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| author | Christoph Hellwig <hch@lst.de> | 2019-06-03 13:48:57 +0300 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2019-06-25 09:12:42 +0300 |
| commit | 34ab03160eda51839be6dd5a939680963266707c (patch) | |
| tree | 3c6810a7c739a86ea785d2707a2a6b5dedf754c9 /arch/arm/mm/dma-mapping-nommu.c | |
| parent | ab746573c4055ae1fa226715502fb9bb9be29a79 (diff) | |
| download | linux-34ab03160eda51839be6dd5a939680963266707c.tar.xz | |
arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support
The arm-nommu DMA code supports DMA_ATTR_NON_CONSISTENT allocations, but
does not provide a cache_sync operation. This means any user of it
will never be able to actually transfer cache ownership and thus cause
coherency bugs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Diffstat (limited to 'arch/arm/mm/dma-mapping-nommu.c')
| -rw-r--r-- | arch/arm/mm/dma-mapping-nommu.c | 24 |
1 files changed, 3 insertions, 21 deletions
diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c index f304b10e23a4..bc003df45546 100644 --- a/arch/arm/mm/dma-mapping-nommu.c +++ b/arch/arm/mm/dma-mapping-nommu.c @@ -39,18 +39,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size, unsigned long attrs) { - void *ret; - - /* - * Try generic allocator first if we are advertised that - * consistency is not required. - */ - - if (attrs & DMA_ATTR_NON_CONSISTENT) - return dma_direct_alloc_pages(dev, size, dma_handle, gfp, - attrs); - - ret = dma_alloc_from_global_coherent(size, dma_handle); + void *ret = dma_alloc_from_global_coherent(size, dma_handle); /* * dma_alloc_from_global_coherent() may fail because: @@ -70,16 +59,9 @@ static void arm_nommu_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - if (attrs & DMA_ATTR_NON_CONSISTENT) { - dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs); - } else { - int ret = dma_release_from_global_coherent(get_order(size), - cpu_addr); - - WARN_ON_ONCE(ret == 0); - } + int ret = dma_release_from_global_coherent(get_order(size), cpu_addr); - return; + WARN_ON_ONCE(ret == 0); } static int arm_nommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, |