xref: /csrg-svn/sys/netiso/tp_pcb.h (revision 51138)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)tp_pcb.h	7.16 (Berkeley) 09/17/91
8  */
9 
10 /***********************************************************
11 		Copyright IBM Corporation 1987
12 
13                       All Rights Reserved
14 
15 Permission to use, copy, modify, and distribute this software and its
16 documentation for any purpose and without fee is hereby granted,
17 provided that the above copyright notice appear in all copies and that
18 both that copyright notice and this permission notice appear in
19 supporting documentation, and that the name of IBM not be
20 used in advertising or publicity pertaining to distribution of the
21 software without specific, written prior permission.
22 
23 IBM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
24 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
25 IBM BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
26 ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
27 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
28 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
29 SOFTWARE.
30 
31 ******************************************************************/
32 
33 /*
34  * ARGO Project, Computer Sciences Dept., University of Wisconsin - Madison
35  */
36 /*
37  * ARGO TP
38  *
39  * $Header: tp_pcb.h,v 5.2 88/11/18 17:09:32 nhall Exp $
40  * $Source: /usr/argo/sys/netiso/RCS/tp_pcb.h,v $
41  *
42  *
43  * This file defines the transport protocol control block (tpcb).
44  * and a bunch of #define values that are used in the tpcb.
45  */
46 
47 #ifndef  __TP_PCB__
48 #define  __TP_PCB__
49 
50 #include "../netiso/tp_param.h"
51 #include "../netiso/tp_timer.h"
52 #include "../netiso/tp_user.h"
53 #ifndef sblock
54 #include "socketvar.h"
55 #endif sblock
56 
57 /* NOTE: the code depends on REF_CLOSED > REF_OPEN > the rest, and
58  * on REF_FREE being zero
59  *
60  * Possible improvement:
61  * think about merging the tp_ref w/ the tpcb and doing a search
62  * through the tpcb list, from tpb. This would slow down lookup
63  * during data transfer
64  * It would be a little nicer also to have something based on the
65  * clock (like top n bits of the reference is part of the clock, to
66  * minimize the likelihood  of reuse after a crash)
67  * also, need to keep the timer servicing part to a minimum (although
68  * the cost of this is probably independent of whether the timers are
69  * in the pcb or in an array..
70  * Last, would have to make the number of timers a function of the amount of
71  * mbufs available, plus some for the frozen references.
72  *
73  * Possible improvement:
74  * Might not need the ref_state stuff either...
75  * REF_FREE could correspond to tp_state == CLOSED or nonexistend tpcb,
76  * REF_OPEN to tp_state anywhere from AK_WAIT or CR_SENT to CLOSING
77  * REF_OPENING could correspond to LISTENING, because that's the
78  * way it's used, not because the correspondence is exact.
79  * REF_CLOSED could correspond to REFWAIT
80  */
81 #define REF_FROZEN 3	/* has ref timer only */
82 #define REF_OPEN 2		/* has timers, possibly active */
83 #define REF_OPENING 1	/* in use (has a pcb) but no timers */
84 #define REF_FREE 0		/* free to reallocate */
85 
86 #define N_CTIMERS 		6
87 
88 struct tp_ref {
89 /*	u_char	 			tpr_state; /* values REF_FROZEN, etc. above */
90 /*	struct Ccallout 	tpr_callout[N_CTIMERS]; /* C timers */
91 /*	struct Ecallout		tpr_calltodo;			/* list of active E timers */
92 #define	tpr_state		tpr_pcb->tp_refstate
93 #define	tpr_callout		tpr_pcb->tp_refcallout
94 #define	tpr_calltodo 	tpr_pcb->tp_refcalltodo
95 	struct tp_pcb 		*tpr_pcb;	/* back ptr to PCB */
96 };
97 
98 struct tp_refinfo {
99 	struct tp_ref		*tpr_base;
100 	int					tpr_size;
