Adding Robin.
On Fri, Jul 02, 2021 at 02:37:41PM +0900, David Stevens wrote: > From: David Stevens <[email protected]> > > Make map_swiotlb and unmap_swiotlb only for mapping, and consistently > use sync_single_for and sync_sg_for functions for swiotlb sync and arch > sync. This ensures that the same code path is responsible for syncing > regardless of whether or not SKIP_CPU_SYNC is set. In the process, fix > various places where the original physical address and swiotlb tlb_addr > are mixed up: > - Make sync_sg functions call sync_single functions for untrusted > devices, so they use tlb_addr when checking is_swiotlb_buffer and > when doing arch sync if necessary. > - Use tlb_addr for arch sync in map_page if necessary. > - In map_sg, map before syncing so that arch sync can target the > bounce buffer if necessary. > - Pass SKIP_CPU_SYNC to swiotlb map and unmap to avoid double syncing > the swiotlb. This had previously only happened in the unmap_page > case, but is now necessary for all swiotlb cases. > > Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers") > Signed-off-by: David Stevens <[email protected]> > --- > drivers/iommu/dma-iommu.c | 82 ++++++++++++++++++++++++--------------- > 1 file changed, 51 insertions(+), 31 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 7bcdd1205535..24d1042cd052 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -505,7 +505,8 @@ static void __iommu_dma_unmap_swiotlb(struct device *dev, > dma_addr_t dma_addr, > __iommu_dma_unmap(dev, dma_addr, size); > > if (unlikely(is_swiotlb_buffer(phys))) > - swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); > + swiotlb_tbl_unmap_single(dev, phys, size, dir, > + attrs | DMA_ATTR_SKIP_CPU_SYNC); > } > > static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, > @@ -536,7 +537,8 @@ static dma_addr_t __iommu_dma_map(struct device *dev, > phys_addr_t phys, > > static dma_addr_t __iommu_dma_map_swiotlb(struct device *dev, phys_addr_t > phys, > size_t org_size, dma_addr_t dma_mask, bool coherent, > - enum dma_data_direction dir, unsigned long attrs) > + enum dma_data_direction dir, unsigned long attrs, > + phys_addr_t *adj_phys) > { > int prot = dma_info_to_prot(dir, coherent, attrs); > struct iommu_domain *domain = iommu_get_dma_domain(dev); > @@ -555,7 +557,8 @@ static dma_addr_t __iommu_dma_map_swiotlb(struct device > *dev, phys_addr_t phys, > iova_offset(iovad, phys | org_size)) { > aligned_size = iova_align(iovad, org_size); > phys = swiotlb_tbl_map_single(dev, phys, org_size, > - aligned_size, dir, attrs); > + aligned_size, dir, > + attrs | DMA_ATTR_SKIP_CPU_SYNC); > > if (phys == DMA_MAPPING_ERROR) > return DMA_MAPPING_ERROR; > @@ -573,6 +576,8 @@ static dma_addr_t __iommu_dma_map_swiotlb(struct device > *dev, phys_addr_t phys, > > memset(padding_start, 0, padding_size); > } > + if (adj_phys) > + *adj_phys = phys; > > iova = __iommu_dma_map(dev, phys, aligned_size, prot, dma_mask); > if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(phys)) > @@ -785,15 +790,17 @@ static void iommu_dma_sync_single_for_cpu(struct device > *dev, > swiotlb_sync_single_for_cpu(dev, phys, size, dir); > } > > -static void iommu_dma_sync_single_for_device(struct device *dev, > - dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) > +static void __iommu_dma_sync_single_for_device(struct device *dev, > + dma_addr_t dma_handle, size_t size, > + enum dma_data_direction dir, phys_addr_t phys) > { > - phys_addr_t phys; > - > if (dev_is_dma_coherent(dev) && !dev_is_untrusted(dev)) > return; > > - phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle); > + if (phys == 0) > + phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), > + dma_handle); > + > if (is_swiotlb_buffer(phys)) > swiotlb_sync_single_for_device(dev, phys, size, dir); > > @@ -801,6 +808,12 @@ static void iommu_dma_sync_single_for_device(struct > device *dev, > arch_sync_dma_for_device(phys, size, dir); > } > > +static void iommu_dma_sync_single_for_device(struct device *dev, > + dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) > +{ > + __iommu_dma_sync_single_for_device(dev, dma_handle, size, dir, 0); > +} > + > static void iommu_dma_sync_sg_for_cpu(struct device *dev, > struct scatterlist *sgl, int nelems, > enum dma_data_direction dir) > @@ -811,14 +824,13 @@ static void iommu_dma_sync_sg_for_cpu(struct device > *dev, > if (dev_is_dma_coherent(dev) && !dev_is_untrusted(dev)) > return; > > - for_each_sg(sgl, sg, nelems, i) { > - if (!dev_is_dma_coherent(dev)) > + if (dev_is_untrusted(dev)) > + for_each_sg(sgl, sg, nelems, i) > + iommu_dma_sync_single_for_cpu(dev, sg_dma_address(sg), > + sg->length, dir); > + else > + for_each_sg(sgl, sg, nelems, i) > arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir); > - > - if (is_swiotlb_buffer(sg_phys(sg))) > - swiotlb_sync_single_for_cpu(dev, sg_phys(sg), > - sg->length, dir); > - } > } > > static void iommu_dma_sync_sg_for_device(struct device *dev, > @@ -831,29 +843,30 @@ static void iommu_dma_sync_sg_for_device(struct device > *dev, > if (dev_is_dma_coherent(dev) && !dev_is_untrusted(dev)) > return; > > - for_each_sg(sgl, sg, nelems, i) { > - if (is_swiotlb_buffer(sg_phys(sg))) > - swiotlb_sync_single_for_device(dev, sg_phys(sg), > - sg->length, dir); > - > - if (!dev_is_dma_coherent(dev)) > + if (dev_is_untrusted(dev)) > + for_each_sg(sgl, sg, nelems, i) > + __iommu_dma_sync_single_for_device(dev, > + sg_dma_address(sg), > + sg->length, dir, 0); > + else > + for_each_sg(sgl, sg, nelems, i) > arch_sync_dma_for_device(sg_phys(sg), sg->length, dir); > - } > } > > static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, > unsigned long offset, size_t size, enum dma_data_direction dir, > unsigned long attrs) > { > - phys_addr_t phys = page_to_phys(page) + offset; > + phys_addr_t phys = page_to_phys(page) + offset, adj_phys; > bool coherent = dev_is_dma_coherent(dev); > dma_addr_t dma_handle; > > - dma_handle = __iommu_dma_map_swiotlb(dev, phys, size, dma_get_mask(dev), > - coherent, dir, attrs); > - if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && > + dma_handle = __iommu_dma_map_swiotlb(dev, phys, size, > + dma_get_mask(dev), coherent, dir, attrs, &adj_phys); > + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && > dma_handle != DMA_MAPPING_ERROR) > - arch_sync_dma_for_device(phys, size, dir); > + __iommu_dma_sync_single_for_device(dev, dma_handle, size, > + dir, adj_phys); > return dma_handle; > } > > @@ -960,7 +973,7 @@ static int iommu_dma_map_sg_swiotlb(struct device *dev, > struct scatterlist *sg, > for_each_sg(sg, s, nents, i) { > sg_dma_address(s) = __iommu_dma_map_swiotlb(dev, sg_phys(s), > s->length, dma_get_mask(dev), > - dev_is_dma_coherent(dev), dir, attrs); > + dev_is_dma_coherent(dev), dir, attrs, NULL); > if (sg_dma_address(s) == DMA_MAPPING_ERROR) > goto out_unmap; > sg_dma_len(s) = s->length; > @@ -991,17 +1004,24 @@ static int iommu_dma_map_sg(struct device *dev, struct > scatterlist *sg, > dma_addr_t iova; > size_t iova_len = 0; > unsigned long mask = dma_get_seg_boundary(dev); > - int i; > + int i, early_mapped = 0; > > if (static_branch_unlikely(&iommu_deferred_attach_enabled) && > iommu_deferred_attach(dev, domain)) > return 0; > > + if (dev_is_untrusted(dev)) { > + early_mapped = iommu_dma_map_sg_swiotlb(dev, sg, nents, > + dir, attrs); > + if (!early_mapped) > + return 0; > + } > + > if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) > iommu_dma_sync_sg_for_device(dev, sg, nents, dir); > > - if (dev_is_untrusted(dev)) > - return iommu_dma_map_sg_swiotlb(dev, sg, nents, dir, attrs); > + if (early_mapped) > + return early_mapped; > > /* > * Work out how much IOVA space we need, and align the segments to > -- > 2.32.0.93.g670b81a890-goog _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
