summaryrefslogtreecommitdiffstats
path: root/NetworkPkg/MnpDxe/MnpConfig.c
blob: 3a51210060d6aeab167c4b2f9631294c1ab96d1b (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
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
/** @file
  Implementation of Managed Network Protocol private services.

Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "MnpImpl.h"
#include "MnpVlan.h"

EFI_SERVICE_BINDING_PROTOCOL    mMnpServiceBindingProtocol = {
  MnpServiceBindingCreateChild,
  MnpServiceBindingDestroyChild
};

EFI_MANAGED_NETWORK_PROTOCOL    mMnpProtocolTemplate = {
  MnpGetModeData,
  MnpConfigure,
  MnpMcastIpToMac,
  MnpGroups,
  MnpTransmit,
  MnpReceive,
  MnpCancel,
  MnpPoll
};

EFI_MANAGED_NETWORK_CONFIG_DATA mMnpDefaultConfigData = {
  10000000,
  10000000,
  0,
  FALSE,
  FALSE,
  FALSE,
  FALSE,
  FALSE,
  FALSE,
  FALSE
};

/**
  Add Count of net buffers to MnpDeviceData->FreeNbufQue. The length of the net
  buffer is specified by MnpDeviceData->BufferLength.

  @param[in, out]  MnpDeviceData         Pointer to the MNP_DEVICE_DATA.
  @param[in]       Count                 Number of NET_BUFFERs to add.

  @retval EFI_SUCCESS           The specified amount of NET_BUFs are allocated
                                and added to MnpDeviceData->FreeNbufQue.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate a NET_BUF structure.

**/
EFI_STATUS
MnpAddFreeNbuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN     UINTN             Count
  )
{
  EFI_STATUS  Status;
  UINTN       Index;
  NET_BUF     *Nbuf;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);
  ASSERT ((Count > 0) && (MnpDeviceData->BufferLength > 0));

  Status = EFI_SUCCESS;
  for (Index = 0; Index < Count; Index++) {
    Nbuf = NetbufAlloc (MnpDeviceData->BufferLength + MnpDeviceData->PaddingSize);
    if (Nbuf == NULL) {
      DEBUG ((EFI_D_ERROR, "MnpAddFreeNbuf: NetBufAlloc failed.\n"));

      Status = EFI_OUT_OF_RESOURCES;
      break;
    }

    if (MnpDeviceData->PaddingSize > 0) {
      //
      // Pad padding bytes before the media header
      //
      NetbufAllocSpace (Nbuf, MnpDeviceData->PaddingSize, NET_BUF_TAIL);
      NetbufTrim (Nbuf, MnpDeviceData->PaddingSize, NET_BUF_HEAD);
    }

    NetbufQueAppend (&MnpDeviceData->FreeNbufQue, Nbuf);
  }

  MnpDeviceData->NbufCnt += Index;
  return Status;
}


/**
  Allocate a free NET_BUF from MnpDeviceData->FreeNbufQue. If there is none
  in the queue, first try to allocate some and add them into the queue, then
  fetch the NET_BUF from the updated FreeNbufQue.

  @param[in, out]  MnpDeviceData        Pointer to the MNP_DEVICE_DATA.

  @return     Pointer to the allocated free NET_BUF structure, if NULL the
              operation is failed.

**/
NET_BUF *
MnpAllocNbuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData
  )
{
  EFI_STATUS    Status;
  NET_BUF_QUEUE *FreeNbufQue;
  NET_BUF       *Nbuf;
  EFI_TPL       OldTpl;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  FreeNbufQue = &MnpDeviceData->FreeNbufQue;
  OldTpl      = gBS->RaiseTPL (TPL_NOTIFY);

  //
  // Check whether there are available buffers, or else try to add some.
  //
  if (FreeNbufQue->BufNum == 0) {
    if ((MnpDeviceData->NbufCnt + MNP_NET_BUFFER_INCREASEMENT) > MNP_MAX_NET_BUFFER_NUM) {
      DEBUG (
        (EFI_D_ERROR,
        "MnpAllocNbuf: The maximum NET_BUF size is reached for MNP driver instance %p.\n",
        MnpDeviceData)
        );

      Nbuf = NULL;
      goto ON_EXIT;
    }

    Status = MnpAddFreeNbuf (MnpDeviceData, MNP_NET_BUFFER_INCREASEMENT);
    if (EFI_ERROR (Status)) {
      DEBUG (
        (EFI_D_ERROR,
        "MnpAllocNbuf: Failed to add NET_BUFs into the FreeNbufQue, %r.\n",
        Status)
        );

      //
      // Don't return NULL, perhaps MnpAddFreeNbuf does add some NET_BUFs but
      // the amount is less than MNP_NET_BUFFER_INCREASEMENT.
      //
    }
  }

  Nbuf = NetbufQueRemove (FreeNbufQue);

  //
  // Increase the RefCnt.
  //
  if (Nbuf != NULL) {
    NET_GET_REF (Nbuf);
  }

ON_EXIT:
  gBS->RestoreTPL (OldTpl);

  return Nbuf;
}


/**
  Try to reclaim the Nbuf into the buffer pool.

  @param[in, out]  MnpDeviceData         Pointer to the mnp device context data.
  @param[in, out]  Nbuf                  Pointer to the NET_BUF to free.

**/
VOID
MnpFreeNbuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN OUT NET_BUF           *Nbuf
  )
{
  EFI_TPL  OldTpl;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);
  ASSERT (Nbuf->RefCnt > 1);

  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  NET_PUT_REF (Nbuf);

  if (Nbuf->RefCnt == 1) {
    //
    // Trim all buffer contained in the Nbuf, then append it to the NbufQue.
    //
    NetbufTrim (Nbuf, Nbuf->TotalSize, NET_BUF_TAIL);

    if (NetbufAllocSpace (Nbuf, NET_VLAN_TAG_LEN, NET_BUF_HEAD) != NULL) {
      //
      // There is space reserved for vlan tag in the head, reclaim it
      //
      NetbufTrim (Nbuf, NET_VLAN_TAG_LEN, NET_BUF_TAIL);
    }

    NetbufQueAppend (&MnpDeviceData->FreeNbufQue, Nbuf);
  }

  gBS->RestoreTPL (OldTpl);
}

/**
  Add Count of TX buffers to MnpDeviceData->AllTxBufList and MnpDeviceData->FreeTxBufList.
  The length of the buffer is specified by MnpDeviceData->BufferLength.

  @param[in, out]  MnpDeviceData         Pointer to the MNP_DEVICE_DATA.
  @param[in]       Count                 Number of TX buffers to add.

  @retval EFI_SUCCESS           The specified amount of TX buffers are allocated.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate a TX buffer.

