From nobody Wed Apr 16 08:02:49 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1528727736999923.9908712689476; Mon, 11 Jun 2018 07:35:36 -0700 (PDT) Received: from localhost ([::1]:49189 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fSNuu-0002oB-6g for importer@patchew.org; Mon, 11 Jun 2018 10:35:32 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53006) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fSNmJ-0004Sr-Vc for qemu-devel@nongnu.org; Mon, 11 Jun 2018 10:26:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fSNmI-0001jH-NQ for qemu-devel@nongnu.org; Mon, 11 Jun 2018 10:26:39 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:35522 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fSNmF-0001fg-KQ; Mon, 11 Jun 2018 10:26:35 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0DA3ABB409; Mon, 11 Jun 2018 14:26:35 +0000 (UTC) Received: from localhost (unknown [10.40.205.155]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 82C0F100294B; Mon, 11 Jun 2018 14:26:34 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Mon, 11 Jun 2018 16:25:53 +0200 Message-Id: <20180611142611.6609-12-mreitz@redhat.com> In-Reply-To: <20180611142611.6609-1-mreitz@redhat.com> References: <20180611142611.6609-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 11 Jun 2018 14:26:35 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 11 Jun 2018 14:26:35 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'mreitz@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PULL 11/29] qcow2: Repair OFLAG_COPIED when fixing leaks X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Peter Maydell , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Repairing OFLAG_COPIED is usually safe because it is done after the refcounts have been repaired. Therefore, it we did not find anyone else referencing a data or L2 cluster, it makes no sense to not set OFLAG_COPIED -- and the other direction (clearing OFLAG_COPIED) is always safe, anyway, it may just induce leaks. Furthermore, if OFLAG_COPIED is actually consistent with a wrong (leaky) refcount, we will decrement the refcount with -r leaks, but OFLAG_COPIED will then be wrong. qemu-img check should not produce images that are more corrupted afterwards then they were before. Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=3D1527085 Signed-off-by: Max Reitz Reviewed-by: Eric Blake Message-id: 20180509200059.31125-2-mreitz@redhat.com Signed-off-by: Max Reitz --- block/qcow2-refcount.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 403236256b..18c729aa27 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1799,6 +1799,19 @@ static int check_oflag_copied(BlockDriverState *bs, = BdrvCheckResult *res, int ret; uint64_t refcount; int i, j; + bool repair; + + if (fix & BDRV_FIX_ERRORS) { + /* Always repair */ + repair =3D true; + } else if (fix & BDRV_FIX_LEAKS) { + /* Repair only if that seems safe: This function is always + * called after the refcounts have been fixed, so the refcount + * is accurate if that repair was successful */ + repair =3D !res->check_errors && !res->corruptions && !res->leaks; + } else { + repair =3D false; + } =20 for (i =3D 0; i < s->l1_size; i++) { uint64_t l1_entry =3D s->l1_table[i]; @@ -1818,10 +1831,8 @@ static int check_oflag_copied(BlockDriverState *bs, = BdrvCheckResult *res, if ((refcount =3D=3D 1) !=3D ((l1_entry & QCOW_OFLAG_COPIED) !=3D = 0)) { fprintf(stderr, "%s OFLAG_COPIED L2 cluster: l1_index=3D%d " "l1_entry=3D%" PRIx64 " refcount=3D%" PRIu64 "\n", - fix & BDRV_FIX_ERRORS ? "Repairing" : - "ERROR", - i, l1_entry, refcount); - if (fix & BDRV_FIX_ERRORS) { + repair ? "Repairing" : "ERROR", i, l1_entry, refcount); + if (repair) { s->l1_table[i] =3D refcount =3D=3D 1 ? l1_entry | QCOW_OFLAG_COPIED : l1_entry & ~QCOW_OFLAG_COPIED; @@ -1862,10 +1873,8 @@ static int check_oflag_copied(BlockDriverState *bs, = BdrvCheckResult *res, if ((refcount =3D=3D 1) !=3D ((l2_entry & QCOW_OFLAG_COPIE= D) !=3D 0)) { fprintf(stderr, "%s OFLAG_COPIED data cluster: " "l2_entry=3D%" PRIx64 " refcount=3D%" PRIu64 "= \n", - fix & BDRV_FIX_ERRORS ? "Repairing" : - "ERROR", - l2_entry, refcount); - if (fix & BDRV_FIX_ERRORS) { + repair ? "Repairing" : "ERROR", l2_entry, refc= ount); + if (repair) { l2_table[j] =3D cpu_to_be64(refcount =3D=3D 1 ? l2_entry | QCOW_OFLAG_COPIED : l2_entry & ~QCOW_OFLAG_COPIED); --=20 2.17.1