typedef size_t (*skb_read_actor_t)(skb_reader_t *desc, void *to, size_t len);
+size_t xdr_skb_read_bits(skb_reader_t *desc, void *to, size_t len);
extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
skb_reader_t *, skb_read_actor_t);