[SCSI] fcoe: removes fc_transport_fcoe.[ch] code files

/*

 * Copyright(c) 2007 - 2008 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/pci.h>

#include <scsi/libfcoe.h>

#include <scsi/fc_transport_fcoe.h>

/* internal fcoe transport */

struct fcoe_transport_internal {

	struct fcoe_transport *t;

	struct net_device *netdev;

	struct list_head list;

};

/* fcoe transports list and its lock */

static LIST_HEAD(fcoe_transports);

static DEFINE_MUTEX(fcoe_transports_lock);

/**

 * fcoe_transport_default() - Returns ptr to the default transport fcoe_sw

 */

struct fcoe_transport *fcoe_transport_default(void)

{

	return &fcoe_sw_transport;

}

/**

 * fcoe_transport_to_pcidev() - get the pci dev from a netdev

 * @netdev: the netdev that pci dev will be retrived from

 *

 * Returns: NULL or the corrsponding pci_dev

 */

struct pci_dev *fcoe_transport_pcidev(const struct net_device *netdev)

{

	if (!netdev->dev.parent)

		return NULL;

	return to_pci_dev(netdev->dev.parent);

}

/**

 * fcoe_transport_device_lookup() - Lookup a transport

 * @netdev: the netdev the transport to be attached to

 *

 * This will look for existing offload driver, if not found, it falls back to

 * the default sw hba (fcoe_sw) as its fcoe transport.

 *

 * Returns: 0 for success

 */

static struct fcoe_transport_internal *

fcoe_transport_device_lookup(struct fcoe_transport *t,

			     struct net_device *netdev)

{

	struct fcoe_transport_internal *ti;

	/* assign the transpor to this device */

	mutex_lock(&t->devlock);

	list_for_each_entry(ti, &t->devlist, list) {

		if (ti->netdev == netdev) {

			mutex_unlock(&t->devlock);

			return ti;

		}

	}

	mutex_unlock(&t->devlock);

	return NULL;

}

/**

 * fcoe_transport_device_add() - Assign a transport to a device

 * @netdev: the netdev the transport to be attached to

 *

 * This will look for existing offload driver, if not found, it falls back to

 * the default sw hba (fcoe_sw) as its fcoe transport.

 *

 * Returns: 0 for success

 */

static int fcoe_transport_device_add(struct fcoe_transport *t,

				     struct net_device *netdev)

{

	struct fcoe_transport_internal *ti;

	ti = fcoe_transport_device_lookup(t, netdev);

	if (ti) {

		printk(KERN_DEBUG "fcoe_transport_device_add:"

		       "device %s is already added to transport %s\n",

		       netdev->name, t->name);

		return -EEXIST;

	}

	/* allocate an internal struct to host the netdev and the list */

	ti = kzalloc(sizeof(*ti), GFP_KERNEL);

	if (!ti)

		return -ENOMEM;

	ti->t = t;

	ti->netdev = netdev;

	INIT_LIST_HEAD(&ti->list);

	dev_hold(ti->netdev);

	mutex_lock(&t->devlock);

	list_add(&ti->list, &t->devlist);

	mutex_unlock(&t->devlock);

	printk(KERN_DEBUG "fcoe_transport_device_add:"

		       "device %s added to transport %s\n",

		       netdev->name, t->name);

	return 0;

}

/**

 * fcoe_transport_device_remove() - Remove a device from its transport

 * @netdev: the netdev the transport to be attached to

 *

 * This removes the device from the transport so the given transport will

 * not manage this device any more

 *

 * Returns: 0 for success

 */

static int fcoe_transport_device_remove(struct fcoe_transport *t,

					struct net_device *netdev)

{

	struct fcoe_transport_internal *ti;

	ti = fcoe_transport_device_lookup(t, netdev);

	if (!ti) {

		printk(KERN_DEBUG "fcoe_transport_device_remove:"

		       "device %s is not managed by transport %s\n",

		       netdev->name, t->name);

		return -ENODEV;

	}

	mutex_lock(&t->devlock);

	list_del(&ti->list);

	mutex_unlock(&t->devlock);

	printk(KERN_DEBUG "fcoe_transport_device_remove:"

	       "device %s removed from transport %s\n",

	       netdev->name, t->name);

	dev_put(ti->netdev);

	kfree(ti);

	return 0;

}

/**

 * fcoe_transport_device_remove_all() - Remove all from transport devlist

 *

 * This removes the device from the transport so the given transport will

 * not manage this device any more

 *

 * Returns: 0 for success

 */

static void fcoe_transport_device_remove_all(struct fcoe_transport *t)

{

	struct fcoe_transport_internal *ti, *tmp;

	mutex_lock(&t->devlock);

	list_for_each_entry_safe(ti, tmp, &t->devlist, list) {

		list_del(&ti->list);

		kfree(ti);

	}

	mutex_unlock(&t->devlock);

}

/**

 * fcoe_transport_match() - Use the bus device match function to match the hw

 * @t: The fcoe transport to check

 * @netdev: The netdev to match against

 *

 * This function is used to check if the given transport wants to manage the

 * input netdev. if the transports implements the match function, it will be

 * called, o.w. we just compare the pci vendor and device id.

