From: David Hildenbrand <david@redhat.com>
Date: Mon, 1 Sep 2025 15:03:44 +0000 (+0200)
Subject: dma-remap: drop nth_page() in dma_common_contiguous_remap()
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a16c46c2402026162111ed9fd1fc28d25223443e;p=thirdparty%2Fkernel%2Fstable.git

dma-remap: drop nth_page() in dma_common_contiguous_remap()

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.

Link: https://lkml.kernel.org/r/20250901150359.867252-24-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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);