diff options
Diffstat (limited to 'drivers/scsi/fcoe/fc_transport_fcoe.c')
| -rw-r--r-- | drivers/scsi/fcoe/fc_transport_fcoe.c | 446 |
1 files changed, 446 insertions, 0 deletions
diff --git a/drivers/scsi/fcoe/fc_transport_fcoe.c b/drivers/scsi/fcoe/fc_transport_fcoe.c new file mode 100644 index 00000000000..bf7fe6fc082 --- /dev/null +++ b/drivers/scsi/fcoe/fc_transport_fcoe.c @@ -0,0 +1,446 @@ +/* + * 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 - find out netdev is managed by the + * transport + * 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 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 + * @netdev: + * + * This function is used to check if the givne 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; +} |