[SCSI] lpfc 8.1.12 : Reference count node structures for node lifetime management

Reference count node structures for node lifetime management.

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

1 files changed, 72 insertions, 35 deletions

diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 164af8a7e95d..8ba2f4eadcdd 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -158,6 +158,8 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
         else {
                 rdata->pnode = NULL;
                 ndlp->rport = NULL;
+                lpfc_nlp_put(ndlp);
+                put_device(&rport->dev);
         }
 
         return;
@@ -960,6 +962,7 @@ lpfc_mbx_cmpl_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
         lpfc_mbuf_free(phba, mp->virt, mp->phys);
         kfree(mp);
         mempool_free( pmb, phba->mbox_mem_pool);
+        lpfc_nlp_put(ndlp);
 
         return;
 }
@@ -986,11 +989,14 @@ lpfc_mbx_cmpl_fabric_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
         ndlp = (struct lpfc_nodelist *) pmb->context2;
         mp = (struct lpfc_dmabuf *) (pmb->context1);
 
+        pmb->context1 = NULL;
+        pmb->context2 = NULL;
+
         if (mb->mbxStatus) {
                 lpfc_mbuf_free(phba, mp->virt, mp->phys);
                 kfree(mp);
-                mempool_free( pmb, phba->mbox_mem_pool);
-                mempool_free( ndlp, phba->nlp_mem_pool);
+                mempool_free(pmb, phba->mbox_mem_pool);
+                lpfc_nlp_put(ndlp);
 
                 /* FLOGI failed, so just use loop map to make discovery list */
                 lpfc_disc_list_loopmap(phba);
@@ -1000,12 +1006,12 @@ lpfc_mbx_cmpl_fabric_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
                 return;
         }
 
-        pmb->context1 = NULL;
-
         ndlp->nlp_rpi = mb->un.varWords[0];
         ndlp->nlp_type |= NLP_FABRIC;
         lpfc_nlp_set_state(phba, ndlp, NLP_STE_UNMAPPED_NODE);
 
+        lpfc_nlp_put(ndlp);     /* Drop the reference from the mbox */
+
         if (phba->hba_state == LPFC_FABRIC_CFG_LINK) {
                 /* This NPort has been assigned an NPort_ID by the fabric as a
                  * result of the completed fabric login.  Issue a State Change
@@ -1027,7 +1033,7 @@ lpfc_mbx_cmpl_fabric_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
                                 lpfc_disc_start(phba);
                                 lpfc_mbuf_free(phba, mp->virt, mp->phys);
                                 kfree(mp);
-                                mempool_free( pmb, phba->mbox_mem_pool);
+                                mempool_free(pmb, phba->mbox_mem_pool);
                                 return;
                         } else {
                                 lpfc_nlp_init(phba, ndlp, NameServer_DID);
@@ -1050,7 +1056,7 @@ lpfc_mbx_cmpl_fabric_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
 
         lpfc_mbuf_free(phba, mp->virt, mp->phys);
         kfree(mp);
-        mempool_free( pmb, phba->mbox_mem_pool);
+        mempool_free(pmb, phba->mbox_mem_pool);
         return;
 }
 
@@ -1075,6 +1081,7 @@ lpfc_mbx_cmpl_ns_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
         mp = (struct lpfc_dmabuf *) (pmb->context1);
 
         if (mb->mbxStatus) {
+                lpfc_nlp_put(ndlp);
                 lpfc_mbuf_free(phba, mp->virt, mp->phys);
                 kfree(mp);
                 mempool_free(pmb, phba->mbox_mem_pool);
@@ -1110,6 +1117,7 @@ lpfc_mbx_cmpl_ns_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
                 lpfc_disc_start(phba);
         }
 
+        lpfc_nlp_put(ndlp);
         lpfc_mbuf_free(phba, mp->virt, mp->phys);
         kfree(mp);
         mempool_free( pmb, phba->mbox_mem_pool);
@@ -1118,8 +1126,7 @@ lpfc_mbx_cmpl_ns_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
 }
 
 static void
-lpfc_register_remote_port(struct lpfc_hba * phba,
-                            struct lpfc_nodelist * ndlp)
+lpfc_register_remote_port(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
 {
         struct fc_rport *rport;
         struct lpfc_rport_data *rdata;
@@ -1131,8 +1138,19 @@ lpfc_register_remote_port(struct lpfc_hba * phba,
         rport_ids.port_id = ndlp->nlp_DID;
         rport_ids.roles = FC_RPORT_ROLE_UNKNOWN;
 
