[PATCH v8 6/7] iommu/amd: add support for IOMMU default DMA mode build options

Zhen Lei
2019-05-30T03:48:30Z

The default DMA mode of AMD IOMMU is LAZY, this patch make it can be set
to STRICT at build time. It can be overridden by boot option.

There is no functional change.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
drivers/iommu/Kconfig | 2 +-
drivers/iommu/amd_iommu_init.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index af580274b7c5270..f6c030433d38048 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -79,7 +79,7 @@ choice
prompt "IOMMU default DMA mode"
depends on IOMMU_API
default IOMMU_DEFAULT_PASSTHROUGH if (PPC_POWERNV && PCI)
- default IOMMU_DEFAULT_LAZY if (INTEL_IOMMU || S390_IOMMU)
+ default IOMMU_DEFAULT_LAZY if (AMD_IOMMU || INTEL_IOMMU || S390_IOMMU)
default IOMMU_DEFAULT_STRICT
help
This option allows IOMMU DMA mode to be chose at build time, to
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index f977df90d2a4912..6b0bfa43f6faa32 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -166,7 +166,8 @@ struct ivmd_header {
to handle */
LIST_HEAD(amd_iommu_unity_map); /* a list of required unity mappings
we find in ACPI */
-bool amd_iommu_unmap_flush; /* if true, flush on every unmap */
+bool amd_iommu_unmap_flush = IS_ENABLED(CONFIG_IOMMU_DEFAULT_STRICT);
+ /* if true, flush on every unmap */

LIST_HEAD(amd_iommu_list); /* list of all AMD IOMMUs in the
system */
--
1.8.3