aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/i915_gem.c
blob: 5f614828d365555f70005aff470117ab15b3ae12 (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
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
/*
 * Copyright © 2008 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */

#include <drm/drmP.h>
#include <drm/drm_vma_manager.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
#include "i915_trace.h"
#include "intel_drv.h"
#include <linux/oom.h>
#include <linux/shmem_fs.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/pci.h>
#include <linux/dma-buf.h>

static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj,
						   bool force);
static __must_check int
i915_gem_object_wait_rendering(struct drm_i915_gem_object *obj,
			       bool readonly);
static void
i915_gem_object_retire(struct drm_i915_gem_object *obj);

static void i915_gem_write_fence(struct drm_device *dev, int reg,
				 struct drm_i915_gem_object *obj);
static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj,
					 struct drm_i915_fence_reg *fence,
					 bool enable);

static unsigned long i915_gem_shrinker_count(struct shrinker *shrinker,
					     struct shrink_control *sc);
static unsigned long i915_gem_shrinker_scan(struct shrinker *shrinker,
					    struct shrink_control *sc);
static int i915_gem_shrinker_oom(struct notifier_block *nb,
				 unsigned long event,
				 void *ptr);
static unsigned long i915_gem_shrink_all(struct drm_i915_private *dev_priv);

static bool cpu_cache_is_coherent(struct drm_device *dev,
				  enum i915_cache_level level)
{
	return HAS_LLC(dev) || level != I915_CACHE_NONE;
}

static bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
{
	if (!cpu_cache_is_coherent(obj->base.dev, obj->cache_level))
		return true;

	return obj->pin_display;
}

static inline void i915_gem_object_fence_lost(struct drm_i915_gem_object *obj)
{
	if (obj->tiling_mode)
		i915_gem_release_mmap(obj);

	/* As we do not have an associated fence register, we will force
	 * a tiling change if we ever need to acquire one.
	 */
	obj->fence_dirty = false;
	obj->fence_reg = I915_FENCE_REG_NONE;
}

/* some bookkeeping */
static void i915_gem_info_add_obj(struct drm_i915_private *dev_priv,
				  size_t size)
{
	spin_lock(&dev_priv->mm.object_stat_lock);
	dev_priv->mm.object_count++;
	dev_priv->mm.object_memory += size;
	spin_unlock(&dev_priv->mm.object_stat_lock);
}

static void i915_gem_info_remove_obj(struct drm_i915_private *dev_priv,
				     size_t size)
{
	spin_lock(&dev_priv->mm.object_stat_lock);
	dev_priv->mm.object_count--;
	dev_priv->mm.object_memory -= size;
	spin_unlock(&dev_priv->mm.object_stat_lock);
}

static int
i915_gem_wait_for_error(struct i915_gpu_error *error)
{
	int ret;

#define EXIT_COND (!i915_reset_in_progress(error) || \
		   i915_terminally_wedged(error))
	if (EXIT_COND)
		return 0;

	/*
	 * Only wait 10 seconds for the gpu reset to complete to avoid hanging
	 * userspace. If it takes that long something really bad is going on and
	 * we should simply try to bail out and fail as gracefully as possible.
	 */
	ret = wait_event_interruptible_timeout(error->reset_queue,
					       EXIT_COND,
					       10*HZ);
	if (ret == 0) {
		DRM_ERROR("Timed out waiting for the gpu reset to complete\n");
		return -EIO;
	} else if (ret < 0) {
		return ret;
	}
#undef EXIT_COND

	return 0;
}

int i915_mutex_lock_interruptible(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	ret = i915_gem_wait_for_error(&dev_priv->gpu_error);
	if (ret)
		return ret;

	ret = mutex_lock_interruptible(&dev->struct_mutex);
	if (ret)
		return ret;

	WARN_ON(i915_verify_lists(dev));
	return 0;
}

static inline bool
i915_gem_object_is_inactive(struct drm_i915_gem_object *obj)
{
	return i915_gem_obj_bound_any(obj) && !obj->active;
}

int
i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
			    struct drm_file *file)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_get_aperture *args = data;
	struct drm_i915_gem_object *obj;
	size_t pinned;

	pinned = 0;
	mutex_lock(&dev->struct_mutex);
	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list)
		if (i915_gem_obj_is_pinned(obj))
			pinned += i915_gem_obj_ggtt_size(obj);
	mutex_unlock(&dev->struct_mutex);

	args->aper_size = dev_priv->gtt.base.total;
	args->aper_available_size = args->aper_size - pinned;

	return 0;
}

static int
i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
{
	struct address_space *mapping = file_inode(obj->base.filp)->i_mapping;
	char *vaddr = obj->phys_handle->vaddr;
	struct sg_table *st;
	struct scatterlist *sg;
	int i;

	if (WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
		return -EINVAL;

	for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
		struct page *page;
		char *src;

		page = shmem_read_mapping_page(mapping, i);
		if (IS_ERR(page))
			return PTR_ERR(page);

		src = kmap_atomic(page);
		memcpy(vaddr, src, PAGE_SIZE);
		drm_clflush_virt_range(vaddr, PAGE_SIZE);
		kunmap_atomic(src);

		page_cache_release(page);
		vaddr += PAGE_SIZE;
	}

	i915_gem_chipset_flush(obj->base.dev);

	st = kmalloc(sizeof(*st), GFP_KERNEL);
	if (st == NULL)
		return -ENOMEM;

	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
		kfree(st);
		return -ENOMEM;
	}

	sg = st->sgl;
	sg->offset = 0;
	sg->length = obj->base.size;

	sg_dma_address(sg) = obj->phys_handle->busaddr;
	sg_dma_len(sg) = obj->base.size;

	obj->pages = st;
	obj->has_dma_mapping = true;
	return 0;
}

static void
i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj)
{
	int ret;

	BUG_ON(obj->madv == __I915_MADV_PURGED);

	ret = i915_gem_object_set_to_cpu_domain(obj, true);
	if (ret) {
		/* In the event of a disaster, abandon all caches and
		 * hope for the best.
		 */
		WARN_ON(ret != -EIO);
		obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
	}

	if (obj->madv == I915_MADV_DONTNEED)
		obj->dirty = 0;

	if (obj->dirty) {
		struct address_space *mapping = file_inode(obj->base.filp)->i_mapping;
		char *vaddr = obj->phys_handle->vaddr;
		int i;

		for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
			struct page *page;
			char *dst;

			page = shmem_read_mapping_page(mapping, i);
			if (IS_ERR(page))
				continue;

			dst = kmap_atomic(page);
			drm_clflush_virt_range(vaddr, PAGE_SIZE);
			memcpy(dst, vaddr, PAGE_SIZE);
			kunmap_atomic(dst);

			set_page_dirty(page);
			if (obj->madv == I915_MADV_WILLNEED)
				mark_page_accessed(page);
			page_cache_release(page);
			vaddr += PAGE_SIZE;
		}
		obj->dirty = 0;
	}

	sg_free_table(obj->pages);
	kfree(obj->pages);

	obj->has_dma_mapping = false;
}

static void
i915_gem_object_release_phys(struct drm_i915_gem_object *obj)
{
	drm_pci_free(obj->base.dev, obj->phys_handle);
}

static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
	.get_pages = i915_gem_object_get_pages_phys,
	.put_pages = i915_gem_object_put_pages_phys,
	.release = i915_gem_object_release_phys,
};

static int
drop_pages(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma, *next;
	int ret;

	drm_gem_object_reference(&obj->base);
	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link)
		if (i915_vma_unbind(vma))
			break;

	ret = i915_gem_object_put_pages(obj);
	drm_gem_object_unreference(&obj->base);

	return ret;
}

int
i915_gem_object_attach_phys(struct drm_i915_gem_object *obj,
			    int align)
{
	drm_dma_handle_t *phys;
	int ret;

	if (obj->phys_handle) {
		if ((unsigned long)obj->phys_handle->vaddr & (align -1))
			return -EBUSY;

		return 0;
	}

	if (obj->madv != I915_MADV_WILLNEED)
		return -EFAULT;

	if (obj->base.filp == NULL)
		return -EINVAL;

	ret = drop_pages(obj);
	if (ret)
		return ret;

	/* create a new object */
	phys = drm_pci_alloc(obj->base.dev, obj->base.size, align);
	if (!phys)
		return -ENOMEM;

	obj->phys_handle = phys;
	obj->ops = &i915_gem_phys_ops;

	return i915_gem_object_get_pages(obj);
}

static int
i915_gem_phys_pwrite(struct drm_i915_gem_object *obj,
		     struct drm_i915_gem_pwrite *args,
		     struct drm_file *file_priv)
{
	struct drm_device *dev = obj->base.dev;
	void *vaddr = obj->phys_handle->vaddr + args->offset;
	char __user *user_data = to_user_ptr(args->data_ptr);
	int ret;

	/* We manually control the domain here and pretend that it
	 * remains coherent i.e. in the GTT domain, like shmem_pwrite.
	 */
	ret = i915_gem_object_wait_rendering(obj, false);
	if (ret)
		return ret;

	if (__copy_from_user_inatomic_nocache(vaddr, user_data, args->size)) {
		unsigned long unwritten;

		/* The physical object once assigned is fixed for the lifetime
		 * of the obj, so we can safely drop the lock and continue
		 * to access vaddr.
		 */
		mutex_unlock(&dev->struct_mutex);
		unwritten = copy_from_user(vaddr, user_data, args->size);
		mutex_lock(&dev->struct_mutex);
		if (unwritten)
			return -EFAULT;
	}

	drm_clflush_virt_range(vaddr, args->size);
	i915_gem_chipset_flush(dev);
	return 0;
}

void *i915_gem_object_alloc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	return kmem_cache_zalloc(dev_priv->slab, GFP_KERNEL);
}

void i915_gem_object_free(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	kmem_cache_free(dev_priv->slab, obj);
}

static int
i915_gem_create(struct drm_file *file,
		struct drm_device *dev,
		uint64_t size,
		uint32_t *handle_p)
{
	struct drm_i915_gem_object *obj;
	int ret;
	u32 handle;

	size = roundup(size, PAGE_SIZE);
	if (size == 0)
		return -EINVAL;

	/* Allocate the new object */
	obj = i915_gem_alloc_object(dev, size);
	if (obj == NULL)
		return -ENOMEM;

	ret = drm_gem_handle_create(file, &obj->base, &handle);
	/* drop reference from allocate - handle holds it now */
	drm_gem_object_unreference_unlocked(&obj->base);
	if (ret)
		return ret;

	*handle_p = handle;
	return 0;
}

int
i915_gem_dumb_create(struct drm_file *file,
		     struct drm_device *dev,
		     struct drm_mode_create_dumb *args)
{
	/* have to work out size/pitch and return them */
	args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64);
	args->size = args->pitch * args->height;
	return i915_gem_create(file, dev,
			       args->size, &args->handle);
}

/**
 * Creates a new mm object and returns a handle to it.
 */
int
i915_gem_create_ioctl(struct drm_device *dev, void *data,
		      struct drm_file *file)
{
	struct drm_i915_gem_create *args = data;

	return i915_gem_create(file, dev,
			       args->size, &args->handle);
}

static inline int
__copy_to_user_swizzled(char __user *cpu_vaddr,
			const char *gpu_vaddr, int gpu_offset,
			int length)
{
	int ret, cpu_offset = 0;

	while (length > 0) {
		int cacheline_end = ALIGN(gpu_offset + 1, 64);
		int this_length = min(cacheline_end - gpu_offset, length);
		int swizzled_gpu_offset = gpu_offset ^ 64;

		ret = __copy_to_user(cpu_vaddr + cpu_offset,
				     gpu_vaddr + swizzled_gpu_offset,
				     this_length);
		if (ret)
			return ret + length;

		cpu_offset += this_length;
		gpu_offset += this_length;
		length -= this_length;
	}

	return 0;
}

static inline int
__copy_from_user_swizzled(char *gpu_vaddr, int gpu_offset,
			  const char __user *cpu_vaddr,
			  int length)
{
	int ret, cpu_offset = 0;

	while (length > 0) {
		int cacheline_end = ALIGN(gpu_offset + 1, 64);
		int this_length = min(cacheline_end - gpu_offset, length);
		int swizzled_gpu_offset = gpu_offset ^ 64;

		ret = __copy_from_user(gpu_vaddr + swizzled_gpu_offset,
				       cpu_vaddr + cpu_offset,
				       this_length);
		if (ret)
			return ret + length;

		cpu_offset += this_length;
		gpu_offset += this_length;
		length -= this_length;
	}

	return 0;
}

/*
 * Pins the specified object's pages and synchronizes the object with
 * GPU accesses. Sets needs_clflush to non-zero if the caller should
 * flush the object from the CPU cache.
 */
int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj,
				    int *needs_clflush)
{
	int ret;

	*needs_clflush = 0;

	if (!obj->base.filp)
		return -EINVAL;

	if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) {
		/* If we're not in the cpu read domain, set ourself into the gtt
		 * read domain and manually flush cachelines (if required). This
		 * optimizes for the case when the gpu will dirty the data
		 * anyway again before the next pread happens. */
		*needs_clflush = !cpu_cache_is_coherent(obj->base.dev,
							obj->cache_level);
		ret = i915_gem_object_wait_rendering(obj, true);
		if (ret)
			return ret;

		i915_gem_object_retire(obj);
	}

	ret = i915_gem_object_get_pages(obj);
	if (ret)
		return ret;

	i915_gem_object_pin_pages(obj);

	return ret;
}

/* Per-page copy function for the shmem pread fastpath.
 * Flushes invalid cachelines before reading the target if
 * needs_clflush is set. */
static int
shmem_pread_fast(struct page *page, int shmem_page_offset, int page_length,
		 char __user *user_data,
		 bool page_do_bit17_swizzling, bool needs_clflush)
{
	char *vaddr;
	int ret;

	if (unlikely(page_do_bit17_swizzling))
		return -EINVAL;

	vaddr = kmap_atomic(page);
	if (needs_clflush)
		drm_clflush_virt_range(vaddr + shmem_page_offset,
				       page_length);
	ret = __copy_to_user_inatomic(user_data,
				      vaddr + shmem_page_offset,
				      page_length);
	kunmap_atomic(vaddr);

	return ret ? -EFAULT : 0;
}

static void
shmem_clflush_swizzled_range(char *addr, unsigned long length,
			     bool swizzled)
{
	if (unlikely(swizzled)) {
		unsigned long start = (unsigned long) addr;
		unsigned long end = (unsigned long) addr + length;

		/* For swizzling simply ensure that we always flush both
		 * channels. Lame, but simple and it works. Swizzled
		 * pwrite/pread is far from a hotpath - current userspace
		 * doesn't use it at all. */
		start = round_down(start, 128);
		end = round_up(end, 128);

		drm_clflush_virt_range((void *)start, end - start);
	} else {
		drm_clflush_virt_range(addr, length);
	}

}

/* Only difference to the fast-path function is that this can handle bit17
 * and uses non-atomic copy and kmap functions. */
static int
shmem_pread_slow(struct page *page, int shmem_page_offset, int page_length,
		 char __user *user_data,
		 bool page_do_bit17_swizzling, bool needs_clflush)
{
	char *vaddr;
	int ret;

	vaddr = kmap(page);
	if (needs_clflush)
		shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
					     page_length,
					     page_do_bit17_swizzling);

	if (page_do_bit17_swizzling)
		ret = __copy_to_user_swizzled(user_data,
					      vaddr, shmem_page_offset,
					      page_length);
	else
		ret = __copy_to_user(user_data,
				     vaddr + shmem_page_offset,
				     page_length);
	kunmap(page);

	return ret ? - EFAULT : 0;
}

static int
i915_gem_shmem_pread(struct drm_device *dev,
		     struct drm_i915_gem_object *obj,
		     struct drm_i915_gem_pread *args,
		     struct drm_file *file)
{
	char __user *user_data;
	ssize_t remain;
	loff_t offset;
	int shmem_page_offset, page_length, ret = 0;
	int obj_do_bit17_swizzling, page_do_bit17_swizzling;
	int prefaulted = 0;
	int needs_clflush = 0;
	struct sg_page_iter sg_iter;

	user_data = to_user_ptr(args->data_ptr);
	remain = args->size;

	obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);

	ret = i915_gem_obj_prepare_shmem_read(obj, &needs_clflush);
	if (ret)
		return ret;

	offset = args->offset;

	for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
			 offset >> PAGE_SHIFT) {
		struct page *page = sg_page_iter_page(&sg_iter);

		if (remain <= 0)
			break;

		/* Operation in this page
		 *
		 * shmem_page_offset = offset within page in shmem file
		 * page_length = bytes to copy for this page
		 */
		shmem_page_offset = offset_in_page(offset);
		page_length = remain;
		if ((shmem_page_offset + page_length) > PAGE_SIZE)
			page_length = PAGE_SIZE - shmem_page_offset;

		page_do_bit17_swizzling = obj_do_bit17_swizzling &&
			(page_to_phys(page) & (1 << 17)) != 0;

		ret = shmem_pread_fast(page, shmem_page_offset, page_length,
				       user_data, page_do_bit17_swizzling,
				       needs_clflush);
		if (ret == 0)
			goto next_page;

		mutex_unlock(&dev->struct_mutex);

		if (likely(!i915.prefault_disable) && !prefaulted) {
			ret = fault_in_multipages_writeable(user_data, remain);
			/* Userspace is tricking us, but we've already clobbered
			 * its pages with the prefault and promised to write the
			 * data up to the first fault. Hence ignore any errors
			 * and just continue. */
			(void)ret;
			prefaulted = 1;
		}

		ret = shmem_pread_slow(page, shmem_page_offset, page_length,
				       user_data, page_do_bit17_swizzling,
				       needs_clflush);

		mutex_lock(&dev->struct_mutex);

		if (ret)
			goto out;

next_page:
		remain -= page_length;
		user_data += page_length;
		offset += page_length;
	}

out:
	i915_gem_object_unpin_pages(obj);

	return ret;
}

/**
 * Reads data from the object referenced by handle.
 *
 * On error, the contents of *data are undefined.
 */
int
i915_gem_pread_ioctl(struct drm_device *dev, void *data,
		     struct drm_file *file)
{
	struct drm_i915_gem_pread *args = data;
	struct drm_i915_gem_object *obj;
	int ret = 0;

	if (args->size == 0)
		return 0;

	if (!access_ok(VERIFY_WRITE,
		       to_user_ptr(args->data_ptr),
		       args->size))
		return -EFAULT;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	/* Bounds check source.  */
	if (args->offset > obj->base.size ||
	    args->size > obj->base.size - args->offset) {
		ret = -EINVAL;
		goto out;
	}

