Commit 2d85cba2 authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[RTNETLINK]: rtnl_link API simplification 



All drivers need to unregister their devices in the module unload function.
While doing so they must hold the rtnl and atomically unregister the
rtnl_link ops as well. This makes the rtnl_link_unregister function that
takes the rtnl itself completely useless.

Provide default newlink/dellink functions, make __rtnl_link_unregister and
rtnl_link_unregister unregister all devices with matching rtnl_link_ops and
change the existing users to take advantage of that.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8c979c26

drivers/net/dummy.c

+3 −54
Original line number Diff line number Diff line
@@ -37,11 +37,6 @@ 
#include <linux/rtnetlink.h>

#include <net/rtnetlink.h>



struct dummy_priv {

	struct net_device *dev;

	struct list_head list;

};



static int numdummies = 1;



static int dummy_xmit(struct sk_buff *skb, struct net_device *dev);
@@ -89,37 +84,9 @@ static int dummy_xmit(struct sk_buff *skb, struct net_device *dev) 
	return 0;

}



static LIST_HEAD(dummies);



static int dummy_newlink(struct net_device *dev,

			 struct nlattr *tb[], struct nlattr *data[])

{

	struct dummy_priv *priv = netdev_priv(dev);

	int err;



	err = register_netdevice(dev);

	if (err < 0)

		return err;



	priv->dev = dev;

	list_add_tail(&priv->list, &dummies);

	return 0;

}



static void dummy_dellink(struct net_device *dev)

{

	struct dummy_priv *priv = netdev_priv(dev);



	list_del(&priv->list);

	unregister_netdevice(dev);

}



static struct rtnl_link_ops dummy_link_ops __read_mostly = {

	.kind		= "dummy",

	.priv_size	= sizeof(struct dummy_priv),

	.setup		= dummy_setup,

	.newlink	= dummy_newlink,

	.dellink	= dummy_dellink,

};



/* Number of dummy devices to be set up by this module. */
@@ -129,12 +96,9 @@ MODULE_PARM_DESC(numdummies, "Number of dummy pseudo devices"); 
static int __init dummy_init_one(void)

{

	struct net_device *dev_dummy;

	struct dummy_priv *priv;

	int err;



	dev_dummy = alloc_netdev(sizeof(struct dummy_priv), "dummy%d",

				 dummy_setup);



	dev_dummy = alloc_netdev(0, "dummy%d", dummy_setup);

	if (!dev_dummy)

		return -ENOMEM;
@@ -146,10 +110,6 @@ static int __init dummy_init_one(void) 
	err = register_netdevice(dev_dummy);

	if (err < 0)

		goto err;



	priv = netdev_priv(dev_dummy);

	priv->dev = dev_dummy;

	list_add_tail(&priv->list, &dummies);

	return 0;



err:
@@ -159,7 +119,6 @@ err: 


static int __init dummy_init_module(void)

{

	struct dummy_priv *priv, *next;

	int i, err = 0;



	rtnl_lock();
@@ -167,11 +126,8 @@ static int __init dummy_init_module(void) 


	for (i = 0; i < numdummies && !err; i++)

		err = dummy_init_one();

	if (err < 0) {

		list_for_each_entry_safe(priv, next, &dummies, list)

			dummy_dellink(priv->dev);

	if (err < 0)

		__rtnl_link_unregister(&dummy_link_ops);

	}

	rtnl_unlock();



	return err;
@@ -179,14 +135,7 @@ static int __init dummy_init_module(void) 


static void __exit dummy_cleanup_module(void)

{

	struct dummy_priv *priv, *next;



	rtnl_lock();

	list_for_each_entry_safe(priv, next, &dummies, list)

		dummy_dellink(priv->dev);



	__rtnl_link_unregister(&dummy_link_ops);

	rtnl_unlock();

	rtnl_link_unregister(&dummy_link_ops);

}



module_init(dummy_init_module);

drivers/net/ifb.c

+6 −52
Original line number Diff line number Diff line
@@ -33,15 +33,12 @@ 
#include <linux/etherdevice.h>

#include <linux/init.h>

#include <linux/moduleparam.h>

#include <linux/list.h>

#include <net/pkt_sched.h>



#define TX_TIMEOUT  (2*HZ)



#define TX_Q_LIMIT    32

struct ifb_private {

	struct list_head	list;

	struct net_device	*dev;

	struct net_device_stats stats;

	struct tasklet_struct   ifb_tasklet;

	int     tasklet_pending;
@@ -201,12 +198,6 @@ static struct net_device_stats *ifb_get_stats(struct net_device *dev) 
	return stats;

}



static LIST_HEAD(ifbs);



/* Number of ifb devices to be set up by this module. */

module_param(numifbs, int, 0);

MODULE_PARM_DESC(numifbs, "Number of ifb devices");



static int ifb_close(struct net_device *dev)

{

	struct ifb_private *dp = netdev_priv(dev);
@@ -230,41 +221,19 @@ static int ifb_open(struct net_device *dev) 
	return 0;

