From nobody Mon Feb 9 01:19:33 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; 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=1568994120; cv=none; d=zoho.com; s=zohoarc; b=DXunslqwL4fJvXaDKj0nzoqyLdImwWGjAynassDZrCx216yOAetCaTIyD+N5U8v8KTTCKwLhpA8t4EJrir4SJ9ghVWvIRhvhF2kGzRDPI3oJDEFwx21YgSR6LBccuIjqBGUhboUb36OYWTvEGjSeNBnj1hk5tAcxI+Shqhnyz80= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1568994120; h=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:ARC-Authentication-Results; bh=ww4ZMieQzhlqya1OOO3vQ6DhpwZZBKeKmAJLLjCbuU8=; b=ZeaFkUGFUhLp89TJB3nV1759ISYJzi9njdpxY2sCNxpWjE4OJWNOZC1vg1/4YA25hfbkE7lKLEwSY3AzYg1yWfpKFb3GhmincmhXS3H5uNrIJ65yZv+K0z5XeIQ8yrIHHy5p7g3l16sfFJf3u+P/32eqqyt2xU+zyfzlrKLxARA= ARC-Authentication-Results: i=1; mx.zoho.com; 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 1568994120146681.51502789737; Fri, 20 Sep 2019 08:42:00 -0700 (PDT) Received: from localhost ([::1]:60990 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iBL2k-0003UL-8v for importer@patchew.org; Fri, 20 Sep 2019 11:41:58 -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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" 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 --- 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 **err= p) { @@ -6268,8 +6279,11 @@ 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 2.21.0