MAX_FETCH_BD
#if (MAX_SKB_FRAGS >= MAX_FETCH_BD - BDS_PER_TX_PKT)
if (skb_shinfo(skb)->nr_frags >= (MAX_FETCH_BD - num_tso_win_sub)) {
int wnd_size = MAX_FETCH_BD - num_tso_win_sub;
#if (MAX_SKB_FRAGS >= MAX_FETCH_BD - BDS_PER_TX_PKT)