From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 BB2D1C4CEC9 for ; Tue, 17 Sep 2019 12:42:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 900B521881 for ; Tue, 17 Sep 2019 12:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728578AbfIQMm5 (ORCPT ); Tue, 17 Sep 2019 08:42:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52494 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728117AbfIQMm5 (ORCPT ); Tue, 17 Sep 2019 08:42:57 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6C6F54E83C; Tue, 17 Sep 2019 12:42:56 +0000 (UTC) Received: from gondolin (dhcp-192-230.str.redhat.com [10.33.192.230]) by smtp.corp.redhat.com (Postfix) with ESMTP id CEC546012E; Tue, 17 Sep 2019 12:42:42 +0000 (UTC) Date: Tue, 17 Sep 2019 14:42:40 +0200 From: Cornelia Huck To: Jason Wang Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, kwankhede@nvidia.com, alex.williamson@redhat.com, mst@redhat.com, zhenyuw@linux.intel.com, zhi.a.wang@intel.com, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, airlied@linux.ie, daniel@ffwll.ch, farman@linux.ibm.com, pasic@linux.ibm.com, sebott@linux.ibm.com, oberpar@linux.ibm.com, heiko.carstens@de.ibm.com, gor@linux.ibm.com, borntraeger@de.ibm.com, akrowiak@linux.ibm.com, pmorel@linux.ibm.com, freude@linux.ibm.com, tiwei.bie@intel.com, virtualization@lists.linux-foundation.org, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, idos@mellanox.com, xiao.w.wang@intel.com, lingshan.zhu@intel.com Subject: Re: [RFC PATCH 2/2] mdev: introduce device specific ops Message-ID: <20190917144240.6a59b65f.cohuck@redhat.com> In-Reply-To: <20190912094012.29653-3-jasowang@redhat.com> References: <20190912094012.29653-1-jasowang@redhat.com> <20190912094012.29653-3-jasowang@redhat.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 17 Sep 2019 12:42:56 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 12 Sep 2019 17:40:12 +0800 Jason Wang wrote: > Currently, except for the crate and remove. The rest fields of > mdev_parent_ops is just designed for vfio-mdev driver and may not help > for kernel mdev driver. So follow the device id support by previous > patch, this patch introduces device specific ops which points to > device specific ops (e.g vfio ops). This allows the future drivers > like virtio-mdev to implement its own device specific ops. > > Signed-off-by: Jason Wang > --- > drivers/gpu/drm/i915/gvt/kvmgt.c | 14 +++--- > drivers/s390/cio/vfio_ccw_ops.c | 14 +++--- > drivers/s390/crypto/vfio_ap_ops.c | 10 +++-- > drivers/vfio/mdev/vfio_mdev.c | 30 +++++++------ > include/linux/mdev.h | 72 ++++++++++++++++++------------- > samples/vfio-mdev/mbochs.c | 16 ++++--- > samples/vfio-mdev/mdpy.c | 16 ++++--- > samples/vfio-mdev/mtty.c | 14 +++--- > 8 files changed, 113 insertions(+), 73 deletions(-) > diff --git a/include/linux/mdev.h b/include/linux/mdev.h > index f85045392120..3b8a76bc69cf 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -27,27 +27,9 @@ int mdev_set_iommu_device(struct device *dev, struct device *iommu_device); > struct device *mdev_get_iommu_device(struct device *dev); > > /** > - * struct mdev_parent_ops - Structure to be registered for each parent device to > - * register the device to mdev module. > + * struct vfio_mdev_parent_ops - Structure to be registered for each > + * parent device to register the device to vfio-mdev module. > * > - * @owner: The module owner. > - * @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 > - * to provide supported types. > - * @create: Called to allocate basic resources in parent device's > - * driver for a particular mediated device. It is > - * mandatory to provide create ops. > - * @kobj: kobject of type for which 'create' is called. > - * @mdev: mdev_device structure on of mediated device > - * that is being created > - * Returns integer: success (0) or error (< 0) > - * @remove: Called to free resources in parent device's driver for a > - * a mediated device. It is mandatory to provide 'remove' > - * ops. > - * @mdev: mdev_device device structure which is being > - * destroyed > - * Returns integer: success (0) or error (< 0) > * @open: Open mediated device. > * @mdev: mediated device. > * Returns integer: success (0) or error (< 0) > @@ -72,6 +54,43 @@ struct device *mdev_get_iommu_device(struct device *dev); > * @mmap: mmap callback > * @mdev: mediated device structure > * @vma: vma structure > + */ > +struct vfio_mdev_parent_ops { > + int (*open)(struct mdev_device *mdev); > + void (*release)(struct mdev_device *mdev); > + ssize_t (*read)(struct mdev_device *mdev, char __user *buf, > + size_t count, loff_t *ppos); > + ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, > + size_t count, loff_t *ppos); > + long (*ioctl)(struct mdev_device *mdev, unsigned int cmd, > + unsigned long arg); > + int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma); > +}; > + > +/** > + * struct mdev_parent_ops - Structure to be registered for each parent device to > + * register the device to mdev module. > + * > + * @owner: The module owner. > + * @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 > + * to provide supported types. > + * @create: Called to allocate basic resources in parent device's > + * driver for a particular mediated device. It is > + * mandatory to provide create ops. > + * @kobj: kobject of type for which 'create' is called. > + * @mdev: mdev_device structure on of mediated device > + * that is being created > + * Returns integer: success (0) or error (< 0) > + * @remove: Called to free resources in parent device's driver for a > + * a mediated device. It is mandatory to provide 'remove' > + * ops. > + * @mdev: mdev_device device structure which is being > + * destroyed > + * Returns integer: success (0) or error (< 0) > + * @device_ops: Device specific emulation callback. > + * > * Parent device that support mediated device should be registered with mdev > * module with mdev_parent_ops structure. > **/ > @@ -83,15 +102,7 @@ struct mdev_parent_ops { > > int (*create)(struct kobject *kobj, struct mdev_device *mdev); > int (*remove)(struct mdev_device *mdev); > - int (*open)(struct mdev_device *mdev); > - void (*release)(struct mdev_device *mdev); > - ssize_t (*read)(struct mdev_device *mdev, char __user *buf, > - size_t count, loff_t *ppos); > - ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, > - size_t count, loff_t *ppos); > - long (*ioctl)(struct mdev_device *mdev, unsigned int cmd, > - unsigned long arg); > - int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma); > + const void *device_ops; > }; > > /* interface for exporting mdev supported type attributes */ This basically looks like a split between stuff that is always triggered from userspace (create and the like) and stuff that is triggered from userspace for vfio mdevs, but not necessarily for other mdevs. Seems reasonable at a glance. If we decide to go forward with this, we should also update the documentation (split out stuff from driver-api/vfio-mediated-device.rst etc.)