	/* prime objects have no backing filp to GEM pread/pwrite
	 * pages from.
	 */
	if (!obj->base.filp) {
		ret = -EINVAL;
		goto out;
	}

	trace_i915_gem_object_pread(obj, args->offset, args->size);

	ret = i915_gem_shmem_pread(dev, obj, args, file);

out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/* This is the fast write path which cannot handle
 * page faults in the source data
 */

static inline int
fast_user_write(struct io_mapping *mapping,
		loff_t page_base, int page_offset,
		char __user *user_data,
		int length)
{
	void __iomem *vaddr_atomic;
	void *vaddr;
	unsigned long unwritten;

	vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
	/* We can use the cpu mem copy function because this is X86. */
	vaddr = (void __force*)vaddr_atomic + page_offset;
	unwritten = __copy_from_user_inatomic_nocache(vaddr,
						      user_data, length);
	io_mapping_unmap_atomic(vaddr_atomic);
	return unwritten;
}

/**
 * This is the fast pwrite path, where we copy the data directly from the
 * user into the GTT, uncached.
 */
static int
i915_gem_gtt_pwrite_fast(struct drm_device *dev,
			 struct drm_i915_gem_object *obj,
			 struct drm_i915_gem_pwrite *args,
			 struct drm_file *file)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	ssize_t remain;
	loff_t offset, page_base;
	char __user *user_data;
	int page_offset, page_length, ret;

	ret = i915_gem_obj_ggtt_pin(obj, 0, PIN_MAPPABLE | PIN_NONBLOCK);
	if (ret)
		goto out;

	ret = i915_gem_object_set_to_gtt_domain(obj, true);
	if (ret)
		goto out_unpin;

	ret = i915_gem_object_put_fence(obj);
	if (ret)
		goto out_unpin;

	user_data = to_user_ptr(args->data_ptr);
	remain = args->size;

	offset = i915_gem_obj_ggtt_offset(obj) + args->offset;

	while (remain > 0) {
		/* Operation in this page
		 *
		 * page_base = page offset within aperture
		 * page_offset = offset within page
		 * page_length = bytes to copy for this page
		 */
		page_base = offset & PAGE_MASK;
		page_offset = offset_in_page(offset);
		page_length = remain;
		if ((page_offset + remain) > PAGE_SIZE)
			page_length = PAGE_SIZE - page_offset;

		/* If we get a fault while copying data, then (presumably) our
		 * source page isn't available.  Return the error and we'll
		 * retry in the slow path.
		 */
		if (fast_user_write(dev_priv->gtt.mappable, page_base,
				    page_offset, user_data, page_length)) {
			ret = -EFAULT;
			goto out_unpin;
		}

		remain -= page_length;
		user_data += page_length;
		offset += page_length;
	}

out_unpin:
	i915_gem_object_ggtt_unpin(obj);
out:
	return ret;
}

/* Per-page copy function for the shmem pwrite fastpath.
 * Flushes invalid cachelines before writing to the target if
 * needs_clflush_before is set and flushes out any written cachelines after
 * writing if needs_clflush is set. */
static int
shmem_pwrite_fast(struct page *page, int shmem_page_offset, int page_length,
		  char __user *user_data,
		  bool page_do_bit17_swizzling,
		  bool needs_clflush_before,
		  bool needs_clflush_after)
{
	char *vaddr;
	int ret;

	if (unlikely(page_do_bit17_swizzling))
		return -EINVAL;

	vaddr = kmap_atomic(page);
	if (needs_clflush_before)
		drm_clflush_virt_range(vaddr + shmem_page_offset,
				       page_length);
	ret = __copy_from_user_inatomic(vaddr + shmem_page_offset,
					user_data, page_length);
	if (needs_clflush_after)
		drm_clflush_virt_range(vaddr + shmem_page_offset,
				       page_length);
	kunmap_atomic(vaddr);

	return ret ? -EFAULT : 0;
}

/* Only difference to the fast-path function is that this can handle bit17
 * and uses non-atomic copy and kmap functions. */
static int
shmem_pwrite_slow(struct page *page, int shmem_page_offset, int page_length,
		  char __user *user_data,
		  bool page_do_bit17_swizzling,
		  bool needs_clflush_before,
		  bool needs_clflush_after)
{
	char *vaddr;
	int ret;

	vaddr = kmap(page);
	if (unlikely(needs_clflush_before || page_do_bit17_swizzling))
		shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
					     page_length,
					     page_do_bit17_swizzling);
	if (page_do_bit17_swizzling)
		ret = __copy_from_user_swizzled(vaddr, shmem_page_offset,
						user_data,
						page_length);
	else
		ret = __copy_from_user(vaddr + shmem_page_offset,
				       user_data,
				       page_length);
	if (needs_clflush_after)
		shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
					     page_length,
					     page_do_bit17_swizzling);
	kunmap(page);

	return ret ? -EFAULT : 0;
}

static int
i915_gem_shmem_pwrite(struct drm_device *dev,
		      struct drm_i915_gem_object *obj,
		      struct drm_i915_gem_pwrite *args,
		      struct drm_file *file)
{
	ssize_t remain;
	loff_t offset;
	char __user *user_data;
	int shmem_page_offset, page_length, ret = 0;
	int obj_do_bit17_swizzling, page_do_bit17_swizzling;
	int hit_slowpath = 0;
	int needs_clflush_after = 0;
	int needs_clflush_before = 0;
	struct sg_page_iter sg_iter;

	user_data = to_user_ptr(args->data_ptr);
	remain = args->size;

	obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);

	if (obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
		/* If we're not in the cpu write domain, set ourself into the gtt
		 * write domain and manually flush cachelines (if required). This
		 * optimizes for the case when the gpu will use the data
		 * right away and we therefore have to clflush anyway. */
		needs_clflush_after = cpu_write_needs_clflush(obj);
		ret = i915_gem_object_wait_rendering(obj, false);
		if (ret)
			return ret;

		i915_gem_object_retire(obj);
	}
	/* Same trick applies to invalidate partially written cachelines read
	 * before writing. */
	if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0)
		needs_clflush_before =
			!cpu_cache_is_coherent(dev, obj->cache_level);

	ret = i915_gem_object_get_pages(obj);
	if (ret)
		return ret;

	i915_gem_object_pin_pages(obj);

	offset = args->offset;
	obj->dirty = 1;

	for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
			 offset >> PAGE_SHIFT) {
		struct page *page = sg_page_iter_page(&sg_iter);
		int partial_cacheline_write;

		if (remain <= 0)
			break;

		/* Operation in this page
		 *
		 * shmem_page_offset = offset within page in shmem file
		 * page_length = bytes to copy for this page
		 */
		shmem_page_offset = offset_in_page(offset);

		page_length = remain;
		if ((shmem_page_offset + page_length) > PAGE_SIZE)
			page_length = PAGE_SIZE - shmem_page_offset;

		/* If we don't overwrite a cacheline completely we need to be
		 * careful to have up-to-date data by first clflushing. Don't
		 * overcomplicate things and flush the entire patch. */
		partial_cacheline_write = needs_clflush_before &&
			((shmem_page_offset | page_length)
				& (boot_cpu_data.x86_clflush_size - 1));

		page_do_bit17_swizzling = obj_do_bit17_swizzling &&
			(page_to_phys(page) & (1 << 17)) != 0;

		ret = shmem_pwrite_fast(page, shmem_page_offset, page_length,
					user_data, page_do_bit17_swizzling,
					partial_cacheline_write,
					needs_clflush_after);
		if (ret == 0)
			goto next_page;

		hit_slowpath = 1;
		mutex_unlock(&dev->struct_mutex);
		ret = shmem_pwrite_slow(page, shmem_page_offset, page_length,
					user_data, page_do_bit17_swizzling,
					partial_cacheline_write,
					needs_clflush_after);

		mutex_lock(&dev->struct_mutex);

		if (ret)
			goto out;

next_page:
		remain -= page_length;
		user_data += page_length;
		offset += page_length;
	}

out:
	i915_gem_object_unpin_pages(obj);

	if (hit_slowpath) {
		/*
		 * Fixup: Flush cpu caches in case we didn't flush the dirty
		 * cachelines in-line while writing and the object moved
		 * out of the cpu write domain while we've dropped the lock.
		 */
		if (!needs_clflush_after &&
		    obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
			if (i915_gem_clflush_object(obj, obj->pin_display))
				i915_gem_chipset_flush(dev);
		}
	}

	if (needs_clflush_after)
		i915_gem_chipset_flush(dev);

	return ret;
}

/**
 * Writes data to the object referenced by handle.
 *
 * On error, the contents of the buffer that were to be modified are undefined.
 */
int
i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
		      struct drm_file *file)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_pwrite *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	if (args->size == 0)
		return 0;

	if (!access_ok(VERIFY_READ,
		       to_user_ptr(args->data_ptr),
		       args->size))
		return -EFAULT;

	if (likely(!i915.prefault_disable)) {
		ret = fault_in_multipages_readable(to_user_ptr(args->data_ptr),
						   args->size);
		if (ret)
			return -EFAULT;
	}

	intel_runtime_pm_get(dev_priv);

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		goto put_rpm;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	/* Bounds check destination. */
	if (args->offset > obj->base.size ||
	    args->size > obj->base.size - args->offset) {
		ret = -EINVAL;
		goto out;
	}

	/* prime objects have no backing filp to GEM pread/pwrite
	 * pages from.
	 */
	if (!obj->base.filp) {
		ret = -EINVAL;
		goto out;
	}

	trace_i915_gem_object_pwrite(obj, args->offset, args->size);

	ret = -EFAULT;
	/* We can only do the GTT pwrite on untiled buffers, as otherwise
	 * it would end up going through the fenced access, and we'll get
	 * different detiling behavior between reading and writing.
	 * pread/pwrite currently are reading and writing from the CPU
	 * perspective, requiring manual detiling by the client.
	 */
	if (obj->tiling_mode == I915_TILING_NONE &&
	    obj->base.write_domain != I915_GEM_DOMAIN_CPU &&
	    cpu_write_needs_clflush(obj)) {
		ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file);
		/* Note that the gtt paths might fail with non-page-backed user
		 * pointers (e.g. gtt mappings when moving data between
		 * textures). Fallback to the shmem path in that case. */
	}

	if (ret == -EFAULT || ret == -ENOSPC) {
		if (obj->phys_handle)
			ret = i915_gem_phys_pwrite(obj, args, file);
		else
			ret = i915_gem_shmem_pwrite(dev, obj, args, file);
	}

out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
put_rpm:
	intel_runtime_pm_put(dev_priv);

	return ret;
}

int
i915_gem_check_wedge(struct i915_gpu_error *error,
		     bool interruptible)
{
	if (i915_reset_in_progress(error)) {
		/* Non-interruptible callers can't handle -EAGAIN, hence return
		 * -EIO unconditionally for these. */
		if (!interruptible)
			return -EIO;

		/* Recovery complete, but the reset failed ... */
		if (i915_terminally_wedged(error))
			return -EIO;

		/*
		 * Check if GPU Reset is in progress - we need intel_ring_begin
		 * to work properly to reinit the hw state while the gpu is
		 * still marked as reset-in-progress. Handle this with a flag.
		 */
		if (!error->reload_in_reset)
			return -EAGAIN;
	}

	return 0;
}

/*
 * Compare seqno against outstanding lazy request. Emit a request if they are
 * equal.
 */
int
i915_gem_check_olr(struct intel_engine_cs *ring, u32 seqno)
{
	int ret;

	BUG_ON(!mutex_is_locked(&ring->dev->struct_mutex));

	ret = 0;
	if (seqno == ring->outstanding_lazy_seqno)
		ret = i915_add_request(ring, NULL);

	return ret;
}

static void fake_irq(unsigned long data)
{
	wake_up_process((struct task_struct *)data);
}

static bool missed_irq(struct drm_i915_private *dev_priv,
		       struct intel_engine_cs *ring)
{
	return test_bit(ring->id, &dev_priv->gpu_error.missed_irq_rings);
}

static bool can_wait_boost(struct drm_i915_file_private *file_priv)
{
	if (file_priv == NULL)
		return true;

	return !atomic_xchg(&file_priv->rps_wait_boost, true);
}

/**
 * __i915_wait_seqno - wait until execution of seqno has finished
 * @ring: the ring expected to report seqno
 * @seqno: duh!
 * @reset_counter: reset sequence associated with the given seqno
 * @interruptible: do an interruptible wait (normally yes)
 * @timeout: in - how long to wait (NULL forever); out - how much time remaining
 *
 * Note: It is of utmost importance that the passed in seqno and reset_counter
 * values have been read by the caller in an smp safe manner. Where read-side
 * locks are involved, it is sufficient to read the reset_counter before
 * unlocking the lock that protects the seqno. For lockless tricks, the
 * reset_counter _must_ be read before, and an appropriate smp_rmb must be
 * inserted.
 *
 * Returns 0 if the seqno was found within the alloted time. Else returns the
 * errno with remaining time filled in timeout argument.
 */
int __i915_wait_seqno(struct intel_engine_cs *ring, u32 seqno,
			unsigned reset_counter,
			bool interruptible,
			s64 *timeout,
			struct drm_i915_file_private *file_priv)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	const bool irq_test_in_progress =
		ACCESS_ONCE(dev_priv->gpu_error.test_irq_rings) & intel_ring_flag(ring);
	DEFINE_WAIT(wait);
	unsigned long timeout_expire;
	s64 before, now;
	int ret;

	WARN(!intel_irqs_enabled(dev_priv), "IRQs disabled");

	if (i915_seqno_passed(ring->get_seqno(ring, true), seqno))
		return 0;

	timeout_expire = timeout ?
		jiffies + nsecs_to_jiffies_timeout((u64)*timeout) : 0;

	if (INTEL_INFO(dev)->gen >= 6 && ring->id == RCS && can_wait_boost(file_priv)) {
		gen6_rps_boost(dev_priv);
		if (file_priv)
			mod_delayed_work(dev_priv->wq,
					 &file_priv->mm.idle_work,
					 msecs_to_jiffies(100));
	}

	if (!irq_test_in_progress && WARN_ON(!ring->irq_get(ring)))
		return -ENODEV;

	/* Record current time in case interrupted by signal, or wedged */
	trace_i915_gem_request_wait_begin(ring, seqno);
	before = ktime_get_raw_ns();
	for (;;) {
		struct timer_list timer;

		prepare_to_wait(&ring->irq_queue, &wait,
				interruptible ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);

		/* We need to check whether any gpu reset happened in between
		 * the caller grabbing the seqno and now ... */
		if (reset_counter != atomic_read(&dev_priv->gpu_error.reset_counter)) {
			/* ... but upgrade the -EAGAIN to an -EIO if the gpu
			 * is truely gone. */
			ret = i915_gem_check_wedge(&dev_priv->gpu_error, interruptible);
			if (ret == 0)
				ret = -EAGAIN;
			break;
		}

		if (i915_seqno_passed(ring->get_seqno(ring, false), seqno)) {
			ret = 0;
			break;
		}

		if (interruptible && signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}

		if (timeout && time_after_eq(jiffies, timeout_expire)) {
			ret = -ETIME;
			break;
		}

		timer.function = NULL;
		if (timeout || missed_irq(dev_priv, ring)) {
			unsigned long expire;

			setup_timer_on_stack(&timer, fake_irq, (unsigned long)current);
			expire = missed_irq(dev_priv, ring) ? jiffies + 1 : timeout_expire;
			mod_timer(&timer, expire);
		}

		io_schedule();

		if (timer.function) {
			del_singleshot_timer_sync(&timer);
			destroy_timer_on_stack(&timer);
		}
	}
	now = ktime_get_raw_ns();
	trace_i915_gem_request_wait_end(ring, seqno);

	if (!irq_test_in_progress)
		ring->irq_put(ring);

	finish_wait(&ring->irq_queue, &wait);

	if (timeout) {
		s64 tres = *timeout - (now - before);

		*timeout = tres < 0 ? 0 : tres;

		/*
		 * Apparently ktime isn't accurate enough and occasionally has a
		 * bit of mismatch in the jiffies<->nsecs<->ktime loop. So patch
		 * things up to make the test happy. We allow up to 1 jiffy.
		 *
		 * This is a regrssion from the timespec->ktime conversion.
		 */
		if (ret == -ETIME && *timeout < jiffies_to_usecs(1)*1000)
			*timeout = 0;
	}

	return ret;
}

/**
 * Waits for a sequence number to be signaled, and cleans up the
 * request and object lists appropriately for that event.
 */
int
i915_wait_seqno(struct intel_engine_cs *ring, uint32_t seqno)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	bool interruptible = dev_priv->mm.interruptible;
	unsigned reset_counter;
	int ret;

	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
	BUG_ON(seqno == 0);

	ret = i915_gem_check_wedge(&dev_priv->gpu_error, interruptible);
	if (ret)
		return ret;

	ret = i915_gem_check_olr(ring, seqno);
	if (ret)
		return ret;

	reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter);
	return __i915_wait_seqno(ring, seqno, reset_counter, interruptible,
				 NULL, NULL);
}

static int
i915_gem_object_wait_rendering__tail(struct drm_i915_gem_object *obj)
{
	if (!obj->active)
		return 0;

	/* Manually manage the write flush as we may have not yet
	 * retired the buffer.
	 *
	 * Note that the last_write_seqno is always the earlier of
	 * the two (read/write) seqno, so if we haved successfully waited,
	 * we know we have passed the last write.
	 */
	obj->last_write_seqno = 0;

	return 0;
}

/**
 * Ensures that all rendering to the object has completed and the object is
 * safe to unbind from the GTT or access from the CPU.
 */
static __must_check int
i915_gem_object_wait_rendering(struct drm_i915_gem_object *obj,
			       bool readonly)
{
	struct intel_engine_cs *ring = obj->ring;
	u32 seqno;
	int ret;

	seqno = readonly ? obj->last_write_seqno : obj->last_read_seqno;
	if (seqno == 0)
		return 0;

	ret = i915_wait_seqno(ring, seqno);
	if (ret)
		return ret;

	return i915_gem_object_wait_rendering__tail(obj);
}

/* A nonblocking variant of the above wait. This is a highly dangerous routine
 * as the object state may change during this call.
 */
static __must_check int
i915_gem_object_wait_rendering__nonblocking(struct drm_i915_gem_object *obj,
					    struct drm_i915_file_private *file_priv,
					    bool readonly)
{
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = obj->ring;
	unsigned reset_counter;
	u32 seqno;
	int ret;

