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Commit 0aeba2d0 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Michael Ellerman
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powerpc/dma: properly wire up the unmap_page and unmap_sg methods 



The unmap methods need to transfer memory ownership back from the
device to the cpu by identical means as dma_sync_*_to_cpu. I'm not
sure powerpc needs to do any work in this transfer direction, but
given that it does invalidate the caches in dma_sync_*_to_cpu already
we should make sure we also do so on unmapping.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
[mpe: s/dir/direction in dma_nommu_unmap_page()]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 92863569

arch/powerpc/kernel/dma.c

+8 −1
Original line number Diff line number Diff line
@@ -210,10 +210,15 @@ static int dma_nommu_map_sg(struct device *dev, struct scatterlist *sgl, 
	return nents;

}



static void dma_nommu_unmap_sg(struct device *dev, struct scatterlist *sg,

static void dma_nommu_unmap_sg(struct device *dev, struct scatterlist *sgl,

				int nents, enum dma_data_direction direction,

				unsigned long attrs)

{

	struct scatterlist *sg;

	int i;



	for_each_sg(sgl, sg, nents, i)

		__dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);

}



static u64 dma_nommu_get_required_mask(struct device *dev)
@@ -247,6 +252,8 @@ static inline void dma_nommu_unmap_page(struct device *dev, 
					 enum dma_data_direction direction,

					 unsigned long attrs)

{

	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))

		__dma_sync(bus_to_virt(dma_address), size, direction);

}



#ifdef CONFIG_NOT_COHERENT_CACHE