From nobody Tue Nov 4 18:52:30 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; dmarc=fail(p=none dis=none) header.from=virtuozzo.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1530641361027803.8435665862805; Tue, 3 Jul 2018 11:09:21 -0700 (PDT) Received: from localhost ([::1]:42036 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1faPjr-0005DM-SR for importer@patchew.org; Tue, 03 Jul 2018 14:09:19 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41385) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1faPiZ-0004XK-4d for qemu-devel@nongnu.org; Tue, 03 Jul 2018 14:08:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1faPiV-0006TZ-5k for qemu-devel@nongnu.org; Tue, 03 Jul 2018 14:07:59 -0400 Received: from relay.sw.ru ([185.231.240.75]:34458) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1faPiU-0006QZ-Ta; Tue, 03 Jul 2018 14:07:55 -0400 Received: from vz-out.virtuozzo.com ([185.231.240.5] helo=kvm.sw.ru) by relay.sw.ru with esmtp (Exim 4.90_1) (envelope-from ) id 1faPiR-0001la-Ff; Tue, 03 Jul 2018 21:07:51 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-devel@nongnu.org, qemu-block@nongnu.org Date: Tue, 3 Jul 2018 21:07:50 +0300 Message-Id: <20180703180751.243496-2-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20180703180751.243496-1-vsementsov@virtuozzo.com> References: <20180703180751.243496-1-vsementsov@virtuozzo.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 185.231.240.75 Subject: [Qemu-devel] [PATCH 1/2] block: add BDRV_REQ_SERIALISING flag 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, famz@redhat.com, jsnow@redhat.com, jcody@redhat.com, mreitz@redhat.com, stefanha@redhat.com, den@openvz.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" Serialized writes should be used in copy-on-write of backup(sync=3Dnone) for image fleecing scheme. Signed-off-by: Vladimir Sementsov-Ogievskiy --- include/block/block.h | 5 ++++- block/io.c | 4 ++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/include/block/block.h b/include/block/block.h index e5c7759a0c..107113aad5 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -58,8 +58,11 @@ typedef enum { * content. */ BDRV_REQ_WRITE_UNCHANGED =3D 0x40, =20 + /* Force request serializing. Only for writes. */ + BDRV_REQ_SERIALISING =3D 0x80, + /* Mask of valid flags */ - BDRV_REQ_MASK =3D 0x7f, + BDRV_REQ_MASK =3D 0xff, } BdrvRequestFlags; =20 typedef struct BlockSizes { diff --git a/block/io.c b/block/io.c index 1a2272fad3..d5ba078514 100644 --- a/block/io.c +++ b/block/io.c @@ -1572,6 +1572,10 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChi= ld *child, max_transfer =3D QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_transfer, INT= _MAX), align); =20 + if (flags & BDRV_REQ_SERIALISING) { + mark_request_serialising(req, bdrv_get_cluster_size(bs)); + } + waited =3D wait_serialising_requests(req); assert(!waited || !req->serialising); assert(req->overlap_offset <=3D offset); --=20 2.11.1