101 	int					tpr_maxopen;
102 	int					tpr_numopen;
103 };
104 
105 struct tp_param {
106 	/* PER system stuff (one static structure instead of a bunch of names) */
107 	unsigned 	tpp_configed:1;			/* Has TP been initialized? */
108 };
109 
110 
111 struct nl_protosw {
112 	int		nlp_afamily;			/* address family */
113 	int		(*nlp_putnetaddr)();	/* puts addresses in nl pcb */
114 	int		(*nlp_getnetaddr)();	/* gets addresses from nl pcb */
115 	int		(*nlp_cmpnetaddr)();	/* compares address in pcb with sockaddr */
116 	int		(*nlp_putsufx)();		/* puts transport suffixes in nl pcb */
117 	int		(*nlp_getsufx)();		/* gets transport suffixes from nl pcb */
118 	int		(*nlp_recycle_suffix)();/* clears suffix from nl pcb */
119 	int		(*nlp_mtu)();			/* figures out mtu based on nl used */
120 	int		(*nlp_pcbbind)();		/* bind to pcb for net level */
121 	int		(*nlp_pcbconn)();		/* connect for net level */
122 	int		(*nlp_pcbdisc)();		/* disconnect net level */
123 	int		(*nlp_pcbdetach)();		/* detach net level pcb */
124 	int		(*nlp_pcballoc)();		/* allocate a net level pcb */
125 	int		(*nlp_output)();		/* prepare a packet to give to nl */
126 	int		(*nlp_dgoutput)();		/* prepare a packet to give to nl */
127 	int		(*nlp_ctloutput)();		/* hook for network set/get options */
128 	caddr_t	nlp_pcblist;			/* list of xx_pcb's for connections */
129 };
130 
131 
132 struct tp_pcb {
133 	struct tp_pcb		*tp_next;
134 	struct tp_pcb		*tp_prev;
135 	struct tp_pcb		*tp_nextlisten; /* chain all listeners */
136 	u_short 			tp_state;		/* state of fsm */
137 	short 				tp_retrans;		/* # times can still retrans */
138 	struct tp_ref 		*tp_refp;		/* rest of pcb	*/
139 	caddr_t				tp_npcb;		/* to lower layer pcb */
140 	struct nl_protosw	*tp_nlproto;	/* lower-layer dependent routines */
141 	struct socket 		*tp_sock;		/* back ptr */
142 
143 
144 	RefNum				tp_lref;	 	/* local reference */
145 	RefNum 				tp_fref;		/* foreign reference */
146 
147 	u_int				tp_seqmask;		/* mask for seq space */
148 	u_int				tp_seqbit;		/* bit for seq number wraparound */
149 	u_int				tp_seqhalf;		/* half the seq space */
150 
151 	struct mbuf			*tp_ucddata;	/* user connect/disconnect data */
152 
153 	/* credit & sequencing info for SENDING */
154 	u_short 			tp_fcredit;		/* current remote credit in # packets */
155 	u_short				tp_ssthresh;	/* cong_win threshold for slow start
156 										 * exponential to linear switch
157 										 */
158 	u_short				tp_cong_win;	/* congestion window : set to 1 on
159 										 * source quench
160 										 * Minimizes the amount of retrans-
161 										 * missions (independently of the
162 										 * retrans strategy).  Increased
163 										 * by one for each good ack received.
164 										 * Minimizes the amount sent in a
165 										 * regular tp_send() also.
166 										 */
167 	u_int   tp_ackrcvd; /* ACKs received since the send window was updated */
168 	SeqNum              tp_last_retrans;
169 	SeqNum              tp_retrans_hiwat;
170 	SeqNum				tp_snduna;		/* seq # of lowest unacked DT */
171 	SeqNum				tp_sndhiwat;	/* highest seq # sent so far */
172 	SeqNum				tp_sndnum;		/* next seq # to be assigned */
173 	struct mbuf			*tp_sndhiwat_m; /* packet corres. to sndhiwat*/
174 	int					tp_Nwindow;		/* for perf. measurement */
175 
176 	/* credit & sequencing info for RECEIVING */
177 	SeqNum	 			tp_sent_lcdt;	/* cdt according to last ack sent */
178 	SeqNum	 			tp_sent_uwe;	/* uwe according to last ack sent */
179 	SeqNum				tp_rcvnxt;		/* next DT seq # expect to recv */
180 	SeqNum	 			tp_sent_rcvnxt;	/* rcvnxt according to last ack sent
181 										 * needed for perf measurements only
182 										 */
183 	u_short				tp_lcredit;		/* current local credit in # packets */
184 	u_short				tp_maxlcredit;	/* needed for reassembly queue */
