[deliverable/linux.git] / net / caif / caif_dev.c

/*
 * CAIF Interface registration.
 * Copyright (C) ST-Ericsson AB 2010
 * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
 * License terms: GNU General Public License (GPL) version 2
 *
 * Borrowed heavily from file: pn_dev.c. Thanks to
 *  Remi Denis-Courmont <remi.denis-courmont@nokia.com>
 *  and Sakari Ailus <sakari.ailus@nokia.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

#include <linux/kernel.h>
#include <linux/if_arp.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <net/netns/generic.h>
#include <net/net_namespace.h>
#include <net/pkt_sched.h>
#include <net/caif/caif_device.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfpkt.h>
#include <net/caif/cfcnfg.h>

MODULE_LICENSE("GPL");

/* Used for local tracking of the CAIF net devices */
struct caif_device_entry {
	struct cflayer layer;
	struct list_head list;
	struct net_device *netdev;
	int __percpu *pcpu_refcnt;
};

struct caif_device_entry_list {
	struct list_head list;
	/* Protects simulanous deletes in list */
	struct mutex lock;
};

struct caif_net {
	struct cfcnfg *cfg;
	struct caif_device_entry_list caifdevs;
};

static int caif_net_id;

struct cfcnfg *get_cfcnfg(struct net *net)
{
	struct caif_net *caifn;
	BUG_ON(!net);
	caifn = net_generic(net, caif_net_id);
	BUG_ON(!caifn);
	return caifn->cfg;
}
EXPORT_SYMBOL(get_cfcnfg);

static struct caif_device_entry_list *caif_device_list(struct net *net)
{
	struct caif_net *caifn;
	BUG_ON(!net);
	caifn = net_generic(net, caif_net_id);
	BUG_ON(!caifn);
	return &caifn->caifdevs;
}

static void caifd_put(struct caif_device_entry *e)
{
	irqsafe_cpu_dec(*e->pcpu_refcnt);
}

static void caifd_hold(struct caif_device_entry *e)
{
	irqsafe_cpu_inc(*e->pcpu_refcnt);
}

static int caifd_refcnt_read(struct caif_device_entry *e)
{
	int i, refcnt = 0;
	for_each_possible_cpu(i)
		refcnt += *per_cpu_ptr(e->pcpu_refcnt, i);
	return refcnt;
}

/* Allocate new CAIF device. */
static struct caif_device_entry *caif_device_alloc(struct net_device *dev)
{
	struct caif_device_entry_list *caifdevs;
	struct caif_device_entry *caifd;

	caifdevs = caif_device_list(dev_net(dev));
	BUG_ON(!caifdevs);

	caifd = kzalloc(sizeof(*caifd), GFP_KERNEL);
	if (!caifd)
		return NULL;
	caifd->pcpu_refcnt = alloc_percpu(int);
	if (!caifd->pcpu_refcnt) {
		kfree(caifd);
		return NULL;
	}
	caifd->netdev = dev;
	dev_hold(dev);
	return caifd;
}

static struct caif_device_entry *caif_get(struct net_device *dev)
{
	struct caif_device_entry_list *caifdevs =
	    caif_device_list(dev_net(dev));
	struct caif_device_entry *caifd;
	BUG_ON(!caifdevs);
	list_for_each_entry_rcu(caifd, &caifdevs->list, list) {
		if (caifd->netdev == dev)
			return caifd;
	}
	return NULL;
}

static int transmit(struct cflayer *layer, struct cfpkt *pkt)
{
	int err;
	struct caif_device_entry *caifd =
	    container_of(layer, struct caif_device_entry, layer);
	struct sk_buff *skb;

	skb = cfpkt_tonative(pkt);
	skb->dev = caifd->netdev;

	err = dev_queue_xmit(skb);
	if (err > 0)
		err = -EIO;

	return err;
}

/*
 * Stuff received packets into the CAIF stack.
 * On error, returns non-zero and releases the skb.
 */
static int receive(struct sk_buff *skb, struct net_device *dev,
		   struct packet_type *pkttype, struct net_device *orig_dev)
{
	struct cfpkt *pkt;
	struct caif_device_entry *caifd;
	int err;

