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>

1 files changed, 16 insertions, 6 deletions

diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 0695a1e3e332..60768822b140 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -943,15 +943,25 @@ struct kvm_device_attr {
         __u64   addr;           /* userspace address of attr data */
 };
 
-#define KVM_DEV_TYPE_FSL_MPIC_20        1
-#define KVM_DEV_TYPE_FSL_MPIC_42        2
-#define KVM_DEV_TYPE_XICS               3
-#define KVM_DEV_TYPE_VFIO               4
 #define  KVM_DEV_VFIO_GROUP                     1
 #define   KVM_DEV_VFIO_GROUP_ADD                        1
 #define   KVM_DEV_VFIO_GROUP_DEL                        2
-#define KVM_DEV_TYPE_ARM_VGIC_V2        5
-#define KVM_DEV_TYPE_FLIC               6
+
+enum kvm_device_type {
+        KVM_DEV_TYPE_FSL_MPIC_20        = 1,
+#define KVM_DEV_TYPE_FSL_MPIC_20        KVM_DEV_TYPE_FSL_MPIC_20
+        KVM_DEV_TYPE_FSL_MPIC_42,
+#define KVM_DEV_TYPE_FSL_MPIC_42        KVM_DEV_TYPE_FSL_MPIC_42
+        KVM_DEV_TYPE_XICS,
+#define KVM_DEV_TYPE_XICS               KVM_DEV_TYPE_XICS
+        KVM_DEV_TYPE_VFIO,
+#define KVM_DEV_TYPE_VFIO               KVM_DEV_TYPE_VFIO
+        KVM_DEV_TYPE_ARM_VGIC_V2,
+#define KVM_DEV_TYPE_ARM_VGIC_V2        KVM_DEV_TYPE_ARM_VGIC_V2
+        KVM_DEV_TYPE_FLIC,
+#define KVM_DEV_TYPE_FLIC               KVM_DEV_TYPE_FLIC
+        KVM_DEV_TYPE_MAX,
+};
 
 /*
  * ioctls for VM fds