From nobody Thu Dec 18 19:31:07 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; 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 209.51.188.17 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 [209.51.188.17]) by mx.zohomail.com with SMTPS id 1552415240386260.61136933655564; Tue, 12 Mar 2019 11:27:20 -0700 (PDT) Received: from localhost ([127.0.0.1]:57406 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h3m7R-0008Fr-Dk for importer@patchew.org; Tue, 12 Mar 2019 14:27:17 -0400 Received: from eggs.gnu.org ([209.51.188.92]:56742) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h3lF0-0001Ai-Kz for qemu-devel@nongnu.org; Tue, 12 Mar 2019 13:31:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h3lEz-0000Ff-38 for qemu-devel@nongnu.org; Tue, 12 Mar 2019 13:31:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47698) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1h3lEv-0000AL-0l; Tue, 12 Mar 2019 13:30:57 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 102703007C5F; Tue, 12 Mar 2019 17:30:56 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-117-52.ams2.redhat.com [10.36.117.52]) by smtp.corp.redhat.com (Postfix) with ESMTP id 012C260C73; Tue, 12 Mar 2019 17:30:54 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 12 Mar 2019 18:30:14 +0100 Message-Id: <20190312173025.3843-18-kwolf@redhat.com> In-Reply-To: <20190312173025.3843-1-kwolf@redhat.com> References: <20190312173025.3843-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Tue, 12 Mar 2019 17:30:56 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 17/28] block: Freeze the backing chain for the duration of the commit job 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, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" From: Alberto Garcia Signed-off-by: Alberto Garcia Signed-off-by: Kevin Wolf --- block/commit.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/block/commit.c b/block/commit.c index 3b46ca7f97..ba60fef58a 100644 --- a/block/commit.c +++ b/block/commit.c @@ -39,6 +39,7 @@ typedef struct CommitBlockJob { BlockDriverState *base_bs; BlockdevOnError on_error; bool base_read_only; + bool chain_frozen; char *backing_file_str; } CommitBlockJob; =20 @@ -68,6 +69,9 @@ static int commit_prepare(Job *job) { CommitBlockJob *s =3D container_of(job, CommitBlockJob, common.job); =20 + bdrv_unfreeze_backing_chain(s->commit_top_bs, s->base_bs); + s->chain_frozen =3D false; + /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before * the normal backing chain can be restored. */ blk_unref(s->base); @@ -84,6 +88,10 @@ static void commit_abort(Job *job) CommitBlockJob *s =3D container_of(job, CommitBlockJob, common.job); BlockDriverState *top_bs =3D blk_bs(s->top); =20 + if (s->chain_frozen) { + bdrv_unfreeze_backing_chain(s->commit_top_bs, s->base_bs); + } + /* Make sure commit_top_bs and top stay around until bdrv_replace_node= () */ bdrv_ref(top_bs); bdrv_ref(s->commit_top_bs); @@ -330,6 +338,11 @@ void commit_start(const char *job_id, BlockDriverState= *bs, } } =20 + if (bdrv_freeze_backing_chain(commit_top_bs, base, errp) < 0) { + goto fail; + } + s->chain_frozen =3D true; + ret =3D block_job_add_bdrv(&s->common, "base", base, 0, BLK_PERM_ALL, = errp); if (ret < 0) { goto fail; @@ -362,6 +375,9 @@ void commit_start(const char *job_id, BlockDriverState = *bs, return; =20 fail: + if (s->chain_frozen) { + bdrv_unfreeze_backing_chain(commit_top_bs, base); + } if (s->base) { blk_unref(s->base); } --=20 2.20.1