summaryrefslogtreecommitdiff
path: root/device/ds_routines.c
blob: f7ca4e6e0dd90d6905b9d4e5809713e673a0a4fc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
/*
 * Mach Operating System
 * Copyright (c) 1993,1991,1990,1989 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 *	Author: David B. Golub, Carnegie Mellon University
 *	Date: 	3/89
 */

#include <string.h>

#include <mach/boolean.h>
#include <mach/kern_return.h>
#include <mach/mig_errors.h>
#include <mach/port.h>
#include <mach/vm_param.h>
#include <mach/notify.h>
#include <machine/machspl.h>		/* spl definitions */

#include <ipc/ipc_port.h>
#include <ipc/ipc_space.h>

#include <kern/ast.h>
#include <kern/counters.h>
#include <kern/queue.h>
#include <kern/zalloc.h>
#include <kern/thread.h>
#include <kern/task.h>
#include <kern/sched_prim.h>

#include <vm/memory_object.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>

#include <device/device_types.h>
#include <device/dev_hdr.h>
#include <device/conf.h>
#include <device/io_req.h>
#include <device/ds_routines.h>
#include <device/net_status.h>
#include <device/device_port.h>
#include <device/device_reply.user.h>

#include <machine/machspl.h>

#ifdef i386
#include <i386at/device_emul.h>
#endif

#ifdef i386
ipc_port_t
mach_convert_device_to_port (void *d)
{
  ipc_port_t port;
  mach_device_t device = d;

  if (! device)
    return IP_NULL;
  device_lock(device);
  if (device->state == DEV_STATE_OPEN)
    port = ipc_port_make_send(device->port);
  else
    port = IP_NULL;
  device_unlock(device);
  mach_device_deallocate(device);
  return port;
}
#endif /* i386 */

#ifdef i386
static io_return_t
device_open(reply_port, reply_port_type, mode, name, device_p)
#else
io_return_t
ds_device_open(open_port, reply_port, reply_port_type,
	       mode, name, device_p)
	ipc_port_t	open_port;
#endif
	ipc_port_t	reply_port;
	mach_msg_type_name_t reply_port_type;
	dev_mode_t	mode;
	char *		name;
	device_t	*device_p;	/* out */
{
	register mach_device_t	device;
	register kern_return_t	result;
	register io_req_t	ior;
	char			namebuf[64];
	ipc_port_t		notify;

#ifndef i386
	/*
	 * Open must be called on the master device port.
	 */
	if (open_port != master_device_port)
	    return (D_INVALID_OPERATION);

	/*
	 * There must be a reply port.
	 */
	if (!IP_VALID(reply_port)) {
	    printf("ds_* invalid reply port\n");
	    Debugger("ds_* reply_port");
	    return (MIG_NO_REPLY);	/* no sense in doing anything */
	}

#endif	/* ! i386 */

	/*
	 * Find the device.
	 */
	device = device_lookup(name);
	if (device == MACH_DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);

	/*
	 * If the device is being opened or closed,
	 * wait for that operation to finish.
	 */
	device_lock(device);
	while (device->state == DEV_STATE_OPENING ||
		device->state == DEV_STATE_CLOSING) {
	    device->io_wait = TRUE;
	    thread_sleep((event_t)device, simple_lock_addr(device->lock), TRUE);
	    device_lock(device);
	}

	/*
	 * If the device is already open, increment the open count
	 * and return.
	 */
	if (device->state == DEV_STATE_OPEN) {

	    if (device->flag & D_EXCL_OPEN) {
		/*
		 * Cannot open a second time.
		 */
		device_unlock(device);
		mach_device_deallocate(device);
		return (D_ALREADY_OPEN);
	    }

	    device->open_count++;
	    device_unlock(device);
#ifdef i386
	    *device_p = &device->dev;
#else
	    *device_p = device;
#endif
	    return (D_SUCCESS);
	    /*
	     * Return deallocates device reference while acquiring
	     * port.
	     */
	}

	/*
	 * Allocate the device port and register the device before
	 * opening it.
	 */
	device->state = DEV_STATE_OPENING;
	device_unlock(device);

	/*
	 * Allocate port, keeping a reference for it.
	 */
	device->port = ipc_port_alloc_kernel();
	if (device->port == IP_NULL) {
	    device_lock(device);
	    device->state = DEV_STATE_INIT;
	    device->port = IP_NULL;
	    if (device->io_wait) {
		device->io_wait = FALSE;
		thread_wakeup((event_t)device);
	    }
	    device_unlock(device);
	    mach_device_deallocate(device);
	    return (KERN_RESOURCE_SHORTAGE);
	}

	dev_port_enter(device);

	/*
	 * Request no-senders notifications on device port.
	 */
	notify = ipc_port_make_sonce(device->port);
	ip_lock(device->port);
	ipc_port_nsrequest(device->port, 1, notify, &notify);
	assert(notify == IP_NULL);

	/*
	 * Open the device.
	 */
	io_req_alloc(ior, 0);

	ior->io_device	= device;
	ior->io_unit	= device->dev_number;
	ior->io_op	= IO_OPEN | IO_CALL;
	ior->io_mode	= mode;
	ior->io_error	= 0;
	ior->io_done	= ds_open_done;
	ior->io_reply_port = reply_port;
	ior->io_reply_port_type = reply_port_type;

	result = (*device->dev_ops->d_open)(device->dev_number, (int)mode, ior);
	if (result == D_IO_QUEUED)
	    return (MIG_NO_REPLY);

