drivers/net/brcm_netconsole.c

/*
 *  linux/drivers/net/netconsole.c
 *
 *  Copyright (C) 2001  Ingo Molnar <mingo@redhat.com>
 *
 *  This file contains the implementation of an IRQ-safe, crash-safe
 *  kernel console implementation that outputs kernel messages to the
 *  network.
 *
 * Modification history:
 *
 * 2001-09-17    started by Ingo Molnar.
 * 2003-08-11    2.6 port by Matt Mackall
 *               simplified options
 *               generic card hooks
 *               works non-modular
 * 2003-09-07    rewritten with netpoll api
 */

/****************************************************************
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2, or (at your option)
 *      any later version.
 *
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *
 *      You should have received a copy of the GNU General Public License
 *      along with this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *      Portions of this software are Copyright 2012 Broadcom Corporation
 *
 ****************************************************************/


#include <linux/mm.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/brcm_console.h>
#include <linux/moduleparam.h>
#include <linux/string.h>
#include <linux/netpoll.h>
#include <linux/inet.h>
#include <linux/configfs.h>
#include <linux/net.h>
#include <linux/in.h>

MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
MODULE_DESCRIPTION("Console driver for network interfaces");
MODULE_LICENSE("GPL");

#define MAX_PARAM_LENGTH	256
#define MAX_PRINT_CHUNK	1024

#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif

static char config[MAX_PARAM_LENGTH];
module_param_string(brcm_netconsole, config, MAX_PARAM_LENGTH, 0);
MODULE_PARM_DESC(brcm_netconsole,
		 " brcm_netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]");

#ifndef	MODULE
static int __init option_setup(char *opt)
{
	strlcpy(config, opt, MAX_PARAM_LENGTH);
	return 1;
}

__setup("brcm_netconsole=", option_setup);
#endif /* MODULE */

/* Linked list of all configured targets */
static LIST_HEAD(target_list);

/* This needs to be a spinlock because write_msg() cannot sleep */
static DEFINE_SPINLOCK(target_list_lock);

/**
 * struct brcm_netconsole_target - Represents a configured brcm_netconsole target.
 * @list:	Links this target into the target_list.
 * @item:	Links us into the configfs subsystem hierarchy.
 * @enabled:	On / off knob to enable / disable target.
 *		Visible from userspace (read-write).
 *		We maintain a strict 1:1 correspondence between this and
 *		whether the corresponding netpoll is active or inactive.
 *		Also, other parameters of a target may be modified at
 *		runtime only when it is disabled (enabled == 0).
 * @np:		The netpoll structure for this target.
 *		Contains the other userspace visible parameters:
 *		dev_name	(read-write)
 *		local_port	(read-write)
 *		remote_port	(read-write)
 *		local_ip	(read-write)
 *		remote_ip	(read-write)
 *		local_mac	(read-only)
 *		remote_mac	(read-write)
 */
struct brcm_netconsole_target {
	struct list_head list;
#ifdef	CONFIG_BRCM_NETCONSOLE_DYNAMIC
	struct config_item item;
#endif
	int enabled;
	struct netpoll np;
};

/* global variables */
static bool brcm_netconsole_ready = FALSE, nt_enabled = FALSE;
static unsigned char cur_rndis_status = USB_RNDIS_OFF;

/* external functions */
extern int netpoll_free_memory(void);

static int dummy_start_cb(void)
{
	pr_info("%s\n", __func__);
	brcm_netconsole_ready = TRUE;
	return 0;
}

static int dummy_stop_cb(void)
{
	pr_info("%s\n", __func__);
	brcm_netconsole_ready = FALSE;
	return 0;
}

static struct brcm_netconsole_callbacks brcm_dummy_callbacks = {
	.start = dummy_start_cb,
	.stop = dummy_stop_cb,
};

static struct brcm_netconsole_callbacks *brcm_netconsole_cb =
	&brcm_dummy_callbacks;

#ifdef	CONFIG_BRCM_NETCONSOLE_DYNAMIC

static struct configfs_subsystem brcm_netconsole_subsys;

static int __init dynamic_brcm_netconsole_init(void)
{
	config_group_init(&brcm_netconsole_subsys.su_group);
	mutex_init(&brcm_netconsole_subsys.su_mutex);
	return configfs_register_subsystem(&brcm_netconsole_subsys);
}

static void __exit dynamic_brcm_netconsole_exit(void)
{
	configfs_unregister_subsystem(&brcm_netconsole_subsys);
}

