From 0e43734d4c46e156785bb1d2acc5b3c10b7d5dd5 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Thu, 21 Feb 2019 08:37:42 -0500 Subject: media: v4l2-subdev: add release() internal op If the subdevice created a device node, then the v4l2_subdev cannot be freed until the last user of the device node closes it. This means that we need a release() callback in v4l2_subdev_internal_ops that is called from the video_device release function so the subdevice driver can postpone freeing memory until the that callback is called. If no video device node was created then the release callback can be called immediately when the subdev is unregistered. Signed-off-by: Hans Verkuil Reviewed-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-device.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'drivers/media/v4l2-core') diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c index e0ddb9a52bd1..7cca0de1b730 100644 --- a/drivers/media/v4l2-core/v4l2-device.c +++ b/drivers/media/v4l2-core/v4l2-device.c @@ -216,10 +216,18 @@ error_module: } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); +static void v4l2_subdev_release(struct v4l2_subdev *sd) +{ + struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL; + + if (sd->internal_ops && sd->internal_ops->release) + sd->internal_ops->release(sd); + module_put(owner); +} + static void v4l2_device_release_subdev_node(struct video_device *vdev) { - struct v4l2_subdev *sd = video_get_drvdata(vdev); - sd->devnode = NULL; + v4l2_subdev_release(video_get_drvdata(vdev)); kfree(vdev); } @@ -318,8 +326,9 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) media_device_unregister_entity(&sd->entity); } #endif - video_unregister_device(sd->devnode); - if (!sd->owner_v4l2_dev) - module_put(sd->owner); + if (sd->devnode) + video_unregister_device(sd->devnode); + else + v4l2_subdev_release(sd); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); -- cgit v1.2.3