summaryrefslogtreecommitdiffstats
path: root/drivers/target/target_core_transport.c
blob: 2cfd61d62e9730503414817d52c053c4083ba9e7 (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
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
/*******************************************************************************
 * Filename:  target_core_transport.c
 *
 * This file contains the Generic Target Engine Core.
 *
 * (c) Copyright 2002-2013 Datera, Inc.
 *
 * Nicholas A. Bellinger <nab@kernel.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 ******************************************************************************/

#include <linux/net.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
#include <linux/in.h>
#include <linux/cdrom.h>
#include <linux/module.h>
#include <linux/ratelimit.h>
#include <linux/vmalloc.h>
#include <asm/unaligned.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <scsi/scsi_proto.h>
#include <scsi/scsi_common.h>

#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>

#include "target_core_internal.h"
#include "target_core_alua.h"
#include "target_core_pr.h"
#include "target_core_ua.h"

#define CREATE_TRACE_POINTS
#include <trace/events/target.h>

static struct workqueue_struct *target_completion_wq;
static struct kmem_cache *se_sess_cache;
struct kmem_cache *se_ua_cache;
struct kmem_cache *t10_pr_reg_cache;
struct kmem_cache *t10_alua_lu_gp_cache;
struct kmem_cache *t10_alua_lu_gp_mem_cache;
struct kmem_cache *t10_alua_tg_pt_gp_cache;
struct kmem_cache *t10_alua_lba_map_cache;
struct kmem_cache *t10_alua_lba_map_mem_cache;

static void transport_complete_task_attr(struct se_cmd *cmd);
static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
static void transport_handle_queue_full(struct se_cmd *cmd,
		struct se_device *dev, int err, bool write_pending);
static void target_complete_ok_work(struct work_struct *work);

int init_se_kmem_caches(void)
{
	se_sess_cache = kmem_cache_create("se_sess_cache",
			sizeof(struct se_session), __alignof__(struct se_session),
			0, NULL);
	if (!se_sess_cache) {
		pr_err("kmem_cache_create() for struct se_session"
				" failed\n");
		goto out;
	}
	se_ua_cache = kmem_cache_create("se_ua_cache",
			sizeof(struct se_ua), __alignof__(struct se_ua),
			0, NULL);
	if (!se_ua_cache) {
		pr_err("kmem_cache_create() for struct se_ua failed\n");
		goto out_free_sess_cache;
	}
	t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
			sizeof(struct t10_pr_registration),
			__alignof__(struct t10_pr_registration), 0, NULL);
	if (!t10_pr_reg_cache) {
		pr_err("kmem_cache_create() for struct t10_pr_registration"
				" failed\n");
		goto out_free_ua_cache;
	}
	t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
			sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
			0, NULL);
	if (!t10_alua_lu_gp_cache) {
		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
				" failed\n");
		goto out_free_pr_reg_cache;
	}
	t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
			sizeof(struct t10_alua_lu_gp_member),
			__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
	if (!t10_alua_lu_gp_mem_cache) {
		pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
				"cache failed\n");
		goto out_free_lu_gp_cache;
	}
	t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
			sizeof(struct t10_alua_tg_pt_gp),
			__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
	if (!t10_alua_tg_pt_gp_cache) {
		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
				"cache failed\n");
		goto out_free_lu_gp_mem_cache;
	}
	t10_alua_lba_map_cache = kmem_cache_create(
			"t10_alua_lba_map_cache",
			sizeof(struct t10_alua_lba_map),
			__alignof__(struct t10_alua_lba_map), 0, NULL);
	if (!t10_alua_lba_map_cache) {
		pr_err("kmem_cache_create() for t10_alua_lba_map_"
				"cache failed\n");
		goto out_free_tg_pt_gp_cache;
	}
	t10_alua_lba_map_mem_cache = kmem_cache_create(
			"t10_alua_lba_map_mem_cache",
			sizeof(struct t10_alua_lba_map_member),
			__alignof__(struct t10_alua_lba_map_member), 0, NULL);
	if (!t10_alua_lba_map_mem_cache) {
		pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
				"cache failed\n");
		goto out_free_lba_map_cache;
	}

	target_completion_wq = alloc_workqueue("target_completion",
					       WQ_MEM_RECLAIM, 0);
	if (!target_completion_wq)
		goto out_free_lba_map_mem_cache;

	return 0;

out_free_lba_map_mem_cache:
	kmem_cache_destroy(t10_alua_lba_map_mem_cache);
out_free_lba_map_cache:
	kmem_cache_destroy(t10_alua_lba_map_cache);
out_free_tg_pt_gp_cache:
	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
out_free_lu_gp_mem_cache:
	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
out_free_lu_gp_cache:
	kmem_cache_destroy(t10_alua_lu_gp_cache);
out_free_pr_reg_cache:
	kmem_cache_destroy(t10_pr_reg_cache);
out_free_ua_cache:
	kmem_cache_destroy(se_ua_cache);
out_free_sess_cache:
	kmem_cache_destroy(se_sess_cache);
out:
	return -ENOMEM;
}

void release_se_kmem_caches(void)
{
	destroy_workqueue(target_completion_wq);
	kmem_cache_destroy(se_sess_cache);
	kmem_cache_destroy(se_ua_cache);
	kmem_cache_destroy(t10_pr_reg_cache);
	kmem_cache_destroy(t10_alua_lu_gp_cache);
	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
	kmem_cache_destroy(t10_alua_lba_map_cache);
	kmem_cache_destroy(t10_alua_lba_map_mem_cache);
}

/* This code ensures unique mib indexes are handed out. */
static DEFINE_SPINLOCK(scsi_mib_index_lock);
static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];

/*
 * Allocate a new row index for the entry type specified
 */
u32 scsi_get_new_index(scsi_index_t type)
{
	u32 new_index;

	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));

	spin_lock(&scsi_mib_index_lock);
	new_index = ++scsi_mib_index[type];
	spin_unlock(&scsi_mib_index_lock);

	return new_index;
}

void transport_subsystem_check_init(void)
{
	int ret;
	static int sub_api_initialized;

	if (sub_api_initialized)
		return;

	ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
	if (ret != 0)
		pr_err("Unable to load target_core_iblock\n");

	ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
	if (ret != 0)
		pr_err("Unable to load target_core_file\n");

	ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
	if (ret != 0)
		pr_err("Unable to load target_core_pscsi\n");

	ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
	if (ret != 0)
		pr_err("Unable to load target_core_user\n");

	sub_api_initialized = 1;
}

/**
 * transport_init_session - initialize a session object
 * @se_sess: Session object pointer.
 *
 * The caller must have zero-initialized @se_sess before calling this function.
 */
void transport_init_session(struct se_session *se_sess)
{
	INIT_LIST_HEAD(&se_sess->sess_list);
	INIT_LIST_HEAD(&se_sess->sess_acl_list);
	INIT_LIST_HEAD(&se_sess->sess_cmd_list);
	spin_lock_init(&se_sess->sess_cmd_lock);
	init_waitqueue_head(&se_sess->cmd_list_wq);
}
EXPORT_SYMBOL(transport_init_session);

/**
 * transport_alloc_session - allocate a session object and initialize it
 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 */
struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
{
	struct se_session *se_sess;

	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
	if (!se_sess) {
		pr_err("Unable to allocate struct se_session from"
				" se_sess_cache\n");
		return ERR_PTR(-ENOMEM);
	}
	transport_init_session(se_sess);
	se_sess->sup_prot_ops = sup_prot_ops;

	return se_sess;
}
EXPORT_SYMBOL(transport_alloc_session);

/**
 * transport_alloc_session_tags - allocate target driver private data
 * @se_sess:  Session pointer.
 * @tag_num:  Maximum number of in-flight commands between initiator and target.
 * @tag_size: Size in bytes of the private data a target driver associates with
 *	      each command.
 */
int transport_alloc_session_tags(struct se_session *se_sess,
			         unsigned int tag_num, unsigned int tag_size)
{
	int rc;

	se_sess->sess_cmd_map = kcalloc(tag_size, tag_num,
					GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
	if (!se_sess->sess_cmd_map) {
		se_sess->sess_cmd_map = vzalloc(array_size(tag_size, tag_num));
		if (!se_sess->sess_cmd_map) {
			pr_err("Unable to allocate se_sess->sess_cmd_map\n");
			return -ENOMEM;
		}
	}

	rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
			false, GFP_KERNEL, NUMA_NO_NODE);
	if (rc < 0) {
		pr_err("Unable to init se_sess->sess_tag_pool,"
			" tag_num: %u\n", tag_num);
		kvfree(se_sess->sess_cmd_map);
		se_sess->sess_cmd_map = NULL;
		return -ENOMEM;
	}

	return 0;
}
EXPORT_SYMBOL(transport_alloc_session_tags);

/**
 * transport_init_session_tags - allocate a session and target driver private data
 * @tag_num:  Maximum number of in-flight commands between initiator and target.
 * @tag_size: Size in bytes of the private data a target driver associates with
 *	      each command.
 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 */
static struct se_session *
transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
			    enum target_prot_op sup_prot_ops)
{
	struct se_session *se_sess;
	int rc;

	if (tag_num != 0 && !tag_size) {
		pr_err("init_session_tags called with percpu-ida tag_num:"
		       " %u, but zero tag_size\n", tag_num);
		return ERR_PTR(-EINVAL);
	}
	if (!tag_num && tag_size) {
		pr_err("init_session_tags called with percpu-ida tag_size:"
		       " %u, but zero tag_num\n", tag_size);
		return ERR_PTR(-EINVAL);
	}

	se_sess = transport_alloc_session(sup_prot_ops);
	if (IS_ERR(se_sess))
		return se_sess;

	rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
	if (rc < 0) {
		transport_free_session(se_sess);
		return ERR_PTR(-ENOMEM);
	}

	return se_sess;
}

/*
 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 */
void __transport_register_session(
	struct se_portal_group *se_tpg,
	struct se_node_acl *se_nacl,
	struct se_session *se_sess,
	void *fabric_sess_ptr)
{
	const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
	unsigned char buf[PR_REG_ISID_LEN];
	unsigned long flags;

	se_sess->se_tpg = se_tpg;
	se_sess->fabric_sess_ptr = fabric_sess_ptr;
	/*
	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
	 *
	 * Only set for struct se_session's that will actually be moving I/O.
	 * eg: *NOT* discovery sessions.
	 */
	if (se_nacl) {
		/*
		 *
		 * Determine if fabric allows for T10-PI feature bits exposed to
		 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
		 *
		 * If so, then always save prot_type on a per se_node_acl node
		 * basis and re-instate the previous sess_prot_type to avoid
		 * disabling PI from below any previously initiator side
		 * registered LUNs.
		 */
		if (se_nacl->saved_prot_type)
			se_sess->sess_prot_type = se_nacl->saved_prot_type;
		else if (tfo->tpg_check_prot_fabric_only)
			se_sess->sess_prot_type = se_nacl->saved_prot_type =
					tfo->tpg_check_prot_fabric_only(se_tpg);
		/*
		 * If the fabric module supports an ISID based TransportID,
		 * save this value in binary from the fabric I_T Nexus now.
		 */
		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
			memset(&buf[0], 0, PR_REG_ISID_LEN);
			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
					&buf[0], PR_REG_ISID_LEN);
			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
		}

		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
		/*
		 * The se_nacl->nacl_sess pointer will be set to the
		 * last active I_T Nexus for each struct se_node_acl.
		 */
		se_nacl->nacl_sess = se_sess;

		list_add_tail(&se_sess->sess_acl_list,
			      &se_nacl->acl_sess_list);
		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
	}
	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);

