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1.1 root 1: /*
2: * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3: *
4: * @APPLE_LICENSE_HEADER_START@
5: *
6: * The contents of this file constitute Original Code as defined in and
7: * are subject to the Apple Public Source License Version 1.1 (the
8: * "License"). You may not use this file except in compliance with the
9: * License. Please obtain a copy of the License at
10: * http://www.apple.com/publicsource and read it before using this file.
11: *
12: * This Original Code and all software distributed under the License are
13: * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14: * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15: * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17: * License for the specific language governing rights and limitations
18: * under the License.
19: *
20: * @APPLE_LICENSE_HEADER_END@
21: */
22: /*
23: * RxData.c
24: *
25: * From v01.28 Handle an incoming Data Packet 06/21/90 mbs
26: */
27: /*
28: * Change log:
29: * 06/29/95 - Modified to handle flow control for writing (Tuyen Nguyen)
30: * Modified for MP, 1996 by Tuyen Nguyen
31: * Modified, April 9, 1997 by Tuyen Nguyen for MacOSX.
32: */
33:
34: #include <sys/errno.h>
35: #include <sys/types.h>
36: #include <sys/param.h>
37: #include <machine/spl.h>
38: #include <sys/systm.h>
39: #include <sys/kernel.h>
40: #include <sys/proc.h>
41: #include <sys/filedesc.h>
42: #include <sys/fcntl.h>
43: #include <sys/mbuf.h>
44: #include <sys/socket.h>
45: #include <sys/socketvar.h>
46: #include <sys/time.h>
47:
48: #include <netat/sysglue.h>
49: #include <netat/appletalk.h>
50: #include <netat/at_pcb.h>
51: #include <netat/debug.h>
52: #include <netat/adsp.h>
53: #include <netat/adsp_internal.h>
54:
55: gbuf_t *releaseData(mp, len)
56: gbuf_t *mp;
57: int len;
58: {
59: register gbuf_t *tmp;
60: register int cnt;
61: int freeit;
62:
63: dPrintf(D_M_ADSP, D_L_TRACE,
64: ("releaseData: mbuf=0x%x, len=%d\n", (unsigned)mp, len));
65:
66: KERNEL_DEBUG(DBG_ADSP_RCV, 0, mp, len, 0, 0);
67:
68: do {
69: freeit = 1; /* assume we use the whole mblk */
70: if ((cnt = gbuf_len(mp)) > len) {
71: freeit = 0; /* using only part of the mblk */
72: cnt = len;
73: }
74: gbuf_rinc(mp,cnt);
75: len -= cnt;
76: tmp = mp;
77: mp = gbuf_cont(mp);
78: if (freeit) {
79: gbuf_freeb(tmp);
80: } else
81: return tmp; /* if we don't use the whole block */
82: /* pass back the partial gbuf_t pointer */
83: } while (len && mp);
84: return mp;
85: }
86:
87: /*
88: * CheckRecvSeq
89: *
90: * We just got a non-attention packet. Check the pktNextRecvSeq field
91: * to see if it acknowledges any of our sent data.
92: *
93: * If any data was acked, check to see if we have anything to fill the
94: * newly opened up remote receive window. Otherwise, if the ACK request
95: * bit was set, we need to send an Ack Packet
96: *
97: * Always called as the result of receiving a packet. Interrupts
98: * are completely masked when this routine is called.
99: *
100: * INPUTS:
101: * sp stream
102: * f pointer to ASDP header
103: * OUTPUTS:
104: * none
105: */
106: void CheckRecvSeq(sp, f) /* (CCBPtr sp, ADSP_FRAMEPtr f) */
107: register CCBPtr sp;
108: register ADSP_FRAMEPtr f;
109: {
110: int s;
111: int pktNextRecvSeq;
112: int sendWdwSeq;
113: int eom;
114: int hlen;
115: register gbuf_t *mp;
116:
117: ATDISABLE(s, sp->lock);
118: if (f->descriptor & ADSP_ACK_REQ_BIT) { /* He wants an Ack */
119: sp->sendDataAck = 1;
120: sp->callSend = 1;
121: }
122:
123: pktNextRecvSeq = netdw(UAL_VALUE(f->pktNextRecvSeq)); /* Local copy */
124:
125: /*
126: * Make sure the sequence number corresponds to reality -- i.e. for
127: * unacknowledged data that we have sent
128: */
129:
130: if (GT(pktNextRecvSeq, sp->maxSendSeq)) /* We've never sent this seq #! */
131: goto noack;
132:
133: if (GTE(pktNextRecvSeq, sp->timerSeq) && sp->waitingAck) {
134: /* This acks our Ack Request */
135: sp->waitingAck = 0; /* Allow sending more */
136: sp->pktSendCnt = 0; /* Reset packet count */
137: /* Remove retry timer */
138: RemoveTimerElem(&adspGlobal.fastTimers, &sp->RetryTimer);
139:
140: if (!sp->resentData) { /* Data sent without retries */
141: short diff; /* Signed!! */
142: /* All timings done in 6th second base */
143: /* The contortions here are to prevent C from promoting
144: * everything to longs and then using a library routine
145: * to do the division. As 16-bit words, a DIVU instruction
146: * is used.
