[PATCH v4 13/16] powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests
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STALE2591d
LANDED
From: Thiago Jung Bauermann <hidden>
Date: 2019-08-20 02:16:56
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Revision v4 of 3 in this series; landed in mainline as edea902c1c1e on 2019-08-29.
Revisions (3)
- v2 [diff vs current]
- v3 [diff vs current]
- v4 current
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 <redacted> --- arch/powerpc/platforms/pseries/iommu.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 889dc2e44b89..8d9c2b17ad54 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c@@ -36,6 +36,7 @@ #include <asm/udbg.h> #include <asm/mmzone.h> #include <asm/plpar_wrappers.h> +#include <asm/svm.h> #include "pseries.h"
@@ -1318,7 +1319,15 @@ void iommu_init_early_pSeries(void) of_reconfig_notifier_register(&iommu_reconfig_nb); register_memory_notifier(&iommu_mem_nb); - set_pci_dma_ops(&dma_iommu_ops); + /* + * 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); } static int __init disable_multitce(char *str)