1 /*********************************************************************
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>
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>
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.
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.
25 ********************************************************************/
30 #include <linux/types.h>
31 #include <linux/skbuff.h>
32 #include <linux/spinlock.h>
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>
39 #define TTP_MAX_CONNECTIONS LM_MAX_CONNECTIONS
41 #define TTP_MAX_HEADER (TTP_HEADER + LMP_MAX_HEADER)
42 #define TTP_SAR_HEADER 5
43 #define TTP_PARAMETERS 0x80
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
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
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
86 /* What clients should use when calling ttp_open_tsap() */
87 #define DEFAULT_INITIAL_CREDIT TTP_RX_DEFAULT_CREDIT
89 /* Some priorities for disconnect requests */
93 #define TTP_SAR_DISABLE 0
94 #define TTP_SAR_UNBOUND 0xffffffff
97 #define TTP_MAX_SDU_SIZE 0x01
100 * This structure contains all data assosiated with one instance of a TTP
104 irda_queue_t q; /* Must be first */
105 magic_t magic; /* Just in case */
107 __u8 stsap_sel; /* Source TSAP */
108 __u8 dtsap_sel; /* Destination TSAP */
110 struct lsap_cb *lsap; /* Corresponding LSAP to this TSAP */
112 __u8 connected; /* TSAP connected */
114 __u8 initial_credit; /* Initial credit to give peer */
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 */
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;
127 notify_t notify; /* Callbacks to client layer */
129 struct net_device_stats stats;
130 struct timer_list todo_timer;
132 __u32 max_seg_size; /* Max data that fit into an IrLAP frame */
133 __u8 max_header_size;
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 */
139 int tx_sdu_busy; /* TxSdu.busy */
140 __u32 tx_max_sdu_size; /* Max transmit user data size */
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;
152 int irttp_init(void);
153 void irttp_cleanup(void);
155 struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify);
156 int irttp_close_tsap(struct tsap_cb *self);
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);
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,
169 void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow);
170 struct tsap_cb *irttp_dup(struct tsap_cb *self, void *instance);
172 static __inline __u32 irttp_get_saddr(struct tsap_cb *self)
174 return irlmp_get_saddr(self->lsap);
177 static __inline __u32 irttp_get_daddr(struct tsap_cb *self)
179 return irlmp_get_daddr(self->lsap);
182 static __inline __u32 irttp_get_max_seg_size(struct tsap_cb *self)
184 return self->max_seg_size;
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).
192 static inline void irttp_listen(struct tsap_cb *self)
194 irlmp_listen(self->lsap);
195 self->dtsap_sel = LSAP_ANY;
198 /* Return TRUE if the node is in primary mode (i.e. master)
200 static inline int irttp_is_primary(struct tsap_cb *self)
202 if ((self == NULL) ||
203 (self->lsap == NULL) ||
204 (self->lsap->lap == NULL) ||
205 (self->lsap->lap->irlap == NULL))
207 return(irlap_is_primary(self->lsap->lap->irlap));