concap.h 3.69 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10
/* $Id: concap.h,v 1.3.2.2 2004/01/12 23:08:35 keil Exp $
 *
 * Copyright 1997 by Henner Eisen <eis@baty.hanse.de>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 */

#ifndef _LINUX_CONCAP_H
#define _LINUX_CONCAP_H
11

Linus Torvalds's avatar
Linus Torvalds committed
12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112
#include <linux/skbuff.h>
#include <linux/netdevice.h>

/* Stuff to support encapsulation protocols genericly. The encapsulation
   protocol is processed at the uppermost layer of the network interface.

   Based on a ideas developed in a 'synchronous device' thread in the
   linux-x25 mailing list contributed by Alan Cox, Thomasz Motylewski
   and Jonathan Naylor.

   For more documetation on this refer to Documentation/isdn/README.concap
*/

struct concap_proto_ops;
struct concap_device_ops;

/* this manages all data needed by the encapsulation protocol
 */
struct concap_proto{
	struct net_device *net_dev;	/* net device using our service  */
	struct concap_device_ops *dops;	/* callbacks provided by device */
 	struct concap_proto_ops  *pops;	/* callbacks provided by us */
 	spinlock_t lock;
	int flags;
	void *proto_data;		/* protocol specific private data, to
					   be accessed via *pops methods only*/
	/*
	  :
	  whatever 
	  :
	  */
};

/* Operations to be supported by the net device. Called by the encapsulation
 * protocol entity. No receive method is offered because the encapsulation
 * protocol directly calls netif_rx().
 */
struct concap_device_ops{

	/* to request data is submitted by device*/ 
	int (*data_req)(struct concap_proto *, struct sk_buff *);

	/* Control methods must be set to NULL by devices which do not
	   support connection control.*/
	/* to request a connection is set up */ 
	int (*connect_req)(struct concap_proto *);

	/* to request a connection is released */
	int (*disconn_req)(struct concap_proto *);	
};

/* Operations to be supported by the encapsulation protocol. Called by
 * device driver.
 */
struct concap_proto_ops{

	/* create a new encapsulation protocol instance of same type */
	struct concap_proto *  (*proto_new) (void);

	/* delete encapsulation protocol instance and free all its resources.
	   cprot may no loger be referenced after calling this */
	void (*proto_del)(struct concap_proto *cprot);

	/* initialize the protocol's data. To be called at interface startup
	   or when the device driver resets the interface. All services of the
	   encapsulation protocol may be used after this*/
	int (*restart)(struct concap_proto *cprot, 
		       struct net_device *ndev,
		       struct concap_device_ops *dops);

	/* inactivate an encapsulation protocol instance. The encapsulation
	   protocol may not call any *dops methods after this. */
	int (*close)(struct concap_proto *cprot);

	/* process a frame handed down to us by upper layer */
	int (*encap_and_xmit)(struct concap_proto *cprot, struct sk_buff *skb);

	/* to be called for each data entity received from lower layer*/ 
	int (*data_ind)(struct concap_proto *cprot, struct sk_buff *skb);

	/* to be called when a connection was set up/down.
	   Protocols that don't process these primitives might fill in
	   dummy methods here */
	int (*connect_ind)(struct concap_proto *cprot);
	int (*disconn_ind)(struct concap_proto *cprot);
  /*
    Some network device support functions, like net_header(), rebuild_header(),
    and others, that depend solely on the encapsulation protocol, might
    be provided here, too. The net device would just fill them in its
    corresponding fields when it is opened.
    */
};

/* dummy restart/close/connect/reset/disconn methods
 */
extern int concap_nop(struct concap_proto *cprot); 

/* dummy submit method
 */
extern int concap_drop_skb(struct concap_proto *cprot, struct sk_buff *skb);
#endif