From patchwork Mon Jun 14 15:08:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12319105 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62F5CC49EB9 for ; Mon, 14 Jun 2021 15:09:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4BDB561352 for ; Mon, 14 Jun 2021 15:09:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233450AbhFNPLY (ORCPT ); Mon, 14 Jun 2021 11:11:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233048AbhFNPLX (ORCPT ); Mon, 14 Jun 2021 11:11:23 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D69C5C061574; Mon, 14 Jun 2021 08:09:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=mK8kZxMmwpLFLvKSSecAo5yq1vW8IxoaNB0nNbcvV1U=; b=yr0m7Jr4p1aUsn7BUssbX4oHY2 qUU9y0N6s76eAqimmHkw5NlIkP/7mWfuIywU9DEBhC2kXVnFjkrzZdF6cQOyXIAt32zm6fYrVYUMm Pgdo0fmC119vqo+nxX3IWSrUpJepNJ1zY07vfQvrPNczgWz3hkMAo/f6+FVz0HpfbKxGapMy2CwQS h+78w4IP468qSWZq9oK965uP+Jqm+vI4K8aVu+T5ETZu8EQSi3zJepJfyMGVKfoDHBZE0yAnHah+J XZWKpwRIjoAYBbzB0ObFg25j/iJYjiYJpWeCScekbq9T3pm96cCfCqXl2f+v+Wic/qjVq0nXIiQi8 TmYiwrLQ==; Received: from [2001:4bb8:19b:fdce:4b1a:b4aa:22d8:1629] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1lsoDA-00Efmq-FH; Mon, 14 Jun 2021 15:09:13 +0000 From: Christoph Hellwig To: Greg Kroah-Hartman , Jason Gunthorpe , Alex Williamson , Kirti Wankhede Cc: David Airlie , Tony Krowiak , Christian Borntraeger , Cornelia Huck , Jonathan Corbet , Daniel Vetter , dri-devel@lists.freedesktop.org, Vasily Gorbik , Heiko Carstens , intel-gfx@lists.freedesktop.org, Jani Nikula , Jason Herne , Joonas Lahtinen , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-s390@vger.kernel.org, Halil Pasic , "Rafael J. Wysocki" , Rodrigo Vivi Subject: [PATCH 07/10] vfio/mdev: Allow the mdev_parent_ops to specify the device driver to bind Date: Mon, 14 Jun 2021 17:08:43 +0200 Message-Id: <20210614150846.4111871-8-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210614150846.4111871-1-hch@lst.de> References: <20210614150846.4111871-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Jason Gunthorpe This allows a mdev driver to opt out of using vfio_mdev.c, instead the driver will provide a 'struct mdev_driver' and register directly with the driver core. Much of mdev_parent_ops becomes unused in this mode: - create()/remove() are done via the mdev_driver probe()/remove() - mdev_attr_groups becomes mdev_driver driver.dev_groups - Wrapper function callbacks are replaced with the same ones from struct vfio_device_ops Signed-off-by: Jason Gunthorpe Signed-off-by: Christoph Hellwig Reviewed-by: Cornelia Huck --- drivers/vfio/mdev/mdev_core.c | 30 ++++++++++++++++++++++-------- drivers/vfio/mdev/mdev_driver.c | 10 ++++++++++ include/linux/mdev.h | 2 ++ 3 files changed, 34 insertions(+), 8 deletions(-) diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index ff8c1a845166..e4581ec093a6 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -94,9 +94,11 @@ static void mdev_device_remove_common(struct mdev_device *mdev) mdev_remove_sysfs_files(mdev); device_del(&mdev->dev); lockdep_assert_held(&parent->unreg_sem); - ret = parent->ops->remove(mdev); - if (ret) - dev_err(&mdev->dev, "Remove failed: err=%d\n", ret); + if (parent->ops->remove) { + ret = parent->ops->remove(mdev); + if (ret) + dev_err(&mdev->dev, "Remove failed: err=%d\n", ret); + } /* Balances with device_initialize() */ put_device(&mdev->dev); @@ -127,7 +129,9 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops) char *envp[] = { env_string, NULL }; /* check for mandatory ops */ - if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups) + if (!ops || !ops->supported_type_groups) + return -EINVAL; + if (!ops->device_driver && (!ops->create || !ops->remove)) return -EINVAL; dev = get_device(dev); @@ -256,6 +260,7 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) int ret; struct mdev_device *mdev, *tmp; struct mdev_parent *parent = type->parent; + struct mdev_driver *drv = parent->ops->device_driver; mutex_lock(&mdev_list_lock); @@ -296,14 +301,22 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) goto out_put_device; } - ret = parent->ops->create(mdev); - if (ret) - goto out_unlock; + if (parent->ops->create) { + ret = parent->ops->create(mdev); + if (ret) + goto out_unlock; + } ret = device_add(&mdev->dev); if (ret) goto out_remove; + if (!drv) + drv = &vfio_mdev_driver; + ret = device_driver_attach(&drv->driver, &mdev->dev); + if (ret) + goto out_del; + ret = mdev_create_sysfs_files(mdev); if (ret) goto out_del; @@ -317,7 +330,8 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) out_del: device_del(&mdev->dev); out_remove: - parent->ops->remove(mdev); + if (parent->ops->remove) + parent->ops->remove(mdev); out_unlock: up_read(&parent->unreg_sem); out_put_device: diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c index 041699571b7e..c368ec824e2b 100644 --- a/drivers/vfio/mdev/mdev_driver.c +++ b/drivers/vfio/mdev/mdev_driver.c @@ -71,10 +71,20 @@ static int mdev_remove(struct device *dev) return 0; } +static int mdev_match(struct device *dev, struct device_driver *drv) +{ + /* + * No drivers automatically match. Drivers are only bound by explicit + * device_driver_attach() + */ + return 0; +} + struct bus_type mdev_bus_type = { .name = "mdev", .probe = mdev_probe, .remove = mdev_remove, + .match = mdev_match, }; EXPORT_SYMBOL_GPL(mdev_bus_type); diff --git a/include/linux/mdev.h b/include/linux/mdev.h index 1fb34ea394ad..3a38598c2605 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -55,6 +55,7 @@ struct device *mtype_get_parent_dev(struct mdev_type *mtype); * register the device to mdev module. * * @owner: The module owner. + * @device_driver: Which device driver to probe() on newly created devices * @dev_attr_groups: Attributes of the parent device. * @mdev_attr_groups: Attributes of the mediated device. * @supported_type_groups: Attributes to define supported types. It is mandatory @@ -103,6 +104,7 @@ struct device *mtype_get_parent_dev(struct mdev_type *mtype); **/ struct mdev_parent_ops { struct module *owner; + struct mdev_driver *device_driver; const struct attribute_group **dev_attr_groups; const struct attribute_group **mdev_attr_groups; struct attribute_group **supported_type_groups;