SKB_GSO_CB 3223 include/linux/skbuff.h SKB_GSO_CB(inner_skb)->mac_offset; SKB_GSO_CB 3237 include/linux/skbuff.h SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom); SKB_GSO_CB 3251 include/linux/skbuff.h int plen = SKB_GSO_CB(skb)->csum_start - skb_headroom(skb) - SKB_GSO_CB 3258 include/linux/skbuff.h SKB_GSO_CB(skb)->csum_start -= plen;