[PATCH v10 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 is 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 03c88cee806f..50c1477a6c2e 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -94,7 +94,7 @@ choice
 	prompt "IOMMU default DMA mode"
 	depends on IOMMU_API
 
-	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