(* 'df' command for virtual domains.
- * $Id$
- *
- * Support for LVM2 PVs.
- *)
+
+ (C) Copyright 2007 Richard W.M. Jones, Red Hat Inc.
+ http://libvirt.org/
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ Support for LVM2 PVs.
+*)
open Printf
+open Virt_df_gettext.Gettext
+open Virt_df
-(* Int64 operators for convenience. *)
-let (+^) = Int64.add
-let (-^) = Int64.sub
-let ( *^ ) = Int64.mul
-let (/^) = Int64.div
+let sector_size = 512
+let sector_size64 = 512L
-let probe_lvm2 target part_type fd start size =
- Virt_df.ProbeFailed "LVM2 not supported yet"
+let pv_label_offset = sector_size64
+
+(* Probe to see if it's an LVM2 PV. Look for the "LABELONE" label. *)
+let rec probe_pv dev =
+ try ignore (read_pv_label dev); true
+ with _ -> false
+
+and read_pv_label dev =
+ (* Load the second sector. *)
+ let bits = dev#read_bitstring pv_label_offset sector_size in
+
+ Bitmatch.hexdump_bitstring stdout bits;
+
+ bitmatch bits with
+ | labelone : 8*8 : bitstring; (* "LABELONE" *)
+ padding : 16*8 : bitstring;
+ lvm2_ver : 8*8 : bitstring; (* "LVM2 001" *)
+ uuid : 32*8 : bitstring (* UUID *)
+ when Bitmatch.string_of_bitstring labelone = "LABELONE" &&
+ Bitmatch.string_of_bitstring lvm2_ver = "LVM2 001" ->
+ uuid
+ | _ ->
+ invalid_arg (sprintf "read_pv_label: %s: not an LVM2 physical volume"
+ dev#name)
+
+(* We are passed a list of devices which we previously identified
+ * as PVs belonging to us. From these produce a list of all LVs
+ * (as devices) and return them. Note that we don't try to detect
+ * what is on these LVs - that will be done in the main code.
+ *)
+let list_lvs devs = []
(* Register with main code. *)
let () =
- Virt_df.fs_register
- [ 0x8e ] (* Partition type. *)
- probe_lvm2
+ lvm_type_register "LVM2" probe_pv list_lvs