/*
 * Targets that were created by parsing the boot/module option string
 * do not exist in the configfs hierarchy (and have NULL names) and will
 * never go away, so make these a no-op for them.
 */
static void brcm_netconsole_target_get(struct brcm_netconsole_target *nt)
{
	if (config_item_name(&nt->item))
		config_item_get(&nt->item);
}

static void brcm_netconsole_target_put(struct brcm_netconsole_target *nt)
{
	if (config_item_name(&nt->item))
		config_item_put(&nt->item);
}

#else /* !CONFIG_BRCM_NETCONSOLE_DYNAMIC */

static int __init dynamic_brcm_netconsole_init(void)
{
	return 0;
}

static void __exit dynamic_brcm_netconsole_exit(void)
{
}

/*
 * No danger of targets going away from under us when dynamic
 * reconfigurability is off.
 */
static void brcm_netconsole_target_get(struct brcm_netconsole_target *nt)
{
}

static void brcm_netconsole_target_put(struct brcm_netconsole_target *nt)
{
}

#endif /* CONFIG_BRCM_NETCONSOLE_DYNAMIC */

/* Allocate new target (from boot/module param) and setup netpoll for it */
static struct brcm_netconsole_target *alloc_param_target(char *target_config)
{
	int err = -ENOMEM;
	struct brcm_netconsole_target *nt;
	u8 remote_mac[ETH_ALEN];

	/*
	 * Allocate and initialize with defaults.
	 * Note that these targets get their config_item fields zeroed-out.
	 */
	nt = kzalloc(sizeof(*nt), GFP_KERNEL);
	if (!nt) {
		pr_err("brcm_netconsole: failed to allocate memory\n");
		goto fail;
	}

	nt->np.name = "brcm_netconsole";
	strlcpy(nt->np.dev_name, "rndis0", IFNAMSIZ);
	nt->np.local_port = 5042;
	nt->np.remote_port = 5042;
	remote_mac[0] = 0xaa;
	remote_mac[1] = 0xbb;
	remote_mac[2] = 0xcc;
	remote_mac[3] = 0xdd;
	remote_mac[4] = 0xee;
	remote_mac[5] = 0xff;
	memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
	nt->np.remote_ip.ip = in_aton("255.255.255.255");
	nt->np.local_ip.ip = in_aton("192.168.42.129");

	/* Parse parameters and setup netpoll */
#if 0				/* kevin */
	err = netpoll_parse_options(&nt->np, target_config);
	if (err)
		goto fail;
#endif

	err = netpoll_setup(&nt->np);
	if (err)
		goto fail;

	nt->enabled = 1;
	nt_enabled = TRUE;

	return nt;

fail:
	kfree(nt);
	return ERR_PTR(err);
}

/* Cleanup netpoll for given target (from boot/module param) and free it */
static void free_param_target(struct brcm_netconsole_target *nt)
{
	netpoll_cleanup(&nt->np);
	kfree(nt);
}

#ifdef	CONFIG_BRCM_NETCONSOLE_DYNAMIC

/*
 * Our subsystem hierarchy is:
 *
 * /sys/kernel/config/brcm_netconsole/
 *				|
 *				<target>/
 *				|	enabled
 *				|	dev_name
 *				|	local_port
 *				|	remote_port
 *				|	local_ip
 *				|	remote_ip
 *				|	local_mac
 *				|	remote_mac
 *				|
 *				<target>/...
 */

struct brcm_netconsole_target_attr {
	struct configfs_attribute attr;
	ssize_t (*show) (struct brcm_netconsole_target *nt, char *buf);
	ssize_t (*store) (struct brcm_netconsole_target *nt,
			  const char *buf, size_t count);
};

static struct brcm_netconsole_target *to_target(struct config_item *item)
{
	return item ?
	    container_of(item, struct brcm_netconsole_target, item) : NULL;
}

