int kvm_xen_vcpu_set_attr()

in kvm/xen.c [431:601]

• 151 lines of code
• 26 McCabe index (conditional complexity)

int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
{
	int idx, r = -ENOENT;

	mutex_lock(&vcpu->kvm->lock);
	idx = srcu_read_lock(&vcpu->kvm->srcu);

	switch (data->type) {
	case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO:
		/* No compat necessary here. */
		BUILD_BUG_ON(sizeof(struct vcpu_info) !=
			     sizeof(struct compat_vcpu_info));
		BUILD_BUG_ON(offsetof(struct vcpu_info, time) !=
			     offsetof(struct compat_vcpu_info, time));

		if (data->u.gpa == GPA_INVALID) {
			vcpu->arch.xen.vcpu_info_set = false;
			r = 0;
			break;
		}

		r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
					      &vcpu->arch.xen.vcpu_info_cache,
					      data->u.gpa,
					      sizeof(struct vcpu_info));
		if (!r) {
			vcpu->arch.xen.vcpu_info_set = true;
			kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
		}
		break;

	case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:
		if (data->u.gpa == GPA_INVALID) {
			vcpu->arch.xen.vcpu_time_info_set = false;
			r = 0;
			break;
		}

		r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
					      &vcpu->arch.xen.vcpu_time_info_cache,
					      data->u.gpa,
					      sizeof(struct pvclock_vcpu_time_info));
		if (!r) {
			vcpu->arch.xen.vcpu_time_info_set = true;
			kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
		}
		break;

	case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR:
		if (!sched_info_on()) {
			r = -EOPNOTSUPP;
			break;
		}
		if (data->u.gpa == GPA_INVALID) {
			vcpu->arch.xen.runstate_set = false;
			r = 0;
			break;
		}

		r = kvm_gfn_to_hva_cache_init(vcpu->kvm,
					      &vcpu->arch.xen.runstate_cache,
					      data->u.gpa,
					      sizeof(struct vcpu_runstate_info));
		if (!r) {
			vcpu->arch.xen.runstate_set = true;
		}
		break;

	case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT:
		if (!sched_info_on()) {
			r = -EOPNOTSUPP;
			break;
		}
		if (data->u.runstate.state > RUNSTATE_offline) {
			r = -EINVAL;
			break;
		}

		kvm_xen_update_runstate(vcpu, data->u.runstate.state);
		r = 0;
		break;

	case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA:
		if (!sched_info_on()) {
			r = -EOPNOTSUPP;
			break;
		}
		if (data->u.runstate.state > RUNSTATE_offline) {
			r = -EINVAL;
			break;
		}
		if (data->u.runstate.state_entry_time !=
		    (data->u.runstate.time_running +
		     data->u.runstate.time_runnable +
		     data->u.runstate.time_blocked +
		     data->u.runstate.time_offline)) {
			r = -EINVAL;
			break;
		}
		if (get_kvmclock_ns(vcpu->kvm) <
		    data->u.runstate.state_entry_time) {
			r = -EINVAL;
			break;
		}

		vcpu->arch.xen.current_runstate = data->u.runstate.state;
		vcpu->arch.xen.runstate_entry_time =
			data->u.runstate.state_entry_time;
		vcpu->arch.xen.runstate_times[RUNSTATE_running] =
			data->u.runstate.time_running;
		vcpu->arch.xen.runstate_times[RUNSTATE_runnable] =
			data->u.runstate.time_runnable;
		vcpu->arch.xen.runstate_times[RUNSTATE_blocked] =
			data->u.runstate.time_blocked;
		vcpu->arch.xen.runstate_times[RUNSTATE_offline] =
			data->u.runstate.time_offline;
		vcpu->arch.xen.last_steal = current->sched_info.run_delay;
		r = 0;
		break;

	case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST:
		if (!sched_info_on()) {
			r = -EOPNOTSUPP;
			break;
		}
		if (data->u.runstate.state > RUNSTATE_offline &&
		    data->u.runstate.state != (u64)-1) {
			r = -EINVAL;
			break;
		}
		/* The adjustment must add up */
		if (data->u.runstate.state_entry_time !=
		    (data->u.runstate.time_running +
		     data->u.runstate.time_runnable +
		     data->u.runstate.time_blocked +
		     data->u.runstate.time_offline)) {
			r = -EINVAL;
			break;
		}

		if (get_kvmclock_ns(vcpu->kvm) <
		    (vcpu->arch.xen.runstate_entry_time +
		     data->u.runstate.state_entry_time)) {
			r = -EINVAL;
			break;
		}

		vcpu->arch.xen.runstate_entry_time +=
			data->u.runstate.state_entry_time;
		vcpu->arch.xen.runstate_times[RUNSTATE_running] +=
			data->u.runstate.time_running;
		vcpu->arch.xen.runstate_times[RUNSTATE_runnable] +=
			data->u.runstate.time_runnable;
		vcpu->arch.xen.runstate_times[RUNSTATE_blocked] +=
			data->u.runstate.time_blocked;
		vcpu->arch.xen.runstate_times[RUNSTATE_offline] +=
			data->u.runstate.time_offline;

		if (data->u.runstate.state <= RUNSTATE_offline)
			kvm_xen_update_runstate(vcpu, data->u.runstate.state);
		r = 0;
		break;

	default:
		break;
	}

	srcu_read_unlock(&vcpu->kvm->srcu, idx);
	mutex_unlock(&vcpu->kvm->lock);
	return r;
}