sunvnet: add jumbo frames support

This patch set updates the sunvnet driver to version 1.6 of the VIO protocol to support per-port exchange of MTU information and allow non-standard MTU sizes, including jumbo frames.

Using large MTUs shows a > 4X throughput improvement Linux-Solaris and > 8X throughput improvement Linux-Linux.

Changes from v3:
- added version functions per Dave Miller <[email protected]>
- moved rmtu to vnet_port per Dave Miller <[email protected]>
- explicitly set options bits and capability flags to 0 per Raghuram Kothakota <[email protected]>
Changes from v2:
- make checkpatch clean
Changes from v1:
- fix brace formatting per Dave Miller <[email protected]>

David L Stevens (3):
sunvnet: upgrade to VIO protocol version 1.6
sunvnet: allow admin to set sunvnet MTU
sunvnet: generate ICMP PTMUD messages for smaller port MTUs

 arch/sparc/include/asm/vio.h       |   44 +++++++++++-
 arch/sparc/kernel/viohs.c          |   14 +++-
 drivers/net/ethernet/sun/sunvnet.c |  144 +++++++++++++++++++++++++++++++-----
 drivers/net/ethernet/sun/sunvnet.h |    3 +
 4 files changed, 182 insertions(+), 23 deletions(-)