Re: [virtio-dev] [PATCH] virtio_pci: support enabling VFs

From: Michael S. Tsirkin
Date: Wed May 30 2018 - 12:09:46 EST


On Wed, May 30, 2018 at 04:03:37PM +0000, Rustad, Mark D wrote:
> On May 30, 2018, at 1:55 AM, Tiwei Bie <tiwei.bie@xxxxxxxxx> wrote:
>
> > There is a new feature bit allocated in virtio spec to
> > support SR-IOV (Single Root I/O Virtualization):
> >
> > https://github.com/oasis-tcs/virtio-spec/issues/11
> >
> > This patch enables the support for this feature bit in
> > virtio driver.
> >
> > Signed-off-by: Tiwei Bie <tiwei.bie@xxxxxxxxx>
> > ---
> > This patch depends on below proposal:
> > https://lists.oasis-open.org/archives/virtio-dev/201805/msg00154.html
> >
> > This patch depends on below patch:
> > https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/commit/?h=pci/virtualization&id=8effc395c2097e258fcedfc02ed4a66d45fb4238
> >
> > drivers/virtio/virtio_pci_common.c | 20 ++++++++++++++++++++
> > drivers/virtio/virtio_pci_modern.c | 14 ++++++++++++++
> > include/uapi/linux/virtio_config.h | 7 ++++++-
> > 3 files changed, 40 insertions(+), 1 deletion(-)
> >
>
> <snip>
>
> > diff --git a/include/uapi/linux/virtio_config.h
> > b/include/uapi/linux/virtio_config.h
> > index 308e2096291f..b7c1f4e7d59e 100644
> > --- a/include/uapi/linux/virtio_config.h
> > +++ b/include/uapi/linux/virtio_config.h
> > @@ -49,7 +49,7 @@
>
> There is a value in the comment directly before this that should
> be updated as well to be consistent with the new value for
> VIRTIO_TRANSPORT_F_END below.

It hasn't been updated to 34 yet.
I suggest a separate patch to replace the numbers with
VIRTIO_TRANSPORT_F_START and VIRTIO_TRANSPORT_F_END
in the comment.
Maybe replace "e.g. virtio_ring" with "e.g. virtio_ring,
virtio_pci etc." as well.

> > * transport being used (eg. virtio_ring), the rest are per-device feature
> > * bits. */
> > #define VIRTIO_TRANSPORT_F_START 28
> > -#define VIRTIO_TRANSPORT_F_END 34
> > +#define VIRTIO_TRANSPORT_F_END 38
> >
> > #ifndef VIRTIO_CONFIG_NO_LEGACY
> > /* Do we get callbacks when the ring is completely used, even if we've
>
> <snip>
>
> --
> Mark Rustad, Networking Division, Intel Corporation