+static inline int cmp_pgid(struct pgid *p1, struct pgid *p2)
+{
+ char *c1;
+ char *c2;
+
+ c1 = (char *)p1;
+ c2 = (char *)p2;
+
+ return memcmp(c1 + 1, c2 + 1, sizeof(struct pgid) - 1);
+}
+
+static void __ccw_device_get_common_pgid(struct ccw_device *cdev)
+{
+ int i;
+ int last;
+
+ last = 0;
+ for (i = 0; i < 8; i++) {
+ if (cdev->private->pgid[i].inf.ps.state1 == SNID_STATE1_RESET)
+ /* No PGID yet */
+ continue;
+ if (cdev->private->pgid[last].inf.ps.state1 ==
+ SNID_STATE1_RESET) {
+ /* First non-zero PGID */
+ last = i;
+ continue;
+ }
+ if (cmp_pgid(&cdev->private->pgid[i],
+ &cdev->private->pgid[last]) == 0)
+ /* Non-conflicting PGIDs */
+ continue;
+
+ /* PGID mismatch, can't pathgroup. */
+ CIO_MSG_EVENT(0, "SNID - pgid mismatch for device "
+ "0.%x.%04x, can't pathgroup\n",
+ cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno);
+ cdev->private->options.pgroup = 0;
+ return;
+ }
+ if (cdev->private->pgid[last].inf.ps.state1 ==
+ SNID_STATE1_RESET)
+ /* No previous pgid found */
+ memcpy(&cdev->private->pgid[0], &css[0]->global_pgid,
+ sizeof(struct pgid));
+ else
+ /* Use existing pgid */
+ memcpy(&cdev->private->pgid[0], &cdev->private->pgid[last],
+ sizeof(struct pgid));
+}
+