	pkt = cfpkt_fromnative(CAIF_DIR_IN, skb);

	rcu_read_lock();
	caifd = caif_get(dev);

	if (!caifd || !caifd->layer.up || !caifd->layer.up->receive ||
			!netif_oper_up(caifd->netdev)) {
		rcu_read_unlock();
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	/* Hold reference to netdevice while using CAIF stack */
	caifd_hold(caifd);
	rcu_read_unlock();

	err = caifd->layer.up->receive(caifd->layer.up, pkt);

	/* For -EILSEQ the packet is not freed so so it now */
	if (err == -EILSEQ)
		cfpkt_destroy(pkt);

	/* Release reference to stack upwards */
	caifd_put(caifd);
	return 0;
}

static struct packet_type caif_packet_type __read_mostly = {
	.type = cpu_to_be16(ETH_P_CAIF),
	.func = receive,
};

static void dev_flowctrl(struct net_device *dev, int on)
{
	struct caif_device_entry *caifd;

	rcu_read_lock();

	caifd = caif_get(dev);
	if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
		rcu_read_unlock();
		return;
	}

	caifd_hold(caifd);
	rcu_read_unlock();

	caifd->layer.up->ctrlcmd(caifd->layer.up,
				 on ?
				 _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND :
				 _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
				 caifd->layer.id);
	caifd_put(caifd);
}

/* notify Caif of device events */
static int caif_device_notify(struct notifier_block *me, unsigned long what,
			      void *arg)
{
	struct net_device *dev = arg;
	struct caif_device_entry *caifd = NULL;
	struct caif_dev_common *caifdev;
	enum cfcnfg_phy_preference pref;
	enum cfcnfg_phy_type phy_type;
	struct cfcnfg *cfg;
	struct caif_device_entry_list *caifdevs;

	if (dev->type != ARPHRD_CAIF)
		return 0;

	cfg = get_cfcnfg(dev_net(dev));
	if (cfg == NULL)
		return 0;

	caifdevs = caif_device_list(dev_net(dev));

	switch (what) {
	case NETDEV_REGISTER:
		caifd = caif_device_alloc(dev);
		if (!caifd)
			return 0;

		caifdev = netdev_priv(dev);
		caifdev->flowctrl = dev_flowctrl;

		caifd->layer.transmit = transmit;

		if (caifdev->use_frag)
			phy_type = CFPHYTYPE_FRAG;
		else
			phy_type = CFPHYTYPE_CAIF;

		switch (caifdev->link_select) {
		case CAIF_LINK_HIGH_BANDW:
			pref = CFPHYPREF_HIGH_BW;
			break;
		case CAIF_LINK_LOW_LATENCY:
			pref = CFPHYPREF_LOW_LAT;
			break;
		default:
			pref = CFPHYPREF_HIGH_BW;
			break;
		}
		strncpy(caifd->layer.name, dev->name,
			sizeof(caifd->layer.name) - 1);
		caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0;

		mutex_lock(&caifdevs->lock);
		list_add_rcu(&caifd->list, &caifdevs->list);

		cfcnfg_add_phy_layer(cfg,
				     phy_type,
				     dev,
				     &caifd->layer,
				     pref,
				     caifdev->use_fcs,
				     caifdev->use_stx);
		mutex_unlock(&caifdevs->lock);
		break;

	case NETDEV_UP:
		rcu_read_lock();

		caifd = caif_get(dev);
		if (caifd == NULL) {
			rcu_read_unlock();
			break;
		}

		cfcnfg_set_phy_state(cfg, &caifd->layer, true);
		rcu_read_unlock();

		break;

	case NETDEV_DOWN:
		rcu_read_lock();

		caifd = caif_get(dev);
		if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) {
			rcu_read_unlock();
			return -EINVAL;
		}

		cfcnfg_set_phy_state(cfg, &caifd->layer, false);
		caifd_hold(caifd);
		rcu_read_unlock();

		caifd->layer.up->ctrlcmd(caifd->layer.up,
					 _CAIF_CTRLCMD_PHYIF_DOWN_IND,
					 caifd->layer.id);
		caifd_put(caifd);
		break;

	case NETDEV_UNREGISTER:
		mutex_lock(&caifdevs->lock);

		caifd = caif_get(dev);
		if (caifd == NULL) {
			mutex_unlock(&caifdevs->lock);
			break;
		}
		list_del_rcu(&caifd->list);

