blob: f1fa1f6e658d4dc84ca6eea2abceb6be6d3e8283 [file] [log] [blame]
Sjur Braendelandc72dfae2010-03-30 13:56:25 +00001/*
2 * CAIF Interface registration.
3 * Copyright (C) ST-Ericsson AB 2010
4 * Author: Sjur Brendeland/sjur.brandeland@stericsson.com
5 * License terms: GNU General Public License (GPL) version 2
6 *
7 * Borrowed heavily from file: pn_dev.c. Thanks to
8 * Remi Denis-Courmont <remi.denis-courmont@nokia.com>
9 * and Sakari Ailus <sakari.ailus@nokia.com>
10 */
11
Joe Perchesb31fa5b2010-09-05 21:31:11 +000012#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
13
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000014#include <linux/kernel.h>
15#include <linux/if_arp.h>
16#include <linux/net.h>
17#include <linux/netdevice.h>
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000018#include <linux/mutex.h>
Paul Gortmaker3a9a2312011-05-27 09:12:25 -040019#include <linux/module.h>
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000020#include <net/netns/generic.h>
21#include <net/net_namespace.h>
22#include <net/pkt_sched.h>
23#include <net/caif/caif_device.h>
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000024#include <net/caif/caif_layer.h>
25#include <net/caif/cfpkt.h>
26#include <net/caif/cfcnfg.h>
27
28MODULE_LICENSE("GPL");
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000029
30/* Used for local tracking of the CAIF net devices */
31struct caif_device_entry {
32 struct cflayer layer;
33 struct list_head list;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000034 struct net_device *netdev;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000035 int __percpu *pcpu_refcnt;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000036};
37
38struct caif_device_entry_list {
39 struct list_head list;
40 /* Protects simulanous deletes in list */
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000041 struct mutex lock;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000042};
43
44struct caif_net {
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +000045 struct cfcnfg *cfg;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000046 struct caif_device_entry_list caifdevs;
47};
48
49static int caif_net_id;
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +000050
51struct cfcnfg *get_cfcnfg(struct net *net)
52{
53 struct caif_net *caifn;
54 BUG_ON(!net);
55 caifn = net_generic(net, caif_net_id);
56 BUG_ON(!caifn);
57 return caifn->cfg;
58}
59EXPORT_SYMBOL(get_cfcnfg);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000060
61static struct caif_device_entry_list *caif_device_list(struct net *net)
62{
63 struct caif_net *caifn;
64 BUG_ON(!net);
65 caifn = net_generic(net, caif_net_id);
66 BUG_ON(!caifn);
67 return &caifn->caifdevs;
68}
69
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000070static void caifd_put(struct caif_device_entry *e)
71{
72 irqsafe_cpu_dec(*e->pcpu_refcnt);
73}
74
75static void caifd_hold(struct caif_device_entry *e)
76{
77 irqsafe_cpu_inc(*e->pcpu_refcnt);
78}
79
80static int caifd_refcnt_read(struct caif_device_entry *e)
81{
82 int i, refcnt = 0;
83 for_each_possible_cpu(i)
84 refcnt += *per_cpu_ptr(e->pcpu_refcnt, i);
85 return refcnt;
86}
87
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000088/* Allocate new CAIF device. */
89static struct caif_device_entry *caif_device_alloc(struct net_device *dev)
90{
91 struct caif_device_entry_list *caifdevs;
92 struct caif_device_entry *caifd;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000093
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000094 caifdevs = caif_device_list(dev_net(dev));
95 BUG_ON(!caifdevs);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +000096
Eric Dumazet4fb66b82011-09-02 02:19:23 +000097 caifd = kzalloc(sizeof(*caifd), GFP_KERNEL);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +000098 if (!caifd)
99 return NULL;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000100 caifd->pcpu_refcnt = alloc_percpu(int);
Eric Dumazet4fb66b82011-09-02 02:19:23 +0000101 if (!caifd->pcpu_refcnt) {
102 kfree(caifd);
103 return NULL;
104 }
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000105 caifd->netdev = dev;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000106 dev_hold(dev);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000107 return caifd;
