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 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 33692C31E46 for ; Wed, 12 Jun 2019 22:27:42 +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 0697C208C2 for ; Wed, 12 Jun 2019 22:27:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0697C208C2 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]:35502 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBiX-0005Bt-AY for qemu-devel@archiver.kernel.org; Wed, 12 Jun 2019 18:27:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45320) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBRw-0007Iq-88 for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:10:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hbBRu-0007WS-E0 for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:10:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40826) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hbBRm-0007QJ-DF; Wed, 12 Jun 2019 18:10:24 -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 07DBC7FDFF; Wed, 12 Jun 2019 22:10:20 +0000 (UTC) Received: from localhost (unknown [10.40.205.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8B8131001B0F; Wed, 12 Jun 2019 22:10:19 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Thu, 13 Jun 2019 00:09:27 +0200 Message-Id: <20190612221004.2317-6-mreitz@redhat.com> In-Reply-To: <20190612221004.2317-1-mreitz@redhat.com> References: <20190612221004.2317-1-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 [10.5.110.27]); Wed, 12 Jun 2019 22:10:20 +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 v5 05/42] block: Add chain helper functions 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" Add some helper functions for skipping filters in a chain of block nodes. Signed-off-by: Max Reitz --- include/block/block_int.h | 3 +++ block.c | 55 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) diff --git a/include/block/block_int.h b/include/block/block_int.h index 7ce71623f8..875a33f255 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -1264,6 +1264,9 @@ BdrvChild *bdrv_filtered_child(BlockDriverState *bs= ); BdrvChild *bdrv_metadata_child(BlockDriverState *bs); BdrvChild *bdrv_storage_child(BlockDriverState *bs); BdrvChild *bdrv_primary_child(BlockDriverState *bs); +BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs); +BlockDriverState *bdrv_skip_rw_filters(BlockDriverState *bs); +BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs); =20 static inline BlockDriverState *child_bs(BdrvChild *child) { diff --git a/block.c b/block.c index 724d8889a6..be18130944 100644 --- a/block.c +++ b/block.c @@ -6494,3 +6494,58 @@ BdrvChild *bdrv_primary_child(BlockDriverState *bs= ) { return bdrv_filtered_rw_child(bs) ?: bs->file; } + +static BlockDriverState *bdrv_skip_filters(BlockDriverState *bs, + bool stop_on_explicit_filter) +{ + BdrvChild *filtered; + + if (!bs) { + return NULL; + } + + while (!(stop_on_explicit_filter && !bs->implicit)) { + filtered =3D bdrv_filtered_rw_child(bs); + if (!filtered) { + break; + } + bs =3D filtered->bs; + } + /* + * Note that this treats nodes with bs->drv =3D=3D NULL as not being + * R/W filters (bs->drv =3D=3D NULL should be replaced by something + * else anyway). + * The advantage of this behavior is that this function will thus + * always return a non-NULL value (given a non-NULL @bs). + */ + + return bs; +} + +/* + * Return the first BDS that has not been added implicitly or that + * does not have an RW-filtered child down the chain starting from @bs + * (including @bs itself). + */ +BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs) +{ + return bdrv_skip_filters(bs, true); +} + +/* + * Return the first BDS that does not have an RW-filtered child down + * the chain starting from @bs (including @bs itself). + */ +BlockDriverState *bdrv_skip_rw_filters(BlockDriverState *bs) +{ + return bdrv_skip_filters(bs, false); +} + +/* + * For a backing chain, return the first non-filter backing image of + * the first non-filter image. + */ +BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs) +{ + return bdrv_skip_rw_filters(bdrv_filtered_cow_bs(bdrv_skip_rw_filter= s(bs))); +} --=20 2.21.0