i386/linux/linux-2.3.21/include/net/dn_nsp.h

   1 #ifndef _NET_DN_NSP_H
   2 #define _NET_DN_NSP_H
   3 /******************************************************************************
   4     (c) 1995-1998 E.M. Serrat           emserrat@geocities.com
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15 *******************************************************************************/
  16 /* dn_nsp.c functions prototyping */
  17
  18 extern void dn_nsp_send_data_ack(struct sock *sk);
  19 extern void dn_nsp_send_oth_ack(struct sock *sk);
  20 extern void dn_nsp_delayed_ack(struct sock *sk);
  21 extern void dn_send_conn_ack(struct sock *sk);
  22 extern void dn_send_conn_conf(struct sock *sk);
  23 extern void dn_send_disc(struct sock *sk, unsigned char type, unsigned short reason);
  24 extern void dn_nsp_send_lnk(struct sock *sk, unsigned short flags);
  25 extern void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
  26
  27 extern void dn_nsp_output(struct sock *sk);
  28 extern int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum);
  29 extern void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, int oob);
  30 extern unsigned long dn_nsp_persist(struct sock *sk);
  31 extern int dn_nsp_xmit_timeout(struct sock *sk);
  32
  33 extern int dn_nsp_rx(struct sk_buff *);
  34 extern int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
  35
  36 extern struct sk_buff *dn_alloc_skb(struct sock *sk, int size, int pri);
  37 extern struct sk_buff *dn_alloc_send_skb(struct sock *sk, int *size, int noblock, int *err);
  38
  39 #define NSP_REASON_NR 1
  40 #define NSP_REASON_DC 42
  41 #define NSP_REASON_NL 41
  42
  43 #define NSP_DISCINIT 0x38
  44 #define NSP_DISCCONF 0x48
  45
  46 /*------------------------- NSP - messages ------------------------------*/
  47 /* Data Messages */
  48 /*---------------*/
  49
  50 /* Data Messages    (data segment/interrupt/link service)               */
  51
  52         struct nsp_data_seg_msg
  53         {
  54                 unsigned char   msgflg          __attribute__((packed));
  55                 unsigned short  dstaddr         __attribute__((packed));
  56                 unsigned short  srcaddr         __attribute__((packed));
  57         };
  58
  59         struct nsp_data_opt_msg
  60         {
  61                 unsigned short  acknum          __attribute__((packed));
  62                 unsigned short  segnum          __attribute__((packed));
  63                 unsigned short  lsflgs          __attribute__((packed));
  64         };
  65
  66         struct nsp_data_opt_msg1
  67         {
  68                 unsigned short  acknum          __attribute__((packed));
  69                 unsigned short  segnum          __attribute__((packed));
  70         };
  71
  72 /* Acknowledgment Messages */
  73 /*-------------------------*/
  74
  75 /* Acknowledgment Messages (data/other data)                             */
  76
  77         struct  nsp_data_ack_msg
  78         {
  79                 unsigned char   msgflg          __attribute__((packed));
  80                 unsigned short  dstaddr         __attribute__((packed));
  81                 unsigned short  srcaddr         __attribute__((packed));
  82                 unsigned short  acknum          __attribute__((packed));
  83         };
  84
  85 /* Connect Acknowledgment Message */
  86
  87         struct  nsp_conn_ack_msg
  88         {
  89                 unsigned char   msgflg          __attribute__((packed));
  90                 unsigned short  dstaddr         __attribute__((packed));
  91         };
  92
  93 /* Control Messages */
  94 /*------------------*/
  95
  96 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
  97
  98         struct  nsp_conn_init_msg
  99         {
 100                 unsigned char   msgflg          __attribute__((packed));
 101 #define         NSP_CI          0x18            /* Connect Initiate     */
 102 #define         NSP_RCI         0x68            /* Retrans. Conn Init   */
 103                 unsigned short  dstaddr         __attribute__((packed));
 104                 unsigned short  srcaddr         __attribute__((packed));
 105                 unsigned char   services        __attribute__((packed));
 106 #define         NSP_FC_NONE     0x00            /* Flow Control None    */
 107 #define         NSP_FC_SRC      0x04            /* Seg Req. Count       */
 108 #define         NSP_FC_SCMC     0x08            /* Sess. Control Mess   */
 109                 unsigned char   info            __attribute__((packed));
 110                 unsigned short  segsize         __attribute__((packed));
 111         };
 112
 113 /* Disconnect Initiate/Disconnect Confirm */
 114
 115         struct  nsp_disconn_init_msg
 116         {
 117                 unsigned char   msgflg          __attribute__((packed));
 118                 unsigned short  dstaddr         __attribute__((packed));
 119                 unsigned short  srcaddr         __attribute__((packed));
 120                 unsigned short  reason          __attribute__((packed));
 121         };
 122
 123
 124 /*------------------------- SCP - messages ------------------------------*/
 125
 126         struct  srcobj_fmt
 127         {
 128                 char            format          __attribute__((packed));
 129                 unsigned char   task            __attribute__((packed));
 130                 unsigned short  grpcode         __attribute__((packed));
 131                 unsigned short  usrcode         __attribute__((packed));
 132                 char            dlen            __attribute__((packed));
 133         };
 134
 135 /*
 136  * A collection of functions for manipulating the sequence
 137  * numbers used in NSP. Similar in operation to the functions
 138  * of the same name in TCP.
 139  */
 140 static __inline__ int before(unsigned short seq1, unsigned short seq2)
 141 {
 142         seq1 &= 0x0fff;
 143         seq2 &= 0x0fff;
 144
 145         return (int)((seq1 - seq2) & 0x0fff) > 2048;
 146 }
 147
 148
 149 static __inline__ int after(unsigned short seq1, unsigned short seq2)
 150 {
 151         seq1 &= 0x0fff;
 152         seq2 &= 0x0fff;
 153
 154         return (int)((seq2 - seq1) & 0x0fff) > 2048;
 155 }
 156
 157 static __inline__ int equal(unsigned short seq1, unsigned short seq2)
 158 {
 159         return ((seq1 ^ seq2) & 0x0fff) == 0;
 160 }
 161
 162 static __inline__ int before_or_equal(unsigned short seq1, unsigned short seq2)
 163 {
 164         return (before(seq1, seq2) || equal(seq1, seq2));
 165 }
 166
 167 static __inline__ void seq_add(unsigned short *seq, unsigned short off)
 168 {
 169         *seq += off;
 170         *seq &= 0x0fff;
 171 }
 172
 173 static __inline__ int seq_next(unsigned short seq1, unsigned short seq2)
 174 {
 175         return (((seq2&0x0fff) - (seq1&0x0fff)) == 1);
 176 }
 177
 178 /*
 179  * Can we delay the ack ?
 180  */
 181 static __inline__ int sendack(unsigned short seq)
 182 {
 183         return (int)((seq & 0x1000) ? 0 : 1);
 184 }
 185
 186 /*
 187  * Is socket congested ?
 188  */
 189 static __inline__ int dn_congested(struct sock *sk)
 190 {
 191         return atomic_read(&sk->rmem_alloc) > (sk->rcvbuf >> 1);
 192 }
 193
 194 #endif /* _NET_DN_NSP_H */