net/ieee802154/core.c - kernel/common - Git at Google

 /*
  * Copyright (C) 2007, 2008, 2009 Siemens AG
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2
  * as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  */

 #include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/device.h>

 #include <net/cfg802154.h>
 #include <net/rtnetlink.h>

 #include "ieee802154.h"
 #include "nl802154.h"
 #include "sysfs.h"
 #include "core.h"

 /* name for sysfs, %d is appended */
 #define PHY_NAME "phy"

 /* RCU-protected (and RTNL for writers) */
 LIST_HEAD(cfg802154_rdev_list);
 int cfg802154_rdev_list_generation;

 static int wpan_phy_match(struct device *dev, const void *data)
 {
 	return !strcmp(dev_name(dev), (const char *)data);
 }

 struct wpan_phy *wpan_phy_find(const char *str)
 {
 	struct device *dev;

 	if (WARN_ON(!str))
 		return NULL;

 	dev = class_find_device(&wpan_phy_class, NULL, str, wpan_phy_match);
 	if (!dev)
 		return NULL;

 	return container_of(dev, struct wpan_phy, dev);
 }
 EXPORT_SYMBOL(wpan_phy_find);

 struct wpan_phy_iter_data {
 	int (*fn)(struct wpan_phy *phy, void *data);
 	void *data;
 };

 static int wpan_phy_iter(struct device *dev, void *_data)
 {
 	struct wpan_phy_iter_data *wpid = _data;
 	struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);

 	return wpid->fn(phy, wpid->data);
 }

 int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data),
 		      void *data)
 {
 	struct wpan_phy_iter_data wpid = {
 		.fn = fn,
 		.data = data,
 	};

 	return class_for_each_device(&wpan_phy_class, NULL,
 			&wpid, wpan_phy_iter);
 }
 EXPORT_SYMBOL(wpan_phy_for_each);

 struct cfg802154_registered_device *
 cfg802154_rdev_by_wpan_phy_idx(int wpan_phy_idx)
 {
 	struct cfg802154_registered_device *result = NULL, *rdev;

 	ASSERT_RTNL();

 	list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
 		if (rdev->wpan_phy_idx == wpan_phy_idx) {
 			result = rdev;
 			break;
 		}
 	}

 	return result;
 }

 struct wpan_phy *wpan_phy_idx_to_wpan_phy(int wpan_phy_idx)
 {
 	struct cfg802154_registered_device *rdev;

 	ASSERT_RTNL();

 	rdev = cfg802154_rdev_by_wpan_phy_idx(wpan_phy_idx);
 	if (!rdev)
 		return NULL;
 	return &rdev->wpan_phy;
 }

 struct wpan_phy *
 wpan_phy_new(const struct cfg802154_ops *ops, size_t priv_size)
 {
 	static atomic_t wpan_phy_counter = ATOMIC_INIT(0);
 	struct cfg802154_registered_device *rdev;
 	size_t alloc_size;

 	alloc_size = sizeof(*rdev) + priv_size;
 	rdev = kzalloc(alloc_size, GFP_KERNEL);
 	if (!rdev)
 		return NULL;

 	rdev->ops = ops;

 	rdev->wpan_phy_idx = atomic_inc_return(&wpan_phy_counter);

 	if (unlikely(rdev->wpan_phy_idx < 0)) {
 		/* ugh, wrapped! */
 		atomic_dec(&wpan_phy_counter);
 		kfree(rdev);
 		return NULL;
 	}

 	/* atomic_inc_return makes it start at 1, make it start at 0 */
 	rdev->wpan_phy_idx--;

 	INIT_LIST_HEAD(&rdev->wpan_dev_list);
 	device_initialize(&rdev->wpan_phy.dev);
 	dev_set_name(&rdev->wpan_phy.dev, PHY_NAME "%d", rdev->wpan_phy_idx);

 	rdev->wpan_phy.dev.class = &wpan_phy_class;
 	rdev->wpan_phy.dev.platform_data = rdev;

 	wpan_phy_net_set(&rdev->wpan_phy, &init_net);

 	init_waitqueue_head(&rdev->dev_wait);

 	return &rdev->wpan_phy;
 }
 EXPORT_SYMBOL(wpan_phy_new);

 int wpan_phy_register(struct wpan_phy *phy)
 {
 	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);
 	int ret;

 	rtnl_lock();
 	ret = device_add(&phy->dev);
 	if (ret) {
 		rtnl_unlock();
 		return ret;
 	}

 	list_add_rcu(&rdev->list, &cfg802154_rdev_list);
 	cfg802154_rdev_list_generation++;

