Hi tom:
The generic workflow of mdev is described in
Documentation/driver-api/vfio-mediated-device.rst, I could also share
some code offline.
But now I got the comments from Alex that it may not suitable we
implement the mdev for dfl devices. I think we need to first of all
reconsider the design.
Thanks,
Yilun
On Wed, Sep 09, 2020 at 02:13:59PM -0700, Tom Rix wrote:
> This is a new interface, the documentation needs to go
>
> into greater detail. I am particularly interested in the user workflow.
>
> This seems like it would work only for kernel modules.
>
> Please describe both in the documentation.
>
> A sample of a user mode driver would be helpful.
>
> Is putting driver_override using sysfs for each device scalable ? would a list sets of {feature id,files}'s the vfio driver respond to better ?
>
> To be consistent the mdev driver file name should be dfl-vfio-mdev.c
>
> There should be an opt-in flag for drivers being overridden instead of blanket approval of all drivers.
>
> Tom
>
> On 9/8/20 12:13 AM, Xu Yilun wrote:
> > These patches depend on the patchset: "Modularization of DFL private
> > feature drivers" & "add dfl bus support to MODULE_DEVICE_TABLE()"
> >
> > https://lore.kernel.org/linux-fpga/1599488581-16386-1-git-send-email-yilun.xu@xxxxxxxxx/
> >
> > This patchset provides an VFIO Mdev driver for dfl devices. It makes
> > possible for dfl devices be direct accessed from userspace.
> >
> > Xu Yilun (3):
> > fpga: dfl: add driver_override support
> > fpga: dfl: VFIO mdev support for DFL devices
> > Documentation: fpga: dfl: Add description for VFIO Mdev support
> >
> > Documentation/ABI/testing/sysfs-bus-dfl | 20 ++
> > Documentation/fpga/dfl.rst | 20 ++
> > drivers/fpga/Kconfig | 9 +
> > drivers/fpga/Makefile | 1 +
> > drivers/fpga/dfl.c | 54 ++++-
> > drivers/fpga/vfio-mdev-dfl.c | 391 ++++++++++++++++++++++++++++++++
> > include/linux/fpga/dfl-bus.h | 2 +
> > 7 files changed, 496 insertions(+), 1 deletion(-)
> > create mode 100644 drivers/fpga/vfio-mdev-dfl.c
> >
