PPTSIZE
dtpf_entry = malloc(PPTSIZE, M_DT, M_NOWAIT|M_ZERO);
dtpf_return = malloc(PPTSIZE, M_DT, M_NOWAIT|M_ZERO);
free(dtpf_entry, M_DT, PPTSIZE);
#define PPTMASK ((PPTSIZE / sizeof(struct dt_probe)) - 1)