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, int gfp);
  23 extern void dn_nsp_send_disc(struct sock *sk, unsigned char type,
  24                                 unsigned short reason, int gfp);
  25 extern void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
  26                                 unsigned short reason);
  27 extern void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
  28 extern void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
  29
  30 extern void dn_nsp_output(struct sock *sk);
  31 extern int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum);
  32 extern void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, int gfp, int oob);
  33 extern unsigned long dn_nsp_persist(struct sock *sk);
  34 extern int dn_nsp_xmit_timeout(struct sock *sk);
  35
  36 extern int dn_nsp_rx(struct sk_buff *);
  37 extern int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
  38
  39 extern struct sk_buff *dn_alloc_skb(struct sock *sk, int size, int pri);
  40 extern struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock, long timeo, int *err);
  41
  42 #define NSP_REASON_OK 0         /* No error */
  43 #define NSP_REASON_NR 1         /* No resources */
  44 #define NSP_REASON_UN 2         /* Unrecognised node name */
  45 #define NSP_REASON_SD 3         /* Node shutting down */
  46 #define NSP_REASON_ID 4         /* Invalid destination end user */
  47 #define NSP_REASON_ER 5         /* End user lacks resources */
  48 #define NSP_REASON_OB 6         /* Object too busy */
  49 #define NSP_REASON_US 7         /* Unspecified error */
  50 #define NSP_REASON_TP 8         /* Third-Party abort */
  51 #define NSP_REASON_EA 9         /* End user has aborted the link */
  52 #define NSP_REASON_IF 10        /* Invalid node name format */
  53 #define NSP_REASON_LS 11        /* Local node shutdown */
  54 #define NSP_REASON_LL 32        /* Node lacks logical-link resources */
  55 #define NSP_REASON_LE 33        /* End user lacks logical-link resources */
  56 #define NSP_REASON_UR 34        /* Unacceptable RQSTRID or PASSWORD field */
  57 #define NSP_REASON_UA 36        /* Unacceptable ACCOUNT field */
  58 #define NSP_REASON_TM 38        /* End user timed out logical link */
  59 #define NSP_REASON_NU 39        /* Node unreachable */
  60 #define NSP_REASON_NL 41        /* No-link message */
  61 #define NSP_REASON_DC 42        /* Disconnect confirm */
  62 #define NSP_REASON_IO 43        /* Image data field overflow */
  63
  64 #define NSP_DISCINIT 0x38
  65 #define NSP_DISCCONF 0x48
  66
  67 /*------------------------- NSP - messages ------------------------------*/
  68 /* Data Messages */
  69 /*---------------*/
  70
  71 /* Data Messages    (data segment/interrupt/link service)               */
  72
  73 struct nsp_data_seg_msg
  74 {
  75         unsigned char   msgflg          __attribute__((packed));
  76         unsigned short  dstaddr         __attribute__((packed));
  77         unsigned short  srcaddr         __attribute__((packed));
  78 };
  79
  80 struct nsp_data_opt_msg
  81 {
  82         unsigned short  acknum          __attribute__((packed));
  83         unsigned short  segnum          __attribute__((packed));
  84         unsigned short  lsflgs          __attribute__((packed));
  85 };
  86
  87 struct nsp_data_opt_msg1
  88 {
  89         unsigned short  acknum          __attribute__((packed));
  90         unsigned short  segnum          __attribute__((packed));
  91 };
  92
  93
  94 /* Acknowledgment Message (data/other data)                             */
  95 struct nsp_data_ack_msg
  96 {
  97         unsigned char   msgflg          __attribute__((packed));
  98         unsigned short  dstaddr         __attribute__((packed));
  99         unsigned short  srcaddr         __attribute__((packed));
 100         unsigned short  acknum          __attribute__((packed));
 101 };
 102
 103 /* Connect Acknowledgment Message */
 104 struct  nsp_conn_ack_msg
 105 {
 106         unsigned char   msgflg          __attribute__((packed));
 107         unsigned short  dstaddr         __attribute__((packed));
 108 };
 109
 110
 111 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
 112 struct  nsp_conn_init_msg
 113 {
 114         unsigned char   msgflg          __attribute__((packed));
 115 #define NSP_CI      0x18            /* Connect Initiate     */
 116 #define NSP_RCI     0x68            /* Retrans. Conn Init   */
 117         unsigned short  dstaddr         __attribute__((packed));
 118         unsigned short  srcaddr         __attribute__((packed));
 119         unsigned char   services        __attribute__((packed));
 120 #define NSP_FC_NONE   0x00            /* Flow Control None    */
 121 #define NSP_FC_SRC    0x04            /* Seg Req. Count       */
 122 #define NSP_FC_SCMC   0x08            /* Sess. Control Mess   */
 123 #define NSP_FC_MASK   0x0c            /* FC type mask         */
 124         unsigned char   info            __attribute__((packed));
 125         unsigned short  segsize         __attribute__((packed));
 126 };
 127
 128 /* Disconnect Initiate/Disconnect Confirm */
 129 struct  nsp_disconn_init_msg
 130 {
 131         unsigned char   msgflg          __attribute__((packed));
 132         unsigned short  dstaddr         __attribute__((packed));
 133         unsigned short  srcaddr         __attribute__((packed));
 134         unsigned short  reason          __attribute__((packed));
 135 };
 136
 137
 138
 139 struct  srcobj_fmt
 140 {
 141         char            format          __attribute__((packed));
 142         unsigned char   task            __attribute__((packed));
 143         unsigned short  grpcode         __attribute__((packed));
 144         unsigned short  usrcode         __attribute__((packed));
 145         char            dlen            __attribute__((packed));
 146 };
 147
 148 /*
 149  * A collection of functions for manipulating the sequence
 150  * numbers used in NSP. Similar in operation to the functions
 151  * of the same name in TCP.
 152  */
 153 static __inline__ int dn_before(unsigned short seq1, unsigned short seq2)
 154 {
 155         seq1 &= 0x0fff;
 156         seq2 &= 0x0fff;
 157
 158         return (int)((seq1 - seq2) & 0x0fff) > 2048;
 159 }
 160
 161
 162 static __inline__ int dn_after(unsigned short seq1, unsigned short seq2)
 163 {
 164         seq1 &= 0x0fff;
 165         seq2 &= 0x0fff;
 166
 167         return (int)((seq2 - seq1) & 0x0fff) > 2048;
 168 }
 169
 170 static __inline__ int dn_equal(unsigned short seq1, unsigned short seq2)
 171 {
 172         return ((seq1 ^ seq2) & 0x0fff) == 0;
 173 }
 174
 175 static __inline__ int dn_before_or_equal(unsigned short seq1, unsigned short seq2)
 176 {
 177         return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
 178 }
 179
 180 static __inline__ void seq_add(unsigned short *seq, unsigned short off)
 181 {
 182         (*seq) += off;
 183         (*seq) &= 0x0fff;
 184 }
 185
 186 static __inline__ int seq_next(unsigned short seq1, unsigned short seq2)
 187 {
 188         return dn_equal(seq1 + 1, seq2);
 189 }
 190
 191 /*
 192  * Can we delay the ack ?
 193  */
 194 static __inline__ int sendack(unsigned short seq)
 195 {
 196         return (int)((seq & 0x1000) ? 0 : 1);
 197 }
 198
 199 /*
 200  * Is socket congested ?
 201  */
 202 static __inline__ int dn_congested(struct sock *sk)
 203 {
 204         return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
 205 }
 206
 207 #define DN_MAX_NSP_DATA_HEADER (11)
 208
 209 #endif /* _NET_DN_NSP_H */