Displaying 7 results from an estimated 7 matches for "alloc_someth".
2018 Aug 02
4
[RFC 0/4] Virtio uses DMA API for all devices
...if we are to switch to
> PLATFORM_IOMMU by default. We need to fix that.
So let's differenciate the two problems of having an IOMMU (real or
emulated) which indeeds adds overhead etc... and using the DMA API.
At the moment, virtio does this all over the place:
if (use_dma_api)
dma_map/alloc_something(...)
else
use_pa
The idea of the patch set is to do two, somewhat orthogonal, changes
that together achieve what we want. Let me know where you think there
is "a bunch of issues" because I'm missing it:
1- Replace the above if/else constructs with just calling the DMA API,
an...
2018 Aug 02
4
[RFC 0/4] Virtio uses DMA API for all devices
...if we are to switch to
> PLATFORM_IOMMU by default. We need to fix that.
So let's differenciate the two problems of having an IOMMU (real or
emulated) which indeeds adds overhead etc... and using the DMA API.
At the moment, virtio does this all over the place:
if (use_dma_api)
dma_map/alloc_something(...)
else
use_pa
The idea of the patch set is to do two, somewhat orthogonal, changes
that together achieve what we want. Let me know where you think there
is "a bunch of issues" because I'm missing it:
1- Replace the above if/else constructs with just calling the DMA API,
an...
2018 Aug 03
0
[RFC 0/4] Virtio uses DMA API for all devices
...:09PM -0500, Benjamin Herrenschmidt wrote:
> So let's differenciate the two problems of having an IOMMU (real or
> emulated) which indeeds adds overhead etc... and using the DMA API.
>
> At the moment, virtio does this all over the place:
>
> if (use_dma_api)
> dma_map/alloc_something(...)
> else
> use_pa
>
> The idea of the patch set is to do two, somewhat orthogonal, changes
> that together achieve what we want. Let me know where you think there
> is "a bunch of issues" because I'm missing it:
>
> 1- Replace the above if/else cons...
2018 Aug 03
3
[RFC 0/4] Virtio uses DMA API for all devices
...wrote:
> > So let's differenciate the two problems of having an IOMMU (real or
> > emulated) which indeeds adds overhead etc... and using the DMA API.
> >
> > At the moment, virtio does this all over the place:
> >
> > if (use_dma_api)
> > dma_map/alloc_something(...)
> > else
> > use_pa
> >
> > The idea of the patch set is to do two, somewhat orthogonal, changes
> > that together achieve what we want. Let me know where you think there
> > is "a bunch of issues" because I'm missing it:
> >
>...
2018 Aug 03
3
[RFC 0/4] Virtio uses DMA API for all devices
...wrote:
> > So let's differenciate the two problems of having an IOMMU (real or
> > emulated) which indeeds adds overhead etc... and using the DMA API.
> >
> > At the moment, virtio does this all over the place:
> >
> > if (use_dma_api)
> > dma_map/alloc_something(...)
> > else
> > use_pa
> >
> > The idea of the patch set is to do two, somewhat orthogonal, changes
> > that together achieve what we want. Let me know where you think there
> > is "a bunch of issues" because I'm missing it:
> >
>...
2018 Aug 02
2
[RFC 0/4] Virtio uses DMA API for all devices
On Thu, 2018-08-02 at 20:19 +0300, Michael S. Tsirkin wrote:
>
> I see. So yes, given that device does not know or care, using
> virtio features is an awkward fit.
>
> So let's say as a quick fix for you maybe we could generalize the
> xen_domain hack, instead of just checking xen_domain check some static
> branch. Then teach xen and others to enable that.>
> OK
2018 Aug 02
2
[RFC 0/4] Virtio uses DMA API for all devices
On Thu, 2018-08-02 at 20:19 +0300, Michael S. Tsirkin wrote:
>
> I see. So yes, given that device does not know or care, using
> virtio features is an awkward fit.
>
> So let's say as a quick fix for you maybe we could generalize the
> xen_domain hack, instead of just checking xen_domain check some static
> branch. Then teach xen and others to enable that.>
> OK