Commit 9f683dfe authored by Petr Tesarik's avatar Petr Tesarik Committed by Marek Szyprowski
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dma-direct: clean up the logic in __dma_direct_alloc_pages() 



Convert a goto-based loop to a while() loop. To allow the simplification,
return early when allocation from CMA is successful. As a bonus, this early
return avoids a repeated dma_coherent_ok() check.

No functional change.

Signed-off-by: default avatarPetr Tesarik <ptesarik@suse.com>
Signed-off-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250710083829.1853466-1-ptesarik@suse.com
parent 8f5ae30d

kernel/dma/direct.c

+13 −18
Original line number Diff line number Diff line
@@ -120,7 +120,7 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, 
		gfp_t gfp, bool allow_highmem)

{

	int node = dev_to_node(dev);

	struct page *page = NULL;

	struct page *page;

	u64 phys_limit;



	WARN_ON_ONCE(!PAGE_ALIGNED(size));
@@ -131,30 +131,25 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, 
	gfp |= dma_direct_optimal_gfp_mask(dev, &phys_limit);

	page = dma_alloc_contiguous(dev, size, gfp);

	if (page) {

		if (!dma_coherent_ok(dev, page_to_phys(page), size) ||

		    (!allow_highmem && PageHighMem(page))) {

		if (dma_coherent_ok(dev, page_to_phys(page), size) &&

		    (allow_highmem || !PageHighMem(page)))

			return page;



		dma_free_contiguous(dev, page, size);

			page = NULL;

	}

	}

again:

	if (!page)

		page = alloc_pages_node(node, gfp, get_order(size));

	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {



	while ((page = alloc_pages_node(node, gfp, get_order(size)))

	       && !dma_coherent_ok(dev, page_to_phys(page), size)) {

		__free_pages(page, get_order(size));

		page = NULL;



		if (IS_ENABLED(CONFIG_ZONE_DMA32) &&

		    phys_limit < DMA_BIT_MASK(64) &&

		    !(gfp & (GFP_DMA32 | GFP_DMA))) {

		    !(gfp & (GFP_DMA32 | GFP_DMA)))

			gfp |= GFP_DMA32;

			goto again;

		}



		if (IS_ENABLED(CONFIG_ZONE_DMA) && !(gfp & GFP_DMA)) {

		else if (IS_ENABLED(CONFIG_ZONE_DMA) && !(gfp & GFP_DMA))

			gfp = (gfp & ~GFP_DMA32) | GFP_DMA;

			goto again;

		}

		else

			return NULL;

	}



	return page;