147: */
148:
149: diff = (((word)(SysTicks() - sp->sendStamp)) / (word)10) -
150: sp->roundTrip + 1;
151:
152: sp->roundTrip += diff >> 3; /* Update average */
153:
154: if (diff < 0) /* Take absolute value */
155: diff = -diff;
156: sp->deviation += (diff - sp->deviation) >> 2; /* Update deviation*/
157:
158: sp->rtmtInterval = sp->roundTrip +
159: ((short)2 * (short)sp->deviation);
160:
161: if (!sp->noXmitFlow &&
162: sp->pktSendMax < 50) /* Bump # of sequential */
163: sp->pktSendMax++; /* Packets we'll send */
164:
165: sp->noXmitFlow = 0;
166: }
167: else
168: sp->resentData = 0;
169:
170: } /* Acked our data */
171:
172: if (LTE(pktNextRecvSeq,
173: sp->firstRtmtSeq)) /* Was duplicate ack, so ignore */
174: goto noack;
175:
176: if (!sp->sData) /* If nothing in send queue, ignore */
177: goto noack;
178:
179:
180: do { /* This acks bytes in our buffer */
181: if (mp = sp->sbuf_mb) { /* Get ptr to oldest data header */
182: sp->sbuf_mb = gbuf_next(mp); /* unlink it from send queue */
183: eom = 1;
184: } else {
185: mp = sp->csbuf_mb;
186: sp->csbuf_mb = 0;
187: eom = 0;
188: }
189:
190: if (mp == 0) { /* shouldn't happen! */
191: sp->sData = 0;
192: goto noack;
193: }
194: /*
195: * Does this ack the entire data block we're now pointing at?
196: */
197: if (LTE((sp->firstRtmtSeq + eom + (hlen = gbuf_msgsize(mp))),
198: pktNextRecvSeq)) {
199:
200: gbuf_freem(mp);
201:
202: /* Update seq # of oldest byte in bfr */
203: sp->firstRtmtSeq += eom + hlen;
204:
205: if ((sp->sbuf_mb == 0) && (sp->csbuf_mb == 0)) {
206: /* If this was only block, then ... */
207: sp->sData = 0; /* ... no data in queue */
208: sp->writeFlush = 0;
209: if (sp->state == sClosing) /* this may allow us to close... */
210: CheckOkToClose(sp);
211: atalk_enablew(sp->gref);
212: break;
213: }
214: } /* whole data block acked */
215: else /* Only some of the data was acked */
216: {
217: short acked;
218:
219: acked = (pktNextRecvSeq - sp->firstRtmtSeq);
220: mp = releaseData(mp, acked);
221: if (eom) {
222: if (mp) {
223: gbuf_next(mp) = sp->sbuf_mb;
224: sp->sbuf_mb = mp;
225: }
226: } else
227: sp->csbuf_mb = mp;
228:
229: sp->firstRtmtSeq = pktNextRecvSeq; /* Update seq # oldest byte */
230: break;
231: }
232: } while (LT(sp->firstRtmtSeq, pktNextRecvSeq));
233:
234: if (sp->sData) /* We've got stuff to send */
235: sp->callSend = 1;
236:
237: noack:
238: sendWdwSeq = netw(UAS_VALUE(f->pktRecvWdw)) - 1 + pktNextRecvSeq;
239:
240: if (GT(sendWdwSeq, sp->sendWdwSeq)) /* Don't make send window smaller */
241: {
242: sp->callSend = 1; /* His recv wdw opened, so see */
243: /* if we can send more data */
244: sp->sendWdwSeq = sendWdwSeq;
245: }
246: ATENABLE(s, sp->lock);
247: }
248:
249: /*
250: * RXData
251: *
252: * We just got a Data Packet
253: * See if it came from anybody we know.
