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
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>
12 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/if_arp.h>
17 #include <linux/net.h>
18 #include <linux/netdevice.h>
19 #include <linux/mutex.h>
20 #include <net/netns/generic.h>
21 #include <net/net_namespace.h>
22 #include <net/pkt_sched.h>
23 #include <net/caif/caif_device.h>
24 #include <net/caif/caif_layer.h>
25 #include <net/caif/cfpkt.h>
26 #include <net/caif/cfcnfg.h>
28 MODULE_LICENSE("GPL");
30 /* Used for local tracking of the CAIF net devices */
31 struct caif_device_entry {
33 struct list_head list;
34 struct net_device *netdev;
35 int __percpu *pcpu_refcnt;
38 struct caif_device_entry_list {
39 struct list_head list;
40 /* Protects simulanous deletes in list */
46 struct caif_device_entry_list caifdevs;
49 static int caif_net_id;
51 struct cfcnfg *get_cfcnfg(struct net *net)
53 struct caif_net *caifn;
55 caifn = net_generic(net, caif_net_id);
59 EXPORT_SYMBOL(get_cfcnfg);
61 static struct caif_device_entry_list *caif_device_list(struct net *net)
63 struct caif_net *caifn;
65 caifn = net_generic(net, caif_net_id);
67 return &caifn->caifdevs;
70 static void caifd_put(struct caif_device_entry *e)
72 irqsafe_cpu_dec(*e->pcpu_refcnt);
75 static void caifd_hold(struct caif_device_entry *e)
77 irqsafe_cpu_inc(*e->pcpu_refcnt);
80 static int caifd_refcnt_read(struct caif_device_entry *e)
83 for_each_possible_cpu(i)
84 refcnt += *per_cpu_ptr(e->pcpu_refcnt, i);
88 /* Allocate new CAIF device. */
89 static struct caif_device_entry *caif_device_alloc(struct net_device *dev)
91 struct caif_device_entry_list *caifdevs;
92 struct caif_device_entry *caifd;
94 caifdevs = caif_device_list(dev_net(dev));
97 caifd = kzalloc(sizeof(*caifd), GFP_ATOMIC);
100 caifd->pcpu_refcnt = alloc_percpu(int);
106 static struct caif_device_entry *caif_get(struct net_device *dev)
108 struct caif_device_entry_list *caifdevs =
109 caif_device_list(dev_net(dev));
110 struct caif_device_entry *caifd;
112 list_for_each_entry_rcu(caifd, &caifdevs->list, list) {
113 if (caifd->netdev == dev)
119 static int transmit(struct cflayer *layer, struct cfpkt *pkt)
122 struct caif_device_entry *caifd =
123 container_of(layer, struct caif_device_entry, layer);
126 skb = cfpkt_tonative(pkt);
127 skb->dev = caifd->netdev;
129 err = dev_queue_xmit(skb);
137 * Stuff received packets into the CAIF stack.
138 * On error, returns non-zero and releases the skb.
140 static int receive(struct sk_buff *skb, struct net_device *dev,
141 struct packet_type *pkttype, struct net_device *orig_dev)
144 struct caif_device_entry *caifd;
147 pkt = cfpkt_fromnative(CAIF_DIR_IN, skb);
150 caifd = caif_get(dev);
152 if (!caifd || !caifd->layer.up || !caifd->layer.up->receive ||
153 !netif_oper_up(caifd->netdev)) {
159 /* Hold reference to netdevice while using CAIF stack */
163 err = caifd->layer.up->receive(caifd->layer.up, pkt);
165 /* For -EILSEQ the packet is not freed so so it now */
169 /* Release reference to stack upwards */
174 static struct packet_type caif_packet_type __read_mostly = {
175 .type = cpu_to_be16(ETH_P_CAIF),
179 static void dev_flowctrl(struct net_device *dev, int on)
181 struct caif_device_entry *caifd;
185 caifd = caif_get(dev);
186 if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
194 caifd->layer.up->ctrlcmd(caifd->layer.up,
196 _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND :
197 _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
202 /* notify Caif of device events */
203 static int caif_device_notify(struct notifier_block *me, unsigned long what,
206 struct net_device *dev = arg;
207 struct caif_device_entry *caifd = NULL;
208 struct caif_dev_common *caifdev;
209 enum cfcnfg_phy_preference pref;
210 enum cfcnfg_phy_type phy_type;
212 struct caif_device_entry_list *caifdevs =
