[RFC,09/34] iommu: Keep a list of allocated groups in __iommu_probe_device()

Commit Message

Joerg Roedel April 7, 2020, 6:37 p.m. UTC

From: Joerg Roedel <[e-mail]>

This is needed to defer default_domain allocation for new IOMMU groups
until all devices have been added to the group.

Signed-off-by: Joerg Roedel <[e-mail]>
---
 drivers/iommu/iommu.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Patch

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 7a385c18e1a5..18eb3623bd00 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -44,6 +44,7 @@  struct iommu_group {
 	int id;
 	struct iommu_domain *default_domain;
 	struct iommu_domain *domain;
+	struct list_head entry;
 };
 
 struct group_device {
@@ -184,7 +185,7 @@  static void dev_iommu_free(struct device *dev)
 	dev->iommu = NULL;
 }
 
-static int __iommu_probe_device(struct device *dev)
+static int __iommu_probe_device(struct device *dev, struct list_head *group_list)
 {
 	const struct iommu_ops *ops = dev->bus->iommu_ops;
 	struct iommu_device *iommu_dev;
@@ -204,6 +205,9 @@  static int __iommu_probe_device(struct device *dev)
 	}
 	iommu_group_put(group);
 
+	if (group_list && !group->default_domain && list_empty(&group->entry))
+		list_add_tail(&group->entry, group_list);
+
 	iommu_device_link(iommu_dev, dev);
 
 	return 0;
@@ -234,7 +238,7 @@  int iommu_probe_device(struct device *dev)
 	if (ops->probe_device) {
 		struct iommu_group *group;
 
-		ret = __iommu_probe_device(dev);
+		ret = __iommu_probe_device(dev, NULL);
 
 		/*
 		 * Try to allocate a default domain - needs support from the
@@ -567,6 +571,7 @@  struct iommu_group *iommu_group_alloc(void)
 	group->kobj.kset = iommu_group_kset;
 	mutex_init(&group->mutex);
 	INIT_LIST_HEAD(&group->devices);
+	INIT_LIST_HEAD(&group->entry);
 	BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
 
 	ret = ida_simple_get(&iommu_group_ida, 0, 0, GFP_KERNEL);