From nobody Mon Feb 9 09:15:46 2026 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; dkim=fail; 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 ARC-Seal: i=1; a=rsa-sha256; t=1573488522; cv=none; d=zoho.com; s=zohoarc; b=N7hCFkTMJgGmhbdzHgByrVeo0AFcC9B6QGpsPWoN3g6gfaf7V7O6TRA/kbJH7eE/ObgigfWBQRUgmCMfFZXFREj7y+4tgKdsfq5DvQotyjiAPb9KNIaybbrF4J/GQtVaVRH2Rb4FNEKXHNTThLPF28QzT40uVoKp0z0dbJV09Ok= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1573488522; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=twVsBJ1nTiS7APsE0cYdUcRoL6m6H4xxbgEn76Lc0nM=; b=Xw549ihbk+j+CAk8tyEd/T0+SePuF/GSBmYnLttoV+31CXCYil+LjfveS/ljzQeSiZ5cEmYelWKTv+EOIpavAio0O0A5qKJeoPJaxvf3bgBYSRU3v1xy6KG+XrphuMmH41J8W76y5naZPSI6ZKfSaISnmZQ0KnCsj67eQtR/q80= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; 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 header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1573488521994377.4755263668576; Mon, 11 Nov 2019 08:08:41 -0800 (PST) Received: from localhost ([::1]:54588 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iUCF6-0006MC-Fl for importer@patchew.org; Mon, 11 Nov 2019 11:08:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:39138) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iUC9g-00086u-MN for qemu-devel@nongnu.org; Mon, 11 Nov 2019 11:03:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iUC9a-0002rA-P4 for qemu-devel@nongnu.org; Mon, 11 Nov 2019 11:03:04 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:29639 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iUC9Z-0002qi-8k for qemu-devel@nongnu.org; Mon, 11 Nov 2019 11:02:58 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-323-NG-rArKoNnmFOz6kQclKpg-1; Mon, 11 Nov 2019 11:02:53 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BC9581005500; Mon, 11 Nov 2019 16:02:52 +0000 (UTC) Received: from localhost (ovpn-117-116.ams2.redhat.com [10.36.117.116]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 40A3B28D18; Mon, 11 Nov 2019 16:02:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1573488176; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=twVsBJ1nTiS7APsE0cYdUcRoL6m6H4xxbgEn76Lc0nM=; b=ZQOdIj49q/b45UxXnq6uJCs/MimEj7hgCLaszx7SOHjZSFV9rAknpErs6E60D0aHbTou1v WvpfZ30glPMZxIS8Rc1/JsvT+UqRxPZFTWT0xFsEV1eKbz+TiPmQaIK47jhd0XkZsprO4Y xmExIGSCza8EBMs85u+YQcFms86Uu7g= From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH for-5.0 v2 11/23] block: Use bdrv_recurse_can_replace() Date: Mon, 11 Nov 2019 17:02:04 +0100 Message-Id: <20191111160216.197086-12-mreitz@redhat.com> In-Reply-To: <20191111160216.197086-1-mreitz@redhat.com> References: <20191111160216.197086-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: NG-rArKoNnmFOz6kQclKpg-1 X-Mimecast-Spam-Score: 0 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: 207.211.31.120 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 , Vladimir Sementsov-Ogievskiy , Alberto Garcia , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" 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 Reviewed-by: Vladimir Sementsov-Ogievskiy --- block.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index de53addeb0..7608f21570 100644 --- a/block.c +++ b/block.c @@ -6243,6 +6243,17 @@ 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 **err= p) { @@ -6267,8 +6278,11 @@ BlockDriverState *check_to_replace_node(BlockDriverS= tate *parent_bs, * Another benefit is that this tests exclude backing files which are * 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 no= t " + "lead to an abrupt change of visible data", + node_name, parent_bs->node_name); to_replace_bs =3D NULL; goto out; } --=20 2.23.0