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Wed, 16 Oct 2019 04:57:31 +0000 From: Parav Pandit To: Jason Wang , "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" CC: "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "cohuck@redhat.com" , "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" , Ido Shamay , "eperezma@redhat.com" , "lulu@redhat.com" , "christophe.de.dinechin@gmail.com" , "kevin.tian@intel.com" Subject: RE: [PATCH V3 1/7] mdev: class id support Thread-Topic: [PATCH V3 1/7] mdev: class id support Thread-Index: AQHVgAxcSI5DY7xDNkGCgUewSafrf6dcuKbA Date: Wed, 16 Oct 2019 04:57:31 +0000 Message-ID: References: <20191011081557.28302-1-jasowang@redhat.com> <20191011081557.28302-2-jasowang@redhat.com> In-Reply-To: <20191011081557.28302-2-jasowang@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: spf=none (sender IP is ) smtp.mailfrom=parav@mellanox.com; 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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 > Cc: virtualization@lists.linux-foundation.org; netdev@vger.kernel.org; > cohuck@redhat.com; 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; Ido Shamay ; > eperezma@redhat.com; lulu@redhat.com; Parav Pandit > ; christophe.de.dinechin@gmail.com; > kevin.tian@intel.com; Jason Wang > Subject: [PATCH V3 1/7] mdev: class id support >=20 > Mdev bus only supports vfio driver right now, so it doesn't implement mat= ch > method. But in the future, we may add drivers other than vfio, the first > driver could be virtio-mdev. This means we need to add device class id > support in bus match method to pair the mdev device and mdev driver > correctly. >=20 > So this patch adds id_table to mdev_driver and class_id for mdev device > with the match method for mdev bus. >=20 > Signed-off-by: Jason Wang > --- > Documentation/driver-api/vfio-mediated-device.rst | 7 ++++++- > drivers/gpu/drm/i915/gvt/kvmgt.c | 1 + > drivers/s390/cio/vfio_ccw_ops.c | 1 + > drivers/s390/crypto/vfio_ap_ops.c | 1 + > drivers/vfio/mdev/mdev_core.c | 11 +++++++++++ > drivers/vfio/mdev/mdev_driver.c | 14 ++++++++++++++ > drivers/vfio/mdev/mdev_private.h | 1 + > drivers/vfio/mdev/vfio_mdev.c | 6 ++++++ > include/linux/mdev.h | 8 ++++++++ > include/linux/mod_devicetable.h | 8 ++++++++ > samples/vfio-mdev/mbochs.c | 1 + > samples/vfio-mdev/mdpy.c | 1 + > samples/vfio-mdev/mtty.c | 1 + > 13 files changed, 60 insertions(+), 1 deletion(-) >=20 > diff --git a/Documentation/driver-api/vfio-mediated-device.rst > b/Documentation/driver-api/vfio-mediated-device.rst > index 25eb7d5b834b..2035e48da7b2 100644 > --- a/Documentation/driver-api/vfio-mediated-device.rst > +++ b/Documentation/driver-api/vfio-mediated-device.rst > @@ -102,12 +102,14 @@ structure to represent a mediated device's driver:: > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > */ > struct mdev_driver { > const char *name; > int (*probe) (struct device *dev); > void (*remove) (struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > A mediated bus driver for mdev should use this structure in the function > calls @@ -165,12 +167,15 @@ register itself with the mdev core driver:: > extern int mdev_register_device(struct device *dev, > const struct mdev_parent_ops *ops); >=20 > +It is also required to specify the class_id through:: > + > + extern int mdev_set_class(struct device *dev, u16 id); Drop extern. In actual API you have correct signature, i.e. struct mdev_device. s/struct device/struct mdev_device. > + > However, the mdev_parent_ops structure is not required in the function c= all > that a driver should use to unregister itself with the mdev core driver:: >=20 > extern void mdev_unregister_device(struct device *dev); >=20 > - > Mediated Device Management Interface Through sysfs > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D >=20 > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c > b/drivers/gpu/drm/i915/gvt/kvmgt.c > index 343d79c1cb7e..17e9d4634c84 100644 > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c > @@ -678,6 +678,7 @@ static int intel_vgpu_create(struct kobject *kobj, > struct mdev_device *mdev) > dev_name(mdev_dev(mdev))); > ret =3D 0; >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > out: > return