[SCSI] lpfc 8.2.3 : FC Discovery Fixes

FC Discovery Fixes:
- Fix up lpfc_drop_node() vs lpfc_nlp_not_used() usage
- Clear ADISC flag when unregistering RPI and REMOVE ndlps if in recovery.
- Fix usage of UNUSED list and ndlps
- Fix PLOGI race conditions
- Reset link if NameServer PLOGI errors occur
- Synchronize GID_FT queries with PLOGI receptions

Signed-off-by: James Smart <James.Smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 45 insertions, 51 deletions

diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index e181a98caf16..f64ce88e8a06 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -157,6 +157,8 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
         struct lpfc_vport *vport;
         struct lpfc_hba   *phba;
         uint8_t *name;
+        int  put_node;
+        int  put_rport;
         int warn_on = 0;
 
         rport = ndlp->rport;
@@ -178,9 +180,6 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
                 return;
 
         if (ndlp->nlp_type & NLP_FABRIC) {
-                int  put_node;
-                int  put_rport;
-
                 /* We will clean up these Nodes in linkup */
                 put_node = rdata->pnode != NULL;
                 put_rport = ndlp->rport != NULL;
@@ -222,23 +221,20 @@ lpfc_dev_loss_tmo_handler(struct lpfc_nodelist *ndlp)
                                  ndlp->nlp_state, ndlp->nlp_rpi);
         }
 
+        put_node = rdata->pnode != NULL;
+        put_rport = ndlp->rport != NULL;
+        rdata->pnode = NULL;
+        ndlp->rport = NULL;
+        if (put_node)
+                lpfc_nlp_put(ndlp);
+        if (put_rport)
+                put_device(&rport->dev);
+
         if (!(vport->load_flag & FC_UNLOADING) &&
             !(ndlp->nlp_flag & NLP_DELAY_TMO) &&
             !(ndlp->nlp_flag & NLP_NPR_2B_DISC) &&
-            (ndlp->nlp_state != NLP_STE_UNMAPPED_NODE))
+            (ndlp->nlp_state != NLP_STE_UNMAPPED_NODE)) {
                 lpfc_disc_state_machine(vport, ndlp, NULL, NLP_EVT_DEVICE_RM);
-        else {
-                int  put_node;
-                int  put_rport;
-
-                put_node = rdata->pnode != NULL;
-                put_rport = ndlp->rport != NULL;
-                rdata->pnode = NULL;
-                ndlp->rport = NULL;
-                if (put_node)
-                        lpfc_nlp_put(ndlp);
-                if (put_rport)
-                        put_device(&rport->dev);
         }
 }
 
@@ -546,11 +542,9 @@ lpfc_cleanup_rpis(struct lpfc_vport *vport, int remove)
         }
 }
 
-static void
+void
 lpfc_port_link_failure(struct lpfc_vport *vport)
 {
-        struct lpfc_nodelist *ndlp, *next_ndlp;
-
         /* Cleanup any outstanding RSCN activity */
         lpfc_els_flush_rscn(vport);
 
@@ -559,11 +553,6 @@ lpfc_port_link_failure(struct lpfc_vport *vport)
 
         lpfc_cleanup_rpis(vport, 0);
 
-        /* free any ndlp's on unused list */
-        list_for_each_entry_safe(ndlp, next_ndlp, &vport->fc_nodes, nlp_listp)
-                if (ndlp->nlp_state == NLP_STE_UNUSED_NODE)
-                        lpfc_drop_node(vport, ndlp);
-
         /* Turn off discovery timer if its running */
         lpfc_can_disctmo(vport);
 }
@@ -670,7 +659,6 @@ static void
 lpfc_linkup_port(struct lpfc_vport *vport)
 {
         struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
-        struct lpfc_nodelist *ndlp, *next_ndlp;
         struct lpfc_hba  *phba = vport->phba;
 
         if ((vport->load_flag & FC_UNLOADING) != 0)
@@ -697,11 +685,6 @@ lpfc_linkup_port(struct lpfc_vport *vport)
         if (vport->fc_flag & FC_LBIT)
                 lpfc_linkup_cleanup_nodes(vport);
 
-                                /* free any ndlp's in unused state */
-        list_for_each_entry_safe(ndlp, next_ndlp, &vport->fc_nodes,
-                                 nlp_listp)
-                if (ndlp->nlp_state == NLP_STE_UNUSED_NODE)
-                        lpfc_drop_node(vport, ndlp);
 }
 
 static int
@@ -1345,7 +1328,9 @@ out:
                 lpfc_mbuf_free(phba, mp->virt, mp->phys);
                 kfree(mp);
                 mempool_free(pmb, phba->mbox_mem_pool);
-                lpfc_drop_node(vport, ndlp);
+
+                /* If no other thread is using the ndlp, free it */
+                lpfc_nlp_not_used(ndlp);
 
                 if (phba->fc_topology == TOPOLOGY_LOOP) {
                         /*
@@ -1605,16 +1590,6 @@ lpfc_nlp_set_state(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                 ndlp->nlp_type &= ~NLP_FC_NODE;
         }
 