/*
 * Wrapper over simple_strtol (base 10) with sanity and range checking.
 * We return (signed) long only because we may want to return errors.
 * Do not use this to convert numbers that are allowed to be negative.
 */
static long strtol10_check_range(const char *cp, long min, long max)
{
	long ret;
	char *p = (char *)cp;

	WARN_ON(min < 0);
	WARN_ON(max < min);

	ret = simple_strtol(p, &p, 10);

	if (*p && (*p != '\n')) {
		pr_err("brcm_netconsole: invalid input\n");
		return -EINVAL;
	}
	if ((ret < min) || (ret > max)) {
		pr_err("brcm_netconsole: input %ld must be between "
		       "%ld and %ld\n", ret, min, max);
		return -EINVAL;
	}

	return ret;
}

/*
 * Attribute operations for brcm_netconsole_target.
 */

static ssize_t show_enabled(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
}

static ssize_t show_dev_name(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
}

static ssize_t show_local_port(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
}

static ssize_t show_remote_port(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
}

static ssize_t show_local_ip(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
}

static ssize_t show_remote_ip(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
}

static ssize_t show_local_mac(struct brcm_netconsole_target *nt, char *buf)
{
	struct net_device *dev = nt->np.dev;
	static const u8 bcast[ETH_ALEN] = {
		0xff, 0xff, 0xff, 0xff, 0xff, 0xff
	};

	return snprintf(buf, PAGE_SIZE, "%pM\n", dev ? dev->dev_addr : bcast);
}

static ssize_t show_remote_mac(struct brcm_netconsole_target *nt, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%pM\n", nt->np.remote_mac);
}

/*
 * This one is special -- targets created through the configfs interface
 * are not enabled (and the corresponding netpoll activated) by default.
 * The user is expected to set the desired parameters first (which
 * would enable him to dynamically add new netpoll targets for new
 * network interfaces as and when they come up).
 */
static ssize_t store_enabled(struct brcm_netconsole_target *nt,
			     const char *buf, size_t count)
{
	int err;
	long enabled;

	enabled = strtol10_check_range(buf, 0, 1);
	if (enabled < 0)
		return enabled;

	pr_info("%s enabled=%d\n", __func__, (int)enabled);

	if (enabled) {		/* 1 */

		/*
		 * Skip netpoll_parse_options() -- all the attributes are
		 * already configured via configfs. Just print them out.
		 */
		netpoll_print_options(&nt->np);

		err = netpoll_setup(&nt->np);
		if (err)
			return err;

		if (cur_rndis_status && brcm_netconsole_cb->start)
			brcm_netconsole_cb->start();

		nt_enabled = TRUE;
		pr_info("brcm_netconsole: network logging started\n");

	} else {		/* 0 */
		if (brcm_netconsole_cb->stop)
			brcm_netconsole_cb->stop();
		nt_enabled = FALSE;
		netpoll_cleanup(&nt->np);
	}

	nt->enabled = enabled;

	return strnlen(buf, count);
}

static ssize_t store_dev_name(struct brcm_netconsole_target *nt,
			      const char *buf, size_t count)
{
	size_t len;

	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	strlcpy(nt->np.dev_name, buf, IFNAMSIZ);

	/* Get rid of possible trailing newline from echo(1) */
	len = strnlen(nt->np.dev_name, IFNAMSIZ);
	if ((len > 0) && (nt->np.dev_name[len - 1] == '\n'))
		nt->np.dev_name[len - 1] = '\0';

	return strnlen(buf, count);
}

static ssize_t store_local_port(struct brcm_netconsole_target *nt,
				const char *buf, size_t count)
{
	long local_port;
#define __U16_MAX	((__u16) ~0U)

	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	local_port = strtol10_check_range(buf, 0, __U16_MAX);
	if (local_port < 0)
		return local_port;

	nt->np.local_port = local_port;

	return strnlen(buf, count);
}

static ssize_t store_remote_port(struct brcm_netconsole_target *nt,
				 const char *buf, size_t count)
{
	long remote_port;
#define __U16_MAX	((__u16) ~0U)

