From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74DC8C3A5A2 for ; Fri, 20 Sep 2019 15:41:53 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4BCC5208C3 for ; Fri, 20 Sep 2019 15:41:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4BCC5208C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60990 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iBL2d-0003UL-Pn for qemu-devel@archiver.kernel.org; Fri, 20 Sep 2019 11:41:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:44029) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iBKpy-00011H-4b for qemu-devel@nongnu.org; Fri, 20 Sep 2019 11:28:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iBKpu-0004a4-7o for qemu-devel@nongnu.org; Fri, 20 Sep 2019 11:28:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42000) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iBKpl-0004VY-4E; Fri, 20 Sep 2019 11:28:33 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5A5223086228; Fri, 20 Sep 2019 15:28:32 +0000 (UTC) Received: from localhost (unknown [10.40.205.102]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E66BC100194E; Fri, 20 Sep 2019 15:28:31 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH 11/22] block: Use bdrv_recurse_can_replace() Date: Fri, 20 Sep 2019 17:27:53 +0200 Message-Id: <20190920152804.12875-12-mreitz@redhat.com> In-Reply-To: <20190920152804.12875-1-mreitz@redhat.com> References: <20190920152804.12875-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Fri, 20 Sep 2019 15:28:32 +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 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Alberto Garcia , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Let check_to_replace_node() use the more specialized bdrv_recurse_can_replace() instead of bdrv_recurse_is_first_non_filter(), which is too restrictive. Signed-off-by: Max Reitz --- block.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index a2deca4ac9..02177bde9a 100644 --- a/block.c +++ b/block.c @@ -6244,6 +6244,17 @@ bool bdrv_recurse_can_replace(BlockDriverState *bs= , return false; } =20 +/* + * Check whether the given @node_name can be replaced by a node that + * has the same data as @parent_bs. If so, return @node_name's BDS; + * NULL otherwise. + * + * @node_name must be a (recursive) *child of @parent_bs (or this + * function will return NULL). + * + * The result (whether the node can be replaced or not) is only valid + * for as long as no graph changes occur. + */ BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, const char *node_name, Error **e= rrp) { @@ -6268,8 +6279,11 @@ BlockDriverState *check_to_replace_node(BlockDrive= rState *parent_bs, * Another benefit is that this tests exclude backing files which ar= e * blocked by the backing blockers. */ - if (!bdrv_recurse_is_first_non_filter(parent_bs, to_replace_bs)) { - error_setg(errp, "Only top most non filter can be replaced"); + if (!bdrv_recurse_can_replace(parent_bs, to_replace_bs)) { + error_setg(errp, "Cannot replace '%s' by a node mirrored from '%= s', " + "because it cannot be guaranteed that doing so would = not " + "lead to an abrupt change of visible data", + node_name, parent_bs->node_name); to_replace_bs =3D NULL; goto out; } --=20 2.21.0