[PATCH 1/5 v2] dma-mapping: add generic dma_get_page_shift API

[Nishanth Aravamudan]

Drivers like NVMe need to be able to determine the page size used for
DMA transfers. Add a new API that defaults to return PAGE_SHIFT on all
architectures.

Signed-off-by: Nishanth Aravamudan <nacc at linux.vnet.ibm.com>

diff --git a/include/asm-generic/dma-mapping-common.h b/include/asm-generic/dma-mapping-common.h
index b1bc954..86e4e97 100644
--- a/include/asm-generic/dma-mapping-common.h
+++ b/include/asm-generic/dma-mapping-common.h
@@ -355,4 +355,11 @@ static inline int dma_set_mask(struct device *dev, u64 mask)
 }
 #endif
 
+#ifndef HAVE_ARCH_DMA_GET_PAGE_SHIFT
+static inline unsigned long dma_get_page_shift(struct device *dev)
+{
+	return PAGE_SHIFT;
+}
+#endif
+
 #endif