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 /* Get length of CAIF packet. */
87 pktlen = cfpkt_getlen(pkt);
89 skb = (struct sk_buff *) cfpkt_tonative(pkt);
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);
99 switch (*ip_version >> 4) {
101 skb->protocol = htons(ETH_P_IP);
104 skb->protocol = htons(ETH_P_IPV6);
110 /* If we change the header in loop mode, the checksum is corrupted. */
111 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
112 skb->ip_summed = CHECKSUM_UNNECESSARY;
114 skb->ip_summed = CHECKSUM_NONE;
121 /* Update statistics. */
122 priv->netdev->stats.rx_packets++;
123 priv->netdev->stats.rx_bytes += pktlen;
128 static int delete_device(struct chnl_net *dev)
132 unregister_netdevice(dev->netdev);
136 static void close_work(struct work_struct *work)
138 struct chnl_net *dev = NULL;
139 struct list_head *list_node;
140 struct list_head *_tmp;
141 /* May be called with or without RTNL lock held */
142 int islocked = rtnl_is_locked();
145 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
146 dev = list_entry(list_node, struct chnl_net, list_field);
147 if (dev->state == CAIF_SHUTDOWN)
148 dev_close(dev->netdev);
153 static DECLARE_WORK(close_worker, close_work);
155 static void chnl_hold(struct cflayer *lyr)
157 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
158 dev_hold(priv->netdev);
161 static void chnl_put(struct cflayer *lyr)
163 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
164 dev_put(priv->netdev);
167 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
170 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
171 pr_debug("NET flowctrl func called flow: %s\n",
172 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
173 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
174 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
175 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
176 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
177 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
178 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
183 case CAIF_CTRLCMD_FLOW_OFF_IND:
184 priv->flowenabled = false;
185 netif_stop_queue(priv->netdev);
187 case CAIF_CTRLCMD_DEINIT_RSP:
188 priv->state = CAIF_DISCONNECTED;
190 case CAIF_CTRLCMD_INIT_FAIL_RSP:
191 priv->state = CAIF_DISCONNECTED;
192 wake_up_interruptible(&priv->netmgmt_wq);
194 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
195 priv->state = CAIF_SHUTDOWN;
196 netif_tx_disable(priv->netdev);
197 schedule_work(&close_worker);
199 case CAIF_CTRLCMD_FLOW_ON_IND:
200 priv->flowenabled = true;
201 netif_wake_queue(priv->netdev);
203 case CAIF_CTRLCMD_INIT_RSP:
204 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
205 priv->state = CAIF_CONNECTED;
206 priv->flowenabled = true;
207 netif_wake_queue(priv->netdev);
208 wake_up_interruptible(&priv->netmgmt_wq);
215 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
217 struct chnl_net *priv;
218 struct cfpkt *pkt = NULL;
221 /* Get our private data. */
222 priv = netdev_priv(dev);
224 if (skb->len > priv->netdev->mtu) {
225 pr_warn("Size of skb exceeded MTU\n");
229 if (!priv->flowenabled) {
230 pr_debug("dropping packets flow off\n");
231 return NETDEV_TX_BUSY;
234 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
235 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
237 /* Store original SKB length. */
240 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
242 /* Send the packet down the stack. */
243 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
245 if (result == -EAGAIN)
246 result = NETDEV_TX_BUSY;
250 /* Update statistics. */
251 dev->stats.tx_packets++;
252 dev->stats.tx_bytes += len;
257 static int chnl_net_open(struct net_device *dev)
259 struct chnl_net *priv = NULL;
261 int llifindex, headroom, tailroom, mtu;
262 struct net_device *lldev;
264 priv = netdev_priv(dev);
266 pr_debug("chnl_net_open: no priv\n");
270 if (priv->state != CAIF_CONNECTING) {
271 priv->state = CAIF_CONNECTING;
272 result = caif_connect_client(dev_net(dev), &priv->conn_req,
273 &priv->chnl, &llifindex,
274 &headroom, &tailroom);
277 "Unable to register and open device,"
283 lldev = dev_get_by_index(dev_net(dev), llifindex);
286 pr_debug("no interface?\n");
291 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
292 dev->hard_header_len = headroom + lldev->hard_header_len +
293 lldev->needed_tailroom;
296 * MTU, head-room etc is not know before we have a
297 * CAIF link layer device available. MTU calculation may
298 * override initial RTNL configuration.
299 * MTU is minimum of current mtu, link layer mtu pluss
300 * CAIF head and tail, and PDP GPRS contexts max MTU.
