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=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 67132C11F65 for ; Wed, 30 Jun 2021 16:06:21 +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 C32C26141A for ; Wed, 30 Jun 2021 16:06:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C32C26141A 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]:44264 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lycjD-0007DA-Jr for qemu-devel@archiver.kernel.org; Wed, 30 Jun 2021 12:06:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43944) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lycfV-0002rO-Pw for qemu-devel@nongnu.org; Wed, 30 Jun 2021 12:02:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:54544) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lycfR-00070c-Qz for qemu-devel@nongnu.org; Wed, 30 Jun 2021 12:02:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625068945; 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=Gzkz4iQ1z7SgIx+HREwKK8edPLbz9y/BM8Rp8M8y6Tg=; b=hLlkYxzhybQnfPHS12ZtVjtGulM3/VOTqtzBa3QYZTWXtoCu92N6RD9Ew4AECNyMPqWv/h la7NF+0tEfYF0uNIXYlxzVYSLNG9BDyc/hbxpD05PXXonkg/OdDtbrnM6Ir8KCIr8AdlLn 9JfGxZKBbayIokXShXyNyPksRQhlGkU= 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-495-oSqTpHrMO9aqnBWm3CyIaA-1; Wed, 30 Jun 2021 12:02:21 -0400 X-MC-Unique: oSqTpHrMO9aqnBWm3CyIaA-1 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 2B4AF801596; Wed, 30 Jun 2021 16:02:20 +0000 (UTC) Received: from merkur.fritz.box (ovpn-114-114.ams2.redhat.com [10.36.114.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3977A189C7; Wed, 30 Jun 2021 16:02:19 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PULL 07/24] block: introduce bdrv_set_file_or_backing_noperm() Date: Wed, 30 Jun 2021 18:01:49 +0200 Message-Id: <20210630160206.276439-8-kwolf@redhat.com> In-Reply-To: <20210630160206.276439-1-kwolf@redhat.com> References: <20210630160206.276439-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.435, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vladimir Sementsov-Ogievskiy To be used for reopen in future commit. Notes: - It seems OK to update inherits_from if new bs is recursively inherits from parent bs. Let's just not check for backing_chain_contains, to support file child of non-filters. - Simply check child->frozen instead of bdrv_is_backing_chain_frozen(), as we really interested only in this one child. - Role determination of new child is a bit more complex: it remains the same for backing child, it's obvious for filter driver. But for non-filter file child let's for now restrict to only replacing existing child (and keeping its role). Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20210610120537.196183-3-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf --- block.c | 83 +++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 63 insertions(+), 20 deletions(-) diff --git a/block.c b/block.c index 7eceef0afa..14711ce7ab 100644 --- a/block.c +++ b/block.c @@ -84,6 +84,9 @@ static BlockDriverState *bdrv_open_inherit(const char *filename, static void bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs); +static void bdrv_remove_file_or_backing_child(BlockDriverState *bs, + BdrvChild *child, + Transaction *tran); static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs, Transaction *tran); @@ -3117,56 +3120,96 @@ static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) } /* - * Sets the bs->backing link of a BDS. A new reference is created; callers - * which don't need their own reference any more must call bdrv_unref(). + * Sets the bs->backing or bs->file link of a BDS. A new reference is created; + * callers which don't need their own reference any more must call bdrv_unref(). * * Function doesn't update permissions, caller is responsible for this. */ -static int bdrv_set_backing_noperm(BlockDriverState *bs, - BlockDriverState *backing_hd, - Transaction *tran, Error **errp) +static int bdrv_set_file_or_backing_noperm(BlockDriverState *parent_bs, + BlockDriverState *child_bs, + bool is_backing, + Transaction *tran, Error **errp) { int ret = 0; - bool update_inherits_from = bdrv_chain_contains(bs, backing_hd) && - bdrv_inherits_from_recursive(backing_hd, bs); + bool update_inherits_from = + bdrv_inherits_from_recursive(child_bs, parent_bs); + BdrvChild *child = is_backing ? parent_bs->backing : parent_bs->file; + BdrvChildRole role; - if (bdrv_is_backing_chain_frozen(bs, child_bs(bs->backing), errp)) { + if (!parent_bs->drv) { + /* + * Node without drv is an object without a class :/. TODO: finally fix + * qcow2 driver to never clear bs->drv and implement format corruption + * handling in other way. + */ + error_setg(errp, "Node corrupted"); + return -EINVAL; + } + + if (child && child->frozen) { + error_setg(errp, "Cannot change frozen '%s' link from '%s' to '%s'", + child->name, parent_bs->node_name, child->bs->node_name); return -EPERM; } - if (bs->backing) { - /* Cannot be frozen, we checked that above */ - bdrv_unset_inherits_from(bs, bs->backing, tran); - bdrv_remove_filter_or_cow_child(bs, tran); + if (parent_bs->drv->is_filter) { + role = BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; + } else if (is_backing) { + role = BDRV_CHILD_COW; + } else { + /* + * We only can use same role as it is in existing child. We don't have + * infrastructure to determine role of file child in generic way + */ + if (!child) { + error_setg(errp, "Cannot set file child to format node without " + "file child"); + return -EINVAL; + } + role = child->role; } - if (!backing_hd) { + if (child) { + bdrv_unset_inherits_from(parent_bs, child, tran); + bdrv_remove_file_or_backing_child(parent_bs, child, tran); + } + + if (!child_bs) { goto out; } - ret = bdrv_attach_child_noperm(bs, backing_hd, "backing", - &child_of_bds, bdrv_backing_role(bs), - &bs->backing, tran, errp); + ret = bdrv_attach_child_noperm(parent_bs, child_bs, + is_backing ? "backing" : "file", + &child_of_bds, role, + is_backing ? &parent_bs->backing : + &parent_bs->file, + tran, errp); if (ret < 0) { return ret; } /* - * If backing_hd was already part of bs's backing chain, and - * inherits_from pointed recursively to bs then let's update it to + * If inherits_from pointed recursively to bs then let's update it to * point directly to bs (else it will become NULL). */ if (update_inherits_from) { - bdrv_set_inherits_from(backing_hd, bs, tran); + bdrv_set_inherits_from(child_bs, parent_bs, tran); } out: - bdrv_refresh_limits(bs, tran, NULL); + bdrv_refresh_limits(parent_bs, tran, NULL); return 0; } +static int bdrv_set_backing_noperm(BlockDriverState *bs, + BlockDriverState *backing_hd, + Transaction *tran, Error **errp) +{ + return bdrv_set_file_or_backing_noperm(bs, backing_hd, true, tran, errp); +} + int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, Error **errp) { -- 2.31.1