From b4015b7dba40190b0d974e79f04ce3b8d0b7803d Mon Sep 17 00:00:00 2001
From: Neal Gompa <ngompa@fedoraproject.org>
Date: Thu, 15 Jul 2021 05:26:39 -0400
Subject: [PATCH] Force the filesystem to sync to disk before trimming

This ensures that data discard works properly.

Fixes: bc7e8ce561c2b1ec5536bd7a3e77226dbeab538d

Signed-off-by: Neal Gompa <ngompa@fedoraproject.org>
---
 fedora-cloud-base.ks | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fedora-cloud-base.ks b/fedora-cloud-base.ks
index 6ff9c89..74c3d94 100644
--- a/fedora-cloud-base.ks
+++ b/fedora-cloud-base.ks
@@ -124,8 +124,11 @@ rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-$releasever-$basearch
 echo "Zeroing out empty space."
 # This forces the filesystem to reclaim space from deleted files
 dd bs=1M if=/dev/zero of=/var/tmp/zeros || :
-rm -f /var/tmp/zeros
 echo "(Don't worry -- that out-of-space error was expected.)"
+# Force sync to disk (Cf. https://pagure.io/cloud-sig/issue/340#comment-743430)
+btrfs filesystem sync /
+rm -f /var/tmp/zeros
+btrfs filesystem sync /
 
 # When we build the image a networking config file gets left behind.
 # Let's clean it up.