From patchwork Thu Sep 1 14:37:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Tian, Kevin" X-Patchwork-Id: 12961963 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 02598ECAAD3 for ; Thu, 1 Sep 2022 07:23:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233906AbiIAHXJ (ORCPT ); Thu, 1 Sep 2022 03:23:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60740 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233905AbiIAHWq (ORCPT ); Thu, 1 Sep 2022 03:22:46 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D019FB4B; Thu, 1 Sep 2022 00:21:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662016874; x=1693552874; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=yPWKM7p4vcbptQIIIvkMNuxbJPUQXyRKvKLc8vZijDk=; b=Uh8be+pyyBHL2e3eeQK6snPNM/5QulzjbLvPoAu5ZAMXv7PnzCH0XEN1 m8LmdQ6XmPrApSgmuFcOxGBXM+ZNGvzOJb953hRZ2RVz5YIu96nnJLNv4 e4q8gS6b+j2xSp5ZIKE9UH6ihpJb/G1CO5HshVKEAM8viSMFh4YEKBjJh Mxw1/bjTu4NuXa/2s563QHM/HDWqsWzHf0mMKXphdrH+vSjajHVzbe0Al iXbaMwt/5Rtj398qwjyZe/u/1RjxnVHwgnj9vPVdWhWTVinD7QiD1NjTR JX9dbyfovlYVfybCJfuSIoDOtbu9Rg2Wr4rKCLhalTyL2sji0At7nVggi Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10456"; a="381934375" X-IronPort-AV: E=Sophos;i="5.93,280,1654585200"; d="scan'208";a="381934375" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2022 00:19:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,280,1654585200"; d="scan'208";a="673720896" Received: from sqa-gate.sh.intel.com (HELO michael.clx.dev.tsp.org) ([10.239.48.212]) by fmsmga008.fm.intel.com with ESMTP; 01 Sep 2022 00:19:41 -0700 From: Kevin Tian To: Zhenyu Wang , Zhi Wang , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Eric Farman , Matthew Rosato , Halil Pasic , Vineeth Vijayan , Peter Oberparleiter , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Tony Krowiak , Jason Herne , Harald Freudenberger , Diana Craciun , Alex Williamson , Cornelia Huck , Longfang Liu , Shameer Kolothum , Jason Gunthorpe , Yishai Hadas , Kevin Tian , Eric Auger , Kirti Wankhede , Leon Romanovsky , Abhishek Sahu , intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org Cc: Yi Liu Subject: [PATCH v2 15/15] vfio: Add struct device to vfio_device Date: Thu, 1 Sep 2022 22:37:47 +0800 Message-Id: <20220901143747.32858-16-kevin.tian@intel.com> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20220901143747.32858-1-kevin.tian@intel.com> References: <20220901143747.32858-1-kevin.tian@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Yi Liu and replace kref. With it a 'vfio-dev/vfioX' node is created under the sysfs path of the parent, indicating the device is bound to a vfio driver, e.g.: /sys/devices/pci0000\:6f/0000\:6f\:01.0/vfio-dev/vfio0 It is also a preparatory step toward adding cdev for supporting future device-oriented uAPI. Add Documentation/ABI/testing/sysfs-devices-vfio-dev. Also take this chance to rename chardev 'vfio' to 'vfio-group' in /proc/devices. Suggested-by: Jason Gunthorpe Signed-off-by: Yi Liu Signed-off-by: Kevin Tian Reviewed-by: Jason Gunthorpe --- .../ABI/testing/sysfs-devices-vfio-dev | 8 +++ drivers/vfio/vfio_main.c | 67 +++++++++++++++---- include/linux/vfio.h | 6 +- 3 files changed, 66 insertions(+), 15 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-devices-vfio-dev diff --git a/Documentation/ABI/testing/sysfs-devices-vfio-dev b/Documentation/ABI/testing/sysfs-devices-vfio-dev new file mode 100644 index 000000000000..e21424fd9666 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-vfio-dev @@ -0,0 +1,8 @@ +What: /sys/...//vfio-dev/vfioX/ +Date: September 2022 +Contact: Yi Liu +Description: + This directory is created when the device is bound to a + vfio driver. The layout under this directory matches what + exists for a standard 'struct device'. 'X' is a unique + index marking this device in vfio. diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index bfa675d314ab..141f55c3faf5 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -46,6 +46,8 @@ static struct vfio { struct mutex group_lock; /* locks group_list */ struct ida group_ida; dev_t group_devt; + struct class *device_class; + struct ida device_ida; } vfio; struct vfio_iommu_driver { @@ -483,12 +485,13 @@ static struct vfio_device *vfio_group_get_device(struct vfio_group *group, * VFIO driver API */ /* Release helper called by vfio_put_device() */ -void vfio_device_release(struct kref *kref) +static void vfio_device_release(struct device *dev) { struct vfio_device *device = - container_of(kref, struct vfio_device, kref); + container_of(dev, struct vfio_device, device); vfio_release_device_set(device); + ida_free(&vfio.device_ida, device->index); /* * kvfree() cannot be done here due to a life cycle mess in @@ -498,7 +501,6 @@ void vfio_device_release(struct kref *kref) */ device->ops->release(device); } -EXPORT_SYMBOL_GPL(vfio_device_release); /* * Alloc and initialize vfio_device so it can be registered to vfio @@ -546,6 +548,13 @@ int vfio_init_device(struct