+        /*
+         * We leave our node pointer in rport->dd_data when we unregister a
+         * FCP target port.  But fc_remote_port_add zeros the space to which
+         * rport->dd_data points.  So, if we're reusing a previously
+         * registered port, drop the reference that we took the last time we
+         * registered the port.
+         */
+        if (ndlp->rport && ndlp->rport->dd_data &&
+            *(struct lpfc_rport_data **) ndlp->rport->dd_data) {
+                lpfc_nlp_put(ndlp);
+        }
         ndlp->rport = rport = fc_remote_port_add(phba->host, 0, &rport_ids);
-        if (!rport) {
+        if (!rport || !get_device(&rport->dev)) {
                 dev_printk(KERN_WARNING, &phba->pcidev->dev,
                            "Warning: fc_remote_port_add failed\n");
                 return;
@@ -1142,7 +1160,7 @@ lpfc_register_remote_port(struct lpfc_hba * phba,
         rport->maxframe_size = ndlp->nlp_maxframe;
         rport->supported_classes = ndlp->nlp_class_sup;
         rdata = rport->dd_data;
-        rdata->pnode = ndlp;
+        rdata->pnode = lpfc_nlp_get(ndlp);
 
         if (ndlp->nlp_type & NLP_FCP_TARGET)
                 rport_ids.roles |= FC_RPORT_ROLE_FCP_TARGET;
@@ -1162,8 +1180,7 @@ lpfc_register_remote_port(struct lpfc_hba * phba,
 }
 
 static void
-lpfc_unregister_remote_port(struct lpfc_hba * phba,
-                            struct lpfc_nodelist * ndlp)
+lpfc_unregister_remote_port(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
 {
         struct fc_rport *rport = ndlp->rport;
         struct lpfc_rport_data *rdata = rport->dd_data;
@@ -1171,6 +1188,8 @@ lpfc_unregister_remote_port(struct lpfc_hba * phba,
         if (rport->scsi_target_id == -1) {
                 ndlp->rport = NULL;
                 rdata->pnode = NULL;
+                lpfc_nlp_put(ndlp);
+                put_device(&rport->dev);
         }
 
         fc_remote_port_delete(rport);
@@ -1416,7 +1435,7 @@ lpfc_drop_node(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
                 lpfc_nlp_counters(phba, ndlp->nlp_state, -1);
         lpfc_delink_node(phba, ndlp);
         spin_unlock_irq(phba->host->host_lock);
-        lpfc_nlp_remove(phba, ndlp);
+        lpfc_nlp_put(ndlp);
 }
 
 /*
@@ -1654,6 +1673,7 @@ lpfc_freenode(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp)
                         }
                         list_del(&mb->list);
                         mempool_free(mb, phba->mbox_mem_pool);
+                        lpfc_nlp_put(ndlp);
                 }
         }
         spin_unlock_irq(phba->host->host_lock);
@@ -1679,8 +1699,8 @@ lpfc_freenode(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp)
  * If we are in the middle of using the nlp in the discovery state
  * machine, defer the free till we reach the end of the state machine.
  */
-int
-lpfc_nlp_remove(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp)
+static void
+lpfc_nlp_remove(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
 {
         struct lpfc_rport_data *rdata;
 
@@ -1688,22 +1708,14 @@ lpfc_nlp_remove(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp)
                 lpfc_cancel_retry_delay_tmo(phba, ndlp);
         }
 
-        if (ndlp->nlp_disc_refcnt) {
-                spin_lock_irq(phba->host->host_lock);
-                ndlp->nlp_flag |= NLP_DELAY_REMOVE;
-                spin_unlock_irq(phba->host->host_lock);
-        } else {
-                lpfc_freenode(phba, ndlp);
-
-                if ((ndlp->rport) && !(phba->fc_flag & FC_UNLOADING)) {
-                        rdata = ndlp->rport->dd_data;
-                        rdata->pnode = NULL;
-                        ndlp->rport = NULL;
-                }
+        lpfc_freenode(phba, ndlp);
 
