drivers/scsi/fcoe/fcoe_transport.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope 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.,
  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Maintained at www.Open-FCoE.org
  */

 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/errno.h>
 #include <scsi/libfcoe.h>

 #include "libfcoe.h"

 MODULE_AUTHOR("Open-FCoE.org");
 MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
 MODULE_LICENSE("GPL v2");

 static int fcoe_transport_create(const char *, struct kernel_param *);
 static int fcoe_transport_destroy(const char *, struct kernel_param *);
 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp);
 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *device);
 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *device);
 static int fcoe_transport_enable(const char *, struct kernel_param *);
 static int fcoe_transport_disable(const char *, struct kernel_param *);

 static LIST_HEAD(fcoe_transports);
 static LIST_HEAD(fcoe_netdevs);
 static DEFINE_MUTEX(ft_mutex);

 unsigned int libfcoe_debug_logging;
 module_param_named(debug_logging, libfcoe_debug_logging, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");

 module_param_call(show, NULL, fcoe_transport_show, NULL, S_IRUSR);
 __MODULE_PARM_TYPE(show, "string");
 MODULE_PARM_DESC(show, " Show attached FCoE transports");

 module_param_call(create, fcoe_transport_create, NULL,
 		  (void *)FIP_MODE_FABRIC, S_IWUSR);
 __MODULE_PARM_TYPE(create, "string");
 MODULE_PARM_DESC(create, " Creates fcoe instance on a ethernet interface");

 module_param_call(create_vn2vn, fcoe_transport_create, NULL,
 		  (void *)FIP_MODE_VN2VN, S_IWUSR);
 __MODULE_PARM_TYPE(create_vn2vn, "string");
 MODULE_PARM_DESC(create_vn2vn, " Creates a VN_node to VN_node FCoE instance "
 		 "on an Ethernet interface");

 module_param_call(destroy, fcoe_transport_destroy, NULL, NULL, S_IWUSR);
 __MODULE_PARM_TYPE(destroy, "string");
 MODULE_PARM_DESC(destroy, " Destroys fcoe instance on a ethernet interface");

 module_param_call(enable, fcoe_transport_enable, NULL, NULL, S_IWUSR);
 __MODULE_PARM_TYPE(enable, "string");
 MODULE_PARM_DESC(enable, " Enables fcoe on a ethernet interface.");

 module_param_call(disable, fcoe_transport_disable, NULL, NULL, S_IWUSR);
 __MODULE_PARM_TYPE(disable, "string");
 MODULE_PARM_DESC(disable, " Disables fcoe on a ethernet interface.");

 /**
  * fcoe_transport_lookup - find an fcoe transport that matches a netdev
  * @netdev: The netdev to look for from all attached transports
  *
  * Returns : ptr to the fcoe transport that supports this netdev or NULL
  * if not found.
  *
  * The ft_mutex should be held when this is called
  */
 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *netdev)
 {
 	struct fcoe_transport *ft = NULL;

 	list_for_each_entry(ft, &fcoe_transports, list)
 		if (ft->match && ft->match(netdev))
 			return ft;
 	return NULL;
 }

 /**
  * fcoe_transport_attach - Attaches an FCoE transport
  * @ft: The fcoe transport to be attached
  *
  * Returns : 0 for success
  */
 int fcoe_transport_attach(struct fcoe_transport *ft)
 {
 	int rc = 0;

 	mutex_lock(&ft_mutex);
 	if (ft->attached) {
 		LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
 				       ft->name);
 		rc = -EEXIST;
 		goto out_attach;
 	}

 	/* Add default transport to the tail */
 	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
 		list_add(&ft->list, &fcoe_transports);
 	else
 		list_add_tail(&ft->list, &fcoe_transports);

 	ft->attached = true;
 	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);

 out_attach:
 	mutex_unlock(&ft_mutex);
 	return rc;
 }
 EXPORT_SYMBOL(fcoe_transport_attach);

