On Fri, May 10, 2019 at 08:31:02AM -0500, Shiraz Saleem wrote: > On Wed, Mar 13, 2019 at 07:28:41AM -0600, Jason Gunthorpe wrote: > > > > > > Register a device driver to the driver core and wait for the driver > > > > core to call that driver's probe method. > > > > > > Yes, the LAN PF driver is the software component exposing and managing the > > > bus, so it is the one who will call probe/remove of the peer driver (RDMA > > > driver). Although netdev notifiers based approach is needed if the RDMA > > > driver was loaded first before the LAN PF driver (i40e or ice) is loaded. > > > > Why would notifiers be needed? Driver core handles all these ordering > > things. If you have a device_driver with no device it waits until a > > device gets plugged in to call probe. > > > > Hi Jason - Your feedback here is much appreciated and we have revisited our design based on it. > The platform driver/device model is a good fit for us with the addition of RDMA capable devices > to the virtual platform bus. Here are the highlights of design and how they address your concerns. > > (1) irdma driver registers itself as a platform driver with its own probe()/remove() routines. > It will support RDMA capable platform devices from different Intel HW generations. > (2) The intel net driver will register RDMA capable devices on the platform bus. > (3) Exposing a virtual bus type in the netdev driver is redundant and thus removed. > Additionally, it would require the bus object to be exported in order for irdma to register, > which doesnt allow irdma to be unified. > (4) In irdma bus probe(), we are able to reach each platform dev's associated net-specific > data including the netdev. > (5) There are no ordering dependencies between net-driver and irdma since it's managed by driver > core as you stated. Listening to netdev notifiers for attachment is no longer required and > thus removed. This sounds a bount right, but you will want to run these details by Greg KH. I think he will tell you to use the multi-function device stuff, not a platform device. Jason
