Tom Murphy
2020-Aug-27 23:34 UTC
[PATCH 0/8] Convert the intel iommu driver to the dma-iommu api
On Thu, 27 Aug 2020 at 22:36, Logan Gunthorpe <logang at deltatee.com> wrote:> > > > On 2020-08-23 6:04 p.m., Tom Murphy wrote: > > I have added a check for the sg_dma_len == 0 : > > """ > > } __sgt_iter(struct scatterlist *sgl, bool dma) { > > struct sgt_iter s = { .sgp = sgl }; > > > > + if (sgl && sg_dma_len(sgl) == 0) > > + s.sgp = NULL; > > > > if (s.sgp) { > > ..... > > """ > > at location [1]. > > but it doens't fix the problem. > > Based on my read of the code, it looks like we also need to change usage > of sgl->length... Something like the rough patch below, maybe? > > Also, Tom, do you have an updated version of the patchset to convert the > Intel IOMMU to dma-iommu available? The last one I've found doesn't > apply cleanly (I'm assuming parts of it have been merged in slightly > modified forms). >I'll try and post one in the next 24hours> Thanks, > > Logan > > -- > > diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h > b/drivers/gpu/drm/i915/i915 > index b7b59328cb76..9367ac801f0c 100644 > --- a/drivers/gpu/drm/i915/i915_scatterlist.h > +++ b/drivers/gpu/drm/i915/i915_scatterlist.h > @@ -27,13 +27,19 @@ static __always_inline struct sgt_iter { > } __sgt_iter(struct scatterlist *sgl, bool dma) { > struct sgt_iter s = { .sgp = sgl }; > > + if (sgl && !sg_dma_len(s.sgp)) > + s.sgp = NULL; > + > if (s.sgp) { > s.max = s.curr = s.sgp->offset; > - s.max += s.sgp->length; > - if (dma) > + > + if (dma) { > + s.max += sg_dma_len(s.sgp); > s.dma = sg_dma_address(s.sgp); > - else > + } else { > + s.max += s.sgp->length; > s.pfn = page_to_pfn(sg_page(s.sgp)); > + } > } > > return s;
Tom Murphy
2020-Sep-03 20:26 UTC
[PATCH 0/8] Convert the intel iommu driver to the dma-iommu api
On Fri, 28 Aug 2020 at 00:34, Tom Murphy <murphyt7 at tcd.ie> wrote:> > On Thu, 27 Aug 2020 at 22:36, Logan Gunthorpe <logang at deltatee.com> wrote: > > > > > > > > On 2020-08-23 6:04 p.m., Tom Murphy wrote: > > > I have added a check for the sg_dma_len == 0 : > > > """ > > > } __sgt_iter(struct scatterlist *sgl, bool dma) { > > > struct sgt_iter s = { .sgp = sgl }; > > > > > > + if (sgl && sg_dma_len(sgl) == 0) > > > + s.sgp = NULL; > > > > > > if (s.sgp) { > > > ..... > > > """ > > > at location [1]. > > > but it doens't fix the problem. > > > > Based on my read of the code, it looks like we also need to change usage > > of sgl->length... Something like the rough patch below, maybe? > > > > Also, Tom, do you have an updated version of the patchset to convert the > > Intel IOMMU to dma-iommu available? The last one I've found doesn't > > apply cleanly (I'm assuming parts of it have been merged in slightly > > modified forms). > > > > I'll try and post one in the next 24hoursI have just posted this now: The subject of the cover letter is: "[PATCH V2 0/5] Convert the intel iommu driver to the dma-iommu api"> > > Thanks, > > > > Logan > > > > -- > > > > diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h > > b/drivers/gpu/drm/i915/i915 > > index b7b59328cb76..9367ac801f0c 100644 > > --- a/drivers/gpu/drm/i915/i915_scatterlist.h > > +++ b/drivers/gpu/drm/i915/i915_scatterlist.h > > @@ -27,13 +27,19 @@ static __always_inline struct sgt_iter { > > } __sgt_iter(struct scatterlist *sgl, bool dma) { > > struct sgt_iter s = { .sgp = sgl }; > > > > + if (sgl && !sg_dma_len(s.sgp)) > > + s.sgp = NULL; > > + > > if (s.sgp) { > > s.max = s.curr = s.sgp->offset; > > - s.max += s.sgp->length; > > - if (dma) > > + > > + if (dma) { > > + s.max += sg_dma_len(s.sgp); > > s.dma = sg_dma_address(s.sgp); > > - else > > + } else { > > + s.max += s.sgp->length; > > s.pfn = page_to_pfn(sg_page(s.sgp)); > > + } > > } > > > > return s;