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 caif_connect_request conn_req;
48 struct list_head list_field;
49 struct net_device *netdev;
51 wait_queue_head_t netmgmt_wq;
52 /* Flow status to remember and control the transmission. */
54 enum caif_states state;
57 static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
60 struct chnl_net *priv;
65 priv = container_of(layr, struct chnl_net, chnl);
69 skb = (struct sk_buff *) cfpkt_tonative(pkt);
71 /* Get length of CAIF packet. */
74 /* Pass some minimum information and
75 * send the packet to the net stack.
77 skb->dev = priv->netdev;
79 /* check the version of IP */
80 ip_version = skb_header_pointer(skb, 0, 1, &buf);
86 switch (*ip_version >> 4) {
88 skb->protocol = htons(ETH_P_IP);
91 skb->protocol = htons(ETH_P_IPV6);
95 priv->netdev->stats.rx_errors++;
99 /* If we change the header in loop mode, the checksum is corrupted. */
100 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
101 skb->ip_summed = CHECKSUM_UNNECESSARY;
103 skb->ip_summed = CHECKSUM_NONE;
110 /* Update statistics. */
111 priv->netdev->stats.rx_packets++;
112 priv->netdev->stats.rx_bytes += pktlen;
117 static int delete_device(struct chnl_net *dev)
121 unregister_netdevice(dev->netdev);
125 static void close_work(struct work_struct *work)
127 struct chnl_net *dev = NULL;
128 struct list_head *list_node;
129 struct list_head *_tmp;
132 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
133 dev = list_entry(list_node, struct chnl_net, list_field);
134 if (dev->state == CAIF_SHUTDOWN)
135 dev_close(dev->netdev);
139 static DECLARE_WORK(close_worker, close_work);
141 static void chnl_hold(struct cflayer *lyr)
143 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
144 dev_hold(priv->netdev);
147 static void chnl_put(struct cflayer *lyr)
149 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
150 dev_put(priv->netdev);
153 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
156 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
157 pr_debug("NET flowctrl func called flow: %s\n",
158 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
159 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
160 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
161 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
162 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
163 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
164 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
169 case CAIF_CTRLCMD_FLOW_OFF_IND:
170 priv->flowenabled = false;
171 netif_stop_queue(priv->netdev);
173 case CAIF_CTRLCMD_DEINIT_RSP:
174 priv->state = CAIF_DISCONNECTED;
176 case CAIF_CTRLCMD_INIT_FAIL_RSP:
177 priv->state = CAIF_DISCONNECTED;
178 wake_up_interruptible(&priv->netmgmt_wq);
180 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
181 priv->state = CAIF_SHUTDOWN;
182 netif_tx_disable(priv->netdev);
183 schedule_work(&close_worker);
185 case CAIF_CTRLCMD_FLOW_ON_IND:
186 priv->flowenabled = true;
187 netif_wake_queue(priv->netdev);
189 case CAIF_CTRLCMD_INIT_RSP:
190 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
191 priv->state = CAIF_CONNECTED;
192 priv->flowenabled = true;
193 netif_wake_queue(priv->netdev);
194 wake_up_interruptible(&priv->netmgmt_wq);
201 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
203 struct chnl_net *priv;
204 struct cfpkt *pkt = NULL;
207 /* Get our private data. */
208 priv = netdev_priv(dev);
210 if (skb->len > priv->netdev->mtu) {
211 pr_warn("Size of skb exceeded MTU\n");
213 dev->stats.tx_errors++;
217 if (!priv->flowenabled) {
218 pr_debug("dropping packets flow off\n");
220 dev->stats.tx_dropped++;
224 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
225 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
227 /* Store original SKB length. */
230 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
232 /* Send the packet down the stack. */
233 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
235 dev->stats.tx_dropped++;
239 /* Update statistics. */
240 dev->stats.tx_packets++;
241 dev->stats.tx_bytes += len;
246 static int chnl_net_open(struct net_device *dev)
248 struct chnl_net *priv = NULL;
250 int llifindex, headroom, tailroom, mtu;
251 struct net_device *lldev;
253 priv = netdev_priv(dev);
255 pr_debug("chnl_net_open: no priv\n");
259 if (priv->state != CAIF_CONNECTING) {
260 priv->state = CAIF_CONNECTING;
261 result = caif_connect_client(dev_net(dev), &priv->conn_req,
262 &priv->chnl, &llifindex,
263 &headroom, &tailroom);
266 "Unable to register and open device,"
272 lldev = __dev_get_by_index(dev_net(dev), llifindex);
275 pr_debug("no interface?\n");
280 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
281 dev->hard_header_len = headroom + lldev->hard_header_len +
282 lldev->needed_tailroom;
285 * MTU, head-room etc is not know before we have a
286 * CAIF link layer device available. MTU calculation may
287 * override initial RTNL configuration.
288 * MTU is minimum of current mtu, link layer mtu pluss
289 * CAIF head and tail, and PDP GPRS contexts max MTU.