	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
		se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
}
EXPORT_SYMBOL(__transport_register_session);

void transport_register_session(
	struct se_portal_group *se_tpg,
	struct se_node_acl *se_nacl,
	struct se_session *se_sess,
	void *fabric_sess_ptr)
{
	unsigned long flags;

	spin_lock_irqsave(&se_tpg->session_lock, flags);
	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
}
EXPORT_SYMBOL(transport_register_session);

struct se_session *
target_setup_session(struct se_portal_group *tpg,
		     unsigned int tag_num, unsigned int tag_size,
		     enum target_prot_op prot_op,
		     const char *initiatorname, void *private,
		     int (*callback)(struct se_portal_group *,
				     struct se_session *, void *))
{
	struct se_session *sess;

	/*
	 * If the fabric driver is using percpu-ida based pre allocation
	 * of I/O descriptor tags, go ahead and perform that setup now..
	 */
	if (tag_num != 0)
		sess = transport_init_session_tags(tag_num, tag_size, prot_op);
	else
		sess = transport_alloc_session(prot_op);

	if (IS_ERR(sess))
		return sess;

	sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
					(unsigned char *)initiatorname);
	if (!sess->se_node_acl) {
		transport_free_session(sess);
		return ERR_PTR(-EACCES);
	}
	/*
	 * Go ahead and perform any remaining fabric setup that is
	 * required before transport_register_session().
	 */
	if (callback != NULL) {
		int rc = callback(tpg, sess, private);
		if (rc) {
			transport_free_session(sess);
			return ERR_PTR(rc);
		}
	}

	transport_register_session(tpg, sess->se_node_acl, sess, private);
	return sess;
}
EXPORT_SYMBOL(target_setup_session);

ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
{
	struct se_session *se_sess;
	ssize_t len = 0;

	spin_lock_bh(&se_tpg->session_lock);
	list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
		if (!se_sess->se_node_acl)
			continue;
		if (!se_sess->se_node_acl->dynamic_node_acl)
			continue;
		if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
			break;

		len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
				se_sess->se_node_acl->initiatorname);
		len += 1; /* Include NULL terminator */
	}
	spin_unlock_bh(&se_tpg->session_lock);

	return len;
}
EXPORT_SYMBOL(target_show_dynamic_sessions);

static void target_complete_nacl(struct kref *kref)
{
	struct se_node_acl *nacl = container_of(kref,
				struct se_node_acl, acl_kref);
	struct se_portal_group *se_tpg = nacl->se_tpg;

	if (!nacl->dynamic_stop) {
		complete(&nacl->acl_free_comp);
		return;
	}

	mutex_lock(&se_tpg->acl_node_mutex);
	list_del_init(&nacl->acl_list);
	mutex_unlock(&se_tpg->acl_node_mutex);

	core_tpg_wait_for_nacl_pr_ref(nacl);
	core_free_device_list_for_node(nacl, se_tpg);
	kfree(nacl);
}

void target_put_nacl(struct se_node_acl *nacl)
{
	kref_put(&nacl->acl_kref, target_complete_nacl);
}
EXPORT_SYMBOL(target_put_nacl);

void transport_deregister_session_configfs(struct se_session *se_sess)
{
	struct se_node_acl *se_nacl;
	unsigned long flags;
	/*
	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
	 */
	se_nacl = se_sess->se_node_acl;
	if (se_nacl) {
		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
		if (!list_empty(&se_sess->sess_acl_list))
			list_del_init(&se_sess->sess_acl_list);
		/*
		 * If the session list is empty, then clear the pointer.
		 * Otherwise, set the struct se_session pointer from the tail
		 * element of the per struct se_node_acl active session list.
		 */
		if (list_empty(&se_nacl->acl_sess_list))
			se_nacl->nacl_sess = NULL;
		else {
			se_nacl->nacl_sess = container_of(
					se_nacl->acl_sess_list.prev,
					struct se_session, sess_acl_list);
		}
		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
	}
}
EXPORT_SYMBOL(transport_deregister_session_configfs);

void transport_free_session(struct se_session *se_sess)
{
	struct se_node_acl *se_nacl = se_sess->se_node_acl;

	/*
	 * Drop the se_node_acl->nacl_kref obtained from within
	 * core_tpg_get_initiator_node_acl().
	 */
	if (se_nacl) {
		struct se_portal_group *se_tpg = se_nacl->se_tpg;
		const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
		unsigned long flags;

		se_sess->se_node_acl = NULL;

		/*
		 * Also determine if we need to drop the extra ->cmd_kref if
		 * it had been previously dynamically generated, and
		 * the endpoint is not caching dynamic ACLs.
		 */
		mutex_lock(&se_tpg->acl_node_mutex);
		if (se_nacl->dynamic_node_acl &&
		    !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
			spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
			if (list_empty(&se_nacl->acl_sess_list))
				se_nacl->dynamic_stop = true;
			spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);

			if (se_nacl->dynamic_stop)
				list_del_init(&se_nacl->acl_list);
		}
		mutex_unlock(&se_tpg->acl_node_mutex);

		if (se_nacl->dynamic_stop)
			target_put_nacl(se_nacl);

		target_put_nacl(se_nacl);
	}
	if (se_sess->sess_cmd_map) {
		sbitmap_queue_free(&se_sess->sess_tag_pool);
		kvfree(se_sess->sess_cmd_map);
	}
	kmem_cache_free(se_sess_cache, se_sess);
}
EXPORT_SYMBOL(transport_free_session);

void transport_deregister_session(struct se_session *se_sess)
{
	struct se_portal_group *se_tpg = se_sess->se_tpg;
	unsigned long flags;

	if (!se_tpg) {
		transport_free_session(se_sess);
		return;
	}

	spin_lock_irqsave(&se_tpg->session_lock, flags);
	list_del(&se_sess->sess_list);
	se_sess->se_tpg = NULL;
	se_sess->fabric_sess_ptr = NULL;
	spin_unlock_irqrestore(&se_tpg->session_lock, flags);

	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
		se_tpg->se_tpg_tfo->get_fabric_name());
	/*
	 * If last kref is dropping now for an explicit NodeACL, awake sleeping
	 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
	 * removal context from within transport_free_session() code.
	 *
	 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
	 * to release all remaining generate_node_acl=1 created ACL resources.
	 */

	transport_free_session(se_sess);
}
EXPORT_SYMBOL(transport_deregister_session);

void target_remove_session(struct se_session *se_sess)
{
	transport_deregister_session_configfs(se_sess);
	transport_deregister_session(se_sess);
}
EXPORT_SYMBOL(target_remove_session);

static void target_remove_from_state_list(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;
	unsigned long flags;

	if (!dev)
		return;

	spin_lock_irqsave(&dev->execute_task_lock, flags);
	if (cmd->state_active) {
		list_del(&cmd->state_list);
		cmd->state_active = false;
	}
	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}

/*
 * This function is called by the target core after the target core has
 * finished processing a SCSI command or SCSI TMF. Both the regular command
 * processing code and the code for aborting commands can call this
 * function. CMD_T_STOP is set if and only if another thread is waiting
 * inside transport_wait_for_tasks() for t_transport_stop_comp.
 */
static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
{
	unsigned long flags;

	target_remove_from_state_list(cmd);

	/*
	 * Clear struct se_cmd->se_lun before the handoff to FE.
	 */
	cmd->se_lun = NULL;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	/*
	 * Determine if frontend context caller is requesting the stopping of
	 * this command for frontend exceptions.
	 */
	if (cmd->transport_state & CMD_T_STOP) {
		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
			__func__, __LINE__, cmd->tag);

		spin_unlock_irqrestore(&cmd->t_state_lock, flags);

		complete_all(&cmd->t_transport_stop_comp);
		return 1;
	}
	cmd->transport_state &= ~CMD_T_ACTIVE;
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	/*
	 * Some fabric modules like tcm_loop can release their internally
	 * allocated I/O reference and struct se_cmd now.
	 *
	 * Fabric modules are expected to return '1' here if the se_cmd being
	 * passed is released at this point, or zero if not being released.
	 */
	return cmd->se_tfo->check_stop_free(cmd);
}

static void transport_lun_remove_cmd(struct se_cmd *cmd)
{
	struct se_lun *lun = cmd->se_lun;

	if (!lun)
		return;

	if (cmpxchg(&cmd->lun_ref_active, true, false))
		percpu_ref_put(&lun->lun_ref);
}

int transport_cmd_finish_abort(struct se_cmd *cmd)
{
	bool send_tas = cmd->transport_state & CMD_T_TAS;
	bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
	int ret = 0;

	if (send_tas)
		transport_send_task_abort(cmd);

	if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
		transport_lun_remove_cmd(cmd);
	/*
	 * Allow the fabric driver to unmap any resources before
	 * releasing the descriptor via TFO->release_cmd()
	 */
	if (!send_tas)
		cmd->se_tfo->aborted_task(cmd);

	if (transport_cmd_check_stop_to_fabric(cmd))
		return 1;
	if (!send_tas && ack_kref)
		ret = target_put_sess_cmd(cmd);

	return ret;
}

static void target_complete_failure_work(struct work_struct *work)
{
	struct se_cmd *cmd = container_of(work, struct se_cmd, work);

	transport_generic_request_failure(cmd,
			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
}

/*
 * Used when asking transport to copy Sense Data from the underlying
 * Linux/SCSI struct scsi_cmnd
 */
static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;

	WARN_ON(!cmd->se_lun);

	if (!dev)
		return NULL;

	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
		return NULL;

	cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;

	pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
		dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
	return cmd->sense_buffer;
}

void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
{
	unsigned char *cmd_sense_buf;
	unsigned long flags;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	cmd_sense_buf = transport_get_sense_buffer(cmd);
	if (!cmd_sense_buf) {
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		return;
	}

	cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
	memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
EXPORT_SYMBOL(transport_copy_sense_to_cmd);

void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
{
	struct se_device *dev = cmd->se_dev;
	int success;
	unsigned long flags;

	cmd->scsi_status = scsi_status;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	switch (cmd->scsi_status) {
	case SAM_STAT_CHECK_CONDITION:
		if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
			success = 1;
		else
			success = 0;
		break;
	default:
		success = 1;
		break;
	}

	/*
	 * Check for case where an explicit ABORT_TASK has been received
	 * and transport_wait_for_tasks() will be waiting for completion..
	 */
	if (cmd->transport_state & CMD_T_ABORTED ||
	    cmd->transport_state & CMD_T_STOP) {
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		/*
		 * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(),
		 * release se_device->caw_sem obtained by sbc_compare_and_write()
		 * since target_complete_ok_work() or target_complete_failure_work()
		 * won't be called to invoke the normal CAW completion callbacks.
		 */
		if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
			up(&dev->caw_sem);
		}
		complete_all(&cmd->t_transport_stop_comp);
		return;
	} else if (!success) {
		INIT_WORK(&cmd->work, target_complete_failure_work);
	} else {
		INIT_WORK(&cmd->work, target_complete_ok_work);
	}

	cmd->t_state = TRANSPORT_COMPLETE;
	cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	if (cmd->se_cmd_flags & SCF_USE_CPUID)
		queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
	else
		queue_work(target_completion_wq, &cmd->work);
}
EXPORT_SYMBOL(target_complete_cmd);

void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
{
	if ((scsi_status == SAM_STAT_GOOD ||
	     cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
	    length < cmd->data_length) {
		if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
			cmd->residual_count += cmd->data_length - length;
		} else {
			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
			cmd->residual_count = cmd->data_length - length;
		}

		cmd->data_length = length;
	}

	target_complete_cmd(cmd, scsi_status);
}
EXPORT_SYMBOL(target_complete_cmd_with_length);

static void target_add_to_state_list(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;
	unsigned long flags;

	spin_lock_irqsave(&dev->execute_task_lock, flags);
	if (!cmd->state_active) {
		list_add_tail(&cmd->state_list, &dev->state_list);
		cmd->state_active = true;
	}
	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}

