From nobody Thu Nov 13 19:24:56 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.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 (zohomail.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 Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1582030401935220.43687078550704; Tue, 18 Feb 2020 04:53:21 -0800 (PST) Received: from localhost ([::1]:34054 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j42NM-0004V7-UO for importer@patchew.org; Tue, 18 Feb 2020 07:53:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38985) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j42Dj-0004Vk-9h for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:24 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j42Dh-0001CR-Uv for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:23 -0500 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:43181 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j42Dh-0001By-RN for qemu-devel@nongnu.org; Tue, 18 Feb 2020 07:43:21 -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-156-UkhfGE7GMsOV8BZxrnY11Q-1; Tue, 18 Feb 2020 07:43:19 -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 EB4DA8010F0; Tue, 18 Feb 2020 12:43:18 +0000 (UTC) Received: from localhost (unknown [10.36.118.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 666118B564; Tue, 18 Feb 2020 12:43:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582029801; 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=TQKOddGHQBKAwo99MiEARBSo9qMz3oh0fxqkpLF66PE=; b=R5WMwxKZNfCuAk1c4ygyjFinTD0aJ7lEGk05oFfANTx6SBRC4pDp58GJYJEzpKcSXGQtma 5wbTKR9X6GnzBtEMpgdK+AJCNXJYkW0VLi1JRqq9en1i86Gzl6dPT6QaJvMadtSdeAlNjo b08J5x5d/C3TyRmrAZEG1IRXcZc3mPw= From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH v3 10/33] block: Use bdrv_inherited_options() Date: Tue, 18 Feb 2020 13:42:19 +0100 Message-Id: <20200218124242.584644-11-mreitz@redhat.com> In-Reply-To: <20200218124242.584644-1-mreitz@redhat.com> References: <20200218124242.584644-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: UkhfGE7GMsOV8BZxrnY11Q-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 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 , 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 child_file's, child_format's, and child_backing's .inherit_options() implementations fall back to bdrv_inherited_options() to show that it would really work for all of these cases, if only the parents passed the appropriate BdrvChildRole and parent_is_format values. (Also, make bdrv_open_inherit(), the only place to explicitly call bdrv_backing_options(), call bdrv_inherited_options() instead.) This patch should incur only two visible changes, both for child_format children, both of which are effectively bug fixes: First, they no longer have discard=3Dunmap set by default. This reason it was set is because bdrv_inherited_fmt_options() fell through to bdrv_protocol_options(), and that set it because "format drivers take care to send flushes and respect unmap policy". None of the drivers that use child_format for their children (quorum and blkverify) are format drivers, though, so this reasoning does not apply here. Second, they no longer have BDRV_O_NO_IO force-cleared. child_format was used solely for children that do not store any metadata and as such will not be accessed by their parents as long as those parents do not receive I/O themselves. Thus, such children should inherit BDRV_O_NO_IO. Signed-off-by: Max Reitz Reviewed-by: Eric Blake --- block.c | 66 ++++++++++++--------------------------------------------- 1 file changed, 14 insertions(+), 52 deletions(-) diff --git a/block.c b/block.c index 9179b9b604..aa54d40e4f 100644 --- a/block.c +++ b/block.c @@ -1002,10 +1002,9 @@ static void bdrv_temp_snapshot_options(int *child_fl= ags, QDict *child_options, * Returns the options and flags that a generic child of a BDS should * get, based on the given options and flags for the parent BDS. */ -static void __attribute__((unused)) - bdrv_inherited_options(BdrvChildRole role, bool parent_is_format, - int *child_flags, QDict *child_options, - int parent_flags, QDict *parent_options) +static void bdrv_inherited_options(BdrvChildRole role, bool parent_is_form= at, + int *child_flags, QDict *child_options, + int parent_flags, QDict *parent_options) { int flags =3D parent_flags; =20 @@ -1090,31 +1089,9 @@ static void bdrv_protocol_options(BdrvChildRole role= , bool parent_is_format, int *child_flags, QDict *child_options, int parent_flags, QDict *parent_options) { - int flags =3D parent_flags; - - /* Enable protocol handling, disable format probing for bs->file */ - flags |=3D BDRV_O_PROTOCOL; - - /* If the cache mode isn't explicitly set, inherit direct and no-flush= from - * the parent. */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIREC= T); - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FL= USH); - qdict_copy_default(child_options, parent_options, BDRV_OPT_FORCE_SHARE= ); - - /* Inherit the read-only option from the parent if it's not set */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); - qdict_copy_default(child_options, parent_options, BDRV_OPT_AUTO_READ_O= NLY); - - /* Our block drivers take care to send flushes and respect unmap polic= y, - * so we can default to enable both on lower layers regardless of the - * corresponding parent options. */ - qdict_set_default_str(child_options, BDRV_OPT_DISCARD, "unmap"); - - /* Clear flags that only apply to the top layer */ - flags &=3D ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ= | - BDRV_O_NO_IO); - - *child_flags =3D flags; + bdrv_inherited_options(BDRV_CHILD_IMAGE, true, + child_flags, child_options, + parent_flags, parent_options); } =20 const BdrvChildClass child_file =3D { @@ -1141,11 +1118,9 @@ static void bdrv_inherited_fmt_options(BdrvChildRole= role, int *child_flags, QDict *child_opti= ons, int parent_flags, QDict *parent_opt= ions) { - child_file.inherit_options(role, parent_is_format, - child_flags, child_options, - parent_flags, parent_options); - - *child_flags &=3D ~(BDRV_O_PROTOCOL | BDRV_O_NO_IO); + bdrv_inherited_options(BDRV_CHILD_DATA, false, + child_flags, child_options, + parent_flags, parent_options); } =20 const BdrvChildClass child_format =3D { @@ -1227,23 +1202,9 @@ static void bdrv_backing_options(BdrvChildRole role,= bool parent_is_format, int *child_flags, QDict *child_options, int parent_flags, QDict *parent_options) { - int flags =3D parent_flags; - - /* The cache mode is inherited unmodified for backing files; except WC= E, - * which is only applied on the top level (BlockBackend) */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIREC= T); - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FL= USH); - qdict_copy_default(child_options, parent_options, BDRV_OPT_FORCE_SHARE= ); - - /* backing files always opened read-only */ - qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "on"); - qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); - flags &=3D ~BDRV_O_COPY_ON_READ; - - /* snapshot=3Don is handled on the top layer */ - flags &=3D ~(BDRV_O_SNAPSHOT | BDRV_O_TEMPORARY); - - *child_flags =3D flags; + bdrv_inherited_options(BDRV_CHILD_COW, true, + child_flags, child_options, + parent_flags, parent_options); } =20 static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *ba= se, @@ -3144,7 +3105,8 @@ static BlockDriverState *bdrv_open_inherit(const char= *filename, flags, options); /* Let bdrv_backing_options() override "read-only" */ qdict_del(options, BDRV_OPT_READ_ONLY); - bdrv_backing_options(0, true, &flags, options, flags, options); + bdrv_inherited_options(BDRV_CHILD_COW, true, + &flags, options, flags, options); } =20 bs->open_flags =3D flags; --=20 2.24.1