This is a note to let you know that I've just added the patch titled
dma-direct: factor out a helper for DMA_ATTR_NO_KERNEL_MAPPING allocations
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dma-direct-factor-out-a-helper-for-dma_attr_no_kerne.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a33341a714f4b75ba87f69d48cc95e691cc484a0
Author: Christoph Hellwig <hch@xxxxxx>
Date: Mon Oct 18 13:08:07 2021 +0200
dma-direct: factor out a helper for DMA_ATTR_NO_KERNEL_MAPPING allocations
[ Upstream commit d541ae55d538265861ef729a64d2d816d34ef1e2 ]
Split the code for DMA_ATTR_NO_KERNEL_MAPPING allocations into a separate
helper to make dma_direct_alloc a little more readable.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 4c6c5e0635e3..ddaac01f2cba 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -149,6 +149,24 @@ static void *dma_direct_alloc_from_pool(struct device *dev, size_t size,
return ret;
}
+static void *dma_direct_alloc_no_mapping(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp)
+{
+ struct page *page;
+
+ page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
+ if (!page)
+ return NULL;
+
+ /* remove any dirty cache lines on the kernel alias */
+ if (!PageHighMem(page))
+ arch_dma_prep_coherent(page, size);
+
+ /* return the page pointer as the opaque cookie */
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
+ return page;
+}
+
void *dma_direct_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
@@ -161,17 +179,8 @@ void *dma_direct_alloc(struct device *dev, size_t size,
gfp |= __GFP_NOWARN;
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) {
- page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
- if (!page)
- return NULL;
- /* remove any dirty cache lines on the kernel alias */
- if (!PageHighMem(page))
- arch_dma_prep_coherent(page, size);
- *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
- /* return the page pointer as the opaque cookie */
- return page;
- }
+ !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev))
+ return dma_direct_alloc_no_mapping(dev, size, dma_handle, gfp);
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
