diff --git a/btrbk b/btrbk
index a03aa4c..f2bced2 100755
--- a/btrbk
+++ b/btrbk
@@ -3445,7 +3445,7 @@ sub get_related_snapshots($$;$)
   my $svol = shift // die;
   my $btrbk_basename = shift; # if set, also filter by direct_leaf
   my @ret = map( { vinfo_resolved($_, $snaproot, btrbk_direct_leaf => $btrbk_basename) // () }
-                 @{get_related_nodes($svol, readonly => 1, omit_self => 1)} );
+                 @{_related_nodes($svol->{node}, readonly => 1, omit_self => 1)} );
 
   if($do_trace) { TRACE "get_related_snapshots: found: $_->{PRINT}" foreach(@ret); }
   DEBUG "Found " . scalar(@ret) . " related snapshots of \"$svol->{PRINT}\" in: $snaproot->{PRINT}" . (defined($btrbk_basename) ? "/$btrbk_basename.*" : "");
@@ -3455,26 +3455,26 @@ sub get_related_snapshots($$;$)
 
 sub _correlated_nodes($$)
 {
-  my $droot = shift || die;
-  my $src_vol = shift || die;
+  my $dnode = shift || die; # any node on target filesystem
+  my $snode = shift || die;
   my @ret;
 
-  if($src_vol->{node}{is_root}) {
-    DEBUG "Skip search for correlated targets: source subvolume is btrfs root: $src_vol->{PRINT}";
+  if($snode->{is_root}) {
+    TRACE "Skip search for correlated targets: source subvolume is btrfs root: " . _fs_path($snode) if($do_trace);
     return @ret;
   }
-  unless($src_vol->{node}{readonly}) {
-    DEBUG "Skip search for correlated targets: source subvolume is not read-only: $src_vol->{PRINT}";
+  unless($snode->{readonly}) {
+    TRACE "Skip search for correlated targets: source subvolume is not read-only: " . _fs_path($snode) if($do_trace);
     return @ret;
   }
 
   # find matches by comparing uuid / received_uuid
-  my $uuid = $src_vol->{node}{uuid};
-  my $received_uuid = $src_vol->{node}{received_uuid};
+  my $uuid = $snode->{uuid};
+  my $received_uuid = $snode->{received_uuid};
   $received_uuid = undef if($received_uuid eq '-');
 
-  my $received_uuid_hash = $droot->{node}{TREE_ROOT}{RECEIVED_UUID_HASH};
-  my $uuid_hash = $droot->{node}{TREE_ROOT}{UUID_HASH};
+  my $received_uuid_hash = $dnode->{TREE_ROOT}{RECEIVED_UUID_HASH};
+  my $uuid_hash = $dnode->{TREE_ROOT}{UUID_HASH};
 
   # match uuid/received_uuid combinations
   my @match;
@@ -3485,7 +3485,7 @@ sub _correlated_nodes($$)
   }
 
   @ret = grep($_->{readonly}, @match);
-  TRACE "correlated_nodes: droot=\"$droot->{PRINT}/\", src_vol=\"$src_vol->{PRINT}\": [" . join(", ", map _fs_path($_),@ret) . "]" if($do_trace);
+  TRACE "correlated_nodes: dst=\"" . _fs_path($dnode) . "\", src=\"" . _fs_path($snode) . "\": [" . join(", ", map _fs_path($_),@ret) . "]" if($do_trace);
   return @ret;
 }
 
@@ -3498,7 +3498,7 @@ sub get_receive_targets($$;@)
   my %opts = @_;
   my @ret;
 
-  my @correlated = _correlated_nodes($droot, $src_vol);
+  my @correlated = _correlated_nodes($droot->{node}, $src_vol->{node});
   foreach (@correlated) {
     my $vinfo = vinfo_resolved($_, $droot); # returns undef if not below $droot
     if(exists($_->{BTRBK_RAW})) {
@@ -3532,7 +3532,7 @@ sub get_best_correlated($$;@)
   my %opts = @_;
   my $inaccessible_nodes = $opts{push_inaccessible_nodes};
 
-  my @correlated = _correlated_nodes($droot, $src_vol); # all matching src_vol, from droot->TREE_ROOT
+  my @correlated = _correlated_nodes($droot->{node}, $src_vol->{node}); # all matching src_vol, from droot->TREE_ROOT
   foreach (@correlated) {
     my $vinfo = vinfo_resolved($_, $droot); # $vinfo is within $droot
     return [ $src_vol, $vinfo ] if($vinfo);
@@ -3549,17 +3549,17 @@ sub get_best_correlated($$;@)
 
 
 # returns all related readonly nodes (by parent_uuid relationship), unsorted.
-sub get_related_nodes($;@)
+sub _related_nodes($;@)
 {
-  my $vol = shift // die;
+  my $snode = shift // die;
   my %opts = @_;
-  TRACE "related_nodes: resolving related subvolumes of: $vol->{PATH}" if($do_trace);
+  TRACE "related_nodes: resolving related subvolumes of: " . _fs_path($snode) if($do_trace);
 
   # iterate parent chain
   my @related_nodes;
-  my $uuid_hash = $vol->{node}{TREE_ROOT}{UUID_HASH};
-  my $parent_uuid_hash = $vol->{node}{TREE_ROOT}{PARENT_UUID_HASH};
-  my $node = $vol->{node};
+  my $uuid_hash = $snode->{TREE_ROOT}{UUID_HASH};
+  my $parent_uuid_hash = $snode->{TREE_ROOT}{PARENT_UUID_HASH};
+  my $node = $snode;
   my $uuid = $node->{uuid};
   my $abort_distance = 4096;
 
@@ -3572,7 +3572,7 @@ sub get_related_nodes($;@)
     $distance++;
   }
   if($distance >= $abort_distance) {
-    my $logmsg = "Parent UUID chain exceeds depth=$abort_distance, ignoring related parents of uuid=$uuid for: $vol->{PATH}";
+    my $logmsg = "Parent UUID chain exceeds depth=$abort_distance, ignoring related parents of uuid=$uuid for: " . _fs_path($snode);
     DEBUG $logmsg;
     WARN_ONCE $logmsg unless($opts{nowarn});
   }
@@ -3587,7 +3587,7 @@ sub get_related_nodes($;@)
     my $children = $parent_uuid_hash->{$uuid};
     if($children) {
       if($distance >= $abort_distance) {
-        my $logmsg = "Parent/child relations exceed depth=$abort_distance, ignoring related children of uuid=$uuid for: $vol->{PATH}";
+        my $logmsg = "Parent/child relations exceed depth=$abort_distance, ignoring related children of uuid=$uuid for: " . _fs_path($snode);
         DEBUG $logmsg;
         WARN_ONCE $logmsg unless($opts{nowarn});
       } else {
@@ -3621,8 +3621,8 @@ sub get_related_nodes($;@)
   }
 
   if($opts{omit_self}) {
-    my $vol_node_id = $vol->{node}{id};
-    my @filtered = grep { $_->{id} != $vol_node_id } @related_nodes;
+    my $snode_id = $snode->{id};
+    my @filtered = grep { $_->{id} != $snode_id } @related_nodes;
     TRACE "related_nodes: found total=" . scalar(@filtered) . " related readonly subvolumes" if($do_trace);
     return \@filtered;
   }
@@ -3671,7 +3671,7 @@ sub get_best_parent($$$;@)
   # improvements, as this only affects extra clones.
   my %c_rel_id;   # map id to c_related
   my @c_related;  # candidates for parent (correlated + related), unsorted
-  foreach (@{get_related_nodes($svol, readonly => 1, omit_self => 1, nowarn => 1)}) {
+  foreach (@{_related_nodes($svol->{node}, readonly => 1, omit_self => 1, nowarn => 1)}) {
     my $vinfo = vinfo_resolved($_, $resolve_sroot);
     if((not $vinfo) && $source_fallback_all_mountpoints) { # related node is not under $resolve_sroot
       $vinfo = vinfo_resolved_all_mountpoints($_, $svol);
@@ -3691,7 +3691,7 @@ sub get_best_parent($$$;@)
   my @c_related_newer = sort { ($a->[0]{node}{cgen} - $cgen_ref) <=> ($b->[0]{node}{cgen} - $cgen_ref) }
                         grep { $_->[0]{node}{cgen} >  $cgen_ref } @c_related;
 
-  # NOTE: While get_related_nodes() returns deep parent_uuid
+  # NOTE: While _related_nodes() returns deep parent_uuid
   # relations, there is always a chance that these relations get
   # broken.
   #
@@ -5755,7 +5755,7 @@ MAIN:
       foreach my $svol (@subvol_args) {
         my $svol_gen = $svol->{node}{readonly} ? $svol->{node}{cgen} : $svol->{node}{gen};
         my @related = map({ vinfo_resolved_all_mountpoints($_, $svol->{VINFO_MOUNTPOINT}) // () }
-                          @{get_related_nodes($svol)}); # includes $svol
+                          @{_related_nodes($svol->{node})}); # includes $svol
         push @resolved_vol, @related;
       }
     }