net: dsa: reduce number of protocol hooks
authorFlorian Fainelli <f.fainelli@gmail.com>
Thu, 28 Aug 2014 00:04:46 +0000 (17:04 -0700)
committerDavid S. Miller <davem@davemloft.net>
Thu, 28 Aug 2014 05:59:39 +0000 (22:59 -0700)
commit3e8a72d1dae374cf6fc1dba97cec663585845ff9
tree83a2ebc590d0dc90d27515dc15bf6323cb2a6c1b
parent8663dc2002b02abfe5dfb0fb7e544b81982ad95b
net: dsa: reduce number of protocol hooks

DSA is currently registering one packet_type function per EtherType it
needs to intercept in the receive path of a DSA-enabled Ethernet device.
Right now we have three of them: trailer, DSA and eDSA, and there might
be more in the future, this will not scale to the addition of new
protocols.

This patch proceeds with adding a new layer of abstraction and two new
functions:

dsa_switch_rcv() which will dispatch into the tag-protocol specific
receive function implemented by net/dsa/tag_*.c

dsa_slave_xmit() which will dispatch into the tag-protocol specific
transmit function implemented by net/dsa/tag_*.c

When we do create the per-port slave network devices, we iterate over
the switch protocol to assign the DSA-specific receive and transmit
operations.

A new fake ethertype value is used: ETH_P_XDSA to illustrate the fact
that this is no longer going to look like ETH_P_DSA or ETH_P_TRAILER
like it used to be.

This allows us to greatly simplify the check in eth_type_trans() and
always override the skb->protocol with ETH_P_XDSA for Ethernet switches
tagged protocol, while also reducing the number repetitive slave
netdevice_ops assignments.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/netdevice.h
include/net/dsa.h
include/uapi/linux/if_ether.h
net/dsa/dsa.c
net/dsa/dsa_priv.h
net/dsa/slave.c
net/dsa/tag_dsa.c
net/dsa/tag_edsa.c
net/dsa/tag_trailer.c
net/ethernet/eth.c