ret; > } > diff --git a/drivers/s390/cio/vfio_ccw_ops.c > b/drivers/s390/cio/vfio_ccw_ops.c index f0d71ab77c50..b5d223882c6c > 100644 > --- a/drivers/s390/cio/vfio_ccw_ops.c > +++ b/drivers/s390/cio/vfio_ccw_ops.c > @@ -129,6 +129,7 @@ static int vfio_ccw_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > private->sch->schid.ssid, > private->sch->schid.sch_no); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/s390/crypto/vfio_ap_ops.c > b/drivers/s390/crypto/vfio_ap_ops.c > index 5c0f53c6dde7..47df1c593c35 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -343,6 +343,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > list_add(&matrix_mdev->node, &matrix_dev->mdev_list); > mutex_unlock(&matrix_dev->lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.= c > index b558d4cfd082..724e9b9841d8 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -45,6 +45,12 @@ void mdev_set_drvdata(struct mdev_device *mdev, > void *data) } EXPORT_SYMBOL(mdev_set_drvdata); >=20 > +void mdev_set_class(struct mdev_device *mdev, u16 id) { > + mdev->class_id =3D id; > +} > +EXPORT_SYMBOL(mdev_set_class); > + Usually with every exported symbol we have signature comment block that des= cribes when to use an API etc. Please add it that describes that this API must be called during create() c= allback. > struct device *mdev_dev(struct mdev_device *mdev) { > return &mdev->dev; > @@ -135,6 +141,7 @@ static int mdev_device_remove_cb(struct device > *dev, void *data) > * mdev_register_device : Register a device > * @dev: device structure representing parent device. > * @ops: Parent device operation structure to be registered. > + * @id: class id. > * > * Add device to list of registered parent devices. > * Returns a negative value on error, otherwise 0. > @@ -324,6 +331,9 @@ int mdev_device_create(struct kobject *kobj, > if (ret) > goto ops_create_fail; >=20 > + if (!mdev->class_id) > + goto class_id_fail; > + > ret =3D device_add(&mdev->dev); > if (ret) > goto add_fail; > @@ -340,6 +350,7 @@ int mdev_device_create(struct kobject *kobj, >=20 > sysfs_fail: > device_del(&mdev->dev); > +class_id_fail: No need for new label. Just use add_fail label. > add_fail: > parent->ops->remove(mdev); > ops_create_fail: > diff --git a/drivers/vfio/mdev/mdev_driver.c > b/drivers/vfio/mdev/mdev_driver.c index 0d3223aee20b..b7c40ce86ee3 > 100644 > --- a/drivers/vfio/mdev/mdev_driver.c > +++ b/drivers/vfio/mdev/mdev_driver.c > @@ -69,8 +69,22 @@ static int mdev_remove(struct device *dev) > return 0; > } >=20 > +static int mdev_match(struct device *dev, struct device_driver *drv) { > + unsigned int i; > + struct mdev_device *mdev =3D to_mdev_device(dev); > + struct mdev_driver *mdrv =3D to_mdev_driver(drv); > + const struct mdev_class_id *ids =3D mdrv->id_table; > + > + for (i =3D 0; ids[i].id; i++) > + if (ids[i].id =3D=3D mdev->class_id) > + return 1; > + return 0; > +} > + > struct bus_type mdev_bus_type =3D { > .name =3D "mdev", > + .match =3D mdev_match, > .probe =3D mdev_probe, > .remove =3D mdev_remove, > }; > diff --git a/drivers/vfio/mdev/mdev_private.h > b/drivers/vfio/mdev/mdev_private.h > index 7d922950caaf..c65f436c1869 100644 > --- a/drivers/vfio/mdev/mdev_private.h > +++ b/drivers/vfio/mdev/mdev_private.h > @@ -33,6 +33,7 @@ struct mdev_device { > struct kobject *type_kobj; > struct device *iommu_device; > bool active; > + u16 class_id; > }; >=20 > #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) > diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.= c > index 30964a4e0a28..fd2a4d9a3f26 100644 > --- a/drivers/vfio/mdev/vfio_mdev.c > +++ b/drivers/vfio/mdev/vfio_mdev.c > @@ -120,10 +120,16 @@ static void vfio_mdev_remove(struct device *dev) > vfio_del_group_dev(dev); > } >=20 > +static struct mdev_class_id id_table[] =3D { static const=20 > + { MDEV_ID_VFIO }, I guess you don't need extra braces for each entry. Since this enum represents MDEV class id, it better to name it as MDEV_CLAS= S_ID_VFIO. (Similar to PCI_VENDOR_ID, PCI_DEVICE_ID).. > + { 0 }, > +}; > + > static struct mdev_driver vfio_mdev_driver =3D { > .name =3D "vfio_mdev", > .probe =3D vfio_mdev_probe, > .remove =3D vfio_mdev_remove, > + .id_table =3D id_table, > }; >=20 > static int __init