include/net/irda/irttp.h

   1 /*********************************************************************
   2  *
   3  * Filename:      irttp.h
   4  * Version:       1.0
   5  * Description:   Tiny Transport Protocol (TTP) definitions
   6  * Status:        Experimental.
   7  * Author:        Dag Brattli <dagb@cs.uit.no>
   8  * Created at:    Sun Aug 31 20:14:31 1997
   9  * Modified at:   Sun Dec 12 13:09:07 1999
  10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
  11  *
  12  *     Copyright (c) 1998-1999 Dag Brattli <dagb@cs.uit.no>,
  13  *     All Rights Reserved.
  14  *     Copyright (c) 2000-2002 Jean Tourrilhes <jt@hpl.hp.com>
  15  *
  16  *     This program is free software; you can redistribute it and/or
  17  *     modify it under the terms of the GNU General Public License as
  18  *     published by the Free Software Foundation; either version 2 of
  19  *     the License, or (at your option) any later version.
  20  *
  21  *     Neither Dag Brattli nor University of Tromsø admit liability nor
  22  *     provide warranty for any of this software. This material is
  23  *     provided "AS-IS" and at no charge.
  24  *
  25  ********************************************************************/
  26
  27 #ifndef IRTTP_H
  28 #define IRTTP_H
  29
  30 #include <linux/types.h>
  31 #include <linux/skbuff.h>
  32 #include <linux/spinlock.h>
  33
  34 #include <net/irda/irda.h>
  35 #include <net/irda/irlmp.h>             /* struct lsap_cb */
  36 #include <net/irda/qos.h>               /* struct qos_info */
  37 #include <net/irda/irqueue.h>
  38
  39 #define TTP_MAX_CONNECTIONS    LM_MAX_CONNECTIONS
  40 #define TTP_HEADER             1
  41 #define TTP_MAX_HEADER         (TTP_HEADER + LMP_MAX_HEADER)
  42 #define TTP_SAR_HEADER         5
  43 #define TTP_PARAMETERS         0x80
  44 #define TTP_MORE               0x80
  45
  46 /* Transmission queue sizes */
  47 /* Worst case scenario, two window of data - Jean II */
  48 #define TTP_TX_MAX_QUEUE        14
  49 /* We need to keep at least 5 frames to make sure that we can refill
  50  * appropriately the LAP layer. LAP keeps only two buffers, and we need
  51  * to have 7 to make a full window - Jean II */
  52 #define TTP_TX_LOW_THRESHOLD    5
  53 /* Most clients are synchronous with respect to flow control, so we can
  54  * keep a low number of Tx buffers in TTP - Jean II */
  55 #define TTP_TX_HIGH_THRESHOLD   7
  56
  57 /* Receive queue sizes */
  58 /* Minimum of credit that the peer should hold.
  59  * If the peer has less credits than 9 frames, we will explicitly send
  60  * him some credits (through irttp_give_credit() and a specific frame).
  61  * Note that when we give credits it's likely that it won't be sent in
  62  * this LAP window, but in the next one. So, we make sure that the peer
  63  * has something to send while waiting for credits (one LAP window == 7
  64  * + 1 frames while he process the credits). - Jean II */
  65 #define TTP_RX_MIN_CREDIT       8
  66 /* This is the default maximum number of credits held by the peer, so the
  67  * default maximum number of frames he can send us before needing flow
  68  * control answer from us (this may be negociated differently at TSAP setup).
  69  * We want to minimise the number of times we have to explicitly send some
  70  * credit to the peer, hoping we can piggyback it on the return data. In
  71  * particular, it doesn't make sense for us to send credit more than once
  72  * per LAP window.
  73  * Moreover, giving credits has some latency, so we need strictly more than
  74  * a LAP window, otherwise we may already have credits in our Tx queue.
  75  * But on the other hand, we don't want to keep too many Rx buffer here
  76  * before starting to flow control the other end, so make it exactly one
  77  * LAP window + 1 + MIN_CREDITS. - Jean II */
  78 #define TTP_RX_DEFAULT_CREDIT   16
  79 /* Maximum number of credits we can allow the peer to have, and therefore
  80  * maximum Rx queue size.