108}
109
110static struct caif_device_entry *caif_get(struct net_device *dev)
111{
112 struct caif_device_entry_list *caifdevs =
113 caif_device_list(dev_net(dev));
114 struct caif_device_entry *caifd;
115 BUG_ON(!caifdevs);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000116 list_for_each_entry_rcu(caifd, &caifdevs->list, list) {
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000117 if (caifd->netdev == dev)
118 return caifd;
119 }
120 return NULL;
121}
122
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000123static int transmit(struct cflayer *layer, struct cfpkt *pkt)
124{
sjur.brandeland@stericsson.comc85c2952011-05-13 02:44:06 +0000125 int err;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000126 struct caif_device_entry *caifd =
127 container_of(layer, struct caif_device_entry, layer);
Sjur Brændeland4dd820c2011-04-11 10:43:51 +0000128 struct sk_buff *skb;
129
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000130 skb = cfpkt_tonative(pkt);
131 skb->dev = caifd->netdev;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000132
sjur.brandeland@stericsson.comc85c2952011-05-13 02:44:06 +0000133 err = dev_queue_xmit(skb);
134 if (err > 0)
135 err = -EIO;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000136
sjur.brandeland@stericsson.comc85c2952011-05-13 02:44:06 +0000137 return err;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000138}
139
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000140/*
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000141 * Stuff received packets into the CAIF stack.
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000142 * On error, returns non-zero and releases the skb.
143 */
144static int receive(struct sk_buff *skb, struct net_device *dev,
145 struct packet_type *pkttype, struct net_device *orig_dev)
146{
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000147 struct cfpkt *pkt;
148 struct caif_device_entry *caifd;
sjur.brandeland@stericsson.com69c867c92011-05-22 11:18:54 +0000149 int err;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000150
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000151 pkt = cfpkt_fromnative(CAIF_DIR_IN, skb);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000152
153 rcu_read_lock();
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000154 caifd = caif_get(dev);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000155
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000156 if (!caifd || !caifd->layer.up || !caifd->layer.up->receive ||
157 !netif_oper_up(caifd->netdev)) {
158 rcu_read_unlock();
159 kfree_skb(skb);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000160 return NET_RX_DROP;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000161 }
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000162
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000163 /* Hold reference to netdevice while using CAIF stack */
164 caifd_hold(caifd);
165 rcu_read_unlock();
166
sjur.brandeland@stericsson.com69c867c92011-05-22 11:18:54 +0000167 err = caifd->layer.up->receive(caifd->layer.up, pkt);
168
169 /* For -EILSEQ the packet is not freed so so it now */
170 if (err == -EILSEQ)
171 cfpkt_destroy(pkt);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000172
173 /* Release reference to stack upwards */
174 caifd_put(caifd);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000175 return 0;
176}
177
178static struct packet_type caif_packet_type __read_mostly = {
179 .type = cpu_to_be16(ETH_P_CAIF),
180 .func = receive,
181};
182
183static void dev_flowctrl(struct net_device *dev, int on)
184{
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000185 struct caif_device_entry *caifd;
186
187 rcu_read_lock();
188
189 caifd = caif_get(dev);
190 if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
191 rcu_read_unlock();
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000192 return;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000193 }
194
195 caifd_hold(caifd);
196 rcu_read_unlock();
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000197
198 caifd->layer.up->ctrlcmd(caifd->layer.up,
199 on ?