291 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
292 mtu = min_t(int, GPRS_PDP_MTU, mtu);
293 dev_set_mtu(dev, mtu);
296 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
302 rtnl_unlock(); /* Release RTNL lock during connect wait */
304 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
305 priv->state != CAIF_CONNECTING,
310 if (result == -ERESTARTSYS) {
311 pr_debug("wait_event_interruptible woken by a signal\n");
312 result = -ERESTARTSYS;
317 pr_debug("connect timeout\n");
318 caif_disconnect_client(dev_net(dev), &priv->chnl);
319 priv->state = CAIF_DISCONNECTED;
320 pr_debug("state disconnected\n");
325 if (priv->state != CAIF_CONNECTED) {
326 pr_debug("connect failed\n");
327 result = -ECONNREFUSED;
330 pr_debug("CAIF Netdevice connected\n");
334 caif_disconnect_client(dev_net(dev), &priv->chnl);
335 priv->state = CAIF_DISCONNECTED;
336 pr_debug("state disconnected\n");
341 static int chnl_net_stop(struct net_device *dev)
343 struct chnl_net *priv;
346 priv = netdev_priv(dev);
347 priv->state = CAIF_DISCONNECTED;
348 caif_disconnect_client(dev_net(dev), &priv->chnl);
352 static int chnl_net_init(struct net_device *dev)
354 struct chnl_net *priv;
356 priv = netdev_priv(dev);
357 strncpy(priv->name, dev->name, sizeof(priv->name));
358 INIT_LIST_HEAD(&priv->list_field);
362 static void chnl_net_uninit(struct net_device *dev)
364 struct chnl_net *priv;
366 priv = netdev_priv(dev);
367 list_del_init(&priv->list_field);
370 static const struct net_device_ops netdev_ops = {
371 .ndo_open = chnl_net_open,
372 .ndo_stop = chnl_net_stop,
373 .ndo_init = chnl_net_init,
374 .ndo_uninit = chnl_net_uninit,
375 .ndo_start_xmit = chnl_net_start_xmit,
378 static void chnl_net_destructor(struct net_device *dev)
380 struct chnl_net *priv = netdev_priv(dev);
381 caif_free_client(&priv->chnl);
384 static void ipcaif_net_setup(struct net_device *dev)
386 struct chnl_net *priv;
387 dev->netdev_ops = &netdev_ops;
388 dev->needs_free_netdev = true;
389 dev->priv_destructor = chnl_net_destructor;
390 dev->flags |= IFF_NOARP;
391 dev->flags |= IFF_POINTOPOINT;
392 dev->mtu = GPRS_PDP_MTU;
393 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
395 priv = netdev_priv(dev);
396 priv->chnl.receive = chnl_recv_cb;
397 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
399 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
400 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
401 priv->conn_req.priority = CAIF_PRIO_LOW;
402 /* Insert illegal value */
403 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
404 priv->flowenabled = false;
406 init_waitqueue_head(&priv->netmgmt_wq);
410 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
412 struct chnl_net *priv;
414 priv = netdev_priv(dev);
415 if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
416 priv->conn_req.sockaddr.u.dgm.connection_id) ||
417 nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
418 priv->conn_req.sockaddr.u.dgm.connection_id))
419 goto nla_put_failure;
420 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
421 if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
422 goto nla_put_failure;
429 static void caif_netlink_parms(struct nlattr *data[],
430 struct caif_connect_request *conn_req)
433 pr_warn("no params data found\n");
436 if (data[IFLA_CAIF_IPV4_CONNID])
437 conn_req->sockaddr.u.dgm.connection_id =
438 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
439 if (data[IFLA_CAIF_IPV6_CONNID])
440 conn_req->sockaddr.u.dgm.connection_id =
441 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
442 if (data[IFLA_CAIF_LOOPBACK]) {
443 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
444 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
446 conn_req->protocol = CAIFPROTO_DATAGRAM;
450 static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
451 struct nlattr *tb[], struct nlattr *data[],
452 struct netlink_ext_ack *extack)
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[],
476 struct netlink_ext_ack *extack)
478 struct chnl_net *caifdev;
480 caifdev = netdev_priv(dev);
481 caif_netlink_parms(data, &caifdev->conn_req);
482 netdev_state_change(dev);
486 static size_t ipcaif_get_size(const struct net_device *dev)
489 /* IFLA_CAIF_IPV4_CONNID */
491 /* IFLA_CAIF_IPV6_CONNID */
493 /* IFLA_CAIF_LOOPBACK */
498 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
499 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
500 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
501 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
505 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
507 .priv_size = sizeof(struct chnl_net),
508 .setup = ipcaif_net_setup,
509 .maxtype = IFLA_CAIF_MAX,
510 .policy = ipcaif_policy,
511 .newlink = ipcaif_newlink,
512 .changelink = ipcaif_changelink,
513 .get_size = ipcaif_get_size,
514 .fill_info = ipcaif_fill_info,
518 static int __init chnl_init_module(void)
520 return rtnl_link_register(&ipcaif_link_ops);
523 static void __exit chnl_exit_module(void)
525 struct chnl_net *dev = NULL;
526 struct list_head *list_node;
527 struct list_head *_tmp;
528 rtnl_link_unregister(&ipcaif_link_ops);
530 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
531 dev = list_entry(list_node, struct chnl_net, list_field);
532 list_del_init(list_node);
538 module_init(chnl_init_module);
539 module_exit(chnl_exit_module);