kernel-fxtec-pro1x/drivers/scsi/fcoe/fcoe.h
Chris Leech 2e70e24151 [SCSI] fcoe: Fix module ref count bug by adding NETDEV UNREGISTER handling
Fixes reference counting on fcoe_instance and net_device, and adds
NETDEV_UNREGISTER notifier handling so that you can unload network drivers.
FCoE no longer increments the module use count for the network driver.

On an NETDEV_UNREGISTER event, destroying the FCoE instance is deferred to a
workqueue context to avoid RTNL deadlocks.

Based in part by an earlier patch from John Fastabend

John's patch description:
Currently, the netdev module ref count is not decremented with module_put()
when the module is unloaded while fcoe instances are present. To fix this
removed reference count on netdev module completely and added functionality to
netdev event handling for NETDEV_UNREGISTER events.

This allows fcoe to remove devices cleanly when the netdev module is unloaded
so we no longer need to hold a reference count for the netdev module.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-09-10 12:07:38 -05:00

110 lines
3.1 KiB
C

/*
* 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
*/
#ifndef _FCOE_H_
#define _FCOE_H_
#include <linux/skbuff.h>
#include <linux/kthread.h>
#define FCOE_MAX_QUEUE_DEPTH 256
#define FCOE_LOW_QUEUE_DEPTH 32
#define FCOE_WORD_TO_BYTE 4
#define FCOE_VERSION "0.1"
#define FCOE_NAME "fcoe"
#define FCOE_VENDOR "Open-FCoE.org"
#define FCOE_MAX_LUN 255
#define FCOE_MAX_FCP_TARGET 256
#define FCOE_MAX_OUTSTANDING_COMMANDS 1024
#define FCOE_MIN_XID 0x0000 /* the min xid supported by fcoe_sw */
#define FCOE_MAX_XID 0x0FFF /* the max xid supported by fcoe_sw */
unsigned int fcoe_debug_logging;
module_param_named(debug_logging, fcoe_debug_logging, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
#define FCOE_LOGGING 0x01 /* General logging, not categorized */
#define FCOE_NETDEV_LOGGING 0x02 /* Netdevice logging */
#define FCOE_CHECK_LOGGING(LEVEL, CMD) \
do { \
if (unlikely(fcoe_debug_logging & LEVEL)) \
do { \
CMD; \
} while (0); \
} while (0)
#define FCOE_DBG(fmt, args...) \
FCOE_CHECK_LOGGING(FCOE_LOGGING, \
printk(KERN_INFO "fcoe: " fmt, ##args);)
#define FCOE_NETDEV_DBG(netdev, fmt, args...) \
FCOE_CHECK_LOGGING(FCOE_NETDEV_LOGGING, \
printk(KERN_INFO "fcoe: %s: " fmt, \
netdev->name, ##args);)
/*
* this percpu struct for fcoe
*/
struct fcoe_percpu_s {
struct task_struct *thread;
struct sk_buff_head fcoe_rx_list;
struct page *crc_eof_page;
int crc_eof_offset;
};
/*
* an FCoE interface, 1:1 with netdev
*/
struct fcoe_interface {
struct list_head list;
struct net_device *netdev;
struct packet_type fcoe_packet_type;
struct packet_type fip_packet_type;
struct fcoe_ctlr ctlr;
struct fc_exch_mgr *oem; /* offload exchange manager */
struct kref kref;
};
/*
* the FCoE private structure that's allocated along with the
* Scsi_Host and libfc fc_lport structures
*/
struct fcoe_port {
struct fcoe_interface *fcoe;
struct fc_lport *lport;
struct sk_buff_head fcoe_pending_queue;
u8 fcoe_pending_queue_active;
struct timer_list timer; /* queue timer */
struct work_struct destroy_work; /* to prevent rtnl deadlocks */
};
#define fcoe_from_ctlr(fip) container_of(fip, struct fcoe_interface, ctlr)
static inline struct net_device *fcoe_netdev(const struct fc_lport *lp)
{
return ((struct fcoe_port *)lport_priv(lp))->fcoe->netdev;
}
#endif /* _FCOE_H_ */