From nobody Mon Feb 9 15:11:18 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1499908568951421.35255200904396; Wed, 12 Jul 2017 18:16:08 -0700 (PDT) Received: from localhost ([::1]:56714 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dVSjd-0005n0-FY for importer@patchew.org; Wed, 12 Jul 2017 21:16:05 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37262) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dVSaQ-0005FG-GF for qemu-devel@nongnu.org; Wed, 12 Jul 2017 21:06:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dVSaP-0001t9-Gb for qemu-devel@nongnu.org; Wed, 12 Jul 2017 21:06:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55154) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dVSaM-0001px-Fp; Wed, 12 Jul 2017 21:06:30 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8467580480; Thu, 13 Jul 2017 01:06:29 +0000 (UTC) Received: from red.redhat.com (ovpn-121-60.rdu2.redhat.com [10.10.121.60]) by smtp.corp.redhat.com (Postfix) with ESMTP id 66ED06F960; Thu, 13 Jul 2017 01:06:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 8467580480 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=eblake@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 8467580480 From: Eric Blake To: qemu-devel@nongnu.org Date: Wed, 12 Jul 2017 20:05:51 -0500 Message-Id: <20170713010555.6769-15-eblake@redhat.com> In-Reply-To: <20170713010555.6769-1-eblake@redhat.com> References: <20170713010555.6769-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 13 Jul 2017 01:06:29 +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 v5 14/18] qcow2: Switch qcow2_measure() to byte-based iteration 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, vsementsov@virtuozzo.com, jsnow@redhat.com, qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This is new code, but it is easier to read if it makes passes over the image using bytes rather than sectors (and will get easier in the future when bdrv_get_block_status is converted to byte-based). While at it, fix a bug in the computation of nb_sectors using MAX rather than MIN and thus always passing INT_MAX (thankfully, the bug was harmless, as bdrv_get_block_status_above() clamps its answers according to image size). Signed-off-by: Eric Blake Reviewed-by: John Snow --- v5: new patch --- block/qcow2.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index c144ea5..85ee9b2 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3662,20 +3662,19 @@ static BlockMeasureInfo *qcow2_measure(QemuOpts *op= ts, BlockDriverState *in_bs, */ required =3D virtual_size; } else { - int cluster_sectors =3D cluster_size / BDRV_SECTOR_SIZE; - int64_t sector_num; + int64_t offset; int pnum =3D 0; - for (sector_num =3D 0; - sector_num < ssize / BDRV_SECTOR_SIZE; - sector_num +=3D pnum) { - int nb_sectors =3D MAX(ssize / BDRV_SECTOR_SIZE - sector_n= um, - INT_MAX); + for (offset =3D 0; offset < ssize; + offset +=3D pnum * BDRV_SECTOR_SIZE) { + int nb_sectors =3D MIN(ssize - offset, + INT_MAX) / BDRV_SECTOR_SIZE; BlockDriverState *file; int64_t ret; ret =3D bdrv_get_block_status_above(in_bs, NULL, - sector_num, nb_sectors, + offset >> BDRV_SECTOR_BI= TS, + nb_sectors, &pnum, &file); if (ret < 0) { error_setg_errno(&local_err, -ret, @@ -3688,12 +3687,11 @@ static BlockMeasureInfo *qcow2_measure(QemuOpts *op= ts, BlockDriverState *in_bs, } else if ((ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED)= ) =3D=3D (BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED)) { /* Extend pnum to end of cluster for next iteration */ - pnum =3D ROUND_UP(sector_num + pnum, cluster_sectors) - - sector_num; + pnum =3D (ROUND_UP(offset + pnum * BDRV_SECTOR_SIZE, + cluster_size) - offset) >> BDRV_SECTOR_BI= TS; /* Count clusters we've seen */ - required +=3D (sector_num % cluster_sectors + pnum) * - BDRV_SECTOR_SIZE; + required +=3D offset % cluster_size + pnum * BDRV_SECT= OR_SIZE; } } } --=20 2.9.4