[IA64-SGI] ensure XPC disengage request is processed

This patch fixes a problem in XPC disengage processing whereby it was not
seeing the request to disengage from a remote partition, so the disengage
wasn't happening. The disengagement is suppose to transpire during the time
a XPC channel is disconnecting, and should be completed before the channel
is declared to be disconnected.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/kernel/xpc.h

@@ -707,7 +707,7 @@ extern void xpc_connected_callout(struct xpc_channel *);
 extern void xpc_deliver_msg(struct xpc_channel *);
 extern void xpc_disconnect_channel(const int, struct xpc_channel *,
 					enum xpc_retval, unsigned long *);
-extern void xpc_disconnecting_callout(struct xpc_channel *);
+extern void xpc_disconnect_callout(struct xpc_channel *, enum xpc_retval);
 extern void xpc_partition_going_down(struct xpc_partition *, enum xpc_retval);
 extern void xpc_teardown_infrastructure(struct xpc_partition *);
 

arch/ia64/sn/kernel/xpc_channel.c

@@ -779,6 +779,12 @@ xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
 
 	/* both sides are disconnected now */
 
+	if (ch->flags & XPC_C_CONNECTCALLOUT) {
+		spin_unlock_irqrestore(&ch->lock, *irq_flags);
+		xpc_disconnect_callout(ch, xpcDisconnected);
+		spin_lock_irqsave(&ch->lock, *irq_flags);
+	}
+
 	/* it's now safe to free the channel's message queues */
 	xpc_free_msgqueues(ch);
 
@@ -1645,7 +1651,7 @@ xpc_disconnect_channel(const int line, struct xpc_channel *ch,
 
 
 void
-xpc_disconnecting_callout(struct xpc_channel *ch)
+xpc_disconnect_callout(struct xpc_channel *ch, enum xpc_retval reason)
 {
 	/*
 	 * Let the channel's registerer know that the channel is being
@@ -1654,15 +1660,13 @@ xpc_disconnecting_callout(struct xpc_channel *ch)
 	 */
 
 	if (ch->func != NULL) {
-		dev_dbg(xpc_chan, "ch->func() called, reason=xpcDisconnecting,"
-			" partid=%d, channel=%d\n", ch->partid, ch->number);
+		dev_dbg(xpc_chan, "ch->func() called, reason=%d, partid=%d, "
+			"channel=%d\n", reason, ch->partid, ch->number);
 
-		ch->func(xpcDisconnecting, ch->partid, ch->number, NULL,
-								ch->key);
+		ch->func(reason, ch->partid, ch->number, NULL, ch->key);
 
-		dev_dbg(xpc_chan, "ch->func() returned, reason="
-			"xpcDisconnecting, partid=%d, channel=%d\n",
-			ch->partid, ch->number);
+		dev_dbg(xpc_chan, "ch->func() returned, reason=%d, partid=%d, "
+			"channel=%d\n", reason, ch->partid, ch->number);
 	}
 }
 

arch/ia64/sn/kernel/xpc_main.c

@@ -773,7 +773,7 @@ xpc_daemonize_kthread(void *args)
 			ch->flags |= XPC_C_DISCONNECTCALLOUT;
 			spin_unlock_irqrestore(&ch->lock, irq_flags);
 
-			xpc_disconnecting_callout(ch);
+			xpc_disconnect_callout(ch, xpcDisconnecting);
 		} else {
 			spin_unlock_irqrestore(&ch->lock, irq_flags);
 		}

arch/ia64/sn/kernel/xpc_partition.c

@@ -771,7 +771,8 @@ xpc_identify_act_IRQ_req(int nasid)
 		}
 	}
 
-	if (!xpc_partition_disengaged(part)) {
+	if (part->disengage_request_timeout > 0 &&
+					!xpc_partition_disengaged(part)) {
 		/* still waiting on other side to disengage from us */
 		return;
 	}

include/asm-ia64/sn/xp.h

@@ -227,7 +227,9 @@ enum xpc_retval {
 
 	xpcOpenCloseError,	/* 50: channel open/close protocol error */
 
-	xpcUnknownReason	/* 51: unknown reason -- must be last in list */
+	xpcDisconnected,	/* 51: channel disconnected (closed) */
+
+	xpcUnknownReason	/* 52: unknown reason -- must be last in list */
 };