scsi xcopy: suppress error messages

This patch suppresses error messages when copying between two arrays that
support XCOPY each, but that cannot copy data between each other.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

---
 drivers/scsi/sd.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

Index: linux-3.18-rc1/drivers/scsi/sd.c
===================================================================
--- linux-3.18-rc1.orig/drivers/scsi/sd.c	2014-10-21 00:48:51.000000000 +0200
+++ linux-3.18-rc1/drivers/scsi/sd.c	2014-10-21 00:49:21.000000000 +0200
@@ -1935,6 +1935,18 @@ static int sd_done(struct scsi_cmnd *SCp
 					req->cmd_flags |= REQ_QUIET;
 				}
 			}
+		} else if (sshdr.asc == 0x26) {
+			switch (op) {
+			/*
+			 * Copying between two arrays that support XCOPY, but
+			 * cannot access each other.
+			 */
+			case EXTENDED_COPY:
+				good_bytes = 0;
+				req->__data_len = blk_rq_bytes(req);
+				req->cmd_flags |= REQ_QUIET;
+				break;
+			}
 		}
 		break;
 	default: