From: Victoria Milhoan Date: Wed, 5 Aug 2015 18:28:41 +0000 (-0700) Subject: crypto: caam - Use local sg pointers to walk the scatterlist X-Git-Tag: v4.14-rc1~4492^2~72 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ec0273039b6606ae08132f41854381e0d7371ded;p=platform%2Fkernel%2Flinux-rpi.git crypto: caam - Use local sg pointers to walk the scatterlist Avoid moving the head of the scatterlist entry by using temporary pointers to walk the scatterlist. Signed-off-by: Victoria Milhoan Tested-by: Horia Geantă Signed-off-by: Herbert Xu --- diff --git a/drivers/crypto/caam/sg_sw_sec4.h b/drivers/crypto/caam/sg_sw_sec4.h index 711bb39..18cd6d1 100644 --- a/drivers/crypto/caam/sg_sw_sec4.h +++ b/drivers/crypto/caam/sg_sw_sec4.h @@ -105,9 +105,15 @@ static inline void dma_unmap_sg_chained( { if (unlikely(chained)) { int i; + struct scatterlist *tsg = sg; + + /* + * Use a local copy of the sg pointer to avoid moving the + * head of the list pointed to by sg as we walk the list. + */ for (i = 0; i < nents; i++) { - dma_unmap_sg(dev, sg, 1, dir); - sg = sg_next(sg); + dma_unmap_sg(dev, tsg, 1, dir); + tsg = sg_next(tsg); } } else if (nents) { dma_unmap_sg(dev, sg, nents, dir); @@ -118,19 +124,23 @@ 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; + struct scatterlist *tsg = sg; + + /* + * Use a local copy of the sg pointer to avoid moving the + * head of the list pointed to by sg as we walk the list. + */ for (i = 0; i < nents; i++) { - if (!dma_map_sg(dev, sg, 1, dir)) { - dma_unmap_sg_chained(dev, first, i, dir, + if (!dma_map_sg(dev, tsg, 1, dir)) { + dma_unmap_sg_chained(dev, sg, i, dir, chained); nents = 0; break; } - sg = sg_next(sg); + tsg = sg_next(tsg); } } else nents = dma_map_sg(dev, sg, nents, dir);