mei: add mei_cl_alloc_linked function

Add convenient wrapper mei_cl_alloc_linked
to simplify error handling
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/client.c

@@ -547,11 +547,11 @@ struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
  * mei_cl_link - allocate host id in the host map
  *
  * @cl: host client
- * @id: fixed host id or -1 for generic one
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
  *
  * Return: 0 on success
  *	-EINVAL on incorrect values
- *	-ENONET if client not found
+ *	-EMFILE if open count exceeded.
  */
 int mei_cl_link(struct mei_cl *cl, int id)
 {
@@ -869,6 +869,37 @@ int mei_cl_connect(struct mei_cl *cl, struct file *file)
 	return rets;
 }
 
+/**
+ * mei_cl_alloc_linked - allocate and link host client
+ *
+ * @dev: the device structure
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
+ *
+ * Return: cl on success ERR_PTR on failure
+ */
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id)
+{
+	struct mei_cl *cl;
+	int ret;
+
+	cl = mei_cl_allocate(dev);
+	if (!cl) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ret = mei_cl_link(cl, id);
+	if (ret)
+		goto err;
+
+	return cl;
+err:
+	kfree(cl);
+	return ERR_PTR(ret);
+}
+
+
+
 /**
  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
  *

drivers/misc/mei/client.h

@@ -75,6 +75,8 @@ void mei_cl_init(struct mei_cl *cl, struct mei_device *dev);
 int mei_cl_link(struct mei_cl *cl, int id);
 int mei_cl_unlink(struct mei_cl *cl);
 
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id);
+
 int mei_cl_flush_queues(struct mei_cl *cl);
 struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl);
 

drivers/misc/mei/main.c

@@ -59,24 +59,18 @@ static int mei_open(struct inode *inode, struct file *file)
 
 	mutex_lock(&dev->device_lock);
 
-	cl = NULL;
-
-	err = -ENODEV;
 	if (dev->dev_state != MEI_DEV_ENABLED) {
 		dev_dbg(dev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
 		    mei_dev_state_str(dev->dev_state));
+		err = -ENODEV;
 		goto err_unlock;
 	}
 
-	err = -ENOMEM;
-	cl = mei_cl_allocate(dev);
-	if (!cl)
-		goto err_unlock;
-
-	/* open_handle_count check is handled in the mei_cl_link */
-	err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-	if (err)
+	cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl)) {
+		err = PTR_ERR(cl);
 		goto err_unlock;
+	}
 
 	file->private_data = cl;
 
@@ -86,7 +80,6 @@ static int mei_open(struct inode *inode, struct file *file)
 
 err_unlock:
 	mutex_unlock(&dev->device_lock);
-	kfree(cl);
 	return err;
 }
 

drivers/misc/mei/nfc.c

@@ -482,8 +482,8 @@ static void mei_nfc_init(struct work_struct *work)
 int mei_nfc_host_init(struct mei_device *dev)
 {
 	struct mei_nfc_dev *ndev;
-	struct mei_cl *cl_info, *cl = NULL;
-	struct mei_me_client *me_cl;
+	struct mei_cl *cl_info, *cl;
+	struct mei_me_client *me_cl = NULL;
 	int ret;
 
 
@@ -500,17 +500,6 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
-	ndev->cl_info = mei_cl_allocate(dev);
-	ndev->cl = mei_cl_allocate(dev);
-
-	cl = ndev->cl;
-	cl_info = ndev->cl_info;
-
-	if (!cl || !cl_info) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
 	/* check for valid client id */
 	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_info_guid);
 	if (!me_cl) {
@@ -519,17 +508,21 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
+	cl_info = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl_info)) {
+		ret = PTR_ERR(cl_info);
+		goto err;
+	}
+
 	cl_info->me_client_id = me_cl->client_id;
 	cl_info->cl_uuid = me_cl->props.protocol_name;
 	mei_me_cl_put(me_cl);
-
-	ret = mei_cl_link(cl_info, MEI_HOST_CLIENT_ID_ANY);
-	if (ret)
-		goto err;
-
+	me_cl = NULL;
 
 	list_add_tail(&cl_info->device_link, &dev->device_list);
 
+	ndev->cl_info = cl_info;
+
 	/* check for valid client id */
 	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
 	if (!me_cl) {
@@ -538,16 +531,21 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
+	cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl)) {
+		ret = PTR_ERR(cl);
+		goto err;
+	}
+
 	cl->me_client_id = me_cl->client_id;
 	cl->cl_uuid = me_cl->props.protocol_name;
 	mei_me_cl_put(me_cl);
-
-	ret = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-	if (ret)
-		goto err;
+	me_cl = NULL;
 
 	list_add_tail(&cl->device_link, &dev->device_list);
 
+	ndev->cl = cl;
+
 	ndev->req_id = 1;
 
 	INIT_WORK(&ndev->init_work, mei_nfc_init);
@@ -557,6 +555,7 @@ int mei_nfc_host_init(struct mei_device *dev)
 	return 0;
 
 err:
+	mei_me_cl_put(me_cl);
 	mei_nfc_free(ndev);
 
 	return ret;