path: root/drivers/scsi/fcoe/libfcoe.c

/*
 * Copyright (c) 2008-2009 Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2009 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/spinlock.h>
#include <linux/timer.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/errno.h>
#include <linux/bitops.h>
#include <net/rtnetlink.h>

#include <scsi/fc/fc_els.h>
#include <scsi/fc/fc_fs.h>
#include <scsi/fc/fc_fip.h>
#include <scsi/fc/fc_encaps.h>
#include <scsi/fc/fc_fcoe.h>

#include <scsi/libfc.h>
#include <scsi/libfcoe.h>

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

#define	FCOE_CTLR_MIN_FKA	500		/* min keep alive (mS) */
#define	FCOE_CTLR_DEF_FKA	FIP_DEF_FKA	/* default keep alive (mS) */

static void fcoe_ctlr_timeout(unsigned long);
static void fcoe_ctlr_link_work(struct work_struct *);
static void fcoe_ctlr_recv_work(struct work_struct *);

static u8 fcoe_all_fcfs[ETH_ALEN] = FIP_ALL_FCF_MACS;

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");

#define LIBFCOE_LOGGING     0x01 /* General logging, not categorized */
#define LIBFCOE_FIP_LOGGING 0x02 /* FIP logging */

#define LIBFCOE_CHECK_LOGGING(LEVEL, CMD)				\
do {                                                            	\
	if (unlikely(libfcoe_debug_logging & LEVEL))			\
		do {							\
			CMD;						\
		} while (0);						\
} while (0)

#define LIBFCOE_DBG(fmt, args...)					\
	LIBFCOE_CHECK_LOGGING(LIBFCOE_LOGGING,				\
			      printk(KERN_INFO "libfcoe: " fmt, ##args);)

#define LIBFCOE_FIP_DBG(fmt, args...)					\
	LIBFCOE_CHECK_LOGGING(LIBFCOE_FIP_LOGGING,			\
			      printk(KERN_INFO "fip: " fmt, ##args);)

/*
 * Return non-zero if FCF fcoe_size has been validated.
 */
static inline int fcoe_ctlr_mtu_valid(const struct fcoe_fcf *fcf)
{
	return (fcf->flags & FIP_FL_SOL) != 0;
}

/*
 * Return non-zero if the FCF is usable.
 */
static inline int fcoe_ctlr_fcf_usable(struct fcoe_fcf *fcf)
{
	u16 flags = FIP_FL_SOL | FIP_FL_AVAIL;

	return (fcf->flags & flags) == flags;
}

/**
 * fcoe_ctlr_init() - Initialize the FCoE Controller instance.
 * @fip:	FCoE controller.
 */
void fcoe_ctlr_init(struct fcoe_ctlr *fip)
{
	fip->state = FIP_ST_LINK_WAIT;
	INIT_LIST_HEAD(&fip->fcfs);
	spin_lock_init(&fip->lock);
	fip->flogi_oxid = FC_XID_UNKNOWN;
	setup_timer(&fip->timer, fcoe_ctlr_timeout, (unsigned long)fip);
	INIT_WORK(&fip->link_work, fcoe_ctlr_link_work);
	INIT_WORK(&fip->recv_work, fcoe_ctlr_recv_work);
	skb_queue_head_init(&fip->fip_recv_list);
}
EXPORT_SYMBOL(fcoe_ctlr_init);

/**
 * fcoe_ctlr_reset_fcfs() - Reset and free all FCFs for a controller.
 * @fip:	FCoE controller.
 *
 * Called with &fcoe_ctlr lock held.
 */
static void fcoe_ctlr_reset_fcfs(struct fcoe_ctlr *fip)
{
	struct fcoe_fcf *fcf;
	struct fcoe_fcf *next;

	fip->sel_fcf = NULL;
	list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
		list_del(&fcf->list);
		kfree(fcf);
	}
	fip->fcf_count = 0;
	fip->sel_time = 0;
}

/**
 * fcoe_ctlr_destroy() - Disable and tear-down the FCoE controller.
 * @fip:	FCoE controller.
 *
 * This is called by FCoE drivers before freeing the &fcoe_ctlr.
 *
 * The receive handler will have been deleted before this to guarantee
 * that no more recv_work will be scheduled.
 *
 * The timer routine will simply return once we set FIP_ST_DISABLED.
 * This guarantees that no further timeouts or work will be scheduled.
 */
void fcoe_ctlr_destroy(struct fcoe_ctlr *fip)
{
	cancel_work_sync(&fip->recv_work);
	spin_lock_bh(&fip->fip_recv_list.lock);
	__skb_queue_purge(&fip->fip_recv_list);
	spin_unlock_bh(&fip->fip_recv_list.lock);

	spin_lock_bh(&fip->lock);
	fip->state = FIP_ST_DISABLED;
	fcoe_ctlr_reset_fcfs(