Instead of forward() deciding packet destination make it collect input
for RSS hash function depending on packet type. After data is collected
use toeplitz hash function to calculate packet's destination.
Instead of returning special value from forward() to broadcast arm reply
call arp.learn() on all cpus at arp protocol lever. The ability of
forward() to return special value will be removed by later patches.
Some packets, like arp replies, are broadcast to all cpus for handling,
but only packet structure is copied for each cpu, the actual packet data
is the same for all of them. Currently networking stack mangles a
packet data during its travel up the stack while doing ntoh()
translations which cannot obviously work for broadcaster packets. This
patches fixes the code to not modify packet data while doing ntoh(), but
do it in a stack allocated copy of a data instead.
Classifier returns what cpu a packets should be processed on. It may
return special broadcast identifier. The patch includes classifier for
tcp, udp and arp. Arp classifier broadcasts arp reply to all cpus. Default
classifier does not forward packet.