 	/* TODO phy registered lock */
 	rtnl_unlock();

 	/* TODO nl802154 phy notify */

 	return 0;
 }
 EXPORT_SYMBOL(wpan_phy_register);

 void wpan_phy_unregister(struct wpan_phy *phy)
 {
 	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);

 	wait_event(rdev->dev_wait, ({
 		int __count;
 		rtnl_lock();
 		__count = rdev->opencount;
 		rtnl_unlock();
 		__count == 0; }));

 	rtnl_lock();
 	/* TODO nl802154 phy notify */
 	/* TODO phy registered lock */

 	WARN_ON(!list_empty(&rdev->wpan_dev_list));

 	/* First remove the hardware from everywhere, this makes
 	 * it impossible to find from userspace.
 	 */
 	list_del_rcu(&rdev->list);
 	synchronize_rcu();

 	cfg802154_rdev_list_generation++;

 	device_del(&phy->dev);

 	rtnl_unlock();
 }
 EXPORT_SYMBOL(wpan_phy_unregister);

 void wpan_phy_free(struct wpan_phy *phy)
 {
 	put_device(&phy->dev);
 }
 EXPORT_SYMBOL(wpan_phy_free);

 int cfg802154_switch_netns(struct cfg802154_registered_device *rdev,
 			   struct net *net)
 {
 	struct wpan_dev *wpan_dev;
 	int err = 0;

 	list_for_each_entry(wpan_dev, &rdev->wpan_dev_list, list) {
 		if (!wpan_dev->netdev)
 			continue;
 		wpan_dev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 		err = dev_change_net_namespace(wpan_dev->netdev, net, "wpan%d");
 		if (err)
 			break;
 		wpan_dev->netdev->features |= NETIF_F_NETNS_LOCAL;
 	}

 	if (err) {
 		/* failed -- clean up to old netns */
 		net = wpan_phy_net(&rdev->wpan_phy);

 		list_for_each_entry_continue_reverse(wpan_dev,
 						     &rdev->wpan_dev_list,
 						     list) {
 			if (!wpan_dev->netdev)
 				continue;
 			wpan_dev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 			err = dev_change_net_namespace(wpan_dev->netdev, net,
 						       "wpan%d");
 			WARN_ON(err);
 			wpan_dev->netdev->features |= NETIF_F_NETNS_LOCAL;
 		}

 		return err;
 	}

 	wpan_phy_net_set(&rdev->wpan_phy, net);

 	err = device_rename(&rdev->wpan_phy.dev, dev_name(&rdev->wpan_phy.dev));
 	WARN_ON(err);

 	return 0;
 }

 void cfg802154_dev_free(struct cfg802154_registered_device *rdev)
 {
 	kfree(rdev);
 }

 static void
 cfg802154_update_iface_num(struct cfg802154_registered_device *rdev,
 			   int iftype, int num)
 {
 	ASSERT_RTNL();

 	rdev->num_running_ifaces += num;
 }

 static int cfg802154_netdev_notifier_call(struct notifier_block *nb,
 					  unsigned long state, void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 	struct cfg802154_registered_device *rdev;

 	if (!wpan_dev)
 		return NOTIFY_DONE;

 	rdev = wpan_phy_to_rdev(wpan_dev->wpan_phy);

 	/* TODO WARN_ON unspec type */

 	switch (state) {
 		/* TODO NETDEV_DEVTYPE */
 	case NETDEV_REGISTER:
 		dev->features |= NETIF_F_NETNS_LOCAL;
 		wpan_dev->identifier = ++rdev->wpan_dev_id;
 		list_add_rcu(&wpan_dev->list, &rdev->wpan_dev_list);
 		rdev->devlist_generation++;

 		wpan_dev->netdev = dev;
 		break;
 	case NETDEV_DOWN:
 		cfg802154_update_iface_num(rdev, wpan_dev->iftype, -1);

 		rdev->opencount--;
 		wake_up(&rdev->dev_wait);
 		break;
 	case NETDEV_UP:
 		cfg802154_update_iface_num(rdev, wpan_dev->iftype, 1);

