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).
+ 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 noninverse 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);
}
[..]