From 0c3b3171ceccb8830c2bb5adff1b4e9b204c1450 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 4 Nov 2018 20:29:28 +0100 Subject: dma-mapping: move the arm64 noncoherent alloc/free support to common code The arm64 codebase to implement coherent dma allocation for architectures with non-coherent DMA is a good start for a generic implementation, given that is uses the generic remap helpers, provides the atomic pool for allocations that can't sleep and still is realtively simple and well tested. Move it to kernel/dma and allow architectures to opt into it using a config symbol. Architectures just need to provide a new arch_dma_prep_coherent helper to writeback an invalidate the caches for any memory that gets remapped for uncached access. Signed-off-by: Christoph Hellwig Reviewed-by: Will Deacon Reviewed-by: Robin Murphy --- include/linux/dma-noncoherent.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/dma-noncoherent.h') diff --git a/include/linux/dma-noncoherent.h b/include/linux/dma-noncoherent.h index 9051b055beec..306557331d7d 100644 --- a/include/linux/dma-noncoherent.h +++ b/include/linux/dma-noncoherent.h @@ -69,4 +69,6 @@ static inline void arch_sync_dma_for_cpu_all(struct device *dev) } #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */ +void arch_dma_prep_coherent(struct page *page, size_t size); + #endif /* _LINUX_DMA_NONCOHERENT_H */ -- cgit v1.2.3-59-g8ed1b