__MTRR_ID_BASE
(((x) < __MTRR_ID_BASE) ? -1 : ((x) - __MTRR_ID_BASE))
return (error != 0 ? -error : id + __MTRR_ID_BASE);
if (reg < __MTRR_ID_BASE)
mrdesc = idr_find(&mtrr_idr, reg - __MTRR_ID_BASE);
idr_remove(&mtrr_idr, reg - __MTRR_ID_BASE);