[RFC 07/11] iommu: Use IOMMU_DOMAIN_MIXED typed domain when IOMMU translates MSI

[Eric Auger]

If the IOMMU advertises IOMMU_CAP_TRANSLATE_MSI choose
IOMMU_DOMAIN_MIXED domain type instead of IOMMU_DOMAIN_UNMANAGED
to allow transparent allocation of MSI frame IOVAs.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
 drivers/iommu/iommu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 617cb2b..8b4b90c 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1069,7 +1069,10 @@ static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
 
 struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
 {
-	return __iommu_domain_alloc(bus, IOMMU_DOMAIN_UNMANAGED);
+	if (bus->iommu_ops->capable(IOMMU_CAP_TRANSLATE_MSI))
+		return __iommu_domain_alloc(bus, IOMMU_DOMAIN_MIXED);
+	else
+		return __iommu_domain_alloc(bus, IOMMU_DOMAIN_UNMANAGED);
 }
 EXPORT_SYMBOL_GPL(iommu_domain_alloc);
 
-- 
1.9.1