scsi: lpfc: Implement GID_PT on Nameserver query to support faster failover

The switches seem to respond faster to GID_PT vs GID_FT NameServer
queries.  Add support for GID_PT to be used over GID_FT to enable
faster storage failover detection. Includes addition of new module
parameter to select between GID_PT and GID_FT (GID_FT is default).

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 206 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/lpfc_ct.c b/drivers/scsi/lpfc/lpfc_ct.c
index 789ad1502534..62e8ae3b4685 100644
--- a/drivers/scsi/lpfc/lpfc_ct.c
+++ b/drivers/scsi/lpfc/lpfc_ct.c
@@ -832,6 +832,198 @@ out:
 }
 
 static void
+lpfc_cmpl_ct_cmd_gid_pt(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
+			struct lpfc_iocbq *rspiocb)
+{
+	struct lpfc_vport *vport = cmdiocb->vport;
+	struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
+	IOCB_t *irsp;
+	struct lpfc_dmabuf *outp;
+	struct lpfc_dmabuf *inp;
+	struct lpfc_sli_ct_request *CTrsp;
+	struct lpfc_sli_ct_request *CTreq;
+	struct lpfc_nodelist *ndlp;
+	int rc;
+
+	/* First save ndlp, before we overwrite it */
+	ndlp = cmdiocb->context_un.ndlp;
+
+	/* we pass cmdiocb to state machine which needs rspiocb as well */
+	cmdiocb->context_un.rsp_iocb = rspiocb;
+	inp = (struct lpfc_dmabuf *)cmdiocb->context1;
+	outp = (struct lpfc_dmabuf *)cmdiocb->context2;
+	irsp = &rspiocb->iocb;
+
+	lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_CT,
+			      "GID_PT cmpl:     status:x%x/x%x rtry:%d",
+			      irsp->ulpStatus, irsp->un.ulpWord[4],
+			      vport->fc_ns_retry);
+
+	/* Don't bother processing response if vport is being torn down. */
+	if (vport->load_flag & FC_UNLOADING) {
+		if (vport->fc_flag & FC_RSCN_MODE)
+			lpfc_els_flush_rscn(vport);
+		goto out;
+	}
+
+	if (lpfc_els_chk_latt(vport)) {
+		lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
+				 "4108 Link event during NS query\n");
+		if (vport->fc_flag & FC_RSCN_MODE)
+			lpfc_els_flush_rscn(vport);
+		lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+		goto out;
+	}
+	if (lpfc_error_lost_link(irsp)) {
+		lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
+				 "4101 NS query failed due to link event\n");
+		if (vport->fc_flag & FC_RSCN_MODE)
+			lpfc_els_flush_rscn(vport);
+		goto out;
+	}
+
+	spin_lock_irq(shost->host_lock);
+	if (vport->fc_flag & FC_RSCN_DEFERRED) {
+		vport->fc_flag &= ~FC_RSCN_DEFERRED;
+		spin_unlock_irq(shost->host_lock);
+
+		/* This is a GID_PT completing so the gidft_inp counter was
+		 * incremented before the GID_PT was issued to the wire.
+		 */
+		vport->gidft_inp--;
+
+		/*
+		 * Skip processing the NS response
+		 * Re-issue the NS cmd
+		 */
+		lpfc_printf_vlog(vport, KERN_INFO, LOG_ELS,
+				 "4102 Process Deferred RSCN Data: x%x x%x\n",
+				 vport->fc_flag, vport->fc_rscn_id_cnt);
+		lpfc_els_handle_rscn(vport);
+
+		goto out;
+	}
+	spin_unlock_irq(shost->host_lock);
+
+	if (irsp->ulpStatus) {
+		/* Check for retry */
+		if (vport->fc_ns_retry < LPFC_MAX_NS_RETRY) {
+			if (irsp->ulpStatus != IOSTAT_LOCAL_REJECT ||
+			    (irsp->un.ulpWord[4] & IOERR_PARAM_MASK) !=
+			    IOERR_NO_RESOURCES)
+				vport->fc_ns_retry++;
+
+			/* CT command is being retried */
+			vport->gidft_inp--;
+			rc = lpfc_ns_cmd(vport, SLI_CTNS_GID_PT,
+					 vport->fc_ns_retry, GID_PT_N_PORT);
+			if (rc == 0)
+				goto out;
+		}
+		if (vport->fc_flag & FC_RSCN_MODE)
+			lpfc_els_flush_rscn(vport);
+		lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+		lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+				 "4103 GID_FT Query error: 0x%x 0x%x\n",
+				 irsp->ulpStatus, vport->fc_ns_retry);
+	} else {
+		/* Good status, continue checking */
+		CTreq = (struct lpfc_sli_ct_request *)inp->virt;
+		CTrsp = (struct lpfc_sli_ct_request *)outp->virt;
+		if (CTrsp->CommandResponse.bits.CmdRsp ==
+		    cpu_to_be16(SLI_CT_RESPONSE_FS_ACC)) {
