[PATCH v11 3/3] iommu/amd: Add support for IOMMU default DMA mode build options

[John Garry]

From: Zhen Lei <thunder.leizhen@xxxxxxxxxx>

The default DMA mode lazy, but allow this to be set to strict mode at
build time. It may still be overridden by the relevant boot option.

Also make IOMMU_DEFAULT_LAZY default for when AMD_IOMMU config is set.

[jpg: Rebase for relocated file]
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
 drivers/iommu/Kconfig    | 2 +-
 drivers/iommu/amd/init.c | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index b68ec7ed23c0..6d99150050b9 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -95,7 +95,7 @@ choice
 	depends on IOMMU_API
 	depends on X86 || IA64 || X86_64 || ARM || ARM64
 
-	default IOMMU_DEFAULT_LAZY if INTEL_IOMMU
+	default IOMMU_DEFAULT_LAZY if (AMD_IOMMU || INTEL_IOMMU)
 	default IOMMU_DEFAULT_STRICT
 	help
 	  This option allows an IOMMU DMA mode to be chosen at build time, to
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index d006724f4dc2..af662fc37cbe 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -160,7 +160,8 @@ u16 amd_iommu_last_bdf;			/* largest PCI device id we have
 					   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 */
+/* if true, flush on every unmap */
+bool amd_iommu_unmap_flush = IS_ENABLED(CONFIG_IOMMU_DEFAULT_STRICT);
 
 LIST_HEAD(amd_iommu_list);		/* list of all AMD IOMMUs in the
 					   system */
-- 
2.26.2