[RFC PATCH 9/9] arm/arm64: Add kvm capability check extension for ptp_kvm

[Jianyong Wu]

Let userspace check if there is kvm ptp service in host.
Before VMs migrate to another host, VMM may check if this
cap is available to determine the next behavior.

Signed-off-by: Jianyong Wu <jianyong.wu@xxxxxxx>
Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
---
 include/uapi/linux/kvm.h | 1 +
 virt/kvm/arm/arm.c       | 1 +
 2 files changed, 2 insertions(+)

diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index f0a16b4adbbd..ca29f6a09c30 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1009,6 +1009,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_PPC_GUEST_DEBUG_SSTEP 176
 #define KVM_CAP_ARM_NISV_TO_USER 177
 #define KVM_CAP_ARM_INJECT_EXT_DABT 178
+#define KVM_CAP_ARM_KVM_PTP 179
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 8de4daf25097..9cad433507df 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -223,6 +223,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
 	case KVM_CAP_ARM_NISV_TO_USER:
 	case KVM_CAP_ARM_INJECT_EXT_DABT:
+	case KVM_CAP_ARM_KVM_PTP:
 		r = 1;
 		break;
 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
-- 
2.17.1