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ARM: use flush_kernel_dcache_area() for dmabounce

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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>
This commit is contained in:
Russell King 2009-11-26 12:31:15 +00:00
parent 2c9b9c8490
commit f74f7e57ae
1 changed files with 4 additions and 8 deletions
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12
arch/arm/common/dmabounce.c
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@ -308,15 +308,11 @@ static inline void unmap_single(struct device *dev, dma_addr_t dma_addr,
memcpy(ptr, buf->safe, size);
/*
* DMA buffers must have the same cache properties
* as if they were really used for DMA - which means
* data must be written back to RAM. Note that
* we don't use dmac_flush_range() here for the
* bidirectional case because we know the cache
* lines will be coherent with the data written.
* Since we may have written to a page cache page,
* we need to ensure that the data will be coherent
* with user mappings.
*/
dmac_clean_range(ptr, ptr + size);
outer_clean_range(__pa(ptr), __pa(ptr) + size);
__cpuc_flush_kernel_dcache_area(ptr, size);
}
free_safe_buffer(dev->archdata.dmabounce, buf);
}