Commit 2e86a047 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

dma-direct: use phys_to_dma 



This means it uses whatever linear remapping scheme that the architecture
provides is used in the generic dma_direct ops.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarVladimir Murzin <vladimir.murzin@arm.com>
parent 002e6745

lib/dma-direct.c

+7 −11
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 *	lib/dma-noop.c

 *

 * DMA operations that map to physical addresses without flushing memory.

 * DMA operations that map physical memory directly without using an IOMMU or

 * flushing caches.

 */

#include <linux/export.h>

#include <linux/mm.h>

#include <linux/dma-mapping.h>

#include <linux/dma-direct.h>

#include <linux/scatterlist.h>

#include <linux/pfn.h>
@@ -17,7 +16,7 @@ static void *dma_direct_alloc(struct device *dev, size_t size, 


	ret = (void *)__get_free_pages(gfp, get_order(size));

	if (ret)

		*dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);

		*dma_handle = phys_to_dma(dev, virt_to_phys(ret));



	return ret;

}
@@ -32,7 +31,7 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, 
		unsigned long offset, size_t size, enum dma_data_direction dir,

		unsigned long attrs)

{

	return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);

	return phys_to_dma(dev, page_to_phys(page)) + offset;

}



static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
@@ -42,12 +41,9 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, 
	struct scatterlist *sg;



	for_each_sg(sgl, sg, nents, i) {

		dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);

		void *va;



		BUG_ON(!sg_page(sg));

		va = sg_virt(sg);

		sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;



		sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg));

		sg_dma_len(sg) = sg->length;

	}