scsi: lpfc: Fix used-RPI accounting problem.

With 255 vports created a link trasition can casue a crash.

When going through discovery after a link bounce the driver is using
rpis before the cmd FCOE_POST_HDR_TEMPLATES completes. By doing that the
next rpi bumps the rpi range out of the boundary.

The fix it to increment the next_rpi only when the
FCOE_POST_HDR_TEMPLATE succeeds.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/lpfc/lpfc_els.c

@@ -8667,7 +8667,8 @@ lpfc_cmpl_els_fdisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 		lpfc_do_scr_ns_plogi(phba, vport);
 	goto out;
 fdisc_failed:
-	if (vport->fc_vport->vport_state != FC_VPORT_NO_FABRIC_RSCS)
+	if (vport->fc_vport &&
+	    (vport->fc_vport->vport_state != FC_VPORT_NO_FABRIC_RSCS))
 		lpfc_vport_set_state(vport, FC_VPORT_FAILED);
 	/* Cancel discovery timer */
 	lpfc_can_disctmo(vport);

drivers/scsi/lpfc/lpfc_init.c

@@ -6525,7 +6525,6 @@ lpfc_sli4_create_rpi_hdr(struct lpfc_hba *phba)
 	uint16_t rpi_limit, curr_rpi_range;
 	struct lpfc_dmabuf *dmabuf;
 	struct lpfc_rpi_hdr *rpi_hdr;
-	uint32_t rpi_count;
 
 	/*
 	 * If the SLI4 port supports extents, posting the rpi header isn't
@@ -6538,8 +6537,7 @@ lpfc_sli4_create_rpi_hdr(struct lpfc_hba *phba)
 		return NULL;
 
 	/* The limit on the logical index is just the max_rpi count. */
-	rpi_limit = phba->sli4_hba.max_cfg_param.rpi_base +
-	phba->sli4_hba.max_cfg_param.max_rpi - 1;
+	rpi_limit = phba->sli4_hba.max_cfg_param.max_rpi;
 
 	spin_lock_irq(&phba->hbalock);
 	/*
@@ -6550,18 +6548,10 @@ lpfc_sli4_create_rpi_hdr(struct lpfc_hba *phba)
 	curr_rpi_range = phba->sli4_hba.next_rpi;
 	spin_unlock_irq(&phba->hbalock);
 
-	/*
-	 * The port has a limited number of rpis. The increment here
-	 * is LPFC_RPI_HDR_COUNT - 1 to account for the starting value
-	 * and to allow the full max_rpi range per port.
-	 */
-	if ((curr_rpi_range + (LPFC_RPI_HDR_COUNT - 1)) > rpi_limit)
-		rpi_count = rpi_limit - curr_rpi_range;
-	else
-		rpi_count = LPFC_RPI_HDR_COUNT;
-
-	if (!rpi_count)
+	/* Reached full RPI range */
+	if (curr_rpi_range == rpi_limit)
 		return NULL;
+
 	/*
 	 * First allocate the protocol header region for the port.  The
 	 * port expects a 4KB DMA-mapped memory region that is 4K aligned.
@@ -6595,13 +6585,9 @@ lpfc_sli4_create_rpi_hdr(struct lpfc_hba *phba)
 
 	/* The rpi_hdr stores the logical index only. */
 	rpi_hdr->start_rpi = curr_rpi_range;
+	rpi_hdr->next_rpi = phba->sli4_hba.next_rpi + LPFC_RPI_HDR_COUNT;
 	list_add_tail(&rpi_hdr->list, &phba->sli4_hba.lpfc_rpi_hdr_list);
 
-	/*
-	 * The next_rpi stores the next logical module-64 rpi value used
-	 * to post physical rpis in subsequent rpi postings.
-	 */
-	phba->sli4_hba.next_rpi += rpi_count;
 	spin_unlock_irq(&phba->hbalock);
 	return rpi_hdr;
 

drivers/scsi/lpfc/lpfc_sli.c

@@ -17137,6 +17137,14 @@ lpfc_sli4_post_rpi_hdr(struct lpfc_hba *phba, struct lpfc_rpi_hdr *rpi_page)
 				"status x%x add_status x%x, mbx status x%x\n",
 				shdr_status, shdr_add_status, rc);
 		rc = -ENXIO;
+	} else {
+		/*
+		 * The next_rpi stores the next logical module-64 rpi value used
+		 * to post physical rpis in subsequent rpi postings.
+		 */
+		spin_lock_irq(&phba->hbalock);
+		phba->sli4_hba.next_rpi = rpi_page->next_rpi;
+		spin_unlock_irq(&phba->hbalock);
 	}
 	return rc;
 }

drivers/scsi/lpfc/lpfc_sli4.h

@@ -698,6 +698,7 @@ struct lpfc_rpi_hdr {
 	struct lpfc_dmabuf *dmabuf;
 	uint32_t page_count;
 	uint32_t start_rpi;
+	uint16_t next_rpi;
 };
 
 struct lpfc_rsrc_blks {