Let's implement the callback to indicate when an APQN is in use by the vfio_ap device driver. The callback is invoked whenever a change to the apmask or aqmask may result in one or APQNs being removed from the driver. The vfio_ap device driver will indicate a resource is in use if any of the removed APQNs are assigned to any of the matrix mdev devices. Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> --- drivers/s390/crypto/vfio_ap_drv.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c index e9824c35c34f..f340a28c1d65 100644 --- a/drivers/s390/crypto/vfio_ap_drv.c +++ b/drivers/s390/crypto/vfio_ap_drv.c @@ -139,6 +139,28 @@ static void vfio_ap_matrix_dev_destroy(void) root_device_unregister(root_device); } +static bool vfio_ap_resource_in_use(unsigned long *apm, unsigned long *aqm) +{ + bool in_use = false; + struct ap_matrix_mdev *matrix_mdev; + + mutex_lock(&matrix_dev->lock); + + list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) { + if (bitmap_intersects(matrix_mdev->matrix.apm, + apm, AP_DEVICES) && + bitmap_intersects(matrix_mdev->matrix.aqm, + aqm, AP_DOMAINS)) { + in_use = true; + break; + } + } + + mutex_unlock(&matrix_dev->lock); + + return in_use; +} + static int __init vfio_ap_init(void) { int ret; @@ -154,6 +176,7 @@ static int __init vfio_ap_init(void) memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); vfio_ap_drv.probe = vfio_ap_queue_dev_probe; vfio_ap_drv.remove = vfio_ap_queue_dev_remove; + vfio_ap_drv.in_use = vfio_ap_resource_in_use; vfio_ap_drv.ids = ap_queue_ids; ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); -- 2.7.4