Merge "Update tgt iSCSI target on volume extend"

cinder/exception.py

@@ -1154,6 +1154,10 @@ class ISCSITargetDetachFailed(CinderException):
     message = _("Failed to detach iSCSI target for volume %(volume_id)s.")
 
 
+class TargetUpdateFailed(CinderException):
+    message = _("Failed to update target for volume %(volume_id)s.")
+
+
 class ISCSITargetHelperCommandFailed(CinderException):
     message = "%(error_message)s"
 

cinder/volume/drivers/lvm.py

@@ -589,6 +589,11 @@ class LVMVolumeDriver(driver.VolumeDriver):
         """Extend an existing volume's size."""
         self.vg.extend_volume(volume['name'],
                               self._sizestr(new_size))
+        try:
+            self.target_driver.extend_target(volume)
+        except Exception:
+            LOG.exception('Error extending target after volume resize.')
+            raise exception.TargetUpdateFailed(volume_id=volume.id)
 
     def manage_existing(self, volume, existing_ref):
         """Manages an existing LV.

cinder/volume/manager.py

@@ -2591,6 +2591,9 @@ class VolumeManager(manager.CleanableManager,
         self._notify_about_volume_usage(context, volume, "resize.start")
         try:
             self.driver.extend_volume(volume, new_size)
+        except exception.TargetUpdateFailed:
+            # We just want to log this but continue on with quota commit
+            LOG.warning('Volume extended but failed to update target.')
         except Exception:
             LOG.exception("Extend volume failed.",
                           resource=volume)

cinder/volume/targets/iscsi.py

@@ -327,6 +327,17 @@ class ISCSITarget(driver.Target):
         except exception.NotFound:
             LOG.debug('Failed to get CHAP auth from DB for %s.', volume['id'])
 
+    def extend_target(self, volume):
+        """Reinitializes a target after the LV has been extended.
+
+        Note: This will cause IO disruption in most cases.
+        """
+        iscsi_name = "%s%s" % (self.configuration.target_prefix,
+                               volume['name'])
+
+        if volume.volume_attachment:
+            self._do_tgt_update(iscsi_name, force=True)
+
     @abc.abstractmethod
     def _get_target_and_lun(self, context, volume):
         """Get iscsi target and lun."""
@@ -349,6 +360,9 @@ class ISCSITarget(driver.Target):
     def _get_target(self, iqn):
         pass
 
+    def _do_tgt_update(self, name, force=False):
+        pass
+
 
 class SanISCSITarget(ISCSITarget):
     """iSCSI target for san devices.

cinder/volume/targets/tgt.py

@@ -111,9 +111,13 @@ class TgtAdm(iscsi.ISCSITarget):
         return iscsi_target, lun
 
     @utils.retry(putils.ProcessExecutionError)
-    def _do_tgt_update(self, name):
-        (out, err) = utils.execute('tgt-admin', '--update', name,
-                                   run_as_root=True)
+    def _do_tgt_update(self, name, force=False):
+        args = ['tgt-admin', '--update', name]
+        if force:
+            # Note: force may fail if there is active IO, but retry decorator
+            # should allow it to succeed on second attempt
+            args.append('-f')
+        (out, err) = utils.execute(*args, run_as_root=True)
         LOG.debug("StdOut from tgt-admin --update: %s", out)
         LOG.debug("StdErr from tgt-admin --update: %s", err)