1 files changed, 25 insertions, 21 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3e3528436e0b..2b471419e26c 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -152,9 +152,9 @@ void iommu_device_unregister(struct iommu_device *iommu)
 }
 EXPORT_SYMBOL_GPL(iommu_device_unregister);
 
-static struct iommu_param *iommu_get_dev_param(struct device *dev)
+static struct dev_iommu *dev_iommu_get(struct device *dev)
 {
-	struct iommu_param *param = dev->iommu_param;
+	struct dev_iommu *param = dev->iommu;
 
 	if (param)
 		return param;
@@ -164,14 +164,14 @@ static struct iommu_param *iommu_get_dev_param(struct device *dev)
 		return NULL;
 
 	mutex_init(&param->lock);
-	dev->iommu_param = param;
+	dev->iommu = param;
 	return param;
 }
 
-static void iommu_free_dev_param(struct device *dev)
+static void dev_iommu_free(struct device *dev)
 {
-	kfree(dev->iommu_param);
-	dev->iommu_param = NULL;
+	kfree(dev->iommu);
+	dev->iommu = NULL;
 }
 
 int iommu_probe_device(struct device *dev)
@@ -183,7 +183,7 @@ int iommu_probe_device(struct device *dev)
 	if (!ops)
 		return -EINVAL;
 
-	if (!iommu_get_dev_param(dev))
+	if (!dev_iommu_get(dev))
 		return -ENOMEM;
 
 	if (!try_module_get(ops->owner)) {
@@ -200,7 +200,7 @@ int iommu_probe_device(struct device *dev)
 err_module_put:
 	module_put(ops->owner);
 err_free_dev_param:
-	iommu_free_dev_param(dev);
+	dev_iommu_free(dev);
 	return ret;
 }
 
@@ -211,9 +211,9 @@ void iommu_release_device(struct device *dev)
 	if (dev->iommu_group)
 		ops->remove_device(dev);
 
-	if (dev->iommu_param) {
+	if (dev->iommu) {
 		module_put(ops->owner);
-		iommu_free_dev_param(dev);
+		dev_iommu_free(dev);
 	}
 }
 
@@ -972,7 +972,7 @@ int iommu_register_device_fault_handler(struct device *dev,
 					iommu_dev_fault_handler_t handler,
 					void *data)
 {
-	struct iommu_param *param = dev->iommu_param;
+	struct dev_iommu *param = dev->iommu;
 	int ret = 0;
 
 	if (!param)
@@ -1015,7 +1015,7 @@ EXPORT_SYMBOL_GPL(iommu_register_device_fault_handler);
  */
 int iommu_unregister_device_fault_handler(struct device *dev)
 {
-	struct iommu_param *param = dev->iommu_param;
+	struct dev_iommu *param = dev->iommu;
 	int ret = 0;
 
 	if (!param)
@@ -1055,7 +1055,7 @@ EXPORT_SYMBOL_GPL(iommu_unregister_device_fault_handler);
  */
 int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt)
 {
-	struct iommu_param *param = dev->iommu_param;
+	struct dev_iommu *param = dev->iommu;
 	struct iommu_fault_event *evt_pending = NULL;
 	struct iommu_fault_param *fparam;
 	int ret = 0;
@@ -1104,7 +1104,7 @@ int iommu_page_response(struct device *dev,
 	int ret = -EINVAL;
 	struct iommu_fault_event *evt;
 	struct iommu_fault_page_request *prm;
-	struct iommu_param *param = dev->iommu_param;
+	struct dev_iommu *param = dev->iommu;
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 
 	if (!domain || !domain->ops->page_response)
@@ -2405,7 +2405,11 @@ int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
 	if (fwspec)
 		return ops == fwspec->ops ? 0 : -EINVAL;
 
-	fwspec = kzalloc(sizeof(*fwspec), GFP_KERNEL);
+	if (!dev_iommu_get(dev))
+		return -ENOMEM;
+
+	/* Preallocate for the overwhelmingly common case of 1 ID */
+	fwspec = kzalloc(struct_size(fwspec, ids, 1), GFP_KERNEL);
 	if (!fwspec)
 		return -ENOMEM;
 
@@ -2432,15 +2436,15 @@ 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_get(dev);
-	size_t size;
-	int i;
+	int i, new_num;
 
 	if (!fwspec)
 		return -EINVAL;
 
-	size = offsetof(struct iommu_fwspec, ids[fwspec->num_ids + num_ids]);
-	if (size > sizeof(*fwspec)) {
-		fwspec = krealloc(fwspec, size, GFP_KERNEL);
+	new_num = fwspec->num_ids + num_ids;
+	if (new_num > 1) {
+		fwspec = krealloc(fwspec, struct_size(fwspec, ids, new_num),
+				  GFP_KERNEL);
 		if (!fwspec)
 			return -ENOMEM;
 
@@ -2450,7 +2454,7 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
 	for (i = 0; i < num_ids; i++)
 		fwspec->ids[fwspec->num_ids + i] = ids[i];
 
-	fwspec->num_ids += num_ids;
+	fwspec->num_ids = new_num;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);