302 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
303 mtu = min_t(int, GPRS_PDP_MTU, mtu);
304 dev_set_mtu(dev, mtu);
308 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
314 rtnl_unlock(); /* Release RTNL lock during connect wait */
316 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
317 priv->state != CAIF_CONNECTING,
322 if (result == -ERESTARTSYS) {
323 pr_debug("wait_event_interruptible woken by a signal\n");
324 result = -ERESTARTSYS;
329 pr_debug("connect timeout\n");
330 caif_disconnect_client(dev_net(dev), &priv->chnl);
331 priv->state = CAIF_DISCONNECTED;
332 pr_debug("state disconnected\n");
337 if (priv->state != CAIF_CONNECTED) {
338 pr_debug("connect failed\n");
339 result = -ECONNREFUSED;
342 pr_debug("CAIF Netdevice connected\n");
346 caif_disconnect_client(dev_net(dev), &priv->chnl);
347 priv->state = CAIF_DISCONNECTED;
348 pr_debug("state disconnected\n");
353 static int chnl_net_stop(struct net_device *dev)
355 struct chnl_net *priv;
358 priv = netdev_priv(dev);
359 priv->state = CAIF_DISCONNECTED;
360 caif_disconnect_client(dev_net(dev), &priv->chnl);
364 static int chnl_net_init(struct net_device *dev)
366 struct chnl_net *priv;
368 priv = netdev_priv(dev);
369 strncpy(priv->name, dev->name, sizeof(priv->name));
373 static void chnl_net_uninit(struct net_device *dev)
375 struct chnl_net *priv;
377 priv = netdev_priv(dev);
378 robust_list_del(&priv->list_field);
381 static const struct net_device_ops netdev_ops = {
382 .ndo_open = chnl_net_open,
383 .ndo_stop = chnl_net_stop,
384 .ndo_init = chnl_net_init,
385 .ndo_uninit = chnl_net_uninit,
386 .ndo_start_xmit = chnl_net_start_xmit,
389 static void chnl_net_destructor(struct net_device *dev)
391 struct chnl_net *priv = netdev_priv(dev);
392 caif_free_client(&priv->chnl);
396 static void ipcaif_net_setup(struct net_device *dev)
398 struct chnl_net *priv;
399 dev->netdev_ops = &netdev_ops;
400 dev->destructor = chnl_net_destructor;
401 dev->flags |= IFF_NOARP;
402 dev->flags |= IFF_POINTOPOINT;
403 dev->mtu = GPRS_PDP_MTU;
404 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
406 priv = netdev_priv(dev);
407 priv->chnl.receive = chnl_recv_cb;
408 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
410 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
411 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
412 priv->conn_req.priority = CAIF_PRIO_LOW;
413 /* Insert illegal value */
414 priv->conn_req.sockaddr.u.dgm.connection_id = 0;
415 priv->flowenabled = false;
417 init_waitqueue_head(&priv->netmgmt_wq);
421 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
423 struct chnl_net *priv;
425 priv = netdev_priv(dev);
426 NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID,
427 priv->conn_req.sockaddr.u.dgm.connection_id);
428 NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID,
429 priv->conn_req.sockaddr.u.dgm.connection_id);
430 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
431 NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);
440 static void caif_netlink_parms(struct nlattr *data[],
441 struct caif_connect_request *conn_req)
444 pr_warn("no params data found\n");
447 if (data[IFLA_CAIF_IPV4_CONNID])
448 conn_req->sockaddr.u.dgm.connection_id =
449 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
450 if (data[IFLA_CAIF_IPV6_CONNID])
451 conn_req->sockaddr.u.dgm.connection_id =
452 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
453 if (data[IFLA_CAIF_LOOPBACK]) {
454 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
455 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
457 conn_req->protocol = CAIFPROTO_DATAGRAM;
461 static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
462 struct nlattr *tb[], struct nlattr *data[])
465 struct chnl_net *caifdev;
467 caifdev = netdev_priv(dev);
468 caif_netlink_parms(data, &caifdev->conn_req);
469 dev_net_set(caifdev->netdev, src_net);
471 ret = register_netdevice(dev);
473 pr_warn("device rtml registration failed\n");
475 list_add(&caifdev->list_field, &chnl_net_list);
477 /* Take ifindex as connection-id if null */
478 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == 0)
479 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
483 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
484 struct nlattr *data[])
486 struct chnl_net *caifdev;
488 caifdev = netdev_priv(dev);
489 caif_netlink_parms(data, &caifdev->conn_req);
490 netdev_state_change(dev);
494 static size_t ipcaif_get_size(const struct net_device *dev)
497 /* IFLA_CAIF_IPV4_CONNID */
499 /* IFLA_CAIF_IPV6_CONNID */
501 /* IFLA_CAIF_LOOPBACK */
506 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
507 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
508 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
509 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
513 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
515 .priv_size = sizeof(struct chnl_net),
516 .setup = ipcaif_net_setup,
517 .maxtype = IFLA_CAIF_MAX,
518 .policy = ipcaif_policy,
519 .newlink = ipcaif_newlink,
520 .changelink = ipcaif_changelink,
521 .get_size = ipcaif_get_size,
522 .fill_info = ipcaif_fill_info,
526 static int __init chnl_init_module(void)
528 return rtnl_link_register(&ipcaif_link_ops);
531 static void __exit chnl_exit_module(void)
533 struct chnl_net *dev = NULL;
534 struct list_head *list_node;
535 struct list_head *_tmp;
536 rtnl_link_unregister(&ipcaif_link_ops);
538 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
539 dev = list_entry(list_node, struct chnl_net, list_field);
546 module_init(chnl_init_module);
547 module_exit(chnl_exit_module);