[linux-block.git] / net / caif / chnl_net.c

/*
 * Copyright (C) ST-Ericsson AB 2010
 * Authors:	Sjur Brendeland/sjur.brandeland@stericsson.com
 *		Daniel Martensson / Daniel.Martensson@stericsson.com
 * License terms: GNU General Public License (GPL) version 2
 */

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

#include <linux/fs.h>
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/moduleparam.h>
#include <linux/ip.h>
#include <linux/sched.h>
#include <linux/sockios.h>
#include <linux/caif/if_caif.h>
#include <net/rtnetlink.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfpkt.h>
#include <net/caif/caif_dev.h>

/* GPRS PDP connection has MTU to 1500 */
#define GPRS_PDP_MTU 1500
/* 5 sec. connect timeout */
#define CONNECT_TIMEOUT (5 * HZ)
#define CAIF_NET_DEFAULT_QUEUE_LEN 500
#define UNDEF_CONNID 0xffffffff

/*This list is protected by the rtnl lock. */
static LIST_HEAD(chnl_net_list);

MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("caif");

enum caif_states {
	CAIF_CONNECTED		= 1,
	CAIF_CONNECTING,
	CAIF_DISCONNECTED,
	CAIF_SHUTDOWN
};

struct chnl_net {
	struct cflayer chnl;
	struct net_device_stats stats;
	struct caif_connect_request conn_req;
	struct list_head list_field;
	struct net_device *netdev;
	char name[256];
	wait_queue_head_t netmgmt_wq;
	/* Flow status to remember and control the transmission. */
	bool flowenabled;
	enum caif_states state;
};

static void robust_list_del(struct list_head *delete_node)
{
	struct list_head *list_node;
	struct list_head *n;
	ASSERT_RTNL();
	list_for_each_safe(list_node, n, &chnl_net_list) {
		if (list_node == delete_node) {
			list_del(list_node);
			return;
		}
	}
	WARN_ON(1);
}

static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
{
	struct sk_buff *skb;
	struct chnl_net *priv;
	int pktlen;
	const u8 *ip_version;
	u8 buf;

	priv = container_of(layr, struct chnl_net, chnl);
	if (!priv)
		return -EINVAL;

	skb = (struct sk_buff *) cfpkt_tonative(pkt);

	/* Get length of CAIF packet. */
	pktlen = skb->len;

	/* Pass some minimum information and
	 * send the packet to the net stack.
	 */
	skb->dev = priv->netdev;

	/* check the version of IP */
	ip_version = skb_header_pointer(skb, 0, 1, &buf);

	switch (*ip_version >> 4) {
	case 4:
		skb->protocol = htons(ETH_P_IP);
		break;
	case 6:
		skb->protocol = htons(ETH_P_IPV6);
		break;
	default:
		priv->netdev->stats.rx_errors++;
		return -EINVAL;
	}

	/* If we change the header in loop mode, the checksum is corrupted. */
	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
		skb->ip_summed = CHECKSUM_UNNECESSARY;
	else
		skb->ip_summed = CHECKSUM_NONE;

	if (in_interrupt())
		netif_rx(skb);
	else
		netif_rx_ni(skb);

	/* Update statistics. */
	priv->netdev->stats.rx_packets++;
	priv->netdev->stats.rx_bytes += pktlen;

	return 0;
}

static int delete_device(struct chnl_net *dev)
{
	ASSERT_RTNL();
	if (dev->netdev)
		unregister_netdevice(dev->netdev);
	return 0;
}

static void close_work(struct work_struct *work)
{
	struct chnl_net *dev = NULL;
	struct list_head *list_node;
	struct list_head *_tmp;

	rtnl_lock();
	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
		dev = list_entry(list_node, struct chnl_net, list_field);
		if (dev->state == CAIF_SHUTDOWN)
			dev_close(dev->netdev);
	}
	rtnl_unlock();
}
static DECLARE_WORK(close_worker, close_work);

static void chnl_hold(struct cflayer *lyr)
{
	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
	dev_hold(priv->netdev);
}

static void chnl_put(struct cflayer *lyr)
{
	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
	dev_put(priv->netdev);
}

