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__
10 #include <linux/version.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
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 void robust_list_del(struct list_head *delete_node)
60 struct list_head *list_node;
63 list_for_each_safe(list_node, n, &chnl_net_list) {
64 if (list_node == delete_node) {
72 static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
75 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
81 priv = container_of(layr, struct chnl_net, chnl);
86 skb = (struct sk_buff *) cfpkt_tonative(pkt);
88 /* Get length of CAIF packet. */
91 /* Pass some minimum information and
92 * send the packet to the net stack.
94 skb->dev = priv->netdev;
96 /* check the version of IP */
97 ip_version = skb_header_pointer(skb, 0, 1, &buf);
100 switch (*ip_version >> 4) {
102 skb->protocol = htons(ETH_P_IP);
105 skb->protocol = htons(ETH_P_IPV6);
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;
142 /* May be called with or without RTNL lock held */
143 int islocked = rtnl_is_locked();
146 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
147 dev = list_entry(list_node, struct chnl_net, list_field);
148 if (dev->state == CAIF_SHUTDOWN)
149 dev_close(dev->netdev);
154 static DECLARE_WORK(close_worker, close_work);
156 static void chnl_hold(struct cflayer *lyr)
158 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
159 dev_hold(priv->netdev);
162 static void chnl_put(struct cflayer *lyr)
164 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
165 dev_put(priv->netdev);
168 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
171 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
172 pr_debug("NET flowctrl func called flow: %s\n",
173 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
174 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
175 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
176 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
177 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
178 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
179 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
184 case CAIF_CTRLCMD_FLOW_OFF_IND:
185 priv->flowenabled = false;
186 netif_stop_queue(priv->netdev);
188 case CAIF_CTRLCMD_DEINIT_RSP:
189 priv->state = CAIF_DISCONNECTED;
191 case CAIF_CTRLCMD_INIT_FAIL_RSP:
192 priv->state = CAIF_DISCONNECTED;
193 wake_up_interruptible(&priv->netmgmt_wq);
195 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
196 priv->state = CAIF_SHUTDOWN;
197 netif_tx_disable(priv->netdev);
198 schedule_work(&close_worker);
200 case CAIF_CTRLCMD_FLOW_ON_IND:
201 priv->flowenabled = true;
202 netif_wake_queue(priv->netdev);
204 case CAIF_CTRLCMD_INIT_RSP:
205 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
206 priv->state = CAIF_CONNECTED;
207 priv->flowenabled = true;
208 netif_wake_queue(priv->netdev);
209 wake_up_interruptible(&priv->netmgmt_wq);
216 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
218 struct chnl_net *priv;
219 struct cfpkt *pkt = NULL;
222 /* Get our private data. */
223 priv = netdev_priv(dev);
225 if (skb->len > priv->netdev->mtu) {
226 pr_warn("Size of skb exceeded MTU\n");
230 if (!priv->flowenabled) {
231 pr_debug("dropping packets flow off\n");
232 return NETDEV_TX_BUSY;
235 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
236 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
238 /* Store original SKB length. */
241 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
243 /* Send the packet down the stack. */
244 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
246 if (result == -EAGAIN)
247 result = NETDEV_TX_BUSY;
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 = 0;
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 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 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
432 NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);
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 /* Take ifindex as connection-id if null */
479 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == 0)
480 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
484 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
485 struct nlattr *data[])
487 struct chnl_net *caifdev;
489 caifdev = netdev_priv(dev);
490 caif_netlink_parms(data, &caifdev->conn_req);
491 netdev_state_change(dev);
495 static size_t ipcaif_get_size(const struct net_device *dev)
498 /* IFLA_CAIF_IPV4_CONNID */
500 /* IFLA_CAIF_IPV6_CONNID */
502 /* IFLA_CAIF_LOOPBACK */
507 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
508 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
509 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
510 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
514 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
516 .priv_size = sizeof(struct chnl_net),
517 .setup = ipcaif_net_setup,
518 .maxtype = IFLA_CAIF_MAX,
519 .policy = ipcaif_policy,
520 .newlink = ipcaif_newlink,
521 .changelink = ipcaif_changelink,
522 .get_size = ipcaif_get_size,
523 .fill_info = ipcaif_fill_info,
527 static int __init chnl_init_module(void)
529 return rtnl_link_register(&ipcaif_link_ops);
532 static void __exit chnl_exit_module(void)
534 struct chnl_net *dev = NULL;
535 struct list_head *list_node;
536 struct list_head *_tmp;
537 rtnl_link_unregister(&ipcaif_link_ops);
539 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
540 dev = list_entry(list_node, struct chnl_net, list_field);
547 module_init(chnl_init_module);
548 module_exit(chnl_exit_module);