[PATCH] new bd_mutex lockdep annotation

Use the gendisk partition number to set a lock class. Signed-off-by: Peter Zijlstra <[email protected]> Cc: Neil Brown <[email protected]> Cc: Ingo Molnar <[email protected]> Acked-by: Arjan van de Ven <[email protected]> Cc: Jason Baron <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
maraz · Dec 8, 2006 · 35a6027 · 35a6027
1 parent 2e7b651
commit 35a6027
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/fs/block_dev.c b/fs/block_dev.c
@@ -355,10 +355,14 @@ static int bdev_set(struct inode *inode, void *data)
 
 static LIST_HEAD(all_bdevs);
 
+static struct lock_class_key bdev_part_lock_key;
+
 struct block_device *bdget(dev_t dev)
 {
 	struct block_device *bdev;
 	struct inode *inode;
+	struct gendisk *disk;
+	int part = 0;
 
 	inode = iget5_locked(bd_mnt->mnt_sb, hash(dev),
 			bdev_test, bdev_set, &dev);
@@ -384,6 +388,11 @@ struct block_device *bdget(dev_t dev)
 		list_add(&bdev->bd_list, &all_bdevs);
 		spin_unlock(&bdev_lock);
 		unlock_new_inode(inode);
+		mutex_init(&bdev->bd_mutex);
+		disk = get_gendisk(dev, &part);
+		if (part)
+			lockdep_set_class(&bdev->bd_mutex, &bdev_part_lock_key);
+		put_disk(disk);
 	}
 	return bdev;
 }