Re: [RFC 15/18] vfio/iommufd: Implement iommufd backend

Jason Gunthorpe
2022-04-26T13:53:53Z

On Tue, Apr 26, 2022 at 05:55:29PM +0800, Yi Liu wrote:
> > I also suggest falling back to using "/dev/char/%u:%u" if the above
> > does not exist which prevents "vfio/devices/vfio" from turning into
> > ABI.
>
> do you mean there is no matched file under /dev/vfio/devices/? Is this
> possible?

The layout of /dev/ depens on udev rules, so it is possible. I only
suggested it to avoid creating ABI here.

> > It would be a good idea to make a general open_cdev function that does
> > all this work once the sysfs is found and cdev read out of it, all the
> > other vfio places can use it too.
>
> hmmm, it's good to have a general open_cdev() function. But I guess this
> is the only place in VFIO to open the device cdev. Do you mean the vdpa
> stuffes?

Any place that starts from a sysfs name would be interested - I don't
know what vdpa does

Jason