	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	remote_port = strtol10_check_range(buf, 0, __U16_MAX);
	if (remote_port < 0)
		return remote_port;

	nt->np.remote_port = remote_port;

	return strnlen(buf, count);
}

static ssize_t store_local_ip(struct brcm_netconsole_target *nt,
			      const char *buf, size_t count)
{
	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	nt->np.local_ip.ip = in_aton(buf);

	return strnlen(buf, count);
}

static ssize_t store_remote_ip(struct brcm_netconsole_target *nt,
			       const char *buf, size_t count)
{
	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	nt->np.remote_ip.ip = in_aton(buf);

	return strnlen(buf, count);
}

static ssize_t store_remote_mac(struct brcm_netconsole_target *nt,
				const char *buf, size_t count)
{
	u8 remote_mac[ETH_ALEN];
	char *p = (char *)buf;
	int i;

	if (nt->enabled) {
		pr_err("brcm_netconsole: target (%s) is enabled, "
		       "disable to update parameters\n",
		       config_item_name(&nt->item));
		return -EINVAL;
	}

	for (i = 0; i < ETH_ALEN - 1; i++) {
		remote_mac[i] = simple_strtoul(p, &p, 16);
		if (*p != ':')
			goto invalid;
		p++;
	}
	remote_mac[ETH_ALEN - 1] = simple_strtoul(p, &p, 16);
	if (*p && (*p != '\n'))
		goto invalid;

	memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);

	return strnlen(buf, count);

invalid:
	pr_err("brcm_netconsole: invalid input\n");
	return -EINVAL;
}

/*
 * Attribute definitions for brcm_netconsole_target.
 */

#define BRCM_NETCONSOLE_TARGET_ATTR_RO(_name)				\
static struct brcm_netconsole_target_attr brcm_netconsole_target_##_name =	\
	__CONFIGFS_ATTR(_name, S_IRUGO, show_##_name, NULL)

#define BRCM_NETCONSOLE_TARGET_ATTR_RW(_name)				\
static struct brcm_netconsole_target_attr brcm_netconsole_target_##_name =	\
	__CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)

BRCM_NETCONSOLE_TARGET_ATTR_RW(enabled);
BRCM_NETCONSOLE_TARGET_ATTR_RW(dev_name);
BRCM_NETCONSOLE_TARGET_ATTR_RW(local_port);
BRCM_NETCONSOLE_TARGET_ATTR_RW(remote_port);
BRCM_NETCONSOLE_TARGET_ATTR_RW(local_ip);
BRCM_NETCONSOLE_TARGET_ATTR_RW(remote_ip);
BRCM_NETCONSOLE_TARGET_ATTR_RO(local_mac);
BRCM_NETCONSOLE_TARGET_ATTR_RW(remote_mac);

static struct configfs_attribute *brcm_netconsole_target_attrs[] = {
	&brcm_netconsole_target_enabled.attr,
	&brcm_netconsole_target_dev_name.attr,
	&brcm_netconsole_target_local_port.attr,
	&brcm_netconsole_target_remote_port.attr,
	&brcm_netconsole_target_local_ip.attr,
	&brcm_netconsole_target_remote_ip.attr,
	&brcm_netconsole_target_local_mac.attr,
	&brcm_netconsole_target_remote_mac.attr,
	NULL,
};

/*
 * Item operations and type for brcm_netconsole_target.
 */

static void brcm_netconsole_target_release(struct config_item *item)
{
	kfree(to_target(item));
}

static ssize_t brcm_netconsole_target_attr_show(struct config_item *item,
						struct configfs_attribute *attr,
						char *buf)
{
	ssize_t ret = -EINVAL;
	struct brcm_netconsole_target *nt = to_target(item);
	struct brcm_netconsole_target_attr *na =
	    container_of(attr, struct brcm_netconsole_target_attr, attr);

	if (na->show)
		ret = na->show(nt, buf);

	return ret;
}

static ssize_t brcm_netconsole_target_attr_store(
				struct config_item *item,
				struct configfs_attribute *attr,
				const char *buf,
				size_t count)
{
	ssize_t ret = -EINVAL;
	struct brcm_netconsole_target *nt = to_target(item);
	struct brcm_netconsole_target_attr *na =
	    container_of(attr, struct brcm_netconsole_target_attr, attr);

	if (na->store)
		ret = na->store(nt, buf, count);

	return ret;
}

static struct configfs_item_operations brcm_netconsole_target_item_ops = {
	.release = brcm_netconsole_target_release,
	.show_attribute = brcm_netconsole_target_attr_show,
	.store_attribute = brcm_netconsole_target_attr_store,
};

static struct config_item_type brcm_netconsole_target_type = {
	.ct_attrs = brcm_netconsole_target_attrs,
	.ct_item_ops = &brcm_netconsole_target_item_ops,
	.ct_owner = THIS_MODULE,
};

