From c4e0e892ab0579d4de3ca6d260d537fc16b39790 Mon Sep 17 00:00:00 2001 From: Martin Oliveira Date: Thu, 29 Jul 2021 14:15:28 -0600 Subject: [PATCH] powerpc/iommu: return error code from .map_sg() ops The .map_sg() op now expects an error code instead of zero on failure. Propagate the error up if vio_dma_iommu_map_sg() fails. ppc_iommu_map_sg() may fail either because of iommu_range_alloc() or because of tbl->it_ops->set(). The former only supports returning an error with DMA_MAPPING_ERROR and an examination of the latter indicates that it may return arch-specific errors (for example, tce_buildmulti_pSeriesLP()). Hence, coalesce all of those errors into -EIO, per the documentation on dma_map_sgtable(). Signed-off-by: Martin Oliveira Signed-off-by: Logan Gunthorpe Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Geoff Levand Signed-off-by: Christoph Hellwig --- arch/powerpc/kernel/iommu.c | 4 ++-- arch/powerpc/platforms/ps3/system-bus.c | 2 +- arch/powerpc/platforms/pseries/vio.c | 5 +++-- 3 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 2af89a5..a8ec4fe 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -473,7 +473,7 @@ int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl, BUG_ON(direction == DMA_NONE); if ((nelems == 0) || !tbl) - return 0; + return -EINVAL; outs = s = segstart = &sglist[0]; outcount = 1; @@ -599,7 +599,7 @@ int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl, if (s == outs) break; } - return 0; + return -EIO; } diff --git a/arch/powerpc/platforms/ps3/system-bus.c b/arch/powerpc/platforms/ps3/system-bus.c index 1a56658..c54eb46 100644 --- a/arch/powerpc/platforms/ps3/system-bus.c +++ b/arch/powerpc/platforms/ps3/system-bus.c @@ -663,7 +663,7 @@ static int ps3_ioc0_map_sg(struct device *_dev, struct scatterlist *sg, unsigned long attrs) { BUG(); - return 0; + return -EINVAL; } static void ps3_sb_unmap_sg(struct device *_dev, struct scatterlist *sg, diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c index e00f372..e31e59c 100644 --- a/arch/powerpc/platforms/pseries/vio.c +++ b/arch/powerpc/platforms/pseries/vio.c @@ -560,7 +560,8 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, for_each_sg(sglist, sgl, nelems, count) alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE(tbl)); - if (vio_cmo_alloc(viodev, alloc_size)) + ret = vio_cmo_alloc(viodev, alloc_size); + if (ret) goto out_fail; ret = ppc_iommu_map_sg(dev, tbl, sglist, nelems, dma_get_mask(dev), direction, attrs); @@ -577,7 +578,7 @@ out_deallocate: vio_cmo_dealloc(viodev, alloc_size); out_fail: atomic_inc(&viodev->cmo.allocs_failed); - return 0; + return ret; } static void vio_dma_iommu_unmap_sg(struct device *dev, -- 2.7.4