via-rhine rework

The series applies against davem-next as of 9dd3c797496affd699805c8a9d8429ad318c892f ("drivers: net: xgene: fix kbuild warnings").

Patches #1..#4 avoid holes in the receive ring.

Patch #5 is a small leftover cleanup for #1..#4.

Patches #6 and #7 are fairly simple barrier stuff.

Patch #8 closes some SMP transmit races - not that anyone really complained about these but it's a bit hard to handwave that they can be safely ignored. Some testing, especially SMP testing of course, would be welcome.

. Changes since #2:
- added dma_rmb barrier in vlan related patch 6.
- s/wmb/dma_wmb/ in (*new*) patch 7 of 8.
- added explicit SMP barriers in (*new*) patch 8 of 8.

. Changes since #1:
- turned wmb() into dma_wmb() as suggested by davem and Alexander Duyck in patch 1 of 6.
- forgot to reset rx_head_desc in rhine_reset_rbufs in patch 4 of 6.
- removed rx_head_desc altogether in (*new*) patch 5 of 6
- remoed some vlan receive uglyness in (*new*) patch 6 of 6.

Francois Romieu (8):
via-rhine: commit receive buffer address before descriptor status update.
via-rhine: allocate and map receive buffer in a single transaction
via-rhine: gotoize rhine_open error path.
via-rhine: forbid holes in the receive descriptor ring.
via-rhine: kiss rx_head_desc goodbye.
via-rhine: add consistent memory barrier in vlan receive code.
via-rhine: dma_wmb transmit barrier.
via-rhine: close SMP transmit races.

 drivers/net/ethernet/via/via-rhine.c | 249 +++++++++++++++++++++++------------
 1 file changed, 162 insertions(+), 87 deletions(-)

Ueimor