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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21 * GNU General Public License ("GPL") version 2 as published by the Free
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40 #define MAX_ETH_BEARERS MAX_BEARERS
42 #define ETH_ADDR_OFFSET 4 /* message header offset of MAC address */
45 * struct eth_bearer - Ethernet bearer data structure
46 * @bearer: ptr to associated "generic" bearer structure
47 * @dev: ptr to associated Ethernet network device
48 * @tipc_packet_type: used in binding TIPC to Ethernet driver
49 * @setup: work item used when enabling bearer
50 * @cleanup: work item used when disabling bearer
53 struct tipc_bearer *bearer;
54 struct net_device *dev;
55 struct packet_type tipc_packet_type;
56 struct work_struct setup;
57 struct work_struct cleanup;
60 static struct tipc_media eth_media_info;
61 static struct eth_bearer eth_bearers[MAX_ETH_BEARERS];
62 static int eth_started;
64 static int recv_notification(struct notifier_block *nb, unsigned long evt,
67 * Network device notifier info
69 static struct notifier_block notifier = {
70 .notifier_call = recv_notification,
75 * eth_media_addr_set - initialize Ethernet media address structure
77 * Media-dependent "value" field stores MAC address in first 6 bytes
78 * and zeroes out the remaining bytes.
80 static void eth_media_addr_set(const struct tipc_bearer *tb_ptr,
81 struct tipc_media_addr *a, char *mac)
83 memcpy(a->value, mac, ETH_ALEN);
84 memset(a->value + ETH_ALEN, 0, sizeof(a->value) - ETH_ALEN);
85 a->media_id = TIPC_MEDIA_TYPE_ETH;
86 a->broadcast = !memcmp(mac, tb_ptr->bcast_addr.value, ETH_ALEN);
90 * send_msg - send a TIPC message out over an Ethernet interface
92 static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
93 struct tipc_media_addr *dest)
95 struct sk_buff *clone;
96 struct net_device *dev;
99 clone = skb_clone(buf, GFP_ATOMIC);
103 dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
104 delta = dev->hard_header_len - skb_headroom(buf);
107 pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
112 skb_reset_network_header(clone);
114 clone->protocol = htons(ETH_P_TIPC);
115 dev_hard_header(clone, dev, ETH_P_TIPC, dest->value,
116 dev->dev_addr, clone->len);
117 dev_queue_xmit(clone);
122 * recv_msg - handle incoming TIPC message from an Ethernet interface
124 * Accept only packets explicitly sent to this node, or broadcast packets;
125 * ignores packets sent using Ethernet multicast, and traffic sent to other
126 * nodes (which can happen if interface is running in promiscuous mode).
128 static int recv_msg(struct sk_buff *buf, struct net_device *dev,
129 struct packet_type *pt, struct net_device *orig_dev)
131 struct eth_bearer *eb_ptr = (struct eth_bearer *)pt->af_packet_priv;
133 if (!net_eq(dev_net(dev), &init_net)) {
138 if (likely(eb_ptr->bearer)) {
139 if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
141 tipc_recv_msg(buf, eb_ptr->bearer);
150 * setup_bearer - setup association between Ethernet bearer and interface
152 static void setup_bearer(struct work_struct *work)
154 struct eth_bearer *eb_ptr =
155 container_of(work, struct eth_bearer, setup);
157 dev_add_pack(&eb_ptr->tipc_packet_type);
161 * enable_bearer - attach TIPC bearer to an Ethernet interface
163 static int enable_bearer(struct tipc_bearer *tb_ptr)
165 struct net_device *dev;
166 struct eth_bearer *eb_ptr = ð_bearers[0];
167 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
168 char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;
171 /* Find unused Ethernet bearer structure */
172 while (eb_ptr->dev) {
175 if (++eb_ptr == stop)
176 return pending_dev ? -EAGAIN : -EDQUOT;
179 /* Find device with specified name */
180 dev = dev_get_by_name(&init_net, driver_name);
184 /* Create Ethernet bearer for device */
186 eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
187 eb_ptr->tipc_packet_type.dev = dev;
188 eb_ptr->tipc_packet_type.func = recv_msg;
189 eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
190 INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
191 INIT_WORK(&eb_ptr->setup, setup_bearer);
192 schedule_work(&eb_ptr->setup);
194 /* Associate TIPC bearer with Ethernet bearer */
195 eb_ptr->bearer = tb_ptr;
196 tb_ptr->usr_handle = (void *)eb_ptr;
197 memset(tb_ptr->bcast_addr.value, 0, sizeof(tb_ptr->bcast_addr.value));
198 memcpy(tb_ptr->bcast_addr.value, dev->broadcast, ETH_ALEN);
199 tb_ptr->bcast_addr.media_id = TIPC_MEDIA_TYPE_ETH;
200 tb_ptr->bcast_addr.broadcast = 1;
201 tb_ptr->mtu = dev->mtu;
203 eth_media_addr_set(tb_ptr, &tb_ptr->addr, (char *)dev->dev_addr);
208 * cleanup_bearer - break association between Ethernet bearer and interface
210 * This routine must be invoked from a work queue because it can sleep.