static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
				int phyid)
{
	struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
	pr_debug("NET flowctrl func called flow: %s\n",
		flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
		flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
		flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
		flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
		flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
		flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
		 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");


	switch (flow) {
	case CAIF_CTRLCMD_FLOW_OFF_IND:
		priv->flowenabled = false;
		netif_stop_queue(priv->netdev);
		break;
	case CAIF_CTRLCMD_DEINIT_RSP:
		priv->state = CAIF_DISCONNECTED;
		break;
	case CAIF_CTRLCMD_INIT_FAIL_RSP:
		priv->state = CAIF_DISCONNECTED;
		wake_up_interruptible(&priv->netmgmt_wq);
		break;
	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
		priv->state = CAIF_SHUTDOWN;
		netif_tx_disable(priv->netdev);
		schedule_work(&close_worker);
		break;
	case CAIF_CTRLCMD_FLOW_ON_IND:
		priv->flowenabled = true;
		netif_wake_queue(priv->netdev);
		break;
	case CAIF_CTRLCMD_INIT_RSP:
		caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
		priv->state = CAIF_CONNECTED;
		priv->flowenabled = true;
		netif_wake_queue(priv->netdev);
		wake_up_interruptible(&priv->netmgmt_wq);
		break;
	default:
		break;
	}
}

static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct chnl_net *priv;
	struct cfpkt *pkt = NULL;
	int len;
	int result = -1;
	/* Get our private data. */
	priv = netdev_priv(dev);

	if (skb->len > priv->netdev->mtu) {
		pr_warn("Size of skb exceeded MTU\n");
		dev->stats.tx_errors++;
		return -ENOSPC;
	}

	if (!priv->flowenabled) {
		pr_debug("dropping packets flow off\n");
		dev->stats.tx_dropped++;
		return NETDEV_TX_BUSY;
	}

	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
		swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);

	/* Store original SKB length. */
	len = skb->len;

	pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);

	/* Send the packet down the stack. */
	result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
	if (result) {
		dev->stats.tx_dropped++;
		return result;
	}

	/* Update statistics. */
	dev->stats.tx_packets++;
	dev->stats.tx_bytes += len;

	return NETDEV_TX_OK;
}

static int chnl_net_open(struct net_device *dev)
{
	struct chnl_net *priv = NULL;
	int result = -1;
	int llifindex, headroom, tailroom, mtu;
	struct net_device *lldev;
	ASSERT_RTNL();
	priv = netdev_priv(dev);
	if (!priv) {
		pr_debug("chnl_net_open: no priv\n");
		return -ENODEV;
	}

	if (priv->state != CAIF_CONNECTING) {
		priv->state = CAIF_CONNECTING;
		result = caif_connect_client(dev_net(dev), &priv->conn_req,
						&priv->chnl, &llifindex,
						&headroom, &tailroom);
		if (result != 0) {
				pr_debug("err: "
					 "Unable to register and open device,"
					 " Err:%d\n",
					 result);
				goto error;
		}

		lldev = dev_get_by_index(dev_net(dev), llifindex);

		if (lldev == NULL) {
			pr_debug("no interface?\n");
			result = -ENODEV;
			goto error;
		}

		dev->needed_tailroom = tailroom + lldev->needed_tailroom;
		dev->hard_header_len = headroom + lldev->hard_header_len +
			lldev->needed_tailroom;

		/*
		 * MTU, head-room etc is not know before we have a
		 * CAIF link layer device available. MTU calculation may
		 * override initial RTNL configuration.
		 * MTU is minimum of current mtu, link layer mtu pluss
		 * CAIF head and tail, and PDP GPRS contexts max MTU.
		 */
		mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
		mtu = min_t(int, GPRS_PDP_MTU, mtu);
		dev_set_mtu(dev, mtu);
		dev_put(lldev);

		if (mtu < 100) {
			pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
			result = -ENODEV;
			goto error;
		}
	}

	rtnl_unlock();  /* Release RTNL lock during connect wait */

	result = wait_event_interruptible_timeout(priv->netmgmt_wq,
						priv->state != CAIF_CONNECTING,
						CONNECT_TIMEOUT);

