lkml.org 
[lkml]   [2018]   [Feb]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH RFC 1/2] virtio: introduce packed ring defines
On Tue, Feb 27, 2018 at 09:54:58AM +0100, Jens Freimann wrote:
> On Fri, Feb 23, 2018 at 07:18:00PM +0800, Tiwei Bie wrote:
> > Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> > ---
> > include/uapi/linux/virtio_config.h | 18 +++++++++-
> > include/uapi/linux/virtio_ring.h | 68 ++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 85 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h
> > index 308e2096291f..e3d077ef5207 100644
> > --- a/include/uapi/linux/virtio_config.h
> > +++ b/include/uapi/linux/virtio_config.h
> > @@ -49,7 +49,7 @@
> > * 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 37
> >
> > #ifndef VIRTIO_CONFIG_NO_LEGACY
> > /* Do we get callbacks when the ring is completely used, even if we've
> > @@ -71,4 +71,20 @@
> > * this is for compatibility with legacy systems.
> > */
> > #define VIRTIO_F_IOMMU_PLATFORM 33
> > +
> > +/* This feature indicates support for the packed virtqueue layout. */
> > +#define VIRTIO_F_RING_PACKED 34
>
> Spec says VIRTIO_F_PACKED_RING not RING_PACKED

I changed that now :)

> > +
> > +/*
> > + * This feature indicates that all buffers are used by the device
> > + * in the same order in which they have been made available.
> > + */
> > +#define VIRTIO_F_IN_ORDER 35
> > +
> > +/*
> > + * This feature indicates that drivers pass extra data (besides
> > + * identifying the Virtqueue) in their device notifications.
> > + */
> > +#define VIRTIO_F_NOTIFICATION_DATA 36
> > +
> > #endif /* _UAPI_LINUX_VIRTIO_CONFIG_H */
> > diff --git a/include/uapi/linux/virtio_ring.h b/include/uapi/linux/virtio_ring.h
> > index 6d5d5faa989b..77b1d4aeef72 100644
> > --- a/include/uapi/linux/virtio_ring.h
> > +++ b/include/uapi/linux/virtio_ring.h
> > @@ -44,6 +44,9 @@
> > /* This means the buffer contains a list of buffer descriptors. */
> > #define VRING_DESC_F_INDIRECT 4
> >
> > +#define VRING_DESC_F_AVAIL(b) ((b) << 7)
> > +#define VRING_DESC_F_USED(b) ((b) << 15)
> > +
> > /* The Host uses this in used->flags to advise the Guest: don't kick me when
> > * you add a buffer. It's unreliable, so it's simply an optimization. Guest
> > * will still kick if it's out of buffers. */
> > @@ -104,6 +107,36 @@ struct vring {
> > struct vring_used *used;
> > };
> >
> > +struct vring_packed_desc_event {
> > + /* Descriptor Event Offset */
> > + __virtio16 desc_event_off : 15,
> > + /* Descriptor Event Wrap Counter */
> > + desc_event_wrap : 1;
> > + /* Descriptor Event Flags */
> > + __virtio16 desc_event_flags : 2;
> > +};
>
> Where would the virtqueue number go in driver notifications?
>
> regards,
> Jens

\
 
 \ /
  Last update: 2018-02-27 21:28    [W:0.238 / U:0.136 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site