/*
 * Group operations and type for brcm_netconsole_subsys.
 */

static struct config_item *make_brcm_netconsole_target(struct config_group
						       *group, const char *name)
{
	unsigned long flags;
	struct brcm_netconsole_target *nt, *tmp;
	u8 remote_mac[ETH_ALEN];

	/* Remove the previous brcm_netconsole_target */
	if (!list_empty(&target_list)) {
		list_for_each_entry_safe(nt, tmp, &target_list, list) {
			pr_info("%s: remove previous nt->list\n", __func__);
			if (brcm_netconsole_cb->stop)
				brcm_netconsole_cb->stop();
			nt_enabled = FALSE;
			list_del(&nt->list);
			free_param_target(nt);
		}
	}

	/*
	 * Allocate and initialize with defaults.
	 * Target is disabled at creation (enabled == 0).
	 */
	nt = kzalloc(sizeof(*nt), GFP_KERNEL);
	if (!nt) {
		pr_err("brcm_netconsole: failed to allocate memory\n");
		return ERR_PTR(-ENOMEM);
	}

	nt->np.name = "brcm_netconsole";
	strlcpy(nt->np.dev_name, "rndis0", IFNAMSIZ);
	nt->np.local_port = 5042;
	nt->np.remote_port = 5042;
	remote_mac[0] = 0xaa;
	remote_mac[1] = 0xbb;
	remote_mac[2] = 0xcc;
	remote_mac[3] = 0xdd;
	remote_mac[4] = 0xee;
	remote_mac[5] = 0xff;
	memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
	nt->np.remote_ip.ip = in_aton("255.255.255.255");
	nt->np.local_ip.ip = in_aton("192.168.42.129");

	/* Initialize the config_item member */
	config_item_init_type_name(&nt->item, name,
				   &brcm_netconsole_target_type);

	/* Adding, but it is disabled */
	spin_lock_irqsave(&target_list_lock, flags);
	list_add(&nt->list, &target_list);
	spin_unlock_irqrestore(&target_list_lock, flags);

	return &nt->item;
}

static void drop_brcm_netconsole_target(struct config_group *group,
					struct config_item *item)
{
	unsigned long flags;
	struct brcm_netconsole_target *nt = to_target(item);

	spin_lock_irqsave(&target_list_lock, flags);
	list_del(&nt->list);
	spin_unlock_irqrestore(&target_list_lock, flags);

	/*
	 * The target may have never been enabled, or was manually disabled
	 * before being removed so netpoll may have already been cleaned up.
	 */
	if (nt->enabled)
		netpoll_cleanup(&nt->np);

	config_item_put(&nt->item);
}

static struct configfs_group_operations brcm_netconsole_subsys_group_ops = {
	.make_item = make_brcm_netconsole_target,
	.drop_item = drop_brcm_netconsole_target,
};

static struct config_item_type brcm_netconsole_subsys_type = {
	.ct_group_ops = &brcm_netconsole_subsys_group_ops,
	.ct_owner = THIS_MODULE,
};

/* The brcm_netconsole configfs subsystem */
static struct configfs_subsystem brcm_netconsole_subsys = {
	.su_group = {
		     .cg_item = {
				 .ci_namebuf = "brcm_netconsole",
				 .ci_type = &brcm_netconsole_subsys_type,
				 },
		     },
};

#endif /* CONFIG_BRCM_NETCONSOLE_DYNAMIC */

/**
* This function is called to register the callback functions for logging modules.
*
* @return    1: ready to send to logging data; 0: not ready to send the logging data.
*
*/
char brcm_netconsole_register_callbacks(struct brcm_netconsole_callbacks *_cb)
{
	pr_info("%s\n", __func__);

	brcm_netconsole_cb = _cb;

	if (brcm_netconsole_ready)
		return 1;	/* logging is ready to send */
	else
		return 0;	/* logging is not ready to send */
}
EXPORT_SYMBOL(brcm_netconsole_register_callbacks);

