[SCSI] lpfc 8.1.2: Add module parameter to limit number of outstandin…

…g commands per lpfc HBA

Add module parameter to limit number of outstanding commands per lpfc HBA

Signed-off-by: Jamie Wellnitz <Jamie.Wellnitz@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/lpfc/lpfc_attr.c

@@ -519,6 +519,16 @@ LPFC_ATTR_HEX_RW(log_verbose, 0x0, 0x0, 0xffff, "Verbose logging bit-mask");
 LPFC_ATTR_R(lun_queue_depth, 30, 1, 128,
 	    "Max number of FCP commands we can queue to a specific LUN");
 
+/*
+# hba_queue_depth:  This parameter is used to limit the number of outstanding
+# commands per lpfc HBA. Value range is [32,8192]. If this parameter
+# value is greater than the maximum number of exchanges supported by the HBA,
+# then maximum number of exchanges supported by the HBA is used to determine
+# the hba_queue_depth.
+*/
+LPFC_ATTR_R(hba_queue_depth, 8192, 32, 8192,
+	    "Max number of FCP commands we can queue to a lpfc HBA");
+
 /*
 # Some disk devices have a "select ID" or "select Target" capability.
 # From a protocol standpoint "select ID" usually means select the
@@ -649,6 +659,7 @@ struct class_device_attribute *lpfc_host_attrs[] = {
 	&class_device_attr_lpfc_drvr_version,
 	&class_device_attr_lpfc_log_verbose,
 	&class_device_attr_lpfc_lun_queue_depth,
+	&class_device_attr_lpfc_hba_queue_depth,
 	&class_device_attr_lpfc_nodev_tmo,
 	&class_device_attr_lpfc_fcp_class,
 	&class_device_attr_lpfc_use_adisc,
@@ -1411,5 +1422,9 @@ lpfc_get_cfgparam(struct lpfc_hba *phba)
 	default:
 		phba->cfg_hba_queue_depth = LPFC_DFT_HBA_Q_DEPTH;
 	}
+
+	if (phba->cfg_hba_queue_depth > lpfc_hba_queue_depth)
+		lpfc_hba_queue_depth_init(phba, lpfc_hba_queue_depth);
+
 	return;
 }