2 * Copyright (C) ST-Ericsson AB 2010
3 * Authors: Sjur Brendeland
5 * License terms: GNU General Public License (GPL) version 2
8 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
11 #include <linux/hardirq.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <linux/if_ether.h>
17 #include <linux/sched.h>
18 #include <linux/sockios.h>
19 #include <linux/caif/if_caif.h>
20 #include <net/rtnetlink.h>
21 #include <net/caif/caif_layer.h>
22 #include <net/caif/cfpkt.h>
23 #include <net/caif/caif_dev.h>
25 /* GPRS PDP connection has MTU to 1500 */
26 #define GPRS_PDP_MTU 1500
27 /* 5 sec. connect timeout */
28 #define CONNECT_TIMEOUT (5 * HZ)
29 #define CAIF_NET_DEFAULT_QUEUE_LEN 500
30 #define UNDEF_CONNID 0xffffffff
32 /*This list is protected by the rtnl lock. */
33 static LIST_HEAD(chnl_net_list);
35 MODULE_LICENSE("GPL");
36 MODULE_ALIAS_RTNL_LINK("caif");
47 struct net_device_stats stats;
48 struct caif_connect_request conn_req;
49 struct list_head list_field;
50 struct net_device *netdev;
52 wait_queue_head_t netmgmt_wq;
53 /* Flow status to remember and control the transmission. */
55 enum caif_states state;
58 static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
61 struct chnl_net *priv;
66 priv = container_of(layr, struct chnl_net, chnl);
70 skb = (struct sk_buff *) cfpkt_tonative(pkt);
72 /* Get length of CAIF packet. */
75 /* Pass some minimum information and
76 * send the packet to the net stack.
78 skb->dev = priv->netdev;
80 /* check the version of IP */
81 ip_version = skb_header_pointer(skb, 0, 1, &buf);
87 switch (*ip_version >> 4) {
89 skb->protocol = htons(ETH_P_IP);
92 skb->protocol = htons(ETH_P_IPV6);
96 priv->netdev->stats.rx_errors++;
100 /* If we change the header in loop mode, the checksum is corrupted. */
101 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
102 skb->ip_summed = CHECKSUM_UNNECESSARY;
104 skb->ip_summed = CHECKSUM_NONE;
111 /* Update statistics. */
112 priv->netdev->stats.rx_packets++;
113 priv->netdev->stats.rx_bytes += pktlen;
118 static int delete_device(struct chnl_net *dev)
122 unregister_netdevice(dev->netdev);
126 static void close_work(struct work_struct *work)
128 struct chnl_net *dev = NULL;
129 struct list_head *list_node;
130 struct list_head *_tmp;
133 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
134 dev = list_entry(list_node, struct chnl_net, list_field);
135 if (dev->state == CAIF_SHUTDOWN)
136 dev_close(dev->netdev);
140 static DECLARE_WORK(close_worker, close_work);
142 static void chnl_hold(struct cflayer *lyr)
144 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
145 dev_hold(priv->netdev);
148 static void chnl_put(struct cflayer *lyr)
150 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
151 dev_put(priv->netdev);
154 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
157 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
158 pr_debug("NET flowctrl func called flow: %s\n",
159 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
160 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
161 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
162 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
163 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
164 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
165 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
170 case CAIF_CTRLCMD_FLOW_OFF_IND:
171 priv->flowenabled = false;
172 netif_stop_queue(priv->netdev);
174 case CAIF_CTRLCMD_DEINIT_RSP:
175 priv->state = CAIF_DISCONNECTED;
177 case CAIF_CTRLCMD_INIT_FAIL_RSP:
178 priv->state = CAIF_DISCONNECTED;
179 wake_up_interruptible(&priv->netmgmt_wq);
181 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
182 priv->state = CAIF_SHUTDOWN;
183 netif_tx_disable(priv->netdev);
184 schedule_work(&close_worker);
186 case CAIF_CTRLCMD_FLOW_ON_IND:
187 priv->flowenabled = true;
188 netif_wake_queue(priv->netdev);
