2 * Copyright (C) ST-Ericsson AB 2010
3 * Authors: Sjur Brendeland/sjur.brandeland@stericsson.com
4 * Daniel Martensson / Daniel.Martensson@stericsson.com
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);
98 switch (*ip_version >> 4) {
100 skb->protocol = htons(ETH_P_IP);
103 skb->protocol = htons(ETH_P_IPV6);
107 priv->netdev->stats.rx_errors++;
111 /* If we change the header in loop mode, the checksum is corrupted. */
112 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
113 skb->ip_summed = CHECKSUM_UNNECESSARY;
115 skb->ip_summed = CHECKSUM_NONE;
122 /* Update statistics. */
123 priv->netdev->stats.rx_packets++;
124 priv->netdev->stats.rx_bytes += pktlen;
129 static int delete_device(struct chnl_net *dev)
133 unregister_netdevice(dev->netdev);
137 static void close_work(struct work_struct *work)
139 struct chnl_net *dev = NULL;
140 struct list_head *list_node;
141 struct list_head *_tmp;
144 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
145 dev = list_entry(list_node, struct chnl_net, list_field);
146 if (dev->state == CAIF_SHUTDOWN)
147 dev_close(dev->netdev);
151 static DECLARE_WORK(close_worker, close_work);
153 static void chnl_hold(struct cflayer *lyr)
155 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
156 dev_hold(priv->netdev);
159 static void chnl_put(struct cflayer *lyr)
161 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
162 dev_put(priv->netdev);
165 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
168 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
169 pr_debug("NET flowctrl func called flow: %s\n",
170 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
171 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
172 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
173 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
174 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
175 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
176 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
181 case CAIF_CTRLCMD_FLOW_OFF_IND:
182 priv->flowenabled = false;
183 netif_stop_queue(priv->netdev);
185 case CAIF_CTRLCMD_DEINIT_RSP:
186 priv->state = CAIF_DISCONNECTED;
188 case CAIF_CTRLCMD_INIT_FAIL_RSP:
189 priv->state = CAIF_DISCONNECTED;
190 wake_up_interruptible(&priv->netmgmt_wq);
192 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
193 priv->state = CAIF_SHUTDOWN;
194 netif_tx_disable(priv->netdev);
195 schedule_work(&close_worker);
197 case CAIF_CTRLCMD_FLOW_ON_IND:
198 priv->flowenabled = true;
199 netif_wake_queue(priv->netdev);
201 case CAIF_CTRLCMD_INIT_RSP:
202 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
203 priv->state = CAIF_CONNECTED;
204 priv->flowenabled = true;
205 netif_wake_queue(priv->netdev);
206 wake_up_interruptible(&priv->netmgmt_wq);
213 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
215 struct chnl_net *priv;
216 struct cfpkt *pkt = NULL;
219 /* Get our private data. */
220 priv = netdev_priv(dev);
222 if (skb->len > priv->netdev->mtu) {
223 pr_warn("Size of skb exceeded MTU\n");
225 dev->stats.tx_errors++;
229 if (!priv->flowenabled) {
230 pr_debug("dropping packets flow off\n");
232 dev->stats.tx_dropped++;
236 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
237 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
239 /* Store original SKB length. */
242 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
244 /* Send the packet down the stack. */
245 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
247 dev->stats.tx_dropped++;
251 /* Update statistics. */
252 dev->stats.tx_packets++;
253 dev->stats.tx_bytes += len;
258 static int chnl_net_open(struct net_device *dev)
260 struct chnl_net *priv = NULL;
262 int llifindex, headroom, tailroom, mtu;
263 struct net_device *lldev;
265 priv = netdev_priv(dev);
267 pr_debug("chnl_net_open: no priv\n");
271 if (priv->state != CAIF_CONNECTING) {
272 priv->state = CAIF_CONNECTING;
273 result = caif_connect_client(dev_net(dev), &priv->conn_req,
274 &priv->chnl, &llifindex,
275 &headroom, &tailroom);
278 "Unable to register and open device,"
284 lldev = dev_get_by_index(dev_net(dev), llifindex);
287 pr_debug("no interface?\n");
292 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
293 dev->hard_header_len = headroom + lldev->hard_header_len +
294 lldev->needed_tailroom;
297 * MTU, head-room etc is not know before we have a
298 * CAIF link layer device available. MTU calculation may
299 * override initial RTNL configuration.
300 * MTU is minimum of current mtu, link layer mtu pluss
301 * CAIF head and tail, and PDP GPRS contexts max MTU.