200 _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND :
201 _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
202 caifd->layer.id);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000203 caifd_put(caifd);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000204}
205
206/* notify Caif of device events */
207static int caif_device_notify(struct notifier_block *me, unsigned long what,
208 void *arg)
209{
210 struct net_device *dev = arg;
211 struct caif_device_entry *caifd = NULL;
212 struct caif_dev_common *caifdev;
213 enum cfcnfg_phy_preference pref;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000214 enum cfcnfg_phy_type phy_type;
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000215 struct cfcnfg *cfg;
David Woodhouse08613e42011-10-24 21:25:21 +0000216 struct caif_device_entry_list *caifdevs;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000217
218 if (dev->type != ARPHRD_CAIF)
219 return 0;
220
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000221 cfg = get_cfcnfg(dev_net(dev));
222 if (cfg == NULL)
223 return 0;
224
David Woodhouse08613e42011-10-24 21:25:21 +0000225 caifdevs = caif_device_list(dev_net(dev));
226
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000227 switch (what) {
228 case NETDEV_REGISTER:
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000229 caifd = caif_device_alloc(dev);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000230 if (!caifd)
231 return 0;
232
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000233 caifdev = netdev_priv(dev);
234 caifdev->flowctrl = dev_flowctrl;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000235
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000236 caifd->layer.transmit = transmit;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000237
238 if (caifdev->use_frag)
239 phy_type = CFPHYTYPE_FRAG;
240 else
241 phy_type = CFPHYTYPE_CAIF;
242
243 switch (caifdev->link_select) {
244 case CAIF_LINK_HIGH_BANDW:
Sjur Braendeland2c485202010-04-28 08:54:40 +0000245 pref = CFPHYPREF_HIGH_BW;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000246 break;
247 case CAIF_LINK_LOW_LATENCY:
Sjur Braendeland2c485202010-04-28 08:54:40 +0000248 pref = CFPHYPREF_LOW_LAT;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000249 break;
250 default:
251 pref = CFPHYPREF_HIGH_BW;
252 break;
253 }
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000254 strncpy(caifd->layer.name, dev->name,
255 sizeof(caifd->layer.name) - 1);
256 caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0;
257
258 mutex_lock(&caifdevs->lock);
259 list_add_rcu(&caifd->list, &caifdevs->list);
260
Stephen Hemminger73d6ac62011-04-11 10:43:50 +0000261 cfcnfg_add_phy_layer(cfg,
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000262 phy_type,
263 dev,
264 &caifd->layer,
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000265 pref,
266 caifdev->use_fcs,
267 caifdev->use_stx);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000268 mutex_unlock(&caifdevs->lock);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000269 break;
270
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000271 case NETDEV_UP:
272 rcu_read_lock();
273
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000274 caifd = caif_get(dev);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000275 if (caifd == NULL) {
276 rcu_read_unlock();
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000277 break;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000278 }
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000279
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000280 cfcnfg_set_phy_state(cfg, &caifd->layer, true);
281 rcu_read_unlock();
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000282
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000283 break;
284
285 case NETDEV_DOWN:
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000286 rcu_read_lock();
287
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000288 caifd = caif_get(dev);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000289 if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
290 rcu_read_unlock();
291 return -EINVAL;
292 }
293
294 cfcnfg_set_phy_state(cfg, &caifd->layer, false);
295 caifd_hold(caifd);
296 rcu_read_unlock();
297
298 caifd->layer.up->ctrlcmd(caifd->layer.up,
299 _CAIF_CTRLCMD_PHYIF_DOWN_IND,
300 caifd->layer.id);
301 caifd_put(caifd);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000302 break;
303
304 case NETDEV_UNREGISTER:
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000305 mutex_lock(&caifdevs->lock);
306
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000307 caifd = caif_get(dev);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000308 if (caifd == NULL) {
309 mutex_unlock(&caifdevs->lock);
André Carvalho de Matosf2527ec2010-11-01 11:52:47 +0000310 break;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000311 }
312 list_del_rcu(&caifd->list);
313
314 /*
315 * NETDEV_UNREGISTER is called repeatedly until all reference
316 * counts for the net-device are released. If references to
317 * caifd is taken, simply ignore NETDEV_UNREGISTER and wait for
318 * the next call to NETDEV_UNREGISTER.
319 *
320 * If any packets are in flight down the CAIF Stack,
321 * cfcnfg_del_phy_layer will return nonzero.
