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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) ST-Ericsson AB 2010
  4 * Authors:	Sjur Brendeland
  5 *		Daniel Martensson
  6 */
  7
  8#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
  9
 10#include <linux/fs.h>
 11#include <linux/init.h>
 12#include <linux/module.h>
 13#include <linux/netdevice.h>
 14#include <linux/if_ether.h>
 15#include <linux/ip.h>
 16#include <linux/sched.h>
 17#include <linux/sockios.h>
 18#include <linux/caif/if_caif.h>
 19#include <net/rtnetlink.h>
 20#include <net/caif/caif_layer.h>
 21#include <net/caif/cfpkt.h>
 22#include <net/caif/caif_dev.h>
 23
 24/* GPRS PDP connection has MTU to 1500 */
 25#define GPRS_PDP_MTU 1500
 26/* 5 sec. connect timeout */
 27#define CONNECT_TIMEOUT (5 * HZ)
 28#define CAIF_NET_DEFAULT_QUEUE_LEN 500
 29#define UNDEF_CONNID 0xffffffff
 30
 31/*This list is protected by the rtnl lock. */
 32static LIST_HEAD(chnl_net_list);
 33
 34MODULE_LICENSE("GPL");
 35MODULE_ALIAS_RTNL_LINK("caif");
 36
 37enum caif_states {
 38	CAIF_CONNECTED		= 1,
 39	CAIF_CONNECTING,
 40	CAIF_DISCONNECTED,
 41	CAIF_SHUTDOWN
 42};
 43
 44struct chnl_net {
 45	struct cflayer chnl;
 46	struct caif_connect_request conn_req;
 47	struct list_head list_field;
 48	struct net_device *netdev;
 49	char name[256];
 50	wait_queue_head_t netmgmt_wq;
 51	/* Flow status to remember and control the transmission. */
 52	bool flowenabled;
 53	enum caif_states state;
 54};
 55
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 56static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
 57{
 58	struct sk_buff *skb;
 59	struct chnl_net *priv;
 60	int pktlen;
 61	const u8 *ip_version;
 62	u8 buf;
 63
 64	priv = container_of(layr, struct chnl_net, chnl);
 
 
 65
 66	skb = (struct sk_buff *) cfpkt_tonative(pkt);
 67
 68	/* Get length of CAIF packet. */
 69	pktlen = skb->len;
 70
 71	/* Pass some minimum information and
 72	 * send the packet to the net stack.
 73	 */
 74	skb->dev = priv->netdev;
 75
 76	/* check the version of IP */
 77	ip_version = skb_header_pointer(skb, 0, 1, &buf);
 78	if (!ip_version) {
 79		kfree_skb(skb);
 80		return -EINVAL;
 81	}
 82
 83	switch (*ip_version >> 4) {
 84	case 4:
 85		skb->protocol = htons(ETH_P_IP);
 86		break;
 87	case 6:
 88		skb->protocol = htons(ETH_P_IPV6);
 89		break;
 90	default:
 91		kfree_skb(skb);
 92		priv->netdev->stats.rx_errors++;
 93		return -EINVAL;
 94	}
 95
 96	/* If we change the header in loop mode, the checksum is corrupted. */
 97	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
 98		skb->ip_summed = CHECKSUM_UNNECESSARY;
 99	else
100		skb->ip_summed = CHECKSUM_NONE;
101
102	netif_rx(skb);
 
 
 
103
104	/* Update statistics. */
105	priv->netdev->stats.rx_packets++;
106	priv->netdev->stats.rx_bytes += pktlen;
107
108	return 0;
109}
110
111static int delete_device(struct chnl_net *dev)
112{
113	ASSERT_RTNL();
114	if (dev->netdev)
115		unregister_netdevice(dev->netdev);
116	return 0;
117}
118
119static void close_work(struct work_struct *work)
120{
121	struct chnl_net *dev = NULL;
122	struct list_head *list_node;
123	struct list_head *_tmp;
124
125	rtnl_lock();
126	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
127		dev = list_entry(list_node, struct chnl_net, list_field);
128		if (dev->state == CAIF_SHUTDOWN)
129			dev_close(dev->netdev);
130	}
131	rtnl_unlock();
132}
133static DECLARE_WORK(close_worker, close_work);
134
135static void chnl_hold(struct cflayer *lyr)
136{
137	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
138	dev_hold(priv->netdev);
139}
140
141static void chnl_put(struct cflayer *lyr)
142{
143	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
144	dev_put(priv->netdev);
145}
146
147static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
148			     int phyid)
149{
