/*
* 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/netns/generic.h>
#include <net/phonet/pn_dev.h>
struct phonet_net {
struct phonet_device_list pndevs;
};
int phonet_net_id;
struct phonet_device_list *phonet_device_list(struct net *net)
{
struct phonet_net *pnn = net_generic(net, phonet_net_id);
return &pnn->pndevs;
}
/* Allocate new Phonet device. */
static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
{
struct phonet_device_list *pndevs = phonet_device_list(dev_net(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_list *pndevs = phonet_device_list(dev_net(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_list *pndevs = phonet_device_list(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->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_list *pndevs = phonet_device_list(dev_net(dev));
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_list *pndevs = phonet_device_list(dev_net(dev));
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_list *pndevs = phonet_device_list(dev_net(dev));
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(struct net *net, u8 addr)
{
struct phonet_device_list *pndevs = phonet_device_list(net);
struct phonet_device *pnd;
int err = -EADDRNOTAVAIL;
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)) {
err = 0;
goto found;
}
}
found:
spin_unlock_bh(&pndevs->lock);
return err;
}
/* 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_list *pndevs;
struct phonet_device *pnd;
/* Destroy phonet-specific device data */
pndevs = phonet_device_list(dev_net(dev));
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,
};
/* Per-namespace Phonet devices handling */
static int phonet_init_net(struct net *net)
{
struct phonet_net *pnn = kmalloc(sizeof(*pnn), GFP_KERNEL);
if (!pnn)
return -ENOMEM;
INIT_LIST_HEAD(&pnn->pndevs.list);
spin_lock_init(&pnn->pndevs.lock);
net_assign_generic(net, phonet_net_id, pnn);
return 0;
}
static void phonet_exit_net(struct net *net)
{
struct phonet_net *pnn = net_generic(net, phonet_net_id);
struct phonet_device *pnd, *n;
list_for_each_entry_safe(pnd, n, &pnn->pndevs.list, list)
__phonet_device_free(pnd);
kfree(pnn);
}
static struct pernet_operations phonet_net_ops = {
.init = phonet_init_net,
.exit = phonet_exit_net,
};
/* Initialize Phonet devices list */
int __init phonet_device_init(void)
{
int err = register_pernet_gen_device(&phonet_net_id, &phonet_net_ops);
if (err)
return err;
register_netdevice_notifier(&phonet_device_notifier);
err = phonet_netlink_register();
if (err)
phonet_device_exit();
return err;
}
void phonet_device_exit(void)
{
rtnl_unregister_all(PF_PHONET);
unregister_netdevice_notifier(&phonet_device_notifier);
unregister_pernet_gen_device(phonet_net_id, &phonet_net_ops);
}
