From 0dff4725df2174ed2715d05793b40663a981633d Mon Sep 17 00:00:00 2001
From: John Snow <jsnow@redhat.com>
Date: Wed, 18 Jul 2018 22:54:53 +0200
Subject: [PATCH 68/89] block/backup: disable copy offloading for backup

RH-Author: John Snow <jsnow@redhat.com>
Message-id: <20180718225511.14878-18-jsnow@redhat.com>
Patchwork-id: 81417
O-Subject: [RHEL-7.6 qemu-kvm-rhev PATCH 17/35] block/backup: disable copy offloading for backup
Bugzilla: 1207657
RH-Acked-by: Eric Blake <eblake@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Fam Zheng <famz@redhat.com>

Downstream only for 2.12.0; there are several upstream fixes that fix
the copy_range support for block/backup that are in 3.0 that we're not
prepared to backport to 2.12.0.

For now, then, hardcode block/backup to use the old bounce buffer method
that works without additional caveats.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 block/backup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/backup.c b/block/backup.c
index d26eeb5..adb3cbd 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -727,7 +727,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     } else {
         job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
     }
-    job->use_copy_range = true;
+    job->use_copy_range = false;
     job->copy_range_size = MIN_NON_ZERO(blk_get_max_transfer(job->common.blk),
                                         blk_get_max_transfer(job->target));
     job->copy_range_size = MAX(job->cluster_size,
-- 
1.8.3.1