150	struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
151	pr_debug("NET flowctrl func called flow: %s\n",
152		flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
153		flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
154		flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
155		flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
156		flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
157		flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
158		 "REMOTE_SHUTDOWN" : "UNKNOWN CTRL COMMAND");
159
160
161
162	switch (flow) {
163	case CAIF_CTRLCMD_FLOW_OFF_IND:
164		priv->flowenabled = false;
165		netif_stop_queue(priv->netdev);
166		break;
167	case CAIF_CTRLCMD_DEINIT_RSP:
168		priv->state = CAIF_DISCONNECTED;
169		break;
170	case CAIF_CTRLCMD_INIT_FAIL_RSP:
171		priv->state = CAIF_DISCONNECTED;
172		wake_up_interruptible(&priv->netmgmt_wq);
173		break;
174	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
175		priv->state = CAIF_SHUTDOWN;
176		netif_tx_disable(priv->netdev);
177		schedule_work(&close_worker);
178		break;
179	case CAIF_CTRLCMD_FLOW_ON_IND:
180		priv->flowenabled = true;
181		netif_wake_queue(priv->netdev);
182		break;
183	case CAIF_CTRLCMD_INIT_RSP:
184		caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
185		priv->state = CAIF_CONNECTED;
186		priv->flowenabled = true;
187		netif_wake_queue(priv->netdev);
188		wake_up_interruptible(&priv->netmgmt_wq);
189		break;
190	default:
191		break;
192	}
193}
194
195static netdev_tx_t chnl_net_start_xmit(struct sk_buff *skb,
196				       struct net_device *dev)
197{
198	struct chnl_net *priv;
199	struct cfpkt *pkt = NULL;
200	int len;
201	int result = -1;
202	/* Get our private data. */
203	priv = netdev_priv(dev);
204
205	if (skb->len > priv->netdev->mtu) {
206		pr_warn("Size of skb exceeded MTU\n");
207		kfree_skb(skb);
208		dev->stats.tx_errors++;
209		return NETDEV_TX_OK;
210	}
211
212	if (!priv->flowenabled) {
213		pr_debug("dropping packets flow off\n");
214		kfree_skb(skb);
215		dev->stats.tx_dropped++;
216		return NETDEV_TX_OK;
217	}
218
219	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
220		swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
221
222	/* Store original SKB length. */
223	len = skb->len;
224
225	pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
226
227	/* Send the packet down the stack. */
228	result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
229	if (result) {
230		dev->stats.tx_dropped++;
231		return NETDEV_TX_OK;
232	}
233
234	/* Update statistics. */
235	dev->stats.tx_packets++;
236	dev->stats.tx_bytes += len;
237
238	return NETDEV_TX_OK;
239}
240
241static int chnl_net_open(struct net_device *dev)
242{
243	struct chnl_net *priv = NULL;
244	int result = -1;
245	int llifindex, headroom, tailroom, mtu;
246	struct net_device *lldev;
247	ASSERT_RTNL();
248	priv = netdev_priv(dev);
249	if (!priv) {
250		pr_debug("chnl_net_open: no priv\n");
251		return -ENODEV;
252	}
253
254	if (priv->state != CAIF_CONNECTING) {
255		priv->state = CAIF_CONNECTING;
256		result = caif_connect_client(dev_net(dev), &priv->conn_req,
257						&priv->chnl, &llifindex,
258						&headroom, &tailroom);
259		if (result != 0) {
260				pr_debug("err: "
261					 "Unable to register and open device,"
262					 " Err:%d\n",
263					 result);
264				goto error;
265		}
266
267		lldev = __dev_get_by_index(dev_net(dev), llifindex);
268
269		if (lldev == NULL) {
270			pr_debug("no interface?\n");
271			result = -ENODEV;
272			goto error;
273		}
274
275		dev->needed_tailroom = tailroom + lldev->needed_tailroom;
276		dev->hard_header_len = headroom + lldev->hard_header_len +
277			lldev->needed_tailroom;
278
279		/*
280		 * MTU, head-room etc is not know before we have a
281		 * CAIF link layer device available. MTU calculation may
282		 * override initial RTNL configuration.
