From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jike Song Subject: [v4 1/3] vfio: add vfio_group_notify support Date: Tue, 15 Nov 2016 19:35:45 +0800 Message-ID: <1479209747-5564-2-git-send-email-jike.song@intel.com> References: <1479209747-5564-1-git-send-email-jike.song@intel.com> Cc: kwankhede@nvidia.com, cjia@nvidia.com, kevin.tian@intel.com, kvm@vger.kernel.org, jike.song@intel.com To: alex.williamson@redhat.com, pbonzini@redhat.com, guangrong.xiao@linux.intel.com Return-path: Received: from mga09.intel.com ([134.134.136.24]:6706 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752603AbcKOLma (ORCPT ); Tue, 15 Nov 2016 06:42:30 -0500 In-Reply-To: <1479209747-5564-1-git-send-email-jike.song@intel.com> Sender: kvm-owner@vger.kernel.org List-ID: A vfio_group may be or may not be attached to a KVM instance, if it is, the user of vfio_group might also want to know which KVM instance it is attached to, and when it will detach. In VFIO there are already external APIs for KVM to get/put vfio_group, by providing a similar vfio_group_notify, KVM can notify the vfio_group about attaching events. Cc: Xiao Guangrong Cc: Paolo Bonzini Cc: Alex Williamson Signed-off-by: Jike Song --- drivers/vfio/vfio.c | 30 ++++++++++++++++++++++++++++++ include/linux/vfio.h | 4 ++++ 2 files changed, 34 insertions(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 0afb58e..b149ced 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 { @@ -1015,6 +1017,34 @@ static long vfio_ioctl_check_extension(struct vfio_container *container, return ret; } +void vfio_group_notify(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_notify); + +static void vfio_group_register_notifier(struct vfio_group *group, + struct notifier_block *nb) +{ + blocking_notifier_chain_register(&group->notifier, nb); + + /* + * The attaching of kvm and vfio_group might already happen, so + * here we replay once on registration. + */ + if (group->kvm) + blocking_notifier_call_chain(&group->notifier, + VFIO_GROUP_NOTIFY_SET_KVM, group->kvm); +} + +static void vfio_group_unregister_notifier(struct vfio_group *group, + struct notifier_block *nb) +{ + blocking_notifier_chain_unregister(&group->notifier, nb); +} + /* hold write lock on container->group_lock */ static int __vfio_container_attach_groups(struct vfio_container *container, struct vfio_iommu_driver *driver, diff --git a/include/linux/vfio.h b/include/linux/vfio.h index d4ce14d..ec9f74f 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -100,6 +100,9 @@ extern void vfio_unregister_iommu_driver( extern long vfio_external_check_extension(struct vfio_group *group, unsigned long arg); +struct kvm; +extern void vfio_group_notify(struct vfio_group *group, struct kvm *kvm); + /* * Sub-module helpers */ @@ -149,6 +152,7 @@ extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage); #define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1 +#define VFIO_GROUP_NOTIFY_SET_KVM 2 extern int vfio_register_notifier(struct device *dev, struct notifier_block *nb); -- 1.9.1