/*
   * 	connector.h
   * 
   * 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
   * All rights reserved.
   * 
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  #ifndef __CONNECTOR_H
  #define __CONNECTOR_H

  #include <linux/types.h>

  /*
   * Process Events connector unique ids -- used for message routing
   */
  #define CN_IDX_PROC			0x1
  #define CN_VAL_PROC			0x1

  #define CN_IDX_CIFS			0x2
  #define CN_VAL_CIFS                     0x1

  #define CN_W1_IDX			0x3	/* w1 communication */
  #define CN_W1_VAL			0x1

  #define CN_IDX_V86D			0x4
  #define CN_VAL_V86D_UVESAFB		0x1

  #define CN_IDX_BB			0x5	/* BlackBoard, from the TSP GPL sampling framework */

  #define CN_DST_IDX			0x6
  #define CN_DST_VAL			0x1

  #define CN_IDX_DM			0x7	/* Device Mapper */
  #define CN_VAL_DM_USERSPACE_LOG		0x1

  #define CN_IDX_DRBD			0x8
  #define CN_VAL_DRBD			0x1

  #define CN_NETLINK_USERS		8

  
  /*
   * Maximum connector's message size.
   */

  #define CONNECTOR_MAX_MSG_SIZE		16384

  
  /*
   * idx and val are unique identifiers which 
   * are used for message routing and 
   * must be registered in connector.h for in-kernel usage.
   */
  
  struct cb_id {
  	__u32 idx;
  	__u32 val;
  };
  
  struct cn_msg {
  	struct cb_id id;
  
  	__u32 seq;
  	__u32 ack;
  
  	__u16 len;		/* Length of the following data */
  	__u16 flags;
  	__u8 data[0];
  };

  #ifdef __KERNEL__
  
  #include <asm/atomic.h>
  
  #include <linux/list.h>
  #include <linux/workqueue.h>
  
  #include <net/sock.h>
  
  #define CN_CBQ_NAMELEN		32
  
  struct cn_queue_dev {
  	atomic_t refcnt;
  	unsigned char name[CN_CBQ_NAMELEN];
  
  	struct workqueue_struct *cn_queue;

  	/* Sent to kevent to create cn_queue only when needed */
  	struct work_struct wq_creation;
  	/* Tell if the wq_creation job is pending/completed */
  	atomic_t wq_requested;
  	/* Wait for cn_queue to be created */
  	wait_queue_head_t wq_created;

  
  	struct list_head queue_list;
  	spinlock_t queue_lock;

  	struct sock *nls;
  };

  struct cn_callback_id {

  	unsigned char name[CN_CBQ_NAMELEN];

  	struct cb_id id;

  };
  
  struct cn_callback_data {

  	struct sk_buff *skb;

  	void (*callback) (struct cn_msg *, struct netlink_skb_parms *);

  
  	void *free;

  };
  
  struct cn_callback_entry {
  	struct list_head callback_entry;

  	struct work_struct work;

  	struct cn_queue_dev *pdev;

  	struct cn_callback_id id;
  	struct cn_callback_data data;

  	u32 seq, group;

  };

  struct cn_dev {
  	struct cb_id id;
  
  	u32 seq, groups;
  	struct sock *nls;

  	void (*input) (struct sk_buff *skb);

  
  	struct cn_queue_dev *cbdev;
  };

  int cn_add_callback(struct cb_id *, char *, void (*callback) (struct cn_msg *, struct netlink_skb_parms *));

  void cn_del_callback(struct cb_id *);

  int cn_netlink_send(struct cn_msg *, u32, gfp_t);

  int cn_queue_add_callback(struct cn_queue_dev *dev, char *name, struct cb_id *id, void (*callback)(struct cn_msg *, struct netlink_skb_parms *));

  void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id);

  int queue_cn_work(struct cn_callback_entry *cbq, struct work_struct *work);

  struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *);
  void cn_queue_free_dev(struct cn_queue_dev *dev);
  
  int cn_cb_equal(struct cb_id *, struct cb_id *);

  void cn_queue_wrapper(struct work_struct *work);

  #endif				/* __KERNEL__ */
  #endif				/* __CONNECTOR_H */