/*
* 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);
mutex_init(&t->devlock);
INIT_LIST_HEAD(&t->devlist);
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;
}
