2 * net/tipc/eth_media.c: Ethernet bearer support for TIPC
4 * Copyright (c) 2001-2007, Ericsson AB
5 * Copyright (c) 2005-2007, Wind River Systems
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20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
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40 #define MAX_ETH_BEARERS 2
41 #define ETH_LINK_PRIORITY TIPC_DEF_LINK_PRI
42 #define ETH_LINK_TOLERANCE TIPC_DEF_LINK_TOL
43 #define ETH_LINK_WINDOW TIPC_DEF_LINK_WIN
46 * struct eth_bearer - Ethernet bearer data structure
47 * @bearer: ptr to associated "generic" bearer structure
48 * @dev: ptr to associated Ethernet network device
49 * @tipc_packet_type: used in binding TIPC to Ethernet driver
53 struct tipc_bearer *bearer;
54 struct net_device *dev;
55 struct packet_type tipc_packet_type;
58 static struct eth_bearer eth_bearers[MAX_ETH_BEARERS];
59 static int eth_started;
60 static struct notifier_block notifier;
63 * send_msg - send a TIPC message out over an Ethernet interface
66 static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
67 struct tipc_media_addr *dest)
69 struct sk_buff *clone;
70 struct net_device *dev;
73 clone = skb_clone(buf, GFP_ATOMIC);
77 dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
78 delta = dev->hard_header_len - skb_headroom(buf);
81 pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
86 skb_reset_network_header(clone);
88 dev_hard_header(clone, dev, ETH_P_TIPC, &dest->dev_addr.eth_addr,
89 dev->dev_addr, clone->len);
90 dev_queue_xmit(clone);
95 * recv_msg - handle incoming TIPC message from an Ethernet interface
97 * Accept only packets explicitly sent to this node, or broadcast packets;
98 * ignores packets sent using Ethernet multicast, and traffic sent to other
99 * nodes (which can happen if interface is running in promiscuous mode).
102 static int recv_msg(struct sk_buff *buf, struct net_device *dev,
103 struct packet_type *pt, struct net_device *orig_dev)
105 struct eth_bearer *eb_ptr = (struct eth_bearer *)pt->af_packet_priv;
107 if (!net_eq(dev_net(dev), &init_net)) {
112 if (likely(eb_ptr->bearer)) {
113 if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
115 tipc_recv_msg(buf, eb_ptr->bearer);
124 * enable_bearer - attach TIPC bearer to an Ethernet interface
127 static int enable_bearer(struct tipc_bearer *tb_ptr)
129 struct net_device *dev = NULL;
130 struct net_device *pdev = NULL;
131 struct eth_bearer *eb_ptr = ð_bearers[0];
132 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
133 char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;
136 /* Find unused Ethernet bearer structure */
138 while (eb_ptr->dev) {
141 if (++eb_ptr == stop)
142 return pending_dev ? -EAGAIN : -EDQUOT;
145 /* Find device with specified name */
147 for_each_netdev(&init_net, pdev) {
148 if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
156 /* Find Ethernet bearer for device (or create one) */
158 while ((eb_ptr != stop) && eb_ptr->dev && (eb_ptr->dev != dev))
164 eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
165 eb_ptr->tipc_packet_type.dev = dev;
166 eb_ptr->tipc_packet_type.func = recv_msg;
167 eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
168 INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
170 dev_add_pack(&eb_ptr->tipc_packet_type);
173 /* Associate TIPC bearer with Ethernet bearer */
175 eb_ptr->bearer = tb_ptr;
176 tb_ptr->usr_handle = (void *)eb_ptr;
177 tb_ptr->mtu = dev->mtu;
179 tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
180 memcpy(&tb_ptr->addr.dev_addr, dev->dev_addr, ETH_ALEN);
185 * disable_bearer - detach TIPC bearer from an Ethernet interface
187 * We really should do dev_remove_pack() here, but this function can not be
188 * called at tasklet level. => Use eth_bearer->bearer as a flag to throw away
189 * incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit.
192 static void disable_bearer(struct tipc_bearer *tb_ptr)
194 ((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL;
198 * recv_notification - handle device updates from OS
200 * Change the state of the Ethernet bearer (if any) associated with the
204 static int recv_notification(struct notifier_block *nb, unsigned long evt,
207 struct net_device *dev = (struct net_device *)dv;
208 struct eth_bearer *eb_ptr = ð_bearers[0];
209 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
211 if (!net_eq(dev_net(dev), &init_net))
214 while ((eb_ptr->dev != dev)) {
215 if (++eb_ptr == stop)
216 return NOTIFY_DONE; /* couldn't find device */
219 return NOTIFY_DONE; /* bearer had been disabled */
221 eb_ptr->bearer->mtu = dev->mtu;
225 if (netif_carrier_ok(dev))
226 tipc_continue(eb_ptr->bearer);
228 tipc_block_bearer(eb_ptr->bearer->name);
231 tipc_continue(eb_ptr->bearer);
234 tipc_block_bearer(eb_ptr->bearer->name);
236 case NETDEV_CHANGEMTU:
237 case NETDEV_CHANGEADDR:
238 tipc_block_bearer(eb_ptr->bearer->name);
239 tipc_continue(eb_ptr->bearer);
241 case NETDEV_UNREGISTER:
242 case NETDEV_CHANGENAME:
243 tipc_disable_bearer(eb_ptr->bearer->name);
250 * eth_addr2str - convert Ethernet address to string
253 static char *eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
255 unchar *addr = (unchar *)&a->dev_addr;
260 sprintf(str_buf, "%pM", addr);
265 * tipc_eth_media_start - activate Ethernet bearer support
267 * Register Ethernet media type with TIPC bearer code. Also register
268 * with OS for notifications about device state changes.
271 int tipc_eth_media_start(void)
273 struct tipc_media_addr bcast_addr;
279 bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
280 memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN);
282 memset(eth_bearers, 0, sizeof(eth_bearers));
284 res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth",
285 enable_bearer, disable_bearer, send_msg,
286 eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY,
287 ETH_LINK_TOLERANCE, ETH_LINK_WINDOW);
291 notifier.notifier_call = &recv_notification;
292 notifier.priority = 0;
293 res = register_netdevice_notifier(¬ifier);
300 * tipc_eth_media_stop - deactivate Ethernet bearer support
303 void tipc_eth_media_stop(void)
310 unregister_netdevice_notifier(¬ifier);
311 for (i = 0; i < MAX_ETH_BEARERS ; i++) {
312 if (eth_bearers[i].bearer) {
313 eth_bearers[i].bearer->blocked = 1;
314 eth_bearers[i].bearer = NULL;
316 if (eth_bearers[i].dev) {
317 dev_remove_pack(ð_bearers[i].tipc_packet_type);
318 dev_put(eth_bearers[i].dev);
321 memset(ð_bearers, 0, sizeof(eth_bearers));