254: *
255: * Called from ADSP Packet with interrupts masked completely OFF
256: * *** In MacOSX interrupts do not seem to be off! ***
257: *
258: * INPUTS:
259: * Stream pointer
260: * gbuf_t pointer
261: * Pointer to ADSP header, (part of the mblk pointer to by mp)
262: * Length of header plus data
263: * OUTPUTS:
264: * Returns 1 if packet was ignored
265: */
266: int RXData(sp, mp, f, len) /* (CCBPtr sp, ADSP_FRAMEPtr f, word len) */
267: CCBPtr sp;
268: register gbuf_t *mp;
269: ADSP_FRAMEPtr f;
270: int len;
271: {
272: int s, offset;
273: int PktFirstByteSeq;
274: short cnt;
275: char eom;
276:
277: len -= ADSP_FRAME_LEN;
278:
279: /* Does packet have eom bit set? */
280: eom = (f->descriptor & ADSP_EOM_BIT) ? 1 : 0;
281:
282: dPrintf(D_M_ADSP, D_L_TRACE,
283: ("RXData: sp=0x%x, mbuf=0x%x, f=0x%x, len=%d, eom=%d\n",
284: (unsigned)sp, (unsigned)mp, (unsigned)f, len, eom));
285:
286: KERNEL_DEBUG(DBG_ADSP_RCV, 1, sp, mp, len, eom);
287:
288: trace_mbufs(D_M_ADSP, " mp", mp);
289:
290: PktFirstByteSeq = netdw(UAL_VALUE(f->pktFirstByteSeq)); /* Local copy */
291:
292: ATDISABLE(s, sp->lock);
293: if (GT(PktFirstByteSeq, sp->recvSeq)) /* missed a packet (out of order) */
294: {
295: if (sp->badSeqCnt++ > sp->badSeqCnt) /* Need to send rexmit advice */
296: sp->sendCtl |= B_CTL_RETRANSMIT;
297: ATENABLE(s, sp->lock);
298: CheckRecvSeq(sp, f); /* Will set send ACK flag if requested */
299: CheckReadQueue(sp);
300: gbuf_freem(mp);
301:
302: KERNEL_DEBUG(DBG_ADSP_RCV, 2, sp, 0, 0, 0);
303: trace_mbufs(D_M_ADSP, " exRXD m", sp->rbuf_mb);
304: dPrintf(D_M_ADSP, D_L_TRACE, (" End RXData - missed a packet\n"));
305:
306: return 0;
307: }
308:
309: if (LTE(PktFirstByteSeq + len + eom, sp->recvSeq)) { /* duplicate data? */
310: ATENABLE(s, sp->lock);
311: CheckRecvSeq(sp, f); /* Will set send ACK flag if requested */
312: CheckReadQueue(sp);
313: gbuf_freem(mp);
314:
315: KERNEL_DEBUG(DBG_ADSP_RCV, 3, sp, 0, 0, 0);
316: trace_mbufs(D_M_ADSP, " exRXD m", sp->rbuf_mb);
317: dPrintf(D_M_ADSP, D_L_TRACE, (" End RXData - duplicate data\n"));
318:
319: return 0;
320: }
321:
322: sp->badSeqCnt = 0; /* reset out of sequence pckt counter */
323:
324: cnt = sp->recvSeq - PktFirstByteSeq; /* # bytes we've seen already */
325:
326: offset = ((unsigned char *)&f->data[cnt]) - (unsigned char *)gbuf_rptr(mp);
327: gbuf_rinc(mp,offset);
328: /* point recv mblk to data (past headers) */
329:
330: len -= cnt; /* # of new data bytes */
331:
332: cnt = len; /* # bytes left to deal with */
333:
334: if (!sp->rData) /* Recv bfr is empty */
335: {
336: sp->rData = 1; /* Not empty any more */
337:
338: if ((sp->rpb)->ioc == mp) {
339: dPrintf(D_M_ADSP, D_L_TRACE,
340: ("RXData: (pb->ioc == mp) no stored data\n"));
341: KERNEL_DEBUG(DBG_ADSP_RCV, 4, sp, sp->rpb, 0, 0);
342: }
343: if (eom)
344: sp->rbuf_mb = mp;
345: else
346: sp->crbuf_mb = mp;
347: } /* Recv queue is empty */
348:
349: /*
350: * Else, there's already stored data.
351: */
352: else {
353: gbuf_t *rmp;
354: /*
355: * Is this a new "message?"
356: */
357: if (eom) {
358: if (sp->crbuf_mb) {
359: gbuf_linkb(sp->crbuf_mb, mp);
360: mp = sp->crbuf_mb;
361: sp->crbuf_mb = 0;
362: }
363: if (rmp = sp->rbuf_mb) {
364: /*
365: * Add it to the end
366: */
367: while(gbuf_next(rmp))
368: rmp = gbuf_next(rmp);
369: gbuf_next(rmp) = mp;
370: } else
371: sp->rbuf_mb = mp;
372: } else if (sp->crbuf_mb)
373: gbuf_linkb(sp->crbuf_mb, mp);
374: else
375: sp->crbuf_mb = mp;
376: }
377: sp->recvSeq += (cnt + eom); /* We've got these bytes */
378:
379: /* %%% We really should call check recv seq first, but let's
380: * continue to do it down here. We really want to service the
381: * received packet first, and maybe reenable scc ints before
382: * doing anything that might take a long while
383: */
384:
385: ATENABLE(s, sp->lock);
386: CheckRecvSeq(sp, f); /* Will set send ACK flag if requested */
387: CheckReadQueue(sp);
388: KERNEL_DEBUG(DBG_ADSP_RCV, 5, sp, sp->rbuf_mb, 0, 0);
389: trace_mbufs(D_M_ADSP, " eRXD m", sp->rbuf_mb);
390: return 0;
391: } /* RXData */
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