Re: [PATCH 06/44] iommu/dma: don't rely on DMA_ERROR_CODE
From: Robin Murphy <hidden>
Date: 2017-06-08 13:59:21
Also in:
dri-devel, linux-arm-kernel, linux-iommu, linux-mips, linux-samsung-soc, linux-sh, linux-tegra, linuxppc-dev, lkml, sparclinux
Hi Christoph, On 08/06/17 14:25, Christoph Hellwig wrote:
DMA_ERROR_CODE is not a public API and will go away soon. dma dma-iommu driver already implements a proper ->mapping_error method, so it's only using the value internally. Add a new local define using the value that arm64 which is the only current user of dma-iommu.
It would be fine to just use 0, since dma-iommu already makes sure that that will never be allocated for a valid DMA address. Otherwise, looks good! Robin.
quoted hunk ↗ jump to hunk
Signed-off-by: Christoph Hellwig <redacted> --- drivers/iommu/dma-iommu.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 62618e77bedc..638aea814b94 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c@@ -31,6 +31,8 @@ #include <linux/scatterlist.h> #include <linux/vmalloc.h> +#define IOMMU_MAPPING_ERROR (~(dma_addr_t)0) + struct iommu_dma_msi_page { struct list_head list; dma_addr_t iova;@@ -500,7 +502,7 @@ void iommu_dma_free(struct device *dev, struct page **pages, size_t size, { __iommu_dma_unmap(iommu_get_domain_for_dev(dev), *handle, size); __iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT); - *handle = DMA_ERROR_CODE; + *handle = IOMMU_MAPPING_ERROR; } /**@@ -533,7 +535,7 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp, dma_addr_t iova; unsigned int count, min_size, alloc_sizes = domain->pgsize_bitmap; - *handle = DMA_ERROR_CODE; + *handle = IOMMU_MAPPING_ERROR; min_size = alloc_sizes & -alloc_sizes; if (min_size < PAGE_SIZE) {@@ -627,11 +629,11 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev); if (!iova) - return DMA_ERROR_CODE; + return IOMMU_MAPPING_ERROR; if (iommu_map(domain, iova, phys - iova_off, size, prot)) { iommu_dma_free_iova(cookie, iova, size); - return DMA_ERROR_CODE; + return IOMMU_MAPPING_ERROR; } return iova + iova_off; }@@ -671,7 +673,7 @@ static int __finalise_sg(struct device *dev, struct scatterlist *sg, int nents, s->offset += s_iova_off; s->length = s_length; - sg_dma_address(s) = DMA_ERROR_CODE; + sg_dma_address(s) = IOMMU_MAPPING_ERROR; sg_dma_len(s) = 0; /*@@ -714,11 +716,11 @@ static void __invalidate_sg(struct scatterlist *sg, int nents) int i; for_each_sg(sg, s, nents, i) { - if (sg_dma_address(s) != DMA_ERROR_CODE) + if (sg_dma_address(s) != IOMMU_MAPPING_ERROR) s->offset += sg_dma_address(s); if (sg_dma_len(s)) s->length = sg_dma_len(s); - sg_dma_address(s) = DMA_ERROR_CODE; + sg_dma_address(s) = IOMMU_MAPPING_ERROR; sg_dma_len(s) = 0; } }@@ -836,7 +838,7 @@ void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle, int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) { - return dma_addr == DMA_ERROR_CODE; + return dma_addr == IOMMU_MAPPING_ERROR; } static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev,