Re: [net-next PATCH 02/15] net: Merge VXLAN and GENEVE push notifiers into a single notifier

On Mon, Jun 13, 2016 at 2:08 PM, Hannes Frederic Sowa [off-list ref] wrote:

On 13.06.2016 21:47, Alexander Duyck wrote:

quoted

On Mon, Jun 13, 2016 at 10:57 AM, Hannes Frederic Sowa
[off-list ref] wrote:

quoted

Hi Alex,

very cool series!

On 13.06.2016 19:48, Alexander Duyck wrote:

quoted

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index d101e4d904ba..e959b6348f91 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h

@@ -1269,6 +1269,14 @@ struct net_device_ops {
      void                    (*ndo_del_geneve_port)(struct  net_device *dev,
                                                     sa_family_t sa_family,
                                                     __be16 port);
+     void                    (*ndo_add_udp_enc_port)(struct  net_device *dev,
+                                                    sa_family_t sa_family,
+                                                    __be16 port,
+                                                    unsigned int type);
+     void                    (*ndo_del_udp_enc_port)(struct  net_device *dev,
+                                                    sa_family_t sa_family,
+                                                    __be16 port,
+                                                    unsigned int type);
      void*                   (*ndo_dfwd_add_station)(struct net_device *pdev,
                                                      struct net_device *dev);
      void                    (*ndo_dfwd_del_station)(struct net_device *pdev,

What do you think about adding a struct as argument to
ndo_*_udp_enc_port? As a result we can much easier add new fields in
case future NICs allow us to e.g. specify a bound ip address?

Actually that is probably a good idea.  Suggestions on the name are
welcome.  Otherwise I will try to come up with something in a bit as I
am currently going through and flushing out all the driver specific
VXLAN and GENEVE build flags.

Hmmm... struct net_device_hw_offload, to be most generic? Maybe we can
even drop the udp_enc in the name and go completely generic:

int (*ndo_apply_offload)(..., struct hw_offload).

The only probably with generically using the offload keyword is it is
not very clear about what is going on.

For now I am just going with udp_enc_endpoint_info since that is
basically what we are passing.  Then I just use the pointer variable
ei for passing it back and forth between the functions.

(enc reminded me too much at encryption)

I don't know.  In a way that isn't too far off since we are looking at
packet data buried inside of a UDP packet.  I thought it worked based
on the fact that we have hw_enc_features which is what is used to
indicate the hw features when a packet is encapsulated.  I could add a
few more letters and move things over to "encap" if you prefer.  It
just means adding 2 more letters.

Another idea, should we add error indications also for the future? We
can signal if a specific card was not able to enable offloading.
Different situations can be signaled: port list depleted, protocol
unsupported etc.

Might make sense for later postprocessing and signaling to user space.

The problem is we are using a notifier type setup.  As such we cannot
really exit out if an error occurs on one of the ports.

- Alex