/*
 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 */
static void transport_write_pending_qf(struct se_cmd *cmd);
static void transport_complete_qf(struct se_cmd *cmd);

void target_qf_do_work(struct work_struct *work)
{
	struct se_device *dev = container_of(work, struct se_device,
					qf_work_queue);
	LIST_HEAD(qf_cmd_list);
	struct se_cmd *cmd, *cmd_tmp;

	spin_lock_irq(&dev->qf_cmd_lock);
	list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
	spin_unlock_irq(&dev->qf_cmd_lock);

	list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
		list_del(&cmd->se_qf_node);
		atomic_dec_mb(&dev->dev_qf_count);

		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
			" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
			(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
			: "UNKNOWN");

		if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
			transport_write_pending_qf(cmd);
		else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
			 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
			transport_complete_qf(cmd);
	}
}

unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
{
	switch (cmd->data_direction) {
	case DMA_NONE:
		return "NONE";
	case DMA_FROM_DEVICE:
		return "READ";
	case DMA_TO_DEVICE:
		return "WRITE";
	case DMA_BIDIRECTIONAL:
		return "BIDI";
	default:
		break;
	}

	return "UNKNOWN";
}

void transport_dump_dev_state(
	struct se_device *dev,
	char *b,
	int *bl)
{
	*bl += sprintf(b + *bl, "Status: ");
	if (dev->export_count)
		*bl += sprintf(b + *bl, "ACTIVATED");
	else
		*bl += sprintf(b + *bl, "DEACTIVATED");

	*bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
	*bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
		dev->dev_attrib.block_size,
		dev->dev_attrib.hw_max_sectors);
	*bl += sprintf(b + *bl, "        ");
}

void transport_dump_vpd_proto_id(
	struct t10_vpd *vpd,
	unsigned char *p_buf,
	int p_buf_len)
{
	unsigned char buf[VPD_TMP_BUF_SIZE];
	int len;

	memset(buf, 0, VPD_TMP_BUF_SIZE);
	len = sprintf(buf, "T10 VPD Protocol Identifier: ");

	switch (vpd->protocol_identifier) {
	case 0x00:
		sprintf(buf+len, "Fibre Channel\n");
		break;
	case 0x10:
		sprintf(buf+len, "Parallel SCSI\n");
		break;
	case 0x20:
		sprintf(buf+len, "SSA\n");
		break;
	case 0x30:
		sprintf(buf+len, "IEEE 1394\n");
		break;
	case 0x40:
		sprintf(buf+len, "SCSI Remote Direct Memory Access"
				" Protocol\n");
		break;
	case 0x50:
		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
		break;
	case 0x60:
		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
		break;
	case 0x70:
		sprintf(buf+len, "Automation/Drive Interface Transport"
				" Protocol\n");
		break;
	case 0x80:
		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
		break;
	default:
		sprintf(buf+len, "Unknown 0x%02x\n",
				vpd->protocol_identifier);
		break;
	}

	if (p_buf)
		strncpy(p_buf, buf, p_buf_len);
	else
		pr_debug("%s", buf);
}

void
transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
{
	/*
	 * Check if the Protocol Identifier Valid (PIV) bit is set..
	 *
	 * from spc3r23.pdf section 7.5.1
	 */
	 if (page_83[1] & 0x80) {
		vpd->protocol_identifier = (page_83[0] & 0xf0);
		vpd->protocol_identifier_set = 1;
		transport_dump_vpd_proto_id(vpd, NULL, 0);
	}
}
EXPORT_SYMBOL(transport_set_vpd_proto_id);

int transport_dump_vpd_assoc(
	struct t10_vpd *vpd,
	unsigned char *p_buf,
	int p_buf_len)
{
	unsigned char buf[VPD_TMP_BUF_SIZE];
	int ret = 0;
	int len;

	memset(buf, 0, VPD_TMP_BUF_SIZE);
	len = sprintf(buf, "T10 VPD Identifier Association: ");

	switch (vpd->association) {
	case 0x00:
		sprintf(buf+len, "addressed logical unit\n");
		break;
	case 0x10:
		sprintf(buf+len, "target port\n");
		break;
	case 0x20:
		sprintf(buf+len, "SCSI target device\n");
		break;
	default:
		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
		ret = -EINVAL;
		break;
	}

	if (p_buf)
		strncpy(p_buf, buf, p_buf_len);
	else
		pr_debug("%s", buf);

	return ret;
}

int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
{
	/*
	 * The VPD identification association..
	 *
	 * from spc3r23.pdf Section 7.6.3.1 Table 297
	 */
	vpd->association = (page_83[1] & 0x30);
	return transport_dump_vpd_assoc(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_assoc);

int transport_dump_vpd_ident_type(
	struct t10_vpd *vpd,
	unsigned char *p_buf,
	int p_buf_len)
{
	unsigned char buf[VPD_TMP_BUF_SIZE];
	int ret = 0;
	int len;

	memset(buf, 0, VPD_TMP_BUF_SIZE);
	len = sprintf(buf, "T10 VPD Identifier Type: ");

	switch (vpd->device_identifier_type) {
	case 0x00:
		sprintf(buf+len, "Vendor specific\n");
		break;
	case 0x01:
		sprintf(buf+len, "T10 Vendor ID based\n");
		break;
	case 0x02:
		sprintf(buf+len, "EUI-64 based\n");
		break;
	case 0x03:
		sprintf(buf+len, "NAA\n");
		break;
	case 0x04:
		sprintf(buf+len, "Relative target port identifier\n");
		break;
	case 0x08:
		sprintf(buf+len, "SCSI name string\n");
		break;
	default:
		sprintf(buf+len, "Unsupported: 0x%02x\n",
				vpd->device_identifier_type);
		ret = -EINVAL;
		break;
	}

	if (p_buf) {
		if (p_buf_len < strlen(buf)+1)
			return -EINVAL;
		strncpy(p_buf, buf, p_buf_len);
	} else {
		pr_debug("%s", buf);
	}

	return ret;
}

int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
{
	/*
	 * The VPD identifier type..
	 *
	 * from spc3r23.pdf Section 7.6.3.1 Table 298
	 */
	vpd->device_identifier_type = (page_83[1] & 0x0f);
	return transport_dump_vpd_ident_type(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_ident_type);

int transport_dump_vpd_ident(
	struct t10_vpd *vpd,
	unsigned char *p_buf,
	int p_buf_len)
{
	unsigned char buf[VPD_TMP_BUF_SIZE];
	int ret = 0;

	memset(buf, 0, VPD_TMP_BUF_SIZE);

	switch (vpd->device_identifier_code_set) {
	case 0x01: /* Binary */
		snprintf(buf, sizeof(buf),
			"T10 VPD Binary Device Identifier: %s\n",
			&vpd->device_identifier[0]);
		break;
	case 0x02: /* ASCII */
		snprintf(buf, sizeof(buf),
			"T10 VPD ASCII Device Identifier: %s\n",
			&vpd->device_identifier[0]);
		break;
	case 0x03: /* UTF-8 */
		snprintf(buf, sizeof(buf),
			"T10 VPD UTF-8 Device Identifier: %s\n",
			&vpd->device_identifier[0]);
		break;
	default:
		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
			" 0x%02x", vpd->device_identifier_code_set);
		ret = -EINVAL;
		break;
	}

	if (p_buf)
		strncpy(p_buf, buf, p_buf_len);
	else
		pr_debug("%s", buf);

	return ret;
}

int
transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
{
	static const char hex_str[] = "0123456789abcdef";
	int j = 0, i = 4; /* offset to start of the identifier */

	/*
	 * The VPD Code Set (encoding)
	 *
	 * from spc3r23.pdf Section 7.6.3.1 Table 296
	 */
	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
	switch (vpd->device_identifier_code_set) {
	case 0x01: /* Binary */
		vpd->device_identifier[j++] =
				hex_str[vpd->device_identifier_type];
		while (i < (4 + page_83[3])) {
			vpd->device_identifier[j++] =
				hex_str[(page_83[i] & 0xf0) >> 4];
			vpd->device_identifier[j++] =
				hex_str[page_83[i] & 0x0f];
			i++;
		}
		break;
	case 0x02: /* ASCII */
	case 0x03: /* UTF-8 */
		while (i < (4 + page_83[3]))
			vpd->device_identifier[j++] = page_83[i++];
		break;
	default:
		break;
	}

	return transport_dump_vpd_ident(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_ident);

static sense_reason_t
target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
			       unsigned int size)
{
	u32 mtl;

	if (!cmd->se_tfo->max_data_sg_nents)
		return TCM_NO_SENSE;
	/*
	 * Check if fabric enforced maximum SGL entries per I/O descriptor
	 * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
	 * residual_count and reduce original cmd->data_length to maximum
	 * length based on single PAGE_SIZE entry scatter-lists.
	 */
	mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
	if (cmd->data_length > mtl) {
		/*
		 * If an existing CDB overflow is present, calculate new residual
		 * based on CDB size minus fabric maximum transfer length.
		 *
		 * If an existing CDB underflow is present, calculate new residual
		 * based on original cmd->data_length minus fabric maximum transfer
		 * length.
		 *
		 * Otherwise, set the underflow residual based on cmd->data_length
		 * minus fabric maximum transfer length.
		 */
		if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
			cmd->residual_count = (size - mtl);
		} else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
			u32 orig_dl = size + cmd->residual_count;
			cmd->residual_count = (orig_dl - mtl);
		} else {
			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
			cmd->residual_count = (cmd->data_length - mtl);
		}
		cmd->data_length = mtl;
		/*
		 * Reset sbc_check_prot() calculated protection payload
		 * length based upon the new smaller MTL.
		 */
		if (cmd->prot_length) {
			u32 sectors = (mtl / dev->dev_attrib.block_size);
			cmd->prot_length = dev->prot_length * sectors;
		}
	}
	return TCM_NO_SENSE;
}

sense_reason_t
target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
{
	struct se_device *dev = cmd->se_dev;

	if (cmd->unknown_data_length) {
		cmd->data_length = size;
	} else if (size != cmd->data_length) {
		pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
				cmd->data_length, size, cmd->t_task_cdb[0]);

		if (cmd->data_direction == DMA_TO_DEVICE) {
			if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
				pr_err_ratelimited("Rejecting underflow/overflow"
						   " for WRITE data CDB\n");
				return TCM_INVALID_CDB_FIELD;
			}
			/*
			 * Some fabric drivers like iscsi-target still expect to
			 * always reject overflow writes.  Reject this case until
			 * full fabric driver level support for overflow writes
			 * is introduced tree-wide.
			 */
			if (size > cmd->data_length) {
				pr_err_ratelimited("Rejecting overflow for"
						   " WRITE control CDB\n");
				return TCM_INVALID_CDB_FIELD;
			}
		}
		/*
		 * Reject READ_* or WRITE_* with overflow/underflow for
		 * type SCF_SCSI_DATA_CDB.
		 */
		if (dev->dev_attrib.block_size != 512)  {
			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
				" CDB on non 512-byte sector setup subsystem"
				" plugin: %s\n", dev->transport->name);
			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
			return TCM_INVALID_CDB_FIELD;
		}
		/*
		 * For the overflow case keep the existing fabric provided
		 * ->data_length.  Otherwise for the underflow case, reset
		 * ->data_length to the smaller SCSI expected data transfer
		 * length.
		 */
		if (size > cmd->data_length) {
			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
			cmd->residual_count = (size - cmd->data_length);
		} else {
			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
			cmd->residual_count = (cmd->data_length - size);
			cmd->data_length = size;
		}
	}

	return target_check_max_data_sg_nents(cmd, dev, size);