 /**
  * fcoe_transport_attach - Detaches an FCoE transport
  * @ft: The fcoe transport to be attached
  *
  * Returns : 0 for success
  */
 int fcoe_transport_detach(struct fcoe_transport *ft)
 {
 	int rc = 0;

 	mutex_lock(&ft_mutex);
 	if (!ft->attached) {
 		LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
 			ft->name);
 		rc = -ENODEV;
 		goto out_attach;
 	}

 	list_del(&ft->list);
 	ft->attached = false;
 	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);

 out_attach:
 	mutex_unlock(&ft_mutex);
 	return rc;

 }
 EXPORT_SYMBOL(fcoe_transport_detach);

 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp)
 {
 	int i, j;
 	struct fcoe_transport *ft = NULL;

 	i = j = sprintf(buffer, "Attached FCoE transports:");
 	mutex_lock(&ft_mutex);
 	list_for_each_entry(ft, &fcoe_transports, list) {
 		i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
 		if (i >= PAGE_SIZE)
 			break;
 	}
 	mutex_unlock(&ft_mutex);
 	if (i == j)
 		i += snprintf(&buffer[i], IFNAMSIZ, "none");
 	return i;
 }

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

 static int __exit fcoe_transport_exit(void)
 {
 	struct fcoe_transport *ft;

 	mutex_lock(&ft_mutex);
 	list_for_each_entry(ft, &fcoe_transports, list)
 		printk(KERN_ERR "FCoE transport %s is still attached!\n",
 		      ft->name);
 	mutex_unlock(&ft_mutex);
 	return 0;
 }


 static int fcoe_add_netdev_mapping(struct net_device *netdev,
 					struct fcoe_transport *ft)
 {
 	struct fcoe_netdev_mapping *nm;

 	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
 	if (!nm) {
 		printk(KERN_ERR "Unable to allocate netdev_mapping");
 		return -ENOMEM;
 	}

 	nm->netdev = netdev;
 	nm->ft = ft;

 	list_add(&nm->list, &fcoe_netdevs);
 	return 0;
 }


 static void fcoe_del_netdev_mapping(struct net_device *netdev)
 {
 	struct fcoe_netdev_mapping *nm = NULL, *tmp;

 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
 		if (nm->netdev == netdev) {
 			list_del(&nm->list);
 			kfree(nm);
 			return;
 		}
 	}
 }


 /**
  * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
  * it was created
  *
  * Returns : ptr to the fcoe transport that supports this netdev or NULL
  * if not found.
  *
  * The ft_mutex should be held when this is called
  */
 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *netdev)
 {
 	struct fcoe_transport *ft = NULL;
 	struct fcoe_netdev_mapping *nm;

 	list_for_each_entry(nm, &fcoe_netdevs, list) {
 		if (netdev == nm->netdev) {
 			ft = nm->ft;
 			return ft;
 		}
 	}

 	return NULL;
 }

 /**
  * fcoe_if_to_netdev() - Parse a name buffer to get a net device
  * @buffer: The name of the net device
  *
  * Returns: NULL or a ptr to net_device
  */
 static struct net_device *fcoe_if_to_netdev(const char *buffer)
 {
 	char *cp;
 	char ifname[IFNAMSIZ + 2];

 	if (buffer) {
 		strlcpy(ifname, buffer, IFNAMSIZ);
 		cp = ifname + strlen(ifname);
 		while (--cp >= ifname && *cp == '\n')
 			*cp = '\0';
 		return dev_get_by_name(&init_net, ifname);
 	}
 	return NULL;
 }

 /**
  * fcoe_transport_create() - Create a fcoe interface
  * @buffer: The name of the Ethernet interface to create on
  * @kp:	    The associated kernel param
  *
  * Called from sysfs. This holds the ft_mutex while calling the
  * registered fcoe transport's create function.
  *
  * Returns: 0 for success
  */
 static int fcoe_transport_create(const char *buffer, struct kernel_param *kp)
 {
 	int rc = -ENODEV;
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;
 	enum fip_state fip_mode = (enum fip_state)(long)kp->arg;

 	if (!mutex_trylock(&ft_mutex))
 		return restart_syscall();

