powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests

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
This commit is contained in:
Thiago Jung Bauermann 2019-08-19 23:13:23 -03:00 committed by Michael Ellerman
parent 4edaac512c
commit edea902c1c

View File

@ -36,6 +36,7 @@
#include <asm/udbg.h>
#include <asm/mmzone.h>
#include <asm/plpar_wrappers.h>
#include <asm/svm.h>
#include "pseries.h"
@ -1319,7 +1320,15 @@ 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)