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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 E6FC4C10F14 for ; Tue, 15 Oct 2019 12:17:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C13B021848 for ; Tue, 15 Oct 2019 12:17:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727876AbfJOMRe (ORCPT ); Tue, 15 Oct 2019 08:17:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57608 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726004AbfJOMRe (ORCPT ); Tue, 15 Oct 2019 08:17:34 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 12DEBC05B00E; Tue, 15 Oct 2019 12:17:33 +0000 (UTC) Received: from [10.72.12.168] (ovpn-12-168.pek2.redhat.com [10.72.12.168]) by smtp.corp.redhat.com (Postfix) with ESMTP id 99C9760BE2; Tue, 15 Oct 2019 12:17:02 +0000 (UTC) Subject: Re: [PATCH V3 4/7] mdev: introduce device specific ops To: Cornelia Huck 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, tiwei.bie@intel.com, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, xiao.w.wang@intel.com, haotian.wang@sifive.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, freude@linux.ibm.com, lingshan.zhu@intel.com, idos@mellanox.com, eperezma@redhat.com, lulu@redhat.com, parav@mellanox.com, christophe.de.dinechin@gmail.com, kevin.tian@intel.com References: <20191011081557.28302-1-jasowang@redhat.com> <20191011081557.28302-5-jasowang@redhat.com> <20191015124137.4f948bd2.cohuck@redhat.com> From: Jason Wang Message-ID: Date: Tue, 15 Oct 2019 20:17:01 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191015124137.4f948bd2.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 15 Oct 2019 12:17:33 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/10/15 下午6:41, Cornelia Huck wrote: > On Fri, 11 Oct 2019 16:15:54 +0800 > Jason Wang wrote: > >> Currently, except for the create and remove, the rest of >> mdev_parent_ops is designed for vfio-mdev driver only and may not help >> for kernel mdev driver. With the help of class id, this patch >> introduces device specific callbacks inside mdev_device >> structure. This allows different set of callback to be used by >> vfio-mdev and virtio-mdev. >> >> Signed-off-by: Jason Wang >> --- >> .../driver-api/vfio-mediated-device.rst | 22 +++++--- >> MAINTAINERS | 1 + >> drivers/gpu/drm/i915/gvt/kvmgt.c | 18 ++++--- >> drivers/s390/cio/vfio_ccw_ops.c | 18 ++++--- >> drivers/s390/crypto/vfio_ap_ops.c | 14 +++-- >> drivers/vfio/mdev/mdev_core.c | 9 +++- >> drivers/vfio/mdev/mdev_private.h | 1 + >> drivers/vfio/mdev/vfio_mdev.c | 37 ++++++------- >> include/linux/mdev.h | 42 +++------------ >> include/linux/vfio_mdev.h | 52 +++++++++++++++++++ >> samples/vfio-mdev/mbochs.c | 20 ++++--- >> samples/vfio-mdev/mdpy.c | 21 +++++--- >> samples/vfio-mdev/mtty.c | 18 ++++--- >> 13 files changed, 177 insertions(+), 96 deletions(-) >> create mode 100644 include/linux/vfio_mdev.h >> >> diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst >> index 2035e48da7b2..553574ebba73 100644 >> --- a/Documentation/driver-api/vfio-mediated-device.rst >> +++ b/Documentation/driver-api/vfio-mediated-device.rst >> @@ -152,11 +152,20 @@ callbacks per mdev parent device, per mdev type, or any other categorization. >> Vendor drivers are expected to be fully asynchronous in this respect or >> provide their own internal resource protection.) >> >> -The callbacks in the mdev_parent_ops structure are as follows: >> +In order to support multiple types of device/driver, device needs to >> +provide both class_id and device_ops through: > "As multiple types of mediated devices may be supported, the device > needs to set up the class id and the device specific callbacks via:" > > ? > >> >> -* open: open callback of mediated device >> -* close: close callback of mediated device >> -* ioctl: ioctl callback of mediated device >> + void mdev_set_class(struct mdev_device *mdev, u16 id, const void *ops); >> + >> +The class_id is used to be paired with ids in id_table in mdev_driver >> +structure for probing the correct driver. > "The class id (specified in id) is used to match a device with an mdev > driver via its id table." > > ? > >> The device_ops is device >> +specific callbacks which can be get through mdev_get_dev_ops() >> +function by mdev bus driver. > "The device specific callbacks (specified in *ops) are obtainable via > mdev_get_dev_ops() (for use by the mdev bus driver.)" > > ? > >> For vfio-mdev device, its device specific >> +ops are as follows: > "A vfio-mdev device (class id MDEV_ID_VFIO) uses the following > device-specific ops:" > > ? All you propose is better than what I wrote, will change the docs. > >> + >> +* open: open callback of vfio mediated device >> +* close: close callback of vfio mediated device >> +* ioctl: ioctl callback of vfio mediated device >> * read : read emulation callback >> * write: write emulation callback >> * mmap: mmap emulation callback >> @@ -167,9 +176,10 @@ register itself with the mdev core driver:: >> extern int mdev_register_device(struct device *dev, >> const struct mdev_parent_ops *ops); >> >> -It is also required to specify the class_id through:: >> +It is also required to specify the class_id and device specific ops through:: >> >> - extern int mdev_set_class(struct device *dev, u16 id); >> + extern int mdev_set_class(struct device *dev, u16 id, >> + const void *ops); > Apologies if that has already been discussed, but do we want a 1:1 > relationship between id and ops, or can different devices with the same > id register different ops? I