Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 11:46:57AM -0500, Michael S. Tsirkin wrote: > On Sat, Dec 01, 2018 at 12:24:16AM +0800, Tiwei Bie wrote: > > On Fri, Nov 30, 2018 at 10:53:07AM -0500, Michael S. Tsirkin wrote: > > > On Fri, Nov 30, 2018 at 11:37:37PM +0800, Tiwei Bie wrote: > > > > On Fri, Nov 30, 2018 at 08:52:42AM -0500, Michael S. Tsirkin wrote: > > > > > On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > > > > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > > > > > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > > > > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > > > > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > > > > > > Add types and macros for packed ring. > > > > > > > > > > > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > > > > > > --- > > > > > > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > > > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > > > > > > ++ > > > > > > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > > > > > > b/include/uapi/linux/virtio_config.h > > > > > > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > > > > > > @@ -75,6 +75,9 @@ > > > > > > > > > > */ > > > > > > > > > >#define VIRTIO_F_IOMMU_PLATFORM 33 > > > > > > > > > > +/* This feature indicates support for the packed virtqueue > > > > > > > > > > layout. */ > > > > > > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > > > > > > + > > > > > > > > > >/* > > > > > > > > > > * Does the device support Single Root I/O > > > > > > > > > > Virtualization? > > > > > > > > > > */ > > > > > > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > > > > > > b/include/uapi/linux/virtio_ring.h > > > > > > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > > > > > > @@ -44,6 +44,13 @@ > > > > > > > > > >/* This means the buffer contains a list of buffer > > > > > > > > > > descriptors. */ > > > > > > > > > >#define VRING_DESC_F_INDIRECT4 > > > > > > > > > > +/* > > > > > > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > > > > > > + * Notice: they are defined as shifts instead of shifted > > > > > > > > > > values. > > > > > > > > > > > > > > > > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for > > > > > > > > > using shifts? > > > > > > > > > > > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > > > > > > number, not a shifted value: > > > > > > > > > > > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > > > > > > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > > > > > > > > > > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > > > > > > > > > > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > > > > > > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > > > > > > > > > > > #define VRING_DESC_F_AVAIL_SHIFT 7 > > > > > > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > > > > > > > > > > > I think it would be better for consistency. > > > > > > > > > > I don't think that will help. the problem is that > > > > > most of the existing virtio code consistently uses _F_ as shifts. > > > > > So we just need to do something about these 5 being inconsistent: > > > > > > > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 > > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 > > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 > > > > > include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 > > > > > include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT > > > > > 1 > > > > > > > > > > I do not want all of virtio to become verbose with _SHIFT, ergo > > > > > we need to change the above 5 to have names which are with _F_ and > > > > > have the bit number. > > > > > > > > How about something like this: > > > > > > > > #define VRING_COMM_DESC_F_NEXT 0 > > > > #define VRING_COMM_DESC_F_WRITE 1 > > > > #define VRING_COMM_DESC_F_INDIRECT 2 > > > > > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY0 > > > > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT0 > > > > > > > > or > > > > > > > > #define VRING_SPLIT_DESC_F_NEXT 0 > > > > #define VRING_SPLIT_DESC_F_WRITE1 > > > > #define VRING_SPLIT_DESC_F_INDIRECT 2 > > > > > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY0 > > > >
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Sat, Dec 01, 2018 at 12:24:16AM +0800, Tiwei Bie wrote: > On Fri, Nov 30, 2018 at 10:53:07AM -0500, Michael S. Tsirkin wrote: > > On Fri, Nov 30, 2018 at 11:37:37PM +0800, Tiwei Bie wrote: > > > On Fri, Nov 30, 2018 at 08:52:42AM -0500, Michael S. Tsirkin wrote: > > > > On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > > > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > > > > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > > > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > > > > > Add types and macros for packed ring. > > > > > > > > > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > > > > > --- > > > > > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > > > > > ++ > > > > > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > > > > > b/include/uapi/linux/virtio_config.h > > > > > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > > > > > @@ -75,6 +75,9 @@ > > > > > > > > > */ > > > > > > > > >#define VIRTIO_F_IOMMU_PLATFORM33 > > > > > > > > > +/* This feature indicates support for the packed virtqueue > > > > > > > > > layout. */ > > > > > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > > > > > + > > > > > > > > >/* > > > > > > > > > * Does the device support Single Root I/O Virtualization? > > > > > > > > > */ > > > > > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > > > > > b/include/uapi/linux/virtio_ring.h > > > > > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > > > > > @@ -44,6 +44,13 @@ > > > > > > > > >/* This means the buffer contains a list of buffer > > > > > > > > > descriptors. */ > > > > > > > > >#define VRING_DESC_F_INDIRECT 4 > > > > > > > > > +/* > > > > > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > > > > > + * Notice: they are defined as shifts instead of shifted > > > > > > > > > values. > > > > > > > > > > > > > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for using > > > > > > > > shifts? > > > > > > > > > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > > > > > number, not a shifted value: > > > > > > > > > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > > > > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > > > > > > > > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > > > > > > > > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > > > > > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > > > > > > > > > #define VRING_DESC_F_AVAIL_SHIFT 7 > > > > > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > > > > > > > > > I think it would be better for consistency. > > > > > > > > I don't think that will help. the problem is that > > > > most of the existing virtio code consistently uses _F_ as shifts. > > > > So we just need to do something about these 5 being inconsistent: > > > > > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 > > > > include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 > > > > include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT > > > > 1 > > > > > > > > I do not want all of virtio to become verbose with _SHIFT, ergo > > > > we need to change the above 5 to have names which are with _F_ and > > > > have the bit number. > > > > > > How about something like this: > > > > > > #define VRING_COMM_DESC_F_NEXT0 > > > #define VRING_COMM_DESC_F_WRITE 1 > > > #define VRING_COMM_DESC_F_INDIRECT2 > > > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY 0 > > > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT 0 > > > > > > or > > > > > > #define VRING_SPLIT_DESC_F_NEXT 0 > > > #define VRING_SPLIT_DESC_F_WRITE 1 > > > #define VRING_SPLIT_DESC_F_INDIRECT 2 > > > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY 0 > > > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT 0 > > > > > > #define VRING_PACKED_DESC_F_NEXT 0 > > > #define VRING_PACKED_DESC_F_WRITE 1 > > > #define VRING_PACKED_DESC_F_INDIRECT 2 > > > > As we aren't sharing code I think I prefer the second form. > > Maybe add
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 10:53:07AM -0500, Michael S. Tsirkin wrote: > On Fri, Nov 30, 2018 at 11:37:37PM +0800, Tiwei Bie wrote: > > On Fri, Nov 30, 2018 at 08:52:42AM -0500, Michael S. Tsirkin wrote: > > > On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > > > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > > > > Add types and macros for packed ring. > > > > > > > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > > > > --- > > > > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > > > > ++ > > > > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > > > > b/include/uapi/linux/virtio_config.h > > > > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > > > > @@ -75,6 +75,9 @@ > > > > > > > > */ > > > > > > > >#define VIRTIO_F_IOMMU_PLATFORM 33 > > > > > > > > +/* This feature indicates support for the packed virtqueue > > > > > > > > layout. */ > > > > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > > > > + > > > > > > > >/* > > > > > > > > * Does the device support Single Root I/O Virtualization? > > > > > > > > */ > > > > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > > > > b/include/uapi/linux/virtio_ring.h > > > > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > > > > @@ -44,6 +44,13 @@ > > > > > > > >/* This means the buffer contains a list of buffer > > > > > > > > descriptors. */ > > > > > > > >#define VRING_DESC_F_INDIRECT4 > > > > > > > > +/* > > > > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > > > > + * Notice: they are defined as shifts instead of shifted > > > > > > > > values. > > > > > > > > > > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for using > > > > > > > shifts? > > > > > > > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > > > > number, not a shifted value: > > > > > > > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > > > > > > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > > > > > > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > > > > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > > > > > > > #define VRING_DESC_F_AVAIL_SHIFT 7 > > > > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > > > > > > > I think it would be better for consistency. > > > > > > I don't think that will help. the problem is that > > > most of the existing virtio code consistently uses _F_ as shifts. > > > So we just need to do something about these 5 being inconsistent: > > > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 > > > include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 > > > include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT 1 > > > > > > I do not want all of virtio to become verbose with _SHIFT, ergo > > > we need to change the above 5 to have names which are with _F_ and > > > have the bit number. > > > > How about something like this: > > > > #define VRING_COMM_DESC_F_NEXT 0 > > #define VRING_COMM_DESC_F_WRITE 1 > > #define VRING_COMM_DESC_F_INDIRECT 2 > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY0 > > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT0 > > > > or > > > > #define VRING_SPLIT_DESC_F_NEXT 0 > > #define VRING_SPLIT_DESC_F_WRITE1 > > #define VRING_SPLIT_DESC_F_INDIRECT 2 > > > > #define VRING_SPLIT_USED_F_NO_NOTIFY0 > > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT0 > > > > #define VRING_PACKED_DESC_F_NEXT0 > > #define VRING_PACKED_DESC_F_WRITE 1 > > #define VRING_PACKED_DESC_F_INDIRECT2 > > As we aren't sharing code I think I prefer the second form. > Maybe add VRING_NO_LEGACY so people can audit their code > for assumptions? Maybe it's better to name it as VIRTIO_RING_NO_LEGACY which is more consistent with the names in other files. > > We also want to guard layout definitions at the end of that file > I think. Do you
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 11:37:37PM +0800, Tiwei Bie wrote: > On Fri, Nov 30, 2018 at 08:52:42AM -0500, Michael S. Tsirkin wrote: > > On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > > > Add types and macros for packed ring. > > > > > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > > > --- > > > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > > > ++ > > > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > > > b/include/uapi/linux/virtio_config.h > > > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > > > @@ -75,6 +75,9 @@ > > > > > > > */ > > > > > > >#define VIRTIO_F_IOMMU_PLATFORM33 > > > > > > > +/* This feature indicates support for the packed virtqueue > > > > > > > layout. */ > > > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > > > + > > > > > > >/* > > > > > > > * Does the device support Single Root I/O Virtualization? > > > > > > > */ > > > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > > > b/include/uapi/linux/virtio_ring.h > > > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > > > @@ -44,6 +44,13 @@ > > > > > > >/* This means the buffer contains a list of buffer > > > > > > > descriptors. */ > > > > > > >#define VRING_DESC_F_INDIRECT 4 > > > > > > > +/* > > > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > > > + * Notice: they are defined as shifts instead of shifted values. > > > > > > > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for using > > > > > > shifts? > > > > > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > > > number, not a shifted value: > > > > > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > > > > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > > > > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > > > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > > > > > #define VRING_DESC_F_AVAIL_SHIFT 7 > > > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > > > > > I think it would be better for consistency. > > > > I don't think that will help. the problem is that > > most of the existing virtio code consistently uses _F_ as shifts. > > So we just need to do something about these 5 being inconsistent: > > > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 > > include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 > > include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT 1 > > > > I do not want all of virtio to become verbose with _SHIFT, ergo > > we need to change the above 5 to have names which are with _F_ and > > have the bit number. > > How about something like this: > > #define VRING_COMM_DESC_F_NEXT0 > #define VRING_COMM_DESC_F_WRITE 1 > #define VRING_COMM_DESC_F_INDIRECT2 > > #define VRING_SPLIT_USED_F_NO_NOTIFY 0 > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT 0 > > or > > #define VRING_SPLIT_DESC_F_NEXT 0 > #define VRING_SPLIT_DESC_F_WRITE 1 > #define VRING_SPLIT_DESC_F_INDIRECT 2 > > #define VRING_SPLIT_USED_F_NO_NOTIFY 0 > #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT 0 > > #define VRING_PACKED_DESC_F_NEXT 0 > #define VRING_PACKED_DESC_F_WRITE 1 > #define VRING_PACKED_DESC_F_INDIRECT 2 As we aren't sharing code I think I prefer the second form. Maybe add VRING_NO_LEGACY so people can audit their code for assumptions? We also want to guard layout definitions at the end of that file I think. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > + */ > > > > > > > +#define VRING_PACKED_DESC_F_AVAIL7 > > > > > > > +#define VRING_PACKED_DESC_F_USED 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.
