Merge branch 'for-next' into for-linus
[safe/jmp/linux-2.6] / drivers / scsi / lpfc / lpfc_els.c
index f5e0024..2a40a6e 100644 (file)
@@ -1,7 +1,7 @@
 /*******************************************************************
  * This file is part of the Emulex Linux Device Driver for         *
  * Fibre Channel Host Bus Adapters.                                *
- * Copyright (C) 2004-2007 Emulex.  All rights reserved.           *
+ * Copyright (C) 2004-2009 Emulex.  All rights reserved.           *
  * EMULEX and SLI are trademarks of Emulex.                        *
  * www.emulex.com                                                  *
  * Portions Copyright (C) 2004-2005 Christoph Hellwig              *
@@ -18,7 +18,7 @@
  * more details, a copy of which can be found in the file COPYING  *
  * included with this package.                                     *
  *******************************************************************/
-
+/* See Fibre Channel protocol T11 FC-LS for details */
 #include <linux/blkdev.h>
 #include <linux/pci.h>
 #include <linux/interrupt.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_transport_fc.h>
 
+#include "lpfc_hw4.h"
 #include "lpfc_hw.h"
 #include "lpfc_sli.h"
+#include "lpfc_sli4.h"
+#include "lpfc_nl.h"
 #include "lpfc_disc.h"
 #include "lpfc_scsi.h"
 #include "lpfc.h"
@@ -47,12 +50,31 @@ static int lpfc_issue_els_fdisc(struct lpfc_vport *vport,
                                struct lpfc_nodelist *ndlp, uint8_t retry);
 static int lpfc_issue_fabric_iocb(struct lpfc_hba *phba,
                                  struct lpfc_iocbq *iocb);
-static void lpfc_register_new_vport(struct lpfc_hba *phba,
-                                   struct lpfc_vport *vport,
-                                   struct lpfc_nodelist *ndlp);
 
 static int lpfc_max_els_tries = 3;
 
+/**
+ * lpfc_els_chk_latt - Check host link attention event for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine checks whether there is an outstanding host link
+ * attention event during the discovery process with the @vport. It is done
+ * by reading the HBA's Host Attention (HA) register. If there is any host
+ * link attention events during this @vport's discovery process, the @vport
+ * shall be marked as FC_ABORT_DISCOVERY, a host link attention clear shall
+ * be issued if the link state is not already in host link cleared state,
+ * and a return code shall indicate whether the host link attention event
+ * had happened.
+ *
+ * Note that, if either the host link is in state LPFC_LINK_DOWN or @vport
+ * state in LPFC_VPORT_READY, the request for checking host link attention
+ * event will be ignored and a return code shall indicate no host link
+ * attention event had happened.
+ *
+ * Return codes
+ *   0 - no host link attention event happened
+ *   1 - host link attention event happened
+ **/
 int
 lpfc_els_chk_latt(struct lpfc_vport *vport)
 {
@@ -61,7 +83,8 @@ lpfc_els_chk_latt(struct lpfc_vport *vport)
        uint32_t ha_copy;
 
        if (vport->port_state >= LPFC_VPORT_READY ||
-           phba->link_state == LPFC_LINK_DOWN)
+           phba->link_state == LPFC_LINK_DOWN ||
+           phba->sli_rev > LPFC_SLI_REV3)
                return 0;
 
        /* Read the HBA Host Attention Register */
@@ -92,7 +115,35 @@ lpfc_els_chk_latt(struct lpfc_vport *vport)
        return 1;
 }
 
-static struct lpfc_iocbq *
+/**
+ * lpfc_prep_els_iocb - Allocate and prepare a lpfc iocb data structure
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @expectRsp: flag indicating whether response is expected.
+ * @cmdSize: size of the ELS command.
+ * @retry: number of retries to the command IOCB when it fails.
+ * @ndlp: pointer to a node-list data structure.
+ * @did: destination identifier.
+ * @elscmd: the ELS command code.
+ *
+ * This routine is used for allocating a lpfc-IOCB data structure from
+ * the driver lpfc-IOCB free-list and prepare the IOCB with the parameters
+ * passed into the routine for discovery state machine to issue an Extended
+ * Link Service (ELS) commands. It is a generic lpfc-IOCB allocation
+ * and preparation routine that is used by all the discovery state machine
+ * routines and the ELS command-specific fields will be later set up by
+ * the individual discovery machine routines after calling this routine
+ * allocating and preparing a generic IOCB data structure. It fills in the
+ * Buffer Descriptor Entries (BDEs), allocates buffers for both command
+ * payload and response payload (if expected). The reference count on the
+ * ndlp is incremented by 1 and the reference to the ndlp is put into
+ * context1 of the IOCB data structure for this IOCB to hold the ndlp
+ * reference for the command's callback function to access later.
+ *
+ * Return code
+ *   Pointer to the newly allocated/prepared els iocb data structure
+ *   NULL - when els iocb data structure allocation/preparation failed
+ **/
+struct lpfc_iocbq *
 lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
                   uint16_t cmdSize, uint8_t retry,
                   struct lpfc_nodelist *ndlp, uint32_t did,
@@ -113,6 +164,33 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
 
        if (elsiocb == NULL)
                return NULL;
+
+       /*
+        * If this command is for fabric controller and HBA running
+        * in FIP mode send FLOGI, FDISC and LOGO as FIP frames.
+        */
+       if ((did == Fabric_DID) &&
+               (phba->hba_flag & HBA_FIP_SUPPORT) &&
+               ((elscmd == ELS_CMD_FLOGI) ||
+                (elscmd == ELS_CMD_FDISC) ||
+                (elscmd == ELS_CMD_LOGO)))
+               switch (elscmd) {
+               case ELS_CMD_FLOGI:
+               elsiocb->iocb_flag |= ((ELS_ID_FLOGI << LPFC_FIP_ELS_ID_SHIFT)
+                                       & LPFC_FIP_ELS_ID_MASK);
+               break;
+               case ELS_CMD_FDISC:
+               elsiocb->iocb_flag |= ((ELS_ID_FDISC << LPFC_FIP_ELS_ID_SHIFT)
+                                       & LPFC_FIP_ELS_ID_MASK);
+               break;
+               case ELS_CMD_LOGO:
+               elsiocb->iocb_flag |= ((ELS_ID_LOGO << LPFC_FIP_ELS_ID_SHIFT)
+                                       & LPFC_FIP_ELS_ID_MASK);
+               break;
+               }
+       else
+               elsiocb->iocb_flag &= ~LPFC_FIP_ELS_ID_MASK;
+
        icmd = &elsiocb->iocb;
 
        /* fill in BDEs for command */
@@ -120,12 +198,8 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
        pcmd = kmalloc(sizeof(struct lpfc_dmabuf), GFP_KERNEL);
        if (pcmd)
                pcmd->virt = lpfc_mbuf_alloc(phba, MEM_PRI, &pcmd->phys);
-       if (!pcmd || !pcmd->virt) {
-               kfree(pcmd);
-
-               lpfc_sli_release_iocbq(phba, elsiocb);
-               return NULL;
-       }
+       if (!pcmd || !pcmd->virt)
+               goto els_iocb_free_pcmb_exit;
 
        INIT_LIST_HEAD(&pcmd->list);
 
@@ -135,38 +209,25 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
                if (prsp)
                        prsp->virt = lpfc_mbuf_alloc(phba, MEM_PRI,
                                                     &prsp->phys);
-               if (!prsp || !prsp->virt) {
-                       kfree(prsp);
-                       lpfc_mbuf_free(phba, pcmd->virt, pcmd->phys);
-                       kfree(pcmd);
-                       lpfc_sli_release_iocbq(phba, elsiocb);
-                       return NULL;
-               }
+               if (!prsp || !prsp->virt)
+                       goto els_iocb_free_prsp_exit;
                INIT_LIST_HEAD(&prsp->list);
-       } else {
+       } else
                prsp = NULL;
-       }
 
        /* Allocate buffer for Buffer ptr list */
        pbuflist = kmalloc(sizeof(struct lpfc_dmabuf), GFP_KERNEL);
        if (pbuflist)
                pbuflist->virt = lpfc_mbuf_alloc(phba, MEM_PRI,
                                                 &pbuflist->phys);
-       if (!pbuflist || !pbuflist->virt) {
-               lpfc_sli_release_iocbq(phba, elsiocb);
-               lpfc_mbuf_free(phba, pcmd->virt, pcmd->phys);
-               lpfc_mbuf_free(phba, prsp->virt, prsp->phys);
-               kfree(pcmd);
-               kfree(prsp);
-               kfree(pbuflist);
-               return NULL;
-       }
+       if (!pbuflist || !pbuflist->virt)
+               goto els_iocb_free_pbuf_exit;
 
        INIT_LIST_HEAD(&pbuflist->list);
 
        icmd->un.elsreq64.bdl.addrHigh = putPaddrHigh(pbuflist->phys);
        icmd->un.elsreq64.bdl.addrLow = putPaddrLow(pbuflist->phys);
-       icmd->un.elsreq64.bdl.bdeFlags = BUFF_TYPE_BDL;
+       icmd->un.elsreq64.bdl.bdeFlags = BUFF_TYPE_BLP_64;
        icmd->un.elsreq64.remoteID = did;       /* DID */
        if (expectRsp) {
                icmd->un.elsreq64.bdl.bdeSize = (2 * sizeof(struct ulp_bde64));
@@ -184,9 +245,13 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
                icmd->un.elsreq64.myID = vport->fc_myDID;
 
                /* For ELS_REQUEST64_CR, use the VPI by default */
-               icmd->ulpContext = vport->vpi;
+               icmd->ulpContext = vport->vpi + phba->vpi_base;
                icmd->ulpCt_h = 0;
-               icmd->ulpCt_l = 1;
+               /* The CT field must be 0=INVALID_RPI for the ECHO cmd */
+               if (elscmd == ELS_CMD_ECHO)
+                       icmd->ulpCt_l = 0; /* context = invalid RPI */
+               else
+                       icmd->ulpCt_l = 1; /* context = VPI */
        }
 
        bpl = (struct ulp_bde64 *) pbuflist->virt;
@@ -201,11 +266,14 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
                bpl->addrLow = le32_to_cpu(putPaddrLow(prsp->phys));
                bpl->addrHigh = le32_to_cpu(putPaddrHigh(prsp->phys));
                bpl->tus.f.bdeSize = FCELSSIZE;
-               bpl->tus.f.bdeFlags = BUFF_USE_RCV;
+               bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                bpl->tus.w = le32_to_cpu(bpl->tus.w);
        }
 
+       /* prevent preparing iocb with NULL ndlp reference */
        elsiocb->context1 = lpfc_nlp_get(ndlp);
+       if (!elsiocb->context1)
+               goto els_iocb_free_pbuf_exit;
        elsiocb->context2 = pcmd;
        elsiocb->context3 = pbuflist;
        elsiocb->retry = retry;
@@ -231,10 +299,39 @@ lpfc_prep_els_iocb(struct lpfc_vport *vport, uint8_t expectRsp,
                                 cmdSize);
        }
        return elsiocb;
-}
 
+els_iocb_free_pbuf_exit:
+       if (expectRsp)
+               lpfc_mbuf_free(phba, prsp->virt, prsp->phys);
+       kfree(pbuflist);
 
-static int
+els_iocb_free_prsp_exit:
+       lpfc_mbuf_free(phba, pcmd->virt, pcmd->phys);
+       kfree(prsp);
+
+els_iocb_free_pcmb_exit:
+       kfree(pcmd);
+       lpfc_sli_release_iocbq(phba, elsiocb);
+       return NULL;
+}
+
+/**
+ * lpfc_issue_fabric_reglogin - Issue fabric registration login for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues a fabric registration login for a @vport. An
+ * active ndlp node with Fabric_DID must already exist for this @vport.
+ * The routine invokes two mailbox commands to carry out fabric registration
+ * login through the HBA firmware: the first mailbox command requests the
+ * HBA to perform link configuration for the @vport; and the second mailbox
+ * command requests the HBA to perform the actual fabric registration login
+ * with the @vport.
+ *
+ * Return code
+ *   0 - successfully issued fabric registration login for @vport
+ *   -ENXIO -- failed to issue fabric registration login for @vport
+ **/
+int
 lpfc_issue_fabric_reglogin(struct lpfc_vport *vport)
 {
        struct lpfc_hba  *phba = vport->phba;
@@ -247,7 +344,7 @@ lpfc_issue_fabric_reglogin(struct lpfc_vport *vport)
 
        sp = &phba->fc_fabparam;
        ndlp = lpfc_findnode_did(vport, Fabric_DID);
-       if (!ndlp) {
+       if (!ndlp || !NLP_CHK_NODE_ACT(ndlp)) {
                err = 1;
                goto fail;
        }
@@ -274,8 +371,7 @@ lpfc_issue_fabric_reglogin(struct lpfc_vport *vport)
                err = 4;
                goto fail;
        }
-       rc = lpfc_reg_login(phba, vport->vpi, Fabric_DID, (uint8_t *)sp, mbox,
-                           0);
+       rc = lpfc_reg_rpi(phba, vport->vpi, Fabric_DID, (uint8_t *)sp, mbox, 0);
        if (rc) {
                err = 5;
                goto fail_free_mbox;
@@ -283,6 +379,9 @@ lpfc_issue_fabric_reglogin(struct lpfc_vport *vport)
 
        mbox->mbox_cmpl = lpfc_mbx_cmpl_fabric_reg_login;
        mbox->vport = vport;
+       /* increment the reference count on ndlp to hold reference
+        * for the callback routine.
+        */
        mbox->context2 = lpfc_nlp_get(ndlp);
 
        rc = lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT);
@@ -294,6 +393,9 @@ lpfc_issue_fabric_reglogin(struct lpfc_vport *vport)
        return 0;
 
 fail_issue_reg_login:
+       /* decrement the reference count on ndlp just incremented
+        * for the failed mbox command.
+        */
        lpfc_nlp_put(ndlp);
        mp = (struct lpfc_dmabuf *) mbox->context1;
        lpfc_mbuf_free(phba, mp->virt, mp->phys);
@@ -308,6 +410,95 @@ fail:
        return -ENXIO;
 }
 
+/**
+ * lpfc_issue_reg_vfi - Register VFI for this vport's fabric login
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues a REG_VFI mailbox for the vfi, vpi, fcfi triplet for
+ * the @vport. This mailbox command is necessary for FCoE only.
+ *
+ * Return code
+ *   0 - successfully issued REG_VFI for @vport
+ *   A failure code otherwise.
+ **/
+static int
+lpfc_issue_reg_vfi(struct lpfc_vport *vport)
+{
+       struct lpfc_hba  *phba = vport->phba;
+       LPFC_MBOXQ_t *mboxq;
+       struct lpfc_nodelist *ndlp;
+       struct serv_parm *sp;
+       struct lpfc_dmabuf *dmabuf;
+       int rc = 0;
+
+       sp = &phba->fc_fabparam;
+       ndlp = lpfc_findnode_did(vport, Fabric_DID);
+       if (!ndlp || !NLP_CHK_NODE_ACT(ndlp)) {
+               rc = -ENODEV;
+               goto fail;
+       }
+
+       dmabuf = kzalloc(sizeof(struct lpfc_dmabuf), GFP_KERNEL);
+       if (!dmabuf) {
+               rc = -ENOMEM;
+               goto fail;
+       }
+       dmabuf->virt = lpfc_mbuf_alloc(phba, MEM_PRI, &dmabuf->phys);
+       if (!dmabuf->virt) {
+               rc = -ENOMEM;
+               goto fail_free_dmabuf;
+       }
+       mboxq = mempool_alloc(phba->mbox_mem_pool, GFP_KERNEL);
+       if (!mboxq) {
+               rc = -ENOMEM;
+               goto fail_free_coherent;
+       }
+       vport->port_state = LPFC_FABRIC_CFG_LINK;
+       memcpy(dmabuf->virt, &phba->fc_fabparam, sizeof(vport->fc_sparam));
+       lpfc_reg_vfi(mboxq, vport, dmabuf->phys);
+       mboxq->mbox_cmpl = lpfc_mbx_cmpl_reg_vfi;
+       mboxq->vport = vport;
+       mboxq->context1 = dmabuf;
+       rc = lpfc_sli_issue_mbox(phba, mboxq, MBX_NOWAIT);
+       if (rc == MBX_NOT_FINISHED) {
+               rc = -ENXIO;
+               goto fail_free_mbox;
+       }
+       return 0;
+
+fail_free_mbox:
+       mempool_free(mboxq, phba->mbox_mem_pool);
+fail_free_coherent:
+       lpfc_mbuf_free(phba, dmabuf->virt, dmabuf->phys);
+fail_free_dmabuf:
+       kfree(dmabuf);
+fail:
+       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+       lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+               "0289 Issue Register VFI failed: Err %d\n", rc);
+       return rc;
+}
+
+/**
+ * lpfc_cmpl_els_flogi_fabric - Completion function for flogi to a fabric port
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @sp: pointer to service parameter data structure.
+ * @irsp: pointer to the IOCB within the lpfc response IOCB.
+ *
+ * This routine is invoked by the lpfc_cmpl_els_flogi() completion callback
+ * function to handle the completion of a Fabric Login (FLOGI) into a fabric
+ * port in a fabric topology. It properly sets up the parameters to the @ndlp
+ * from the IOCB response. It also check the newly assigned N_Port ID to the
+ * @vport against the previously assigned N_Port ID. If it is different from
+ * the previously assigned Destination ID (DID), the lpfc_unreg_rpi() routine
+ * is invoked on all the remaining nodes with the @vport to unregister the
+ * Remote Port Indicators (RPIs). Finally, the lpfc_issue_fabric_reglogin()
+ * is invoked to register login to the fabric.
+ *
+ * Return code
+ *   0 - Success (currently, always return 0)
+ **/
 static int
 lpfc_cmpl_els_flogi_fabric(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                           struct serv_parm *sp, IOCB_t *irsp)
@@ -382,6 +573,8 @@ lpfc_cmpl_els_flogi_fabric(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                 */
                list_for_each_entry_safe(np, next_np,
                                        &vport->fc_nodes, nlp_listp) {
+                       if (!NLP_CHK_NODE_ACT(np))
+                               continue;
                        if ((np->nlp_state != NLP_STE_NPR_NODE) ||
                                   !(np->nlp_flag & NLP_NPR_ADISC))
                                continue;
@@ -392,25 +585,62 @@ lpfc_cmpl_els_flogi_fabric(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                }
                if (phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) {
                        lpfc_mbx_unreg_vpi(vport);
+                       spin_lock_irq(shost->host_lock);
                        vport->fc_flag |= FC_VPORT_NEEDS_REG_VPI;
+                       spin_unlock_irq(shost->host_lock);
+               }
+               /*
+                * If VPI is unreged, driver need to do INIT_VPI
+                * before re-registering
+                */
+               if (phba->sli_rev == LPFC_SLI_REV4) {
+                       spin_lock_irq(shost->host_lock);
+                       vport->fc_flag |= FC_VPORT_NEEDS_INIT_VPI;
+                       spin_unlock_irq(shost->host_lock);
                }
        }
 
-       ndlp->nlp_sid = irsp->un.ulpWord[4] & Mask_DID;
-       lpfc_nlp_set_state(vport, ndlp, NLP_STE_REG_LOGIN_ISSUE);
-
-       if (phba->sli3_options & LPFC_SLI3_NPIV_ENABLED &&
-           vport->fc_flag & FC_VPORT_NEEDS_REG_VPI) {
-               lpfc_register_new_vport(phba, vport, ndlp);
-               return 0;
+       if (phba->sli_rev < LPFC_SLI_REV4) {
+               lpfc_nlp_set_state(vport, ndlp, NLP_STE_REG_LOGIN_ISSUE);
+               if (phba->sli3_options & LPFC_SLI3_NPIV_ENABLED &&
+                   vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)
+                       lpfc_register_new_vport(phba, vport, ndlp);
+               else
+                       lpfc_issue_fabric_reglogin(vport);
+       } else {
+               ndlp->nlp_type |= NLP_FABRIC;
+               lpfc_nlp_set_state(vport, ndlp, NLP_STE_UNMAPPED_NODE);
+               if ((!(vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)) &&
+                       (vport->vpi_state & LPFC_VPI_REGISTERED)) {
+                       lpfc_start_fdiscs(phba);
+                       lpfc_do_scr_ns_plogi(phba, vport);
+               } else if (vport->fc_flag & FC_VFI_REGISTERED)
+                       lpfc_issue_init_vpi(vport);
+               else
+                       lpfc_issue_reg_vfi(vport);
        }
-       lpfc_issue_fabric_reglogin(vport);
        return 0;
 }
-
-/*
- * We FLOGIed into an NPort, initiate pt2pt protocol
- */
+/**
+ * lpfc_cmpl_els_flogi_nport - Completion function for flogi to an N_Port
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @sp: pointer to service parameter data structure.
+ *
+ * This routine is invoked by the lpfc_cmpl_els_flogi() completion callback
+ * function to handle the completion of a Fabric Login (FLOGI) into an N_Port
+ * in a point-to-point topology. First, the @vport's N_Port Name is compared
+ * with the received N_Port Name: if the @vport's N_Port Name is greater than
+ * the received N_Port Name lexicographically, this node shall assign local
+ * N_Port ID (PT2PT_LocalID: 1) and remote N_Port ID (PT2PT_RemoteID: 2) and
+ * will send out Port Login (PLOGI) with the N_Port IDs assigned. Otherwise,
+ * this node shall just wait for the remote node to issue PLOGI and assign
+ * N_Port IDs.
+ *
+ * Return code
+ *   0 - Success
+ *   -ENXIO - Fail
+ **/
 static int
 lpfc_cmpl_els_flogi_nport(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                          struct serv_parm *sp)
@@ -456,6 +686,9 @@ lpfc_cmpl_els_flogi_nport(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                        mempool_free(mbox, phba->mbox_mem_pool);
                        goto fail;
                }
+               /* Decrement ndlp reference count indicating that ndlp can be
+                * safely released when other references to it are done.
+                */
                lpfc_nlp_put(ndlp);
 
                ndlp = lpfc_findnode_did(vport, PT2PT_RemoteID);
@@ -467,22 +700,32 @@ lpfc_cmpl_els_flogi_nport(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                        ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
                        if (!ndlp)
                                goto fail;
-
                        lpfc_nlp_init(vport, ndlp, PT2PT_RemoteID);
+               } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+                       ndlp = lpfc_enable_node(vport, ndlp,
+                                               NLP_STE_UNUSED_NODE);
+                       if(!ndlp)
+                               goto fail;
                }
 
                memcpy(&ndlp->nlp_portname, &sp->portName,
                       sizeof(struct lpfc_name));
                memcpy(&ndlp->nlp_nodename, &sp->nodeName,
                       sizeof(struct lpfc_name));
+               /* Set state will put ndlp onto node list if not already done */
                lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
                spin_lock_irq(shost->host_lock);
                ndlp->nlp_flag |= NLP_NPR_2B_DISC;
                spin_unlock_irq(shost->host_lock);
-       } else {
-               /* This side will wait for the PLOGI */
+       } else
+               /* This side will wait for the PLOGI, decrement ndlp reference
+                * count indicating that ndlp can be released when other
+                * references to it are done.
+                */
                lpfc_nlp_put(ndlp);
-       }
+
+       /* If we are pt2pt with another NPort, force NPIV off! */
+       phba->sli3_options &= ~LPFC_SLI3_NPIV_ENABLED;
 
        spin_lock_irq(shost->host_lock);
        vport->fc_flag |= FC_PT2PT;
@@ -495,6 +738,29 @@ fail:
        return -ENXIO;
 }
 
+/**
+ * lpfc_cmpl_els_flogi - Completion callback function for flogi
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the top-level completion callback function for issuing
+ * a Fabric Login (FLOGI) command. If the response IOCB reported error,
+ * the lpfc_els_retry() routine shall be invoked to retry the FLOGI. If
+ * retry has been made (either immediately or delayed with lpfc_els_retry()
+ * returning 1), the command IOCB will be released and function returned.
+ * If the retry attempt has been given up (possibly reach the maximum
+ * number of retries), one additional decrement of ndlp reference shall be
+ * invoked before going out after releasing the command IOCB. This will
+ * actually release the remote node (Note, lpfc_els_free_iocb() will also
+ * invoke one decrement of ndlp reference count). If no error reported in
+ * the IOCB status, the command Port ID field is used to determine whether
+ * this is a point-to-point topology or a fabric topology: if the Port ID
+ * field is assigned, it is a fabric topology; otherwise, it is a
+ * point-to-point topology. The routine lpfc_cmpl_els_flogi_fabric() or
+ * lpfc_cmpl_els_flogi_nport() shall be invoked accordingly to handle the
+ * specific topology completion conditions.
+ **/
 static void
 lpfc_cmpl_els_flogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                    struct lpfc_iocbq *rspiocb)
@@ -509,6 +775,9 @@ lpfc_cmpl_els_flogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 
        /* Check to see if link went down during discovery */
        if (lpfc_els_chk_latt(vport)) {
+               /* One additional decrement on node reference count to
+                * trigger the release of the node
+                */
                lpfc_nlp_put(ndlp);
                goto out;
        }
@@ -544,6 +813,9 @@ lpfc_cmpl_els_flogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                                 irsp->ulpTimeout);
                goto flogifail;
        }
+       spin_lock_irq(shost->host_lock);
+       vport->fc_flag &= ~FC_VPORT_CVL_RCVD;
+       spin_unlock_irq(shost->host_lock);
 
        /*
         * The FLogI succeeded.  Sync the data for the CPU before
@@ -555,7 +827,7 @@ lpfc_cmpl_els_flogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 
        /* FLOGI completes successfully */
        lpfc_printf_vlog(vport, KERN_INFO, LOG_ELS,
-                        "0101 FLOGI completes sucessfully "
+                        "0101 FLOGI completes successfully "
                         "Data: x%x x%x x%x x%x\n",
                         irsp->un.ulpWord[4], sp->cmn.e_d_tov,
                         sp->cmn.w2.r_a_tov, sp->cmn.edtovResolution);
@@ -594,6 +866,28 @@ out:
        lpfc_els_free_iocb(phba, cmdiocb);
 }
 
