diff options
Diffstat (limited to 'tools/python/xen/xend/server/channel.py')
| -rwxr-xr-x | tools/python/xen/xend/server/channel.py | 181 |
1 files changed, 146 insertions, 35 deletions
diff --git a/tools/python/xen/xend/server/channel.py b/tools/python/xen/xend/server/channel.py index e2b2043e66..00f451a7b8 100755 --- a/tools/python/xen/xend/server/channel.py +++ b/tools/python/xen/xend/server/channel.py @@ -14,52 +14,129 @@ DEBUG = 0 RESPONSE_TIMEOUT = 20.0 -def eventChannel(dom1, dom2): - """Create an event channel between domains. - The returned dict contains dom1, dom2, port1 and port2 on success. +class EventChannel(dict): + """An event channel between domains. + """ + + def interdomain(cls, dom1, dom2, port1=0, port2=0): + """Create an event channel between domains. + + @return EventChannel (None on error) + """ + v = xc.evtchn_bind_interdomain(dom1=dom1, dom2=dom2, + port1=port1, port2=port2) + if v: + v = cls(dom1, dom2, v) + return v + + interdomain = classmethod(interdomain) + + def restoreFromDB(cls, db, dom1, dom2, port1=0, port2=0): + """Create an event channel using db info if available. + Inverse to saveToDB(). + + @param db db + @param dom1 + @param dom2 + @param port1 + @param port2 + """ + try: + dom1 = int(db['dom1']) + except: pass + try: + dom2 = int(db['dom2']) + except: pass + try: + port1 = int(db['port1']) + except: pass + try: + port2 = int(db['port2']) + except: pass + evtchn = cls.interdomain(dom1, dom2, port1=port1, port2=port2) + return evtchn + + restoreFromDB = classmethod(restoreFromDB) + + def __init__(self, dom1, dom2, d): + d['dom1'] = dom1 + d['dom2'] = dom2 + self.update(d) + self.dom1 = dom1 + self.dom2 = dom2 + self.port1 = d.get('port1') + self.port2 = d.get('port2') + + def close(self): + """Close the event channel. + """ + def evtchn_close(dom, port): + try: + xc.evtchn_close(dom=dom, port=port) + except Exception, ex: + pass + + if DEBUG: + print 'EventChannel>close>', self + evtchn_close(self.dom1, self.port1) + evtchn_close(self.dom2, self.port2) + + def saveToDB(self, db): + """Save the event channel to the db so it can be restored later, + using restoreFromDB() on the class. + + @param db db + """ + db['dom1'] = str(self.dom1) + db['dom2'] = str(self.dom2) + db['port1'] = str(self.port1) + db['port2'] = str(self.port2) + db.saveDB() + + def sxpr(self): + return ['event-channel', + ['dom1', self.dom1 ], + ['port1', self.port1 ], + ['dom2', self.dom2 ], + ['port2', self.port2 ] + ] + + def __repr__(self): + return ("<EventChannel dom1:%d:%d dom2:%d:%d>" + % (self.dom1, self.port1, self.dom2, self.port2)) - @return dict (empty on error) +def eventChannel(dom1, dom2, port1=0, port2=0): + """Create an event channel between domains. + + @return EventChannel (None on error) """ - evtchn = xc.evtchn_bind_interdomain(dom1=dom1, dom2=dom2) - if evtchn: - evtchn['dom1'] = dom1 - evtchn['dom2'] = dom2 - return evtchn + return EventChannel.interdomain(dom1, dom2, port1=port1, port2=port2) def eventChannelClose(evtchn): - """Close an event channel that was opened by eventChannel(). + """Close an event channel. """ - def evtchn_close(dom, port): - if (dom is None) or (port is None): return - try: - xc.evtchn_close(dom=dom, port=port) - except Exception, ex: - pass - if not evtchn: return - if DEBUG: - print 'eventChannelClose>', evtchn - evtchn_close(evtchn.get('dom1'), evtchn.get('port1')) - evtchn_close(evtchn.get('dom2'), evtchn.get('port2')) - + evtchn.close() class ChannelFactory: - """Factory for creating channels. + """Factory for creating control channels. Maintains a table of channels. """ """ Channels indexed by index. """ - channels = {} + channels = None thread = None notifier = None """Map of ports to the virq they signal.""" - virqPorts = {} + virqPorts = None def __init__(self): """Constructor - do not use. Use the channelFactory function.""" + self.channels = {} + self.virqPorts = {} self.notifier = xu.notifier() # Register interest in virqs. self.bind_virq(xen.lowlevel.xc.VIRQ_DOM_EXC) @@ -70,10 +147,6 @@ class ChannelFactory: self.virqPorts[port] = virq log.info("Virq %s on port %s", virq, port) - def virq(self): - log.error("virq") - self.notifier.virq_send(self.virqPort) - def start(self): """Fork a thread to read messages. """ @@ -182,9 +255,13 @@ class ChannelFactory: return None def openChannel(self, dom, local_port=0, remote_port=0): - return (self.findChannel(dom, local_port=local_port, remote_port=remote_port) - or - self.newChannel(dom, local_port, remote_port)) + chan = self.findChannel(dom, local_port=local_port, + remote_port=remote_port) + if chan: + return chan + chan = self.newChannel(dom, local_port, remote_port) + return chan + def createPort(self, dom, local_port=0, remote_port=0): """Create a port for a channel to the given domain. @@ -203,8 +280,31 @@ class ChannelFactory: @type remote: int @return: port object """ - return xu.port(dom, local_port=int(local_port), - remote_port=int(remote_port)) + return xu.port(dom, local_port=local_port, remote_port=remote_port) + + def restoreFromDB(self, db, dom, local, remote): + """Create a channel using ports restored from the db (if available). + Otherwise use the given ports. This is the inverse operation to + saveToDB() on a channel. + + @param db db + @param dom domain the channel connects to + @param local default local port + @param remote default remote port + """ + try: + local_port = int(db['local_port']) + except: + local_port = local + try: + remote_port = int(db['remote_port']) + except: + remote_port = remote + try: + chan = self.openChannel(dom, local_port, remote_port) + except: + return None + return chan def channelFactory(): """Singleton constructor for the channel factory. @@ -218,7 +318,7 @@ def channelFactory(): return inst class Channel: - """Chanel to a domain. + """Control channel to a domain. Maintains a list of device handlers to dispatch requests to, based on the request type. """ @@ -239,6 +339,17 @@ class Channel: # Make sure the port will deliver all the messages. self.port.register(TYPE_WILDCARD) + def saveToDB(self, db): + """Save the channel ports to the db so the channel can be restored later, + using restoreFromDB() on the factory. + + @param db db + """ + if self.closed: return + db['local_port'] = str(self.getLocalPort()) + db['remote_port'] = str(self.getRemotePort()) + db.saveDB() + def getKey(self): """Get the channel key. """ |