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=-8.1 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,USER_AGENT_SANE_1 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 B8E52C35247 for ; Wed, 5 Feb 2020 15:58:46 +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 84C80217BA for ; Wed, 5 Feb 2020 15:58:46 +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="dMe3y+xG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 84C80217BA 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]:51484 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1izN4f-00039H-Pb for qemu-devel@archiver.kernel.org; Wed, 05 Feb 2020 10:58:45 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:43489) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1izN3t-0002G6-Rs for qemu-devel@nongnu.org; Wed, 05 Feb 2020 10:57:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1izN3s-0000Qj-PF for qemu-devel@nongnu.org; Wed, 05 Feb 2020 10:57:57 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:49708 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 1izN3s-0000PN-L6 for qemu-devel@nongnu.org; Wed, 05 Feb 2020 10:57:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580918276; 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=wNh66nqG88VDB/dTueM8CwMFfxrzQzqXs730fSe4qS0=; b=dMe3y+xGjG037W9yPOeVPB9qG9TfO4qebQIJB9eOh26lS+h14LllOWCgrYOSQAWVQfZ6eb 6rmyenKhIq0p4VOVvxsT7xwbO91O4Loaa7Mbk9jE5UVr+/AbROg6OkFcAVKQRfZ7+V91C9 DDBXhxT8rvogteMdzsqnfi5J7JRDWUA= 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-315-ijGVvfilMHKvm37LXLk4wA-1; Wed, 05 Feb 2020 10:57:52 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6FAC18010EF; Wed, 5 Feb 2020 15:57:51 +0000 (UTC) Received: from dhcp-200-226.str.redhat.com (dhcp-200-226.str.redhat.com [10.33.200.226]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 07E6D857AE; Wed, 5 Feb 2020 15:57:49 +0000 (UTC) Date: Wed, 5 Feb 2020 16:57:48 +0100 From: Kevin Wolf To: Max Reitz Subject: Re: [PATCH for-5.0 v2 11/23] block: Use bdrv_recurse_can_replace() Message-ID: <20200205155748.GG5768@dhcp-200-226.str.redhat.com> References: <20191111160216.197086-1-mreitz@redhat.com> <20191111160216.197086-12-mreitz@redhat.com> MIME-Version: 1.0 In-Reply-To: <20191111160216.197086-12-mreitz@redhat.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: ijGVvfilMHKvm37LXLk4wA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline 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: Vladimir Sementsov-Ogievskiy , Alberto Garcia , qemu-devel@nongnu.org, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 11.11.2019 um 17:02 hat Max Reitz geschrieben: > 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. >=20 > Signed-off-by: Max Reitz > --- > block.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) >=20 > 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 **e= rrp) > { > @@ -6267,8 +6278,11 @@ 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); If this function is only supposed to be used in the context of the mirror job, moving it into block/mirror.c could be considered as a cleanup on top. Kevin