  81  * Note that we try to deliver packets to the higher layer every time we
  82  * receive something, so in normal mode the Rx queue will never contains
  83  * more than one or two packets. - Jean II */
  84 #define TTP_RX_MAX_CREDIT       21
  85
  86 /* What clients should use when calling ttp_open_tsap() */
  87 #define DEFAULT_INITIAL_CREDIT  TTP_RX_DEFAULT_CREDIT
  88
  89 /* Some priorities for disconnect requests */
  90 #define P_NORMAL    0
  91 #define P_HIGH      1
  92
  93 #define TTP_SAR_DISABLE 0
  94 #define TTP_SAR_UNBOUND 0xffffffff
  95
  96 /* Parameters */
  97 #define TTP_MAX_SDU_SIZE 0x01
  98
  99 /*
 100  *  This structure contains all data associated with one instance of a TTP
 101  *  connection.
 102  */
 103 struct tsap_cb {
 104         irda_queue_t q;            /* Must be first */
 105         magic_t magic;        /* Just in case */
 106
 107         __u8 stsap_sel;       /* Source TSAP */
 108         __u8 dtsap_sel;       /* Destination TSAP */
 109
 110         struct lsap_cb *lsap; /* Corresponding LSAP to this TSAP */
 111
 112         __u8 connected;       /* TSAP connected */
 113
 114         __u8 initial_credit;  /* Initial credit to give peer */
 115
 116         int avail_credit;    /* Available credit to return to peer */
 117         int remote_credit;   /* Credit held by peer TTP entity */
 118         int send_credit;     /* Credit held by local TTP entity */
 119
 120         struct sk_buff_head tx_queue; /* Frames to be transmitted */
 121         struct sk_buff_head rx_queue; /* Received frames */
 122         struct sk_buff_head rx_fragments;
 123         int tx_queue_lock;
 124         int rx_queue_lock;
 125         spinlock_t lock;
 126
 127         notify_t notify;       /* Callbacks to client layer */
 128
 129         struct net_device_stats stats;
 130         struct timer_list todo_timer;
 131
 132         __u32 max_seg_size;     /* Max data that fit into an IrLAP frame */
 133         __u8  max_header_size;
 134
 135         int   rx_sdu_busy;     /* RxSdu.busy */
 136         __u32 rx_sdu_size;     /* Current size of a partially received frame */
 137         __u32 rx_max_sdu_size; /* Max receive user data size */
 138
 139         int tx_sdu_busy;       /* TxSdu.busy */
 140         __u32 tx_max_sdu_size; /* Max transmit user data size */
 141
 142         int close_pend;        /* Close, but disconnect_pend */
 143         unsigned long disconnect_pend; /* Disconnect, but still data to send */
 144         struct sk_buff *disconnect_skb;
 145 };
 146
 147 struct irttp_cb {
 148         magic_t    magic;
 149         hashbin_t *tsaps;
 150 };
 151
 152 int  irttp_init(void);
 153 void irttp_cleanup(void);
 154
 155 struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify);
 156 int irttp_close_tsap(struct tsap_cb *self);
 157
 158 int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb);
 159 int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb);
 160
 161 int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
 162                           __u32 saddr, __u32 daddr,
 163                           struct qos_info *qos, __u32 max_sdu_size,
 164                           struct sk_buff *userdata);
 165 int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
 166                             struct sk_buff *userdata);
 167 int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *skb,
 168                              int priority);
 169 void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow);
 170 struct tsap_cb *irttp_dup(struct tsap_cb *self, void *instance);
 171
 172 static inline __u32 irttp_get_saddr(struct tsap_cb *self)
 173 {
 174         return irlmp_get_saddr(self->lsap);
 175 }
 176
 177 static inline __u32 irttp_get_daddr(struct tsap_cb *self)
 178 {
 179         return irlmp_get_daddr(self->lsap);
 180 }
 181
 182 static inline __u32 irttp_get_max_seg_size(struct tsap_cb *self)
 183 {
 184         return self->max_seg_size;
 185 }
 186
 187 /* After doing a irttp_dup(), this get one of the two socket back into
 188  * a state where it's waiting incoming connections.
 189  * Note : this can be used *only* if the socket is not yet connected
 190  * (i.e. NO irttp_connect_response() done on this socket).
 191  * - Jean II */
 192 static inline void irttp_listen(struct tsap_cb *self)
 193 {
 194         irlmp_listen(self->lsap);
 195         self->dtsap_sel = LSAP_ANY;
 196 }
 197
 198 /* Return TRUE if the node is in primary mode (i.e. master)
 199  * - Jean II */
 200 static inline int irttp_is_primary(struct tsap_cb *self)
 201 {
 202         if ((self == NULL) ||
 203             (self->lsap == NULL) ||
 204             (self->lsap->lap == NULL) ||
 205             (self->lsap->lap->irlap == NULL))
 206                 return -2;
 207         return irlap_is_primary(self->lsap->lap->irlap);
 208 }
 209
 210 #endif /* IRTTP_H */