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 08:52:42AM -0500, Michael S. Tsirkin wrote: > On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > > Add types and macros for packed ring. > > > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > > --- > > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > > ++ > > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > > b/include/uapi/linux/virtio_config.h > > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > > @@ -75,6 +75,9 @@ > > > > > > */ > > > > > >#define VIRTIO_F_IOMMU_PLATFORM 33 > > > > > > +/* This feature indicates support for the packed virtqueue layout. > > > > > > */ > > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > > + > > > > > >/* > > > > > > * Does the device support Single Root I/O Virtualization? > > > > > > */ > > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > > b/include/uapi/linux/virtio_ring.h > > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > > @@ -44,6 +44,13 @@ > > > > > >/* This means the buffer contains a list of buffer descriptors. > > > > > > */ > > > > > >#define VRING_DESC_F_INDIRECT4 > > > > > > +/* > > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > > + * Notice: they are defined as shifts instead of shifted values. > > > > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for using > > > > > shifts? > > > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > > number, not a shifted value: > > > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > > > #define VRING_DESC_F_AVAIL_SHIFT 7 > > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > > > I think it would be better for consistency. > > I don't think that will help. the problem is that > most of the existing virtio code consistently uses _F_ as shifts. > So we just need to do something about these 5 being inconsistent: > > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 > include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 > include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 > include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT 1 > > I do not want all of virtio to become verbose with _SHIFT, ergo > we need to change the above 5 to have names which are with _F_ and > have the bit number. How about something like this: #define VRING_COMM_DESC_F_NEXT 0 #define VRING_COMM_DESC_F_WRITE 1 #define VRING_COMM_DESC_F_INDIRECT 2 #define VRING_SPLIT_USED_F_NO_NOTIFY0 #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT0 or #define VRING_SPLIT_DESC_F_NEXT 0 #define VRING_SPLIT_DESC_F_WRITE1 #define VRING_SPLIT_DESC_F_INDIRECT 2 #define VRING_SPLIT_USED_F_NO_NOTIFY0 #define VRING_SPLIT_AVAIL_F_NO_INTERRUPT0 #define VRING_PACKED_DESC_F_NEXT0 #define VRING_PACKED_DESC_F_WRITE 1 #define VRING_PACKED_DESC_F_INDIRECT2 > > > > > > > > > > > > > > > > > > > > > > > > > + */ > > > > > > +#define VRING_PACKED_DESC_F_AVAIL 7 > > > > > > +#define VRING_PACKED_DESC_F_USED 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. */ > > > > > > @@ -53,6 +60,23 @@ > > > > > > * optimization. */ > > > > > >#define VRING_AVAIL_F_NO_INTERRUPT 1 > > > > > > +/* Enable events in packed ring. */ > > > > > > +#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0 > > > > > > +/* Disable events in packed ring. */ > > > > > > +#define VRING_PACKED_EVENT_FLAG_DISABLE0x1 > > > > > > +/* > > > > > > + * Enable events for a specific descriptor in packed ring. > > > >
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 02:01:06PM +0100, Maxime Coquelin wrote: > > > On 11/30/18 1:47 PM, Michael S. Tsirkin wrote: > > On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote: > > > On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote: > > > > > > > > On 2018/11/21 下午6:03, Tiwei Bie wrote: > > > > > Add types and macros for packed ring. > > > > > > > > > > Signed-off-by: Tiwei Bie > > > > > --- > > > > >include/uapi/linux/virtio_config.h | 3 +++ > > > > >include/uapi/linux/virtio_ring.h | 52 > > > > > ++ > > > > >2 files changed, 55 insertions(+) > > > > > > > > > > diff --git a/include/uapi/linux/virtio_config.h > > > > > b/include/uapi/linux/virtio_config.h > > > > > index 449132c76b1c..1196e1c1d4f6 100644 > > > > > --- a/include/uapi/linux/virtio_config.h > > > > > +++ b/include/uapi/linux/virtio_config.h > > > > > @@ -75,6 +75,9 @@ > > > > > */ > > > > >#define VIRTIO_F_IOMMU_PLATFORM33 > > > > > +/* This feature indicates support for the packed virtqueue layout. */ > > > > > +#define VIRTIO_F_RING_PACKED 34 > > > > > + > > > > >/* > > > > > * Does the device support Single Root I/O Virtualization? > > > > > */ > > > > > diff --git a/include/uapi/linux/virtio_ring.h > > > > > b/include/uapi/linux/virtio_ring.h > > > > > index 6d5d5faa989b..2414f8af26b3 100644 > > > > > --- a/include/uapi/linux/virtio_ring.h > > > > > +++ b/include/uapi/linux/virtio_ring.h > > > > > @@ -44,6 +44,13 @@ > > > > >/* This means the buffer contains a list of buffer descriptors. */ > > > > >#define VRING_DESC_F_INDIRECT 4 > > > > > +/* > > > > > + * Mark a descriptor as available or used in packed ring. > > > > > + * Notice: they are defined as shifts instead of shifted values. > > > > > > > > > > > > This