scsi: lpfc: Remove ndlp when a PLOGI/ADISC/PRLI/REG_RPI ultimately fails

When a PLOGI/ADISC/PRLI/REG_RPI fails, the node remains in the nodelist in
that state.  Although the driver now frees a node when the ref count goes
to zero, in this case the ref cnt doesn't reach zero because there isn't a
mechanism to release the final reference.  Discovery just stops.

Fix by calling the node discovery state machine DEVICE_RM event whenever
one of these commands fail. This will remove the final reference count and
trigger node release.

Link: https://lore.kernel.org/r/20201115192646.12977-7-james.smart@broadcom.com
Co-developed-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

2 files changed, 85 insertions, 20 deletions

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 020300b97bd3..388728fbcc26 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -1988,12 +1988,25 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 				 "2753 PLOGI failure DID:%06X Status:x%x/x%x\n",
 				 ndlp->nlp_DID, irsp->ulpStatus,
 				 irsp->un.ulpWord[4]);
-		/* Do not call DSM for lpfc_els_abort'ed ELS cmds. Just execute
-		 * the final node put to free it to the pool.
+
+		/* Do not call DSM for lpfc_els_abort'ed ELS cmds */
+		if (lpfc_error_lost_link(irsp))
+			goto check_plogi;
+		else
+			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
+						NLP_EVT_CMPL_PLOGI);
+
+		/* As long as this node is not registered with the scsi or nvme
+		 * transport, it is no longer an active node.  Otherwise
+		 * devloss handles the final cleanup.
 		 */
-		if (!lpfc_error_lost_link(irsp))
+		if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) {
+			spin_lock_irq(&ndlp->lock);
+			ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+			spin_unlock_irq(&ndlp->lock);
 			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
 						NLP_EVT_DEVICE_RM);
+		}
 	} else {
 		/* Good status, call state machine */
 		prsp = list_entry(((struct lpfc_dmabuf *)
@@ -2004,6 +2017,7 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 					NLP_EVT_CMPL_PLOGI);
 	}
 
+ check_plogi:
 	if (disc && vport->num_disc_nodes) {
 		/* Check to see if there are more PLOGIs to be sent */
 		lpfc_more_plogi(vport);
@@ -2243,6 +2257,20 @@ lpfc_cmpl_els_prli(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 		else
 			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
 						NLP_EVT_CMPL_PRLI);
+
+		/* As long as this node is not registered with the SCSI
+		 * or NVMe transport and no other PRLIs are outstanding,
+		 * it is no longer an active node.  Otherwise devloss
+		 * handles the final cleanup.
+		 */
+		if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD)) &&
+		    !ndlp->fc4_prli_sent) {
+			spin_lock_irq(&ndlp->lock);
+			ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+			spin_unlock_irq(&ndlp->lock);
+			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
+						NLP_EVT_DEVICE_RM);
+		}
 	} else {
 		/* Good status, call state machine.  However, if another
 		 * PRLI is outstanding, don't call the state machine
@@ -2655,14 +2683,29 @@ lpfc_cmpl_els_adisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 				 ndlp->nlp_DID, irsp->ulpStatus,
 				 irsp->un.ulpWord[4]);
 		/* Do not call DSM for lpfc_els_abort'ed ELS cmds */
-		if (!lpfc_error_lost_link(irsp))
+		if (lpfc_error_lost_link(irsp))
+			goto check_adisc;
+		else
 			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
 						NLP_EVT_CMPL_ADISC);
+
+		/* As long as this node is not registered with the SCSI or NVMe
+		 * transport, it is no longer an active node. Otherwise
+		 * devloss handles the final cleanup.
+		 */
+		if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) {
+			spin_lock_irq(&ndlp->lock);
+			ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+			spin_unlock_irq(&ndlp->lock);
+			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
+						NLP_EVT_DEVICE_RM);
+		}
 	} else
 		/* Good status, call state machine */
 		lpfc_disc_state_machine(vport, ndlp, cmdiocb,
 					NLP_EVT_CMPL_ADISC);
 
+ check_adisc:
 	/* Check to see if there are more ADISCs to be sent */
 	if (disc && vport->num_disc_nodes)
 		lpfc_more_adisc(vport);
@@ -2879,8 +2922,21 @@ out:
 				 irsp->un.ulpWord[4], irsp->ulpTimeout,
 				 vport->num_disc_nodes);
 		lpfc_disc_start(vport);
+		return;
+	}
+
+	/* Cleanup path for failed REG_RPI handling. If REG_RPI fails, the
+	 * driver sends a LOGO to the rport to cleanup.  For fabric and
+	 * initiator ports cleanup the node as long as it the node is not
+	 * register with the transport.
+	 */
+	if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) {
+		spin_lock_irq(&ndlp->lock);
+		ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+		spin_unlock_irq(&ndlp->lock);
+		lpfc_disc_state_machine(vport, ndlp, cmdiocb,
+					NLP_EVT_DEVICE_RM);
 	}
-	return;
 }
 
