From patchwork Thu Apr 27 01:46:19 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 9702261 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D9B14601D3 for ; Thu, 27 Apr 2017 01:48:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CAD70285F8 for ; Thu, 27 Apr 2017 01:48:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BFC5828602; Thu, 27 Apr 2017 01:48:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 70E72285F8 for ; Thu, 27 Apr 2017 01:48:37 +0000 (UTC) Received: from localhost ([::1]:57791 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3YXs-00081b-Kp for patchwork-qemu-devel@patchwork.kernel.org; Wed, 26 Apr 2017 21:48:36 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33755) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3YW6-0007c3-Il for qemu-devel@nongnu.org; Wed, 26 Apr 2017 21:46:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d3YW5-00049V-3U for qemu-devel@nongnu.org; Wed, 26 Apr 2017 21:46:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40136) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d3YW0-00045J-ES; Wed, 26 Apr 2017 21:46:40 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 66E8167EAD; Thu, 27 Apr 2017 01:46:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 66E8167EAD Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=eblake@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 66E8167EAD Received: from red.redhat.com (ovpn-123-177.rdu2.redhat.com [10.10.123.177]) by smtp.corp.redhat.com (Postfix) with ESMTP id AB07418114; Thu, 27 Apr 2017 01:46:38 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Wed, 26 Apr 2017 20:46:19 -0500 Message-Id: <20170427014626.11553-11-eblake@redhat.com> In-Reply-To: <20170427014626.11553-1-eblake@redhat.com> References: <20170427014626.11553-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 27 Apr 2017 01:46:39 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v10 10/17] qcow2: Assert that cluster operations are aligned X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP We already audited (in commit 0c1bd469) that qcow2_discard_clusters() is only passed cluster-aligned start values; but we can further tighten the assertion that the only unaligned end value is at EOF. Recent commits have taken advantage of an unaligned tail cluster, for both discard and write zeroes. Signed-off-by: Eric Blake Reviewed-by: Max Reitz --- v10: rebase to context v9: rebase to master, by asserting that only tail cluster is unaligned v7, v8: only earlier half of series submitted for 2.9 v6: avoid assertion on non-cluster-aligned image, use s->cluster_sectors to avoid a shift, drop R-b v5: no change v4: new patch --- block/qcow2-cluster.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index d542894..4f641a9 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1572,11 +1572,10 @@ int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset, end_offset = offset + (nb_sectors << BDRV_SECTOR_BITS); - /* The caller must cluster-align start; round end down except at EOF */ + /* Caller must pass aligned values, except at image end */ assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); - if (end_offset != bs->total_sectors * BDRV_SECTOR_SIZE) { - end_offset = start_of_cluster(s, end_offset); - } + assert(QEMU_IS_ALIGNED(end_offset, s->cluster_size) || + end_offset == bs->total_sectors << BDRV_SECTOR_BITS); nb_clusters = size_to_clusters(s, end_offset - offset); @@ -1657,9 +1656,17 @@ int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors, int flags) { BDRVQcow2State *s = bs->opaque; + uint64_t end_offset; uint64_t nb_clusters; int ret; + end_offset = offset + (nb_sectors << BDRV_SECTOR_BITS); + + /* Caller must pass aligned values, except at image end */ + assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); + assert(QEMU_IS_ALIGNED(end_offset, s->cluster_size) || + end_offset == bs->total_sectors << BDRV_SECTOR_BITS); + /* The zero flag is only supported by version 3 and newer */ if (s->qcow_version < 3) { return -ENOTSUP;