[NET]: Kill NETIF_F_DYNALLOC, based upon ideas from Adam J. Richter

drivers/net/ppp_generic.c

@@ -2214,6 +2214,11 @@ ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
  * and for initialization.
  */
 
+static void ppp_device_destructor(struct net_device *dev)
+{
+	kfree(dev);
+}
+
 /*
  * Create a new ppp interface unit.  Fails if it can't allocate memory
  * or if there is already a unit with the requested number.
@@ -2262,7 +2267,7 @@ ppp_create_interface(int unit, int *retp)
 	dev->init = ppp_net_init;
 	sprintf(dev->name, "ppp%d", unit);
 	dev->priv = ppp;
-	dev->features |= NETIF_F_DYNALLOC;
+	dev->destructor = ppp_device_destructor;
 
 	rtnl_lock();
 	ret = register_netdevice(dev);

include/linux/netdevice.h

@@ -365,7 +365,6 @@ struct net_device
 #define NETIF_F_IP_CSUM		2	/* Can checksum only TCP/UDP over IPv4. */
 #define NETIF_F_NO_CSUM		4	/* Does not require checksum. F.e. loopack. */
 #define NETIF_F_HW_CSUM		8	/* Can checksum all the packets. */
-#define NETIF_F_DYNALLOC	16	/* Self-dectructable device. */
 #define NETIF_F_HIGHDMA		32	/* Can DMA to high memory. */
 #define NETIF_F_FRAGLIST	64	/* Scatter/gather IO. */
 #define NETIF_F_HW_VLAN_TX	128	/* Transmit VLAN hw acceleration */

net/8021q/vlan.c

@@ -433,7 +433,6 @@ static struct net_device *register_vlan_device(const char *eth_IF_name,
 	/* set up method calls */
 	new_dev->init = vlan_dev_init;
 	new_dev->destructor = vlan_dev_destruct;
-	new_dev->features |= NETIF_F_DYNALLOC ; 
 	    
 	/* new_dev->ifindex = 0;  it will be set when added to
 	 * the global list.

net/8021q/vlan_dev.c

@@ -785,6 +785,7 @@ void vlan_dev_destruct(struct net_device *dev)
 			kfree(dev->priv);
 			dev->priv = NULL;
 		}
+		kfree(dev);
 	}
 }
 

net/core/dev.c

@@ -2639,12 +2639,10 @@ int netdev_finish_unregister(struct net_device *dev)
 	}
 #ifdef NET_REFCNT_DEBUG
 	printk(KERN_DEBUG "netdev_finish_unregister: %s%s.\n", dev->name,
-	       (dev->features & NETIF_F_DYNALLOC)?"":", old style");
+	       (dev->destructor != NULL)?"":", old style");
 #endif
 	if (dev->destructor)
 		dev->destructor(dev);
-	if (dev->features & NETIF_F_DYNALLOC)
-		kfree(dev);
 	return 0;
 }
 
@@ -2724,7 +2722,7 @@ int unregister_netdevice(struct net_device *dev)
 	free_divert_blk(dev);
 #endif
 
-	if (dev->features & NETIF_F_DYNALLOC) {
+	if (dev->destructor != NULL) {
 #ifdef NET_REFCNT_DEBUG
 		if (atomic_read(&dev->refcnt) != 1)
 			printk(KERN_DEBUG "unregister_netdevice: holding %s "

net/core/dst.c

@@ -228,7 +228,7 @@ static int dst_dev_event(struct notifier_block *this, unsigned long event, void
 				   _race_ _condition_.
 				 */
 				if (event!=NETDEV_DOWN &&
-				    !(dev->features & NETIF_F_DYNALLOC) &&
+				    dev->destructor == NULL &&
 				    dst->output == dst_blackhole) {
 					dst->dev = &loopback_dev;
 					dev_put(dev);

net/ipv4/ip_gre.c

@@ -273,7 +273,6 @@ static struct ip_tunnel * ipgre_tunnel_locate(struct ip_tunnel_parm *parms, int
 	nt = (struct ip_tunnel*)dev->priv;
 	nt->dev = dev;
 	dev->init = ipgre_tunnel_init;
-	dev->features |= NETIF_F_DYNALLOC;
 	memcpy(&nt->parms, parms, sizeof(*parms));
 	nt->parms.name[IFNAMSIZ-1] = '\0';
 	strcpy(dev->name, nt->parms.name);
@@ -305,6 +304,7 @@ static struct ip_tunnel * ipgre_tunnel_locate(struct ip_tunnel_parm *parms, int
 static void ipgre_tunnel_destructor(struct net_device *dev)
 {
 	if (dev != &ipgre_fb_tunnel_dev) {
+		kfree(dev);
 		MOD_DEC_USE_COUNT;
 	}
 }