looks inconsistent to previous flags, any reason for using shifts? > > > > > > Yeah, it was suggested to use shifts, as _F_ should be a bit > > > number, not a shifted value: > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > But let's add a _SPLIT_ variant that uses shifts consistently. > > Maybe we could avoid adding SPLIT and PACKED, but define as follow: > > #define VRING_DESC_F_INDIRECT_SHIFT 2 > #define VRING_DESC_F_INDIRECT (1ull << VRING_DESC_F_INDIRECT_SHIFT) > > #define VRING_DESC_F_AVAIL_SHIFT 7 > #define VRING_DESC_F_AVAIL (1ull << VRING_DESC_F_AVAIL_SHIFT) > > I think it would be better for consistency. I don't think that will help. the problem is that most of the existing virtio code consistently uses _F_ as shifts. So we just need to do something about these 5 being inconsistent: include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_NEXT 1 include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_WRITE 2 include/uapi/linux/virtio_ring.h:#define VRING_DESC_F_INDIRECT 4 include/uapi/linux/virtio_ring.h:#define VRING_USED_F_NO_NOTIFY 1 include/uapi/linux/virtio_ring.h:#define VRING_AVAIL_F_NO_INTERRUPT 1 I do not want all of virtio to become verbose with _SHIFT, ergo we need to change the above 5 to have names which are with _F_ and have the bit number. > > > > > > > > > > > > > > > > > + */ > > > > > +#define VRING_PACKED_DESC_F_AVAIL7 > > > > > +#define VRING_PACKED_DESC_F_USED 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. */ > > > > > @@ -53,6 +60,23 @@ > > > > > * optimization. */ > > > > >#define VRING_AVAIL_F_NO_INTERRUPT 1 > > > > > +/* Enable events in packed ring. */ > > > > > +#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0 > > > > > +/* Disable events in packed ring. */ > > > > > +#define VRING_PACKED_EVENT_FLAG_DISABLE 0x1 > > > > > +/* > > > > > + * Enable events for a specific descriptor in packed ring. > > > > > + * (as specified by Descriptor Ring Change Event Offset/Wrap > > > > > Counter). > > > > > + * Only valid if VIRTIO_RING_F_EVENT_IDX has been negotiated. > > > > > + */ > > > > > +#define VRING_PACKED_EVENT_FLAG_DESC 0x2 > > > > > > > > > > > > Any reason for using _FLAG_ instead of _F_? > > > > > > Yeah, it was suggested to not use _F_, as these are values, > > > should not have _F_: > > > > > > https://patchwork.ozlabs.org/patch/942296/#1989390 > > > > > > Regards, > > > Tiwei > > > > > > > > > > > Thanks > > > > > > > > > > > > > + > > > > > +/* > > > > > + * Wrap counter bit shift in event suppression structure > > > > > + * of packed ring. > > > > > + */ > > > > > +#define VRING_PACKED_EVENT_F_WRAP_CTR15 > > > > > + > > > > >/* We support indirect buffer descriptors */ > > > > >#define VIRTIO_RING_F_INDIRECT_DESC28 > > > > > @@ -171,4 +195,32 @@ static inline int vring_need_event(__u16 > > > > > event_idx, __u16 new_idx, __u16 old)
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 05:53:40PM +0800, Tiwei Bie wrote:
> On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote:
> >
> > On 2018/11/21 下午6:03, Tiwei Bie wrote:
> > > Add types and macros for packed ring.
> > >
> > > Signed-off-by: Tiwei Bie
> > > ---
> > > include/uapi/linux/virtio_config.h | 3 +++
> > > include/uapi/linux/virtio_ring.h | 52
> > > ++
> > > 2 files changed, 55 insertions(+)
> > >
> > > diff --git a/include/uapi/linux/virtio_config.h
> > > b/include/uapi/linux/virtio_config.h
> > > index 449132c76b1c..1196e1c1d4f6 100644
> > > --- a/include/uapi/linux/virtio_config.h
> > > +++ b/include/uapi/linux/virtio_config.h
> > > @@ -75,6 +75,9 @@
> > >*/
> > > #define VIRTIO_F_IOMMU_PLATFORM 33
> > > +/* This feature indicates support for the packed virtqueue layout. */
> > > +#define VIRTIO_F_RING_PACKED 34
> > > +
> > > /*
> > >* Does the device support Single Root I/O Virtualization?
> > >*/
> > > diff --git a/include/uapi/linux/virtio_ring.h
> > > b/include/uapi/linux/virtio_ring.h
> > > index 6d5d5faa989b..2414f8af26b3 100644
> > > --- a/include/uapi/linux/virtio_ring.h
> > > +++ b/include/uapi/linux/virtio_ring.h
> > > @@ -44,6 +44,13 @@
> > > /* This means the buffer contains a list of buffer descriptors. */
> > > #define VRING_DESC_F_INDIRECT 4
> > > +/*
> > > + * Mark a descriptor as available or used in packed ring.
> > > + * Notice: they are defined as shifts instead of shifted values.
> >
> >
> > This looks inconsistent to previous flags, any reason for using shifts?
>
> Yeah, it was suggested to use shifts, as _F_ should be a bit
> number, not a shifted value:
>
> https://patchwork.ozlabs.org/patch/942296/#1989390
But let's add a _SPLIT_ variant that uses shifts consistently.
> >
> >
> > > + */
> > > +#define VRING_PACKED_DESC_F_AVAIL7
> > > +#define VRING_PACKED_DESC_F_USED 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. */
> > > @@ -53,6 +60,23 @@
> > >* optimization. */
> > > #define VRING_AVAIL_F_NO_INTERRUPT 1
> > > +/* Enable events in packed ring. */
> > > +#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0
> > > +/* Disable events in packed ring. */
> > > +#define VRING_PACKED_EVENT_FLAG_DISABLE 0x1
> > > +/*
> > > + * Enable events for a specific descriptor in packed ring.
