Re: [RFC 0/3] DSA and Marvell 88E6352 802.1q support

[Vivien Didelot <vivien.didelot@savoirfairelinux.com>]

On May 29, 2015, at 1:02 AM, Scott Feldman sfeldma@gmail.com wrote:
> On Thu, May 28, 2015 at 2:37 PM, Vivien Didelot <vivien.didelot@savoirfairelinux.com> wrote:
>> This RFC is based on v4.1-rc3.
>>
>> It is meant to get a glance to the commits responsible to implement the
>> necessary NDOs between DSA and the Marvell 88E6352 switch driver.
>>
>> With this support, I am able to create VLANs with (un)tagged ports, setting
>> their default VID, from a bridge.
>>
>> To create a bridge containing all switch ports, with a VLAN ID 400, swp2 and
>> swp3 untagged (pvid), and swp4 tagged, the userspace commands look like this:
>>
>>     ip link add name br0 type bridge
>>     [...]
>>     ip link set dev swp2 up master br0
>>     [...]
>>     bridge vlan add vid 400 pvid untagged dev swp2
>>     bridge vlan add vid 400 pvid untagged dev swp3
>>     bridge vlan add vid 400 dev swp4
>>     [...]
>>     ip link add link br0 name br0.400 type vlan id 400
>>     [...]
>>     bridge vlan add dev br0 vid 400 self
>>
>> The code is currently being rebased to the latest net-next/master.
>>
>> Seems like the way to go now is through switchdev attr getter/setter...
> 
> Indeed, for dsa_slave you should be able to port this to switchdev and
> set your ndo_bridge_setlink/dellink handlers to
> switchdev_port_bridge_setlink/dellink.  (And also implement the
> switchdev ops for vlans).
> 
> If you use switchdev_port_bridge_setlink/dellink, you shouldn't need
> to implement ndo_vlan_rx_add_vid/ndo_vlan_rx_kill_vid at all.

Scott,

In fact I have to define these ndo, otherwise I get the "Buggy VLAN
acceleration in driver!" warning from net/core/dev.c and the switch
ports won't register.

I'm actually defining a noop function for them in dsa_slave_netdev_ops.

Is it correct to set NETIF_F_HW_VLAN_CTAG_FILTER in slave_dev->features?

> The setlink/dellink callbacks will give the same info (and more, e.g.
> pvid, untagged flags) and you'll automatically get support for stacked
> drivers, for example if you bonded swp2/3 and then included that bond
> in your vlan bridge.  Your commands will be slightly modified: when
> adding the vid to the port, specify master and self:
> 
> bridge vlan add vid 400 dev swp4 master self

Thanks it works! Now the switch VLAN database is consistent with the
bridge commands, I'm sending a complete RFC very soon.

Scott, David,

I use this mail to expose a potential problem between iproute2 and the
kernel, found with my previous code. When issuing "ip link set dev swp0
master br0", ndo_vlan_rx_add_vid is called, but not ndo_bridge_setlink,
which results in an inconsistency between my switch VLAN database (and
port settings) and "bridge vlan", which shows "swp0   1 PVID Egress
Untagged".

Seems like there is a call to ndo_bridge_setlink to add somewhere, but I
have no clue where.

In the meantime, I call "bridge vlan add vid 1 dev swp0 pvid untagged
[master self]" at boot, to be consistent with the bridge output.

Thanks,
-v