[PATCH 1/2] dma-mapping: add __dma_sync_single_for_device()

Niklas Söderlund niklas.soderlund+renesas at ragnatech.se
Sun May 8 03:59:55 PDT 2016


Some users of the DMA mapping API calls dma_sync_single_for_device()
from the dma_map_single() call path. This will cause false warning
printouts if CONFIG_DMA_API_DEBUG are enabled.

The reason for the warning are that debug_dma_sync_single_for_device()
will be called before debug_dma_map_page() so the new mapping can't be
found and are believed to be invalid. Add __dma_sync_single_for_device()
that don't call into debug_dma_sync_single_for_device() and can be used
in these situations.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas at ragnatech.se>
---
 include/linux/dma-mapping.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 9ea9aba..0e4d3a6 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -224,7 +224,7 @@ static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
 	debug_dma_sync_single_for_cpu(dev, addr, size, dir);
 }
 
-static inline void dma_sync_single_for_device(struct device *dev,
+static inline void __dma_sync_single_for_device(struct device *dev,
 					      dma_addr_t addr, size_t size,
 					      enum dma_data_direction dir)
 {
@@ -233,6 +233,13 @@ static inline void dma_sync_single_for_device(struct device *dev,
 	BUG_ON(!valid_dma_direction(dir));
 	if (ops->sync_single_for_device)
 		ops->sync_single_for_device(dev, addr, size, dir);
+}
+
+static inline void dma_sync_single_for_device(struct device *dev,
+					      dma_addr_t addr, size_t size,
+					      enum dma_data_direction dir)
+{
+	__dma_sync_single_for_device(dev, addr, size, dir);
 	debug_dma_sync_single_for_device(dev, addr, size, dir);
 }
 
-- 
2.8.2




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