1 /* $Id: concap.h,v 1.2.8.1 2001/09/23 22:25:05 kai Exp $ 2 * 3 * Copyright 1997 by Henner Eisen <eis@baty.hanse.de> 4 * 5 * This software may be used and distributed according to the terms 6 * of the GNU General Public License, incorporated herein by reference. 7 */ 8 9 #ifndef _LINUX_CONCAP_H 10 #define _LINUX_CONCAP_H 11 #ifdef __KERNEL__ 12 #include <linux/skbuff.h> 13 #include <linux/netdevice.h> 14 15 /* Stuff to support encapsulation protocols genericly. The encapsulation 16 protocol is processed at the uppermost layer of the network interface. 17 18 Based on a ideas developed in a 'synchronous device' thread in the 19 linux-x25 mailing list contributed by Alan Cox, Thomasz Motylewski 20 and Jonathan Naylor. 21 22 For more documetation on this refer to Documentation/isdn/README.concap 23 */ 24 25 struct concap_proto_ops; 26 struct concap_device_ops; 27 28 /* this manages all data needed by the encapsulation protocol 29 */ 30 struct concap_proto{ 31 struct net_device *net_dev; /* net device using our service */ 32 struct concap_device_ops *dops; /* callbacks provided by device */ 33 struct concap_proto_ops *pops; /* callbacks provided by us */ 34 int flags; 35 void *proto_data; /* protocol specific private data, to 36 be accessed via *pops methods only*/ 37 /* 38 : 39 whatever 40 : 41 */ 42 }; 43 44 /* Operations to be supported by the net device. Called by the encapsulation 45 * protocol entity. No receive method is offered because the encapsulation 46 * protocol directly calls netif_rx(). 47 */ 48 struct concap_device_ops{ 49 50 /* to request data is submitted by device*/ 51 int (*data_req)(struct concap_proto *, struct sk_buff *); 52 53 /* Control methods must be set to NULL by devices which do not 54 support connection control.*/ 55 /* to request a connection is set up */ 56 int (*connect_req)(struct concap_proto *); 57 58 /* to request a connection is released */ 59 int (*disconn_req)(struct concap_proto *); 60 }; 61 62 /* Operations to be supported by the encapsulation protocol. Called by 63 * device driver. 64 */ 65 struct concap_proto_ops{ 66 67 /* create a new encapsulation protocol instance of same type */ 68 struct concap_proto * (*proto_new) (void); 69 70 /* delete encapsulation protocol instance and free all its resources. 71 cprot may no loger be referenced after calling this */ 72 void (*proto_del)(struct concap_proto *cprot); 73 74 /* initialize the protocol's data. To be called at interface startup 75 or when the device driver resets the interface. All services of the 76 encapsulation protocol may be used after this*/ 77 int (*restart)(struct concap_proto *cprot, 78 struct net_device *ndev, 79 struct concap_device_ops *dops); 80 81 /* inactivate an encapsulation protocol instance. The encapsulation 82 protocol may not call any *dops methods after this. */ 83 int (*close)(struct concap_proto *cprot); 84 85 /* process a frame handed down to us by upper layer */ 86 int (*encap_and_xmit)(struct concap_proto *cprot, struct sk_buff *skb); 87 88 /* to be called for each data entity received from lower layer*/ 89 int (*data_ind)(struct concap_proto *cprot, struct sk_buff *skb); 90 91 /* to be called when a connection was set up/down. 92 Protocols that don't process these primitives might fill in 93 dummy methods here */ 94 int (*connect_ind)(struct concap_proto *cprot); 95 int (*disconn_ind)(struct concap_proto *cprot); 96 /* 97 Some network device support functions, like net_header(), rebuild_header(), 98 and others, that depend solely on the encapsulation protocol, might 99 be provided here, too. The net device would just fill them in its 100 corresponding fields when it is opened. 101 */ 102 }; 103 104 /* dummy restart/close/connect/reset/disconn methods 105 */ 106 extern int concap_nop(struct concap_proto *cprot); 107 108 /* dummy submit method 109 */ 110 extern int concap_drop_skb(struct concap_proto *cprot, struct sk_buff *skb); 111 #endif 112 #endif 113