 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
 	 * removed.  Module parameter sysfs files are writable before the
 	 * module_init function is called and after module_exit.
 	 */
 	if (THIS_MODULE->state != MODULE_STATE_LIVE)
 		goto out_nodev;
 #endif

 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev) {
 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
 		goto out_nodev;
 	}

 	ft = fcoe_netdev_map_lookup(netdev);
 	if (ft) {
 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
 				      "FCoE instance on %s.\n",
 				      ft->name, netdev->name);
 		rc = -EEXIST;
 		goto out_putdev;
 	}

 	ft = fcoe_transport_lookup(netdev);
 	if (!ft) {
 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
 				      netdev->name);
 		goto out_putdev;
 	}

 	rc = fcoe_add_netdev_mapping(netdev, ft);
 	if (rc) {
 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
 				      "for FCoE transport %s for %s.\n",
 				      ft->name, netdev->name);
 		goto out_putdev;
 	}

 	/* pass to transport create */
 	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
 	if (rc)
 		fcoe_del_netdev_mapping(netdev);

 	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
 			      ft->name, (rc) ? "failed" : "succeeded",
 			      netdev->name);

 out_putdev:
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);
 	if (rc == -ERESTARTSYS)
 		return restart_syscall();
 	else
 		return rc;
 }

 /**
  * fcoe_transport_destroy() - Destroy a FCoE interface
  * @buffer: The name of the Ethernet interface to be destroyed
  * @kp:	    The associated kernel parameter
  *
  * Called from sysfs. This holds the ft_mutex while calling the
  * registered fcoe transport's destroy function.
  *
  * Returns: 0 for success
  */
 static int fcoe_transport_destroy(const char *buffer, struct kernel_param *kp)
 {
 	int rc = -ENODEV;
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;

 	if (!mutex_trylock(&ft_mutex))
 		return restart_syscall();

 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
 	 * removed.  Module parameter sysfs files are writable before the
 	 * module_init function is called and after module_exit.
 	 */
 	if (THIS_MODULE->state != MODULE_STATE_LIVE)
 		goto out_nodev;
 #endif

 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev) {
 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
 		goto out_nodev;
 	}

 	ft = fcoe_netdev_map_lookup(netdev);
 	if (!ft) {
 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
 				      netdev->name);
 		goto out_putdev;
 	}

 	/* pass to transport destroy */
 	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
 	fcoe_del_netdev_mapping(netdev);
 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
 			      ft->name, (rc) ? "failed" : "succeeded",
 			      netdev->name);

 out_putdev:
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);

 	if (rc == -ERESTARTSYS)
 		return restart_syscall();
 	else
 		return rc;
 }

 /**
  * fcoe_transport_disable() - Disables a FCoE interface
  * @buffer: The name of the Ethernet interface to be disabled
  * @kp:	    The associated kernel parameter
  *
  * Called from sysfs.
  *
  * Returns: 0 for success
  */
 static int fcoe_transport_disable(const char *buffer, struct kernel_param *kp)
 {
 	int rc = -ENODEV;
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;

 	if (!mutex_trylock(&ft_mutex))
 		return restart_syscall();

 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
 	 * removed.  Module parameter sysfs files are writable before the
 	 * module_init function is called and after module_exit.
 	 */
 	if (THIS_MODULE->state != MODULE_STATE_LIVE)
 		goto out_nodev;
 #endif

 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev)
 		goto out_nodev;

 	ft = fcoe_netdev_map_lookup(netdev);
 	if (!ft)
 		goto out_putdev;

 	rc = ft->disable ? ft->disable(netdev) : -ENODEV;

 out_putdev:
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);

 	if (rc == -ERESTARTSYS)
 		return restart_syscall();
 	else
 		return rc;
 }

 /**
  * fcoe_transport_enable() - Enables a FCoE interface
  * @buffer: The name of the Ethernet interface to be enabled
  * @kp:     The associated kernel parameter
  *
  * Called from sysfs.
  *
  * Returns: 0 for success
  */
 static int fcoe_transport_enable(const char *buffer, struct kernel_param *kp)
 {
 	int rc = -ENODEV;
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;

 	if (!mutex_trylock(&ft_mutex))
 		return restart_syscall();