	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
	BUG_ON(!dev_priv->mm.interruptible);

	seqno = readonly ? obj->last_write_seqno : obj->last_read_seqno;
	if (seqno == 0)
		return 0;

	ret = i915_gem_check_wedge(&dev_priv->gpu_error, true);
	if (ret)
		return ret;

	ret = i915_gem_check_olr(ring, seqno);
	if (ret)
		return ret;

	reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter);
	mutex_unlock(&dev->struct_mutex);
	ret = __i915_wait_seqno(ring, seqno, reset_counter, true, NULL,
				file_priv);
	mutex_lock(&dev->struct_mutex);
	if (ret)
		return ret;

	return i915_gem_object_wait_rendering__tail(obj);
}

/**
 * Called when user space prepares to use an object with the CPU, either
 * through the mmap ioctl's mapping or a GTT mapping.
 */
int
i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
			  struct drm_file *file)
{
	struct drm_i915_gem_set_domain *args = data;
	struct drm_i915_gem_object *obj;
	uint32_t read_domains = args->read_domains;
	uint32_t write_domain = args->write_domain;
	int ret;

	/* Only handle setting domains to types used by the CPU. */
	if (write_domain & I915_GEM_GPU_DOMAINS)
		return -EINVAL;

	if (read_domains & I915_GEM_GPU_DOMAINS)
		return -EINVAL;

	/* Having something in the write domain implies it's in the read
	 * domain, and only that read domain.  Enforce that in the request.
	 */
	if (write_domain != 0 && read_domains != write_domain)
		return -EINVAL;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	/* Try to flush the object off the GPU without holding the lock.
	 * We will repeat the flush holding the lock in the normal manner
	 * to catch cases where we are gazumped.
	 */
	ret = i915_gem_object_wait_rendering__nonblocking(obj,
							  file->driver_priv,
							  !write_domain);
	if (ret)
		goto unref;

	if (read_domains & I915_GEM_DOMAIN_GTT) {
		ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0);

		/* Silently promote "you're not bound, there was nothing to do"
		 * to success, since the client was just asking us to
		 * make sure everything was done.
		 */
		if (ret == -EINVAL)
			ret = 0;
	} else {
		ret = i915_gem_object_set_to_cpu_domain(obj, write_domain != 0);
	}

unref:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * Called when user space has done writes to this buffer
 */
int
i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
			 struct drm_file *file)
{
	struct drm_i915_gem_sw_finish *args = data;
	struct drm_i915_gem_object *obj;
	int ret = 0;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	/* Pinned buffers may be scanout, so flush the cache */
	if (obj->pin_display)
		i915_gem_object_flush_cpu_write_domain(obj, true);

	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * Maps the contents of an object, returning the address it is mapped
 * into.
 *
 * While the mapping holds a reference on the contents of the object, it doesn't
 * imply a ref on the object itself.
 *
 * IMPORTANT:
 *
 * DRM driver writers who look a this function as an example for how to do GEM
 * mmap support, please don't implement mmap support like here. The modern way
 * to implement DRM mmap support is with an mmap offset ioctl (like
 * i915_gem_mmap_gtt) and then using the mmap syscall on the DRM fd directly.
 * That way debug tooling like valgrind will understand what's going on, hiding
 * the mmap call in a driver private ioctl will break that. The i915 driver only
 * does cpu mmaps this way because we didn't know better.
 */
int
i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
		    struct drm_file *file)
{
	struct drm_i915_gem_mmap *args = data;
	struct drm_gem_object *obj;
	unsigned long addr;

	obj = drm_gem_object_lookup(dev, file, args->handle);
	if (obj == NULL)
		return -ENOENT;

	/* prime objects have no backing filp to GEM mmap
	 * pages from.
	 */
	if (!obj->filp) {
		drm_gem_object_unreference_unlocked(obj);
		return -EINVAL;
	}

	addr = vm_mmap(obj->filp, 0, args->size,
		       PROT_READ | PROT_WRITE, MAP_SHARED,
		       args->offset);
	drm_gem_object_unreference_unlocked(obj);
	if (IS_ERR((void *)addr))
		return addr;

	args->addr_ptr = (uint64_t) addr;

	return 0;
}

/**
 * i915_gem_fault - fault a page into the GTT
 * vma: VMA in question
 * vmf: fault info
 *
 * The fault handler is set up by drm_gem_mmap() when a object is GTT mapped
 * from userspace.  The fault handler takes care of binding the object to
 * the GTT (if needed), allocating and programming a fence register (again,
 * only if needed based on whether the old reg is still valid or the object
 * is tiled) and inserting a new PTE into the faulting process.
 *
 * Note that the faulting process may involve evicting existing objects
 * from the GTT and/or fence registers to make room.  So performance may
 * suffer if the GTT working set is large or there are few fence registers
 * left.
 */
int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct drm_i915_gem_object *obj = to_intel_bo(vma->vm_private_data);
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	pgoff_t page_offset;
	unsigned long pfn;
	int ret = 0;
	bool write = !!(vmf->flags & FAULT_FLAG_WRITE);

	intel_runtime_pm_get(dev_priv);

	/* We don't use vmf->pgoff since that has the fake offset */
	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
		PAGE_SHIFT;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		goto out;

	trace_i915_gem_object_fault(obj, page_offset, true, write);

	/* Try to flush the object off the GPU first without holding the lock.
	 * Upon reacquiring the lock, we will perform our sanity checks and then
	 * repeat the flush holding the lock in the normal manner to catch cases
	 * where we are gazumped.
	 */
	ret = i915_gem_object_wait_rendering__nonblocking(obj, NULL, !write);
	if (ret)
		goto unlock;

	/* Access to snoopable pages through the GTT is incoherent. */
	if (obj->cache_level != I915_CACHE_NONE && !HAS_LLC(dev)) {
		ret = -EFAULT;
		goto unlock;
	}

	/* Now bind it into the GTT if needed */
	ret = i915_gem_obj_ggtt_pin(obj, 0, PIN_MAPPABLE);
	if (ret)
		goto unlock;

	ret = i915_gem_object_set_to_gtt_domain(obj, write);
	if (ret)
		goto unpin;

	ret = i915_gem_object_get_fence(obj);
	if (ret)
		goto unpin;

	/* Finally, remap it using the new GTT offset */
	pfn = dev_priv->gtt.mappable_base + i915_gem_obj_ggtt_offset(obj);
	pfn >>= PAGE_SHIFT;

	if (!obj->fault_mappable) {
		unsigned long size = min_t(unsigned long,
					   vma->vm_end - vma->vm_start,
					   obj->base.size);
		int i;

		for (i = 0; i < size >> PAGE_SHIFT; i++) {
			ret = vm_insert_pfn(vma,
					    (unsigned long)vma->vm_start + i * PAGE_SIZE,
					    pfn + i);
			if (ret)
				break;
		}

		obj->fault_mappable = true;
	} else
		ret = vm_insert_pfn(vma,
				    (unsigned long)vmf->virtual_address,
				    pfn + page_offset);
unpin:
	i915_gem_object_ggtt_unpin(obj);
unlock:
	mutex_unlock(&dev->struct_mutex);
out:
	switch (ret) {
	case -EIO:
		/*
		 * We eat errors when the gpu is terminally wedged to avoid
		 * userspace unduly crashing (gl has no provisions for mmaps to
		 * fail). But any other -EIO isn't ours (e.g. swap in failure)
		 * and so needs to be reported.
		 */
		if (!i915_terminally_wedged(&dev_priv->gpu_error)) {
			ret = VM_FAULT_SIGBUS;
			break;
		}
	case -EAGAIN:
		/*
		 * EAGAIN means the gpu is hung and we'll wait for the error
		 * handler to reset everything when re-faulting in
		 * i915_mutex_lock_interruptible.
		 */
	case 0:
	case -ERESTARTSYS:
	case -EINTR:
	case -EBUSY:
		/*
		 * EBUSY is ok: this just means that another thread
		 * already did the job.
		 */
		ret = VM_FAULT_NOPAGE;
		break;
	case -ENOMEM:
		ret = VM_FAULT_OOM;
		break;
	case -ENOSPC:
	case -EFAULT:
		ret = VM_FAULT_SIGBUS;
		break;
	default:
		WARN_ONCE(ret, "unhandled error in i915_gem_fault: %i\n", ret);
		ret = VM_FAULT_SIGBUS;
		break;
	}

	intel_runtime_pm_put(dev_priv);
	return ret;
}

/**
 * i915_gem_release_mmap - remove physical page mappings
 * @obj: obj in question
 *
 * Preserve the reservation of the mmapping with the DRM core code, but
 * relinquish ownership of the pages back to the system.
 *
 * It is vital that we remove the page mapping if we have mapped a tiled
 * object through the GTT and then lose the fence register due to
 * resource pressure. Similarly if the object has been moved out of the
 * aperture, than pages mapped into userspace must be revoked. Removing the
 * mapping will then trigger a page fault on the next user access, allowing
 * fixup by i915_gem_fault().
 */
void
i915_gem_release_mmap(struct drm_i915_gem_object *obj)
{
	if (!obj->fault_mappable)
		return;

	drm_vma_node_unmap(&obj->base.vma_node,
			   obj->base.dev->anon_inode->i_mapping);
	obj->fault_mappable = false;
}

void
i915_gem_release_all_mmaps(struct drm_i915_private *dev_priv)
{
	struct drm_i915_gem_object *obj;

	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list)
		i915_gem_release_mmap(obj);
}

uint32_t
i915_gem_get_gtt_size(struct drm_device *dev, uint32_t size, int tiling_mode)
{
	uint32_t gtt_size;

	if (INTEL_INFO(dev)->gen >= 4 ||
	    tiling_mode == I915_TILING_NONE)
		return size;

	/* Previous chips need a power-of-two fence region when tiling */
	if (INTEL_INFO(dev)->gen == 3)
		gtt_size = 1024*1024;
	else
		gtt_size = 512*1024;

	while (gtt_size < size)
		gtt_size <<= 1;

	return gtt_size;
}

/**
 * i915_gem_get_gtt_alignment - return required GTT alignment for an object
 * @obj: object to check
 *
 * Return the required GTT alignment for an object, taking into account
 * potential fence register mapping.
 */
uint32_t
i915_gem_get_gtt_alignment(struct drm_device *dev, uint32_t size,
			   int tiling_mode, bool fenced)
{
	/*
	 * Minimum alignment is 4k (GTT page size), but might be greater
	 * if a fence register is needed for the object.
	 */
	if (INTEL_INFO(dev)->gen >= 4 || (!fenced && IS_G33(dev)) ||
	    tiling_mode == I915_TILING_NONE)
		return 4096;

	/*
	 * Previous chips need to be aligned to the size of the smallest
	 * fence register that can contain the object.
	 */
	return i915_gem_get_gtt_size(dev, size, tiling_mode);
}

static int i915_gem_object_create_mmap_offset(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	int ret;

	if (drm_vma_node_has_offset(&obj->base.vma_node))
		return 0;

	dev_priv->mm.shrinker_no_lock_stealing = true;

	ret = drm_gem_create_mmap_offset(&obj->base);
	if (ret != -ENOSPC)
		goto out;

	/* Badly fragmented mmap space? The only way we can recover
	 * space is by destroying unwanted objects. We can't randomly release
	 * mmap_offsets as userspace expects them to be persistent for the
	 * lifetime of the objects. The closest we can is to release the
	 * offsets on purgeable objects by truncating it and marking it purged,
	 * which prevents userspace from ever using that object again.
	 */
	i915_gem_shrink(dev_priv,
			obj->base.size >> PAGE_SHIFT,
			I915_SHRINK_BOUND |
			I915_SHRINK_UNBOUND |
			I915_SHRINK_PURGEABLE);
	ret = drm_gem_create_mmap_offset(&obj->base);
	if (ret != -ENOSPC)
		goto out;

	i915_gem_shrink_all(dev_priv);
	ret = drm_gem_create_mmap_offset(&obj->base);
out:
	dev_priv->mm.shrinker_no_lock_stealing = false;

	return ret;
}

static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj)
{
	drm_gem_free_mmap_offset(&obj->base);
}

int
i915_gem_mmap_gtt(struct drm_file *file,
		  struct drm_device *dev,
		  uint32_t handle,
		  uint64_t *offset)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj;
	int ret;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	if (obj->base.size > dev_priv->gtt.mappable_end) {
		ret = -E2BIG;
		goto out;
	}

	if (obj->madv != I915_MADV_WILLNEED) {
		DRM_DEBUG("Attempting to mmap a purgeable buffer\n");
		ret = -EFAULT;
		goto out;
	}

	ret = i915_gem_object_create_mmap_offset(obj);
	if (ret)
		goto out;

	*offset = drm_vma_node_offset_addr(&obj->base.vma_node);

out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
 * @dev: DRM device
 * @data: GTT mapping ioctl data
 * @file: GEM object info
 *
 * Simply returns the fake offset to userspace so it can mmap it.
 * The mmap call will end up in drm_gem_mmap(), which will set things
 * up so we can get faults in the handler above.
 *
 * The fault handler will take care of binding the object into the GTT
 * (since it may have been evicted to make room for something), allocating
 * a fence register, and mapping the appropriate aperture address into
 * userspace.
 */
int
i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
			struct drm_file *file)
{
	struct drm_i915_gem_mmap_gtt *args = data;

	return i915_gem_mmap_gtt(file, dev, args->handle, &args->offset);
}

static inline int
i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj)
{
	return obj->madv == I915_MADV_DONTNEED;
}

/* Immediately discard the backing storage */
static void
i915_gem_object_truncate(struct drm_i915_gem_object *obj)
{
	i915_gem_object_free_mmap_offset(obj);

	if (obj->base.filp == NULL)
		return;

	/* Our goal here is to return as much of the memory as
	 * is possible back to the system as we are called from OOM.
	 * To do this we must instruct the shmfs to drop all of its
	 * backing pages, *now*.
	 */
	shmem_truncate_range(file_inode(obj->base.filp), 0, (loff_t)-1);
	obj->madv = __I915_MADV_PURGED;
}

/* Try to discard unwanted pages */
static void
i915_gem_object_invalidate(struct drm_i915_gem_object *obj)
{
	struct address_space *mapping;

	switch (obj->madv) {
	case I915_MADV_DONTNEED:
		i915_gem_object_truncate(obj);
	case __I915_MADV_PURGED:
		return;
	}

	if (obj->base.filp == NULL)
		return;

	mapping = file_inode(obj->base.filp)->i_mapping,
	invalidate_mapping_pages(mapping, 0, (loff_t)-1);
}

static void
i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
{
	struct sg_page_iter sg_iter;
	int ret;

	BUG_ON(obj->madv == __I915_MADV_PURGED);

	ret = i915_gem_object_set_to_cpu_domain(obj, true);
	if (ret) {
		/* In the event of a disaster, abandon all caches and
		 * hope for the best.
		 */
		WARN_ON(ret != -EIO);
		i915_gem_clflush_object(obj, true);
		obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
	}

	if (i915_gem_object_needs_bit17_swizzle(obj))
		i915_gem_object_save_bit_17_swizzle(obj);

	if (obj->madv == I915_MADV_DONTNEED)
		obj->dirty = 0;

	for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
		struct page *page = sg_page_iter_page(&sg_iter);

		if (obj->dirty)
			set_page_dirty(page);

		if (obj->madv == I915_MADV_WILLNEED)
			mark_page_accessed(page);

		page_cache_release(page);
	}
	obj->dirty = 0;

	sg_free_table(obj->pages);
	kfree(obj->pages);
}

int
i915_gem_object_put_pages(struct drm_i915_gem_object *obj)
{
	const struct drm_i915_gem_object_ops *ops = obj->ops;

	if (obj->pages == NULL)
		return 0;

	if (obj->pages_pin_count)
		return -EBUSY;

	BUG_ON(i915_gem_obj_bound_any(obj));

	/* ->put_pages might need to allocate memory for the bit17 swizzle
	 * array, hence protect them from being reaped by removing them from gtt
	 * lists early. */
	list_del(&obj->global_list);

	ops->put_pages(obj);
	obj->pages = NULL;

	i915_gem_object_invalidate(obj);

	return 0;
}

unsigned long
i915_gem_shrink(struct drm_i915_private *dev_priv,
		long target, unsigned flags)
{
	const struct {
		struct list_head *list;
		unsigned int bit;
	} phases[] = {
		{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
		{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
		{ NULL, 0 },
	}, *phase;
	unsigned long count = 0;

	/*
	 * As we may completely rewrite the (un)bound list whilst unbinding
	 * (due to retiring requests) we have to strictly process only
	 * one element of the list at the time, and recheck the list
	 * on every iteration.
	 *
	 * In particular, we must hold a reference whilst removing the
	 * object as we may end up waiting for and/or retiring the objects.
	 * This might release the final reference (held by the active list)
	 * and result in the object being freed from under us. This is
	 * similar to the precautions the eviction code must take whilst
	 * removing objects.
	 *
	 * Also note that although these lists do not hold a reference to
	 * the object we can safely grab one here: The final object
	 * unreferencing and the bound_list are both protected by the
	 * dev->struct_mutex and so we won't ever be able to observe an
	 * object on the bound_list with a reference count equals 0.
	 */
	for (phase = phases; phase->list; phase++) {
		struct list_head still_in_list;

		if ((flags & phase->bit) == 0)
			continue;

		INIT_LIST_HEAD(&still_in_list);
		while (count < target && !list_empty(phase->list)) {
			struct drm_i915_gem_object *obj;
			struct i915_vma *vma, *v;

			obj = list_first_entry(phase->list,
					       typeof(*obj), global_list);
			list_move_tail(&obj->global_list, &still_in_list);

			if (flags & I915_SHRINK_PURGEABLE &&
			    !i915_gem_object_is_purgeable(obj))
				continue;

			drm_gem_object_reference(&obj->base);