190 case CAIF_CTRLCMD_INIT_RSP:
191 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
192 priv->state = CAIF_CONNECTED;
193 priv->flowenabled = true;
194 netif_wake_queue(priv->netdev);
195 wake_up_interruptible(&priv->netmgmt_wq);
202 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
204 struct chnl_net *priv;
205 struct cfpkt *pkt = NULL;
208 /* Get our private data. */
209 priv = netdev_priv(dev);
211 if (skb->len > priv->netdev->mtu) {
212 pr_warn("Size of skb exceeded MTU\n");
214 dev->stats.tx_errors++;
218 if (!priv->flowenabled) {
219 pr_debug("dropping packets flow off\n");
221 dev->stats.tx_dropped++;
225 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
226 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
228 /* Store original SKB length. */
231 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
233 /* Send the packet down the stack. */
234 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
236 dev->stats.tx_dropped++;
240 /* Update statistics. */
241 dev->stats.tx_packets++;
242 dev->stats.tx_bytes += len;
247 static int chnl_net_open(struct net_device *dev)
249 struct chnl_net *priv = NULL;
251 int llifindex, headroom, tailroom, mtu;
252 struct net_device *lldev;
254 priv = netdev_priv(dev);
256 pr_debug("chnl_net_open: no priv\n");
260 if (priv->state != CAIF_CONNECTING) {
261 priv->state = CAIF_CONNECTING;
262 result = caif_connect_client(dev_net(dev), &priv->conn_req,
263 &priv->chnl, &llifindex,
264 &headroom, &tailroom);
267 "Unable to register and open device,"
273 lldev = __dev_get_by_index(dev_net(dev), llifindex);
276 pr_debug("no interface?\n");
281 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
282 dev->hard_header_len = headroom + lldev->hard_header_len +
283 lldev->needed_tailroom;
286 * MTU, head-room etc is not know before we have a
287 * CAIF link layer device available. MTU calculation may
288 * override initial RTNL configuration.
289 * MTU is minimum of current mtu, link layer mtu pluss
290 * CAIF head and tail, and PDP GPRS contexts max MTU.
292 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
293 mtu = min_t(int, GPRS_PDP_MTU, mtu);
294 dev_set_mtu(dev, mtu);
297 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
303 rtnl_unlock(); /* Release RTNL lock during connect wait */
305 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
306 priv->state != CAIF_CONNECTING,
311 if (result == -ERESTARTSYS) {
312 pr_debug("wait_event_interruptible woken by a signal\n");
313 result = -ERESTARTSYS;
318 pr_debug("connect timeout\n");
319 caif_disconnect_client(dev_net(dev), &priv->chnl);
320 priv->state = CAIF_DISCONNECTED;
321 pr_debug("state disconnected\n");
326 if (priv->state != CAIF_CONNECTED) {
327 pr_debug("connect failed\n");
328 result = -ECONNREFUSED;
331 pr_debug("CAIF Netdevice connected\n");
335 caif_disconnect_client(dev_net(dev), &priv->chnl);
336 priv->state = CAIF_DISCONNECTED;
337 pr_debug("state disconnected\n");
342 static int chnl_net_stop(struct net_device *dev)
344 struct chnl_net *priv;
347 priv = netdev_priv(dev);
348 priv->state = CAIF_DISCONNECTED;
349 caif_disconnect_client(dev_net(dev), &priv->chnl);
353 static int chnl_net_init(struct net_device *dev)
355 struct chnl_net *priv;
357 priv = netdev_priv(dev);
358 strncpy(priv->name, dev->name, sizeof(priv->name));
359 INIT_LIST_HEAD(&priv->list_field);
363 static void chnl_net_uninit(struct net_device *dev)
365 struct chnl_net *priv;
367 priv = netdev_priv(dev);
368 list_del_init(&priv->list_field);
371 static const struct net_device_ops netdev_ops = {
372 .ndo_open = chnl_net_open,
373 .ndo_stop = chnl_net_stop,
374 .ndo_init = chnl_net_init,
375 .ndo_uninit = chnl_net_uninit,
376 .ndo_start_xmit = chnl_net_start_xmit,
379 static void chnl_net_destructor(struct net_device *dev)
381 struct chnl_net *priv = netdev_priv(dev);
382 caif_free_client(&priv->chnl);
386 static void ipcaif_net_setup(struct net_device *dev)