> > > + * (as specified by Descriptor Ring Change Event Offset/Wrap Counter).
> > > + * Only valid if VIRTIO_RING_F_EVENT_IDX has been negotiated.
> > > + */
> > > +#define VRING_PACKED_EVENT_FLAG_DESC 0x2
> >
> >
> > Any reason for using _FLAG_ instead of _F_?
>
> Yeah, it was suggested to not use _F_, as these are values,
> should not have _F_:
>
> https://patchwork.ozlabs.org/patch/942296/#1989390
>
> Regards,
> Tiwei
>
> >
> > Thanks
> >
> >
> > > +
> > > +/*
> > > + * Wrap counter bit shift in event suppression structure
> > > + * of packed ring.
> > > + */
> > > +#define VRING_PACKED_EVENT_F_WRAP_CTR15
> > > +
> > > /* We support indirect buffer descriptors */
> > > #define VIRTIO_RING_F_INDIRECT_DESC 28
> > > @@ -171,4 +195,32 @@ static inline int vring_need_event(__u16 event_idx,
> > > __u16 new_idx, __u16 old)
> > > return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx -
> > > old);
> > > }
> > > +struct vring_packed_desc_event {
> > > + /* Descriptor Ring Change Event Offset/Wrap Counter. */
> > > + __le16 off_wrap;
> > > + /* Descriptor Ring Change Event Flags. */
> > > + __le16 flags;
> > > +};
> > > +
> > > +struct vring_packed_desc {
> > > + /* Buffer Address. */
> > > + __le64 addr;
> > > + /* Buffer Length. */
> > > + __le32 len;
> > > + /* Buffer ID. */
> > > + __le16 id;
> > > + /* The flags depending on descriptor type. */
> > > + __le16 flags;
> > > +};
> > > +
> > > +struct vring_packed {
> > > + unsigned int num;
> > > +
> > > + struct vring_packed_desc *desc;
> > > +
> > > + struct vring_packed_desc_event *driver;
> > > +
> > > + struct vring_packed_desc_event *device;
> > > +};
> > > +
> > > #endif /* _UAPI_LINUX_VIRTIO_RING_H */
___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On Fri, Nov 30, 2018 at 04:10:55PM +0800, Jason Wang wrote:
>
> On 2018/11/21 下午6:03, Tiwei Bie wrote:
> > Add types and macros for packed ring.
> >
> > Signed-off-by: Tiwei Bie
> > ---
> > include/uapi/linux/virtio_config.h | 3 +++
> > include/uapi/linux/virtio_ring.h | 52
> > ++
> > 2 files changed, 55 insertions(+)
> >
> > diff --git a/include/uapi/linux/virtio_config.h
> > b/include/uapi/linux/virtio_config.h
> > index 449132c76b1c..1196e1c1d4f6 100644
> > --- a/include/uapi/linux/virtio_config.h
> > +++ b/include/uapi/linux/virtio_config.h
> > @@ -75,6 +75,9 @@
> >*/
> > #define VIRTIO_F_IOMMU_PLATFORM 33
> > +/* This feature indicates support for the packed virtqueue layout. */
> > +#define VIRTIO_F_RING_PACKED 34
> > +
> > /*
> >* Does the device support Single Root I/O Virtualization?
> >*/
> > diff --git a/include/uapi/linux/virtio_ring.h
> > b/include/uapi/linux/virtio_ring.h
> > index 6d5d5faa989b..2414f8af26b3 100644
> > --- a/include/uapi/linux/virtio_ring.h
> > +++ b/include/uapi/linux/virtio_ring.h
> > @@ -44,6 +44,13 @@
> > /* This means the buffer contains a list of buffer descriptors. */
> > #define VRING_DESC_F_INDIRECT 4
> > +/*
> > + * Mark a descriptor as available or used in packed ring.
> > + * Notice: they are defined as shifts instead of shifted values.
>
>
> This looks inconsistent to previous flags, any reason for using shifts?
Yeah, it was suggested to use shifts, as _F_ should be a bit
number, not a shifted value:
https://patchwork.ozlabs.org/patch/942296/#1989390
>
>
> > + */
> > +#define VRING_PACKED_DESC_F_AVAIL 7
> > +#define VRING_PACKED_DESC_F_USED 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. */
> > @@ -53,6 +60,23 @@
> >* optimization. */
> > #define VRING_AVAIL_F_NO_INTERRUPT1
> > +/* Enable events in packed ring. */
> > +#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0
> > +/* Disable events in packed ring. */
> > +#define VRING_PACKED_EVENT_FLAG_DISABLE0x1
> > +/*
> > + * Enable events for a specific descriptor in packed ring.