+/**
+ * lpfc_issue_els_flogi - Issue an flogi iocb command for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues a Fabric Login (FLOGI) Request ELS command
+ * for a @vport. The initiator service parameters are put into the payload
+ * of the FLOGI Request IOCB and the top-level callback function pointer
+ * to lpfc_cmpl_els_flogi() routine is put to the IOCB completion callback
+ * function field. The lpfc_issue_fabric_iocb routine is invoked to send
+ * out FLOGI ELS command with one outstanding fabric IOCB at a time.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the FLOGI ELS command.
+ *
+ * Return code
+ *   0 - successfully issued flogi iocb for @vport
+ *   1 - failed to issue flogi iocb for @vport
+ **/
 static int
 lpfc_issue_els_flogi(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                     uint8_t retry)
@@ -637,9 +931,14 @@ lpfc_issue_els_flogi(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        if (sp->cmn.fcphHigh < FC_PH3)
                sp->cmn.fcphHigh = FC_PH3;
 
-       if (phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) {
+       if  (phba->sli_rev == LPFC_SLI_REV4) {
+               elsiocb->iocb.ulpCt_h = ((SLI4_CT_FCFI >> 1) & 1);
+               elsiocb->iocb.ulpCt_l = (SLI4_CT_FCFI & 1);
+               /* FLOGI needs to be 3 for WQE FCFI */
+               /* Set the fcfi to the fcfi we registered with */
+               elsiocb->iocb.ulpContext = phba->fcf.fcfi;
+       } else if (phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) {
                sp->cmn.request_multiple_Nport = 1;
-
                /* For FLOGI, Let FLOGI rsp set the NPortID for VPI 0 */
                icmd->ulpCt_h = 1;
                icmd->ulpCt_l = 0;
@@ -670,6 +969,20 @@ lpfc_issue_els_flogi(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        return 0;
 }
 
+/**
+ * lpfc_els_abort_flogi - Abort all outstanding flogi iocbs
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine aborts all the outstanding Fabric Login (FLOGI) IOCBs
+ * with a @phba. This routine walks all the outstanding IOCBs on the txcmplq
+ * list and issues an abort IOCB commond on each outstanding IOCB that
+ * contains a active Fabric_DID ndlp. Note that this function is to issue
+ * the abort IOCB command on all the outstanding IOCBs, thus when this
+ * function returns, it does not guarantee all the IOCBs are actually aborted.
+ *
+ * Return code
+ *   0 - Successfully issued abort iocb on all outstanding flogis (Always 0)
+ **/
 int
 lpfc_els_abort_flogi(struct lpfc_hba *phba)
 {
@@ -695,9 +1008,9 @@ lpfc_els_abort_flogi(struct lpfc_hba *phba)
                if (icmd->ulpCommand == CMD_ELS_REQUEST64_CR &&
                    icmd->un.elsreq64.bdl.ulpIoTag32) {
                        ndlp = (struct lpfc_nodelist *)(iocb->context1);
-                       if (ndlp && (ndlp->nlp_DID == Fabric_DID)) {
+                       if (ndlp && NLP_CHK_NODE_ACT(ndlp) &&
+                           (ndlp->nlp_DID == Fabric_DID))
                                lpfc_sli_issue_abort_iotag(phba, pring, iocb);
-                       }
                }
        }
        spin_unlock_irq(&phba->hbalock);
@@ -705,6 +1018,22 @@ lpfc_els_abort_flogi(struct lpfc_hba *phba)
        return 0;
 }
 
+/**
+ * lpfc_initial_flogi - Issue an initial fabric login for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues an initial Fabric Login (FLOGI) for the @vport
+ * specified. It first searches the ndlp with the Fabric_DID (0xfffffe) from
+ * the @vport's ndlp list. If no such ndlp found, it will create an ndlp and
+ * put it into the @vport's ndlp list. If an inactive ndlp found on the list,
+ * it will just be enabled and made active. The lpfc_issue_els_flogi() routine
+ * is then invoked with the @vport and the ndlp to perform the FLOGI for the
+ * @vport.
+ *
+ * Return code
+ *   0 - failed to issue initial flogi for @vport
+ *   1 - successfully issued initial flogi for @vport
+ **/
 int
 lpfc_initial_flogi(struct lpfc_vport *vport)
 {
@@ -722,16 +1051,42 @@ lpfc_initial_flogi(struct lpfc_vport *vport)
                if (!ndlp)
                        return 0;
                lpfc_nlp_init(vport, ndlp, Fabric_DID);
-       } else {
-               lpfc_dequeue_node(vport, ndlp);
+               /* Set the node type */
+               ndlp->nlp_type |= NLP_FABRIC;
+               /* Put ndlp onto node list */
+               lpfc_enqueue_node(vport, ndlp);
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               /* re-setup ndlp without removing from node list */
+               ndlp = lpfc_enable_node(vport, ndlp, NLP_STE_UNUSED_NODE);
+               if (!ndlp)
+                       return 0;
        }
 
-       if (lpfc_issue_els_flogi(vport, ndlp, 0)) {
+       if (lpfc_issue_els_flogi(vport, ndlp, 0))
+               /* This decrement of reference count to node shall kick off
+                * the release of the node.
+                */
                lpfc_nlp_put(ndlp);
-       }
+
        return 1;
 }
 
+/**
+ * lpfc_initial_fdisc - Issue an initial fabric discovery for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues an initial Fabric Discover (FDISC) for the @vport
+ * specified. It first searches the ndlp with the Fabric_DID (0xfffffe) from
+ * the @vport's ndlp list. If no such ndlp found, it will create an ndlp and
+ * put it into the @vport's ndlp list. If an inactive ndlp found on the list,
+ * it will just be enabled and made active. The lpfc_issue_els_fdisc() routine
+ * is then invoked with the @vport and the ndlp to perform the FDISC for the
+ * @vport.
+ *
+ * Return code
+ *   0 - failed to issue initial fdisc for @vport
+ *   1 - successfully issued initial fdisc for @vport
+ **/
 int
 lpfc_initial_fdisc(struct lpfc_vport *vport)
 {
@@ -746,15 +1101,36 @@ lpfc_initial_fdisc(struct lpfc_vport *vport)
                if (!ndlp)
                        return 0;
                lpfc_nlp_init(vport, ndlp, Fabric_DID);
-       } else {
-               lpfc_dequeue_node(vport, ndlp);
+               /* Put ndlp onto node list */
+               lpfc_enqueue_node(vport, ndlp);
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               /* re-setup ndlp without removing from node list */
+               ndlp = lpfc_enable_node(vport, ndlp, NLP_STE_UNUSED_NODE);
+               if (!ndlp)
+                       return 0;
        }
+
        if (lpfc_issue_els_fdisc(vport, ndlp, 0)) {
+               /* decrement node reference count to trigger the release of
+                * the node.
+                */
                lpfc_nlp_put(ndlp);
+               return 0;
        }
        return 1;
 }
 
+/**
+ * lpfc_more_plogi - Check and issue remaining plogis for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine checks whether there are more remaining Port Logins
+ * (PLOGI) to be issued for the @vport. If so, it will invoke the routine
+ * lpfc_els_disc_plogi() to go through the Node Port Recovery (NPR) nodes
+ * to issue ELS PLOGIs up to the configured discover threads with the
+ * @vport (@vport->cfg_discovery_threads). The function also decrement
+ * the @vport's num_disc_node by 1 if it is not already 0.
+ **/
 void
 lpfc_more_plogi(struct lpfc_vport *vport)
 {
@@ -777,6 +1153,37 @@ lpfc_more_plogi(struct lpfc_vport *vport)
        return;
 }
 
+/**
+ * lpfc_plogi_confirm_nport - Confirm pologi wwpn matches stored ndlp
+ * @phba: pointer to lpfc hba data structure.
+ * @prsp: pointer to response IOCB payload.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine checks and indicates whether the WWPN of an N_Port, retrieved
+ * from a PLOGI, matches the WWPN that is stored in the @ndlp for that N_POrt.
+ * The following cases are considered N_Port confirmed:
+ * 1) The N_Port is a Fabric ndlp; 2) The @ndlp is on vport list and matches
+ * the WWPN of the N_Port logged into; 3) The @ndlp is not on vport list but
+ * it does not have WWPN assigned either. If the WWPN is confirmed, the
+ * pointer to the @ndlp will be returned. If the WWPN is not confirmed:
+ * 1) if there is a node on vport list other than the @ndlp with the same
+ * WWPN of the N_Port PLOGI logged into, the lpfc_unreg_rpi() will be invoked
+ * on that node to release the RPI associated with the node; 2) if there is
+ * no node found on vport list with the same WWPN of the N_Port PLOGI logged
+ * into, a new node shall be allocated (or activated). In either case, the
+ * parameters of the @ndlp shall be copied to the new_ndlp, the @ndlp shall
+ * be released and the new_ndlp shall be put on to the vport node list and
+ * its pointer returned as the confirmed node.
+ *
+ * Note that before the @ndlp got "released", the keepDID from not-matching
+ * or inactive "new_ndlp" on the vport node list is assigned to the nlp_DID
+ * of the @ndlp. This is because the release of @ndlp is actually to put it
+ * into an inactive state on the vport node list and the vport node list
+ * management algorithm does not allow two node with a same DID.
+ *
+ * Return code
+ *   pointer to the PLOGI N_Port @ndlp
+ **/
 static struct lpfc_nodelist *
 lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
                         struct lpfc_nodelist *ndlp)
@@ -787,7 +1194,7 @@ lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
        struct fc_rport *rport;
        struct serv_parm *sp;
        uint8_t  name[sizeof(struct lpfc_name)];
-       uint32_t rc;
+       uint32_t rc, keepDID = 0;
 
        /* Fabric nodes can have the same WWPN so we don't bother searching
         * by WWPN.  Just return the ndlp that was given to us.
@@ -803,7 +1210,7 @@ lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
         */
        new_ndlp = lpfc_findnode_wwpn(vport, &sp->portName);
 
-       if (new_ndlp == ndlp)
+       if (new_ndlp == ndlp && NLP_CHK_NODE_ACT(new_ndlp))
                return ndlp;
 
        if (!new_ndlp) {
@@ -814,9 +1221,19 @@ lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
                new_ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_ATOMIC);
                if (!new_ndlp)
                        return ndlp;
-
                lpfc_nlp_init(vport, new_ndlp, ndlp->nlp_DID);
-       }
+       } else if (!NLP_CHK_NODE_ACT(new_ndlp)) {
+               rc = memcmp(&ndlp->nlp_portname, name,
+                           sizeof(struct lpfc_name));
+               if (!rc)
+                       return ndlp;
+               new_ndlp = lpfc_enable_node(vport, new_ndlp,
+                                               NLP_STE_UNUSED_NODE);
+               if (!new_ndlp)
+                       return ndlp;
+               keepDID = new_ndlp->nlp_DID;
+       } else
+               keepDID = new_ndlp->nlp_DID;
 
        lpfc_unreg_rpi(vport, new_ndlp);
        new_ndlp->nlp_DID = ndlp->nlp_DID;
@@ -826,6 +1243,7 @@ lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
                new_ndlp->nlp_flag |= NLP_NPR_2B_DISC;
        ndlp->nlp_flag &= ~NLP_NPR_2B_DISC;
 
+       /* Set state will put new_ndlp on to node list if not already done */
        lpfc_nlp_set_state(vport, new_ndlp, ndlp->nlp_state);
 
        /* Move this back to NPR state */
@@ -846,17 +1264,40 @@ lpfc_plogi_confirm_nport(struct lpfc_hba *phba, uint32_t *prsp,
                        }
                        new_ndlp->nlp_type = ndlp->nlp_type;
                }
+               /* We shall actually free the ndlp with both nlp_DID and
+                * nlp_portname fields equals 0 to avoid any ndlp on the
+                * nodelist never to be used.
+                */
+               if (ndlp->nlp_DID == 0) {
+                       spin_lock_irq(&phba->ndlp_lock);
+                       NLP_SET_FREE_REQ(ndlp);
+                       spin_unlock_irq(&phba->ndlp_lock);
+               }
 
+               /* Two ndlps cannot have the same did on the nodelist */
+               ndlp->nlp_DID = keepDID;
                lpfc_drop_node(vport, ndlp);
        }
        else {
                lpfc_unreg_rpi(vport, ndlp);
-               ndlp->nlp_DID = 0; /* Two ndlps cannot have the same did */
+               /* Two ndlps cannot have the same did */
+               ndlp->nlp_DID = keepDID;
                lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
        }
        return new_ndlp;
 }
 
+/**
+ * lpfc_end_rscn - Check and handle more rscn for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine checks whether more Registration State Change
+ * Notifications (RSCNs) came in while the discovery state machine was in
+ * the FC_RSCN_MODE. If so, the lpfc_els_handle_rscn() routine will be
+ * invoked to handle the additional RSCNs for the @vport. Otherwise, the
+ * FC_RSCN_MODE bit will be cleared with the @vport to mark as the end of
+ * handling the RSCNs.
+ **/
 void
 lpfc_end_rscn(struct lpfc_vport *vport)
 {
@@ -878,6 +1319,26 @@ lpfc_end_rscn(struct lpfc_vport *vport)
        }
 }
 
+/**
+ * lpfc_cmpl_els_plogi - Completion callback function for plogi
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function for issuing the Port
+ * Login (PLOGI) command. For PLOGI completion, there must be an active
+ * ndlp on the vport node list that matches the remote node ID from the
+ * PLOGI reponse IOCB. If such ndlp does not exist, the PLOGI is simply
+ * ignored and command IOCB released. The PLOGI response IOCB status is
+ * checked for error conditons. If there is error status reported, PLOGI
+ * retry shall be attempted by invoking the lpfc_els_retry() routine.
+ * Otherwise, the lpfc_plogi_confirm_nport() routine shall be invoked on
+ * the ndlp and the NLP_EVT_CMPL_PLOGI state to the Discover State Machine
+ * (DSM) is set for this PLOGI completion. Finally, it checks whether
+ * there are additional N_Port nodes with the vport that need to perform
+ * PLOGI. If so, the lpfc_more_plogi() routine is invoked to issue addition
+ * PLOGIs.
+ **/
 static void
 lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                    struct lpfc_iocbq *rspiocb)
@@ -899,7 +1360,7 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                irsp->un.elsreq64.remoteID);
 
        ndlp = lpfc_findnode_did(vport, irsp->un.elsreq64.remoteID);
-       if (!ndlp) {
+       if (!ndlp || !NLP_CHK_NODE_ACT(ndlp)) {
                lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
                                 "0136 PLOGI completes to NPort x%x "
                                 "with no ndlp. Data: x%x x%x x%x\n",
@@ -949,12 +1410,11 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                }
                /* PLOGI failed */
                /* Do not call DSM for lpfc_els_abort'ed ELS cmds */
-               if (lpfc_error_lost_link(irsp)) {
+               if (lpfc_error_lost_link(irsp))
                        rc = NLP_STE_FREED_NODE;
-               } else {
+               else
                        rc = lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                                     NLP_EVT_CMPL_PLOGI);
-               }
        } else {
                /* Good status, call state machine */
                prsp = list_entry(((struct lpfc_dmabuf *)
@@ -984,6 +1444,27 @@ out:
        return;
 }
 
+/**
+ * lpfc_issue_els_plogi - Issue an plogi iocb command for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @did: destination port identifier.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues a Port Login (PLOGI) command to a remote N_Port
+ * (with the @did) for a @vport. Before issuing a PLOGI to a remote N_Port,
+ * the ndlp with the remote N_Port DID must exist on the @vport's ndlp list.
+ * This routine constructs the proper feilds of the PLOGI IOCB and invokes
+ * the lpfc_sli_issue_iocb() routine to send out PLOGI ELS command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the PLOGI ELS command.
+ *
+ * Return code
+ *   0 - Successfully issued a plogi for @vport
+ *   1 - failed to issue a plogi for @vport
+ **/
 int
 lpfc_issue_els_plogi(struct lpfc_vport *vport, uint32_t did, uint8_t retry)
 {
@@ -992,18 +1473,18 @@ lpfc_issue_els_plogi(struct lpfc_vport *vport, uint32_t did, uint8_t retry)
        IOCB_t *icmd;
        struct lpfc_nodelist *ndlp;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        int ret;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
 
        ndlp = lpfc_findnode_did(vport, did);
-       /* If ndlp if not NULL, we will bump the reference count on it */
+       if (ndlp && !NLP_CHK_NODE_ACT(ndlp))
+               ndlp = NULL;
 
+       /* If ndlp is not NULL, we will bump the reference count on it */
        cmdsize = (sizeof(uint32_t) + sizeof(struct serv_parm));
        elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp, did,
                                     ELS_CMD_PLOGI);
@@ -1031,7 +1512,7 @@ lpfc_issue_els_plogi(struct lpfc_vport *vport, uint32_t did, uint8_t retry)
 
        phba->fc_stat.elsXmitPLOGI++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_plogi;
-       ret = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       ret = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
 
        if (ret == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
@@ -1040,6 +1521,19 @@ lpfc_issue_els_plogi(struct lpfc_vport *vport, uint32_t did, uint8_t retry)
        return 0;
 }
 
+/**
+ * lpfc_cmpl_els_prli - Completion callback function for prli
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function for a Process Login
+ * (PRLI) ELS command. The PRLI response IOCB status is checked for error
+ * status. If there is error status reported, PRLI retry shall be attempted
+ * by invoking the lpfc_els_retry() routine. Otherwise, the state
+ * NLP_EVT_CMPL_PRLI is sent to the Discover State Machine (DSM) for this
+ * ndlp to mark the PRLI completion.
+ **/
 static void
 lpfc_cmpl_els_prli(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                   struct lpfc_iocbq *rspiocb)
@@ -1084,23 +1578,41 @@ lpfc_cmpl_els_prli(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                }
                /* PRLI failed */
                /* Do not call DSM for lpfc_els_abort'ed ELS cmds */
-               if (lpfc_error_lost_link(irsp)) {
+               if (lpfc_error_lost_link(irsp))
                        goto out;
-               } else {
+               else
                        lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                                NLP_EVT_CMPL_PRLI);
-               }
-       } else {
+       } else
                /* Good status, call state machine */
                lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                        NLP_EVT_CMPL_PRLI);
-       }
-
 out:
        lpfc_els_free_iocb(phba, cmdiocb);
        return;
 }
 
+/**
+ * lpfc_issue_els_prli - Issue a prli iocb command for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues a Process Login (PRLI) ELS command for the
+ * @vport. The PRLI service parameters are set up in the payload of the
+ * PRLI Request command and the pointer to lpfc_cmpl_els_prli() routine
+ * is put to the IOCB completion callback func field before invoking the
+ * routine lpfc_sli_issue_iocb() to send out PRLI command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the PRLI ELS command.
+ *
+ * Return code
+ *   0 - successfully issued prli iocb command for @vport
+ *   1 - failed to issue prli iocb command for @vport
+ **/
 int
 lpfc_issue_els_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                    uint8_t retry)
@@ -1110,14 +1622,9 @@ lpfc_issue_els_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        PRLI *npr;
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
-       struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
 
-       psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
-
        cmdsize = (sizeof(uint32_t) + sizeof(PRLI));
        elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp,
                                     ndlp->nlp_DID, ELS_CMD_PRLI);
@@ -1159,7 +1666,8 @@ lpfc_issue_els_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        spin_lock_irq(shost->host_lock);
        ndlp->nlp_flag |= NLP_PRLI_SND;
        spin_unlock_irq(shost->host_lock);
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
                spin_lock_irq(shost->host_lock);
                ndlp->nlp_flag &= ~NLP_PRLI_SND;
                spin_unlock_irq(shost->host_lock);
@@ -1170,6 +1678,93 @@ lpfc_issue_els_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        return 0;
 }
 
+/**
+ * lpfc_rscn_disc - Perform rscn discovery for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine performs Registration State Change Notification (RSCN)
+ * discovery for a @vport. If the @vport's node port recovery count is not
+ * zero, it will invoke the lpfc_els_disc_plogi() to perform PLOGI for all
+ * the nodes that need recovery. If none of the PLOGI were needed through
+ * the lpfc_els_disc_plogi() routine, the lpfc_end_rscn() routine shall be
+ * invoked to check and handle possible more RSCN came in during the period
+ * of processing the current ones.
+ **/
+static void
+lpfc_rscn_disc(struct lpfc_vport *vport)
+{
+       lpfc_can_disctmo(vport);
+
+       /* RSCN discovery */
+       /* go thru NPR nodes and issue ELS PLOGIs */
+       if (vport->fc_npr_cnt)
+               if (lpfc_els_disc_plogi(vport))
+                       return;
+
+       lpfc_end_rscn(vport);
+}
+
+/**
+ * lpfc_adisc_done - Complete the adisc phase of discovery
+ * @vport: pointer to lpfc_vport hba data structure that finished all ADISCs.
+ *
+ * This function is called when the final ADISC is completed during discovery.
+ * This function handles clearing link attention or issuing reg_vpi depending
+ * on whether npiv is enabled. This function also kicks off the PLOGI phase of
+ * discovery.
+ * This function is called with no locks held.
+ **/
+static void
+lpfc_adisc_done(struct lpfc_vport *vport)
+{
+       struct Scsi_Host   *shost = lpfc_shost_from_vport(vport);
+       struct lpfc_hba   *phba = vport->phba;
+
+       /*
+        * For NPIV, cmpl_reg_vpi will set port_state to READY,
+        * and continue discovery.
+        */
+       if ((phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) &&
+           !(vport->fc_flag & FC_RSCN_MODE) &&
+           (phba->sli_rev < LPFC_SLI_REV4)) {
+               lpfc_issue_reg_vpi(phba, vport);
+               return;
+       }
+       /*
+       * For SLI2, we need to set port_state to READY
+       * and continue discovery.
+       */
+       if (vport->port_state < LPFC_VPORT_READY) {
+               /* If we get here, there is nothing to ADISC */
+               if (vport->port_type == LPFC_PHYSICAL_PORT)
+                       lpfc_issue_clear_la(phba, vport);
+               if (!(vport->fc_flag & FC_ABORT_DISCOVERY)) {
+                       vport->num_disc_nodes = 0;
+                       /* go thru NPR list, issue ELS PLOGIs */
+                       if (vport->fc_npr_cnt)
+                               lpfc_els_disc_plogi(vport);
+                       if (!vport->num_disc_nodes) {
+                               spin_lock_irq(shost->host_lock);
+                               vport->fc_flag &= ~FC_NDISC_ACTIVE;
+                               spin_unlock_irq(shost->host_lock);
+                               lpfc_can_disctmo(vport);
+                               lpfc_end_rscn(vport);
+                       }
+               }
+               vport->port_state = LPFC_VPORT_READY;
+       } else
+               lpfc_rscn_disc(vport);
+}
+
+/**
+ * lpfc_more_adisc - Issue more adisc as needed
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine determines whether there are more ndlps on a @vport
+ * node list need to have Address Discover (ADISC) issued. If so, it will
+ * invoke the lpfc_els_disc_adisc() routine to issue ADISC on the @vport's
+ * remaining nodes which need to have ADISC sent.
+ **/
 void
 lpfc_more_adisc(struct lpfc_vport *vport)
 {
@@ -1189,23 +1784,27 @@ lpfc_more_adisc(struct lpfc_vport *vport)
                /* go thru NPR nodes and issue any remaining ELS ADISCs */
                sentadisc = lpfc_els_disc_adisc(vport);
        }
+       if (!vport->num_disc_nodes)
+               lpfc_adisc_done(vport);
        return;
 }
 
-static void
-lpfc_rscn_disc(struct lpfc_vport *vport)
-{
-       lpfc_can_disctmo(vport);
-
-       /* RSCN discovery */
-       /* go thru NPR nodes and issue ELS PLOGIs */
-       if (vport->fc_npr_cnt)
-               if (lpfc_els_disc_plogi(vport))
-                       return;
-
-       lpfc_end_rscn(vport);
-}
-
+/**
+ * lpfc_cmpl_els_adisc - Completion callback function for adisc
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion function for issuing the Address Discover
+ * (ADISC) command. It first checks to see whether link went down during
+ * the discovery process. If so, the node will be marked as node port
+ * recovery for issuing discover IOCB by the link attention handler and
+ * exit. Otherwise, the response status is checked. If error was reported
+ * in the response status, the ADISC command shall be retried by invoking
+ * the lpfc_els_retry() routine. Otherwise, if no error was reported in
+ * the response status, the state machine is invoked to set transition
+ * with respect to NLP_EVT_CMPL_ADISC event.
+ **/
 static void
 lpfc_cmpl_els_adisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                    struct lpfc_iocbq *rspiocb)
@@ -1262,67 +1861,42 @@ lpfc_cmpl_els_adisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                }
                /* ADISC failed */
                /* Do not call DSM for lpfc_els_abort'ed ELS cmds */
-               if (!lpfc_error_lost_link(irsp)) {
+               if (!lpfc_error_lost_link(irsp))
                        lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                                NLP_EVT_CMPL_ADISC);
-               }
-       } else {
+       } else
                /* Good status, call state machine */
                lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                        NLP_EVT_CMPL_ADISC);
-       }
 
