From: Vijay Chauhan <vijay.chauhan@lsi.com>
Subject: Retry NOT READY for rdac device handler
References: bnc#496502

During device discovery read capacity fails with 0x020401 and sets the device
size to 0. As a reason any I/O submitted to this path gets killed at sd_prep_fn
with BLKPREP_KILL. This patch is to retry for 0x020401. NEED_RETRY in
scsi_decide_disposition does not give sufficient time for the device to become
ready. 

Signed-off-by: Vijay Chauhan <vijay.chauhan@lsi.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>

diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c
index 77b724f..4c97279 100644
--- a/drivers/scsi/device_handler/scsi_dh_rdac.c
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -548,6 +548,11 @@ static int rdac_check_sense(struct scsi_device *sdev,
 	struct rdac_dh_data *h = get_rdac_data(sdev);
 	switch (sense_hdr->sense_key) {
 	case NOT_READY:
+		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
+			/* LUN Not Ready - In process of becoming ready
+			 * Just retry.
+			 */
+			return ADD_TO_MLQUEUE;
 		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
 			/* LUN Not Ready - Storage firmware incompatible
 			 * Manual code synchonisation required.