/* .... to be discarded .... */
unsigned char brcm_get_netcon_status(void)
{
	pr_info("%s: rndis is %s...\n", __func__,
		cur_rndis_status ? "on" : "off");
	return cur_rndis_status;
}
EXPORT_SYMBOL(brcm_get_netcon_status);

/**
* This function is called to call the callback functions to start/stop the logging.
*
** @param[in]  status the USB ethernet connection status.
*
*/
void brcm_current_netcon_status(unsigned char status)
{
	unsigned long flags;
	static struct brcm_netconsole_target *nt;

	pr_info("%s\n", __func__);

	if (list_empty(&target_list)) {
		pr_info("1. list_empty\n");
		nt = alloc_param_target(NULL);
		if (IS_ERR(nt))
			return;

		spin_lock_irqsave(&target_list_lock, flags);
		list_add(&nt->list, &target_list);
		spin_unlock_irqrestore(&target_list_lock, flags);
	} else {
		if (nt != NULL) {
			pr_info("2. setup/cleanup netpoll\n");
			brcm_netconsole_target_get(nt);
#ifndef CONFIG_ARCH_ISLAND
			if (status)
				netpoll_setup(&nt->np);
			else if (cur_rndis_status)
				netpoll_cleanup(&nt->np);
#endif
			brcm_netconsole_target_put(nt);
		} else
			pr_warn("nt is NULL!");
	}

	cur_rndis_status = status;
	/* Start/stop broadcom logging.... */
	if (cur_rndis_status && nt_enabled) {
		if (brcm_netconsole_cb->start)
			brcm_netconsole_cb->start();
	} else if (brcm_netconsole_cb->stop)
		brcm_netconsole_cb->stop();

	pr_info("status= %d, nt_enabled = %d\n", status, nt_enabled);

}
EXPORT_SYMBOL(brcm_current_netcon_status);

/* Handle network interface device notifications */
static int brcm_netconsole_netdev_event(struct notifier_block *this,
					unsigned long event, void *ptr)
{
	unsigned long flags;
	struct brcm_netconsole_target *nt;
	struct net_device *dev = ptr;

	if (!(event == NETDEV_CHANGENAME))
		goto done;

	spin_lock_irqsave(&target_list_lock, flags);
	list_for_each_entry(nt, &target_list, list) {
		brcm_netconsole_target_get(nt);

		if (nt->np.dev == dev)
			strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);

		brcm_netconsole_target_put(nt);
	}
	spin_unlock_irqrestore(&target_list_lock, flags);

done:
	return NOTIFY_DONE;
}

static struct notifier_block brcm_netconsole_netdev_notifier = {
	.notifier_call = brcm_netconsole_netdev_event,
};

static void write_msg(struct brcm_console *con, const char *msg,
		      unsigned int len)
{
	int frag, left;
	unsigned long flags;
	struct brcm_netconsole_target *nt;
	const char *tmp;

	/* Avoid taking lock and disabling interrupts unnecessarily */
	if (list_empty(&target_list))
		return;

	spin_lock_irqsave(&target_list_lock, flags);
	list_for_each_entry(nt, &target_list, list) {
		brcm_netconsole_target_get(nt);
		if (nt->enabled && netif_running(nt->np.dev)
		    && netif_carrier_ok(nt->np.dev)) {
			/*
			 * We nest this inside the for-each-target loop above
			 * so that we're able to get as much logging out to
			 * at least one target if we die inside here, instead
			 * of unnecessarily keeping all targets in lock-step.
			 */
			tmp = msg;

			for (left = len; left;) {
				frag = min(left, MAX_PRINT_CHUNK);
				netpoll_send_udp(&nt->np, tmp, frag);
				tmp += frag;
				left -= frag;
			}
		}
		brcm_netconsole_target_put(nt);
	}
	spin_unlock_irqrestore(&target_list_lock, flags);
}