		/*
		 * NETDEV_UNREGISTER is called repeatedly until all reference
		 * counts for the net-device are released. If references to
		 * caifd is taken, simply ignore NETDEV_UNREGISTER and wait for
		 * the next call to NETDEV_UNREGISTER.
		 *
		 * If any packets are in flight down the CAIF Stack,
		 * cfcnfg_del_phy_layer will return nonzero.
		 * If no packets are in flight, the CAIF Stack associated
		 * with the net-device un-registering is freed.
		 */

		if (caifd_refcnt_read(caifd) != 0 ||
			cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0) {

			pr_info("Wait for device inuse\n");
			/* Enrole device if CAIF Stack is still in use */
			list_add_rcu(&caifd->list, &caifdevs->list);
			mutex_unlock(&caifdevs->lock);
			break;
		}

		synchronize_rcu();
		dev_put(caifd->netdev);
		free_percpu(caifd->pcpu_refcnt);
		kfree(caifd);

		mutex_unlock(&caifdevs->lock);
		break;
	}
	return 0;
}

static struct notifier_block caif_device_notifier = {
	.notifier_call = caif_device_notify,
	.priority = 0,
};

/* Per-namespace Caif devices handling */
static int caif_init_net(struct net *net)
{
	struct caif_net *caifn = net_generic(net, caif_net_id);
	BUG_ON(!caifn);
	INIT_LIST_HEAD(&caifn->caifdevs.list);
	mutex_init(&caifn->caifdevs.lock);

	caifn->cfg = cfcnfg_create();
	if (!caifn->cfg) {
		pr_warn("can't create cfcnfg\n");
		return -ENOMEM;
	}

	return 0;
}

static void caif_exit_net(struct net *net)
{
	struct caif_device_entry *caifd, *tmp;
	struct caif_device_entry_list *caifdevs =
	    caif_device_list(net);
	struct cfcnfg *cfg;

	rtnl_lock();
	mutex_lock(&caifdevs->lock);

	cfg = get_cfcnfg(net);
	if (cfg == NULL) {
		mutex_unlock(&caifdevs->lock);
		return;
	}

	list_for_each_entry_safe(caifd, tmp, &caifdevs->list, list) {
		int i = 0;
		list_del_rcu(&caifd->list);
		cfcnfg_set_phy_state(cfg, &caifd->layer, false);

		while (i < 10 &&
			(caifd_refcnt_read(caifd) != 0 ||
			cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0)) {

			pr_info("Wait for device inuse\n");
			msleep(250);
			i++;
		}
		synchronize_rcu();
		dev_put(caifd->netdev);
		free_percpu(caifd->pcpu_refcnt);
		kfree(caifd);
	}
	cfcnfg_remove(cfg);

	mutex_unlock(&caifdevs->lock);
	rtnl_unlock();
}

static struct pernet_operations caif_net_ops = {
	.init = caif_init_net,
	.exit = caif_exit_net,
	.id   = &caif_net_id,
	.size = sizeof(struct caif_net),
};

