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

From: Niklas SÃderlund
Date: Sun May 08 2016 - 07:10:25 EST


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 SÃderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
---
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