[PATCH v3 5/9] s390: ap: tools to associate a queue to a matrix

Pierre Morel
2019-02-14T13:52:13Z

We need tools to associate a queue and a matrix to be able
later to find the matrix associated with the queue for which
we got the APQN in the register 1 during a PQAP/AQIC instruction
interception.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
drivers/s390/crypto/vfio_ap_ops.c | 66 +++++++++++++++++++++++++++++++++--
drivers/s390/crypto/vfio_ap_private.h | 1 +
2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 2a52c9b..1851b24 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -50,8 +50,7 @@ static int vfio_ap_check_apqn(struct device *dev, void *data)
*
* Returns the pointer to the associated vfio_ap_queue
*/
-static __attribute__((unused))
- struct vfio_ap_queue *vfio_ap_get_queue(int apqn)
+static struct vfio_ap_queue *vfio_ap_get_queue(int apqn)
{
struct device *dev;
struct vfio_ap_queue *q;
@@ -72,7 +71,7 @@ static __attribute__((unused))
* put the associated device
*
*/
-static __attribute__((unused)) void vfio_ap_put_queue(struct vfio_ap_queue *q)
+static void vfio_ap_put_queue(struct vfio_ap_queue *q)
{
put_device(q->dev);
q->dev = NULL;
@@ -867,6 +866,67 @@ static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
return -EBUSY;
}

+/**
+ * vfio_ap_dissociate_queues: Dissociate a matrix mediated device to a queue
+ *
+ * Go through all bits in the AQM and APM and dissociate the queue
+ * from the matrix device.
+ *
+ * No return value we are throwing the mediated device anyway.
+ */
+static void vfio_ap_dissociate_queues(struct ap_matrix_mdev *matrix_mdev)
+{
+ unsigned long apid, apqi;
+ struct vfio_ap_queue *q;
+
+ for_each_set_bit_inv(apid, matrix_mdev->matrix.apm,
+ matrix_mdev->matrix.apm_max + 1) {
+ for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
+ matrix_mdev->matrix.aqm_max + 1) {
+ q = vfio_ap_get_queue(AP_MKQID(apid, apqi));
+ if (q) {
+ vfio_ap_mdev_reset_queue(apid, apqi, 1);
+ q->matrix = NULL;
+ vfio_ap_put_queue(q);
+ } else
+ pr_err("%s: no queue for %02lx.%04lx\n",
+ __func__, apid, apqi);
+ }
+ }
+}
+
+/**
+ * vfio_ap_associate_queues: Associate a matrix mediated device to a queue
+ *
+ * Go through all bits in the AQM and APM and calculate the APQN, and find
+ * the matching queue to associate with the matrix device.
+ *
+ * In the case a queue could not be found return -ENODEV.
+ * Otherwise return 0.
+ */
+static __attribute__((unused))
+ int vfio_ap_associate_queues(struct ap_matrix_mdev *matrix_mdev)
+{
+ unsigned long apid, apqi;
+ struct vfio_ap_queue *q;
+
+ for_each_set_bit_inv(apid, matrix_mdev->matrix.apm,
+ matrix_mdev->matrix.apm_max + 1) {
+ for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
+ matrix_mdev->matrix.aqm_max + 1) {
+ q = vfio_ap_get_queue(AP_MKQID(apid, apqi));
+ if (!q)
+ goto error;
+ q->matrix = matrix_mdev;
+ vfio_ap_put_queue(q);
+ }
+ }
+ return 0;
+error:
+ pr_err("%s: no queue for %02lx.%04lx\n", __func__, apid, apqi);
+ vfio_ap_dissociate_queues(matrix_mdev);
+ return -ENODEV;
+}
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev)
{
int ret;
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index 081f0d7..10bc8b5 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -89,5 +89,6 @@ extern void vfio_ap_mdev_unregister(void);
struct vfio_ap_queue {
struct device *dev;
int apqn;
+ struct ap_matrix_mdev *matrix;
};
#endif /* _VFIO_AP_PRIVATE_H_ */
--
2.7.4