> > + * (as specified by Descriptor Ring Change Event Offset/Wrap Counter).
> > + * Only valid if VIRTIO_RING_F_EVENT_IDX has been negotiated.
> > + */
> > +#define VRING_PACKED_EVENT_FLAG_DESC 0x2
>
>
> Any reason for using _FLAG_ instead of _F_?
Yeah, it was suggested to not use _F_, as these are values,
should not have _F_:
https://patchwork.ozlabs.org/patch/942296/#1989390
Regards,
Tiwei
>
> Thanks
>
>
> > +
> > +/*
> > + * Wrap counter bit shift in event suppression structure
> > + * of packed ring.
> > + */
> > +#define VRING_PACKED_EVENT_F_WRAP_CTR 15
> > +
> > /* We support indirect buffer descriptors */
> > #define VIRTIO_RING_F_INDIRECT_DESC 28
> > @@ -171,4 +195,32 @@ static inline int vring_need_event(__u16 event_idx,
> > __u16 new_idx, __u16 old)
> > return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old);
> > }
> > +struct vring_packed_desc_event {
> > + /* Descriptor Ring Change Event Offset/Wrap Counter. */
> > + __le16 off_wrap;
> > + /* Descriptor Ring Change Event Flags. */
> > + __le16 flags;
> > +};
> > +
> > +struct vring_packed_desc {
> > + /* Buffer Address. */
> > + __le64 addr;
> > + /* Buffer Length. */
> > + __le32 len;
> > + /* Buffer ID. */
> > + __le16 id;
> > + /* The flags depending on descriptor type. */
> > + __le16 flags;
> > +};
> > +
> > +struct vring_packed {
> > + unsigned int num;
> > +
> > + struct vring_packed_desc *desc;
> > +
> > + struct vring_packed_desc_event *driver;
> > +
> > + struct vring_packed_desc_event *device;
> > +};
> > +
> > #endif /* _UAPI_LINUX_VIRTIO_RING_H */
___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH net-next v3 01/13] virtio: add packed ring types and macros
On 2018/11/21 下午6:03, Tiwei Bie wrote:
Add types and macros for packed ring.
Signed-off-by: Tiwei Bie
---
include/uapi/linux/virtio_config.h | 3 +++
include/uapi/linux/virtio_ring.h | 52 ++
2 files changed, 55 insertions(+)
diff --git a/include/uapi/linux/virtio_config.h
b/include/uapi/linux/virtio_config.h
index 449132c76b1c..1196e1c1d4f6 100644
--- a/include/uapi/linux/virtio_config.h
+++ b/include/uapi/linux/virtio_config.h
@@ -75,6 +75,9 @@
*/
#define VIRTIO_F_IOMMU_PLATFORM 33
+/* This feature indicates support for the packed virtqueue layout. */
+#define VIRTIO_F_RING_PACKED 34
+
/*
* Does the device support Single Root I/O Virtualization?
*/
diff --git a/include/uapi/linux/virtio_ring.h b/include/uapi/linux/virtio_ring.h
index 6d5d5faa989b..2414f8af26b3 100644
--- a/include/uapi/linux/virtio_ring.h
+++ b/include/uapi/linux/virtio_ring.h
@@ -44,6 +44,13 @@
/* This means the buffer contains a list of buffer descriptors. */
#define VRING_DESC_F_INDIRECT 4
+/*
+ * Mark a descriptor as available or used in packed ring.
+ * Notice: they are defined as shifts instead of shifted values.
This looks inconsistent to previous flags, any reason for using shifts?
+ */
+#define VRING_PACKED_DESC_F_AVAIL 7
+#define VRING_PACKED_DESC_F_USED 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. */
@@ -53,6 +60,23 @@
* optimization. */
#define VRING_AVAIL_F_NO_INTERRUPT1
+/* Enable events in packed ring. */
+#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0
+/* Disable events in packed ring. */
+#define VRING_PACKED_EVENT_FLAG_DISABLE0x1
+/*
+ * Enable events for a specific descriptor in packed ring.
+ * (as specified by Descriptor Ring Change Event Offset/Wrap Counter).
+ * Only valid if VIRTIO_RING_F_EVENT_IDX has been negotiated.
+ */
+#define VRING_PACKED_EVENT_FLAG_DESC 0x2
Any reason for using _FLAG_ instead of _F_?
Thanks
+
+/*
+ * Wrap counter bit shift in event suppression structure
+ * of packed ring.