			/* For the unbound phase, this should be a no-op! */
			list_for_each_entry_safe(vma, v,
						 &obj->vma_list, vma_link)
				if (i915_vma_unbind(vma))
					break;

			if (i915_gem_object_put_pages(obj) == 0)
				count += obj->base.size >> PAGE_SHIFT;

			drm_gem_object_unreference(&obj->base);
		}
		list_splice(&still_in_list, phase->list);
	}

	return count;
}

static unsigned long
i915_gem_shrink_all(struct drm_i915_private *dev_priv)
{
	i915_gem_evict_everything(dev_priv->dev);
	return i915_gem_shrink(dev_priv, LONG_MAX,
			       I915_SHRINK_BOUND | I915_SHRINK_UNBOUND);
}

static int
i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	int page_count, i;
	struct address_space *mapping;
	struct sg_table *st;
	struct scatterlist *sg;
	struct sg_page_iter sg_iter;
	struct page *page;
	unsigned long last_pfn = 0;	/* suppress gcc warning */
	gfp_t gfp;

	/* Assert that the object is not currently in any GPU domain. As it
	 * wasn't in the GTT, there shouldn't be any way it could have been in
	 * a GPU cache
	 */
	BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS);
	BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS);

	st = kmalloc(sizeof(*st), GFP_KERNEL);
	if (st == NULL)
		return -ENOMEM;

	page_count = obj->base.size / PAGE_SIZE;
	if (sg_alloc_table(st, page_count, GFP_KERNEL)) {
		kfree(st);
		return -ENOMEM;
	}

	/* Get the list of pages out of our struct file.  They'll be pinned
	 * at this point until we release them.
	 *
	 * Fail silently without starting the shrinker
	 */
	mapping = file_inode(obj->base.filp)->i_mapping;
	gfp = mapping_gfp_mask(mapping);
	gfp |= __GFP_NORETRY | __GFP_NOWARN | __GFP_NO_KSWAPD;
	gfp &= ~(__GFP_IO | __GFP_WAIT);
	sg = st->sgl;
	st->nents = 0;
	for (i = 0; i < page_count; i++) {
		page = shmem_read_mapping_page_gfp(mapping, i, gfp);
		if (IS_ERR(page)) {
			i915_gem_shrink(dev_priv,
					page_count,
					I915_SHRINK_BOUND |
					I915_SHRINK_UNBOUND |
					I915_SHRINK_PURGEABLE);
			page = shmem_read_mapping_page_gfp(mapping, i, gfp);
		}
		if (IS_ERR(page)) {
			/* We've tried hard to allocate the memory by reaping
			 * our own buffer, now let the real VM do its job and
			 * go down in flames if truly OOM.
			 */
			i915_gem_shrink_all(dev_priv);
			page = shmem_read_mapping_page(mapping, i);
			if (IS_ERR(page))
				goto err_pages;
		}
#ifdef CONFIG_SWIOTLB
		if (swiotlb_nr_tbl()) {
			st->nents++;
			sg_set_page(sg, page, PAGE_SIZE, 0);
			sg = sg_next(sg);
			continue;
		}
#endif
		if (!i || page_to_pfn(page) != last_pfn + 1) {
			if (i)
				sg = sg_next(sg);
			st->nents++;
			sg_set_page(sg, page, PAGE_SIZE, 0);
		} else {
			sg->length += PAGE_SIZE;
		}
		last_pfn = page_to_pfn(page);

		/* Check that the i965g/gm workaround works. */
		WARN_ON((gfp & __GFP_DMA32) && (last_pfn >= 0x00100000UL));
	}
#ifdef CONFIG_SWIOTLB
	if (!swiotlb_nr_tbl())
#endif
		sg_mark_end(sg);
	obj->pages = st;

	if (i915_gem_object_needs_bit17_swizzle(obj))
		i915_gem_object_do_bit_17_swizzle(obj);

	if (obj->tiling_mode != I915_TILING_NONE &&
	    dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES)
		i915_gem_object_pin_pages(obj);

	return 0;

err_pages:
	sg_mark_end(sg);
	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
		page_cache_release(sg_page_iter_page(&sg_iter));
	sg_free_table(st);
	kfree(st);

	/* shmemfs first checks if there is enough memory to allocate the page
	 * and reports ENOSPC should there be insufficient, along with the usual
	 * ENOMEM for a genuine allocation failure.
	 *
	 * We use ENOSPC in our driver to mean that we have run out of aperture
	 * space and so want to translate the error from shmemfs back to our
	 * usual understanding of ENOMEM.
	 */
	if (PTR_ERR(page) == -ENOSPC)
		return -ENOMEM;
	else
		return PTR_ERR(page);
}

/* Ensure that the associated pages are gathered from the backing storage
 * and pinned into our object. i915_gem_object_get_pages() may be called
 * multiple times before they are released by a single call to
 * i915_gem_object_put_pages() - once the pages are no longer referenced
 * either as a result of memory pressure (reaping pages under the shrinker)
 * or as the object is itself released.
 */
int
i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	const struct drm_i915_gem_object_ops *ops = obj->ops;
	int ret;

	if (obj->pages)
		return 0;

	if (obj->madv != I915_MADV_WILLNEED) {
		DRM_DEBUG("Attempting to obtain a purgeable object\n");
		return -EFAULT;
	}

	BUG_ON(obj->pages_pin_count);

	ret = ops->get_pages(obj);
	if (ret)
		return ret;

	list_add_tail(&obj->global_list, &dev_priv->mm.unbound_list);
	return 0;
}

static void
i915_gem_object_move_to_active(struct drm_i915_gem_object *obj,
			       struct intel_engine_cs *ring)
{
	u32 seqno = intel_ring_get_seqno(ring);

	BUG_ON(ring == NULL);
	if (obj->ring != ring && obj->last_write_seqno) {
		/* Keep the seqno relative to the current ring */
		obj->last_write_seqno = seqno;
	}
	obj->ring = ring;

	/* Add a reference if we're newly entering the active list. */
	if (!obj->active) {
		drm_gem_object_reference(&obj->base);
		obj->active = 1;
	}

	list_move_tail(&obj->ring_list, &ring->active_list);

	obj->last_read_seqno = seqno;
}

void i915_vma_move_to_active(struct i915_vma *vma,
			     struct intel_engine_cs *ring)
{
	list_move_tail(&vma->mm_list, &vma->vm->active_list);
	return i915_gem_object_move_to_active(vma->obj, ring);
}

static void
i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	struct i915_address_space *vm;
	struct i915_vma *vma;

	BUG_ON(obj->base.write_domain & ~I915_GEM_GPU_DOMAINS);
	BUG_ON(!obj->active);

	list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
		vma = i915_gem_obj_to_vma(obj, vm);
		if (vma && !list_empty(&vma->mm_list))
			list_move_tail(&vma->mm_list, &vm->inactive_list);
	}

	intel_fb_obj_flush(obj, true);

	list_del_init(&obj->ring_list);
	obj->ring = NULL;

	obj->last_read_seqno = 0;
	obj->last_write_seqno = 0;
	obj->base.write_domain = 0;

	obj->last_fenced_seqno = 0;

	obj->active = 0;
	drm_gem_object_unreference(&obj->base);

	WARN_ON(i915_verify_lists(dev));
}

static void
i915_gem_object_retire(struct drm_i915_gem_object *obj)
{
	struct intel_engine_cs *ring = obj->ring;

	if (ring == NULL)
		return;

	if (i915_seqno_passed(ring->get_seqno(ring, true),
			      obj->last_read_seqno))
		i915_gem_object_move_to_inactive(obj);
}

static int
i915_gem_init_seqno(struct drm_device *dev, u32 seqno)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int ret, i, j;

	/* Carefully retire all requests without writing to the rings */
	for_each_ring(ring, dev_priv, i) {
		ret = intel_ring_idle(ring);
		if (ret)
			return ret;
	}
	i915_gem_retire_requests(dev);

	/* Finally reset hw state */
	for_each_ring(ring, dev_priv, i) {
		intel_ring_init_seqno(ring, seqno);

		for (j = 0; j < ARRAY_SIZE(ring->semaphore.sync_seqno); j++)
			ring->semaphore.sync_seqno[j] = 0;
	}

	return 0;
}

int i915_gem_set_seqno(struct drm_device *dev, u32 seqno)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	if (seqno == 0)
		return -EINVAL;

	/* HWS page needs to be set less than what we
	 * will inject to ring
	 */
	ret = i915_gem_init_seqno(dev, seqno - 1);
	if (ret)
		return ret;

	/* Carefully set the last_seqno value so that wrap
	 * detection still works
	 */
	dev_priv->next_seqno = seqno;
	dev_priv->last_seqno = seqno - 1;
	if (dev_priv->last_seqno == 0)
		dev_priv->last_seqno--;

	return 0;
}

int
i915_gem_get_seqno(struct drm_device *dev, u32 *seqno)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	/* reserve 0 for non-seqno */
	if (dev_priv->next_seqno == 0) {
		int ret = i915_gem_init_seqno(dev, 0);
		if (ret)
			return ret;

		dev_priv->next_seqno = 1;
	}

	*seqno = dev_priv->last_seqno = dev_priv->next_seqno++;
	return 0;
}

int __i915_add_request(struct intel_engine_cs *ring,
		       struct drm_file *file,
		       struct drm_i915_gem_object *obj,
		       u32 *out_seqno)
{
	struct drm_i915_private *dev_priv = ring->dev->dev_private;
	struct drm_i915_gem_request *request;
	struct intel_ringbuffer *ringbuf;
	u32 request_ring_position, request_start;
	int ret;

	request = ring->preallocated_lazy_request;
	if (WARN_ON(request == NULL))
		return -ENOMEM;

	if (i915.enable_execlists) {
		struct intel_context *ctx = request->ctx;
		ringbuf = ctx->engine[ring->id].ringbuf;
	} else
		ringbuf = ring->buffer;

	request_start = intel_ring_get_tail(ringbuf);
	/*
	 * Emit any outstanding flushes - execbuf can fail to emit the flush
	 * after having emitted the batchbuffer command. Hence we need to fix
	 * things up similar to emitting the lazy request. The difference here
	 * is that the flush _must_ happen before the next request, no matter
	 * what.
	 */
	if (i915.enable_execlists) {
		ret = logical_ring_flush_all_caches(ringbuf);
		if (ret)
			return ret;
	} else {
		ret = intel_ring_flush_all_caches(ring);
		if (ret)
			return ret;
	}

	/* Record the position of the start of the request so that
	 * should we detect the updated seqno part-way through the
	 * GPU processing the request, we never over-estimate the
	 * position of the head.
	 */
	request_ring_position = intel_ring_get_tail(ringbuf);

	if (i915.enable_execlists) {
		ret = ring->emit_request(ringbuf);
		if (ret)
			return ret;
	} else {
		ret = ring->add_request(ring);
		if (ret)
			return ret;
	}

	request->seqno = intel_ring_get_seqno(ring);
	request->ring = ring;
	request->head = request_start;
	request->tail = request_ring_position;

	/* Whilst this request exists, batch_obj will be on the
	 * active_list, and so will hold the active reference. Only when this
	 * request is retired will the the batch_obj be moved onto the
	 * inactive_list and lose its active reference. Hence we do not need
	 * to explicitly hold another reference here.
	 */
	request->batch_obj = obj;

	if (!i915.enable_execlists) {
		/* Hold a reference to the current context so that we can inspect
		 * it later in case a hangcheck error event fires.
		 */
		request->ctx = ring->last_context;
		if (request->ctx)
			i915_gem_context_reference(request->ctx);
	}

	request->emitted_jiffies = jiffies;
	list_add_tail(&request->list, &ring->request_list);
	request->file_priv = NULL;

	if (file) {
		struct drm_i915_file_private *file_priv = file->driver_priv;

		spin_lock(&file_priv->mm.lock);
		request->file_priv = file_priv;
		list_add_tail(&request->client_list,
			      &file_priv->mm.request_list);
		spin_unlock(&file_priv->mm.lock);
	}

	trace_i915_gem_request_add(ring, request->seqno);
	ring->outstanding_lazy_seqno = 0;
	ring->preallocated_lazy_request = NULL;

	i915_queue_hangcheck(ring->dev);

	cancel_delayed_work_sync(&dev_priv->mm.idle_work);
	queue_delayed_work(dev_priv->wq,
			   &dev_priv->mm.retire_work,
			   round_jiffies_up_relative(HZ));
	intel_mark_busy(dev_priv->dev);

	if (out_seqno)
		*out_seqno = request->seqno;
	return 0;
}

static inline void
i915_gem_request_remove_from_client(struct drm_i915_gem_request *request)
{
	struct drm_i915_file_private *file_priv = request->file_priv;

	if (!file_priv)
		return;

	spin_lock(&file_priv->mm.lock);
	list_del(&request->client_list);
	request->file_priv = NULL;
	spin_unlock(&file_priv->mm.lock);
}

static bool i915_context_is_banned(struct drm_i915_private *dev_priv,
				   const struct intel_context *ctx)
{
	unsigned long elapsed;

	elapsed = get_seconds() - ctx->hang_stats.guilty_ts;

	if (ctx->hang_stats.banned)
		return true;

	if (elapsed <= DRM_I915_CTX_BAN_PERIOD) {
		if (!i915_gem_context_is_default(ctx)) {
			DRM_DEBUG("context hanging too fast, banning!\n");
			return true;
		} else if (i915_stop_ring_allow_ban(dev_priv)) {
			if (i915_stop_ring_allow_warn(dev_priv))
				DRM_ERROR("gpu hanging too fast, banning!\n");
			return true;
		}
	}

	return false;
}

static void i915_set_reset_status(struct drm_i915_private *dev_priv,
				  struct intel_context *ctx,
				  const bool guilty)
{
	struct i915_ctx_hang_stats *hs;

	if (WARN_ON(!ctx))
		return;

	hs = &ctx->hang_stats;

	if (guilty) {
		hs->banned = i915_context_is_banned(dev_priv, ctx);
		hs->batch_active++;
		hs->guilty_ts = get_seconds();
	} else {
		hs->batch_pending++;
	}
}

static void i915_gem_free_request(struct drm_i915_gem_request *request)
{
	struct intel_context *ctx = request->ctx;

	list_del(&request->list);
	i915_gem_request_remove_from_client(request);

	if (ctx) {
		if (i915.enable_execlists) {
			struct intel_engine_cs *ring = request->ring;

			if (ctx != ring->default_context)
				intel_lr_context_unpin(ring, ctx);
		}
		i915_gem_context_unreference(ctx);
	}
	kfree(request);
}

struct drm_i915_gem_request *
i915_gem_find_active_request(struct intel_engine_cs *ring)
{
	struct drm_i915_gem_request *request;
	u32 completed_seqno;

	completed_seqno = ring->get_seqno(ring, false);

	list_for_each_entry(request, &ring->request_list, list) {
		if (i915_seqno_passed(completed_seqno, request->seqno))
			continue;

		return request;
	}

	return NULL;
}

static void i915_gem_reset_ring_status(struct drm_i915_private *dev_priv,
				       struct intel_engine_cs *ring)
{
	struct drm_i915_gem_request *request;
	bool ring_hung;

	request = i915_gem_find_active_request(ring);

	if (request == NULL)
		return;

	ring_hung = ring->hangcheck.score >= HANGCHECK_SCORE_RING_HUNG;

	i915_set_reset_status(dev_priv, request->ctx, ring_hung);

	list_for_each_entry_continue(request, &ring->request_list, list)
		i915_set_reset_status(dev_priv, request->ctx, false);
}

static void i915_gem_reset_ring_cleanup(struct drm_i915_private *dev_priv,
					struct intel_engine_cs *ring)
{
	while (!list_empty(&ring->active_list)) {
		struct drm_i915_gem_object *obj;

		obj = list_first_entry(&ring->active_list,
				       struct drm_i915_gem_object,
				       ring_list);

		i915_gem_object_move_to_inactive(obj);
	}

	/*
	 * Clear the execlists queue up before freeing the requests, as those
	 * are the ones that keep the context and ringbuffer backing objects
	 * pinned in place.
	 */
	while (!list_empty(&ring->execlist_queue)) {
		struct intel_ctx_submit_request *submit_req;

		submit_req = list_first_entry(&ring->execlist_queue,
				struct intel_ctx_submit_request,
				execlist_link);
		list_del(&submit_req->execlist_link);
		intel_runtime_pm_put(dev_priv);
		i915_gem_context_unreference(submit_req->ctx);
		kfree(submit_req);
	}

	/*
	 * We must free the requests after all the corresponding objects have
	 * been moved off active lists. Which is the same order as the normal
	 * retire_requests function does. This is important if object hold
	 * implicit references on things like e.g. ppgtt address spaces through
	 * the request.
	 */
	while (!list_empty(&ring->request_list)) {
		struct drm_i915_gem_request *request;

		request = list_first_entry(&ring->request_list,
					   struct drm_i915_gem_request,
					   list);

		i915_gem_free_request(request);
	}

	/* These may not have been flush before the reset, do so now */
	kfree(ring->preallocated_lazy_request);
	ring->preallocated_lazy_request = NULL;
	ring->outstanding_lazy_seqno = 0;
}

void i915_gem_restore_fences(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int i;

	for (i = 0; i < dev_priv->num_fence_regs; i++) {
		struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i];

		/*
		 * Commit delayed tiling changes if we have an object still
		 * attached to the fence, otherwise just clear the fence.
		 */
		if (reg->obj) {
			i915_gem_object_update_fence(reg->obj, reg,
						     reg->obj->tiling_mode);
		} else {
			i915_gem_write_fence(dev, i, NULL);
		}
	}
}

void i915_gem_reset(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int i;

	/*
	 * Before we free the objects from the requests, we need to inspect
	 * them for finding the guilty party. As the requests only borrow
	 * their reference to the objects, the inspection must be done first.
	 */
	for_each_ring(ring, dev_priv, i)
		i915_gem_reset_ring_status(dev_priv, ring);

	for_each_ring(ring, dev_priv, i)
		i915_gem_reset_ring_cleanup(dev_priv, ring);

	i915_gem_context_reset(dev);

	i915_gem_restore_fences(dev);
}

/**
 * This function clears the request list as sequence numbers are passed.
 */
void
i915_gem_retire_requests_ring(struct intel_engine_cs *ring)
{
	uint32_t seqno;

	if (list_empty(&ring->request_list))
		return;

