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/kernel.h>
15 #include <linux/if_arp.h>
16 #include <linux/net.h>
17 #include <linux/netdevice.h>
18 #include <linux/mutex.h>
19 #include <linux/module.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_KERNEL
);
100 caifd
->pcpu_refcnt
= alloc_percpu(int);
101 if (!caifd
->pcpu_refcnt
) {
110 static struct caif_device_entry
*caif_get(struct net_device
*dev
)
112 struct caif_device_entry_list
*caifdevs
=
113 caif_device_list(dev_net(dev
));
114 struct caif_device_entry
*caifd
;
116 list_for_each_entry_rcu(caifd
, &caifdevs
->list
, list
) {
117 if (caifd
->netdev
== dev
)
123 static int transmit(struct cflayer
*layer
, struct cfpkt
*pkt
)
126 struct caif_device_entry
*caifd
=
127 container_of(layer
, struct caif_device_entry
, layer
);
130 skb
= cfpkt_tonative(pkt
);
131 skb
->dev
= caifd
->netdev
;
133 err
= dev_queue_xmit(skb
);
141 * Stuff received packets into the CAIF stack.
142 * On error, returns non-zero and releases the skb.
144 static int receive(struct sk_buff
*skb
, struct net_device
*dev
,
145 struct packet_type
*pkttype
, struct net_device
*orig_dev
)
148 struct caif_device_entry
*caifd
;
151 pkt
= cfpkt_fromnative(CAIF_DIR_IN
, skb
);
154 caifd
= caif_get(dev
);
156 if (!caifd
|| !caifd
->layer
.up
|| !caifd
->layer
.up
->receive
||
157 !netif_oper_up(caifd
->netdev
)) {
163 /* Hold reference to netdevice while using CAIF stack */
167 err
= caifd
->layer
.up
->receive(caifd
->layer
.up
, pkt
);
169 /* For -EILSEQ the packet is not freed so so it now */
173 /* Release reference to stack upwards */
178 static struct packet_type caif_packet_type __read_mostly
= {
179 .type
= cpu_to_be16(ETH_P_CAIF
),
183 static void dev_flowctrl(struct net_device
*dev
, int on
)
185 struct caif_device_entry
*caifd
;
189 caifd
= caif_get(dev
);
190 if (!caifd
|| !caifd
->layer
.up
|| !caifd
->layer
.up
->ctrlcmd
) {
198 caifd
->layer
.up
->ctrlcmd(caifd
->layer
.up
,
200 _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND
:
201 _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND
,
206 /* notify Caif of device events */
207 static int caif_device_notify(struct notifier_block
*me
, unsigned long what
,
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
;
214 enum cfcnfg_phy_type phy_type
;
216 struct caif_device_entry_list
*caifdevs
;
218 if (dev
->type
!= ARPHRD_CAIF
)
221 cfg
= get_cfcnfg(dev_net(dev
));
225 caifdevs
= caif_device_list(dev_net(dev
));
228 case NETDEV_REGISTER
:
229 caifd
= caif_device_alloc(dev
);
233 caifdev
= netdev_priv(dev
);
234 caifdev
->flowctrl
= dev_flowctrl
;
236 caifd
->layer
.transmit
= transmit
;
238 if (caifdev
->use_frag
)
239 phy_type
= CFPHYTYPE_FRAG
;
241 phy_type
= CFPHYTYPE_CAIF
;
243 switch (caifdev
->link_select
) {
244 case CAIF_LINK_HIGH_BANDW
:
245 pref
= CFPHYPREF_HIGH_BW
;
247 case CAIF_LINK_LOW_LATENCY
:
248 pref
= CFPHYPREF_LOW_LAT
;
251 pref
= CFPHYPREF_HIGH_BW
;
254 strncpy(caifd
->layer
.name
, dev
->name
,
255 sizeof(caifd
->layer
.name
) - 1);
256 caifd
->layer
.name
[sizeof(caifd
->layer
.name
) - 1] = 0;
258 mutex_lock(&caifdevs
->lock
);
259 list_add_rcu(&caifd
->list
, &caifdevs
->list
);
261 cfcnfg_add_phy_layer(cfg
,
268 mutex_unlock(&caifdevs
->lock
);
274 caifd
= caif_get(dev
);
280 cfcnfg_set_phy_state(cfg
, &caifd
->layer
, true);
288 caifd
= caif_get(dev
);
289 if (!caifd
|| !caifd
->layer
.up
|| !caifd
->layer
.up
->ctrlcmd
) {
294 cfcnfg_set_phy_state(cfg
, &caifd
->layer
, false);
298 caifd
->layer
.up
->ctrlcmd(caifd
->layer
.up
,
299 _CAIF_CTRLCMD_PHYIF_DOWN_IND
,
304 case NETDEV_UNREGISTER
:
305 mutex_lock(&caifdevs
->lock
);
307 caifd
= caif_get(dev
);
309 mutex_unlock(&caifdevs
->lock
);
312 list_del_rcu(&caifd
->list
);
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.
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.
326 if (caifd_refcnt_read(caifd
) != 0 ||
327 cfcnfg_del_phy_layer(cfg
, &caifd
->layer
) != 0) {
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
);
337 dev_put(caifd
->netdev
);
338 free_percpu(caifd
->pcpu_refcnt
);
341 mutex_unlock(&caifdevs
->lock
);
347 static struct notifier_block caif_device_notifier
= {
348 .notifier_call
= caif_device_notify
,
352 /* Per-namespace Caif devices handling */
353 static int caif_init_net(struct net
*net
)
355 struct caif_net
*caifn
= net_generic(net
, caif_net_id
);
357 INIT_LIST_HEAD(&caifn
->caifdevs
.list
);
358 mutex_init(&caifn
->caifdevs
.lock
);
360 caifn
->cfg
= cfcnfg_create();
362 pr_warn("can't create cfcnfg\n");
369 static void caif_exit_net(struct net
*net
)
371 struct caif_device_entry
*caifd
, *tmp
;
372 struct caif_device_entry_list
*caifdevs
=
373 caif_device_list(net
);
377 mutex_lock(&caifdevs
->lock
);
379 cfg
= get_cfcnfg(net
);
381 mutex_unlock(&caifdevs
->lock
);
385 list_for_each_entry_safe(caifd
, tmp
, &caifdevs
->list
, list
) {
387 list_del_rcu(&caifd
->list
);
388 cfcnfg_set_phy_state(cfg
, &caifd
->layer
, false);
391 (caifd_refcnt_read(caifd
) != 0 ||
392 cfcnfg_del_phy_layer(cfg
, &caifd
->layer
) != 0)) {
394 pr_info("Wait for device inuse\n");
399 dev_put(caifd
->netdev
);
400 free_percpu(caifd
->pcpu_refcnt
);
405 mutex_unlock(&caifdevs
->lock
);
409 static struct pernet_operations caif_net_ops
= {
410 .init
= caif_init_net
,
411 .exit
= caif_exit_net
,
413 .size
= sizeof(struct caif_net
),
416 /* Initialize Caif devices list */
417 static int __init
caif_device_init(void)
421 result
= register_pernet_device(&caif_net_ops
);
426 register_netdevice_notifier(&caif_device_notifier
);
427 dev_add_pack(&caif_packet_type
);
432 static void __exit
caif_device_exit(void)
434 unregister_pernet_device(&caif_net_ops
);
435 unregister_netdevice_notifier(&caif_device_notifier
);
436 dev_remove_pack(&caif_packet_type
);
439 module_init(caif_device_init
);
440 module_exit(caif_device_exit
);