From patchwork Tue Jun 28 01:32:47 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Feiran Zheng X-Patchwork-Id: 102305 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 8D328B6F6F for ; Tue, 28 Jun 2011 11:55:53 +1000 (EST) Received: from localhost ([::1]:57140 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QbNWm-0007tj-Vr for incoming@patchwork.ozlabs.org; Mon, 27 Jun 2011 21:55:49 -0400 Received: from eggs.gnu.org ([140.186.70.92]:57515) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QbNBG-00037e-PQ for qemu-devel@nongnu.org; Mon, 27 Jun 2011 21:33:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QbNBE-0004L8-Td for qemu-devel@nongnu.org; Mon, 27 Jun 2011 21:33:34 -0400 Received: from mail-iy0-f173.google.com ([209.85.210.173]:37108) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QbNBE-0004Jh-Cd for qemu-devel@nongnu.org; Mon, 27 Jun 2011 21:33:32 -0400 Received: by mail-iy0-f173.google.com with SMTP id 3so5589872iyb.4 for ; Mon, 27 Jun 2011 18:33:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:from:to:cc:subject:date:message-id:x-mailer :in-reply-to:references; bh=C2ACLU2a57tm6WQ4kqc9us73dvad9FM+v+/VWJkuxoQ=; b=ct4B+3qc15qQrl5NuEFvzCKzQKIHWFsEKni6/XiAHGlObL9j/uqKnFpBOthcizR+2y DQgi4ZBNjRCtTD9LAifkoCcSi42qHkeKlJczAGc0aibR3VgGw1mR1csFTJEJDgAyBt1m psk0/7Ty/Kj8p69dxSJo/9lempaH7szj9rOcU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=b4Ah5vB2bfxzRci/9xafPLEML5gm8zpO8QkAuQbjgc+XaGWNZOLVpEvb4hoxghGLAw BWCD57lKb3SW0o2SdMWI20KM8OiuprGE/P4hqMd3R6WpDBATe34RATuTEZAB9sgYwnJw 08HnQ2Wp5iqXvvzVJWPVk6PzerRWTbzoHMouI= Received: by 10.231.116.86 with SMTP id l22mr4710342ibq.56.1309224811671; Mon, 27 Jun 2011 18:33:31 -0700 (PDT) Received: from localhost.localdomain ([111.187.42.58]) by mx.google.com with ESMTPS id p15sm3341784ibh.12.2011.06.27.18.33.28 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 27 Jun 2011 18:33:31 -0700 (PDT) From: Fam Zheng To: qemu-devel@nongnu.org Date: Tue, 28 Jun 2011 09:32:47 +0800 Message-Id: <1309224777-31024-3-git-send-email-famcool@gmail.com> X-Mailer: git-send-email 1.7.5.2 In-Reply-To: <1309224777-31024-1-git-send-email-famcool@gmail.com> References: <1309224777-31024-1-git-send-email-famcool@gmail.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) X-Received-From: 209.85.210.173 Cc: kwolf@redhat.com, Fam Zheng , hch@lst.de, stefanha@gmail.com Subject: [Qemu-devel] [PATCH v5 02/12] VMDK: bugfix, align offset to cluster in get_whole_cluster X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org In get_whole_cluster, the offset is not aligned to cluster when reading from backing_hd. When the first write to child is not at the cluster boundary, wrong address data from parent is copied to child. Signed-off-by: Fam Zheng --- block/vmdk.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 49df1a5..a2538be 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -511,21 +511,23 @@ static int get_whole_cluster(BlockDriverState *bs, /* 128 sectors * 512 bytes each = grain size 64KB */ uint8_t whole_grain[extent->cluster_sectors * 512]; - // we will be here if it's first write on non-exist grain(cluster). - // try to read from parent image, if exist + /* we will be here if it's first write on non-exist grain(cluster). + * try to read from parent image, if exist */ if (bs->backing_hd) { int ret; if (!vmdk_is_cid_valid(bs)) return -1; + /* floor offset to cluster */ + offset -= offset % (extent->cluster_sectors * 512); ret = bdrv_read(bs->backing_hd, offset >> 9, whole_grain, extent->cluster_sectors); if (ret < 0) { return -1; } - //Write grain only into the active image + /* Write grain only into the active image */ ret = bdrv_write(extent->file, cluster_offset, whole_grain, extent->cluster_sectors); if (ret < 0) {