}

/*
 * Used by fabric modules containing a local struct se_cmd within their
 * fabric dependent per I/O descriptor.
 *
 * Preserves the value of @cmd->tag.
 */
void transport_init_se_cmd(
	struct se_cmd *cmd,
	const struct target_core_fabric_ops *tfo,
	struct se_session *se_sess,
	u32 data_length,
	int data_direction,
	int task_attr,
	unsigned char *sense_buffer)
{
	INIT_LIST_HEAD(&cmd->se_delayed_node);
	INIT_LIST_HEAD(&cmd->se_qf_node);
	INIT_LIST_HEAD(&cmd->se_cmd_list);
	INIT_LIST_HEAD(&cmd->state_list);
	init_completion(&cmd->t_transport_stop_comp);
	cmd->compl = NULL;
	spin_lock_init(&cmd->t_state_lock);
	INIT_WORK(&cmd->work, NULL);
	kref_init(&cmd->cmd_kref);

	cmd->se_tfo = tfo;
	cmd->se_sess = se_sess;
	cmd->data_length = data_length;
	cmd->data_direction = data_direction;
	cmd->sam_task_attr = task_attr;
	cmd->sense_buffer = sense_buffer;

	cmd->state_active = false;
}
EXPORT_SYMBOL(transport_init_se_cmd);

static sense_reason_t
transport_check_alloc_task_attr(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;

	/*
	 * Check if SAM Task Attribute emulation is enabled for this
	 * struct se_device storage object
	 */
	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
		return 0;

	if (cmd->sam_task_attr == TCM_ACA_TAG) {
		pr_debug("SAM Task Attribute ACA"
			" emulation is not supported\n");
		return TCM_INVALID_CDB_FIELD;
	}

	return 0;
}

sense_reason_t
target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
{
	struct se_device *dev = cmd->se_dev;
	sense_reason_t ret;

	/*
	 * Ensure that the received CDB is less than the max (252 + 8) bytes
	 * for VARIABLE_LENGTH_CMD
	 */
	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
		pr_err("Received SCSI CDB with command_size: %d that"
			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
		return TCM_INVALID_CDB_FIELD;
	}
	/*
	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
	 * allocate the additional extended CDB buffer now..  Otherwise
	 * setup the pointer from __t_task_cdb to t_task_cdb.
	 */
	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
						GFP_KERNEL);
		if (!cmd->t_task_cdb) {
			pr_err("Unable to allocate cmd->t_task_cdb"
				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
				scsi_command_size(cdb),
				(unsigned long)sizeof(cmd->__t_task_cdb));
			return TCM_OUT_OF_RESOURCES;
		}
	} else
		cmd->t_task_cdb = &cmd->__t_task_cdb[0];
	/*
	 * Copy the original CDB into cmd->
	 */
	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));

	trace_target_sequencer_start(cmd);

	ret = dev->transport->parse_cdb(cmd);
	if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
		pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
				    cmd->se_tfo->get_fabric_name(),
				    cmd->se_sess->se_node_acl->initiatorname,
				    cmd->t_task_cdb[0]);
	if (ret)
		return ret;

	ret = transport_check_alloc_task_attr(cmd);
	if (ret)
		return ret;

	cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
	atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
	return 0;
}
EXPORT_SYMBOL(target_setup_cmd_from_cdb);

/*
 * Used by fabric module frontends to queue tasks directly.
 * May only be used from process context.
 */
int transport_handle_cdb_direct(
	struct se_cmd *cmd)
{
	sense_reason_t ret;

	if (!cmd->se_lun) {
		dump_stack();
		pr_err("cmd->se_lun is NULL\n");
		return -EINVAL;
	}
	if (in_interrupt()) {
		dump_stack();
		pr_err("transport_generic_handle_cdb cannot be called"
				" from interrupt context\n");
		return -EINVAL;
	}
	/*
	 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
	 * outstanding descriptors are handled correctly during shutdown via
	 * transport_wait_for_tasks()
	 *
	 * Also, we don't take cmd->t_state_lock here as we only expect
	 * this to be called for initial descriptor submission.
	 */
	cmd->t_state = TRANSPORT_NEW_CMD;
	cmd->transport_state |= CMD_T_ACTIVE;

	/*
	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
	 * so follow TRANSPORT_NEW_CMD processing thread context usage
	 * and call transport_generic_request_failure() if necessary..
	 */
	ret = transport_generic_new_cmd(cmd);
	if (ret)
		transport_generic_request_failure(cmd, ret);
	return 0;
}
EXPORT_SYMBOL(transport_handle_cdb_direct);

sense_reason_t
transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
		u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
{
	if (!sgl || !sgl_count)
		return 0;

	/*
	 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
	 * scatterlists already have been set to follow what the fabric
	 * passes for the original expected data transfer length.
	 */
	if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
		pr_warn("Rejecting SCSI DATA overflow for fabric using"
			" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
		return TCM_INVALID_CDB_FIELD;
	}

	cmd->t_data_sg = sgl;
	cmd->t_data_nents = sgl_count;
	cmd->t_bidi_data_sg = sgl_bidi;
	cmd->t_bidi_data_nents = sgl_bidi_count;

	cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
	return 0;
}

/**
 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
 * 			 se_cmd + use pre-allocated SGL memory.
 *
 * @se_cmd: command descriptor to submit
 * @se_sess: associated se_sess for endpoint
 * @cdb: pointer to SCSI CDB
 * @sense: pointer to SCSI sense buffer
 * @unpacked_lun: unpacked LUN to reference for struct se_lun
 * @data_length: fabric expected data transfer length
 * @task_attr: SAM task attribute
 * @data_dir: DMA data direction
 * @flags: flags for command submission from target_sc_flags_tables
 * @sgl: struct scatterlist memory for unidirectional mapping
 * @sgl_count: scatterlist count for unidirectional mapping
 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
 * @sgl_prot: struct scatterlist memory protection information
 * @sgl_prot_count: scatterlist count for protection information
 *
 * Task tags are supported if the caller has set @se_cmd->tag.
 *
 * Returns non zero to signal active I/O shutdown failure.  All other
 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
 * but still return zero here.
 *
 * This may only be called from process context, and also currently
 * assumes internal allocation of fabric payload buffer by target-core.
 */
int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
		unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
		u32 data_length, int task_attr, int data_dir, int flags,
		struct scatterlist *sgl, u32 sgl_count,
		struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
		struct scatterlist *sgl_prot, u32 sgl_prot_count)
{
	struct se_portal_group *se_tpg;
	sense_reason_t rc;
	int ret;

	se_tpg = se_sess->se_tpg;
	BUG_ON(!se_tpg);
	BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
	BUG_ON(in_interrupt());
	/*
	 * Initialize se_cmd for target operation.  From this point
	 * exceptions are handled by sending exception status via
	 * target_core_fabric_ops->queue_status() callback
	 */
	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
				data_length, data_dir, task_attr, sense);

	if (flags & TARGET_SCF_USE_CPUID)
		se_cmd->se_cmd_flags |= SCF_USE_CPUID;
	else
		se_cmd->cpuid = WORK_CPU_UNBOUND;

	if (flags & TARGET_SCF_UNKNOWN_SIZE)
		se_cmd->unknown_data_length = 1;
	/*
	 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
	 * se_sess->sess_cmd_list.  A second kref_get here is necessary
	 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
	 * kref_put() to happen during fabric packet acknowledgement.
	 */
	ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
	if (ret)
		return ret;
	/*
	 * Signal bidirectional data payloads to target-core
	 */
	if (flags & TARGET_SCF_BIDI_OP)
		se_cmd->se_cmd_flags |= SCF_BIDI;
	/*
	 * Locate se_lun pointer and attach it to struct se_cmd
	 */
	rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
	if (rc) {
		transport_send_check_condition_and_sense(se_cmd, rc, 0);
		target_put_sess_cmd(se_cmd);
		return 0;
	}

	rc = target_setup_cmd_from_cdb(se_cmd, cdb);
	if (rc != 0) {
		transport_generic_request_failure(se_cmd, rc);
		return 0;
	}

	/*
	 * Save pointers for SGLs containing protection information,
	 * if present.
	 */
	if (sgl_prot_count) {
		se_cmd->t_prot_sg = sgl_prot;
		se_cmd->t_prot_nents = sgl_prot_count;
		se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
	}

	/*
	 * When a non zero sgl_count has been passed perform SGL passthrough
	 * mapping for pre-allocated fabric memory instead of having target
	 * core perform an internal SGL allocation..
	 */
	if (sgl_count != 0) {
		BUG_ON(!sgl);

		/*
		 * A work-around for tcm_loop as some userspace code via
		 * scsi-generic do not memset their associated read buffers,
		 * so go ahead and do that here for type non-data CDBs.  Also
		 * note that this is currently guaranteed to be a single SGL
		 * for this case by target core in target_setup_cmd_from_cdb()
		 * -> transport_generic_cmd_sequencer().
		 */
		if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
		     se_cmd->data_direction == DMA_FROM_DEVICE) {
			unsigned char *buf = NULL;

			if (sgl)
				buf = kmap(sg_page(sgl)) + sgl->offset;

			if (buf) {
				memset(buf, 0, sgl->length);
				kunmap(sg_page(sgl));
			}
		}

		rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
				sgl_bidi, sgl_bidi_count);
		if (rc != 0) {
			transport_generic_request_failure(se_cmd, rc);
			return 0;
		}
	}

	/*
	 * Check if we need to delay processing because of ALUA
	 * Active/NonOptimized primary access state..
	 */
	core_alua_check_nonop_delay(se_cmd);

	transport_handle_cdb_direct(se_cmd);
	return 0;
}
EXPORT_SYMBOL(target_submit_cmd_map_sgls);

/**
 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
 *
 * @se_cmd: command descriptor to submit
 * @se_sess: associated se_sess for endpoint
 * @cdb: pointer to SCSI CDB
 * @sense: pointer to SCSI sense buffer
 * @unpacked_lun: unpacked LUN to reference for struct se_lun
 * @data_length: fabric expected data transfer length
 * @task_attr: SAM task attribute
 * @data_dir: DMA data direction
 * @flags: flags for command submission from target_sc_flags_tables
 *
 * Task tags are supported if the caller has set @se_cmd->tag.
 *
 * Returns non zero to signal active I/O shutdown failure.  All other
 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
 * but still return zero here.
 *
 * This may only be called from process context, and also currently
 * assumes internal allocation of fabric payload buffer by target-core.
 *
 * It also assumes interal target core SGL memory allocation.
 */
int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
		unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
		u32 data_length, int task_attr, int data_dir, int flags)
{
	return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
			unpacked_lun, data_length, task_attr, data_dir,
			flags, NULL, 0, NULL, 0, NULL, 0);
}
EXPORT_SYMBOL(target_submit_cmd);

static void target_complete_tmr_failure(struct work_struct *work)
{
	struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);

