diff options
Diffstat (limited to 'net/phonet/pn_dev.c')
-rw-r--r-- | net/phonet/pn_dev.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/net/phonet/pn_dev.c b/net/phonet/pn_dev.c new file mode 100644 index 0000000..53be9fc --- /dev/null +++ b/net/phonet/pn_dev.c @@ -0,0 +1,208 @@ +/* + * 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; + 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); +} |