-                mempool_free( ndlp, phba->nlp_mem_pool);
+        if ((ndlp->rport) && !(phba->fc_flag & FC_UNLOADING)) {
+                put_device(&ndlp->rport->dev);
+                rdata = ndlp->rport->dd_data;
+                rdata->pnode = NULL;
+                ndlp->rport = NULL;
         }
-        return 0;
 }
 
 static int
@@ -2069,14 +2081,14 @@ lpfc_disc_flush_list(struct lpfc_hba * phba)
                 list_for_each_entry_safe(ndlp, next_ndlp, &phba->fc_plogi_list,
                                         nlp_listp) {
                         lpfc_free_tx(phba, ndlp);
-                        lpfc_nlp_remove(phba, ndlp);
+                        lpfc_nlp_put(ndlp);
                 }
         }
         if (phba->fc_adisc_cnt) {
                 list_for_each_entry_safe(ndlp, next_ndlp, &phba->fc_adisc_list,
                                         nlp_listp) {
                         lpfc_free_tx(phba, ndlp);
-                        lpfc_nlp_remove(phba, ndlp);
+                        lpfc_nlp_put(ndlp);
                 }
         }
         return;
@@ -2195,7 +2207,7 @@ lpfc_disc_timeout_handler(struct lpfc_hba *phba)
                 /* Next look for NameServer ndlp */
                 ndlp = lpfc_findnode_did(phba, NLP_SEARCH_ALL, NameServer_DID);
                 if (ndlp)
-                        lpfc_nlp_remove(phba, ndlp);
+                        lpfc_nlp_put(ndlp);
                 /* Start discovery */
                 lpfc_disc_start(phba);
                 break;
@@ -2373,9 +2385,11 @@ lpfc_mbx_cmpl_fdmi_reg_login(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmb)
                 mod_timer(&phba->fc_fdmitmo, jiffies + HZ * 60);
         }
 
+                                /* Mailbox took a reference to the node */
+        lpfc_nlp_put(ndlp);
         lpfc_mbuf_free(phba, mp->virt, mp->phys);
         kfree(mp);
-        mempool_free( pmb, phba->mbox_mem_pool);
+        mempool_free(pmb, phba->mbox_mem_pool);
 
         return;
 }
@@ -2460,8 +2474,7 @@ lpfc_findnode_wwpn(struct lpfc_hba * phba, uint32_t order,
 }
 
 void
-lpfc_nlp_init(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp,
-                 uint32_t did)
+lpfc_nlp_init(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp, uint32_t did)
 {
         memset(ndlp, 0, sizeof (struct lpfc_nodelist));
         INIT_LIST_HEAD(&ndlp->els_retry_evt.evt_listp);
@@ -2471,5 +2484,29 @@ lpfc_nlp_init(struct lpfc_hba * phba, struct lpfc_nodelist * ndlp,
         ndlp->nlp_DID = did;
         ndlp->nlp_phba = phba;
         ndlp->nlp_sid = NLP_NO_SID;
+        kref_init(&ndlp->kref);
         return;
 }
+
+void
+lpfc_nlp_release(struct kref *kref)
+{
+        struct lpfc_nodelist *ndlp = container_of(kref, struct lpfc_nodelist,
+                                                  kref);
+        lpfc_nlp_remove(ndlp->nlp_phba, ndlp);
+        mempool_free(ndlp, ndlp->nlp_phba->nlp_mem_pool);
+}
+
+struct lpfc_nodelist *
+lpfc_nlp_get(struct lpfc_nodelist *ndlp)
+{
+        if (ndlp)
+                kref_get(&ndlp->kref);
+        return ndlp;
+}
+
+int
+lpfc_nlp_put(struct lpfc_nodelist *ndlp)
+{
+        return ndlp ? kref_put(&ndlp->kref, lpfc_nlp_release) : 0;
+}