diff --git a/fs/affs/super.c b/fs/affs/super.c
index c6c2a513ec92..c609005a9eaa 100644
--- a/fs/affs/super.c
+++ b/fs/affs/super.c
@@ -389,7 +389,7 @@ static int affs_fill_super(struct super_block *sb, void *data, int silent)
 	 * blocks, we will have to change it.
 	 */
 
-	size = i_size_read(sb->s_bdev->bd_inode) >> 9;
+	size = bdev_nr_sectors(sb->s_bdev);
 	pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size);
 
 	affs_set_blocksize(sb, PAGE_SIZE);