283		 * MTU is minimum of current mtu, link layer mtu pluss
284		 * CAIF head and tail, and PDP GPRS contexts max MTU.
285		 */
286		mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
287		mtu = min_t(int, GPRS_PDP_MTU, mtu);
288		dev_set_mtu(dev, mtu);
289
290		if (mtu < 100) {
291			pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
292			result = -ENODEV;
293			goto error;
294		}
295	}
296
297	rtnl_unlock();  /* Release RTNL lock during connect wait */
298
299	result = wait_event_interruptible_timeout(priv->netmgmt_wq,
300						priv->state != CAIF_CONNECTING,
301						CONNECT_TIMEOUT);
302
303	rtnl_lock();
304
305	if (result == -ERESTARTSYS) {
306		pr_debug("wait_event_interruptible woken by a signal\n");
307		result = -ERESTARTSYS;
308		goto error;
309	}
310
311	if (result == 0) {
312		pr_debug("connect timeout\n");
 
 
 
313		result = -ETIMEDOUT;
314		goto error;
315	}
316
317	if (priv->state != CAIF_CONNECTED) {
318		pr_debug("connect failed\n");
319		result = -ECONNREFUSED;
320		goto error;
321	}
322	pr_debug("CAIF Netdevice connected\n");
323	return 0;
324
325error:
326	caif_disconnect_client(dev_net(dev), &priv->chnl);
327	priv->state = CAIF_DISCONNECTED;
328	pr_debug("state disconnected\n");
329	return result;
330
331}
332
333static int chnl_net_stop(struct net_device *dev)
334{
335	struct chnl_net *priv;
336
337	ASSERT_RTNL();
338	priv = netdev_priv(dev);
339	priv->state = CAIF_DISCONNECTED;
340	caif_disconnect_client(dev_net(dev), &priv->chnl);
341	return 0;
342}
343
344static int chnl_net_init(struct net_device *dev)
345{
346	struct chnl_net *priv;
347	ASSERT_RTNL();
348	priv = netdev_priv(dev);
349	strncpy(priv->name, dev->name, sizeof(priv->name));
350	INIT_LIST_HEAD(&priv->list_field);
351	return 0;
352}
353
354static void chnl_net_uninit(struct net_device *dev)
355{
356	struct chnl_net *priv;
357	ASSERT_RTNL();
358	priv = netdev_priv(dev);
359	list_del_init(&priv->list_field);
360}
361
362static const struct net_device_ops netdev_ops = {
363	.ndo_open = chnl_net_open,
364	.ndo_stop = chnl_net_stop,
365	.ndo_init = chnl_net_init,
366	.ndo_uninit = chnl_net_uninit,
367	.ndo_start_xmit = chnl_net_start_xmit,
368};
369
370static void chnl_net_destructor(struct net_device *dev)
371{
372	struct chnl_net *priv = netdev_priv(dev);
373	caif_free_client(&priv->chnl);
374}
375
376static void ipcaif_net_setup(struct net_device *dev)
377{
378	struct chnl_net *priv;
379	dev->netdev_ops = &netdev_ops;
380	dev->needs_free_netdev = true;
381	dev->priv_destructor = chnl_net_destructor;
382	dev->flags |= IFF_NOARP;
383	dev->flags |= IFF_POINTOPOINT;
384	dev->mtu = GPRS_PDP_MTU;
385	dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
386
387	priv = netdev_priv(dev);
388	priv->chnl.receive = chnl_recv_cb;
389	priv->chnl.ctrlcmd = chnl_flowctrl_cb;
390	priv->netdev = dev;
391	priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
392	priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
393	priv->conn_req.priority = CAIF_PRIO_LOW;
394	/* Insert illegal value */
395	priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
396	priv->flowenabled = false;
397
398	init_waitqueue_head(&priv->netmgmt_wq);
399}
400
401
402static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
403{
404	struct chnl_net *priv;
405	u8 loop;
406	priv = netdev_priv(dev);
407	if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
408			priv->conn_req.sockaddr.u.dgm.connection_id) ||
409	    nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
410			priv->conn_req.sockaddr.u.dgm.connection_id))
411		goto nla_put_failure;
412	loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
413	if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
414		goto nla_put_failure;
