caif: Bugfixes in CAIF netdevice for close and flow control
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / caif / chnl_net.c
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1/*
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
6 */
7
8#include <linux/version.h>
9#include <linux/fs.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/netdevice.h>
13#include <linux/if_ether.h>
14#include <linux/moduleparam.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/cfcnfg.h>
22#include <net/caif/cfpkt.h>
23#include <net/caif/caif_dev.h>
24
8391c4aa 25/* GPRS PDP connection has MTU to 1500 */
cc36a070 26#define SIZE_MTU 1500
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27/* 5 sec. connect timeout */
28#define CONNECT_TIMEOUT (5 * HZ)
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29#define CAIF_NET_DEFAULT_QUEUE_LEN 500
30
31#undef pr_debug
32#define pr_debug pr_warning
33
34/*This list is protected by the rtnl lock. */
35static LIST_HEAD(chnl_net_list);
36
37MODULE_LICENSE("GPL");
38MODULE_ALIAS_RTNL_LINK("caif");
39
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40enum caif_states {
41 CAIF_CONNECTED = 1,
42 CAIF_CONNECTING,
43 CAIF_DISCONNECTED,
44 CAIF_SHUTDOWN
45};
46
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47struct chnl_net {
48 struct cflayer chnl;
49 struct net_device_stats stats;
50 struct caif_connect_request conn_req;
51 struct list_head list_field;
52 struct net_device *netdev;
53 char name[256];
54 wait_queue_head_t netmgmt_wq;
55 /* Flow status to remember and control the transmission. */
56 bool flowenabled;
8391c4aa 57 enum caif_states state;
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58};
59
60static void robust_list_del(struct list_head *delete_node)
61{
62 struct list_head *list_node;
63 struct list_head *n;
64 ASSERT_RTNL();
65 list_for_each_safe(list_node, n, &chnl_net_list) {
66 if (list_node == delete_node) {
67 list_del(list_node);
8391c4aa 68 return;
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69 }
70 }
8391c4aa 71 WARN_ON(1);
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72}
73
74static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
75{
76 struct sk_buff *skb;
8391c4aa 77 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
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78 int pktlen;
79 int err = 0;
80
81 priv = container_of(layr, struct chnl_net, chnl);
82
83 if (!priv)
84 return -EINVAL;
85
86 /* Get length of CAIF packet. */
87 pktlen = cfpkt_getlen(pkt);
88
89 skb = (struct sk_buff *) cfpkt_tonative(pkt);
90 /* Pass some minimum information and
91 * send the packet to the net stack.
92 */
93 skb->dev = priv->netdev;
94 skb->protocol = htons(ETH_P_IP);
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
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102 if (in_interrupt())
103 netif_rx(skb);
104 else
105 netif_rx_ni(skb);
106
107 /* Update statistics. */
108 priv->netdev->stats.rx_packets++;
109 priv->netdev->stats.rx_bytes += pktlen;
110
111 return err;
112}
113
114static int delete_device(struct chnl_net *dev)
115{
116 ASSERT_RTNL();
117 if (dev->netdev)
118 unregister_netdevice(dev->netdev);
119 return 0;
120}
121
122static void close_work(struct work_struct *work)
123{
124 struct chnl_net *dev = NULL;
125 struct list_head *list_node;
126 struct list_head *_tmp;
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127 /* May be called with or without RTNL lock held */
128 int islocked = rtnl_is_locked();
129 if (!islocked)
130 rtnl_lock();
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131 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
132 dev = list_entry(list_node, struct chnl_net, list_field);
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133 if (dev->state == CAIF_SHUTDOWN)
134 dev_close(dev->netdev);
cc36a070 135 }
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136 if (!islocked)
137 rtnl_unlock();
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138}
139static DECLARE_WORK(close_worker, close_work);
140
141static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
142 int phyid)
143{
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144 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
145 pr_debug("CAIF: %s(): NET flowctrl func called flow: %s\n",
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146 __func__,
147 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
148 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
149 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
150 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
151 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
152 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
153 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
154
8391c4aa 155
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156
