From patchwork Tue Dec 19 18:56:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 1878148 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4SvmGw1pCtz1ydc for ; Wed, 20 Dec 2023 06:00:24 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rFfKF-0006hO-HG; Tue, 19 Dec 2023 14:00:19 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rFfJg-0005HL-F4 for qemu-devel@nongnu.org; Tue, 19 Dec 2023 13:59:46 -0500 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rFfJe-0007U9-Ez for qemu-devel@nongnu.org; Tue, 19 Dec 2023 13:59:44 -0500 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4SvmG33m9Bz4xS5; Wed, 20 Dec 2023 05:59:39 +1100 (AEDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4SvmFz18tZz4xR5; Wed, 20 Dec 2023 05:59:34 +1100 (AEDT) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-devel@nongnu.org Cc: Eric Auger , Zhenzhong Duan , Peter Maydell , Richard Henderson , Nicholas Piggin , Harsh Prateek Bora , Thomas Huth , Eric Farman , Alex Williamson , Matthew Rosato , =?utf-8?q?C=C3=A9dric_Le_Goater?= , Nicolin Chen Subject: [PULL 32/47] vfio/platform: Make vfio cdev pre-openable by passing a file handle Date: Tue, 19 Dec 2023 19:56:28 +0100 Message-ID: <20231219185643.725448-33-clg@redhat.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231219185643.725448-1-clg@redhat.com> References: <20231219185643.725448-1-clg@redhat.com> MIME-Version: 1.0 Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=7/MV=H6=redhat.com=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Zhenzhong Duan This gives management tools like libvirt a chance to open the vfio cdev with privilege and pass FD to qemu. This way qemu never needs to have privilege to open a VFIO or iommu cdev node. Signed-off-by: Zhenzhong Duan Reviewed-by: Cédric Le Goater Tested-by: Nicolin Chen Signed-off-by: Cédric Le Goater --- hw/vfio/platform.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c index 98ae4bc655b401250bd4cb943e4efec97f486a5f..a97d9c6234ccac0ba26b44d3e2290616eda5debd 100644 --- a/hw/vfio/platform.c +++ b/hw/vfio/platform.c @@ -531,14 +531,13 @@ static VFIODeviceOps vfio_platform_ops = { */ static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp) { - struct stat st; int ret; - /* @sysfsdev takes precedence over @host */ - if (vbasedev->sysfsdev) { + /* @fd takes precedence over @sysfsdev which takes precedence over @host */ + if (vbasedev->fd < 0 && vbasedev->sysfsdev) { g_free(vbasedev->name); vbasedev->name = g_path_get_basename(vbasedev->sysfsdev); - } else { + } else if (vbasedev->fd < 0) { if (!vbasedev->name || strchr(vbasedev->name, '/')) { error_setg(errp, "wrong host device name"); return -EINVAL; @@ -548,10 +547,9 @@ static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp) vbasedev->name); } - if (stat(vbasedev->sysfsdev, &st) < 0) { - error_setg_errno(errp, errno, - "failed to get the sysfs host device file status"); - return -errno; + ret = vfio_device_get_name(vbasedev, errp); + if (ret) { + return ret; } ret = vfio_attach_device(vbasedev->name, vbasedev, @@ -658,6 +656,20 @@ static Property vfio_platform_dev_properties[] = { DEFINE_PROP_END_OF_LIST(), }; +static void vfio_platform_instance_init(Object *obj) +{ + VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(obj); + + vdev->vbasedev.fd = -1; +} + +#ifdef CONFIG_IOMMUFD +static void vfio_platform_set_fd(Object *obj, const char *str, Error **errp) +{ + vfio_device_set_fd(&VFIO_PLATFORM_DEVICE(obj)->vbasedev, str, errp); +} +#endif + static void vfio_platform_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); @@ -665,6 +677,9 @@ static void vfio_platform_class_init(ObjectClass *klass, void *data) dc->realize = vfio_platform_realize; device_class_set_props(dc, vfio_platform_dev_properties); +#ifdef CONFIG_IOMMUFD + object_class_property_add_str(klass, "fd", NULL, vfio_platform_set_fd); +#endif dc->vmsd = &vfio_platform_vmstate; dc->desc = "VFIO-based platform device assignment"; sbc->connect_irq_notifier = vfio_start_irqfd_injection; @@ -677,6 +692,7 @@ static const TypeInfo vfio_platform_dev_info = { .name = TYPE_VFIO_PLATFORM, .parent = TYPE_SYS_BUS_DEVICE, .instance_size = sizeof(VFIOPlatformDevice), + .instance_init = vfio_platform_instance_init, .class_init = vfio_platform_class_init, .class_size = sizeof(VFIOPlatformDeviceClass), };