From patchwork Mon Feb 6 16:45:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Janis Schoetterl-Glausch X-Patchwork-Id: 13130366 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 393A6C64EC3 for ; Mon, 6 Feb 2023 16:46:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230465AbjBFQq0 (ORCPT ); Mon, 6 Feb 2023 11:46:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230324AbjBFQqU (ORCPT ); Mon, 6 Feb 2023 11:46:20 -0500 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54DA125E2A; Mon, 6 Feb 2023 08:46:19 -0800 (PST) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 316GjLkE027846; Mon, 6 Feb 2023 16:46:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=C40ZJntMyqrcalxbNSfEu9RUVWoSIhODXs0/a6CxYlc=; b=Rc0zKPJzgPCBFo265T973kBjzGAGS+lnjtpFmHVY9lYkVoC06TwK6pWOpglvqiKsB6H9 c9OzKufUQToOURaukReaPfyg0LKk7/P0ClSm5fuagolV05ROX3R6bpsyw8uczGCLd2iR 35AuDEWsIrn8RKeXAExktAoBHzHtSl46S55qeXoWyBCcDwEylrSC0SWIy+TaJPUTbGWo LmzQ/4lY2cl7FjXARIb2oBnpVol7fW/qC9ChvtxYyXJwl8JETdooaA6SfRVg6r5o60Jo VLvX+C2YlNnkZdRsN6Idakhxw9OJg/H0p/WyHrf2yVuGVDnP3N/6/HuGAdb2DKT6ndZe ww== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3nk3rmbf4j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Feb 2023 16:46:15 +0000 Received: from m0098417.ppops.net (m0098417.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 316GjdrB028960; Mon, 6 Feb 2023 16:46:14 GMT Received: from ppma02fra.de.ibm.com (47.49.7a9f.ip4.static.sl-reverse.com [159.122.73.71]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3nk3rmbf3n-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Feb 2023 16:46:14 +0000 Received: from pps.filterd (ppma02fra.de.ibm.com [127.0.0.1]) by ppma02fra.de.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 315DvivH005516; Mon, 6 Feb 2023 16:46:12 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma02fra.de.ibm.com (PPS) with ESMTPS id 3nhf06sv6x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Feb 2023 16:46:12 +0000 Received: from smtpav01.fra02v.mail.ibm.com (smtpav01.fra02v.mail.ibm.com [10.20.54.100]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 316Gk90e42992040 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 6 Feb 2023 16:46:09 GMT Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 12C1420040; Mon, 6 Feb 2023 16:46:09 +0000 (GMT) Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 94F7120043; Mon, 6 Feb 2023 16:46:08 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by smtpav01.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 6 Feb 2023 16:46:08 +0000 (GMT) From: Janis Schoetterl-Glausch To: Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Heiko Carstens , Vasily Gorbik , Alexander Gordeev Cc: Janis Schoetterl-Glausch , David Hildenbrand , Jonathan Corbet , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, Paolo Bonzini , Shuah Khan , Sven Schnelle , Thomas Huth Subject: [PATCH v7 09/14] KVM: s390: Dispatch to implementing function at top level of vm mem_op Date: Mon, 6 Feb 2023 17:45:57 +0100 Message-Id: <20230206164602.138068-10-scgl@linux.ibm.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20230206164602.138068-1-scgl@linux.ibm.com> References: <20230206164602.138068-1-scgl@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: vQp4nn4U6iMn9Qok-aC0yQMF2tSTaTjs X-Proofpoint-ORIG-GUID: OvX0vlJCrIW_TkW8ooRU44VPX8ev3V-r X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.930,Hydra:6.0.562,FMLib:17.11.122.1 definitions=2023-02-06_07,2023-02-06_03,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 priorityscore=1501 spamscore=0 malwarescore=0 clxscore=1015 bulkscore=0 adultscore=0 mlxscore=0 impostorscore=0 phishscore=0 suspectscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2302060144 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Instead of having one function covering all mem_op operations, have a function implementing absolute access and dispatch to that function in its caller, based on the operation code. This way additional future operations can be implemented by adding an implementing function without changing existing operations. Suggested-by: Janosch Frank Signed-off-by: Janis Schoetterl-Glausch Reviewed-by: Thomas Huth Reviewed-by: Janosch Frank --- arch/s390/kvm/kvm-s390.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 0367c1a7e69a..707967a296f1 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2779,7 +2779,7 @@ static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_fla return 0; } -static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) +static int kvm_s390_vm_mem_op_abs(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; void *tmpbuf = NULL; @@ -2790,17 +2790,6 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) if (r) return r; - /* - * This is technically a heuristic only, if the kvm->lock is not - * taken, it is not guaranteed that the vm is/remains non-protected. - * This is ok from a kernel perspective, wrongdoing is detected - * on the access, -EFAULT is returned and the vm may crash the - * next time it accesses the memory in question. - * There is no sane usecase to do switching and a memop on two - * different CPUs at the same time. - */ - if (kvm_s390_pv_get_handle(kvm)) - return -EINVAL; if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { tmpbuf = vmalloc(mop->size); if (!tmpbuf) @@ -2841,8 +2830,6 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) } break; } - default: - r = -EINVAL; } out_unlock: @@ -2852,6 +2839,29 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) return r; } +static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) +{ + /* + * This is technically a heuristic only, if the kvm->lock is not + * taken, it is not guaranteed that the vm is/remains non-protected. + * This is ok from a kernel perspective, wrongdoing is detected + * on the access, -EFAULT is returned and the vm may crash the + * next time it accesses the memory in question. + * There is no sane usecase to do switching and a memop on two + * different CPUs at the same time. + */ + if (kvm_s390_pv_get_handle(kvm)) + return -EINVAL; + + switch (mop->op) { + case KVM_S390_MEMOP_ABSOLUTE_READ: + case KVM_S390_MEMOP_ABSOLUTE_WRITE: + return kvm_s390_vm_mem_op_abs(kvm, mop); + default: + return -EINVAL; + } +} + long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) {