From 70b27f364315e4ad4cb77cdebe530e5bdbdf3dcb Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Fri, 17 Feb 2017 10:58:25 +0100
Subject: [PATCH] qcow2: Use BB for resizing in qcow2_amend_options()

In order to able to convert bdrv_truncate() to take a BdrvChild and
later to correctly check the resize permission here, we need to use a
BlockBackend for resizing the image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/qcow2.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/qcow2.c b/block/qcow2.c
index 3e274bd1ba48..254545a83bdd 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -3250,7 +3250,11 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,
     }
 
     if (new_size) {
-        ret = bdrv_truncate(bs, new_size);
+        BlockBackend *blk = blk_new();
+        blk_insert_bs(blk, bs);
+        ret = blk_truncate(blk, new_size);
+        blk_unref(blk);
+
         if (ret < 0) {
             return ret;
         }