Network defrag

I finally fixed the defrag code, testing with NFS as well. Didn't take performance figures, tough, for lack of time.

I wanted to do "config + environment" for the NFS case, like tftp, but didnt' do the second step out of laziness (also, the source file has long lines while I have 80 columns).

For the record, I added the check on ip_src and ip_dst, but everything stopped working. So I reverted that instead of entering a long debugging session.

The CONFIG_NET_MAXDEFRAG argument is the actual payload, so I add NFS overhead to that figure, which is expected to a beautiful 4096 or 8192. I feel this is better than other options, as the person writing the config is not expected to know how much protocol overhead is there.

Alessandro Rubini (4):
net: defragment IP packets
tftp: get the tftp block size from config file and from the
environment
nfs: accept CONFIG_NFS_READ_SIZE from config file arm nomadik: activate defrag choose 4k transfer block size

 include/configs/nhk8815.h |    4 +
 net/net.c                 |  188 +++++++++++++++++++++++++++++++++++++++++++-
 net/nfs.h                 |   10 ++-
 net/tftp.c                |   13 +++-
 4 files changed, 206 insertions(+), 9 deletions(-)