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 EED5FC31E46 for ; Wed, 12 Jun 2019 22:32:29 +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 C2882208C2 for ; Wed, 12 Jun 2019 22:32:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2882208C2 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]:35538 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBnA-00028W-0i for qemu-devel@archiver.kernel.org; Wed, 12 Jun 2019 18:32:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45607) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBSB-0007kA-DV for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:10:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hbBSA-0007iz-2x for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:10:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37240) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hbBS7-0007hF-Dz; Wed, 12 Jun 2019 18:10:43 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B778780461; Wed, 12 Jun 2019 22:10:42 +0000 (UTC) Received: from localhost (unknown [10.40.205.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 468887E692; Wed, 12 Jun 2019 22:10:42 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Thu, 13 Jun 2019 00:09:36 +0200 Message-Id: <20190612221004.2317-15-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 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 12 Jun 2019 22:10:42 +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 14/42] block: Use CAFs when working with backing chains 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" Use child access functions when iterating through backing chains so filters do not break the chain. Signed-off-by: Max Reitz --- block.c | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/block.c b/block.c index 11f37983d9..505b3e9a01 100644 --- a/block.c +++ b/block.c @@ -4261,7 +4261,8 @@ int bdrv_change_backing_file(BlockDriverState *bs, } =20 /* - * Finds the image layer in the chain that has 'bs' as its backing file. + * Finds the image layer in the chain that has 'bs' (or a filter on + * top of it) as its backing file. * * active is the current topmost image. * @@ -4273,11 +4274,18 @@ int bdrv_change_backing_file(BlockDriverState *bs= , BlockDriverState *bdrv_find_overlay(BlockDriverState *active, BlockDriverState *bs) { - while (active && bs !=3D backing_bs(active)) { - active =3D backing_bs(active); + bs =3D bdrv_skip_rw_filters(bs); + active =3D bdrv_skip_rw_filters(active); + + while (active) { + BlockDriverState *next =3D bdrv_backing_chain_next(active); + if (bs =3D=3D next) { + return active; + } + active =3D next; } =20 - return active; + return NULL; } =20 /* Given a BDS, searches for the base layer. */ @@ -4421,9 +4429,7 @@ int bdrv_drop_intermediate(BlockDriverState *top, B= lockDriverState *base, * other intermediate nodes have been dropped. * If 'top' is an implicit node (e.g. "commit_top") we should skip * it because no one inherits from it. We use explicit_top for that.= */ - while (explicit_top && explicit_top->implicit) { - explicit_top =3D backing_bs(explicit_top); - } + explicit_top =3D bdrv_skip_implicit_filters(explicit_top); update_inherits_from =3D bdrv_inherits_from_recursive(base, explicit= _top); =20 /* success - we can delete the intermediate states, and link top->ba= se */ @@ -4902,7 +4908,7 @@ BlockDriverState *bdrv_lookup_bs(const char *device= , bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base) { while (top && top !=3D base) { - top =3D backing_bs(top); + top =3D bdrv_filtered_bs(top); } =20 return top !=3D NULL; @@ -5141,7 +5147,17 @@ BlockDriverState *bdrv_find_backing_image(BlockDri= verState *bs, =20 is_protocol =3D path_has_protocol(backing_file); =20 - for (curr_bs =3D bs; curr_bs->backing; curr_bs =3D curr_bs->backing-= >bs) { + /* + * Being largely a legacy function, skip any filters here + * (because filters do not have normal filenames, so they cannot + * match anyway; and allowing json:{} filenames is a bit out of + * scope). + */ + for (curr_bs =3D bdrv_skip_rw_filters(bs); + bdrv_filtered_cow_child(curr_bs) !=3D NULL; + curr_bs =3D bdrv_backing_chain_next(curr_bs)) + { + BlockDriverState *bs_below =3D bdrv_backing_chain_next(curr_bs); =20 /* If either of the filename paths is actually a protocol, then * compare unmodified paths; otherwise make paths relative */ @@ -5149,7 +5165,7 @@ BlockDriverState *bdrv_find_backing_image(BlockDriv= erState *bs, char *backing_file_full_ret; =20 if (strcmp(backing_file, curr_bs->backing_file) =3D=3D 0) { - retval =3D curr_bs->backing->bs; + retval =3D bs_below; break; } /* Also check against the full backing filename for the imag= e */ @@ -5159,7 +5175,7 @@ BlockDriverState *bdrv_find_backing_image(BlockDriv= erState *bs, bool equal =3D strcmp(backing_file, backing_file_full_re= t) =3D=3D 0; g_free(backing_file_full_ret); if (equal) { - retval =3D curr_bs->backing->bs; + retval =3D bs_below; break; } } @@ -5185,7 +5201,7 @@ BlockDriverState *bdrv_find_backing_image(BlockDriv= erState *bs, g_free(filename_tmp); =20 if (strcmp(backing_file_full, filename_full) =3D=3D 0) { - retval =3D curr_bs->backing->bs; + retval =3D bs_below; break; } } --=20 2.21.0