From 6c94711cbdf595766bc3295e437c3579943cd846 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 16 Jun 2015 13:54:22 +0800 Subject: [PATCH] crypto: caam - Handle errors in dma_map_sg_chained Currently dma_map_sg_chained does not handle errors from the underlying dma_map_sg calls. This patch adds rollback in case of an error by simply calling dma_unmap_sg_chained for the ones that we've already mapped. All current callers ignore the return value so this should have no impact on them. Signed-off-by: Herbert Xu --- drivers/crypto/caam/sg_sw_sec4.h | 47 ++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 20 deletions(-) diff --git a/drivers/crypto/caam/sg_sw_sec4.h b/drivers/crypto/caam/sg_sw_sec4.h index efbc1db8da53..b68b74cc7b77 100644 --- a/drivers/crypto/caam/sg_sw_sec4.h +++ b/drivers/crypto/caam/sg_sw_sec4.h @@ -100,25 +100,9 @@ static inline int sg_count(struct scatterlist *sg_list, int nbytes, return sg_nents; } -static int dma_map_sg_chained(struct device *dev, struct scatterlist *sg, - unsigned int nents, enum dma_data_direction dir, - bool chained) -{ - if (unlikely(chained)) { - int i; - for (i = 0; i < nents; i++) { - dma_map_sg(dev, sg, 1, dir); - sg = sg_next(sg); - } - } else { - dma_map_sg(dev, sg, nents, dir); - } - return nents; -} - -static int dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg, - unsigned int nents, enum dma_data_direction dir, - bool chained) +static inline void dma_unmap_sg_chained( + struct device *dev, struct scatterlist *sg, unsigned int nents, + enum dma_data_direction dir, bool chained) { if (unlikely(chained)) { int i; @@ -126,8 +110,31 @@ static int dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg, dma_unmap_sg(dev, sg, 1, dir); sg = sg_next(sg); } - } else { + } else if (nents) { dma_unmap_sg(dev, sg, nents, dir); } +} + +static inline int dma_map_sg_chained( + struct device *dev, struct scatterlist *sg, unsigned int nents, + enum dma_data_direction dir, bool chained) +{ + struct scatterlist *first = sg; + + if (unlikely(chained)) { + int i; + for (i = 0; i < nents; i++) { + if (!dma_map_sg(dev, sg, 1, dir)) { + dma_unmap_sg_chained(dev, first, i, dir, + chained); + nents = 0; + break; + } + + sg = sg_next(sg); + } + } else + nents = dma_map_sg(dev, sg, nents, dir); + return nents; }