 /**
diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 8c99e89c7685..c6d7620b49a3 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -204,10 +204,13 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
 
 	spin_lock_irqsave(&ndlp->lock, iflags);
 	ndlp->nlp_flag |= NLP_IN_DEV_LOSS;
+	ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+
 	/*
-	 * The backend does not expect any more calls assoicated with this
-	 * rport, Remove the association between rport and ndlp
+	 * The backend does not expect any more calls associated with this
+	 * rport. Remove the association between rport and ndlp.
 	 */
+	ndlp->fc4_xpt_flags &= ~SCSI_XPT_REGD;
 	((struct lpfc_rport_data *)rport->dd_data)->pnode = NULL;
 	ndlp->rport = NULL;
 	spin_unlock_irqrestore(&ndlp->lock, iflags);
@@ -248,7 +251,6 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
 	int warn_on = 0;
 	int fcf_inuse = 0;
 	unsigned long iflags;
-	u32 fc4_xpt_flags;
 
 	vport = ndlp->vport;
 	shost = lpfc_shost_from_vport(vport);
@@ -267,10 +269,11 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
 			      ndlp->nlp_DID, ndlp->nlp_type, ndlp->nlp_sid);
 
 	lpfc_printf_vlog(ndlp->vport, KERN_INFO, LOG_NODE,
-			 "3182 %s x%06x, nflag x%x xflags x%x\n",
+			 "3182 %s x%06x, nflag x%x xflags x%x refcnt %d\n",
 			 __func__, ndlp->nlp_DID, ndlp->nlp_flag,
-			 ndlp->fc4_xpt_flags);
+			 ndlp->fc4_xpt_flags, kref_read(&ndlp->kref));
 
+	/* If the driver is recovering the rport, ignore devloss. */
 	if (ndlp->nlp_state == NLP_STE_MAPPED_NODE) {
 		lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
 				 "0284 Devloss timeout Ignored on "
@@ -282,8 +285,11 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
 		return fcf_inuse;
 	}
 
-	if (ndlp->nlp_type & NLP_FABRIC)
+	/* Fabric nodes are done. */
+	if (ndlp->nlp_type & NLP_FABRIC) {
+		lpfc_nlp_put(ndlp);
 		return fcf_inuse;
+	}
 
 	if (ndlp->nlp_sid != NLP_NO_SID) {
 		warn_on = 1;
@@ -311,12 +317,7 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
 				 ndlp->nlp_state, ndlp->nlp_rpi);
 	}
 
-	/* Should be final reference removal triggering a node free. */
-	spin_lock_irqsave(shost->host_lock, iflags);
-	fc4_xpt_flags = ndlp->fc4_xpt_flags;
-	spin_unlock_irqrestore(shost->host_lock, iflags);
-
-	if (!(fc4_xpt_flags & (NVME_XPT_REGD | SCSI_XPT_REGD)))
+	if (!(ndlp->fc4_xpt_flags & NVME_XPT_REGD))
 		lpfc_disc_state_machine(vport, ndlp, NULL, NLP_EVT_DEVICE_RM);
 
 	return fcf_inuse;
@@ -3587,7 +3588,7 @@ lpfc_mbx_cmpl_reg_login(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 	pmb->ctx_buf = NULL;
 	pmb->ctx_ndlp = NULL;
 
-	lpfc_printf_vlog(vport, KERN_INFO, LOG_SLI,
+	lpfc_printf_vlog(vport, KERN_INFO, LOG_SLI | LOG_NODE | LOG_DISCOVERY,
 			 "0002 rpi:%x DID:%x flg:%x %d x%px\n",
 			 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
 			 kref_read(&ndlp->kref),
@@ -4079,8 +4080,16 @@ out:
 		kfree(mp);
 		mempool_free(pmb, phba->mbox_mem_pool);
 
-		/* If no other thread is using the ndlp, free it */
-		lpfc_nlp_not_used(ndlp);
+		/* If the node is not registered with the scsi or nvme
+		 * transport, remove the fabric node.  The failed reg_login
+		 * is terminal.
+		 */
+		if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) {
+			spin_lock_irq(&ndlp->lock);
+			ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
+			spin_unlock_irq(&ndlp->lock);
+			lpfc_nlp_not_used(ndlp);
+		}
 
 		if (phba->fc_topology == LPFC_TOPOLOGY_LOOP) {
 			/*