415	return 0;
416nla_put_failure:
417	return -EMSGSIZE;
418
419}
420
421static void caif_netlink_parms(struct nlattr *data[],
422			       struct caif_connect_request *conn_req)
423{
424	if (!data) {
425		pr_warn("no params data found\n");
426		return;
427	}
428	if (data[IFLA_CAIF_IPV4_CONNID])
429		conn_req->sockaddr.u.dgm.connection_id =
430			nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
431	if (data[IFLA_CAIF_IPV6_CONNID])
432		conn_req->sockaddr.u.dgm.connection_id =
433			nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
434	if (data[IFLA_CAIF_LOOPBACK]) {
435		if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
436			conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
437		else
438			conn_req->protocol = CAIFPROTO_DATAGRAM;
439	}
440}
441
442static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
443			  struct nlattr *tb[], struct nlattr *data[],
444			  struct netlink_ext_ack *extack)
445{
446	int ret;
447	struct chnl_net *caifdev;
448	ASSERT_RTNL();
449	caifdev = netdev_priv(dev);
450	caif_netlink_parms(data, &caifdev->conn_req);
451
452	ret = register_netdevice(dev);
453	if (ret)
454		pr_warn("device rtml registration failed\n");
455	else
456		list_add(&caifdev->list_field, &chnl_net_list);
457
458	/* Use ifindex as connection id, and use loopback channel default. */
459	if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
460		caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
461		caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
462	}
463	return ret;
464}
465
466static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
467			     struct nlattr *data[],
468			     struct netlink_ext_ack *extack)
469{
470	struct chnl_net *caifdev;
471	ASSERT_RTNL();
472	caifdev = netdev_priv(dev);
473	caif_netlink_parms(data, &caifdev->conn_req);
474	netdev_state_change(dev);
475	return 0;
476}
477
478static size_t ipcaif_get_size(const struct net_device *dev)
479{
480	return
481		/* IFLA_CAIF_IPV4_CONNID */
482		nla_total_size(4) +
483		/* IFLA_CAIF_IPV6_CONNID */
484		nla_total_size(4) +
485		/* IFLA_CAIF_LOOPBACK */
486		nla_total_size(2) +
487		0;
488}
489
490static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
491	[IFLA_CAIF_IPV4_CONNID]	      = { .type = NLA_U32 },
492	[IFLA_CAIF_IPV6_CONNID]	      = { .type = NLA_U32 },
493	[IFLA_CAIF_LOOPBACK]	      = { .type = NLA_U8 }
494};
495
496
497static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
498	.kind		= "caif",
499	.priv_size	= sizeof(struct chnl_net),
500	.setup		= ipcaif_net_setup,
501	.maxtype	= IFLA_CAIF_MAX,
502	.policy		= ipcaif_policy,
503	.newlink	= ipcaif_newlink,
504	.changelink	= ipcaif_changelink,
505	.get_size	= ipcaif_get_size,
506	.fill_info	= ipcaif_fill_info,
507
508};
509
510static int __init chnl_init_module(void)
511{
512	return rtnl_link_register(&ipcaif_link_ops);
513}
514
515static void __exit chnl_exit_module(void)
516{
517	struct chnl_net *dev = NULL;
518	struct list_head *list_node;
519	struct list_head *_tmp;
520	rtnl_link_unregister(&ipcaif_link_ops);
521	rtnl_lock();
522	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
523		dev = list_entry(list_node, struct chnl_net, list_field);
524		list_del_init(list_node);
525		delete_device(dev);
526	}
527	rtnl_unlock();
528}
529
530module_init(chnl_init_module);
531module_exit(chnl_exit_module);
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) ST-Ericsson AB 2010
  4 * Authors:	Sjur Brendeland
  5 *		Daniel Martensson
  6 */
  7
  8#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
  9
 10#include <linux/fs.h>
 11#include <linux/init.h>
 12#include <linux/module.h>
 13#include <linux/netdevice.h>
 14#include <linux/if_ether.h>
 15#include <linux/ip.h>