net/ipv4/ipip.c

@@ -242,7 +242,6 @@ struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int create)
 	nt = (struct ip_tunnel*)dev->priv;
 	nt->dev = dev;
 	dev->init = ipip_tunnel_init;
-	dev->features |= NETIF_F_DYNALLOC;
 	memcpy(&nt->parms, parms, sizeof(*parms));
 	nt->parms.name[IFNAMSIZ-1] = '\0';
 	strcpy(dev->name, nt->parms.name);
@@ -274,6 +273,7 @@ struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int create)
 static void ipip_tunnel_destructor(struct net_device *dev)
 {
 	if (dev != &ipip_fb_tunnel_dev) {
+		kfree(dev);
 		MOD_DEC_USE_COUNT;
 	}
 }

net/ipv4/ipmr.c

@@ -182,6 +182,11 @@ static struct net_device_stats *reg_vif_get_stats(struct net_device *dev)
 	return (struct net_device_stats*)dev->priv;
 }
 
+static void vif_dev_destructor(struct net_device *dev)
+{
+	kfree(dev);
+}
+
 static
 struct net_device *ipmr_reg_vif(struct vifctl *v)
 {
@@ -205,7 +210,7 @@ struct net_device *ipmr_reg_vif(struct vifctl *v)
 	dev->flags		= IFF_NOARP;
 	dev->hard_start_xmit	= reg_vif_xmit;
 	dev->get_stats		= reg_vif_get_stats;
-	dev->features		|= NETIF_F_DYNALLOC;
+	dev->destructor		= vif_dev_destructor;
 
 	if (register_netdevice(dev)) {
 		kfree(dev);

net/ipv6/sit.c

@@ -181,7 +181,6 @@ static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int
 	nt = (struct ip_tunnel*)dev->priv;
 	nt->dev = dev;
 	dev->init = ipip6_tunnel_init;
-	dev->features |= NETIF_F_DYNALLOC;
 	memcpy(&nt->parms, parms, sizeof(*parms));
 	nt->parms.name[IFNAMSIZ-1] = '\0';
 	strcpy(dev->name, nt->parms.name);
@@ -213,6 +212,7 @@ static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int
 static void ipip6_tunnel_destructor(struct net_device *dev)
 {
 	if (dev != &ipip6_fb_tunnel_dev) {
+		kfree(dev);
 		MOD_DEC_USE_COUNT;
 	}
 }

net/irda/irda_device.c

@@ -372,6 +372,11 @@ static void irda_task_timer_expired(void *data)
 	irda_task_kick(task);
 }
 
+static void irda_device_destructor(struct net_device *dev)
+{
+	kfree(dev);
+}
+
 /*
  * Function irda_device_setup (dev)
  *
@@ -385,8 +390,7 @@ int irda_device_setup(struct net_device *dev)
         dev->hard_header_len = 0;
         dev->addr_len        = 0;
 
-	dev->features        |= NETIF_F_DYNALLOC;
-	/* dev->destructor      = irda_device_destructor; */
+	dev->destructor      = irda_device_destructor;
 
         dev->type            = ARPHRD_IRDA;
         dev->tx_queue_len    = 8; /* Window size + 1 s-frame */

net/irda/irlan/irlan_eth.c

@@ -62,16 +62,6 @@ int irlan_eth_init(struct net_device *dev)
 	dev->get_stats	        = irlan_eth_get_stats;
 	dev->set_multicast_list = irlan_eth_set_multicast_list;
 
-	/* NETIF_F_DYNALLOC feature was set by irlan_eth_init() and would
-	 * cause the unregister_netdev() to do asynch completion _and_
-	 * kfree self->dev afterwards. Which is really bad because the
-	 * netdevice was not allocated separately but is embedded in
-	 * our control block and therefore gets freed with *self.
-	 * The only reason why this would have been enabled is to hide
-	 * some netdev refcount issues. If unregister_netdev() blocks
-	 * forever, tell us about it... */
-	//dev->features          |= NETIF_F_DYNALLOC;
-
 	ether_setup(dev);
 	
 	/*