powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests (edea902c) · Commits · 戴 / test

Secure guest memory is inacessible to devices so regular DMA isn't possible. In that case set devices' dma_map_ops to NULL so that the generic DMA code path will use SWIOTLB to bounce buffers for DMA. Signed-off-by:

Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by:

Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-14-bauerman@linux.ibm.com

arch/powerpc/platforms/pseries/iommu.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@
		#include <asm/udbg.h>
		#include <asm/mmzone.h>
		#include <asm/plpar_wrappers.h>
		#include <asm/svm.h>

		#include "pseries.h"

		@@ -1319,6 +1320,14 @@ void iommu_init_early_pSeries(void)
		of_reconfig_notifier_register(&iommu_reconfig_nb);
		register_memory_notifier(&iommu_mem_nb);

		/*
		* Secure guest memory is inacessible to devices so regular DMA isn't
		* possible.
		*
		* In that case keep devices' dma_map_ops as NULL so that the generic
		* DMA code path will use SWIOTLB to bounce buffers for DMA.
		*/
		if (!is_secure_guest())
		set_pci_dma_ops(&dma_iommu_ops);
		}

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