mei: mei_write: revamp function flow

Use goto statement for error handling instead of deeper if constructs
and rename label 'unlock_dev' to more appropriate 'err'

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index ed4943f..7a03d77 100644 (file)
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -543,24 +543,24 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
 
        if (dev->dev_state != MEI_DEV_ENABLED) {
                rets = -ENODEV;
-               goto unlock_dev;
+               goto err;
        }
 
        i = mei_me_cl_by_id(dev, cl->me_client_id);
        if (i < 0) {
                rets = -ENODEV;
-               goto unlock_dev;
+               goto err;
        }
        if (length > dev->me_clients[i].props.max_msg_length || length <= 0) {
                rets = -EMSGSIZE;
-               goto unlock_dev;
+               goto err;
        }
 
        if (cl->state != MEI_FILE_CONNECTED) {
                rets = -ENODEV;
                dev_err(&dev->pdev->dev, "host client = %d,  is not connected to ME client = %d",
                        cl->host_client_id, cl->me_client_id);
-               goto unlock_dev;
+               goto err;
        }
        if (cl == &dev->iamthif_cl) {
                write_cb = find_amthi_read_list_entry(dev, file);
@@ -599,17 +599,17 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
        if (!write_cb) {
                dev_err(&dev->pdev->dev, "write cb allocation failed\n");
                rets = -ENOMEM;
-               goto unlock_dev;
+               goto err;
        }
        rets = mei_io_cb_alloc_req_buf(write_cb, length);
        if (rets)
-               goto unlock_dev;
+               goto err;
 
        dev_dbg(&dev->pdev->dev, "cb request size = %zd\n", length);
 
        rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
        if (rets)
-               goto unlock_dev;
+               goto err;
 
        cl->sm_state = 0;
        if (length == 4 &&
@@ -624,7 +624,7 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
        if (cl == &dev->iamthif_cl) {
                rets = mei_io_cb_alloc_resp_buf(write_cb, dev->iamthif_mtu);
                if (rets)
-                       goto unlock_dev;
+                       goto err;
 
                write_cb->major_file_operations = MEI_IOCTL;
 
@@ -641,7 +641,7 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
                        if (rets) {
                                dev_err(&dev->pdev->dev, "amthi write failed with status = %d\n",
                                    rets);
-                               goto unlock_dev;
+                               goto err;
                        }
                }
                mutex_unlock(&dev->device_lock);
@@ -654,51 +654,51 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
            cl->host_client_id, cl->me_client_id);
        rets = mei_flow_ctrl_creds(dev, cl);
        if (rets < 0)
-               goto unlock_dev;
+               goto err;
 
-       if (rets && dev->mei_host_buffer_is_empty) {
-               rets = 0;
-               dev->mei_host_buffer_is_empty = false;
-               if (length >  mei_hbuf_max_data(dev)) {
-                       mei_hdr.length = mei_hbuf_max_data(dev);
-                       mei_hdr.msg_complete = 0;
-               } else {
-                       mei_hdr.length = length;
-                       mei_hdr.msg_complete = 1;
-               }
-               mei_hdr.host_addr = cl->host_client_id;
-               mei_hdr.me_addr = cl->me_client_id;
-               mei_hdr.reserved = 0;
-               dev_dbg(&dev->pdev->dev, "call mei_write_message header=%08x.\n",
-                   *((u32 *) &mei_hdr));
-               if (mei_write_message(dev, &mei_hdr,
-                       (unsigned char *) (write_cb->request_buffer.data),
-                       mei_hdr.length)) {
-                       rets = -ENODEV;
-                       goto unlock_dev;
-               }
+       if (rets == 0 || dev->mei_host_buffer_is_empty == false) {
+               write_cb->buf_idx = 0;
+               mei_hdr.msg_complete = 0;
                cl->writing_state = MEI_WRITING;
-               write_cb->buf_idx = mei_hdr.length;
-               if (mei_hdr.msg_complete) {
-                       if (mei_flow_ctrl_reduce(dev, cl)) {
-                               rets = -ENODEV;
-                               goto unlock_dev;
-                       }
-                       list_add_tail(&write_cb->list, &dev->write_waiting_list.list);
-               } else {
-                       list_add_tail(&write_cb->list, &dev->write_list.list);
-               }
+               goto out;
+       }
 
+       dev->mei_host_buffer_is_empty = false;
+       if (length >  mei_hbuf_max_data(dev)) {
+               mei_hdr.length = mei_hbuf_max_data(dev);
+               mei_hdr.msg_complete = 0;
        } else {
+               mei_hdr.length = length;
+               mei_hdr.msg_complete = 1;
+       }
+       mei_hdr.host_addr = cl->host_client_id;
+       mei_hdr.me_addr = cl->me_client_id;
+       mei_hdr.reserved = 0;
+       dev_dbg(&dev->pdev->dev, "call mei_write_message header=%08x.\n",
+           *((u32 *) &mei_hdr));
+       if (mei_write_message(dev, &mei_hdr,
+               write_cb->request_buffer.data, mei_hdr.length)) {
+               rets = -ENODEV;
+               goto err;
+       }
+       cl->writing_state = MEI_WRITING;
+       write_cb->buf_idx = mei_hdr.length;
 
-               write_cb->buf_idx = 0;
-               cl->writing_state = MEI_WRITING;
+out:
+       if (mei_hdr.msg_complete) {
+               if (mei_flow_ctrl_reduce(dev, cl)) {
+                       rets = -ENODEV;
+                       goto err;
+               }
+               list_add_tail(&write_cb->list, &dev->write_waiting_list.list);
+       } else {
                list_add_tail(&write_cb->list, &dev->write_list.list);
        }
+
        mutex_unlock(&dev->device_lock);
        return length;
 
-unlock_dev:
+err:
        mutex_unlock(&dev->device_lock);
        mei_io_cb_free(write_cb);
        return rets;