[Bridge] [RFC PATCH v2 net-next 0/7] Non-promisc bidge ports support

[Vlad Yasevich]

This patch series is a re-implementation of prior attempts to support
non-promiscuous bridge ports.

The basic concept is the same as before.  The bridge keeps
track of the ports that support learning and flooding packets
to unknown destinations.  We call these ports auto-discovery
ports since they automatically discover who is behind them through
learning and flooding.  

If flooding and learning are disabled via flags, then the port
requires static configuration to tell it which mac addresses
are behind it.  This is accomplished through adding of fdbs.
These fdbs should be static as dynamic fdbs can expire and systems
will become unreachable due to lack of flooding.

If the user marks all ports are needing static configuration then
we can safely make them non-promiscuous, we will know all the
information about them.

If the user leaves only 1 port as automatic, then we can mark
that port as not-promiscuous as well.  One could think of
this a edge relay similar to what's support by embedded switches
in SRIOV devices.  Since we have all the information about the
other ports, we can just program the mac addresses into the
single automatic port to receive all necessary traffic.

In other cases, we keep all ports promiscuous as before.

There are some other cases when promiscuous mode has to be turned
back on.  One is when the bridge itself if placed in promiscuous
mode (use sets promisc flag).  The other is if vlan filtering is
turned off.  Since this is the default configuration, the default
bridge operation is not changed.

Changes since v1:
 - Removed private list.  We now traverse the fdb hashtable itself
   to write necessary addresses to the ports (Stephen's concern)
 - Add learning flag to the mask for flags that decides if the port
   is 'auto' or not (suggest by MST and Jamal).
 - Simplified tracking of such ports at the cost of a loop over all
   ports (suggested by MST)

I've played with quite a large number of ports and the current approach
seems to work fairly well.

Thanks
-vlad

Vlad Yasevich (7):
  bridge: Turn flag change macro into a function.
  bridge: Keep track of ports capable of automatic discovery.
  bridge: Add functionality to sync static fdb entries to hw
  bridge: Automatically manage port promiscuous mode.
  bridge: Add addresses from static fdbs to non-promisc ports
  bridge: Correctly manage promiscuity when user requested it.
  bridge: Automatically manage promisc mode when vlan filtering is on.

 net/bridge/br_device.c   |   7 +++
 net/bridge/br_fdb.c      | 132 ++++++++++++++++++++++++++++++++++++++++++++---
 net/bridge/br_if.c       | 119 ++++++++++++++++++++++++++++++++++++++++--
 net/bridge/br_netlink.c  |   3 ++
 net/bridge/br_private.h  |  20 +++++++
 net/bridge/br_sysfs_if.c |  31 +++++++----
 net/bridge/br_vlan.c     |   1 +
 7 files changed, 293 insertions(+), 20 deletions(-)

-- 
1.9.0