[PATCH] crypto: marvell/cesa - Fix DMA API misuse

Robin Murphy robin.murphy at arm.com
Wed Jan 10 07:15:43 PST 2018


phys_to_dma() is an internal helper for certain DMA API implementations,
and is not appropriate for drivers to use. It appears that what the CESA
driver really wants to be using is dma_map_resource() - admittedly that
didn't exist when the offending code was first merged, but it does now.

Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---

Found by inspection and compile-tested only

 drivers/crypto/marvell/cesa.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/crypto/marvell/cesa.c b/drivers/crypto/marvell/cesa.c
index 293832488cc9..f81fa4a3e66b 100644
--- a/drivers/crypto/marvell/cesa.c
+++ b/drivers/crypto/marvell/cesa.c
@@ -15,6 +15,7 @@
  */
 
 #include <linux/delay.h>
+#include <linux/dma-mapping.h>
 #include <linux/genalloc.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
@@ -409,8 +410,11 @@ static int mv_cesa_get_sram(struct platform_device *pdev, int idx)
 	if (IS_ERR(engine->sram))
 		return PTR_ERR(engine->sram);
 
-	engine->sram_dma = phys_to_dma(cesa->dev,
-				       (phys_addr_t)res->start);
+	engine->sram_dma = dma_map_resource(cesa->dev, res->start,
+					    cesa->sram_size,
+					    DMA_BIDIRECTIONAL, 0);
+	if (dma_mapping_error(cesa->dev, engine->sram_dma))
+		return -ENOMEM;
 
 	return 0;
 }
@@ -420,11 +424,12 @@ static void mv_cesa_put_sram(struct platform_device *pdev, int idx)
 	struct mv_cesa_dev *cesa = platform_get_drvdata(pdev);
 	struct mv_cesa_engine *engine = &cesa->engines[idx];
 
-	if (!engine->pool)
-		return;
-
-	gen_pool_free(engine->pool, (unsigned long)engine->sram,
-		      cesa->sram_size);
+	if (engine->pool)
+		gen_pool_free(engine->pool, (unsigned long)engine->sram,
+			      cesa->sram_size);
+	else
+		dma_unmap_resource(cesa->dev, engine->sram_dma,
+				   cesa->sram_size, DMA_BIDIRECTIONAL, 0);
 }
 
 static int mv_cesa_probe(struct platform_device *pdev)
-- 
2.13.4.dirty




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