 16#include <linux/sched.h>
 17#include <linux/sockios.h>
 18#include <linux/caif/if_caif.h>
 19#include <net/rtnetlink.h>
 20#include <net/caif/caif_layer.h>
 21#include <net/caif/cfpkt.h>
 22#include <net/caif/caif_dev.h>
 23
 24/* GPRS PDP connection has MTU to 1500 */
 25#define GPRS_PDP_MTU 1500
 26/* 5 sec. connect timeout */
 27#define CONNECT_TIMEOUT (5 * HZ)
 28#define CAIF_NET_DEFAULT_QUEUE_LEN 500
 29#define UNDEF_CONNID 0xffffffff
 30
 31/*This list is protected by the rtnl lock. */
 32static LIST_HEAD(chnl_net_list);
 33
 34MODULE_LICENSE("GPL");
 35MODULE_ALIAS_RTNL_LINK("caif");
 36
 37enum caif_states {
 38	CAIF_CONNECTED		= 1,
 39	CAIF_CONNECTING,
 40	CAIF_DISCONNECTED,
 41	CAIF_SHUTDOWN
 42};
 43
 44struct chnl_net {
 45	struct cflayer chnl;
 46	struct caif_connect_request conn_req;
 47	struct list_head list_field;
 48	struct net_device *netdev;
 49	char name[256];
 50	wait_queue_head_t netmgmt_wq;
 51	/* Flow status to remember and control the transmission. */
 52	bool flowenabled;
 53	enum caif_states state;
 54};
 55
 56static void robust_list_del(struct list_head *delete_node)
 57{
 58	struct list_head *list_node;
 59	struct list_head *n;
 60	ASSERT_RTNL();
 61	list_for_each_safe(list_node, n, &chnl_net_list) {
 62		if (list_node == delete_node) {
 63			list_del(list_node);
 64			return;
 65		}
 66	}
 67	WARN_ON(1);
 68}
 69
 70static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
 71{
 72	struct sk_buff *skb;
 73	struct chnl_net *priv;
 74	int pktlen;
 75	const u8 *ip_version;
 76	u8 buf;
 77
 78	priv = container_of(layr, struct chnl_net, chnl);
 79	if (!priv)
 80		return -EINVAL;
 81
 82	skb = (struct sk_buff *) cfpkt_tonative(pkt);
 83
 84	/* Get length of CAIF packet. */
 85	pktlen = skb->len;
 86
 87	/* Pass some minimum information and
 88	 * send the packet to the net stack.
 89	 */
 90	skb->dev = priv->netdev;
 91
 92	/* check the version of IP */
 93	ip_version = skb_header_pointer(skb, 0, 1, &buf);
 94	if (!ip_version) {
 95		kfree_skb(skb);
 96		return -EINVAL;
 97	}
 98
 99	switch (*ip_version >> 4) {
100	case 4:
101		skb->protocol = htons(ETH_P_IP);
102		break;
103	case 6:
104		skb->protocol = htons(ETH_P_IPV6);
105		break;
106	default:
107		kfree_skb(skb);
108		priv->netdev->stats.rx_errors++;
109		return -EINVAL;
110	}
111
112	/* If we change the header in loop mode, the checksum is corrupted. */
113	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
114		skb->ip_summed = CHECKSUM_UNNECESSARY;
115	else
116		skb->ip_summed = CHECKSUM_NONE;
117
118	if (in_interrupt())
119		netif_rx(skb);
120	else
121		netif_rx_ni(skb);
122
123	/* Update statistics. */
124	priv->netdev->stats.rx_packets++;
125	priv->netdev->stats.rx_bytes += pktlen;
126
127	return 0;
128}
129
130static int delete_device(struct chnl_net *dev)
131{
132	ASSERT_RTNL();
133	if (dev->netdev)
134		unregister_netdevice(dev->netdev);
135	return 0;
136}
137
138static void close_work(struct work_struct *work)
139{
140	struct chnl_net *dev = NULL;
141	struct list_head *list_node;
142	struct list_head *_tmp;
143
144	rtnl_lock();
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);
149	}
150	rtnl_unlock();
151}
152static DECLARE_WORK(close_worker, close_work);
153
154static void chnl_hold(struct cflayer *lyr)
155{
156	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
157	dev_hold(priv->netdev);
158}
159
160static void chnl_put(struct cflayer *lyr)
161{
162	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
163	dev_put(priv->netdev);
164}
165
166static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
167			     int phyid)
168{
169	struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
170	pr_debug("NET flowctrl func called flow: %s\n",
