2 * Linux NET3: Multicast List maintenance.
5 * Tim Kordas <tjk@nostromo.eeap.cwru.edu>
6 * Richard Underwood <richard@wuzz.demon.co.uk>
8 * Stir fried together from the IP multicast and CAP patches above
9 * Alan Cox <Alan.Cox@linux.org>
12 * Alan Cox : Update the device on a real delete
13 * rather than any time but...
14 * Alan Cox : IFF_ALLMULTI support.
15 * Alan Cox : New format set_multicast_list() calls.
16 * Gleb Natapov : Remove dev_mc_lock.
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
24 #include <linux/module.h>
25 #include <asm/uaccess.h>
26 #include <asm/system.h>
27 #include <linux/bitops.h>
28 #include <linux/types.h>
29 #include <linux/kernel.h>
30 #include <linux/string.h>
32 #include <linux/socket.h>
33 #include <linux/sockios.h>
35 #include <linux/errno.h>
36 #include <linux/interrupt.h>
37 #include <linux/if_ether.h>
38 #include <linux/inet.h>
39 #include <linux/netdevice.h>
40 #include <linux/etherdevice.h>
41 #include <linux/proc_fs.h>
42 #include <linux/seq_file.h>
43 #include <linux/init.h>
44 #include <net/net_namespace.h>
46 #include <net/route.h>
47 #include <linux/skbuff.h>
53 * Device multicast list maintenance.
55 * This is used both by IP and by the user level maintenance functions.
56 * Unlike BSD we maintain a usage count on a given multicast address so
57 * that a casual user application can add/delete multicasts used by
58 * protocols without doing damage to the protocols when it deletes the
59 * entries. It also helps IP as it tracks overlapping maps.
61 * Device mc lists are changed by bh at least if IPv6 is enabled,
62 * so that it must be bh protected.
64 * We block accesses to device mc filters with netif_tx_lock.
68 * Delete a device level multicast
71 int dev_mc_delete(struct net_device *dev, void *addr, int alen, int glbl)
75 netif_tx_lock_bh(dev);
77 err = __dev_addr_delete(&dev->mc_list, &dev->mc_count,
81 * We have altered the list, so the card
82 * loaded filter is now wrong. Fix it
85 __dev_set_rx_mode(dev);
87 netif_addr_unlock(dev);
88 netif_tx_unlock_bh(dev);
93 * Add a device level multicast
96 int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl)
100 netif_tx_lock_bh(dev);
101 netif_addr_lock(dev);
102 err = __dev_addr_add(&dev->mc_list, &dev->mc_count, addr, alen, glbl);
104 __dev_set_rx_mode(dev);
105 netif_addr_unlock(dev);
106 netif_tx_unlock_bh(dev);
111 * dev_mc_sync - Synchronize device's multicast list to another device
112 * @to: destination device
113 * @from: source device
115 * Add newly added addresses to the destination device and release
116 * addresses that have no users left. The source device must be
117 * locked by netif_tx_lock_bh.
119 * This function is intended to be called from the dev->set_multicast_list
120 * or dev->set_rx_mode function of layered software devices.
122 int dev_mc_sync(struct net_device *to, struct net_device *from)
126 netif_tx_lock_bh(to);
128 err = __dev_addr_sync(&to->mc_list, &to->mc_count,
129 &from->mc_list, &from->mc_count);
131 __dev_set_rx_mode(to);
132 netif_addr_unlock(to);
133 netif_tx_unlock_bh(to);
137 EXPORT_SYMBOL(dev_mc_sync);
141 * dev_mc_unsync - Remove synchronized addresses from the destination
143 * @to: destination device
144 * @from: source device
146 * Remove all addresses that were added to the destination device by
147 * dev_mc_sync(). This function is intended to be called from the
148 * dev->stop function of layered software devices.
150 void dev_mc_unsync(struct net_device *to, struct net_device *from)
152 netif_tx_lock_bh(from);
153 netif_addr_lock(from);
154 netif_tx_lock_bh(to);
157 __dev_addr_unsync(&to->mc_list, &to->mc_count,
158 &from->mc_list, &from->mc_count);
159 __dev_set_rx_mode(to);
161 netif_addr_unlock(to);
162 netif_tx_unlock_bh(to);
163 netif_addr_unlock(from);
164 netif_tx_unlock_bh(from);
166 EXPORT_SYMBOL(dev_mc_unsync);
168 #ifdef CONFIG_PROC_FS
169 static int dev_mc_seq_show(struct seq_file *seq, void *v)
171 struct dev_addr_list *m;
172 struct net_device *dev = v;
174 if (v == SEQ_START_TOKEN)
177 netif_tx_lock_bh(dev);
178 netif_addr_lock(dev);
179 for (m = dev->mc_list; m; m = m->next) {
182 seq_printf(seq, "%-4d %-15s %-5d %-5d ", dev->ifindex,
183 dev->name, m->dmi_users, m->dmi_gusers);
185 for (i = 0; i < m->dmi_addrlen; i++)
186 seq_printf(seq, "%02x", m->dmi_addr[i]);
190 netif_addr_unlock(dev);
191 netif_tx_unlock_bh(dev);
195 static const struct seq_operations dev_mc_seq_ops = {
196 .start = dev_seq_start,
197 .next = dev_seq_next,
198 .stop = dev_seq_stop,
199 .show = dev_mc_seq_show,
202 static int dev_mc_seq_open(struct inode *inode, struct file *file)
204 return seq_open_net(inode, file, &dev_mc_seq_ops,
205 sizeof(struct seq_net_private));
208 static const struct file_operations dev_mc_seq_fops = {
209 .owner = THIS_MODULE,
210 .open = dev_mc_seq_open,
213 .release = seq_release_net,
218 static int __net_init dev_mc_net_init(struct net *net)
220 if (!proc_net_fops_create(net, "dev_mcast", 0, &dev_mc_seq_fops))
225 static void __net_exit dev_mc_net_exit(struct net *net)
227 proc_net_remove(net, "dev_mcast");
230 static struct pernet_operations __net_initdata dev_mc_net_ops = {
231 .init = dev_mc_net_init,
232 .exit = dev_mc_net_exit,
235 void __init dev_mcast_init(void)
237 register_pernet_subsys(&dev_mc_net_ops);
240 EXPORT_SYMBOL(dev_mc_add);
241 EXPORT_SYMBOL(dev_mc_delete);