[PATCH v7 06/16] iommu/vt-d: Remove get_task_mm() in bind_gpasid()

[Liu Yi L <yi.l.liu@intel.com>]

This patch is to address a REVISIT. As ioasid_set is added to domain,
upper layer/VFIO can set ioasid_set to iommu driver, and track the
PASID ownership, so no need to get_task_mm() in intel_svm_bind_gpasid().

Cc: Kevin Tian <kevin.tian@intel.com>
CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
---
 drivers/iommu/intel/svm.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 519eabb..d3cf52b 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -400,12 +400,6 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
 			ret = -ENOMEM;
 			goto out;
 		}
-		/* REVISIT: upper layer/VFIO can track host process that bind
-		 * the PASID. ioasid_set = mm might be sufficient for vfio to
-		 * check pasid VMM ownership. We can drop the following line
-		 * once VFIO and IOASID set check is in place.
-		 */
-		svm->mm = get_task_mm(current);
 		svm->pasid = data->hpasid;
 		if (data->flags & IOMMU_SVA_GPASID_VAL) {
 			svm->gpasid = data->gpasid;
@@ -420,7 +414,6 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
 		INIT_WORK(&svm->work, intel_svm_free_async_fn);
 		ioasid_attach_data(data->hpasid, svm);
 		INIT_LIST_HEAD_RCU(&svm->devs);
-		mmput(svm->mm);
 	}
 	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
 	if (!sdev) {
-- 
2.7.4