block: rnbd: add .release to rnbd_dev_ktype

Every ktype must provides a .release function that will be called after
the last kobject_put.

Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: zhuyj

drivers/block/rnbd/rnbd-clt-sysfs.c

@@ -475,9 +475,17 @@ void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev)
 	}
 }
 
+static void rnbd_dev_release(struct kobject *kobj)
+{
+	struct rnbd_clt_dev *dev = container_of(kobj, struct rnbd_clt_dev, kobj);
+
+	kfree(dev);
+}
+
 static const struct kobj_type rnbd_dev_ktype = {
 	.sysfs_ops      = &kobj_sysfs_ops,
 	.default_groups = rnbd_dev_groups,
+	.release	= rnbd_dev_release,
 };
 
 static int rnbd_clt_add_dev_kobj(struct rnbd_clt_dev *dev)

drivers/block/rnbd/rnbd-clt.c

@@ -60,7 +60,9 @@ static void rnbd_clt_put_dev(struct rnbd_clt_dev *dev)
 	kfree(dev->pathname);
 	rnbd_clt_put_sess(dev->sess);
 	mutex_destroy(&dev->lock);
-	kfree(dev);
+
+	if (dev->kobj.state_initialized)
+		kobject_put(&dev->kobj);
 }
 
 static inline bool rnbd_clt_get_dev(struct rnbd_clt_dev *dev)
@@ -1517,7 +1519,7 @@ static bool insert_dev_if_not_exists_devpath(struct rnbd_clt_dev *dev)
 	return found;
 }
 
-static void delete_dev(struct rnbd_clt_dev *dev)
+static void rnbd_delete_dev(struct rnbd_clt_dev *dev)
 {
 	struct rnbd_clt_session *sess = dev->sess;
 
@@ -1638,7 +1640,7 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 	kfree(rsp);
 	rnbd_put_iu(sess, iu);
 del_dev:
-	delete_dev(dev);
+	rnbd_delete_dev(dev);
 put_dev:
 	rnbd_clt_put_dev(dev);
 put_sess:
@@ -1647,13 +1649,13 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 	return ERR_PTR(ret);
 }
 
-static void destroy_gen_disk(struct rnbd_clt_dev *dev)
+static void rnbd_destroy_gen_disk(struct rnbd_clt_dev *dev)
 {
 	del_gendisk(dev->gd);
 	put_disk(dev->gd);
 }
 
-static void destroy_sysfs(struct rnbd_clt_dev *dev,
+static void rnbd_destroy_sysfs(struct rnbd_clt_dev *dev,
 			  const struct attribute *sysfs_self)
 {
 	rnbd_clt_remove_dev_symlink(dev);
@@ -1691,9 +1693,9 @@ int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 	dev->dev_state = DEV_STATE_UNMAPPED;
 	mutex_unlock(&dev->lock);
 
-	delete_dev(dev);
-	destroy_sysfs(dev, sysfs_self);
-	destroy_gen_disk(dev);
+	rnbd_delete_dev(dev);
+	rnbd_destroy_sysfs(dev, sysfs_self);
+	rnbd_destroy_gen_disk(dev);
 	if (was_mapped && sess->rtrs)
 		send_msg_close(dev, dev->device_id, RTRS_PERMIT_WAIT);