/* Initialize Caif devices list */
static int __init caif_device_init(void)
{
	int result;

	result = register_pernet_device(&caif_net_ops);

	if (result)
		return result;

	register_netdevice_notifier(&caif_device_notifier);
	dev_add_pack(&caif_packet_type);

	return result;
}

static void __exit caif_device_exit(void)
{
	unregister_pernet_device(&caif_net_ops);
	unregister_netdevice_notifier(&caif_device_notifier);
	dev_remove_pack(&caif_packet_type);
}

module_init(caif_device_init);
module_exit(caif_device_exit);
Commit	Line	Data
c72dfae2 SB	1	/*
	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
b31fa5ba JP	12	#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
b31fa5ba JP	13
c72dfae2 SB	14	#include <linux/kernel.h>
	15	#include <linux/if_arp.h>
	16	#include <linux/net.h>
	17	#include <linux/netdevice.h>
bd30ce4b	18	#include <linux/mutex.h>
3a9a231d	19	#include <linux/module.h>
c72dfae2 SB	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>
c72dfae2 SB	24	#include <net/caif/caif_layer.h>
	25	#include <net/caif/cfpkt.h>
	26	#include <net/caif/cfcnfg.h>
	27
	28	MODULE_LICENSE("GPL");
c72dfae2 SB	29
	30	/* Used for local tracking of the CAIF net devices */
	31	struct caif_device_entry {
	32	struct cflayer layer;
	33	struct list_head list;
c72dfae2	34	struct net_device *netdev;
bd30ce4b	35	int __percpu *pcpu_refcnt;
c72dfae2 SB	36	};
	37
	38	struct caif_device_entry_list {
	39	struct list_head list;
	40	/* Protects simulanous deletes in list */
bd30ce4b	41	struct mutex lock;
c72dfae2 SB	42	};
	43
	44	struct caif_net {
bee925db	45	struct cfcnfg *cfg;
c72dfae2 SB	46	struct caif_device_entry_list caifdevs;
	47	};
	48
	49	static int caif_net_id;
bee925db	50
	51	struct 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	}
	59	EXPORT_SYMBOL(get_cfcnfg);
c72dfae2 SB	60
	61	static 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
bd30ce4b	70	static void caifd_put(struct caif_device_entry *e)
	71	{
	72	irqsafe_cpu_dec(*e->pcpu_refcnt);
	73	}
	74
	75	static void caifd_hold(struct caif_device_entry *e)
	76	{
	77	irqsafe_cpu_inc(*e->pcpu_refcnt);
	78	}
	79
	80	static 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
c72dfae2 SB	88	/* Allocate new CAIF device. */
	89	static 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;
bd30ce4b	93
c72dfae2 SB	94	caifdevs = caif_device_list(dev_net(dev));
c72dfae2 SB	95	BUG_ON(!caifdevs);
bd30ce4b	96
4fb66b82	97	caifd = kzalloc(sizeof(*caifd), GFP_KERNEL);
c72dfae2 SB	98	if (!caifd)
c72dfae2 SB	99	return NULL;
bd30ce4b	100	caifd->pcpu_refcnt = alloc_percpu(int);
4fb66b82 ED	101	if (!caifd->pcpu_refcnt) {
	102	kfree(caifd);
	103	return NULL;
	104	}
c72dfae2	105	caifd->netdev = dev;
bd30ce4b	106	dev_hold(dev);
c72dfae2 SB	107	return caifd;
	108	}
	109
	110	static 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);
bd30ce4b	116	list_for_each_entry_rcu(caifd, &caifdevs->list, list) {
c72dfae2 SB	117	if (caifd->netdev == dev)
	118	return caifd;
	119	}
	120	return NULL;
	121	}
	122
c72dfae2 SB	123	static int transmit(struct cflayer layer, struct cfpkt pkt)
c72dfae2 SB	124	{
c85c2951	125	int err;
c72dfae2 SB	126	struct caif_device_entry *caifd =
