Re: [PATCH v4 09/21] KVM: arm64: Support SDEI_EVENT_GET_INFO hypercall

Eric Auger
2021-11-09T17:20:07Z

Hi Gavin,

On 8/15/21 2:13 AM, Gavin Shan wrote:
> This supports SDEI_EVENT_GET_INFO hypercall. It's used by the guest
> to retrieve various information about the supported (exported) events,
> including type, signaled, route mode and affinity for the shared
> events.
>
> Signed-off-by: Gavin Shan <gshan@redhat.com>
> ---
> arch/arm64/kvm/sdei.c | 76 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 76 insertions(+)
>
> diff --git a/arch/arm64/kvm/sdei.c b/arch/arm64/kvm/sdei.c
> index b95b8c4455e1..5dfa74b093f1 100644
> --- a/arch/arm64/kvm/sdei.c
> +++ b/arch/arm64/kvm/sdei.c
> @@ -415,6 +415,80 @@ static unsigned long kvm_sdei_hypercall_status(struct kvm_vcpu *vcpu)
> return ret;
> }
>
> +static unsigned long kvm_sdei_hypercall_info(struct kvm_vcpu *vcpu)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + struct kvm_sdei_kvm *ksdei = kvm->arch.sdei;
> + struct kvm_sdei_vcpu *vsdei = vcpu->arch.sdei;
> + struct kvm_sdei_event *kse = NULL;
> + struct kvm_sdei_kvm_event *kske = NULL;
> + unsigned long event_num = smccc_get_arg1(vcpu);
> + unsigned long event_info = smccc_get_arg2(vcpu);
> + unsigned long ret = SDEI_SUCCESS;
> +
> + /* Sanity check */
> + if (!(ksdei && vsdei)) {
> + ret = SDEI_NOT_SUPPORTED;
> + goto out;
> + }
> +
> + if (!kvm_sdei_is_valid_event_num(event_num)) {
> + ret = SDEI_INVALID_PARAMETERS;
> + goto out;
> + }
> +
> + /*
> + * Check if the KVM event exists. The event might have been
> + * registered, we need fetch the information from the registered
s/fetch/to fetch
> + * event in that case.
> + */
> + spin_lock(&ksdei->lock);
> + kske = kvm_sdei_find_kvm_event(kvm, event_num);
> + kse = kske ? kske->kse : NULL;
> + if (!kse) {
> + kse = kvm_sdei_find_event(kvm, event_num);
> + if (!kse) {
> + ret = SDEI_INVALID_PARAMETERS;
this should have already be covered by !kvm_sdei_is_valid_event_num I
think (although this latter only checks the since static event num with
KVM owner mask)
> + goto unlock;
> + }
> + }
> +
> + /* Retrieve the requested information */
> + switch (event_info) {
> + case SDEI_EVENT_INFO_EV_TYPE:
> + ret = kse->state.type;
> + break;
> + case SDEI_EVENT_INFO_EV_SIGNALED:
> + ret = kse->state.signaled;
> + break;
> + case SDEI_EVENT_INFO_EV_PRIORITY:
> + ret = kse->state.priority;
> + break;
> + case SDEI_EVENT_INFO_EV_ROUTING_MODE:
> + case SDEI_EVENT_INFO_EV_ROUTING_AFF:
> + if (kse->state.type != SDEI_EVENT_TYPE_SHARED) {
> + ret = SDEI_INVALID_PARAMETERS;
> + break;
> + }
> +
> + if (event_info == SDEI_EVENT_INFO_EV_ROUTING_MODE) {
> + ret = kske ? kske->state.route_mode :
> + SDEI_EVENT_REGISTER_RM_ANY;
no, if event is not registered (!kske) DENIED should be returned
> + } else {
same here
> + ret = kske ? kske->state.route_affinity : 0;
> + }
> +
> + break;
> + default:
> + ret = SDEI_INVALID_PARAMETERS;
> + }
> +
> +unlock:
> + spin_unlock(&ksdei->lock);
> +out:
> + return ret;
> +}
> +
> int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
> {
> u32 func = smccc_get_function(vcpu);
> @@ -446,6 +520,8 @@ int kvm_sdei_hypercall(struct kvm_vcpu *vcpu)
> ret = kvm_sdei_hypercall_status(vcpu);
> break;
> case SDEI_1_0_FN_SDEI_EVENT_GET_INFO:
> + ret = kvm_sdei_hypercall_info(vcpu);
> + break;
> case SDEI_1_0_FN_SDEI_EVENT_ROUTING_SET:
> case SDEI_1_0_FN_SDEI_PE_MASK:
> case SDEI_1_0_FN_SDEI_PE_UNMASK:
>
Eric