2 * net/tipc/eth_media.c: Ethernet bearer support for TIPC
4 * Copyright (c) 2001-2007, Ericsson AB
5 * Copyright (c) 2005-2008, 2011, 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 MAX_BEARERS
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 read_lock(&dev_base_lock);
148 for_each_netdev(&init_net, pdev) {
149 if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
155 read_unlock(&dev_base_lock);
159 /* Create Ethernet bearer for device */
162 eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
163 eb_ptr->tipc_packet_type.dev = dev;
164 eb_ptr->tipc_packet_type.func = recv_msg;
165 eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
166 INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
167 dev_add_pack(&eb_ptr->tipc_packet_type);
169 /* Associate TIPC bearer with Ethernet bearer */
171 eb_ptr->bearer = tb_ptr;
172 tb_ptr->usr_handle = (void *)eb_ptr;
173 tb_ptr->mtu = dev->mtu;
175 tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
176 memcpy(&tb_ptr->addr.dev_addr, dev->dev_addr, ETH_ALEN);
181 * disable_bearer - detach TIPC bearer from an Ethernet interface
183 * We really should do dev_remove_pack() here, but this function can not be
184 * called at tasklet level. => Use eth_bearer->bearer as a flag to throw away
185 * incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit.
188 static void disable_bearer(struct tipc_bearer *tb_ptr)
190 ((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL;
194 * recv_notification - handle device updates from OS
196 * Change the state of the Ethernet bearer (if any) associated with the
200 static int recv_notification(struct notifier_block *nb, unsigned long evt,
203 struct net_device *dev = (struct net_device *)dv;
204 struct eth_bearer *eb_ptr = ð_bearers[0];
205 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
207 if (!net_eq(dev_net(dev), &init_net))
210 while ((eb_ptr->dev != dev)) {
211 if (++eb_ptr == stop)
212 return NOTIFY_DONE; /* couldn't find device */
215 return NOTIFY_DONE; /* bearer had been disabled */
217 eb_ptr->bearer->mtu = dev->mtu;
221 if (netif_carrier_ok(dev))
222 tipc_continue(eb_ptr->bearer);
224 tipc_block_bearer(eb_ptr->bearer->name);
227 tipc_continue(eb_ptr->bearer);
230 tipc_block_bearer(eb_ptr->bearer->name);
232 case NETDEV_CHANGEMTU:
233 case NETDEV_CHANGEADDR:
234 tipc_block_bearer(eb_ptr->bearer->name);
235 tipc_continue(eb_ptr->bearer);
237 case NETDEV_UNREGISTER:
238 case NETDEV_CHANGENAME:
239 tipc_disable_bearer(eb_ptr->bearer->name);
246 * eth_addr2str - convert Ethernet address to string
249 static char *eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
251 unchar *addr = (unchar *)&a->dev_addr;
256 sprintf(str_buf, "%pM", addr);
261 * tipc_eth_media_start - activate Ethernet bearer support
263 * Register Ethernet media type with TIPC bearer code. Also register
264 * with OS for notifications about device state changes.
267 int tipc_eth_media_start(void)
269 struct tipc_media_addr bcast_addr;
275 bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
276 memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN);
278 memset(eth_bearers, 0, sizeof(eth_bearers));
280 res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth",
281 enable_bearer, disable_bearer, send_msg,
282 eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY,
283 ETH_LINK_TOLERANCE, ETH_LINK_WINDOW);
287 notifier.notifier_call = &recv_notification;
288 notifier.priority = 0;
289 res = register_netdevice_notifier(¬ifier);
296 * tipc_eth_media_stop - deactivate Ethernet bearer support
299 void tipc_eth_media_stop(void)
306 unregister_netdevice_notifier(¬ifier);
307 for (i = 0; i < MAX_ETH_BEARERS ; i++) {
308 if (eth_bearers[i].bearer) {
309 eth_bearers[i].bearer->blocked = 1;
310 eth_bearers[i].bearer = NULL;
312 if (eth_bearers[i].dev) {
313 dev_remove_pack(ð_bearers[i].tipc_packet_type);
314 dev_put(eth_bearers[i].dev);
317 memset(ð_bearers, 0, sizeof(eth_bearers));