 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
 	 * removed.  Module parameter sysfs files are writable before the
 	 * module_init function is called and after module_exit.
 	 */
 	if (THIS_MODULE->state != MODULE_STATE_LIVE)
 		goto out_nodev;
 #endif

 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev)
 		goto out_nodev;

 	ft = fcoe_netdev_map_lookup(netdev);
 	if (!ft)
 		goto out_putdev;

 	rc = ft->enable ? ft->enable(netdev) : -ENODEV;

 out_putdev:
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);
 	if (rc == -ERESTARTSYS)
 		return restart_syscall();
 	else
 		return rc;
 }

 /**
  * libfcoe_init() - Initialization routine for libfcoe.ko
  */
 static int __init libfcoe_init(void)
 {
 	fcoe_transport_init();

 	return 0;
 }
 module_init(libfcoe_init);

 /**
  * libfcoe_exit() - Tear down libfcoe.ko
  */
 static void __exit libfcoe_exit(void)
 {
 	fcoe_transport_exit();
 }
 module_exit(libfcoe_exit);
	/*
	* Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope 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.,
	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Maintained at www.Open-FCoE.org
	*/

	#include <linux/types.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/list.h>
	#include <linux/netdevice.h>
	#include <linux/errno.h>
	#include <scsi/libfcoe.h>

	#include "libfcoe.h"

	MODULE_AUTHOR("Open-FCoE.org");
	MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
	MODULE_LICENSE("GPL v2");

	static int fcoe_transport_create(const char , struct kernel_param );
	static int fcoe_transport_destroy(const char , struct kernel_param );
	static int fcoe_transport_show(char buffer, const struct kernel_param kp);
	static struct fcoe_transport fcoe_transport_lookup(struct net_device device);
	static struct fcoe_transport fcoe_netdev_map_lookup(struct net_device device);
	static int fcoe_transport_enable(const char , struct kernel_param );
	static int fcoe_transport_disable(const char , struct kernel_param );

	static LIST_HEAD(fcoe_transports);
	static LIST_HEAD(fcoe_netdevs);
	static DEFINE_MUTEX(ft_mutex);

	unsigned int libfcoe_debug_logging;
	module_param_named(debug_logging, libfcoe_debug_logging, int, S_IRUGO\|S_IWUSR);
	MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");

	module_param_call(show, NULL, fcoe_transport_show, NULL, S_IRUSR);
	__MODULE_PARM_TYPE(show, "string");
	MODULE_PARM_DESC(show, " Show attached FCoE transports");

	module_param_call(create, fcoe_transport_create, NULL,
	(void *)FIP_MODE_FABRIC, S_IWUSR);
	__MODULE_PARM_TYPE(create, "string");
	MODULE_PARM_DESC(create, " Creates fcoe instance on a ethernet interface");

	module_param_call(create_vn2vn, fcoe_transport_create, NULL,
	(void *)FIP_MODE_VN2VN, S_IWUSR);
	__MODULE_PARM_TYPE(create_vn2vn, "string");
	MODULE_PARM_DESC(create_vn2vn, " Creates a VN_node to VN_node FCoE instance "
	"on an Ethernet interface");

	module_param_call(destroy, fcoe_transport_destroy, NULL, NULL, S_IWUSR);
	__MODULE_PARM_TYPE(destroy, "string");
	MODULE_PARM_DESC(destroy, " Destroys fcoe instance on a ethernet interface");

	module_param_call(enable, fcoe_transport_enable, NULL, NULL, S_IWUSR);
	__MODULE_PARM_TYPE(enable, "string");
	MODULE_PARM_DESC(enable, " Enables fcoe on a ethernet interface.");

	module_param_call(disable, fcoe_transport_disable, NULL, NULL, S_IWUSR);
	__MODULE_PARM_TYPE(disable, "string");
	MODULE_PARM_DESC(disable, " Disables fcoe on a ethernet interface.");