	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
	se_cmd->se_tfo->queue_tm_rsp(se_cmd);

	transport_lun_remove_cmd(se_cmd);
	transport_cmd_check_stop_to_fabric(se_cmd);
}

static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
				       u64 *unpacked_lun)
{
	struct se_cmd *se_cmd;
	unsigned long flags;
	bool ret = false;

	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
	list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
		if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
			continue;

		if (se_cmd->tag == tag) {
			*unpacked_lun = se_cmd->orig_fe_lun;
			ret = true;
			break;
		}
	}
	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);

	return ret;
}

/**
 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
 *                     for TMR CDBs
 *
 * @se_cmd: command descriptor to submit
 * @se_sess: associated se_sess for endpoint
 * @sense: pointer to SCSI sense buffer
 * @unpacked_lun: unpacked LUN to reference for struct se_lun
 * @fabric_tmr_ptr: fabric context for TMR req
 * @tm_type: Type of TM request
 * @gfp: gfp type for caller
 * @tag: referenced task tag for TMR_ABORT_TASK
 * @flags: submit cmd flags
 *
 * Callable from all contexts.
 **/

int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
		unsigned char *sense, u64 unpacked_lun,
		void *fabric_tmr_ptr, unsigned char tm_type,
		gfp_t gfp, u64 tag, int flags)
{
	struct se_portal_group *se_tpg;
	int ret;

	se_tpg = se_sess->se_tpg;
	BUG_ON(!se_tpg);

	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
			      0, DMA_NONE, TCM_SIMPLE_TAG, sense);
	/*
	 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
	 * allocation failure.
	 */
	ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
	if (ret < 0)
		return -ENOMEM;

	if (tm_type == TMR_ABORT_TASK)
		se_cmd->se_tmr_req->ref_task_tag = tag;

	/* See target_submit_cmd for commentary */
	ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
	if (ret) {
		core_tmr_release_req(se_cmd->se_tmr_req);
		return ret;
	}
	/*
	 * If this is ABORT_TASK with no explicit fabric provided LUN,
	 * go ahead and search active session tags for a match to figure
	 * out unpacked_lun for the original se_cmd.
	 */
	if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
		if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
			goto failure;
	}

	ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
	if (ret)
		goto failure;

	transport_generic_handle_tmr(se_cmd);
	return 0;

	/*
	 * For callback during failure handling, push this work off
	 * to process context with TMR_LUN_DOES_NOT_EXIST status.
	 */
failure:
	INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
	schedule_work(&se_cmd->work);
	return 0;
}
EXPORT_SYMBOL(target_submit_tmr);

/*
 * Handle SAM-esque emulation for generic transport request failures.
 */
void transport_generic_request_failure(struct se_cmd *cmd,
		sense_reason_t sense_reason)
{
	int ret = 0, post_ret;

	pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
		 sense_reason);
	target_show_cmd("-----[ ", cmd);

	/*
	 * For SAM Task Attribute emulation for failed struct se_cmd
	 */
	transport_complete_task_attr(cmd);

	if (cmd->transport_complete_callback)
		cmd->transport_complete_callback(cmd, false, &post_ret);

	if (transport_check_aborted_status(cmd, 1))
		return;

	switch (sense_reason) {
	case TCM_NON_EXISTENT_LUN:
	case TCM_UNSUPPORTED_SCSI_OPCODE:
	case TCM_INVALID_CDB_FIELD:
	case TCM_INVALID_PARAMETER_LIST:
	case TCM_PARAMETER_LIST_LENGTH_ERROR:
	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
	case TCM_UNKNOWN_MODE_PAGE:
	case TCM_WRITE_PROTECTED:
	case TCM_ADDRESS_OUT_OF_RANGE:
	case TCM_CHECK_CONDITION_ABORT_CMD:
	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
	case TCM_CHECK_CONDITION_NOT_READY:
	case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
	case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
	case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
	case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
	case TCM_TOO_MANY_TARGET_DESCS:
	case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
	case TCM_TOO_MANY_SEGMENT_DESCS:
	case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
		break;
	case TCM_OUT_OF_RESOURCES:
		cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
		goto queue_status;
	case TCM_LUN_BUSY:
		cmd->scsi_status = SAM_STAT_BUSY;
		goto queue_status;
	case TCM_RESERVATION_CONFLICT:
		/*
		 * No SENSE Data payload for this case, set SCSI Status
		 * and queue the response to $FABRIC_MOD.
		 *
		 * Uses linux/include/scsi/scsi.h SAM status codes defs
		 */
		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
		/*
		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
		 * CONFLICT STATUS.
		 *
		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
		 */
		if (cmd->se_sess &&
		    cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
			target_ua_allocate_lun(cmd->se_sess->se_node_acl,
					       cmd->orig_fe_lun, 0x2C,
					ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
		}

		goto queue_status;
	default:
		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
			cmd->t_task_cdb[0], sense_reason);
		sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
		break;
	}

	ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
	if (ret)
		goto queue_full;

check_stop:
	transport_lun_remove_cmd(cmd);
	transport_cmd_check_stop_to_fabric(cmd);
	return;

queue_status:
	trace_target_cmd_complete(cmd);
	ret = cmd->se_tfo->queue_status(cmd);
	if (!ret)
		goto check_stop;
queue_full:
	transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
}
EXPORT_SYMBOL(transport_generic_request_failure);

void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
{
	sense_reason_t ret;

	if (!cmd->execute_cmd) {
		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
		goto err;
	}
	if (do_checks) {
		/*
		 * Check for an existing UNIT ATTENTION condition after
		 * target_handle_task_attr() has done SAM task attr
		 * checking, and possibly have already defered execution
		 * out to target_restart_delayed_cmds() context.
		 */
		ret = target_scsi3_ua_check(cmd);
		if (ret)
			goto err;

		ret = target_alua_state_check(cmd);
		if (ret)
			goto err;

		ret = target_check_reservation(cmd);
		if (ret) {
			cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
			goto err;
		}
	}

	ret = cmd->execute_cmd(cmd);
	if (!ret)
		return;
err:
	spin_lock_irq(&cmd->t_state_lock);
	cmd->transport_state &= ~CMD_T_SENT;
	spin_unlock_irq(&cmd->t_state_lock);

	transport_generic_request_failure(cmd, ret);
}

static int target_write_prot_action(struct se_cmd *cmd)
{
	u32 sectors;
	/*
	 * Perform WRITE_INSERT of PI using software emulation when backend
	 * device has PI enabled, if the transport has not already generated
	 * PI using hardware WRITE_INSERT offload.
	 */
	switch (cmd->prot_op) {
	case TARGET_PROT_DOUT_INSERT:
		if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
			sbc_dif_generate(cmd);
		break;
	case TARGET_PROT_DOUT_STRIP:
		if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
			break;

		sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
		cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
					     sectors, 0, cmd->t_prot_sg, 0);
		if (unlikely(cmd->pi_err)) {
			spin_lock_irq(&cmd->t_state_lock);
			cmd->transport_state &= ~CMD_T_SENT;
			spin_unlock_irq(&cmd->t_state_lock);
			transport_generic_request_failure(cmd, cmd->pi_err);
			return -1;
		}
		break;
	default:
		break;
	}

	return 0;
}

static bool target_handle_task_attr(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;

	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
		return false;

	cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;

	/*
	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
	 * to allow the passed struct se_cmd list of tasks to the front of the list.
	 */
	switch (cmd->sam_task_attr) {
	case TCM_HEAD_TAG:
		pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
			 cmd->t_task_cdb[0]);
		return false;
	case TCM_ORDERED_TAG:
		atomic_inc_mb(&dev->dev_ordered_sync);

		pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
			 cmd->t_task_cdb[0]);

		/*
		 * Execute an ORDERED command if no other older commands
		 * exist that need to be completed first.
		 */
		if (!atomic_read(&dev->simple_cmds))
			return false;
		break;
	default:
		/*
		 * For SIMPLE and UNTAGGED Task Attribute commands
		 */
		atomic_inc_mb(&dev->simple_cmds);
		break;
	}

	if (atomic_read(&dev->dev_ordered_sync) == 0)
		return false;

	spin_lock(&dev->delayed_cmd_lock);
	list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
	spin_unlock(&dev->delayed_cmd_lock);

	pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
		cmd->t_task_cdb[0], cmd->sam_task_attr);
	return true;
}

static int __transport_check_aborted_status(struct se_cmd *, int);

void target_execute_cmd(struct se_cmd *cmd)
{
	/*
	 * Determine if frontend context caller is requesting the stopping of
	 * this command for frontend exceptions.
	 *
	 * If the received CDB has already been aborted stop processing it here.
	 */
	spin_lock_irq(&cmd->t_state_lock);
	if (__transport_check_aborted_status(cmd, 1)) {
		spin_unlock_irq(&cmd->t_state_lock);
		return;
	}
	if (cmd->transport_state & CMD_T_STOP) {
		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
			__func__, __LINE__, cmd->tag);

		spin_unlock_irq(&cmd->t_state_lock);
		complete_all(&cmd->t_transport_stop_comp);
		return;
	}

	cmd->t_state = TRANSPORT_PROCESSING;
	cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
	cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
	spin_unlock_irq(&cmd->t_state_lock);

	if (target_write_prot_action(cmd))
		return;

	if (target_handle_task_attr(cmd)) {
		spin_lock_irq(&cmd->t_state_lock);
		cmd->transport_state &= ~CMD_T_SENT;
		spin_unlock_irq(&cmd->t_state_lock);
		return;
	}

	__target_execute_cmd(cmd, true);
}
EXPORT_SYMBOL(target_execute_cmd);

/*
 * Process all commands up to the last received ORDERED task attribute which
 * requires another blocking boundary
 */
static void target_restart_delayed_cmds(struct se_device *dev)
{
	for (;;) {
		struct se_cmd *cmd;

		spin_lock(&dev->delayed_cmd_lock);
		if (list_empty(&dev->delayed_cmd_list)) {
			spin_unlock(&dev->delayed_cmd_lock);
			break;
		}

		cmd = list_entry(dev->delayed_cmd_list.next,
				 struct se_cmd, se_delayed_node);
		list_del(&cmd->se_delayed_node);
		spin_unlock(&dev->delayed_cmd_lock);

		cmd->transport_state |= CMD_T_SENT;

		__target_execute_cmd(cmd, true);

		if (cmd->sam_task_attr == TCM_ORDERED_TAG)
			break;
	}
}

/*
 * Called from I/O completion to determine which dormant/delayed
 * and ordered cmds need to have their tasks added to the execution queue.
 */
static void transport_complete_task_attr(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;

	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
		return;

	if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
		goto restart;

	if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
		atomic_dec_mb(&dev->simple_cmds);
		dev->dev_cur_ordered_id++;
	} else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
		dev->dev_cur_ordered_id++;
		pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
			 dev->dev_cur_ordered_id);
	} else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
		atomic_dec_mb(&dev->dev_ordered_sync);

		dev->dev_cur_ordered_id++;
		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
			 dev->dev_cur_ordered_id);
	}
	cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;

restart:
	target_restart_delayed_cmds(dev);
}

static void transport_complete_qf(struct se_cmd *cmd)
{
	int ret = 0;

	transport_complete_task_attr(cmd);
	/*
	 * If a fabric driver ->write_pending() or ->queue_data_in() callback
	 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
	 * the same callbacks should not be retried.  Return CHECK_CONDITION
	 * if a scsi_status is not already set.
	 *
	 * If a fabric driver ->queue_status() has returned non zero, always
	 * keep retrying no matter what..
	 */
	if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
		if (cmd->scsi_status)
			goto queue_status;

		translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
		goto queue_status;
	}

