From nobody Mon Feb 9 20:35:27 2026 Delivered-To: importer@patchew.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 ARC-Seal: i=1; a=rsa-sha256; t=1598971595; cv=none; d=zohomail.com; s=zohoarc; b=g09QXsWhxMs569xTfxZEU2UR6+rQbyuC0DRwwKNlTcewYRlqIIh9J40sU0LhUM5LofBHZDLWR71ia6wf1SJPikTw4l+Ub71FwpI156J857rJ1vBHSnnzuBwONTPoZGjPq3MNMF6MTihLukLPAlngvx1uBv9o1+f7DmuRc7JsmCY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1598971595; h=Content-Type: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; bh=TZMCvRr/gr8uIS8CUb7UrY9RH9CHCEaAuADxPZ35rAg=; b=F/ptHlatRy5KS3E930m0mVoT0Zru7Kx1/ZtDHhitFuJTCFeJItgC6W5et0oZo5bxwvDquVZOP1Ww8gLZn0encsUVctNEStrceAnZepYX/qMYxXQ9i8NvaAn0u/GmQc2pb+V6YkwFKsBVuos47Z277rcVjsn7YtQ9Qm60iavkxqE= ARC-Authentication-Results: i=1; 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 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 15989715955181007.3621719143632; Tue, 1 Sep 2020 07:46:35 -0700 (PDT) Received: from localhost ([::1]:37412 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kD7YQ-0004fX-Nj for importer@patchew.org; Tue, 01 Sep 2020 10:46:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33640) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kD7Mt-00072h-Kx for qemu-devel@nongnu.org; Tue, 01 Sep 2020 10:34:39 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:30412 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kD7Mp-000739-JF for qemu-devel@nongnu.org; Tue, 01 Sep 2020 10:34:39 -0400 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-10-IOe6QSMFOESfF5d_XyASGg-1; Tue, 01 Sep 2020 10:34:32 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8649A1015C98; Tue, 1 Sep 2020 14:34:31 +0000 (UTC) Received: from localhost (ovpn-113-83.ams2.redhat.com [10.36.113.83]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 29E5A5C1A3; Tue, 1 Sep 2020 14:34:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598970874; 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=TZMCvRr/gr8uIS8CUb7UrY9RH9CHCEaAuADxPZ35rAg=; b=dLqKsv4VR7RQNhoieJ+2chbPYg7EPnePV41LpxXXRtOpvLTAu+IH9Les+/PV6JYTPu0n9w lZx6bY0gGnKdgNx0VVCHCokIXcgQaALYHrwKJv1psVRhVZtRmBuw9cs4J+tNbvyNBWOTaS utgdyopjeZgEFQdX+4+KmSVq2XImZJQ= X-MC-Unique: IOe6QSMFOESfF5d_XyASGg-1 From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH v8 02/43] block: Add chain helper functions Date: Tue, 1 Sep 2020 16:33:43 +0200 Message-Id: <20200901143424.884735-3-mreitz@redhat.com> In-Reply-To: <20200901143424.884735-1-mreitz@redhat.com> References: <20200901143424.884735-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable 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; Received-SPF: pass client-ip=205.139.110.120; envelope-from=mreitz@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/01 05:11:36 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action 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 , Andrey Shinkevich , Vladimir Sementsov-Ogievskiy , 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" 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 | 62 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+) diff --git a/include/block/block_int.h b/include/block/block_int.h index f280a95b26..8205ccaa62 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -1394,6 +1394,9 @@ BdrvChild *bdrv_cow_child(BlockDriverState *bs); BdrvChild *bdrv_filter_child(BlockDriverState *bs); BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs); BdrvChild *bdrv_primary_child(BlockDriverState *bs); +BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs); +BlockDriverState *bdrv_skip_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 9f866e8676..b162142609 100644 --- a/block.c +++ b/block.c @@ -7034,3 +7034,65 @@ BdrvChild *bdrv_primary_child(BlockDriverState *bs) =20 return found; } + +static BlockDriverState *bdrv_do_skip_filters(BlockDriverState *bs, + bool stop_on_explicit_filter) +{ + BdrvChild *c; + + if (!bs) { + return NULL; + } + + while (!(stop_on_explicit_filter && !bs->implicit)) { + c =3D bdrv_filter_child(bs); + if (!c) { + /* + * A filter that is embedded in a working block graph must + * have a child. Assert this here so this function does + * not return a filter node that is not expected by the + * caller. + */ + assert(!bs->drv || !bs->drv->is_filter); + break; + } + bs =3D c->bs; + } + /* + * Note that this treats nodes with bs->drv =3D=3D NULL as not being + * 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 a filtered child down the chain starting from @bs + * (including @bs itself). + */ +BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs) +{ + return bdrv_do_skip_filters(bs, true); +} + +/* + * Return the first BDS that does not have a filtered child down the + * chain starting from @bs (including @bs itself). + */ +BlockDriverState *bdrv_skip_filters(BlockDriverState *bs) +{ + return bdrv_do_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_filters(bdrv_cow_bs(bdrv_skip_filters(bs))); +} --=20 2.26.2