[HVM] Save/restore: tidy PFN handling in the tools.

Make the differences clearer between the number of frames, the max PFN
and the size of the pfn array, and handle te framebuffer more cleanly.
Signed-off-by: Tim Deegan <Tim.Deegan@xensource.com>

tools/python/xen/xend/XendCheckpoint.py

@@ -74,9 +74,13 @@ def save(fd, dominfo, network, live, dst, checkpoint=False):
 
         image_cfg = dominfo.info.get('image', {})
         hvm = image_cfg.has_key('hvm')
+        stdvga = 0
 
         if hvm:
             log.info("save hvm domain")
+            if image_cfg['hvm']['devices']['stdvga'] == 1:
+                stdvga = 1
+
         # xc_save takes three customization parameters: maxit, max_f, and
         # flags the last controls whether or not save is 'live', while the
         # first two further customize behaviour when 'live' save is
@@ -84,7 +88,8 @@ def save(fd, dominfo, network, live, dst, checkpoint=False):
         # libxenguest; see the comments and/or code in xc_linux_save() for
         # more information.
         cmd = [xen.util.auxbin.pathTo(XC_SAVE), str(fd),
-               str(dominfo.getDomid()), "0", "0", str(int(live) | (int(hvm) << 2)) ]
+               str(dominfo.getDomid()), "0", "0", 
+               str(int(live) | (int(hvm) << 2) | (int(stdvga) << 3)) ]
         log.debug("[xc_save]: %s", string.join(cmd))
 
         def saveInputHandler(line, tochild):