ctcm rollback in case of errors

Group device now cleanly reacts to failures during channel start and
implements a clean rollback.

Signed-off-by: Einar Lueck <elelueck@de.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/ctcm_main.c b/drivers/s390/net/ctcm_main.c
index c5b83874500ccb9b9154195f405e7c57178daff3..db054ed1a8cc7fae08e2a45a8108434406cbefcc 100644 (file)
--- a/drivers/s390/net/ctcm_main.c
+++ b/drivers/s390/net/ctcm_main.c
@@ -1530,11 +1530,16 @@ static int ctcm_new_device(struct ccwgroup_device *cgdev)
        struct net_device *dev;
        struct ccw_device *cdev0;
        struct ccw_device *cdev1;
+       struct channel *readc;
+       struct channel *writec;
        int ret;
+       int result;
 
        priv = dev_get_drvdata(&cgdev->dev);
-       if (!priv)
-               return -ENODEV;
+       if (!priv) {
+               result = -ENODEV;
+               goto out_err_result;
+       }
 
        cdev0 = cgdev->cdev[0];
        cdev1 = cgdev->cdev[1];
@@ -1545,31 +1550,40 @@ static int ctcm_new_device(struct ccwgroup_device *cgdev)
        snprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
 
        ret = add_channel(cdev0, type, priv);
-       if (ret)
-               return ret;
+       if (ret) {
+               result = ret;
+               goto out_err_result;
+       }
        ret = add_channel(cdev1, type, priv);
-       if (ret)
-               return ret;
+       if (ret) {
+               result = ret;
+               goto out_remove_channel1;
+       }
 
        ret = ccw_device_set_online(cdev0);
        if (ret != 0) {
-               /* may be ok to fail now - can be done later */
                CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
                        "%s(%s) set_online rc=%d",
                                CTCM_FUNTAIL, read_id, ret);
+               result = -EIO;
+               goto out_remove_channel2;
        }
 
        ret = ccw_device_set_online(cdev1);
        if (ret != 0) {
-               /* may be ok to fail now - can be done later */
                CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
                        "%s(%s) set_online rc=%d",
                                CTCM_FUNTAIL, write_id, ret);
+
+               result = -EIO;
+               goto out_ccw1;
        }
 
        dev = ctcm_init_netdevice(priv);
-       if (dev == NULL)
-                       goto out;
+       if (dev == NULL) {
+               result = -ENODEV;
+               goto out_ccw2;
+       }
 
        for (direction = READ; direction <= WRITE; direction++) {
                priv->channel[direction] =
@@ -1587,12 +1601,14 @@ static int ctcm_new_device(struct ccwgroup_device *cgdev)
        /* sysfs magic */
        SET_NETDEV_DEV(dev, &cgdev->dev);
 
-       if (register_netdev(dev))
-                       goto out_dev;
+       if (register_netdev(dev)) {
+               result = -ENODEV;
+               goto out_dev;
+       }
 
        if (ctcm_add_attributes(&cgdev->dev)) {
-               unregister_netdev(dev);
-                       goto out_dev;
+               result = -ENODEV;
+               goto out_unregister;
        }
 
        strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
@@ -1608,13 +1624,22 @@ static int ctcm_new_device(struct ccwgroup_device *cgdev)
                        priv->channel[WRITE]->id, priv->protocol);
 
        return 0;
+out_unregister:
+       unregister_netdev(dev);
 out_dev:
        ctcm_free_netdevice(dev);
-out:
+out_ccw2:
        ccw_device_set_offline(cgdev->cdev[1]);
+out_ccw1:
        ccw_device_set_offline(cgdev->cdev[0]);
-
-       return -ENODEV;
+out_remove_channel2:
+       readc = channel_get(type, read_id, READ);
+       channel_remove(readc);
+out_remove_channel1:
+       writec = channel_get(type, write_id, WRITE);
+       channel_remove(writec);
+out_err_result:
+       return result;
 }
 
 /**