	WARN_ON(i915_verify_lists(ring->dev));

	seqno = ring->get_seqno(ring, true);

	/* Move any buffers on the active list that are no longer referenced
	 * by the ringbuffer to the flushing/inactive lists as appropriate,
	 * before we free the context associated with the requests.
	 */
	while (!list_empty(&ring->active_list)) {
		struct drm_i915_gem_object *obj;

		obj = list_first_entry(&ring->active_list,
				      struct drm_i915_gem_object,
				      ring_list);

		if (!i915_seqno_passed(seqno, obj->last_read_seqno))
			break;

		i915_gem_object_move_to_inactive(obj);
	}


	while (!list_empty(&ring->request_list)) {
		struct drm_i915_gem_request *request;
		struct intel_ringbuffer *ringbuf;

		request = list_first_entry(&ring->request_list,
					   struct drm_i915_gem_request,
					   list);

		if (!i915_seqno_passed(seqno, request->seqno))
			break;

		trace_i915_gem_request_retire(ring, request->seqno);

		/* This is one of the few common intersection points
		 * between legacy ringbuffer submission and execlists:
		 * we need to tell them apart in order to find the correct
		 * ringbuffer to which the request belongs to.
		 */
		if (i915.enable_execlists) {
			struct intel_context *ctx = request->ctx;
			ringbuf = ctx->engine[ring->id].ringbuf;
		} else
			ringbuf = ring->buffer;

		/* We know the GPU must have read the request to have
		 * sent us the seqno + interrupt, so use the position
		 * of tail of the request to update the last known position
		 * of the GPU head.
		 */
		ringbuf->last_retired_head = request->tail;

		i915_gem_free_request(request);
	}

	if (unlikely(ring->trace_irq_seqno &&
		     i915_seqno_passed(seqno, ring->trace_irq_seqno))) {
		ring->irq_put(ring);
		ring->trace_irq_seqno = 0;
	}

	WARN_ON(i915_verify_lists(ring->dev));
}

bool
i915_gem_retire_requests(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	bool idle = true;
	int i;

	for_each_ring(ring, dev_priv, i) {
		i915_gem_retire_requests_ring(ring);
		idle &= list_empty(&ring->request_list);
		if (i915.enable_execlists) {
			unsigned long flags;

			spin_lock_irqsave(&ring->execlist_lock, flags);
			idle &= list_empty(&ring->execlist_queue);
			spin_unlock_irqrestore(&ring->execlist_lock, flags);

			intel_execlists_retire_requests(ring);
		}
	}

	if (idle)
		mod_delayed_work(dev_priv->wq,
				   &dev_priv->mm.idle_work,
				   msecs_to_jiffies(100));

	return idle;
}

static void
i915_gem_retire_work_handler(struct work_struct *work)
{
	struct drm_i915_private *dev_priv =
		container_of(work, typeof(*dev_priv), mm.retire_work.work);
	struct drm_device *dev = dev_priv->dev;
	bool idle;

	/* Come back later if the device is busy... */
	idle = false;
	if (mutex_trylock(&dev->struct_mutex)) {
		idle = i915_gem_retire_requests(dev);
		mutex_unlock(&dev->struct_mutex);
	}
	if (!idle)
		queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work,
				   round_jiffies_up_relative(HZ));
}

static void
i915_gem_idle_work_handler(struct work_struct *work)
{
	struct drm_i915_private *dev_priv =
		container_of(work, typeof(*dev_priv), mm.idle_work.work);

	intel_mark_idle(dev_priv->dev);
}

/**
 * Ensures that an object will eventually get non-busy by flushing any required
 * write domains, emitting any outstanding lazy request and retiring and
 * completed requests.
 */
static int
i915_gem_object_flush_active(struct drm_i915_gem_object *obj)
{
	int ret;

	if (obj->active) {
		ret = i915_gem_check_olr(obj->ring, obj->last_read_seqno);
		if (ret)
			return ret;

		i915_gem_retire_requests_ring(obj->ring);
	}

	return 0;
}

/**
 * i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
 * @DRM_IOCTL_ARGS: standard ioctl arguments
 *
 * Returns 0 if successful, else an error is returned with the remaining time in
 * the timeout parameter.
 *  -ETIME: object is still busy after timeout
 *  -ERESTARTSYS: signal interrupted the wait
 *  -ENONENT: object doesn't exist
 * Also possible, but rare:
 *  -EAGAIN: GPU wedged
 *  -ENOMEM: damn
 *  -ENODEV: Internal IRQ fail
 *  -E?: The add request failed
 *
 * The wait ioctl with a timeout of 0 reimplements the busy ioctl. With any
 * non-zero timeout parameter the wait ioctl will wait for the given number of
 * nanoseconds on an object becoming unbusy. Since the wait itself does so
 * without holding struct_mutex the object may become re-busied before this
 * function completes. A similar but shorter * race condition exists in the busy
 * ioctl
 */
int
i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_wait *args = data;
	struct drm_i915_gem_object *obj;
	struct intel_engine_cs *ring = NULL;
	unsigned reset_counter;
	u32 seqno = 0;
	int ret = 0;

	if (args->flags != 0)
		return -EINVAL;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->bo_handle));
	if (&obj->base == NULL) {
		mutex_unlock(&dev->struct_mutex);
		return -ENOENT;
	}

	/* Need to make sure the object gets inactive eventually. */
	ret = i915_gem_object_flush_active(obj);
	if (ret)
		goto out;

	if (obj->active) {
		seqno = obj->last_read_seqno;
		ring = obj->ring;
	}

	if (seqno == 0)
		 goto out;

	/* Do this after OLR check to make sure we make forward progress polling
	 * on this IOCTL with a timeout <=0 (like busy ioctl)
	 */
	if (args->timeout_ns <= 0) {
		ret = -ETIME;
		goto out;
	}

	drm_gem_object_unreference(&obj->base);
	reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter);
	mutex_unlock(&dev->struct_mutex);

	return __i915_wait_seqno(ring, seqno, reset_counter, true,
				 &args->timeout_ns, file->driver_priv);

out:
	drm_gem_object_unreference(&obj->base);
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * i915_gem_object_sync - sync an object to a ring.
 *
 * @obj: object which may be in use on another ring.
 * @to: ring we wish to use the object on. May be NULL.
 *
 * This code is meant to abstract object synchronization with the GPU.
 * Calling with NULL implies synchronizing the object with the CPU
 * rather than a particular GPU ring.
 *
 * Returns 0 if successful, else propagates up the lower layer error.
 */
int
i915_gem_object_sync(struct drm_i915_gem_object *obj,
		     struct intel_engine_cs *to)
{
	struct intel_engine_cs *from = obj->ring;
	u32 seqno;
	int ret, idx;

	if (from == NULL || to == from)
		return 0;

	if (to == NULL || !i915_semaphore_is_enabled(obj->base.dev))
		return i915_gem_object_wait_rendering(obj, false);

	idx = intel_ring_sync_index(from, to);

	seqno = obj->last_read_seqno;
	/* Optimization: Avoid semaphore sync when we are sure we already
	 * waited for an object with higher seqno */
	if (seqno <= from->semaphore.sync_seqno[idx])
		return 0;

	ret = i915_gem_check_olr(obj->ring, seqno);
	if (ret)
		return ret;

	trace_i915_gem_ring_sync_to(from, to, seqno);
	ret = to->semaphore.sync_to(to, from, seqno);
	if (!ret)
		/* We use last_read_seqno because sync_to()
		 * might have just caused seqno wrap under
		 * the radar.
		 */
		from->semaphore.sync_seqno[idx] = obj->last_read_seqno;

	return ret;
}

static void i915_gem_object_finish_gtt(struct drm_i915_gem_object *obj)
{
	u32 old_write_domain, old_read_domains;

	/* Force a pagefault for domain tracking on next user access */
	i915_gem_release_mmap(obj);

	if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
		return;

	/* Wait for any direct GTT access to complete */
	mb();

	old_read_domains = obj->base.read_domains;
	old_write_domain = obj->base.write_domain;

	obj->base.read_domains &= ~I915_GEM_DOMAIN_GTT;
	obj->base.write_domain &= ~I915_GEM_DOMAIN_GTT;

	trace_i915_gem_object_change_domain(obj,
					    old_read_domains,
					    old_write_domain);
}

int i915_vma_unbind(struct i915_vma *vma)
{
	struct drm_i915_gem_object *obj = vma->obj;
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	int ret;

	if (list_empty(&vma->vma_link))
		return 0;

	if (!drm_mm_node_allocated(&vma->node)) {
		i915_gem_vma_destroy(vma);
		return 0;
	}

	if (vma->pin_count)
		return -EBUSY;

	BUG_ON(obj->pages == NULL);

	ret = i915_gem_object_finish_gpu(obj);
	if (ret)
		return ret;
	/* Continue on if we fail due to EIO, the GPU is hung so we
	 * should be safe and we need to cleanup or else we might
	 * cause memory corruption through use-after-free.
	 */

	/* Throw away the active reference before moving to the unbound list */
	i915_gem_object_retire(obj);

	if (i915_is_ggtt(vma->vm)) {
		i915_gem_object_finish_gtt(obj);

		/* release the fence reg _after_ flushing */
		ret = i915_gem_object_put_fence(obj);
		if (ret)
			return ret;
	}

	trace_i915_vma_unbind(vma);

	vma->unbind_vma(vma);

	list_del_init(&vma->mm_list);
	if (i915_is_ggtt(vma->vm))
		obj->map_and_fenceable = false;

	drm_mm_remove_node(&vma->node);
	i915_gem_vma_destroy(vma);

	/* Since the unbound list is global, only move to that list if
	 * no more VMAs exist. */
	if (list_empty(&obj->vma_list)) {
		i915_gem_gtt_finish_object(obj);
		list_move_tail(&obj->global_list, &dev_priv->mm.unbound_list);
	}

	/* And finally now the object is completely decoupled from this vma,
	 * we can drop its hold on the backing storage and allow it to be
	 * reaped by the shrinker.
	 */
	i915_gem_object_unpin_pages(obj);

	return 0;
}

int i915_gpu_idle(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int ret, i;

	/* Flush everything onto the inactive list. */
	for_each_ring(ring, dev_priv, i) {
		if (!i915.enable_execlists) {
			ret = i915_switch_context(ring, ring->default_context);
			if (ret)
				return ret;
		}

		ret = intel_ring_idle(ring);
		if (ret)
			return ret;
	}

	return 0;
}

static void i965_write_fence_reg(struct drm_device *dev, int reg,
				 struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int fence_reg;
	int fence_pitch_shift;

	if (INTEL_INFO(dev)->gen >= 6) {
		fence_reg = FENCE_REG_SANDYBRIDGE_0;
		fence_pitch_shift = SANDYBRIDGE_FENCE_PITCH_SHIFT;
	} else {
		fence_reg = FENCE_REG_965_0;
		fence_pitch_shift = I965_FENCE_PITCH_SHIFT;
	}

	fence_reg += reg * 8;

	/* To w/a incoherency with non-atomic 64-bit register updates,
	 * we split the 64-bit update into two 32-bit writes. In order
	 * for a partial fence not to be evaluated between writes, we
	 * precede the update with write to turn off the fence register,
	 * and only enable the fence as the last step.
	 *
	 * For extra levels of paranoia, we make sure each step lands
	 * before applying the next step.
	 */
	I915_WRITE(fence_reg, 0);
	POSTING_READ(fence_reg);

	if (obj) {
		u32 size = i915_gem_obj_ggtt_size(obj);
		uint64_t val;

		/* Adjust fence size to match tiled area */
		if (obj->tiling_mode != I915_TILING_NONE) {
			uint32_t row_size = obj->stride *
				(obj->tiling_mode == I915_TILING_Y ? 32 : 8);
			size = (size / row_size) * row_size;
		}

		val = (uint64_t)((i915_gem_obj_ggtt_offset(obj) + size - 4096) &
				 0xfffff000) << 32;
		val |= i915_gem_obj_ggtt_offset(obj) & 0xfffff000;
		val |= (uint64_t)((obj->stride / 128) - 1) << fence_pitch_shift;
		if (obj->tiling_mode == I915_TILING_Y)
			val |= 1 << I965_FENCE_TILING_Y_SHIFT;
		val |= I965_FENCE_REG_VALID;

		I915_WRITE(fence_reg + 4, val >> 32);
		POSTING_READ(fence_reg + 4);

		I915_WRITE(fence_reg + 0, val);
		POSTING_READ(fence_reg);
	} else {
		I915_WRITE(fence_reg + 4, 0);
		POSTING_READ(fence_reg + 4);
	}
}

static void i915_write_fence_reg(struct drm_device *dev, int reg,
				 struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 val;

	if (obj) {
		u32 size = i915_gem_obj_ggtt_size(obj);
		int pitch_val;
		int tile_width;

		WARN((i915_gem_obj_ggtt_offset(obj) & ~I915_FENCE_START_MASK) ||
		     (size & -size) != size ||
		     (i915_gem_obj_ggtt_offset(obj) & (size - 1)),
		     "object 0x%08lx [fenceable? %d] not 1M or pot-size (0x%08x) aligned\n",
		     i915_gem_obj_ggtt_offset(obj), obj->map_and_fenceable, size);

		if (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))
			tile_width = 128;
		else
			tile_width = 512;

		/* Note: pitch better be a power of two tile widths */
		pitch_val = obj->stride / tile_width;
		pitch_val = ffs(pitch_val) - 1;

		val = i915_gem_obj_ggtt_offset(obj);
		if (obj->tiling_mode == I915_TILING_Y)
			val |= 1 << I830_FENCE_TILING_Y_SHIFT;
		val |= I915_FENCE_SIZE_BITS(size);
		val |= pitch_val << I830_FENCE_PITCH_SHIFT;
		val |= I830_FENCE_REG_VALID;
	} else
		val = 0;

	if (reg < 8)
		reg = FENCE_REG_830_0 + reg * 4;
	else
		reg = FENCE_REG_945_8 + (reg - 8) * 4;

	I915_WRITE(reg, val);
	POSTING_READ(reg);
}

static void i830_write_fence_reg(struct drm_device *dev, int reg,
				struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t val;

	if (obj) {
		u32 size = i915_gem_obj_ggtt_size(obj);
		uint32_t pitch_val;

		WARN((i915_gem_obj_ggtt_offset(obj) & ~I830_FENCE_START_MASK) ||
		     (size & -size) != size ||
		     (i915_gem_obj_ggtt_offset(obj) & (size - 1)),
		     "object 0x%08lx not 512K or pot-size 0x%08x aligned\n",
		     i915_gem_obj_ggtt_offset(obj), size);

		pitch_val = obj->stride / 128;
		pitch_val = ffs(pitch_val) - 1;

		val = i915_gem_obj_ggtt_offset(obj);
		if (obj->tiling_mode == I915_TILING_Y)
			val |= 1 << I830_FENCE_TILING_Y_SHIFT;
		val |= I830_FENCE_SIZE_BITS(size);
		val |= pitch_val << I830_FENCE_PITCH_SHIFT;
		val |= I830_FENCE_REG_VALID;
	} else
		val = 0;

	I915_WRITE(FENCE_REG_830_0 + reg * 4, val);
	POSTING_READ(FENCE_REG_830_0 + reg * 4);
}

inline static bool i915_gem_object_needs_mb(struct drm_i915_gem_object *obj)
{
	return obj && obj->base.read_domains & I915_GEM_DOMAIN_GTT;
}

static void i915_gem_write_fence(struct drm_device *dev, int reg,
				 struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	/* Ensure that all CPU reads are completed before installing a fence
	 * and all writes before removing the fence.
	 */
	if (i915_gem_object_needs_mb(dev_priv->fence_regs[reg].obj))
		mb();

	WARN(obj && (!obj->stride || !obj->tiling_mode),
	     "bogus fence setup with stride: 0x%x, tiling mode: %i\n",
	     obj->stride, obj->tiling_mode);

	switch (INTEL_INFO(dev)->gen) {
	case 9:
	case 8:
	case 7:
	case 6:
	case 5:
	case 4: i965_write_fence_reg(dev, reg, obj); break;
	case 3: i915_write_fence_reg(dev, reg, obj); break;
	case 2: i830_write_fence_reg(dev, reg, obj); break;
	default: BUG();
	}

	/* And similarly be paranoid that no direct access to this region
	 * is reordered to before the fence is installed.
	 */
	if (i915_gem_object_needs_mb(obj))
		mb();
}

static inline int fence_number(struct drm_i915_private *dev_priv,
			       struct drm_i915_fence_reg *fence)
{
	return fence - dev_priv->fence_regs;
}

static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj,
					 struct drm_i915_fence_reg *fence,
					 bool enable)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	int reg = fence_number(dev_priv, fence);

	i915_gem_write_fence(obj->base.dev, reg, enable ? obj : NULL);

	if (enable) {
		obj->fence_reg = reg;
		fence->obj = obj;
		list_move_tail(&fence->lru_list, &dev_priv->mm.fence_list);
	} else {
		obj->fence_reg = I915_FENCE_REG_NONE;
		fence->obj = NULL;
		list_del_init(&fence->lru_list);
	}
	obj->fence_dirty = false;
}

static int
i915_gem_object_wait_fence(struct drm_i915_gem_object *obj)
{
	if (obj->last_fenced_seqno) {
		int ret = i915_wait_seqno(obj->ring, obj->last_fenced_seqno);
		if (ret)
			return ret;

		obj->last_fenced_seqno = 0;
	}

	return 0;
}

int
i915_gem_object_put_fence(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	struct drm_i915_fence_reg *fence;
	int ret;

	ret = i915_gem_object_wait_fence(obj);
	if (ret)
		return ret;

	if (obj->fence_reg == I915_FENCE_REG_NONE)
		return 0;

	fence = &dev_priv->fence_regs[obj->fence_reg];

	if (WARN_ON(fence->pin_count))
		return -EBUSY;

	i915_gem_object_fence_lost(obj);
	i915_gem_object_update_fence(obj, fence, false);

	return 0;
}

static struct drm_i915_fence_reg *
i915_find_fence_reg(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_fence_reg *reg, *avail;
	int i;