 *

 * Returns: true for match up

 */

static bool fcoe_transport_match(struct fcoe_transport *t,

				 struct net_device *netdev)

{

	/* match transport by vendor and device id */

	struct pci_dev *pci;

	pci = fcoe_transport_pcidev(netdev);

	if (pci) {

		printk(KERN_DEBUG "fcoe_transport_match:"

		       "%s:%x:%x -- %s:%x:%x\n",

		       t->name, t->vendor, t->device,

		       netdev->name, pci->vendor, pci->device);

		/* if transport supports match */

		if (t->match)

			return t->match(netdev);

		/* else just compare the vendor and device id: pci only */

		return (t->vendor == pci->vendor) && (t->device == pci->device);

	}

	return false;

}

/**

 * fcoe_transport_lookup() - Check if the transport is already registered

 * @t: the transport to be looked up

 *

 * This compares the parent device (pci) vendor and device id

 *

 * Returns: NULL if not found

 *

 * TODO: return default sw transport if no other transport is found

 */

static struct fcoe_transport *

fcoe_transport_lookup(struct net_device *netdev)

{

	struct fcoe_transport *t;

	mutex_lock(&fcoe_transports_lock);

	list_for_each_entry(t, &fcoe_transports, list) {

		if (fcoe_transport_match(t, netdev)) {

			mutex_unlock(&fcoe_transports_lock);

			return t;

		}

	}

	mutex_unlock(&fcoe_transports_lock);

	printk(KERN_DEBUG "fcoe_transport_lookup:"

	       "use default transport for %s\n", netdev->name);

	return fcoe_transport_default();

}

/**

 * fcoe_transport_register() - Adds a fcoe transport to the fcoe transports list

 * @t: ptr to the fcoe transport to be added

 *

 * Returns: 0 for success

 */

int fcoe_transport_register(struct fcoe_transport *t)

{

	struct fcoe_transport *tt;

	/* TODO - add fcoe_transport specific initialization here */

	mutex_lock(&fcoe_transports_lock);

	list_for_each_entry(tt, &fcoe_transports, list) {

		if (tt == t) {

			mutex_unlock(&fcoe_transports_lock);

			return -EEXIST;

		}

	}

	list_add_tail(&t->list, &fcoe_transports);

	mutex_unlock(&fcoe_transports_lock);

	printk(KERN_DEBUG "fcoe_transport_register:%s\n", t->name);

	return 0;

}

EXPORT_SYMBOL_GPL(fcoe_transport_register);

/**

 * fcoe_transport_unregister() - Remove the tranport fro the fcoe transports list

 * @t: ptr to the fcoe transport to be removed

 *

 * Returns: 0 for success

 */

int fcoe_transport_unregister(struct fcoe_transport *t)

{

	struct fcoe_transport *tt, *tmp;

	mutex_lock(&fcoe_transports_lock);

	list_for_each_entry_safe(tt, tmp, &fcoe_transports, list) {

		if (tt == t) {

			list_del(&t->list);

			mutex_unlock(&fcoe_transports_lock);

			fcoe_transport_device_remove_all(t);

			printk(KERN_DEBUG "fcoe_transport_unregister:%s\n",

			       t->name);

			return 0;

		}

	}

	mutex_unlock(&fcoe_transports_lock);

	return -ENODEV;

}

EXPORT_SYMBOL_GPL(fcoe_transport_unregister);

/**

 * fcoe_load_transport_driver() - Load an offload driver by alias name

 * @netdev: the target net device

 *

 * Requests for an offload driver module as the fcoe transport, if fails, it

 * falls back to use the SW HBA (fcoe_sw) as its transport

 *

 * TODO -

 * 	1. supports only PCI device

 * 	2. needs fix for VLAn and bonding

 * 	3. pure hw fcoe hba may not have netdev

 *

 * Returns: 0 for success

 */

int fcoe_load_transport_driver(struct net_device *netdev)

{

	struct pci_dev *pci;

	struct device *dev = netdev->dev.parent;

	if (fcoe_transport_lookup(netdev)) {

		/* load default transport */

		printk(KERN_DEBUG "fcoe: already loaded transport for %s\n",

		       netdev->name);

		return -EEXIST;

	}

	pci = to_pci_dev(dev);

	if (dev->bus != &pci_bus_type) {

		printk(KERN_DEBUG "fcoe: support noly PCI device\n");

		return -ENODEV;

	}

	printk(KERN_DEBUG "fcoe: loading driver fcoe-pci-0x%04x-0x%04x\n",

	       pci->vendor, pci->device);

	return request_module("fcoe-pci-0x%04x-0x%04x",

			      pci->vendor, pci->device);

}

EXPORT_SYMBOL_GPL(fcoe_load_transport_driver);

/**

 * fcoe_transport_attach() - Load transport to fcoe

 * @netdev: the netdev the transport to be attached to

 *

 * This will look for existing offload driver, if not found, it falls back to

 * the default sw hba (fcoe_sw) as its fcoe transport.