-       if (disc && vport->num_disc_nodes) {
-               /* Check to see if there are more ADISCs to be sent */
+       /* Check to see if there are more ADISCs to be sent */
+       if (disc && vport->num_disc_nodes)
                lpfc_more_adisc(vport);
-
-               /* Check to see if we are done with ADISC authentication */
-               if (vport->num_disc_nodes == 0) {
-                       /* If we get here, there is nothing left to ADISC */
-                       /*
-                        * For NPIV, cmpl_reg_vpi will set port_state to READY,
-                        * and continue discovery.
-                        */
-                       if ((phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) &&
-                          !(vport->fc_flag & FC_RSCN_MODE)) {
-                               lpfc_issue_reg_vpi(phba, vport);
-                               goto out;
-                       }
-                       /*
-                        * For SLI2, we need to set port_state to READY
-                        * and continue discovery.
-                        */
-                       if (vport->port_state < LPFC_VPORT_READY) {
-                               /* If we get here, there is nothing to ADISC */
-                               if (vport->port_type == LPFC_PHYSICAL_PORT)
-                                       lpfc_issue_clear_la(phba, vport);
-
-                               if (!(vport->fc_flag & FC_ABORT_DISCOVERY)) {
-                                       vport->num_disc_nodes = 0;
-                                       /* go thru NPR list, issue ELS PLOGIs */
-                                       if (vport->fc_npr_cnt)
-                                               lpfc_els_disc_plogi(vport);
-
-                                       if (!vport->num_disc_nodes) {
-                                               spin_lock_irq(shost->host_lock);
-                                               vport->fc_flag &=
-                                                       ~FC_NDISC_ACTIVE;
-                                               spin_unlock_irq(
-                                                       shost->host_lock);
-                                               lpfc_can_disctmo(vport);
-                                       }
-                               }
-                               vport->port_state = LPFC_VPORT_READY;
-                       } else {
-                               lpfc_rscn_disc(vport);
-                       }
-               }
-       }
 out:
        lpfc_els_free_iocb(phba, cmdiocb);
        return;
 }
 
+/**
+ * lpfc_issue_els_adisc - Issue an address discover iocb to an node on a vport
+ * @vport: pointer to a virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues an Address Discover (ADISC) for an @ndlp on a
+ * @vport. It prepares the payload of the ADISC ELS command, updates the
+ * and states of the ndlp, and invokes the lpfc_sli_issue_iocb() routine
+ * to issue the ADISC ELS command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the ADISC ELS command.
+ *
+ * Return code
+ *   0 - successfully issued adisc
+ *   1 - failed to issue adisc
+ **/
 int
 lpfc_issue_els_adisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                     uint8_t retry)
@@ -1332,8 +1906,6 @@ lpfc_issue_els_adisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        ADISC *ap;
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli *psli = &phba->sli;
-       struct lpfc_sli_ring *pring = &psli->ring[LPFC_ELS_RING];
        uint8_t *pcmd;
        uint16_t cmdsize;
 
@@ -1366,7 +1938,8 @@ lpfc_issue_els_adisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        spin_lock_irq(shost->host_lock);
        ndlp->nlp_flag |= NLP_ADISC_SND;
        spin_unlock_irq(shost->host_lock);
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
                spin_lock_irq(shost->host_lock);
                ndlp->nlp_flag &= ~NLP_ADISC_SND;
                spin_unlock_irq(shost->host_lock);
@@ -1376,6 +1949,18 @@ lpfc_issue_els_adisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        return 0;
 }
 
+/**
+ * lpfc_cmpl_els_logo - Completion callback function for logo
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion function for issuing the ELS Logout (LOGO)
+ * command. If no error status was reported from the LOGO response, the
+ * state machine of the associated ndlp shall be invoked for transition with
+ * respect to NLP_EVT_CMPL_LOGO event. Otherwise, if error status was reported,
+ * the lpfc_els_retry() routine will be invoked to retry the LOGO command.
+ **/
 static void
 lpfc_cmpl_els_logo(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                   struct lpfc_iocbq *rspiocb)
@@ -1430,19 +2015,37 @@ lpfc_cmpl_els_logo(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                else
                        lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                                NLP_EVT_CMPL_LOGO);
-       } else {
+       } else
                /* Good status, call state machine.
                 * This will unregister the rpi if needed.
                 */
                lpfc_disc_state_machine(vport, ndlp, cmdiocb,
                                        NLP_EVT_CMPL_LOGO);
-       }
-
 out:
        lpfc_els_free_iocb(phba, cmdiocb);
        return;
 }
 
+/**
+ * lpfc_issue_els_logo - Issue a logo to an node on a vport
+ * @vport: pointer to a virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine constructs and issues an ELS Logout (LOGO) iocb command
+ * to a remote node, referred by an @ndlp on a @vport. It constructs the
+ * payload of the IOCB, properly sets up the @ndlp state, and invokes the
+ * lpfc_sli_issue_iocb() routine to send out the LOGO ELS command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the LOGO ELS command.
+ *
+ * Return code
+ *   0 - successfully issued logo
+ *   1 - failed to issue logo
+ **/
 int
 lpfc_issue_els_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                    uint8_t retry)
@@ -1451,15 +2054,10 @@ lpfc_issue_els_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        struct lpfc_hba  *phba = vport->phba;
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
-       struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        int rc;
 
-       psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];
-
        spin_lock_irq(shost->host_lock);
        if (ndlp->nlp_flag & NLP_LOGO_SND) {
                spin_unlock_irq(shost->host_lock);
@@ -1492,7 +2090,7 @@ lpfc_issue_els_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        spin_lock_irq(shost->host_lock);
        ndlp->nlp_flag |= NLP_LOGO_SND;
        spin_unlock_irq(shost->host_lock);
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
 
        if (rc == IOCB_ERROR) {
                spin_lock_irq(shost->host_lock);
@@ -1504,6 +2102,22 @@ lpfc_issue_els_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        return 0;
 }
 
+/**
+ * lpfc_cmpl_els_cmd - Completion callback function for generic els command
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is a generic completion callback function for ELS commands.
+ * Specifically, it is the callback function which does not need to perform
+ * any command specific operations. It is currently used by the ELS command
+ * issuing routines for the ELS State Change  Request (SCR),
+ * lpfc_issue_els_scr(), and the ELS Fibre Channel Address Resolution
+ * Protocol Response (FARPR) routine, lpfc_issue_els_farpr(). Other than
+ * certain debug loggings, this callback function simply invokes the
+ * lpfc_els_chk_latt() routine to check whether link went down during the
+ * discovery process.
+ **/
 static void
 lpfc_cmpl_els_cmd(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_iocbq *rspiocb)
@@ -1528,31 +2142,62 @@ lpfc_cmpl_els_cmd(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        return;
 }
 
+/**
+ * lpfc_issue_els_scr - Issue a scr to an node on a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @nportid: N_Port identifier to the remote node.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues a State Change Request (SCR) to a fabric node
+ * on a @vport. The remote node @nportid is passed into the function. It
+ * first search the @vport node list to find the matching ndlp. If no such
+ * ndlp is found, a new ndlp shall be created for this (SCR) purpose. An
+ * IOCB is allocated, payload prepared, and the lpfc_sli_issue_iocb()
+ * routine is invoked to send the SCR IOCB.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the SCR ELS command.
+ *
+ * Return code
+ *   0 - Successfully issued scr command
+ *   1 - Failed to issue scr command
+ **/
 int
 lpfc_issue_els_scr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
 {
        struct lpfc_hba  *phba = vport->phba;
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        struct lpfc_nodelist *ndlp;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
        cmdsize = (sizeof(uint32_t) + sizeof(SCR));
-       ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
-       if (!ndlp)
-               return 1;
 
-       lpfc_nlp_init(vport, ndlp, nportid);
+       ndlp = lpfc_findnode_did(vport, nportid);
+       if (!ndlp) {
+               ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
+               if (!ndlp)
+                       return 1;
+               lpfc_nlp_init(vport, ndlp, nportid);
+               lpfc_enqueue_node(vport, ndlp);
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               ndlp = lpfc_enable_node(vport, ndlp, NLP_STE_UNUSED_NODE);
+               if (!ndlp)
+                       return 1;
+       }
 
        elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp,
                                     ndlp->nlp_DID, ELS_CMD_SCR);
 
        if (!elsiocb) {
+               /* This will trigger the release of the node just
+                * allocated
+                */
                lpfc_nlp_put(ndlp);
                return 1;
        }
@@ -1573,22 +2218,51 @@ lpfc_issue_els_scr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
 
        phba->fc_stat.elsXmitSCR++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_cmd;
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
+               /* The additional lpfc_nlp_put will cause the following
+                * lpfc_els_free_iocb routine to trigger the rlease of
+                * the node.
+                */
                lpfc_nlp_put(ndlp);
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
        }
+       /* This will cause the callback-function lpfc_cmpl_els_cmd to
+        * trigger the release of node.
+        */
        lpfc_nlp_put(ndlp);
        return 0;
 }
 
+/**
+ * lpfc_issue_els_farpr - Issue a farp to an node on a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @nportid: N_Port identifier to the remote node.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine issues a Fibre Channel Address Resolution Response
+ * (FARPR) to a node on a vport. The remote node N_Port identifier (@nportid)
+ * is passed into the function. It first search the @vport node list to find
+ * the matching ndlp. If no such ndlp is found, a new ndlp shall be created
+ * for this (FARPR) purpose. An IOCB is allocated, payload prepared, and the
+ * lpfc_sli_issue_iocb() routine is invoked to send the FARPR ELS command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the PARPR ELS command.
+ *
+ * Return code
+ *   0 - Successfully issued farpr command
+ *   1 - Failed to issue farpr command
+ **/
 static int
 lpfc_issue_els_farpr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
 {
        struct lpfc_hba  *phba = vport->phba;
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        FARP *fp;
        uint8_t *pcmd;
@@ -1598,17 +2272,27 @@ lpfc_issue_els_farpr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
        struct lpfc_nodelist *ndlp;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
        cmdsize = (sizeof(uint32_t) + sizeof(FARP));
-       ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
-       if (!ndlp)
-               return 1;
 
-       lpfc_nlp_init(vport, ndlp, nportid);
+       ndlp = lpfc_findnode_did(vport, nportid);
+       if (!ndlp) {
+               ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
+               if (!ndlp)
+                       return 1;
+               lpfc_nlp_init(vport, ndlp, nportid);
+               lpfc_enqueue_node(vport, ndlp);
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               ndlp = lpfc_enable_node(vport, ndlp, NLP_STE_UNUSED_NODE);
+               if (!ndlp)
+                       return 1;
+       }
 
        elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp,
                                     ndlp->nlp_DID, ELS_CMD_RNID);
        if (!elsiocb) {
+               /* This will trigger the release of the node just
+                * allocated
+                */
                lpfc_nlp_put(ndlp);
                return 1;
        }
@@ -1631,7 +2315,7 @@ lpfc_issue_els_farpr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
        memcpy(&fp->RportName, &vport->fc_portname, sizeof(struct lpfc_name));
        memcpy(&fp->RnodeName, &vport->fc_nodename, sizeof(struct lpfc_name));
        ondlp = lpfc_findnode_did(vport, nportid);
-       if (ondlp) {
+       if (ondlp && NLP_CHK_NODE_ACT(ondlp)) {
                memcpy(&fp->OportName, &ondlp->nlp_portname,
                       sizeof(struct lpfc_name));
                memcpy(&fp->OnodeName, &ondlp->nlp_nodename,
@@ -1644,51 +2328,92 @@ lpfc_issue_els_farpr(struct lpfc_vport *vport, uint32_t nportid, uint8_t retry)
 
        phba->fc_stat.elsXmitFARPR++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_cmd;
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
+               /* The additional lpfc_nlp_put will cause the following
+                * lpfc_els_free_iocb routine to trigger the release of
+                * the node.
+                */
                lpfc_nlp_put(ndlp);
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
        }
+       /* This will cause the callback-function lpfc_cmpl_els_cmd to
+        * trigger the release of the node.
+        */
        lpfc_nlp_put(ndlp);
        return 0;
 }
 
+/**
+ * lpfc_cancel_retry_delay_tmo - Cancel the timer with delayed iocb-cmd retry
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @nlp: pointer to a node-list data structure.
+ *
+ * This routine cancels the timer with a delayed IOCB-command retry for
+ * a @vport's @ndlp. It stops the timer for the delayed function retrial and
+ * removes the ELS retry event if it presents. In addition, if the
+ * NLP_NPR_2B_DISC bit is set in the @nlp's nlp_flag bitmap, ADISC IOCB
+ * commands are sent for the @vport's nodes that require issuing discovery
+ * ADISC.
+ **/
 void
 lpfc_cancel_retry_delay_tmo(struct lpfc_vport *vport, struct lpfc_nodelist *nlp)
 {
        struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
+       struct lpfc_work_evt *evtp;
 
+       if (!(nlp->nlp_flag & NLP_DELAY_TMO))
+               return;
        spin_lock_irq(shost->host_lock);
        nlp->nlp_flag &= ~NLP_DELAY_TMO;
        spin_unlock_irq(shost->host_lock);
        del_timer_sync(&nlp->nlp_delayfunc);
        nlp->nlp_last_elscmd = 0;
-
-       if (!list_empty(&nlp->els_retry_evt.evt_listp))
+       if (!list_empty(&nlp->els_retry_evt.evt_listp)) {
                list_del_init(&nlp->els_retry_evt.evt_listp);
-
+               /* Decrement nlp reference count held for the delayed retry */
+               evtp = &nlp->els_retry_evt;
+               lpfc_nlp_put((struct lpfc_nodelist *)evtp->evt_arg1);
+       }
        if (nlp->nlp_flag & NLP_NPR_2B_DISC) {
                spin_lock_irq(shost->host_lock);
                nlp->nlp_flag &= ~NLP_NPR_2B_DISC;
                spin_unlock_irq(shost->host_lock);
                if (vport->num_disc_nodes) {
-                       /* Check to see if there are more
-                        * PLOGIs to be sent
-                        */
-                       lpfc_more_plogi(vport);
-
-                       if (vport->num_disc_nodes == 0) {
-                               spin_lock_irq(shost->host_lock);
-                               vport->fc_flag &= ~FC_NDISC_ACTIVE;
-                               spin_unlock_irq(shost->host_lock);
-                               lpfc_can_disctmo(vport);
-                               lpfc_end_rscn(vport);
+                       if (vport->port_state < LPFC_VPORT_READY) {
+                               /* Check if there are more ADISCs to be sent */
+                               lpfc_more_adisc(vport);
+                       } else {
+                               /* Check if there are more PLOGIs to be sent */
+                               lpfc_more_plogi(vport);
+                               if (vport->num_disc_nodes == 0) {
+                                       spin_lock_irq(shost->host_lock);
+                                       vport->fc_flag &= ~FC_NDISC_ACTIVE;
+                                       spin_unlock_irq(shost->host_lock);
+                                       lpfc_can_disctmo(vport);
+                                       lpfc_end_rscn(vport);
+                               }
                        }
                }
        }
        return;
 }
 
+/**
+ * lpfc_els_retry_delay - Timer function with a ndlp delayed function timer
+ * @ptr: holder for the pointer to the timer function associated data (ndlp).
+ *
+ * This routine is invoked by the ndlp delayed-function timer to check
+ * whether there is any pending ELS retry event(s) with the node. If not, it
+ * simply returns. Otherwise, if there is at least one ELS delayed event, it
+ * adds the delayed events to the HBA work list and invokes the
+ * lpfc_worker_wake_up() routine to wake up worker thread to process the
+ * event. Note that lpfc_nlp_get() is called before posting the event to
+ * the work list to hold reference count of ndlp so that it guarantees the
+ * reference to ndlp will still be available when the worker thread gets
+ * to the event associated with the ndlp.
+ **/
 void
 lpfc_els_retry_delay(unsigned long ptr)
 {
@@ -1698,26 +2423,34 @@ lpfc_els_retry_delay(unsigned long ptr)
        unsigned long flags;
        struct lpfc_work_evt  *evtp = &ndlp->els_retry_evt;
 
-       ndlp = (struct lpfc_nodelist *) ptr;
-       phba = ndlp->vport->phba;
-       evtp = &ndlp->els_retry_evt;
-
        spin_lock_irqsave(&phba->hbalock, flags);
        if (!list_empty(&evtp->evt_listp)) {
                spin_unlock_irqrestore(&phba->hbalock, flags);
                return;
        }
 
-       evtp->evt_arg1  = ndlp;
-       evtp->evt       = LPFC_EVT_ELS_RETRY;
-       list_add_tail(&evtp->evt_listp, &phba->work_list);
-       if (phba->work_wait)
+       /* We need to hold the node by incrementing the reference
+        * count until the queued work is done
+        */
+       evtp->evt_arg1  = lpfc_nlp_get(ndlp);
+       if (evtp->evt_arg1) {
+               evtp->evt = LPFC_EVT_ELS_RETRY;
+               list_add_tail(&evtp->evt_listp, &phba->work_list);
                lpfc_worker_wake_up(phba);
-
+       }
        spin_unlock_irqrestore(&phba->hbalock, flags);
        return;
 }
 
+/**
+ * lpfc_els_retry_delay_handler - Work thread handler for ndlp delayed function
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine is the worker-thread handler for processing the @ndlp delayed
+ * event(s), posted by the lpfc_els_retry_delay() routine. It simply retrieves
+ * the last ELS command from the associated ndlp and invokes the proper ELS
+ * function according to the delayed ELS command to retry the command.
+ **/
 void
 lpfc_els_retry_delay_handler(struct lpfc_nodelist *ndlp)
 {
@@ -1744,6 +2477,7 @@ lpfc_els_retry_delay_handler(struct lpfc_nodelist *ndlp)
         */
        del_timer_sync(&ndlp->nlp_delayfunc);
        retry = ndlp->nlp_retry;
+       ndlp->nlp_retry = 0;
 
        switch (cmd) {
        case ELS_CMD_FLOGI:
@@ -1780,6 +2514,27 @@ lpfc_els_retry_delay_handler(struct lpfc_nodelist *ndlp)
        return;
 }
 
+/**
+ * lpfc_els_retry - Make retry decision on an els command iocb
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine makes a retry decision on an ELS command IOCB, which has
+ * failed. The following ELS IOCBs use this function for retrying the command
+ * when previously issued command responsed with error status: FLOGI, PLOGI,
+ * PRLI, ADISC, LOGO, and FDISC. Based on the ELS command type and the
+ * returned error status, it makes the decision whether a retry shall be
+ * issued for the command, and whether a retry shall be made immediately or
+ * delayed. In the former case, the corresponding ELS command issuing-function
+ * is called to retry the command. In the later case, the ELS command shall
+ * be posted to the ndlp delayed event and delayed function timer set to the
+ * ndlp for the delayed command issusing.
+ *
+ * Return code
+ *   0 - No retry of els command is made
+ *   1 - Immediate or delayed retry of els command is made
+ **/
 static int
 lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
               struct lpfc_iocbq *rspiocb)
@@ -1806,13 +2561,14 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                cmd = *elscmd++;
        }
 
-       if (ndlp)
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp))
                did = ndlp->nlp_DID;
        else {
                /* We should only hit this case for retrying PLOGI */
                did = irsp->un.elsreq64.remoteID;
                ndlp = lpfc_findnode_did(vport, did);
-               if (!ndlp && (cmd != ELS_CMD_PLOGI))
+               if ((!ndlp || !NLP_CHK_NODE_ACT(ndlp))
+                   && (cmd != ELS_CMD_PLOGI))
                        return 1;
        }
 
@@ -1828,24 +2584,30 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        case IOSTAT_LOCAL_REJECT:
                switch ((irsp->un.ulpWord[4] & 0xff)) {
                case IOERR_LOOP_OPEN_FAILURE:
+                       if (cmd == ELS_CMD_FLOGI) {
+                               if (PCI_DEVICE_ID_HORNET ==
+                                       phba->pcidev->device) {
+                                       phba->fc_topology = TOPOLOGY_LOOP;
+                                       phba->pport->fc_myDID = 0;
+                                       phba->alpa_map[0] = 0;
+                                       phba->alpa_map[1] = 0;
+                               }
+                       }
                        if (cmd == ELS_CMD_PLOGI && cmdiocb->retry == 0)
                                delay = 1000;
                        retry = 1;
                        break;
 
                case IOERR_ILLEGAL_COMMAND:
-                       if ((phba->sli3_options & LPFC_SLI3_VPORT_TEARDOWN) &&
-                           (cmd == ELS_CMD_FDISC)) {
-                               lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
-                                                "0124 FDISC failed (3/6) "
-                                                "retrying...\n");
-                               lpfc_mbx_unreg_vpi(vport);
-                               retry = 1;
-                               /* FDISC retry policy */
-                               maxretry = 48;
-                               if (cmdiocb->retry >= 32)
-                                       delay = 1000;
-                       }
+                       lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                                        "0124 Retry illegal cmd x%x "
+                                        "retry:x%x delay:x%x\n",
+                                        cmd, cmdiocb->retry, delay);
+                       retry = 1;
+                       /* All command's retry policy */
+                       maxretry = 8;
+                       if (cmdiocb->retry > 2)
+                               delay = 1000;
                        break;
 
                case IOERR_NO_RESOURCES:
@@ -1931,6 +2693,17 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                        break;
 
                case LSRJT_LOGICAL_ERR:
+                       /* There are some cases where switches return this
+                        * error when they are not ready and should be returning
+                        * Logical Busy. We should delay every time.
+                        */
+                       if (cmd == ELS_CMD_FDISC &&
+                           stat.un.b.lsRjtRsnCodeExp == LSEXP_PORT_LOGIN_REQ) {
+                               maxretry = 3;
+                               delay = 1000;
+                               retry = 1;
+                               break;
+                       }
                case LSRJT_PROTOCOL_ERR:
                        if ((phba->sli3_options & LPFC_SLI3_NPIV_ENABLED) &&
                          (cmd == ELS_CMD_FDISC) &&
@@ -1938,7 +2711,7 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                          (stat.un.b.lsRjtRsnCodeExp == LSEXP_INVALID_NPORT_ID))
                          ) {
                                lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
-                                                "0123 FDISC Failed (x%x). "
+                                                "0122 FDISC Failed (x%x). "
                                                 "Fabric Detected Bad WWN\n",
                                                 stat.un.lsRjtError);
                                lpfc_vport_set_state(vport,
@@ -1959,16 +2732,21 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        if (did == FDMI_DID)
                retry = 1;
 
-       if ((cmd == ELS_CMD_FLOGI) &&
-           (phba->fc_topology != TOPOLOGY_LOOP)) {
+       if (((cmd == ELS_CMD_FLOGI) || (cmd == ELS_CMD_FDISC)) &&
+           (phba->fc_topology != TOPOLOGY_LOOP) &&
+           !lpfc_error_lost_link(irsp)) {
                /* FLOGI retry policy */
                retry = 1;
-               maxretry = 48;
-               if (cmdiocb->retry >= 32)
+               /* retry forever */
+               maxretry = 0;
+               if (cmdiocb->retry >= 100)
+                       delay = 5000;
+               else if (cmdiocb->retry >= 32)
                        delay = 1000;
        }
 
-       if ((++cmdiocb->retry) >= maxretry) {
+       cmdiocb->retry++;
+       if (maxretry && (cmdiocb->retry >= maxretry)) {
                phba->fc_stat.elsRetryExceeded++;
                retry = 0;
        }
@@ -1996,7 +2774,7 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                }
 
                phba->fc_stat.elsXmitRetry++;
-               if (ndlp && delay) {
+               if (ndlp && NLP_CHK_NODE_ACT(ndlp) && delay) {
                        phba->fc_stat.elsDelayRetry++;
                        ndlp->nlp_retry = cmdiocb->retry;
 
@@ -2026,7 +2804,7 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                        lpfc_issue_els_fdisc(vport, ndlp, cmdiocb->retry);
                        return 1;
                case ELS_CMD_PLOGI:
-                       if (ndlp) {
+                       if (ndlp && NLP_CHK_NODE_ACT(ndlp)) {
                                ndlp->nlp_prev_state = ndlp->nlp_state;
                                lpfc_nlp_set_state(vport, ndlp,
                                                   NLP_STE_PLOGI_ISSUE);
@@ -2068,12 +2846,26 @@ lpfc_els_retry(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
-int
+/**
+ * lpfc_els_free_data - Free lpfc dma buffer and data structure with an iocb
+ * @phba: pointer to lpfc hba data structure.
+ * @buf_ptr1: pointer to the lpfc DMA buffer data structure.
+ *
+ * This routine releases the lpfc DMA (Direct Memory Access) buffer(s)
+ * associated with a command IOCB back to the lpfc DMA buffer pool. It first
+ * checks to see whether there is a lpfc DMA buffer associated with the
+ * response of the command IOCB. If so, it will be released before releasing
+ * the lpfc DMA buffer associated with the IOCB itself.
+ *
+ * Return code
+ *   0 - Successfully released lpfc DMA buffer (currently, always return 0)
+ **/
+static int
 lpfc_els_free_data(struct lpfc_hba *phba, struct lpfc_dmabuf *buf_ptr1)
 {
        struct lpfc_dmabuf *buf_ptr;
 
-       /* Free the response before processing the command.  */
+       /* Free the response before processing the command. */
        if (!list_empty(&buf_ptr1->list)) {
                list_remove_head(&buf_ptr1->list, buf_ptr,
                                 struct lpfc_dmabuf,
@@ -2086,7 +2878,19 @@ lpfc_els_free_data(struct lpfc_hba *phba, struct lpfc_dmabuf *buf_ptr1)
        return 0;
 }
 
-int
+/**
+ * lpfc_els_free_bpl - Free lpfc dma buffer and data structure with bpl
+ * @phba: pointer to lpfc hba data structure.
+ * @buf_ptr: pointer to the lpfc dma buffer data structure.
+ *
+ * This routine releases the lpfc Direct Memory Access (DMA) buffer
+ * associated with a Buffer Pointer List (BPL) back to the lpfc DMA buffer
+ * pool.
+ *
+ * Return code
+ *   0 - Successfully released lpfc DMA buffer (currently, always return 0)
+ **/
+static int
 lpfc_els_free_bpl(struct lpfc_hba *phba, struct lpfc_dmabuf *buf_ptr)
 {
        lpfc_mbuf_free(phba, buf_ptr->virt, buf_ptr->phys);
@@ -2094,6 +2898,33 @@ lpfc_els_free_bpl(struct lpfc_hba *phba, struct lpfc_dmabuf *buf_ptr)
        return 0;
 }
 