	/* First try to find a free reg */
	avail = NULL;
	for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) {
		reg = &dev_priv->fence_regs[i];
		if (!reg->obj)
			return reg;

		if (!reg->pin_count)
			avail = reg;
	}

	if (avail == NULL)
		goto deadlock;

	/* None available, try to steal one or wait for a user to finish */
	list_for_each_entry(reg, &dev_priv->mm.fence_list, lru_list) {
		if (reg->pin_count)
			continue;

		return reg;
	}

deadlock:
	/* Wait for completion of pending flips which consume fences */
	if (intel_has_pending_fb_unpin(dev))
		return ERR_PTR(-EAGAIN);

	return ERR_PTR(-EDEADLK);
}

/**
 * i915_gem_object_get_fence - set up fencing for an object
 * @obj: object to map through a fence reg
 *
 * When mapping objects through the GTT, userspace wants to be able to write
 * to them without having to worry about swizzling if the object is tiled.
 * This function walks the fence regs looking for a free one for @obj,
 * stealing one if it can't find any.
 *
 * It then sets up the reg based on the object's properties: address, pitch
 * and tiling format.
 *
 * For an untiled surface, this removes any existing fence.
 */
int
i915_gem_object_get_fence(struct drm_i915_gem_object *obj)
{
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	bool enable = obj->tiling_mode != I915_TILING_NONE;
	struct drm_i915_fence_reg *reg;
	int ret;

	/* Have we updated the tiling parameters upon the object and so
	 * will need to serialise the write to the associated fence register?
	 */
	if (obj->fence_dirty) {
		ret = i915_gem_object_wait_fence(obj);
		if (ret)
			return ret;
	}

	/* Just update our place in the LRU if our fence is getting reused. */
	if (obj->fence_reg != I915_FENCE_REG_NONE) {
		reg = &dev_priv->fence_regs[obj->fence_reg];
		if (!obj->fence_dirty) {
			list_move_tail(&reg->lru_list,
				       &dev_priv->mm.fence_list);
			return 0;
		}
	} else if (enable) {
		if (WARN_ON(!obj->map_and_fenceable))
			return -EINVAL;

		reg = i915_find_fence_reg(dev);
		if (IS_ERR(reg))
			return PTR_ERR(reg);

		if (reg->obj) {
			struct drm_i915_gem_object *old = reg->obj;

			ret = i915_gem_object_wait_fence(old);
			if (ret)
				return ret;

			i915_gem_object_fence_lost(old);
		}
	} else
		return 0;

	i915_gem_object_update_fence(obj, reg, enable);

	return 0;
}

static bool i915_gem_valid_gtt_space(struct i915_vma *vma,
				     unsigned long cache_level)
{
	struct drm_mm_node *gtt_space = &vma->node;
	struct drm_mm_node *other;

	/*
	 * On some machines we have to be careful when putting differing types
	 * of snoopable memory together to avoid the prefetcher crossing memory
	 * domains and dying. During vm initialisation, we decide whether or not
	 * these constraints apply and set the drm_mm.color_adjust
	 * appropriately.
	 */
	if (vma->vm->mm.color_adjust == NULL)
		return true;

	if (!drm_mm_node_allocated(gtt_space))
		return true;

	if (list_empty(&gtt_space->node_list))
		return true;

	other = list_entry(gtt_space->node_list.prev, struct drm_mm_node, node_list);
	if (other->allocated && !other->hole_follows && other->color != cache_level)
		return false;

	other = list_entry(gtt_space->node_list.next, struct drm_mm_node, node_list);
	if (other->allocated && !gtt_space->hole_follows && other->color != cache_level)
		return false;

	return true;
}

/**
 * Finds free space in the GTT aperture and binds the object there.
 */
static struct i915_vma *
i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
			   struct i915_address_space *vm,
			   unsigned alignment,
			   uint64_t flags)
{
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 size, fence_size, fence_alignment, unfenced_alignment;
	unsigned long start =
		flags & PIN_OFFSET_BIAS ? flags & PIN_OFFSET_MASK : 0;
	unsigned long end =
		flags & PIN_MAPPABLE ? dev_priv->gtt.mappable_end : vm->total;
	struct i915_vma *vma;
	int ret;

	fence_size = i915_gem_get_gtt_size(dev,
					   obj->base.size,
					   obj->tiling_mode);
	fence_alignment = i915_gem_get_gtt_alignment(dev,
						     obj->base.size,
						     obj->tiling_mode, true);
	unfenced_alignment =
		i915_gem_get_gtt_alignment(dev,
					   obj->base.size,
					   obj->tiling_mode, false);

	if (alignment == 0)
		alignment = flags & PIN_MAPPABLE ? fence_alignment :
						unfenced_alignment;
	if (flags & PIN_MAPPABLE && alignment & (fence_alignment - 1)) {
		DRM_DEBUG("Invalid object alignment requested %u\n", alignment);
		return ERR_PTR(-EINVAL);
	}

	size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;

	/* If the object is bigger than the entire aperture, reject it early
	 * before evicting everything in a vain attempt to find space.
	 */
	if (obj->base.size > end) {
		DRM_DEBUG("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%lu\n",
			  obj->base.size,
			  flags & PIN_MAPPABLE ? "mappable" : "total",
			  end);
		return ERR_PTR(-E2BIG);
	}

	ret = i915_gem_object_get_pages(obj);
	if (ret)
		return ERR_PTR(ret);

	i915_gem_object_pin_pages(obj);

	vma = i915_gem_obj_lookup_or_create_vma(obj, vm);
	if (IS_ERR(vma))
		goto err_unpin;

search_free:
	ret = drm_mm_insert_node_in_range_generic(&vm->mm, &vma->node,
						  size, alignment,
						  obj->cache_level,
						  start, end,
						  DRM_MM_SEARCH_DEFAULT,
						  DRM_MM_CREATE_DEFAULT);
	if (ret) {
		ret = i915_gem_evict_something(dev, vm, size, alignment,
					       obj->cache_level,
					       start, end,
					       flags);
		if (ret == 0)
			goto search_free;

		goto err_free_vma;
	}
	if (WARN_ON(!i915_gem_valid_gtt_space(vma, obj->cache_level))) {
		ret = -EINVAL;
		goto err_remove_node;
	}

	ret = i915_gem_gtt_prepare_object(obj);
	if (ret)
		goto err_remove_node;

	list_move_tail(&obj->global_list, &dev_priv->mm.bound_list);
	list_add_tail(&vma->mm_list, &vm->inactive_list);

	trace_i915_vma_bind(vma, flags);
	vma->bind_vma(vma, obj->cache_level,
		      flags & PIN_GLOBAL ? GLOBAL_BIND : 0);

	return vma;

err_remove_node:
	drm_mm_remove_node(&vma->node);
err_free_vma:
	i915_gem_vma_destroy(vma);
	vma = ERR_PTR(ret);
err_unpin:
	i915_gem_object_unpin_pages(obj);
	return vma;
}

bool
i915_gem_clflush_object(struct drm_i915_gem_object *obj,
			bool force)
{
	/* If we don't have a page list set up, then we're not pinned
	 * to GPU, and we can ignore the cache flush because it'll happen
	 * again at bind time.
	 */
	if (obj->pages == NULL)
		return false;

	/*
	 * Stolen memory is always coherent with the GPU as it is explicitly
	 * marked as wc by the system, or the system is cache-coherent.
	 */
	if (obj->stolen || obj->phys_handle)
		return false;

	/* If the GPU is snooping the contents of the CPU cache,
	 * we do not need to manually clear the CPU cache lines.  However,
	 * the caches are only snooped when the render cache is
	 * flushed/invalidated.  As we always have to emit invalidations
	 * and flushes when moving into and out of the RENDER domain, correct
	 * snooping behaviour occurs naturally as the result of our domain
	 * tracking.
	 */
	if (!force && cpu_cache_is_coherent(obj->base.dev, obj->cache_level))
		return false;

	trace_i915_gem_object_clflush(obj);
	drm_clflush_sg(obj->pages);

	return true;
}

/** Flushes the GTT write domain for the object if it's dirty. */
static void
i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj)
{
	uint32_t old_write_domain;

	if (obj->base.write_domain != I915_GEM_DOMAIN_GTT)
		return;

	/* No actual flushing is required for the GTT write domain.  Writes
	 * to it immediately go to main memory as far as we know, so there's
	 * no chipset flush.  It also doesn't land in render cache.
	 *
	 * However, we do have to enforce the order so that all writes through
	 * the GTT land before any writes to the device, such as updates to
	 * the GATT itself.
	 */
	wmb();

	old_write_domain = obj->base.write_domain;
	obj->base.write_domain = 0;

	intel_fb_obj_flush(obj, false);

	trace_i915_gem_object_change_domain(obj,
					    obj->base.read_domains,
					    old_write_domain);
}

/** Flushes the CPU write domain for the object if it's dirty. */
static void
i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj,
				       bool force)
{
	uint32_t old_write_domain;

	if (obj->base.write_domain != I915_GEM_DOMAIN_CPU)
		return;

	if (i915_gem_clflush_object(obj, force))
		i915_gem_chipset_flush(obj->base.dev);

	old_write_domain = obj->base.write_domain;
	obj->base.write_domain = 0;

	intel_fb_obj_flush(obj, false);

	trace_i915_gem_object_change_domain(obj,
					    obj->base.read_domains,
					    old_write_domain);
}

/**
 * Moves a single object to the GTT read, and possibly write domain.
 *
 * This function returns when the move is complete, including waiting on
 * flushes to occur.
 */
int
i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	struct i915_vma *vma = i915_gem_obj_to_ggtt(obj);
	uint32_t old_write_domain, old_read_domains;
	int ret;

	/* Not valid to be called on unbound objects. */
	if (vma == NULL)
		return -EINVAL;

	if (obj->base.write_domain == I915_GEM_DOMAIN_GTT)
		return 0;

	ret = i915_gem_object_wait_rendering(obj, !write);
	if (ret)
		return ret;

	i915_gem_object_retire(obj);
	i915_gem_object_flush_cpu_write_domain(obj, false);

	/* Serialise direct access to this object with the barriers for
	 * coherent writes from the GPU, by effectively invalidating the
	 * GTT domain upon first access.
	 */
	if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
		mb();

	old_write_domain = obj->base.write_domain;
	old_read_domains = obj->base.read_domains;

	/* It should now be out of any other write domains, and we can update
	 * the domain values for our changes.
	 */
	BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_GTT) != 0);
	obj->base.read_domains |= I915_GEM_DOMAIN_GTT;
	if (write) {
		obj->base.read_domains = I915_GEM_DOMAIN_GTT;
		obj->base.write_domain = I915_GEM_DOMAIN_GTT;
		obj->dirty = 1;
	}

	if (write)
		intel_fb_obj_invalidate(obj, NULL);

	trace_i915_gem_object_change_domain(obj,
					    old_read_domains,
					    old_write_domain);

	/* And bump the LRU for this access */
	if (i915_gem_object_is_inactive(obj))
		list_move_tail(&vma->mm_list,
			       &dev_priv->gtt.base.inactive_list);

	return 0;
}

int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
				    enum i915_cache_level cache_level)
{
	struct drm_device *dev = obj->base.dev;
	struct i915_vma *vma, *next;
	int ret;

	if (obj->cache_level == cache_level)
		return 0;

	if (i915_gem_obj_is_pinned(obj)) {
		DRM_DEBUG("can not change the cache level of pinned objects\n");
		return -EBUSY;
	}

	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link) {
		if (!i915_gem_valid_gtt_space(vma, cache_level)) {
			ret = i915_vma_unbind(vma);
			if (ret)
				return ret;
		}
	}

	if (i915_gem_obj_bound_any(obj)) {
		ret = i915_gem_object_finish_gpu(obj);
		if (ret)
			return ret;

		i915_gem_object_finish_gtt(obj);

		/* Before SandyBridge, you could not use tiling or fence
		 * registers with snooped memory, so relinquish any fences
		 * currently pointing to our region in the aperture.
		 */
		if (INTEL_INFO(dev)->gen < 6) {
			ret = i915_gem_object_put_fence(obj);
			if (ret)
				return ret;
		}

		list_for_each_entry(vma, &obj->vma_list, vma_link)
			if (drm_mm_node_allocated(&vma->node))
				vma->bind_vma(vma, cache_level,
						vma->bound & GLOBAL_BIND);
	}

	list_for_each_entry(vma, &obj->vma_list, vma_link)
		vma->node.color = cache_level;
	obj->cache_level = cache_level;

	if (cpu_write_needs_clflush(obj)) {
		u32 old_read_domains, old_write_domain;

		/* If we're coming from LLC cached, then we haven't
		 * actually been tracking whether the data is in the
		 * CPU cache or not, since we only allow one bit set
		 * in obj->write_domain and have been skipping the clflushes.
		 * Just set it to the CPU cache for now.
		 */
		i915_gem_object_retire(obj);
		WARN_ON(obj->base.write_domain & ~I915_GEM_DOMAIN_CPU);

		old_read_domains = obj->base.read_domains;
		old_write_domain = obj->base.write_domain;

		obj->base.read_domains = I915_GEM_DOMAIN_CPU;
		obj->base.write_domain = I915_GEM_DOMAIN_CPU;

		trace_i915_gem_object_change_domain(obj,
						    old_read_domains,
						    old_write_domain);
	}

	return 0;
}

int i915_gem_get_caching_ioctl(struct drm_device *dev, void *data,
			       struct drm_file *file)
{
	struct drm_i915_gem_caching *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	switch (obj->cache_level) {
	case I915_CACHE_LLC:
	case I915_CACHE_L3_LLC:
		args->caching = I915_CACHING_CACHED;
		break;

	case I915_CACHE_WT:
		args->caching = I915_CACHING_DISPLAY;
		break;

	default:
		args->caching = I915_CACHING_NONE;
		break;
	}

	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int i915_gem_set_caching_ioctl(struct drm_device *dev, void *data,
			       struct drm_file *file)
{
	struct drm_i915_gem_caching *args = data;
	struct drm_i915_gem_object *obj;
	enum i915_cache_level level;
	int ret;

	switch (args->caching) {
	case I915_CACHING_NONE:
		level = I915_CACHE_NONE;
		break;
	case I915_CACHING_CACHED:
		level = I915_CACHE_LLC;
		break;
	case I915_CACHING_DISPLAY:
		level = HAS_WT(dev) ? I915_CACHE_WT : I915_CACHE_NONE;
		break;
	default:
		return -EINVAL;
	}

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	ret = i915_gem_object_set_cache_level(obj, level);

	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

static bool is_pin_display(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma;

	vma = i915_gem_obj_to_ggtt(obj);
	if (!vma)
		return false;

	/* There are 3 sources that pin objects:
	 *   1. The display engine (scanouts, sprites, cursors);
	 *   2. Reservations for execbuffer;
	 *   3. The user.
	 *
	 * We can ignore reservations as we hold the struct_mutex and
	 * are only called outside of the reservation path.  The user
	 * can only increment pin_count once, and so if after
	 * subtracting the potential reference by the user, any pin_count
	 * remains, it must be due to another use by the display engine.
	 */
	return vma->pin_count - !!obj->user_pin_count;
}

/*
 * Prepare buffer for display plane (scanout, cursors, etc).
 * Can be called from an uninterruptible phase (modesetting) and allows
 * any flushes to be pipelined (for pageflips).
 */
int
i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
				     u32 alignment,
				     struct intel_engine_cs *pipelined)
{
	u32 old_read_domains, old_write_domain;
	bool was_pin_display;
	int ret;

	if (pipelined != obj->ring) {
		ret = i915_gem_object_sync(obj, pipelined);
		if (ret)
			return ret;
	}

	/* Mark the pin_display early so that we account for the
	 * display coherency whilst setting up the cache domains.
	 */
	was_pin_display = obj->pin_display;
	obj->pin_display = true;

	/* The display engine is not coherent with the LLC cache on gen6.  As
	 * a result, we make sure that the pinning that is about to occur is
	 * done with uncached PTEs. This is lowest common denominator for all
	 * chipsets.
	 *
	 * However for gen6+, we could do better by using the GFDT bit instead
	 * of uncaching, which would allow us to flush all the LLC-cached data
	 * with that bit in the PTE to main memory with just one PIPE_CONTROL.
	 */
	ret = i915_gem_object_set_cache_level(obj,
					      HAS_WT(obj->base.dev) ? I915_CACHE_WT : I915_CACHE_NONE);
	if (ret)
		goto err_unpin_display;

	/* As the user may map the buffer once pinned in the display plane
	 * (e.g. libkms for the bootup splash), we have to ensure that we
	 * always use map_and_fenceable for all scanout buffers.
	 */
	ret = i915_gem_obj_ggtt_pin(obj, alignment, PIN_MAPPABLE);
	if (ret)
		goto err_unpin_display;

	i915_gem_object_flush_cpu_write_domain(obj, true);

	old_write_domain = obj->base.write_domain;
	old_read_domains = obj->base.read_domains;

	/* It should now be out of any other write domains, and we can update
	 * the domain values for our changes.
	 */
	obj->base.write_domain = 0;
	obj->base.read_domains |= I915_GEM_DOMAIN_GTT;

	trace_i915_gem_object_change_domain(obj,
					    old_read_domains,
					    old_write_domain);

	return 0;

err_unpin_display:
	WARN_ON(was_pin_display != is_pin_display(obj));
	obj->pin_display = was_pin_display;
	return ret;
}

void
i915_gem_object_unpin_from_display_plane(struct drm_i915_gem_object *obj)
{
	i915_gem_object_ggtt_unpin(obj);
	obj->pin_display = is_pin_display(obj);
}

int
i915_gem_object_finish_gpu(struct drm_i915_gem_object *obj)
{
	int ret;

	if ((obj->base.read_domains & I915_GEM_GPU_DOMAINS) == 0)
		return 0;

	ret = i915_gem_object_wait_rendering(obj, false);
	if (ret)
		return ret;

	/* Ensure that we invalidate the GPU's caches and TLBs. */
	obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS;
	return 0;
}

