From bdf79ec8dc772d492dc75a4cb75525431230fadb Mon Sep 17 00:00:00 2001
From: Michael Brown <mcb30@etherboot.org>
Date: Thu, 4 Jan 2007 03:09:28 +0000
Subject: [PATCH] Use hotplug support to notify persistent reference holders
 when a net_device is unregistered.

---
 src/include/gpxe/netdevice.h | 5 +++++
 src/net/netdevice.c          | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/src/include/gpxe/netdevice.h b/src/include/gpxe/netdevice.h
index b7ec83d9..7551be74 100644
--- a/src/include/gpxe/netdevice.h
+++ b/src/include/gpxe/netdevice.h
@@ -10,6 +10,7 @@
 #include <stdint.h>
 #include <gpxe/list.h>
 #include <gpxe/tables.h>
+#include <gpxe/hotplug.h>
 
 struct pk_buff;
 struct net_device;
@@ -137,6 +138,10 @@ struct ll_protocol {
 struct net_device {
 	/** List of network devices */
 	struct list_head list;
+
+	/** List of persistent reference holders */
+	struct list_head references;
+
 	/** Transmit packet
 	 *
 	 * @v netdev	Network device
diff --git a/src/net/netdevice.c b/src/net/netdevice.c
index 3f8e54bb..3949d26d 100644
--- a/src/net/netdevice.c
+++ b/src/net/netdevice.c
@@ -161,6 +161,7 @@ struct net_device * alloc_netdev ( size_t priv_size ) {
 
 	netdev = calloc ( 1, sizeof ( *netdev ) + priv_size );
 	if ( netdev ) {
+		INIT_LIST_HEAD ( &netdev->references );
 		INIT_LIST_HEAD ( &netdev->rx_queue );
 		netdev->priv = ( ( ( void * ) netdev ) + sizeof ( *netdev ) );
 	}
@@ -201,6 +202,9 @@ void unregister_netdev ( struct net_device *netdev ) {
 		free_pkb ( pkb );
 	}
 
+	/* Kill off any persistent references to this device */
+	forget_references ( &netdev->references );
+
 	/* Remove from device list */
 	list_del ( &netdev->list );
 	DBG ( "%s unregistered\n", netdev_name ( netdev ) );