	/*
	 * Return result via ds_open_done.
	 */
	ior->io_error = result;
	(void) ds_open_done(ior);

	io_req_free(ior);

	return (MIG_NO_REPLY);	/* reply already sent */
}

boolean_t
ds_open_done(ior)
	register io_req_t	ior;
{
	kern_return_t		result;
	register mach_device_t	device;

	device = ior->io_device;
	result = ior->io_error;

	if (result != D_SUCCESS) {
	    /*
	     * Open failed.  Deallocate port and device.
	     */
	    dev_port_remove(device);
	    ipc_port_dealloc_kernel(device->port);
	    device->port = IP_NULL;

	    device_lock(device);
	    device->state = DEV_STATE_INIT;
	    if (device->io_wait) {
		device->io_wait = FALSE;
		thread_wakeup((event_t)device);
	    }
	    device_unlock(device);

	    mach_device_deallocate(device);
	    device = MACH_DEVICE_NULL;
	}
	else {
	    /*
	     * Open succeeded.
	     */
	    device_lock(device);
	    device->state = DEV_STATE_OPEN;
	    device->open_count = 1;
	    if (device->io_wait) {
		device->io_wait = FALSE;
		thread_wakeup((event_t)device);
	    }
	    device_unlock(device);

	    /* donate device reference to get port */
	}
	/*
	 * Must explicitly convert device to port, since
	 * device_reply interface is built as 'user' side
	 * (thus cannot get translation).
	 */
	if (IP_VALID(ior->io_reply_port)) {
		(void) ds_device_open_reply(ior->io_reply_port,
					    ior->io_reply_port_type,
					    result,
#ifdef i386
					    (mach_convert_device_to_port
					     (device)));
#else
					    convert_device_to_port(device));
#endif
	} else
		mach_device_deallocate(device);

	return (TRUE);
}

#ifdef i386
static io_return_t
device_close(device)
#else
io_return_t
ds_device_close(device)
#endif
	register mach_device_t	device;
{
#ifndef i386
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	device_lock(device);

	/*
	 * If device will remain open, do nothing.
	 */
	if (--device->open_count > 0) {
	    device_unlock(device);
	    return (D_SUCCESS);
	}

	/*
	 * If device is being closed, do nothing.
	 */
	if (device->state == DEV_STATE_CLOSING) {
	    device_unlock(device);
	    return (D_SUCCESS);
	}

	/*
	 * Mark device as closing, to prevent new IO.
	 * Outstanding IO will still be in progress.
	 */
	device->state = DEV_STATE_CLOSING;
	device_unlock(device);

	/*
	 * ? wait for IO to end ?
	 *   only if device wants to
	 */

	/*
	 * Remove the device-port association.
	 */
	dev_port_remove(device);
	ipc_port_dealloc_kernel(device->port);

	/*
	 * Close the device
	 */
	(*device->dev_ops->d_close)(device->dev_number);

	/*
	 * Finally mark it closed.  If someone else is trying
	 * to open it, the open can now proceed.
	 */
	device_lock(device);
	device->state = DEV_STATE_INIT;
	if (device->io_wait) {
	    device->io_wait = FALSE;
	    thread_wakeup((event_t)device);
	}
	device_unlock(device);

	return (D_SUCCESS);
}

/*
 * Write to a device.
 */
#ifdef i386
static io_return_t
device_write(d, reply_port, reply_port_type, mode, recnum,
	     data, data_count, bytes_written)
	void *d;
#else
io_return_t
ds_device_write(device, reply_port, reply_port_type, mode, recnum,
		data, data_count, bytes_written)
	register mach_device_t	device;
#endif
	ipc_port_t		reply_port;
	mach_msg_type_name_t	reply_port_type;
	dev_mode_t		mode;
	recnum_t		recnum;
	io_buf_ptr_t		data;
	unsigned int		data_count;
	int			*bytes_written;	/* out */
{
#ifdef i386
	register mach_device_t	device = d;
#endif
	register io_req_t	ior;
	register io_return_t	result;

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

#ifndef i386
	if (data == 0)
	   return (D_INVALID_SIZE);
#endif

	/*
	 * XXX Need logic to reject ridiculously big requests.
	 */

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * Package the write request for the device driver
	 */
	io_req_alloc(ior, data_count);

	ior->io_device		= device;
	ior->io_unit		= device->dev_number;
	ior->io_op		= IO_WRITE | IO_CALL;
	ior->io_mode		= mode;
	ior->io_recnum		= recnum;
	ior->io_data		= data;
	ior->io_count		= data_count;
	ior->io_total		= data_count;
	ior->io_alloc_size	= 0;
	ior->io_residual	= 0;
	ior->io_error		= 0;
	ior->io_done		= ds_write_done;
	ior->io_reply_port	= reply_port;
	ior->io_reply_port_type	= reply_port_type;
	ior->io_copy		= VM_MAP_COPY_NULL;

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * And do the write ...
	 *
	 * device_write_dealoc returns false if there's more
	 * to do; it has updated the ior appropriately and expects
	 * its caller to reinvoke it on the device.
	 */

	do {

		result = (*device->dev_ops->d_write)(device->dev_number, ior);

		/*
		 * If the IO was queued, delay reply until it is finished.
		 */
		if (result == D_IO_QUEUED)
		    return (MIG_NO_REPLY);

		/*
		 * Discard the local mapping of the data.
		 */

	} while (!device_write_dealloc(ior));