/**
 * Moves a single object to the CPU read, and possibly write domain.
 *
 * This function returns when the move is complete, including waiting on
 * flushes to occur.
 */
int
i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
{
	uint32_t old_write_domain, old_read_domains;
	int ret;

	if (obj->base.write_domain == I915_GEM_DOMAIN_CPU)
		return 0;

	ret = i915_gem_object_wait_rendering(obj, !write);
	if (ret)
		return ret;

	i915_gem_object_retire(obj);
	i915_gem_object_flush_gtt_write_domain(obj);

	old_write_domain = obj->base.write_domain;
	old_read_domains = obj->base.read_domains;

	/* Flush the CPU cache if it's still invalid. */
	if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) {
		i915_gem_clflush_object(obj, false);

		obj->base.read_domains |= I915_GEM_DOMAIN_CPU;
	}

	/* It should now be out of any other write domains, and we can update
	 * the domain values for our changes.
	 */
	BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_CPU) != 0);

	/* If we're writing through the CPU, then the GPU read domains will
	 * need to be invalidated at next use.
	 */
	if (write) {
		obj->base.read_domains = I915_GEM_DOMAIN_CPU;
		obj->base.write_domain = I915_GEM_DOMAIN_CPU;
	}

	if (write)
		intel_fb_obj_invalidate(obj, NULL);

	trace_i915_gem_object_change_domain(obj,
					    old_read_domains,
					    old_write_domain);

	return 0;
}

/* Throttle our rendering by waiting until the ring has completed our requests
 * emitted over 20 msec ago.
 *
 * Note that if we were to use the current jiffies each time around the loop,
 * we wouldn't escape the function with any frames outstanding if the time to
 * render a frame was over 20ms.
 *
 * This should get us reasonable parallelism between CPU and GPU but also
 * relatively low latency when blocking on a particular request to finish.
 */
static int
i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_file_private *file_priv = file->driver_priv;
	unsigned long recent_enough = jiffies - msecs_to_jiffies(20);
	struct drm_i915_gem_request *request;
	struct intel_engine_cs *ring = NULL;
	unsigned reset_counter;
	u32 seqno = 0;
	int ret;

	ret = i915_gem_wait_for_error(&dev_priv->gpu_error);
	if (ret)
		return ret;

	ret = i915_gem_check_wedge(&dev_priv->gpu_error, false);
	if (ret)
		return ret;

	spin_lock(&file_priv->mm.lock);
	list_for_each_entry(request, &file_priv->mm.request_list, client_list) {
		if (time_after_eq(request->emitted_jiffies, recent_enough))
			break;

		ring = request->ring;
		seqno = request->seqno;
	}
	reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter);
	spin_unlock(&file_priv->mm.lock);

	if (seqno == 0)
		return 0;

	ret = __i915_wait_seqno(ring, seqno, reset_counter, true, NULL, NULL);
	if (ret == 0)
		queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, 0);

	return ret;
}

static bool
i915_vma_misplaced(struct i915_vma *vma, uint32_t alignment, uint64_t flags)
{
	struct drm_i915_gem_object *obj = vma->obj;

	if (alignment &&
	    vma->node.start & (alignment - 1))
		return true;

	if (flags & PIN_MAPPABLE && !obj->map_and_fenceable)
		return true;

	if (flags & PIN_OFFSET_BIAS &&
	    vma->node.start < (flags & PIN_OFFSET_MASK))
		return true;

	return false;
}

int
i915_gem_object_pin(struct drm_i915_gem_object *obj,
		    struct i915_address_space *vm,
		    uint32_t alignment,
		    uint64_t flags)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
	struct i915_vma *vma;
	unsigned bound;
	int ret;

	if (WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base))
		return -ENODEV;

	if (WARN_ON(flags & (PIN_GLOBAL | PIN_MAPPABLE) && !i915_is_ggtt(vm)))
		return -EINVAL;

	if (WARN_ON((flags & (PIN_MAPPABLE | PIN_GLOBAL)) == PIN_MAPPABLE))
		return -EINVAL;

	vma = i915_gem_obj_to_vma(obj, vm);
	if (vma) {
		if (WARN_ON(vma->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT))
			return -EBUSY;

		if (i915_vma_misplaced(vma, alignment, flags)) {
			WARN(vma->pin_count,
			     "bo is already pinned with incorrect alignment:"
			     " offset=%lx, req.alignment=%x, req.map_and_fenceable=%d,"
			     " obj->map_and_fenceable=%d\n",
			     i915_gem_obj_offset(obj, vm), alignment,
			     !!(flags & PIN_MAPPABLE),
			     obj->map_and_fenceable);
			ret = i915_vma_unbind(vma);
			if (ret)
				return ret;

			vma = NULL;
		}
	}

	bound = vma ? vma->bound : 0;
	if (vma == NULL || !drm_mm_node_allocated(&vma->node)) {
		vma = i915_gem_object_bind_to_vm(obj, vm, alignment, flags);
		if (IS_ERR(vma))
			return PTR_ERR(vma);
	}

	if (flags & PIN_GLOBAL && !(vma->bound & GLOBAL_BIND))
		vma->bind_vma(vma, obj->cache_level, GLOBAL_BIND);

	if ((bound ^ vma->bound) & GLOBAL_BIND) {
		bool mappable, fenceable;
		u32 fence_size, fence_alignment;

		fence_size = i915_gem_get_gtt_size(obj->base.dev,
						   obj->base.size,
						   obj->tiling_mode);
		fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
							     obj->base.size,
							     obj->tiling_mode,
							     true);

		fenceable = (vma->node.size == fence_size &&
			     (vma->node.start & (fence_alignment - 1)) == 0);

		mappable = (vma->node.start + obj->base.size <=
			    dev_priv->gtt.mappable_end);

		obj->map_and_fenceable = mappable && fenceable;
	}

	WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);

	vma->pin_count++;
	if (flags & PIN_MAPPABLE)
		obj->pin_mappable |= true;

	return 0;
}

void
i915_gem_object_ggtt_unpin(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma = i915_gem_obj_to_ggtt(obj);

	BUG_ON(!vma);
	BUG_ON(vma->pin_count == 0);
	BUG_ON(!i915_gem_obj_ggtt_bound(obj));

	if (--vma->pin_count == 0)
		obj->pin_mappable = false;
}

bool
i915_gem_object_pin_fence(struct drm_i915_gem_object *obj)
{
	if (obj->fence_reg != I915_FENCE_REG_NONE) {
		struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
		struct i915_vma *ggtt_vma = i915_gem_obj_to_ggtt(obj);

		WARN_ON(!ggtt_vma ||
			dev_priv->fence_regs[obj->fence_reg].pin_count >
			ggtt_vma->pin_count);
		dev_priv->fence_regs[obj->fence_reg].pin_count++;
		return true;
	} else
		return false;
}

void
i915_gem_object_unpin_fence(struct drm_i915_gem_object *obj)
{
	if (obj->fence_reg != I915_FENCE_REG_NONE) {
		struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
		WARN_ON(dev_priv->fence_regs[obj->fence_reg].pin_count <= 0);
		dev_priv->fence_regs[obj->fence_reg].pin_count--;
	}
}

int
i915_gem_pin_ioctl(struct drm_device *dev, void *data,
		   struct drm_file *file)
{
	struct drm_i915_gem_pin *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	if (drm_core_check_feature(dev, DRIVER_MODESET))
		return -ENODEV;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	if (obj->madv != I915_MADV_WILLNEED) {
		DRM_DEBUG("Attempting to pin a purgeable buffer\n");
		ret = -EFAULT;
		goto out;
	}

	if (obj->pin_filp != NULL && obj->pin_filp != file) {
		DRM_DEBUG("Already pinned in i915_gem_pin_ioctl(): %d\n",
			  args->handle);
		ret = -EINVAL;
		goto out;
	}

	if (obj->user_pin_count == ULONG_MAX) {
		ret = -EBUSY;
		goto out;
	}

	if (obj->user_pin_count == 0) {
		ret = i915_gem_obj_ggtt_pin(obj, args->alignment, PIN_MAPPABLE);
		if (ret)
			goto out;
	}

	obj->user_pin_count++;
	obj->pin_filp = file;

	args->offset = i915_gem_obj_ggtt_offset(obj);
out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int
i915_gem_unpin_ioctl(struct drm_device *dev, void *data,
		     struct drm_file *file)
{
	struct drm_i915_gem_pin *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	if (drm_core_check_feature(dev, DRIVER_MODESET))
		return -ENODEV;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	if (obj->pin_filp != file) {
		DRM_DEBUG("Not pinned by caller in i915_gem_pin_ioctl(): %d\n",
			  args->handle);
		ret = -EINVAL;
		goto out;
	}
	obj->user_pin_count--;
	if (obj->user_pin_count == 0) {
		obj->pin_filp = NULL;
		i915_gem_object_ggtt_unpin(obj);
	}

out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int
i915_gem_busy_ioctl(struct drm_device *dev, void *data,
		    struct drm_file *file)
{
	struct drm_i915_gem_busy *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	/* Count all active objects as busy, even if they are currently not used
	 * by the gpu. Users of this interface expect objects to eventually
	 * become non-busy without any further actions, therefore emit any
	 * necessary flushes here.
	 */
	ret = i915_gem_object_flush_active(obj);

	args->busy = obj->active;
	if (obj->ring) {
		BUILD_BUG_ON(I915_NUM_RINGS > 16);
		args->busy |= intel_ring_flag(obj->ring) << 16;
	}

	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int
i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
			struct drm_file *file_priv)
{
	return i915_gem_ring_throttle(dev, file_priv);
}

int
i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
		       struct drm_file *file_priv)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_madvise *args = data;
	struct drm_i915_gem_object *obj;
	int ret;

	switch (args->madv) {
	case I915_MADV_DONTNEED:
	case I915_MADV_WILLNEED:
	    break;
	default:
	    return -EINVAL;
	}

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	obj = to_intel_bo(drm_gem_object_lookup(dev, file_priv, args->handle));
	if (&obj->base == NULL) {
		ret = -ENOENT;
		goto unlock;
	}

	if (i915_gem_obj_is_pinned(obj)) {
		ret = -EINVAL;
		goto out;
	}

	if (obj->pages &&
	    obj->tiling_mode != I915_TILING_NONE &&
	    dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
		if (obj->madv == I915_MADV_WILLNEED)
			i915_gem_object_unpin_pages(obj);
		if (args->madv == I915_MADV_WILLNEED)
			i915_gem_object_pin_pages(obj);
	}

	if (obj->madv != __I915_MADV_PURGED)
		obj->madv = args->madv;

	/* if the object is no longer attached, discard its backing storage */
	if (i915_gem_object_is_purgeable(obj) && obj->pages == NULL)
		i915_gem_object_truncate(obj);

	args->retained = obj->madv != __I915_MADV_PURGED;

out:
	drm_gem_object_unreference(&obj->base);
unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

void i915_gem_object_init(struct drm_i915_gem_object *obj,
			  const struct drm_i915_gem_object_ops *ops)
{
	INIT_LIST_HEAD(&obj->global_list);
	INIT_LIST_HEAD(&obj->ring_list);
	INIT_LIST_HEAD(&obj->obj_exec_link);
	INIT_LIST_HEAD(&obj->vma_list);

	obj->ops = ops;

	obj->fence_reg = I915_FENCE_REG_NONE;
	obj->madv = I915_MADV_WILLNEED;

	i915_gem_info_add_obj(obj->base.dev->dev_private, obj->base.size);
}

static const struct drm_i915_gem_object_ops i915_gem_object_ops = {
	.get_pages = i915_gem_object_get_pages_gtt,
	.put_pages = i915_gem_object_put_pages_gtt,
};

struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
						  size_t size)
{
	struct drm_i915_gem_object *obj;
	struct address_space *mapping;
	gfp_t mask;

	obj = i915_gem_object_alloc(dev);
	if (obj == NULL)
		return NULL;

	if (drm_gem_object_init(dev, &obj->base, size) != 0) {
		i915_gem_object_free(obj);
		return NULL;
	}

	mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
	if (IS_CRESTLINE(dev) || IS_BROADWATER(dev)) {
		/* 965gm cannot relocate objects above 4GiB. */
		mask &= ~__GFP_HIGHMEM;
		mask |= __GFP_DMA32;
	}

	mapping = file_inode(obj->base.filp)->i_mapping;
	mapping_set_gfp_mask(mapping, mask);

	i915_gem_object_init(obj, &i915_gem_object_ops);

	obj->base.write_domain = I915_GEM_DOMAIN_CPU;
	obj->base.read_domains = I915_GEM_DOMAIN_CPU;

	if (HAS_LLC(dev)) {
		/* On some devices, we can have the GPU use the LLC (the CPU
		 * cache) for about a 10% performance improvement
		 * compared to uncached.  Graphics requests other than
		 * display scanout are coherent with the CPU in
		 * accessing this cache.  This means in this mode we
		 * don't need to clflush on the CPU side, and on the
		 * GPU side we only need to flush internal caches to
		 * get data visible to the CPU.
		 *
		 * However, we maintain the display planes as UC, and so
		 * need to rebind when first used as such.
		 */
		obj->cache_level = I915_CACHE_LLC;
	} else
		obj->cache_level = I915_CACHE_NONE;

	trace_i915_gem_object_create(obj);

	return obj;
}

static bool discard_backing_storage(struct drm_i915_gem_object *obj)
{
	/* If we are the last user of the backing storage (be it shmemfs
	 * pages or stolen etc), we know that the pages are going to be
	 * immediately released. In this case, we can then skip copying
	 * back the contents from the GPU.
	 */

	if (obj->madv != I915_MADV_WILLNEED)
		return false;

	if (obj->base.filp == NULL)
		return true;

	/* At first glance, this looks racy, but then again so would be
	 * userspace racing mmap against close. However, the first external
	 * reference to the filp can only be obtained through the
	 * i915_gem_mmap_ioctl() which safeguards us against the user
	 * acquiring such a reference whilst we are in the middle of
	 * freeing the object.
	 */
	return atomic_long_read(&obj->base.filp->f_count) == 1;
}

void i915_gem_free_object(struct drm_gem_object *gem_obj)
{
	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct i915_vma *vma, *next;

	intel_runtime_pm_get(dev_priv);

	trace_i915_gem_object_destroy(obj);

	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link) {
		int ret;

		vma->pin_count = 0;
		ret = i915_vma_unbind(vma);
		if (WARN_ON(ret == -ERESTARTSYS)) {
			bool was_interruptible;

			was_interruptible = dev_priv->mm.interruptible;
			dev_priv->mm.interruptible = false;

			WARN_ON(i915_vma_unbind(vma));

			dev_priv->mm.interruptible = was_interruptible;
		}
	}

	/* Stolen objects don't hold a ref, but do hold pin count. Fix that up
	 * before progressing. */
	if (obj->stolen)
		i915_gem_object_unpin_pages(obj);

	WARN_ON(obj->frontbuffer_bits);

	if (obj->pages && obj->madv == I915_MADV_WILLNEED &&
	    dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES &&
	    obj->tiling_mode != I915_TILING_NONE)
		i915_gem_object_unpin_pages(obj);

	if (WARN_ON(obj->pages_pin_count))
		obj->pages_pin_count = 0;
	if (discard_backing_storage(obj))
		obj->madv = I915_MADV_DONTNEED;
	i915_gem_object_put_pages(obj);
	i915_gem_object_free_mmap_offset(obj);

	BUG_ON(obj->pages);

	if (obj->base.import_attach)
		drm_prime_gem_destroy(&obj->base, NULL);

	if (obj->ops->release)
		obj->ops->release(obj);

	drm_gem_object_release(&obj->base);
	i915_gem_info_remove_obj(dev_priv, obj->base.size);

	kfree(obj->bit_17);
	i915_gem_object_free(obj);

	intel_runtime_pm_put(dev_priv);
}

struct i915_vma *i915_gem_obj_to_vma(struct drm_i915_gem_object *obj,
				     struct i915_address_space *vm)
{
	struct i915_vma *vma;
	list_for_each_entry(vma, &obj->vma_list, vma_link)
		if (vma->vm == vm)
			return vma;

	return NULL;
}

void i915_gem_vma_destroy(struct i915_vma *vma)
{
	struct i915_address_space *vm = NULL;
	WARN_ON(vma->node.allocated);

	/* Keep the vma as a placeholder in the execbuffer reservation lists */
	if (!list_empty(&vma->exec_list))
		return;

	vm = vma->vm;

	if (!i915_is_ggtt(vm))
		i915_ppgtt_put(i915_vm_to_ppgtt(vm));

	list_del(&vma->vma_link);

	kfree(vma);
}

static void
i915_gem_stop_ringbuffers(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int i;

	for_each_ring(ring, dev_priv, i)
		dev_priv->gt.stop_ring(ring);
}

int
i915_gem_suspend(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret = 0;

	mutex_lock(&dev->struct_mutex);
	ret = i915_gpu_idle(dev);
	if (ret)
		goto err;

	i915_gem_retire_requests(dev);

	/* Under UMS, be paranoid and evict. */
	if (!drm_core_check_feature(dev, DRIVER_MODESET))
		i915_gem_evict_everything(dev);

	i915_gem_stop_ringbuffers(dev);
	mutex_unlock(&dev->struct_mutex);

	del_timer_sync(&dev_priv->gpu_error.hangcheck_timer);
	cancel_delayed_work_sync(&dev_priv->mm.retire_work);
	flush_delayed_work(&dev_priv->mm.idle_work);

	return 0;

err:
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int i915_gem_l3_remap(struct intel_engine_cs *ring, int slice)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 reg_base = GEN7_L3LOG_BASE + (slice * 0x200);
	u32 *remap_info = dev_priv->l3_parity.remap_info[slice];
	int i, ret;

	if (!HAS_L3_DPF(dev) || !remap_info)
		return 0;

	ret = intel_ring_begin(ring, GEN7_L3LOG_SIZE / 4 * 3);
	if (ret)
		return ret;

	/*
	 * Note: We do not worry about the concurrent register cacheline hang
	 * here because no other code should access these registers other than
	 * at initialization time.
	 */
	for (i = 0; i < GEN7_L3LOG_SIZE; i += 4) {
		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
		intel_ring_emit(ring, reg_base + i);
		intel_ring_emit(ring, remap_info[i/4]);
	}

	intel_ring_advance(ring);

	return ret;
}

void i915_gem_init_swizzling(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (INTEL_INFO(dev)->gen < 5 ||
	    dev_priv->mm.bit_6_swizzle_x == I915_BIT_6_SWIZZLE_NONE)
		return;

