Commit f532959b authored by Fenghua Yu's avatar Fenghua Yu Committed by David Woodhouse
Browse files

intel-iommu: Correct sglist size calculation. 



In domain_sg_mapping(), use aligned_nrpages() instead of hand-coded
rounding code for calculating the size of each sg elem. This means that
on IA64 we correctly round up to the MM page size, not just to the VT-d
page size.

Also remove the incorrect mm_to_dma_pfn() when intel_map_sg() calls
domain_sg_mapping() -- the 'size' variable is in VT-d pages already.

Signed-off-by: default avatarFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent 90bc1a65

drivers/pci/intel-iommu.c

+10 −10
Original line number Diff line number Diff line
@@ -1648,6 +1648,14 @@ static int domain_context_mapped(struct pci_dev *pdev) 
					     tmp->devfn);

}



/* Returns a number of VTD pages, but aligned to MM page size */

static inline unsigned long aligned_nrpages(unsigned long host_addr,

					    size_t size)

{

	host_addr &= ~PAGE_MASK;

	return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT;

}



static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,

			    struct scatterlist *sg, unsigned long phys_pfn,

			    unsigned long nr_pages, int prot)
@@ -1675,7 +1683,7 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn, 
		uint64_t tmp;



		if (!sg_res) {

			sg_res = (sg->offset + sg->length + VTD_PAGE_SIZE - 1) >> VTD_PAGE_SHIFT;

			sg_res = aligned_nrpages(sg->offset, sg->length);

			sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;

			sg->dma_length = sg->length;

			pteval = page_to_phys(sg_page(sg)) | prot;
@@ -2415,14 +2423,6 @@ error: 
	return ret;

}



/* Returns a number of VTD pages, but aligned to MM page size */

static inline unsigned long aligned_nrpages(unsigned long host_addr,

					    size_t size)

{

	host_addr &= ~PAGE_MASK;

	return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT;

}



/* This takes a number of _MM_ pages, not VTD pages */

static struct iova *intel_alloc_iova(struct device *dev,

				     struct dmar_domain *domain,
@@ -2875,7 +2875,7 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int ne 


	start_vpfn = mm_to_dma_pfn(iova->pfn_lo);



	ret = domain_sg_mapping(domain, start_vpfn, sglist, mm_to_dma_pfn(size), prot);

	ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);

	if (unlikely(ret)) {

		/*  clear the page */

		dma_pte_clear_range(domain, start_vpfn,

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