Re: [PATCH v4 05/44] arm64: dma-mapping: Use unsigned long for dma_attrs

From: Robin Murphy <robin.murphy@arm.com>
To: Krzysztof Kozlowski <k.kozlowski@samsung.com>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Jisheng Zhang <jszhang@marvell.com>,
	Joerg Roedel <jroedel@suse.de>, Arnd Bergmann <arnd@arndb.de>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	linux-kernel@vger.kernel.org, hch@infradead.org, "Suthikulpanit,
	Suravee" <Suravee.Suthikulpanit@amd.com>,
	linux-arm-kernel@lists.infradead.org,
	Marek Szyprowski <m.szyprowski@samsung.com>
Subject: Re: [PATCH v4 05/44] arm64: dma-mapping: Use unsigned long for dma_attrs
Date: Fri, 10 Jun 2016 11:51:48 +0100	[thread overview]
Message-ID: <575A9BC4.3090603@arm.com> (raw)
In-Reply-To: <1465553521-27303-6-git-send-email-k.kozlowski@samsung.com>

Hi Krzysztof,

On 10/06/16 11:11, Krzysztof Kozlowski wrote:
> Split out subsystem specific changes for easier reviews. This will be
> squashed with main commit.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> ---
>   arch/arm64/mm/dma-mapping.c | 57 +++++++++++++++++++++++----------------------
>   1 file changed, 29 insertions(+), 28 deletions(-)
>
> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
> index 0ef620a34c4e..a7686028dfeb 100644
> --- a/arch/arm64/mm/dma-mapping.c
> +++ b/arch/arm64/mm/dma-mapping.c
> @@ -29,7 +29,7 @@
>
>   #include <asm/cacheflush.h>
>
> -static pgprot_t __get_dma_pgprot(const struct dma_attrs *attrs, pgprot_t prot,
> +static pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot,
>   				 bool coherent)

Is this series intended to replace the patches currently in -next adding 
that "const"? (I was momentarily puzzled why this wouldn't apply locally)

>   {
>   	if (!coherent || dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
> @@ -88,7 +88,7 @@ static int __free_from_pool(void *start, size_t size)
>
>   static void *__dma_alloc_coherent(struct device *dev, size_t size,
>   				  dma_addr_t *dma_handle, gfp_t flags,
> -				  const struct dma_attrs *attrs)
> +				  unsigned long attrs)
>   {
>   	if (dev == NULL) {
>   		WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
> @@ -118,7 +118,7 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size,
>
>   static void __dma_free_coherent(struct device *dev, size_t size,
>   				void *vaddr, dma_addr_t dma_handle,
> -				const struct dma_attrs *attrs)
> +				unsigned long attrs)
>   {
>   	bool freed;
>   	phys_addr_t paddr = dma_to_phys(dev, dma_handle);
> @@ -137,7 +137,7 @@ static void __dma_free_coherent(struct device *dev, size_t size,
>
>   static void *__dma_alloc(struct device *dev, size_t size,
>   			 dma_addr_t *dma_handle, gfp_t flags,
> -			 struct dma_attrs *attrs)
> +			 unsigned long attrs)
>   {
>   	struct page *page;
>   	void *ptr, *coherent_ptr;
> @@ -185,7 +185,7 @@ no_mem:
>
>   static void __dma_free(struct device *dev, size_t size,
>   		       void *vaddr, dma_addr_t dma_handle,
> -		       struct dma_attrs *attrs)
> +		       unsigned long attrs)
>   {
>   	void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle));
>
> @@ -202,7 +202,7 @@ static void __dma_free(struct device *dev, size_t size,
>   static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
>   				     unsigned long offset, size_t size,
>   				     enum dma_data_direction dir,
> -				     struct dma_attrs *attrs)
> +				     unsigned long attrs)
>   {
>   	dma_addr_t dev_addr;
>
> @@ -216,7 +216,7 @@ static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
>
>   static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
>   				 size_t size, enum dma_data_direction dir,
> -				 struct dma_attrs *attrs)
> +				 unsigned long attrs)
>   {
>   	if (!is_device_dma_coherent(dev))
>   		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
> @@ -225,7 +225,7 @@ static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
>
>   static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
>   				  int nelems, enum dma_data_direction dir,
> -				  struct dma_attrs *attrs)
> +				  unsigned long attrs)
>   {
>   	struct scatterlist *sg;
>   	int i, ret;
> @@ -242,7 +242,7 @@ static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
>   static void __swiotlb_unmap_sg_attrs(struct device *dev,
>   				     struct scatterlist *sgl, int nelems,
>   				     enum dma_data_direction dir,
> -				     struct dma_attrs *attrs)
> +				     unsigned long attrs)
>   {
>   	struct scatterlist *sg;
>   	int i;
> @@ -303,7 +303,7 @@ static void __swiotlb_sync_sg_for_device(struct device *dev,
>   static int __swiotlb_mmap(struct device *dev,
>   			  struct vm_area_struct *vma,
>   			  void *cpu_addr, dma_addr_t dma_addr, size_t size,
> -			  struct dma_attrs *attrs)
> +			  unsigned long attrs)
>   {
>   	int ret = -ENXIO;
>   	unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >>
> @@ -330,7 +330,7 @@ static int __swiotlb_mmap(struct device *dev,
>
>   static int __swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
>   				 void *cpu_addr, dma_addr_t handle, size_t size,
> -				 struct dma_attrs *attrs)
> +				 unsigned long attrs)
>   {
>   	int ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
>
> @@ -425,21 +425,21 @@ out:
>
>   static void *__dummy_alloc(struct device *dev, size_t size,
>   			   dma_addr_t *dma_handle, gfp_t flags,
> -			   struct dma_attrs *attrs)
> +			   unsigned long attrs)
>   {
>   	return NULL;
>   }
>
>   static void __dummy_free(struct device *dev, size_t size,
>   			 void *vaddr, dma_addr_t dma_handle,
> -			 struct dma_attrs *attrs)
> +			 unsigned long attrs)
>   {
>   }
>
>   static int __dummy_mmap(struct device *dev,
>   			struct vm_area_struct *vma,
>   			void *cpu_addr, dma_addr_t dma_addr, size_t size,
> -			struct dma_attrs *attrs)
> +			unsigned long attrs)
>   {
>   	return -ENXIO;
>   }
> @@ -447,20 +447,20 @@ static int __dummy_mmap(struct device *dev,
>   static dma_addr_t __dummy_map_page(struct device *dev, struct page *page,
>   				   unsigned long offset, size_t size,
>   				   enum dma_data_direction dir,
> -				   struct dma_attrs *attrs)
> +				   unsigned long attrs)
>   {
>   	return DMA_ERROR_CODE;
>   }
>
>   static void __dummy_unmap_page(struct device *dev, dma_addr_t dev_addr,
>   			       size_t size, enum dma_data_direction dir,
> -			       struct dma_attrs *attrs)
> +			       unsigned long attrs)
>   {
>   }
>
>   static int __dummy_map_sg(struct device *dev, struct scatterlist *sgl,
>   			  int nelems, enum dma_data_direction dir,
> -			  struct dma_attrs *attrs)
> +			  unsigned long attrs)
>   {
>   	return 0;
>   }
> @@ -468,7 +468,7 @@ static int __dummy_map_sg(struct device *dev, struct scatterlist *sgl,
>   static void __dummy_unmap_sg(struct device *dev,
>   			     struct scatterlist *sgl, int nelems,
>   			     enum dma_data_direction dir,
> -			     struct dma_attrs *attrs)
> +			     unsigned long attrs)
>   {
>   }
>
> @@ -540,7 +540,7 @@ static void flush_page(struct device *dev, const void *virt, phys_addr_t phys)
>
>   static void *__iommu_alloc_attrs(struct device *dev, size_t size,
>   				 dma_addr_t *handle, gfp_t gfp,
> -				 struct dma_attrs *attrs)
> +				 unsigned long attrs)
>   {
>   	bool coherent = is_device_dma_coherent(dev);
>   	int ioprot = dma_direction_to_prot(DMA_BIDIRECTIONAL, coherent);
> @@ -600,7 +600,8 @@ static void *__iommu_alloc_attrs(struct device *dev, size_t size,
>   }
>
>   static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
> -			       dma_addr_t handle, struct dma_attrs *attrs)
> +			       dma_addr_t handle,
> +			       unsigned long attrs)

