From ab3516a6d7bce0cf7d269576ac496ecb73b1f005 Mon Sep 17 00:00:00 2001
From: Fabian Ebner <f.ebner@proxmox.com>
Date: Thu, 5 Aug 2021 10:33:43 +0200
Subject: [PATCH] zfs: fix unmount request

by not dying when the dataset is already unmounted. Can be triggered
for a container by doing two rollbacks in a row.

Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
---
 PVE/Storage/ZFSPoolPlugin.pm | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
index c4be70f..660b3d9 100644
--- a/PVE/Storage/ZFSPoolPlugin.pm
+++ b/PVE/Storage/ZFSPoolPlugin.pm
@@ -477,7 +477,10 @@ sub volume_snapshot_rollback {
     # caches, they get mounted in activate volume again
     # see zfs bug #10931 https://github.com/openzfs/zfs/issues/10931
     if ($format eq 'subvol') {
-	$class->zfs_request($scfg, undef, 'unmount', "$scfg->{pool}/$vname");
+	eval { $class->zfs_request($scfg, undef, 'unmount', "$scfg->{pool}/$vname"); };
+	if (my $err = $@) {
+	    die $err if $err !~ m/not currently mounted$/;
+	}
     }
 
     return $msg;