scsi: qedf: Honor status qualifier in FCP_RSP per spec

Handle scope and qualifier on SAM_STAT_TASK_SET_FULL or SAM_STAT_BUSY

[mkp: added braces to fix sparse complaint]

Link: https://lore.kernel.org/r/20200416084314.18851-5-skashyap@marvell.com
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qedf/qedf_io.c

@@ -1138,6 +1138,8 @@ void qedf_scsi_completion(struct qedf_ctx *qedf, struct fcoe_cqe *cqe,
 	int refcount;
 	u16 scope, qualifier = 0;
 	u8 fw_residual_flag = 0;
+	unsigned long flags = 0;
+	u16 chk_scope = 0;
 
 	if (!io_req)
 		return;
@@ -1271,16 +1273,8 @@ void qedf_scsi_completion(struct qedf_ctx *qedf, struct fcoe_cqe *cqe,
 				/* Lower 14 bits */
 				qualifier = fcp_rsp->retry_delay_timer & 0x3FFF;
 
-				if (qedf_retry_delay &&
-				    scope > 0 && qualifier > 0 &&
-				    qualifier <= 0x3FEF) {
-					/* Check we don't go over the max */
-					if (qualifier > QEDF_RETRY_DELAY_MAX)
-						qualifier =
-						    QEDF_RETRY_DELAY_MAX;
-					fcport->retry_delay_timestamp =
-					    jiffies + (qualifier * HZ / 10);
-				}
+				if (qedf_retry_delay)
+					chk_scope = 1;
 				/* Record stats */
 				if (io_req->cdb_status ==
 				    SAM_STAT_TASK_SET_FULL)
@@ -1291,6 +1285,36 @@ void qedf_scsi_completion(struct qedf_ctx *qedf, struct fcoe_cqe *cqe,
 		}
 		if (io_req->fcp_resid)
 			scsi_set_resid(sc_cmd, io_req->fcp_resid);
+
+		if (chk_scope == 1) {
+			if ((scope == 1 || scope == 2) &&
+			    (qualifier > 0 && qualifier <= 0x3FEF)) {
+				/* Check we don't go over the max */
+				if (qualifier > QEDF_RETRY_DELAY_MAX) {
+					qualifier = QEDF_RETRY_DELAY_MAX;
+					QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_IO,
+						  "qualifier = %d\n",
+						  (fcp_rsp->retry_delay_timer &
+						  0x3FFF));
+				}
+				QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_IO,
+					  "Scope = %d and qualifier = %d",
+					  scope, qualifier);
+				/*  Take fcport->rport_lock to
+				 *  update the retry_delay_timestamp
+				 */
+				spin_lock_irqsave(&fcport->rport_lock, flags);
+				fcport->retry_delay_timestamp =
+					jiffies + (qualifier * HZ / 10);
+				spin_unlock_irqrestore(&fcport->rport_lock,
+						       flags);
+
+			} else {
+				QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_IO,
+					  "combination of scope = %d and qualifier = %d is not handled in qedf.\n",
+					  scope, qualifier);
+			}
+		}
 		break;
 	default:
 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_IO, "fcp_status=%d.\n",