From patchwork Fri Nov 18 11:01:48 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jike Song X-Patchwork-Id: 9436213 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6163C60755 for ; Fri, 18 Nov 2016 11:09:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 47915290CD for ; Fri, 18 Nov 2016 11:09:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3C925293E8; Fri, 18 Nov 2016 11:09:00 +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=-6.9 required=2.0 tests=BAYES_00,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 C25CA29146 for ; Fri, 18 Nov 2016 11:08:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752553AbcKRLI4 (ORCPT ); Fri, 18 Nov 2016 06:08:56 -0500 Received: from mga02.intel.com ([134.134.136.20]:15171 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752401AbcKRLIx (ORCPT ); Fri, 18 Nov 2016 06:08:53 -0500 Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP; 18 Nov 2016 03:08:51 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,509,1473145200"; d="scan'208";a="32827486" Received: from kvmgt1.bj.intel.com ([10.238.154.158]) by fmsmga005.fm.intel.com with ESMTP; 18 Nov 2016 03:08:49 -0800 From: Jike Song To: alex.williamson@redhat.com, pbonzini@redhat.com, guangrong.xiao@linux.intel.com Cc: kwankhede@nvidia.com, cjia@nvidia.com, kevin.tian@intel.com, jike.song@intel.com, kvm@vger.kernel.org Subject: [v6 2/3] vfio: support notifier chain in vfio_group Date: Fri, 18 Nov 2016 19:01:48 +0800 Message-Id: <1479466909-31765-3-git-send-email-jike.song@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1479466909-31765-1-git-send-email-jike.song@intel.com> References: <1479466909-31765-1-git-send-email-jike.song@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Beyond vfio_iommu events, users might also be interested in vfio_group events. For example, if a vfio_group is used along with Qemu/KVM, whenever kvm pointer is set to/cleared from the vfio_group, users could be notified. Currently only VFIO_GROUP_NOTIFY_SET_KVM supported. Cc: Alex Williamson Cc: Kirti Wankhede Cc: Paolo Bonzini Cc: Xiao Guangrong Signed-off-by: Jike Song --- drivers/vfio/vfio.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/vfio.h | 6 +++++ 2 files changed, 75 insertions(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index ec62bec..e2bb197 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -86,6 +86,8 @@ struct vfio_group { struct mutex unbound_lock; atomic_t opened; bool noiommu; + struct kvm *kvm; + struct blocking_notifier_head notifier; }; struct vfio_device { @@ -339,6 +341,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group) #ifdef CONFIG_VFIO_NOIOMMU group->noiommu = (iommu_group_get_iommudata(iommu_group) == &noiommu); #endif + BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier); group->nb.notifier_call = vfio_iommu_group_notifier; @@ -1015,6 +1018,63 @@ static long vfio_ioctl_check_extension(struct vfio_container *container, return ret; } +void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) +{ + group->kvm = kvm; + blocking_notifier_call_chain(&group->notifier, + VFIO_GROUP_NOTIFY_SET_KVM, kvm); +} +EXPORT_SYMBOL_GPL(vfio_group_set_kvm); + +static int vfio_register_group_notifier(struct vfio_group *group, + unsigned long *events, + struct notifier_block *nb) +{ + int ret; + bool set_kvm = false; + + if (*events & VFIO_GROUP_NOTIFY_SET_KVM) + set_kvm = true; + + /* clear known events */ + *events &= ~VFIO_GROUP_NOTIFY_SET_KVM; + + /* refuse to continue if still events remaining */ + if (*events) + return -EINVAL; + + if (!atomic_inc_not_zero(&group->opened)) + return -EINVAL; + + ret = blocking_notifier_chain_register(&group->notifier, nb); + + /* + * The attaching of kvm and vfio_group might already happen, so + * here we replay once upon registration. + */ + if (!ret && set_kvm && group->kvm) + blocking_notifier_call_chain(&group->notifier, + VFIO_GROUP_NOTIFY_SET_KVM, group->kvm); + + atomic_dec(&group->opened); + + return ret; +} + +static int vfio_unregister_group_notifier(struct vfio_group *group, + struct notifier_block *nb) +{ + int ret; + + if (!atomic_inc_not_zero(&group->opened)) + return -EINVAL; + + ret = blocking_notifier_chain_unregister(&group->notifier, nb); + + atomic_dec(&group->opened); + return ret; +} + /* hold write lock on container->group_lock */ static int __vfio_container_attach_groups(struct vfio_container *container, struct vfio_iommu_driver *driver, @@ -1581,6 +1641,9 @@ static int vfio_group_fops_release(struct inode *inode, struct file *filep) filep->private_data = NULL; + /* Any user didn't unregister? */ + WARN_ON(group->notifier.head); + vfio_group_try_dissolve_container(group); atomic_dec(&group->opened); @@ -2088,6 +2151,9 @@ int vfio_register_notifier(struct device *dev, vfio_notify_type_t type, case VFIO_IOMMU_NOTIFY: ret = vfio_register_iommu_notifier(group, events, nb); break; + case VFIO_GROUP_NOTIFY: + ret = vfio_register_group_notifier(group, events, nb); + break; default: ret = EINVAL; } @@ -2114,6 +2180,9 @@ int vfio_unregister_notifier(struct device *dev, vfio_notify_type_t type, case VFIO_IOMMU_NOTIFY: ret = vfio_unregister_iommu_notifier(group, nb); break; + case VFIO_GROUP_NOTIFY: + ret = vfio_unregister_group_notifier(group, nb); + break; default: ret = -EINVAL; } diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 6f3ff31..5d46e3c 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -119,11 +119,17 @@ extern int vfio_unregister_notifier(struct device *dev, /* each type has independent events */ enum vfio_notify_type { VFIO_IOMMU_NOTIFY = (__force vfio_notify_type_t)0, + VFIO_GROUP_NOTIFY = (__force vfio_notify_type_t)1, }; /* events for VFIO_IOMMU_NOTIFY */ #define VFIO_IOMMU_NOTIFY_DMA_UNMAP BIT(0) +/* events for VFIO_GROUP_NOTIFY */ +#define VFIO_GROUP_NOTIFY_SET_KVM BIT(0) + +struct kvm; +extern void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm); /* * Sub-module helpers