Add VDI chain cleanup script.

References bug 949477

Change-Id: I819d4ed56675a4ef4e46adca2978b433386e128d

1 files changed, 128 insertions, 0 deletions

diff --git a/tools/xenserver/vdi_chain_cleanup.py b/tools/xenserver/vdi_chain_cleanup.py
new file mode 100644
index 0000000000..4d4892d8be
--- /dev/null
+++ b/tools/xenserver/vdi_chain_cleanup.py
@@ -0,0 +1,128 @@
+#!/usr/bin/env python
+
+# Copyright 2012 OpenStack, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+This script is designed to cleanup any VHDs (and their descendents) which have
+a bad parent pointer.
+
+The script needs to be run in the dom0 of the affected host.
+
+The available actions are:
+
+    - print: display the filenames of the affected VHDs
+    - delete: remove the affected VHDs
+    - move: move the affected VHDs out of the SR into another directory
+"""
+import glob
+import os
+import subprocess
+import sys
+
+
+class ExecutionFailed(Exception):
+    def __init__(self, returncode, stdout, stderr, max_stream_length=32):
+        self.returncode = returncode
+        self.stdout = stdout[:max_stream_length]
+        self.stderr = stderr[:max_stream_length]
+        self.max_stream_length = max_stream_length
+
+    def __repr__(self):
+        return "<ExecutionFailed returncode=%s out='%s' stderr='%s'>" % (
+            self.returncode, self.stdout, self.stderr)
+
+    __str__ = __repr__
+
+
+def execute(cmd, ok_exit_codes=None):
+    if ok_exit_codes is None:
+        ok_exit_codes = [0]
+
+    proc = subprocess.Popen(
+        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+
+    (stdout, stderr) = proc.communicate()
+
+    if proc.returncode not in ok_exit_codes:
+        raise ExecutionFailed(proc.returncode, stdout, stderr)
+
+    return proc.returncode, stdout, stderr
+
+
+def usage():
+    print "usage: %s <SR PATH> <print|delete|move>" % sys.argv[0]
+    sys.exit(1)
+
+
+def main():
+    if len(sys.argv) < 3:
+        usage()
+
+    sr_path = sys.argv[1]
+    action = sys.argv[2]
+
+    if action not in ('print', 'delete', 'move'):
+        usage()
+
+    if action == 'move':
+        if len(sys.argv) < 4:
+            print "error: must specify where to move bad VHDs"
+            sys.exit(1)
+
+        bad_vhd_path = sys.argv[3]
+        if not os.path.exists(bad_vhd_path):
+            os.makedirs(bad_vhd_path)
+
+    bad_leaves = []
+    descendents = {}
+
+    for fname in glob.glob(os.path.join(sr_path, "*.vhd")):
+        (returncode, stdout, stderr) = execute(
+            ['vhd-util', 'query', '-n', fname, '-p'], ok_exit_codes=[0, 22])
+
+        stdout = stdout.strip()
+
+        if  stdout.endswith('.vhd'):
+            try:
+                descendents[stdout].append(fname)
+            except KeyError:
+                descendents[stdout] = [fname]
+        elif 'query failed' in stdout:
+            bad_leaves.append(fname)
+
+    def walk_vhds(root):
+        yield root
+        if root in descendents:
+            for child in descendents[root]:
+                for vhd in walk_vhds(child):
+                    yield vhd
+
+    for bad_leaf in bad_leaves:
+        for bad_vhd in walk_vhds(bad_leaf):
+            print bad_vhd
+            if action == "print":
+                pass
+            elif action == "delete":
+                os.unlink(bad_vhd)
+            elif action == "move":
+                new_path = os.path.join(bad_vhd_path,
+                                        os.path.basename(bad_vhd))
+                os.rename(bad_vhd, new_path)
+            else:
+                raise Exception("invalid action %s" % action)
+
+
+if __name__ == '__main__':
+    main()