From nobody Mon Feb 9 20:58:47 2026 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.zoho.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; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1487008117427822.882691925392; Mon, 13 Feb 2017 09:48:37 -0800 (PST) Received: from localhost ([::1]:58492 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cdKjr-0001G9-Qd for importer@patchew.org; Mon, 13 Feb 2017 12:48:35 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59552) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cdKMA-0003V6-0s for qemu-devel@nongnu.org; Mon, 13 Feb 2017 12:24:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cdKM8-0006EG-Ml for qemu-devel@nongnu.org; Mon, 13 Feb 2017 12:24:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59366) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cdKM5-0006CW-Jj; Mon, 13 Feb 2017 12:24:01 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 786EE81236; Mon, 13 Feb 2017 17:24:01 +0000 (UTC) Received: from noname.redhat.com (ovpn-117-183.ams2.redhat.com [10.36.117.183]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1DHNC3e031842; Mon, 13 Feb 2017 12:23:59 -0500 From: Kevin Wolf To: qemu-block@nongnu.org Date: Mon, 13 Feb 2017 18:22:46 +0100 Message-Id: <1487006583-24350-25-git-send-email-kwolf@redhat.com> In-Reply-To: <1487006583-24350-1-git-send-email-kwolf@redhat.com> References: <1487006583-24350-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Mon, 13 Feb 2017 17:24:01 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC PATCH 24/41] block: Add BdrvChildRole.stay_at_node 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, jcody@redhat.com, famz@redhat.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" When the parents' child links are updated in bdrv_append() or bdrv_replace_in_backing_chain(), this should affect all child links of BlockBackends or other nodes, but not on child links held for other purposes (like for setting permissions). This patch allows to control the behaviour per BdrvChildRole. Signed-off-by: Kevin Wolf --- block.c | 3 +++ include/block/block_int.h | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/block.c b/block.c index d743f50..842ac78 100644 --- a/block.c +++ b/block.c @@ -2713,6 +2713,9 @@ static void change_parent_backing_link(BlockDriverSta= te *from, BdrvChild *c, *next, *to_c; =20 QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { + if (c->role->stay_at_node) { + continue; + } if (c->role =3D=3D &child_backing) { /* @from is generally not allowed to be a backing file, except= for * when @to is the overlay. In that case, @from may not be rep= laced diff --git a/include/block/block_int.h b/include/block/block_int.h index a5557b1..b24fc49 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -427,6 +427,10 @@ typedef struct BdrvAioNotifier { } BdrvAioNotifier; =20 struct BdrvChildRole { + /* If true, bdrv_replace_in_backing_chain() doesn't change the node th= is + * BdrvChild points to. */ + bool stay_at_node; + void (*inherit_options)(int *child_flags, QDict *child_options, int parent_flags, QDict *parent_options); =20 --=20 1.8.3.1