}



static int ifb_newlink(struct net_device *dev,

		       struct nlattr *tb[], struct nlattr *data[])

{

	struct ifb_private *priv = netdev_priv(dev);

	int err;



	err = register_netdevice(dev);

	if (err < 0)

		return err;



	priv->dev = dev;

	list_add_tail(&priv->list, &ifbs);

	return 0;

}



static void ifb_dellink(struct net_device *dev)

{

	struct ifb_private *priv = netdev_priv(dev);



	list_del(&priv->list);

	unregister_netdevice(dev);

}



static struct rtnl_link_ops ifb_link_ops __read_mostly = {

	.kind		= "ifb",

	.priv_size	= sizeof(struct ifb_private),

	.setup		= ifb_setup,

	.newlink	= ifb_newlink,

	.dellink	= ifb_dellink,

};



/* Number of ifb devices to be set up by this module. */

module_param(numifbs, int, 0);

MODULE_PARM_DESC(numifbs, "Number of ifb devices");



static int __init ifb_init_one(int index)

{

	struct net_device *dev_ifb;

	struct ifb_private *priv;

	int err;



	dev_ifb = alloc_netdev(sizeof(struct ifb_private),
@@ -281,10 +250,6 @@ static int __init ifb_init_one(int index) 
	err = register_netdevice(dev_ifb);

	if (err < 0)

		goto err;



	priv = netdev_priv(dev_ifb);

	priv->dev = dev_ifb;

	list_add_tail(&priv->list, &ifbs);

	return 0;



err:
@@ -294,7 +259,6 @@ err: 


static int __init ifb_init_module(void)

{

	struct ifb_private *priv, *next;

	int i, err;



	rtnl_lock();
@@ -302,11 +266,8 @@ static int __init ifb_init_module(void) 


	for (i = 0; i < numifbs && !err; i++)

		err = ifb_init_one(i);

	if (err) {

		list_for_each_entry_safe(priv, next, &ifbs, list)

			ifb_dellink(priv->dev);

	if (err)

		__rtnl_link_unregister(&ifb_link_ops);

	}

	rtnl_unlock();



	return err;
@@ -314,14 +275,7 @@ static int __init ifb_init_module(void) 


static void __exit ifb_cleanup_module(void)

{

	struct ifb_private *priv, *next;



	rtnl_lock();

	list_for_each_entry_safe(priv, next, &ifbs, list)

		ifb_dellink(priv->dev);



	__rtnl_link_unregister(&ifb_link_ops);

	rtnl_unlock();

	rtnl_link_unregister(&ifb_link_ops);

}



module_init(ifb_init_module);

net/8021q/vlan.c

+0 −21
Original line number Diff line number Diff line
@@ -115,26 +115,6 @@ err1: 
	return err;

}



/* Cleanup all vlan devices

 * Note: devices that have been registered that but not

 * brought up will exist but have no module ref count.

 */

static void __exit vlan_cleanup_devices(void)

{

	struct net_device *dev, *nxt;



	rtnl_lock();

	for_each_netdev_safe(dev, nxt) {

		if (dev->priv_flags & IFF_802_1Q_VLAN) {

			unregister_vlan_dev(VLAN_DEV_INFO(dev)->real_dev,

					    VLAN_DEV_INFO(dev)->vlan_id);



			unregister_netdevice(dev);

		}

	}

	rtnl_unlock();

}



/*

 *     Module 'remove' entry point.

 *     o delete /proc/net/router directory and static entries.
@@ -150,7 +130,6 @@ static void __exit vlan_cleanup_module(void) 
	unregister_netdevice_notifier(&vlan_notifier_block);



	dev_remove_pack(&vlan_packet_type);

	vlan_cleanup_devices();



	/* This table must be empty if there are no module

	 * references left.

net/core/rtnetlink.c

+14 −4
Original line number Diff line number Diff line
@@ -270,6 +270,9 @@ static LIST_HEAD(link_ops); 
 */

int __rtnl_link_register(struct rtnl_link_ops *ops)

{

	if (!ops->dellink)

		ops->dellink = unregister_netdevice;



	list_add_tail(&ops->list, &link_ops);

	return 0;

}
@@ -298,12 +301,16 @@ EXPORT_SYMBOL_GPL(rtnl_link_register); 
 * __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.

 * @ops: struct rtnl_link_ops * to unregister

 *

 * The caller must hold the rtnl_mutex. This function should be used

 * by drivers that unregister devices during module unloading. It must

 * be called after unregistering the devices.

 * The caller must hold the rtnl_mutex.

 */

void __rtnl_link_unregister(struct rtnl_link_ops *ops)

{

	struct net_device *dev, *n;



	for_each_netdev_safe(dev, n) {

		if (dev->rtnl_link_ops == ops)

			ops->dellink(dev);

	}

	list_del(&ops->list);

}
@@ -1067,7 +1074,10 @@ replay: 
		if (tb[IFLA_LINKMODE])

			dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);



		if (ops->newlink)

			err = ops->newlink(dev, tb, data);

		else

			err = register_netdevice(dev);

err_free:

		if (err < 0)

			free_netdev(dev);

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