Commit 28e4576d authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

dma-direct: add a dma_direct_use_pool helper 



Add a helper to check if a potentially blocking operation should
dip into the atomic pools.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarRobin Murphy <robin.murphy@arm.com>
parent aea7e2a8

kernel/dma/direct.c

+12 −6
Original line number Diff line number Diff line
@@ -156,6 +156,15 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, 
	return page;

}



/*

 * Check if a potentially blocking operations needs to dip into the atomic

 * pools for the given device/gfp.

 */

static bool dma_direct_use_pool(struct device *dev, gfp_t gfp)

{

	return !gfpflags_allow_blocking(gfp) && !is_swiotlb_for_alloc(dev);

}



static void *dma_direct_alloc_from_pool(struct device *dev, size_t size,

		dma_addr_t *dma_handle, gfp_t gfp)

{
@@ -235,8 +244,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, 
		 */

		remap = IS_ENABLED(CONFIG_DMA_DIRECT_REMAP);

		if (remap) {

			if (!gfpflags_allow_blocking(gfp) &&

			    !is_swiotlb_for_alloc(dev))

			if (dma_direct_use_pool(dev, gfp))

				return dma_direct_alloc_from_pool(dev, size,

						dma_handle, gfp);

		} else {
@@ -250,8 +258,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, 
	 * Decrypting memory may block, so allocate the memory from the atomic

	 * pools if we can't block.

	 */

	if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&

	    !is_swiotlb_for_alloc(dev))

	if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp))

		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);



	/* we always manually zero the memory once we are done */
@@ -360,8 +367,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size, 
	struct page *page;

	void *ret;



	if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&

	    !is_swiotlb_for_alloc(dev))

	if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp))

		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);



	page = __dma_direct_alloc_pages(dev, size, gfp);