/* * 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); }