+/**
+ * lpfc_els_free_iocb - Free a command iocb and its associated resources
+ * @phba: pointer to lpfc hba data structure.
+ * @elsiocb: pointer to lpfc els command iocb data structure.
+ *
+ * This routine frees a command IOCB and its associated resources. The
+ * command IOCB data structure contains the reference to various associated
+ * resources, these fields must be set to NULL if the associated reference
+ * not present:
+ *   context1 - reference to ndlp
+ *   context2 - reference to cmd
+ *   context2->next - reference to rsp
+ *   context3 - reference to bpl
+ *
+ * It first properly decrements the reference count held on ndlp for the
+ * IOCB completion callback function. If LPFC_DELAY_MEM_FREE flag is not
+ * set, it invokes the lpfc_els_free_data() routine to release the Direct
+ * Memory Access (DMA) buffers associated with the IOCB. Otherwise, it
+ * adds the DMA buffer the @phba data structure for the delayed release.
+ * If reference to the Buffer Pointer List (BPL) is present, the
+ * lpfc_els_free_bpl() routine is invoked to release the DMA memory
+ * associated with BPL. Finally, the lpfc_sli_release_iocbq() routine is
+ * invoked to release the IOCB data structure back to @phba IOCBQ list.
+ *
+ * Return code
+ *   0 - Success (currently, always return 0)
+ **/
 int
 lpfc_els_free_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *elsiocb)
 {
@@ -2160,6 +2991,23 @@ lpfc_els_free_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *elsiocb)
        return 0;
 }
 
+/**
+ * lpfc_cmpl_els_logo_acc - Completion callback function to logo acc response
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function to the Logout (LOGO)
+ * Accept (ACC) Response ELS command. This routine is invoked to indicate
+ * the completion of the LOGO process. It invokes the lpfc_nlp_not_used() to
+ * release the ndlp if it has the last reference remaining (reference count
+ * is 1). If succeeded (meaning ndlp released), it sets the IOCB context1
+ * field to NULL to inform the following lpfc_els_free_iocb() routine no
+ * ndlp reference count needs to be decremented. Otherwise, the ndlp
+ * reference use-count shall be decremented by the lpfc_els_free_iocb()
+ * routine. Finally, the lpfc_els_free_iocb() is invoked to release the
+ * IOCB data structure.
+ **/
 static void
 lpfc_cmpl_els_logo_acc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                       struct lpfc_iocbq *rspiocb)
@@ -2186,34 +3034,76 @@ lpfc_cmpl_els_logo_acc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                         * thread, just unregister the RPI.
                         */
                        lpfc_unreg_rpi(vport, ndlp);
+               } else {
+                       /* Indicate the node has already released, should
+                        * not reference to it from within lpfc_els_free_iocb.
+                        */
+                       cmdiocb->context1 = NULL;
                }
        }
        lpfc_els_free_iocb(phba, cmdiocb);
        return;
 }
 
+/**
+ * lpfc_mbx_cmpl_dflt_rpi - Completion callbk func for unreg dflt rpi mbox cmd
+ * @phba: pointer to lpfc hba data structure.
+ * @pmb: pointer to the driver internal queue element for mailbox command.
+ *
+ * This routine is the completion callback function for unregister default
+ * RPI (Remote Port Index) mailbox command to the @phba. It simply releases
+ * the associated lpfc Direct Memory Access (DMA) buffer back to the pool and
+ * decrements the ndlp reference count held for this completion callback
+ * function. After that, it invokes the lpfc_nlp_not_used() to check
+ * whether there is only one reference left on the ndlp. If so, it will
+ * perform one more decrement and trigger the release of the ndlp.
+ **/
 void
 lpfc_mbx_cmpl_dflt_rpi(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 {
        struct lpfc_dmabuf *mp = (struct lpfc_dmabuf *) (pmb->context1);
        struct lpfc_nodelist *ndlp = (struct lpfc_nodelist *) pmb->context2;
 
+       /*
+        * This routine is used to register and unregister in previous SLI
+        * modes.
+        */
+       if ((pmb->u.mb.mbxCommand == MBX_UNREG_LOGIN) &&
+           (phba->sli_rev == LPFC_SLI_REV4))
+               lpfc_sli4_free_rpi(phba, pmb->u.mb.un.varUnregLogin.rpi);
+
        pmb->context1 = NULL;
        lpfc_mbuf_free(phba, mp->virt, mp->phys);
        kfree(mp);
        mempool_free(pmb, phba->mbox_mem_pool);
-       if (ndlp) {
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp)) {
                lpfc_nlp_put(ndlp);
-
                /* This is the end of the default RPI cleanup logic for this
                 * ndlp. If no other discovery threads are using this ndlp.
                 * we should free all resources associated with it.
                 */
                lpfc_nlp_not_used(ndlp);
        }
+
        return;
 }
 
+/**
+ * lpfc_cmpl_els_rsp - Completion callback function for els response iocb cmd
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function for ELS Response IOCB
+ * command. In normal case, this callback function just properly sets the
+ * nlp_flag bitmap in the ndlp data structure, if the mbox command reference
+ * field in the command IOCB is not NULL, the referred mailbox command will
+ * be send out, and then invokes the lpfc_els_free_iocb() routine to release
+ * the IOCB. Under error conditions, such as when a LS_RJT is returned or a
+ * link down event occurred during the discovery, the lpfc_nlp_not_used()
+ * routine shall be invoked trying to release the ndlp if no other threads
+ * are currently referring it.
+ **/
 static void
 lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_iocbq *rspiocb)
@@ -2232,18 +3122,21 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        if (cmdiocb->context_un.mbox)
                mbox = cmdiocb->context_un.mbox;
 
-       /* First determine if this is a LS_RJT cmpl */
+       /* First determine if this is a LS_RJT cmpl. Note, this callback
+        * function can have cmdiocb->contest1 (ndlp) field set to NULL.
+        */
        pcmd = (uint8_t *) (((struct lpfc_dmabuf *) cmdiocb->context2)->virt);
-       if (*((uint32_t *) (pcmd)) == ELS_CMD_LS_RJT) {
-               /* A LS_RJT associated with Default RPI cleanup
-                * has its own seperate code path.
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp) &&
+           (*((uint32_t *) (pcmd)) == ELS_CMD_LS_RJT)) {
+               /* A LS_RJT associated with Default RPI cleanup has its own
+                * separate code path.
                 */
                if (!(ndlp->nlp_flag & NLP_RM_DFLT_RPI))
                        ls_rjt = 1;
        }
 
        /* Check to see if link went down during discovery */
-       if (!ndlp || lpfc_els_chk_latt(vport)) {
+       if (!ndlp || !NLP_CHK_NODE_ACT(ndlp) || lpfc_els_chk_latt(vport)) {
                if (mbox) {
                        mp = (struct lpfc_dmabuf *) mbox->context1;
                        if (mp) {
@@ -2252,9 +3145,16 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                        }
                        mempool_free(mbox, phba->mbox_mem_pool);
                }
-               if (ndlp && (ndlp->nlp_flag & NLP_RM_DFLT_RPI))
-                       if (lpfc_nlp_not_used(ndlp))
+               if (ndlp && NLP_CHK_NODE_ACT(ndlp) &&
+                   (ndlp->nlp_flag & NLP_RM_DFLT_RPI))
+                       if (lpfc_nlp_not_used(ndlp)) {
                                ndlp = NULL;
+                               /* Indicate the node has already released,
+                                * should not reference to it from within
+                                * the routine lpfc_els_free_iocb.
+                                */
+                               cmdiocb->context1 = NULL;
+                       }
                goto out;
        }
 
@@ -2274,6 +3174,9 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                if ((rspiocb->iocb.ulpStatus == 0)
                    && (ndlp->nlp_flag & NLP_ACC_REGLOGIN)) {
                        lpfc_unreg_rpi(vport, ndlp);
+                       /* Increment reference count to ndlp to hold the
+                        * reference to ndlp for the callback function.
+                        */
                        mbox->context2 = lpfc_nlp_get(ndlp);
                        mbox->vport = vport;
                        if (ndlp->nlp_flag & NLP_RM_DFLT_RPI) {
@@ -2287,9 +3190,13 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                                           NLP_STE_REG_LOGIN_ISSUE);
                        }
                        if (lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT)
-                           != MBX_NOT_FINISHED) {
+                           != MBX_NOT_FINISHED)
                                goto out;
-                       }
+                       else
+                               /* Decrement the ndlp reference count we
+                                * set for this failed mailbox command.
+                                */
+                               lpfc_nlp_put(ndlp);
 
                        /* ELS rsp: Cannot issue reg_login for <NPortid> */
                        lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
@@ -2298,14 +3205,27 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                                ndlp->nlp_DID, ndlp->nlp_flag, ndlp->nlp_state,
                                ndlp->nlp_rpi);
 
-                       if (lpfc_nlp_not_used(ndlp))
+                       if (lpfc_nlp_not_used(ndlp)) {
                                ndlp = NULL;
+                               /* Indicate node has already been released,
+                                * should not reference to it from within
+                                * the routine lpfc_els_free_iocb.
+                                */
+                               cmdiocb->context1 = NULL;
+                       }
                } else {
                        /* Do not drop node for lpfc_els_abort'ed ELS cmds */
                        if (!lpfc_error_lost_link(irsp) &&
                            ndlp->nlp_flag & NLP_ACC_REGLOGIN) {
-                               if (lpfc_nlp_not_used(ndlp))
+                               if (lpfc_nlp_not_used(ndlp)) {
                                        ndlp = NULL;
+                                       /* Indicate node has already been
+                                        * released, should not reference
+                                        * to it from within the routine
+                                        * lpfc_els_free_iocb.
+                                        */
+                                       cmdiocb->context1 = NULL;
+                               }
                        }
                }
                mp = (struct lpfc_dmabuf *) mbox->context1;
@@ -2316,7 +3236,7 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                mempool_free(mbox, phba->mbox_mem_pool);
        }
 out:
-       if (ndlp) {
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp)) {
                spin_lock_irq(shost->host_lock);
                ndlp->nlp_flag &= ~(NLP_ACC_REGLOGIN | NLP_RM_DFLT_RPI);
                spin_unlock_irq(shost->host_lock);
@@ -2327,13 +3247,43 @@ out:
                 * resources.
                 */
                if (ls_rjt)
-                       lpfc_nlp_not_used(ndlp);
+                       if (lpfc_nlp_not_used(ndlp))
+                               /* Indicate node has already been released,
+                                * should not reference to it from within
+                                * the routine lpfc_els_free_iocb.
+                                */
+                               cmdiocb->context1 = NULL;
        }
 
        lpfc_els_free_iocb(phba, cmdiocb);
        return;
 }
 
+/**
+ * lpfc_els_rsp_acc - Prepare and issue an acc response iocb command
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @flag: the els command code to be accepted.
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @mbox: pointer to the driver internal queue element for mailbox command.
+ *
+ * This routine prepares and issues an Accept (ACC) response IOCB
+ * command. It uses the @flag to properly set up the IOCB field for the
+ * specific ACC response command to be issued and invokes the
+ * lpfc_sli_issue_iocb() routine to send out ACC response IOCB. If a
+ * @mbox pointer is passed in, it will be put into the context_un.mbox
+ * field of the IOCB for the completion callback function to issue the
+ * mailbox command to the HBA later when callback is invoked.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the corresponding response ELS IOCB command.
+ *
+ * Return code
+ *   0 - Successfully issued acc response
+ *   1 - Failed to issue acc response
+ **/
 int
 lpfc_els_rsp_acc(struct lpfc_vport *vport, uint32_t flag,
                 struct lpfc_iocbq *oldiocb, struct lpfc_nodelist *ndlp,
@@ -2344,7 +3294,6 @@ lpfc_els_rsp_acc(struct lpfc_vport *vport, uint32_t flag,
        IOCB_t *icmd;
        IOCB_t *oldcmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
@@ -2352,7 +3301,6 @@ lpfc_els_rsp_acc(struct lpfc_vport *vport, uint32_t flag,
        ELS_PKT *els_pkt_ptr;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
        oldcmd = &oldiocb->iocb;
 
        switch (flag) {
@@ -2440,7 +3388,7 @@ lpfc_els_rsp_acc(struct lpfc_vport *vport, uint32_t flag,
        }
 
        phba->fc_stat.elsXmitACC++;
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
        if (rc == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
@@ -2448,6 +3396,28 @@ lpfc_els_rsp_acc(struct lpfc_vport *vport, uint32_t flag,
        return 0;
 }
 
+/**
+ * lpfc_els_rsp_reject - Propare and issue a rjt response iocb command
+ * @vport: pointer to a virtual N_Port data structure.
+ * @rejectError:
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @mbox: pointer to the driver internal queue element for mailbox command.
+ *
+ * This routine prepares and issue an Reject (RJT) response IOCB
+ * command. If a @mbox pointer is passed in, it will be put into the
+ * context_un.mbox field of the IOCB for the completion callback function
+ * to issue to the HBA later.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the reject response ELS IOCB command.
+ *
+ * Return code
+ *   0 - Successfully issued reject response
+ *   1 - Failed to issue reject response
+ **/
 int
 lpfc_els_rsp_reject(struct lpfc_vport *vport, uint32_t rejectError,
                    struct lpfc_iocbq *oldiocb, struct lpfc_nodelist *ndlp,
@@ -2457,15 +3427,12 @@ lpfc_els_rsp_reject(struct lpfc_vport *vport, uint32_t rejectError,
        IOCB_t *icmd;
        IOCB_t *oldcmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        int rc;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
-
        cmdsize = 2 * sizeof(uint32_t);
        elsiocb = lpfc_prep_els_iocb(vport, 0, cmdsize, oldiocb->retry, ndlp,
                                     ndlp->nlp_DID, ELS_CMD_LS_RJT);
@@ -2498,7 +3465,7 @@ lpfc_els_rsp_reject(struct lpfc_vport *vport, uint32_t rejectError,
 
        phba->fc_stat.elsXmitLSRJT++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_rsp;
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
 
        if (rc == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
@@ -2507,13 +3474,30 @@ lpfc_els_rsp_reject(struct lpfc_vport *vport, uint32_t rejectError,
        return 0;
 }
 
+/**
+ * lpfc_els_rsp_adisc_acc - Prepare and issue acc response to adisc iocb cmd
+ * @vport: pointer to a virtual N_Port data structure.
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine prepares and issues an Accept (ACC) response to Address
+ * Discover (ADISC) ELS command. It simply prepares the payload of the IOCB
+ * and invokes the lpfc_sli_issue_iocb() routine to send out the command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the ADISC Accept response ELS IOCB command.
+ *
+ * Return code
+ *   0 - Successfully issued acc adisc response
+ *   1 - Failed to issue adisc acc response
+ **/
 int
 lpfc_els_rsp_adisc_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
                       struct lpfc_nodelist *ndlp)
 {
        struct lpfc_hba  *phba = vport->phba;
-       struct lpfc_sli  *psli = &phba->sli;
-       struct lpfc_sli_ring *pring = &psli->ring[LPFC_ELS_RING];
        ADISC *ap;
        IOCB_t *icmd, *oldcmd;
        struct lpfc_iocbq *elsiocb;
@@ -2555,7 +3539,7 @@ lpfc_els_rsp_adisc_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
 
        phba->fc_stat.elsXmitACC++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_rsp;
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
        if (rc == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
@@ -2563,6 +3547,25 @@ lpfc_els_rsp_adisc_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rsp_prli_acc - Prepare and issue acc response to prli iocb cmd
+ * @vport: pointer to a virtual N_Port data structure.
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine prepares and issues an Accept (ACC) response to Process
+ * Login (PRLI) ELS command. It simply prepares the payload of the IOCB
+ * and invokes the lpfc_sli_issue_iocb() routine to send out the command.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the PRLI Accept response ELS IOCB command.
+ *
+ * Return code
+ *   0 - Successfully issued acc prli response
+ *   1 - Failed to issue acc prli response
+ **/
 int
 lpfc_els_rsp_prli_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
                      struct lpfc_nodelist *ndlp)
@@ -2573,14 +3576,12 @@ lpfc_els_rsp_prli_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
        IOCB_t *icmd;
        IOCB_t *oldcmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        int rc;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];     /* ELS ring */
 
        cmdsize = sizeof(uint32_t) + sizeof(PRLI);
        elsiocb = lpfc_prep_els_iocb(vport, 0, cmdsize, oldiocb->retry, ndlp,
@@ -2609,10 +3610,11 @@ lpfc_els_rsp_prli_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
        npr = (PRLI *) pcmd;
        vpd = &phba->vpd;
        /*
-        * If our firmware version is 3.20 or later,
-        * set the following bits for FC-TAPE support.
+        * If the remote port is a target and our firmware version is 3.20 or
+        * later, set the following bits for FC-TAPE support.
         */
-       if (vpd->rev.feaLevelHigh >= 0x02) {
+       if ((ndlp->nlp_type & NLP_FCP_TARGET) &&
+           (vpd->rev.feaLevelHigh >= 0x02)) {
                npr->ConfmComplAllowed = 1;
                npr->Retry = 1;
                npr->TaskRetryIdReq = 1;
@@ -2633,7 +3635,7 @@ lpfc_els_rsp_prli_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
        phba->fc_stat.elsXmitACC++;
        elsiocb->iocb_cmpl = lpfc_cmpl_els_rsp;
 
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
        if (rc == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
@@ -2641,6 +3643,32 @@ lpfc_els_rsp_prli_acc(struct lpfc_vport *vport, struct lpfc_iocbq *oldiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rsp_rnid_acc - Issue rnid acc response iocb command
+ * @vport: pointer to a virtual N_Port data structure.
+ * @format: rnid command format.
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine issues a Request Node Identification Data (RNID) Accept
+ * (ACC) response. It constructs the RNID ACC response command according to
+ * the proper @format and then calls the lpfc_sli_issue_iocb() routine to
+ * issue the response. Note that this command does not need to hold the ndlp
+ * reference count for the callback. So, the ndlp reference count taken by
+ * the lpfc_prep_els_iocb() routine is put back and the context1 field of
+ * IOCB is set to NULL to indicate to the lpfc_els_free_iocb() routine that
+ * there is no ndlp reference available.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function. However, for the RNID Accept Response ELS command,
+ * this is undone later by this routine after the IOCB is allocated.
+ *
+ * Return code
+ *   0 - Successfully issued acc rnid response
+ *   1 - Failed to issue acc rnid response
+ **/
 static int
 lpfc_els_rsp_rnid_acc(struct lpfc_vport *vport, uint8_t format,
                      struct lpfc_iocbq *oldiocb, struct lpfc_nodelist *ndlp)
@@ -2649,15 +3677,12 @@ lpfc_els_rsp_rnid_acc(struct lpfc_vport *vport, uint8_t format,
        RNID *rn;
        IOCB_t *icmd, *oldcmd;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli_ring *pring;
        struct lpfc_sli *psli;
        uint8_t *pcmd;
        uint16_t cmdsize;
        int rc;
 
        psli = &phba->sli;
-       pring = &psli->ring[LPFC_ELS_RING];
-
        cmdsize = sizeof(uint32_t) + sizeof(uint32_t)
                                        + (2 * sizeof(struct lpfc_name));
        if (format)
@@ -2713,7 +3738,7 @@ lpfc_els_rsp_rnid_acc(struct lpfc_vport *vport, uint8_t format,
        elsiocb->context1 = NULL;  /* Don't need ndlp for cmpl,
                                    * it could be freed */
 
-       rc = lpfc_sli_issue_iocb(phba, pring, elsiocb, 0);
+       rc = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0);
        if (rc == IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
@@ -2721,6 +3746,25 @@ lpfc_els_rsp_rnid_acc(struct lpfc_vport *vport, uint8_t format,
        return 0;
 }
 
+/**
+ * lpfc_els_disc_adisc - Issue remaining adisc iocbs to npr nodes of a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues Address Discover (ADISC) ELS commands to those
+ * N_Ports which are in node port recovery state and ADISC has not been issued
+ * for the @vport. Each time an ELS ADISC IOCB is issued by invoking the
+ * lpfc_issue_els_adisc() routine, the per @vport number of discover count
+ * (num_disc_nodes) shall be incremented. If the num_disc_nodes reaches a
+ * pre-configured threshold (cfg_discovery_threads), the @vport fc_flag will
+ * be marked with FC_NLP_MORE bit and the process of issuing remaining ADISC
+ * IOCBs quit for later pick up. On the other hand, after walking through
+ * all the ndlps with the @vport and there is none ADISC IOCB issued, the
+ * @vport fc_flag shall be cleared with FC_NLP_MORE bit indicating there is
+ * no more ADISC need to be sent.
+ *
+ * Return code
+ *    The number of N_Ports with adisc issued.
+ **/
 int
 lpfc_els_disc_adisc(struct lpfc_vport *vport)
 {
@@ -2730,6 +3774,8 @@ lpfc_els_disc_adisc(struct lpfc_vport *vport)
 
        /* go thru NPR nodes and issue any remaining ELS ADISCs */
        list_for_each_entry_safe(ndlp, next_ndlp, &vport->fc_nodes, nlp_listp) {
+               if (!NLP_CHK_NODE_ACT(ndlp))
+                       continue;
                if (ndlp->nlp_state == NLP_STE_NPR_NODE &&
                    (ndlp->nlp_flag & NLP_NPR_2B_DISC) != 0 &&
                    (ndlp->nlp_flag & NLP_NPR_ADISC) != 0) {
@@ -2758,6 +3804,25 @@ lpfc_els_disc_adisc(struct lpfc_vport *vport)
        return sentadisc;
 }
 
+/**
+ * lpfc_els_disc_plogi - Issue plogi for all npr nodes of a vport before adisc
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine issues Port Login (PLOGI) ELS commands to all the N_Ports
+ * which are in node port recovery state, with a @vport. Each time an ELS
+ * ADISC PLOGI IOCB is issued by invoking the lpfc_issue_els_plogi() routine,
+ * the per @vport number of discover count (num_disc_nodes) shall be
+ * incremented. If the num_disc_nodes reaches a pre-configured threshold
+ * (cfg_discovery_threads), the @vport fc_flag will be marked with FC_NLP_MORE
+ * bit set and quit the process of issuing remaining ADISC PLOGIN IOCBs for
+ * later pick up. On the other hand, after walking through all the ndlps with
+ * the @vport and there is none ADISC PLOGI IOCB issued, the @vport fc_flag
+ * shall be cleared with the FC_NLP_MORE bit indicating there is no more ADISC
+ * PLOGI need to be sent.
+ *
+ * Return code
+ *   The number of N_Ports with plogi issued.
+ **/
 int
 lpfc_els_disc_plogi(struct lpfc_vport *vport)
 {
@@ -2767,6 +3832,8 @@ lpfc_els_disc_plogi(struct lpfc_vport *vport)
 
        /* go thru NPR nodes and issue any remaining ELS PLOGIs */
        list_for_each_entry_safe(ndlp, next_ndlp, &vport->fc_nodes, nlp_listp) {
+               if (!NLP_CHK_NODE_ACT(ndlp))
+                       continue;
                if (ndlp->nlp_state == NLP_STE_NPR_NODE &&
                    (ndlp->nlp_flag & NLP_NPR_2B_DISC) != 0 &&
                    (ndlp->nlp_flag & NLP_DELAY_TMO) == 0 &&
@@ -2796,6 +3863,15 @@ lpfc_els_disc_plogi(struct lpfc_vport *vport)
        return sentplogi;
 }
 
+/**
+ * lpfc_els_flush_rscn - Clean up any rscn activities with a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine cleans up any Registration State Change Notification
+ * (RSCN) activity with a @vport. Note that the fc_rscn_flush flag of the
+ * @vport together with the host_lock is used to prevent multiple thread
+ * trying to access the RSCN array on a same @vport at the same time.
+ **/
 void
 lpfc_els_flush_rscn(struct lpfc_vport *vport)
 {
@@ -2803,6 +3879,16 @@ lpfc_els_flush_rscn(struct lpfc_vport *vport)
        struct lpfc_hba  *phba = vport->phba;
        int i;
 
+       spin_lock_irq(shost->host_lock);
+       if (vport->fc_rscn_flush) {
+               /* Another thread is walking fc_rscn_id_list on this vport */
+               spin_unlock_irq(shost->host_lock);
+               return;
+       }
+       /* Indicate we are walking lpfc_els_flush_rscn on this vport */
+       vport->fc_rscn_flush = 1;
+       spin_unlock_irq(shost->host_lock);
+
        for (i = 0; i < vport->fc_rscn_id_cnt; i++) {
                lpfc_in_buf_free(phba, vport->fc_rscn_id_list[i]);
                vport->fc_rscn_id_list[i] = NULL;
@@ -2812,8 +3898,22 @@ lpfc_els_flush_rscn(struct lpfc_vport *vport)
        vport->fc_flag &= ~(FC_RSCN_MODE | FC_RSCN_DISCOVERY);
        spin_unlock_irq(shost->host_lock);
        lpfc_can_disctmo(vport);
+       /* Indicate we are done walking this fc_rscn_id_list */
+       vport->fc_rscn_flush = 0;
 }
 
+/**
+ * lpfc_rscn_payload_check - Check whether there is a pending rscn to a did
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @did: remote destination port identifier.
+ *
+ * This routine checks whether there is any pending Registration State
+ * Configuration Notification (RSCN) to a @did on @vport.
+ *
+ * Return code
+ *   None zero - The @did matched with a pending rscn
+ *   0 - not able to match @did with a pending rscn
+ **/
 int
 lpfc_rscn_payload_check(struct lpfc_vport *vport, uint32_t did)
 {
@@ -2821,6 +3921,7 @@ lpfc_rscn_payload_check(struct lpfc_vport *vport, uint32_t did)
        D_ID rscn_did;
        uint32_t *lp;
        uint32_t payload_len, i;
+       struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
 
        ns_did.un.word = did;
 