	/*
	 * Return the number of bytes actually written.
	 */
	*bytes_written = ior->io_total - ior->io_residual;

	/*
	 * Remove the extra reference.
	 */
	mach_device_deallocate(device);

	io_req_free(ior);
	return (result);
}

/*
 * Write to a device, but memory is in message.
 */
#ifdef i386
static io_return_t
device_write_inband(d, reply_port, reply_port_type, mode, recnum,
		    data, data_count, bytes_written)
	void *d;
#else
io_return_t
ds_device_write_inband(device, reply_port, reply_port_type, mode, recnum,
		       data, data_count, bytes_written)
	register mach_device_t	device;
#endif
	ipc_port_t		reply_port;
	mach_msg_type_name_t	reply_port_type;
	dev_mode_t		mode;
	recnum_t		recnum;
	io_buf_ptr_inband_t	data;
	unsigned int		data_count;
	int			*bytes_written; /* out */
{
#ifdef i386
	register mach_device_t	device = d;
#endif
	register io_req_t	ior;
	register io_return_t	result;

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

#ifndef i386
	if (data == 0)
	   return (D_INVALID_SIZE);
#endif

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * Package the write request for the device driver.
	 */
	io_req_alloc(ior, 0);

	ior->io_device		= device;
	ior->io_unit		= device->dev_number;
	ior->io_op		= IO_WRITE | IO_CALL | IO_INBAND;
	ior->io_mode		= mode;
	ior->io_recnum		= recnum;
	ior->io_data		= data;
	ior->io_count		= data_count;
	ior->io_total		= data_count;
	ior->io_alloc_size	= 0;
	ior->io_residual	= 0;
	ior->io_error		= 0;
	ior->io_done		= ds_write_done;
	ior->io_reply_port	= reply_port;
	ior->io_reply_port_type = reply_port_type;

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * And do the write.
	 */
	result = (*device->dev_ops->d_write)(device->dev_number, ior);

	/*
	 * If the IO was queued, delay reply until it is finished.
	 */
	if (result == D_IO_QUEUED)
	    return (MIG_NO_REPLY);

	/*
	 * Return the number of bytes actually written.
	 */
	*bytes_written = ior->io_total - ior->io_residual;

	/*
	 * Remove the extra reference.
	 */
	mach_device_deallocate(device);

	io_req_free(ior);
	return (result);
}

/*
 * Wire down incoming memory to give to device.
 */
kern_return_t
device_write_get(ior, wait)
	register io_req_t	ior;
	boolean_t		*wait;
{
	vm_map_copy_t		io_copy;
	vm_offset_t		new_addr;
	register kern_return_t	result;
	int			bsize;
	vm_size_t		min_size;

	/*
	 * By default, caller does not have to wait.
	 */
	*wait = FALSE;

	/*
	 * Nothing to do if no data.
	 */
	if (ior->io_count == 0)
	    return (KERN_SUCCESS);

	/*
	 * Loaned iors already have valid data.
	 */
	if (ior->io_op & IO_LOANED)
	    return (KERN_SUCCESS);

	/*
	 * Inband case.
	 */
	if (ior->io_op & IO_INBAND) {
	    assert(ior->io_count <= sizeof (io_buf_ptr_inband_t));
	    new_addr = zalloc(io_inband_zone);
	    memcpy((void*)new_addr, ior->io_data, ior->io_count);
	    ior->io_data = (io_buf_ptr_t)new_addr;
	    ior->io_alloc_size = sizeof (io_buf_ptr_inband_t);

	    return (KERN_SUCCESS);
	}

	/*
	 *	Figure out how much data to move this time.  If the device
	 *	won't return a block size, then we have to do the whole
	 *	request in one shot (ditto if this is a block fragment),
	 *	otherwise, move at least one block's worth.
	 */
	result = (*ior->io_device->dev_ops->d_dev_info)(
					ior->io_device->dev_number,
					D_INFO_BLOCK_SIZE,
					&bsize);

	if (result != KERN_SUCCESS || ior->io_count < (vm_size_t) bsize)
		min_size = (vm_size_t) ior->io_count;
	else
		min_size = (vm_size_t) bsize;

	/*
	 *	Map the pages from this page list into memory.
	 *	io_data records location of data.
	 *	io_alloc_size is the vm size of the region to deallocate.
	 */
	io_copy = (vm_map_copy_t) ior->io_data;
	result = kmem_io_map_copyout(device_io_map,
			(vm_offset_t*)&ior->io_data, &new_addr,
		        &ior->io_alloc_size, io_copy, min_size);
	if (result != KERN_SUCCESS)
	    return (result);

	if ((ior->io_data + ior->io_count) >
	    (((char *)new_addr) + ior->io_alloc_size)) {

		/*
		 *	Operation has to be split.  Reset io_count for how
		 *	much we can do this time.
		 */
		assert(vm_map_copy_has_cont(io_copy));
		assert(ior->io_count == io_copy->size);
		ior->io_count = ior->io_alloc_size -
			(ior->io_data - ((char *)new_addr));

		/*
		 *	Caller must wait synchronously.
		 */
		ior->io_op &= ~IO_CALL;
		*wait = TRUE;
	}

	ior->io_copy = io_copy;			/* vm_map_copy to discard */
	return (KERN_SUCCESS);
}

/*
 * Clean up memory allocated for IO.
 */
boolean_t
device_write_dealloc(ior)
	register io_req_t	ior;
{
	vm_map_copy_t	new_copy = VM_MAP_COPY_NULL;
	register
	vm_map_copy_t	io_copy;
	kern_return_t	result;
	vm_offset_t	size_to_do;
	int		bsize;

	if (ior->io_alloc_size == 0)
	    return (TRUE);

