On Mon, 2019-12-02 at 11:58 -0800, Jacob Pan wrote:
> Use combined macros for_each_svm_dev() to simplify SVM device iteration
> and error checking.
[]
> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
[]
> @@ -427,40 +430,36 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
[]
> + for_each_svm_dev(sdev, svm, dev) {
> + ret = 0;
> + sdev->users--;
> + if (!sdev->users) {
This might be better by reducing indentation here too
if (sdev->users)
break;
> + list_del_rcu(&sdev->list);
to reduce indentation 1 level below this
> + /* Flush the PASID cache and IOTLB for this device.
> + * Note that we do depend on the hardware *not* using
> + * the PASID any more. Just as we depend on other
> + * devices never using PASIDs that they have no right
> + * to use. We have a *shared* PASID table, because it's
> + * large and has to be physically contiguous. So it's
> + * hard to be as defensive as we might like. */
> + intel_pasid_tear_down_entry(iommu, dev, svm->pasid);
> + intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
> + kfree_rcu(sdev, rcu);
> +
> + if (list_empty(&svm->devs)) {
> + ioasid_free(svm->pasid);
> + if (svm->mm)
> + mmu_notifier_unregister(&svm->notifier,
> svm->mm);
> + list_del(&svm->list);
> + /* We mandate that no page faults may be
> outstanding
> + * for the PASID when intel_svm_unbind_mm() is
> called.
> + * If that is not obeyed, subtle errors will
> happen.
> + * Let's make them less subtle... */
> + memset(svm, 0x6b, sizeof(*svm));
> + kfree(svm);
> }
> - break;
> }
> + break;
> }
> out:
> mutex_unlock(&pasid_mutex);
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
