Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
dma-direct: prevent SWIOTLB path when DMA_ATTR_REQUIRE_COHERENT is set
DMA_ATTR_REQUIRE_COHERENT indicates that SWIOTLB must not be used.
Ensure the SWIOTLB path is declined whenever the DMA direct path is
selected.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20260316-dma-debug-overlap-v3-5-1dde90a7f08b@nvidia.com
authored by
Leon Romanovsky
and committed by
Marek Szyprowski
2536617f
e6a58fa2
+4
-3
+4
-3
kernel/dma/direct.h
+4
-3
kernel/dma/direct.h
···
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dma_addr_t dma_addr;
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if (is_swiotlb_force_bounce(dev)) {
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-
if (attrs & DMA_ATTR_MMIO)
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+
if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT))
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return DMA_MAPPING_ERROR;
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return swiotlb_map(dev, phys, size, dir, attrs);
···
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dma_addr = phys_to_dma(dev, phys);
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if (unlikely(!dma_capable(dev, dma_addr, size, true)) ||
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dma_kmalloc_needs_bounce(dev, size, dir)) {
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-
if (is_swiotlb_active(dev))
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+
if (is_swiotlb_active(dev) &&
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!(attrs & DMA_ATTR_REQUIRE_COHERENT))
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return swiotlb_map(dev, phys, size, dir, attrs);
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goto err_overflow;
···
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{
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phys_addr_t phys;
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-
if (attrs & DMA_ATTR_MMIO)
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+
if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT))
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/* nothing to do: uncached and no swiotlb */
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return;
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