[PATCH V4 12/18] iommu/vt-d: Remove mm reference for guest SVA

Jacob Pan
2021-02-28T06:40:50Z

Now that IOASID core keeps track of the IOASID to mm_struct ownership in
the forms of ioasid_set with IOASID_SET_TYPE_MM token type, there is no
need to keep the same mapping in VT-d driver specific data. Native SVM
usage is not affected by the change.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.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 c469c24d23f5..f75699ddb923 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -363,12 +363,6 @@ 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;
@@ -376,7 +370,6 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
}
ioasid_attach_data(data->hpasid, svm);
INIT_LIST_HEAD_RCU(&svm->devs);
- mmput(svm->mm);
}
sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
if (!sdev) {
--
2.25.1