	/**
	* fcoe_transport_lookup - find an fcoe transport that matches a netdev
	* @netdev: The netdev to look for from all attached transports
	*
	* Returns : ptr to the fcoe transport that supports this netdev or NULL
	* if not found.
	*
	* The ft_mutex should be held when this is called
	*/
	static struct fcoe_transport fcoe_transport_lookup(struct net_device netdev)
	{
	struct fcoe_transport *ft = NULL;

	list_for_each_entry(ft, &fcoe_transports, list)
	if (ft->match && ft->match(netdev))
	return ft;
	return NULL;
	}

	/**
	* fcoe_transport_attach - Attaches an FCoE transport
	* @ft: The fcoe transport to be attached
	*
	* Returns : 0 for success
	*/
	int fcoe_transport_attach(struct fcoe_transport *ft)
	{
	int rc = 0;

	mutex_lock(&ft_mutex);
	if (ft->attached) {
	LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
	ft->name);
	rc = -EEXIST;
	goto out_attach;
	}

	/* Add default transport to the tail */
	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
	list_add(&ft->list, &fcoe_transports);
	else
	list_add_tail(&ft->list, &fcoe_transports);

	ft->attached = true;
	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);

	out_attach:
	mutex_unlock(&ft_mutex);
	return rc;
	}
	EXPORT_SYMBOL(fcoe_transport_attach);

	/**
	* fcoe_transport_attach - Detaches an FCoE transport
	* @ft: The fcoe transport to be attached
	*
	* Returns : 0 for success
	*/
	int fcoe_transport_detach(struct fcoe_transport *ft)
	{
	int rc = 0;

	mutex_lock(&ft_mutex);
	if (!ft->attached) {
	LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
	ft->name);
	rc = -ENODEV;
	goto out_attach;
	}

	list_del(&ft->list);
	ft->attached = false;
	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);

	out_attach:
	mutex_unlock(&ft_mutex);
	return rc;

	}
	EXPORT_SYMBOL(fcoe_transport_detach);

	static int fcoe_transport_show(char buffer, const struct kernel_param kp)
	{
	int i, j;
	struct fcoe_transport *ft = NULL;

	i = j = sprintf(buffer, "Attached FCoE transports:");
	mutex_lock(&ft_mutex);
	list_for_each_entry(ft, &fcoe_transports, list) {
	i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
	if (i >= PAGE_SIZE)
	break;
	}
	mutex_unlock(&ft_mutex);
	if (i == j)
	i += snprintf(&buffer[i], IFNAMSIZ, "none");
	return i;
	}

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

	static int __exit fcoe_transport_exit(void)
	{
	struct fcoe_transport *ft;

	mutex_lock(&ft_mutex);
	list_for_each_entry(ft, &fcoe_transports, list)
	printk(KERN_ERR "FCoE transport %s is still attached!\n",
	ft->name);
	mutex_unlock(&ft_mutex);
	return 0;
	}


	static int fcoe_add_netdev_mapping(struct net_device *netdev,
	struct fcoe_transport *ft)
	{
	struct fcoe_netdev_mapping *nm;

	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
	if (!nm) {
	printk(KERN_ERR "Unable to allocate netdev_mapping");
	return -ENOMEM;
	}

	nm->netdev = netdev;
	nm->ft = ft;

	list_add(&nm->list, &fcoe_netdevs);
	return 0;
	}


	static void fcoe_del_netdev_mapping(struct net_device *netdev)
	{
	struct fcoe_netdev_mapping nm = NULL, tmp;

	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
	if (nm->netdev == netdev) {
	list_del(&nm->list);
	kfree(nm);
	return;
	}
	}
	}


