New console transport and update xenconsoled.

Add a new console interface using a seperate shared page and event channel
instead of passing the console input/output over control messages.
Update xenconsoled to use the new console interface.
Make xenconsoled garbage collect dying domains by subscribing to
the domain exception virq.
Signed-off-by: Robert Read <robert@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>

tools/python/xen/lowlevel/xc/xc.c

@@ -268,25 +268,33 @@ static PyObject *pyxc_linux_build(PyObject *self,
     u32 dom;
     char *image, *ramdisk = NULL, *cmdline = "";
     int flags = 0, vcpus = 1;
-    int control_evtchn, store_evtchn;
+    int control_evtchn, store_evtchn, console_evtchn;
     unsigned long store_mfn = 0;
+    unsigned long console_mfn = 0;
 
     static char *kwd_list[] = { "dom", "control_evtchn", "store_evtchn", 
-                                "image", "ramdisk", "cmdline", "flags",
+                                "console_evtchn", "image", 
+				/* optional */
+				"ramdisk", "cmdline", "flags",
 				"vcpus", NULL };
 
-    if ( !PyArg_ParseTupleAndKeywords(args, kwds, "iiis|ssii", kwd_list,
+    if ( !PyArg_ParseTupleAndKeywords(args, kwds, "iiiis|ssii", kwd_list,
                                       &dom, &control_evtchn, &store_evtchn,
-                                      &image, &ramdisk, &cmdline, &flags,
+				      &console_evtchn, &image, 
+				      /* optional */
+				      &ramdisk, &cmdline, &flags,
                                       &vcpus) )
         return NULL;
 
     if ( xc_linux_build(xc->xc_handle, dom, image,
                         ramdisk, cmdline, control_evtchn, flags, vcpus,
-                        store_evtchn, &store_mfn) != 0 )
+                        store_evtchn, &store_mfn, 
+			console_evtchn, &console_mfn) != 0 )
         return PyErr_SetFromErrno(xc_error);
     
-    return Py_BuildValue("{s:i}", "store_mfn", store_mfn);
+    return Py_BuildValue("{s:i,s:i}", 
+			 "store_mfn", store_mfn,
+			 "console_mfn", console_mfn);
 }
 
 static PyObject *pyxc_vmx_build(PyObject *self,

tools/python/xen/xend/XendDomainInfo.py

@@ -47,7 +47,7 @@ from xen.xend.XendError import XendError, VmError
 from xen.xend.XendRoot import get_component
 
 from xen.xend.uuid import getUuid
-from xen.xend.xenstore import DBVar
+from xen.xend.xenstore import DBVar, XenNode, DBMap
 
 """Shutdown code for poweroff."""
 DOMAIN_POWEROFF = 0
@@ -231,6 +231,7 @@ class XendDomainInfo:
         DBVar('start_time',    ty='float'),
         DBVar('state',         ty='str'),
         DBVar('store_mfn',     ty='long'),
+        DBVar('console_mfn',     ty='long'),
         DBVar('restart_mode',  ty='str'),
         DBVar('restart_state', ty='str'),
         DBVar('restart_time',  ty='float'),
@@ -260,6 +261,8 @@ class XendDomainInfo:
         self.channel = None
         self.store_channel = None
         self.store_mfn = None
+        self.console_channel = None
+        self.console_mfn = None
         self.controllers = {}
         
         self.info = None
@@ -297,6 +300,9 @@ class XendDomainInfo:
         if self.store_channel:
             self.store_channel.saveToDB(self.db.addChild("store_channel"),
                                         save=save)
+        if self.console_channel:
+            self.console_channel.saveToDB(self.db.addChild("console_channel"),
+                                        save=save)
         if self.image:
             self.image.exportToDB(save=save, sync=sync)
         self.db.exportToDB(self, fields=self.__exports__, save=save, sync=sync)
@@ -329,6 +335,9 @@ class XendDomainInfo:
     def getStoreChannel(self):
         return self.store_channel
 
+    def getConsoleChannel(self):
+        return self.console_channel
+
     def update(self, info):
         """Update with  info from xc.domain_getinfo().
         """
@@ -518,6 +527,14 @@ class XendDomainInfo:
             sxpr.append(self.store_channel.sxpr())
         if self.store_mfn:
             sxpr.append(['store_mfn', self.store_mfn])
+        if self.console_channel:
+            sxpr.append(['console_channel', self.console_channel.sxpr()])
+        if self.console_mfn:
+            sxpr.append(['console_mfn', self.console_mfn])
+# already in (devices)
+#        console = self.getConsole()
+#        if console:
+#            sxpr.append(console.sxpr())
 
         if self.restart_count:
             sxpr.append(['restart_count', self.restart_count])
@@ -712,6 +729,13 @@ class XendDomainInfo:
             except Exception, ex:
                 log.warning("error in domain release on xenstore: %s", ex)
                 pass
+        if self.console_channel:
+            # notify processes using this cosole?
+            try:
+                self.console_channel.close()
+                self.console_channel = None
+            except:
+                pass
         if self.image:
             try:
                 self.device_model_pid = 0
@@ -808,6 +832,7 @@ class XendDomainInfo:
         """
         self.channel = self.openChannel("channel", 0, 1)
         self.store_channel = self.eventChannel("store_channel")
+        self.console_channel = self.eventChannel("console_channel")
 
     def create_configured_devices(self):
         devices = sxp.children(self.config, 'device')
@@ -1003,6 +1028,7 @@ class XendDomainInfo:
         self.configure_fields()
         self.create_devices()
         self.create_blkif()
+        self.publish_console()
 
     def create_blkif(self):
         """Create the block device interface (blkif) for the vm.
@@ -1017,6 +1043,12 @@ class XendDomainInfo:
             backend = blkif.getBackend(0)
             backend.connect(recreate=self.recreate)
 
+    def publish_console(self):
+        db = DBMap(db=XenNode("/console/%d" % self.id))
+        db.clear()
+        db['domain'] = self.db.getPath()
+        db.saveDB(save=True)
+        
     def configure_fields(self):
         """Process the vm configuration fields using the registered handlers.
         """

tools/python/xen/xend/image.py

@@ -238,16 +238,33 @@ class LinuxImageHandler(ImageHandler):
             store_evtchn = self.vm.store_channel.port2
         else:
             store_evtchn = 0
+        if self.vm.console_channel:
+            console_evtchn = self.vm.console_channel.port2
+        else:
+            console_evtchn = 0
+
+        log.debug("dom            = %d", self.vm.getDomain())
+        log.debug("image          = %s", self.kernel)
+        log.debug("control_evtchn = %s", self.vm.channel.getRemotePort())
+        log.debug("store_evtchn   = %d", store_evtchn)
+        log.debug("console_evtchn = %d", console_evtchn)
+        log.debug("cmdline        = %s", self.cmdline)
+        log.debug("ramdisk        = %s", self.ramdisk)
+        log.debug("flags          = %d", self.flags)
+        log.debug("vcpus          = %d", self.vm.vcpus)
+
         ret = xc.linux_build(dom            = self.vm.getDomain(),
                              image          = self.kernel,
                              control_evtchn = self.vm.channel.getRemotePort(),
                              store_evtchn   = store_evtchn,
+                             console_evtchn = console_evtchn,
                              cmdline        = self.cmdline,
                              ramdisk        = self.ramdisk,
                              flags          = self.flags,
                              vcpus          = self.vm.vcpus)
         if isinstance(ret, dict):
             self.vm.store_mfn = ret.get('store_mfn')
+            self.vm.console_mfn = ret.get('console_mfn')
             return 0
         return ret