From patchwork Thu Jul 26 12:24:17 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 173409 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 971D32C0091 for ; Thu, 26 Jul 2012 22:24:50 +1000 (EST) Received: from localhost ([::1]:54381 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SuN7Y-000750-Dc for incoming@patchwork.ozlabs.org; Thu, 26 Jul 2012 08:24:48 -0400 Received: from eggs.gnu.org ([208.118.235.92]:58166) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SuN7M-00073r-A2 for qemu-devel@nongnu.org; Thu, 26 Jul 2012 08:24:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SuN7B-0006ES-Q9 for qemu-devel@nongnu.org; Thu, 26 Jul 2012 08:24:36 -0400 Received: from e06smtp13.uk.ibm.com ([195.75.94.109]:59801) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SuN7B-0006E2-Ep for qemu-devel@nongnu.org; Thu, 26 Jul 2012 08:24:25 -0400 Received: from /spool/local by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 26 Jul 2012 13:24:22 +0100 Received: from d06nrmr1407.portsmouth.uk.ibm.com (9.149.38.185) by e06smtp13.uk.ibm.com (192.168.101.143) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Thu, 26 Jul 2012 13:24:20 +0100 Received: from d06av11.portsmouth.uk.ibm.com (d06av11.portsmouth.uk.ibm.com [9.149.37.252]) by d06nrmr1407.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q6QCOJHe2990332 for ; Thu, 26 Jul 2012 13:24:19 +0100 Received: from d06av11.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av11.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q6QCOJZ0030401 for ; Thu, 26 Jul 2012 06:24:19 -0600 Received: from localhost (stefanha-thinkpad.manchester-maybrook.uk.ibm.com [9.174.219.145]) by d06av11.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q6QCOI1I030398; Thu, 26 Jul 2012 06:24:19 -0600 From: Stefan Hajnoczi To: Date: Thu, 26 Jul 2012 13:24:17 +0100 Message-Id: <1343305457-17446-1-git-send-email-stefanha@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.10.4 x-cbid: 12072612-2966-0000-0000-000004D5621A X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 195.75.94.109 Cc: Kevin Wolf , Stefan Hajnoczi Subject: [Qemu-devel] [PATCH v3] qemu-iotests: add qed.py image manipulation utility X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The qed.py utility can inspect and manipulate QED image files. It can be used for testing to see the state of image metadata and also to inject corruptions into the image file. It also has a scrubbing feature to copy just the metadata out of an image file, allowing users to share broken image files without revealing data in bug reports. This has lived in my local repo for a long time but could be useful to others. Signed-off-by: Stefan Hajnoczi --- v3: * Replace random duplicate choice loop with straight-line code [Kevin] * Fix args[1] -> args[0] typo [Kevin] * Fix l2_offset -> offset typos tests/qemu-iotests/qed.py | 235 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 235 insertions(+) create mode 100755 tests/qemu-iotests/qed.py diff --git a/tests/qemu-iotests/qed.py b/tests/qemu-iotests/qed.py new file mode 100755 index 0000000..f06c074 --- /dev/null +++ b/tests/qemu-iotests/qed.py @@ -0,0 +1,235 @@ +#!/usr/bin/env python +# +# Tool to manipulate QED image files +# +# Copyright (C) 2010 IBM, Corp. +# +# Authors: +# Stefan Hajnoczi +# +# This work is licensed under the terms of the GNU GPL, version 2. See +# the COPYING file in the top-level directory. + +import sys +import struct +import random +import optparse + +# This can be used as a module +__all__ = ['QED_F_NEED_CHECK', 'QED'] + +QED_F_NEED_CHECK = 0x02 + +header_fmt = ']- Show header or l1/l2 tables''' + if not args or args[0] == 'header': + print qed.header + elif args[0] == 'l1': + print qed.l1_table + elif len(args) == 2 and args[0] == 'l2': + offset = int(args[1]) + print qed.read_table(offset) + else: + err('unrecognized sub-command') + +def cmd_duplicate(qed, table_level): + '''duplicate l1|l2 - Duplicate a random table element''' + if table_level == 'l1': + offset = qed.header['l1_table_offset'] + table = qed.l1_table + elif table_level == 'l2': + _, offset = random_table_item(qed.l1_table) + table = qed.read_table(offset) + else: + err('unrecognized sub-command') + corrupt_table_duplicate(table) + qed.write_table(offset, table) + +def cmd_invalidate(qed, table_level): + '''invalidate l1|l2 - Plant an invalid table element at random''' + if table_level == 'l1': + offset = qed.header['l1_table_offset'] + table = qed.l1_table + elif table_level == 'l2': + _, offset = random_table_item(qed.l1_table) + table = qed.read_table(offset) + else: + err('unrecognized sub-command') + corrupt_table_invalidate(qed, table) + qed.write_table(offset, table) + +def cmd_need_check(qed, *args): + '''need-check [on|off] - Test, set, or clear the QED_F_NEED_CHECK header bit''' + if not args: + print bool(qed.header['features'] & QED_F_NEED_CHECK) + return + + if args[0] == 'on': + qed.header['features'] |= QED_F_NEED_CHECK + elif args[0] == 'off': + qed.header['features'] &= ~QED_F_NEED_CHECK + else: + err('unrecognized sub-command') + qed.store_header() + +def cmd_zero_cluster(qed, pos, *args): + '''zero-cluster [] - Zero data clusters''' + pos, n = int(pos), 1 + if args: + if len(args) != 1: + err('expected one argument') + n = int(args[0]) + + for i in xrange(n): + l1_index = pos / qed.header['cluster_size'] / len(qed.l1_table) + if qed.l1_table[l1_index] == 0: + err('no l2 table allocated') + + l2_offset = qed.l1_table[l1_index] + l2_table = qed.read_table(l2_offset) + + l2_index = (pos / qed.header['cluster_size']) % len(qed.l1_table) + l2_table[l2_index] = 1 # zero the data cluster + qed.write_table(l2_offset, l2_table) + pos += qed.header['cluster_size'] + +def cmd_copy_metadata(qed, outfile): + '''copy-metadata - Copy metadata only (for scrubbing corrupted images)''' + out = open(outfile, 'wb') + + # Match file size + out.seek(qed.filesize - 1) + out.write('\0') + + # Copy header clusters + out.seek(0) + header_size_bytes = qed.header['header_size'] * qed.header['cluster_size'] + out.write(qed.raw_pread(0, header_size_bytes)) + + # Copy L1 table + out.seek(qed.header['l1_table_offset']) + s = ''.join(pack_table_elem(x) for x in qed.l1_table) + out.write(s) + + # Copy L2 tables + for l2_offset in qed.l1_table: + if l2_offset == 0: + continue + l2_table = qed.read_table(l2_offset) + out.seek(l2_offset) + s = ''.join(pack_table_elem(x) for x in l2_table) + out.write(s) + + out.close() + +def usage(): + print 'Usage: %s [, ...]' % sys.argv[0] + print + print 'Supported commands:' + for cmd in sorted(x for x in globals() if x.startswith('cmd_')): + print globals()[cmd].__doc__ + sys.exit(1) + +def main(): + if len(sys.argv) < 3: + usage() + filename, cmd = sys.argv[1:3] + + cmd = 'cmd_' + cmd.replace('-', '_') + if cmd not in globals(): + usage() + + qed = QED(open(filename, 'r+b')) + try: + globals()[cmd](qed, *sys.argv[3:]) + except TypeError, e: + sys.stderr.write(globals()[cmd].__doc__ + '\n') + sys.exit(1) + +if __name__ == '__main__': + main()