static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
			 u32 msr, u64 data, bool host)
{
	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
	int ret;

	if (!synic->active && (!host || data))
		return 1;

	trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);

	ret = 0;
	switch (msr) {
	case HV_X64_MSR_SCONTROL:
		synic->control = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_SVERSION:
		if (!host) {
			ret = 1;
			break;
		}
		synic->version = data;
		break;
	case HV_X64_MSR_SIEFP:
		if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
		    !synic->dont_zero_synic_pages)
			if (kvm_clear_guest(vcpu->kvm,
					    data & PAGE_MASK, PAGE_SIZE)) {
				ret = 1;
				break;
			}
		synic->evt_page = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_SIMP:
		if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
		    !synic->dont_zero_synic_pages)
			if (kvm_clear_guest(vcpu->kvm,
					    data & PAGE_MASK, PAGE_SIZE)) {
				ret = 1;
				break;
			}
		synic->msg_page = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_EOM: {
		int i;

		if (!synic->active)
			break;

		for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
			kvm_hv_notify_acked_sint(vcpu, i);
		break;
	}
	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
		ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
		break;
	default:
		ret = 1;
		break;
	}
	return ret;
}
static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
			 u32 msr, u64 data, bool host)
{
	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
	int ret;

	if (!synic->active && (!host || data))
		return 1;

	trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);

	ret = 0;
	switch (msr) {
	case HV_X64_MSR_SCONTROL:
		synic->control = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_SVERSION:
		if (!host) {
			ret = 1;
			break;
		}
		synic->version = data;
		break;
	case HV_X64_MSR_SIEFP:
		if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
		    !synic->dont_zero_synic_pages)
			if (kvm_clear_guest(vcpu->kvm,
					    data & PAGE_MASK, PAGE_SIZE)) {
				ret = 1;
				break;
			}
		synic->evt_page = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_SIMP:
		if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
		    !synic->dont_zero_synic_pages)
			if (kvm_clear_guest(vcpu->kvm,
					    data & PAGE_MASK, PAGE_SIZE)) {
				ret = 1;
				break;
			}
		synic->msg_page = data;
		if (!host)
			synic_exit(synic, msr);
		break;
	case HV_X64_MSR_EOM: {
		int i;

		if (!synic->active)
			break;

		for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
			kvm_hv_notify_acked_sint(vcpu, i);
		break;
	}
	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
		ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
		break;
	default:
		ret = 1;
		break;
	}
	return ret;
}