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
);
76 err
= __dev_addr_delete(&dev
->mc_list
, &dev
->mc_count
,
80 * We have altered the list, so the card
81 * loaded filter is now wrong. Fix it
84 __dev_set_rx_mode(dev
);
86 netif_tx_unlock_bh(dev
);
91 * Add a device level multicast
94 int dev_mc_add(struct net_device
*dev
, void *addr
, int alen
, int glbl
)
98 netif_tx_lock_bh(dev
);
99 err
= __dev_addr_add(&dev
->mc_list
, &dev
->mc_count
, addr
, alen
, glbl
);
101 __dev_set_rx_mode(dev
);
102 netif_tx_unlock_bh(dev
);
107 * dev_mc_sync - Synchronize device's multicast list to another device
108 * @to: destination device
109 * @from: source device
111 * Add newly added addresses to the destination device and release
112 * addresses that have no users left. The source device must be
113 * locked by netif_tx_lock_bh.
115 * This function is intended to be called from the dev->set_multicast_list
116 * function of layered software devices.
118 int dev_mc_sync(struct net_device
*to
, struct net_device
*from
)
120 struct dev_addr_list
*da
, *next
;
123 netif_tx_lock_bh(to
);
127 if (!da
->da_synced
) {
128 err
= __dev_addr_add(&to
->mc_list
, &to
->mc_count
,
129 da
->da_addr
, da
->da_addrlen
, 0);
134 } else if (da
->da_users
== 1) {
135 __dev_addr_delete(&to
->mc_list
, &to
->mc_count
,
136 da
->da_addr
, da
->da_addrlen
, 0);
137 __dev_addr_delete(&from
->mc_list
, &from
->mc_count
,
138 da
->da_addr
, da
->da_addrlen
, 0);
143 __dev_set_rx_mode(to
);
144 netif_tx_unlock_bh(to
);
148 EXPORT_SYMBOL(dev_mc_sync
);
152 * dev_mc_unsync - Remove synchronized addresses from the destination
154 * @to: destination device
155 * @from: source device
157 * Remove all addresses that were added to the destination device by
158 * dev_mc_sync(). This function is intended to be called from the
159 * dev->stop function of layered software devices.
161 void dev_mc_unsync(struct net_device
*to
, struct net_device
*from
)
163 struct dev_addr_list
*da
, *next
;
165 netif_tx_lock_bh(from
);
166 netif_tx_lock_bh(to
);
173 __dev_addr_delete(&to
->mc_list
, &to
->mc_count
,
174 da
->da_addr
, da
->da_addrlen
, 0);
176 __dev_addr_delete(&from
->mc_list
, &from
->mc_count
,
177 da
->da_addr
, da
->da_addrlen
, 0);
180 __dev_set_rx_mode(to
);
182 netif_tx_unlock_bh(to
);
183 netif_tx_unlock_bh(from
);
185 EXPORT_SYMBOL(dev_mc_unsync
);
187 #ifdef CONFIG_PROC_FS
188 static void *dev_mc_seq_start(struct seq_file
*seq
, loff_t
*pos
)
190 struct net_device
*dev
;
193 read_lock(&dev_base_lock
);
194 for_each_netdev(dev
) {
201 static void *dev_mc_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
204 return next_net_device((struct net_device
*)v
);
207 static void dev_mc_seq_stop(struct seq_file
*seq
, void *v
)
209 read_unlock(&dev_base_lock
);
213 static int dev_mc_seq_show(struct seq_file
*seq
, void *v
)
215 struct dev_addr_list
*m
;
216 struct net_device
*dev
= v
;
218 netif_tx_lock_bh(dev
);
219 for (m
= dev
->mc_list
; m
; m
= m
->next
) {
222 seq_printf(seq
, "%-4d %-15s %-5d %-5d ", dev
->ifindex
,
223 dev
->name
, m
->dmi_users
, m
->dmi_gusers
);
225 for (i
= 0; i
< m
->dmi_addrlen
; i
++)
226 seq_printf(seq
, "%02x", m
->dmi_addr
[i
]);
230 netif_tx_unlock_bh(dev
);
234 static const struct seq_operations dev_mc_seq_ops
= {
235 .start
= dev_mc_seq_start
,
236 .next
= dev_mc_seq_next
,
237 .stop
= dev_mc_seq_stop
,
238 .show
= dev_mc_seq_show
,
241 static int dev_mc_seq_open(struct inode
*inode
, struct file
*file
)
243 return seq_open(file
, &dev_mc_seq_ops
);
246 static const struct file_operations dev_mc_seq_fops
= {
247 .owner
= THIS_MODULE
,
248 .open
= dev_mc_seq_open
,
251 .release
= seq_release
,
256 void __init
dev_mcast_init(void)
258 proc_net_fops_create(&init_net
, "dev_mcast", 0, &dev_mc_seq_fops
);
261 EXPORT_SYMBOL(dev_mc_add
);
262 EXPORT_SYMBOL(dev_mc_delete
);