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>
16 #include <linux/moduleparam.h>
18 #include <linux/sched.h>
19 #include <linux/sockios.h>
20 #include <linux/caif/if_caif.h>
21 #include <net/rtnetlink.h>
22 #include <net/caif/caif_layer.h>
23 #include <net/caif/cfpkt.h>
24 #include <net/caif/caif_dev.h>
26 /* GPRS PDP connection has MTU to 1500 */
27 #define GPRS_PDP_MTU 1500
28 /* 5 sec. connect timeout */
29 #define CONNECT_TIMEOUT (5 * HZ)
30 #define CAIF_NET_DEFAULT_QUEUE_LEN 500
31 #define UNDEF_CONNID 0xffffffff
33 /*This list is protected by the rtnl lock. */
34 static LIST_HEAD(chnl_net_list);
36 MODULE_LICENSE("GPL");
37 MODULE_ALIAS_RTNL_LINK("caif");
48 struct net_device_stats stats;
49 struct caif_connect_request conn_req;
50 struct list_head list_field;
51 struct net_device *netdev;
53 wait_queue_head_t netmgmt_wq;
54 /* Flow status to remember and control the transmission. */
56 enum caif_states state;
59 static void robust_list_del(struct list_head *delete_node)
61 struct list_head *list_node;
64 list_for_each_safe(list_node, n, &chnl_net_list) {
65 if (list_node == delete_node) {
73 static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
76 struct chnl_net *priv;
81 priv = container_of(layr, struct chnl_net, chnl);
85 skb = (struct sk_buff *) cfpkt_tonative(pkt);
87 /* Get length of CAIF packet. */
90 /* Pass some minimum information and
91 * send the packet to the net stack.
93 skb->dev = priv->netdev;
95 /* check the version of IP */
96 ip_version = skb_header_pointer(skb, 0, 1, &buf);
102 switch (*ip_version >> 4) {
104 skb->protocol = htons(ETH_P_IP);
107 skb->protocol = htons(ETH_P_IPV6);
111 priv->netdev->stats.rx_errors++;
115 /* If we change the header in loop mode, the checksum is corrupted. */
116 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
117 skb->ip_summed = CHECKSUM_UNNECESSARY;
119 skb->ip_summed = CHECKSUM_NONE;
126 /* Update statistics. */
127 priv->netdev->stats.rx_packets++;
128 priv->netdev->stats.rx_bytes += pktlen;
133 static int delete_device(struct chnl_net *dev)
137 unregister_netdevice(dev->netdev);
141 static void close_work(struct work_struct *work)
143 struct chnl_net *dev = NULL;
144 struct list_head *list_node;
145 struct list_head *_tmp;
148 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
149 dev = list_entry(list_node, struct chnl_net, list_field);
150 if (dev->state == CAIF_SHUTDOWN)
151 dev_close(dev->netdev);
155 static DECLARE_WORK(close_worker, close_work);
157 static void chnl_hold(struct cflayer *lyr)
159 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
160 dev_hold(priv->netdev);
163 static void chnl_put(struct cflayer *lyr)
165 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
166 dev_put(priv->netdev);
169 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
172 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
173 pr_debug("NET flowctrl func called flow: %s\n",
174 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
175 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
176 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
177 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
178 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
179 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
180 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
185 case CAIF_CTRLCMD_FLOW_OFF_IND:
186 priv->flowenabled = false;
187 netif_stop_queue(priv->netdev);
189 case CAIF_CTRLCMD_DEINIT_RSP:
190 priv->state = CAIF_DISCONNECTED;
192 case CAIF_CTRLCMD_INIT_FAIL_RSP:
193 priv->state = CAIF_DISCONNECTED;
194 wake_up_interruptible(&priv->netmgmt_wq);
196 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
197 priv->state = CAIF_SHUTDOWN;
198 netif_tx_disable(priv->netdev);
199 schedule_work(&close_worker);
201 case CAIF_CTRLCMD_FLOW_ON_IND:
202 priv->flowenabled = true;
203 netif_wake_queue(priv->netdev);
