ofproto-dpif.at: Fix a race in "ofproto-dpif - controller"

Simon Horman submitted the identical patch independently.

Acked-by: Ben Pfaff <blp@nicira.com>
Tested-by: Lori Jakab <lojakab@cisco.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Avoid races in table miss tests

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
learn.at: Fix a race in "self-modifying flow with idle_timeout" test

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Fix some races in MPLS actions tests

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Fix a race in fin_timeout test

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Fix a race in "flow stats" test

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Fix races in "NetFlow flow expiration" tests

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
learn.at: Fix a race in "self-modifying flow with hard_timeout"

Also, add a comment to explain the expected sequences.

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
learn.at: Fix a race in "learn refreshes hard_age" test

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
ofproto-dpif.at: Fix a race in "idle_age and hard_age increase over time"

Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
userspace: add support for pop_eth and push_eth actions

These actions will allow L2->L3 and L3->L2 switching, and are supposed
to be added to flows installed in the datapath transparently by
ovs-vswitchd.

Signed-off-by: Lorand Jakab <lojakab@cisco.com>
userspace: add layer 3 flow and switching support

This commit relaxes the assumption that all packets have an Ethernet
header, and adds support for layer 3 flows.  For each packet received on
the Linux kernel datapath the l2 and l3 members of struct ofpbuf are
intialized appropriately, and some functions now expect this (notably
flow_extract()), in order to differentiate between layer 2 and layer 3
packets.  struct flow has now a new 'base_layer' member, because we
cannot assume that a flow has no Ethernet header when eth_src and
eth_dst are 0.  For layer 3 packets, the protocol type is still stored
in the eth_type member.

Switching L2->L3 and L3->L2 are both implemented by adding the pop_eth
and push_eth actions respectively when a transition is detected.  The
push_eth action puts 0s on both source and destination MACs.  These
addresses can be modified with mod_dl_dst and mod_dl_src actions.

Added new prerequisite MFP_ETHERNET for fields MFF_ETH_SRC, MFF_ETH_DST,
MFF_VLAN_TCI, MFF_DL_VLAN, MFF_VLAN_VID and MFF_DL_VLAN_PCP.

Signed-off-by: Lorand Jakab <lojakab@cisco.com>
datapath: add layer 3 flow/port support

Implementation of the pop_eth and push_eth actions in the kernel, and
layer 3 flow support.

Signed-off-by: Lorand Jakab <lojakab@cisco.com>