From patchwork Mon May 25 18:08:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alberto Garcia X-Patchwork-Id: 1297505 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=igalia.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=QY6LIkS+; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 49W4zf4Lzjz9sRW for ; Tue, 26 May 2020 04:16:30 +1000 (AEST) Received: from localhost ([::1]:39216 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jdHeG-0006JX-4v for incoming@patchwork.ozlabs.org; Mon, 25 May 2020 14:16:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45228) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jdHXs-0003xb-O3; Mon, 25 May 2020 14:09:52 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:50992) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jdHXq-0007pf-2W; Mon, 25 May 2020 14:09:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=Oe86ilax3C8jctFM722sy6VnDUpDOutRe3DDBEhiVz4=; b=QY6LIkS+kqitLscv5WV1Z8J+dlpTv9FbMlUS2a5Vt+NpBVLmMooAZVyghjmzrN0lhjmw8wJRTneBWPBO34RaG3qihoy97Z6lCp/hhHl/Uu5kW+AUFkZrvoOCtP6UcfWRsqqLTIcbdwDVgZ1AVh5BiwrvsSHBckKkW6K9EuAcIQK4PLDKXxU2mrNAEtvw8niAkH2g41uhy/SzOF4qBpeUcZig/yQomTvHHytLKaxDMkUHR03XjUAjAdtVBhShXTVndkKlglG+vKOncw6uxr++NlPNN7Tby4D+CyG6qkcgCPpC8pmLlD3pYr/XzhEhzbwTDJG1gQFnJVeLD07GfIIvzg==; Received: from [81.0.38.199] (helo=perseus.local) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim) id 1jdHXP-00088l-FL; Mon, 25 May 2020 20:09:23 +0200 Received: from berto by perseus.local with local (Exim 4.92) (envelope-from ) id 1jdHXA-0002Nq-Fo; Mon, 25 May 2020 20:09:08 +0200 From: Alberto Garcia To: qemu-devel@nongnu.org Subject: [PATCH v7 31/32] qcow2: Assert that expand_zero_clusters_in_l1() does not support subclusters Date: Mon, 25 May 2020 20:08:56 +0200 Message-Id: <46c7f6775d80ad10d791c94cf49e402858466b58.1590429902.git.berto@igalia.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=178.60.130.6; envelope-from=berto@igalia.com; helo=fanzine.igalia.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/25 14:09:23 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x (no timestamps) [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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN 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 , Vladimir Sementsov-Ogievskiy , Alberto Garcia , qemu-block@nongnu.org, Derek Su , Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This function is only used by qcow2_expand_zero_clusters() to downgrade a qcow2 image to a previous version. It is however not possible to downgrade an image with extended L2 entries because older versions of qcow2 do not have this feature. Signed-off-by: Alberto Garcia Reviewed-by: Eric Blake --- block/qcow2-cluster.c | 8 +++++++- tests/qemu-iotests/061 | 6 ++++++ tests/qemu-iotests/061.out | 5 +++++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 1641976028..2ceeb22f29 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -2157,6 +2157,9 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, int ret; int i, j; + /* qcow2_downgrade() is not allowed in images with subclusters */ + assert(!has_subclusters(s)); + slice_size2 = s->l2_slice_size * l2_entry_size(s); n_slices = s->cluster_size / slice_size2; @@ -2225,7 +2228,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) { if (!bs->backing) { /* not backed; therefore we can simply deallocate the - * cluster */ + * cluster. No need to call set_l2_bitmap(), this + * function doesn't support images with subclusters. */ set_l2_entry(s, l2_slice, j, 0); l2_dirty = true; continue; @@ -2296,6 +2300,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, } else { set_l2_entry(s, l2_slice, j, offset); } + /* No need to call set_l2_bitmap() after set_l2_entry() because + * this function doesn't support images with subclusters. */ l2_dirty = true; } diff --git a/tests/qemu-iotests/061 b/tests/qemu-iotests/061 index 10eb243164..23add2dfe3 100755 --- a/tests/qemu-iotests/061 +++ b/tests/qemu-iotests/061 @@ -303,6 +303,12 @@ $QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" _img_info --format-specific _check_test_img +echo +echo "=== Testing version downgrade with extended L2 entries ===" +echo +_make_test_img -o "compat=1.1,extended_l2=on" 64M +$QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" + echo echo "=== Try changing the external data file ===" echo diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out index 39812d8cf8..c1acdbd751 100644 --- a/tests/qemu-iotests/061.out +++ b/tests/qemu-iotests/061.out @@ -528,6 +528,11 @@ Format specific information: extended l2: false No errors were found on the image. +=== Testing version downgrade with extended L2 entries === + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 +qemu-img: Cannot downgrade an image with incompatible features 0x10 set + === Try changing the external data file === Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864