+
+out_error_dev:
+ hvc_remove(priv->hvc);
+out_error_hvc:
+ free_page((unsigned long) priv->sndbuf);
+ kfree(priv);
+
+ return rc;
+}
+
+/**
+ * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances
+ */
+static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv)
+{
+ hvc_remove(priv->hvc);
+ device_unregister(priv->dev);
+ free_page((unsigned long) priv->sndbuf);
+ kfree(priv);
+}
+
+/**
+ * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID
+ * @filter: String containing a comma-separated list of z/VM user IDs
+ */
+static const char *hvc_iucv_parse_filter(const char *filter, char *dest)
+{
+ const char *nextdelim, *residual;
+ size_t len;
+
+ nextdelim = strchr(filter, ',');
+ if (nextdelim) {
+ len = nextdelim - filter;
+ residual = nextdelim + 1;
+ } else {
+ len = strlen(filter);
+ residual = filter + len;
+ }
+
+ if (len == 0)
+ return ERR_PTR(-EINVAL);
+
+ /* check for '\n' (if called from sysfs) */
+ if (filter[len - 1] == '\n')
+ len--;
+
+ if (len > 8)
+ return ERR_PTR(-EINVAL);
+
+ /* pad with blanks and save upper case version of user ID */
+ memset(dest, ' ', 8);
+ while (len--)
+ dest[len] = toupper(filter[len]);
+ return residual;
+}
+
+/**
+ * hvc_iucv_setup_filter() - Set up z/VM user ID filter
+ * @filter: String consisting of a comma-separated list of z/VM user IDs
+ *
+ * The function parses the @filter string and creates an array containing
+ * the list of z/VM user ID filter entries.
+ * Return code 0 means success, -EINVAL if the filter is syntactically
+ * incorrect, -ENOMEM if there was not enough memory to allocate the
+ * filter list array, or -ENOSPC if too many z/VM user IDs have been specified.
+ */
+static int hvc_iucv_setup_filter(const char *val)
+{
+ const char *residual;
+ int err;
+ size_t size, count;
+ void *array, *old_filter;
+
+ count = strlen(val);
+ if (count == 0 || (count == 1 && val[0] == '\n')) {
+ size = 0;
+ array = NULL;
+ goto out_replace_filter; /* clear filter */
+ }
+
+ /* count user IDs in order to allocate sufficient memory */
+ size = 1;
+ residual = val;
+ while ((residual = strchr(residual, ',')) != NULL) {
+ residual++;
+ size++;
+ }
+
+ /* check if the specified list exceeds the filter limit */
+ if (size > MAX_VMID_FILTER)
+ return -ENOSPC;
+
+ array = kzalloc(size * 8, GFP_KERNEL);
+ if (!array)
+ return -ENOMEM;
+
+ count = size;
+ residual = val;
+ while (*residual && count) {
+ residual = hvc_iucv_parse_filter(residual,
+ array + ((size - count) * 8));
+ if (IS_ERR(residual)) {
+ err = PTR_ERR(residual);
+ kfree(array);
+ goto out_err;
+ }
+ count--;
+ }
+
+out_replace_filter:
+ write_lock_bh(&hvc_iucv_filter_lock);
+ old_filter = hvc_iucv_filter;
+ hvc_iucv_filter_size = size;
+ hvc_iucv_filter = array;
+ write_unlock_bh(&hvc_iucv_filter_lock);
+ kfree(old_filter);
+
+ err = 0;
+out_err:
+ return err;