vfio_mdev_init(void) > diff --git a/include/linux/mdev.h b/include/linux/mdev.h index > 0ce30ca78db0..a7570cf13ba4 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -118,6 +118,7 @@ struct mdev_type_attribute > mdev_type_attr_##_name =3D \ > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > * > **/ > struct mdev_driver { > @@ -125,12 +126,14 @@ struct mdev_driver { > int (*probe)(struct device *dev); > void (*remove)(struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > #define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver= ) >=20 > void *mdev_get_drvdata(struct mdev_device *mdev); void > mdev_set_drvdata(struct mdev_device *mdev, void *data); > +void mdev_set_class(struct mdev_device *mdev, u16 id); Better to insert new API after mdev_uuid(). > const guid_t *mdev_uuid(struct mdev_device *mdev); >=20 > extern struct bus_type mdev_bus_type; > @@ -145,4 +148,9 @@ struct device *mdev_parent_dev(struct mdev_device > *mdev); struct device *mdev_dev(struct mdev_device *mdev); struct > mdev_device *mdev_from_dev(struct device *dev); >=20 > +enum { > + MDEV_ID_VFIO =3D 1, > + /* New entries must be added here */ > +}; > + > #endif /* MDEV_H */ > diff --git a/include/linux/mod_devicetable.h > b/include/linux/mod_devicetable.h index 5714fd35a83c..f32c6e44fb1a > 100644 > --- a/include/linux/mod_devicetable.h > +++ b/include/linux/mod_devicetable.h > @@ -821,4 +821,12 @@ struct wmi_device_id { > const void *context; > }; >=20 > +/** > + * struct mdev_class_id - MDEV device class identifier > + * @id: Used to identify a specific class of device, e.g vfio-mdev devic= e. > + */ > +struct mdev_class_id { > + __u16 id; > +}; > + > #endif /* LINUX_MOD_DEVICETABLE_H */ > diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c > index ac5c8c17b1ff..fd8491e58fe2 100644 > --- a/samples/vfio-mdev/mbochs.c > +++ b/samples/vfio-mdev/mbochs.c > @@ -561,6 +561,7 @@ static int mbochs_create(struct kobject *kobj, struct > mdev_device *mdev) > mbochs_reset(mdev); >=20 > mbochs_used_mbytes +=3D type->mbytes; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; >=20 > err_mem: > diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index > cc86bf6566e4..889472b06708 100644 > --- a/samples/vfio-mdev/mdpy.c > +++ b/samples/vfio-mdev/mdpy.c > @@ -269,6 +269,7 @@ static int mdpy_create(struct kobject *kobj, struct > mdev_device *mdev) > mdpy_reset(mdev); >=20 > mdpy_count++; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c index > ce84a300a4da..618810ca4331 100644 > --- a/samples/vfio-mdev/mtty.c > +++ b/samples/vfio-mdev/mtty.c > @@ -755,6 +755,7 @@ static int mtty_create(struct kobject *kobj, struct > mdev_device *mdev) > list_add(&mdev_state->next, &mdev_devices_list); > mutex_unlock(&mdev_list_lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > -- > 2.19.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-eopbgr80044.outbound.protection.outlook.com ([40.107.8.44]:61253 "EHLO EUR04-VI1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2389668AbfJPE5m (ORCPT ); Wed, 16 Oct 2019 00:57:42 -0400 From: Parav Pandit Subject: RE: [PATCH V3 1/7] mdev: class id support Date: Wed, 16 Oct 2019 04:57:31 +0000 Message-ID: References: <20191011081557.28302-1-jasowang@redhat.com> <20191011081557.28302-2-jasowang@redhat.com> In-Reply-To: <20191011081557.28302-2-jasowang@redhat.com> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-s390-owner@vger.kernel.org List-ID: To: Jason Wang , "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" Cc: "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "cohuck@redhat.com" , "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" , Ido Shamay , "eperezma@redhat.com" , "lulu@redhat.com" , "christophe.de.dinechin@gmail.com" , "kevin.tian@intel.com" > -----Original Message----- > From: Jason Wang > Sent: Friday, October 11, 2019 3:16 AM > To: 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 > Cc: virtualization@lists.linux-foundation.org; netdev@vger.kernel.org; > cohuck@redhat.com; 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; Ido Shamay ; > eperezma@redhat.com; lulu@redhat.com; Parav Pandit > ; christophe.de.dinechin@gmail.com; > kevin.tian@intel.com; Jason Wang > Subject: [PATCH V3 1/7] mdev: class id