**/
EFI_STATUS
MnpAddFreeTxBuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN     UINTN             Count
  )
{
  EFI_STATUS        Status;
  UINT32            Index;
  MNP_TX_BUF_WRAP   *TxBufWrap;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);
  ASSERT ((Count > 0) && (MnpDeviceData->BufferLength > 0));

  Status = EFI_SUCCESS;
  for (Index = 0; Index < Count; Index++) {
    TxBufWrap = (MNP_TX_BUF_WRAP*) AllocatePool (OFFSET_OF (MNP_TX_BUF_WRAP, TxBuf) + MnpDeviceData->BufferLength );
    if (TxBufWrap == NULL) {
      DEBUG ((EFI_D_ERROR, "MnpAddFreeTxBuf: TxBuf Alloc failed.\n"));

      Status = EFI_OUT_OF_RESOURCES;
      break;
    }
    DEBUG ((EFI_D_INFO, "MnpAddFreeTxBuf: Add TxBufWrap %p, TxBuf %p\n", TxBufWrap, TxBufWrap->TxBuf));
    TxBufWrap->Signature = MNP_TX_BUF_WRAP_SIGNATURE;
    TxBufWrap->InUse     = FALSE;
    InsertTailList (&MnpDeviceData->FreeTxBufList, &TxBufWrap->WrapEntry);
    InsertTailList (&MnpDeviceData->AllTxBufList, &TxBufWrap->AllEntry);
  }

  MnpDeviceData->TxBufCount += Index;
  return Status;
}

/**
  Allocate a free TX buffer from MnpDeviceData->FreeTxBufList. If there is none
  in the queue, first try to recycle some from SNP, then try to allocate some and add
  them into the queue, then fetch the NET_BUF from the updated FreeTxBufList.

  @param[in, out]  MnpDeviceData        Pointer to the MNP_DEVICE_DATA.

  @return     Pointer to the allocated free NET_BUF structure, if NULL the
              operation is failed.

**/
UINT8 *
MnpAllocTxBuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData
  )
{
  EFI_TPL           OldTpl;
  UINT8             *TxBuf;
  EFI_STATUS        Status;
  LIST_ENTRY        *Entry;
  MNP_TX_BUF_WRAP   *TxBufWrap;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);

  if (IsListEmpty (&MnpDeviceData->FreeTxBufList)) {
    //
    // First try to recycle some TX buffer from SNP
    //
    Status = MnpRecycleTxBuf (MnpDeviceData);
    if (EFI_ERROR (Status)) {
      TxBuf = NULL;
      goto ON_EXIT;
    }

    //
    // If still no free TX buffer, allocate more.
    //
    if (IsListEmpty (&MnpDeviceData->FreeTxBufList)) {
      if ((MnpDeviceData->TxBufCount + MNP_TX_BUFFER_INCREASEMENT) > MNP_MAX_TX_BUFFER_NUM) {
        DEBUG (
          (EFI_D_ERROR,
          "MnpAllocTxBuf: The maximum TxBuf size is reached for MNP driver instance %p.\n",
          MnpDeviceData)
          );

        TxBuf = NULL;
        goto ON_EXIT;
      }

      Status = MnpAddFreeTxBuf (MnpDeviceData, MNP_TX_BUFFER_INCREASEMENT);
      if (IsListEmpty (&MnpDeviceData->FreeTxBufList)) {
        DEBUG (
          (EFI_D_ERROR,
          "MnpAllocNbuf: Failed to add TxBuf into the FreeTxBufList, %r.\n",
          Status)
          );

        TxBuf = NULL;
        goto ON_EXIT;
      }
    }
  }

  ASSERT (!IsListEmpty (&MnpDeviceData->FreeTxBufList));
  Entry = MnpDeviceData->FreeTxBufList.ForwardLink;
  RemoveEntryList (MnpDeviceData->FreeTxBufList.ForwardLink);
  TxBufWrap = NET_LIST_USER_STRUCT_S (Entry, MNP_TX_BUF_WRAP, WrapEntry, MNP_TX_BUF_WRAP_SIGNATURE);
  TxBufWrap->InUse = TRUE;
  TxBuf = TxBufWrap->TxBuf;

ON_EXIT:
  gBS->RestoreTPL (OldTpl);

  return TxBuf;
}

/**
  Try to reclaim the TX buffer into the buffer pool.

  @param[in, out]  MnpDeviceData         Pointer to the mnp device context data.
  @param[in, out]  TxBuf                 Pointer to the TX buffer to free.

**/
VOID
MnpFreeTxBuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN OUT UINT8             *TxBuf
  )
{
  MNP_TX_BUF_WRAP   *TxBufWrap;
  EFI_TPL           OldTpl;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  if (TxBuf == NULL) {
    return;
  }

  TxBufWrap = NET_LIST_USER_STRUCT (TxBuf, MNP_TX_BUF_WRAP, TxBuf);
  if (TxBufWrap->Signature != MNP_TX_BUF_WRAP_SIGNATURE) {
    DEBUG (
      (EFI_D_ERROR,
      "MnpFreeTxBuf: Signature check failed in MnpFreeTxBuf.\n")
      );
    return;
  }

  if (!TxBufWrap->InUse) {
    DEBUG (
      (EFI_D_WARN,
      "MnpFreeTxBuf: Duplicated recycle report from SNP.\n")
      );
    return;
  }

  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
  InsertTailList (&MnpDeviceData->FreeTxBufList, &TxBufWrap->WrapEntry);
  TxBufWrap->InUse = FALSE;
  gBS->RestoreTPL (OldTpl);
}

/**
  Try to recycle all the transmitted buffer address from SNP.

  @param[in, out]  MnpDeviceData     Pointer to the mnp device context data.

  @retval EFI_SUCCESS             Successed to recyclethe transmitted buffer address.
  @retval Others                  Failed to recyclethe transmitted buffer address.

**/
EFI_STATUS
MnpRecycleTxBuf (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData
  )
{
  UINT8                         *TxBuf;
  EFI_SIMPLE_NETWORK_PROTOCOL   *Snp;
  EFI_STATUS                    Status;

  Snp = MnpDeviceData->Snp;
  ASSERT (Snp != NULL);

  do {
    TxBuf = NULL;
    Status = Snp->GetStatus (Snp, NULL, (VOID **) &TxBuf);
    if (EFI_ERROR (Status)) {
      return Status;
    }

    if (TxBuf != NULL) {
      MnpFreeTxBuf (MnpDeviceData, TxBuf);
    }
  } while (TxBuf != NULL);

  return EFI_SUCCESS;
}

/**
  Initialize the mnp device context data.

  @param[in, out]  MnpDeviceData      Pointer to the mnp device context data.
  @param[in]       ImageHandle        The driver image handle.
  @param[in]       ControllerHandle   Handle of device to bind driver to.

  @retval EFI_SUCCESS           The mnp service context is initialized.
  @retval EFI_UNSUPPORTED       ControllerHandle does not support Simple Network Protocol.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
MnpInitializeDeviceData (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN     EFI_HANDLE        ImageHandle,
  IN     EFI_HANDLE        ControllerHandle
  )
{
  EFI_STATUS                  Status;
  EFI_SIMPLE_NETWORK_PROTOCOL *Snp;
  EFI_SIMPLE_NETWORK_MODE     *SnpMode;

  MnpDeviceData->Signature        = MNP_DEVICE_DATA_SIGNATURE;
  MnpDeviceData->ImageHandle      = ImageHandle;
  MnpDeviceData->ControllerHandle = ControllerHandle;

  //
  // Copy the MNP Protocol interfaces from the template.
  //
  CopyMem (&MnpDeviceData->VlanConfig, &mVlanConfigProtocolTemplate, sizeof (EFI_VLAN_CONFIG_PROTOCOL));

  //
  // Open the Simple Network protocol.
  //
  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiSimpleNetworkProtocolGuid,
                  (VOID **) &Snp,
                  ImageHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  if (EFI_ERROR (Status)) {
    return EFI_UNSUPPORTED;
  }

  //
  // Get MTU from Snp.
  //
  SnpMode            = Snp->Mode;
  MnpDeviceData->Snp = Snp;

  //
  // Initialize the lists.
  //
  InitializeListHead (&MnpDeviceData->ServiceList);
  InitializeListHead (&MnpDeviceData->GroupAddressList);

