UBI: get device when opening volume

When a volume is opened, get its kref via get_device() call.
And put the reference when closing the volume. With this, we
may have a bit saner volume delete.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 8e15002a36c3..96f5fef5f3fa 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -156,6 +156,7 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
                 vol->exclusive = 1;
                 break;
         }
+        get_device(&vol->dev);
         spin_unlock(&ubi->volumes_lock);
 
         desc->vol = vol;
@@ -274,6 +275,7 @@ void ubi_close_volume(struct ubi_volume_desc *desc)
         spin_unlock(&vol->ubi->volumes_lock);
 
         kfree(desc);
+        put_device(&vol->dev);
         module_put(THIS_MODULE);
 }
 EXPORT_SYMBOL_GPL(ubi_close_volume);