On 2019/10/15 下午6:26, Cornelia Huck wrote:
On Fri, 11 Oct 2019 16:15:51 +0800
Jason Wang <jasowang@xxxxxxxxxx> wrote:
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>
---
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(-)
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;
};
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);
+It is also required to specify the class_id through::
+
+ extern int mdev_set_class(struct device *dev, u16 id);
Should the document state explicitly that this should be done in the
->create() callback?
Yes, it's better.
Also, I think that the class_id might be different
for different mdevs (even if the parent is the same) -- should that be
mentioned explicitly?
Yes, depends on the mdev_supported_type.
Thanks
+
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::
extern void mdev_unregister_device(struct device *dev);
-
Mediated Device Management Interface Through sysfs
==================================================
(...)
Looks reasonable to me.
