From patchwork Mon Jul 18 09:27:54 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 649464 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3rtJTy4DgDz9s3v for ; Mon, 18 Jul 2016 19:56:22 +1000 (AEST) Received: from localhost ([::1]:45527 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bP5Hg-0005Ot-Gx for incoming@patchwork.ozlabs.org; Mon, 18 Jul 2016 05:56:20 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36442) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bP4qw-0004yO-KQ for qemu-devel@nongnu.org; Mon, 18 Jul 2016 05:28:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bP4qu-0006fL-Lt for qemu-devel@nongnu.org; Mon, 18 Jul 2016 05:28:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49596) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bP4qu-0006fB-Gs; Mon, 18 Jul 2016 05:28:40 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 223FD64D17; Mon, 18 Jul 2016 09:28:40 +0000 (UTC) Received: from donizetti.redhat.com (ovpn-112-56.ams2.redhat.com [10.36.112.56]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u6I9RuJH025611; Mon, 18 Jul 2016 05:28:38 -0400 From: Paolo Bonzini To: qemu-devel@nongnu.org Date: Mon, 18 Jul 2016 11:27:54 +0200 Message-Id: <1468834075-25669-23-git-send-email-pbonzini@redhat.com> In-Reply-To: <1468834075-25669-1-git-send-email-pbonzini@redhat.com> References: <1468834075-25669-1-git-send-email-pbonzini@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Mon, 18 Jul 2016 09:28:40 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 22/23] block/iscsi: fix rounding in iscsi_allocationmap_set 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: Peter Lieven , qemu-stable@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Peter Lieven when setting clusters as alloacted the boundaries have to be expanded. As Paolo pointed out the calculation of the number of clusters is wrong: Suppose cluster_sectors is 2, sector_num = 1, nb_sectors = 6: In the "mark allocated" case, you want to set 0..8, i.e. cluster_num=0, nb_clusters=4. 0--.--2--.--4--.--6--.--8 <--|_________________|--> (<--> = expanded) Instead you are setting nb_clusters=3, so that 6..8 is not marked. 0--.--2--.--4--.--6--.--8 <--|______________|!!! (! = wrong) Cc: qemu-stable@nongnu.org Reported-by: Paolo Bonzini Signed-off-by: Peter Lieven Message-Id: <1468831940-15556-2-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini --- block/iscsi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/block/iscsi.c b/block/iscsi.c index cf1e9e7..22330e1 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -432,12 +432,14 @@ static unsigned long *iscsi_allocationmap_init(IscsiLun *iscsilun) static void iscsi_allocationmap_set(IscsiLun *iscsilun, int64_t sector_num, int nb_sectors) { + int64_t cluster_num, nb_clusters; if (iscsilun->allocationmap == NULL) { return; } - bitmap_set(iscsilun->allocationmap, - sector_num / iscsilun->cluster_sectors, - DIV_ROUND_UP(nb_sectors, iscsilun->cluster_sectors)); + cluster_num = sector_num / iscsilun->cluster_sectors; + nb_clusters = DIV_ROUND_UP(sector_num + nb_sectors, + iscsilun->cluster_sectors) - cluster_num; + bitmap_set(iscsilun->allocationmap, cluster_num, nb_clusters); } static void iscsi_allocationmap_clear(IscsiLun *iscsilun, int64_t sector_num,