support >=20 > Mdev bus only supports vfio driver right now, so it doesn't implement mat= ch > method. But in the future, we may add drivers other than vfio, the first > driver could be virtio-mdev. This means we need to add device class id > support in bus match method to pair the mdev device and mdev driver > correctly. >=20 > So this patch adds id_table to mdev_driver and class_id for mdev device > with the match method for mdev bus. >=20 > Signed-off-by: Jason Wang > --- > Documentation/driver-api/vfio-mediated-device.rst | 7 ++++++- > drivers/gpu/drm/i915/gvt/kvmgt.c | 1 + > drivers/s390/cio/vfio_ccw_ops.c | 1 + > drivers/s390/crypto/vfio_ap_ops.c | 1 + > drivers/vfio/mdev/mdev_core.c | 11 +++++++++++ > drivers/vfio/mdev/mdev_driver.c | 14 ++++++++++++++ > drivers/vfio/mdev/mdev_private.h | 1 + > drivers/vfio/mdev/vfio_mdev.c | 6 ++++++ > include/linux/mdev.h | 8 ++++++++ > include/linux/mod_devicetable.h | 8 ++++++++ > samples/vfio-mdev/mbochs.c | 1 + > samples/vfio-mdev/mdpy.c | 1 + > samples/vfio-mdev/mtty.c | 1 + > 13 files changed, 60 insertions(+), 1 deletion(-) >=20 > diff --git a/Documentation/driver-api/vfio-mediated-device.rst > b/Documentation/driver-api/vfio-mediated-device.rst > index 25eb7d5b834b..2035e48da7b2 100644 > --- a/Documentation/driver-api/vfio-mediated-device.rst > +++ b/Documentation/driver-api/vfio-mediated-device.rst > @@ -102,12 +102,14 @@ structure to represent a mediated device's driver:: > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > */ > struct mdev_driver { > const char *name; > int (*probe) (struct device *dev); > void (*remove) (struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > A mediated bus driver for mdev should use this structure in the function > calls @@ -165,12 +167,15 @@ register itself with the mdev core driver:: > extern int mdev_register_device(struct device *dev, > const struct mdev_parent_ops *ops); >=20 > +It is also required to specify the class_id through:: > + > + extern int mdev_set_class(struct device *dev, u16 id); Drop extern. In actual API you have correct signature, i.e. struct mdev_device. s/struct device/struct mdev_device. > + > However, the mdev_parent_ops structure is not required in the function c= all > that a driver should use to unregister itself with the mdev core driver:: >=20 > extern void mdev_unregister_device(struct device *dev); >=20 > - > Mediated Device Management Interface Through sysfs > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D >=20 > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c > b/drivers/gpu/drm/i915/gvt/kvmgt.c > index 343d79c1cb7e..17e9d4634c84 100644 > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c > @@ -678,6 +678,7 @@ static int intel_vgpu_create(struct kobject *kobj, > struct mdev_device *mdev) > dev_name(mdev_dev(mdev))); > ret =3D 0; >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > out: > return ret; > } > diff --git a/drivers/s390/cio/vfio_ccw_ops.c > b/drivers/s390/cio/vfio_ccw_ops.c index f0d71ab77c50..b5d223882c6c > 100644 > --- a/drivers/s390/cio/vfio_ccw_ops.c > +++ b/drivers/s390/cio/vfio_ccw_ops.c > @@ -129,6 +129,7 @@ static int vfio_ccw_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > private->sch->schid.ssid, > private->sch->schid.sch_no); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/s390/crypto/vfio_ap_ops.c > b/drivers/s390/crypto/vfio_ap_ops.c > index 5c0f53c6dde7..47df1c593c35 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -343,6 +343,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > list_add(&matrix_mdev->node, &matrix_dev->mdev_list); > mutex_unlock(&matrix_dev->lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.