- do {
- if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
- return -ENOMEM;
- rc = idr_get_new(&ext_devt_idr, part, &idx);
- } while (rc == -EAGAIN);
-
- if (rc)
- return rc;
-
- if (idx > MAX_EXT_DEVT) {
- idr_remove(&ext_devt_idr, idx);
- return -EBUSY;
- }
+ mutex_lock(&ext_devt_mutex);
+ idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_KERNEL);
+ mutex_unlock(&ext_devt_mutex);
+ if (idx < 0)
+ return idx == -ENOSPC ? -EBUSY : idx;