Messages in this thread | | | Subject | Re: [PATCH 20/24] iommu/dma: Refactor iommu_dma_mmap | From | Robin Murphy <> | Date | Wed, 22 May 2019 18:11:09 +0100 |
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On 20/05/2019 08:29, Christoph Hellwig wrote: > Inline __iommu_dma_mmap_pfn into the main function, and use the > fact that __iommu_dma_get_pages return NULL for remapped contigous > allocations to simplify the code flow a bit.
This would be a good point to get rid of __iommu_dma_mmap() now too.
Robin.
> Signed-off-by: Christoph Hellwig <hch@lst.de> > Reviewed-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/iommu/dma-iommu.c | 46 ++++++++++----------------------------- > 1 file changed, 11 insertions(+), 35 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index fa95794868a4..84150ca7b572 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -1042,31 +1042,12 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, > return cpu_addr; > } > > -static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, > - unsigned long pfn, size_t size) > -{ > - int ret = -ENXIO; > - unsigned long nr_vma_pages = vma_pages(vma); > - unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; > - unsigned long off = vma->vm_pgoff; > - > - if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) { > - ret = remap_pfn_range(vma, vma->vm_start, > - pfn + off, > - vma->vm_end - vma->vm_start, > - vma->vm_page_prot); > - } > - > - return ret; > -} > - > static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, > void *cpu_addr, dma_addr_t dma_addr, size_t size, > unsigned long attrs) > { > unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; > - unsigned long off = vma->vm_pgoff; > - struct page **pages; > + unsigned long pfn, off = vma->vm_pgoff; > int ret; > > vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs); > @@ -1077,24 +1058,19 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, > if (off >= nr_pages || vma_pages(vma) > nr_pages - off) > return -ENXIO; > > - if (!is_vmalloc_addr(cpu_addr)) { > - unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); > - return __iommu_dma_mmap_pfn(vma, pfn, size); > - } > + if (is_vmalloc_addr(cpu_addr)) { > + struct page **pages = __iommu_dma_get_pages(cpu_addr); > > - if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) { > - /* > - * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped, > - * hence in the vmalloc space. > - */ > - unsigned long pfn = vmalloc_to_pfn(cpu_addr); > - return __iommu_dma_mmap_pfn(vma, pfn, size); > + if (pages) > + return __iommu_dma_mmap(pages, size, vma); > + pfn = vmalloc_to_pfn(cpu_addr); > + } else { > + pfn = page_to_pfn(virt_to_page(cpu_addr)); > } > > - pages = __iommu_dma_get_pages(cpu_addr); > - if (!pages) > - return -ENXIO; > - return __iommu_dma_mmap(pages, size, vma); > + return remap_pfn_range(vma, vma->vm_start, pfn + off, > + vma->vm_end - vma->vm_start, > + vma->vm_page_prot); > } > > static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt, >
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