= c > index b558d4cfd082..724e9b9841d8 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -45,6 +45,12 @@ void mdev_set_drvdata(struct mdev_device *mdev, > void *data) } EXPORT_SYMBOL(mdev_set_drvdata); >=20 > +void mdev_set_class(struct mdev_device *mdev, u16 id) { > + mdev->class_id =3D id; > +} > +EXPORT_SYMBOL(mdev_set_class); > + Usually with every exported symbol we have signature comment block that des= cribes when to use an API etc. Please add it that describes that this API must be called during create() c= allback. > struct device *mdev_dev(struct mdev_device *mdev) { > return &mdev->dev; > @@ -135,6 +141,7 @@ static int mdev_device_remove_cb(struct device > *dev, void *data) > * mdev_register_device : Register a device > * @dev: device structure representing parent device. > * @ops: Parent device operation structure to be registered. > + * @id: class id. > * > * Add device to list of registered parent devices. > * Returns a negative value on error, otherwise 0. > @@ -324,6 +331,9 @@ int mdev_device_create(struct kobject *kobj, > if (ret) > goto ops_create_fail; >=20 > + if (!mdev->class_id) > + goto class_id_fail; > + > ret =3D device_add(&mdev->dev); > if (ret) > goto add_fail; > @@ -340,6 +350,7 @@ int mdev_device_create(struct kobject *kobj, >=20 > sysfs_fail: > device_del(&mdev->dev); > +class_id_fail: No need for new label. Just use add_fail label. > add_fail: > parent->ops->remove(mdev); > ops_create_fail: > diff --git a/drivers/vfio/mdev/mdev_driver.c > b/drivers/vfio/mdev/mdev_driver.c index 0d3223aee20b..b7c40ce86ee3 > 100644 > --- a/drivers/vfio/mdev/mdev_driver.c > +++ b/drivers/vfio/mdev/mdev_driver.c > @@ -69,8 +69,22 @@ static int mdev_remove(struct device *dev) > return 0; > } >=20 > +static int mdev_match(struct device *dev, struct device_driver *drv) { > + unsigned int i; > + struct mdev_device *mdev =3D to_mdev_device(dev); > + struct mdev_driver *mdrv =3D to_mdev_driver(drv); > + const struct mdev_class_id *ids =3D mdrv->id_table; > + > + for (i =3D 0; ids[i].id; i++) > + if (ids[i].id =3D=3D mdev->class_id) > + return 1; > + return 0; > +} > + > struct bus_type mdev_bus_type =3D { > .name =3D "mdev", > + .match =3D mdev_match, > .probe =3D mdev_probe, > .remove =3D mdev_remove, > }; > diff --git a/drivers/vfio/mdev/mdev_private.h > b/drivers/vfio/mdev/mdev_private.h > index 7d922950caaf..c65f436c1869 100644 > --- a/drivers/vfio/mdev/mdev_private.h > +++ b/drivers/vfio/mdev/mdev_private.h > @@ -33,6 +33,7 @@ struct mdev_device { > struct kobject *type_kobj; > struct device *iommu_device; > bool active; > + u16 class_id; > }; >=20 > #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) > diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.= c > index 30964a4e0a28..fd2a4d9a3f26 100644 > --- a/drivers/vfio/mdev/vfio_mdev.c > +++ b/drivers/vfio/mdev/vfio_mdev.c > @@ -120,10 +120,16 @@ static void vfio_mdev_remove(struct device *dev) > vfio_del_group_dev(dev); > } >=20 > +static struct mdev_class_id id_table[] =3D { static const=20 > + { MDEV_ID_VFIO }, I guess you don't need extra braces for each entry. Since this enum represents MDEV class id, it better to name it as MDEV_CLAS= S_ID_VFIO. (Similar to PCI_VENDOR_ID, PCI_DEVICE_ID).. > + { 0 }, > +}; > + > static struct mdev_driver vfio_mdev_driver =3D { > .name =3D "vfio_mdev", > .probe =3D vfio_mdev_probe, > .remove =3D vfio_mdev_remove, > + .id_table =3D id_table, > }; >=20 > static int __init vfio_mdev_init(void) > diff --git a/include/linux/mdev.h b/include/linux/mdev.h index > 0ce30ca78db0..a7570cf13ba4 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -118,6 +118,7 @@ struct mdev_type_attribute > mdev_type_attr_##_name =3D \ > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > * > **/ > struct mdev_driver { > @@ -125,12 +126,14 @@ struct mdev_driver { > int (*probe)(struct device *dev); > void (*remove)(struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > #define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver= ) >=20 > void *mdev_get_drvdata(struct mdev_device *mdev); void > mdev_set_drvdata(struct mdev_device *mdev, void *data); > +void mdev_set_class(struct mdev_device *mdev, u16 id); Better to insert new API after mdev_uuid(). > const guid_t *mdev_uuid(struct mdev_device *mdev); >=20 > extern struct bus_type mdev_bus_type; > @@ -145,4 +148,9 @@ struct device *mdev_parent_dev(struct mdev_device > *mdev); struct device *mdev_dev(struct mdev_device *mdev); struct > mdev_device *mdev_from_dev(struct device *dev); >=20 > +enum { > + MDEV_ID_VFIO =3D 1, > + /* New entries must be added here */ > +}; > + > #endif /* MDEV_H */ > diff --git a/include/linux/mod_devicetable.h > b/include/linux/mod_devicetable.h index 5714fd35a83c..f32c6e44fb1a > 100644 > --- a/include/linux/mod_devicetable.h > +++ b/include/linux/mod_devicetable.h > @@ -821,4 +821,12 @@ struct wmi_device_id { > const void *context; > }; >=20 > +/** > + * struct mdev_class_id - MDEV device class identifier > + * @id: Used to identify a specific class of device, e.g vfio-mdev devic= e. > + */ > +struct mdev_class_id { > + __u16 id; > +}; > + > #endif /* LINUX_MOD_DEVICETABLE_H */ > diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c > index ac5c8c17b1ff..fd8491e58fe2 100644 > --- a/samples/vfio-mdev/mbochs.c > +++ b/samples/vfio-mdev/mbochs.c > @@ -561,6 +561,7 @@ static int mbochs_create(struct kobject *kobj, struct > mdev_device *mdev) > mbochs_reset(mdev); >=20 > mbochs_used_mbytes +=3D type->mbytes; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; >=20 > err_mem: > diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index > cc86bf6566e4..889472b06708 100644 > --- a/samples/vfio-mdev/mdpy.c > +++ b/samples/vfio-mdev/mdpy.c > @@ -269,6 +269,7 @@ static int mdpy_create(struct kobject *kobj, struct > mdev_device *mdev) > mdpy_reset(mdev); >=20 > mdpy_count++; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c index > ce84a300a4da..618810ca4331 100644 > --- a/samples/vfio-mdev/mtty.c > +++ b/samples/vfio-mdev/mtty.c > @@ -755,6 +755,7 @@ static int mtty_create(struct kobject *kobj, struct > mdev_device *mdev) > list_add(&mdev_state->next, &mdev_devices_list); > mutex_unlock(&mdev_list_lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > -- > 2.19.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Parav Pandit Subject: RE: [PATCH V3 1/7] mdev: class id support Date: Wed, 16 Oct 2019 04:57:31 +0000 Message-ID: References: <20191011081557.28302-1-jasowang@redhat.com> <20191011081557.28302-2-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20191011081557.28302-2-jasowang@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Jason Wang , "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" Cc: "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "cohuck@redhat.com" , "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" List-Id: dri-devel@lists.freedesktop.org > -----Original Message----- > From: Jason Wang > Sent: Friday, October 11, 2019 3:16 AM > To: 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 > Cc: virtualization@lists.linux-foundation.org; netdev@vger.kernel.org; > cohuck@redhat.com; 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; Ido Shamay ; > eperezma@redhat.com; lulu@redhat.com; Parav Pandit > ; christophe.de.dinechin@gmail.com; > kevin.tian@intel.com; Jason Wang > Subject: [PATCH V3 1/7] mdev: class id support >=20 > Mdev bus only supports vfio driver right now, so it doesn't implement mat= ch > method. But in the future, we may add drivers other than vfio, the first > driver could be virtio-mdev. This means we need to add device class id > support in bus match method to pair the mdev device and mdev driver > correctly. >=20 > So this patch adds id_table to mdev_driver and class_id for mdev device > with the match method for mdev bus. >=20 > Signed-off-by: Jason Wang > --- > Documentation/driver-api/vfio-mediated-device.rst | 7 ++++++- > drivers/gpu/drm/i915/gvt/kvmgt.c | 1 + > drivers/s390/cio/vfio_ccw_ops.c | 1 + > drivers/s390/crypto/vfio_ap_ops.c | 1 + > drivers/vfio/mdev/mdev_core.c | 11 +++++++++++ > drivers/vfio/mdev/mdev_driver.c | 14 ++++++++++++++ > drivers/vfio/mdev/mdev_private.h | 1 + > drivers/vfio/mdev/vfio_mdev.c | 6 ++++++ > include/linux/mdev.h | 8 ++++++++ > include/linux/mod_devicetable.h | 8 ++++++++ > samples/vfio-mdev/mbochs.c | 1 + > samples/vfio-mdev/mdpy.c | 1 + > samples/vfio-mdev/mtty.c | 1 + > 13 files changed, 60 insertions(+), 1 deletion(-) >=20 > diff --git a/Documentation/driver-api/vfio-mediated-device.rst > b/Documentation/driver-api/vfio-mediated-device.rst > index 25eb7d5b834b..2035e48da7b2 100644 > --- a/Documentation/driver-api/vfio-mediated-device.rst > +++ b/Documentation/driver-api/vfio-mediated-device.rst > @@ -102,12 +102,14 @@ structure to represent a mediated device's driver:: > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > */ > struct mdev_driver { > const char *name; > int (*probe) (struct device *dev); > void (*remove) (struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > A mediated bus driver for mdev should use this structure in the function > calls @@ -165,12 +167,15 @@ register itself with the mdev core driver:: > extern int mdev_register_device(struct device *dev, > const struct mdev_parent_ops *ops); >=20 > +It is also required to specify the class_id through:: > + > + extern int mdev_set_class(struct device *dev, u16 id); Drop extern. In actual API you have correct signature, i.e. struct mdev_device. s/struct device/struct mdev_device. > + > However, the mdev_parent_ops structure is not required in the function c= all > that a driver should use to unregister itself with the mdev core driver:: >=20 > extern void mdev_unregister_device(struct device *dev); >=20 > - > Mediated Device Management Interface Through sysfs > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D >=20 > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c > b/drivers/gpu/drm/i915/gvt/kvmgt.c > index 343d79c1cb7e..17e9d4634c84 100644 > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c > @@ -678,6 +678,7 @@ static int intel_vgpu_create(struct kobject *kobj, > struct mdev_device *mdev) > dev_name(mdev_dev(mdev))); > ret =3D 0; >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > out: > return ret; > } > diff --git a/drivers/s390/cio/vfio_ccw_ops.c > b/drivers/s390/cio/vfio_ccw_ops.c index f0d71ab77c50..b5d223882c6c > 100644 > --- a/drivers/s390/cio/vfio_ccw_ops.c > +++ b/drivers/s390/cio/vfio_ccw_ops.c > @@ -129,6 +129,7 @@ static int vfio_ccw_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > private->sch->schid.ssid, > private->sch->schid.sch_no); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/s390/crypto/vfio_ap_ops.c > b/drivers/s390/crypto/vfio_ap_ops.c > index 5c0f53c6dde7..47df1c593c35 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -343,6 +343,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > list_add(&matrix_mdev->node, &matrix_dev->mdev_list); > mutex_unlock(&matrix_dev->lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.= c > index b558d4cfd082..724e9b9841d8 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -45,6 +45,12 @@ void mdev_set_drvdata(struct mdev_device *mdev, > void *data) } EXPORT_SYMBOL(mdev_set_drvdata); >=20 > +void mdev_set_class(struct mdev_device *mdev, u16 id) { > + mdev->class_id =3D id; > +} > +EXPORT_SYMBOL(mdev_set_class); > + Usually with every exported symbol we have signature comment block that des= cribes when to use an API etc. Please add it that describes that this API must be called during create() c= allback. > struct device *mdev_dev(struct mdev_device *mdev) { > return &mdev->dev; > @@ -135,6 +141,7 @@ static int mdev_device_remove_cb(struct device > *dev, void *data) > * mdev_register_device : Register a device > * @dev: device structure representing parent device. > * @ops: Parent device operation structure to be registered. > + * @id: class id. > * > * Add device to list of registered parent devices. > * Returns a negative value on error, otherwise 0. > @@ -324,6 +331,9 @@ int mdev_device_create(struct kobject *kobj, > if (ret) > goto ops_create_fail; >=20 > + if (!mdev->class_id) > + goto class_id_fail; > + > ret =3D device_add(&mdev->dev); > if (ret) > goto add_fail; > @@ -340,6 +350,7 @@ int mdev_device_create(struct kobject *kobj, >=20 > sysfs_fail: > device_del(&mdev->dev); > +class_id_fail: No need for new label. Just use add_fail label. > add_fail: > parent->ops->remove(mdev); > ops_create_fail: > diff --git a/drivers/vfio/mdev/mdev_driver.c > b/drivers/vfio/mdev/mdev_driver.c index 0d3223aee20b..b7c40ce86ee3 > 100644 > --- a/drivers/vfio/mdev/mdev_driver.c > +++ b/drivers/vfio/mdev/mdev_driver.c > @@ -69,8 +69,22 @@ static int mdev_remove(struct device *dev) > return 0; > } >=20 > +static int mdev_match(struct device *dev, struct device_driver *drv) { > + unsigned int i; > + struct mdev_device *mdev =3D to_mdev_device(dev); > + struct mdev_driver *mdrv =3D to_mdev_driver(drv); > + const struct mdev_class_id *ids =3D mdrv->id_table; > + > + for (i =3D 0; ids[i].id; i++) > + if (ids[i].id =3D=3D mdev->class_id) > + return 1; > + return 0; > +} > + > struct bus_type mdev_bus_type =3D { > .name =3D "mdev", > + .match =3D mdev_match, > .probe =3D mdev_probe, > .remove =3D mdev_remove, > }; > diff --git a/drivers/vfio/mdev/mdev_private.h > b/drivers/vfio/mdev/mdev_private.h > index 7d922950caaf..c65f436c1869 100644 > --- a/drivers/vfio/mdev/mdev_private.h > +++ b/drivers/vfio/mdev/mdev_private.h > @@ -33,6 +33,7 @@ struct mdev_device { > struct kobject *type_kobj; > struct device *iommu_device; > bool active; > + u16 class_id; > }; >=20 > #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) > diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.