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-rw-r--r--Documentation/ABI/testing/sysfs-kernel-iommu_groups18
1 files changed, 9 insertions, 9 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups
index 0fedbb0f94e4..b15af6a5bc08 100644
--- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups
+++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups
@@ -25,14 +25,10 @@ Description: /sys/kernel/iommu_groups/reserved_regions list IOVA
the base IOVA, the second is the end IOVA and the third
field describes the type of the region.
-What: /sys/kernel/iommu_groups/reserved_regions
-Date: June 2019
-KernelVersion: v5.3
-Contact: Eric Auger <eric.auger@redhat.com>
-Description: In case an RMRR is used only by graphics or USB devices
- it is now exposed as "direct-relaxable" instead of "direct".
- In device assignment use case, for instance, those RMRR
- are considered to be relaxable and safe.
+ Since kernel 5.3, in case an RMRR is used only by graphics or
+ USB devices it is now exposed as "direct-relaxable" instead
+ of "direct". In device assignment use case, for instance,
+ those RMRR are considered to be relaxable and safe.
What: /sys/kernel/iommu_groups/<grp_id>/type
Date: November 2020
@@ -46,8 +42,12 @@ Description: /sys/kernel/iommu_groups/<grp_id>/type shows the type of default
======== ======================================================
DMA All the DMA transactions from the device in this group
are translated by the iommu.
+ DMA-FQ As above, but using batched invalidation to lazily
+ remove translations after use. This may offer reduced
+ overhead at the cost of reduced memory protection.
identity All the DMA transactions from the device in this group
- are not translated by the iommu.
+ are not translated by the iommu. Maximum performance
+ but zero protection.
auto Change to the type the device was booted with.
======== ======================================================