From patchwork Thu Aug 18 16:46:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre Morel X-Patchwork-Id: 12947463 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 F3526C32772 for ; Thu, 18 Aug 2022 16:48:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345122AbiHRQsK (ORCPT ); Thu, 18 Aug 2022 12:48:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345081AbiHRQrw (ORCPT ); Thu, 18 Aug 2022 12:47:52 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7E44C6CE5; Thu, 18 Aug 2022 09:47:17 -0700 (PDT) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 27IGUkbX039666; Thu, 18 Aug 2022 16:47:00 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=bNhQF7m6NNjHwMbuXmobYlnCkDs6tJhGu9M+3GLpoKI=; b=TzVRCS6l+59NisBmBYLgZYNYcDE+9CArY/uBU1VapMqlFZja1/pU0aSYVOXm4es3zglG GMBjGHBhwPYzRPbkG6urtdjIhy4s1kj2mYH43ThoPPvQ9VdL4ARwD0Ti+4Y4bS7gpGTi sXwRHM0nsmLMmxc1/auBm53zVb74Mna7puooQOO49ZeUv7/G9L+6PrNWyZTAj5IZdzeq n2ZcCuj3h9IBVRZZWiAs9wc8HI2BNRMx3uWGmnLauX2xgE46I7Xwedn9ItQpJ4DryqgL dDpArkviSTOhkAnKvriLMW5QN71u1sTvKnv6XD9F+iMNWVnj6IW+rtmKJdzoZ+e35mEV Iw== 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 3j1s0vgfg8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Aug 2022 16:47:00 +0000 Received: from pps.filterd (ppma02fra.de.ibm.com [127.0.0.1]) by ppma02fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 27IGa8Vx030574; Thu, 18 Aug 2022 16:46:57 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma02fra.de.ibm.com with ESMTP id 3j0dc3a3cs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Aug 2022 16:46:57 +0000 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 27IGksiq33030552 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 18 Aug 2022 16:46:54 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F1086AE04D; Thu, 18 Aug 2022 16:46:53 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 588C4AE045; Thu, 18 Aug 2022 16:46:53 +0000 (GMT) Received: from li-c6ac47cc-293c-11b2-a85c-d421c8e4747b.ibm.com.com (unknown [9.171.73.125]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 18 Aug 2022 16:46:53 +0000 (GMT) From: Pierre Morel To: mjrosato@linux.ibm.com Cc: rdunlap@infradead.org, linux-kernel@vger.kernel.org, lkp@intel.com, borntraeger@linux.ibm.com, farman@linux.ibm.com, linux-s390@vger.kernel.org, kvm@vger.kernel.org, gor@linux.ibm.com, hca@linux.ibm.com, schnelle@linux.ibm.com, frankja@linux.ibm.com Subject: [PATCH] KVM: s390: pci: Hook to access KVM lowlevel from VFIO Date: Thu, 18 Aug 2022 18:46:52 +0200 Message-Id: <20220818164652.269336-1-pmorel@linux.ibm.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: -8qHxZrcUwfJJU_RTGIHHHYOGfOINJVQ X-Proofpoint-ORIG-GUID: -8qHxZrcUwfJJU_RTGIHHHYOGfOINJVQ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-08-18_12,2022-08-18_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=874 spamscore=0 mlxscore=0 malwarescore=0 phishscore=0 adultscore=0 priorityscore=1501 bulkscore=0 impostorscore=0 suspectscore=0 clxscore=1015 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2208180060 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org We have a cross dependency between KVM and VFIO when using s390 vfio_pci_zdev extensions for PCI passthrough To be able to keep both subsystem modular we add a registering hook inside the S390 core code. This fixes a build problem when VFIO is built-in and KVM is built as a module. Reported-by: Randy Dunlap Reported-by: kernel test robot Signed-off-by: Pierre Morel Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop inter..") Cc: Reviewed-by: Matthew Rosato Reviewed-by: Niklas Schnelle --- arch/s390/include/asm/kvm_host.h | 17 ++++++----------- arch/s390/kvm/pci.c | 10 ++++++---- arch/s390/pci/Makefile | 2 ++ arch/s390/pci/pci_kvm_hook.c | 11 +++++++++++ drivers/vfio/pci/vfio_pci_zdev.c | 8 ++++++-- 5 files changed, 31 insertions(+), 17 deletions(-) create mode 100644 arch/s390/pci/pci_kvm_hook.c diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index f39092e0ceaa..b1e98a9ed152 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -1038,16 +1038,11 @@ static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} #define __KVM_HAVE_ARCH_VM_FREE void kvm_arch_free_vm(struct kvm *kvm); -#ifdef CONFIG_VFIO_PCI_ZDEV_KVM -int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm); -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev); -#else -static inline int kvm_s390_pci_register_kvm(struct zpci_dev *dev, - struct kvm *kvm) -{ - return -EPERM; -} -static inline void kvm_s390_pci_unregister_kvm(struct zpci_dev *dev) {} -#endif +struct zpci_kvm_hook { + int (*kvm_register)(void *opaque, struct kvm *kvm); + void (*kvm_unregister)(void *opaque); +}; + +extern struct zpci_kvm_hook zpci_kvm_hook; #endif diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c index 4946fb7757d6..22c025538323 100644 --- a/arch/s390/kvm/pci.c +++ b/arch/s390/kvm/pci.c @@ -431,8 +431,9 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev) * available, enable them and let userspace indicate whether or not they will * be used (specify SHM bit to disable). */ -int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm) +static int kvm_s390_pci_register_kvm(void *opaque, struct kvm *kvm) { + struct zpci_dev *zdev = opaque; int rc; if (!zdev) @@ -510,10 +511,10 @@ int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm) kvm_put_kvm(kvm); return rc; } -EXPORT_SYMBOL_GPL(kvm_s390_pci_register_kvm); -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) +static void kvm_s390_pci_unregister_kvm(void *opaque) { + struct zpci_dev *zdev = opaque; struct kvm *kvm; if (!zdev) @@ -566,7 +567,6 @@ void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) kvm_put_kvm(kvm); } -EXPORT_SYMBOL_GPL(kvm_s390_pci_unregister_kvm); void kvm_s390_pci_init_list(struct kvm *kvm) { @@ -678,6 +678,8 @@ int kvm_s390_pci_init(void) spin_lock_init(&aift->gait_lock); mutex_init(&aift->aift_lock); + zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; + zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; return 0; } diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile index bf557a1b789c..c02dbfb415d9 100644 --- a/arch/s390/pci/Makefile +++ b/arch/s390/pci/Makefile @@ -7,3 +7,5 @@ obj-$(CONFIG_PCI) += pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \ pci_event.o pci_debug.o pci_insn.o pci_mmio.o \ pci_bus.o obj-$(CONFIG_PCI_IOV) += pci_iov.o + +obj-y += pci_kvm_hook.o diff --git a/arch/s390/pci/pci_kvm_hook.c b/arch/s390/pci/pci_kvm_hook.c new file mode 100644 index 000000000000..ff34baf50a3e --- /dev/null +++ b/arch/s390/pci/pci_kvm_hook.c @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VFIO ZPCI devices support + * + * Copyright (C) IBM Corp. 2022. All rights reserved. + * Author(s): Pierre Morel + */ +#include + +struct zpci_kvm_hook zpci_kvm_hook; +EXPORT_SYMBOL_GPL(zpci_kvm_hook); diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c index e163aa9f6144..0cbdcd14f1c8 100644 --- a/drivers/vfio/pci/vfio_pci_zdev.c +++ b/drivers/vfio/pci/vfio_pci_zdev.c @@ -151,7 +151,10 @@ int vfio_pci_zdev_open_device(struct vfio_pci_core_device *vdev) if (!vdev->vdev.kvm) return 0; - return kvm_s390_pci_register_kvm(zdev, vdev->vdev.kvm); + if (zpci_kvm_hook.kvm_register) + return zpci_kvm_hook.kvm_register(zdev, vdev->vdev.kvm); + + return -ENOENT; } void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) @@ -161,5 +164,6 @@ void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) if (!zdev || !vdev->vdev.kvm) return; - kvm_s390_pci_unregister_kvm(zdev); + if (zpci_kvm_hook.kvm_unregister) + zpci_kvm_hook.kvm_unregister(zdev); }