157 switch (flow) {
158 case CAIF_CTRLCMD_FLOW_OFF_IND:
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159 priv->flowenabled = false;
160 netif_stop_queue(priv->netdev);
161 break;
cc36a070 162 case CAIF_CTRLCMD_DEINIT_RSP:
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163 priv->state = CAIF_DISCONNECTED;
164 break;
cc36a070 165 case CAIF_CTRLCMD_INIT_FAIL_RSP:
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166 priv->state = CAIF_DISCONNECTED;
167 wake_up_interruptible(&priv->netmgmt_wq);
168 break;
cc36a070 169 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
8391c4aa 170 priv->state = CAIF_SHUTDOWN;
cc36a070 171 netif_tx_disable(priv->netdev);
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172 schedule_work(&close_worker);
173 break;
174 case CAIF_CTRLCMD_FLOW_ON_IND:
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175 priv->flowenabled = true;
176 netif_wake_queue(priv->netdev);
177 break;
cc36a070 178 case CAIF_CTRLCMD_INIT_RSP:
8391c4aa 179 priv->state = CAIF_CONNECTED;
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180 priv->flowenabled = true;
181 netif_wake_queue(priv->netdev);
182 wake_up_interruptible(&priv->netmgmt_wq);
183 break;
184 default:
185 break;
186 }
187}
188
189static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
190{
191 struct chnl_net *priv;
192 struct cfpkt *pkt = NULL;
193 int len;
194 int result = -1;
195 /* Get our private data. */
196 priv = netdev_priv(dev);
197
198 if (skb->len > priv->netdev->mtu) {
199 pr_warning("CAIF: %s(): Size of skb exceeded MTU\n", __func__);
200 return -ENOSPC;
201 }
202
203 if (!priv->flowenabled) {
204 pr_debug("CAIF: %s(): dropping packets flow off\n", __func__);
205 return NETDEV_TX_BUSY;
206 }
207
208 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
209 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
210
211 /* Store original SKB length. */
212 len = skb->len;
213
214 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
215
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216 /* Send the packet down the stack. */
217 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
218 if (result) {
219 if (result == -EAGAIN)
220 result = NETDEV_TX_BUSY;
221 return result;
222 }
223
224 /* Update statistics. */
225 dev->stats.tx_packets++;
226 dev->stats.tx_bytes += len;
227
228 return NETDEV_TX_OK;
229}
230
231static int chnl_net_open(struct net_device *dev)
232{
233 struct chnl_net *priv = NULL;
234 int result = -1;
235 ASSERT_RTNL();
cc36a070 236 priv = netdev_priv(dev);
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237 if (!priv) {
238 pr_debug("CAIF: %s(): chnl_net_open: no priv\n", __func__);
239 return -ENODEV;
240 }
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241
242 if (priv->state != CAIF_CONNECTING) {
243 priv->state = CAIF_CONNECTING;
244 result = caif_connect_client(&priv->conn_req, &priv->chnl);
245 if (result != 0) {
246 priv->state = CAIF_DISCONNECTED;
247 pr_debug("CAIF: %s(): err: "
248 "Unable to register and open device,"
249 " Err:%d\n",
250 __func__,
251 result);
252 return result;
253 }
cc36a070 254 }
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255
256 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
257 priv->state != CAIF_CONNECTING,
258 CONNECT_TIMEOUT);
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259
260 if (result == -ERESTARTSYS) {
261 pr_debug("CAIF: %s(): wait_event_interruptible"
262 " woken by a signal\n", __func__);
263 return -ERESTARTSYS;
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264 }
265 if (result == 0) {
266 pr_debug("CAIF: %s(): connect timeout\n", __func__);
267 caif_disconnect_client(&priv->chnl);
268 priv->state = CAIF_DISCONNECTED;
269 pr_debug("CAIF: %s(): state disconnected\n", __func__);
270 return -ETIMEDOUT;
271 }
cc36a070 272
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273 if (priv->state != CAIF_CONNECTED) {
274 pr_debug("CAIF: %s(): connect failed\n", __func__);
275 return -ECONNREFUSED;
276 }
277 pr_debug("CAIF: %s(): CAIF Netdevice connected\n", __func__);
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278 return 0;
279}
280
281static int chnl_net_stop(struct net_device *dev)
282{
283 struct chnl_net *priv;
8391c4aa 284
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285 ASSERT_RTNL();
286 priv = netdev_priv(dev);
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287 priv->state = CAIF_DISCONNECTED;
288 caif_disconnect_client(&priv->chnl);
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289 return 0;
290}
291
292static int chnl_net_init(struct net_device *dev)
293{
294 struct chnl_net *priv;
295 ASSERT_RTNL();
296 priv = netdev_priv(dev);
297 strncpy(priv->name, dev->name, sizeof(priv->name));
298 return 0;
299}
300
301static void chnl_net_uninit(struct net_device *dev)
302{
303 struct chnl_net *priv;
304 ASSERT_RTNL();
