iommu_sg_num_pages() is a helper that walks a scattlerlist and counts pages taking segment boundaries and iommu_num_pages() into account. Up-level it for determining the IOVA range that dma_map_ops established at dma_map_sg() time. The intent is to iommu_unmap() the IOVA range in advance of freeing IOVA range. Cc: Joerg Roedel <joro@xxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/iommu/amd_iommu.c | 30 ++---------------------------- drivers/iommu/iommu.c | 27 +++++++++++++++++++++++++++ include/linux/iommu.h | 2 ++ 3 files changed, 31 insertions(+), 28 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index c8e1a45af182..4795b0823469 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2459,32 +2459,6 @@ static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size, __unmap_single(dma_dom, dma_addr, size, dir); } -static int sg_num_pages(struct device *dev, - struct scatterlist *sglist, - int nelems) -{ - unsigned long mask, boundary_size; - struct scatterlist *s; - int i, npages = 0; - - mask = dma_get_seg_boundary(dev); - boundary_size = mask + 1 ? ALIGN(mask + 1, PAGE_SIZE) >> PAGE_SHIFT : - 1UL << (BITS_PER_LONG - PAGE_SHIFT); - - for_each_sg(sglist, s, nelems, i) { - int p, n; - - s->dma_address = npages << PAGE_SHIFT; - p = npages % boundary_size; - n = iommu_num_pages(sg_phys(s), s->length, PAGE_SIZE); - if (p + n > boundary_size) - npages += boundary_size - p; - npages += n; - } - - return npages; -} - /* * The exported map_sg function for dma_ops (handles scatter-gather * lists). @@ -2507,7 +2481,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist, dma_dom = to_dma_ops_domain(domain); dma_mask = *dev->dma_mask; - npages = sg_num_pages(dev, sglist, nelems); + npages = iommu_sg_num_pages(dev, sglist, nelems); address = dma_ops_alloc_iova(dev, dma_dom, npages, dma_mask); if (address == AMD_IOMMU_MAPPING_ERROR) @@ -2585,7 +2559,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist, startaddr = sg_dma_address(sglist) & PAGE_MASK; dma_dom = to_dma_ops_domain(domain); - npages = sg_num_pages(dev, sglist, nelems); + npages = iommu_sg_num_pages(dev, sglist, nelems); __unmap_single(dma_dom, startaddr, npages << PAGE_SHIFT, dir); } diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3de5c0bcb5cc..cfe6eeea3578 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -33,6 +33,7 @@ #include <linux/bitops.h> #include <linux/property.h> #include <trace/events/iommu.h> +#include <linux/iommu-helper.h> static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); @@ -1631,6 +1632,32 @@ size_t iommu_unmap_fast(struct iommu_domain *domain, } EXPORT_SYMBOL_GPL(iommu_unmap_fast); +int iommu_sg_num_pages(struct device *dev, struct scatterlist *sglist, + int nelems) +{ + unsigned long mask, boundary_size; + struct scatterlist *s; + int i, npages = 0; + + mask = dma_get_seg_boundary(dev); + boundary_size = mask + 1 ? ALIGN(mask + 1, PAGE_SIZE) >> PAGE_SHIFT + : 1UL << (BITS_PER_LONG - PAGE_SHIFT); + + for_each_sg(sglist, s, nelems, i) { + int p, n; + + s->dma_address = npages << PAGE_SHIFT; + p = npages % boundary_size; + n = iommu_num_pages(sg_phys(s), s->length, PAGE_SIZE); + if (p + n > boundary_size) + npages += boundary_size - p; + npages += n; + } + + return npages; +} +EXPORT_SYMBOL_GPL(iommu_sg_num_pages); + size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova, struct scatterlist *sg, unsigned int nents, int prot) { diff --git a/include/linux/iommu.h b/include/linux/iommu.h index a7f2ac689d29..5b2d20e1475a 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -303,6 +303,8 @@ extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size); extern size_t iommu_unmap_fast(struct iommu_domain *domain, unsigned long iova, size_t size); +extern int iommu_sg_num_pages(struct device *dev, struct scatterlist *sglist, + int nelems); extern size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova, struct scatterlist *sg,unsigned int nents, int prot); -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html