On Tue, 5 Nov 2019 17:32:37 +0800 Jason Wang <jasowang@xxxxxxxxxx> 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. > > Reviewed-by: Parav Pandit <parav@xxxxxxxxxxxx> > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> > --- > .../driver-api/vfio-mediated-device.rst | 35 +++++++++---- > 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 | 24 ++++++++- > drivers/vfio/mdev/mdev_private.h | 5 ++ > drivers/vfio/mdev/vfio_mdev.c | 37 ++++++------- > include/linux/mdev.h | 43 ++++----------- > include/linux/mdev_vfio_ops.h | 52 +++++++++++++++++++ > samples/vfio-mdev/mbochs.c | 20 ++++--- > samples/vfio-mdev/mdpy.c | 20 ++++--- > samples/vfio-mdev/mtty.c | 18 ++++--- > 13 files changed, 206 insertions(+), 99 deletions(-) > create mode 100644 include/linux/mdev_vfio_ops.h > (...) > @@ -172,10 +163,34 @@ 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:: > +As multiple types of mediated devices may be supported, class id needs > +to be specified in the create callback(). This could be done The brackets should probably go behind 'create'? > +explicitly for the device that does not use on mdev bus for its "for devices that do not use the mdev bus" ? But why wouldn't they? I feel like I've missed some discussion here :/ > +operation through: > > int mdev_set_class(struct mdev_device *mdev, u16 id); > > +For the device that uses on the mdev bus for its operation, the class "For devices that use the mdev bus..." But same comment as above. > +should provide helper function to set class id and device specific > +ops. E.g for vfio-mdev devices, the function to be called is:: > + > + int mdev_set_vfio_ops(struct mdev_device *mdev, > + const struct mdev_vfio_device_ops *vfio_ops); > + > +The class id (set by this function to MDEV_CLASS_ID_VFIO) is used to > +match a device with an mdev driver via its id table. The device > +specific callbacks (specified in *vfio_ops) are obtainable via > +mdev_get_vfio_ops() (for use by the mdev bus driver). A vfio-mdev > +device (class id MDEV_CLASS_ID_VFIO) uses the following > +device-specific ops: > + > +* 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 > + > Mediated Device Management Interface Through sysfs > ================================================== Otherwise, looks good.