322 * If no packets are in flight, the CAIF Stack associated
323 * with the net-device un-registering is freed.
324 */
325
326 if (caifd_refcnt_read(caifd) != 0 ||
327 cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0) {
328
329 pr_info("Wait for device inuse\n");
330 /* Enrole device if CAIF Stack is still in use */
331 list_add_rcu(&caifd->list, &caifdevs->list);
332 mutex_unlock(&caifdevs->lock);
333 break;
334 }
335
336 synchronize_rcu();
337 dev_put(caifd->netdev);
338 free_percpu(caifd->pcpu_refcnt);
339 kfree(caifd);
340
341 mutex_unlock(&caifdevs->lock);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000342 break;
343 }
344 return 0;
345}
346
347static struct notifier_block caif_device_notifier = {
348 .notifier_call = caif_device_notify,
349 .priority = 0,
350};
351
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000352/* Per-namespace Caif devices handling */
353static int caif_init_net(struct net *net)
354{
355 struct caif_net *caifn = net_generic(net, caif_net_id);
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000356 BUG_ON(!caifn);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000357 INIT_LIST_HEAD(&caifn->caifdevs.list);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000358 mutex_init(&caifn->caifdevs.lock);
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000359
360 caifn->cfg = cfcnfg_create();
361 if (!caifn->cfg) {
362 pr_warn("can't create cfcnfg\n");
363 return -ENOMEM;
364 }
365
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000366 return 0;
367}
368
369static void caif_exit_net(struct net *net)
370{
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000371 struct caif_device_entry *caifd, *tmp;
372 struct caif_device_entry_list *caifdevs =
373 caif_device_list(net);
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000374 struct cfcnfg *cfg;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000375
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000376 rtnl_lock();
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000377 mutex_lock(&caifdevs->lock);
378
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000379 cfg = get_cfcnfg(net);
380 if (cfg == NULL) {
381 mutex_unlock(&caifdevs->lock);
382 return;
383 }
384
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000385 list_for_each_entry_safe(caifd, tmp, &caifdevs->list, list) {
386 int i = 0;
387 list_del_rcu(&caifd->list);
388 cfcnfg_set_phy_state(cfg, &caifd->layer, false);
389
390 while (i < 10 &&
391 (caifd_refcnt_read(caifd) != 0 ||
392 cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0)) {
393
394 pr_info("Wait for device inuse\n");
395 msleep(250);
396 i++;
397 }
398 synchronize_rcu();
399 dev_put(caifd->netdev);
400 free_percpu(caifd->pcpu_refcnt);
401 kfree(caifd);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000402 }
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000403 cfcnfg_remove(cfg);
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000404
405 mutex_unlock(&caifdevs->lock);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000406 rtnl_unlock();
407}
408
409static struct pernet_operations caif_net_ops = {
410 .init = caif_init_net,
411 .exit = caif_exit_net,
412 .id = &caif_net_id,
413 .size = sizeof(struct caif_net),
414};
415
416/* Initialize Caif devices list */
417static int __init caif_device_init(void)
418{
419 int result;
sjur.brandeland@stericsson.combd30ce42011-05-13 02:44:00 +0000420
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000421 result = register_pernet_device(&caif_net_ops);
422
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000423 if (result)
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000424 return result;
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000425
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000426 register_netdevice_notifier(&caif_device_notifier);
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000427 dev_add_pack(&caif_packet_type);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000428
429 return result;
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000430}
431
432static void __exit caif_device_exit(void)
433{
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000434 unregister_pernet_device(&caif_net_ops);
435 unregister_netdevice_notifier(&caif_device_notifier);
sjur.brandeland@stericsson.combee925d2011-05-13 02:44:05 +0000436 dev_remove_pack(&caif_packet_type);
Sjur Braendelandc72dfae2010-03-30 13:56:25 +0000437}
438
439module_init(caif_device_init);
440module_exit(caif_device_exit);