iommu: Introduce wrappers around dev->iommu_fwspec

These wrappers will be used to easily change the location of
the field later when all users are converted.
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/iommu.c

@@ -1976,7 +1976,7 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
 int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
 		      const struct iommu_ops *ops)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
 	if (fwspec)
 		return ops == fwspec->ops ? 0 : -EINVAL;
@@ -1988,26 +1988,26 @@ int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
 	of_node_get(to_of_node(iommu_fwnode));
 	fwspec->iommu_fwnode = iommu_fwnode;
 	fwspec->ops = ops;
-	dev->iommu_fwspec = fwspec;
+	dev_iommu_fwspec_set(dev, fwspec);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_init);
 
 void iommu_fwspec_free(struct device *dev)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
 	if (fwspec) {
 		fwnode_handle_put(fwspec->iommu_fwnode);
 		kfree(fwspec);
-		dev->iommu_fwspec = NULL;
+		dev_iommu_fwspec_set(dev, NULL);
 	}
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_free);
 
 int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	size_t size;
 	int i;
 
@@ -2016,11 +2016,11 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
 
 	size = offsetof(struct iommu_fwspec, ids[fwspec->num_ids + num_ids]);
 	if (size > sizeof(*fwspec)) {
-		fwspec = krealloc(dev->iommu_fwspec, size, GFP_KERNEL);
+		fwspec = krealloc(fwspec, size, GFP_KERNEL);
 		if (!fwspec)
 			return -ENOMEM;
 
-		dev->iommu_fwspec = fwspec;
+		dev_iommu_fwspec_set(dev, fwspec);
 	}
 
 	for (i = 0; i < num_ids; i++)

include/linux/iommu.h

@@ -398,6 +398,17 @@ void iommu_fwspec_free(struct device *dev);
 int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);
 const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode);
 
+static inline struct iommu_fwspec *dev_iommu_fwspec_get(struct device *dev)
+{
+	return dev->iommu_fwspec;
+}
+
+static inline void dev_iommu_fwspec_set(struct device *dev,
+					struct iommu_fwspec *fwspec)
+{
+	dev->iommu_fwspec = fwspec;
+}
+
 #else /* CONFIG_IOMMU_API */
 
 struct iommu_ops {};