[PATCH v6 07/11] vfio: Set DMA ownership for VFIO devices

[Lu Baolu]

Claim group dma ownership when an IOMMU group is set to a container,
and release the dma ownership once the iommu group is unset from the
container.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c     |  1 +
 drivers/vfio/pci/vfio_pci.c           |  1 +
 drivers/vfio/platform/vfio_amba.c     |  1 +
 drivers/vfio/platform/vfio_platform.c |  1 +
 drivers/vfio/vfio.c                   | 10 +++++++++-
 5 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 6e2e62c6f47a..3feff729f3ce 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -588,6 +588,7 @@ static struct fsl_mc_driver vfio_fsl_mc_driver = {
 		.name	= "vfio-fsl-mc",
 		.owner	= THIS_MODULE,
 	},
+	.driver_managed_dma = true,
 };
 
 static int __init vfio_fsl_mc_driver_init(void)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index a5ce92beb655..941909d3918b 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -193,6 +193,7 @@ static struct pci_driver vfio_pci_driver = {
 	.remove			= vfio_pci_remove,
 	.sriov_configure	= vfio_pci_sriov_configure,
 	.err_handler		= &vfio_pci_core_err_handlers,
+	.driver_managed_dma	= true,
 };
 
 static void __init vfio_pci_fill_ids(void)
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
index badfffea14fb..1aaa4f721bd2 100644
--- a/drivers/vfio/platform/vfio_amba.c
+++ b/drivers/vfio/platform/vfio_amba.c
@@ -95,6 +95,7 @@ static struct amba_driver vfio_amba_driver = {
 		.name = "vfio-amba",
 		.owner = THIS_MODULE,
 	},
+	.driver_managed_dma = true,
 };
 
 module_amba_driver(vfio_amba_driver);
diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
index 68a1c87066d7..04f40c5acfd6 100644
--- a/drivers/vfio/platform/vfio_platform.c
+++ b/drivers/vfio/platform/vfio_platform.c
@@ -76,6 +76,7 @@ static struct platform_driver vfio_platform_driver = {
 	.driver	= {
 		.name	= "vfio-platform",
 	},
+	.driver_managed_dma = true,
 };
 
 module_platform_driver(vfio_platform_driver);
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 735d1d344af9..df9d4b60e5ae 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1198,6 +1198,8 @@ static void __vfio_group_unset_container(struct vfio_group *group)
 		driver->ops->detach_group(container->iommu_data,
 					  group->iommu_group);
 
+	iommu_group_release_dma_owner(group->iommu_group);
+
 	group->container = NULL;
 	wake_up(&group->container_q);
 	list_del(&group->container_next);
@@ -1282,13 +1284,19 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd)
 		goto unlock_out;
 	}
 
+	ret = iommu_group_claim_dma_owner(group->iommu_group, f.file);
+	if (ret)
+		goto unlock_out;
+
 	driver = container->iommu_driver;
 	if (driver) {
 		ret = driver->ops->attach_group(container->iommu_data,
 						group->iommu_group,
 						group->type);
-		if (ret)
+		if (ret) {
+			iommu_group_release_dma_owner(group->iommu_group);
 			goto unlock_out;
+		}
 	}
 
 	group->container = container;
-- 
2.25.1