	rtnl_lock();

	if (result == -ERESTARTSYS) {
		pr_debug("wait_event_interruptible woken by a signal\n");
		result = -ERESTARTSYS;
		goto error;
	}

	if (result == 0) {
		pr_debug("connect timeout\n");
		caif_disconnect_client(dev_net(dev), &priv->chnl);
		priv->state = CAIF_DISCONNECTED;
		pr_debug("state disconnected\n");
		result = -ETIMEDOUT;
		goto error;
	}

	if (priv->state != CAIF_CONNECTED) {
		pr_debug("connect failed\n");
		result = -ECONNREFUSED;
		goto error;
	}
	pr_debug("CAIF Netdevice connected\n");
	return 0;

error:
	caif_disconnect_client(dev_net(dev), &priv->chnl);
	priv->state = CAIF_DISCONNECTED;
	pr_debug("state disconnected\n");
	return result;

}

static int chnl_net_stop(struct net_device *dev)
{
	struct chnl_net *priv;

	ASSERT_RTNL();
	priv = netdev_priv(dev);
	priv->state = CAIF_DISCONNECTED;
	caif_disconnect_client(dev_net(dev), &priv->chnl);
	return 0;
}

static int chnl_net_init(struct net_device *dev)
{
	struct chnl_net *priv;
	ASSERT_RTNL();
	priv = netdev_priv(dev);
	strncpy(priv->name, dev->name, sizeof(priv->name));
	return 0;
}

static void chnl_net_uninit(struct net_device *dev)
{
	struct chnl_net *priv;
	ASSERT_RTNL();
	priv = netdev_priv(dev);
	robust_list_del(&priv->list_field);
}

static const struct net_device_ops netdev_ops = {
	.ndo_open = chnl_net_open,
	.ndo_stop = chnl_net_stop,
	.ndo_init = chnl_net_init,
	.ndo_uninit = chnl_net_uninit,
	.ndo_start_xmit = chnl_net_start_xmit,
};

static void chnl_net_destructor(struct net_device *dev)
{
	struct chnl_net *priv = netdev_priv(dev);
	caif_free_client(&priv->chnl);
	free_netdev(dev);
}

static void ipcaif_net_setup(struct net_device *dev)
{
	struct chnl_net *priv;
	dev->netdev_ops = &netdev_ops;
	dev->destructor = chnl_net_destructor;
	dev->flags |= IFF_NOARP;
	dev->flags |= IFF_POINTOPOINT;
	dev->mtu = GPRS_PDP_MTU;
	dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;

	priv = netdev_priv(dev);
	priv->chnl.receive = chnl_recv_cb;
	priv->chnl.ctrlcmd = chnl_flowctrl_cb;
	priv->netdev = dev;
	priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
	priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
	priv->conn_req.priority = CAIF_PRIO_LOW;
	/* Insert illegal value */
	priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
	priv->flowenabled = false;

	init_waitqueue_head(&priv->netmgmt_wq);
}


static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
	struct chnl_net *priv;
	u8 loop;
	priv = netdev_priv(dev);
	NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID,
		    priv->conn_req.sockaddr.u.dgm.connection_id);
	NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID,
		    priv->conn_req.sockaddr.u.dgm.connection_id);
	loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
	NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);


	return 0;
nla_put_failure:
	return -EMSGSIZE;

}

static void caif_netlink_parms(struct nlattr *data[],
				struct caif_connect_request *conn_req)
{
	if (!data) {
		pr_warn("no params data found\n");
		return;
	}
	if (data[IFLA_CAIF_IPV4_CONNID])
		conn_req->sockaddr.u.dgm.connection_id =
			nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
	if (data[IFLA_CAIF_IPV6_CONNID])
		conn_req->sockaddr.u.dgm.connection_id =
			nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
	if (data[IFLA_CAIF_LOOPBACK]) {
		if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
			conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
		else
			conn_req->protocol = CAIFPROTO_DATAGRAM;
	}
}

static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
			  struct nlattr *tb[], struct nlattr *data[])
{
	int ret;
	struct chnl_net *caifdev;
	ASSERT_RTNL();
	caifdev = netdev_priv(dev);
	caif_netlink_parms(data, &caifdev->conn_req);
	dev_net_set(caifdev->netdev, src_net);

	ret = register_netdevice(dev);
	if (ret)
		pr_warn("device rtml registration failed\n");
	else
		list_add(&caifdev->list_field, &chnl_net_list);

