[pve-devel] [PATCH_V2] Storage: add method

[Wolfgang Link]

add method volume_rollback_is_possible and redactor
Improve error handling
If snapshot is not reversible catch it before vm will lock and shutdown.
This is the case if zfs has an younger snapshot.

Signed-off-by: Wolfgang Link <w.link at proxmox.com>
---
 PVE/Storage.pm               |   15 +++++++++++++++
 PVE/Storage/Plugin.pm        |    6 ++++++
 PVE/Storage/ZFSPlugin.pm     |    7 ++-----
 PVE/Storage/ZFSPoolPlugin.pm |   12 ++++++++++--
 4 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/PVE/Storage.pm b/PVE/Storage.pm
index 8711710..7845ad1 100755
--- a/PVE/Storage.pm
+++ b/PVE/Storage.pm
@@ -144,6 +144,21 @@ sub volume_resize {
     }
 }
 
+sub volume_rollback_is_possible {
+    my ($cfg, $volid, $snap) = @_;
+    
+    my ($storeid, $volname) = parse_volume_id($volid, 1);
+    if ($storeid) {
+        my $scfg = storage_config($cfg, $storeid);
+        my $plugin = PVE::Storage::Plugin->lookup($scfg->{type});
+        return $plugin->volume_rollback_is_possible($scfg, $storeid, $volname, $snap);
+    } elsif ($volid =~ m|^(/.+)$| && -e $volid) {
+        die "snapshot rollback device $volid is not possible";
+    } else {
+        die "can't parse volume id";
+    }
+}
+
 sub volume_snapshot {
     my ($cfg, $volid, $snap, $running) = @_;
 
diff --git a/PVE/Storage/Plugin.pm b/PVE/Storage/Plugin.pm
index 15c23d4..3eb99f2 100644
--- a/PVE/Storage/Plugin.pm
+++ b/PVE/Storage/Plugin.pm
@@ -656,6 +656,12 @@ sub volume_snapshot {
     return undef;
 }
 
+sub volume_rollback_is_possible {
+    my ($class, $scfg, $storeid, $volname, $snap) = @_; 
+
+    return 1; 
+}
+
 sub volume_snapshot_rollback {
     my ($class, $scfg, $storeid, $volname, $snap) = @_;
 
diff --git a/PVE/Storage/ZFSPlugin.pm b/PVE/Storage/ZFSPlugin.pm
index 77394b9..6aac58d 100644
--- a/PVE/Storage/ZFSPlugin.pm
+++ b/PVE/Storage/ZFSPlugin.pm
@@ -311,11 +311,8 @@ sub volume_snapshot_rollback {
     my ($class, $scfg, $storeid, $volname, $snap) = @_;
 
     # abort rollback if snapshot is not the latest
-    my $recentsnap = $class->zfs_get_latest_snapshot($scfg, $volname);
-    if ($snap ne $recentsnap) {
-        die "cannot rollback, more recent snapshots exist\n";
-    }
-
+    $class->volume_rollback_is_possible($scfg, $storeid, $volname, $snap);
+    
     $class->zfs_delete_lu($scfg, $volname);
 
     $class->zfs_request($class, $scfg, undef, 'rollback', "$scfg->{pool}/$volname\@$snap");
diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
index 754f29f..2a1cfef 100644
--- a/PVE/Storage/ZFSPoolPlugin.pm
+++ b/PVE/Storage/ZFSPoolPlugin.pm
@@ -412,12 +412,20 @@ sub volume_snapshot_rollback {
     my ($class, $scfg, $storeid, $volname, $snap) = @_;
 
     # abort rollback if snapshot is not the latest
+    $class->volume_rollback_is_possible($scfg, $storeid, $volname, $snap);
+
+    zfs_request($class, $scfg, undef, 'rollback', "$scfg->{pool}/$volname\@$snap");
+}
+
+sub volume_rollback_is_possible {
+    my ($class, $scfg, $storeid, $volname, $snap) = @_; 
+    
     my $recentsnap = $class->zfs_get_latest_snapshot($scfg, $volname);
     if ($snap ne $recentsnap) {
-        die "cannot rollback, more recent snapshots exist\n";
+	die "can't rollback, more recent snapshots exist\n";
     }
 
-    zfs_request($class, $scfg, undef, 'rollback', "$scfg->{pool}/$volname\@$snap");
+    return 1; 
 }
 
 sub activate_storage {
-- 
1.7.10.4