+ * This function determines the scope of a reconfiguration request by
+ * analysing the path and device selection data provided in the CUIR request.
+ * Returns a path mask containing CUIR affected paths for the give device.
+ *
+ * If the CUIR request does not contain the required information return the
+ * path mask of the path the attention message for the CUIR request was reveived
+ * on.
+ */
+static int dasd_eckd_cuir_scope(struct dasd_device *device, __u8 lpum,
+ struct dasd_cuir_message *cuir)
+{
+ struct dasd_conf_data *ref_conf_data;
+ unsigned long bitmask = 0, mask = 0;
+ struct dasd_eckd_private *private;
+ struct dasd_conf_data *conf_data;
+ unsigned int pos, path;
+ char *ref_gneq, *gneq;
+ char *ref_ned, *ned;
+ int tbcpm = 0;
+
+ /* if CUIR request does not specify the scope use the path
+ the attention message was presented on */
+ if (!cuir->ned_map ||
+ !(cuir->neq_map[0] | cuir->neq_map[1] | cuir->neq_map[2]))
+ return lpum;
+
+ private = (struct dasd_eckd_private *) device->private;
+ /* get reference conf data */
+ ref_conf_data = dasd_eckd_get_ref_conf(device, lpum, cuir);
+ /* reference ned is determined by ned_map field */
+ pos = 8 - ffs(cuir->ned_map);
+ ref_ned = (char *)&ref_conf_data->neds[pos];
+ ref_gneq = (char *)&ref_conf_data->gneq;
+ /* transfer 24 bit neq_map to mask */
+ mask = cuir->neq_map[2];
+ mask |= cuir->neq_map[1] << 8;
+ mask |= cuir->neq_map[0] << 16;
+
+ for (path = 0x80; path; path >>= 1) {
+ /* initialise data per path */
+ bitmask = mask;
+ pos = pathmask_to_pos(path);
+ conf_data = private->path_conf_data[pos];
+ pos = 8 - ffs(cuir->ned_map);
+ ned = (char *) &conf_data->neds[pos];
+ /* compare reference ned and per path ned */
+ if (memcmp(ref_ned, ned, sizeof(*ned)) != 0)
+ continue;
+ gneq = (char *)&conf_data->gneq;
+ /* compare reference gneq and per_path gneq under
+ 24 bit mask where mask bit 0 equals byte 7 of
+ the gneq and mask bit 24 equals byte 31 */
+ while (bitmask) {
+ pos = ffs(bitmask) - 1;
+ if (memcmp(&ref_gneq[31 - pos], &gneq[31 - pos], 1)
+ != 0)
+ break;
+ clear_bit(pos, &bitmask);
+ }
+ if (bitmask)
+ continue;
+ /* device and path match the reference values
+ add path to CUIR scope */
+ tbcpm |= path;
+ }
+ return tbcpm;
+}
+
+static void dasd_eckd_cuir_notify_user(struct dasd_device *device,
+ unsigned long paths,
+ struct subchannel_id sch_id, int action)
+{
+ struct channel_path_desc *desc;
+ int pos;
+
+ while (paths) {
+ /* get position of bit in mask */
+ pos = ffs(paths) - 1;
+ /* get channel path descriptor from this position */
+ desc = ccw_device_get_chp_desc(device->cdev, 7 - pos);
+ if (action == CUIR_QUIESCE)
+ pr_warn("Service on the storage server caused path "
+ "%x.%02x to go offline", sch_id.cssid,
+ desc ? desc->chpid : 0);
+ else if (action == CUIR_RESUME)
+ pr_info("Path %x.%02x is back online after service "
+ "on the storage server", sch_id.cssid,
+ desc ? desc->chpid : 0);
+ kfree(desc);
+ clear_bit(pos, &paths);
+ }
+}
+
+static int dasd_eckd_cuir_remove_path(struct dasd_device *device, __u8 lpum,
+ struct dasd_cuir_message *cuir)
+{
+ unsigned long tbcpm;
+
+ tbcpm = dasd_eckd_cuir_scope(device, lpum, cuir);
+ /* nothing to do if path is not in use */
+ if (!(device->path_data.opm & tbcpm))
+ return 0;
+ if (!(device->path_data.opm & ~tbcpm)) {
+ /* no path would be left if the CUIR action is taken
+ return error */
+ return -EINVAL;
+ }
+ /* remove device from operational path mask */
+ device->path_data.opm &= ~tbcpm;
+ device->path_data.cuirpm |= tbcpm;
+ return tbcpm;
+}
+
+/*
+ * walk through all devices and build a path mask to quiesce them
+ * return an error if the last path to a device would be removed