From nobody Wed Apr 16 07:39:13 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 1499448387764766.2685790752411; Fri, 7 Jul 2017 10:26:27 -0700 (PDT) Received: from localhost ([::1]:57785 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dTX1O-0003Dp-F0 for importer@patchew.org; Fri, 07 Jul 2017 13:26:26 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41671) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dTWlB-0004zi-De for qemu-devel@nongnu.org; Fri, 07 Jul 2017 13:09:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dTWlA-0007si-BZ for qemu-devel@nongnu.org; Fri, 07 Jul 2017 13:09:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40026) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dTWl7-0007qW-Ub; Fri, 07 Jul 2017 13:09:38 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 016D2624A8; Fri, 7 Jul 2017 17:09:37 +0000 (UTC) Received: from noname.redhat.com (ovpn-117-34.ams2.redhat.com [10.36.117.34]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1A0DF61F23; Fri, 7 Jul 2017 17:09:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 016D2624A8 Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=kwolf@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 016D2624A8 From: Kevin Wolf To: qemu-block@nongnu.org Date: Fri, 7 Jul 2017 19:07:38 +0200 Message-Id: <1499447335-6125-24-git-send-email-kwolf@redhat.com> In-Reply-To: <1499447335-6125-1-git-send-email-kwolf@redhat.com> References: <1499447335-6125-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Fri, 07 Jul 2017 17:09:37 +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] [PULL 023/100] stream: Drop reached_end for stream_complete() 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, qemu-devel@nongnu.org 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" From: Eric Blake stream_complete() skips the work of rewriting the backing file if the job was cancelled, if data->reached_end is false, or if there was an error detected (non-zero data->ret) during the streaming. But note that in stream_run(), data->reached_end is only set if the loop ran to completion, and data->ret is only 0 in two cases: either the loop ran to completion (possibly by cancellation, but stream_complete checks for that), or we took an early goto out because there is no bs->backing. Thus, we can preserve the same semantics without the use of reached_end, by merely checking for bs->backing (and logically, if there was no backing file, streaming is a no-op, so there is no backing file to rewrite). Suggested-by: Kevin Wolf Signed-off-by: Eric Blake Reviewed-by: John Snow Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- block/stream.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/block/stream.c b/block/stream.c index 746d525..12f1659 100644 --- a/block/stream.c +++ b/block/stream.c @@ -59,7 +59,6 @@ static int coroutine_fn stream_populate(BlockBackend *blk, =20 typedef struct { int ret; - bool reached_end; } StreamCompleteData; =20 static void stream_complete(BlockJob *job, void *opaque) @@ -70,7 +69,7 @@ static void stream_complete(BlockJob *job, void *opaque) BlockDriverState *base =3D s->base; Error *local_err =3D NULL; =20 - if (!block_job_is_cancelled(&s->common) && data->reached_end && + if (!block_job_is_cancelled(&s->common) && bs->backing && data->ret =3D=3D 0) { const char *base_id =3D NULL, *base_fmt =3D NULL; if (base) { @@ -211,7 +210,6 @@ out: /* Modify backing chain and close BDSes in main loop */ data =3D g_malloc(sizeof(*data)); data->ret =3D ret; - data->reached_end =3D sector_num =3D=3D end; block_job_defer_to_main_loop(&s->common, stream_complete, data); } =20 --=20 1.8.3.1