- /*
- * We would really like to pull as many bytes as we could possibly
- * want to parse into the linear data area. Currently, for IPv4,
- * that is:
- *
- * 14 Ethernet header
- * 4 VLAN header
- * 60 max IP header with options
- * 20 max TCP/UDP/ICMP header (don't care about options)
- * --
- * 98
- *
- * But Xen only allocates 64 or 72 bytes for the linear data area in
- * netback, which means that we would reallocate and copy the skb's
- * linear data on every packet if we did that. So instead just pull 64
- * bytes, which is always sufficient without IP options, and then check
- * whether we need to pull more later when we look at the IP header.
- */
- if (!pskb_may_pull(skb, min(skb->len, 64u)))
- return -ENOMEM;
-