Complete rewrite of virt-df:

[virt-top.git] / virt-df / virt_df_linux_swap.ml

diff --git a/virt-df/virt_df_linux_swap.ml b/virt-df/virt_df_linux_swap.ml
index 7fbad7f..ad56149 100644 (file)
--- a/virt-df/virt_df_linux_swap.ml
+++ b/virt-df/virt_df_linux_swap.ml
@@ -1,23 +1,54 @@
 (* 'df' command for virtual domains.
- *
- * Support for Linux swap partitions.
- *)
-
-(* Int64 operators for convenience. *)
-let (+^) = Int64.add
-let (-^) = Int64.sub
-let ( *^ ) = Int64.mul
-let (/^) = Int64.div
-
-let probe_swap target part_type fd start size =
-  Virt_df.Swap {
-    Virt_df.swap_name = "Linux swap";
-    swap_block_size = 4096L;           (* XXX *)
-    swap_blocks_total = size *^ 512L /^ 4096L;
-  }
+
+   (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 Linux swap partitions.
+*)
+
+open Virt_df_gettext.Gettext
+open Virt_df
+
+let probe_swap (dev : device) =
+  (* Load the "superblock" (ie. first 0x1000 bytes). *)
+  let bits = dev#read_bitstring 0L 0x1000 in
+
+  bitmatch bits with
+    (* Actually this isn't just padding. *)
+  | padding : 8*0x1000 - 10*8 : bitstring;
+    magic : 10*8 : bitstring
+      when Bitmatch.string_of_bitstring magic = "SWAPSPACE2" ->
+    {
+      fs_name = s_ "Linux swap";
+      fs_block_size = 4096L;           (* XXX *)
+      fs_blocks_total = dev#size /^ 4096L;
+
+      (* The remaining fields are ignored when fs_is_swap is true. *)
+      fs_is_swap = true;
+      fs_blocks_reserved = 0L;
+      fs_blocks_avail = 0L;
+      fs_blocks_used = 0L;
+      fs_inodes_total = 0L;
+      fs_inodes_reserved = 0L;
+      fs_inodes_avail = 0L;
+      fs_inodes_used = 0L;
+    }
+  | _ ->
+      raise Not_found                  (* Not Linux swapspace. *)
 
 (* Register with main code. *)
-let () =
-  Virt_df.fs_register
-    [ 0x82 ]                           (* Partition type. *)
-    probe_swap
+let () = filesystem_type_register "linux_swap" probe_swap