[pve-devel] [PATCH storage] fix volume activation for ZFS subvols

[Fabian Ebner <f.ebner@proxmox.com>]

When using the path to request properties, and no ZFS file system is mounted
at that path, ZFS will fall back to the parent filesystem:

> # zfs unmount myzpool/subvol-172-disk-0
> # zfs get mounted /myzpool/subvol-172-disk-0
> NAME     PROPERTY  VALUE    SOURCE
> myzpool  mounted   yes      -
> # zfs get mounted myzpool/subvol-172-disk-0
> NAME                       PROPERTY  VALUE    SOURCE
> myzpool/subvol-172-disk-0  mounted   no       -

Thus, we cannot use the path and need to use the dataset directly.

Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
---

See commit 59fdc2b71e5da8eaf3c821a5c55f410f58da200a for more context.
I did build the package as root to run the zfs regressiontests this time.

 PVE/Storage/ZFSPoolPlugin.pm | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
index 07540b3..2f0a80a 100644
--- a/PVE/Storage/ZFSPoolPlugin.pm
+++ b/PVE/Storage/ZFSPoolPlugin.pm
@@ -549,15 +549,14 @@ sub activate_volume {
 
     return 1 if defined($snapname);
 
-    my (undef, undef, undef, undef, undef, undef, $format) = $class->parse_volname($volname);
+    my (undef, $dataset, undef, undef, undef, undef, $format) = $class->parse_volname($volname);
 
     if ($format eq 'raw') {
 	$class->zfs_wait_for_zvol_link($scfg, $volname);
     } elsif ($format eq 'subvol') {
-	my ($path, undef, undef) = $class->path($scfg, $volname, $storeid);
-	my $mounted = $class->zfs_get_properties($scfg, 'mounted', "$path");
+	my $mounted = $class->zfs_get_properties($scfg, 'mounted', "$scfg->{pool}/$dataset");
 	if ($mounted !~ m/^yes$/) {
-	    $class->zfs_request($scfg, undef, 'mount', "$path");
+	    $class->zfs_request($scfg, undef, 'mount', "$scfg->{pool}/$dataset");
 	}
     }
 
-- 
2.20.1