	/*
	 * Check if we need to send a sense buffer from
	 * the struct se_cmd in question. We do NOT want
	 * to take this path of the IO has been marked as
	 * needing to be treated like a "normal read". This
	 * is the case if it's a tape read, and either the
	 * FM, EOM, or ILI bits are set, but there is no
	 * sense data.
	 */
	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
		goto queue_status;

	switch (cmd->data_direction) {
	case DMA_FROM_DEVICE:
		/* queue status if not treating this as a normal read */
		if (cmd->scsi_status &&
		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
			goto queue_status;

		trace_target_cmd_complete(cmd);
		ret = cmd->se_tfo->queue_data_in(cmd);
		break;
	case DMA_TO_DEVICE:
		if (cmd->se_cmd_flags & SCF_BIDI) {
			ret = cmd->se_tfo->queue_data_in(cmd);
			break;
		}
		/* fall through */
	case DMA_NONE:
queue_status:
		trace_target_cmd_complete(cmd);
		ret = cmd->se_tfo->queue_status(cmd);
		break;
	default:
		break;
	}

	if (ret < 0) {
		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
		return;
	}
	transport_lun_remove_cmd(cmd);
	transport_cmd_check_stop_to_fabric(cmd);
}

static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
					int err, bool write_pending)
{
	/*
	 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
	 * ->queue_data_in() callbacks from new process context.
	 *
	 * Otherwise for other errors, transport_complete_qf() will send
	 * CHECK_CONDITION via ->queue_status() instead of attempting to
	 * retry associated fabric driver data-transfer callbacks.
	 */
	if (err == -EAGAIN || err == -ENOMEM) {
		cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
						 TRANSPORT_COMPLETE_QF_OK;
	} else {
		pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
		cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
	}

	spin_lock_irq(&dev->qf_cmd_lock);
	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
	atomic_inc_mb(&dev->dev_qf_count);
	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);

	schedule_work(&cmd->se_dev->qf_work_queue);
}

static bool target_read_prot_action(struct se_cmd *cmd)
{
	switch (cmd->prot_op) {
	case TARGET_PROT_DIN_STRIP:
		if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
			u32 sectors = cmd->data_length >>
				  ilog2(cmd->se_dev->dev_attrib.block_size);

			cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
						     sectors, 0, cmd->t_prot_sg,
						     0);
			if (cmd->pi_err)
				return true;
		}
		break;
	case TARGET_PROT_DIN_INSERT:
		if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
			break;

		sbc_dif_generate(cmd);
		break;
	default:
		break;
	}

	return false;
}

static void target_complete_ok_work(struct work_struct *work)
{
	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
	int ret;

	/*
	 * Check if we need to move delayed/dormant tasks from cmds on the
	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
	 * Attribute.
	 */
	transport_complete_task_attr(cmd);

	/*
	 * Check to schedule QUEUE_FULL work, or execute an existing
	 * cmd->transport_qf_callback()
	 */
	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
		schedule_work(&cmd->se_dev->qf_work_queue);

	/*
	 * Check if we need to send a sense buffer from
	 * the struct se_cmd in question. We do NOT want
	 * to take this path of the IO has been marked as
	 * needing to be treated like a "normal read". This
	 * is the case if it's a tape read, and either the
	 * FM, EOM, or ILI bits are set, but there is no
	 * sense data.
	 */
	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
		WARN_ON(!cmd->scsi_status);
		ret = transport_send_check_condition_and_sense(
					cmd, 0, 1);
		if (ret)
			goto queue_full;

		transport_lun_remove_cmd(cmd);
		transport_cmd_check_stop_to_fabric(cmd);
		return;
	}
	/*
	 * Check for a callback, used by amongst other things
	 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
	 */
	if (cmd->transport_complete_callback) {
		sense_reason_t rc;
		bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
		bool zero_dl = !(cmd->data_length);
		int post_ret = 0;

		rc = cmd->transport_complete_callback(cmd, true, &post_ret);
		if (!rc && !post_ret) {
			if (caw && zero_dl)
				goto queue_rsp;

			return;
		} else if (rc) {
			ret = transport_send_check_condition_and_sense(cmd,
						rc, 0);
			if (ret)
				goto queue_full;

			transport_lun_remove_cmd(cmd);
			transport_cmd_check_stop_to_fabric(cmd);
			return;
		}
	}

queue_rsp:
	switch (cmd->data_direction) {
	case DMA_FROM_DEVICE:
		/*
		 * if this is a READ-type IO, but SCSI status
		 * is set, then skip returning data and just
		 * return the status -- unless this IO is marked
		 * as needing to be treated as a normal read,
		 * in which case we want to go ahead and return
		 * the data. This happens, for example, for tape
		 * reads with the FM, EOM, or ILI bits set, with
		 * no sense data.
		 */
		if (cmd->scsi_status &&
		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
			goto queue_status;

		atomic_long_add(cmd->data_length,
				&cmd->se_lun->lun_stats.tx_data_octets);
		/*
		 * Perform READ_STRIP of PI using software emulation when
		 * backend had PI enabled, if the transport will not be
		 * performing hardware READ_STRIP offload.
		 */
		if (target_read_prot_action(cmd)) {
			ret = transport_send_check_condition_and_sense(cmd,
						cmd->pi_err, 0);
			if (ret)
				goto queue_full;

			transport_lun_remove_cmd(cmd);
			transport_cmd_check_stop_to_fabric(cmd);
			return;
		}

		trace_target_cmd_complete(cmd);
		ret = cmd->se_tfo->queue_data_in(cmd);
		if (ret)
			goto queue_full;
		break;
	case DMA_TO_DEVICE:
		atomic_long_add(cmd->data_length,
				&cmd->se_lun->lun_stats.rx_data_octets);
		/*
		 * Check if we need to send READ payload for BIDI-COMMAND
		 */
		if (cmd->se_cmd_flags & SCF_BIDI) {
			atomic_long_add(cmd->data_length,
					&cmd->se_lun->lun_stats.tx_data_octets);
			ret = cmd->se_tfo->queue_data_in(cmd);
			if (ret)
				goto queue_full;
			break;
		}
		/* fall through */
	case DMA_NONE:
queue_status:
		trace_target_cmd_complete(cmd);
		ret = cmd->se_tfo->queue_status(cmd);
		if (ret)
			goto queue_full;
		break;
	default:
		break;
	}

	transport_lun_remove_cmd(cmd);
	transport_cmd_check_stop_to_fabric(cmd);
	return;

queue_full:
	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
		" data_direction: %d\n", cmd, cmd->data_direction);

	transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
}

void target_free_sgl(struct scatterlist *sgl, int nents)
{
	sgl_free_n_order(sgl, nents, 0);
}
EXPORT_SYMBOL(target_free_sgl);

static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
{
	/*
	 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
	 * emulation, and free + reset pointers if necessary..
	 */
	if (!cmd->t_data_sg_orig)
		return;

	kfree(cmd->t_data_sg);
	cmd->t_data_sg = cmd->t_data_sg_orig;
	cmd->t_data_sg_orig = NULL;
	cmd->t_data_nents = cmd->t_data_nents_orig;
	cmd->t_data_nents_orig = 0;
}

static inline void transport_free_pages(struct se_cmd *cmd)
{
	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
		target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
		cmd->t_prot_sg = NULL;
		cmd->t_prot_nents = 0;
	}

	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
		/*
		 * Release special case READ buffer payload required for
		 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
		 */
		if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
			target_free_sgl(cmd->t_bidi_data_sg,
					   cmd->t_bidi_data_nents);
			cmd->t_bidi_data_sg = NULL;
			cmd->t_bidi_data_nents = 0;
		}
		transport_reset_sgl_orig(cmd);
		return;
	}
	transport_reset_sgl_orig(cmd);

	target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
	cmd->t_data_sg = NULL;
	cmd->t_data_nents = 0;

	target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
	cmd->t_bidi_data_sg = NULL;
	cmd->t_bidi_data_nents = 0;
}

void *transport_kmap_data_sg(struct se_cmd *cmd)
{
	struct scatterlist *sg = cmd->t_data_sg;
	struct page **pages;
	int i;

	/*
	 * We need to take into account a possible offset here for fabrics like
	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
	 */
	if (!cmd->t_data_nents)
		return NULL;

	BUG_ON(!sg);
	if (cmd->t_data_nents == 1)
		return kmap(sg_page(sg)) + sg->offset;

	/* >1 page. use vmap */
	pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
	if (!pages)
		return NULL;

	/* convert sg[] to pages[] */
	for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
		pages[i] = sg_page(sg);
	}

	cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
	kfree(pages);
	if (!cmd->t_data_vmap)
		return NULL;

	return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
}
EXPORT_SYMBOL(transport_kmap_data_sg);

void transport_kunmap_data_sg(struct se_cmd *cmd)
{
	if (!cmd->t_data_nents) {
		return;
	} else if (cmd->t_data_nents == 1) {
		kunmap(sg_page(cmd->t_data_sg));
		return;
	}

	vunmap(cmd->t_data_vmap);
	cmd->t_data_vmap = NULL;
}
EXPORT_SYMBOL(transport_kunmap_data_sg);

int
target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
		 bool zero_page, bool chainable)
{
	gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);

	*sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
	return *sgl ? 0 : -ENOMEM;
}
EXPORT_SYMBOL(target_alloc_sgl);

/*
 * Allocate any required resources to execute the command.  For writes we
 * might not have the payload yet, so notify the fabric via a call to
 * ->write_pending instead. Otherwise place it on the execution queue.
 */
sense_reason_t
transport_generic_new_cmd(struct se_cmd *cmd)
{
	unsigned long flags;
	int ret = 0;
	bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);

	if (cmd->prot_op != TARGET_PROT_NORMAL &&
	    !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
		ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
				       cmd->prot_length, true, false);
		if (ret < 0)
			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
	}

	/*
	 * Determine if the TCM fabric module has already allocated physical
	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
	 * beforehand.
	 */
	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
	    cmd->data_length) {

		if ((cmd->se_cmd_flags & SCF_BIDI) ||
		    (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
			u32 bidi_length;

			if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
				bidi_length = cmd->t_task_nolb *
					      cmd->se_dev->dev_attrib.block_size;
			else
				bidi_length = cmd->data_length;

			ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
					       &cmd->t_bidi_data_nents,
					       bidi_length, zero_flag, false);
			if (ret < 0)
				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
		}

		ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
				       cmd->data_length, zero_flag, false);
		if (ret < 0)
			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
	} else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
		    cmd->data_length) {
		/*
		 * Special case for COMPARE_AND_WRITE with fabrics
		 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
		 */
		u32 caw_length = cmd->t_task_nolb *
				 cmd->se_dev->dev_attrib.block_size;

		ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
				       &cmd->t_bidi_data_nents,
				       caw_length, zero_flag, false);
		if (ret < 0)
			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
	}
	/*
	 * If this command is not a write we can execute it right here,
	 * for write buffers we need to notify the fabric driver first
	 * and let it call back once the write buffers are ready.
	 */
	target_add_to_state_list(cmd);
	if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
		target_execute_cmd(cmd);
		return 0;
	}

