Subject: [PATCH] arm64: Align CMA sizes to PAGE_SIZE

From: [email-masked] (Catalin Marinas)
Date: Tue, 4 Feb 2014 18:00:03 +0000

On Sat, Feb 01, 2014 at 12:23:54AM +0000, Laura Abbott wrote:
> dma_alloc_from_contiguous takes number of pages for a size.
> Align up the dma size passed in to page size to avoid truncation
> and allocation failures on sizes less than PAGE_SIZE.
> 
> Cc: Will Deacon <[email-masked]>
> Cc: Catalin Marinas <[email-masked]>
> Signed-off-by: Laura Abbott <[email-masked]>
> ---
>  arch/arm64/mm/dma-mapping.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
> index 864b256..be2696e 100644
> --- a/arch/arm64/mm/dma-mapping.c
> +++ b/arch/arm64/mm/dma-mapping.c
> @@ -44,6 +44,8 @@ static void *arm64_swiotlb_alloc_coherent(struct device *dev, size_t size,
>  		flags |= GFP_DMA32;
>  	if (IS_ENABLED(CONFIG_CMA)) {
>  		unsigned long pfn;
> +
> +		size = PAGE_ALIGN(size);
>  		pfn = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
>  							get_order(size));

The patch looks ok, but it doesn't apply. In my kernel (3.14-rc1),
dma_alloc_from_contiguous returns a struct page.

Thanks.

-- 
Catalin