From: Robin Murphy <[email protected]> Apart from the iommu_dma_alloc_remap() case which remains sufficiently different that it's better off being self-contained, the rest of the logic can now be consolidated into a single flow which separates the logcially-distinct steps of allocating pages, getting the CPU address, and finally getting the IOMMU address.
Signed-off-by: Robin Murphy <[email protected]> [hch: split the page allocation into a new helper to simplify the flow] Signed-off-by: Christoph Hellwig <[email protected]> --- drivers/iommu/dma-iommu.c | 65 +++++++++++++++++++++------------------ 1 file changed, 35 insertions(+), 30 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 9b269f0792f3..acdfe866cb29 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -955,35 +955,14 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, __iommu_dma_free(dev, size, cpu_addr); } -static void *iommu_dma_alloc(struct device *dev, size_t size, - dma_addr_t *handle, gfp_t gfp, unsigned long attrs) +static void *iommu_dma_alloc_pages(struct device *dev, size_t size, + struct page **pagep, gfp_t gfp, unsigned long attrs) { bool coherent = dev_is_dma_coherent(dev); - int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); size_t alloc_size = PAGE_ALIGN(size); struct page *page = NULL; void *cpu_addr; - gfp |= __GFP_ZERO; - - if (gfpflags_allow_blocking(gfp) && - !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) - return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); - - if (!gfpflags_allow_blocking(gfp) && !coherent) { - cpu_addr = dma_alloc_from_pool(alloc_size, &page, gfp); - if (!cpu_addr) - return NULL; - - *handle = __iommu_dma_map(dev, page_to_phys(page), size, - ioprot); - if (*handle == DMA_MAPPING_ERROR) { - dma_free_from_pool(cpu_addr, alloc_size); - return NULL; - } - return cpu_addr; - } - if (gfpflags_allow_blocking(gfp)) page = dma_alloc_from_contiguous(dev, alloc_size >> PAGE_SHIFT, get_order(alloc_size), @@ -993,33 +972,59 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, if (!page) return NULL; - *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); - if (*handle == DMA_MAPPING_ERROR) - goto out_free_pages; - if (!coherent || PageHighMem(page)) { pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); cpu_addr = dma_common_contiguous_remap(page, alloc_size, VM_USERMAP, prot, __builtin_return_address(0)); if (!cpu_addr) - goto out_unmap; + goto out_free_pages; if (!coherent) arch_dma_prep_coherent(page, size); } else { cpu_addr = page_address(page); } + + *pagep = page; memset(cpu_addr, 0, alloc_size); return cpu_addr; -out_unmap: - __iommu_dma_unmap(dev, *handle, size); out_free_pages: if (!dma_release_from_contiguous(dev, page, alloc_size >> PAGE_SHIFT)) __free_pages(page, get_order(alloc_size)); return NULL; } +static void *iommu_dma_alloc(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp, unsigned long attrs) +{ + bool coherent = dev_is_dma_coherent(dev); + int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); + struct page *page = NULL; + void *cpu_addr; + + gfp |= __GFP_ZERO; + + if (gfpflags_allow_blocking(gfp) && + !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) + return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); + + if (!gfpflags_allow_blocking(gfp) && !coherent) + cpu_addr = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp); + else + cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs); + if (!cpu_addr) + return NULL; + + *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); + if (*handle == DMA_MAPPING_ERROR) { + __iommu_dma_free(dev, size, cpu_addr); + return NULL; + } + + return cpu_addr; +} + static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, unsigned long pfn, size_t size) { -- 2.20.1 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