205 case CAIF_CTRLCMD_INIT_RSP:
206 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
207 priv->state = CAIF_CONNECTED;
208 priv->flowenabled = true;
209 netif_wake_queue(priv->netdev);
210 wake_up_interruptible(&priv->netmgmt_wq);
217 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
219 struct chnl_net *priv;
220 struct cfpkt *pkt = NULL;
223 /* Get our private data. */
224 priv = netdev_priv(dev);
226 if (skb->len > priv->netdev->mtu) {
227 pr_warn("Size of skb exceeded MTU\n");
229 dev->stats.tx_errors++;
233 if (!priv->flowenabled) {
234 pr_debug("dropping packets flow off\n");
236 dev->stats.tx_dropped++;
240 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
241 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
243 /* Store original SKB length. */
246 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
248 /* Send the packet down the stack. */
249 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
251 dev->stats.tx_dropped++;
255 /* Update statistics. */
256 dev->stats.tx_packets++;
257 dev->stats.tx_bytes += len;
262 static int chnl_net_open(struct net_device *dev)
264 struct chnl_net *priv = NULL;
266 int llifindex, headroom, tailroom, mtu;
267 struct net_device *lldev;
269 priv = netdev_priv(dev);
271 pr_debug("chnl_net_open: no priv\n");
275 if (priv->state != CAIF_CONNECTING) {
276 priv->state = CAIF_CONNECTING;
277 result = caif_connect_client(dev_net(dev), &priv->conn_req,
278 &priv->chnl, &llifindex,
279 &headroom, &tailroom);
282 "Unable to register and open device,"
288 lldev = __dev_get_by_index(dev_net(dev), llifindex);
291 pr_debug("no interface?\n");
296 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
297 dev->hard_header_len = headroom + lldev->hard_header_len +
298 lldev->needed_tailroom;
301 * MTU, head-room etc is not know before we have a
302 * CAIF link layer device available. MTU calculation may
303 * override initial RTNL configuration.
304 * MTU is minimum of current mtu, link layer mtu pluss
305 * CAIF head and tail, and PDP GPRS contexts max MTU.
307 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
308 mtu = min_t(int, GPRS_PDP_MTU, mtu);
309 dev_set_mtu(dev, mtu);
312 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
318 rtnl_unlock(); /* Release RTNL lock during connect wait */
320 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
321 priv->state != CAIF_CONNECTING,
326 if (result == -ERESTARTSYS) {
327 pr_debug("wait_event_interruptible woken by a signal\n");
328 result = -ERESTARTSYS;
333 pr_debug("connect timeout\n");
334 caif_disconnect_client(dev_net(dev), &priv->chnl);
335 priv->state = CAIF_DISCONNECTED;
336 pr_debug("state disconnected\n");
341 if (priv->state != CAIF_CONNECTED) {
342 pr_debug("connect failed\n");
343 result = -ECONNREFUSED;
346 pr_debug("CAIF Netdevice connected\n");
350 caif_disconnect_client(dev_net(dev), &priv->chnl);
351 priv->state = CAIF_DISCONNECTED;
352 pr_debug("state disconnected\n");
357 static int chnl_net_stop(struct net_device *dev)
359 struct chnl_net *priv;
362 priv = netdev_priv(dev);
363 priv->state = CAIF_DISCONNECTED;
364 caif_disconnect_client(dev_net(dev), &priv->chnl);
368 static int chnl_net_init(struct net_device *dev)
370 struct chnl_net *priv;
372 priv = netdev_priv(dev);
373 strncpy(priv->name, dev->name, sizeof(priv->name));
377 static void chnl_net_uninit(struct net_device *dev)
379 struct chnl_net *priv;
381 priv = netdev_priv(dev);
382 robust_list_del(&priv->list_field);
385 static const struct net_device_ops netdev_ops = {
386 .ndo_open = chnl_net_open,
387 .ndo_stop = chnl_net_stop,
388 .ndo_init = chnl_net_init,
389 .ndo_uninit = chnl_net_uninit,
390 .ndo_start_xmit = chnl_net_start_xmit,
393 static void chnl_net_destructor(struct net_device *dev)
395 struct chnl_net *priv = netdev_priv(dev);
396 caif_free_client(&priv->chnl);
400 static void ipcaif_net_setup(struct net_device *dev)
