From patchwork Fri Jun 24 08:18:17 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Feiran Zheng X-Patchwork-Id: 101738 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 5AD6DB6F87 for ; Fri, 24 Jun 2011 18:24:05 +1000 (EST) Received: from localhost ([::1]:38566 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa1gH-0006S7-4m for incoming@patchwork.ozlabs.org; Fri, 24 Jun 2011 04:24:01 -0400 Received: from eggs.gnu.org ([140.186.70.92]:54130) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa1cY-0006JH-AC for qemu-devel@nongnu.org; Fri, 24 Jun 2011 04:20:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qa1cW-0001of-OA for qemu-devel@nongnu.org; Fri, 24 Jun 2011 04:20:10 -0400 Received: from mail-iy0-f173.google.com ([209.85.210.173]:63570) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa1cW-0001ms-Dt for qemu-devel@nongnu.org; Fri, 24 Jun 2011 04:20:08 -0400 Received: by mail-iy0-f173.google.com with SMTP id 3so2656746iyb.4 for ; Fri, 24 Jun 2011 01:20:08 -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=KWbBT4jmCpYBpDHBAj4q2+9ODQnEwjNlbLfEEIihJCE=; b=PN5vglrV3luyLxWpjp3T6NCTXj0kS8OOzkB7jrxgMqxcZT4G6V3JP3+GDf/GgwbYxo 3wh4pcBTtHWfrsR0meh7kf/lDWzoPCAPUUEqmSIaQEPuaZoAjrUQQNJQmawdp/P1gLhk oc1o3mMUABywld4rlS/cPjCALAL1SjV30WyRo= 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=G4G6B6TycBERY1Dz2c94a1p9WPZiRAK4yTy4i0SeyPNCuHQ2PZhbclrhIAlcfhO1SI DJPFFJeCVTW03OHIx4jqVOtYruME/E1fuWjswsqcW4pjFzKoJIelkWrKoQcPITayG6yu MddIOKv1pNRoNzxefJgdmUS5xl/ZniG7W+tvA= Received: by 10.231.92.196 with SMTP id s4mr2689595ibm.10.1308903608193; Fri, 24 Jun 2011 01:20:08 -0700 (PDT) Received: from localhost.localdomain (admis.tongji.edu.cn [202.120.189.202]) by mx.google.com with ESMTPS id f19sm1351912ibl.66.2011.06.24.01.20.05 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 24 Jun 2011 01:20:07 -0700 (PDT) From: famcool@gmail.com To: qemu-devel@nongnu.org Date: Fri, 24 Jun 2011 16:18:17 +0800 Message-Id: <1308903507-10799-3-git-send-email-famcool@gmail.com> X-Mailer: git-send-email 1.7.5.2 In-Reply-To: <1308903507-10799-1-git-send-email-famcool@gmail.com> References: <1308903507-10799-1-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 v2 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 From: Fam Zheng 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 c7246f0..0540ec5 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -485,21 +485,23 @@ 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) {