@@ -2832,6 +3933,15 @@ lpfc_rscn_payload_check(struct lpfc_vport *vport, uint32_t did)
        if (vport->fc_flag & FC_RSCN_DISCOVERY)
                return did;
 
+       spin_lock_irq(shost->host_lock);
+       if (vport->fc_rscn_flush) {
+               /* Another thread is walking fc_rscn_id_list on this vport */
+               spin_unlock_irq(shost->host_lock);
+               return 0;
+       }
+       /* Indicate we are walking fc_rscn_id_list on this vport */
+       vport->fc_rscn_flush = 1;
+       spin_unlock_irq(shost->host_lock);
        for (i = 0; i < vport->fc_rscn_id_cnt; i++) {
                lp = vport->fc_rscn_id_list[i]->virt;
                payload_len = be32_to_cpu(*lp++ & ~ELS_CMD_MASK);
@@ -2839,62 +3949,130 @@ lpfc_rscn_payload_check(struct lpfc_vport *vport, uint32_t did)
                while (payload_len) {
                        rscn_did.un.word = be32_to_cpu(*lp++);
                        payload_len -= sizeof(uint32_t);
-                       switch (rscn_did.un.b.resv) {
-                       case 0: /* Single N_Port ID effected */
-                               if (ns_did.un.word == rscn_did.un.word)
-                                       return did;
+                       switch (rscn_did.un.b.resv & RSCN_ADDRESS_FORMAT_MASK) {
+                       case RSCN_ADDRESS_FORMAT_PORT:
+                               if ((ns_did.un.b.domain == rscn_did.un.b.domain)
+                                   && (ns_did.un.b.area == rscn_did.un.b.area)
+                                   && (ns_did.un.b.id == rscn_did.un.b.id))
+                                       goto return_did_out;
                                break;
-                       case 1: /* Whole N_Port Area effected */
+                       case RSCN_ADDRESS_FORMAT_AREA:
                                if ((ns_did.un.b.domain == rscn_did.un.b.domain)
                                    && (ns_did.un.b.area == rscn_did.un.b.area))
-                                       return did;
+                                       goto return_did_out;
                                break;
-                       case 2: /* Whole N_Port Domain effected */
+                       case RSCN_ADDRESS_FORMAT_DOMAIN:
                                if (ns_did.un.b.domain == rscn_did.un.b.domain)
-                                       return did;
+                                       goto return_did_out;
                                break;
-                       default:
-                               /* Unknown Identifier in RSCN node */
-                               lpfc_printf_vlog(vport, KERN_ERR, LOG_DISCOVERY,
-                                                "0217 Unknown Identifier in "
-                                                "RSCN payload Data: x%x\n",
-                                                rscn_did.un.word);
-                       case 3: /* Whole Fabric effected */
-                               return did;
+                       case RSCN_ADDRESS_FORMAT_FABRIC:
+                               goto return_did_out;
                        }
                }
        }
+       /* Indicate we are done with walking fc_rscn_id_list on this vport */
+       vport->fc_rscn_flush = 0;
        return 0;
+return_did_out:
+       /* Indicate we are done with walking fc_rscn_id_list on this vport */
+       vport->fc_rscn_flush = 0;
+       return did;
 }
 
+/**
+ * lpfc_rscn_recovery_check - Send recovery event to vport nodes matching rscn
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine sends recovery (NLP_EVT_DEVICE_RECOVERY) event to the
+ * state machine for a @vport's nodes that are with pending RSCN (Registration
+ * State Change Notification).
+ *
+ * Return code
+ *   0 - Successful (currently alway return 0)
+ **/
 static int
 lpfc_rscn_recovery_check(struct lpfc_vport *vport)
 {
        struct lpfc_nodelist *ndlp = NULL;
 
-       /* Look at all nodes effected by pending RSCNs and move
-        * them to NPR state.
-        */
-
+       /* Move all affected nodes by pending RSCNs to NPR state. */
        list_for_each_entry(ndlp, &vport->fc_nodes, nlp_listp) {
-               if (ndlp->nlp_state == NLP_STE_UNUSED_NODE ||
-                   lpfc_rscn_payload_check(vport, ndlp->nlp_DID) == 0)
+               if (!NLP_CHK_NODE_ACT(ndlp) ||
+                   (ndlp->nlp_state == NLP_STE_UNUSED_NODE) ||
+                   !lpfc_rscn_payload_check(vport, ndlp->nlp_DID))
                        continue;
-
                lpfc_disc_state_machine(vport, ndlp, NULL,
-                                               NLP_EVT_DEVICE_RECOVERY);
+                                       NLP_EVT_DEVICE_RECOVERY);
+               lpfc_cancel_retry_delay_tmo(vport, ndlp);
+       }
+       return 0;
+}
 
-               /*
-                * Make sure NLP_DELAY_TMO is NOT running after a device
-                * recovery event.
-                */
-               if (ndlp->nlp_flag & NLP_DELAY_TMO)
-                       lpfc_cancel_retry_delay_tmo(vport, ndlp);
+/**
+ * lpfc_send_rscn_event - Send an RSCN event to management application
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ *
+ * lpfc_send_rscn_event sends an RSCN netlink event to management
+ * applications.
+ */
+static void
+lpfc_send_rscn_event(struct lpfc_vport *vport,
+               struct lpfc_iocbq *cmdiocb)
+{
+       struct lpfc_dmabuf *pcmd;
+       struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
+       uint32_t *payload_ptr;
+       uint32_t payload_len;
+       struct lpfc_rscn_event_header *rscn_event_data;
+
+       pcmd = (struct lpfc_dmabuf *) cmdiocb->context2;
+       payload_ptr = (uint32_t *) pcmd->virt;
+       payload_len = be32_to_cpu(*payload_ptr & ~ELS_CMD_MASK);
+
+       rscn_event_data = kmalloc(sizeof(struct lpfc_rscn_event_header) +
+               payload_len, GFP_KERNEL);
+       if (!rscn_event_data) {
+               lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                       "0147 Failed to allocate memory for RSCN event\n");
+               return;
        }
+       rscn_event_data->event_type = FC_REG_RSCN_EVENT;
+       rscn_event_data->payload_length = payload_len;
+       memcpy(rscn_event_data->rscn_payload, payload_ptr,
+               payload_len);
 
-       return 0;
+       fc_host_post_vendor_event(shost,
+               fc_get_event_number(),
+               sizeof(struct lpfc_els_event_header) + payload_len,
+               (char *)rscn_event_data,
+               LPFC_NL_VENDOR_ID);
+
+       kfree(rscn_event_data);
 }
 
+/**
+ * lpfc_els_rcv_rscn - Process an unsolicited rscn iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes an unsolicited RSCN (Registration State Change
+ * Notification) IOCB. First, the payload of the unsolicited RSCN is walked
+ * to invoke fc_host_post_event() routine to the FC transport layer. If the
+ * discover state machine is about to begin discovery, it just accepts the
+ * RSCN and the discovery process will satisfy the RSCN. If this RSCN only
+ * contains N_Port IDs for other vports on this HBA, it just accepts the
+ * RSCN and ignore processing it. If the state machine is in the recovery
+ * state, the fc_rscn_id_list of this @vport is walked and the
+ * lpfc_rscn_recovery_check() routine is invoked to send recovery event for
+ * all nodes that match RSCN payload. Otherwise, the lpfc_els_handle_rscn()
+ * routine is invoked to handle the RSCN event.
+ *
+ * Return code
+ *   0 - Just sent the acc response
+ *   1 - Sent the acc response and waited for name server completion
+ **/
 static int
 lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_nodelist *ndlp)
@@ -2905,7 +4083,7 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        uint32_t *lp, *datap;
        IOCB_t *icmd;
        uint32_t payload_len, length, nportid, *cmd;
-       int rscn_cnt = vport->fc_rscn_id_cnt;
+       int rscn_cnt;
        int rscn_id = 0, hba_id = 0;
        int i;
 
@@ -2918,7 +4096,12 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        /* RSCN received */
        lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
                         "0214 RSCN received Data: x%x x%x x%x x%x\n",
-                        vport->fc_flag, payload_len, *lp, rscn_cnt);
+                        vport->fc_flag, payload_len, *lp,
+                        vport->fc_rscn_id_cnt);
+
+       /* Send an RSCN event to the management application */
+       lpfc_send_rscn_event(vport, cmdiocb);
+
        for (i = 0; i < payload_len/sizeof(uint32_t); i++)
                fc_host_post_event(shost, fc_get_event_number(),
                        FCH_EVT_RSCN, lp[i]);
@@ -2953,10 +4136,10 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                if (rscn_id == hba_id) {
                        /* ALL NPortIDs in RSCN are on HBA */
                        lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
-                                        "0214 Ignore RSCN "
+                                        "0219 Ignore RSCN "
                                         "Data: x%x x%x x%x x%x\n",
                                         vport->fc_flag, payload_len,
-                                        *lp, rscn_cnt);
+                                        *lp, vport->fc_rscn_id_cnt);
                        lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_ELS_UNSOL,
                                "RCV RSCN vport:  did:x%x/ste:x%x flg:x%x",
                                ndlp->nlp_DID, vport->port_state,
@@ -2968,6 +4151,20 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                }
        }
 
+       spin_lock_irq(shost->host_lock);
+       if (vport->fc_rscn_flush) {
+               /* Another thread is walking fc_rscn_id_list on this vport */
+               vport->fc_flag |= FC_RSCN_DISCOVERY;
+               spin_unlock_irq(shost->host_lock);
+               /* Send back ACC */
+               lpfc_els_rsp_acc(vport, ELS_CMD_ACC, cmdiocb, ndlp, NULL);
+               return 0;
+       }
+       /* Indicate we are walking fc_rscn_id_list on this vport */
+       vport->fc_rscn_flush = 1;
+       spin_unlock_irq(shost->host_lock);
+       /* Get the array count after successfully have the token */
+       rscn_cnt = vport->fc_rscn_id_cnt;
        /* If we are already processing an RSCN, save the received
         * RSCN payload buffer, cmdiocb->context2 to process later.
         */
@@ -2976,10 +4173,10 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                        "RCV RSCN defer:  did:x%x/ste:x%x flg:x%x",
                        ndlp->nlp_DID, vport->port_state, ndlp->nlp_flag);
 
+               spin_lock_irq(shost->host_lock);
                vport->fc_flag |= FC_RSCN_DEFERRED;
                if ((rscn_cnt < FC_MAX_HOLD_RSCN) &&
                    !(vport->fc_flag & FC_RSCN_DISCOVERY)) {
-                       spin_lock_irq(shost->host_lock);
                        vport->fc_flag |= FC_RSCN_MODE;
                        spin_unlock_irq(shost->host_lock);
                        if (rscn_cnt) {
@@ -2989,7 +4186,7 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                        if ((rscn_cnt) &&
                            (payload_len + length <= LPFC_BPL_SIZE)) {
                                *cmd &= ELS_CMD_MASK;
-                               *cmd |= be32_to_cpu(payload_len + length);
+                               *cmd |= cpu_to_be32(payload_len + length);
                                memcpy(((uint8_t *)cmd) + length, lp,
                                       payload_len);
                        } else {
@@ -3000,7 +4197,6 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                                 */
                                cmdiocb->context2 = NULL;
                        }
-
                        /* Deferred RSCN */
                        lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY,
                                         "0235 Deferred RSCN "
@@ -3008,7 +4204,6 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                                         vport->fc_rscn_id_cnt, vport->fc_flag,
                                         vport->port_state);
                } else {
-                       spin_lock_irq(shost->host_lock);
                        vport->fc_flag |= FC_RSCN_DISCOVERY;
                        spin_unlock_irq(shost->host_lock);
                        /* ReDiscovery RSCN */
@@ -3018,15 +4213,17 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                                         vport->fc_rscn_id_cnt, vport->fc_flag,
                                         vport->port_state);
                }
+               /* Indicate we are done walking fc_rscn_id_list on this vport */
+               vport->fc_rscn_flush = 0;
                /* Send back ACC */
                lpfc_els_rsp_acc(vport, ELS_CMD_ACC, cmdiocb, ndlp, NULL);
-
                /* send RECOVERY event for ALL nodes that match RSCN payload */
                lpfc_rscn_recovery_check(vport);
+               spin_lock_irq(shost->host_lock);
                vport->fc_flag &= ~FC_RSCN_DEFERRED;
+               spin_unlock_irq(shost->host_lock);
                return 0;
        }
-
        lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_ELS_UNSOL,
                "RCV RSCN:        did:x%x/ste:x%x flg:x%x",
                ndlp->nlp_DID, vport->port_state, ndlp->nlp_flag);
@@ -3035,23 +4232,37 @@ lpfc_els_rcv_rscn(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        vport->fc_flag |= FC_RSCN_MODE;
        spin_unlock_irq(shost->host_lock);
        vport->fc_rscn_id_list[vport->fc_rscn_id_cnt++] = pcmd;
+       /* Indicate we are done walking fc_rscn_id_list on this vport */
+       vport->fc_rscn_flush = 0;
        /*
         * If we zero, cmdiocb->context2, the calling routine will
         * not try to free it.
         */
        cmdiocb->context2 = NULL;
-
        lpfc_set_disctmo(vport);
-
        /* Send back ACC */
        lpfc_els_rsp_acc(vport, ELS_CMD_ACC, cmdiocb, ndlp, NULL);
-
        /* send RECOVERY event for ALL nodes that match RSCN payload */
        lpfc_rscn_recovery_check(vport);
-
        return lpfc_els_handle_rscn(vport);
 }
 
+/**
+ * lpfc_els_handle_rscn - Handle rscn for a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine handles the Registration State Configuration Notification
+ * (RSCN) for a @vport. If login to NameServer does not exist, a new ndlp shall
+ * be created and a Port Login (PLOGI) to the NameServer is issued. Otherwise,
+ * if the ndlp to NameServer exists, a Common Transport (CT) command to the
+ * NameServer shall be issued. If CT command to the NameServer fails to be
+ * issued, the lpfc_els_flush_rscn() routine shall be invoked to clean up any
+ * RSCN activities with the @vport.
+ *
+ * Return code
+ *   0 - Cleaned up rscn on the @vport
+ *   1 - Wait for plogi to name server before proceed
+ **/
 int
 lpfc_els_handle_rscn(struct lpfc_vport *vport)
 {
@@ -3078,7 +4289,8 @@ lpfc_els_handle_rscn(struct lpfc_vport *vport)
        vport->num_disc_nodes = 0;
 
        ndlp = lpfc_findnode_did(vport, NameServer_DID);
-       if (ndlp && ndlp->nlp_state == NLP_STE_UNMAPPED_NODE) {
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp)
+           && ndlp->nlp_state == NLP_STE_UNMAPPED_NODE) {
                /* Good ndlp, issue CT Request to NameServer */
                if (lpfc_ns_cmd(vport, SLI_CTNS_GID_FT, 0, 0) == 0)
                        /* Wait for NameServer query cmpl before we can
@@ -3088,31 +4300,66 @@ lpfc_els_handle_rscn(struct lpfc_vport *vport)
                /* If login to NameServer does not exist, issue one */
                /* Good status, issue PLOGI to NameServer */
                ndlp = lpfc_findnode_did(vport, NameServer_DID);
-               if (ndlp)
+               if (ndlp && NLP_CHK_NODE_ACT(ndlp))
                        /* Wait for NameServer login cmpl before we can
                           continue */
                        return 1;
 
-               ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
-               if (!ndlp) {
-                       lpfc_els_flush_rscn(vport);
-                       return 0;
+               if (ndlp) {
+                       ndlp = lpfc_enable_node(vport, ndlp,
+                                               NLP_STE_PLOGI_ISSUE);
+                       if (!ndlp) {
+                               lpfc_els_flush_rscn(vport);
+                               return 0;
+                       }
+                       ndlp->nlp_prev_state = NLP_STE_UNUSED_NODE;
                } else {
+                       ndlp = mempool_alloc(phba->nlp_mem_pool, GFP_KERNEL);
+                       if (!ndlp) {
+                               lpfc_els_flush_rscn(vport);
+                               return 0;
+                       }
                        lpfc_nlp_init(vport, ndlp, NameServer_DID);
-                       ndlp->nlp_type |= NLP_FABRIC;
                        ndlp->nlp_prev_state = ndlp->nlp_state;
                        lpfc_nlp_set_state(vport, ndlp, NLP_STE_PLOGI_ISSUE);
-                       lpfc_issue_els_plogi(vport, NameServer_DID, 0);
-                       /* Wait for NameServer login cmpl before we can
-                          continue */
-                       return 1;
                }
+               ndlp->nlp_type |= NLP_FABRIC;
+               lpfc_issue_els_plogi(vport, NameServer_DID, 0);
+               /* Wait for NameServer login cmpl before we can
+                * continue
+                */
+               return 1;
        }
 
        lpfc_els_flush_rscn(vport);
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_flogi - Process an unsolicited flogi iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Fabric Login (FLOGI) IOCB received as an ELS
+ * unsolicited event. An unsolicited FLOGI can be received in a point-to-
+ * point topology. As an unsolicited FLOGI should not be received in a loop
+ * mode, any unsolicited FLOGI received in loop mode shall be ignored. The
+ * lpfc_check_sparm() routine is invoked to check the parameters in the
+ * unsolicited FLOGI. If parameters validation failed, the routine
+ * lpfc_els_rsp_reject() shall be called with reject reason code set to
+ * LSEXP_SPARM_OPTIONS to reject the FLOGI. Otherwise, the Port WWN in the
+ * FLOGI shall be compared with the Port WWN of the @vport to determine who
+ * will initiate PLOGI. The higher lexicographical value party shall has
+ * higher priority (as the winning port) and will initiate PLOGI and
+ * communicate Port_IDs (Addresses) for both nodes in PLOGI. The result
+ * of this will be marked in the @vport fc_flag field with FC_PT2PT_PLOGI
+ * and then the lpfc_els_rsp_acc() routine is invoked to accept the FLOGI.
+ *
+ * Return code
+ *   0 - Successfully processed the unsolicited flogi
+ *   1 - Failed to process the unsolicited flogi
+ **/
 static int
 lpfc_els_rcv_flogi(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                   struct lpfc_nodelist *ndlp)
@@ -3150,7 +4397,7 @@ lpfc_els_rcv_flogi(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
 
        did = Fabric_DID;
 
-       if ((lpfc_check_sparm(vport, ndlp, sp, CLASS3))) {
+       if ((lpfc_check_sparm(vport, ndlp, sp, CLASS3, 1))) {
                /* For a FLOGI we accept, then if our portname is greater
                 * then the remote portname we initiate Nport login.
                 */
@@ -3167,7 +4414,7 @@ lpfc_els_rcv_flogi(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                        lpfc_init_link(phba, mbox,
                                       phba->cfg_topology,
                                       phba->cfg_link_speed);
-                       mbox->mb.un.varInitLnk.lipsr_AL_PA = 0;
+                       mbox->u.mb.un.varInitLnk.lipsr_AL_PA = 0;
                        mbox->mbox_cmpl = lpfc_sli_def_mbox_cmpl;
                        mbox->vport = vport;
                        rc = lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT);
@@ -3202,6 +4449,22 @@ lpfc_els_rcv_flogi(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_rnid - Process an unsolicited rnid iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Request Node Identification Data (RNID) IOCB
+ * received as an ELS unsolicited event. Only when the RNID specified format
+ * 0x0 or 0xDF (Topology Discovery Specific Node Identification Data)
+ * present, this routine will invoke the lpfc_els_rsp_rnid_acc() routine to
+ * Accept (ACC) the RNID ELS command. All the other RNID formats are
+ * rejected by invoking the lpfc_els_rsp_reject() routine.
+ *
+ * Return code
+ *   0 - Successfully processed rnid iocb (currently always return 0)
+ **/
 static int
 lpfc_els_rcv_rnid(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_nodelist *ndlp)
@@ -3241,6 +4504,19 @@ lpfc_els_rcv_rnid(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_lirr - Process an unsolicited lirr iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes a Link Incident Report Registration(LIRR) IOCB
+ * received as an ELS unsolicited event. Currently, this function just invokes
+ * the lpfc_els_rsp_reject() routine to reject the LIRR IOCB unconditionally.
+ *
+ * Return code
+ *   0 - Successfully processed lirr iocb (currently always return 0)
+ **/
 static int
 lpfc_els_rcv_lirr(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_nodelist *ndlp)
@@ -3256,11 +4532,51 @@ lpfc_els_rcv_lirr(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_rrq - Process an unsolicited rrq iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes a Reinstate Recovery Qualifier (RRQ) IOCB
+ * received as an ELS unsolicited event. A request to RRQ shall only
+ * be accepted if the Originator Nx_Port N_Port_ID or the Responder
+ * Nx_Port N_Port_ID of the target Exchange is the same as the
+ * N_Port_ID of the Nx_Port that makes the request. If the RRQ is
+ * not accepted, an LS_RJT with reason code "Unable to perform
+ * command request" and reason code explanation "Invalid Originator
+ * S_ID" shall be returned. For now, we just unconditionally accept
+ * RRQ from the target.
+ **/
+static void
+lpfc_els_rcv_rrq(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
+                struct lpfc_nodelist *ndlp)
+{
+       lpfc_els_rsp_acc(vport, ELS_CMD_ACC, cmdiocb, ndlp, NULL);
+}
+
+/**
+ * lpfc_els_rsp_rps_acc - Completion callbk func for MBX_READ_LNK_STAT mbox cmd
+ * @phba: pointer to lpfc hba data structure.
+ * @pmb: pointer to the driver internal queue element for mailbox command.
+ *
+ * This routine is the completion callback function for the MBX_READ_LNK_STAT
+ * mailbox command. This callback function is to actually send the Accept
+ * (ACC) response to a Read Port Status (RPS) unsolicited IOCB event. It
+ * collects the link statistics from the completion of the MBX_READ_LNK_STAT
+ * mailbox command, constructs the RPS response with the link statistics
+ * collected, and then invokes the lpfc_sli_issue_iocb() routine to send ACC
+ * response to the RPS.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the RPS Accept Response ELS IOCB command.
+ *
+ **/
 static void
 lpfc_els_rsp_rps_acc(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 {
-       struct lpfc_sli *psli = &phba->sli;
-       struct lpfc_sli_ring *pring = &psli->ring[LPFC_ELS_RING];
        MAILBOX_t *mb;
        IOCB_t *icmd;
        RPS_RSP *rps_rsp;
@@ -3270,7 +4586,7 @@ lpfc_els_rsp_rps_acc(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
        uint16_t xri, status;
        uint32_t cmdsize;
 
-       mb = &pmb->mb;
+       mb = &pmb->u.mb;
 
        ndlp = (struct lpfc_nodelist *) pmb->context2;
        xri = (uint16_t) ((unsigned long)(pmb->context1));
@@ -3287,7 +4603,10 @@ lpfc_els_rsp_rps_acc(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
        elsiocb = lpfc_prep_els_iocb(phba->pport, 0, cmdsize,
                                     lpfc_max_els_tries, ndlp,
                                     ndlp->nlp_DID, ELS_CMD_ACC);
+
+       /* Decrement the ndlp reference count from previous mbox command */
        lpfc_nlp_put(ndlp);
+
        if (!elsiocb)
                return;
 
@@ -3307,13 +4626,13 @@ lpfc_els_rsp_rps_acc(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
                status |= 0x4;
 
        rps_rsp->rsvd1 = 0;
-       rps_rsp->portStatus = be16_to_cpu(status);
-       rps_rsp->linkFailureCnt = be32_to_cpu(mb->un.varRdLnk.linkFailureCnt);
-       rps_rsp->lossSyncCnt = be32_to_cpu(mb->un.varRdLnk.lossSyncCnt);
-       rps_rsp->lossSignalCnt = be32_to_cpu(mb->un.varRdLnk.lossSignalCnt);
-       rps_rsp->primSeqErrCnt = be32_to_cpu(mb->un.varRdLnk.primSeqErrCnt);
-       rps_rsp->invalidXmitWord = be32_to_cpu(mb->un.varRdLnk.invalidXmitWord);
-       rps_rsp->crcCnt = be32_to_cpu(mb->un.varRdLnk.crcCnt);
+       rps_rsp->portStatus = cpu_to_be16(status);
+       rps_rsp->linkFailureCnt = cpu_to_be32(mb->un.varRdLnk.linkFailureCnt);
+       rps_rsp->lossSyncCnt = cpu_to_be32(mb->un.varRdLnk.lossSyncCnt);
+       rps_rsp->lossSignalCnt = cpu_to_be32(mb->un.varRdLnk.lossSignalCnt);
+       rps_rsp->primSeqErrCnt = cpu_to_be32(mb->un.varRdLnk.primSeqErrCnt);
+       rps_rsp->invalidXmitWord = cpu_to_be32(mb->un.varRdLnk.invalidXmitWord);
+       rps_rsp->crcCnt = cpu_to_be32(mb->un.varRdLnk.crcCnt);
        /* Xmit ELS RPS ACC response tag <ulpIoTag> */
        lpfc_printf_vlog(ndlp->vport, KERN_INFO, LOG_ELS,
                         "0118 Xmit ELS RPS ACC response tag x%x xri x%x, "
@@ -3323,11 +4642,29 @@ lpfc_els_rsp_rps_acc(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
                         ndlp->nlp_rpi);
        elsiocb->iocb_cmpl = lpfc_cmpl_els_rsp;
        phba->fc_stat.elsXmitACC++;
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR)
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) == IOCB_ERROR)
                lpfc_els_free_iocb(phba, elsiocb);
        return;
 }
 
