Commit fd509249 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

ARM/dma-mapping: remove get_coherent_dma_mask 



The core DMA code already checks for valid DMA masks earlier on, and
doesn't allow NULL struct device pointers.  Remove the now not required
checks.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent a4a4d11a

arch/arm/mm/dma-mapping.c

+4 −37
Original line number Diff line number Diff line
@@ -219,7 +219,7 @@ const struct dma_map_ops arm_coherent_dma_ops = { 
};

EXPORT_SYMBOL(arm_coherent_dma_ops);



static int __dma_supported(struct device *dev, u64 mask, bool warn)

static int __dma_supported(struct device *dev, u64 mask)

{

	unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit);
@@ -227,41 +227,11 @@ static int __dma_supported(struct device *dev, u64 mask, bool warn) 
	 * Translate the device's DMA mask to a PFN limit.  This

	 * PFN number includes the page which we can DMA to.

	 */

	if (dma_to_pfn(dev, mask) < max_dma_pfn) {

		if (warn)

			dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",

				 mask,

				 dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,

				 max_dma_pfn + 1);

	if (dma_to_pfn(dev, mask) < max_dma_pfn)

		return 0;

	}



	return 1;

}



static u64 get_coherent_dma_mask(struct device *dev)

{

	u64 mask = (u64)DMA_BIT_MASK(32);



	if (dev) {

		mask = dev->coherent_dma_mask;



		/*

		 * Sanity check the DMA mask - it must be non-zero, and

		 * must be able to be satisfied by a DMA allocation.

		 */

		if (mask == 0) {

			dev_warn(dev, "coherent DMA mask is unset\n");

			return 0;

		}



		if (!__dma_supported(dev, mask, true))

			return 0;

	}



	return mask;

}



static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag)

{

	/*
@@ -688,7 +658,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, 
			 gfp_t gfp, pgprot_t prot, bool is_coherent,

			 unsigned long attrs, const void *caller)

{

	u64 mask = get_coherent_dma_mask(dev);

	u64 mask = dev->coherent_dma_mask;

	struct page *page = NULL;

	void *addr;

	bool allowblock, cma;
@@ -712,9 +682,6 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, 
	}

#endif



	if (!mask)

		return NULL;



	buf = kzalloc(sizeof(*buf),

		      gfp & ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM));

	if (!buf)
@@ -1095,7 +1062,7 @@ void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, 
 */

int arm_dma_supported(struct device *dev, u64 mask)

{

	return __dma_supported(dev, mask, false);

	return __dma_supported(dev, mask);

}



static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent)