1 files changed, 151 insertions, 3 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8be047a4808f..7de0e29db333 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -199,7 +199,7 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
 	dev->iommu->iommu_dev = iommu_dev;
 
 	group = iommu_group_get_for_dev(dev);
-	if (!IS_ERR(group)) {
+	if (IS_ERR(group)) {
 		ret = PTR_ERR(group);
 		goto out_release;
 	}
@@ -1599,6 +1599,37 @@ static int add_iommu_group(struct device *dev, void *data)
 	return ret;
 }
 
+static int probe_iommu_group(struct device *dev, void *data)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+	struct list_head *group_list = data;
+	int ret;
+
+	if (!dev_iommu_get(dev))
+		return -ENOMEM;
+
+	if (!try_module_get(ops->owner)) {
+		ret = -EINVAL;
+		goto err_free_dev_iommu;
+	}
+
+	ret = __iommu_probe_device(dev, group_list);
+	if (ret)
+		goto err_module_put;
+
+	return 0;
+
+err_module_put:
+	module_put(ops->owner);
+err_free_dev_iommu:
+	dev_iommu_free(dev);
+
+	if (ret == -ENODEV)
+		ret = 0;
+
+	return ret;
+}
+
 static int remove_iommu_group(struct device *dev, void *data)
 {
 	iommu_release_device(dev);
@@ -1658,10 +1689,127 @@ static int iommu_bus_notifier(struct notifier_block *nb,
 	return 0;
 }
 
+struct __group_domain_type {
+	struct device *dev;
+	unsigned int type;
+};
+
+static int probe_get_default_domain_type(struct device *dev, void *data)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+	struct __group_domain_type *gtype = data;
+	unsigned int type = 0;
+
+	if (ops->def_domain_type)
+		type = ops->def_domain_type(dev);
+
+	if (type) {
+		if (gtype->type && gtype->type != type) {
+			dev_warn(dev, "Device needs domain type %s, but device %s in the same iommu group requires type %s - using default\n",
+				 iommu_domain_type_str(type),
+				 dev_name(gtype->dev),
+				 iommu_domain_type_str(gtype->type));
+			gtype->type = 0;
+		}
+
+		if (!gtype->dev) {
+			gtype->dev  = dev;
+			gtype->type = type;
+		}
+	}
+
+	return 0;
+}
+
+static void probe_alloc_default_domain(struct bus_type *bus,
+				       struct iommu_group *group)
+{
+	struct __group_domain_type gtype;
+
+	memset(&gtype, 0, sizeof(gtype));
+
+	/* Ask for default domain requirements of all devices in the group */
+	__iommu_group_for_each_dev(group, &gtype,
+				   probe_get_default_domain_type);
+
+	if (!gtype.type)
+		gtype.type = iommu_def_domain_type;
+
+	iommu_group_alloc_default_domain(bus, group, gtype.type);
+}
+
+static int iommu_group_do_dma_attach(struct device *dev, void *data)
+{
+	struct iommu_domain *domain = data;
+	const struct iommu_ops *ops;
+	int ret;
+
+	ret = __iommu_attach_device(domain, dev);
+
+	ops = domain->ops;
+
+	if (ret == 0 && ops->probe_finalize)
+		ops->probe_finalize(dev);
+
+	return ret;
+}
+
+static int __iommu_group_dma_attach(struct iommu_group *group)
+{
+	return __iommu_group_for_each_dev(group, group->default_domain,
+					  iommu_group_do_dma_attach);
+}
+
+static int bus_iommu_probe(struct bus_type *bus)
+{
+	const struct iommu_ops *ops = bus->iommu_ops;
+	int ret;
+
+	if (ops->probe_device) {
+		struct iommu_group *group, *next;
+		LIST_HEAD(group_list);
+
+		/*
+		 * This code-path does not allocate the default domain when
+		 * creating the iommu group, so do it after the groups are
+		 * created.
+		 */
+		ret = bus_for_each_dev(bus, NULL, &group_list, probe_iommu_group);
+		if (ret)
+			return ret;
+
+		list_for_each_entry_safe(group, next, &group_list, entry) {
+			/* Remove item from the list */
+			list_del_init(&group->entry);
+
+			mutex_lock(&group->mutex);
+
+			/* Try to allocate default domain */
+			probe_alloc_default_domain(bus, group);
+
+			if (!group->default_domain) {
+				mutex_unlock(&group->mutex);
+				continue;
+			}
+
+			ret = __iommu_group_dma_attach(group);
+
+			mutex_unlock(&group->mutex);
+
+			if (ret)
+				break;
+		}
+	} else {
+		ret = bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
+	}
+
+	return ret;
+}
+
 static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
 {
-	int err;
 	struct notifier_block *nb;
+	int err;
 
 	nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
 	if (!nb)
@@ -1673,7 +1821,7 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
 	if (err)
 		goto out_free;
 
-	err = bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
+	err = bus_iommu_probe(bus);
 	if (err)
 		goto out_err;