Nit: unnecessary line break?

Otherwise, though, I'm all for the idea;

Acked-by: Robin Murphy <robin.murphy@arm.com>

>   {
>   	size_t iosize = size;
>
> @@ -616,7 +617,7 @@ static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
>   	 * Hence how dodgy the below logic looks...
>   	 */
>   	if (__in_atomic_pool(cpu_addr, size)) {
> -		iommu_dma_unmap_page(dev, handle, iosize, 0, NULL);
> +		iommu_dma_unmap_page(dev, handle, iosize, 0, 0);
>   		__free_from_pool(cpu_addr, size);
>   	} else if (is_vmalloc_addr(cpu_addr)){
>   		struct vm_struct *area = find_vm_area(cpu_addr);
> @@ -626,14 +627,14 @@ static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
>   		iommu_dma_free(dev, area->pages, iosize, &handle);
>   		dma_common_free_remap(cpu_addr, size, VM_USERMAP);
>   	} else {
> -		iommu_dma_unmap_page(dev, handle, iosize, 0, NULL);
> +		iommu_dma_unmap_page(dev, handle, iosize, 0, 0);
>   		__free_pages(virt_to_page(cpu_addr), get_order(size));
>   	}
>   }
>
>   static int __iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
>   			      void *cpu_addr, dma_addr_t dma_addr, size_t size,
> -			      struct dma_attrs *attrs)
> +			      unsigned long attrs)
>   {
>   	struct vm_struct *area;
>   	int ret;
> @@ -653,7 +654,7 @@ static int __iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
>
>   static int __iommu_get_sgtable(struct device *dev, struct sg_table *sgt,
>   			       void *cpu_addr, dma_addr_t dma_addr,
> -			       size_t size, struct dma_attrs *attrs)
> +			       size_t size, unsigned long attrs)
>   {
>   	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
>   	struct vm_struct *area = find_vm_area(cpu_addr);
> @@ -694,7 +695,7 @@ static void __iommu_sync_single_for_device(struct device *dev,
>   static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
>   				   unsigned long offset, size_t size,
>   				   enum dma_data_direction dir,
> -				   struct dma_attrs *attrs)
> +				   unsigned long attrs)
>   {
>   	bool coherent = is_device_dma_coherent(dev);
>   	int prot = dma_direction_to_prot(dir, coherent);
> @@ -709,7 +710,7 @@ static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
>
>   static void __iommu_unmap_page(struct device *dev, dma_addr_t dev_addr,
>   			       size_t size, enum dma_data_direction dir,
> -			       struct dma_attrs *attrs)
> +			       unsigned long attrs)
>   {
>   	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
>   		__iommu_sync_single_for_cpu(dev, dev_addr, size, dir);
> @@ -747,7 +748,7 @@ static void __iommu_sync_sg_for_device(struct device *dev,
>
>   static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
>   				int nelems, enum dma_data_direction dir,
> -				struct dma_attrs *attrs)
> +				unsigned long attrs)
>   {
>   	bool coherent = is_device_dma_coherent(dev);
>
> @@ -761,7 +762,7 @@ static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
>   static void __iommu_unmap_sg_attrs(struct device *dev,
>   				   struct scatterlist *sgl, int nelems,
>   				   enum dma_data_direction dir,
> -				   struct dma_attrs *attrs)
> +				   unsigned long attrs)
>   {
>   	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
>   		__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);
>