305 priv = netdev_priv(dev);
306 robust_list_del(&priv->list_field);
307}
308
309static const struct net_device_ops netdev_ops = {
310 .ndo_open = chnl_net_open,
311 .ndo_stop = chnl_net_stop,
312 .ndo_init = chnl_net_init,
313 .ndo_uninit = chnl_net_uninit,
314 .ndo_start_xmit = chnl_net_start_xmit,
315};
316
317static void ipcaif_net_setup(struct net_device *dev)
318{
319 struct chnl_net *priv;
320 dev->netdev_ops = &netdev_ops;
321 dev->destructor = free_netdev;
322 dev->flags |= IFF_NOARP;
323 dev->flags |= IFF_POINTOPOINT;
324 dev->needed_headroom = CAIF_NEEDED_HEADROOM;
325 dev->needed_tailroom = CAIF_NEEDED_TAILROOM;
326 dev->mtu = SIZE_MTU;
327 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
328
329 priv = netdev_priv(dev);
330 priv->chnl.receive = chnl_recv_cb;
331 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
332 priv->netdev = dev;
333 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
334 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
335 priv->conn_req.priority = CAIF_PRIO_LOW;
336 /* Insert illegal value */
337 priv->conn_req.sockaddr.u.dgm.connection_id = -1;
338 priv->flowenabled = false;
339
340 ASSERT_RTNL();
341 init_waitqueue_head(&priv->netmgmt_wq);
342 list_add(&priv->list_field, &chnl_net_list);
343}
344
345
346static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
347{
348 struct chnl_net *priv;
349 u8 loop;
350 priv = netdev_priv(dev);
351 NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID,
352 priv->conn_req.sockaddr.u.dgm.connection_id);
353 NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID,
354 priv->conn_req.sockaddr.u.dgm.connection_id);
355 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
356 NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);
357
358
359 return 0;
360nla_put_failure:
361 return -EMSGSIZE;
362
363}
364
365static void caif_netlink_parms(struct nlattr *data[],
366 struct caif_connect_request *conn_req)
367{
368 if (!data) {
369 pr_warning("CAIF: %s: no params data found\n", __func__);
370 return;
371 }
372 if (data[IFLA_CAIF_IPV4_CONNID])
373 conn_req->sockaddr.u.dgm.connection_id =
374 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
375 if (data[IFLA_CAIF_IPV6_CONNID])
376 conn_req->sockaddr.u.dgm.connection_id =
377 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
378 if (data[IFLA_CAIF_LOOPBACK]) {
379 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
380 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
381 else
382 conn_req->protocol = CAIFPROTO_DATAGRAM;
383 }
384}
385
386static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
387 struct nlattr *tb[], struct nlattr *data[])
388{
389 int ret;
390 struct chnl_net *caifdev;
391 ASSERT_RTNL();
392 caifdev = netdev_priv(dev);
393 caif_netlink_parms(data, &caifdev->conn_req);
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394 dev_net_set(caifdev->netdev, src_net);
395
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396 ret = register_netdevice(dev);
397 if (ret)
398 pr_warning("CAIF: %s(): device rtml registration failed\n",
399 __func__);
400 return ret;
401}
402
403static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
404 struct nlattr *data[])
405{
406 struct chnl_net *caifdev;
407 ASSERT_RTNL();
408 caifdev = netdev_priv(dev);
409 caif_netlink_parms(data, &caifdev->conn_req);
410 netdev_state_change(dev);
411 return 0;
412}
413
414static size_t ipcaif_get_size(const struct net_device *dev)
415{
416 return
417 /* IFLA_CAIF_IPV4_CONNID */
418 nla_total_size(4) +
419 /* IFLA_CAIF_IPV6_CONNID */
420 nla_total_size(4) +
421 /* IFLA_CAIF_LOOPBACK */
422 nla_total_size(2) +
423 0;
424}
425
426static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
427 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
428 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
429 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
430};
431
432
433static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
434 .kind = "caif",
435 .priv_size = sizeof(struct chnl_net),
436 .setup = ipcaif_net_setup,
437 .maxtype = IFLA_CAIF_MAX,
438 .policy = ipcaif_policy,
439 .newlink = ipcaif_newlink,
440 .changelink = ipcaif_changelink,
441 .get_size = ipcaif_get_size,
442 .fill_info = ipcaif_fill_info,
443
444};
445
446static int __init chnl_init_module(void)
447{
448 return rtnl_link_register(&ipcaif_link_ops);
449}
450
451static void __exit chnl_exit_module(void)
452{
453 struct chnl_net *dev = NULL;
454 struct list_head *list_node;
455 struct list_head *_tmp;
456 rtnl_link_unregister(&ipcaif_link_ops);
457 rtnl_lock();
458 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
459 dev = list_entry(list_node, struct chnl_net, list_field);
460 list_del(list_node);
461 delete_device(dev);
462 }
463 rtnl_unlock();
464}
465
466module_init(chnl_init_module);
467module_exit(chnl_exit_module);