config: add overrides for default directory locations

Allowing overrides for the default directory locations seems to
integrate rather well into the existing system. Custom locations
are specified using the "dirs" parameter as a comma-separated list
of "vtype:/location" values.

For now, the option has been enabled for the Directory, CIFS and NFS
backends.

Signed-off-by: Leo Nunner <l.nunner@proxmox.com>

PVE/Storage/CIFSPlugin.pm

@@ -128,6 +128,7 @@ sub properties {
 sub options {
     return {
 	path => { fixed => 1 },
+	dirs => { optional => 1 },
 	server => { fixed => 1 },
 	share => { fixed => 1 },
 	nodes => { optional => 1 },

PVE/Storage/DirPlugin.pm

@@ -54,6 +54,7 @@ sub properties {
 sub options {
     return {
 	path => { fixed => 1 },
+	dirs => { optional => 1 },
 	nodes => { optional => 1 },
 	shared => { optional => 1 },
 	disable => { optional => 1 },

PVE/Storage/NFSPlugin.pm

@@ -79,6 +79,7 @@ sub properties {
 sub options {
     return {
 	path => { fixed => 1 },
+	dirs => { optional => 1 },
 	server => { fixed => 1 },
 	export => { fixed => 1 },
 	nodes => { optional => 1 },

PVE/Storage/Plugin.pm

@@ -181,6 +181,11 @@ my $defaultData = {
 	    default => 'metadata',
 	    optional => 1,
 	},
+	dirs => {
+	    description => "Overrides for default directories",
+	    type => "string", format => "pve-dir-override-list",
+	    optional => 1,
+	},
     },
 };
 
@@ -205,6 +210,12 @@ sub valid_content_types {
     return $def->{content}->[0];
 }
 
+sub dirs_hash_to_string {
+    my $hash = shift;
+
+    return join(',', map { "$_:$hash->{$_}" } sort keys %$hash);
+}
+
 sub default_format {
     my ($scfg) = @_;
 
@@ -335,6 +346,18 @@ sub parse_volume_id {
     die "unable to parse volume ID '$volid'\n";
 }
 
+PVE::JSONSchema::register_format('pve-dir-override', \&verify_dir_override);
+sub verify_dir_override {
+    my ($value, $noerr) = @_;
+
+    if($value =~ m/^([a-z]+):(.+)$/ &&
+	verify_content($1, $noerr) && verify_path($2, $noerr)) {
+	return $value;
+    }
+
+    return undef if $noerr;
+    die "invalid override '$value'\n";
+}
 
 sub private {
     return $defaultData;
@@ -405,6 +428,22 @@ sub decode_value {
 	#    die "storage '$storeid' does not allow node restrictions\n";
 	#}
 
+	return $res;
+    } elsif ($key eq 'dirs') {
+	my $valid_content = $def->{content}->[0];
+	my $res = {};
+
+	foreach my $dir (PVE::Tools::split_list($value)) {
+	    my ($content, $path) = split(/:/, $dir, 2);
+
+	    if (!$valid_content->{$content}) {
+		warn "storage does not support content type '$content'\n";
+		next;
+	    }
+
+	    $res->{$content} = $path;
+	}
+
 	return $res;
     }
 
@@ -419,6 +458,9 @@ sub encode_value {
     } elsif ($key eq 'content') {
 	my $res = content_hash_to_string($value) || 'none';
 	return $res;
+    } elsif ($key eq 'dirs') {
+	my $res = dirs_hash_to_string($value);
+	return $res;
     }
 
     return $value;
@@ -610,12 +652,11 @@ sub get_subdir {
     my $path = $scfg->{path};
 
     die "storage definition has no path\n" if !$path;
+    die "unknown vtype '$vtype'\n" if !exists($vtype_subdirs->{$vtype});
 
-    my $subdir = $vtype_subdirs->{$vtype};
+    my $subdir = $scfg->{dirs}->{$vtype} // "/".$vtype_subdirs->{$vtype};
 
-    die "unknown vtype '$vtype'\n" if !defined($subdir);
-
-    return "$path/$subdir";
+    return $path.$subdir;
 }
 
 sub filesystem_path {

test/get_subdir_test.pm

@@ -27,6 +27,13 @@ foreach my $type (keys %$vtype_subdirs) {
     push @$tests, [ $scfg_with_path, $type, $path ];
 }
 
+# creates additional tests for overrides
+foreach my $type (keys %$vtype_subdirs) {
+    my $override = "/${type}_override";
+    my $scfg_with_override = { path => '/some/path', dirs => { $type => $override } };
+    push @$tests, [ $scfg_with_override, $type, "$scfg_with_override->{path}$scfg_with_override->{dirs}->{$type}" ];
+}
+
 plan tests => scalar @$tests;
 
 foreach my $tt (@$tests) {