think we have a N:1 mapping between id and ops, e.g we want both virtio-mdev and vhost-mdev use a single set of device ops. Thanks > If the former, would it make sense to first > register the ops for an id (once), and then have the ->create callback > only set the class id (with the core doing the lookup of the ops)? > >> >> However, the mdev_parent_ops structure is not required in the function call >> that a driver should use to unregister itself with the mdev core driver:: From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: [PATCH V3 4/7] mdev: introduce device specific ops Date: Tue, 15 Oct 2019 20:17:01 +0800 Message-ID: References: <20191011081557.28302-1-jasowang@redhat.com> <20191011081557.28302-5-jasowang@redhat.com> <20191015124137.4f948bd2.cohuck@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20191015124137.4f948bd2.cohuck@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Cornelia Huck 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, tiwei.bie@intel.com, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, xiao.w.wang@intel.com, haotian.wang@sifive.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.c List-Id: dri-devel@lists.freedesktop.org On 2019/10/15 下午6:41, Cornelia Huck wrote: > On Fri, 11 Oct 2019 16:15:54 +0800 > Jason Wang wrote: > >> Currently, except for the create and remove, the rest of >> mdev_parent_ops is designed for vfio-mdev driver only and may not help >> for kernel mdev driver. With the help of class id, this patch >> introduces device specific callbacks inside mdev_device >> structure. This allows different set of callback to be used by >> vfio-mdev and virtio-mdev. >> >> Signed-off-by: Jason Wang >> --- >> .../driver-api/vfio-mediated-device.rst | 22 +++++--- >> MAINTAINERS | 1 + >> drivers/gpu/drm/i915/gvt/kvmgt.c | 18 ++++--- >> drivers/s390/cio/vfio_ccw_ops.c | 18 ++++--- >> drivers/s390/crypto/vfio_ap_ops.c | 14 +++-- >> drivers/vfio/mdev/mdev_core.c | 9 +++- >> drivers/vfio/mdev/mdev_private.h | 1 + >> drivers/vfio/mdev/vfio_mdev.c | 37 ++++++------- >> include/linux/mdev.h | 42 +++------------ >> include/linux/vfio_mdev.h | 52 +++++++++++++++++++ >> samples/vfio-mdev/mbochs.c | 20 ++++--- >> samples/vfio-mdev/mdpy.c | 21 +++++--- >> samples/vfio-mdev/mtty.c | 18 ++++--- >> 13 files changed, 177 insertions(+), 96 deletions(-) >> create mode 100644 include/linux/vfio_mdev.h >> >> diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst >> index 2035e48da7b2..553574ebba73 100644 >> --- a/Documentation/driver-api/vfio-mediated-device.rst >> +++ b/Documentation/driver-api/vfio-mediated-device.rst >> @@ -152,11 +152,20 @@ callbacks per mdev parent device, per mdev type, or any other categorization. >> Vendor drivers are expected to be fully asynchronous in this respect or >> provide their own internal resource protection.) >> >> -The callbacks in the mdev_parent_ops structure are as follows: >> +In order to support multiple types of device/driver, device needs to >> +provide both class_id and device_ops through: > "As multiple types of mediated devices may be supported, the device > needs to set up the class id and the device specific callbacks via:" > > ? > >> >> -* open: open callback of mediated device >> -* close: close callback of mediated device >> -* ioctl: ioctl callback of mediated device >> + void mdev_set_class(struct mdev_device *mdev, u16 id, const void *ops); >> + >> +The class_id is used to be paired with ids in id_table in mdev_driver >> +structure for probing the correct driver. > "The class id (specified in id) is used to match a device with an mdev > driver via its id table." > > ? > >> The device_ops is device >> +specific callbacks which can be get through mdev_get_dev_ops() >> +function by mdev bus driver. > "The device specific callbacks (specified in *ops) are obtainable via > mdev_get_dev_ops() (for use by the mdev bus driver.)" > > ? > >> For vfio-mdev device, its device specific >> +ops are as follows: > "A vfio-mdev device (class id MDEV_ID_VFIO) uses the following > device-specific ops:" > > ? All you propose is better than what I wrote, will change the docs. > >> + >> +* open: open callback of vfio mediated device >> +* close: close callback of vfio mediated device >> +* ioctl: ioctl callback of vfio mediated device >> * read : read emulation callback >> * write: write emulation callback >> * mmap: mmap emulation callback >> @@ -167,9 +176,10 @@ register itself with the mdev core driver:: >> extern int mdev_register_device(struct device *dev, >> const struct mdev_parent_ops *ops); >> >> -It is also required to specify the class_id through:: >> +It is also required to specify the class_id and device specific ops through:: >> >> - extern int mdev_set_class(struct device *dev, u16 id); >> + extern int mdev_set_class(struct device *dev, u16 id, >> + const void *ops); > Apologies if that has already been discussed, but do we want a 1:1 > relationship between id and ops, or can different devices with the same > id register different ops? I think we have a N:1 mapping between id and ops, e.g we want both virtio-mdev and vhost-mdev use a single set of device ops. Thanks > If the former, would it make sense to first > register the ops for an id (once), and then have the ->create callback > only set the class id (with the core doing the lookup of the ops)? > >> >> However, the mdev_parent_ops structure is not required in the function call >> that a driver should use to unregister itself with the mdev core driver::