	/* Use ifindex as connection id, and use loopback channel default. */
	if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
		caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
		caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
	}
	return ret;
}

static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
				struct nlattr *data[])
{
	struct chnl_net *caifdev;
	ASSERT_RTNL();
	caifdev = netdev_priv(dev);
	caif_netlink_parms(data, &caifdev->conn_req);
	netdev_state_change(dev);
	return 0;
}

static size_t ipcaif_get_size(const struct net_device *dev)
{
	return
		/* IFLA_CAIF_IPV4_CONNID */
		nla_total_size(4) +
		/* IFLA_CAIF_IPV6_CONNID */
		nla_total_size(4) +
		/* IFLA_CAIF_LOOPBACK */
		nla_total_size(2) +
		0;
}

static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
	[IFLA_CAIF_IPV4_CONNID]	      = { .type = NLA_U32 },
	[IFLA_CAIF_IPV6_CONNID]	      = { .type = NLA_U32 },
	[IFLA_CAIF_LOOPBACK]	      = { .type = NLA_U8 }
};


static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
	.kind		= "caif",
	.priv_size	= sizeof(struct chnl_net),
	.setup		= ipcaif_net_setup,
	.maxtype	= IFLA_CAIF_MAX,
	.policy		= ipcaif_policy,
	.newlink	= ipcaif_newlink,
	.changelink	= ipcaif_changelink,
	.get_size	= ipcaif_get_size,
	.fill_info	= ipcaif_fill_info,

};

static int __init chnl_init_module(void)
{
	return rtnl_link_register(&ipcaif_link_ops);
}

static void __exit chnl_exit_module(void)
{
	struct chnl_net *dev = NULL;
	struct list_head *list_node;
	struct list_head *_tmp;
	rtnl_link_unregister(&ipcaif_link_ops);
	rtnl_lock();
	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
		dev = list_entry(list_node, struct chnl_net, list_field);
		list_del(list_node);
		delete_device(dev);
	}
	rtnl_unlock();
}

