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

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commit d862b44133b7a1d7de25288e09eabf4df415e971 upstream.

This reverts commit edea902c1c1efb855f77e041f9daf1abe7a9768a.

At the time the change allowed direct DMA ops for secure VMs; however
since then we switched on using SWIOTLB backed with IOMMU (direct mapping)
and to make this work, we need dma_iommu_ops which handles all cases
including TCE mapping I/O pages in the presence of an IOMMU.

Fixes: edea902c1c1e ("powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests")
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[aik: added "revert" and "fixes:"]
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Tested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191216041924.42318-2-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ram Pai 2019-12-16 15:19:21 +11:00 committed by Greg Kroah-Hartman
parent 45c764da00
commit 6d7edac146
1 changed files with 1 additions and 10 deletions
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11
arch/powerpc/platforms/pseries/iommu.c
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@ -36,7 +36,6 @@
#include <asm/udbg.h>
#include <asm/mmzone.h>
#include <asm/plpar_wrappers.h>
#include <asm/svm.h>
#include "pseries.h"
@ -1320,15 +1319,7 @@ 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);
set_pci_dma_ops(&dma_iommu_ops);
}
static int __init disable_multitce(char *str)