213 caif_device_list(dev_net(dev));
215 if (dev->type != ARPHRD_CAIF)
218 cfg = get_cfcnfg(dev_net(dev));
223 case NETDEV_REGISTER:
224 caifd = caif_device_alloc(dev);
228 caifdev = netdev_priv(dev);
229 caifdev->flowctrl = dev_flowctrl;
231 caifd->layer.transmit = transmit;
233 if (caifdev->use_frag)
234 phy_type = CFPHYTYPE_FRAG;
236 phy_type = CFPHYTYPE_CAIF;
238 switch (caifdev->link_select) {
239 case CAIF_LINK_HIGH_BANDW:
240 pref = CFPHYPREF_HIGH_BW;
242 case CAIF_LINK_LOW_LATENCY:
243 pref = CFPHYPREF_LOW_LAT;
246 pref = CFPHYPREF_HIGH_BW;
249 strncpy(caifd->layer.name, dev->name,
250 sizeof(caifd->layer.name) - 1);
251 caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0;
253 mutex_lock(&caifdevs->lock);
254 list_add_rcu(&caifd->list, &caifdevs->list);
256 cfcnfg_add_phy_layer(cfg,
263 mutex_unlock(&caifdevs->lock);
269 caifd = caif_get(dev);
275 cfcnfg_set_phy_state(cfg, &caifd->layer, true);
283 caifd = caif_get(dev);
284 if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
289 cfcnfg_set_phy_state(cfg, &caifd->layer, false);
293 caifd->layer.up->ctrlcmd(caifd->layer.up,
294 _CAIF_CTRLCMD_PHYIF_DOWN_IND,
299 case NETDEV_UNREGISTER:
300 mutex_lock(&caifdevs->lock);
302 caifd = caif_get(dev);
304 mutex_unlock(&caifdevs->lock);
307 list_del_rcu(&caifd->list);
310 * NETDEV_UNREGISTER is called repeatedly until all reference
311 * counts for the net-device are released. If references to
312 * caifd is taken, simply ignore NETDEV_UNREGISTER and wait for
313 * the next call to NETDEV_UNREGISTER.
315 * If any packets are in flight down the CAIF Stack,
316 * cfcnfg_del_phy_layer will return nonzero.
317 * If no packets are in flight, the CAIF Stack associated
318 * with the net-device un-registering is freed.
321 if (caifd_refcnt_read(caifd) != 0 ||
322 cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0) {
324 pr_info("Wait for device inuse\n");
325 /* Enrole device if CAIF Stack is still in use */
326 list_add_rcu(&caifd->list, &caifdevs->list);
327 mutex_unlock(&caifdevs->lock);
332 dev_put(caifd->netdev);
333 free_percpu(caifd->pcpu_refcnt);
336 mutex_unlock(&caifdevs->lock);
342 static struct notifier_block caif_device_notifier = {
343 .notifier_call = caif_device_notify,
347 /* Per-namespace Caif devices handling */
348 static int caif_init_net(struct net *net)
350 struct caif_net *caifn = net_generic(net, caif_net_id);
352 INIT_LIST_HEAD(&caifn->caifdevs.list);
353 mutex_init(&caifn->caifdevs.lock);
355 caifn->cfg = cfcnfg_create();
357 pr_warn("can't create cfcnfg\n");
364 static void caif_exit_net(struct net *net)
366 struct caif_device_entry *caifd, *tmp;
367 struct caif_device_entry_list *caifdevs =
368 caif_device_list(net);
372 mutex_lock(&caifdevs->lock);
374 cfg = get_cfcnfg(net);
376 mutex_unlock(&caifdevs->lock);
380 list_for_each_entry_safe(caifd, tmp, &caifdevs->list, list) {
382 list_del_rcu(&caifd->list);
383 cfcnfg_set_phy_state(cfg, &caifd->layer, false);
386 (caifd_refcnt_read(caifd) != 0 ||
387 cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0)) {
389 pr_info("Wait for device inuse\n");
394 dev_put(caifd->netdev);
395 free_percpu(caifd->pcpu_refcnt);
400 mutex_unlock(&caifdevs->lock);
404 static struct pernet_operations caif_net_ops = {
405 .init = caif_init_net,
406 .exit = caif_exit_net,
408 .size = sizeof(struct caif_net),
411 /* Initialize Caif devices list */
412 static int __init caif_device_init(void)
416 result = register_pernet_device(&caif_net_ops);
421 register_netdevice_notifier(&caif_device_notifier);
422 dev_add_pack(&caif_packet_type);
427 static void __exit caif_device_exit(void)
429 unregister_pernet_device(&caif_net_ops);
430 unregister_netdevice_notifier(&caif_device_notifier);
431 dev_remove_pack(&caif_packet_type);
434 module_init(caif_device_init);
435 module_exit(caif_device_exit);