module_init(chnl_init_module);
module_exit(chnl_exit_module);
Commit	Line	Data
	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	#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
	9
	10	#include <linux/fs.h>
	11	#include <linux/hardirq.h>
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/netdevice.h>
	15	#include <linux/if_ether.h>
	16	#include <linux/moduleparam.h>
	17	#include <linux/ip.h>
	18	#include <linux/sched.h>
	19	#include <linux/sockios.h>
	20	#include <linux/caif/if_caif.h>
	21	#include <net/rtnetlink.h>
	22	#include <net/caif/caif_layer.h>
	23	#include <net/caif/cfpkt.h>
	24	#include <net/caif/caif_dev.h>
	25
	26	/* GPRS PDP connection has MTU to 1500 */
	27	#define GPRS_PDP_MTU 1500
	28	/* 5 sec. connect timeout */
	29	#define CONNECT_TIMEOUT (5 * HZ)
	30	#define CAIF_NET_DEFAULT_QUEUE_LEN 500
	31	#define UNDEF_CONNID 0xffffffff
	32
	33	/This list is protected by the rtnl lock. /
	34	static LIST_HEAD(chnl_net_list);
	35
	36	MODULE_LICENSE("GPL");
	37	MODULE_ALIAS_RTNL_LINK("caif");
	38
	39	enum caif_states {
	40	CAIF_CONNECTED = 1,
	41	CAIF_CONNECTING,
	42	CAIF_DISCONNECTED,
	43	CAIF_SHUTDOWN
	44	};
	45
	46	struct chnl_net {
	47	struct cflayer chnl;
	48	struct net_device_stats stats;
	49	struct caif_connect_request conn_req;
	50	struct list_head list_field;
	51	struct net_device *netdev;
	52	char name[256];
	53	wait_queue_head_t netmgmt_wq;
	54	/* Flow status to remember and control the transmission. */
	55	bool flowenabled;
	56	enum caif_states state;
	57	};
	58
	59	static void robust_list_del(struct list_head *delete_node)
	60	{
	61	struct list_head *list_node;
	62	struct list_head *n;
	63	ASSERT_RTNL();
	64	list_for_each_safe(list_node, n, &chnl_net_list) {
	65	if (list_node == delete_node) {
	66	list_del(list_node);
	67	return;
	68	}
	69	}
	70	WARN_ON(1);
	71	}
	72
	73	static int chnl_recv_cb(struct cflayer layr, struct cfpkt pkt)
	74	{
	75	struct sk_buff *skb;
	76	struct chnl_net *priv;
	77	int pktlen;
	78	const u8 *ip_version;
	79	u8 buf;
	80
	81	priv = container_of(layr, struct chnl_net, chnl);
	82	if (!priv)
	83	return -EINVAL;
	84
	85	skb = (struct sk_buff *) cfpkt_tonative(pkt);
	86
	87	/* Get length of CAIF packet. */
	88	pktlen = skb->len;
	89
	90	/* Pass some minimum information and
	91	* send the packet to the net stack.
	92	*/
	93	skb->dev = priv->netdev;
	94
	95	/* check the version of IP */
	96	ip_version = skb_header_pointer(skb, 0, 1, &buf);
	97
	98	switch (*ip_version >> 4) {
	99	case 4:
	100	skb->protocol = htons(ETH_P_IP);
	101	break;
	102	case 6:
	103	skb->protocol = htons(ETH_P_IPV6);
	104	break;
	105	default:
	106	priv->netdev->stats.rx_errors++;
	107	return -EINVAL;
	108	}
	109
	110	/* If we change the header in loop mode, the checksum is corrupted. */
	111	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
	112	skb->ip_summed = CHECKSUM_UNNECESSARY;
	113	else
	114	skb->ip_summed = CHECKSUM_NONE;
	115
	116	if (in_interrupt())
	117	netif_rx(skb);
	118	else
	119	netif_rx_ni(skb);
	120
	121	/* Update statistics. */
	122	priv->netdev->stats.rx_packets++;
	123	priv->netdev->stats.rx_bytes += pktlen;
	124
	125	return 0;
	126	}
	127
	128	static int delete_device(struct chnl_net *dev)
	129	{
	130	ASSERT_RTNL();
	131	if (dev->netdev)
	132	unregister_netdevice(dev->netdev);
	133	return 0;
	134	}
	135
	136	static void close_work(struct work_struct *work)
	137	{
	138	struct chnl_net *dev = NULL;
	139	struct list_head *list_node;
	140	struct list_head *_tmp;
	141
	142	rtnl_lock();
	143	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
	144	dev = list_entry(list_node, struct chnl_net, list_field);
	145	if (dev->state == CAIF_SHUTDOWN)
	146	dev_close(dev->netdev);
	147	}
	148	rtnl_unlock();
	149	}
	150	static DECLARE_WORK(close_worker, close_work);
	151
	152	static void chnl_hold(struct cflayer *lyr)
	153	{
