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 Troms�� 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 explicitely 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 explicitely 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 assosiated with one instance of a TTP
101 *  connection.
102 */
103struct 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
147struct irttp_cb {
148	magic_t    magic;
149	hashbin_t *tsaps;
150};
151
152int  irttp_init(void);
153void irttp_cleanup(void);
154
155struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify);
156int irttp_close_tsap(struct tsap_cb *self);
157
158int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb);
159int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb);
160
161int 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);
165int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
166			    struct sk_buff *userdata);
167int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *skb,
168			     int priority);
169void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow);
170struct tsap_cb *irttp_dup(struct tsap_cb *self, void *instance);
171
172static __inline __u32 irttp_get_saddr(struct tsap_cb *self)
173{
174	return irlmp_get_saddr(self->lsap);
175}
176
177static __inline __u32 irttp_get_daddr(struct tsap_cb *self)
178{
179	return irlmp_get_daddr(self->lsap);
180}
181
182static __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 incomming 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 */
192static 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 */
200static 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 */
211