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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 73BCDC17441 for ; Mon, 11 Nov 2019 16:08:36 +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 42E2A2196E for ; Mon, 11 Nov 2019 16:08:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZQOdIj49" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 42E2A2196E 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]:54588 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iUCF1-0006MC-00 for qemu-devel@archiver.kernel.org; Mon, 11 Nov 2019 11:08:35 -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 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= 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) 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-Type: text/plain; charset=WINDOWS-1252 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+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 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