185 	struct mbuf			**tp_rsyq;		/* unacked stuff recvd out of order */
186 	int					tp_rsycnt;		/* number of packets */
187 
188 	/* receiver congestion state stuff ...  */
189 	u_int               tp_win_recv;
190 
191 	/* receive window as a scaled int (8 bit fraction part) */
192 
193 	struct cong_sample {
194 		ushort  cs_size; 				/* current window size */
195 		ushort  cs_received;   			/* PDUs received in this sample */
196 		ushort  cs_ce_set;    /* PDUs received in this sample with CE bit set */
197 	} tp_cong_sample;
198 
199 
200 	/* parameters per-connection controllable by user */
201 	struct tp_conn_param _tp_param;
202 
203 #define	tp_Nretrans _tp_param.p_Nretrans
204 #define	tp_dr_ticks _tp_param.p_dr_ticks
205 #define	tp_cc_ticks _tp_param.p_cc_ticks
206 #define	tp_dt_ticks _tp_param.p_dt_ticks
207 #define	tp_xpd_ticks _tp_param.p_x_ticks
208 #define	tp_cr_ticks _tp_param.p_cr_ticks
209 #define	tp_keepalive_ticks _tp_param.p_keepalive_ticks
210 #define	tp_sendack_ticks _tp_param.p_sendack_ticks
211 #define	tp_refer_ticks _tp_param.p_ref_ticks
212 #define	tp_inact_ticks _tp_param.p_inact_ticks
213 #define	tp_xtd_format _tp_param.p_xtd_format
214 #define	tp_xpd_service _tp_param.p_xpd_service
215 #define	tp_ack_strat _tp_param.p_ack_strat
216 #define	tp_rx_strat _tp_param.p_rx_strat
217 #define	tp_use_checksum _tp_param.p_use_checksum
218 #define	tp_use_efc _tp_param.p_use_efc
219 #define	tp_use_nxpd _tp_param.p_use_nxpd
220 #define	tp_use_rcc _tp_param.p_use_rcc
221 #define	tp_tpdusize _tp_param.p_tpdusize
222 #define	tp_class _tp_param.p_class
223 #define	tp_winsize _tp_param.p_winsize
224 #define	tp_no_disc_indications _tp_param.p_no_disc_indications
225 #define	tp_dont_change_params _tp_param.p_dont_change_params
226 #define	tp_netservice _tp_param.p_netservice
227 #define	tp_version _tp_param.p_version
228 
229 	int					tp_l_tpdusize;
230 		/* whereas tp_tpdusize is log2(the negotiated max size)
231 		 * l_tpdusize is the size we'll use when sending, in # chars
232 		 */
233 
234 	int					tp_rtv;			/* max round-trip time variance */
235 	int					tp_rtt; 		/* smoothed round-trip time */
236 	SeqNum				tp_rttseq;		/* packet being timed */
237 	int					tp_rttemit;		/* when emitted, in ticks */
238 	int					tp_idle;		/* last activity, in ticks */
239 	short				tp_rxtcur;		/* current retransmit value */
240 	short				tp_rxtshift;	/* log(2) of rexmt exp. backoff */
241 
242 	unsigned
243 		tp_sendfcc:1,			/* shall next ack include FCC parameter? */
244 		tp_trace:1,				/* is this pcb being traced? (not used yet) */
245 		tp_perf_on:1,			/* 0/1 -> performance measuring on  */
246 		tp_reneged:1,			/* have we reneged on cdt since last ack? */
247 		tp_decbit:3,			/* dec bit was set, we're in reneg mode  */
248 		tp_cebit_off:1,			/* the real DEC bit algorithms not in use */
249 		tp_flags:8,				/* values: */
250 #define TPF_NLQOS_PDN	 	TPFLAG_NLQOS_PDN
251 #define TPF_PEER_ON_SAMENET	TPFLAG_PEER_ON_SAMENET
252 #define TPF_GENERAL_ADDR	TPFLAG_GENERAL_ADDR
253 #define TPF_DELACK			0x8
254 #define TPF_ACKNOW			0x10
255 
256 #define PEER_IS_LOCAL(t)	(((t)->tp_flags & TPF_PEER_ON_SAME_NET) != 0)
257 #define USES_PDN(t)			(((t)->tp_flags & TPF_NLQOS_PDN) != 0)
258 
259 		tp_oktonagle:1,			/* Last unsent packet that may be append to */
260 		tp_notdetached:1,		/* Call tp_detach before freeing XXXXXXX */
261 		tp_unused:14;
262 
263 
264 #ifdef TP_PERF_MEAS
265 	/* performance stats - see tp_stat.h */
266 	struct tp_pmeas		*tp_p_meas;
267 	struct mbuf			*tp_p_mbuf;
268 #endif TP_PERF_MEAS
269 	/* addressing */
270 	u_short				tp_domain;		/* domain (INET, ISO) */
271 	/* for compatibility with the *old* way and with INET, be sure that
272 	 * that lsuffix and fsuffix are aligned to a short addr.
