• John Fastabend's avatar
    net: set and query VEB/VEPA bridge mode via PF_BRIDGE · 2469ffd7
    John Fastabend authored
    Hardware switches may support enabling and disabling the
    loopback switch which puts the device in a VEPA mode defined
    in the IEEE 802.1Qbg specification. In this mode frames are
    not switched in the hardware but sent directly to the switch.
    SR-IOV capable NICs will likely support this mode I am
    aware of at least two such devices. Also I am told (but don't
    have any of this hardware available) that there are devices
    that only support VEPA modes. In these cases it is important
    at a minimum to be able to query these attributes.
    
    This patch adds an additional IFLA_BRIDGE_MODE attribute that can be
    set and dumped via the PF_BRIDGE:{SET|GET}LINK operations. Also
    anticipating bridge attributes that may be common for both embedded
    bridges and software bridges this adds a flags attribute
    IFLA_BRIDGE_FLAGS currently used to determine if the command or event
    is being generated to/from an embedded bridge or software bridge.
    Finally, the event generation is pulled out of the bridge module and
    into rtnetlink proper.
    
    For example using the macvlan driver in VEPA mode on top of
    an embedded switch requires putting the embedded switch into
    a VEPA mode to get the expected results.
    
    	--------  --------
            | VEPA |  | VEPA |       <-- macvlan vepa edge relays
            --------  --------
               |        |
               |        |
            ------------------
            |      VEPA      |       <-- embedded switch in NIC
            ------------------
                    |
                    |
            -------------------
            | external switch |      <-- shiny new physical
    	-------------------          switch with VEPA support
    
    A packet sent from the macvlan VEPA at the top could be
    loopbacked on the embedded switch and never seen by the
    external switch. So in order for this to work the embedded
    switch needs to be set in the VEPA state via the above
    described commands.
    
    By making these attributes nested in IFLA_AF_SPEC we allow
    future extensions to be made as needed.
    
    CC: Lennert Buytenhek <buytenh@wantstofly.org>
    CC: Stephen Hemminger <shemminger@vyatta.com>
    Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    2469ffd7
rtnetlink.c 62 KB