cd)
{
@@ -2280,36 +2315,12 @@
bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
int ret;
- switch (cd->type) {
-#ifdef CONFIG_KVM_MPIC
- case KVM_DEV_TYPE_FSL_MPIC_20:
- case KVM_DEV_TYPE_FSL_MPIC_42:
- ops = &kvm_mpic_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_XICS
- case KVM_DEV_TYPE_XICS:
- ops = &kvm_xics_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_VFIO
- case KVM_DEV_TYPE_VFIO:
- ops = &kvm_vfio_ops;
- break;
-#endif
-#ifdef CONFIG_KVM_ARM_VGIC
- case KVM_DEV_TYPE_ARM_VGIC_V2:
- ops = &kvm_arm_vgic_v2_ops;
- break;
-#endif
-#ifdef CONFIG_S390
- case KVM_DEV_TYPE_FLIC:
- ops = &kvm_flic_ops;
- break;
-#endif
- default:
+ if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
return -ENODEV;
- }
+
+ ops = kvm_device_ops_table[cd->type];
+ if (ops == NULL)
+ return -ENODEV;
if (test)
return 0;