212 static void cleanup_bearer(struct work_struct *work)
214 struct eth_bearer *eb_ptr =
215 container_of(work, struct eth_bearer, cleanup);
217 dev_remove_pack(&eb_ptr->tipc_packet_type);
218 dev_put(eb_ptr->dev);
223 * disable_bearer - detach TIPC bearer from an Ethernet interface
225 * Mark Ethernet bearer as inactive so that incoming buffers are thrown away,
226 * then get worker thread to complete bearer cleanup. (Can't do cleanup
227 * here because cleanup code needs to sleep and caller holds spinlocks.)
229 static void disable_bearer(struct tipc_bearer *tb_ptr)
231 struct eth_bearer *eb_ptr = (struct eth_bearer *)tb_ptr->usr_handle;
233 eb_ptr->bearer = NULL;
234 INIT_WORK(&eb_ptr->cleanup, cleanup_bearer);
235 schedule_work(&eb_ptr->cleanup);
239 * recv_notification - handle device updates from OS
241 * Change the state of the Ethernet bearer (if any) associated with the
244 static int recv_notification(struct notifier_block *nb, unsigned long evt,
247 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
248 struct eth_bearer *eb_ptr = ð_bearers[0];
249 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
251 if (!net_eq(dev_net(dev), &init_net))
254 while ((eb_ptr->dev != dev)) {
255 if (++eb_ptr == stop)
256 return NOTIFY_DONE; /* couldn't find device */
259 return NOTIFY_DONE; /* bearer had been disabled */
261 eb_ptr->bearer->mtu = dev->mtu;
265 if (netif_carrier_ok(dev))
266 tipc_continue(eb_ptr->bearer);
268 tipc_block_bearer(eb_ptr->bearer->name);
271 tipc_continue(eb_ptr->bearer);
274 tipc_block_bearer(eb_ptr->bearer->name);
276 case NETDEV_CHANGEMTU:
277 case NETDEV_CHANGEADDR:
278 tipc_block_bearer(eb_ptr->bearer->name);
279 tipc_continue(eb_ptr->bearer);
281 case NETDEV_UNREGISTER:
282 case NETDEV_CHANGENAME:
283 tipc_disable_bearer(eb_ptr->bearer->name);
290 * eth_addr2str - convert Ethernet address to string
292 static int eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
294 if (str_size < 18) /* 18 = strlen("aa:bb:cc:dd:ee:ff\0") */
297 sprintf(str_buf, "%pM", a->value);
302 * eth_str2addr - convert Ethernet address format to message header format
304 static int eth_addr2msg(struct tipc_media_addr *a, char *msg_area)
306 memset(msg_area, 0, TIPC_MEDIA_ADDR_SIZE);
307 msg_area[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_ETH;
308 memcpy(msg_area + ETH_ADDR_OFFSET, a->value, ETH_ALEN);
313 * eth_str2addr - convert message header address format to Ethernet format
315 static int eth_msg2addr(const struct tipc_bearer *tb_ptr,
316 struct tipc_media_addr *a, char *msg_area)
318 if (msg_area[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_ETH)
321 eth_media_addr_set(tb_ptr, a, msg_area + ETH_ADDR_OFFSET);
326 * Ethernet media registration info
328 static struct tipc_media eth_media_info = {
329 .send_msg = send_msg,
330 .enable_bearer = enable_bearer,
331 .disable_bearer = disable_bearer,
332 .addr2str = eth_addr2str,
333 .addr2msg = eth_addr2msg,
334 .msg2addr = eth_msg2addr,
335 .priority = TIPC_DEF_LINK_PRI,
336 .tolerance = TIPC_DEF_LINK_TOL,
337 .window = TIPC_DEF_LINK_WIN,
338 .type_id = TIPC_MEDIA_TYPE_ETH,
343 * tipc_eth_media_start - activate Ethernet bearer support
345 * Register Ethernet media type with TIPC bearer code. Also register
346 * with OS for notifications about device state changes.
348 int tipc_eth_media_start(void)
355 res = tipc_register_media(ð_media_info);
359 res = register_netdevice_notifier(¬ifier);
366 * tipc_eth_media_stop - deactivate Ethernet bearer support
368 void tipc_eth_media_stop(void)
373 flush_scheduled_work();
374 unregister_netdevice_notifier(¬ifier);