171		flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
172		flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
173		flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
174		flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
175		flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
176		flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
177		 "REMOTE_SHUTDOWN" : "UNKNOWN CTRL COMMAND");
178
179
180
181	switch (flow) {
182	case CAIF_CTRLCMD_FLOW_OFF_IND:
183		priv->flowenabled = false;
184		netif_stop_queue(priv->netdev);
185		break;
186	case CAIF_CTRLCMD_DEINIT_RSP:
187		priv->state = CAIF_DISCONNECTED;
188		break;
189	case CAIF_CTRLCMD_INIT_FAIL_RSP:
190		priv->state = CAIF_DISCONNECTED;
191		wake_up_interruptible(&priv->netmgmt_wq);
192		break;
193	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
194		priv->state = CAIF_SHUTDOWN;
195		netif_tx_disable(priv->netdev);
196		schedule_work(&close_worker);
197		break;
198	case CAIF_CTRLCMD_FLOW_ON_IND:
199		priv->flowenabled = true;
200		netif_wake_queue(priv->netdev);
201		break;
202	case CAIF_CTRLCMD_INIT_RSP:
203		caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
204		priv->state = CAIF_CONNECTED;
205		priv->flowenabled = true;
206		netif_wake_queue(priv->netdev);
207		wake_up_interruptible(&priv->netmgmt_wq);
208		break;
209	default:
210		break;
211	}
212}
213
214static netdev_tx_t chnl_net_start_xmit(struct sk_buff *skb,
215				       struct net_device *dev)
216{
217	struct chnl_net *priv;
218	struct cfpkt *pkt = NULL;
219	int len;
220	int result = -1;
221	/* Get our private data. */
222	priv = netdev_priv(dev);
223
224	if (skb->len > priv->netdev->mtu) {
225		pr_warn("Size of skb exceeded MTU\n");
226		kfree_skb(skb);
227		dev->stats.tx_errors++;
228		return NETDEV_TX_OK;
229	}
230
231	if (!priv->flowenabled) {
232		pr_debug("dropping packets flow off\n");
233		kfree_skb(skb);
234		dev->stats.tx_dropped++;
235		return NETDEV_TX_OK;
236	}
237
238	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
239		swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
240
241	/* Store original SKB length. */
242	len = skb->len;
243
244	pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
245
246	/* Send the packet down the stack. */
247	result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
248	if (result) {
249		dev->stats.tx_dropped++;
250		return NETDEV_TX_OK;
251	}
252
253	/* Update statistics. */
254	dev->stats.tx_packets++;
255	dev->stats.tx_bytes += len;
256
257	return NETDEV_TX_OK;
258}
259
260static int chnl_net_open(struct net_device *dev)
261{
262	struct chnl_net *priv = NULL;
263	int result = -1;
264	int llifindex, headroom, tailroom, mtu;
265	struct net_device *lldev;
266	ASSERT_RTNL();
267	priv = netdev_priv(dev);
268	if (!priv) {
269		pr_debug("chnl_net_open: no priv\n");
270		return -ENODEV;
271	}
272
273	if (priv->state != CAIF_CONNECTING) {
274		priv->state = CAIF_CONNECTING;
275		result = caif_connect_client(dev_net(dev), &priv->conn_req,
276						&priv->chnl, &llifindex,
277						&headroom, &tailroom);
278		if (result != 0) {
279				pr_debug("err: "
280					 "Unable to register and open device,"
281					 " Err:%d\n",
282					 result);
283				goto error;
284		}
285
286		lldev = __dev_get_by_index(dev_net(dev), llifindex);
287
288		if (lldev == NULL) {
289			pr_debug("no interface?\n");
290			result = -ENODEV;
291			goto error;
292		}
293
294		dev->needed_tailroom = tailroom + lldev->needed_tailroom;
295		dev->hard_header_len = headroom + lldev->hard_header_len +
296			lldev->needed_tailroom;
297
298		/*
299		 * MTU, head-room etc is not know before we have a
300		 * CAIF link layer device available. MTU calculation may
301		 * override initial RTNL configuration.
