dma-mapping: move the dma_coherent flag to struct device

Various architectures support both coherent and non-coherent dma on a
per-device basis.  Move the dma_noncoherent flag from the mips archdata
field to struct device proper to prepare the infrastructure for reuse on
other architectures.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/dma-noncoherent.h b/include/linux/dma-noncoherent.h
index a0aa00c..ce97325 100644
--- a/include/linux/dma-noncoherent.h
+++ b/include/linux/dma-noncoherent.h
@@ -4,6 +4,22 @@
 
 #include <linux/dma-mapping.h>
 
+#ifdef CONFIG_ARCH_HAS_DMA_COHERENCE_H
+#include <asm/dma-coherence.h>
+#elif defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
+	defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+	defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
+static inline bool dev_is_dma_coherent(struct device *dev)
+{
+	return dev->dma_coherent;
+}
+#else
+static inline bool dev_is_dma_coherent(struct device *dev)
+{
+	return true;
+}
+#endif /* CONFIG_ARCH_HAS_DMA_COHERENCE_H */
+
 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 		gfp_t gfp, unsigned long attrs);
 void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,