[PATCH v7 09/22] KVM: arm64: Support EVENT_GET_INFO hypercall

[Gavin Shan <gshan@redhat.com>]

This supports EVENT_GET_INFO hypercall. It's used to retrieve
information about the event: type, signaled, priority, routing
mode and affinity.

All supported events are private and have normal priority.
Besides, all supported events can be signaled from software.
It means we just return fixed value for type/signaled/priority.

As the routing mode and affinity are only available for the
shared event, which is unsupported. So SDEI_INVALID_PARAMETERS
is returned when they're requested.

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 arch/arm64/kvm/sdei.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/arm64/kvm/sdei.c b/arch/arm64/kvm/sdei.c
index 377341f229da..cea523418c75 100644
--- a/arch/arm64/kvm/sdei.c
+++ b/arch/arm64/kvm/sdei.c
@@ -137,6 +137,38 @@ static unsigned long event_status(struct kvm_vcpu *vcpu)
 	return ret;
 }
 
+static unsigned long event_info(struct kvm_vcpu *vcpu)
+{
+	unsigned int num = smccc_get_arg(vcpu, 1);
+	unsigned int info = smccc_get_arg(vcpu, 2);
+	unsigned long ret = 0;
+
+	if (num >= KVM_NR_SDEI_EVENTS)
+		return SDEI_INVALID_PARAMETERS;
+
+	/*
+	 * All supported events are private and have normal priority.
+	 * Besides, all supported events can be signaled by software
+	 */
+	switch (info) {
+	case SDEI_EVENT_INFO_EV_TYPE:
+		ret = SDEI_EVENT_TYPE_PRIVATE;
+		break;
+	case SDEI_EVENT_INFO_EV_SIGNALED:
+		ret = 1;
+		break;
+	case SDEI_EVENT_INFO_EV_PRIORITY:
+		ret = SDEI_EVENT_PRIORITY_NORMAL;
+		break;
+	case SDEI_EVENT_INFO_EV_ROUTING_MODE:
+	case SDEI_EVENT_INFO_EV_ROUTING_AFF:
+	default:
+		ret = SDEI_INVALID_PARAMETERS;
+	}
+
+	return ret;
+}
+
 int kvm_sdei_call(struct kvm_vcpu *vcpu)
 {
 	struct kvm_sdei_vcpu *vsdei = vcpu->arch.sdei;
@@ -173,6 +205,9 @@ int kvm_sdei_call(struct kvm_vcpu *vcpu)
 	case SDEI_1_0_FN_SDEI_EVENT_STATUS:
 		ret = event_status(vcpu);
 		break;
+	case SDEI_1_0_FN_SDEI_EVENT_GET_INFO:
+		ret = event_info(vcpu);
+		break;
 	default:
 		ret = SDEI_NOT_SUPPORTED;
 	}
-- 
2.23.0