 		rdev->opencount++;
 		break;
 	case NETDEV_UNREGISTER:
 		/* It is possible to get NETDEV_UNREGISTER
 		 * multiple times. To detect that, check
 		 * that the interface is still on the list
 		 * of registered interfaces, and only then
 		 * remove and clean it up.
 		 */
 		if (!list_empty(&wpan_dev->list)) {
 			list_del_rcu(&wpan_dev->list);
 			rdev->devlist_generation++;
 		}
 		/* synchronize (so that we won't find this netdev
 		 * from other code any more) and then clear the list
 		 * head so that the above code can safely check for
 		 * !list_empty() to avoid double-cleanup.
 		 */
 		synchronize_rcu();
 		INIT_LIST_HEAD(&wpan_dev->list);
 		break;
 	default:
 		return NOTIFY_DONE;
 	}

 	return NOTIFY_OK;
 }

 static struct notifier_block cfg802154_netdev_notifier = {
 	.notifier_call = cfg802154_netdev_notifier_call,
 };

 static void __net_exit cfg802154_pernet_exit(struct net *net)
 {
 	struct cfg802154_registered_device *rdev;

 	rtnl_lock();
 	list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
 		if (net_eq(wpan_phy_net(&rdev->wpan_phy), net))
 			WARN_ON(cfg802154_switch_netns(rdev, &init_net));
 	}
 	rtnl_unlock();
 }

 static struct pernet_operations cfg802154_pernet_ops = {
 	.exit = cfg802154_pernet_exit,
 };

 static int __init wpan_phy_class_init(void)
 {
 	int rc;

 	rc = register_pernet_device(&cfg802154_pernet_ops);
 	if (rc)
 		goto err;

 	rc = wpan_phy_sysfs_init();
 	if (rc)
 		goto err_sysfs;

 	rc = register_netdevice_notifier(&cfg802154_netdev_notifier);
 	if (rc)
 		goto err_nl;

 	rc = ieee802154_nl_init();
 	if (rc)
 		goto err_notifier;

 	rc = nl802154_init();
 	if (rc)
 		goto err_ieee802154_nl;

 	return 0;

 err_ieee802154_nl:
 	ieee802154_nl_exit();

 err_notifier:
 	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
 err_nl:
 	wpan_phy_sysfs_exit();
 err_sysfs:
 	unregister_pernet_device(&cfg802154_pernet_ops);
 err:
 	return rc;
 }
 subsys_initcall(wpan_phy_class_init);

 static void __exit wpan_phy_class_exit(void)
 {
 	nl802154_exit();
 	ieee802154_nl_exit();
 	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
 	wpan_phy_sysfs_exit();
 	unregister_pernet_device(&cfg802154_pernet_ops);
 }
 module_exit(wpan_phy_class_exit);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("IEEE 802.15.4 configuration interface");
 MODULE_AUTHOR("Dmitry Eremin-Solenikov");
	/*
	* Copyright (C) 2007, 2008, 2009 Siemens AG
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2
	* as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	*/

	#include <linux/slab.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/device.h>

	#include <net/cfg802154.h>
	#include <net/rtnetlink.h>

	#include "ieee802154.h"
	#include "nl802154.h"
	#include "sysfs.h"
	#include "core.h"

	/* name for sysfs, %d is appended */
	#define PHY_NAME "phy"

	/* RCU-protected (and RTNL for writers) */
	LIST_HEAD(cfg802154_rdev_list);
	int cfg802154_rdev_list_generation;

	static int wpan_phy_match(struct device dev, const void data)
	{
	return !strcmp(dev_name(dev), (const char *)data);
	}

	struct wpan_phy wpan_phy_find(const char str)
	{
	struct device *dev;

	if (WARN_ON(!str))
	return NULL;

	dev = class_find_device(&wpan_phy_class, NULL, str, wpan_phy_match);
	if (!dev)
	return NULL;

	return container_of(dev, struct wpan_phy, dev);
	}
	EXPORT_SYMBOL(wpan_phy_find);

	struct wpan_phy_iter_data {
	int (fn)(struct wpan_phy phy, void *data);
	void *data;
	};

	static int wpan_phy_iter(struct device dev, void _data)
	{
	struct wpan_phy_iter_data *wpid = _data;
	struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);

	return wpid->fn(phy, wpid->data);
	}

	int wpan_phy_for_each(int (fn)(struct wpan_phy phy, void *data),
	void *data)
	{
	struct wpan_phy_iter_data wpid = {
	.fn = fn,
	.data = data,
	};

	return class_for_each_device(&wpan_phy_class, NULL,
	&wpid, wpan_phy_iter);
	}
	EXPORT_SYMBOL(wpan_phy_for_each);

	struct cfg802154_registered_device *
	cfg802154_rdev_by_wpan_phy_idx(int wpan_phy_idx)
	{
	struct cfg802154_registered_device result = NULL, rdev;

	ASSERT_RTNL();

	list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
	if (rdev->wpan_phy_idx == wpan_phy_idx) {
	result = rdev;
	break;
	}
	}

	return result;
	}

	struct wpan_phy *wpan_phy_idx_to_wpan_phy(int wpan_phy_idx)
	{
	struct cfg802154_registered_device *rdev;

	ASSERT_RTNL();

	rdev = cfg802154_rdev_by_wpan_phy_idx(wpan_phy_idx);
	if (!rdev)
	return NULL;
	return &rdev->wpan_phy;
	}

	struct wpan_phy *
	wpan_phy_new(const struct cfg802154_ops *ops, size_t priv_size)
	{
	static atomic_t wpan_phy_counter = ATOMIC_INIT(0);
	struct cfg802154_registered_device *rdev;
	size_t alloc_size;

	alloc_size = sizeof(*rdev) + priv_size;
	rdev = kzalloc(alloc_size, GFP_KERNEL);
	if (!rdev)
	return NULL;

	rdev->ops = ops;

	rdev->wpan_phy_idx = atomic_inc_return(&wpan_phy_counter);

	if (unlikely(rdev->wpan_phy_idx < 0)) {
	/* ugh, wrapped! */
	atomic_dec(&wpan_phy_counter);
	kfree(rdev);
	return NULL;
	}

	/* atomic_inc_return makes it start at 1, make it start at 0 */
	rdev->wpan_phy_idx--;

	INIT_LIST_HEAD(&rdev->wpan_dev_list);
	device_initialize(&rdev->wpan_phy.dev);
	dev_set_name(&rdev->wpan_phy.dev, PHY_NAME "%d", rdev->wpan_phy_idx);

	rdev->wpan_phy.dev.class = &wpan_phy_class;
	rdev->wpan_phy.dev.platform_data = rdev;

	wpan_phy_net_set(&rdev->wpan_phy, &init_net);

	init_waitqueue_head(&rdev->dev_wait);

	return &rdev->wpan_phy;
	}
	EXPORT_SYMBOL(wpan_phy_new);

	int wpan_phy_register(struct wpan_phy *phy)
	{
	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);
	int ret;

	rtnl_lock();
	ret = device_add(&phy->dev);
	if (ret) {
	rtnl_unlock();
	return ret;
	}

	list_add_rcu(&rdev->list, &cfg802154_rdev_list);
	cfg802154_rdev_list_generation++;

	/* TODO phy registered lock */
	rtnl_unlock();

	/* TODO nl802154 phy notify */

	return 0;
	}
	EXPORT_SYMBOL(wpan_phy_register);

	void wpan_phy_unregister(struct wpan_phy *phy)
	{
	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);

	wait_event(rdev->dev_wait, ({
	int __count;
	rtnl_lock();
	__count = rdev->opencount;
	rtnl_unlock();
	__count == 0; }));

	rtnl_lock();
	/* TODO nl802154 phy notify */
	/* TODO phy registered lock */

	WARN_ON(!list_empty(&rdev->wpan_dev_list));

	/* First remove the hardware from everywhere, this makes
	* it impossible to find from userspace.
	*/
	list_del_rcu(&rdev->list);
	synchronize_rcu();

	cfg802154_rdev_list_generation++;

	device_del(&phy->dev);

	rtnl_unlock();
	}
	EXPORT_SYMBOL(wpan_phy_unregister);

	void wpan_phy_free(struct wpan_phy *phy)
	{
	put_device(&phy->dev);
	}
	EXPORT_SYMBOL(wpan_phy_free);

	int cfg802154_switch_netns(struct cfg802154_registered_device *rdev,
	struct net *net)
	{
	struct wpan_dev *wpan_dev;
	int err = 0;

	list_for_each_entry(wpan_dev, &rdev->wpan_dev_list, list) {
	if (!wpan_dev->netdev)
	continue;
	wpan_dev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
	err = dev_change_net_namespace(wpan_dev->netdev, net, "wpan%d");
	if (err)
	break;
	wpan_dev->netdev->features \|= NETIF_F_NETNS_LOCAL;
	}

	if (err) {
	/* failed -- clean up to old netns */
	net = wpan_phy_net(&rdev->wpan_phy);

	list_for_each_entry_continue_reverse(wpan_dev,
	&rdev->wpan_dev_list,
	list) {
	if (!wpan_dev->netdev)
	continue;
	wpan_dev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
	err = dev_change_net_namespace(wpan_dev->netdev, net,
	"wpan%d");
	WARN_ON(err);
	wpan_dev->netdev->features \|= NETIF_F_NETNS_LOCAL;
	}

	return err;
	}

	wpan_phy_net_set(&rdev->wpan_phy, net);

	err = device_rename(&rdev->wpan_phy.dev, dev_name(&rdev->wpan_phy.dev));
	WARN_ON(err);

	return 0;
	}

	void cfg802154_dev_free(struct cfg802154_registered_device *rdev)
	{
	kfree(rdev);
	}

	static void
	cfg802154_update_iface_num(struct cfg802154_registered_device *rdev,
	int iftype, int num)
	{
	ASSERT_RTNL();

	rdev->num_running_ifaces += num;
	}

	static int cfg802154_netdev_notifier_call(struct notifier_block *nb,
	unsigned long state, void *ptr)
	{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
	struct cfg802154_registered_device *rdev;

	if (!wpan_dev)
	return NOTIFY_DONE;

	rdev = wpan_phy_to_rdev(wpan_dev->wpan_phy);

	/* TODO WARN_ON unspec type */

	switch (state) {
	/* TODO NETDEV_DEVTYPE */
	case NETDEV_REGISTER:
	dev->features \|= NETIF_F_NETNS_LOCAL;
	wpan_dev->identifier = ++rdev->wpan_dev_id;
	list_add_rcu(&wpan_dev->list, &rdev->wpan_dev_list);
	rdev->devlist_generation++;

	wpan_dev->netdev = dev;
	break;
	case NETDEV_DOWN:
	cfg802154_update_iface_num(rdev, wpan_dev->iftype, -1);

	rdev->opencount--;
	wake_up(&rdev->dev_wait);
	break;
	case NETDEV_UP:
	cfg802154_update_iface_num(rdev, wpan_dev->iftype, 1);

	rdev->opencount++;
	break;
	case NETDEV_UNREGISTER:
	/* It is possible to get NETDEV_UNREGISTER
	* multiple times. To detect that, check
	* that the interface is still on the list
	* of registered interfaces, and only then
	* remove and clean it up.
	*/
	if (!list_empty(&wpan_dev->list)) {
	list_del_rcu(&wpan_dev->list);
	rdev->devlist_generation++;
	}
	/* synchronize (so that we won't find this netdev
	* from other code any more) and then clear the list
	* head so that the above code can safely check for
	* !list_empty() to avoid double-cleanup.
	*/
	synchronize_rcu();
	INIT_LIST_HEAD(&wpan_dev->list);
	break;
	default:
	return NOTIFY_DONE;
	}

	return NOTIFY_OK;
	}

	static struct notifier_block cfg802154_netdev_notifier = {
	.notifier_call = cfg802154_netdev_notifier_call,
	};

	static void __net_exit cfg802154_pernet_exit(struct net *net)
	{
	struct cfg802154_registered_device *rdev;

	rtnl_lock();
	list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
	if (net_eq(wpan_phy_net(&rdev->wpan_phy), net))
	WARN_ON(cfg802154_switch_netns(rdev, &init_net));
	}
	rtnl_unlock();
	}

	static struct pernet_operations cfg802154_pernet_ops = {
	.exit = cfg802154_pernet_exit,
	};

	static int __init wpan_phy_class_init(void)
	{
	int rc;

	rc = register_pernet_device(&cfg802154_pernet_ops);
	if (rc)
	goto err;

	rc = wpan_phy_sysfs_init();
	if (rc)
	goto err_sysfs;

	rc = register_netdevice_notifier(&cfg802154_netdev_notifier);
	if (rc)
	goto err_nl;

	rc = ieee802154_nl_init();
	if (rc)
	goto err_notifier;

	rc = nl802154_init();
	if (rc)
	goto err_ieee802154_nl;

	return 0;

	err_ieee802154_nl:
	ieee802154_nl_exit();

	err_notifier:
	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
	err_nl:
	wpan_phy_sysfs_exit();
	err_sysfs:
	unregister_pernet_device(&cfg802154_pernet_ops);
	err:
	return rc;
	}
	subsys_initcall(wpan_phy_class_init);

	static void __exit wpan_phy_class_exit(void)
	{
	nl802154_exit();
	ieee802154_nl_exit();
	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
	wpan_phy_sysfs_exit();
	unregister_pernet_device(&cfg802154_pernet_ops);
	}
	module_exit(wpan_phy_class_exit);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("IEEE 802.15.4 configuration interface");
	MODULE_AUTHOR("Dmitry Eremin-Solenikov");