302		 * MTU is minimum of current mtu, link layer mtu pluss
303		 * CAIF head and tail, and PDP GPRS contexts max MTU.
304		 */
305		mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
306		mtu = min_t(int, GPRS_PDP_MTU, mtu);
307		dev_set_mtu(dev, mtu);
308
309		if (mtu < 100) {
310			pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
311			result = -ENODEV;
312			goto error;
313		}
314	}
315
316	rtnl_unlock();  /* Release RTNL lock during connect wait */
317
318	result = wait_event_interruptible_timeout(priv->netmgmt_wq,
319						priv->state != CAIF_CONNECTING,
320						CONNECT_TIMEOUT);
321
322	rtnl_lock();
323
324	if (result == -ERESTARTSYS) {
325		pr_debug("wait_event_interruptible woken by a signal\n");
326		result = -ERESTARTSYS;
327		goto error;
328	}
329
330	if (result == 0) {
331		pr_debug("connect timeout\n");
332		caif_disconnect_client(dev_net(dev), &priv->chnl);
333		priv->state = CAIF_DISCONNECTED;
334		pr_debug("state disconnected\n");
335		result = -ETIMEDOUT;
336		goto error;
337	}
338
339	if (priv->state != CAIF_CONNECTED) {
340		pr_debug("connect failed\n");
341		result = -ECONNREFUSED;
342		goto error;
343	}
344	pr_debug("CAIF Netdevice connected\n");
345	return 0;
346
347error:
348	caif_disconnect_client(dev_net(dev), &priv->chnl);
349	priv->state = CAIF_DISCONNECTED;
350	pr_debug("state disconnected\n");
351	return result;
352
353}
354
355static int chnl_net_stop(struct net_device *dev)
356{
357	struct chnl_net *priv;
358
359	ASSERT_RTNL();
360	priv = netdev_priv(dev);
361	priv->state = CAIF_DISCONNECTED;
362	caif_disconnect_client(dev_net(dev), &priv->chnl);
363	return 0;
364}
365
366static int chnl_net_init(struct net_device *dev)
367{
368	struct chnl_net *priv;
369	ASSERT_RTNL();
370	priv = netdev_priv(dev);
371	strncpy(priv->name, dev->name, sizeof(priv->name));
 
372	return 0;
373}
374
375static void chnl_net_uninit(struct net_device *dev)
376{
377	struct chnl_net *priv;
378	ASSERT_RTNL();
379	priv = netdev_priv(dev);
380	robust_list_del(&priv->list_field);
381}
382
383static const struct net_device_ops netdev_ops = {
384	.ndo_open = chnl_net_open,
385	.ndo_stop = chnl_net_stop,
386	.ndo_init = chnl_net_init,
387	.ndo_uninit = chnl_net_uninit,
388	.ndo_start_xmit = chnl_net_start_xmit,
389};
390
391static void chnl_net_destructor(struct net_device *dev)
392{
393	struct chnl_net *priv = netdev_priv(dev);
394	caif_free_client(&priv->chnl);
395}
396
397static void ipcaif_net_setup(struct net_device *dev)
398{
399	struct chnl_net *priv;
400	dev->netdev_ops = &netdev_ops;
401	dev->needs_free_netdev = true;
402	dev->priv_destructor = chnl_net_destructor;
403	dev->flags |= IFF_NOARP;
404	dev->flags |= IFF_POINTOPOINT;
405	dev->mtu = GPRS_PDP_MTU;
406	dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
407
408	priv = netdev_priv(dev);
409	priv->chnl.receive = chnl_recv_cb;
410	priv->chnl.ctrlcmd = chnl_flowctrl_cb;
411	priv->netdev = dev;
412	priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
413	priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
414	priv->conn_req.priority = CAIF_PRIO_LOW;
415	/* Insert illegal value */
416	priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
417	priv->flowenabled = false;
418
419	init_waitqueue_head(&priv->netmgmt_wq);
420}
421
422
423static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
424{
425	struct chnl_net *priv;
426	u8 loop;
427	priv = netdev_priv(dev);
428	if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
429			priv->conn_req.sockaddr.u.dgm.connection_id) ||
430	    nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
