iommu/vt-d: Remove redundant IOTLB flush

IOTLB flush already included in the PASID tear down and the page request
drain process. There is no need to flush again.
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20200516062101.29541-17-baolu.lu@linux.intel.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

drivers/iommu/intel-svm.c

@@ -209,11 +209,9 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
 	 * *has* to handle gracefully without affecting other processes.
 	 */
 	rcu_read_lock();
-	list_for_each_entry_rcu(sdev, &svm->devs, list) {
+	list_for_each_entry_rcu(sdev, &svm->devs, list)
 		intel_pasid_tear_down_entry(svm->iommu, sdev->dev,
 					    svm->pasid, true);
-		intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
-	}
 	rcu_read_unlock();
 
 }
@@ -403,7 +401,6 @@ int intel_svm_unbind_gpasid(struct device *dev, int pasid)
 			intel_pasid_tear_down_entry(iommu, dev,
 						    svm->pasid, false);
 			intel_svm_drain_prq(dev, svm->pasid);
-			intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
 			kfree_rcu(sdev, rcu);
 
 			if (list_empty(&svm->devs)) {
@@ -643,7 +640,6 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
 			intel_pasid_tear_down_entry(iommu, dev,
 						    svm->pasid, false);
 			intel_svm_drain_prq(dev, svm->pasid);
-			intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
 			kfree_rcu(sdev, rcu);
 
 			if (list_empty(&svm->devs)) {