From patchwork Thu Jul 11 14:28:51 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Farhan Ali X-Patchwork-Id: 11040143 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E029E1395 for ; Thu, 11 Jul 2019 14:29:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D06CB28ABE for ; Thu, 11 Jul 2019 14:29:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C500428AD1; Thu, 11 Jul 2019 14:29:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6F19F28ABE for ; Thu, 11 Jul 2019 14:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728525AbfGKO3D (ORCPT ); Thu, 11 Jul 2019 10:29:03 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45076 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728669AbfGKO3B (ORCPT ); Thu, 11 Jul 2019 10:29:01 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x6BESvVx056983; Thu, 11 Jul 2019 10:28:59 -0400 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0b-001b2d01.pphosted.com with ESMTP id 2tp5y5b0g5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 11 Jul 2019 10:28:58 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x6BEPDMt021920; Thu, 11 Jul 2019 14:28:58 GMT Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by ppma03dal.us.ibm.com with ESMTP id 2tjk974nh3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 11 Jul 2019 14:28:58 +0000 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x6BESu2l47186276 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 11 Jul 2019 14:28:56 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1975FAC060; Thu, 11 Jul 2019 14:28:56 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EF40CAC064; Thu, 11 Jul 2019 14:28:55 +0000 (GMT) Received: from alifm-ThinkPad-T470p.ibm.com (unknown [9.85.180.152]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTPS; Thu, 11 Jul 2019 14:28:55 +0000 (GMT) From: Farhan Ali To: cohuck@redhat.com, farman@linux.ibm.com, pasic@linux.ibm.com Cc: linux-s390@vger.kernel.org, kvm@vger.kernel.org, alifm@linux.ibm.com Subject: [PATCH v3 1/5] vfio-ccw: Fix misleading comment when setting orb.cmd.c64 Date: Thu, 11 Jul 2019 10:28:51 -0400 Message-Id: X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-07-11_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1907110163 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The comment is misleading because it tells us that we should set orb.cmd.c64 before calling ccwchain_calc_length, otherwise the function ccwchain_calc_length would return an error. This is not completely accurate. We want to allow an orb without cmd.c64, and this is fine as long as the channel program does not use IDALs. But we do want to reject any channel program that uses IDALs and does not set the flag, which is what we do in ccwchain_calc_length. After we have done the ccw processing, we need to set cmd.c64, as we use IDALs for all translated channel programs. Also for better code readability let's move the setting of cmd.c64 within the non error path. Signed-off-by: Farhan Ali Reviewed-by: Cornelia Huck Reviewed-by: Eric Farman --- drivers/s390/cio/vfio_ccw_cp.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index d6a8dff..c969d48 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -645,14 +645,15 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb) if (ret) cp_free(cp); - /* It is safe to force: if not set but idals used - * ccwchain_calc_length returns an error. - */ - cp->orb.cmd.c64 = 1; - - if (!ret) + if (!ret) { cp->initialized = true; + /* It is safe to force: if it was not set but idals used + * ccwchain_calc_length would have returned an error. + */ + cp->orb.cmd.c64 = 1; + } + return ret; }