	/**
	* fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
	* it was created
	*
	* Returns : ptr to the fcoe transport that supports this netdev or NULL
	* if not found.
	*
	* The ft_mutex should be held when this is called
	*/
	static struct fcoe_transport fcoe_netdev_map_lookup(struct net_device netdev)
	{
	struct fcoe_transport *ft = NULL;
	struct fcoe_netdev_mapping *nm;

	list_for_each_entry(nm, &fcoe_netdevs, list) {
	if (netdev == nm->netdev) {
	ft = nm->ft;
	return ft;
	}
	}

	return NULL;
	}

	/**
	* fcoe_if_to_netdev() - Parse a name buffer to get a net device
	* @buffer: The name of the net device
	*
	* Returns: NULL or a ptr to net_device
	*/
	static struct net_device fcoe_if_to_netdev(const char buffer)
	{
	char *cp;
	char ifname[IFNAMSIZ + 2];

	if (buffer) {
	strlcpy(ifname, buffer, IFNAMSIZ);
	cp = ifname + strlen(ifname);
	while (--cp >= ifname && *cp == '\n')
	*cp = '\0';
	return dev_get_by_name(&init_net, ifname);
	}
	return NULL;
	}

	/**
	* fcoe_transport_create() - Create a fcoe interface
	* @buffer: The name of the Ethernet interface to create on
	* @kp: The associated kernel param
	*
	* Called from sysfs. This holds the ft_mutex while calling the
	* registered fcoe transport's create function.
	*
	* Returns: 0 for success
	*/
	static int fcoe_transport_create(const char buffer, struct kernel_param kp)
	{
	int rc = -ENODEV;
	struct net_device *netdev = NULL;
	struct fcoe_transport *ft = NULL;
	enum fip_state fip_mode = (enum fip_state)(long)kp->arg;

	if (!mutex_trylock(&ft_mutex))
	return restart_syscall();

	#ifdef CONFIG_LIBFCOE_MODULE
	/*
	* Make sure the module has been initialized, and is not about to be
	* removed. Module parameter sysfs files are writable before the
	* module_init function is called and after module_exit.
	*/
	if (THIS_MODULE->state != MODULE_STATE_LIVE)
	goto out_nodev;
	#endif

	netdev = fcoe_if_to_netdev(buffer);
	if (!netdev) {
	LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
	goto out_nodev;
	}

	ft = fcoe_netdev_map_lookup(netdev);
	if (ft) {
	LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
	"FCoE instance on %s.\n",
	ft->name, netdev->name);
	rc = -EEXIST;
	goto out_putdev;
	}

	ft = fcoe_transport_lookup(netdev);
	if (!ft) {
	LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
	netdev->name);
	goto out_putdev;
	}

	rc = fcoe_add_netdev_mapping(netdev, ft);
	if (rc) {
	LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
	"for FCoE transport %s for %s.\n",
	ft->name, netdev->name);
	goto out_putdev;
	}

	/* pass to transport create */
	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
	if (rc)
	fcoe_del_netdev_mapping(netdev);

	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
	ft->name, (rc) ? "failed" : "succeeded",
	netdev->name);

	out_putdev:
	dev_put(netdev);
	out_nodev:
	mutex_unlock(&ft_mutex);
	if (rc == -ERESTARTSYS)
	return restart_syscall();
	else
	return rc;
	}

	/**
	* fcoe_transport_destroy() - Destroy a FCoE interface
	* @buffer: The name of the Ethernet interface to be destroyed
	* @kp: The associated kernel parameter
	*
	* Called from sysfs. This holds the ft_mutex while calling the
	* registered fcoe transport's destroy function.
	*
	* Returns: 0 for success
	*/
	static int fcoe_transport_destroy(const char buffer, struct kernel_param kp)
	{
	int rc = -ENODEV;
	struct net_device *netdev = NULL;
	struct fcoe_transport *ft = NULL;

	if (!mutex_trylock(&ft_mutex))
	return restart_syscall();