303 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
304 mtu = min_t(int, GPRS_PDP_MTU, mtu);
305 dev_set_mtu(dev, mtu);
309 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
315 rtnl_unlock(); /* Release RTNL lock during connect wait */
317 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
318 priv->state != CAIF_CONNECTING,
323 if (result == -ERESTARTSYS) {
324 pr_debug("wait_event_interruptible woken by a signal\n");
325 result = -ERESTARTSYS;
330 pr_debug("connect timeout\n");
331 caif_disconnect_client(dev_net(dev), &priv->chnl);
332 priv->state = CAIF_DISCONNECTED;
333 pr_debug("state disconnected\n");
338 if (priv->state != CAIF_CONNECTED) {
339 pr_debug("connect failed\n");
340 result = -ECONNREFUSED;
343 pr_debug("CAIF Netdevice connected\n");
347 caif_disconnect_client(dev_net(dev), &priv->chnl);
348 priv->state = CAIF_DISCONNECTED;
349 pr_debug("state disconnected\n");
354 static int chnl_net_stop(struct net_device *dev)
356 struct chnl_net *priv;
359 priv = netdev_priv(dev);
360 priv->state = CAIF_DISCONNECTED;
361 caif_disconnect_client(dev_net(dev), &priv->chnl);
365 static int chnl_net_init(struct net_device *dev)
367 struct chnl_net *priv;
369 priv = netdev_priv(dev);
370 strncpy(priv->name, dev->name, sizeof(priv->name));
374 static void chnl_net_uninit(struct net_device *dev)
376 struct chnl_net *priv;
378 priv = netdev_priv(dev);
379 robust_list_del(&priv->list_field);
382 static const struct net_device_ops netdev_ops = {
383 .ndo_open = chnl_net_open,
384 .ndo_stop = chnl_net_stop,
385 .ndo_init = chnl_net_init,
386 .ndo_uninit = chnl_net_uninit,
387 .ndo_start_xmit = chnl_net_start_xmit,
390 static void chnl_net_destructor(struct net_device *dev)
392 struct chnl_net *priv = netdev_priv(dev);
393 caif_free_client(&priv->chnl);
397 static void ipcaif_net_setup(struct net_device *dev)
399 struct chnl_net *priv;
400 dev->netdev_ops = &netdev_ops;
401 dev->destructor = chnl_net_destructor;
402 dev->flags |= IFF_NOARP;
403 dev->flags |= IFF_POINTOPOINT;
404 dev->mtu = GPRS_PDP_MTU;
405 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
407 priv = netdev_priv(dev);
408 priv->chnl.receive = chnl_recv_cb;
409 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
411 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
412 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
413 priv->conn_req.priority = CAIF_PRIO_LOW;
414 /* Insert illegal value */
415 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
416 priv->flowenabled = false;
418 init_waitqueue_head(&priv->netmgmt_wq);
422 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
424 struct chnl_net *priv;
426 priv = netdev_priv(dev);
427 if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
428 priv->conn_req.sockaddr.u.dgm.connection_id) ||
429 nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
430 priv->conn_req.sockaddr.u.dgm.connection_id))
431 goto nla_put_failure;
432 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
433 if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
434 goto nla_put_failure;
441 static void caif_netlink_parms(struct nlattr *data[],
442 struct caif_connect_request *conn_req)
445 pr_warn("no params data found\n");
448 if (data[IFLA_CAIF_IPV4_CONNID])
449 conn_req->sockaddr.u.dgm.connection_id =
450 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
451 if (data[IFLA_CAIF_IPV6_CONNID])
452 conn_req->sockaddr.u.dgm.connection_id =
453 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
454 if (data[IFLA_CAIF_LOOPBACK]) {
455 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
456 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
458 conn_req->protocol = CAIFPROTO_DATAGRAM;
462 static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
463 struct nlattr *tb[], struct nlattr *data[])
466 struct chnl_net *caifdev;
468 caifdev = netdev_priv(dev);
469 caif_netlink_parms(data, &caifdev->conn_req);
470 dev_net_set(caifdev->netdev, src_net);
472 ret = register_netdevice(dev);
474 pr_warn("device rtml registration failed\n");
476 list_add(&caifdev->list_field, &chnl_net_list);
478 /* Use ifindex as connection id, and use loopback channel default. */
479 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
480 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
481 caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
486 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
487 struct nlattr *data[])
489 struct chnl_net *caifdev;
491 caifdev = netdev_priv(dev);
492 caif_netlink_parms(data, &caifdev->conn_req);
493 netdev_state_change(dev);
497 static size_t ipcaif_get_size(const struct net_device *dev)
500 /* IFLA_CAIF_IPV4_CONNID */
502 /* IFLA_CAIF_IPV6_CONNID */
504 /* IFLA_CAIF_LOOPBACK */
509 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
510 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
511 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
512 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
516 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
518 .priv_size = sizeof(struct chnl_net),
519 .setup = ipcaif_net_setup,
520 .maxtype = IFLA_CAIF_MAX,
521 .policy = ipcaif_policy,
522 .newlink = ipcaif_newlink,
523 .changelink = ipcaif_changelink,
524 .get_size = ipcaif_get_size,
525 .fill_info = ipcaif_fill_info,
529 static int __init chnl_init_module(void)
531 return rtnl_link_register(&ipcaif_link_ops);
534 static void __exit chnl_exit_module(void)
536 struct chnl_net *dev = NULL;
537 struct list_head *list_node;
538 struct list_head *_tmp;
539 rtnl_link_unregister(&ipcaif_link_ops);
541 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
542 dev = list_entry(list_node, struct chnl_net, list_field);
549 module_init(chnl_init_module);
550 module_exit(chnl_exit_module);