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	cmd->t_state = TRANSPORT_WRITE_PENDING;
	/*
	 * Determine if frontend context caller is requesting the stopping of
	 * this command for frontend exceptions.
	 */
	if (cmd->transport_state & CMD_T_STOP) {
		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
			 __func__, __LINE__, cmd->tag);

		spin_unlock_irqrestore(&cmd->t_state_lock, flags);

		complete_all(&cmd->t_transport_stop_comp);
		return 0;
	}
	cmd->transport_state &= ~CMD_T_ACTIVE;
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	ret = cmd->se_tfo->write_pending(cmd);
	if (ret)
		goto queue_full;

	return 0;

queue_full:
	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
	transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
	return 0;
}
EXPORT_SYMBOL(transport_generic_new_cmd);

static void transport_write_pending_qf(struct se_cmd *cmd)
{
	unsigned long flags;
	int ret;
	bool stop;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	if (stop) {
		pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
			__func__, __LINE__, cmd->tag);
		complete_all(&cmd->t_transport_stop_comp);
		return;
	}

	ret = cmd->se_tfo->write_pending(cmd);
	if (ret) {
		pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
			 cmd);
		transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
	}
}

static bool
__transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
			   unsigned long *flags);

static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
{
	unsigned long flags;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	__transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}

/*
 * This function is called by frontend drivers after processing of a command
 * has finished.
 *
 * The protocol for ensuring that either the regular flow or the TMF
 * code drops one reference is as follows:
 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
 *   the frontend driver to drop one reference, synchronously or asynchronously.
 * - During regular command processing the target core sets CMD_T_COMPLETE
 *   before invoking one of the .queue_*() functions.
 * - The code that aborts commands skips commands and TMFs for which
 *   CMD_T_COMPLETE has been set.
 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
 *   commands that will be aborted.
 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
 *   transport_generic_free_cmd() skips its call to target_put_sess_cmd().
 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
 *   be called and will drop a reference.
 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
 *   will be called. transport_cmd_finish_abort() will drop the final reference.
 */
int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
{
	DECLARE_COMPLETION_ONSTACK(compl);
	int ret = 0;
	bool aborted = false, tas = false;

	if (wait_for_tasks)
		target_wait_free_cmd(cmd, &aborted, &tas);

	if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
		/*
		 * Handle WRITE failure case where transport_generic_new_cmd()
		 * has already added se_cmd to state_list, but fabric has
		 * failed command before I/O submission.
		 */
		if (cmd->state_active)
			target_remove_from_state_list(cmd);

		if (cmd->se_lun)
			transport_lun_remove_cmd(cmd);
	}
	if (aborted)
		cmd->compl = &compl;
	if (!aborted || tas)
		ret = target_put_sess_cmd(cmd);
	if (aborted) {
		pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
		wait_for_completion(&compl);
		ret = 1;
	}
	return ret;
}
EXPORT_SYMBOL(transport_generic_free_cmd);

/**
 * target_get_sess_cmd - Add command to active ->sess_cmd_list
 * @se_cmd:	command descriptor to add
 * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
 */
int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
{
	struct se_session *se_sess = se_cmd->se_sess;
	unsigned long flags;
	int ret = 0;

	/*
	 * Add a second kref if the fabric caller is expecting to handle
	 * fabric acknowledgement that requires two target_put_sess_cmd()
	 * invocations before se_cmd descriptor release.
	 */
	if (ack_kref) {
		if (!kref_get_unless_zero(&se_cmd->cmd_kref))
			return -EINVAL;

		se_cmd->se_cmd_flags |= SCF_ACK_KREF;
	}

	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
	if (se_sess->sess_tearing_down) {
		ret = -ESHUTDOWN;
		goto out;
	}
	se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
	list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
out:
	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);

	if (ret && ack_kref)
		target_put_sess_cmd(se_cmd);

	return ret;
}
EXPORT_SYMBOL(target_get_sess_cmd);

static void target_free_cmd_mem(struct se_cmd *cmd)
{
	transport_free_pages(cmd);

	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
		core_tmr_release_req(cmd->se_tmr_req);
	if (cmd->t_task_cdb != cmd->__t_task_cdb)
		kfree(cmd->t_task_cdb);
}

static void target_release_cmd_kref(struct kref *kref)
{
	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
	struct se_session *se_sess = se_cmd->se_sess;
	struct completion *compl = se_cmd->compl;
	unsigned long flags;

	if (se_sess) {
		spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
		list_del_init(&se_cmd->se_cmd_list);
		if (se_sess->sess_tearing_down && list_empty(&se_sess->sess_cmd_list))
			wake_up(&se_sess->cmd_list_wq);
		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
	}

	target_free_cmd_mem(se_cmd);
	se_cmd->se_tfo->release_cmd(se_cmd);
	if (compl)
		complete(compl);
}

/**
 * target_put_sess_cmd - decrease the command reference count
 * @se_cmd:	command to drop a reference from
 *
 * Returns 1 if and only if this target_put_sess_cmd() call caused the
 * refcount to drop to zero. Returns zero otherwise.
 */
int target_put_sess_cmd(struct se_cmd *se_cmd)
{
	return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
}
EXPORT_SYMBOL(target_put_sess_cmd);

static const char *data_dir_name(enum dma_data_direction d)
{
	switch (d) {
	case DMA_BIDIRECTIONAL:	return "BIDI";
	case DMA_TO_DEVICE:	return "WRITE";
	case DMA_FROM_DEVICE:	return "READ";
	case DMA_NONE:		return "NONE";
	}

	return "(?)";
}

static const char *cmd_state_name(enum transport_state_table t)
{
	switch (t) {
	case TRANSPORT_NO_STATE:	return "NO_STATE";
	case TRANSPORT_NEW_CMD:		return "NEW_CMD";
	case TRANSPORT_WRITE_PENDING:	return "WRITE_PENDING";
	case TRANSPORT_PROCESSING:	return "PROCESSING";
	case TRANSPORT_COMPLETE:	return "COMPLETE";
	case TRANSPORT_ISTATE_PROCESSING:
					return "ISTATE_PROCESSING";
	case TRANSPORT_COMPLETE_QF_WP:	return "COMPLETE_QF_WP";
	case TRANSPORT_COMPLETE_QF_OK:	return "COMPLETE_QF_OK";
	case TRANSPORT_COMPLETE_QF_ERR:	return "COMPLETE_QF_ERR";
	}

	return "(?)";
}

static void target_append_str(char **str, const char *txt)
{
	char *prev = *str;

	*str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
		kstrdup(txt, GFP_ATOMIC);
	kfree(prev);
}

/*
 * Convert a transport state bitmask into a string. The caller is
 * responsible for freeing the returned pointer.
 */
static char *target_ts_to_str(u32 ts)
{
	char *str = NULL;

	if (ts & CMD_T_ABORTED)
		target_append_str(&str, "aborted");
	if (ts & CMD_T_ACTIVE)
		target_append_str(&str, "active");
	if (ts & CMD_T_COMPLETE)
		target_append_str(&str, "complete");
	if (ts & CMD_T_SENT)
		target_append_str(&str, "sent");
	if (ts & CMD_T_STOP)
		target_append_str(&str, "stop");
	if (ts & CMD_T_FABRIC_STOP)
		target_append_str(&str, "fabric_stop");

	return str;
}

static const char *target_tmf_name(enum tcm_tmreq_table tmf)
{
	switch (tmf) {
	case TMR_ABORT_TASK:		return "ABORT_TASK";
	case TMR_ABORT_TASK_SET:	return "ABORT_TASK_SET";
	case TMR_CLEAR_ACA:		return "CLEAR_ACA";
	case TMR_CLEAR_TASK_SET:	return "CLEAR_TASK_SET";
	case TMR_LUN_RESET:		return "LUN_RESET";
	case TMR_TARGET_WARM_RESET:	return "TARGET_WARM_RESET";
	case TMR_TARGET_COLD_RESET:	return "TARGET_COLD_RESET";
	case TMR_UNKNOWN:		break;
	}
	return "(?)";
}

void target_show_cmd(const char *pfx, struct se_cmd *cmd)
{
	char *ts_str = target_ts_to_str(cmd->transport_state);
	const u8 *cdb = cmd->t_task_cdb;
	struct se_tmr_req *tmf = cmd->se_tmr_req;

	if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
		pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
			 pfx, cdb[0], cdb[1], cmd->tag,
			 data_dir_name(cmd->data_direction),
			 cmd->se_tfo->get_cmd_state(cmd),
			 cmd_state_name(cmd->t_state), cmd->data_length,
			 kref_read(&cmd->cmd_kref), ts_str);
	} else {
		pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
			 pfx, target_tmf_name(tmf->function), cmd->tag,
			 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
			 cmd_state_name(cmd->t_state),
			 kref_read(&cmd->cmd_kref), ts_str);
	}
	kfree(ts_str);
}
EXPORT_SYMBOL(target_show_cmd);

/**
 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
 * @se_sess:	session to flag
 */
void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
{
	unsigned long flags;

	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
	se_sess->sess_tearing_down = 1;
	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
}
EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);

/**
 * target_wait_for_sess_cmds - Wait for outstanding commands
 * @se_sess:    session to wait for active I/O
 */
void target_wait_for_sess_cmds(struct se_session *se_sess)
{
	struct se_cmd *cmd;
	int ret;

	WARN_ON_ONCE(!se_sess->sess_tearing_down);

	spin_lock_irq(&se_sess->sess_cmd_lock);
	do {
		ret = wait_event_lock_irq_timeout(
				se_sess->cmd_list_wq,
				list_empty(&se_sess->sess_cmd_list),
				se_sess->sess_cmd_lock, 180 * HZ);
		list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
			target_show_cmd("session shutdown: still waiting for ",
					cmd);
	} while (ret <= 0);
	spin_unlock_irq(&se_sess->sess_cmd_lock);
}
EXPORT_SYMBOL(target_wait_for_sess_cmds);

static void target_lun_confirm(struct percpu_ref *ref)
{
	struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);

	complete(&lun->lun_ref_comp);
}

void transport_clear_lun_ref(struct se_lun *lun)
{
	/*
	 * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
	 * the initial reference and schedule confirm kill to be
	 * executed after one full RCU grace period has completed.
	 */
	percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
	/*
	 * The first completion waits for percpu_ref_switch_to_atomic_rcu()
	 * to call target_lun_confirm after lun->lun_ref has been marked
	 * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
	 * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
	 * fails for all new incoming I/O.
	 */
	wait_for_completion(&lun->lun_ref_comp);
	/*
	 * The second completion waits for percpu_ref_put_many() to
	 * invoke ->release() after lun->lun_ref has switched to
	 * atomic_t mode, and lun->lun_ref.count has reached zero.
	 *
	 * At this point all target-core lun->lun_ref references have
	 * been dropped via transport_lun_remove_cmd(), and it's safe
	 * to proceed with the remaining LUN shutdown.
	 */
	wait_for_completion(&lun->lun_shutdown_comp);
}

static bool
__transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
			   bool *aborted, bool *tas, unsigned long *flags)
	__releases(&cmd->t_state_lock)
	__acquires(&cmd->t_state_lock)
{

	assert_spin_locked(&cmd->t_state_lock);
	WARN_ON_ONCE(!irqs_disabled());

	if (fabric_stop)
		cmd->transport_state |= CMD_T_FABRIC_STOP;

	if (cmd->transport_state & CMD_T_ABORTED)
		*aborted = true;

	if (cmd->transport_state & CMD_T_TAS)
		*tas = true;

