From nobody Mon Feb 9 01:19:59 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 1488901641072372.1776017215127; Tue, 7 Mar 2017 07:47:21 -0800 (PST) Received: from localhost ([::1]:51279 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1clHKY-0006ww-KU for importer@patchew.org; Tue, 07 Mar 2017 10:47:18 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42482) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1clHEg-00029D-L0 for qemu-devel@nongnu.org; Tue, 07 Mar 2017 10:41:15 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1clHEf-0002gV-HD for qemu-devel@nongnu.org; Tue, 07 Mar 2017 10:41:14 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37360) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1clHEa-0002Xq-4J; Tue, 07 Mar 2017 10:41:08 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (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 38EE61555E; Tue, 7 Mar 2017 15:41:07 +0000 (UTC) Received: from noname.str.redhat.com (dhcp-192-197.str.redhat.com [10.33.192.197]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v27FeuUZ032123; Tue, 7 Mar 2017 10:41:05 -0500 From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 7 Mar 2017 16:40:30 +0100 Message-Id: <1488901251-16214-7-git-send-email-kwolf@redhat.com> In-Reply-To: <1488901251-16214-1-git-send-email-kwolf@redhat.com> References: <1488901251-16214-1-git-send-email-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 07 Mar 2017 15:41:08 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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] [PULL 06/27] block: Factor out should_update_child() 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, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" Signed-off-by: Kevin Wolf Reviewed-by: Fam Zheng Reviewed-by: Eric Blake Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- block.c | 42 +++++++++++++++++++++++++++--------------- 1 file changed, 27 insertions(+), 15 deletions(-) diff --git a/block.c b/block.c index f293ccb..6dc02b8 100644 --- a/block.c +++ b/block.c @@ -2886,28 +2886,40 @@ void bdrv_close_all(void) assert(QTAILQ_EMPTY(&all_bdrv_states)); } =20 +static bool should_update_child(BdrvChild *c, BlockDriverState *to) +{ + BdrvChild *to_c; + + if (c->role->stay_at_node) { + return false; + } + + if (c->role =3D=3D &child_backing) { + /* If @from is a backing file of @to, ignore the child to avoid + * creating a loop. We only want to change the pointer of other + * parents. */ + QLIST_FOREACH(to_c, &to->children, next) { + if (to_c =3D=3D c) { + break; + } + } + if (to_c) { + return false; + } + } + + return true; +} + static void change_parent_backing_link(BlockDriverState *from, BlockDriverState *to) { - BdrvChild *c, *next, *to_c; + BdrvChild *c, *next; =20 QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { - if (c->role->stay_at_node) { + if (!should_update_child(c, to)) { continue; } - if (c->role =3D=3D &child_backing) { - /* If @from is a backing file of @to, ignore the child to avoid - * creating a loop. We only want to change the pointer of other - * parents. */ - QLIST_FOREACH(to_c, &to->children, next) { - if (to_c =3D=3D c) { - break; - } - } - if (to_c) { - continue; - } - } =20 bdrv_ref(to); /* FIXME Are we sure that bdrv_replace_child() can't run into --=20 1.8.3.1