qeth: synchronize configuration interface

Synchronize access to the drivers configuration interface.
Also do not allow configuration changes during online/offline
transition.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index 904b1f3567b..b447e1998c6 100644
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -924,6 +924,7 @@ static int __qeth_l2_set_online(struct ccwgroup_device *gdev, int recovery_mode)
         enum qeth_card_states recover_flag;
 
         BUG_ON(!card);
+        mutex_lock(&card->conf_mutex);
         QETH_DBF_TEXT(SETUP, 2, "setonlin");
         QETH_DBF_HEX(SETUP, 2, &card, sizeof(void *));
 
@@ -956,7 +957,7 @@ static int __qeth_l2_set_online(struct ccwgroup_device *gdev, int recovery_mode)
                         dev_warn(&card->gdev->dev,
                                 "The LAN is offline\n");
                         card->lan_online = 0;
-                        return 0;
+                        goto out;
                 }
                 rc = -ENODEV;
                 goto out_remove;
@@ -995,6 +996,8 @@ static int __qeth_l2_set_online(struct ccwgroup_device *gdev, int recovery_mode)
         }
         /* let user_space know that device is online */
         kobject_uevent(&gdev->dev.kobj, KOBJ_CHANGE);
+out:
+        mutex_unlock(&card->conf_mutex);
         return 0;
 
 out_remove:
@@ -1007,6 +1010,7 @@ out_remove:
                 card->state = CARD_STATE_RECOVER;
         else
                 card->state = CARD_STATE_DOWN;
+        mutex_unlock(&card->conf_mutex);
         return rc;
 }
 
@@ -1022,6 +1026,7 @@ static int __qeth_l2_set_offline(struct ccwgroup_device *cgdev,
         int rc = 0, rc2 = 0, rc3 = 0;
         enum qeth_card_states recover_flag;
 
+        mutex_lock(&card->conf_mutex);
         QETH_DBF_TEXT(SETUP, 3, "setoffl");
         QETH_DBF_HEX(SETUP, 3, &card, sizeof(void *));
 
@@ -1040,6 +1045,7 @@ static int __qeth_l2_set_offline(struct ccwgroup_device *cgdev,
                 card->state = CARD_STATE_RECOVER;
         /* let user_space know that device is offline */
         kobject_uevent(&cgdev->dev.kobj, KOBJ_CHANGE);
+        mutex_unlock(&card->conf_mutex);
         return 0;
 }