On 3/3/19 9:09 PM, Halil Pasic wrote:
On Fri, 22 Feb 2019 16:29:56 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
We need to associate the ap_vfio_queue, which will hold the
per queue information for interrupt with a matrix mediated device
which hold the configuration and the way to the CRYCB.
[..]
+static int vfio_ap_get_all_domains(struct ap_matrix_mdev *matrix_mdev, int apid)
+{
+ int apqi, apqn;
+ int ret = 0;
+ struct vfio_ap_queue *q;
+ struct list_head q_list;
+
+ INIT_LIST_HEAD(&q_list);
+
+ for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) {
+ apqn = AP_MKQID(apid, apqi);
+ q = vfio_ap_get_queue(apqn, &matrix_dev->free_list);
+ if (!q) {
+ ret = -EADDRNOTAVAIL;
+ goto rewind;
+ }
+ if (q->matrix_mdev) {
+ ret = -EADDRINUSE;
You tried to get the q from matrix_dev->free_list thus modulo races
q->matrix_mdev should be 0. This change breaks the error codes in a
sense that it becomes impossible to provoke EADDRINUSE (the proper
error code for taken by another matrix_mdev).
It is necessary to determine if the queue is in use by another mdev, so
it will still be necessary to traverse all of the matrix_mdev structs to
see if q is in matrix_mdev->qlist. It seems that maintaining the qlist
does not buy us much.
+ goto rewind;
+ }
+ list_move(&q->list, &q_list);
+ }
+ move_and_set(&q_list, &matrix_mdev->qlist, matrix_mdev);
return 0;
+rewind:
+ move_and_set(&q_list, &matrix_dev->free_list, NULL);
+ return ret;
}
-
/**
- * vfio_ap_mdev_verify_no_sharing
+ * vfio_ap_get_all_cards:
*
- * Verifies that the APQNs derived from the cross product of the AP adapter IDs
- * and AP queue indexes comprising the AP matrix are not configured for another
- * mediated device. AP queue sharing is not allowed.
+ * @matrix_mdev: the matrix mediated device for which we want to associate
+ * all available queues with a given apqi.
+ * @apqi: The apqi which associated with all defined APID of the
+ * mediated device will define a AP queue.
*
- * @matrix_mdev: the mediated matrix device
+ * We define a local list to put all queues we find on the matrix device
+ * free list when associating the apqi with all already defined apid for
+ * this matrix mediated device.
*
- * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE.
+ * If we can get all the devices we roll them to the mediated device list
+ * If we get errors we unroll them to the free list.
*/
-static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev)
+static int vfio_ap_get_all_cards(struct ap_matrix_mdev *matrix_mdev, int apqi)
{
- struct ap_matrix_mdev *lstdev;
- DECLARE_BITMAP(apm, AP_DEVICES);
- DECLARE_BITMAP(aqm, AP_DOMAINS);
-
- list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) {
- if (matrix_mdev == lstdev)
- continue;
-
- memset(apm, 0, sizeof(apm));
- memset(aqm, 0, sizeof(aqm));
-
- /*
- * We work on full longs, as we can only exclude the leftover
- * bits in non-inverse order. The leftover is all zeros.
- */
- if (!bitmap_and(apm, matrix_mdev->matrix.apm,
- lstdev->matrix.apm, AP_DEVICES))
- continue;
-
- if (!bitmap_and(aqm, matrix_mdev->matrix.aqm,
- lstdev->matrix.aqm, AP_DOMAINS))
- continue;
-
- return -EADDRINUSE;
+ int apid, apqn;
+ int ret = 0;
+ struct vfio_ap_queue *q;
+ struct list_head q_list;
+ struct ap_matrix_mdev *tmp = NULL;
+
+ INIT_LIST_HEAD(&q_list);
+
+ for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
+ apqn = AP_MKQID(apid, apqi);
+ q = vfio_ap_get_queue(apqn, &matrix_dev->free_list);
+ if (!q) {
+ ret = -EADDRNOTAVAIL;
+ goto rewind;
+ }
+ if (q->matrix_mdev) {
+ ret = -EADDRINUSE;
Same here!
Regards,
Halil
+ goto rewind;
+ }
+ list_move(&q->list, &q_list);
}
[..]
