From nobody Tue Nov 4 15:31:26 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 1530200648068187.2875422595157; Thu, 28 Jun 2018 08:44:08 -0700 (PDT) Received: from localhost ([::1]:37209 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYZ5b-0000C2-Cv for importer@patchew.org; Thu, 28 Jun 2018 11:44:07 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34099) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYZ1U-0005Kf-8W for qemu-devel@nongnu.org; Thu, 28 Jun 2018 11:39:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fYZ1T-0006oT-ER for qemu-devel@nongnu.org; Thu, 28 Jun 2018 11:39:52 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:55610 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 1fYZ1Q-0006i9-Ui; Thu, 28 Jun 2018 11:39:49 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 812994076538; Thu, 28 Jun 2018 15:39:48 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-164.ams2.redhat.com [10.36.117.164]) by smtp.corp.redhat.com (Postfix) with ESMTP id 91C9723152; Thu, 28 Jun 2018 15:39:47 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Thu, 28 Jun 2018 17:39:36 +0200 Message-Id: <20180628153937.26097-3-kwolf@redhat.com> In-Reply-To: <20180628153937.26097-1-kwolf@redhat.com> References: <20180628153937.26097-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Thu, 28 Jun 2018 15:39:48 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Thu, 28 Jun 2018 15:39:48 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kwolf@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] [PATCH 2/3] qcow2: Free allocated clusters on write error 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: kwolf@redhat.com, berto@igalia.com, qemu-devel@nongnu.org, mreitz@redhat.com 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" If we managed to allocate the clusters, but then failed to write the data, there's a good chance that we'll still be able to free the clusters again in order to avoid cluster leaks (the refcounts are cached, so even if we can't write them out right now, we may be able to do so when the VM is resumed after a werror=3Dstop/enospc pause). Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Tested-by: Eric Blake --- block/qcow2.h | 1 + block/qcow2-cluster.c | 11 +++++++++++ block/qcow2.c | 2 ++ 3 files changed, 14 insertions(+) diff --git a/block/qcow2.h b/block/qcow2.h index 01b5250415..1c9c0d3631 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -614,6 +614,7 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDri= verState *bs, int compressed_size); =20 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m); +void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m); int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset, uint64_t bytes, enum qcow2_discard_type type, bool full_discard); diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 0d74584c9b..d37fe08b3d 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -994,6 +994,17 @@ err: return ret; } =20 +/** + * Frees the allocated clusters because the request failed and they won't + * actually be linked. + */ +void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m) +{ + BDRVQcow2State *s =3D bs->opaque; + qcow2_free_clusters(bs, m->alloc_offset, m->nb_clusters << s->cluster_= bits, + QCOW2_DISCARD_NEVER); +} + /* * Returns the number of contiguous clusters that can be used for an alloc= ating * write, but require COW to be performed (this includes yet unallocated s= pace, diff --git a/block/qcow2.c b/block/qcow2.c index da54b2c8f8..7a4db12afd 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1777,6 +1777,8 @@ static coroutine_fn int qcow2_handle_l2meta(BlockDriv= erState *bs, if (ret) { goto out; } + } else { + qcow2_alloc_cluster_abort(bs, l2meta); } =20 /* Take the request off the list of running requests */ --=20 2.13.6