dma-direct: refine dma_direct_alloc zone selection (7d21ee4c) · Commits · 戴 / test

kernel/dma/direct.c

+21 −10

Original line number	Original line	Diff line number	Diff line
	@@ -69,6 +69,22 @@ u64 dma_direct_get_required_mask(struct device *dev)
	return (1ULL << (fls64(max_dma) - 1)) * 2 - 1;		return (1ULL << (fls64(max_dma) - 1)) * 2 - 1;
	}		}

			static gfp_t __dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
			u64 *phys_mask)
			{
			if (force_dma_unencrypted())
			*phys_mask = __dma_to_phys(dev, dma_mask);
			else
			*phys_mask = dma_to_phys(dev, dma_mask);

			/* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
			if (*phys_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
			return GFP_DMA;
			if (*phys_mask <= DMA_BIT_MASK(32))
			return GFP_DMA32;
			return 0;
			}

	static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)		static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
	{		{
	return phys_to_dma_direct(dev, phys) + size - 1 <=		return phys_to_dma_direct(dev, phys) + size - 1 <=
	@@ -81,17 +97,13 @@ void dma_direct_alloc_pages(struct device dev, size_t size,
	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;		unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
	int page_order = get_order(size);		int page_order = get_order(size);
	struct page *page = NULL;		struct page *page = NULL;
			u64 phys_mask;
	void *ret;		void *ret;

	/* we always manually zero the memory once we are done: */		/* we always manually zero the memory once we are done: */
	gfp &= ~__GFP_ZERO;		gfp &= ~__GFP_ZERO;
			gfp \|= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
	/* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */		&phys_mask);
	if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
	gfp \|= GFP_DMA;
	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
	gfp \|= GFP_DMA32;

	again:		again:
	/* CMA can be used only in the context which permits sleeping */		/* CMA can be used only in the context which permits sleeping */
	if (gfpflags_allow_blocking(gfp)) {		if (gfpflags_allow_blocking(gfp)) {
	@@ -110,15 +122,14 @@ again:
	page = NULL;		page = NULL;

	if (IS_ENABLED(CONFIG_ZONE_DMA32) &&		if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
	dev->coherent_dma_mask < DMA_BIT_MASK(64) &&		phys_mask < DMA_BIT_MASK(64) &&
	!(gfp & (GFP_DMA32 \| GFP_DMA))) {		!(gfp & (GFP_DMA32 \| GFP_DMA))) {
	gfp \|= GFP_DMA32;		gfp \|= GFP_DMA32;
	goto again;		goto again;
	}		}

	if (IS_ENABLED(CONFIG_ZONE_DMA) &&		if (IS_ENABLED(CONFIG_ZONE_DMA) &&
	dev->coherent_dma_mask < DMA_BIT_MASK(32) &&		phys_mask < DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) {
	!(gfp & GFP_DMA)) {
	gfp = (gfp & ~GFP_DMA32) \| GFP_DMA;		gfp = (gfp & ~GFP_DMA32) \| GFP_DMA;
	goto again;		goto again;
	}		}

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