	154	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
	155	dev_hold(priv->netdev);
	156	}
	157
	158	static void chnl_put(struct cflayer *lyr)
	159	{
	160	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
	161	dev_put(priv->netdev);
	162	}
	163
	164	static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
	165	int phyid)
	166	{
	167	struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
	168	pr_debug("NET flowctrl func called flow: %s\n",
	169	flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
	170	flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
	171	flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
	172	flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
	173	flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
	174	flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
	175	"REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
	176
	177
	178
	179	switch (flow) {
	180	case CAIF_CTRLCMD_FLOW_OFF_IND:
	181	priv->flowenabled = false;
	182	netif_stop_queue(priv->netdev);
	183	break;
	184	case CAIF_CTRLCMD_DEINIT_RSP:
	185	priv->state = CAIF_DISCONNECTED;
	186	break;
	187	case CAIF_CTRLCMD_INIT_FAIL_RSP:
	188	priv->state = CAIF_DISCONNECTED;
	189	wake_up_interruptible(&priv->netmgmt_wq);
	190	break;
	191	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
	192	priv->state = CAIF_SHUTDOWN;
	193	netif_tx_disable(priv->netdev);
	194	schedule_work(&close_worker);
	195	break;
	196	case CAIF_CTRLCMD_FLOW_ON_IND:
	197	priv->flowenabled = true;
	198	netif_wake_queue(priv->netdev);
	199	break;
	200	case CAIF_CTRLCMD_INIT_RSP:
	201	caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
	202	priv->state = CAIF_CONNECTED;
	203	priv->flowenabled = true;
	204	netif_wake_queue(priv->netdev);
	205	wake_up_interruptible(&priv->netmgmt_wq);
	206	break;
	207	default:
	208	break;
	209	}
	210	}
	211
	212	static int chnl_net_start_xmit(struct sk_buff skb, struct net_device dev)
	213	{
	214	struct chnl_net *priv;
	215	struct cfpkt *pkt = NULL;
	216	int len;
	217	int result = -1;
	218	/* Get our private data. */
	219	priv = netdev_priv(dev);
	220
	221	if (skb->len > priv->netdev->mtu) {
	222	pr_warn("Size of skb exceeded MTU\n");
	223	dev->stats.tx_errors++;
	224	return -ENOSPC;
	225	}
	226
	227	if (!priv->flowenabled) {
	228	pr_debug("dropping packets flow off\n");
	229	dev->stats.tx_dropped++;
	230	return NETDEV_TX_BUSY;
	231	}
	232
	233	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
	234	swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
	235
	236	/* Store original SKB length. */
	237	len = skb->len;
	238
	239	pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
	240
	241	/* Send the packet down the stack. */
	242	result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
	243	if (result) {
	244	dev->stats.tx_dropped++;
	245	return result;
	246	}
	247
	248	/* Update statistics. */
	249	dev->stats.tx_packets++;
	250	dev->stats.tx_bytes += len;
	251
	252	return NETDEV_TX_OK;
	253	}
	254
	255	static int chnl_net_open(struct net_device *dev)
	256	{
	257	struct chnl_net *priv = NULL;
	258	int result = -1;
	259	int llifindex, headroom, tailroom, mtu;
	260	struct net_device *lldev;
	261	ASSERT_RTNL();
	262	priv = netdev_priv(dev);
	263	if (!priv) {
	264	pr_debug("chnl_net_open: no priv\n");
	265	return -ENODEV;
	266	}
	267
	268	if (priv->state != CAIF_CONNECTING) {
	269	priv->state = CAIF_CONNECTING;
	270	result = caif_connect_client(dev_net(dev), &priv->conn_req,
	271	&priv->chnl, &llifindex,
	272	&headroom, &tailroom);
	273	if (result != 0) {
	274	pr_debug("err: "
	275	"Unable to register and open device,"
	276	" Err:%d\n",
	277	result);
	278	goto error;
	279	}
	280
	281	lldev = dev_get_by_index(dev_net(dev), llifindex);
	282
	283	if (lldev == NULL) {
	284	pr_debug("no interface?\n");
	285	result = -ENODEV;
	286	goto error;