+/**
+ * lpfc_els_rcv_rps - Process an unsolicited rps iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Read Port Status (RPS) IOCB received as an
+ * ELS unsolicited event. It first checks the remote port state. If the
+ * remote port is not in NLP_STE_UNMAPPED_NODE state or NLP_STE_MAPPED_NODE
+ * state, it invokes the lpfc_els_rsp_reject() routine to send the reject
+ * response. Otherwise, it issue the MBX_READ_LNK_STAT mailbox command
+ * for reading the HBA link statistics. It is for the callback function,
+ * lpfc_els_rsp_rps_acc(), set to the MBX_READ_LNK_STAT mailbox command
+ * to actually sending out RPS Accept (ACC) response.
+ *
+ * Return codes
+ *   0 - Successfully processed rps iocb (currently always return 0)
+ **/
 static int
 lpfc_els_rcv_rps(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                 struct lpfc_nodelist *ndlp)
@@ -3341,14 +4678,9 @@ lpfc_els_rcv_rps(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        struct ls_rjt stat;
 
        if ((ndlp->nlp_state != NLP_STE_UNMAPPED_NODE) &&
-           (ndlp->nlp_state != NLP_STE_MAPPED_NODE)) {
-               stat.un.b.lsRjtRsvd0 = 0;
-               stat.un.b.lsRjtRsnCode = LSRJT_UNABLE_TPC;
-               stat.un.b.lsRjtRsnCodeExp = LSEXP_CANT_GIVE_DATA;
-               stat.un.b.vendorUnique = 0;
-               lpfc_els_rsp_reject(vport, stat.un.lsRjtError, cmdiocb, ndlp,
-                       NULL);
-       }
+           (ndlp->nlp_state != NLP_STE_MAPPED_NODE))
+               /* reject the unsolicited RPS request and done with it */
+               goto reject_out;
 
        pcmd = (struct lpfc_dmabuf *) cmdiocb->context2;
        lp = (uint32_t *) pcmd->virt;
@@ -3370,15 +4702,20 @@ lpfc_els_rcv_rps(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                        mbox->context2 = lpfc_nlp_get(ndlp);
                        mbox->vport = vport;
                        mbox->mbox_cmpl = lpfc_els_rsp_rps_acc;
-                       if (lpfc_sli_issue_mbox (phba, mbox, MBX_NOWAIT)
+                       if (lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT)
                                != MBX_NOT_FINISHED)
                                /* Mbox completion will send ELS Response */
                                return 0;
-
+                       /* Decrement reference count used for the failed mbox
+                        * command.
+                        */
                        lpfc_nlp_put(ndlp);
                        mempool_free(mbox, phba->mbox_mem_pool);
                }
        }
+
+reject_out:
+       /* issue rejection response */
        stat.un.b.lsRjtRsvd0 = 0;
        stat.un.b.lsRjtRsnCode = LSRJT_UNABLE_TPC;
        stat.un.b.lsRjtRsnCodeExp = LSEXP_CANT_GIVE_DATA;
@@ -3387,6 +4724,25 @@ lpfc_els_rcv_rps(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rsp_rpl_acc - Issue an accept rpl els command
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdsize: size of the ELS command.
+ * @oldiocb: pointer to the original lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine issuees an Accept (ACC) Read Port List (RPL) ELS command.
+ * It is to be called by the lpfc_els_rcv_rpl() routine to accept the RPL.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the RPL Accept Response ELS command.
+ *
+ * Return code
+ *   0 - Successfully issued ACC RPL ELS command
+ *   1 - Failed to issue ACC RPL ELS command
+ **/
 static int
 lpfc_els_rsp_rpl_acc(struct lpfc_vport *vport, uint16_t cmdsize,
                     struct lpfc_iocbq *oldiocb, struct lpfc_nodelist *ndlp)
@@ -3395,8 +4751,6 @@ lpfc_els_rsp_rpl_acc(struct lpfc_vport *vport, uint16_t cmdsize,
        IOCB_t *icmd, *oldcmd;
        RPL_RSP rpl_rsp;
        struct lpfc_iocbq *elsiocb;
-       struct lpfc_sli *psli = &phba->sli;
-       struct lpfc_sli_ring *pring = &psli->ring[LPFC_ELS_RING];
        uint8_t *pcmd;
 
        elsiocb = lpfc_prep_els_iocb(vport, 0, cmdsize, oldiocb->retry, ndlp,
@@ -3433,13 +4787,30 @@ lpfc_els_rsp_rpl_acc(struct lpfc_vport *vport, uint16_t cmdsize,
                         ndlp->nlp_rpi);
        elsiocb->iocb_cmpl = lpfc_cmpl_els_rsp;
        phba->fc_stat.elsXmitACC++;
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
                lpfc_els_free_iocb(phba, elsiocb);
                return 1;
        }
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_rpl - Process an unsolicited rpl iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Read Port List (RPL) IOCB received as an ELS
+ * unsolicited event. It first checks the remote port state. If the remote
+ * port is not in NLP_STE_UNMAPPED_NODE and NLP_STE_MAPPED_NODE states, it
+ * invokes the lpfc_els_rsp_reject() routine to send reject response.
+ * Otherwise, this routine then invokes the lpfc_els_rsp_rpl_acc() routine
+ * to accept the RPL.
+ *
+ * Return code
+ *   0 - Successfully processed rpl iocb (currently always return 0)
+ **/
 static int
 lpfc_els_rcv_rpl(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                 struct lpfc_nodelist *ndlp)
@@ -3453,12 +4824,15 @@ lpfc_els_rcv_rpl(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
 
        if ((ndlp->nlp_state != NLP_STE_UNMAPPED_NODE) &&
            (ndlp->nlp_state != NLP_STE_MAPPED_NODE)) {
+               /* issue rejection response */
                stat.un.b.lsRjtRsvd0 = 0;
                stat.un.b.lsRjtRsnCode = LSRJT_UNABLE_TPC;
                stat.un.b.lsRjtRsnCodeExp = LSEXP_CANT_GIVE_DATA;
                stat.un.b.vendorUnique = 0;
                lpfc_els_rsp_reject(vport, stat.un.lsRjtError, cmdiocb, ndlp,
                        NULL);
+               /* rejected the unsolicited RPL request and done with it */
+               return 0;
        }
 
        pcmd = (struct lpfc_dmabuf *) cmdiocb->context2;
@@ -3480,6 +4854,30 @@ lpfc_els_rcv_rpl(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_farp - Process an unsolicited farp request els command
+ * @vport: pointer to a virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Fibre Channel Address Resolution Protocol
+ * (FARP) Request IOCB received as an ELS unsolicited event. Currently,
+ * the lpfc driver only supports matching on WWPN or WWNN for FARP. As such,
+ * FARP_MATCH_PORT flag and FARP_MATCH_NODE flag are checked against the
+ * Match Flag in the FARP request IOCB: if FARP_MATCH_PORT flag is set, the
+ * remote PortName is compared against the FC PortName stored in the @vport
+ * data structure; if FARP_MATCH_NODE flag is set, the remote NodeName is
+ * compared against the FC NodeName stored in the @vport data structure.
+ * If any of these matches and the FARP_REQUEST_FARPR flag is set in the
+ * FARP request IOCB Response Flag, the lpfc_issue_els_farpr() routine is
+ * invoked to send out FARP Response to the remote node. Before sending the
+ * FARP Response, however, the FARP_REQUEST_PLOGI flag is check in the FARP
+ * request IOCB Response Flag and, if it is set, the lpfc_issue_els_plogi()
+ * routine is invoked to log into the remote port first.
+ *
+ * Return code
+ *   0 - Either the FARP Match Mode not supported or successfully processed
+ **/
 static int
 lpfc_els_rcv_farp(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                  struct lpfc_nodelist *ndlp)
@@ -3539,6 +4937,20 @@ lpfc_els_rcv_farp(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_farpr - Process an unsolicited farp response iocb
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes Fibre Channel Address Resolution Protocol
+ * Response (FARPR) IOCB received as an ELS unsolicited event. It simply
+ * invokes the lpfc_els_rsp_acc() routine to the remote node to accept
+ * the FARP response request.
+ *
+ * Return code
+ *   0 - Successfully processed FARPR IOCB (currently always return 0)
+ **/
 static int
 lpfc_els_rcv_farpr(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                   struct lpfc_nodelist  *ndlp)
@@ -3563,117 +4975,95 @@ lpfc_els_rcv_farpr(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
        return 0;
 }
 
+/**
+ * lpfc_els_rcv_fan - Process an unsolicited fan iocb command
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @fan_ndlp: pointer to a node-list data structure.
+ *
+ * This routine processes a Fabric Address Notification (FAN) IOCB
+ * command received as an ELS unsolicited event. The FAN ELS command will
+ * only be processed on a physical port (i.e., the @vport represents the
+ * physical port). The fabric NodeName and PortName from the FAN IOCB are
+ * compared against those in the phba data structure. If any of those is
+ * different, the lpfc_initial_flogi() routine is invoked to initialize
+ * Fabric Login (FLOGI) to the fabric to start the discover over. Otherwise,
+ * if both of those are identical, the lpfc_issue_fabric_reglogin() routine
+ * is invoked to register login to the fabric.
+ *
+ * Return code
+ *   0 - Successfully processed fan iocb (currently always return 0).
+ **/
 static int
 lpfc_els_rcv_fan(struct lpfc_vport *vport, struct lpfc_iocbq *cmdiocb,
                 struct lpfc_nodelist *fan_ndlp)
 {
-       struct lpfc_dmabuf *pcmd;
+       struct lpfc_hba *phba = vport->phba;
        uint32_t *lp;
-       IOCB_t *icmd;
-       uint32_t cmd, did;
        FAN *fp;
-       struct lpfc_nodelist *ndlp, *next_ndlp;
-       struct lpfc_hba *phba = vport->phba;
-
-       /* FAN received */
-       lpfc_printf_vlog(vport, KERN_INFO, LOG_ELS,
-                        "0265 FAN received\n");
-       icmd = &cmdiocb->iocb;
-       did = icmd->un.elsreq64.remoteID;
-       pcmd = (struct lpfc_dmabuf *)cmdiocb->context2;
-       lp = (uint32_t *)pcmd->virt;
-
-       cmd = *lp++;
-       fp = (FAN *) lp;
 
+       lpfc_printf_vlog(vport, KERN_INFO, LOG_ELS, "0265 FAN received\n");
+       lp = (uint32_t *)((struct lpfc_dmabuf *)cmdiocb->context2)->virt;
+       fp = (FAN *) ++lp;
        /* FAN received; Fan does not have a reply sequence */
-
-       if (phba->pport->port_state == LPFC_LOCAL_CFG_LINK) {
+       if ((vport == phba->pport) &&
+           (vport->port_state == LPFC_LOCAL_CFG_LINK)) {
                if ((memcmp(&phba->fc_fabparam.nodeName, &fp->FnodeName,
-                       sizeof(struct lpfc_name)) != 0) ||
+                           sizeof(struct lpfc_name))) ||
                    (memcmp(&phba->fc_fabparam.portName, &fp->FportName,
-                       sizeof(struct lpfc_name)) != 0)) {
-                       /*
-                        * This node has switched fabrics.  FLOGI is required
-                        * Clean up the old rpi's
-                        */
-
-                       list_for_each_entry_safe(ndlp, next_ndlp,
-                                                &vport->fc_nodes, nlp_listp) {
-                               if (ndlp->nlp_state != NLP_STE_NPR_NODE)
-                                       continue;
-                               if (ndlp->nlp_type & NLP_FABRIC) {
-                                       /*
-                                        * Clean up old Fabric, Nameserver and
-                                        * other NLP_FABRIC logins
-                                        */
-                                       lpfc_drop_node(vport, ndlp);
-
-                               } else if (!(ndlp->nlp_flag & NLP_NPR_ADISC)) {
-                                       /* Fail outstanding I/O now since this
-                                        * device is marked for PLOGI
-                                        */
-                                       lpfc_unreg_rpi(vport, ndlp);
-                               }
-                       }
-
+                           sizeof(struct lpfc_name)))) {
+                       /* This port has switched fabrics. FLOGI is required */
                        lpfc_initial_flogi(vport);
-                       return 0;
-               }
-               /* Discovery not needed,
-                * move the nodes to their original state.
-                */
-               list_for_each_entry_safe(ndlp, next_ndlp, &vport->fc_nodes,
-                                        nlp_listp) {
-                       if (ndlp->nlp_state != NLP_STE_NPR_NODE)
-                               continue;
-
-                       switch (ndlp->nlp_prev_state) {
-                       case NLP_STE_UNMAPPED_NODE:
-                               ndlp->nlp_prev_state = NLP_STE_NPR_NODE;
-                               lpfc_nlp_set_state(vport, ndlp,
-                                                  NLP_STE_UNMAPPED_NODE);
-                               break;
-
-                       case NLP_STE_MAPPED_NODE:
-                               ndlp->nlp_prev_state = NLP_STE_NPR_NODE;
-                               lpfc_nlp_set_state(vport, ndlp,
-                                                  NLP_STE_MAPPED_NODE);
-                               break;
-
-                       default:
-                               break;
-                       }
+               } else {
+                       /* FAN verified - skip FLOGI */
+                       vport->fc_myDID = vport->fc_prevDID;
+                       if (phba->sli_rev < LPFC_SLI_REV4)
+                               lpfc_issue_fabric_reglogin(vport);
+                       else
+                               lpfc_issue_reg_vfi(vport);
                }
-
-               /* Start discovery - this should just do CLEAR_LA */
-               lpfc_disc_start(vport);
        }
        return 0;
 }
 
+/**
+ * lpfc_els_timeout - Handler funciton to the els timer
+ * @ptr: holder for the timer function associated data.
+ *
+ * This routine is invoked by the ELS timer after timeout. It posts the ELS
+ * timer timeout event by setting the WORKER_ELS_TMO bit to the work port
+ * event bitmap and then invokes the lpfc_worker_wake_up() routine to wake
+ * up the worker thread. It is for the worker thread to invoke the routine
+ * lpfc_els_timeout_handler() to work on the posted event WORKER_ELS_TMO.
+ **/
 void
 lpfc_els_timeout(unsigned long ptr)
 {
        struct lpfc_vport *vport = (struct lpfc_vport *) ptr;
        struct lpfc_hba   *phba = vport->phba;
+       uint32_t tmo_posted;
        unsigned long iflag;
 
        spin_lock_irqsave(&vport->work_port_lock, iflag);
-       if ((vport->work_port_events & WORKER_ELS_TMO) == 0) {
+       tmo_posted = vport->work_port_events & WORKER_ELS_TMO;
+       if (!tmo_posted)
                vport->work_port_events |= WORKER_ELS_TMO;
-               spin_unlock_irqrestore(&vport->work_port_lock, iflag);
+       spin_unlock_irqrestore(&vport->work_port_lock, iflag);
 
-               spin_lock_irqsave(&phba->hbalock, iflag);
-               if (phba->work_wait)
-                       lpfc_worker_wake_up(phba);
-               spin_unlock_irqrestore(&phba->hbalock, iflag);
-       }
-       else
-               spin_unlock_irqrestore(&vport->work_port_lock, iflag);
+       if (!tmo_posted)
+               lpfc_worker_wake_up(phba);
        return;
 }
 
+/**
+ * lpfc_els_timeout_handler - Process an els timeout event
+ * @vport: pointer to a virtual N_Port data structure.
+ *
+ * This routine is the actual handler function that processes an ELS timeout
+ * event. It walks the ELS ring to get and abort all the IOCBs (except the
+ * ABORT/CLOSE/FARP/FARPR/FDISC), which are associated with the @vport by
+ * invoking the lpfc_sli_issue_abort_iotag() routine.
+ **/
 void
 lpfc_els_timeout_handler(struct lpfc_vport *vport)
 {
@@ -3686,10 +5076,6 @@ lpfc_els_timeout_handler(struct lpfc_vport *vport)
        uint32_t timeout;
        uint32_t remote_ID = 0xffffffff;
 
-       /* If the timer is already canceled do nothing */
-       if ((vport->work_port_events & WORKER_ELS_TMO) == 0) {
-               return;
-       }
        spin_lock_irq(&phba->hbalock);
        timeout = (uint32_t)(phba->fc_ratov << 1);
 
@@ -3715,9 +5101,6 @@ lpfc_els_timeout_handler(struct lpfc_vport *vport)
                    els_command == ELS_CMD_FDISC)
                        continue;
 
-               if (vport != piocb->vport)
-                       continue;
-
                if (piocb->drvrTimeout > 0) {
                        if (piocb->drvrTimeout >= timeout)
                                piocb->drvrTimeout -= timeout;
@@ -3732,7 +5115,7 @@ lpfc_els_timeout_handler(struct lpfc_vport *vport)
                else {
                        struct lpfc_nodelist *ndlp;
                        ndlp = __lpfc_findnode_rpi(vport, cmd->ulpContext);
-                       if (ndlp)
+                       if (ndlp && NLP_CHK_NODE_ACT(ndlp))
                                remote_ID = ndlp->nlp_DID;
                }
                lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
@@ -3747,6 +5130,26 @@ lpfc_els_timeout_handler(struct lpfc_vport *vport)
                mod_timer(&vport->els_tmofunc, jiffies + HZ * timeout);
 }
 
+/**
+ * lpfc_els_flush_cmd - Clean up the outstanding els commands to a vport
+ * @vport: pointer to a host virtual N_Port data structure.
+ *
+ * This routine is used to clean up all the outstanding ELS commands on a
+ * @vport. It first aborts the @vport by invoking lpfc_fabric_abort_vport()
+ * routine. After that, it walks the ELS transmit queue to remove all the
+ * IOCBs with the @vport other than the QUE_RING and ABORT/CLOSE IOCBs. For
+ * the IOCBs with a non-NULL completion callback function, the callback
+ * function will be invoked with the status set to IOSTAT_LOCAL_REJECT and
+ * un.ulpWord[4] set to IOERR_SLI_ABORTED. For IOCBs with a NULL completion
+ * callback function, the IOCB will simply be released. Finally, it walks
+ * the ELS transmit completion queue to issue an abort IOCB to any transmit
+ * completion queue IOCB that is associated with the @vport and is not
+ * an IOCB from libdfc (i.e., the management plane IOCBs that are not
+ * part of the discovery state machine) out to HBA by invoking the
+ * lpfc_sli_issue_abort_iotag() routine. Note that this function issues the
+ * abort IOCB to any transmit completion queueed IOCB, it does not guarantee
+ * the IOCBs are aborted when this function returns.
+ **/
 void
 lpfc_els_flush_cmd(struct lpfc_vport *vport)
 {
@@ -3792,23 +5195,30 @@ lpfc_els_flush_cmd(struct lpfc_vport *vport)
        }
        spin_unlock_irq(&phba->hbalock);
 
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               cmd = &piocb->iocb;
-               list_del_init(&piocb->list);
-
-               if (!piocb->iocb_cmpl)
-                       lpfc_sli_release_iocbq(phba, piocb);
-               else {
-                       cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-                       cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-                       (piocb->iocb_cmpl) (phba, piocb, piocb);
-               }
-       }
+       /* Cancell all the IOCBs from the completions list */
+       lpfc_sli_cancel_iocbs(phba, &completions, IOSTAT_LOCAL_REJECT,
+                             IOERR_SLI_ABORTED);
 
        return;
 }
 
+/**
+ * lpfc_els_flush_all_cmd - Clean up all the outstanding els commands to a HBA
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine is used to clean up all the outstanding ELS commands on a
+ * @phba. It first aborts the @phba by invoking the lpfc_fabric_abort_hba()
+ * routine. After that, it walks the ELS transmit queue to remove all the
+ * IOCBs to the @phba other than the QUE_RING and ABORT/CLOSE IOCBs. For
+ * the IOCBs with the completion callback function associated, the callback
+ * function will be invoked with the status set to IOSTAT_LOCAL_REJECT and
+ * un.ulpWord[4] set to IOERR_SLI_ABORTED. For IOCBs without the completion
+ * callback function associated, the IOCB will simply be released. Finally,
+ * it walks the ELS transmit completion queue to issue an abort IOCB to any
+ * transmit completion queue IOCB that is not an IOCB from libdfc (i.e., the
+ * management plane IOCBs that are not part of the discovery state machine)
+ * out to HBA by invoking the lpfc_sli_issue_abort_iotag() routine.
+ **/
 void
 lpfc_els_flush_all_cmd(struct lpfc_hba  *phba)
 {
@@ -3838,21 +5248,175 @@ lpfc_els_flush_all_cmd(struct lpfc_hba  *phba)
                lpfc_sli_issue_abort_iotag(phba, pring, piocb);
        }
        spin_unlock_irq(&phba->hbalock);
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               cmd = &piocb->iocb;
-               list_del_init(&piocb->list);
-               if (!piocb->iocb_cmpl)
-                       lpfc_sli_release_iocbq(phba, piocb);
-               else {
-                       cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-                       cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-                       (piocb->iocb_cmpl) (phba, piocb, piocb);
+
+       /* Cancel all the IOCBs from the completions list */
+       lpfc_sli_cancel_iocbs(phba, &completions, IOSTAT_LOCAL_REJECT,
+                             IOERR_SLI_ABORTED);
+
+       return;
+}
+
+/**
+ * lpfc_send_els_failure_event - Posts an ELS command failure event
+ * @phba: Pointer to hba context object.
+ * @cmdiocbp: Pointer to command iocb which reported error.
+ * @rspiocbp: Pointer to response iocb which reported error.
+ *
+ * This function sends an event when there is an ELS command
+ * failure.
+ **/
+void
+lpfc_send_els_failure_event(struct lpfc_hba *phba,
+                       struct lpfc_iocbq *cmdiocbp,
+                       struct lpfc_iocbq *rspiocbp)
+{
+       struct lpfc_vport *vport = cmdiocbp->vport;
+       struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
+       struct lpfc_lsrjt_event lsrjt_event;
+       struct lpfc_fabric_event_header fabric_event;
+       struct ls_rjt stat;
+       struct lpfc_nodelist *ndlp;
+       uint32_t *pcmd;
+
+       ndlp = cmdiocbp->context1;
+       if (!ndlp || !NLP_CHK_NODE_ACT(ndlp))
+               return;
+
+       if (rspiocbp->iocb.ulpStatus == IOSTAT_LS_RJT) {
+               lsrjt_event.header.event_type = FC_REG_ELS_EVENT;
+               lsrjt_event.header.subcategory = LPFC_EVENT_LSRJT_RCV;
+               memcpy(lsrjt_event.header.wwpn, &ndlp->nlp_portname,
+                       sizeof(struct lpfc_name));
+               memcpy(lsrjt_event.header.wwnn, &ndlp->nlp_nodename,
+                       sizeof(struct lpfc_name));
+               pcmd = (uint32_t *) (((struct lpfc_dmabuf *)
+                       cmdiocbp->context2)->virt);
+               lsrjt_event.command = *pcmd;
+               stat.un.lsRjtError = be32_to_cpu(rspiocbp->iocb.un.ulpWord[4]);
+               lsrjt_event.reason_code = stat.un.b.lsRjtRsnCode;
+               lsrjt_event.explanation = stat.un.b.lsRjtRsnCodeExp;
+               fc_host_post_vendor_event(shost,
+                       fc_get_event_number(),
+                       sizeof(lsrjt_event),
+                       (char *)&lsrjt_event,
+                       LPFC_NL_VENDOR_ID);
+               return;
+       }
+       if ((rspiocbp->iocb.ulpStatus == IOSTAT_NPORT_BSY) ||
+               (rspiocbp->iocb.ulpStatus == IOSTAT_FABRIC_BSY)) {
+               fabric_event.event_type = FC_REG_FABRIC_EVENT;
+               if (rspiocbp->iocb.ulpStatus == IOSTAT_NPORT_BSY)
+                       fabric_event.subcategory = LPFC_EVENT_PORT_BUSY;
+               else
+                       fabric_event.subcategory = LPFC_EVENT_FABRIC_BUSY;
+               memcpy(fabric_event.wwpn, &ndlp->nlp_portname,
+                       sizeof(struct lpfc_name));
+               memcpy(fabric_event.wwnn, &ndlp->nlp_nodename,
+                       sizeof(struct lpfc_name));
+               fc_host_post_vendor_event(shost,
+                       fc_get_event_number(),
+                       sizeof(fabric_event),
+                       (char *)&fabric_event,
+                       LPFC_NL_VENDOR_ID);
+               return;
+       }
+
+}
+
+/**
+ * lpfc_send_els_event - Posts unsolicited els event
+ * @vport: Pointer to vport object.
+ * @ndlp: Pointer FC node object.
+ * @cmd: ELS command code.
+ *
+ * This function posts an event when there is an incoming
+ * unsolicited ELS command.
+ **/
+static void
+lpfc_send_els_event(struct lpfc_vport *vport,
+                   struct lpfc_nodelist *ndlp,
+                   uint32_t *payload)
+{
+       struct lpfc_els_event_header *els_data = NULL;
+       struct lpfc_logo_event *logo_data = NULL;
+       struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
+
+       if (*payload == ELS_CMD_LOGO) {
+               logo_data = kmalloc(sizeof(struct lpfc_logo_event), GFP_KERNEL);
+               if (!logo_data) {
+                       lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                               "0148 Failed to allocate memory "
+                               "for LOGO event\n");
+                       return;
+               }
+               els_data = &logo_data->header;
+       } else {
+               els_data = kmalloc(sizeof(struct lpfc_els_event_header),
+                       GFP_KERNEL);
+               if (!els_data) {
+                       lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                               "0149 Failed to allocate memory "
+                               "for ELS event\n");
+                       return;
                }
        }
+       els_data->event_type = FC_REG_ELS_EVENT;
+       switch (*payload) {
+       case ELS_CMD_PLOGI:
+               els_data->subcategory = LPFC_EVENT_PLOGI_RCV;
+               break;
+       case ELS_CMD_PRLO:
+               els_data->subcategory = LPFC_EVENT_PRLO_RCV;
+               break;
+       case ELS_CMD_ADISC:
+               els_data->subcategory = LPFC_EVENT_ADISC_RCV;
+               break;
+       case ELS_CMD_LOGO:
+               els_data->subcategory = LPFC_EVENT_LOGO_RCV;
+               /* Copy the WWPN in the LOGO payload */
+               memcpy(logo_data->logo_wwpn, &payload[2],
+                       sizeof(struct lpfc_name));
+               break;
+       default:
+               kfree(els_data);
+               return;
+       }
+       memcpy(els_data->wwpn, &ndlp->nlp_portname, sizeof(struct lpfc_name));
+       memcpy(els_data->wwnn, &ndlp->nlp_nodename, sizeof(struct lpfc_name));
+       if (*payload == ELS_CMD_LOGO) {
+               fc_host_post_vendor_event(shost,
+                       fc_get_event_number(),
+                       sizeof(struct lpfc_logo_event),
+                       (char *)logo_data,
+                       LPFC_NL_VENDOR_ID);
+               kfree(logo_data);
+       } else {
+               fc_host_post_vendor_event(shost,
+                       fc_get_event_number(),
+                       sizeof(struct lpfc_els_event_header),
+                       (char *)els_data,
+                       LPFC_NL_VENDOR_ID);
+               kfree(els_data);
+       }
+
        return;
 }
 
