From 94fcca9f8999e7828d5f4dc181daa39cad2af38a Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zheng.yan@oracle.com>
Date: Fri, 9 Oct 2009 09:25:16 -0400
Subject: [PATCH] Btrfs: optimize back reference update during
 btrfs_drop_snapshot

This patch reading level 0 tree blocks that already use full backrefs.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---
Reading git-format-patch failed