mhioc_preemptandabort_t
mhioc_preemptandabort_t *ptr =
(mhioc_preemptandabort_t *)usr_bufp;
mhioc_preemptandabort_t preempt_abort;
sizeof (mhioc_preemptandabort_t),
mhioc_preemptandabort_t mhd_preempt;