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, URIBL_BLOCKED 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 2712AC31E40 for ; Fri, 9 Aug 2019 16:30:12 +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 B1D47214C6 for ; Fri, 9 Aug 2019 16:30:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B1D47214C6 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]:32862 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hw7mM-0003SE-Of for qemu-devel@archiver.kernel.org; Fri, 09 Aug 2019 12:30:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57656) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hw7YE-0003yh-IG for qemu-devel@nongnu.org; Fri, 09 Aug 2019 12:15:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hw7YC-0004eZ-LA for qemu-devel@nongnu.org; Fri, 09 Aug 2019 12:15:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51518) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hw7Y9-0004cd-LU; Fri, 09 Aug 2019 12:15:29 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id EA5367EBC4; Fri, 9 Aug 2019 16:15:28 +0000 (UTC) Received: from localhost (unknown [10.40.205.179]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 858895D9D3; Fri, 9 Aug 2019 16:15:28 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Fri, 9 Aug 2019 18:13:58 +0200 Message-Id: <20190809161407.11920-34-mreitz@redhat.com> In-Reply-To: <20190809161407.11920-1-mreitz@redhat.com> References: <20190809161407.11920-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Fri, 09 Aug 2019 16:15:28 +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 Subject: [Qemu-devel] [PATCH v6 33/42] blockdev: Fix active commit choice 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 , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" We have to perform an active commit whenever the top node has a parent that has taken the WRITE permission on it. Signed-off-by: Max Reitz Reviewed-by: Vladimir Sementsov-Ogievskiy --- blockdev.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/blockdev.c b/blockdev.c index ee8b951154..4e72f6f701 100644 --- a/blockdev.c +++ b/blockdev.c @@ -3356,6 +3356,7 @@ void qmp_block_commit(bool has_job_id, const char *= job_id, const char *device, */ BlockdevOnError on_error =3D BLOCKDEV_ON_ERROR_REPORT; int job_flags =3D JOB_DEFAULT; + uint64_t top_perm, top_shared; =20 if (!has_speed) { speed =3D 0; @@ -3468,14 +3469,31 @@ void qmp_block_commit(bool has_job_id, const char= *job_id, const char *device, goto out; } =20 - if (top_bs =3D=3D bs) { + /* + * Active commit is required if and only if someone has taken a + * WRITE permission on the top node. Historically, we have always + * used active commit for top nodes, so continue that practice. + * (Active commit is never really wrong.) + */ + bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared); + if (top_perm & BLK_PERM_WRITE || + bdrv_skip_rw_filters(top_bs) =3D=3D bdrv_skip_rw_filters(bs)) + { if (has_backing_file) { error_setg(errp, "'backing-file' specified," " but 'top' is the active layer"); goto out; } - commit_active_start(has_job_id ? job_id : NULL, bs, base_bs, - job_flags, speed, on_error, + if (!has_job_id) { + /* + * Emulate here what block_job_create() does, because it + * is possible that @bs !=3D @top_bs (the block job should + * be named after @bs, even if @top_bs is the actual + * source) + */ + job_id =3D bdrv_get_device_name(bs); + } + commit_active_start(job_id, top_bs, base_bs, job_flags, speed, o= n_error, filter_node_name, NULL, NULL, false, &local_= err); } else { BlockDriverState *overlay_bs =3D bdrv_find_overlay(bs, top_bs); --=20 2.21.0