Oliver Hartkopp wrote: > Hello Patrick and Jamal, > > as i felt a bit misunderstood in the discussion about the usage of > skb->iif and the idea behind the virtual CAN driver i created four > PDF-slides to clarify some issues. The slides may give you the > appropriate background why the incoming (receiving) interface is > relevant at user level (which is unusual e.g. for PF_INET). Additionally > i collected some points what the VCAN driver does - and especially what > it is not for. So you will see, that approaches like VLAN (regarding > IEEE 802.1Q) is nothing that can be done with the CAN bus by design. The > PDF can be found at the BerliOS OSS server: > > http://download.berlios.de/socketcan/iif_and_vcan.pdf
I normally wouldn't have gone reading some PDF to explain a patch, but this one was really worth it .. a couple of pictures of cars with four applications using can0-can3 :) > After reading the PDF ... > > @Patrick: The (optional) loading of the vcan module and the > specification of the needed number of vcan devices (for the wanted > use-case) was a very easy thing up to now that did not require any > additional configuration nor additional userspace tools (except saying > 'ifconfig vcan0 up'). As only the use-case required number of interfaces > are allocated at module load time, i do not see a need for an extra > netlink interface to implement an IMHO obsolete vcan add/remove > mechanism. What could the implementation of the netlink API bring for > the vcan driver use-case? You keep talkign about "the use-case". This is *your* usage case any just because *you* need four interfaces doesn't mean everyone else on the world does too. Your last slide brings it to the point: "... configured at module load time for the needed use-case: - number of created vcan devices (current default=4) - perform the loopback on driver level (current default=off)" So you *do* have parameters for configuration and you're using the wrong interface. Either drop them or use the correct interface. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