+
+/**
+ * lpfc_els_unsol_buffer - Process an unsolicited event data buffer
+ * @phba: pointer to lpfc hba data structure.
+ * @pring: pointer to a SLI ring.
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @elsiocb: pointer to lpfc els command iocb data structure.
+ *
+ * This routine is used for processing the IOCB associated with a unsolicited
+ * event. It first determines whether there is an existing ndlp that matches
+ * the DID from the unsolicited IOCB. If not, it will create a new one with
+ * the DID from the unsolicited IOCB. The ELS command from the unsolicited
+ * IOCB is then used to invoke the proper routine and to set up proper state
+ * of the discovery state machine.
+ **/
 static void
 lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                      struct lpfc_vport *vport, struct lpfc_iocbq *elsiocb)
@@ -3864,14 +5428,14 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
        uint32_t cmd, did, newnode, rjt_err = 0;
        IOCB_t *icmd = &elsiocb->iocb;
 
-       if (vport == NULL || elsiocb->context2 == NULL)
+       if (!vport || !(elsiocb->context2))
                goto dropit;
 
        newnode = 0;
        payload = ((struct lpfc_dmabuf *)elsiocb->context2)->virt;
        cmd = *payload;
        if ((phba->sli3_options & LPFC_SLI3_HBQ_ENABLED) == 0)
-               lpfc_post_buffer(phba, pring, 1, 1);
+               lpfc_post_buffer(phba, pring, 1);
 
        did = icmd->un.rcvels.remoteID;
        if (icmd->ulpStatus) {
@@ -3885,7 +5449,7 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
        if (lpfc_els_chk_latt(vport))
                goto dropit;
 
-       /* Ignore traffic recevied during vport shutdown. */
+       /* Ignore traffic received during vport shutdown. */
        if (vport->load_flag & FC_UNLOADING)
                goto dropit;
 
@@ -3899,22 +5463,28 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                lpfc_nlp_init(vport, ndlp, did);
                lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
                newnode = 1;
-               if ((did & Fabric_DID_MASK) == Fabric_DID_MASK) {
+               if ((did & Fabric_DID_MASK) == Fabric_DID_MASK)
                        ndlp->nlp_type |= NLP_FABRIC;
-               }
-       }
-       else {
-               if (ndlp->nlp_state == NLP_STE_UNUSED_NODE) {
-                       /* This is simular to the new node path */
-                       lpfc_nlp_get(ndlp);
-                       lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
-                       newnode = 1;
-               }
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               ndlp = lpfc_enable_node(vport, ndlp,
+                                       NLP_STE_UNUSED_NODE);
+               if (!ndlp)
+                       goto dropit;
+               lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
+               newnode = 1;
+               if ((did & Fabric_DID_MASK) == Fabric_DID_MASK)
+                       ndlp->nlp_type |= NLP_FABRIC;
+       } else if (ndlp->nlp_state == NLP_STE_UNUSED_NODE) {
+               /* This is similar to the new node path */
+               ndlp = lpfc_nlp_get(ndlp);
+               if (!ndlp)
+                       goto dropit;
+               lpfc_nlp_set_state(vport, ndlp, NLP_STE_NPR_NODE);
+               newnode = 1;
        }
 
        phba->fc_stat.elsRcvFrame++;
-       if (elsiocb->context1)
-               lpfc_nlp_put(elsiocb->context1);
+
        elsiocb->context1 = lpfc_nlp_get(ndlp);
        elsiocb->vport = vport;
 
@@ -3934,9 +5504,17 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                phba->fc_stat.elsRcvPLOGI++;
                ndlp = lpfc_plogi_confirm_nport(phba, payload, ndlp);
 
+               lpfc_send_els_event(vport, ndlp, payload);
                if (vport->port_state < LPFC_DISC_AUTH) {
-                       rjt_err = LSRJT_UNABLE_TPC;
-                       break;
+                       if (!(phba->pport->fc_flag & FC_PT2PT) ||
+                               (phba->pport->fc_flag & FC_PT2PT_PLOGI)) {
+                               rjt_err = LSRJT_UNABLE_TPC;
+                               break;
+                       }
+                       /* We get here, and drop thru, if we are PT2PT with
+                        * another NPort and the other side has initiated
+                        * the PLOGI before responding to our FLOGI.
+                        */
                }
 
                shost = lpfc_shost_from_vport(vport);
@@ -3964,6 +5542,7 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                        did, vport->port_state, ndlp->nlp_flag);
 
                phba->fc_stat.elsRcvLOGO++;
+               lpfc_send_els_event(vport, ndlp, payload);
                if (vport->port_state < LPFC_DISC_AUTH) {
                        rjt_err = LSRJT_UNABLE_TPC;
                        break;
@@ -3976,6 +5555,7 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                        did, vport->port_state, ndlp->nlp_flag);
 
                phba->fc_stat.elsRcvPRLO++;
+               lpfc_send_els_event(vport, ndlp, payload);
                if (vport->port_state < LPFC_DISC_AUTH) {
                        rjt_err = LSRJT_UNABLE_TPC;
                        break;
@@ -3993,6 +5573,7 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                        "RCV ADISC:       did:x%x/ste:x%x flg:x%x",
                        did, vport->port_state, ndlp->nlp_flag);
 
+               lpfc_send_els_event(vport, ndlp, payload);
                phba->fc_stat.elsRcvADISC++;
                if (vport->port_state < LPFC_DISC_AUTH) {
                        rjt_err = LSRJT_UNABLE_TPC;
@@ -4090,6 +5671,16 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                if (newnode)
                        lpfc_nlp_put(ndlp);
                break;
+       case ELS_CMD_RRQ:
+               lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_ELS_UNSOL,
+                       "RCV RRQ:         did:x%x/ste:x%x flg:x%x",
+                       did, vport->port_state, ndlp->nlp_flag);
+
+               phba->fc_stat.elsRcvRRQ++;
+               lpfc_els_rcv_rrq(vport, elsiocb, ndlp);
+               if (newnode)
+                       lpfc_nlp_put(ndlp);
+               break;
        default:
                lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_ELS_UNSOL,
                        "RCV ELS cmd:     cmd:x%x did:x%x/ste:x%x",
@@ -4116,19 +5707,33 @@ lpfc_els_unsol_buffer(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                        NULL);
        }
 
+       lpfc_nlp_put(elsiocb->context1);
+       elsiocb->context1 = NULL;
        return;
 
 dropit:
        if (vport && !(vport->load_flag & FC_UNLOADING))
-               lpfc_printf_log(phba, KERN_ERR, LOG_ELS,
-                       "(%d):0111 Dropping received ELS cmd "
+               lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                       "0111 Dropping received ELS cmd "
                        "Data: x%x x%x x%x\n",
-                       vport->vpi, icmd->ulpStatus,
-                       icmd->un.ulpWord[4], icmd->ulpTimeout);
+                       icmd->ulpStatus, icmd->un.ulpWord[4], icmd->ulpTimeout);
        phba->fc_stat.elsRcvDrop++;
 }
 
-static struct lpfc_vport *
+/**
+ * lpfc_find_vport_by_vpid - Find a vport on a HBA through vport identifier
+ * @phba: pointer to lpfc hba data structure.
+ * @vpi: host virtual N_Port identifier.
+ *
+ * This routine finds a vport on a HBA (referred by @phba) through a
+ * @vpi. The function walks the HBA's vport list and returns the address
+ * of the vport with the matching @vpi.
+ *
+ * Return code
+ *    NULL - No vport with the matching @vpi found
+ *    Otherwise - Address to the vport with the matching @vpi.
+ **/
+struct lpfc_vport *
 lpfc_find_vport_by_vpid(struct lpfc_hba *phba, uint16_t vpi)
 {
        struct lpfc_vport *vport;
@@ -4145,6 +5750,18 @@ lpfc_find_vport_by_vpid(struct lpfc_hba *phba, uint16_t vpi)
        return NULL;
 }
 
+/**
+ * lpfc_els_unsol_event - Process an unsolicited event from an els sli ring
+ * @phba: pointer to lpfc hba data structure.
+ * @pring: pointer to a SLI ring.
+ * @elsiocb: pointer to lpfc els iocb data structure.
+ *
+ * This routine is used to process an unsolicited event received from a SLI
+ * (Service Level Interface) ring. The actual processing of the data buffer
+ * associated with the unsolicited event is done by invoking the routine
+ * lpfc_els_unsol_buffer() after properly set up the iocb buffer from the
+ * SLI ring on which the unsolicited event was received.
+ **/
 void
 lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                     struct lpfc_iocbq *elsiocb)
@@ -4155,6 +5772,7 @@ lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
        struct lpfc_dmabuf *bdeBuf1 = elsiocb->context2;
        struct lpfc_dmabuf *bdeBuf2 = elsiocb->context3;
 
+       elsiocb->context1 = NULL;
        elsiocb->context2 = NULL;
        elsiocb->context3 = NULL;
 
@@ -4165,7 +5783,7 @@ lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
                phba->fc_stat.NoRcvBuf++;
                /* Not enough posted buffers; Try posting more buffers */
                if (!(phba->sli3_options & LPFC_SLI3_HBQ_ENABLED))
-                       lpfc_post_buffer(phba, pring, 0, 1);
+                       lpfc_post_buffer(phba, pring, 0);
                return;
        }
 
@@ -4174,20 +5792,19 @@ lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
             icmd->ulpCommand == CMD_IOCB_RCV_SEQ64_CX)) {
                if (icmd->unsli3.rcvsli3.vpi == 0xffff)
                        vport = phba->pport;
-               else {
-                       uint16_t vpi = icmd->unsli3.rcvsli3.vpi;
-                       vport = lpfc_find_vport_by_vpid(phba, vpi);
-               }
+               else
+                       vport = lpfc_find_vport_by_vpid(phba,
+                               icmd->unsli3.rcvsli3.vpi - phba->vpi_base);
        }
-                               /* If there are no BDEs associated
-                                * with this IOCB, there is nothing to do.
-                                */
+       /* If there are no BDEs associated
+        * with this IOCB, there is nothing to do.
+        */
        if (icmd->ulpBdeCount == 0)
                return;
 
-                               /* type of ELS cmd is first 32bit word
-                                * in packet
-                                */
+       /* type of ELS cmd is first 32bit word
+        * in packet
+        */
        if (phba->sli3_options & LPFC_SLI3_HBQ_ENABLED) {
                elsiocb->context2 = bdeBuf1;
        } else {
@@ -4202,8 +5819,6 @@ lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
         * The different unsolicited event handlers would tell us
         * if they are done with "mp" by setting context2 to NULL.
         */
-       lpfc_nlp_put(elsiocb->context1);
-       elsiocb->context1 = NULL;
        if (elsiocb->context2) {
                lpfc_in_buf_free(phba, (struct lpfc_dmabuf *)elsiocb->context2);
                elsiocb->context2 = NULL;
@@ -4222,6 +5837,19 @@ lpfc_els_unsol_event(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
        }
 }
 
+/**
+ * lpfc_do_scr_ns_plogi - Issue a plogi to the name server for scr
+ * @phba: pointer to lpfc hba data structure.
+ * @vport: pointer to a virtual N_Port data structure.
+ *
+ * This routine issues a Port Login (PLOGI) to the Name Server with
+ * State Change Request (SCR) for a @vport. This routine will create an
+ * ndlp for the Name Server associated to the @vport if such node does
+ * not already exist. The PLOGI to Name Server is issued by invoking the
+ * lpfc_issue_els_plogi() routine. If Fabric-Device Management Interface
+ * (FDMI) is configured to the @vport, a FDMI node will be created and
+ * the PLOGI to FDMI is issued by invoking lpfc_issue_els_plogi() routine.
+ **/
 void
 lpfc_do_scr_ns_plogi(struct lpfc_hba *phba, struct lpfc_vport *vport)
 {
@@ -4241,8 +5869,20 @@ lpfc_do_scr_ns_plogi(struct lpfc_hba *phba, struct lpfc_vport *vport)
                        return;
                }
                lpfc_nlp_init(vport, ndlp, NameServer_DID);
-               ndlp->nlp_type |= NLP_FABRIC;
+       } else if (!NLP_CHK_NODE_ACT(ndlp)) {
+               ndlp = lpfc_enable_node(vport, ndlp, NLP_STE_UNUSED_NODE);
+               if (!ndlp) {
+                       if (phba->fc_topology == TOPOLOGY_LOOP) {
+                               lpfc_disc_start(vport);
+                               return;
+                       }
+                       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+                       lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
+                                       "0348 NameServer login: node freed\n");
+                       return;
+               }
        }
+       ndlp->nlp_type |= NLP_FABRIC;
 
        lpfc_nlp_set_state(vport, ndlp, NLP_STE_PLOGI_ISSUE);
 
@@ -4259,8 +5899,8 @@ lpfc_do_scr_ns_plogi(struct lpfc_hba *phba, struct lpfc_vport *vport)
                if (ndlp_fdmi) {
                        lpfc_nlp_init(vport, ndlp_fdmi, FDMI_DID);
                        ndlp_fdmi->nlp_type |= NLP_FABRIC;
-                       ndlp_fdmi->nlp_state =
-                               NLP_STE_PLOGI_ISSUE;
+                       lpfc_nlp_set_state(vport, ndlp_fdmi,
+                               NLP_STE_PLOGI_ISSUE);
                        lpfc_issue_els_plogi(vport, ndlp_fdmi->nlp_DID,
                                             0);
                }
@@ -4268,16 +5908,30 @@ lpfc_do_scr_ns_plogi(struct lpfc_hba *phba, struct lpfc_vport *vport)
        return;
 }
 
+/**
+ * lpfc_cmpl_reg_new_vport - Completion callback function to register new vport
+ * @phba: pointer to lpfc hba data structure.
+ * @pmb: pointer to the driver internal queue element for mailbox command.
+ *
+ * This routine is the completion callback function to register new vport
+ * mailbox command. If the new vport mailbox command completes successfully,
+ * the fabric registration login shall be performed on physical port (the
+ * new vport created is actually a physical port, with VPI 0) or the port
+ * login to Name Server for State Change Request (SCR) will be performed
+ * on virtual port (real virtual port, with VPI greater than 0).
+ **/
 static void
 lpfc_cmpl_reg_new_vport(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 {
        struct lpfc_vport *vport = pmb->vport;
        struct Scsi_Host  *shost = lpfc_shost_from_vport(vport);
        struct lpfc_nodelist *ndlp = (struct lpfc_nodelist *) pmb->context2;
-       MAILBOX_t *mb = &pmb->mb;
+       MAILBOX_t *mb = &pmb->u.mb;
+       int rc;
 
+       spin_lock_irq(shost->host_lock);
        vport->fc_flag &= ~FC_VPORT_NEEDS_REG_VPI;
-       lpfc_nlp_put(ndlp);
+       spin_unlock_irq(shost->host_lock);
 
        if (mb->mbxStatus) {
                lpfc_printf_vlog(vport, KERN_ERR, LOG_MBOX,
@@ -4287,6 +5941,7 @@ lpfc_cmpl_reg_new_vport(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
                switch (mb->mbxStatus) {
                case 0x11:      /* unsupported feature */
                case 0x9603:    /* max_vpi exceeded */
+               case 0x9602:    /* Link event since CLEAR_LA */
                        /* giving up on vport registration */
                        lpfc_vport_set_state(vport, FC_VPORT_FAILED);
                        spin_lock_irq(shost->host_lock);
@@ -4294,56 +5949,203 @@ lpfc_cmpl_reg_new_vport(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
                        spin_unlock_irq(shost->host_lock);
                        lpfc_can_disctmo(vport);
                        break;
+               /* If reg_vpi fail with invalid VPI status, re-init VPI */
+               case 0x20:
+                       spin_lock_irq(shost->host_lock);
+                       vport->fc_flag |= FC_VPORT_NEEDS_REG_VPI;
+                       spin_unlock_irq(shost->host_lock);
+                       lpfc_init_vpi(phba, pmb, vport->vpi);
+                       pmb->vport = vport;
+                       pmb->mbox_cmpl = lpfc_init_vpi_cmpl;
+                       rc = lpfc_sli_issue_mbox(phba, pmb,
+                               MBX_NOWAIT);
+                       if (rc == MBX_NOT_FINISHED) {
+                               lpfc_printf_vlog(vport,
+                                       KERN_ERR, LOG_MBOX,
+                                       "2732 Failed to issue INIT_VPI"
+                                       " mailbox command\n");
+                       } else {
+                               lpfc_nlp_put(ndlp);
+                               return;
+                       }
+
                default:
                        /* Try to recover from this error */
                        lpfc_mbx_unreg_vpi(vport);
+                       spin_lock_irq(shost->host_lock);
                        vport->fc_flag |= FC_VPORT_NEEDS_REG_VPI;
-                       lpfc_initial_fdisc(vport);
+                       spin_unlock_irq(shost->host_lock);
+                       if (vport->port_type == LPFC_PHYSICAL_PORT)
+                               lpfc_initial_flogi(vport);
+                       else
+                               lpfc_initial_fdisc(vport);
                        break;
                }
-
        } else {
-               if (vport == phba->pport)
-                       lpfc_issue_fabric_reglogin(vport);
-               else
+               spin_lock_irq(shost->host_lock);
+               vport->vpi_state |= LPFC_VPI_REGISTERED;
+               spin_unlock_irq(shost->host_lock);
+               if (vport == phba->pport) {
+                       if (phba->sli_rev < LPFC_SLI_REV4)
+                               lpfc_issue_fabric_reglogin(vport);
+                       else {
+                               lpfc_start_fdiscs(phba);
+                               lpfc_do_scr_ns_plogi(phba, vport);
+                       }
+               } else
                        lpfc_do_scr_ns_plogi(phba, vport);
        }
+
+       /* Now, we decrement the ndlp reference count held for this
+        * callback function
+        */
+       lpfc_nlp_put(ndlp);
+
        mempool_free(pmb, phba->mbox_mem_pool);
        return;
 }
 
-static void
+/**
+ * lpfc_register_new_vport - Register a new vport with a HBA
+ * @phba: pointer to lpfc hba data structure.
+ * @vport: pointer to a host virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine registers the @vport as a new virtual port with a HBA.
+ * It is done through a registering vpi mailbox command.
+ **/
+void
 lpfc_register_new_vport(struct lpfc_hba *phba, struct lpfc_vport *vport,
                        struct lpfc_nodelist *ndlp)
 {
+       struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
        LPFC_MBOXQ_t *mbox;
 
        mbox = mempool_alloc(phba->mbox_mem_pool, GFP_KERNEL);
        if (mbox) {
-               lpfc_reg_vpi(phba, vport->vpi, vport->fc_myDID, mbox);
+               lpfc_reg_vpi(vport, mbox);
                mbox->vport = vport;
                mbox->context2 = lpfc_nlp_get(ndlp);
                mbox->mbox_cmpl = lpfc_cmpl_reg_new_vport;
                if (lpfc_sli_issue_mbox(phba, mbox, MBX_NOWAIT)
                    == MBX_NOT_FINISHED) {
+                       /* mailbox command not success, decrement ndlp
+                        * reference count for this command
+                        */
+                       lpfc_nlp_put(ndlp);
                        mempool_free(mbox, phba->mbox_mem_pool);
-                       vport->fc_flag &= ~FC_VPORT_NEEDS_REG_VPI;
 
-                       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
                        lpfc_printf_vlog(vport, KERN_ERR, LOG_MBOX,
                                "0253 Register VPI: Can't send mbox\n");
+                       goto mbox_err_exit;
                }
        } else {
-               lpfc_vport_set_state(vport, FC_VPORT_FAILED);
-
                lpfc_printf_vlog(vport, KERN_ERR, LOG_MBOX,
                                 "0254 Register VPI: no memory\n");
+               goto mbox_err_exit;
+       }
+       return;
 
-               vport->fc_flag &= ~FC_VPORT_NEEDS_REG_VPI;
-               lpfc_nlp_put(ndlp);
+mbox_err_exit:
+       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+       spin_lock_irq(shost->host_lock);
+       vport->fc_flag &= ~FC_VPORT_NEEDS_REG_VPI;
+       spin_unlock_irq(shost->host_lock);
+       return;
+}
+
+/**
+ * lpfc_retry_pport_discovery - Start timer to retry FLOGI.
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine abort all pending discovery commands and
+ * start a timer to retry FLOGI for the physical port
+ * discovery.
+ **/
+void
+lpfc_retry_pport_discovery(struct lpfc_hba *phba)
+{
+       struct lpfc_vport **vports;
+       struct lpfc_nodelist *ndlp;
+       struct Scsi_Host  *shost;
+       int i;
+       uint32_t link_state;
+
+       /* Treat this failure as linkdown for all vports */
+       link_state = phba->link_state;
+       lpfc_linkdown(phba);
+       phba->link_state = link_state;
+
+       vports = lpfc_create_vport_work_array(phba);
+
+       if (vports) {
+               for (i = 0; i <= phba->max_vports && vports[i] != NULL; i++) {
+                       ndlp = lpfc_findnode_did(vports[i], Fabric_DID);
+                       if (ndlp)
+                               lpfc_cancel_retry_delay_tmo(vports[i], ndlp);
+                       lpfc_els_flush_cmd(vports[i]);
+               }
+               lpfc_destroy_vport_work_array(phba, vports);
        }
+
+       /* If fabric require FLOGI, then re-instantiate physical login */
+       ndlp = lpfc_findnode_did(phba->pport, Fabric_DID);
+       if (!ndlp)
+               return;
+
+
+       shost = lpfc_shost_from_vport(phba->pport);
+       mod_timer(&ndlp->nlp_delayfunc, jiffies + HZ);
+       spin_lock_irq(shost->host_lock);
+       ndlp->nlp_flag |= NLP_DELAY_TMO;
+       spin_unlock_irq(shost->host_lock);
+       ndlp->nlp_last_elscmd = ELS_CMD_FLOGI;
+       phba->pport->port_state = LPFC_FLOGI;
+       return;
+}
+
+/**
+ * lpfc_fabric_login_reqd - Check if FLOGI required.
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to FDISC command iocb.
+ * @rspiocb: pointer to FDISC response iocb.
+ *
+ * This routine checks if a FLOGI is reguired for FDISC
+ * to succeed.
+ **/
+static int
+lpfc_fabric_login_reqd(struct lpfc_hba *phba,
+               struct lpfc_iocbq *cmdiocb,
+               struct lpfc_iocbq *rspiocb)
+{
+
+       if ((rspiocb->iocb.ulpStatus != IOSTAT_FABRIC_RJT) ||
+               (rspiocb->iocb.un.ulpWord[4] != RJT_LOGIN_REQUIRED))
+               return 0;
+       else
+               return 1;
 }
 
+/**
+ * lpfc_cmpl_els_fdisc - Completion function for fdisc iocb command
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function to a Fabric Discover
+ * (FDISC) ELS command. Since all the FDISC ELS commands are issued
+ * single threaded, each FDISC completion callback function will reset
+ * the discovery timer for all vports such that the timers will not get
+ * unnecessary timeout. The function checks the FDISC IOCB status. If error
+ * detected, the vport will be set to FC_VPORT_FAILED state. Otherwise,the
+ * vport will set to FC_VPORT_ACTIVE state. It then checks whether the DID
+ * assigned to the vport has been changed with the completion of the FDISC
+ * command. If so, both RPI (Remote Port Index) and VPI (Virtual Port Index)
+ * are unregistered from the HBA, and then the lpfc_register_new_vport()
+ * routine is invoked to register new vport with the HBA. Otherwise, the
+ * lpfc_do_scr_ns_plogi() routine is invoked to issue a PLOGI to the Name
+ * Server for State Change Request (SCR).
+ **/
 static void
 lpfc_cmpl_els_fdisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                    struct lpfc_iocbq *rspiocb)
@@ -4373,60 +6175,90 @@ lpfc_cmpl_els_fdisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                irsp->ulpStatus, irsp->un.ulpWord[4], vport->fc_prevDID);
 
        if (irsp->ulpStatus) {
+
+               if (lpfc_fabric_login_reqd(phba, cmdiocb, rspiocb)) {
+                       lpfc_retry_pport_discovery(phba);
+                       goto out;
+               }
+
                /* Check for retry */
                if (lpfc_els_retry(phba, cmdiocb, rspiocb))
                        goto out;
                /* FDISC failed */
                lpfc_printf_vlog(vport, KERN_ERR, LOG_ELS,
-                                "0124 FDISC failed. (%d/%d)\n",
+                                "0126 FDISC failed. (%d/%d)\n",
                                 irsp->ulpStatus, irsp->un.ulpWord[4]);
-               if (vport->fc_vport->vport_state == FC_VPORT_INITIALIZING)
-                       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+               goto fdisc_failed;
+       }
+       spin_lock_irq(shost->host_lock);
+       vport->fc_flag &= ~FC_VPORT_CVL_RCVD;
+       vport->fc_flag |= FC_FABRIC;
+       if (vport->phba->fc_topology == TOPOLOGY_LOOP)
+               vport->fc_flag |=  FC_PUBLIC_LOOP;
+       spin_unlock_irq(shost->host_lock);
 
