ibmvfc: Fix endless PRLI loop in discovery

Fixes a problem seen where sending a PRLI to a target
resulted in it sending a LOGO. This caused the ibmvfc
driver to go back through discovery again, which caused
another PRLI attempt, which caused another LOGO. Fix this
behavior by ignoring LOGO if we haven't even logged into
the target yet.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 497a4cc..166d964 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -2254,10 +2254,13 @@
 				continue;
 			if (crq->node_name && tgt->ids.node_name != crq->node_name)
 				continue;
-			ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_DEL_RPORT);
+			if (tgt->need_login && crq->event == IBMVFC_AE_ELS_LOGO)
+				tgt->logo_rcvd = 1;
+			if (!tgt->need_login || crq->event == IBMVFC_AE_ELS_PLOGI) {
+				ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_DEL_RPORT);
+				ibmvfc_reinit_host(vhost);
+			}
 		}
-
-		ibmvfc_reinit_host(vhost);
 		break;
 	case IBMVFC_AE_LINK_DOWN:
 	case IBMVFC_AE_ADAPTER_FAILED:
@@ -2927,7 +2930,11 @@
 		break;
 	case IBMVFC_MAD_FAILED:
 	default:
-		if (ibmvfc_retry_cmd(rsp->status, rsp->error))
+		if ((rsp->status & IBMVFC_VIOS_FAILURE) && rsp->error == IBMVFC_PLOGI_REQUIRED)
+			level += ibmvfc_retry_tgt_init(tgt, ibmvfc_tgt_send_plogi);
+		else if (tgt->logo_rcvd)
+			level += ibmvfc_retry_tgt_init(tgt, ibmvfc_tgt_send_plogi);
+		else if (ibmvfc_retry_cmd(rsp->status, rsp->error))
 			level += ibmvfc_retry_tgt_init(tgt, ibmvfc_tgt_send_prli);
 		else
 			ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_DEL_RPORT);
@@ -3054,6 +3061,7 @@
 		return;
 
 	kref_get(&tgt->kref);
+	tgt->logo_rcvd = 0;
 	evt = ibmvfc_get_event(vhost);
 	vhost->discovery_threads++;
 	ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_INIT_WAIT);