	#ifdef CONFIG_LIBFCOE_MODULE
	/*
	* Make sure the module has been initialized, and is not about to be
	* removed. Module parameter sysfs files are writable before the
	* module_init function is called and after module_exit.
	*/
	if (THIS_MODULE->state != MODULE_STATE_LIVE)
	goto out_nodev;
	#endif

	netdev = fcoe_if_to_netdev(buffer);
	if (!netdev) {
	LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
	goto out_nodev;
	}

	ft = fcoe_netdev_map_lookup(netdev);
	if (!ft) {
	LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
	netdev->name);
	goto out_putdev;
	}

	/* pass to transport destroy */
	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
	fcoe_del_netdev_mapping(netdev);
	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
	ft->name, (rc) ? "failed" : "succeeded",
	netdev->name);

	out_putdev:
	dev_put(netdev);
	out_nodev:
	mutex_unlock(&ft_mutex);

	if (rc == -ERESTARTSYS)
	return restart_syscall();
	else
	return rc;
	}

	/**
	* fcoe_transport_disable() - Disables a FCoE interface
	* @buffer: The name of the Ethernet interface to be disabled
	* @kp: The associated kernel parameter
	*
	* Called from sysfs.
	*
	* Returns: 0 for success
	*/
	static int fcoe_transport_disable(const char buffer, struct kernel_param kp)
	{
	int rc = -ENODEV;
	struct net_device *netdev = NULL;
	struct fcoe_transport *ft = NULL;

	if (!mutex_trylock(&ft_mutex))
	return restart_syscall();

	#ifdef CONFIG_LIBFCOE_MODULE
	/*
	* Make sure the module has been initialized, and is not about to be
	* removed. Module parameter sysfs files are writable before the
	* module_init function is called and after module_exit.
	*/
	if (THIS_MODULE->state != MODULE_STATE_LIVE)
	goto out_nodev;
	#endif

	netdev = fcoe_if_to_netdev(buffer);
	if (!netdev)
	goto out_nodev;

	ft = fcoe_netdev_map_lookup(netdev);
	if (!ft)
	goto out_putdev;

	rc = ft->disable ? ft->disable(netdev) : -ENODEV;

	out_putdev:
	dev_put(netdev);
	out_nodev:
	mutex_unlock(&ft_mutex);

	if (rc == -ERESTARTSYS)
	return restart_syscall();
	else
	return rc;
	}

	/**
	* fcoe_transport_enable() - Enables a FCoE interface
	* @buffer: The name of the Ethernet interface to be enabled
	* @kp: The associated kernel parameter
	*
	* Called from sysfs.
	*
	* Returns: 0 for success
	*/
	static int fcoe_transport_enable(const char buffer, struct kernel_param kp)
	{
	int rc = -ENODEV;
	struct net_device *netdev = NULL;
	struct fcoe_transport *ft = NULL;

	if (!mutex_trylock(&ft_mutex))
	return restart_syscall();

	#ifdef CONFIG_LIBFCOE_MODULE
	/*
	* Make sure the module has been initialized, and is not about to be
	* removed. Module parameter sysfs files are writable before the
	* module_init function is called and after module_exit.
	*/
	if (THIS_MODULE->state != MODULE_STATE_LIVE)
	goto out_nodev;
	#endif

	netdev = fcoe_if_to_netdev(buffer);
	if (!netdev)
	goto out_nodev;

	ft = fcoe_netdev_map_lookup(netdev);
	if (!ft)
	goto out_putdev;

	rc = ft->enable ? ft->enable(netdev) : -ENODEV;

	out_putdev:
	dev_put(netdev);
	out_nodev:
	mutex_unlock(&ft_mutex);
	if (rc == -ERESTARTSYS)
	return restart_syscall();
	else
	return rc;
	}

	/**
	* libfcoe_init() - Initialization routine for libfcoe.ko
	*/
	static int __init libfcoe_init(void)
	{
	fcoe_transport_init();

	return 0;
	}
	module_init(libfcoe_init);

	/**
	* libfcoe_exit() - Tear down libfcoe.ko
	*/
	static void __exit libfcoe_exit(void)
	{
	fcoe_transport_exit();
	}
	module_exit(libfcoe_exit);