xend: Remember bootable flag for vbds in xenstore

diff -r a00eb6595d3c tools/python/xen/xend/XendConfig.py
@@ -1285,7 +1289,6 @@ class XendConfig(dict):
                     pass
 
             if dev_type == 'vbd':
-                dev_info['bootable'] = 0
                 if dev_info.get('dev', '').startswith('ioemu:'):
                     dev_info['driver'] = 'ioemu'
                 else:

@@ -1321,7 +1324,7 @@ class XendConfig(dict):
                 if param not in target:
                     target[param] = []
                 if dev_uuid not in target[param]:
-                    if dev_type == 'vbd':
+                    if dev_type == 'vbd' and 'bootable' not in dev_info:
                         # Compat hack -- mark first disk bootable
                         dev_info['bootable'] = int(not target[param])
                     target[param].append(dev_uuid)

@@ -1329,8 +1332,9 @@ class XendConfig(dict):
                 if 'vbd_refs' not in target:
                     target['vbd_refs'] = []
                 if dev_uuid not in target['vbd_refs']:
-                    # Compat hack -- mark first disk bootable
-                    dev_info['bootable'] = int(not target['vbd_refs'])
+                    if 'bootable' not in dev_info:
+                        # Compat hack -- mark first disk bootable
+                        dev_info['bootable'] = int(not target['vbd_refs'])
                     target['vbd_refs'].append(dev_uuid)
                     
             elif dev_type == 'vfb':

diff -r a00eb6595d3c tools/python/xen/xend/server/blkif.py
@@ -78,6 +78,10 @@ class BlkifController(DevController):
         if uuid:
             back['uuid'] = uuid
 
+        bootable = config.get('bootable', None)
+        if bootable != None:
+            back['bootable'] = str(bootable)
+
         if security.on() == xsconstants.XS_POLICY_USE:
             self.do_access_control(config, uname)
 

@@ -143,11 +147,12 @@ class BlkifController(DevController):
         config = DevController.getDeviceConfiguration(self, devid, transaction)
         if transaction is None:
             devinfo = self.readBackend(devid, 'dev', 'type', 'params', 'mode',
-                                       'uuid')
+                                       'uuid', 'bootable')
         else:
             devinfo = self.readBackendTxn(transaction, devid,
-                                          'dev', 'type', 'params', 'mode', 'uuid')
-        dev, typ, params, mode, uuid = devinfo
+                                          'dev', 'type', 'params', 'mode', 'uuid',
+                                          'bootable')
+        dev, typ, params, mode, uuid, bootable = devinfo
         
         if dev:
             if transaction is None:

@@ -165,6 +170,8 @@ class BlkifController(DevController):
             config['mode'] = mode
         if uuid:
             config['uuid'] = uuid
+        if bootable != None:
+            config['bootable'] = int(bootable)
 
         proto = self.readFrontend(devid, 'protocol')
         if proto: