[deliverable/linux.git] / net / phonet / pn_dev.c

/*
 * File: pn_dev.c
 *
 * Phonet network device
 *
 * Copyright (C) 2008 Nokia Corporation.
 *
 * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
 * Original author: Sakari Ailus <sakari.ailus@nokia.com>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/kernel.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/phonet.h>
#include <net/sock.h>
#include <net/phonet/pn_dev.h>

/* when accessing, remember to lock with spin_lock(&pndevs.lock); */
struct phonet_device_list pndevs = {
	.list = LIST_HEAD_INIT(pndevs.list),
	.lock = __SPIN_LOCK_UNLOCKED(pndevs.lock),
};

/* Allocate new Phonet device. */
static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
{
	struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
	if (pnd == NULL)
		return NULL;
	pnd->netdev = dev;
	bitmap_zero(pnd->addrs, 64);

	list_add(&pnd->list, &pndevs.list);
	return pnd;
}

static struct phonet_device *__phonet_get(struct net_device *dev)
{
	struct phonet_device *pnd;

	list_for_each_entry(pnd, &pndevs.list, list) {
		if (pnd->netdev == dev)
			return pnd;
	}
	return NULL;
}

static void __phonet_device_free(struct phonet_device *pnd)
{
	list_del(&pnd->list);
	kfree(pnd);
}

struct net_device *phonet_device_get(struct net *net)
{
	struct phonet_device *pnd;
	struct net_device *dev;

	spin_lock_bh(&pndevs.lock);
	list_for_each_entry(pnd, &pndevs.list, list) {
		dev = pnd->netdev;
		BUG_ON(!dev);

		if (dev_net(dev) == net &&
			(dev->reg_state == NETREG_REGISTERED) &&
			((pnd->netdev->flags & IFF_UP)) == IFF_UP)
			break;
		dev = NULL;
	}
	if (dev)
		dev_hold(dev);
	spin_unlock_bh(&pndevs.lock);
	return dev;
}

int phonet_address_add(struct net_device *dev, u8 addr)
{
	struct phonet_device *pnd;
	int err = 0;

	spin_lock_bh(&pndevs.lock);
	/* Find or create Phonet-specific device data */
	pnd = __phonet_get(dev);
	if (pnd == NULL)
		pnd = __phonet_device_alloc(dev);
	if (unlikely(pnd == NULL))
		err = -ENOMEM;
	else if (test_and_set_bit(addr >> 2, pnd->addrs))
		err = -EEXIST;
	spin_unlock_bh(&pndevs.lock);
	return err;
}

int phonet_address_del(struct net_device *dev, u8 addr)
{
	struct phonet_device *pnd;
	int err = 0;

	spin_lock_bh(&pndevs.lock);
	pnd = __phonet_get(dev);
	if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs))
		err = -EADDRNOTAVAIL;
	else if (bitmap_empty(pnd->addrs, 64))
		__phonet_device_free(pnd);
	spin_unlock_bh(&pndevs.lock);
	return err;
}

/* Gets a source address toward a destination, through a interface. */
u8 phonet_address_get(struct net_device *dev, u8 addr)
{
	struct phonet_device *pnd;

	spin_lock_bh(&pndevs.lock);
	pnd = __phonet_get(dev);
	if (pnd) {
		BUG_ON(bitmap_empty(pnd->addrs, 64));

		/* Use same source address as destination, if possible */
		if (!test_bit(addr >> 2, pnd->addrs))
			addr = find_first_bit(pnd->addrs, 64) << 2;
	} else
		addr = PN_NO_ADDR;
	spin_unlock_bh(&pndevs.lock);
	return addr;
}

int phonet_address_lookup(u8 addr)
{
	struct phonet_device *pnd;

	spin_lock_bh(&pndevs.lock);
	list_for_each_entry(pnd, &pndevs.list, list) {
		/* Don't allow unregistering devices! */
		if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
				((pnd->netdev->flags & IFF_UP)) != IFF_UP)
			continue;

		if (test_bit(addr >> 2, pnd->addrs)) {
			spin_unlock_bh(&pndevs.lock);
			return 0;
		}
	}
	spin_unlock_bh(&pndevs.lock);
	return -EADDRNOTAVAIL;
}

/* notify Phonet of device events */
static int phonet_device_notify(struct notifier_block *me, unsigned long what,
				void *arg)
{
	struct net_device *dev = arg;

	if (what == NETDEV_UNREGISTER) {
		struct phonet_device *pnd;

		/* Destroy phonet-specific device data */
		spin_lock_bh(&pndevs.lock);
		pnd = __phonet_get(dev);
		if (pnd)
			__phonet_device_free(pnd);
		spin_unlock_bh(&pndevs.lock);
	}
	return 0;

}

static struct notifier_block phonet_device_notifier = {
	.notifier_call = phonet_device_notify,
	.priority = 0,
};

/* Initialize Phonet devices list */
void phonet_device_init(void)
{
	register_netdevice_notifier(&phonet_device_notifier);
}

void phonet_device_exit(void)
{
	struct phonet_device *pnd, *n;

	rtnl_unregister_all(PF_PHONET);
	rtnl_lock();
	spin_lock_bh(&pndevs.lock);

	list_for_each_entry_safe(pnd, n, &pndevs.list, list)
		__phonet_device_free(pnd);

	spin_unlock_bh(&pndevs.lock);
	rtnl_unlock();
	unregister_netdevice_notifier(&phonet_device_notifier);
}
Commit	Line	Data
f8ff6028 RDC	1	/*
	2	* File: pn_dev.c
	3	*
	4	* Phonet network device
	5	*
	6	* Copyright (C) 2008 Nokia Corporation.
	7	*
	8	* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
	9	* Original author: Sakari Ailus <sakari.ailus@nokia.com>
	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* version 2 as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope that it will be useful, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	23	* 02110-1301 USA
	24	*/
	25
	26	#include <linux/kernel.h>
	27	#include <linux/net.h>
	28	#include <linux/netdevice.h>
	29	#include <linux/phonet.h>
	30	#include <net/sock.h>
	31	#include <net/phonet/pn_dev.h>
	32
	33	/* when accessing, remember to lock with spin_lock(&pndevs.lock); */
	34	struct phonet_device_list pndevs = {
	35	.list = LIST_HEAD_INIT(pndevs.list),
	36	.lock = __SPIN_LOCK_UNLOCKED(pndevs.lock),
	37	};
	38
	39	/* Allocate new Phonet device. */
	40	static struct phonet_device __phonet_device_alloc(struct net_device dev)
	41	{
	42	struct phonet_device pnd = kmalloc(sizeof(pnd), GFP_ATOMIC);
	43	if (pnd == NULL)
	44	return NULL;
	45	pnd->netdev = dev;
	46	bitmap_zero(pnd->addrs, 64);
	47
	48	list_add(&pnd->list, &pndevs.list);
	49	return pnd;
	50	}
	51
	52	static struct phonet_device __phonet_get(struct net_device dev)
	53	{
	54	struct phonet_device *pnd;
	55
	56	list_for_each_entry(pnd, &pndevs.list, list) {
	57	if (pnd->netdev == dev)
	58	return pnd;
	59	}
	60	return NULL;
	61	}
	62
	63	static void __phonet_device_free(struct phonet_device *pnd)
	64	{
65	list_del(&pnd->list);
66	kfree(pnd);
67	}
68
69	struct net_device phonet_device_get(struct net net)
70	{
71	struct phonet_device *pnd;
72	struct net_device *dev;
73
74	spin_lock_bh(&pndevs.lock);
75	list_for_each_entry(pnd, &pndevs.list, list) {
76	dev = pnd->netdev;
77	BUG_ON(!dev);
78
79	if (dev_net(dev) == net &&
80	(dev->reg_state == NETREG_REGISTERED) &&
81	((pnd->netdev->flags & IFF_UP)) == IFF_UP)
82	break;
83	dev = NULL;
84	}
85	if (dev)
86	dev_hold(dev);
87	spin_unlock_bh(&pndevs.lock);
88	return dev;
89	}
90
91	int phonet_address_add(struct net_device *dev, u8 addr)
92	{
93	struct phonet_device *pnd;
94	int err = 0;
95
96	spin_lock_bh(&pndevs.lock);
97	/* Find or create Phonet-specific device data */
98	pnd = __phonet_get(dev);
99	if (pnd == NULL)
100	pnd = __phonet_device_alloc(dev);
101	if (unlikely(pnd == NULL))
102	err = -ENOMEM;
103	else if (test_and_set_bit(addr >> 2, pnd->addrs))
104	err = -EEXIST;
105	spin_unlock_bh(&pndevs.lock);
106	return err;
107	}
108
109	int phonet_address_del(struct net_device *dev, u8 addr)
110	{
111	struct phonet_device *pnd;
112	int err = 0;
113
114	spin_lock_bh(&pndevs.lock);
115	pnd = __phonet_get(dev);
116	if (!pnd \|\| !test_and_clear_bit(addr >> 2, pnd->addrs))
117	err = -EADDRNOTAVAIL;
7e5ab542	118	else if (bitmap_empty(pnd->addrs, 64))
f8ff6028 RDC	119	__phonet_device_free(pnd);
	120	spin_unlock_bh(&pndevs.lock);
	121	return err;
	122	}
	123
	124	/* Gets a source address toward a destination, through a interface. */
	125	u8 phonet_address_get(struct net_device *dev, u8 addr)
	126	{
	127	struct phonet_device *pnd;
	128
	129	spin_lock_bh(&pndevs.lock);
	130	pnd = __phonet_get(dev);
	131	if (pnd) {
	132	BUG_ON(bitmap_empty(pnd->addrs, 64));
	133
	134	/* Use same source address as destination, if possible */
	135	if (!test_bit(addr >> 2, pnd->addrs))
	136	addr = find_first_bit(pnd->addrs, 64) << 2;
	137	} else
	138	addr = PN_NO_ADDR;
	139	spin_unlock_bh(&pndevs.lock);
	140	return addr;
	141	}
	142
	143	int phonet_address_lookup(u8 addr)
	144	{
	145	struct phonet_device *pnd;
	146
	147	spin_lock_bh(&pndevs.lock);
	148	list_for_each_entry(pnd, &pndevs.list, list) {
	149	/* Don't allow unregistering devices! */
	150	if ((pnd->netdev->reg_state != NETREG_REGISTERED) \|\|
	151	((pnd->netdev->flags & IFF_UP)) != IFF_UP)
	152	continue;
	153
	154	if (test_bit(addr >> 2, pnd->addrs)) {
	155	spin_unlock_bh(&pndevs.lock);
	156	return 0;
	157	}
	158	}
	159	spin_unlock_bh(&pndevs.lock);
	160	return -EADDRNOTAVAIL;
	161	}
	162
	163	/* notify Phonet of device events */
	164	static int phonet_device_notify(struct notifier_block *me, unsigned long what,
	165	void *arg)
	166	{
	167	struct net_device *dev = arg;
	168
	169	if (what == NETDEV_UNREGISTER) {
	170	struct phonet_device *pnd;
	171
	172	/* Destroy phonet-specific device data */
	173	spin_lock_bh(&pndevs.lock);
	174	pnd = __phonet_get(dev);
	175	if (pnd)
	176	__phonet_device_free(pnd);
	177	spin_unlock_bh(&pndevs.lock);
	178	}
	179	return 0;
	180
	181	}
	182
183	static struct notifier_block phonet_device_notifier = {
184	.notifier_call = phonet_device_notify,
185	.priority = 0,
186	};
187
188	/* Initialize Phonet devices list */
189	void phonet_device_init(void)
190	{
191	register_netdevice_notifier(&phonet_device_notifier);
192	}
193
194	void phonet_device_exit(void)
195	{
196	struct phonet_device pnd, n;
197
198	rtnl_unregister_all(PF_PHONET);
199	rtnl_lock();
200	spin_lock_bh(&pndevs.lock);
201
202	list_for_each_entry_safe(pnd, n, &pndevs.list, list)
203	__phonet_device_free(pnd);
204
205	spin_unlock_bh(&pndevs.lock);
206	rtnl_unlock();
207	unregister_netdevice_notifier(&phonet_device_notifier);
208	}