From patchwork Fri May 15 15:15:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cornelia Huck X-Patchwork-Id: 11552415 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 98CF359D for ; Fri, 15 May 2020 15:16:34 +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 70F3220728 for ; Fri, 15 May 2020 15:16:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HdyJytwu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 70F3220728 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:53118 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jZc4f-0005pE-L7 for patchwork-qemu-devel@patchwork.kernel.org; Fri, 15 May 2020 11:16:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50326) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jZc3k-0004AV-1J for qemu-devel@nongnu.org; Fri, 15 May 2020 11:15:36 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:56587 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jZc3i-0005za-FP for qemu-devel@nongnu.org; Fri, 15 May 2020 11:15:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589555733; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6pddmoRnqZoHNeMB0r0PyY5bEn79vipDG8JOISd/tkc=; b=HdyJytwuilSXYazWi6lzCdMm3YMh+5MFfWDcs4HZCXKhUVRkxHomos7WBUsDZRIU3TDa6z JCZ27lrSgskjzbgyprSAepmaOCYQJr1r5q3mwpb0tE1d3tuFzs52VHXof/WkyPxFlVwOBo YeXYQrwsT/4BXCBlOvKXKpWMqLUqcuc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-145-sD3zGBhyOdOS50vKX5ha2Q-1; Fri, 15 May 2020 11:15:31 -0400 X-MC-Unique: sD3zGBhyOdOS50vKX5ha2Q-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id DBEF68735C8; Fri, 15 May 2020 15:15:30 +0000 (UTC) Received: from localhost (ovpn-112-229.ams2.redhat.com [10.36.112.229]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 420E06E9E5; Fri, 15 May 2020 15:15:30 +0000 (UTC) From: Cornelia Huck To: qemu-s390x@nongnu.org Subject: [PATCH v2 3/3] docs/s390x: document vfio-ccw Date: Fri, 15 May 2020 17:15:18 +0200 Message-Id: <20200515151518.83950-4-cohuck@redhat.com> In-Reply-To: <20200515151518.83950-1-cohuck@redhat.com> References: <20200515151518.83950-1-cohuck@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=cohuck@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/14 22:56:02 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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: Thomas Huth , Cornelia Huck , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Add a basic example for passing a dasd via vfio-ccw. Signed-off-by: Cornelia Huck --- docs/system/s390x/vfio-ccw.rst | 72 ++++++++++++++++++++++++++++++++++ docs/system/target-s390x.rst | 1 + 2 files changed, 73 insertions(+) create mode 100644 docs/system/s390x/vfio-ccw.rst diff --git a/docs/system/s390x/vfio-ccw.rst b/docs/system/s390x/vfio-ccw.rst new file mode 100644 index 000000000000..4cfd22c3b789 --- /dev/null +++ b/docs/system/s390x/vfio-ccw.rst @@ -0,0 +1,72 @@ +Subchannel passthrough via vfio-ccw +=================================== + +vfio-ccw (based upon the mediated vfio device infrastructure) allows to +make certain I/O subchannels and their devices available to a guest. The +host will not interact with those subchannels/devices any more. + +Note that while vfio-ccw should work with most non-QDIO devices, only ECKD +DASDs have really been tested. + +Example configuration +--------------------- + +Step 1: configure the host device +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Note: it is recommended to use the ``mdevctl`` tool for this step. + +To define the same device as configured below to be started +automatically, use + +:: + + [root@host ~]# driverctl -b css set-override 0.0.0313 vfio_ccw + [root@host ~]# mdevctl define -u 7e270a25-e163-4922-af60-757fc8ed48c6\ + -p 0.0.0313 -t vfio-ccw_io -a + +If this is not possible or wanted, follow the manual procedure below. + +* Locate the subchannel for the device (in this example, ``0.0.2b09``):: + + [root@host ~]# lscss | grep 0.0.2b09 | awk '{print $2}' + 0.0.0313 + +* Unbind the subchannel (in this example, ``0.0.0313``) from the standard + I/O subchannel driver and bind it to the vfio-ccw driver:: + + [root@host ~]# echo 0.0.0313 > /sys/bus/css/devices/0.0.0313/driver/unbind + [root@host ~]# echo 0.0.0313 > /sys/bus/css/drivers/vfio_ccw/bind + +* Create the mediated device (identified by a uuid):: + + [root@host ~]# uuidgen + 7e270a25-e163-4922-af60-757fc8ed48c6 + [root@host ~]# echo "7e270a25-e163-4922-af60-757fc8ed48c6" > \ + /sys/bus/css/devices/0.0.0313/mdev_supported_types/vfio_ccw-io/create + +Step 2: configure QEMU +~~~~~~~~~~~~~~~~~~~~~~ + +* Reference the created mediated device and (optionally) pick a device id to + be presented in the guest (here, ``fe.0.1234``, which will end up visible + in the guest as ``0.0.1234``:: + + -device vfio-ccw,devno=fe.0.1234,sysfsdev=\ + /sys/bus/mdev/devices/7e270a25-e163-4922-af60-757fc8ed48c6 + +* Start the guest. The device (here, ``0.0.1234``) should now be usable:: + + [root@guest ~]# lscss -d 0.0.1234 + Device Subchan. DevType CU Type Use PIM PAM POM CHPIDs + ---------------------------------------------------------------------- + 0.0.1234 0.0.0007 3390/0e 3990/e9 f0 f0 ff 1a2a3a0a 00000000 + [root@guest ~]# chccwdev -e 0.0.1234 + Setting device 0.0.1234 online + Done + [root@guest ~]# dmesg -t + (...) + dasd-eckd 0.0.1234: A channel path to the device has become operational + dasd-eckd 0.0.1234: New DASD 3390/0E (CU 3990/01) with 10017 cylinders, 15 heads, 224 sectors + dasd-eckd 0.0.1234: DASD with 4 KB/block, 7212240 KB total size, 48 KB/track, compatible disk layout + dasda:VOL1/ 0X2B09: dasda1 diff --git a/docs/system/target-s390x.rst b/docs/system/target-s390x.rst index 2592a05303ef..644e404ef9fd 100644 --- a/docs/system/target-s390x.rst +++ b/docs/system/target-s390x.rst @@ -25,6 +25,7 @@ or vfio-ap is also available. s390x/vfio-ap s390x/css s390x/3270 + s390x/vfio-ccw Architectural features ======================