On Mon, 18 Feb 2019 19:08:48 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
> Libudev relies on having a subsystem link for non-root devices. To
> avoid libudev (and potentially other userspace tools) choking on the
> matrix device let us introduce a vfio_ap bus and with that the vfio_ap
> bus subsytem, and make the matrix device reside within it.
>
> Doing this we need to suppress the forced link from the matrix device to
> the vfio_ap driver and we suppress the device_type we do not need
> anymore.
>
> Since the associated matrix driver is not the vfio_ap driver any more,
> we have to change the search for the devices on the vfio_ap driver in
> the function vfio_ap_verify_queue_reserved.
>
> Reported-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx>
> Reported-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
> drivers/s390/crypto/vfio_ap_drv.c | 48 +++++++++++++++++++++++++++++------
> drivers/s390/crypto/vfio_ap_ops.c | 4 +--
> drivers/s390/crypto/vfio_ap_private.h | 1 +
> 3 files changed, 43 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
> index 31c6c84..8e45559 100644
> --- a/drivers/s390/crypto/vfio_ap_drv.c
> +++ b/drivers/s390/crypto/vfio_ap_drv.c
> @@ -24,10 +24,6 @@ MODULE_LICENSE("GPL v2");
>
> static struct ap_driver vfio_ap_drv;
>
> -static struct device_type vfio_ap_dev_type = {
> - .name = VFIO_AP_DEV_TYPE_NAME,
> -};
> -
Would have been nice had you mentioned this in the commit message --
vfio_ap_dev_type was useless. And you should have removed
the define of VFIO_AP_DEV_TYPE_NAME a couple of lines above this.
> struct ap_matrix_dev *matrix_dev;
>
> /* Only type 10 adapters (CEX4 and later) are supported
> @@ -62,6 +58,27 @@ static void vfio_ap_matrix_dev_release(struct device *dev)
> kfree(matrix_dev);
> }
>
> +static int matrix_bus_match(struct device *dev, struct device_driver *drv)
> +{
> + return 1;
> +}
> +
> +static struct bus_type matrix_bus = {
> + .name = "vfio_ap",
> + .match = &matrix_bus_match,
> +};
> +
> +static int matrix_probe(struct device *dev)
> +{
> + return 0;
> +}
> +
> +static struct device_driver matrix_driver = {
> + .name = "vfio_ap",
> + .bus = &matrix_bus,
> + .probe = matrix_probe,
> +};
> +
With the changes suggested by Christian:
Acked-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
[..]
