[RFC PATCH v4 5/5] kvm: arm64: Add capability check extension for ptp_kvm

[Jianyong Wu <jianyong.wu@arm.com>]

Let userspace check if there is kvm ptp service in host.
before VMs migrate to a another host, VMM may check if this
cap is available to determine the migration behaviour.

Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Suggested-by: Marc Zyngier <maz@kernel.org>
---
 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 2fe12b40d503..a0bff6002bd9 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -993,6 +993,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_ARM_SVE 170
 #define KVM_CAP_ARM_PTRAUTH_ADDRESS 171
 #define KVM_CAP_ARM_PTRAUTH_GENERIC 172
+#define KVM_CAP_ARM_KVM_PTP 173
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index bd5c55916d0d..80999985160b 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -201,6 +201,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_MP_STATE:
 	case KVM_CAP_IMMEDIATE_EXIT:
 	case KVM_CAP_VCPU_EVENTS:
+	case KVM_CAP_ARM_KVM_PTP:
 		r = 1;
 		break;
 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
-- 
2.17.1