From 21b95aaf5f2212764d37b7569f3829a295e4042c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 20 May 2019 09:29:34 +0200 Subject: iommu/dma: Refactor the page array remapping allocator Move the call to dma_common_pages_remap into __iommu_dma_alloc and rename it to iommu_dma_alloc_remap. This creates a self-contained helper for remapped pages allocation and mapping. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy Signed-off-by: Joerg Roedel --- drivers/iommu/dma-iommu.c | 54 +++++++++++++++++++++++------------------------ 1 file changed, 26 insertions(+), 28 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 5e81165e6755..0ffb7805de77 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -564,9 +564,9 @@ static struct page **__iommu_dma_get_pages(void *cpu_addr) } /** - * iommu_dma_free - Free a buffer allocated by __iommu_dma_alloc() + * iommu_dma_free - Free a buffer allocated by iommu_dma_alloc_remap() * @dev: Device which owns this buffer - * @pages: Array of buffer pages as returned by __iommu_dma_alloc() + * @pages: Array of buffer pages as returned by __iommu_dma_alloc_remap() * @size: Size of buffer in bytes * @handle: DMA address of buffer * @@ -582,33 +582,35 @@ static void __iommu_dma_free(struct device *dev, struct page **pages, } /** - * __iommu_dma_alloc - Allocate and map a buffer contiguous in IOVA space + * iommu_dma_alloc_remap - Allocate and map a buffer contiguous in IOVA space * @dev: Device to allocate memory for. Must be a real device * attached to an iommu_dma_domain * @size: Size of buffer in bytes + * @dma_handle: Out argument for allocated DMA handle * @gfp: Allocation flags * @attrs: DMA attributes for this allocation - * @prot: IOMMU mapping flags - * @handle: Out argument for allocated DMA handle * * If @size is less than PAGE_SIZE, then a full CPU page will be allocated, * but an IOMMU which supports smaller pages might not map the whole thing. * - * Return: Array of struct page pointers describing the buffer, - * or NULL on failure. + * Return: Mapped virtual address, or NULL on failure. */ -static struct page **__iommu_dma_alloc(struct device *dev, size_t size, - gfp_t gfp, unsigned long attrs, int prot, dma_addr_t *handle) +static void *iommu_dma_alloc_remap(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; + bool coherent = dev_is_dma_coherent(dev); + int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); + pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); + unsigned int count, min_size, alloc_sizes = domain->pgsize_bitmap; struct page **pages; struct sg_table sgt; dma_addr_t iova; - unsigned int count, min_size, alloc_sizes = domain->pgsize_bitmap; + void *vaddr; - *handle = DMA_MAPPING_ERROR; + *dma_handle = DMA_MAPPING_ERROR; min_size = alloc_sizes & -alloc_sizes; if (min_size < PAGE_SIZE) { @@ -634,7 +636,7 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, if (sg_alloc_table_from_pages(&sgt, pages, count, 0, size, GFP_KERNEL)) goto out_free_iova; - if (!(prot & IOMMU_CACHE)) { + if (!(ioprot & IOMMU_CACHE)) { struct scatterlist *sg; int i; @@ -642,14 +644,21 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, arch_dma_prep_coherent(sg_page(sg), sg->length); } - if (iommu_map_sg(domain, iova, sgt.sgl, sgt.orig_nents, prot) + if (iommu_map_sg(domain, iova, sgt.sgl, sgt.orig_nents, ioprot) < size) goto out_free_sg; - *handle = iova; + vaddr = dma_common_pages_remap(pages, size, VM_USERMAP, prot, + __builtin_return_address(0)); + if (!vaddr) + goto out_unmap; + + *dma_handle = iova; sg_free_table(&sgt); - return pages; + return vaddr; +out_unmap: + __iommu_dma_unmap(dev, iova, size); out_free_sg: sg_free_table(&sgt); out_free_iova: @@ -1008,18 +1017,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, size >> PAGE_SHIFT); } } else { - pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); - struct page **pages; - - pages = __iommu_dma_alloc(dev, iosize, gfp, attrs, ioprot, - handle); - if (!pages) - return NULL; - - addr = dma_common_pages_remap(pages, size, VM_USERMAP, prot, - __builtin_return_address(0)); - if (!addr) - __iommu_dma_free(dev, pages, iosize, handle); + addr = iommu_dma_alloc_remap(dev, iosize, handle, gfp, attrs); } return addr; } @@ -1033,7 +1031,7 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, /* * @cpu_addr will be one of 4 things depending on how it was allocated: * - A remapped array of pages for contiguous allocations. - * - A remapped array of pages from __iommu_dma_alloc(), for all + * - A remapped array of pages from iommu_dma_alloc_remap(), for all * non-atomic allocations. * - A non-cacheable alias from the atomic pool, for atomic * allocations by non-coherent devices. -- cgit v1.2.3-55-g7522