	/*
	 * Inband case.
	 */
	if (ior->io_op & IO_INBAND) {
	    zfree(io_inband_zone, (vm_offset_t)ior->io_data);

	    return (TRUE);
	}

	if ((io_copy = ior->io_copy) == VM_MAP_COPY_NULL)
	    return (TRUE);

	/*
	 *	To prevent a possible deadlock with the default pager,
	 *	we have to release space in the device_io_map before
	 *	we allocate any memory.  (Which vm_map_copy_invoke_cont
	 *	might do.)  See the discussion in ds_init.
	 */

	kmem_io_map_deallocate(device_io_map,
		     	 trunc_page(ior->io_data),
			(vm_size_t) ior->io_alloc_size);

	if (vm_map_copy_has_cont(io_copy)) {

		/*
		 *	Remember how much is left, then
		 *	invoke or abort the continuation.
		 */
		size_to_do = io_copy->size - ior->io_count;
		if (ior->io_error == 0) {
			vm_map_copy_invoke_cont(io_copy, &new_copy, &result);
		}
		else {
			vm_map_copy_abort_cont(io_copy);
			result = KERN_FAILURE;
		}

		if (result == KERN_SUCCESS && new_copy != VM_MAP_COPY_NULL) {
			register int	res;

			/*
			 *	We have a new continuation, reset the ior to
			 *	represent the remainder of the request.  Must
			 *	adjust the recnum because drivers assume
			 *	that the residual is zero.
			 */
			ior->io_op &= ~IO_DONE;
			ior->io_op |= IO_CALL;

			res = (*ior->io_device->dev_ops->d_dev_info)(
					ior->io_device->dev_number,
					D_INFO_BLOCK_SIZE,
					&bsize);

			if (res != D_SUCCESS)
				panic("device_write_dealloc: No block size");

			ior->io_recnum += ior->io_count/bsize;
			ior->io_count = new_copy->size;
		}
		else {

			/*
			 *	No continuation.  Add amount we didn't get
			 *	to into residual.
			 */
			ior->io_residual += size_to_do;
		}
	}

	/*
	 *	Clean up the state for the IO that just completed.
	 */
        vm_map_copy_discard(ior->io_copy);
	ior->io_copy = VM_MAP_COPY_NULL;
	ior->io_data = (char *) new_copy;

	/*
	 *	Return FALSE if there's more IO to do.
	 */

	return(new_copy == VM_MAP_COPY_NULL);
}

/*
 * Send write completion message to client, and discard the data.
 */
boolean_t
ds_write_done(ior)
	register io_req_t	ior;
{
	/*
	 *	device_write_dealloc discards the data that has been
	 *	written, but may decide that there is more to write.
	 */
	while (!device_write_dealloc(ior)) {
		register io_return_t	result;
		register mach_device_t	device;

		/*
		 *     More IO to do -- invoke it.
		 */
		device = ior->io_device;
		result = (*device->dev_ops->d_write)(device->dev_number, ior);

		/*
		 * If the IO was queued, return FALSE -- not done yet.
		 */
		if (result == D_IO_QUEUED)
		    return (FALSE);
	}

	/*
	 *	Now the write is really complete.  Send reply.
	 */

	if (IP_VALID(ior->io_reply_port)) {
	    (void) (*((ior->io_op & IO_INBAND) ?
		      ds_device_write_reply_inband :
		      ds_device_write_reply))(ior->io_reply_port,
					      ior->io_reply_port_type,
					      ior->io_error,
					      (int) (ior->io_total -
						     ior->io_residual));
	}
	mach_device_deallocate(ior->io_device);

	return (TRUE);
}

/*
 * Read from a device.
 */
#ifdef i386
static io_return_t
device_read(d, reply_port, reply_port_type, mode, recnum,
	    bytes_wanted, data, data_count)
	void *d;
#else
io_return_t
ds_device_read(device, reply_port, reply_port_type, mode, recnum,
	       bytes_wanted, data, data_count)
	register mach_device_t	device;
#endif
	ipc_port_t		reply_port;
	mach_msg_type_name_t	reply_port_type;
	dev_mode_t		mode;
	recnum_t		recnum;
	int			bytes_wanted;
	io_buf_ptr_t		*data;		/* out */
	unsigned int		*data_count;	/* out */
{
#ifdef i386
	register mach_device_t	device = d;
#endif
	register io_req_t	ior;
	register io_return_t	result;

#ifdef lint
	*data = *data;
	*data_count = *data_count;
#endif /* lint */

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * There must be a reply port.
	 */
	if (!IP_VALID(reply_port)) {
	    printf("ds_* invalid reply port\n");
	    Debugger("ds_* reply_port");
	    return (MIG_NO_REPLY);	/* no sense in doing anything */
	}

	/*
	 * Package the read request for the device driver
	 */
	io_req_alloc(ior, 0);

	ior->io_device		= device;
	ior->io_unit		= device->dev_number;
	ior->io_op		= IO_READ | IO_CALL;
	ior->io_mode		= mode;
	ior->io_recnum		= recnum;
	ior->io_data		= 0;		/* driver must allocate data */
	ior->io_count		= bytes_wanted;
	ior->io_alloc_size	= 0;		/* no data allocated yet */
	ior->io_residual	= 0;
	ior->io_error		= 0;
	ior->io_done		= ds_read_done;
	ior->io_reply_port	= reply_port;
	ior->io_reply_port_type	= reply_port_type;