402 struct chnl_net *priv;
403 dev->netdev_ops = &netdev_ops;
404 dev->destructor = chnl_net_destructor;
405 dev->flags |= IFF_NOARP;
406 dev->flags |= IFF_POINTOPOINT;
407 dev->mtu = GPRS_PDP_MTU;
408 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
410 priv = netdev_priv(dev);
411 priv->chnl.receive = chnl_recv_cb;
412 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
414 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
415 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
416 priv->conn_req.priority = CAIF_PRIO_LOW;
417 /* Insert illegal value */
418 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
419 priv->flowenabled = false;
421 init_waitqueue_head(&priv->netmgmt_wq);
425 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
427 struct chnl_net *priv;
429 priv = netdev_priv(dev);
430 if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
431 priv->conn_req.sockaddr.u.dgm.connection_id) ||
432 nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
433 priv->conn_req.sockaddr.u.dgm.connection_id))
434 goto nla_put_failure;
435 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
436 if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
437 goto nla_put_failure;
444 static void caif_netlink_parms(struct nlattr *data[],
445 struct caif_connect_request *conn_req)
448 pr_warn("no params data found\n");
451 if (data[IFLA_CAIF_IPV4_CONNID])
452 conn_req->sockaddr.u.dgm.connection_id =
453 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
454 if (data[IFLA_CAIF_IPV6_CONNID])
455 conn_req->sockaddr.u.dgm.connection_id =
456 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
457 if (data[IFLA_CAIF_LOOPBACK]) {
458 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
459 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
461 conn_req->protocol = CAIFPROTO_DATAGRAM;
465 static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
466 struct nlattr *tb[], struct nlattr *data[])
469 struct chnl_net *caifdev;
471 caifdev = netdev_priv(dev);
472 caif_netlink_parms(data, &caifdev->conn_req);
473 dev_net_set(caifdev->netdev, src_net);
475 ret = register_netdevice(dev);
477 pr_warn("device rtml registration failed\n");
479 list_add(&caifdev->list_field, &chnl_net_list);
481 /* Use ifindex as connection id, and use loopback channel default. */
482 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
483 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
484 caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
489 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
490 struct nlattr *data[])
492 struct chnl_net *caifdev;
494 caifdev = netdev_priv(dev);
495 caif_netlink_parms(data, &caifdev->conn_req);
496 netdev_state_change(dev);
500 static size_t ipcaif_get_size(const struct net_device *dev)
503 /* IFLA_CAIF_IPV4_CONNID */
505 /* IFLA_CAIF_IPV6_CONNID */
507 /* IFLA_CAIF_LOOPBACK */
512 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
513 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
514 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
515 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
519 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
521 .priv_size = sizeof(struct chnl_net),
522 .setup = ipcaif_net_setup,
523 .maxtype = IFLA_CAIF_MAX,
524 .policy = ipcaif_policy,
525 .newlink = ipcaif_newlink,
526 .changelink = ipcaif_changelink,
527 .get_size = ipcaif_get_size,
528 .fill_info = ipcaif_fill_info,
532 static int __init chnl_init_module(void)
534 return rtnl_link_register(&ipcaif_link_ops);
537 static void __exit chnl_exit_module(void)
539 struct chnl_net *dev = NULL;
540 struct list_head *list_node;
541 struct list_head *_tmp;
542 rtnl_link_unregister(&ipcaif_link_ops);
544 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
545 dev = list_entry(list_node, struct chnl_net, list_field);
552 module_init(chnl_init_module);
553 module_exit(chnl_exit_module);