| Message ID | 8-v2-545d29711869+a76b5-iommu_pages_jgg@nvidia.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | iommu: Further abstract iommu-pages | expand |
On 2/15/25 01:07, Jason Gunthorpe wrote: > If all the inlines are unwound virt_to_dma_pfn() is simply: > return page_to_pfn(virt_to_page(p)) << (PAGE_SHIFT - VTD_PAGE_SHIFT); > > Which can be re-arranged to: > (page_to_pfn(virt_to_page(p)) << PAGE_SHIFT) >> VTD_PAGE_SHIFT > > The only caller is: > ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) > > re-arranged to: > ((page_to_pfn(virt_to_page(tmp_page)) << PAGE_SHIFT) >> VTD_PAGE_SHIFT) << VTD_PAGE_SHIFT > > Which simplifies to: > page_to_pfn(virt_to_page(tmp_page)) << PAGE_SHIFT > > That is the same as virt_to_phys(tmp_page), so just remove all of this. > > Signed-off-by: Jason Gunthorpe<jgg@nvidia.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 1e73bfa00329ae..d864eb180642f2 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -737,7 +737,8 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain, return NULL; domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE); - pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE; + pteval = virt_to_phys(tmp_page) | DMA_PTE_READ | + DMA_PTE_WRITE; if (domain->use_first_level) pteval |= DMA_FL_PTE_US | DMA_FL_PTE_ACCESS; diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index 6ea7bbe26b19d5..dd980808998da9 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -953,25 +953,6 @@ static inline unsigned long lvl_to_nr_pages(unsigned int lvl) return 1UL << min_t(int, (lvl - 1) * LEVEL_STRIDE, MAX_AGAW_PFN_WIDTH); } -/* VT-d pages must always be _smaller_ than MM pages. Otherwise things - are never going to work. */ -static inline unsigned long mm_to_dma_pfn_start(unsigned long mm_pfn) -{ - return mm_pfn << (PAGE_SHIFT - VTD_PAGE_SHIFT); -} -static inline unsigned long mm_to_dma_pfn_end(unsigned long mm_pfn) -{ - return ((mm_pfn + 1) << (PAGE_SHIFT - VTD_PAGE_SHIFT)) - 1; -} -static inline unsigned long page_to_dma_pfn(struct page *pg) -{ - return mm_to_dma_pfn_start(page_to_pfn(pg)); -} -static inline unsigned long virt_to_dma_pfn(void *p) -{ - return page_to_dma_pfn(virt_to_page(p)); -} - static inline void context_set_present(struct context_entry *context) { context->lo |= 1;
If all the inlines are unwound virt_to_dma_pfn() is simply: return page_to_pfn(virt_to_page(p)) << (PAGE_SHIFT - VTD_PAGE_SHIFT); Which can be re-arranged to: (page_to_pfn(virt_to_page(p)) << PAGE_SHIFT) >> VTD_PAGE_SHIFT The only caller is: ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) re-arranged to: ((page_to_pfn(virt_to_page(tmp_page)) << PAGE_SHIFT) >> VTD_PAGE_SHIFT) << VTD_PAGE_SHIFT Which simplifies to: page_to_pfn(virt_to_page(tmp_page)) << PAGE_SHIFT That is the same as virt_to_phys(tmp_page), so just remove all of this. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/iommu/intel/iommu.c | 3 ++- drivers/iommu/intel/iommu.h | 19 ------------------- 2 files changed, 2 insertions(+), 20 deletions(-)