  //
  // Get the buffer length used to allocate NET_BUF to hold data received
  // from SNP. Do this before fill the FreeNetBufQue.
  //
  //
  MnpDeviceData->BufferLength = SnpMode->MediaHeaderSize + NET_VLAN_TAG_LEN + SnpMode->MaxPacketSize + NET_ETHER_FCS_SIZE;

  //
  // Make sure the protocol headers immediately following the media header
  // 4-byte aligned, and also preserve additional space for VLAN tag
  //
  MnpDeviceData->PaddingSize = ((4 - SnpMode->MediaHeaderSize) & 0x3) + NET_VLAN_TAG_LEN;

  //
  // Initialize MAC string which will be used as VLAN configuration variable name
  //
  Status = NetLibGetMacString (ControllerHandle, ImageHandle, &MnpDeviceData->MacString);
  if (EFI_ERROR (Status)) {
    goto ERROR;
  }

  //
  // Initialize the FreeNetBufQue and pre-allocate some NET_BUFs.
  //
  NetbufQueInit (&MnpDeviceData->FreeNbufQue);
  Status = MnpAddFreeNbuf (MnpDeviceData, MNP_INIT_NET_BUFFER_NUM);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "MnpInitializeDeviceData: MnpAddFreeNbuf failed, %r.\n", Status));

    goto ERROR;
  }

  //
  // Get one NET_BUF from the FreeNbufQue for rx cache.
  //
  MnpDeviceData->RxNbufCache = MnpAllocNbuf (MnpDeviceData);
  NetbufAllocSpace (
    MnpDeviceData->RxNbufCache,
    MnpDeviceData->BufferLength,
    NET_BUF_TAIL
    );

  //
  // Allocate buffer pool for tx.
  //
  InitializeListHead (&MnpDeviceData->FreeTxBufList);
  InitializeListHead (&MnpDeviceData->AllTxBufList);
  MnpDeviceData->TxBufCount = 0;

  //
  // Create the system poll timer.
  //
  Status = gBS->CreateEvent (
                  EVT_NOTIFY_SIGNAL | EVT_TIMER,
                  TPL_CALLBACK,
                  MnpSystemPoll,
                  MnpDeviceData,
                  &MnpDeviceData->PollTimer
                  );
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "MnpInitializeDeviceData: CreateEvent for poll timer failed.\n"));

    goto ERROR;
  }

  //
  // Create the timer for packet timeout check.
  //
  Status = gBS->CreateEvent (
                  EVT_NOTIFY_SIGNAL | EVT_TIMER,
                  TPL_CALLBACK,
                  MnpCheckPacketTimeout,
                  MnpDeviceData,
                  &MnpDeviceData->TimeoutCheckTimer
                  );
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "MnpInitializeDeviceData: CreateEvent for packet timeout check failed.\n"));

    goto ERROR;
  }

  //
  // Create the timer for media detection.
  //
  Status = gBS->CreateEvent (
                  EVT_NOTIFY_SIGNAL | EVT_TIMER,
                  TPL_CALLBACK,
                  MnpCheckMediaStatus,
                  MnpDeviceData,
                  &MnpDeviceData->MediaDetectTimer
                  );
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "MnpInitializeDeviceData: CreateEvent for media detection failed.\n"));

    goto ERROR;
  }

ERROR:
  if (EFI_ERROR (Status)) {
    //
    // Free the dynamic allocated resources if necessary.
    //
    if (MnpDeviceData->MacString != NULL) {
      FreePool (MnpDeviceData->MacString);
    }

    if (MnpDeviceData->TimeoutCheckTimer != NULL) {
      gBS->CloseEvent (MnpDeviceData->TimeoutCheckTimer);
    }

    if (MnpDeviceData->MediaDetectTimer != NULL) {
      gBS->CloseEvent (MnpDeviceData->MediaDetectTimer);
    }

    if (MnpDeviceData->PollTimer != NULL) {
      gBS->CloseEvent (MnpDeviceData->PollTimer);
    }

    if (MnpDeviceData->RxNbufCache != NULL) {
      MnpFreeNbuf (MnpDeviceData, MnpDeviceData->RxNbufCache);
    }

    if (MnpDeviceData->FreeNbufQue.BufNum != 0) {
      NetbufQueFlush (&MnpDeviceData->FreeNbufQue);
    }

    //
    // Close the Simple Network Protocol.
    //
    gBS->CloseProtocol (
          ControllerHandle,
          &gEfiSimpleNetworkProtocolGuid,
          ImageHandle,
          ControllerHandle
          );
  }

  return Status;
}


/**
  Destroy the MNP device context data.

  @param[in, out]  MnpDeviceData      Pointer to the mnp device context data.
  @param[in]       ImageHandle        The driver image handle.

**/
VOID
MnpDestroyDeviceData (
  IN OUT MNP_DEVICE_DATA   *MnpDeviceData,
  IN     EFI_HANDLE        ImageHandle
  )
{
  LIST_ENTRY         *Entry;
  LIST_ENTRY         *NextEntry;
  MNP_TX_BUF_WRAP    *TxBufWrap;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  //
  // Free Vlan Config variable name string
  //
  if (MnpDeviceData->MacString != NULL) {
    FreePool (MnpDeviceData->MacString);
  }

  //
  // The GroupAddressList must be empty.
  //
  ASSERT (IsListEmpty (&MnpDeviceData->GroupAddressList));

  //
  // Close the event.
  //
  gBS->CloseEvent (MnpDeviceData->TimeoutCheckTimer);
  gBS->CloseEvent (MnpDeviceData->MediaDetectTimer);
  gBS->CloseEvent (MnpDeviceData->PollTimer);

  //
  // Free the Tx buffer pool.
  //
  NET_LIST_FOR_EACH_SAFE(Entry, NextEntry, &MnpDeviceData->AllTxBufList) {
    TxBufWrap = NET_LIST_USER_STRUCT (Entry, MNP_TX_BUF_WRAP, AllEntry);
    RemoveEntryList (Entry);
    FreePool (TxBufWrap);
    MnpDeviceData->TxBufCount--;
  }
  ASSERT (IsListEmpty (&MnpDeviceData->AllTxBufList));
  ASSERT (MnpDeviceData->TxBufCount == 0);

  //
  // Free the RxNbufCache.
  //
  MnpFreeNbuf (MnpDeviceData, MnpDeviceData->RxNbufCache);

  //
  // Flush the FreeNbufQue.
  //
  MnpDeviceData->NbufCnt -= MnpDeviceData->FreeNbufQue.BufNum;
  NetbufQueFlush (&MnpDeviceData->FreeNbufQue);

  //
  // Close the Simple Network Protocol.
  //
  gBS->CloseProtocol (
         MnpDeviceData->ControllerHandle,
         &gEfiSimpleNetworkProtocolGuid,
         ImageHandle,
         MnpDeviceData->ControllerHandle
         );
}


/**
  Create mnp service context data.

  @param[in]       MnpDeviceData      Pointer to the mnp device context data.
  @param[in]       VlanId             The VLAN ID.
  @param[in]       Priority           The VLAN priority. If VlanId is 0,
                                      Priority is ignored.

  @return A pointer to MNP_SERVICE_DATA or NULL if failed to create MNP service context.