= c > index 30964a4e0a28..fd2a4d9a3f26 100644 > --- a/drivers/vfio/mdev/vfio_mdev.c > +++ b/drivers/vfio/mdev/vfio_mdev.c > @@ -120,10 +120,16 @@ static void vfio_mdev_remove(struct device *dev) > vfio_del_group_dev(dev); > } >=20 > +static struct mdev_class_id id_table[] =3D { static const=20 > + { MDEV_ID_VFIO }, I guess you don't need extra braces for each entry. Since this enum represents MDEV class id, it better to name it as MDEV_CLAS= S_ID_VFIO. (Similar to PCI_VENDOR_ID, PCI_DEVICE_ID).. > + { 0 }, > +}; > + > static struct mdev_driver vfio_mdev_driver =3D { > .name =3D "vfio_mdev", > .probe =3D vfio_mdev_probe, > .remove =3D vfio_mdev_remove, > + .id_table =3D id_table, > }; >=20 > static int __init vfio_mdev_init(void) > diff --git a/include/linux/mdev.h b/include/linux/mdev.h index > 0ce30ca78db0..a7570cf13ba4 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -118,6 +118,7 @@ struct mdev_type_attribute > mdev_type_attr_##_name =3D \ > * @probe: called when new device created > * @remove: called when device removed > * @driver: device driver structure > + * @id_table: the ids serviced by this driver > * > **/ > struct mdev_driver { > @@ -125,12 +126,14 @@ struct mdev_driver { > int (*probe)(struct device *dev); > void (*remove)(struct device *dev); > struct device_driver driver; > + const struct mdev_class_id *id_table; > }; >=20 > #define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver= ) >=20 > void *mdev_get_drvdata(struct mdev_device *mdev); void > mdev_set_drvdata(struct mdev_device *mdev, void *data); > +void mdev_set_class(struct mdev_device *mdev, u16 id); Better to insert new API after mdev_uuid(). > const guid_t *mdev_uuid(struct mdev_device *mdev); >=20 > extern struct bus_type mdev_bus_type; > @@ -145,4 +148,9 @@ struct device *mdev_parent_dev(struct mdev_device > *mdev); struct device *mdev_dev(struct mdev_device *mdev); struct > mdev_device *mdev_from_dev(struct device *dev); >=20 > +enum { > + MDEV_ID_VFIO =3D 1, > + /* New entries must be added here */ > +}; > + > #endif /* MDEV_H */ > diff --git a/include/linux/mod_devicetable.h > b/include/linux/mod_devicetable.h index 5714fd35a83c..f32c6e44fb1a > 100644 > --- a/include/linux/mod_devicetable.h > +++ b/include/linux/mod_devicetable.h > @@ -821,4 +821,12 @@ struct wmi_device_id { > const void *context; > }; >=20 > +/** > + * struct mdev_class_id - MDEV device class identifier > + * @id: Used to identify a specific class of device, e.g vfio-mdev devic= e. > + */ > +struct mdev_class_id { > + __u16 id; > +}; > + > #endif /* LINUX_MOD_DEVICETABLE_H */ > diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c > index ac5c8c17b1ff..fd8491e58fe2 100644 > --- a/samples/vfio-mdev/mbochs.c > +++ b/samples/vfio-mdev/mbochs.c > @@ -561,6 +561,7 @@ static int mbochs_create(struct kobject *kobj, struct > mdev_device *mdev) > mbochs_reset(mdev); >=20 > mbochs_used_mbytes +=3D type->mbytes; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; >=20 > err_mem: > diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index > cc86bf6566e4..889472b06708 100644 > --- a/samples/vfio-mdev/mdpy.c > +++ b/samples/vfio-mdev/mdpy.c > @@ -269,6 +269,7 @@ static int mdpy_create(struct kobject *kobj, struct > mdev_device *mdev) > mdpy_reset(mdev); >=20 > mdpy_count++; > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c index > ce84a300a4da..618810ca4331 100644 > --- a/samples/vfio-mdev/mtty.c > +++ b/samples/vfio-mdev/mtty.c > @@ -755,6 +755,7 @@ static int mtty_create(struct kobject *kobj, struct > mdev_device *mdev) > list_add(&mdev_state->next, &mdev_devices_list); > mutex_unlock(&mdev_list_lock); >=20 > + mdev_set_class(mdev, MDEV_ID_VFIO); > return 0; > } >=20 > -- > 2.19.1