	287	}
	288
	289	dev->needed_tailroom = tailroom + lldev->needed_tailroom;
	290	dev->hard_header_len = headroom + lldev->hard_header_len +
	291	lldev->needed_tailroom;
	292
	293	/*
	294	* MTU, head-room etc is not know before we have a
	295	* CAIF link layer device available. MTU calculation may
	296	* override initial RTNL configuration.
	297	* MTU is minimum of current mtu, link layer mtu pluss
	298	* CAIF head and tail, and PDP GPRS contexts max MTU.
	299	*/
	300	mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
	301	mtu = min_t(int, GPRS_PDP_MTU, mtu);
	302	dev_set_mtu(dev, mtu);
	303	dev_put(lldev);
	304
	305	if (mtu < 100) {
	306	pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
	307	result = -ENODEV;
	308	goto error;
	309	}
	310	}
	311
	312	rtnl_unlock(); /* Release RTNL lock during connect wait */
	313
	314	result = wait_event_interruptible_timeout(priv->netmgmt_wq,
	315	priv->state != CAIF_CONNECTING,
	316	CONNECT_TIMEOUT);
	317
	318	rtnl_lock();
	319
	320	if (result == -ERESTARTSYS) {
	321	pr_debug("wait_event_interruptible woken by a signal\n");
	322	result = -ERESTARTSYS;
	323	goto error;
	324	}
	325
	326	if (result == 0) {
	327	pr_debug("connect timeout\n");
	328	caif_disconnect_client(dev_net(dev), &priv->chnl);
	329	priv->state = CAIF_DISCONNECTED;
	330	pr_debug("state disconnected\n");
	331	result = -ETIMEDOUT;
	332	goto error;
	333	}
	334
	335	if (priv->state != CAIF_CONNECTED) {
	336	pr_debug("connect failed\n");
	337	result = -ECONNREFUSED;
	338	goto error;
	339	}
	340	pr_debug("CAIF Netdevice connected\n");
	341	return 0;
	342
	343	error:
	344	caif_disconnect_client(dev_net(dev), &priv->chnl);
	345	priv->state = CAIF_DISCONNECTED;
	346	pr_debug("state disconnected\n");
	347	return result;
	348
	349	}
	350
	351	static int chnl_net_stop(struct net_device *dev)
	352	{
	353	struct chnl_net *priv;
	354
	355	ASSERT_RTNL();
	356	priv = netdev_priv(dev);
	357	priv->state = CAIF_DISCONNECTED;
	358	caif_disconnect_client(dev_net(dev), &priv->chnl);
	359	return 0;
	360	}
	361
	362	static int chnl_net_init(struct net_device *dev)
	363	{
	364	struct chnl_net *priv;
	365	ASSERT_RTNL();
	366	priv = netdev_priv(dev);
	367	strncpy(priv->name, dev->name, sizeof(priv->name));
	368	return 0;
	369	}
	370
	371	static void chnl_net_uninit(struct net_device *dev)
	372	{
	373	struct chnl_net *priv;
	374	ASSERT_RTNL();
	375	priv = netdev_priv(dev);
	376	robust_list_del(&priv->list_field);
	377	}
	378
	379	static const struct net_device_ops netdev_ops = {
	380	.ndo_open = chnl_net_open,
	381	.ndo_stop = chnl_net_stop,
	382	.ndo_init = chnl_net_init,
	383	.ndo_uninit = chnl_net_uninit,
	384	.ndo_start_xmit = chnl_net_start_xmit,
	385	};
	386
	387	static void chnl_net_destructor(struct net_device *dev)
	388	{
	389	struct chnl_net *priv = netdev_priv(dev);
	390	caif_free_client(&priv->chnl);
	391	free_netdev(dev);
	392	}
	393
	394	static void ipcaif_net_setup(struct net_device *dev)
	395	{
	396	struct chnl_net *priv;
	397	dev->netdev_ops = &netdev_ops;
	398	dev->destructor = chnl_net_destructor;
	399	dev->flags \|= IFF_NOARP;
	400	dev->flags \|= IFF_POINTOPOINT;
	401	dev->mtu = GPRS_PDP_MTU;
	402	dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
	403
	404	priv = netdev_priv(dev);
	405	priv->chnl.receive = chnl_recv_cb;
	406	priv->chnl.ctrlcmd = chnl_flowctrl_cb;
	407	priv->netdev = dev;
	408	priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
	409	priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
	410	priv->conn_req.priority = CAIF_PRIO_LOW;
	411	/* Insert illegal value */
	412	priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
	413	priv->flowenabled = false;
	414
	415	init_waitqueue_head(&priv->netmgmt_wq);
	416	}
	417
	418
	419	static int ipcaif_fill_info(struct sk_buff skb, const struct net_device dev)
	420	{
	421	struct chnl_net *priv;
