From 38f7ea5a082bbde9e64b7ece389f20e71a9806f4 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Wed, 4 Jun 2014 16:06:56 -0700 Subject: [PATCH] arch/x86/kernel/pci-dma.c: fix dma_generic_alloc_coherent() when CONFIG_DMA_CMA is enabled dma_generic_alloc_coherent() firstly attempts to allocate by dma_alloc_from_contiguous() if CONFIG_DMA_CMA is enabled. But the memory region allocated by it may not fit within the device's DMA mask. This change makes it fall back to usual alloc_pages_node() allocation for such cases. Signed-off-by: Akinobu Mita Cc: Marek Szyprowski Cc: Konrad Rzeszutek Wilk Cc: David Woodhouse Cc: Don Dutile Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/kernel/pci-dma.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index e5f4e9629e61..a25e202bb319 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -101,8 +101,13 @@ void *dma_generic_alloc_coherent(struct device *dev, size_t size, again: page = NULL; /* CMA can be used only in the context which permits sleeping */ - if (flag & __GFP_WAIT) + if (flag & __GFP_WAIT) { page = dma_alloc_from_contiguous(dev, count, get_order(size)); + if (page && page_to_phys(page) + size > dma_mask) { + dma_release_from_contiguous(dev, page, count); + page = NULL; + } + } /* fallback */ if (!page) page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));