/*
 * int brcm_klogging(char *data, int length)
 * This function is for BMTT logging API to call to send the logging through USB to PC.
 *
 * @return the number of bytes have been sent out.
 */

int brcm_klogging(char *data, int length)
{

	int frag, left, len_sent = 0;
	unsigned long flags;
	struct brcm_netconsole_target *nt;
	const char *tmp;

	/* Avoid taking lock and disabling interrupts unnecessarily */
	if (list_empty(&target_list))
		return len_sent;

	spin_lock_irqsave(&target_list_lock, flags);
	list_for_each_entry(nt, &target_list, list) {
		brcm_netconsole_target_get(nt);
		if (nt->enabled && netif_running(nt->np.dev)
		    && netif_carrier_ok(nt->np.dev)) {

			if (netpoll_free_memory() == 0) {
				brcm_netconsole_target_put(nt);
				spin_unlock_irqrestore(&target_list_lock,
						       flags);
				return 0;
			}
			/*
			 * We nest this inside the for-each-target loop above
			 * so that we're able to get as much logging out to
			 * at least one target if we die inside here, instead
			 * of unnecessarily keeping all targets in lock-step.
			 */
			tmp = data;

			for (left = length; left;) {
				frag = min(left, MAX_PRINT_CHUNK);

				if (frag > netpoll_free_memory())
					goto end_of_send;

				netpoll_send_udp(&nt->np, tmp, frag);
				tmp += frag;
				left -= frag;
				len_sent += frag;
			}
		}
end_of_send:
		brcm_netconsole_target_put(nt);
	}
	spin_unlock_irqrestore(&target_list_lock, flags);
	return len_sent;
}
EXPORT_SYMBOL(brcm_klogging);

static struct brcm_console brcm_netconsole = {
	.name = "netcon",
	.flags = CON_ENABLED,
	.write = write_msg,
};

static int __init init_brcm_netconsole(void)
{
	int err;
	struct brcm_netconsole_target *nt, *tmp;
	unsigned long flags;
	char *target_config;
	char *input = config;

	if (strnlen(input, MAX_PARAM_LENGTH)) {
		while ((target_config = strsep(&input, ";"))) {
			nt = alloc_param_target(target_config);
			if (IS_ERR(nt)) {
				err = PTR_ERR(nt);
				goto fail;
			}
			/* Dump existing printks when we register */
			brcm_netconsole.flags |= CON_PRINTBUFFER;

			spin_lock_irqsave(&target_list_lock, flags);
			list_add(&nt->list, &target_list);
			spin_unlock_irqrestore(&target_list_lock, flags);
		}
	}

	err = register_netdevice_notifier(&brcm_netconsole_netdev_notifier);
	if (err)
		goto fail;

	err = dynamic_brcm_netconsole_init();
	if (err)
		goto undonotifier;

/*	register_brcm_console(&brcm_netconsole); */
	pr_info("brcm_netconsole: network logging started\n");

	return err;

undonotifier:
	unregister_netdevice_notifier(&brcm_netconsole_netdev_notifier);

fail:
	pr_err("brcm_netconsole: cleaning up\n");

	/*
	 * Remove all targets and destroy them (only targets created
	 * from the boot/module option exist here). Skipping the list
	 * lock is safe here, and netpoll_cleanup() will sleep.
	 */
	list_for_each_entry_safe(nt, tmp, &target_list, list) {
		list_del(&nt->list);
		free_param_target(nt);
	}

	return err;
}

static void __exit cleanup_brcm_netconsole(void)
{
	struct brcm_netconsole_target *nt, *tmp;

/*	unregister_brcm_console(&brcm_netconsole); */
	dynamic_brcm_netconsole_exit();
	unregister_netdevice_notifier(&brcm_netconsole_netdev_notifier);

	/*
	 * Targets created via configfs pin references on our module
	 * and would first be rmdir(2)'ed from userspace. We reach
	 * here only when they are already destroyed, and only those
	 * created from the boot/module option are left, so remove and
	 * destroy them. Skipping the list lock is safe here, and
	 * netpoll_cleanup() will sleep.
	 */
	list_for_each_entry_safe(nt, tmp, &target_list, list) {
		list_del(&nt->list);
		free_param_target(nt);
	}
}

module_init(init_brcm_netconsole);
module_exit(cleanup_brcm_netconsole);