+ unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq));
+
+ if (blk_rq_sectors(rq) > max_sectors) {
+ /*
+ * SCSI device does not have a good way to return if
+ * Write Same/Zero is actually supported. If a device rejects
+ * a non-read/write command (discard, write same,etc.) the
+ * low-level device driver will set the relevant queue limit to
+ * 0 to prevent blk-lib from issuing more of the offending
+ * operations. Commands queued prior to the queue limit being
+ * reset need to be completed with BLK_STS_NOTSUPP to avoid I/O
+ * errors being propagated to upper layers.
+ */
+ if (max_sectors == 0)
+ return BLK_STS_NOTSUPP;
+