**/
MNP_SERVICE_DATA *
MnpCreateServiceData (
  IN MNP_DEVICE_DATA     *MnpDeviceData,
  IN UINT16              VlanId,
  IN UINT8                Priority OPTIONAL
  )
{
  EFI_HANDLE                MnpServiceHandle;
  MNP_SERVICE_DATA          *MnpServiceData;
  EFI_STATUS                Status;
  EFI_SIMPLE_NETWORK_MODE   *SnpMode;
  EFI_VLAN_CONFIG_PROTOCOL  *VlanConfig;

  //
  // Initialize the Mnp Service Data.
  //
  MnpServiceData = AllocateZeroPool (sizeof (MNP_SERVICE_DATA));
  if (MnpServiceData == NULL) {
    DEBUG ((DEBUG_ERROR, "MnpCreateServiceData: Failed to allocate memory for the new Mnp Service Data.\n"));

    return NULL;
  }

  //
  // Add to MNP service list
  //
  InsertTailList (&MnpDeviceData->ServiceList, &MnpServiceData->Link);

  MnpServiceData->Signature     = MNP_SERVICE_DATA_SIGNATURE;
  MnpServiceData->MnpDeviceData = MnpDeviceData;

  //
  // Copy the ServiceBinding structure.
  //
  CopyMem (&MnpServiceData->ServiceBinding, &mMnpServiceBindingProtocol, sizeof (EFI_SERVICE_BINDING_PROTOCOL));

  //
  // Initialize the lists.
  //
  InitializeListHead (&MnpServiceData->ChildrenList);

  SnpMode = MnpDeviceData->Snp->Mode;
  if (VlanId != 0) {
    //
    // Create VLAN child handle
    //
    MnpServiceHandle = MnpCreateVlanChild (
                         MnpDeviceData->ImageHandle,
                         MnpDeviceData->ControllerHandle,
                         VlanId,
                         &MnpServiceData->DevicePath
                         );
    if (MnpServiceHandle == NULL) {
      DEBUG ((DEBUG_ERROR, "MnpCreateServiceData: Failed to create child handle.\n"));

      return NULL;
    }

    //
    // Open VLAN Config Protocol by child
    //
    Status = gBS->OpenProtocol (
                    MnpDeviceData->ControllerHandle,
                    &gEfiVlanConfigProtocolGuid,
                    (VOID **) &VlanConfig,
                    MnpDeviceData->ImageHandle,
                    MnpServiceHandle,
                    EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
                    );
    if (EFI_ERROR (Status)) {
      goto Exit;
    }

    //
    // Reduce MTU for VLAN device
    //
    MnpServiceData->Mtu = SnpMode->MaxPacketSize - NET_VLAN_TAG_LEN;
  } else {
    //
    // VlanId set to 0 means rx/tx untagged frame
    //
    MnpServiceHandle    = MnpDeviceData->ControllerHandle;
    MnpServiceData->Mtu = SnpMode->MaxPacketSize;
  }

  MnpServiceData->ServiceHandle = MnpServiceHandle;
  MnpServiceData->VlanId        = VlanId;
  MnpServiceData->Priority      = Priority;

  //
  // Install the MNP Service Binding Protocol
  //
  Status = gBS->InstallMultipleProtocolInterfaces (
                  &MnpServiceHandle,
                  &gEfiManagedNetworkServiceBindingProtocolGuid,
                  &MnpServiceData->ServiceBinding,
                  NULL
                  );

Exit:
  if (EFI_ERROR (Status)) {
    MnpDestroyServiceData (MnpServiceData);
    MnpServiceData = NULL;
  }

  return MnpServiceData;
}

/**
  Destroy the MNP service context data.

  @param[in, out]  MnpServiceData    Pointer to the mnp service context data.

  @retval EFI_SUCCESS           The mnp service context is destroyed.
  @retval Others                Errors as indicated.

**/
EFI_STATUS
MnpDestroyServiceData (
  IN OUT MNP_SERVICE_DATA    *MnpServiceData
  )
{
  EFI_STATUS  Status;

  //
  // Uninstall the MNP Service Binding Protocol
  //
  Status = gBS->UninstallMultipleProtocolInterfaces (
                  MnpServiceData->ServiceHandle,
                  &gEfiManagedNetworkServiceBindingProtocolGuid,
                  &MnpServiceData->ServiceBinding,
                  NULL
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  if (MnpServiceData->VlanId != 0) {
    //
    // Close VlanConfig Protocol opened by VLAN child handle
    //
    Status = gBS->CloseProtocol (
                    MnpServiceData->MnpDeviceData->ControllerHandle,
                    &gEfiVlanConfigProtocolGuid,
                    MnpServiceData->MnpDeviceData->ImageHandle,
                    MnpServiceData->ServiceHandle
                    );
    if (EFI_ERROR (Status)) {
      return Status;
    }

    //
    // Uninstall Device Path Protocol to destroy the VLAN child handle
    //
    Status = gBS->UninstallMultipleProtocolInterfaces (
                    MnpServiceData->ServiceHandle,
                    &gEfiDevicePathProtocolGuid,
                    MnpServiceData->DevicePath,
                    NULL
                    );
    if (EFI_ERROR (Status)) {
      return Status;
    }

    if (MnpServiceData->DevicePath != NULL) {
      FreePool (MnpServiceData->DevicePath);
    }
  }

  //
  // Remove from MnpDeviceData service list
  //
  RemoveEntryList (&MnpServiceData->Link);

  FreePool (MnpServiceData);

  return Status;
}

/**
  Callback function which provided by user to remove one node in NetDestroyLinkList process.

  @param[in]    Entry           The entry to be removed.
  @param[in]    Context         Pointer to the callback context corresponds to the Context in NetDestroyLinkList.

  @retval EFI_SUCCESS           The entry has been removed successfully.
  @retval Others                Fail to remove the entry.

**/
EFI_STATUS
EFIAPI
MnpDestoryChildEntry (
  IN LIST_ENTRY         *Entry,
  IN VOID               *Context
  )
{
  MNP_INSTANCE_DATA             *Instance;
  EFI_SERVICE_BINDING_PROTOCOL  *ServiceBinding;

  ServiceBinding = (EFI_SERVICE_BINDING_PROTOCOL *) Context;
  Instance = CR (Entry, MNP_INSTANCE_DATA, InstEntry, MNP_INSTANCE_DATA_SIGNATURE);
  return ServiceBinding->DestroyChild (ServiceBinding, Instance->Handle);
}

/**
  Destroy all child of the MNP service data.

  @param[in, out]  MnpServiceData    Pointer to the mnp service context data.

  @retval EFI_SUCCESS           All child are destroyed.
  @retval Others                Failed to destroy all child.

**/
EFI_STATUS
MnpDestroyServiceChild (
  IN OUT MNP_SERVICE_DATA    *MnpServiceData
  )
{
  LIST_ENTRY                         *List;
  EFI_STATUS                         Status;
  UINTN                              ListLength;

  List = &MnpServiceData->ChildrenList;

  Status = NetDestroyLinkList (
             List,
             MnpDestoryChildEntry,
             &MnpServiceData->ServiceBinding,
             &ListLength
             );
  if (EFI_ERROR (Status) || ListLength != 0) {
    return EFI_DEVICE_ERROR;
  }

  return EFI_SUCCESS;
}

/**
  Find the MNP Service Data for given VLAN ID.

  @param[in]  MnpDeviceData      Pointer to the mnp device context data.
  @param[in]  VlanId             The VLAN ID.

  @return A pointer to MNP_SERVICE_DATA or NULL if not found.

**/
MNP_SERVICE_DATA *
MnpFindServiceData (
  IN MNP_DEVICE_DATA     *MnpDeviceData,
  IN UINT16              VlanId
  )
{
  LIST_ENTRY        *Entry;
  MNP_SERVICE_DATA  *MnpServiceData;

  NET_LIST_FOR_EACH (Entry, &MnpDeviceData->ServiceList) {
    //
    // Check VLAN ID of each Mnp Service Data
    //
    MnpServiceData = MNP_SERVICE_DATA_FROM_LINK (Entry);
    if (MnpServiceData->VlanId == VlanId) {
      return MnpServiceData;
    }
  }

  return NULL;
}

/**
  Initialize the mnp instance context data.

  @param[in]       MnpServiceData   Pointer to the mnp service context data.
  @param[in, out]  Instance         Pointer to the mnp instance context data
                                    to initialize.

**/
VOID
MnpInitializeInstanceData (
  IN     MNP_SERVICE_DATA    *MnpServiceData,
  IN OUT MNP_INSTANCE_DATA   *Instance
  )
{
  NET_CHECK_SIGNATURE (MnpServiceData, MNP_SERVICE_DATA_SIGNATURE);
  ASSERT (Instance != NULL);

  //
  // Set the signature.
  //
  Instance->Signature = MNP_INSTANCE_DATA_SIGNATURE;

  //
  // Copy the MNP Protocol interfaces from the template.
  //
  CopyMem (&Instance->ManagedNetwork, &mMnpProtocolTemplate, sizeof (Instance->ManagedNetwork));

  //
  // Copy the default config data.
  //
  CopyMem (&Instance->ConfigData, &mMnpDefaultConfigData, sizeof (Instance->ConfigData));

  //
  // Initialize the lists.
  //
  InitializeListHead (&Instance->GroupCtrlBlkList);
  InitializeListHead (&Instance->RcvdPacketQueue);
  InitializeListHead (&Instance->RxDeliveredPacketQueue);

  //
  // Initialize the RxToken Map.
  //
  NetMapInit (&Instance->RxTokenMap);

  //
  // Save the MnpServiceData info.
  //
  Instance->MnpServiceData = MnpServiceData;
}


/**
  Check whether the token specified by Arg matches the token in Item.

  @param[in]  Map               Pointer to the NET_MAP.
  @param[in]  Item              Pointer to the NET_MAP_ITEM.
  @param[in]  Arg               Pointer to the Arg, it's a pointer to the token to
                                check.

  @retval EFI_SUCCESS           The token specified by Arg is different from the
                                token in Item.
  @retval EFI_ACCESS_DENIED     The token specified by Arg is the same as that in
                                Item.

**/
EFI_STATUS
EFIAPI
MnpTokenExist (
  IN NET_MAP         *Map,
  IN NET_MAP_ITEM    *Item,
  IN VOID            *Arg
  )
{
  EFI_MANAGED_NETWORK_COMPLETION_TOKEN  *Token;
  EFI_MANAGED_NETWORK_COMPLETION_TOKEN  *TokenInItem;

  Token       = (EFI_MANAGED_NETWORK_COMPLETION_TOKEN *) Arg;
  TokenInItem = (EFI_MANAGED_NETWORK_COMPLETION_TOKEN *) Item->Key;

  if ((Token == TokenInItem) || (Token->Event == TokenInItem->Event)) {
    //
    // The token is the same either the two tokens equals or the Events in
    // the two tokens are the same.
    //
    return EFI_ACCESS_DENIED;
  }

  return EFI_SUCCESS;
}

/**
  Cancel the token specified by Arg if it matches the token in Item.

  @param[in, out]  Map               Pointer to the NET_MAP.
  @param[in, out]  Item              Pointer to the NET_MAP_ITEM.
  @param[in]       Arg               Pointer to the Arg, it's a pointer to the
                                     token to cancel.

  @retval EFI_SUCCESS       The Arg is NULL, and the token in Item is cancelled,
                            or the Arg isn't NULL, and the token in Item is
                            different from the Arg.
  @retval EFI_ABORTED       The Arg isn't NULL, the token in Item mathces the
                            Arg, and the token is cancelled.

**/
EFI_STATUS
EFIAPI
MnpCancelTokens (
  IN OUT NET_MAP         *Map,
  IN OUT NET_MAP_ITEM    *Item,
  IN     VOID            *Arg
  )
{
  EFI_MANAGED_NETWORK_COMPLETION_TOKEN  *TokenToCancel;

  if ((Arg != NULL) && (Item->Key != Arg)) {
    //
    // The token in Item is not the token specified by Arg.
    //
    return EFI_SUCCESS;
  }

  TokenToCancel = (EFI_MANAGED_NETWORK_COMPLETION_TOKEN *) Item->Key;

  //
  // Remove the item from the map.
  //
  NetMapRemoveItem (Map, Item, NULL);

  //
  // Cancel this token with status set to EFI_ABORTED.
  //
  TokenToCancel->Status = EFI_ABORTED;
  gBS->SignalEvent (TokenToCancel->Event);

  if (Arg != NULL) {
    //
    // Only abort the token specified by Arg if Arg isn't NULL.
    //
    return EFI_ABORTED;
  }

  return EFI_SUCCESS;
}


/**
  Start and initialize the simple network.

  @param[in]  Snp               Pointer to the simple network protocol.

  @retval EFI_SUCCESS           The simple network protocol is started.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
MnpStartSnp (
  IN EFI_SIMPLE_NETWORK_PROTOCOL     *Snp
  )
{
  EFI_STATUS  Status;

  ASSERT (Snp != NULL);

  //
  // Start the simple network.
  //
  Status = Snp->Start (Snp);

  if (!EFI_ERROR (Status)) {
    //
    // Initialize the simple network.
    //
    Status = Snp->Initialize (Snp, 0, 0);
  }

  return Status;
}


/**
  Stop the simple network.

  @param[in]  MnpDeviceData     Pointer to the MNP_DEVICE_DATA.

  @retval EFI_SUCCESS           The simple network is stopped.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
MnpStopSnp (
  IN  MNP_DEVICE_DATA   *MnpDeviceData
  )
{
  EFI_STATUS  Status;
  EFI_SIMPLE_NETWORK_PROTOCOL     *Snp;

  Snp = MnpDeviceData->Snp;
  ASSERT (Snp != NULL);

  //
  // Recycle all the transmit buffer from SNP.
  //
  Status = MnpRecycleTxBuf (MnpDeviceData);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Shut down the simple network.
  //
  Status  = Snp->Shutdown (Snp);
  if (!EFI_ERROR (Status)) {
    //
    // Stop the simple network.
    //
    Status = Snp->Stop (Snp);
  }

  return Status;
}


/**
  Start the managed network, this function is called when one instance is configured
  or reconfigured.

  @param[in, out]  MnpServiceData       Pointer to the mnp service context data.
  @param[in]       IsConfigUpdate       The instance is reconfigured or it's the first
                                        time the instanced is configured.
  @param[in]       EnableSystemPoll     Enable the system polling or not.

  @retval EFI_SUCCESS                   The managed network is started and some
                                        configuration is updated.
  @retval Others                        Other errors as indicated.

**/
EFI_STATUS
MnpStart (
  IN OUT MNP_SERVICE_DATA    *MnpServiceData,
  IN     BOOLEAN             IsConfigUpdate,
  IN     BOOLEAN             EnableSystemPoll
  )
{
  EFI_STATUS      Status;
  EFI_TIMER_DELAY TimerOpType;
  MNP_DEVICE_DATA *MnpDeviceData;

  NET_CHECK_SIGNATURE (MnpServiceData, MNP_SERVICE_DATA_SIGNATURE);

  Status        = EFI_SUCCESS;
  MnpDeviceData = MnpServiceData->MnpDeviceData;

  if (!IsConfigUpdate) {
    //
    // If it's not a configuration update, increase the configured children number.
    //
    MnpDeviceData->ConfiguredChildrenNumber++;

    if (MnpDeviceData->ConfiguredChildrenNumber == 1) {
      //
      // It's the first configured child, start the simple network.
      //
      Status = MnpStartSnp (MnpDeviceData->Snp);
      if (EFI_ERROR (Status)) {
        DEBUG ((EFI_D_ERROR, "MnpStart: MnpStartSnp failed, %r.\n", Status));

        goto ErrorExit;
      }

      //
      // Start the timeout timer.
      //
      Status = gBS->SetTimer (
                      MnpDeviceData->TimeoutCheckTimer,
                      TimerPeriodic,
                      MNP_TIMEOUT_CHECK_INTERVAL
                      );
      if (EFI_ERROR (Status)) {
        DEBUG (
          (EFI_D_ERROR,
          "MnpStart, gBS->SetTimer for TimeoutCheckTimer %r.\n",
          Status)
          );

        goto ErrorExit;
      }

      //
      // Start the media detection timer.
      //
      Status = gBS->SetTimer (
                      MnpDeviceData->MediaDetectTimer,
                      TimerPeriodic,
                      MNP_MEDIA_DETECT_INTERVAL
                      );
      if (EFI_ERROR (Status)) {
        DEBUG (
          (EFI_D_ERROR,
          "MnpStart, gBS->SetTimer for MediaDetectTimer %r.\n",
          Status)
          );

        goto ErrorExit;
      }
    }
  }

  if (MnpDeviceData->EnableSystemPoll ^ EnableSystemPoll) {
    //
    // The EnableSystemPoll differs with the current state, disable or enable
    // the system poll.
    //
    TimerOpType = EnableSystemPoll ? TimerPeriodic : TimerCancel;

    Status      = gBS->SetTimer (MnpDeviceData->PollTimer, TimerOpType, MNP_SYS_POLL_INTERVAL);
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_ERROR, "MnpStart: gBS->SetTimer for PollTimer failed, %r.\n", Status));

      goto ErrorExit;
    }

    MnpDeviceData->EnableSystemPoll = EnableSystemPoll;
  }

  //
  // Change the receive filters if need.
  //
  Status = MnpConfigReceiveFilters (MnpDeviceData);

ErrorExit:
  return Status;
}


/**
  Stop the managed network.

  @param[in, out]  MnpServiceData    Pointer to the mnp service context data.

  @retval EFI_SUCCESS                The managed network is stopped.
  @retval Others                     Other errors as indicated.

**/
EFI_STATUS
MnpStop (
  IN OUT MNP_SERVICE_DATA    *MnpServiceData
  )
{
  EFI_STATUS      Status;
  MNP_DEVICE_DATA *MnpDeviceData;

  NET_CHECK_SIGNATURE (MnpServiceData, MNP_SERVICE_DATA_SIGNATURE);
  MnpDeviceData = MnpServiceData->MnpDeviceData;
  ASSERT (MnpDeviceData->ConfiguredChildrenNumber > 0);

  //
  // Configure the receive filters.
  //
  MnpConfigReceiveFilters (MnpDeviceData);

  //
  // Decrease the children number.
  //
  MnpDeviceData->ConfiguredChildrenNumber--;

  if (MnpDeviceData->ConfiguredChildrenNumber > 0) {
    //
    // If there are other configured children, return and keep the timers and
    // simple network unchanged.
    //
    return EFI_SUCCESS;
  }

  //
  // No configured children now.
  //
  if (MnpDeviceData->EnableSystemPoll) {
    //
    //  The system poll in on, cancel the poll timer.
    //
    Status  = gBS->SetTimer (MnpDeviceData->PollTimer, TimerCancel, 0);
    MnpDeviceData->EnableSystemPoll = FALSE;
  }

  //
  // Cancel the timeout timer.
  //
  Status = gBS->SetTimer (MnpDeviceData->TimeoutCheckTimer, TimerCancel, 0);

  //
  // Cancel the media detect timer.
  //
  Status = gBS->SetTimer (MnpDeviceData->MediaDetectTimer, TimerCancel, 0);

  //
  // Stop the simple network.
  //
  Status = MnpStopSnp (MnpDeviceData);
  return Status;
}


/**
  Flush the instance's received data.

  @param[in, out]  Instance              Pointer to the mnp instance context data.

**/
VOID
MnpFlushRcvdDataQueue (
  IN OUT MNP_INSTANCE_DATA   *Instance
  )
{
  EFI_TPL         OldTpl;
  MNP_RXDATA_WRAP *RxDataWrap;

  NET_CHECK_SIGNATURE (Instance, MNP_INSTANCE_DATA_SIGNATURE);

  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  while (!IsListEmpty (&Instance->RcvdPacketQueue)) {
    //
    // Remove all the Wraps.
    //
    RxDataWrap = NET_LIST_HEAD (&Instance->RcvdPacketQueue, MNP_RXDATA_WRAP, WrapEntry);

    //
    // Recycle the RxDataWrap.
    //
    MnpRecycleRxData (NULL, (VOID *) RxDataWrap);
    Instance->RcvdPacketQueueSize--;
  }

  ASSERT (Instance->RcvdPacketQueueSize == 0);

  gBS->RestoreTPL (OldTpl);
}


/**
  Configure the Instance using ConfigData.

  @param[in, out]  Instance     Pointer to the mnp instance context data.
  @param[in]       ConfigData   Pointer to the configuration data used to configure
                                the instance.

  @retval EFI_SUCCESS           The Instance is configured.
  @retval EFI_UNSUPPORTED       EnableReceiveTimestamps is on and the
                                implementation doesn't support it.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
MnpConfigureInstance (
  IN OUT MNP_INSTANCE_DATA                 *Instance,
  IN     EFI_MANAGED_NETWORK_CONFIG_DATA   *ConfigData OPTIONAL
  )
{
  EFI_STATUS                      Status;
  MNP_SERVICE_DATA                *MnpServiceData;
  MNP_DEVICE_DATA                 *MnpDeviceData;
  EFI_MANAGED_NETWORK_CONFIG_DATA *OldConfigData;
  EFI_MANAGED_NETWORK_CONFIG_DATA *NewConfigData;
  BOOLEAN                         IsConfigUpdate;

  NET_CHECK_SIGNATURE (Instance, MNP_INSTANCE_DATA_SIGNATURE);

  if ((ConfigData != NULL) && ConfigData->EnableReceiveTimestamps) {
    //
    // Don't support timestamp.
    //
    return EFI_UNSUPPORTED;
  }

  Status          = EFI_SUCCESS;

  MnpServiceData  = Instance->MnpServiceData;
  MnpDeviceData   = MnpServiceData->MnpDeviceData;
  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  IsConfigUpdate  = (BOOLEAN) ((Instance->Configured) && (ConfigData != NULL));

  OldConfigData   = &Instance->ConfigData;
  NewConfigData   = ConfigData;
  if (NewConfigData == NULL) {
    //
    // Restore back the default config data if a reset of this instance
    // is required.
    //
    NewConfigData = &mMnpDefaultConfigData;
  }

  //
  // Reset the instance's receive filter.
  //
  Instance->ReceiveFilter = 0;

  //
  // Clear the receive counters according to the old ConfigData.
  //
  if (OldConfigData->EnableUnicastReceive) {
    MnpDeviceData->UnicastCount--;
  }

  if (OldConfigData->EnableMulticastReceive) {
    MnpDeviceData->MulticastCount--;
  }

  if (OldConfigData->EnableBroadcastReceive) {
    MnpDeviceData->BroadcastCount--;
  }

  if (OldConfigData->EnablePromiscuousReceive) {
    MnpDeviceData->PromiscuousCount--;
  }

  //
  // Set the receive filter counters and the receive filter of the
  // instance according to the new ConfigData.
  //
  if (NewConfigData->EnableUnicastReceive) {
    MnpDeviceData->UnicastCount++;
    Instance->ReceiveFilter |= MNP_RECEIVE_UNICAST;
  }

  if (NewConfigData->EnableMulticastReceive) {
    MnpDeviceData->MulticastCount++;
  }

  if (NewConfigData->EnableBroadcastReceive) {
    MnpDeviceData->BroadcastCount++;
    Instance->ReceiveFilter |= MNP_RECEIVE_BROADCAST;
  }

  if (NewConfigData->EnablePromiscuousReceive) {
    MnpDeviceData->PromiscuousCount++;
  }

  if (OldConfigData->FlushQueuesOnReset) {
    MnpFlushRcvdDataQueue (Instance);
  }

  if (ConfigData == NULL) {
    Instance->ManagedNetwork.Cancel (&Instance->ManagedNetwork, NULL);
  }

  if (!NewConfigData->EnableMulticastReceive) {
    MnpGroupOp (Instance, FALSE, NULL, NULL);
  }

  //
  // Save the new configuration data.
  //
  CopyMem (OldConfigData, NewConfigData, sizeof (*OldConfigData));

  Instance->Configured = (BOOLEAN) (ConfigData != NULL);
  if (Instance->Configured) {
    //
    // The instance is configured, start the Mnp.
    //
    Status = MnpStart (
              MnpServiceData,
              IsConfigUpdate,
              (BOOLEAN) !NewConfigData->DisableBackgroundPolling
              );
  } else {
    //
    // The instance is changed to the unconfigured state, stop the Mnp.
    //
    Status = MnpStop (MnpServiceData);
  }

  return Status;
}

/**
  Configure the Snp receive filters according to the instances' receive filter
  settings.

  @param[in]  MnpDeviceData         Pointer to the mnp device context data.

  @retval     EFI_SUCCESS           The receive filters is configured.
  @retval     EFI_OUT_OF_RESOURCES  The receive filters can't be configured due
                                    to lack of memory resource.

**/
EFI_STATUS
MnpConfigReceiveFilters (
  IN MNP_DEVICE_DATA     *MnpDeviceData
  )
{
  EFI_STATUS                  Status;
  EFI_SIMPLE_NETWORK_PROTOCOL *Snp;
  EFI_MAC_ADDRESS             *MCastFilter;
  UINT32                      MCastFilterCnt;
  UINT32                      EnableFilterBits;
  UINT32                      DisableFilterBits;
  BOOLEAN                     ResetMCastFilters;
  LIST_ENTRY                  *Entry;
  UINT32                      Index;
  MNP_GROUP_ADDRESS           *GroupAddress;

  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  Snp = MnpDeviceData->Snp;

  //
  // Initialize the enable filter and disable filter.
  //
  EnableFilterBits  = 0;
  DisableFilterBits = Snp->Mode->ReceiveFilterMask;

  if (MnpDeviceData->UnicastCount != 0) {
    //
    // Enable unicast if any instance wants to receive unicast.
    //
    EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_UNICAST;
  }

  if (MnpDeviceData->BroadcastCount != 0) {
    //
    // Enable broadcast if any instance wants to receive broadcast.
    //
    EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_BROADCAST;
  }

  MCastFilter       = NULL;
  MCastFilterCnt    = 0;
  ResetMCastFilters = TRUE;

  if ((MnpDeviceData->MulticastCount != 0) && (MnpDeviceData->GroupAddressCount != 0)) {
    //
    // There are instances configured to receive multicast and already some group
    // addresses are joined.
    //

    ResetMCastFilters = FALSE;

    if (MnpDeviceData->GroupAddressCount <= Snp->Mode->MaxMCastFilterCount) {
      //
      // The joind group address is less than simple network's maximum count.
      // Just configure the snp to do the multicast filtering.
      //

      EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_MULTICAST;

      //
      // Allocate pool for the multicast addresses.
      //
      MCastFilterCnt  = MnpDeviceData->GroupAddressCount;
      MCastFilter     = AllocatePool (sizeof (EFI_MAC_ADDRESS) * MCastFilterCnt);
      if (MCastFilter == NULL) {
        DEBUG ((EFI_D_ERROR, "MnpConfigReceiveFilters: Failed to allocate memory resource for MCastFilter.\n"));

        return EFI_OUT_OF_RESOURCES;
      }

      //
      // Fill the multicast HW address buffer.
      //
      Index = 0;
      NET_LIST_FOR_EACH (Entry, &MnpDeviceData->GroupAddressList) {

        GroupAddress = NET_LIST_USER_STRUCT (Entry, MNP_GROUP_ADDRESS, AddrEntry);
        CopyMem (MCastFilter + Index, &GroupAddress->Address, sizeof (*(MCastFilter + Index)));
        Index++;

        ASSERT (Index <= MCastFilterCnt);
      }
    } else {
      //
      // The maximum multicast is reached, set the filter to be promiscuous
      // multicast.
      //

      if ((Snp->Mode->ReceiveFilterMask & EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST) != 0) {
        EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST;
      } else {
        //
        // Either MULTICAST or PROMISCUOUS_MULTICAST is not supported by Snp,
        // set the NIC to be promiscuous although this will tremendously degrade
        // the performance.
        //
        EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS;
      }
    }
  }

  if (MnpDeviceData->PromiscuousCount != 0) {
    //
    // Enable promiscuous if any instance wants to receive promiscuous.
    //
    EnableFilterBits |= EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS;
  }

  //
  // Set the disable filter.
  //
  DisableFilterBits ^= EnableFilterBits;

  //
  // Configure the receive filters of SNP.
  //
  Status = Snp->ReceiveFilters (
                  Snp,
                  EnableFilterBits,
                  DisableFilterBits,
                  ResetMCastFilters,
                  MCastFilterCnt,
                  MCastFilter
                  );
  DEBUG_CODE (
    if (EFI_ERROR (Status)) {
      DEBUG (
        (EFI_D_ERROR,
        "MnpConfigReceiveFilters: Snp->ReceiveFilters failed, %r.\n",
        Status)
        );
    }
  );

  if (MCastFilter != NULL) {
    //
    // Free the buffer used to hold the group addresses.
    //
    FreePool (MCastFilter);
  }

  return Status;
}


/**
  Add a group address control block which controls the MacAddress for
  this instance.

  @param[in, out]  Instance        Pointer to the mnp instance context data.
  @param[in, out]  CtrlBlk         Pointer to the group address control block.
  @param[in, out]  GroupAddress    Pointer to the group address.
  @param[in]       MacAddress      Pointer to the mac address.
  @param[in]       HwAddressSize   The hardware address size.

  @retval EFI_SUCCESS              The group address control block is added.
  @retval EFI_OUT_OF_RESOURCES     Failed due to lack of memory resources.