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * And do the read.
	 */
	result = (*device->dev_ops->d_read)(device->dev_number, ior);

	/*
	 * If the IO was queued, delay reply until it is finished.
	 */
	if (result == D_IO_QUEUED)
	    return (MIG_NO_REPLY);

	/*
	 * Return result via ds_read_done.
	 */
	ior->io_error = result;
	(void) ds_read_done(ior);
	io_req_free(ior);

	return (MIG_NO_REPLY);	/* reply has already been sent. */
}

/*
 * Read from a device, but return the data 'inband.'
 */
#ifdef i386
static io_return_t
device_read_inband(d, reply_port, reply_port_type, mode, recnum,
		   bytes_wanted, data, data_count)
	void *d;
#else
io_return_t
ds_device_read_inband(device, reply_port, reply_port_type, mode, recnum,
		      bytes_wanted, data, data_count)
	register mach_device_t	device;
#endif
	ipc_port_t		reply_port;
	mach_msg_type_name_t	reply_port_type;
	dev_mode_t		mode;
	recnum_t		recnum;
	int			bytes_wanted;
	char			*data;		/* pointer to OUT array */
	unsigned int		*data_count;	/* out */
{
#ifdef i386
	register mach_device_t	device = d;
#endif
	register io_req_t	ior;
	register io_return_t	result;

#ifdef lint
	*data = *data;
	*data_count = *data_count;
#endif /* lint */

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * There must be a reply port.
	 */
	if (!IP_VALID(reply_port)) {
	    printf("ds_* invalid reply port\n");
	    Debugger("ds_* reply_port");
	    return (MIG_NO_REPLY);	/* no sense in doing anything */
	}

	/*
	 * Package the read for the device driver
	 */
	io_req_alloc(ior, 0);

	ior->io_device		= device;
	ior->io_unit		= device->dev_number;
	ior->io_op		= IO_READ | IO_CALL | IO_INBAND;
	ior->io_mode		= mode;
	ior->io_recnum		= recnum;
	ior->io_data		= 0;		/* driver must allocate data */
	ior->io_count		=
	    ((bytes_wanted < sizeof(io_buf_ptr_inband_t)) ?
		bytes_wanted : sizeof(io_buf_ptr_inband_t));
	ior->io_alloc_size	= 0;		/* no data allocated yet */
	ior->io_residual	= 0;
	ior->io_error		= 0;
	ior->io_done		= ds_read_done;
	ior->io_reply_port	= reply_port;
	ior->io_reply_port_type	= reply_port_type;

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * Do the read.
	 */
	result = (*device->dev_ops->d_read)(device->dev_number, ior);

	/*
	 * If the io was queued, delay reply until it is finished.
	 */
	if (result == D_IO_QUEUED)
	    return (MIG_NO_REPLY);

	/*
	 * Return result, via ds_read_done.
	 */
	ior->io_error = result;
	(void) ds_read_done(ior);
	io_req_free(ior);

	return (MIG_NO_REPLY);	/* reply has already been sent. */
}


/*
 * Allocate wired-down memory for device read.
 */
kern_return_t device_read_alloc(ior, size)
	register io_req_t	ior;
	register vm_size_t	size;
{
	vm_offset_t		addr;
	kern_return_t		kr;

	/*
	 * Nothing to do if no data.
	 */
	if (ior->io_count == 0)
	    return (KERN_SUCCESS);

	if (ior->io_op & IO_INBAND) {
	    ior->io_data = (io_buf_ptr_t) zalloc(io_inband_zone);
	    ior->io_alloc_size = sizeof(io_buf_ptr_inband_t);
	} else {
	    size = round_page(size);
	    kr = kmem_alloc(kernel_map, &addr, size);
	    if (kr != KERN_SUCCESS)
		return (kr);

	    ior->io_data = (io_buf_ptr_t) addr;
	    ior->io_alloc_size = size;
	}

	return (KERN_SUCCESS);
}

boolean_t ds_read_done(ior)
	io_req_t	ior;
{
	vm_offset_t		start_data, end_data;
	vm_offset_t		start_sent, end_sent;
	register vm_size_t	size_read;

	if (ior->io_error)
	    size_read = 0;
	else
	    size_read = ior->io_count - ior->io_residual;

	start_data  = (vm_offset_t)ior->io_data;
	end_data    = start_data + size_read;

	start_sent  = (ior->io_op & IO_INBAND) ? start_data :
						trunc_page(start_data);
	end_sent    = (ior->io_op & IO_INBAND) ?
		start_data + ior->io_alloc_size : round_page(end_data);

	/*
	 * Zero memory that the device did not fill.
	 */
	if (start_sent < start_data)
	    memset((char *)start_sent, 0, start_data - start_sent);
	if (end_sent > end_data)
	    memset((char *)end_data, 0, end_sent - end_data);


	/*
	 * Touch the data being returned, to mark it dirty.
	 * If the pages were filled by DMA, the pmap module
	 * may think that they are clean.
	 */
	{
	    register vm_offset_t	touch;
	    register int		c;

	    for (touch = start_sent; touch < end_sent; touch += PAGE_SIZE) {
		c = *(volatile char *)touch;
		*(volatile char *)touch = c;
	    }
	}