+			lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
+					 "4105 NameServer Rsp Data: x%x x%x\n",
+					 vport->fc_flag,
+					 CTreq->un.gid.Fc4Type);
+
+			lpfc_ns_rsp(vport,
+				    outp,
+				    CTreq->un.gid.Fc4Type,
+				    (uint32_t)(irsp->un.genreq64.bdl.bdeSize));
+		} else if (CTrsp->CommandResponse.bits.CmdRsp ==
+			   be16_to_cpu(SLI_CT_RESPONSE_FS_RJT)) {
+			/* NameServer Rsp Error */
+			if ((CTrsp->ReasonCode == SLI_CT_UNABLE_TO_PERFORM_REQ)
+			    && (CTrsp->Explanation == SLI_CT_NO_FC4_TYPES)) {
+				lpfc_printf_vlog(
+					vport, KERN_INFO, LOG_DISCOVERY,
+					"4106 No NameServer Entries "
+					"Data: x%x x%x x%x x%x\n",
+					CTrsp->CommandResponse.bits.CmdRsp,
+					(uint32_t)CTrsp->ReasonCode,
+					(uint32_t)CTrsp->Explanation,
+					vport->fc_flag);
+
+				lpfc_debugfs_disc_trc(
+				vport, LPFC_DISC_TRC_CT,
+				"GID_PT no entry  cmd:x%x rsn:x%x exp:x%x",
+				(uint32_t)CTrsp->CommandResponse.bits.CmdRsp,
+				(uint32_t)CTrsp->ReasonCode,
+				(uint32_t)CTrsp->Explanation);
+			} else {
+				lpfc_printf_vlog(
+					vport, KERN_INFO, LOG_DISCOVERY,
+					"4107 NameServer Rsp Error "
+					"Data: x%x x%x x%x x%x\n",
+					CTrsp->CommandResponse.bits.CmdRsp,
+					(uint32_t)CTrsp->ReasonCode,
+					(uint32_t)CTrsp->Explanation,
+					vport->fc_flag);
+
+				lpfc_debugfs_disc_trc(
+				vport, LPFC_DISC_TRC_CT,
+				"GID_PT rsp err1  cmd:x%x rsn:x%x exp:x%x",
+				(uint32_t)CTrsp->CommandResponse.bits.CmdRsp,
+				(uint32_t)CTrsp->ReasonCode,
+				(uint32_t)CTrsp->Explanation);
+			}
+		} else {
+			/* NameServer Rsp Error */
+			lpfc_printf_vlog(vport, KERN_ERR, LOG_DISCOVERY,
+					 "4109 NameServer Rsp Error "
+					 "Data: x%x x%x x%x x%x\n",
+					 CTrsp->CommandResponse.bits.CmdRsp,
+					 (uint32_t)CTrsp->ReasonCode,
+					 (uint32_t)CTrsp->Explanation,
+					 vport->fc_flag);
+
+			lpfc_debugfs_disc_trc(
+				vport, LPFC_DISC_TRC_CT,
+				"GID_PT rsp err2  cmd:x%x rsn:x%x exp:x%x",
+				(uint32_t)CTrsp->CommandResponse.bits.CmdRsp,
+				(uint32_t)CTrsp->ReasonCode,
+				(uint32_t)CTrsp->Explanation);
+		}
+		vport->gidft_inp--;
+	}
+	/* Link up / RSCN discovery */
+	if ((vport->num_disc_nodes == 0) &&
+	    (vport->gidft_inp == 0)) {
+		/*
+		 * The driver has cycled through all Nports in the RSCN payload.
+		 * Complete the handling by cleaning up and marking the
+		 * current driver state.
+		 */
+		if (vport->port_state >= LPFC_DISC_AUTH) {
+			if (vport->fc_flag & FC_RSCN_MODE) {
+				lpfc_els_flush_rscn(vport);
+				spin_lock_irq(shost->host_lock);
+				vport->fc_flag |= FC_RSCN_MODE; /* RSCN still */
+				spin_unlock_irq(shost->host_lock);
+			} else {
+				lpfc_els_flush_rscn(vport);
+			}
+		}
+
+		lpfc_disc_start(vport);
+	}
+out:
+	cmdiocb->context_un.ndlp = ndlp; /* Now restore ndlp for free */
+	lpfc_ct_free_iocb(phba, cmdiocb);
+}
+
+static void
 lpfc_cmpl_ct_cmd_gff_id(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 			struct lpfc_iocbq *rspiocb)
 {
@@ -1365,6 +1557,8 @@ lpfc_ns_cmd(struct lpfc_vport *vport, int cmdcode,
 	bpl->tus.f.bdeFlags = 0;
 	if (cmdcode == SLI_CTNS_GID_FT)
 		bpl->tus.f.bdeSize = GID_REQUEST_SZ;
+	else if (cmdcode == SLI_CTNS_GID_PT)
+		bpl->tus.f.bdeSize = GID_REQUEST_SZ;
 	else if (cmdcode == SLI_CTNS_GFF_ID)
 		bpl->tus.f.bdeSize = GFF_REQUEST_SZ;
 	else if (cmdcode == SLI_CTNS_GFT_ID)
@@ -1405,6 +1599,18 @@ lpfc_ns_cmd(struct lpfc_vport *vport, int cmdcode,
 		rsp_size = FC_MAX_NS_RSP;
 		break;
 
+	case SLI_CTNS_GID_PT:
+		CtReq->CommandResponse.bits.CmdRsp =
+		    cpu_to_be16(SLI_CTNS_GID_PT);
+		CtReq->un.gid.PortType = context;
+
+		if (vport->port_state < LPFC_NS_QRY)
+			vport->port_state = LPFC_NS_QRY;
+		lpfc_set_disctmo(vport);
+		cmpl = lpfc_cmpl_ct_cmd_gid_pt;
+		rsp_size = FC_MAX_NS_RSP;
+		break;
+
 	case SLI_CTNS_GFF_ID:
 		CtReq->CommandResponse.bits.CmdRsp =
 			cpu_to_be16(SLI_CTNS_GFF_ID);