-               lpfc_nlp_put(ndlp);
-               /* giving up on FDISC. Cancel discovery timer */
-               lpfc_can_disctmo(vport);
-       } else {
+       vport->fc_myDID = irsp->un.ulpWord[4] & Mask_DID;
+       lpfc_vport_set_state(vport, FC_VPORT_ACTIVE);
+       if ((vport->fc_prevDID != vport->fc_myDID) &&
+               !(vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)) {
+               /* If our NportID changed, we need to ensure all
+                * remaining NPORTs get unreg_login'ed so we can
+                * issue unreg_vpi.
+                */
+               list_for_each_entry_safe(np, next_np,
+                       &vport->fc_nodes, nlp_listp) {
+                       if (!NLP_CHK_NODE_ACT(ndlp) ||
+                           (np->nlp_state != NLP_STE_NPR_NODE) ||
+                           !(np->nlp_flag & NLP_NPR_ADISC))
+                               continue;
+                       spin_lock_irq(shost->host_lock);
+                       np->nlp_flag &= ~NLP_NPR_ADISC;
+                       spin_unlock_irq(shost->host_lock);
+                       lpfc_unreg_rpi(vport, np);
+               }
+               lpfc_mbx_unreg_vpi(vport);
                spin_lock_irq(shost->host_lock);
-               vport->fc_flag |= FC_FABRIC;
-               if (vport->phba->fc_topology == TOPOLOGY_LOOP)
-                       vport->fc_flag |=  FC_PUBLIC_LOOP;
+               vport->fc_flag |= FC_VPORT_NEEDS_REG_VPI;
+               vport->fc_flag |= FC_VPORT_NEEDS_INIT_VPI;
                spin_unlock_irq(shost->host_lock);
-
-               vport->fc_myDID = irsp->un.ulpWord[4] & Mask_DID;
-               lpfc_vport_set_state(vport, FC_VPORT_ACTIVE);
-               if ((vport->fc_prevDID != vport->fc_myDID) &&
-                       !(vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)) {
-                       /* If our NportID changed, we need to ensure all
-                        * remaining NPORTs get unreg_login'ed so we can
-                        * issue unreg_vpi.
-                        */
-                       list_for_each_entry_safe(np, next_np,
-                               &vport->fc_nodes, nlp_listp) {
-                               if (np->nlp_state != NLP_STE_NPR_NODE
-                                  || !(np->nlp_flag & NLP_NPR_ADISC))
-                                       continue;
-                               spin_lock_irq(shost->host_lock);
-                               np->nlp_flag &= ~NLP_NPR_ADISC;
-                               spin_unlock_irq(shost->host_lock);
-                               lpfc_unreg_rpi(vport, np);
-                       }
-                       lpfc_mbx_unreg_vpi(vport);
-                       vport->fc_flag |= FC_VPORT_NEEDS_REG_VPI;
-               }
-
-               if (vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)
-                       lpfc_register_new_vport(phba, vport, ndlp);
-               else
-                       lpfc_do_scr_ns_plogi(phba, vport);
-
-               lpfc_nlp_put(ndlp); /* Free Fabric ndlp for vports */
        }
 
+       if (vport->fc_flag & FC_VPORT_NEEDS_INIT_VPI)
+               lpfc_issue_init_vpi(vport);
+       else if (vport->fc_flag & FC_VPORT_NEEDS_REG_VPI)
+               lpfc_register_new_vport(phba, vport, ndlp);
+       else
+               lpfc_do_scr_ns_plogi(phba, vport);
+       goto out;
+fdisc_failed:
+       lpfc_vport_set_state(vport, FC_VPORT_FAILED);
+       /* Cancel discovery timer */
+       lpfc_can_disctmo(vport);
+       lpfc_nlp_put(ndlp);
 out:
        lpfc_els_free_iocb(phba, cmdiocb);
 }
 
+/**
+ * lpfc_issue_els_fdisc - Issue a fdisc iocb command
+ * @vport: pointer to a virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ * @retry: number of retries to the command IOCB.
+ *
+ * This routine prepares and issues a Fabric Discover (FDISC) IOCB to
+ * a remote node (@ndlp) off a @vport. It uses the lpfc_issue_fabric_iocb()
+ * routine to issue the IOCB, which makes sure only one outstanding fabric
+ * IOCB will be sent off HBA at any given time.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the FDISC ELS command.
+ *
+ * Return code
+ *   0 - Successfully issued fdisc iocb command
+ *   1 - Failed to issue fdisc iocb command
+ **/
 static int
 lpfc_issue_els_fdisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                     uint8_t retry)
@@ -4440,6 +6272,7 @@ lpfc_issue_els_fdisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        int did = ndlp->nlp_DID;
        int rc;
 
+       vport->port_state = LPFC_FDISC;
        cmdsize = (sizeof(uint32_t) + sizeof(struct serv_parm));
        elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp, did,
                                     ELS_CMD_FDISC);
@@ -4454,9 +6287,17 @@ lpfc_issue_els_fdisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
        icmd->un.elsreq64.myID = 0;
        icmd->un.elsreq64.fl = 1;
 
-       /* For FDISC, Let FDISC rsp set the NPortID for this VPI */
-       icmd->ulpCt_h = 1;
-       icmd->ulpCt_l = 0;
+       if  (phba->sli_rev == LPFC_SLI_REV4) {
+               /* FDISC needs to be 1 for WQE VPI */
+               elsiocb->iocb.ulpCt_h = (SLI4_CT_VPI >> 1) & 1;
+               elsiocb->iocb.ulpCt_l = SLI4_CT_VPI & 1 ;
+               /* Set the ulpContext to the vpi */
+               elsiocb->iocb.ulpContext = vport->vpi + phba->vpi_base;
+       } else {
+               /* For FDISC, Let FDISC rsp set the NPortID for this VPI */
+               icmd->ulpCt_h = 1;
+               icmd->ulpCt_l = 0;
+       }
 
        pcmd = (uint8_t *) (((struct lpfc_dmabuf *) elsiocb->context2)->virt);
        *((uint32_t *) (pcmd)) = ELS_CMD_FDISC;
@@ -4497,16 +6338,31 @@ lpfc_issue_els_fdisc(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
                return 1;
        }
        lpfc_vport_set_state(vport, FC_VPORT_INITIALIZING);
-       vport->port_state = LPFC_FDISC;
        return 0;
 }
 
+/**
+ * lpfc_cmpl_els_npiv_logo - Completion function with vport logo
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the completion callback function to the issuing of a LOGO
+ * ELS command off a vport. It frees the command IOCB and then decrement the
+ * reference count held on ndlp for this completion function, indicating that
+ * the reference to the ndlp is no long needed. Note that the
+ * lpfc_els_free_iocb() routine decrements the ndlp reference held for this
+ * callback function and an additional explicit ndlp reference decrementation
+ * will trigger the actual release of the ndlp.
+ **/
 static void
 lpfc_cmpl_els_npiv_logo(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                        struct lpfc_iocbq *rspiocb)
 {
        struct lpfc_vport *vport = cmdiocb->vport;
        IOCB_t *irsp;
+       struct lpfc_nodelist *ndlp;
+       ndlp = (struct lpfc_nodelist *)cmdiocb->context1;
 
        irsp = &rspiocb->iocb;
        lpfc_debugfs_disc_trc(vport, LPFC_DISC_TRC_ELS_CMD,
@@ -4515,14 +6371,32 @@ lpfc_cmpl_els_npiv_logo(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 
        lpfc_els_free_iocb(phba, cmdiocb);
        vport->unreg_vpi_cmpl = VPORT_ERROR;
+
+       /* Trigger the release of the ndlp after logo */
+       lpfc_nlp_put(ndlp);
 }
 
+/**
+ * lpfc_issue_els_npiv_logo - Issue a logo off a vport
+ * @vport: pointer to a virtual N_Port data structure.
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine issues a LOGO ELS command to an @ndlp off a @vport.
+ *
+ * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp
+ * will be incremented by 1 for holding the ndlp and the reference to ndlp
+ * will be stored into the context1 field of the IOCB for the completion
+ * callback function to the LOGO ELS command.
+ *
+ * Return codes
+ *   0 - Successfully issued logo off the @vport
+ *   1 - Failed to issue logo off the @vport
+ **/
 int
 lpfc_issue_els_npiv_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 {
        struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
        struct lpfc_hba  *phba = vport->phba;
-       struct lpfc_sli_ring *pring = &phba->sli.ring[LPFC_ELS_RING];
        IOCB_t *icmd;
        struct lpfc_iocbq *elsiocb;
        uint8_t *pcmd;
@@ -4552,7 +6426,8 @@ lpfc_issue_els_npiv_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
        spin_lock_irq(shost->host_lock);
        ndlp->nlp_flag |= NLP_LOGO_SND;
        spin_unlock_irq(shost->host_lock);
-       if (lpfc_sli_issue_iocb(phba, pring, elsiocb, 0) == IOCB_ERROR) {
+       if (lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, elsiocb, 0) ==
+           IOCB_ERROR) {
                spin_lock_irq(shost->host_lock);
                ndlp->nlp_flag &= ~NLP_LOGO_SND;
                spin_unlock_irq(shost->host_lock);
@@ -4562,43 +6437,62 @@ lpfc_issue_els_npiv_logo(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
        return 0;
 }
 
+/**
+ * lpfc_fabric_block_timeout - Handler function to the fabric block timer
+ * @ptr: holder for the timer function associated data.
+ *
+ * This routine is invoked by the fabric iocb block timer after
+ * timeout. It posts the fabric iocb block timeout event by setting the
+ * WORKER_FABRIC_BLOCK_TMO bit to work port event bitmap and then invokes
+ * lpfc_worker_wake_up() routine to wake up the worker thread. It is for
+ * the worker thread to invoke the lpfc_unblock_fabric_iocbs() on the
+ * posted event WORKER_FABRIC_BLOCK_TMO.
+ **/
 void
 lpfc_fabric_block_timeout(unsigned long ptr)
 {
        struct lpfc_hba  *phba = (struct lpfc_hba *) ptr;
        unsigned long iflags;
        uint32_t tmo_posted;
+
        spin_lock_irqsave(&phba->pport->work_port_lock, iflags);
        tmo_posted = phba->pport->work_port_events & WORKER_FABRIC_BLOCK_TMO;
        if (!tmo_posted)
                phba->pport->work_port_events |= WORKER_FABRIC_BLOCK_TMO;
        spin_unlock_irqrestore(&phba->pport->work_port_lock, iflags);
 
-       if (!tmo_posted) {
-               spin_lock_irqsave(&phba->hbalock, iflags);
-               if (phba->work_wait)
-                       lpfc_worker_wake_up(phba);
-               spin_unlock_irqrestore(&phba->hbalock, iflags);
-       }
+       if (!tmo_posted)
+               lpfc_worker_wake_up(phba);
+       return;
 }
 
+/**
+ * lpfc_resume_fabric_iocbs - Issue a fabric iocb from driver internal list
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine issues one fabric iocb from the driver internal list to
+ * the HBA. It first checks whether it's ready to issue one fabric iocb to
+ * the HBA (whether there is no outstanding fabric iocb). If so, it shall
+ * remove one pending fabric iocb from the driver internal list and invokes
+ * lpfc_sli_issue_iocb() routine to send the fabric iocb to the HBA.
+ **/
 static void
 lpfc_resume_fabric_iocbs(struct lpfc_hba *phba)
 {
        struct lpfc_iocbq *iocb;
        unsigned long iflags;
        int ret;
-       struct lpfc_sli_ring *pring = &phba->sli.ring[LPFC_ELS_RING];
        IOCB_t *cmd;
 
 repeat:
        iocb = NULL;
        spin_lock_irqsave(&phba->hbalock, iflags);
-                               /* Post any pending iocb to the SLI layer */
+       /* Post any pending iocb to the SLI layer */
        if (atomic_read(&phba->fabric_iocb_count) == 0) {
                list_remove_head(&phba->fabric_iocb_list, iocb, typeof(*iocb),
                                 list);
                if (iocb)
+                       /* Increment fabric iocb count to hold the position */
                        atomic_inc(&phba->fabric_iocb_count);
        }
        spin_unlock_irqrestore(&phba->hbalock, iflags);
@@ -4611,7 +6505,7 @@ repeat:
                        "Fabric sched1:   ste:x%x",
                        iocb->vport->port_state, 0, 0);
 
-               ret = lpfc_sli_issue_iocb(phba, pring, iocb, 0);
+               ret = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, iocb, 0);
 
                if (ret == IOCB_ERROR) {
                        iocb->iocb_cmpl = iocb->fabric_iocb_cmpl;
@@ -4630,6 +6524,15 @@ repeat:
        return;
 }
 
+/**
+ * lpfc_unblock_fabric_iocbs - Unblock issuing fabric iocb command
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine unblocks the  issuing fabric iocb command. The function
+ * will clear the fabric iocb block bit and then invoke the routine
+ * lpfc_resume_fabric_iocbs() to issue one of the pending fabric iocb
+ * from the driver internal fabric iocb list.
+ **/
 void
 lpfc_unblock_fabric_iocbs(struct lpfc_hba *phba)
 {
@@ -4639,21 +6542,41 @@ lpfc_unblock_fabric_iocbs(struct lpfc_hba *phba)
        return;
 }
 
+/**
+ * lpfc_block_fabric_iocbs - Block issuing fabric iocb command
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine blocks the issuing fabric iocb for a specified amount of
+ * time (currently 100 ms). This is done by set the fabric iocb block bit
+ * and set up a timeout timer for 100ms. When the block bit is set, no more
+ * fabric iocb will be issued out of the HBA.
+ **/
 static void
 lpfc_block_fabric_iocbs(struct lpfc_hba *phba)
 {
        int blocked;
 
        blocked = test_and_set_bit(FABRIC_COMANDS_BLOCKED, &phba->bit_flags);
-                               /* Start a timer to unblock fabric
-                                * iocbs after 100ms
-                                */
+       /* Start a timer to unblock fabric iocbs after 100ms */
        if (!blocked)
                mod_timer(&phba->fabric_block_timer, jiffies + HZ/10 );
 
        return;
 }
 
+/**
+ * lpfc_cmpl_fabric_iocb - Completion callback function for fabric iocb
+ * @phba: pointer to lpfc hba data structure.
+ * @cmdiocb: pointer to lpfc command iocb data structure.
+ * @rspiocb: pointer to lpfc response iocb data structure.
+ *
+ * This routine is the callback function that is put to the fabric iocb's
+ * callback function pointer (iocb->iocb_cmpl). The original iocb's callback
+ * function pointer has been stored in iocb->fabric_iocb_cmpl. This callback
+ * function first restores and invokes the original iocb's callback function
+ * and then invokes the lpfc_resume_fabric_iocbs() routine to issue the next
+ * fabric bound iocb from the driver internal fabric iocb list onto the wire.
+ **/
 static void
 lpfc_cmpl_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        struct lpfc_iocbq *rspiocb)
@@ -4695,16 +6618,39 @@ lpfc_cmpl_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 
        atomic_dec(&phba->fabric_iocb_count);
        if (!test_bit(FABRIC_COMANDS_BLOCKED, &phba->bit_flags)) {
-                               /* Post any pending iocbs to HBA */
-                   lpfc_resume_fabric_iocbs(phba);
+               /* Post any pending iocbs to HBA */
+               lpfc_resume_fabric_iocbs(phba);
        }
 }
 
+/**
+ * lpfc_issue_fabric_iocb - Issue a fabric iocb command
+ * @phba: pointer to lpfc hba data structure.
+ * @iocb: pointer to lpfc command iocb data structure.
+ *
+ * This routine is used as the top-level API for issuing a fabric iocb command
+ * such as FLOGI and FDISC. To accommodate certain switch fabric, this driver
+ * function makes sure that only one fabric bound iocb will be outstanding at
+ * any given time. As such, this function will first check to see whether there
+ * is already an outstanding fabric iocb on the wire. If so, it will put the
+ * newly issued iocb onto the driver internal fabric iocb list, waiting to be
+ * issued later. Otherwise, it will issue the iocb on the wire and update the
+ * fabric iocb count it indicate that there is one fabric iocb on the wire.
+ *
+ * Note, this implementation has a potential sending out fabric IOCBs out of
+ * order. The problem is caused by the construction of the "ready" boolen does
+ * not include the condition that the internal fabric IOCB list is empty. As
+ * such, it is possible a fabric IOCB issued by this routine might be "jump"
+ * ahead of the fabric IOCBs in the internal list.
+ *
+ * Return code
+ *   IOCB_SUCCESS - either fabric iocb put on the list or issued successfully
+ *   IOCB_ERROR - failed to issue fabric iocb
+ **/
 static int
 lpfc_issue_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *iocb)
 {
        unsigned long iflags;
-       struct lpfc_sli_ring *pring = &phba->sli.ring[LPFC_ELS_RING];
        int ready;
        int ret;
 
@@ -4715,6 +6661,9 @@ lpfc_issue_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *iocb)
        ready = atomic_read(&phba->fabric_iocb_count) == 0 &&
                !test_bit(FABRIC_COMANDS_BLOCKED, &phba->bit_flags);
 
+       if (ready)
+               /* Increment fabric iocb count to hold the position */
+               atomic_inc(&phba->fabric_iocb_count);
        spin_unlock_irqrestore(&phba->hbalock, iflags);
        if (ready) {
                iocb->fabric_iocb_cmpl = iocb->iocb_cmpl;
@@ -4725,8 +6674,7 @@ lpfc_issue_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *iocb)
                        "Fabric sched2:   ste:x%x",
                        iocb->vport->port_state, 0, 0);
 
-               atomic_inc(&phba->fabric_iocb_count);
-               ret = lpfc_sli_issue_iocb(phba, pring, iocb, 0);
+               ret = lpfc_sli_issue_iocb(phba, LPFC_ELS_RING, iocb, 0);
 
                if (ret == IOCB_ERROR) {
                        iocb->iocb_cmpl = iocb->fabric_iocb_cmpl;
@@ -4743,13 +6691,22 @@ lpfc_issue_fabric_iocb(struct lpfc_hba *phba, struct lpfc_iocbq *iocb)
        return ret;
 }
 
-
+/**
+ * lpfc_fabric_abort_vport - Abort a vport's iocbs from driver fabric iocb list
+ * @vport: pointer to a virtual N_Port data structure.
+ *
+ * This routine aborts all the IOCBs associated with a @vport from the
+ * driver internal fabric IOCB list. The list contains fabric IOCBs to be
+ * issued to the ELS IOCB ring. This abort function walks the fabric IOCB
+ * list, removes each IOCB associated with the @vport off the list, set the
+ * status feild to IOSTAT_LOCAL_REJECT, and invokes the callback function
+ * associated with the IOCB.
+ **/
 static void lpfc_fabric_abort_vport(struct lpfc_vport *vport)
 {
        LIST_HEAD(completions);
        struct lpfc_hba  *phba = vport->phba;
        struct lpfc_iocbq *tmp_iocb, *piocb;
-       IOCB_t *cmd;
 
        spin_lock_irq(&phba->hbalock);
        list_for_each_entry_safe(piocb, tmp_iocb, &phba->fabric_iocb_list,
@@ -4762,24 +6719,28 @@ static void lpfc_fabric_abort_vport(struct lpfc_vport *vport)
        }
        spin_unlock_irq(&phba->hbalock);
 
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               list_del_init(&piocb->list);
-
-               cmd = &piocb->iocb;
-               cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-               cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-               (piocb->iocb_cmpl) (phba, piocb, piocb);
-       }
+       /* Cancel all the IOCBs from the completions list */
+       lpfc_sli_cancel_iocbs(phba, &completions, IOSTAT_LOCAL_REJECT,
+                             IOERR_SLI_ABORTED);
 }
 
+/**
+ * lpfc_fabric_abort_nport - Abort a ndlp's iocbs from driver fabric iocb list
+ * @ndlp: pointer to a node-list data structure.
+ *
+ * This routine aborts all the IOCBs associated with an @ndlp from the
+ * driver internal fabric IOCB list. The list contains fabric IOCBs to be
+ * issued to the ELS IOCB ring. This abort function walks the fabric IOCB
+ * list, removes each IOCB associated with the @ndlp off the list, set the
+ * status feild to IOSTAT_LOCAL_REJECT, and invokes the callback function
+ * associated with the IOCB.
+ **/
 void lpfc_fabric_abort_nport(struct lpfc_nodelist *ndlp)
 {
        LIST_HEAD(completions);
-       struct lpfc_hba  *phba = ndlp->vport->phba;
+       struct lpfc_hba  *phba = ndlp->phba;
        struct lpfc_iocbq *tmp_iocb, *piocb;
        struct lpfc_sli_ring *pring = &phba->sli.ring[LPFC_ELS_RING];
-       IOCB_t *cmd;
 
        spin_lock_irq(&phba->hbalock);
        list_for_each_entry_safe(piocb, tmp_iocb, &phba->fabric_iocb_list,
@@ -4791,70 +6752,66 @@ void lpfc_fabric_abort_nport(struct lpfc_nodelist *ndlp)
        }
        spin_unlock_irq(&phba->hbalock);
 
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               list_del_init(&piocb->list);
-
-               cmd = &piocb->iocb;
-               cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-               cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-               (piocb->iocb_cmpl) (phba, piocb, piocb);
-       }
+       /* Cancel all the IOCBs from the completions list */
+       lpfc_sli_cancel_iocbs(phba, &completions, IOSTAT_LOCAL_REJECT,
+                             IOERR_SLI_ABORTED);
 }
 
+/**
+ * lpfc_fabric_abort_hba - Abort all iocbs on driver fabric iocb list
+ * @phba: pointer to lpfc hba data structure.
+ *
+ * This routine aborts all the IOCBs currently on the driver internal
+ * fabric IOCB list. The list contains fabric IOCBs to be issued to the ELS
+ * IOCB ring. This function takes the entire IOCB list off the fabric IOCB
+ * list, removes IOCBs off the list, set the status feild to
+ * IOSTAT_LOCAL_REJECT, and invokes the callback function associated with
+ * the IOCB.
+ **/
 void lpfc_fabric_abort_hba(struct lpfc_hba *phba)
 {
        LIST_HEAD(completions);
-       struct lpfc_iocbq *piocb;
-       IOCB_t *cmd;
 
        spin_lock_irq(&phba->hbalock);
        list_splice_init(&phba->fabric_iocb_list, &completions);
        spin_unlock_irq(&phba->hbalock);
 
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               list_del_init(&piocb->list);
-
-               cmd = &piocb->iocb;
-               cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-               cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-               (piocb->iocb_cmpl) (phba, piocb, piocb);
-       }
+       /* Cancel all the IOCBs from the completions list */
+       lpfc_sli_cancel_iocbs(phba, &completions, IOSTAT_LOCAL_REJECT,
+                             IOERR_SLI_ABORTED);
 }
 
-
-#if 0
-void lpfc_fabric_abort_flogi(struct lpfc_hba *phba)
+/**
+ * lpfc_sli4_els_xri_aborted - Slow-path process of els xri abort
+ * @phba: pointer to lpfc hba data structure.
+ * @axri: pointer to the els xri abort wcqe structure.
+ *
+ * This routine is invoked by the worker thread to process a SLI4 slow-path
+ * ELS aborted xri.
+ **/
+void
+lpfc_sli4_els_xri_aborted(struct lpfc_hba *phba,
+                         struct sli4_wcqe_xri_aborted *axri)
 {
-       LIST_HEAD(completions);
-       struct lpfc_iocbq *tmp_iocb, *piocb;
-       IOCB_t *cmd;
-       struct lpfc_nodelist *ndlp;
-
-       spin_lock_irq(&phba->hbalock);
-       list_for_each_entry_safe(piocb, tmp_iocb, &phba->fabric_iocb_list,
-                                list) {
-
-               cmd = &piocb->iocb;
-               ndlp = (struct lpfc_nodelist *) piocb->context1;
-               if (cmd->ulpCommand == CMD_ELS_REQUEST64_CR &&
-                   ndlp != NULL &&
-                   ndlp->nlp_DID == Fabric_DID)
-                       list_move_tail(&piocb->list, &completions);
-       }
-       spin_unlock_irq(&phba->hbalock);
-
-       while (!list_empty(&completions)) {
-               piocb = list_get_first(&completions, struct lpfc_iocbq, list);
-               list_del_init(&piocb->list);
-
-               cmd = &piocb->iocb;
-               cmd->ulpStatus = IOSTAT_LOCAL_REJECT;
-               cmd->un.ulpWord[4] = IOERR_SLI_ABORTED;
-               (piocb->iocb_cmpl) (phba, piocb, piocb);
+       uint16_t xri = bf_get(lpfc_wcqe_xa_xri, axri);
+       struct lpfc_sglq *sglq_entry = NULL, *sglq_next = NULL;
+       unsigned long iflag = 0;
+
+       spin_lock_irqsave(&phba->sli4_hba.abts_sgl_list_lock, iflag);
+       list_for_each_entry_safe(sglq_entry, sglq_next,
+                       &phba->sli4_hba.lpfc_abts_els_sgl_list, list) {
+               if (sglq_entry->sli4_xritag == xri) {
+                       list_del(&sglq_entry->list);
+                       spin_unlock_irqrestore(
+                                       &phba->sli4_hba.abts_sgl_list_lock,
+                                        iflag);
+                       spin_lock_irqsave(&phba->hbalock, iflag);
+
+                       list_add_tail(&sglq_entry->list,
+                               &phba->sli4_hba.lpfc_sgl_list);
+                       spin_unlock_irqrestore(&phba->hbalock, iflag);
+                       return;
+               }
        }
+       spin_unlock_irqrestore(&phba->sli4_hba.abts_sgl_list_lock, iflag);
 }
-#endif  /*  0  */
-
-