Re: [PATCH v2 05/19] net/xsc: add ioctl command interface

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 13 Sep 2024 10:55:08 +0800
"WanRenyong" <wanry@yunsilicon.com> wrote:

> >  
> >> Ioctl API is used for interaction between PMD and kernel driver. As you
> >> said, ioctl is
> >>
> >> the worst API, should I consider using read and write instead?  
> > It seemed the ioctl couldn't handle VF located in VM, and interact 
> > with PF driver which run in host kernel.  
> >> If not, could you please give me some advice?  
> > If your NIC support firmware, could consider use firmware as mid-man between DPDK and kernel.
> >  
> >>  
> Hello, fengchenwen,
> 
> Thanks for your reply.
> Sorry for not describing it clearly. We know how to implement the 
> bifurcation functionality. The main issue is that ioctl is used 
> forcommunication with the kernel driver by PMD, but ioctl is not 
> considered a good API, we need to find a better approach. Implemented 
> via firmware might be a good idea, but it's complex, we can think about 
> it in the further.Recently shoud I consider using read and write 
> instead?  Is there any advise?


There are already several pre-existing ways to do bifurcation in drivers.
1. RDMA which is used by mlx5 and mana drivers.
2. using SR-IOV and queue steering. (Intel did this but not sure if it still exists)
3. BPF

It seems unlikely a new approach using ioctl() that only works on your device
would be accepted by the netdev developers.