 *

 * Returns: 0 for success

 */

int fcoe_transport_attach(struct net_device *netdev)

{

	struct fcoe_transport *t;

	/* find the corresponding transport */

	t = fcoe_transport_lookup(netdev);

	if (!t) {

		printk(KERN_DEBUG "fcoe_transport_attach"

		       ":no transport for %s:use %s\n",

		       netdev->name, t->name);

		return -ENODEV;

	}

	/* add to the transport */

	if (fcoe_transport_device_add(t, netdev)) {

		printk(KERN_DEBUG "fcoe_transport_attach"

		       ":failed to add %s to tramsport %s\n",

		       netdev->name, t->name);

		return -EIO;

	}

	/* transport create function */

	if (t->create)

		t->create(netdev);

	printk(KERN_DEBUG "fcoe_transport_attach:transport %s for %s\n",

	       t->name, netdev->name);

	return 0;

}

EXPORT_SYMBOL_GPL(fcoe_transport_attach);

/**

 * fcoe_transport_release() - Unload transport from fcoe

 * @netdev: the net device on which fcoe is to be released

 *

 * Returns: 0 for success

 */

int fcoe_transport_release(struct net_device *netdev)

{

	struct fcoe_transport *t;

	/* find the corresponding transport */

	t = fcoe_transport_lookup(netdev);

	if (!t) {

		printk(KERN_DEBUG "fcoe_transport_release:"

		       "no transport for %s:use %s\n",

		       netdev->name, t->name);

		return -ENODEV;

	}

	/* remove the device from the transport */

	if (fcoe_transport_device_remove(t, netdev)) {

		printk(KERN_DEBUG "fcoe_transport_release:"

		       "failed to add %s to tramsport %s\n",

		       netdev->name, t->name);

		return -EIO;

	}

	/* transport destroy function */

	if (t->destroy)

		t->destroy(netdev);

	printk(KERN_DEBUG "fcoe_transport_release:"

	       "device %s dettached from transport %s\n",

	       netdev->name, t->name);

	return 0;

}

EXPORT_SYMBOL_GPL(fcoe_transport_release);

/**

 * fcoe_transport_init() - Initializes fcoe transport layer

 *

 * This prepares for the fcoe transport layer

 *

 * Returns: none

 */

int __init fcoe_transport_init(void)

{

	INIT_LIST_HEAD(&fcoe_transports);

	mutex_init(&fcoe_transports_lock);

	return 0;

}

/**

 * fcoe_transport_exit() - Cleans up the fcoe transport layer

 *

 * This cleans up the fcoe transport layer. removing any transport on the list,

 * note that the transport destroy func is not called here.

 *

 * Returns: none

 */

int __exit fcoe_transport_exit(void)

{

	struct fcoe_transport *t, *tmp;

	mutex_lock(&fcoe_transports_lock);

	list_for_each_entry_safe(t, tmp, &fcoe_transports, list) {

		list_del(&t->list);

		mutex_unlock(&fcoe_transports_lock);

		fcoe_transport_device_remove_all(t);

		mutex_lock(&fcoe_transports_lock);

	}

	mutex_unlock(&fcoe_transports_lock);

	return 0;

}

#ifndef FC_TRANSPORT_FCOE_H

#define FC_TRANSPORT_FCOE_H

#include <linux/device.h>

#include <linux/netdevice.h>

#include <scsi/scsi_host.h>

#include <scsi/libfc.h>

/**

 * struct fcoe_transport - FCoE transport struct for generic transport

 * for Ethernet devices as well as pure HBAs

 *

 * @name: name for thsi transport

 * @bus: physical bus type (pci_bus_type)

 * @driver: physical bus driver for network device

 * @create: entry create function

 * @destroy: exit destroy function

 * @list: list of transports

 */

struct fcoe_transport {

	char *name;

	unsigned short vendor;

	unsigned short device;

	struct bus_type *bus;

	struct device_driver *driver;

	int (*create)(struct net_device *device);

	int (*destroy)(struct net_device *device);

	bool (*match)(struct net_device *device);

	struct list_head list;

	struct list_head devlist;

	struct mutex devlock;

};

/**

 * MODULE_ALIAS_FCOE_PCI

 *

 * some care must be taken with this, vendor and device MUST be a hex value

 * preceded with 0x and with letters in lower case (0x12ab, not 0x12AB or 12AB)

 */

#define MODULE_ALIAS_FCOE_PCI(vendor, device) \

	MODULE_ALIAS("fcoe-pci-" __stringify(vendor) "-" __stringify(device))

/* exported funcs */

int fcoe_transport_attach(struct net_device *netdev);

int fcoe_transport_release(struct net_device *netdev);

int fcoe_transport_register(struct fcoe_transport *t);

int fcoe_transport_unregister(struct fcoe_transport *t);

int fcoe_load_transport_driver(struct net_device *netdev);

int __init fcoe_transport_init(void);

int __exit fcoe_transport_exit(void);

/* fcow_sw is the default transport */

extern struct fcoe_transport fcoe_sw_transport;

#endif /* FC_TRANSPORT_FCOE_H */