	/*
	 * Send the data to the reply port - this
	 * unwires and deallocates it.
	 */
	if (ior->io_op & IO_INBAND) {
	    (void)ds_device_read_reply_inband(ior->io_reply_port,
					      ior->io_reply_port_type,
					      ior->io_error,
					      (char *) start_data,
					      size_read);
	} else {
	    vm_map_copy_t copy;
	    kern_return_t kr;

	    kr = vm_map_copyin_page_list(kernel_map, start_data,
						 size_read, TRUE, TRUE,
						 &copy, FALSE);

	    if (kr != KERN_SUCCESS)
		panic("read_done: vm_map_copyin_page_list failed");

	    (void)ds_device_read_reply(ior->io_reply_port,
				       ior->io_reply_port_type,
				       ior->io_error,
				       (char *) copy,
				       size_read);
	}

	/*
	 * Free any memory that was allocated but not sent.
	 */
	if (ior->io_count != 0) {
	    if (ior->io_op & IO_INBAND) {
		if (ior->io_alloc_size > 0)
		    zfree(io_inband_zone, (vm_offset_t)ior->io_data);
	    } else {
		register vm_offset_t	end_alloc;

		end_alloc = start_sent + round_page(ior->io_alloc_size);
		if (end_alloc > end_sent)
		    (void) vm_deallocate(kernel_map,
					 end_sent,
					 end_alloc - end_sent);
	    }
	}

	mach_device_deallocate(ior->io_device);

	return (TRUE);
}

#ifdef i386
static io_return_t
device_set_status(d, flavor, status, status_count)
	void *d;
#else
io_return_t
ds_device_set_status(device, flavor, status, status_count)
	register mach_device_t	device;
#endif
	dev_flavor_t		flavor;
	dev_status_t		status;
	mach_msg_type_number_t	status_count;
{
#ifdef i386
	register mach_device_t device = d;
#endif

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	return ((*device->dev_ops->d_setstat)(device->dev_number,
					      flavor,
					      status,
					      status_count));
}

#ifdef i386
io_return_t
mach_device_get_status(d, flavor, status, status_count)
	void *d;
#else
io_return_t
ds_device_get_status(device, flavor, status, status_count)
	register mach_device_t	device;
#endif
	dev_flavor_t		flavor;
	dev_status_t		status;		/* pointer to OUT array */
	mach_msg_type_number_t	*status_count;	/* out */
{
#ifdef i386
	register mach_device_t	device = d;
#endif

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	return ((*device->dev_ops->d_getstat)(device->dev_number,
					      flavor,
					      status,
					      status_count));
}

#ifdef i386
static io_return_t
device_set_filter(d, receive_port, priority, filter, filter_count)
	void *d;
#else
io_return_t
ds_device_set_filter(device, receive_port, priority, filter, filter_count)
	register mach_device_t	device;
#endif
	ipc_port_t		receive_port;
	int			priority;
	filter_t		filter[];	/* pointer to IN array */
	unsigned int		filter_count;
{
#ifdef i386
	register mach_device_t	device = d;
#endif

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * Request is absurd if no receive port is specified.
	 */
	if (!IP_VALID(receive_port))
	    return (D_INVALID_OPERATION);

	return ((*device->dev_ops->d_async_in)(device->dev_number,
					       receive_port,
					       priority,
					       filter,
					       filter_count));
}

#ifdef i386
static io_return_t
device_map(d, protection, offset, size, pager, unmap)
	void *d;
#else
io_return_t
ds_device_map(device, protection, offset, size, pager, unmap)
	register mach_device_t	device;
#endif
	vm_prot_t		protection;
	vm_offset_t		offset;
	vm_size_t		size;
	ipc_port_t		*pager;	/* out */
	boolean_t		unmap;	/* ? */
{
#ifdef i386
	register mach_device_t device = d;
#endif

#ifdef	lint
	unmap = unmap;
#endif	/* lint */
	if (protection & ~VM_PROT_ALL)
		return (KERN_INVALID_ARGUMENT);

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
	    return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
	    return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	return (device_pager_setup(device, protection, offset, size,
				    (mach_port_t*)pager));
}

/*
 * Doesn't do anything (yet).
 */
#ifdef i386
static void
#else
void
#endif
ds_no_senders(notification)
	mach_no_senders_notification_t *notification;
{
	printf("ds_no_senders called! device_port=0x%x count=%d\n",
	       notification->not_header.msgh_remote_port,
	       notification->not_count);
}

#ifndef i386
boolean_t
ds_notify(msg)
	mach_msg_header_t *msg;
{
	switch (msg->msgh_id) {
		case MACH_NOTIFY_NO_SENDERS:
		ds_no_senders((mach_no_senders_notification_t *) msg);
		return TRUE;

		default:
		printf("ds_notify: strange notification %d\n", msg->msgh_id);
		return FALSE;
	}
}
#endif

queue_head_t		io_done_list;
decl_simple_lock_data(,	io_done_list_lock)

#define	splio	splsched	/* XXX must block ALL io devices */

void iodone(ior)
	register io_req_t	ior;
{
	register spl_t	s;

	/*
	 * If this ior was loaned to us, return it directly.
	 */
	if (ior->io_op & IO_LOANED) {
		(*ior->io_done)(ior);
		return;
	}
	/*
	 * If !IO_CALL, some thread is waiting for this.  Must lock
	 * structure to interlock correctly with iowait().  Else can
	 * toss on queue for io_done thread to call completion.
	 */
	s = splio();
	if ((ior->io_op & IO_CALL) == 0) {
	    ior_lock(ior);
	    ior->io_op |= IO_DONE;
	    ior->io_op &= ~IO_WANTED;
	    ior_unlock(ior);
	    thread_wakeup((event_t)ior);
	} else {
	    ior->io_op |= IO_DONE;
	    simple_lock(&io_done_list_lock);
	    enqueue_tail(&io_done_list, (queue_entry_t)ior);
	    thread_wakeup((event_t)&io_done_list);
	    simple_unlock(&io_done_list_lock);
	}
	splx(s);
}

void io_done_thread_continue()
{
	for (;;) {
	    register spl_t	s;
	    register io_req_t	ior;

#if defined (i386) && defined (LINUX_DEV) && defined (CONFIG_INET)
	    free_skbuffs ();
#endif
	    s = splio();
	    simple_lock(&io_done_list_lock);
	    while ((ior = (io_req_t)dequeue_head(&io_done_list)) != 0) {
		simple_unlock(&io_done_list_lock);
		(void) splx(s);

		if ((*ior->io_done)(ior)) {
		    /*
		     * IO done - free io_req_elt
		     */
		    io_req_free(ior);
		}
		/* else routine has re-queued it somewhere */

		s = splio();
		simple_lock(&io_done_list_lock);
	    }

	    assert_wait(&io_done_list, FALSE);
	    simple_unlock(&io_done_list_lock);
	    (void) splx(s);
	    counter(c_io_done_thread_block++);
	    thread_block(io_done_thread_continue);
	}
}

void io_done_thread()
{
	/*
	 * Set thread privileges and highest priority.
	 */
	current_thread()->vm_privilege = TRUE;
	stack_privilege(current_thread());
	thread_set_own_priority(0);

	io_done_thread_continue();
	/*NOTREACHED*/
}

#define	DEVICE_IO_MAP_SIZE	(2 * 1024 * 1024)

extern void ds_trap_init(void);		/* forward */

void ds_init()
{
	vm_offset_t	device_io_min, device_io_max;

	queue_init(&io_done_list);
	simple_lock_init(&io_done_list_lock);

	device_io_map = kmem_suballoc(kernel_map,
				      &device_io_min,
				      &device_io_max,
				      DEVICE_IO_MAP_SIZE,
				      FALSE);
	/*
	 *	If the kernel receives many device_write requests, the
	 *	device_io_map might run out of space.  To prevent
	 *	device_write_get from failing in this case, we enable
	 *	wait_for_space on the map.  This causes kmem_io_map_copyout
	 *	to block until there is sufficient space.
	 *	(XXX Large writes may be starved by small writes.)
	 *
	 *	There is a potential deadlock problem with this solution,
	 *	if a device_write from the default pager has to wait
	 *	for the completion of a device_write which needs to wait
	 *	for memory allocation.  Hence, once device_write_get
	 *	allocates space in device_io_map, no blocking memory
	 *	allocations should happen until device_write_dealloc
	 *	frees the space.  (XXX A large write might starve
	 *	a small write from the default pager.)
	 */
	device_io_map->wait_for_space = TRUE;

	io_inband_zone = zinit(sizeof(io_buf_ptr_inband_t),
			    1000 * sizeof(io_buf_ptr_inband_t),
			    10 * sizeof(io_buf_ptr_inband_t),
			    FALSE,
			    "io inband read buffers");

	ds_trap_init();
}

void iowait(ior)
    io_req_t ior;
{
    spl_t s;

    s = splio();
    ior_lock(ior);
    while ((ior->io_op&IO_DONE)==0) {
	assert_wait((event_t)ior, FALSE);
	ior_unlock(ior);
	thread_block((void (*)()) 0);
        ior_lock(ior);
    }
    ior_unlock(ior);
    splx(s);
}


/*
 * Device trap support.
 */

/*
 * Memory Management
 *
 * This currently has a single pool of 2k wired buffers
 * since we only handle writes to an ethernet device.
 * Should be more general.
 */
#define IOTRAP_REQSIZE 2048

zone_t io_trap_zone;

/*
 * Initialization.  Called from ds_init().
 */
void
ds_trap_init(void)
{
	io_trap_zone = zinit(IOTRAP_REQSIZE,
			     256 * IOTRAP_REQSIZE,
			     16 * IOTRAP_REQSIZE,
			     FALSE,
			     "wired device trap buffers");
}

/*
 * Allocate an io_req_t.
 * Currently zalloc's from io_trap_zone.
 *
 * Could have lists of different size zones.
 * Could call a device-specific routine.
 */
io_req_t
ds_trap_req_alloc(mach_device_t device, vm_size_t data_size)
{
	return (io_req_t) zalloc(io_trap_zone);
}

/*
 * Called by iodone to release ior.
 */
boolean_t
ds_trap_write_done(io_req_t ior)
{
	register mach_device_t dev;

	dev = ior->io_device;

	/*
	 * Should look at reply port and maybe send a message.
	 */
	zfree(io_trap_zone, (vm_offset_t) ior);

	/*
	 * Give up device reference from ds_write_trap.
	 */
	mach_device_deallocate(dev);
	return TRUE;
}