273 	 * having them follow the u_short *suffixlen should suffice (choke)
274 	 */
275 	u_short				tp_fsuffixlen;	/* foreign suffix */
276 	char				tp_fsuffix[MAX_TSAP_SEL_LEN];
277 	u_short				tp_lsuffixlen;	/* local suffix */
278 	char				tp_lsuffix[MAX_TSAP_SEL_LEN];
279 #define SHORT_LSUFXP(tpcb) ((short *)((tpcb)->tp_lsuffix))
280 #define SHORT_FSUFXP(tpcb) ((short *)((tpcb)->tp_fsuffix))
281 
282 	/* Timer stuff */
283 	u_char 				tp_vers;			/* protocol version */
284 	u_char 				tp_peer_acktime;	/* used for DT retrans time */
285 	u_char	 			tp_refstate;		/* values REF_FROZEN, etc. above */
286 	struct tp_pcb		*tp_fasttimeo;		/* limit pcbs to examine */
287 	struct Ccallout 	tp_refcallout[N_CTIMERS]; /* C timers */
288 	struct Ecallarg		tp_retransargs;		/* dunt ask ... */
289 
290 	struct sockbuf		tp_Xsnd;		/* for expedited data */
291 /*	struct sockbuf		tp_Xrcv;		/* for expedited data */
292 #define tp_Xrcv tp_sock->so_rcv
293 	SeqNum				tp_Xsndnxt;	/* next XPD seq # to send */
294 	SeqNum				tp_Xuna;		/* seq # of unacked XPD */
295 	SeqNum				tp_Xrcvnxt;	/* next XPD seq # expect to recv */
296 
297 	/* AK subsequencing */
298 	u_short				tp_s_subseq;	/* next subseq to send */
299 	u_short				tp_r_subseq;	/* highest recv subseq */
300 
301 };
302 
303 u_int	tp_start_win;
304 
305 #define ROUND(scaled_int) (((scaled_int) >> 8) + (((scaled_int) & 0x80) ? 1:0))
306 
307 /* to round off a scaled int with an 8 bit fraction part */
308 
309 #define CONG_INIT_SAMPLE(pcb) \
310 	pcb->tp_cong_sample.cs_received = \
311     pcb->tp_cong_sample.cs_ce_set = 0; \
312     pcb->tp_cong_sample.cs_size = MAX(pcb->tp_lcredit, 1) << 1;
313 
314 #define CONG_UPDATE_SAMPLE(pcb, ce_bit) \
315     pcb->tp_cong_sample.cs_received++; \
316     if (ce_bit) { \
317         pcb->tp_cong_sample.cs_ce_set++; \
318     } \
319     if (pcb->tp_cong_sample.cs_size <= pcb->tp_cong_sample.cs_received) { \
320         if ((pcb->tp_cong_sample.cs_ce_set << 1) >=  \
321                     pcb->tp_cong_sample.cs_size ) { \
322             pcb->tp_win_recv -= pcb->tp_win_recv >> 3; /* multiply by .875 */ \
323             pcb->tp_win_recv = MAX(1 << 8, pcb->tp_win_recv); \
324         } \
325         else { \
326             pcb->tp_win_recv += (1 << 8); /* add one to the scaled int */ \
327         } \
328         pcb->tp_lcredit = ROUND(pcb->tp_win_recv); \
329         CONG_INIT_SAMPLE(pcb); \
330     }
331 
332 #define CONG_ACK(pcb, seq) \
333 { int   newacks = SEQ_SUB(pcb, seq, pcb->tp_snduna); \
334 	if (newacks > 0) { \
335 		pcb->tp_ackrcvd += newacks; \
336 		if (pcb->tp_ackrcvd >= MIN(pcb->tp_fcredit, pcb->tp_cong_win)) { \
337 			++pcb->tp_cong_win; \
338 			pcb->tp_ackrcvd = 0; \
339 		} \
340 	} \
341 }
342 
343 #ifdef KERNEL
344 extern struct tp_refinfo 	tp_refinfo;
345 extern struct timeval 	time;
346 extern struct tp_ref	*tp_ref;
347 extern struct tp_param	tp_param;
348 extern struct nl_protosw  nl_protosw[];
349 extern struct tp_pcb	*tp_listeners;
350 extern struct tp_pcb	*tp_ftimeolist;
351 #endif
352 
353 #define	sototpcb(so) 	((struct tp_pcb *)(so->so_pcb))
354 #define	sototpref(so)	((sototpcb(so)->tp_ref))
355 #define	tpcbtoso(tp)	((struct socket *)((tp)->tp_sock))
356 #define	tpcbtoref(tp)	((struct tp_ref *)((tp)->tp_ref))
357 
358 #endif  __TP_PCB__
359