scsi: smartpqi: Reporting 'logical unit failure'

When the HARDWARE_ERROR/0x3e/0x1 case is triggered, the logical volume
is offlined.  When reading the kernel log, the reason why the device
got offlined isn't reported to the user.  This situation makes it
difficult for admins to root cause.

Log a message when this condition occurs.

[mkp: tweaked commit message]
Signed-off-by: Erwan Velu <e.velu@criteo.com>
Acked-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/smartpqi/smartpqi_init.c

@@ -2764,6 +2764,12 @@ static void pqi_process_raid_io_error(struct pqi_io_request *io_request)
 				sshdr.sense_key == HARDWARE_ERROR &&
 				sshdr.asc == 0x3e &&
 				sshdr.ascq == 0x1) {
+			struct pqi_ctrl_info *ctrl_info = shost_to_hba(scmd->device->host);
+			struct pqi_scsi_dev *device = scmd->device->hostdata;
+
+			if (printk_ratelimit())
+				scmd_printk(KERN_ERR, scmd, "received 'logical unit failure' from controller for scsi %d:%d:%d:%d\n",
+					ctrl_info->scsi_host->host_no, device->bus, device->target, device->lun);
 			pqi_take_device_offline(scmd->device, "RAID");
 			host_byte = DID_NO_CONNECT;
 		}