/*
 * Like device_write except that data is in user space.
 */
#ifdef i386
static io_return_t
device_write_trap (void *d, dev_mode_t mode,
		   recnum_t recnum, vm_offset_t data, vm_size_t data_count)
#else
io_return_t
ds_device_write_trap(device_t		device,
		     dev_mode_t		mode,
		     recnum_t		recnum,
		     vm_offset_t	data,
		     vm_size_t		data_count)
#endif
{
#ifdef i386
	mach_device_t device = d;
#endif
	io_req_t ior;
	io_return_t result;

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
		return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
		return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * Get a buffer to hold the ioreq.
	 */
	ior = ds_trap_req_alloc(device, data_count);

	/*
	 * Package the write request for the device driver.
	 */

	ior->io_device          = device;
	ior->io_unit            = device->dev_number;
	ior->io_op              = IO_WRITE | IO_CALL | IO_LOANED;
	ior->io_mode            = mode;
	ior->io_recnum          = recnum;
	ior->io_data            = (io_buf_ptr_t)
		(vm_offset_t)ior + sizeof(struct io_req);
	ior->io_count           = data_count;
	ior->io_total           = data_count;
	ior->io_alloc_size      = 0;
	ior->io_residual        = 0;
	ior->io_error           = 0;
	ior->io_done            = ds_trap_write_done;
	ior->io_reply_port      = IP_NULL;	/* XXX */
	ior->io_reply_port_type = 0;		/* XXX */

	/*
	 * Copy the data from user space.
	 */
	if (data_count > 0)
		copyin((char *)data, (char *)ior->io_data, data_count);

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * And do the write.
	 */
	result = (*device->dev_ops->d_write)(device->dev_number, ior);

	/*
	 * If the IO was queued, delay reply until it is finished.
	 */
	if (result == D_IO_QUEUED)
		return (MIG_NO_REPLY);

	/*
	 * Remove the extra reference.
	 */
	mach_device_deallocate(device);

	zfree(io_trap_zone, (vm_offset_t) ior);
	return (result);
}

#ifdef i386
static io_return_t
device_writev_trap (void *d, dev_mode_t mode,
		    recnum_t recnum, io_buf_vec_t *iovec, vm_size_t iocount)
#else
io_return_t
ds_device_writev_trap(device_t		device,
		      dev_mode_t	mode,
		      recnum_t		recnum,
		      io_buf_vec_t	*iovec,
		      vm_size_t		iocount)
#endif
{
#ifdef i386
	mach_device_t device = d;
#endif
	io_req_t ior;
	io_return_t result;
	io_buf_vec_t	stack_iovec[16]; /* XXX */
	vm_size_t data_count;
	int i;

#ifndef i386
	/*
	 * Refuse if device is dead or not completely open.
	 */
	if (device == DEVICE_NULL)
		return (D_NO_SUCH_DEVICE);
#endif

	if (device->state != DEV_STATE_OPEN)
		return (D_NO_SUCH_DEVICE);

	/* XXX note that a CLOSE may proceed at any point */

	/*
	 * Copyin user addresses.
	 */
	if (iocount > 16)
		return KERN_INVALID_VALUE; /* lame */
	copyin((char *)iovec,
	       (char *)stack_iovec,
	       iocount * sizeof(io_buf_vec_t));
	for (data_count = 0, i = 0; i < iocount; i++)
		data_count += stack_iovec[i].count;

	/*
	 * Get a buffer to hold the ioreq.
	 */
	ior = ds_trap_req_alloc(device, data_count);

	/*
	 * Package the write request for the device driver.
	 */

	ior->io_device          = device;
	ior->io_unit            = device->dev_number;
	ior->io_op              = IO_WRITE | IO_CALL | IO_LOANED;
	ior->io_mode            = mode;
	ior->io_recnum          = recnum;
	ior->io_data            = (io_buf_ptr_t)
		(vm_offset_t)ior + sizeof(struct io_req);
	ior->io_count           = data_count;
	ior->io_total           = data_count;
	ior->io_alloc_size      = 0;
	ior->io_residual        = 0;
	ior->io_error           = 0;
	ior->io_done            = ds_trap_write_done;
	ior->io_reply_port      = IP_NULL;	/* XXX */
	ior->io_reply_port_type = 0;		/* XXX */

	/*
	 * Copy the data from user space.
	 */
	if (data_count > 0) {
		vm_offset_t p;

		p = (vm_offset_t) ior->io_data;
		for (i = 0; i < iocount; i++) {
			copyin((char *) stack_iovec[i].data,
			       (char *) p,
			       stack_iovec[i].count);
			p += stack_iovec[i].count;
		}
	}

	/*
	 * The ior keeps an extra reference for the device.
	 */
	mach_device_reference(device);

	/*
	 * And do the write.
	 */
	result = (*device->dev_ops->d_write)(device->dev_number, ior);

	/*
	 * If the IO was queued, delay reply until it is finished.
	 */
	if (result == D_IO_QUEUED)
		return (MIG_NO_REPLY);

	/*
	 * Remove the extra reference.
	 */
	mach_device_deallocate(device);

	zfree(io_trap_zone, (vm_offset_t) ior);
	return (result);
}

#ifdef i386
struct device_emulation_ops mach_device_emulation_ops =
{
  mach_device_reference,
  mach_device_deallocate,
  mach_convert_device_to_port,
  device_open,
  device_close,
  device_write,
  device_write_inband,
  device_read,
  device_read_inband,
  device_set_status,
  mach_device_get_status,
  device_set_filter,
  device_map,
  ds_no_senders,
  device_write_trap,
  device_writev_trap
};
#endif