#define PKTDATA(osh, skb) (((struct sk_buff*)(skb))->data)
#define PKTLEN(osh, skb) (((struct sk_buff*)(skb))->len)
#define PKTHEADROOM(osh, skb) (PKTDATA(osh, skb)-(((struct sk_buff*)(skb))->head))
#define PKTDATA(osh, skb) (((struct sk_buff*)(skb))->data)
#define PKTLEN(osh, skb) (((struct sk_buff*)(skb))->len)
#define PKTHEADROOM(osh, skb) (PKTDATA(osh, skb)-(((struct sk_buff*)(skb))->head))