Mdev bus only supports vfio driver right now, so it doesn't implement
match 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.
So this patch adds id_table to mdev_driver and class_id for mdev
device with the match method for mdev bus.
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
.../driver-api/vfio-mediated-device.rst | 5 +++++
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 | 18 +++++++++++++++
drivers/vfio/mdev/mdev_driver.c | 22 +++++++++++++++++++
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, 74 insertions(+)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 25eb7d5b834b..6709413bee29 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;
};
A mediated bus driver for mdev should use this structure in the function calls
@@ -170,6 +172,9 @@ that a driver should use to unregister itself with the mdev core driver::
extern void mdev_unregister_device(struct device *dev);
+It is also required to specify the class_id in create() callback through::
+
+ int mdev_set_class(struct mdev_device *mdev, u16 id);
Mediated Device Management Interface Through sysfs
==================================================
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 343d79c1cb7e..6420f0dbd31b 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 = 0;
+ mdev_set_class(mdev, MDEV_CLASS_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..cf2c013ae32f 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);
+ mdev_set_class(mdev, MDEV_CLASS_ID_VFIO);
return 0;
}
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 5c0f53c6dde7..07c31070afeb 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);
+ mdev_set_class(mdev, MDEV_CLASS_ID_VFIO);
return 0;
}
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index b558d4cfd082..3a9c52d71b4e 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -45,6 +45,16 @@ void mdev_set_drvdata(struct mdev_device *mdev, void *data)
}
EXPORT_SYMBOL(mdev_set_drvdata);
+/* Specify the class for the mdev device, this must be called during
+ * create() callback.
+ */
+void mdev_set_class(struct mdev_device *mdev, u16 id)
+{
+ WARN_ON(mdev->class_id);
+ mdev->class_id = id;
+}
+EXPORT_SYMBOL(mdev_set_class);
+
struct device *mdev_dev(struct mdev_device *mdev)
{
return &mdev->dev;
@@ -135,6 +145,7 @@ 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 +335,13 @@ int mdev_device_create(struct kobject *kobj,
if (ret)
goto ops_create_fail;
+ if (!mdev->class_id) {
+ ret = -EINVAL;
+ WARN(1, "class id must be specified for device %s\n",
+ dev_name(dev));
