diff options
| author | Christoph Hellwig <hch@lst.de> | 2022-11-09 08:37:17 +0100 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2022-11-21 09:37:20 +0100 |
| commit | ffcb754584603adf7039d7972564fbf6febdc542 (patch) | |
| tree | ffcb4184b490a6559a16baea06020804da298c80 /arch/arm/mm | |
| parent | 3306877aff07363f9bede7f9edf2c4ea4f5b20be (diff) | |
dma-mapping: reject __GFP_COMP in dma_alloc_attrs
DMA allocations can never be turned back into a page pointer, so
requesting compound pages doesn't make sense and it can't even be
supported at all by various backends.
Reject __GFP_COMP with a warning in dma_alloc_attrs, and stop clearing
the flag in the arm dma ops and dma-iommu.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/dma-mapping.c | 17 |
1 files changed, 0 insertions, 17 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index d7909091cf97..c135f6e37a00 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -564,14 +564,6 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, if (mask < 0xffffffffULL) gfp |= GFP_DMA; - /* - * Following is a work-around (a.k.a. hack) to prevent pages - * with __GFP_COMP being passed to split_page() which cannot - * handle them. The real problem is that this flag probably - * should be 0 on ARM as it is not supported on this - * platform; see CONFIG_HUGETLBFS. - */ - gfp &= ~(__GFP_COMP); args.gfp = gfp; *handle = DMA_MAPPING_ERROR; @@ -1093,15 +1085,6 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, return __iommu_alloc_simple(dev, size, gfp, handle, coherent_flag, attrs); - /* - * Following is a work-around (a.k.a. hack) to prevent pages - * with __GFP_COMP being passed to split_page() which cannot - * handle them. The real problem is that this flag probably - * should be 0 on ARM as it is not supported on this - * platform; see CONFIG_HUGETLBFS. - */ - gfp &= ~(__GFP_COMP); - pages = __iommu_alloc_buffer(dev, size, gfp, attrs, coherent_flag); if (!pages) return NULL; |