Re: [PATCH v1 22/36] dma-remap: drop nth_page() in dma_common_contiguous_remap()

Lorenzo Stoakes <[email protected]> Thu, 28 Aug 2025 18:29:12 +0100
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Message-ID <[email protected]> 
On Thu, Aug 28, 2025 at 12:01:26AM +0200, David Hildenbrand wrote:
> dma_common_contiguous_remap() is used to remap an "allocated contiguous
> region". Within a single allocation, there is no need to use nth_page()
> anymore.
>
> Neither the buddy, nor hugetlb, nor CMA will hand out problematic page
> ranges.
>
> Acked-by: Marek Szyprowski <[email protected]>
> Cc: Marek Szyprowski <[email protected]>
> Cc: Robin Murphy <[email protected]>
> Signed-off-by: David Hildenbrand <[email protected]>

Nice!

LGTM, so:

Reviewed-by: Lorenzo Stoakes <[email protected]>

> ---
>  kernel/dma/remap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
> index 9e2afad1c6152..b7c1c0c92d0c8 100644
> --- a/kernel/dma/remap.c
> +++ b/kernel/dma/remap.c
> @@ -49,7 +49,7 @@ void *dma_common_contiguous_remap(struct page *page, size_t size,
>  	if (!pages)
>  		return NULL;
>  	for (i = 0; i < count; i++)
> -		pages[i] = nth_page(page, i);
> +		pages[i] = page++;
>  	vaddr = vmap(pages, count, VM_DMA_COHERENT, prot);
>  	kvfree(pages);
>
> --
> 2.50.1
>