From nobody Sun Oct 5 21:01:02 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 1499289382803275.58468296905005; Wed, 5 Jul 2017 14:16:22 -0700 (PDT) Received: from localhost ([::1]:48091 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dSren-0002kj-5Q for importer@patchew.org; Wed, 05 Jul 2017 17:16:21 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37898) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dSrXs-0004v1-D3 for qemu-devel@nongnu.org; Wed, 05 Jul 2017 17:09:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dSrXn-0002ez-8g for qemu-devel@nongnu.org; Wed, 05 Jul 2017 17:09:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34918) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dSrXi-0002bg-5z; Wed, 05 Jul 2017 17:09:02 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 410A2C04D28B; Wed, 5 Jul 2017 21:09:01 +0000 (UTC) Received: from red.redhat.com (ovpn-120-36.rdu2.redhat.com [10.10.120.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id 219AE600CC; Wed, 5 Jul 2017 21:09:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 410A2C04D28B Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=eblake@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 410A2C04D28B From: Eric Blake To: qemu-devel@nongnu.org Date: Wed, 5 Jul 2017 16:08:26 -0500 Message-Id: <20170705210842.960-6-eblake@redhat.com> In-Reply-To: <20170705210842.960-1-eblake@redhat.com> References: <20170705210842.960-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Wed, 05 Jul 2017 21:09:01 +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 v4 05/21] stream: Switch stream_run() to byte-based 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, jcody@redhat.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" We are gradually converting to byte-based interfaces, as they are easier to reason about than sector-based. Change the internal loop iteration of streaming to track by bytes instead of sectors (although we are still guaranteed that we iterate by steps that are sector-aligned). Signed-off-by: Eric Blake Reviewed-by: John Snow Reviewed-by: Jeff Cody Reviewed-by: Kevin Wolf --- v4: avoid reached_end change by rebasing to earlier changes [Kevin], R-b ke= pt v2-v3: no change --- block/stream.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/block/stream.c b/block/stream.c index 12f1659..e3dd2ac 100644 --- a/block/stream.c +++ b/block/stream.c @@ -107,12 +107,11 @@ static void coroutine_fn stream_run(void *opaque) BlockBackend *blk =3D s->common.blk; BlockDriverState *bs =3D blk_bs(blk); BlockDriverState *base =3D s->base; - int64_t sector_num =3D 0; - int64_t end =3D -1; + int64_t offset =3D 0; uint64_t delay_ns =3D 0; int error =3D 0; int ret =3D 0; - int n =3D 0; + int n =3D 0; /* sectors */ void *buf; if (!bs->backing) { @@ -125,7 +124,6 @@ static void coroutine_fn stream_run(void *opaque) goto out; } - end =3D s->common.len >> BDRV_SECTOR_BITS; buf =3D qemu_blockalign(bs, STREAM_BUFFER_SIZE); /* Turn on copy-on-read for the whole block device so that guest read @@ -137,7 +135,7 @@ static void coroutine_fn stream_run(void *opaque) bdrv_enable_copy_on_read(bs); } - for (sector_num =3D 0; sector_num < end; sector_num +=3D n) { + for ( ; offset < s->common.len; offset +=3D n * BDRV_SECTOR_SIZE) { bool copy; /* Note that even when no rate limit is applied we need to yield @@ -150,28 +148,26 @@ static void coroutine_fn stream_run(void *opaque) copy =3D false; - ret =3D bdrv_is_allocated(bs, sector_num, + ret =3D bdrv_is_allocated(bs, offset / BDRV_SECTOR_SIZE, STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n); if (ret =3D=3D 1) { /* Allocated in the top, no need to copy. */ } else if (ret >=3D 0) { /* Copy if allocated in the intermediate images. Limit to the - * known-unallocated area [sector_num, sector_num+n). */ + * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE).= */ ret =3D bdrv_is_allocated_above(backing_bs(bs), base, - sector_num, n, &n); + offset / BDRV_SECTOR_SIZE, n, &n= ); /* Finish early if end of backing file has been reached */ if (ret =3D=3D 0 && n =3D=3D 0) { - n =3D end - sector_num; + n =3D (s->common.len - offset) / BDRV_SECTOR_SIZE; } copy =3D (ret =3D=3D 1); } - trace_stream_one_iteration(s, sector_num * BDRV_SECTOR_SIZE, - n * BDRV_SECTOR_SIZE, ret); + trace_stream_one_iteration(s, offset, n * BDRV_SECTOR_SIZE, ret); if (copy) { - ret =3D stream_populate(blk, sector_num * BDRV_SECTOR_SIZE, - n * BDRV_SECTOR_SIZE, buf); + ret =3D stream_populate(blk, offset, n * BDRV_SECTOR_SIZE, buf= ); } if (ret < 0) { BlockErrorAction action =3D --=20 2.9.4