[SCSI] mpt2sas: Add support in the driver to check for valid response info

Add support in the driver to check for valid response info in the scsi
state, then check to see if the response code is
MPI2_SCSITASKMGMT_RSP_INVALID_FRAME; when this condition occurrs, the driver
will return DID_SOFT_ERROR.  A return code of DID_SOFT_ERROR will result in
a retry at the scsi-mid layer level.  An additional change added to obtain
the response code from the 1st byte of the response info instead of last.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: Eric Moore <Eric.moore@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/mpt2sas/mpt2sas_scsih.c

@@ -3111,7 +3111,7 @@ _scsih_scsi_ioc_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
 	if (scsi_state & MPI2_SCSI_STATE_RESPONSE_INFO_VALID) {
 		response_info = le32_to_cpu(mpi_reply->ResponseInfo);
 		response_bytes = (u8 *)&response_info;
-		_scsih_response_code(ioc, response_bytes[3]);
+		_scsih_response_code(ioc, response_bytes[0]);
 	}
 }
 #endif
@@ -3229,7 +3229,7 @@ _scsih_io_done(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply)
 	u8 scsi_status;
 	u32 log_info;
 	struct MPT2SAS_DEVICE *sas_device_priv_data;
-	u32 response_code;
+	u32 response_code = 0;
 
 	mpi_reply = mpt2sas_base_get_reply_virt_addr(ioc, reply);
 	scmd = _scsih_scsi_lookup_get(ioc, smid);
@@ -3251,17 +3251,17 @@ _scsih_io_done(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply)
 	}
 
 	/* turning off TLR */
+	scsi_state = mpi_reply->SCSIState;
+	if (scsi_state & MPI2_SCSI_STATE_RESPONSE_INFO_VALID)
+		response_code =
+		    le32_to_cpu(mpi_reply->ResponseInfo) & 0xFF;
 	if (!sas_device_priv_data->tlr_snoop_check) {
 		sas_device_priv_data->tlr_snoop_check++;
-		if (sas_device_priv_data->flags & MPT_DEVICE_TLR_ON) {
-			response_code = (le32_to_cpu(mpi_reply->ResponseInfo)
-			    >> 24);
-			if (response_code ==
-			    MPI2_SCSITASKMGMT_RSP_INVALID_FRAME)
+		if ((sas_device_priv_data->flags & MPT_DEVICE_TLR_ON) &&
+		    response_code == MPI2_SCSITASKMGMT_RSP_INVALID_FRAME)
 			sas_device_priv_data->flags &=
 			    ~MPT_DEVICE_TLR_ON;
 	}
-	}
 
 	xfer_cnt = le32_to_cpu(mpi_reply->TransferCount);
 	scsi_set_resid(scmd, scsi_bufflen(scmd) - xfer_cnt);
@@ -3271,7 +3271,6 @@ _scsih_io_done(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply)
 	else
 		log_info = 0;
 	ioc_status &= MPI2_IOCSTATUS_MASK;
-	scsi_state = mpi_reply->SCSIState;
 	scsi_status = mpi_reply->SCSIStatus;
 
 	if (ioc_status == MPI2_IOCSTATUS_SCSI_DATA_UNDERRUN && xfer_cnt == 0 &&
@@ -3356,8 +3355,10 @@ _scsih_io_done(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply)
 	case MPI2_IOCSTATUS_SCSI_RECOVERED_ERROR:
 	case MPI2_IOCSTATUS_SUCCESS:
 		scmd->result = (DID_OK << 16) | scsi_status;
-		if (scsi_state & (MPI2_SCSI_STATE_AUTOSENSE_FAILED |
-		     MPI2_SCSI_STATE_NO_SCSI_STATUS))
+		if (response_code ==
+		    MPI2_SCSITASKMGMT_RSP_INVALID_FRAME ||
+		    (scsi_state & (MPI2_SCSI_STATE_AUTOSENSE_FAILED |
+		     MPI2_SCSI_STATE_NO_SCSI_STATUS)))
 			scmd->result = DID_SOFT_ERROR << 16;
 		else if (scsi_state & MPI2_SCSI_STATE_TERMINATED)
 			scmd->result = DID_RESET << 16;