[06/14] vfio: remove the iommudata hack for noiommu groups

Commit Message

Christoph Hellwig Aug. 24, 2021, 2:46 p.m. UTC

Just pass a noiommu argument to vfio_create_group and set up the
->noiommu flag directly, and remove the now superflous
vfio_iommu_group_put helper.

Signed-off-by: Christoph Hellwig <[e-mail]>
---
 drivers/vfio/vfio.c | 30 +++++++++++-------------------
 1 file changed, 11 insertions(+), 19 deletions(-)

Comments

Jason Gunthorpe Aug. 24, 2021, 11:45 p.m. UTC | #1

On Tue, Aug 24, 2021 at 04:46:41PM +0200, Christoph Hellwig wrote:
> Just pass a noiommu argument to vfio_create_group and set up the
> ->noiommu flag directly, and remove the now superflous
> vfio_iommu_group_put helper.
> 
> Signed-off-by: Christoph Hellwig <[e-mail]>
> ---
>  drivers/vfio/vfio.c | 30 +++++++++++-------------------
>  1 file changed, 11 insertions(+), 19 deletions(-)

I like this a lot better

Reviewed-by: Jason Gunthorpe <[e-mail]>

Jason

Patch

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 53e0d52f3b0209..f44532fed5bb4f 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -169,16 +169,6 @@  static void vfio_release_device_set(struct vfio_device *device)
 	xa_unlock(&vfio_device_set_xa);
 }
 
-static void vfio_iommu_group_put(struct iommu_group *group, struct device *dev)
-{
-#ifdef CONFIG_VFIO_NOIOMMU
-	if (iommu_group_get_iommudata(group) == &noiommu)
-		iommu_group_remove_device(dev);
-#endif
-
-	iommu_group_put(group);
-}
-
 #ifdef CONFIG_VFIO_NOIOMMU
 static void *vfio_noiommu_open(unsigned long arg)
 {
@@ -345,7 +335,8 @@  static void vfio_group_unlock_and_free(struct vfio_group *group)
 /**
  * Group objects - create, release, get, put, search
  */
-static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
+static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group,
+		bool noiommu)
 {
 	struct vfio_group *group, *tmp;
 	struct device *dev;
@@ -364,9 +355,7 @@  static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
 	atomic_set(&group->opened, 0);
 	init_waitqueue_head(&group->container_q);
 	group->iommu_group = iommu_group;
-#ifdef CONFIG_VFIO_NOIOMMU
-	group->noiommu = (iommu_group_get_iommudata(iommu_group) == &noiommu);
-#endif
+	group->noiommu = noiommu;
 	BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
 
 	group->nb.notifier_call = vfio_iommu_group_notifier;
@@ -801,12 +790,11 @@  static struct vfio_group *vfio_noiommu_group_alloc(struct device *dev)
 		return ERR_CAST(iommu_group);
 
 	iommu_group_set_name(iommu_group, "vfio-noiommu");
-	iommu_group_set_iommudata(iommu_group, &noiommu, NULL);
 	ret = iommu_group_add_device(iommu_group, dev);
 	if (ret)
 		goto out_put_group;
 
-	group = vfio_create_group(iommu_group);
+	group = vfio_create_group(iommu_group, true);
 	if (IS_ERR(group)) {
 		ret = PTR_ERR(group);
 		goto out_remove_device;
@@ -853,7 +841,7 @@  static struct vfio_group *vfio_group_find_or_alloc(struct device *dev)
 	 */
 	group = vfio_group_get_from_iommu(iommu_group);
 	if (!group) {
-		group = vfio_create_group(iommu_group);
+		group = vfio_create_group(iommu_group, false);
 		if (!IS_ERR(group))
 			return group;
 	}
@@ -883,7 +871,9 @@  int vfio_register_group_dev(struct vfio_device *device)
 		dev_WARN(device->dev, "Device already exists on group %d\n",
 			 iommu_group_id(group->iommu_group));
 		vfio_device_put(existing_device);
-		vfio_iommu_group_put(group->iommu_group, device->dev);
+		if (group->noiommu)
+			iommu_group_remove_device(device->dev);
+		iommu_group_put(group->iommu_group);
 		return -EBUSY;
 	}
 
@@ -1028,7 +1018,9 @@  void vfio_unregister_group_dev(struct vfio_device *device)
 	if (list_empty(&group->device_list))
 		wait_event(group->container_q, !group->container);
 
-	vfio_iommu_group_put(group->iommu_group, device->dev);
+	if (group->noiommu)
+		iommu_group_remove_device(device->dev);
+	iommu_group_put(group->iommu_group);
 }
 EXPORT_SYMBOL_GPL(vfio_unregister_group_dev);