[PATCH v3 2/3] xen/arm: reimplement xen_dma_unmap_page & friends

[Wei Liu]

On Fri, Aug 08, 2014 at 03:49:26PM +0100, Thomas Leonard wrote:
> On 8 August 2014 15:38, Wei Liu <wei.liu2 at citrix.com> wrote:
> > On Fri, Aug 08, 2014 at 03:32:41PM +0100, Stefano Stabellini wrote:
> >> On Fri, 1 Aug 2014, Stefano Stabellini wrote:
> >> > +static void __xen_dma_page_dev_to_cpu(struct device *hwdev, dma_addr_t handle,
> >> > +           size_t size, enum dma_data_direction dir)
> >> > +{
> >> > +   /* Cannot use __dma_page_dev_to_cpu because we don't have a
> >> > +    * struct page for handle */
> >> > +
> >> > +   if (dir == DMA_TO_DEVICE)
> >>
> >> This should be:
> >>     if (dir != DMA_TO_DEVICE)
> >>
> >> Thomas, could you please confirm that with this small fix
> >> http://pastebin.com/FPRf7pgL goes away?
> >>
> >
> > Thomas, please try this fix with my ref-counting patch.
> >
> > The old "working" version might actually cover this latent bug due to
> > it's long delay.
> 
> I'm not sure how to apply this. The function
> "__xen_dma_page_dev_to_cpu" doesn't appear in your "for-thomas"
> branch. If you push the change to that branch I can test it.
> 

I think you can cherry-pick my three patches to your tree which contains
Stefano's patches. It's probably easier because Stefano's patches are
not yet in mainline while my patches should be able to apply to 3.16
mainline kernel without much effort.

I've rebased my patches on top of 3.16, in for-thomas2 branch.

Wei.

> > Wei.
> >
> >>
> >> > +           outer_inv_range(handle, handle + size);
> >> > +
> >> > +   dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, dmac_unmap_area);
> >> > +}
> 
> 
> 
> -- 
> Dr Thomas Leonard        http://0install.net/
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