From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E38BC3A5A2 for ; Fri, 23 Aug 2019 14:48:43 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 126732166E for ; Fri, 23 Aug 2019 14:48:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 126732166E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57270 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i1Arp-00075q-W1 for qemu-devel@archiver.kernel.org; Fri, 23 Aug 2019 10:48:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51454) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i1AhG-00046Z-1X for qemu-devel@nongnu.org; Fri, 23 Aug 2019 10:37:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i1AhE-0004jc-RL for qemu-devel@nongnu.org; Fri, 23 Aug 2019 10:37:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54338) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i1AhB-0004eH-Un; Fri, 23 Aug 2019 10:37:42 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CFDC718C8910; Fri, 23 Aug 2019 14:37:36 +0000 (UTC) Received: from blue.redhat.com (ovpn-116-234.phx2.redhat.com [10.3.116.234]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6FB126CE58; Fri, 23 Aug 2019 14:37:36 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Fri, 23 Aug 2019 09:37:25 -0500 Message-Id: <20190823143726.27062-5-eblake@redhat.com> In-Reply-To: <20190823143726.27062-1-eblake@redhat.com> References: <25ead363-4f37-5450-b985-1876374e314d@redhat.com> <20190823143726.27062-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.70]); Fri, 23 Aug 2019 14:37:36 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 4/5] nbd: Implement server use of NBD FAST_ZERO X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:Network Block Dev..." , libguestfs@redhat.com, nbd@other.debian.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The server side is fairly straightforward: we can always advertise support for detection of fast zero, and implement it by mapping the request to the block layer BDRV_REQ_NO_FALLBACK. Signed-off-by: Eric Blake --- Again, this may be worth merging with the previous patch. --- nbd/server.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index 981bc3cb1151..3c0799eda87f 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1514,7 +1514,8 @@ NBDExport *nbd_export_new(BlockDriverState *bs, uin= t64_t dev_offset, exp->nbdflags |=3D NBD_FLAG_CAN_MULTI_CONN; } } else { - exp->nbdflags |=3D NBD_FLAG_SEND_TRIM | NBD_FLAG_SEND_WRITE_ZERO= ES; + exp->nbdflags |=3D (NBD_FLAG_SEND_TRIM | NBD_FLAG_SEND_WRITE_ZER= OES | + NBD_FLAG_SEND_FAST_ZERO); } assert(size <=3D INT64_MAX - dev_offset); exp->size =3D QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE); @@ -2167,7 +2168,7 @@ static int nbd_co_receive_request(NBDRequestData *r= eq, NBDRequest *request, if (request->type =3D=3D NBD_CMD_READ && client->structured_reply) { valid_flags |=3D NBD_CMD_FLAG_DF; } else if (request->type =3D=3D NBD_CMD_WRITE_ZEROES) { - valid_flags |=3D NBD_CMD_FLAG_NO_HOLE; + valid_flags |=3D NBD_CMD_FLAG_NO_HOLE | NBD_CMD_FLAG_FAST_ZERO; } else if (request->type =3D=3D NBD_CMD_BLOCK_STATUS) { valid_flags |=3D NBD_CMD_FLAG_REQ_ONE; } @@ -2306,6 +2307,9 @@ static coroutine_fn int nbd_handle_request(NBDClien= t *client, if (!(request->flags & NBD_CMD_FLAG_NO_HOLE)) { flags |=3D BDRV_REQ_MAY_UNMAP; } + if (request->flags & NBD_CMD_FLAG_FAST_ZERO) { + flags |=3D BDRV_REQ_NO_FALLBACK; + } ret =3D blk_pwrite_zeroes(exp->blk, request->from + exp->dev_off= set, request->len, flags); return nbd_send_generic_reply(client, request->handle, ret, --=20 2.21.0