From patchwork Tue Sep 17 01:02:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiwei Bie X-Patchwork-Id: 11147967 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2DFA21708 for ; Tue, 17 Sep 2019 01:05:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BF27214D9 for ; Tue, 17 Sep 2019 01:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390686AbfIQBFB (ORCPT ); Mon, 16 Sep 2019 21:05:01 -0400 Received: from mga04.intel.com ([192.55.52.120]:34819 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727996AbfIQBFB (ORCPT ); Mon, 16 Sep 2019 21:05:01 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Sep 2019 18:05:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,514,1559545200"; d="scan'208";a="180611948" Received: from dpdk-virtio-tbie-2.sh.intel.com ([10.67.104.71]) by orsmga008.jf.intel.com with ESMTP; 16 Sep 2019 18:04:58 -0700 From: Tiwei Bie To: mst@redhat.com, jasowang@redhat.com, alex.williamson@redhat.com, maxime.coquelin@redhat.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, dan.daly@intel.com, cunming.liang@intel.com, zhihong.wang@intel.com, lingshan.zhu@intel.com, tiwei.bie@intel.com Subject: [RFC v4 1/3] vfio: support getting vfio device from device fd Date: Tue, 17 Sep 2019 09:02:02 +0800 Message-Id: <20190917010204.30376-2-tiwei.bie@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190917010204.30376-1-tiwei.bie@intel.com> References: <20190917010204.30376-1-tiwei.bie@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch introduces the support for getting VFIO device from VFIO device fd. With this support, it's possible for vhost to get VFIO device from the group fd and device fd set by the userspace. Signed-off-by: Tiwei Bie --- drivers/vfio/vfio.c | 25 +++++++++++++++++++++++++ include/linux/vfio.h | 4 ++++ 2 files changed, 29 insertions(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 388597930b64..697fd079bb3f 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -890,6 +890,31 @@ static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group, return device; } +struct vfio_device *vfio_device_get_from_fd(struct vfio_group *group, + int device_fd) +{ + struct fd f; + struct vfio_device *it, *device = ERR_PTR(-ENODEV); + + f = fdget(device_fd); + if (!f.file) + return ERR_PTR(-EBADF); + + mutex_lock(&group->device_lock); + list_for_each_entry(it, &group->device_list, group_next) { + if (it == f.file->private_data) { + device = it; + vfio_device_get(device); + break; + } + } + mutex_unlock(&group->device_lock); + + fdput(f); + return device; +} +EXPORT_SYMBOL_GPL(vfio_device_get_from_fd); + /* * Caller must hold a reference to the vfio_device */ diff --git a/include/linux/vfio.h b/include/linux/vfio.h index e42a711a2800..e75b24fd7c5c 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -15,6 +15,8 @@ #include #include +struct vfio_group; + /** * struct vfio_device_ops - VFIO bus driver device callbacks * @@ -50,6 +52,8 @@ extern int vfio_add_group_dev(struct device *dev, extern void *vfio_del_group_dev(struct device *dev); extern struct vfio_device *vfio_device_get_from_dev(struct device *dev); +extern struct vfio_device *vfio_device_get_from_fd(struct vfio_group *group, + int device_fd); extern void vfio_device_put(struct vfio_device *device); extern void *vfio_device_data(struct vfio_device *device);