From patchwork Wed Sep 1 15:15:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 12469655 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 CD831C4320E for ; Wed, 1 Sep 2021 15:43:24 +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 86A4960FDC for ; Wed, 1 Sep 2021 15:43:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 86A4960FDC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:60352 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mLSOZ-00088j-J1 for qemu-devel@archiver.kernel.org; Wed, 01 Sep 2021 11:43:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50102) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mLRzr-0005vu-FB for qemu-devel@nongnu.org; Wed, 01 Sep 2021 11:17:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:54456) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mLRzc-0003zy-0H for qemu-devel@nongnu.org; Wed, 01 Sep 2021 11:17:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1630509455; 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=9OIJu2C6R8G1A7dgQhlDuoWRimyYxMU47fUlvcQm6qw=; b=DLB0UKpvWdfmcYrLszNGJTajo/e/hjn+L3TI5+EF67ySwge2f2z6i5j8orZfcUEq8pWsRY lcu7ePczYP3iaUeobVw/kxzJRbKS8+VnyyHPaYiXrO6XqVDesdeDGhHBbmV/RbgWTg2usI 7+dHtnS5a5mnpJ1qJKfuVp8YdXt1bQA= 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-526-1hc-Q8kZPlqPScDGMPoDEQ-1; Wed, 01 Sep 2021 11:17:34 -0400 X-MC-Unique: 1hc-Q8kZPlqPScDGMPoDEQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3DBD31B2C986; Wed, 1 Sep 2021 15:17:33 +0000 (UTC) Received: from localhost (unknown [10.39.193.250]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C9A8160C05; Wed, 1 Sep 2021 15:17:32 +0000 (UTC) From: Hanna Reitz To: qemu-block@nongnu.org Subject: [PULL 33/56] block/copy-before-write: bdrv_cbw_append(): replace child at last Date: Wed, 1 Sep 2021 17:15:56 +0200 Message-Id: <20210901151619.689075-34-hreitz@redhat.com> In-Reply-To: <20210901151619.689075-1-hreitz@redhat.com> References: <20210901151619.689075-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=hreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.392, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, 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 , Peter Maydell , Hanna Reitz , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vladimir Sementsov-Ogievskiy Refactor the function to replace child at last. Thus we don't need to revert it and code is simplified. block-copy state initialization being done before replacing the child doesn't need any drained section. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Max Reitz Message-Id: <20210824083856.17408-14-vsementsov@virtuozzo.com> Signed-off-by: Hanna Reitz --- block/copy-before-write.c | 33 +++++++++++---------------------- 1 file changed, 11 insertions(+), 22 deletions(-) diff --git a/block/copy-before-write.c b/block/copy-before-write.c index 7a6c15f141..adbbc64aa9 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -172,7 +172,6 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, int ret; BDRVCopyBeforeWriteState *state; BlockDriverState *top; - bool appended = false; assert(source->total_sectors == target->total_sectors); @@ -196,8 +195,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, BDRV_CHILD_DATA, errp); if (!state->target) { error_prepend(errp, "Cannot attach target child: "); - bdrv_unref(top); - return NULL; + goto fail; } bdrv_ref(source); @@ -206,18 +204,8 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, errp); if (!top->file) { error_prepend(errp, "Cannot attach file child: "); - bdrv_unref(top); - return NULL; - } - - bdrv_drained_begin(source); - - ret = bdrv_replace_node(source, top, errp); - if (ret < 0) { - error_prepend(errp, "Cannot append copy-before-write filter: "); goto fail; } - appended = true; state->bcs = block_copy_state_new(top->file, state->target, false, compress, errp); @@ -225,21 +213,22 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, error_prepend(errp, "Cannot create block-copy-state: "); goto fail; } - *bcs = state->bcs; + bdrv_drained_begin(source); + ret = bdrv_replace_node(source, top, errp); bdrv_drained_end(source); + if (ret < 0) { + error_prepend(errp, "Cannot append copy-before-write filter: "); + goto fail; + } + + *bcs = state->bcs; return top; fail: - if (appended) { - bdrv_cbw_drop(top); - } else { - bdrv_unref(top); - } - - bdrv_drained_end(source); - + block_copy_state_free(state->bcs); + bdrv_unref(top); return NULL; }