431			priv->conn_req.sockaddr.u.dgm.connection_id))
432		goto nla_put_failure;
433	loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
434	if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
435		goto nla_put_failure;
436	return 0;
437nla_put_failure:
438	return -EMSGSIZE;
439
440}
441
442static void caif_netlink_parms(struct nlattr *data[],
443			       struct caif_connect_request *conn_req)
444{
445	if (!data) {
446		pr_warn("no params data found\n");
447		return;
448	}
449	if (data[IFLA_CAIF_IPV4_CONNID])
450		conn_req->sockaddr.u.dgm.connection_id =
451			nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
452	if (data[IFLA_CAIF_IPV6_CONNID])
453		conn_req->sockaddr.u.dgm.connection_id =
454			nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
455	if (data[IFLA_CAIF_LOOPBACK]) {
456		if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
457			conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
458		else
459			conn_req->protocol = CAIFPROTO_DATAGRAM;
460	}
461}
462
463static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
464			  struct nlattr *tb[], struct nlattr *data[],
465			  struct netlink_ext_ack *extack)
466{
467	int ret;
468	struct chnl_net *caifdev;
469	ASSERT_RTNL();
470	caifdev = netdev_priv(dev);
471	caif_netlink_parms(data, &caifdev->conn_req);
472
473	ret = register_netdevice(dev);
474	if (ret)
475		pr_warn("device rtml registration failed\n");
476	else
477		list_add(&caifdev->list_field, &chnl_net_list);
478
479	/* Use ifindex as connection id, and use loopback channel default. */
480	if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
481		caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
482		caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
483	}
484	return ret;
485}
486
487static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
488			     struct nlattr *data[],
489			     struct netlink_ext_ack *extack)
490{
491	struct chnl_net *caifdev;
492	ASSERT_RTNL();
493	caifdev = netdev_priv(dev);
494	caif_netlink_parms(data, &caifdev->conn_req);
495	netdev_state_change(dev);
496	return 0;
497}
498
499static size_t ipcaif_get_size(const struct net_device *dev)
500{
501	return
502		/* IFLA_CAIF_IPV4_CONNID */
503		nla_total_size(4) +
504		/* IFLA_CAIF_IPV6_CONNID */
505		nla_total_size(4) +
506		/* IFLA_CAIF_LOOPBACK */
507		nla_total_size(2) +
508		0;
509}
510
511static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
512	[IFLA_CAIF_IPV4_CONNID]	      = { .type = NLA_U32 },
513	[IFLA_CAIF_IPV6_CONNID]	      = { .type = NLA_U32 },
514	[IFLA_CAIF_LOOPBACK]	      = { .type = NLA_U8 }
515};
516
517
518static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
519	.kind		= "caif",
520	.priv_size	= sizeof(struct chnl_net),
521	.setup		= ipcaif_net_setup,
522	.maxtype	= IFLA_CAIF_MAX,
523	.policy		= ipcaif_policy,
524	.newlink	= ipcaif_newlink,
525	.changelink	= ipcaif_changelink,
526	.get_size	= ipcaif_get_size,
527	.fill_info	= ipcaif_fill_info,
528
529};
530
531static int __init chnl_init_module(void)
532{
533	return rtnl_link_register(&ipcaif_link_ops);
534}
535
536static void __exit chnl_exit_module(void)
537{
538	struct chnl_net *dev = NULL;
539	struct list_head *list_node;
540	struct list_head *_tmp;
541	rtnl_link_unregister(&ipcaif_link_ops);
542	rtnl_lock();
543	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
544		dev = list_entry(list_node, struct chnl_net, list_field);
545		list_del(list_node);
546		delete_device(dev);
547	}
548	rtnl_unlock();
549}
550
551module_init(chnl_init_module);
552module_exit(chnl_exit_module);