[PATCH v5 12/22] KVM: arm64: Support SDEI_{PRIVATE, SHARED}_RESET

[Gavin Shan <gshan@redhat.com>]

This supports SDEI_{PRIVATE, SHARED}_RESET. They are used by the
guest to reset the private events on the calling vCPU or the
shared events on all vCPUs.

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 arch/arm64/kvm/sdei.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/arch/arm64/kvm/sdei.c b/arch/arm64/kvm/sdei.c
index b2a916724cfa..0dec35a0eed1 100644
--- a/arch/arm64/kvm/sdei.c
+++ b/arch/arm64/kvm/sdei.c
@@ -637,6 +637,31 @@ static unsigned long hypercall_mask(struct kvm_vcpu *vcpu, bool mask)
 	return ret;
 }
 
+static unsigned long hypercall_reset(struct kvm_vcpu *vcpu, bool private)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_sdei_kvm *ksdei = kvm->arch.sdei;
+	struct kvm_sdei_exposed_event *exposed_event;
+	struct kvm_sdei_registered_event *registered_event, *tmp;
+	unsigned long r, ret = SDEI_SUCCESS;
+
+	spin_lock(&ksdei->lock);
+
+	list_for_each_entry_safe(registered_event, tmp,
+				 &ksdei->registered_events, link) {
+		exposed_event = registered_event->exposed_event;
+		if (private ^ kvm_sdei_is_shared(exposed_event->state.type))
+			continue;
+
+		r = unregister_one_event(kvm, NULL, registered_event);
+		ret = (r == SDEI_SUCCESS) ? ret : r;
+	}
+
+	spin_unlock(&ksdei->lock);
+
+	return ret;
+}
+
 int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
@@ -700,8 +725,14 @@ int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
 	case SDEI_1_0_FN_SDEI_INTERRUPT_BIND:
 	case SDEI_1_0_FN_SDEI_INTERRUPT_RELEASE:
 	case SDEI_1_1_FN_SDEI_EVENT_SIGNAL:
+		ret = SDEI_NOT_SUPPORTED;
+		break;
 	case SDEI_1_0_FN_SDEI_PRIVATE_RESET:
+		ret = hypercall_reset(vcpu, true);
+		break;
 	case SDEI_1_0_FN_SDEI_SHARED_RESET:
+		ret = hypercall_reset(vcpu, false);
+		break;
 	case SDEI_1_1_FN_SDEI_FEATURES:
 	default:
 		ret = SDEI_NOT_SUPPORTED;
-- 
2.23.0