[PATCH 3/3] s390/vfio-ap: Wire in the vfio_device_ops request callback

Tony Krowiak
2023-05-30T22:35:50Z

The mdev device is being removed, so pass the request to userspace to
ask for a graceful cleanup. This should free up the thread that
would otherwise loop waiting for the device to be fully released.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
---
drivers/s390/crypto/vfio_ap_ops.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 44f159136891..a8f58e133e6e 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -1736,6 +1736,26 @@ static void vfio_ap_mdev_close_device(struct vfio_device *vdev)
vfio_ap_mdev_unset_kvm(matrix_mdev);
}

+static void vfio_ap_mdev_request(struct vfio_device *vdev, unsigned int count)
+{
+ struct device *dev = vdev->dev;
+ struct ap_matrix_mdev *matrix_mdev;
+
+ matrix_mdev = container_of(vdev, struct ap_matrix_mdev, vdev);
+
+ if (matrix_mdev->req_trigger) {
+ if (!(count % 10))
+ dev_notice_ratelimited(dev,
+ "Relaying device request to user (#%u)\n",
+ count);
+
+ eventfd_signal(matrix_mdev->req_trigger, 1);
+ } else if (count == 0) {
+ dev_notice(dev,
+ "No device request registered, blocked until released by user\n");
+ }
+}
+
static int vfio_ap_mdev_get_device_info(unsigned long arg)
{
unsigned long minsz;
@@ -1955,6 +1975,7 @@ static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
.bind_iommufd = vfio_iommufd_emulated_bind,
.unbind_iommufd = vfio_iommufd_emulated_unbind,
.attach_ioas = vfio_iommufd_emulated_attach_ioas,
+ .request = vfio_ap_mdev_request
};

static struct mdev_driver vfio_ap_matrix_driver = {
--
2.31.1