drivers/iommu: Initialise module 'owner' field in iommu_device_set_ops()

Requiring each IOMMU driver to initialise the 'owner' field of their
'struct iommu_ops' is error-prone and easily forgotten. Follow the
example set by PCI and USB by assigning THIS_MODULE automatically when
registering the ops structure with IOMMU core.
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NWill Deacon <will@kernel.org>

drivers/iommu/arm-smmu-v3.c

@@ -2733,7 +2733,6 @@ static struct iommu_ops arm_smmu_ops = {
 	.get_resv_regions	= arm_smmu_get_resv_regions,
 	.put_resv_regions	= arm_smmu_put_resv_regions,
 	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
-	.owner			= THIS_MODULE,
 };
 
 /* Probing and initialisation functions */

drivers/iommu/arm-smmu.c

@@ -1623,7 +1623,6 @@ static struct iommu_ops arm_smmu_ops = {
 	.get_resv_regions	= arm_smmu_get_resv_regions,
 	.put_resv_regions	= arm_smmu_put_resv_regions,
 	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
-	.owner			= THIS_MODULE,
 };
 
 static void arm_smmu_device_reset(struct arm_smmu_device *smmu)

include/linux/iommu.h

@@ -388,12 +388,19 @@ void iommu_device_sysfs_remove(struct iommu_device *iommu);
 int  iommu_device_link(struct iommu_device   *iommu, struct device *link);
 void iommu_device_unlink(struct iommu_device *iommu, struct device *link);
 
-static inline void iommu_device_set_ops(struct iommu_device *iommu,
-					const struct iommu_ops *ops)
+static inline void __iommu_device_set_ops(struct iommu_device *iommu,
+					  const struct iommu_ops *ops)
 {
 	iommu->ops = ops;
 }
 
+#define iommu_device_set_ops(iommu, ops)				\
+do {									\
+	struct iommu_ops *__ops = (struct iommu_ops *)(ops);		\
+	__ops->owner = THIS_MODULE;					\
+	__iommu_device_set_ops(iommu, __ops);				\
+} while (0)
+
 static inline void iommu_device_set_fwnode(struct iommu_device *iommu,
 					   struct fwnode_handle *fwnode)
 {