From a20f507f577b04f286c88a4885ac528e69f6f308 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 Feb 2019 08:01:04 +0100 Subject: [PATCH] powerpc/dma: untangle vio_dma_mapping_ops from dma_iommu_ops vio_dma_mapping_ops currently does a lot of indirect calls through dma_iommu_ops, which not only make the code harder to follow but are also expensive in the post-spectre world. Unwind the indirect calls by calling the ppc_iommu_* or iommu_* APIs directly applicable, or just use the dma_iommu_* methods directly where we can. Signed-off-by: Christoph Hellwig Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/iommu.h | 1 + arch/powerpc/kernel/dma-iommu.c | 2 +- arch/powerpc/platforms/pseries/vio.c | 87 ++++++++++++---------------- 3 files changed, 38 insertions(+), 52 deletions(-) diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h index 17524d222a7b..bd069a6542ab 100644 --- a/arch/powerpc/include/asm/iommu.h +++ b/arch/powerpc/include/asm/iommu.h @@ -237,6 +237,7 @@ static inline void iommu_del_device(struct device *dev) } #endif /* !CONFIG_IOMMU_API */ +u64 dma_iommu_get_required_mask(struct device *dev); #else static inline void *get_iommu_table_base(struct device *dev) diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c index 9c9bcaae2f75..dd8601cd20df 100644 --- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c @@ -92,7 +92,7 @@ int dma_iommu_dma_supported(struct device *dev, u64 mask) return 1; } -static u64 dma_iommu_get_required_mask(struct device *dev) +u64 dma_iommu_get_required_mask(struct device *dev) { struct iommu_table *tbl = get_iommu_table_base(dev); u64 mask; diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c index 1fad4649735b..7870bf99168c 100644 --- a/arch/powerpc/platforms/pseries/vio.c +++ b/arch/powerpc/platforms/pseries/vio.c @@ -492,7 +492,9 @@ static void *vio_dma_iommu_alloc_coherent(struct device *dev, size_t size, return NULL; } - ret = dma_iommu_ops.alloc(dev, size, dma_handle, flag, attrs); + ret = iommu_alloc_coherent(dev, get_iommu_table_base(dev), size, + dma_handle, dev->coherent_dma_mask, flag, + dev_to_node(dev)); if (unlikely(ret == NULL)) { vio_cmo_dealloc(viodev, roundup(size, PAGE_SIZE)); atomic_inc(&viodev->cmo.allocs_failed); @@ -507,8 +509,7 @@ static void vio_dma_iommu_free_coherent(struct device *dev, size_t size, { struct vio_dev *viodev = to_vio_dev(dev); - dma_iommu_ops.free(dev, size, vaddr, dma_handle, attrs); - + iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, dma_handle); vio_cmo_dealloc(viodev, roundup(size, PAGE_SIZE)); } @@ -518,22 +519,22 @@ static dma_addr_t vio_dma_iommu_map_page(struct device *dev, struct page *page, unsigned long attrs) { struct vio_dev *viodev = to_vio_dev(dev); - struct iommu_table *tbl; + struct iommu_table *tbl = get_iommu_table_base(dev); dma_addr_t ret = DMA_MAPPING_ERROR; - tbl = get_iommu_table_base(dev); - if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl)))) { - atomic_inc(&viodev->cmo.allocs_failed); - return ret; - } - - ret = dma_iommu_ops.map_page(dev, page, offset, size, direction, attrs); - if (unlikely(dma_mapping_error(dev, ret))) { - vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl))); - atomic_inc(&viodev->cmo.allocs_failed); - } - + if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl)))) + goto out_fail; + ret = iommu_map_page(dev, tbl, page, offset, size, device_to_mask(dev), + direction, attrs); + if (unlikely(ret == DMA_MAPPING_ERROR)) + goto out_deallocate; return ret; + +out_deallocate: + vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl))); +out_fail: + atomic_inc(&viodev->cmo.allocs_failed); + return DMA_MAPPING_ERROR; } static void vio_dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, @@ -542,11 +543,9 @@ static void vio_dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, unsigned long attrs) { struct vio_dev *viodev = to_vio_dev(dev); - struct iommu_table *tbl; - - tbl = get_iommu_table_base(dev); - dma_iommu_ops.unmap_page(dev, dma_handle, size, direction, attrs); + struct iommu_table *tbl = get_iommu_table_base(dev); + iommu_unmap_page(tbl, dma_handle, size, direction, attrs); vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl))); } @@ -555,34 +554,32 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, unsigned long attrs) { struct vio_dev *viodev = to_vio_dev(dev); - struct iommu_table *tbl; + struct iommu_table *tbl = get_iommu_table_base(dev); struct scatterlist *sgl; int ret, count; size_t alloc_size = 0; - tbl = get_iommu_table_base(dev); for_each_sg(sglist, sgl, nelems, count) alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE(tbl)); - if (vio_cmo_alloc(viodev, alloc_size)) { - atomic_inc(&viodev->cmo.allocs_failed); - return 0; - } - - ret = dma_iommu_ops.map_sg(dev, sglist, nelems, direction, attrs); - - if (unlikely(!ret)) { - vio_cmo_dealloc(viodev, alloc_size); - atomic_inc(&viodev->cmo.allocs_failed); - return ret; - } + if (vio_cmo_alloc(viodev, alloc_size)) + goto out_fail; + ret = ppc_iommu_map_sg(dev, tbl, sglist, nelems, device_to_mask(dev), + direction, attrs); + if (unlikely(!ret)) + goto out_deallocate; 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); - return ret; + +out_deallocate: + vio_cmo_dealloc(viodev, alloc_size); +out_fail: + atomic_inc(&viodev->cmo.allocs_failed); + return 0; } static void vio_dma_iommu_unmap_sg(struct device *dev, @@ -591,30 +588,18 @@ static void vio_dma_iommu_unmap_sg(struct device *dev, unsigned long attrs) { struct vio_dev *viodev = to_vio_dev(dev); - struct iommu_table *tbl; + struct iommu_table *tbl = get_iommu_table_base(dev); struct scatterlist *sgl; size_t alloc_size = 0; int count; - tbl = get_iommu_table_base(dev); 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); - + ppc_iommu_unmap_sg(tbl, sglist, nelems, direction, attrs); vio_cmo_dealloc(viodev, alloc_size); } -static int vio_dma_iommu_dma_supported(struct device *dev, u64 mask) -{ - return dma_iommu_ops.dma_supported(dev, mask); -} - -static u64 vio_dma_get_required_mask(struct device *dev) -{ - return dma_iommu_ops.get_required_mask(dev); -} - static const struct dma_map_ops vio_dma_mapping_ops = { .alloc = vio_dma_iommu_alloc_coherent, .free = vio_dma_iommu_free_coherent, @@ -623,8 +608,8 @@ static const struct dma_map_ops vio_dma_mapping_ops = { .unmap_sg = vio_dma_iommu_unmap_sg, .map_page = vio_dma_iommu_map_page, .unmap_page = vio_dma_iommu_unmap_page, - .dma_supported = vio_dma_iommu_dma_supported, - .get_required_mask = vio_dma_get_required_mask, + .dma_supported = dma_iommu_dma_supported, + .get_required_mask = dma_iommu_get_required_mask, }; /** -- 2.30.2