+ */
+#define VRING_PACKED_EVENT_F_WRAP_CTR 15
+
/* We support indirect buffer descriptors */
#define VIRTIO_RING_F_INDIRECT_DESC 28
@@ -171,4 +195,32 @@ static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old)
return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old);
}
+struct vring_packed_desc_event {
+ /* Descriptor Ring Change Event Offset/Wrap Counter. */
+ __le16 off_wrap;
+ /* Descriptor Ring Change Event Flags. */
+ __le16 flags;
+};
+
+struct vring_packed_desc {
+ /* Buffer Address. */
+ __le64 addr;
+ /* Buffer Length. */
+ __le32 len;
+ /* Buffer ID. */
+ __le16 id;
+ /* The flags depending on descriptor type. */
+ __le16 flags;
+};
+
+struct vring_packed {
+ unsigned int num;
+
+ struct vring_packed_desc *desc;
+
+ struct vring_packed_desc_event *driver;
+
+ struct vring_packed_desc_event *device;
+};
+
#endif /* _UAPI_LINUX_VIRTIO_RING_H */
___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH net-next v3 01/13] virtio: add packed ring types and macros
Add types and macros for packed ring.
Signed-off-by: Tiwei Bie
---
include/uapi/linux/virtio_config.h | 3 +++
include/uapi/linux/virtio_ring.h | 52 ++
2 files changed, 55 insertions(+)
diff --git a/include/uapi/linux/virtio_config.h
b/include/uapi/linux/virtio_config.h
index 449132c76b1c..1196e1c1d4f6 100644
--- a/include/uapi/linux/virtio_config.h
+++ b/include/uapi/linux/virtio_config.h
@@ -75,6 +75,9 @@
*/
#define VIRTIO_F_IOMMU_PLATFORM33
+/* This feature indicates support for the packed virtqueue layout. */
+#define VIRTIO_F_RING_PACKED 34
+
/*
* Does the device support Single Root I/O Virtualization?
*/
diff --git a/include/uapi/linux/virtio_ring.h b/include/uapi/linux/virtio_ring.h
index 6d5d5faa989b..2414f8af26b3 100644
--- a/include/uapi/linux/virtio_ring.h
+++ b/include/uapi/linux/virtio_ring.h
@@ -44,6 +44,13 @@
/* This means the buffer contains a list of buffer descriptors. */
#define VRING_DESC_F_INDIRECT 4
+/*
+ * Mark a descriptor as available or used in packed ring.
+ * Notice: they are defined as shifts instead of shifted values.
+ */
+#define VRING_PACKED_DESC_F_AVAIL 7
+#define VRING_PACKED_DESC_F_USED 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. */
@@ -53,6 +60,23 @@
* optimization. */
#define VRING_AVAIL_F_NO_INTERRUPT 1
+/* Enable events in packed ring. */
+#define VRING_PACKED_EVENT_FLAG_ENABLE 0x0
+/* Disable events in packed ring. */
+#define VRING_PACKED_EVENT_FLAG_DISABLE0x1
+/*
+ * Enable events for a specific descriptor in packed ring.
+ * (as specified by Descriptor Ring Change Event Offset/Wrap Counter).
+ * Only valid if VIRTIO_RING_F_EVENT_IDX has been negotiated.
+ */
+#define VRING_PACKED_EVENT_FLAG_DESC 0x2
+
+/*
+ * Wrap counter bit shift in event suppression structure
+ * of packed ring.
+ */
+#define VRING_PACKED_EVENT_F_WRAP_CTR 15
+
/* We support indirect buffer descriptors */
#define VIRTIO_RING_F_INDIRECT_DESC28
@@ -171,4 +195,32 @@ static inline int vring_need_event(__u16 event_idx, __u16
new_idx, __u16 old)
return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old);
}
+struct vring_packed_desc_event {
+ /* Descriptor Ring Change Event Offset/Wrap Counter. */
+ __le16 off_wrap;
+ /* Descriptor Ring Change Event Flags. */
+ __le16 flags;
+};
+
+struct vring_packed_desc {
+ /* Buffer Address. */
+ __le64 addr;
+ /* Buffer Length. */
+ __le32 len;
+ /* Buffer ID. */
+ __le16 id;
+ /* The flags depending on descriptor type. */
+ __le16 flags;
+};
+
+struct vring_packed {
+ unsigned int num;
+
+ struct vring_packed_desc *desc;
+
+ struct vring_packed_desc_event *driver;
+
+ struct vring_packed_desc_event *device;
+};
+
#endif /* _UAPI_LINUX_VIRTIO_RING_H */
--
2.14.5
___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