-        if ((old_state == NLP_STE_UNUSED_NODE) &&
-            (state != NLP_STE_UNUSED_NODE) &&
-            (ndlp->nlp_flag & NLP_DELAYED_RM)) {
-                /* We are using the ndlp after all, so reverse
-                 * the delayed removal of it.
-                 */
-                ndlp->nlp_flag &= ~NLP_DELAYED_RM;
-                lpfc_nlp_get(ndlp);
-        }
-
         if (list_empty(&ndlp->nlp_listp)) {
                 spin_lock_irq(shost->host_lock);
                 list_add_tail(&ndlp->nlp_listp, &vport->fc_nodes);
@@ -1646,9 +1621,16 @@ lpfc_dequeue_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 void
 lpfc_drop_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 {
+        /*
+         * Use of lpfc_drop_node and UNUSED list. lpfc_drop_node should
+         * be used if we wish to issue the "last" lpfc_nlp_put() to remove
+         * the ndlp from the vport.  The ndlp resides on the UNUSED list
+         * until ALL other outstanding threads have completed. Thus, if a
+         * ndlp is on the UNUSED list already, we should never do another
+         * lpfc_drop_node() on it.
+         */
         lpfc_nlp_set_state(vport, ndlp, NLP_STE_UNUSED_NODE);
-        if (!(ndlp->nlp_flag & NLP_DELAYED_RM))
-                lpfc_nlp_put(ndlp);
+        lpfc_nlp_put(ndlp);
         return;
 }
 
@@ -2116,6 +2098,12 @@ lpfc_setup_disc_node(struct lpfc_vport *vport, uint32_t did)
         }
         if (vport->fc_flag & FC_RSCN_MODE) {
                 if (lpfc_rscn_payload_check(vport, did)) {
+                        /* If we've already recieved a PLOGI from this NPort
+                         * we don't need to try to discover it again.
+                         */
+                        if (ndlp->nlp_flag & NLP_RCV_PLOGI)
+                                return NULL;
+
                         spin_lock_irq(shost->host_lock);
                         ndlp->nlp_flag |= NLP_NPR_2B_DISC;
                         spin_unlock_irq(shost->host_lock);
@@ -2128,8 +2116,13 @@ lpfc_setup_disc_node(struct lpfc_vport *vport, uint32_t did)
                 } else
                         ndlp = NULL;
         } else {
+                /* If we've already recieved a PLOGI from this NPort,
+                 * or we are already in the process of discovery on it,
+                 * we don't need to try to discover it again.
+                 */
                 if (ndlp->nlp_state == NLP_STE_ADISC_ISSUE ||
-                    ndlp->nlp_state == NLP_STE_PLOGI_ISSUE)
+                    ndlp->nlp_state == NLP_STE_PLOGI_ISSUE ||
+                    ndlp->nlp_flag & NLP_RCV_PLOGI)
                         return NULL;
                 lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
                 spin_lock_irq(shost->host_lock);
@@ -2497,6 +2490,7 @@ lpfc_disc_timeout_handler(struct lpfc_vport *vport)
                         if (ndlp->nlp_type & NLP_FABRIC) {
                                 /* Clean up the ndlp on Fabric connections */
                                 lpfc_drop_node(vport, ndlp);
+
                         } else if (!(ndlp->nlp_flag & NLP_NPR_ADISC)) {
                                 /* Fail outstanding IO now since device
                                  * is marked for PLOGI.
@@ -2515,7 +2509,7 @@ lpfc_disc_timeout_handler(struct lpfc_vport *vport)
                 /* Initial FLOGI timeout */
                 lpfc_printf_vlog(vport, KERN_ERR, LOG_DISCOVERY,
                                  "0222 Initial %s timeout\n",
-                                 vport->vpi ? "FLOGI" : "FDISC");
+                                 vport->vpi ? "FDISC" : "FLOGI");
 
                 /* Assume no Fabric and go on with discovery.
                  * Check for outstanding ELS FLOGI to abort.
@@ -2537,10 +2531,10 @@ lpfc_disc_timeout_handler(struct lpfc_vport *vport)
                 /* Next look for NameServer ndlp */
                 ndlp = lpfc_findnode_did(vport, NameServer_DID);
                 if (ndlp)
-                        lpfc_nlp_put(ndlp);
-                /* Start discovery */
-                lpfc_disc_start(vport);
-                break;
+                        lpfc_els_abort(phba, ndlp);
+
+                /* ReStart discovery */
+                goto restart_disc;
 
         case LPFC_NS_QRY:
         /* Check for wait for NameServer Rsp timeout */
@@ -2559,6 +2553,7 @@ lpfc_disc_timeout_handler(struct lpfc_vport *vport)
                 }
                 vport->fc_ns_retry = 0;
 
+restart_disc:
                 /*
                  * Discovery is over.
                  * set port_state to PORT_READY if SLI2.
@@ -2731,8 +2726,7 @@ __lpfc_find_node(struct lpfc_vport *vport, node_filter filter, void *param)
         struct lpfc_nodelist *ndlp;
 
         list_for_each_entry(ndlp, &vport->fc_nodes, nlp_listp) {
-                if (ndlp->nlp_state != NLP_STE_UNUSED_NODE &&
-                    filter(ndlp, param))
+                if (filter(ndlp, param))
                         return ndlp;
         }
         return NULL;