PCI interface changes for PCIE-AER enabling

This patch reflects some pci interface changes in pciif.h in XEN head
file. And also add domain shutdown support in xend for shutting domain
from DOM0 kernel when non-recoverable uncorrected pci error happens.

Signed-off-by: Jiang Yunhong <yunhong.jiang@intel.com>
Signed-off-by: Ke Liping <liping.ke@intel.com>

tools/python/xen/xend/server/pciif.py

@@ -35,6 +35,8 @@ import resource
 import re
 
 from xen.xend.server.pciquirk import *
+from xen.xend.xenstore.xstransact import xstransact
+from xen.xend.xenstore.xswatch import xswatch
 
 xc = xen.lowlevel.xc.xc()
 
@@ -58,6 +60,7 @@ def parse_hex(val):
 class PciController(DevController):
 
     def __init__(self, vm):
+        self.aerStateWatch = None
         DevController.__init__(self, vm)
 
 
@@ -431,9 +434,23 @@ class PciController(DevController):
 
         for (domain, bus, slot, func) in pci_dev_list:
             self.setupOneDevice(domain, bus, slot, func)
-
+        wPath = '/local/domain/0/backend/pci/%u/0/aerState' % (self.getDomid())
+        self.aerStatePath = xswatch(wPath, self._handleAerStateWatch)
+        log.debug('pci: register aer watch %s', wPath)
         return
 
+    def _handleAerStateWatch(self, _):
+        log.debug('XendDomainInfo.handleAerStateWatch')
+        if self.getDomid() == 0:
+            raise XendError('Domain 0 cannot be shutdown')
+        readPath = '/local/domain/0/backend/pci/%u/0/aerState' % (self.getDomid())
+        action = xstransact.Read(readPath)
+        if action and action=='aerfail':
+            log.debug('shutdown domain because of aer handle error')
+            self.vm.shutdown('poweroff')
+        return True
+
+
     def cleanupOneDevice(self, domain, bus, slot, func):
         """ Detach I/O resources for device from frontend domain
         """
@@ -545,6 +562,22 @@ class PciController(DevController):
 
         return new_num_devs
 
+    def destroyDevice(self, devid, force):
+        DevController.destroyDevice(self, devid, True)
+        log.debug('pci: unregister aer watch')
+        self.unwatchAerState
+
+    def unwatchAerState(self):
+        """Remove the watch on the domain's aerState node, if any."""
+        try:
+            try:
+                if self.aerStateWatch:
+                    self.aerStateWatch.unwatch()
+            finally:
+                self.aerStateWatch = None
+        except:
+            log.exception("Unwatching aerState failed.")
+  
     def waitForBackend(self,devid):
         return (0, "ok - no hotplug")