	422	u8 loop;
	423	priv = netdev_priv(dev);
	424	NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID,
	425	priv->conn_req.sockaddr.u.dgm.connection_id);
	426	NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID,
	427	priv->conn_req.sockaddr.u.dgm.connection_id);
	428	loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
	429	NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);
	430
	431
	432	return 0;
	433	nla_put_failure:
	434	return -EMSGSIZE;
	435
	436	}
	437
	438	static void caif_netlink_parms(struct nlattr *data[],
	439	struct caif_connect_request *conn_req)
	440	{
	441	if (!data) {
	442	pr_warn("no params data found\n");
	443	return;
	444	}
	445	if (data[IFLA_CAIF_IPV4_CONNID])
	446	conn_req->sockaddr.u.dgm.connection_id =
	447	nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
	448	if (data[IFLA_CAIF_IPV6_CONNID])
	449	conn_req->sockaddr.u.dgm.connection_id =
	450	nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
	451	if (data[IFLA_CAIF_LOOPBACK]) {
	452	if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
	453	conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
	454	else
	455	conn_req->protocol = CAIFPROTO_DATAGRAM;
	456	}
	457	}
	458
	459	static int ipcaif_newlink(struct net src_net, struct net_device dev,
	460	struct nlattr tb[], struct nlattr data[])
	461	{
	462	int ret;
	463	struct chnl_net *caifdev;
	464	ASSERT_RTNL();
	465	caifdev = netdev_priv(dev);
	466	caif_netlink_parms(data, &caifdev->conn_req);
	467	dev_net_set(caifdev->netdev, src_net);
	468
	469	ret = register_netdevice(dev);
	470	if (ret)
	471	pr_warn("device rtml registration failed\n");
	472	else
	473	list_add(&caifdev->list_field, &chnl_net_list);
	474
	475	/* Use ifindex as connection id, and use loopback channel default. */
	476	if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
	477	caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
	478	caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
	479	}
	480	return ret;
	481	}
	482
	483	static int ipcaif_changelink(struct net_device dev, struct nlattr tb[],
	484	struct nlattr *data[])
	485	{
	486	struct chnl_net *caifdev;
	487	ASSERT_RTNL();
	488	caifdev = netdev_priv(dev);
	489	caif_netlink_parms(data, &caifdev->conn_req);
	490	netdev_state_change(dev);
	491	return 0;
	492	}
	493
	494	static size_t ipcaif_get_size(const struct net_device *dev)
	495	{
	496	return
	497	/* IFLA_CAIF_IPV4_CONNID */
	498	nla_total_size(4) +
	499	/* IFLA_CAIF_IPV6_CONNID */
	500	nla_total_size(4) +
	501	/* IFLA_CAIF_LOOPBACK */
	502	nla_total_size(2) +
	503	0;
	504	}
	505
	506	static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
	507	[IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
	508	[IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
	509	[IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
	510	};
	511
	512
	513	static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
	514	.kind = "caif",
	515	.priv_size = sizeof(struct chnl_net),
	516	.setup = ipcaif_net_setup,
	517	.maxtype = IFLA_CAIF_MAX,
	518	.policy = ipcaif_policy,
	519	.newlink = ipcaif_newlink,
	520	.changelink = ipcaif_changelink,
	521	.get_size = ipcaif_get_size,
	522	.fill_info = ipcaif_fill_info,
	523
	524	};
	525
	526	static int __init chnl_init_module(void)
	527	{
	528	return rtnl_link_register(&ipcaif_link_ops);
	529	}
	530
	531	static void __exit chnl_exit_module(void)
	532	{
	533	struct chnl_net *dev = NULL;
	534	struct list_head *list_node;
	535	struct list_head *_tmp;
	536	rtnl_link_unregister(&ipcaif_link_ops);
	537	rtnl_lock();
	538	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
	539	dev = list_entry(list_node, struct chnl_net, list_field);
	540	list_del(list_node);
	541	delete_device(dev);
	542	}
	543	rtnl_unlock();
	544	}
	545
	546	module_init(chnl_init_module);
	547	module_exit(chnl_exit_module);