vfio_device *device, struct device *dev, { int ret; + ret = ida_alloc_max(&vfio.device_ida, MINORMASK, GFP_KERNEL); + if (ret < 0) { + dev_dbg(dev, "Error to alloc index\n"); + return ret; + } + + device->index = ret; init_completion(&device->comp); device->dev = dev; device->ops = ops; @@ -556,11 +565,15 @@ int vfio_init_device(struct vfio_device *device, struct device *dev, goto out_uninit; } - kref_init(&device->kref); + device_initialize(&device->device); + device->device.release = vfio_device_release; + device->device.class = vfio.device_class; + device->device.parent = device->dev; return 0; out_uninit: vfio_release_device_set(device); + ida_free(&vfio.device_ida, device->index); return ret; } EXPORT_SYMBOL_GPL(vfio_init_device); @@ -657,6 +670,7 @@ static int __vfio_register_dev(struct vfio_device *device, struct vfio_group *group) { struct vfio_device *existing_device; + int ret; if (IS_ERR(group)) return PTR_ERR(group); @@ -673,16 +687,21 @@ static int __vfio_register_dev(struct vfio_device *device, dev_WARN(device->dev, "Device already exists on group %d\n", iommu_group_id(group->iommu_group)); vfio_device_put_registration(existing_device); - if (group->type == VFIO_NO_IOMMU || - group->type == VFIO_EMULATED_IOMMU) - iommu_group_remove_device(device->dev); - vfio_group_put(group); - return -EBUSY; + ret = -EBUSY; + goto err_out; } /* Our reference on group is moved to the device */ device->group = group; + ret = dev_set_name(&device->device, "vfio%d", device->index); + if (ret) + goto err_out; + + ret = device_add(&device->device); + if (ret) + goto err_out; + /* Refcounting can't start until the driver calls register */ refcount_set(&device->refcount, 1); @@ -692,6 +711,12 @@ static int __vfio_register_dev(struct vfio_device *device, mutex_unlock(&group->device_lock); return 0; +err_out: + if (group->type == VFIO_NO_IOMMU || + group->type == VFIO_EMULATED_IOMMU) + iommu_group_remove_device(device->dev); + vfio_group_put(group); + return ret; } int vfio_register_group_dev(struct vfio_device *device) @@ -779,6 +804,9 @@ void vfio_unregister_group_dev(struct vfio_device *device) group->dev_counter--; mutex_unlock(&group->device_lock); + /* Balances device_add in register path */ + device_del(&device->device); + if (group->type == VFIO_NO_IOMMU || group->type == VFIO_EMULATED_IOMMU) iommu_group_remove_device(device->dev); @@ -2145,6 +2173,7 @@ static int __init vfio_init(void) int ret; ida_init(&vfio.group_ida); + ida_init(&vfio.device_ida); mutex_init(&vfio.group_lock); mutex_init(&vfio.iommu_drivers_lock); INIT_LIST_HEAD(&vfio.group_list); @@ -2160,12 +2189,20 @@ static int __init vfio_init(void) vfio.class = class_create(THIS_MODULE, "vfio"); if (IS_ERR(vfio.class)) { ret = PTR_ERR(vfio.class); - goto err_class; + goto err_group_class; } vfio.class->devnode = vfio_devnode; - ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, "vfio"); + /* /sys/class/vfio-dev/vfioX */ + vfio.device_class = class_create(THIS_MODULE, "vfio-dev"); + if (IS_ERR(vfio.device_class)) { + ret = PTR_ERR(vfio.device_class); + goto err_dev_class; + } + + ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, + "vfio-group"); if (ret) goto err_alloc_chrdev; @@ -2181,9 +2218,12 @@ static int __init vfio_init(void) err_driver_register: unregister_chrdev_region(vfio.group_devt, MINORMASK + 1); err_alloc_chrdev: + class_destroy(vfio.device_class); + vfio.device_class = NULL; +err_dev_class: class_destroy(vfio.class); vfio.class = NULL; -err_class: +err_group_class: misc_deregister(&vfio_dev); return ret; } @@ -2195,8 +2235,11 @@ static void __exit vfio_cleanup(void) #ifdef CONFIG_VFIO_NOIOMMU vfio_unregister_iommu_driver(&vfio_noiommu_ops); #endif + ida_destroy(&vfio.device_ida); ida_destroy(&vfio.group_ida); unregister_chrdev_region(vfio.group_devt, MINORMASK + 1); + class_destroy(vfio.device_class); + vfio.device_class = NULL; class_destroy(vfio.class); vfio.class = NULL; misc_deregister(&vfio_dev); diff --git a/include/linux/vfio.h b/include/linux/vfio.h index f03447c8774d..5c13f74da1bb 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -45,7 +45,8 @@ struct vfio_device { struct kvm *kvm; /* Members below here are private, not for driver use */ - struct kref kref; /* object life cycle */ + unsigned int index; + struct device device; /* device.kref covers object life circle */ refcount_t refcount; /* user count on registered device*/ unsigned int open_count; struct completion comp; @@ -154,10 +155,9 @@ struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev, int vfio_init_device(struct vfio_device *device, struct device *dev, const struct vfio_device_ops *ops); void vfio_free_device(struct vfio_device *device); -void vfio_device_release(struct kref *kref); static inline void vfio_put_device(struct vfio_device *device) { - kref_put(&device->kref, vfio_device_release); + put_device(&device->device); } int vfio_register_group_dev(struct vfio_device *device);