SA_GET_DB
db = SA_GET_DB(hdl, buftype);
dmu_buf_impl_t *db = SA_GET_DB(hdl, buftype);
bonustype = SA_BONUSTYPE_FROM_DB(SA_GET_DB(hdl, SA_BONUS));
((sa_hdr_phys_t *)((dmu_buf_impl_t *)(SA_GET_DB(hdl, \