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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 A98B9C04A6B for ; Wed, 8 May 2019 09:14:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 746C520656 for ; Wed, 8 May 2019 09:14:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 746C520656 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 ([127.0.0.1]:33683 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hOIeS-0003zv-Ma for qemu-devel@archiver.kernel.org; Wed, 08 May 2019 05:14:12 -0400 Received: from eggs.gnu.org ([209.51.188.92]:45640) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hOIci-000329-PT for qemu-devel@nongnu.org; Wed, 08 May 2019 05:12:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hOIch-0004g9-Re for qemu-devel@nongnu.org; Wed, 08 May 2019 05:12:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38786) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hOIch-0004fr-Jv; Wed, 08 May 2019 05:12:23 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E1523308793E; Wed, 8 May 2019 09:12:22 +0000 (UTC) Received: from localhost (ovpn-204-161.brq.redhat.com [10.40.204.161]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5BF27611C3; Wed, 8 May 2019 09:12:22 +0000 (UTC) From: Cornelia Huck To: Halil Pasic , Christian Borntraeger Date: Wed, 8 May 2019 11:12:19 +0200 Message-Id: <20190508091219.13799-1-cohuck@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Wed, 08 May 2019 09:12:23 +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 RFC v3] s390/css: handle CCW_FLAG_SKIP 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: Eric Farman , qemu-s390x@nongnu.org, Cornelia Huck , qemu-devel@nongnu.org, Pierre Morel Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" If a ccw has CCW_FLAG_SKIP set, and the command is of type read, read backwards, or sense, no data should be written to the guest for that command. Signed-off-by: Cornelia Huck --- v2 -> v3: fixed checks even more [Pierre] v1 -> v2: fixed checks for command type [Eric] --- hw/s390x/css.c | 22 ++++++++++++++++++---- include/hw/s390x/css.h | 1 + 2 files changed, 19 insertions(+), 4 deletions(-) diff --git a/hw/s390x/css.c b/hw/s390x/css.c index 8fc9e35ba5d3..0fbaa233ffb5 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -830,8 +830,12 @@ static int ccw_dstream_rw_noflags(CcwDataStream *cds= , void *buff, int len, if (op =3D=3D CDS_OP_A) { goto incr; } - ret =3D address_space_rw(&address_space_memory, cds->cda, - MEMTXATTRS_UNSPECIFIED, buff, len, op); + if (!cds->do_skip) { + ret =3D address_space_rw(&address_space_memory, cds->cda, + MEMTXATTRS_UNSPECIFIED, buff, len, op); + } else { + ret =3D 0; + } if (ret !=3D MEMTX_OK) { cds->flags |=3D CDS_F_STREAM_BROKEN; return -EINVAL; @@ -928,8 +932,13 @@ static int ccw_dstream_rw_ida(CcwDataStream *cds, vo= id *buff, int len, do { iter_len =3D MIN(len, cont_left); if (op !=3D CDS_OP_A) { - ret =3D address_space_rw(&address_space_memory, cds->cda, - MEMTXATTRS_UNSPECIFIED, buff, iter_le= n, op); + if (!cds->do_skip) { + ret =3D address_space_rw(&address_space_memory, cds->cda= , + MEMTXATTRS_UNSPECIFIED, buff, ite= r_len, + op); + } else { + ret =3D 0; + } if (ret !=3D MEMTX_OK) { /* assume inaccessible address */ ret =3D -EINVAL; /* channel program check */ @@ -968,6 +977,11 @@ void ccw_dstream_init(CcwDataStream *cds, CCW1 const= *ccw, ORB const *orb) =20 cds->count =3D ccw->count; cds->cda_orig =3D ccw->cda; + /* skip is only effective for read, read backwards, or sense command= s */ + cds->do_skip =3D (ccw->flags & CCW_FLAG_SKIP) && + ((ccw->cmd_code & 0x0f) =3D=3D CCW_CMD_BASIC_SENSE || + (ccw->cmd_code & 0x03) =3D=3D 0x02 /* read */ || + (ccw->cmd_code & 0x0f) =3D=3D 0x0c /* read backwards */); ccw_dstream_rewind(cds); if (!(cds->flags & CDS_F_IDA)) { cds->op_handler =3D ccw_dstream_rw_noflags; diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h index aae19c427229..7cc183ef4366 100644 --- a/include/hw/s390x/css.h +++ b/include/hw/s390x/css.h @@ -97,6 +97,7 @@ typedef struct CcwDataStream { int (*op_handler)(struct CcwDataStream *cds, void *buff, int len, CcwDataStreamOp op); hwaddr cda; + bool do_skip; } CcwDataStream; =20 /* --=20 2.20.1