UBI: introduce volume refcounting

Add ref_count field to UBI volumes and remove weired "vol->removed"
field. This way things are better understandable and we do not have
to do whold show_attr operation under spinlock.

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

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 9c283768319f..780c273ff452 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -152,6 +152,7 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
                 break;
         }
         get_device(&vol->dev);
+        vol->ref_count += 1;
         spin_unlock(&ubi->volumes_lock);
 
         desc->vol = vol;
@@ -261,10 +262,11 @@ void ubi_close_volume(struct ubi_volume_desc *desc)
         case UBI_EXCLUSIVE:
                 vol->exclusive = 0;
         }
+        vol->ref_count -= 1;
         spin_unlock(&vol->ubi->volumes_lock);
 
-        kfree(desc);
         put_device(&vol->dev);
+        kfree(desc);
         module_put(THIS_MODULE);
 }
 EXPORT_SYMBOL_GPL(ubi_close_volume);