**/
EFI_STATUS
MnpGroupOpAddCtrlBlk (
  IN OUT MNP_INSTANCE_DATA         *Instance,
  IN OUT MNP_GROUP_CONTROL_BLOCK   *CtrlBlk,
  IN OUT MNP_GROUP_ADDRESS         *GroupAddress OPTIONAL,
  IN     EFI_MAC_ADDRESS           *MacAddress,
  IN     UINT32                    HwAddressSize
  )
{
  MNP_DEVICE_DATA  *MnpDeviceData;

  NET_CHECK_SIGNATURE (Instance, MNP_INSTANCE_DATA_SIGNATURE);

  MnpDeviceData = Instance->MnpServiceData->MnpDeviceData;
  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  if (GroupAddress == NULL) {
    ASSERT (MacAddress != NULL);

    //
    // Allocate a new GroupAddress to be added into MNP's GroupAddressList.
    //
    GroupAddress = AllocatePool (sizeof (MNP_GROUP_ADDRESS));
    if (GroupAddress == NULL) {

      DEBUG ((EFI_D_ERROR, "MnpGroupOpFormCtrlBlk: Failed to allocate memory resource.\n"));

      return EFI_OUT_OF_RESOURCES;
    }

    CopyMem (&GroupAddress->Address, MacAddress, sizeof (GroupAddress->Address));
    GroupAddress->RefCnt = 0;
    InsertTailList (
      &MnpDeviceData->GroupAddressList,
      &GroupAddress->AddrEntry
      );
    MnpDeviceData->GroupAddressCount++;
  }

  //
  // Increase the RefCnt.
  //
  GroupAddress->RefCnt++;

  //
  // Add the CtrlBlk into the instance's GroupCtrlBlkList.
  //
  CtrlBlk->GroupAddress = GroupAddress;
  InsertTailList (&Instance->GroupCtrlBlkList, &CtrlBlk->CtrlBlkEntry);

  return EFI_SUCCESS;
}


/**
  Delete a group control block from the instance. If the controlled group address's
  reference count reaches zero, the group address is removed too.

  @param[in]  Instance              Pointer to the instance context data.
  @param[in]  CtrlBlk               Pointer to the group control block to delete.

  @return The group address controlled by the control block is no longer used or not.

**/
BOOLEAN
MnpGroupOpDelCtrlBlk (
  IN MNP_INSTANCE_DATA           *Instance,
  IN MNP_GROUP_CONTROL_BLOCK     *CtrlBlk
  )
{
  MNP_DEVICE_DATA   *MnpDeviceData;
  MNP_GROUP_ADDRESS *GroupAddress;

  NET_CHECK_SIGNATURE (Instance, MNP_INSTANCE_DATA_SIGNATURE);

  MnpDeviceData = Instance->MnpServiceData->MnpDeviceData;
  NET_CHECK_SIGNATURE (MnpDeviceData, MNP_DEVICE_DATA_SIGNATURE);

  //
  // Remove and free the CtrlBlk.
  //
  GroupAddress = CtrlBlk->GroupAddress;
  RemoveEntryList (&CtrlBlk->CtrlBlkEntry);
  FreePool (CtrlBlk);

  ASSERT (GroupAddress->RefCnt > 0);

  //
  // Count down the RefCnt.
  //
  GroupAddress->RefCnt--;

  if (GroupAddress->RefCnt == 0) {
    //
    // Free this GroupAddress entry if no instance uses it.
    //
    MnpDeviceData->GroupAddressCount--;
    RemoveEntryList (&GroupAddress->AddrEntry);
    FreePool (GroupAddress);

    return TRUE;
  }

  return FALSE;
}


/**
  Do the group operations for this instance.

  @param[in, out]  Instance        Pointer to the instance context data.
  @param[in]       JoinFlag        Set to TRUE to join a group. Set to TRUE to
                                   leave a group/groups.
  @param[in]       MacAddress      Pointer to the group address to join or leave.
  @param[in]       CtrlBlk         Pointer to the group control block if JoinFlag
                                   is FALSE.

  @retval EFI_SUCCESS              The group operation finished.
  @retval EFI_OUT_OF_RESOURCES     Failed due to lack of memory resources.
  @retval Others                   Other errors as indicated.

**/
EFI_STATUS
MnpGroupOp (
  IN OUT MNP_INSTANCE_DATA         *Instance,
  IN     BOOLEAN                   JoinFlag,
  IN     EFI_MAC_ADDRESS           *MacAddress OPTIONAL,
  IN     MNP_GROUP_CONTROL_BLOCK   *CtrlBlk OPTIONAL
  )
{
  MNP_DEVICE_DATA         *MnpDeviceData;
  LIST_ENTRY              *Entry;
  LIST_ENTRY              *NextEntry;
  MNP_GROUP_ADDRESS       *GroupAddress;
  EFI_SIMPLE_NETWORK_MODE *SnpMode;
  MNP_GROUP_CONTROL_BLOCK *NewCtrlBlk;
  EFI_STATUS              Status;
  BOOLEAN                 AddressExist;
  BOOLEAN                 NeedUpdate;

  NET_CHECK_SIGNATURE (Instance, MNP_INSTANCE_DATA_SIGNATURE);

  MnpDeviceData = Instance->MnpServiceData->MnpDeviceData;
  SnpMode       = MnpDeviceData->Snp->Mode;

  if (JoinFlag) {
    //
    // A new group address is to be added.
    //
    GroupAddress  = NULL;
    AddressExist  = FALSE;

    //
    // Allocate memory for the control block.
    //
    NewCtrlBlk = AllocatePool (sizeof (MNP_GROUP_CONTROL_BLOCK));
    if (NewCtrlBlk == NULL) {
      DEBUG ((EFI_D_ERROR, "MnpGroupOp: Failed to allocate memory resource.\n"));

      return EFI_OUT_OF_RESOURCES;
    }

    NET_LIST_FOR_EACH (Entry, &MnpDeviceData->GroupAddressList) {
      //
      // Check whether the MacAddress is already joined by other instances.
      //
      GroupAddress = NET_LIST_USER_STRUCT (Entry, MNP_GROUP_ADDRESS, AddrEntry);
      if (CompareMem (MacAddress, &GroupAddress->Address, SnpMode->HwAddressSize) == 0) {
        AddressExist = TRUE;
        break;
      }
    }

    if (!AddressExist) {
      GroupAddress = NULL;
    }

    //
    // Add the GroupAddress for this instance.
    //
    Status = MnpGroupOpAddCtrlBlk (
              Instance,
              NewCtrlBlk,
              GroupAddress,
              MacAddress,
              SnpMode->HwAddressSize
              );
    if (EFI_ERROR (Status)) {
      return Status;
    }

    NeedUpdate = TRUE;
  } else {
    if (MacAddress != NULL) {
      ASSERT (CtrlBlk != NULL);

      //
      // Leave the specific multicast mac address.
      //
      NeedUpdate = MnpGroupOpDelCtrlBlk (Instance, CtrlBlk);
    } else {
      //
      // Leave all multicast mac addresses.
      //
      NeedUpdate = FALSE;

      NET_LIST_FOR_EACH_SAFE (Entry, NextEntry, &Instance->GroupCtrlBlkList) {

        NewCtrlBlk = NET_LIST_USER_STRUCT (
                      Entry,
                      MNP_GROUP_CONTROL_BLOCK,
                      CtrlBlkEntry
                      );
        //
        // Update is required if the group address left is no longer used
        // by other instances.
        //
        NeedUpdate = MnpGroupOpDelCtrlBlk (Instance, NewCtrlBlk);
      }
    }
  }

  Status = EFI_SUCCESS;

  if (NeedUpdate) {
    //
    // Reconfigure the receive filters if necessary.
    //
    Status = MnpConfigReceiveFilters (MnpDeviceData);
  }

  return Status;
}