iowait_ioww_to_iow
struct iowait *wait = iowait_ioww_to_iow(ioww);
if (wait && iowait_ioww_to_iow(wait)->sleep) {
tx->wait = iowait_ioww_to_iow(wait);
iowait_sdma_inc(iowait_ioww_to_iow(wait));
iowait_sdma_inc(iowait_ioww_to_iow(wait));
tx->wait = iowait_ioww_to_iow(wait);
iowait_sdma_add(iowait_ioww_to_iow(wait), total_count);
iowait_ioww_to_iow(wait));
tx->wait = iowait_ioww_to_iow(wait);