On Thu, Sep 09 2021, Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > Many of the mdev drivers use a simple counter for keeping track of the > available instances. Move this code to the core code and store the counter > in the mdev_type. Implement it using correct locking, fixing mdpy. > > Drivers provide a get_available() callback to set the number of available > instances for their mtypes which is fixed at registration time. The core > provides a standard sysfs attribute to return the available_instances. So, according to the documentation, available_instances is mandatory. This means that drivers either need to provide get_available or implement their own version of the attribute. I think we want to update vfio-mediated-device.rst as well? > > Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > --- > drivers/s390/cio/vfio_ccw_drv.c | 1 - > drivers/s390/cio/vfio_ccw_ops.c | 26 ++++++------------- > drivers/s390/cio/vfio_ccw_private.h | 2 -- > drivers/s390/crypto/vfio_ap_ops.c | 32 ++++++----------------- > drivers/s390/crypto/vfio_ap_private.h | 2 -- > drivers/vfio/mdev/mdev_core.c | 11 +++++++- > drivers/vfio/mdev/mdev_private.h | 2 ++ > drivers/vfio/mdev/mdev_sysfs.c | 37 +++++++++++++++++++++++++++ > include/linux/mdev.h | 2 ++ > samples/vfio-mdev/mdpy.c | 22 +++++----------- > 10 files changed, 73 insertions(+), 64 deletions(-) Otherwise, looks good.