388 struct chnl_net *priv;
389 dev->netdev_ops = &netdev_ops;
390 dev->destructor = chnl_net_destructor;
391 dev->flags |= IFF_NOARP;
392 dev->flags |= IFF_POINTOPOINT;
393 dev->mtu = GPRS_PDP_MTU;
394 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
396 priv = netdev_priv(dev);
397 priv->chnl.receive = chnl_recv_cb;
398 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
400 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
401 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
402 priv->conn_req.priority = CAIF_PRIO_LOW;
403 /* Insert illegal value */
404 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
405 priv->flowenabled = false;
407 init_waitqueue_head(&priv->netmgmt_wq);
411 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
413 struct chnl_net *priv;
415 priv = netdev_priv(dev);
416 if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
417 priv->conn_req.sockaddr.u.dgm.connection_id) ||
418 nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
419 priv->conn_req.sockaddr.u.dgm.connection_id))
420 goto nla_put_failure;
421 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
422 if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
423 goto nla_put_failure;
430 static void caif_netlink_parms(struct nlattr *data[],
431 struct caif_connect_request *conn_req)
434 pr_warn("no params data found\n");
437 if (data[IFLA_CAIF_IPV4_CONNID])
438 conn_req->sockaddr.u.dgm.connection_id =
439 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
440 if (data[IFLA_CAIF_IPV6_CONNID])
441 conn_req->sockaddr.u.dgm.connection_id =
442 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
443 if (data[IFLA_CAIF_LOOPBACK]) {
444 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
445 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
447 conn_req->protocol = CAIFPROTO_DATAGRAM;
451 static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
452 struct nlattr *tb[], struct nlattr *data[])
455 struct chnl_net *caifdev;
457 caifdev = netdev_priv(dev);
458 caif_netlink_parms(data, &caifdev->conn_req);
460 ret = register_netdevice(dev);
462 pr_warn("device rtml registration failed\n");
464 list_add(&caifdev->list_field, &chnl_net_list);
466 /* Use ifindex as connection id, and use loopback channel default. */
467 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
468 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
469 caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
474 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
475 struct nlattr *data[])
477 struct chnl_net *caifdev;
479 caifdev = netdev_priv(dev);
480 caif_netlink_parms(data, &caifdev->conn_req);
481 netdev_state_change(dev);
485 static size_t ipcaif_get_size(const struct net_device *dev)
488 /* IFLA_CAIF_IPV4_CONNID */
490 /* IFLA_CAIF_IPV6_CONNID */
492 /* IFLA_CAIF_LOOPBACK */
497 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
498 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
499 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
500 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
504 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
506 .priv_size = sizeof(struct chnl_net),
507 .setup = ipcaif_net_setup,
508 .maxtype = IFLA_CAIF_MAX,
509 .policy = ipcaif_policy,
510 .newlink = ipcaif_newlink,
511 .changelink = ipcaif_changelink,
512 .get_size = ipcaif_get_size,
513 .fill_info = ipcaif_fill_info,
517 static int __init chnl_init_module(void)
519 return rtnl_link_register(&ipcaif_link_ops);
522 static void __exit chnl_exit_module(void)
524 struct chnl_net *dev = NULL;
525 struct list_head *list_node;
526 struct list_head *_tmp;
527 rtnl_link_unregister(&ipcaif_link_ops);
529 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
530 dev = list_entry(list_node, struct chnl_net, list_field);
531 list_del_init(list_node);
537 module_init(chnl_init_module);
538 module_exit(chnl_exit_module);