From nobody Sun Oct 5 21:16:21 2025 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 1505761873446567.4368944099931; Mon, 18 Sep 2017 12:11:13 -0700 (PDT) Received: from localhost ([::1]:38427 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1du1Ro-0005aC-KF for importer@patchew.org; Mon, 18 Sep 2017 15:11:12 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44547) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1du1GF-0002aM-2o for qemu-devel@nongnu.org; Mon, 18 Sep 2017 14:59:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1du1GE-0006hn-32 for qemu-devel@nongnu.org; Mon, 18 Sep 2017 14:59:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51484) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1du1GB-0006fG-Ik; Mon, 18 Sep 2017 14:59:11 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7DA4946287; Mon, 18 Sep 2017 18:59:10 +0000 (UTC) Received: from red.redhat.com (ovpn-124-97.rdu2.redhat.com [10.10.124.97]) by smtp.corp.redhat.com (Postfix) with ESMTP id 648515C1A3; Mon, 18 Sep 2017 18:59:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 7DA4946287 Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=eblake@redhat.com From: Eric Blake To: qemu-devel@nongnu.org Date: Mon, 18 Sep 2017 13:58:15 -0500 Message-Id: <20170918185819.5984-17-eblake@redhat.com> In-Reply-To: <20170918185819.5984-1-eblake@redhat.com> References: <20170918185819.5984-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Mon, 18 Sep 2017 18:59:10 +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 v8 16/20] 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). Signed-off-by: Eric Blake Reviewed-by: John Snow --- v7: tweak constant given to MIN (no semantic change, R-b kept) [Kevin] v6: separate bug fix to earlier patch 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 bae5893327..64dcd98a91 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3647,20 +3647,19 @@ 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 MIN(ssize / BDRV_SECTOR_SIZE - sector_n= um, - BDRV_REQUEST_MAX_SECTORS); + for (offset =3D 0; offset < ssize; + offset +=3D pnum * BDRV_SECTOR_SIZE) { + int nb_sectors =3D MIN(ssize - offset, + BDRV_REQUEST_MAX_BYTES) / 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, @@ -3673,12 +3672,11 @@ 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 2.13.5