UBI: get device when opening volume

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=450f872a8e1763c883c9f723e6937b7ed223e6d3
Commit:     450f872a8e1763c883c9f723e6937b7ed223e6d3
Parent:     c63a491d3737aec3c47c5e785d87021752ad9fa6
Author:     Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
AuthorDate: Mon Dec 17 13:09:09 2007 +0200
Committer:  Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
CommitDate: Wed Dec 26 19:15:15 2007 +0200

    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 at nokia.com>
---
 drivers/mtd/ubi/cdev.c |    9 ++++++---
 drivers/mtd/ubi/kapi.c |    2 ++
 drivers/mtd/ubi/vmt.c  |    5 -----
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index 24344ba..35d34b6 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -635,9 +635,12 @@ static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
 		}
 
 		err = ubi_remove_volume(desc);
-		if (err)
-			ubi_close_volume(desc);
-
+		/*
+		 * The volume is deleted, and the 'struct ubi_volume' object
+		 * will be freed when 'ubi_close_volume()' will call
+		 * 'put_device()'.
+		 */
+		ubi_close_volume(desc);
 		break;
 	}
 
diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 8e15002..96f5fef 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);
diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c
index ec2dd3c..9dd3689 100644
--- a/drivers/mtd/ubi/vmt.c
+++ b/drivers/mtd/ubi/vmt.c
@@ -435,7 +435,6 @@ int ubi_remove_volume(struct ubi_volume_desc *desc)
 	vol->eba_tbl = NULL;
 	cdev_del(&vol->cdev);
 	volume_sysfs_close(vol);
-	kfree(desc);
 
 	spin_lock(&ubi->volumes_lock);
 	ubi->rsvd_pebs -= reserved_pebs;
@@ -453,10 +452,6 @@ int ubi_remove_volume(struct ubi_volume_desc *desc)
 	spin_unlock(&ubi->volumes_lock);
 
 	paranoid_check_volumes(ubi);
-	mutex_unlock(&ubi->volumes_mutex);
-	module_put(THIS_MODULE);
-	return 0;
-
 out:
 	mutex_unlock(&ubi->volumes_mutex);
 	return err;