	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
		return false;

	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
		return false;

	if (!(cmd->transport_state & CMD_T_ACTIVE))
		return false;

	if (fabric_stop && *aborted)
		return false;

	cmd->transport_state |= CMD_T_STOP;

	target_show_cmd("wait_for_tasks: Stopping ", cmd);

	spin_unlock_irqrestore(&cmd->t_state_lock, *flags);

	while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
					    180 * HZ))
		target_show_cmd("wait for tasks: ", cmd);

	spin_lock_irqsave(&cmd->t_state_lock, *flags);
	cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);

	pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
		 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);

	return true;
}

/**
 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
 * @cmd: command to wait on
 */
bool transport_wait_for_tasks(struct se_cmd *cmd)
{
	unsigned long flags;
	bool ret, aborted = false, tas = false;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	return ret;
}
EXPORT_SYMBOL(transport_wait_for_tasks);

struct sense_info {
	u8 key;
	u8 asc;
	u8 ascq;
	bool add_sector_info;
};

static const struct sense_info sense_info_table[] = {
	[TCM_NO_SENSE] = {
		.key = NOT_READY
	},
	[TCM_NON_EXISTENT_LUN] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
	},
	[TCM_UNSUPPORTED_SCSI_OPCODE] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x20, /* INVALID COMMAND OPERATION CODE */
	},
	[TCM_SECTOR_COUNT_TOO_MANY] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x20, /* INVALID COMMAND OPERATION CODE */
	},
	[TCM_UNKNOWN_MODE_PAGE] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x24, /* INVALID FIELD IN CDB */
	},
	[TCM_CHECK_CONDITION_ABORT_CMD] = {
		.key = ABORTED_COMMAND,
		.asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
		.ascq = 0x03,
	},
	[TCM_INCORRECT_AMOUNT_OF_DATA] = {
		.key = ABORTED_COMMAND,
		.asc = 0x0c, /* WRITE ERROR */
		.ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
	},
	[TCM_INVALID_CDB_FIELD] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x24, /* INVALID FIELD IN CDB */
	},
	[TCM_INVALID_PARAMETER_LIST] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
	},
	[TCM_TOO_MANY_TARGET_DESCS] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x26,
		.ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
	},
	[TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x26,
		.ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
	},
	[TCM_TOO_MANY_SEGMENT_DESCS] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x26,
		.ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
	},
	[TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x26,
		.ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
	},
	[TCM_PARAMETER_LIST_LENGTH_ERROR] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
	},
	[TCM_UNEXPECTED_UNSOLICITED_DATA] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x0c, /* WRITE ERROR */
		.ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
	},
	[TCM_SERVICE_CRC_ERROR] = {
		.key = ABORTED_COMMAND,
		.asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
		.ascq = 0x05, /* N/A */
	},
	[TCM_SNACK_REJECTED] = {
		.key = ABORTED_COMMAND,
		.asc = 0x11, /* READ ERROR */
		.ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
	},
	[TCM_WRITE_PROTECTED] = {
		.key = DATA_PROTECT,
		.asc = 0x27, /* WRITE PROTECTED */
	},
	[TCM_ADDRESS_OUT_OF_RANGE] = {
		.key = ILLEGAL_REQUEST,
		.asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
	},
	[TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
		.key = UNIT_ATTENTION,
	},
	[TCM_CHECK_CONDITION_NOT_READY] = {
		.key = NOT_READY,
	},
	[TCM_MISCOMPARE_VERIFY] = {
		.key = MISCOMPARE,
		.asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
		.ascq = 0x00,
	},
	[TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
		.key = ABORTED_COMMAND,
		.asc = 0x10,
		.ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
		.add_sector_info = true,
	},
	[TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
		.key = ABORTED_COMMAND,
		.asc = 0x10,
		.ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
		.add_sector_info = true,
	},
	[TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
		.key = ABORTED_COMMAND,
		.asc = 0x10,
		.ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
		.add_sector_info = true,
	},
	[TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
		.key = COPY_ABORTED,
		.asc = 0x0d,
		.ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */

	},
	[TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
		/*
		 * Returning ILLEGAL REQUEST would cause immediate IO errors on
		 * Solaris initiators.  Returning NOT READY instead means the
		 * operations will be retried a finite number of times and we
		 * can survive intermittent errors.
		 */
		.key = NOT_READY,
		.asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
	},
	[TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
		/*
		 * From spc4r22 section5.7.7,5.7.8
		 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
		 * or a REGISTER AND IGNORE EXISTING KEY service action or
		 * REGISTER AND MOVE service actionis attempted,
		 * but there are insufficient device server resources to complete the
		 * operation, then the command shall be terminated with CHECK CONDITION
		 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
		 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
		 */
		.key = ILLEGAL_REQUEST,
		.asc = 0x55,
		.ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
	},
};

/**
 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
 *   be stored.
 * @reason: LIO sense reason code. If this argument has the value
 *   TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
 *   dequeuing a unit attention fails due to multiple commands being processed
 *   concurrently, set the command status to BUSY.
 *
 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
 */
static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
{
	const struct sense_info *si;
	u8 *buffer = cmd->sense_buffer;
	int r = (__force int)reason;
	u8 key, asc, ascq;
	bool desc_format = target_sense_desc_format(cmd->se_dev);

	if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
		si = &sense_info_table[r];
	else
		si = &sense_info_table[(__force int)
				       TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];

	key = si->key;
	if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
		if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
						       &ascq)) {
			cmd->scsi_status = SAM_STAT_BUSY;
			return;
		}
	} else if (si->asc == 0) {
		WARN_ON_ONCE(cmd->scsi_asc == 0);
		asc = cmd->scsi_asc;
		ascq = cmd->scsi_ascq;
	} else {
		asc = si->asc;
		ascq = si->ascq;
	}

	cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
	scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
	if (si->add_sector_info)
		WARN_ON_ONCE(scsi_set_sense_information(buffer,
							cmd->scsi_sense_length,
							cmd->bad_sector) < 0);
}

int
transport_send_check_condition_and_sense(struct se_cmd *cmd,
		sense_reason_t reason, int from_transport)
{
	unsigned long flags;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		return 0;
	}
	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	if (!from_transport)
		translate_sense_reason(cmd, reason);

	trace_target_cmd_complete(cmd);
	return cmd->se_tfo->queue_status(cmd);
}
EXPORT_SYMBOL(transport_send_check_condition_and_sense);

static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
	__releases(&cmd->t_state_lock)
	__acquires(&cmd->t_state_lock)
{
	int ret;

	assert_spin_locked(&cmd->t_state_lock);
	WARN_ON_ONCE(!irqs_disabled());

	if (!(cmd->transport_state & CMD_T_ABORTED))
		return 0;
	/*
	 * If cmd has been aborted but either no status is to be sent or it has
	 * already been sent, just return
	 */
	if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
		if (send_status)
			cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
		return 1;
	}

	pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
		" 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);

	cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
	trace_target_cmd_complete(cmd);

	spin_unlock_irq(&cmd->t_state_lock);
	ret = cmd->se_tfo->queue_status(cmd);
	if (ret)
		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
	spin_lock_irq(&cmd->t_state_lock);

	return 1;
}

int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
{
	int ret;

	spin_lock_irq(&cmd->t_state_lock);
	ret = __transport_check_aborted_status(cmd, send_status);
	spin_unlock_irq(&cmd->t_state_lock);

	return ret;
}
EXPORT_SYMBOL(transport_check_aborted_status);

void transport_send_task_abort(struct se_cmd *cmd)
{
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		return;
	}
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	/*
	 * If there are still expected incoming fabric WRITEs, we wait
	 * until until they have completed before sending a TASK_ABORTED
	 * response.  This response with TASK_ABORTED status will be
	 * queued back to fabric module by transport_check_aborted_status().
	 */
	if (cmd->data_direction == DMA_TO_DEVICE) {
		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
			spin_lock_irqsave(&cmd->t_state_lock, flags);
			if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
				spin_unlock_irqrestore(&cmd->t_state_lock, flags);
				goto send_abort;
			}
			cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
			spin_unlock_irqrestore(&cmd->t_state_lock, flags);
			return;
		}
	}
send_abort:
	cmd->scsi_status = SAM_STAT_TASK_ABORTED;

	transport_lun_remove_cmd(cmd);

	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
		 cmd->t_task_cdb[0], cmd->tag);

	trace_target_cmd_complete(cmd);
	ret = cmd->se_tfo->queue_status(cmd);
	if (ret)
		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
}

static void target_tmr_work(struct work_struct *work)
{
	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
	struct se_device *dev = cmd->se_dev;
	struct se_tmr_req *tmr = cmd->se_tmr_req;
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	if (cmd->transport_state & CMD_T_ABORTED) {
		tmr->response = TMR_FUNCTION_REJECTED;
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		goto check_stop;
	}
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	switch (tmr->function) {
	case TMR_ABORT_TASK:
		core_tmr_abort_task(dev, tmr, cmd->se_sess);
		break;
	case TMR_ABORT_TASK_SET:
	case TMR_CLEAR_ACA:
	case TMR_CLEAR_TASK_SET:
		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
		break;
	case TMR_LUN_RESET:
		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
					 TMR_FUNCTION_REJECTED;
		if (tmr->response == TMR_FUNCTION_COMPLETE) {
			target_ua_allocate_lun(cmd->se_sess->se_node_acl,
					       cmd->orig_fe_lun, 0x29,
					       ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
		}
		break;
	case TMR_TARGET_WARM_RESET:
		tmr->response = TMR_FUNCTION_REJECTED;
		break;
	case TMR_TARGET_COLD_RESET:
		tmr->response = TMR_FUNCTION_REJECTED;
		break;
	default:
		pr_err("Unknown TMR function: 0x%02x.\n",
				tmr->function);
		tmr->response = TMR_FUNCTION_REJECTED;
		break;
	}

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	if (cmd->transport_state & CMD_T_ABORTED) {
		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
		goto check_stop;
	}
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	cmd->se_tfo->queue_tm_rsp(cmd);

check_stop:
	transport_lun_remove_cmd(cmd);
	transport_cmd_check_stop_to_fabric(cmd);
}

int transport_generic_handle_tmr(
	struct se_cmd *cmd)
{
	unsigned long flags;
	bool aborted = false;

	spin_lock_irqsave(&cmd->t_state_lock, flags);
	if (cmd->transport_state & CMD_T_ABORTED) {
		aborted = true;
	} else {
		cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
		cmd->transport_state |= CMD_T_ACTIVE;
	}
	spin_unlock_irqrestore(&cmd->t_state_lock, flags);

	if (aborted) {
		pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
			"ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
			cmd->se_tmr_req->ref_task_tag, cmd->tag);
		transport_lun_remove_cmd(cmd);
		transport_cmd_check_stop_to_fabric(cmd);
		return 0;
	}

	INIT_WORK(&cmd->work, target_tmr_work);
	queue_work(cmd->se_dev->tmr_wq, &cmd->work);
	return 0;
}
EXPORT_SYMBOL(transport_generic_handle_tmr);

bool
target_check_wce(struct se_device *dev)
{
	bool wce = false;

	if (dev->transport->get_write_cache)
		wce = dev->transport->get_write_cache(dev);
	else if (dev->dev_attrib.emulate_write_cache > 0)
		wce = true;

	return wce;
}

bool
target_check_fua(struct se_device *dev)
{
	return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
}
OpenPOWER on IntegriCloud