ARM: use flush_kernel_dcache_area() for dmabounce
After copying data from the bounce buffer to the real buffer, use flush_kernel_dcache_page() to ensure that data is written back in manner coherent with future userspace mappings. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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@ -308,15 +308,11 @@ static inline void unmap_single(struct device *dev, dma_addr_t dma_addr,
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memcpy(ptr, buf->safe, size);
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/*
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* DMA buffers must have the same cache properties
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* as if they were really used for DMA - which means
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* data must be written back to RAM. Note that
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* we don't use dmac_flush_range() here for the
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* bidirectional case because we know the cache
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* lines will be coherent with the data written.
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* Since we may have written to a page cache page,
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* we need to ensure that the data will be coherent
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* with user mappings.
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*/
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dmac_clean_range(ptr, ptr + size);
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outer_clean_range(__pa(ptr), __pa(ptr) + size);
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__cpuc_flush_kernel_dcache_area(ptr, size);
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}
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free_safe_buffer(dev->archdata.dmabounce, buf);
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}
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