c72dfae2 SB	127	container_of(layer, struct caif_device_entry, layer);
4dd820c0 SB	128	struct sk_buff *skb;
4dd820c0 SB	129
c72dfae2 SB	130	skb = cfpkt_tonative(pkt);
c72dfae2 SB	131	skb->dev = caifd->netdev;
4dd820c0	132
c85c2951	133	err = dev_queue_xmit(skb);
	134	if (err > 0)
	135	err = -EIO;
c72dfae2	136
c85c2951	137	return err;
c72dfae2 SB	138	}
c72dfae2 SB	139
c72dfae2	140	/*
bd30ce4b	141	* Stuff received packets into the CAIF stack.
c72dfae2 SB	142	* On error, returns non-zero and releases the skb.
	143	*/
	144	static int receive(struct sk_buff skb, struct net_device dev,
	145	struct packet_type pkttype, struct net_device orig_dev)
	146	{
c72dfae2 SB	147	struct cfpkt *pkt;
c72dfae2 SB	148	struct caif_device_entry *caifd;
69c867c9	149	int err;
bd30ce4b	150
c72dfae2	151	pkt = cfpkt_fromnative(CAIF_DIR_IN, skb);
bd30ce4b	152
bd30ce4b	153	rcu_read_lock();
c72dfae2	154	caifd = caif_get(dev);
c72dfae2	155
bd30ce4b	156	if (!caifd \|\| !caifd->layer.up \|\| !caifd->layer.up->receive \|\|
	157	!netif_oper_up(caifd->netdev)) {
	158	rcu_read_unlock();
	159	kfree_skb(skb);
c72dfae2	160	return NET_RX_DROP;
bd30ce4b	161	}
	162
	163	/* Hold reference to netdevice while using CAIF stack */
	164	caifd_hold(caifd);
	165	rcu_read_unlock();
c72dfae2	166
69c867c9	167	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);
bd30ce4b	172
	173	/* Release reference to stack upwards */
	174	caifd_put(caifd);
c72dfae2 SB	175	return 0;
	176	}
	177
	178	static struct packet_type caif_packet_type __read_mostly = {
	179	.type = cpu_to_be16(ETH_P_CAIF),
	180	.func = receive,
	181	};
	182
	183	static void dev_flowctrl(struct net_device *dev, int on)
	184	{
bd30ce4b	185	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();
c72dfae2	192	return;
bd30ce4b	193	}
	194
	195	caifd_hold(caifd);
	196	rcu_read_unlock();
c72dfae2 SB	197
	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);
bd30ce4b	203	caifd_put(caifd);
c72dfae2 SB	204	}
	205
	206	/* notify Caif of device events */
	207	static 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;
c72dfae2	214	enum cfcnfg_phy_type phy_type;
bee925db	215	struct cfcnfg *cfg;
08613e46	216	struct caif_device_entry_list *caifdevs;
c72dfae2 SB	217
	218	if (dev->type != ARPHRD_CAIF)
	219	return 0;
	220
bee925db	221	cfg = get_cfcnfg(dev_net(dev));
	222	if (cfg == NULL)
	223	return 0;
	224
08613e46 DW	225	caifdevs = caif_device_list(dev_net(dev));
08613e46 DW	226
c72dfae2 SB	227	switch (what) {
c72dfae2 SB	228	case NETDEV_REGISTER:
c72dfae2	229	caifd = caif_device_alloc(dev);
bd30ce4b	230	if (!caifd)
	231	return 0;
	232
c72dfae2 SB	233	caifdev = netdev_priv(dev);
c72dfae2 SB	234	caifdev->flowctrl = dev_flowctrl;
c72dfae2	235
c72dfae2	236	caifd->layer.transmit = transmit;
c72dfae2 SB	237
	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:
2c485209	245	pref = CFPHYPREF_HIGH_BW;
c72dfae2 SB	246	break;
c72dfae2 SB	247	case CAIF_LINK_LOW_LATENCY:
2c485209	248	pref = CFPHYPREF_LOW_LAT;
c72dfae2 SB	249	break;
	250	default:
	251	pref = CFPHYPREF_HIGH_BW;
	252	break;
	253	}
bd30ce4b	254	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
73d6ac63	261	cfcnfg_add_phy_layer(cfg,
c72dfae2 SB	262	phy_type,
	263	dev,
	264	&caifd->layer,
c72dfae2 SB	265	pref,
	266	caifdev->use_fcs,
	267	caifdev->use_stx);
bd30ce4b	268	mutex_unlock(&caifdevs->lock);
c72dfae2 SB	269	break;
c72dfae2 SB	270
bd30ce4b	271	case NETDEV_UP:
	272	rcu_read_lock();
	273
c72dfae2	274	caifd = caif_get(dev);
bd30ce4b	275	if (caifd == NULL) {
bd30ce4b	276	rcu_read_unlock();
c72dfae2	277	break;
bd30ce4b	278	}
c72dfae2	279
bd30ce4b	280	cfcnfg_set_phy_state(cfg, &caifd->layer, true);
bd30ce4b	281	rcu_read_unlock();
c72dfae2	282
c72dfae2 SB	283	break;
	284
	285	case NETDEV_DOWN:
bd30ce4b	286	rcu_read_lock();
bd30ce4b	287
c72dfae2	288	caifd = caif_get(dev);
bd30ce4b	289	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);
c72dfae2 SB	302	break;
	303
	304	case NETDEV_UNREGISTER:
bd30ce4b	305	mutex_lock(&caifdevs->lock);
bd30ce4b	306
c72dfae2	307	caifd = caif_get(dev);
bd30ce4b	308	if (caifd == NULL) {
bd30ce4b	309	mutex_unlock(&caifdevs->lock);
f2527ec4	310	break;
bd30ce4b	311	}
	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);
c72dfae2 SB	342	break;
	343	}
	344	return 0;
	345	}
	346
	347	static struct notifier_block caif_device_notifier = {
	348	.notifier_call = caif_device_notify,
	349	.priority = 0,
	350	};
	351
c72dfae2 SB	352	/* Per-namespace Caif devices handling */
	353	static int caif_init_net(struct net *net)
	354	{
	355	struct caif_net *caifn = net_generic(net, caif_net_id);
bee925db	356	BUG_ON(!caifn);
c72dfae2	357	INIT_LIST_HEAD(&caifn->caifdevs.list);
bd30ce4b	358	mutex_init(&caifn->caifdevs.lock);
bee925db	359
	360	caifn->cfg = cfcnfg_create();
	361	if (!caifn->cfg) {
	362	pr_warn("can't create cfcnfg\n");
	363	return -ENOMEM;
	364	}
	365
c72dfae2 SB	366	return 0;
	367	}
	368
	369	static void caif_exit_net(struct net *net)
	370	{
bd30ce4b	371	struct caif_device_entry caifd, tmp;
	372	struct caif_device_entry_list *caifdevs =
	373	caif_device_list(net);
bee925db	374	struct cfcnfg *cfg;
bd30ce4b	375
c72dfae2	376	rtnl_lock();
bd30ce4b	377	mutex_lock(&caifdevs->lock);
bd30ce4b	378
bee925db	379	cfg = get_cfcnfg(net);
	380	if (cfg == NULL) {
	381	mutex_unlock(&caifdevs->lock);
	382	return;
	383	}
	384
bd30ce4b	385	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);
c72dfae2	402	}
bee925db	403	cfcnfg_remove(cfg);
bd30ce4b	404
bd30ce4b	405	mutex_unlock(&caifdevs->lock);
c72dfae2 SB	406	rtnl_unlock();
	407	}
	408
	409	static 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 */
	417	static int __init caif_device_init(void)
	418	{
	419	int result;
bd30ce4b	420
c72dfae2 SB	421	result = register_pernet_device(&caif_net_ops);
c72dfae2 SB	422
bee925db	423	if (result)
c72dfae2	424	return result;
bee925db	425
c72dfae2	426	register_netdevice_notifier(&caif_device_notifier);
bee925db	427	dev_add_pack(&caif_packet_type);
c72dfae2 SB	428
c72dfae2 SB	429	return result;
c72dfae2 SB	430	}
	431
	432	static void __exit caif_device_exit(void)
	433	{
c72dfae2 SB	434	unregister_pernet_device(&caif_net_ops);
c72dfae2 SB	435	unregister_netdevice_notifier(&caif_device_notifier);
bee925db	436	dev_remove_pack(&caif_packet_type);
c72dfae2 SB	437	}
	438
	439	module_init(caif_device_init);
	440	module_exit(caif_device_exit);