iommu/virtio: Use accessor functions for iommu private data

Make use of dev_iommu_priv_set/get() functions.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20200326150841.10083-16-joro@8bytes.org

drivers/iommu/virtio-iommu.c

@@ -466,7 +466,7 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev)
 	struct virtio_iommu_req_probe *probe;
 	struct virtio_iommu_probe_property *prop;
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-	struct viommu_endpoint *vdev = fwspec->iommu_priv;
+	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
 
 	if (!fwspec->num_ids)
 		return -EINVAL;
@@ -648,7 +648,7 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	int ret = 0;
 	struct virtio_iommu_req_attach req;
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-	struct viommu_endpoint *vdev = fwspec->iommu_priv;
+	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
 	struct viommu_domain *vdomain = to_viommu_domain(domain);
 
 	mutex_lock(&vdomain->mutex);
@@ -807,8 +807,7 @@ static void viommu_iotlb_sync(struct iommu_domain *domain,
 static void viommu_get_resv_regions(struct device *dev, struct list_head *head)
 {
 	struct iommu_resv_region *entry, *new_entry, *msi = NULL;
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-	struct viommu_endpoint *vdev = fwspec->iommu_priv;
+	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
 	int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
 
 	list_for_each_entry(entry, &vdev->resv_regions, list) {
@@ -876,7 +875,7 @@ static int viommu_add_device(struct device *dev)
 	vdev->dev = dev;
 	vdev->viommu = viommu;
 	INIT_LIST_HEAD(&vdev->resv_regions);
-	fwspec->iommu_priv = vdev;
+	dev_iommu_priv_set(dev, vdev);
 
 	if (viommu->probe_size) {
 		/* Get additional information for this endpoint */
@@ -920,7 +919,7 @@ static void viommu_remove_device(struct device *dev)
 	if (!fwspec || fwspec->ops != &viommu_ops)
 		return;
 
-	vdev = fwspec->iommu_priv;
+	vdev = dev_iommu_priv_get(dev);
 
 	iommu_group_remove_device(dev);
 	iommu_device_unlink(&vdev->viommu->iommu, dev);