From: Akinobu Mita Date: Wed, 24 Jun 2015 23:54:43 +0000 (-0700) Subject: powerpc: use for_each_sg() X-Git-Tag: firefly_0821_release~176^2~1578^2~89 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5935877af47653d737d2401f9b6200f1fb4a03eb;p=firefly-linux-kernel-4.4.55.git powerpc: use for_each_sg() This replaces the plain loop over the sglist array with for_each_sg() macro which consists of sg_next() function calls. Since powerpc does select ARCH_HAS_SG_CHAIN, it is necessary to use for_each_sg() in order to loop over each sg element. This also help find problems with drivers that do not properly initialize their sg tables when CONFIG_DEBUG_SG is enabled. Signed-off-by: Akinobu Mita Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c index b41426c60ef6..5f8dcdaa2820 100644 --- a/arch/powerpc/kernel/vio.c +++ b/arch/powerpc/kernel/vio.c @@ -557,11 +557,11 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, struct vio_dev *viodev = to_vio_dev(dev); struct iommu_table *tbl; struct scatterlist *sgl; - int ret, count = 0; + int ret, count; size_t alloc_size = 0; tbl = get_iommu_table_base(dev); - for (sgl = sglist; count < nelems; count++, sgl++) + for_each_sg(sglist, sgl, nelems, count) alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE(tbl)); if (vio_cmo_alloc(viodev, alloc_size)) { @@ -577,7 +577,7 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, return ret; } - for (sgl = sglist, count = 0; count < ret; count++, sgl++) + for_each_sg(sglist, sgl, ret, count) alloc_size -= roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl)); if (alloc_size) vio_cmo_dealloc(viodev, alloc_size); @@ -594,10 +594,10 @@ static void vio_dma_iommu_unmap_sg(struct device *dev, struct iommu_table *tbl; struct scatterlist *sgl; size_t alloc_size = 0; - int count = 0; + int count; tbl = get_iommu_table_base(dev); - for (sgl = sglist; count < nelems; count++, sgl++) + for_each_sg(sglist, sgl, nelems, count) alloc_size += roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl)); dma_iommu_ops.unmap_sg(dev, sglist, nelems, direction, attrs);