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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 1EA44C04AB7 for ; Tue, 14 May 2019 23:43:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F084F2084E for ; Tue, 14 May 2019 23:43:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726792AbfENXnI (ORCPT ); Tue, 14 May 2019 19:43:08 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48776 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726369AbfENXm6 (ORCPT ); Tue, 14 May 2019 19:42:58 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4ENLvC7139829 for ; Tue, 14 May 2019 19:42:57 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2sg46gyqrv-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 14 May 2019 19:42:56 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 15 May 2019 00:42:53 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x4ENgqrU54132962 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 14 May 2019 23:42:52 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E5F2AAE053; Tue, 14 May 2019 23:42:51 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D2FDBAE051; Tue, 14 May 2019 23:42:51 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Tue, 14 May 2019 23:42:51 +0000 (GMT) Received: by tuxmaker.boeblingen.de.ibm.com (Postfix, from userid 4958) id 3C2E7E1954; Wed, 15 May 2019 01:42:51 +0200 (CEST) From: Eric Farman To: Cornelia Huck , Farhan Ali Cc: Halil Pasic , Pierre Morel , linux-s390@vger.kernel.org, kvm@vger.kernel.org, Eric Farman Subject: [PATCH v2 7/7] s390/cio: Remove vfio-ccw checks of command codes Date: Wed, 15 May 2019 01:42:48 +0200 X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190514234248.36203-1-farman@linux.ibm.com> References: <20190514234248.36203-1-farman@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 19051423-0012-0000-0000-0000031BB7C3 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19051423-0013-0000-0000-000021545248 Message-Id: <20190514234248.36203-8-farman@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-14_13:,, 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-1905140153 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org If the CCW being processed is a No-Operation, then by definition no data is being transferred. Let's fold those checks into the normal CCW processors, rather than skipping out early. Likewise, if the CCW being processed is a "test" (an invented definition to simply mean it ends in a zero), let's permit that to go through to the hardware. There's nothing inherently unique about those command codes versus one that ends in an eight [1], or any other otherwise valid command codes that are undefined for the device type in question. [1] POPS states that a x08 is a TIC CCW, and that having any high-order bits enabled is invalid for format-1 CCWs. For format-0 CCWs, the high-order bits are ignored. Signed-off-by: Eric Farman --- drivers/s390/cio/vfio_ccw_cp.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index 94888094ed2c..abe0f501a963 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -295,8 +295,6 @@ static long copy_ccw_from_iova(struct channel_program *cp, #define ccw_is_read_backward(_ccw) (((_ccw)->cmd_code & 0x0F) == 0x0C) #define ccw_is_sense(_ccw) (((_ccw)->cmd_code & 0x0F) == CCW_CMD_BASIC_SENSE) -#define ccw_is_test(_ccw) (((_ccw)->cmd_code & 0x0F) == 0) - #define ccw_is_noop(_ccw) ((_ccw)->cmd_code == CCW_CMD_NOOP) #define ccw_is_tic(_ccw) ((_ccw)->cmd_code == CCW_CMD_TIC) @@ -320,6 +318,10 @@ static inline int ccw_does_data_transfer(struct ccw1 *ccw) if (ccw->count == 0) return 0; + /* If the command is a NOP, then no data will be transferred */ + if (ccw_is_noop(ccw)) + return 0; + /* If the skip flag is off, then data will be transferred */ if (!ccw_is_skip(ccw)) return 1; @@ -404,7 +406,7 @@ static void ccwchain_cda_free(struct ccwchain *chain, int idx) { struct ccw1 *ccw = chain->ch_ccw + idx; - if (ccw_is_test(ccw) || ccw_is_noop(ccw) || ccw_is_tic(ccw)) + if (ccw_is_tic(ccw)) return; kfree((void *)(u64)ccw->cda); @@ -729,9 +731,6 @@ static int ccwchain_fetch_one(struct ccwchain *chain, { struct ccw1 *ccw = chain->ch_ccw + idx; - if (ccw_is_test(ccw) || ccw_is_noop(ccw)) - return 0; - if (ccw_is_tic(ccw)) return ccwchain_fetch_tic(chain, idx, cp); -- 2.17.1