	I915_WRITE(DISP_ARB_CTL, I915_READ(DISP_ARB_CTL) |
				 DISP_TILE_SURFACE_SWIZZLING);

	if (IS_GEN5(dev))
		return;

	I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_SWZCTL);
	if (IS_GEN6(dev))
		I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_SNB));
	else if (IS_GEN7(dev))
		I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_IVB));
	else if (IS_GEN8(dev))
		I915_WRITE(GAMTARBMODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_BDW));
	else
		BUG();
}

static bool
intel_enable_blt(struct drm_device *dev)
{
	if (!HAS_BLT(dev))
		return false;

	/* The blitter was dysfunctional on early prototypes */
	if (IS_GEN6(dev) && dev->pdev->revision < 8) {
		DRM_INFO("BLT not supported on this pre-production hardware;"
			 " graphics performance will be degraded.\n");
		return false;
	}

	return true;
}

static void init_unused_ring(struct drm_device *dev, u32 base)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(RING_CTL(base), 0);
	I915_WRITE(RING_HEAD(base), 0);
	I915_WRITE(RING_TAIL(base), 0);
	I915_WRITE(RING_START(base), 0);
}

static void init_unused_rings(struct drm_device *dev)
{
	if (IS_I830(dev)) {
		init_unused_ring(dev, PRB1_BASE);
		init_unused_ring(dev, SRB0_BASE);
		init_unused_ring(dev, SRB1_BASE);
		init_unused_ring(dev, SRB2_BASE);
		init_unused_ring(dev, SRB3_BASE);
	} else if (IS_GEN2(dev)) {
		init_unused_ring(dev, SRB0_BASE);
		init_unused_ring(dev, SRB1_BASE);
	} else if (IS_GEN3(dev)) {
		init_unused_ring(dev, PRB1_BASE);
		init_unused_ring(dev, PRB2_BASE);
	}
}

int i915_gem_init_rings(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	/*
	 * At least 830 can leave some of the unused rings
	 * "active" (ie. head != tail) after resume which
	 * will prevent c3 entry. Makes sure all unused rings
	 * are totally idle.
	 */
	init_unused_rings(dev);

	ret = intel_init_render_ring_buffer(dev);
	if (ret)
		return ret;

	if (HAS_BSD(dev)) {
		ret = intel_init_bsd_ring_buffer(dev);
		if (ret)
			goto cleanup_render_ring;
	}

	if (intel_enable_blt(dev)) {
		ret = intel_init_blt_ring_buffer(dev);
		if (ret)
			goto cleanup_bsd_ring;
	}

	if (HAS_VEBOX(dev)) {
		ret = intel_init_vebox_ring_buffer(dev);
		if (ret)
			goto cleanup_blt_ring;
	}

	if (HAS_BSD2(dev)) {
		ret = intel_init_bsd2_ring_buffer(dev);
		if (ret)
			goto cleanup_vebox_ring;
	}

	ret = i915_gem_set_seqno(dev, ((u32)~0 - 0x1000));
	if (ret)
		goto cleanup_bsd2_ring;

	return 0;

cleanup_bsd2_ring:
	intel_cleanup_ring_buffer(&dev_priv->ring[VCS2]);
cleanup_vebox_ring:
	intel_cleanup_ring_buffer(&dev_priv->ring[VECS]);
cleanup_blt_ring:
	intel_cleanup_ring_buffer(&dev_priv->ring[BCS]);
cleanup_bsd_ring:
	intel_cleanup_ring_buffer(&dev_priv->ring[VCS]);
cleanup_render_ring:
	intel_cleanup_ring_buffer(&dev_priv->ring[RCS]);

	return ret;
}

int
i915_gem_init_hw(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret, i;

	if (INTEL_INFO(dev)->gen < 6 && !intel_enable_gtt())
		return -EIO;

	if (dev_priv->ellc_size)
		I915_WRITE(HSW_IDICR, I915_READ(HSW_IDICR) | IDIHASHMSK(0xf));

	if (IS_HASWELL(dev))
		I915_WRITE(MI_PREDICATE_RESULT_2, IS_HSW_GT3(dev) ?
			   LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED);

	if (HAS_PCH_NOP(dev)) {
		if (IS_IVYBRIDGE(dev)) {
			u32 temp = I915_READ(GEN7_MSG_CTL);
			temp &= ~(WAIT_FOR_PCH_FLR_ACK | WAIT_FOR_PCH_RESET_ACK);
			I915_WRITE(GEN7_MSG_CTL, temp);
		} else if (INTEL_INFO(dev)->gen >= 7) {
			u32 temp = I915_READ(HSW_NDE_RSTWRN_OPT);
			temp &= ~RESET_PCH_HANDSHAKE_ENABLE;
			I915_WRITE(HSW_NDE_RSTWRN_OPT, temp);
		}
	}

	i915_gem_init_swizzling(dev);

	ret = dev_priv->gt.init_rings(dev);
	if (ret)
		return ret;

	for (i = 0; i < NUM_L3_SLICES(dev); i++)
		i915_gem_l3_remap(&dev_priv->ring[RCS], i);

	ret = i915_ppgtt_init_hw(dev);
	if (ret && ret != -EIO) {
		DRM_ERROR("PPGTT enable failed %d\n", ret);
		i915_gem_cleanup_ringbuffer(dev);
	}

	ret = i915_gem_context_enable(dev_priv);
	if (ret && ret != -EIO) {
		DRM_ERROR("Context enable failed %d\n", ret);
		i915_gem_cleanup_ringbuffer(dev);

		return ret;
	}

	return ret;
}

int i915_gem_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	i915.enable_execlists = intel_sanitize_enable_execlists(dev,
			i915.enable_execlists);

	mutex_lock(&dev->struct_mutex);

	if (IS_VALLEYVIEW(dev)) {
		/* VLVA0 (potential hack), BIOS isn't actually waking us */
		I915_WRITE(VLV_GTLC_WAKE_CTRL, VLV_GTLC_ALLOWWAKEREQ);
		if (wait_for((I915_READ(VLV_GTLC_PW_STATUS) &
			      VLV_GTLC_ALLOWWAKEACK), 10))
			DRM_DEBUG_DRIVER("allow wake ack timed out\n");
	}

	if (!i915.enable_execlists) {
		dev_priv->gt.do_execbuf = i915_gem_ringbuffer_submission;
		dev_priv->gt.init_rings = i915_gem_init_rings;
		dev_priv->gt.cleanup_ring = intel_cleanup_ring_buffer;
		dev_priv->gt.stop_ring = intel_stop_ring_buffer;
	} else {
		dev_priv->gt.do_execbuf = intel_execlists_submission;
		dev_priv->gt.init_rings = intel_logical_rings_init;
		dev_priv->gt.cleanup_ring = intel_logical_ring_cleanup;
		dev_priv->gt.stop_ring = intel_logical_ring_stop;
	}

	ret = i915_gem_init_userptr(dev);
	if (ret) {
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	i915_gem_init_global_gtt(dev);

	ret = i915_gem_context_init(dev);
	if (ret) {
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	ret = i915_gem_init_hw(dev);
	if (ret == -EIO) {
		/* Allow ring initialisation to fail by marking the GPU as
		 * wedged. But we only want to do this where the GPU is angry,
		 * for all other failure, such as an allocation failure, bail.
		 */
		DRM_ERROR("Failed to initialize GPU, declaring it wedged\n");
		atomic_set_mask(I915_WEDGED, &dev_priv->gpu_error.reset_counter);
		ret = 0;
	}
	mutex_unlock(&dev->struct_mutex);

	return ret;
}

void
i915_gem_cleanup_ringbuffer(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int i;

	for_each_ring(ring, dev_priv, i)
		dev_priv->gt.cleanup_ring(ring);
}

static void
init_ring_lists(struct intel_engine_cs *ring)
{
	INIT_LIST_HEAD(&ring->active_list);
	INIT_LIST_HEAD(&ring->request_list);
}

void i915_init_vm(struct drm_i915_private *dev_priv,
		  struct i915_address_space *vm)
{
	if (!i915_is_ggtt(vm))
		drm_mm_init(&vm->mm, vm->start, vm->total);
	vm->dev = dev_priv->dev;
	INIT_LIST_HEAD(&vm->active_list);
	INIT_LIST_HEAD(&vm->inactive_list);
	INIT_LIST_HEAD(&vm->global_link);
	list_add_tail(&vm->global_link, &dev_priv->vm_list);
}

void
i915_gem_load(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int i;

	dev_priv->slab =
		kmem_cache_create("i915_gem_object",
				  sizeof(struct drm_i915_gem_object), 0,
				  SLAB_HWCACHE_ALIGN,
				  NULL);

	INIT_LIST_HEAD(&dev_priv->vm_list);
	i915_init_vm(dev_priv, &dev_priv->gtt.base);

	INIT_LIST_HEAD(&dev_priv->context_list);
	INIT_LIST_HEAD(&dev_priv->mm.unbound_list);
	INIT_LIST_HEAD(&dev_priv->mm.bound_list);
	INIT_LIST_HEAD(&dev_priv->mm.fence_list);
	for (i = 0; i < I915_NUM_RINGS; i++)
		init_ring_lists(&dev_priv->ring[i]);
	for (i = 0; i < I915_MAX_NUM_FENCES; i++)
		INIT_LIST_HEAD(&dev_priv->fence_regs[i].lru_list);
	INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
			  i915_gem_retire_work_handler);
	INIT_DELAYED_WORK(&dev_priv->mm.idle_work,
			  i915_gem_idle_work_handler);
	init_waitqueue_head(&dev_priv->gpu_error.reset_queue);

	/* On GEN3 we really need to make sure the ARB C3 LP bit is set */
	if (!drm_core_check_feature(dev, DRIVER_MODESET) && IS_GEN3(dev)) {
		I915_WRITE(MI_ARB_STATE,
			   _MASKED_BIT_ENABLE(MI_ARB_C3_LP_WRITE_ENABLE));
	}

	dev_priv->relative_constants_mode = I915_EXEC_CONSTANTS_REL_GENERAL;

	/* Old X drivers will take 0-2 for front, back, depth buffers */
	if (!drm_core_check_feature(dev, DRIVER_MODESET))
		dev_priv->fence_reg_start = 3;

	if (INTEL_INFO(dev)->gen >= 7 && !IS_VALLEYVIEW(dev))
		dev_priv->num_fence_regs = 32;
	else if (INTEL_INFO(dev)->gen >= 4 || IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
		dev_priv->num_fence_regs = 16;
	else
		dev_priv->num_fence_regs = 8;

	/* Initialize fence registers to zero */
	INIT_LIST_HEAD(&dev_priv->mm.fence_list);
	i915_gem_restore_fences(dev);

	i915_gem_detect_bit_6_swizzle(dev);
	init_waitqueue_head(&dev_priv->pending_flip_queue);

	dev_priv->mm.interruptible = true;

	dev_priv->mm.shrinker.scan_objects = i915_gem_shrinker_scan;
	dev_priv->mm.shrinker.count_objects = i915_gem_shrinker_count;
	dev_priv->mm.shrinker.seeks = DEFAULT_SEEKS;
	register_shrinker(&dev_priv->mm.shrinker);

	dev_priv->mm.oom_notifier.notifier_call = i915_gem_shrinker_oom;
	register_oom_notifier(&dev_priv->mm.oom_notifier);

	mutex_init(&dev_priv->fb_tracking.lock);
}

void i915_gem_release(struct drm_device *dev, struct drm_file *file)
{
	struct drm_i915_file_private *file_priv = file->driver_priv;

	cancel_delayed_work_sync(&file_priv->mm.idle_work);

	/* Clean up our request list when the client is going away, so that
	 * later retire_requests won't dereference our soon-to-be-gone
	 * file_priv.
	 */
	spin_lock(&file_priv->mm.lock);
	while (!list_empty(&file_priv->mm.request_list)) {
		struct drm_i915_gem_request *request;

		request = list_first_entry(&file_priv->mm.request_list,
					   struct drm_i915_gem_request,
					   client_list);
		list_del(&request->client_list);
		request->file_priv = NULL;
	}
	spin_unlock(&file_priv->mm.lock);
}

static void
i915_gem_file_idle_work_handler(struct work_struct *work)
{
	struct drm_i915_file_private *file_priv =
		container_of(work, typeof(*file_priv), mm.idle_work.work);

	atomic_set(&file_priv->rps_wait_boost, false);
}

int i915_gem_open(struct drm_device *dev, struct drm_file *file)
{
	struct drm_i915_file_private *file_priv;
	int ret;

	DRM_DEBUG_DRIVER("\n");

	file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
	if (!file_priv)
		return -ENOMEM;

	file->driver_priv = file_priv;
	file_priv->dev_priv = dev->dev_private;
	file_priv->file = file;

	spin_lock_init(&file_priv->mm.lock);
	INIT_LIST_HEAD(&file_priv->mm.request_list);
	INIT_DELAYED_WORK(&file_priv->mm.idle_work,
			  i915_gem_file_idle_work_handler);

	ret = i915_gem_context_open(dev, file);
	if (ret)
		kfree(file_priv);

	return ret;
}

/**
 * i915_gem_track_fb - update frontbuffer tracking
 * old: current GEM buffer for the frontbuffer slots
 * new: new GEM buffer for the frontbuffer slots
 * frontbuffer_bits: bitmask of frontbuffer slots
 *
 * This updates the frontbuffer tracking bits @frontbuffer_bits by clearing them
 * from @old and setting them in @new. Both @old and @new can be NULL.
 */
void i915_gem_track_fb(struct drm_i915_gem_object *old,
		       struct drm_i915_gem_object *new,
		       unsigned frontbuffer_bits)
{
	if (old) {
		WARN_ON(!mutex_is_locked(&old->base.dev->struct_mutex));
		WARN_ON(!(old->frontbuffer_bits & frontbuffer_bits));
		old->frontbuffer_bits &= ~frontbuffer_bits;
	}

	if (new) {
		WARN_ON(!mutex_is_locked(&new->base.dev->struct_mutex));
		WARN_ON(new->frontbuffer_bits & frontbuffer_bits);
		new->frontbuffer_bits |= frontbuffer_bits;
	}
}

static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
{
	if (!mutex_is_locked(mutex))
		return false;

#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES)
	return mutex->owner == task;
#else
	/* Since UP may be pre-empted, we cannot assume that we own the lock */
	return false;
#endif
}

static bool i915_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
{
	if (!mutex_trylock(&dev->struct_mutex)) {
		if (!mutex_is_locked_by(&dev->struct_mutex, current))
			return false;

		if (to_i915(dev)->mm.shrinker_no_lock_stealing)
			return false;

		*unlock = false;
	} else
		*unlock = true;

	return true;
}

static int num_vma_bound(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma;
	int count = 0;

	list_for_each_entry(vma, &obj->vma_list, vma_link)
		if (drm_mm_node_allocated(&vma->node))
			count++;

	return count;
}

static unsigned long
i915_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
{
	struct drm_i915_private *dev_priv =
		container_of(shrinker, struct drm_i915_private, mm.shrinker);
	struct drm_device *dev = dev_priv->dev;
	struct drm_i915_gem_object *obj;
	unsigned long count;
	bool unlock;

	if (!i915_gem_shrinker_lock(dev, &unlock))
		return 0;

	count = 0;
	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list)
		if (obj->pages_pin_count == 0)
			count += obj->base.size >> PAGE_SHIFT;

	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (!i915_gem_obj_is_pinned(obj) &&
		    obj->pages_pin_count == num_vma_bound(obj))
			count += obj->base.size >> PAGE_SHIFT;
	}

	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	return count;
}

/* All the new VM stuff */
unsigned long i915_gem_obj_offset(struct drm_i915_gem_object *o,
				  struct i915_address_space *vm)
{
	struct drm_i915_private *dev_priv = o->base.dev->dev_private;
	struct i915_vma *vma;

	WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base);

	list_for_each_entry(vma, &o->vma_list, vma_link) {
		if (vma->vm == vm)
			return vma->node.start;

	}
	WARN(1, "%s vma for this object not found.\n",
	     i915_is_ggtt(vm) ? "global" : "ppgtt");
	return -1;
}

bool i915_gem_obj_bound(struct drm_i915_gem_object *o,
			struct i915_address_space *vm)
{
	struct i915_vma *vma;

	list_for_each_entry(vma, &o->vma_list, vma_link)
		if (vma->vm == vm && drm_mm_node_allocated(&vma->node))
			return true;

	return false;
}

bool i915_gem_obj_bound_any(struct drm_i915_gem_object *o)
{
	struct i915_vma *vma;

	list_for_each_entry(vma, &o->vma_list, vma_link)
		if (drm_mm_node_allocated(&vma->node))
			return true;

	return false;
}

unsigned long i915_gem_obj_size(struct drm_i915_gem_object *o,
				struct i915_address_space *vm)
{
	struct drm_i915_private *dev_priv = o->base.dev->dev_private;
	struct i915_vma *vma;

	WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base);

	BUG_ON(list_empty(&o->vma_list));

	list_for_each_entry(vma, &o->vma_list, vma_link)
		if (vma->vm == vm)
			return vma->node.size;

	return 0;
}

static unsigned long
i915_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
{
	struct drm_i915_private *dev_priv =
		container_of(shrinker, struct drm_i915_private, mm.shrinker);
	struct drm_device *dev = dev_priv->dev;
	unsigned long freed;
	bool unlock;

	if (!i915_gem_shrinker_lock(dev, &unlock))
		return SHRINK_STOP;

	freed = i915_gem_shrink(dev_priv,
				sc->nr_to_scan,
				I915_SHRINK_BOUND |
				I915_SHRINK_UNBOUND |
				I915_SHRINK_PURGEABLE);
	if (freed < sc->nr_to_scan)
		freed += i915_gem_shrink(dev_priv,
					 sc->nr_to_scan - freed,
					 I915_SHRINK_BOUND |
					 I915_SHRINK_UNBOUND);
	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	return freed;
}

static int
i915_gem_shrinker_oom(struct notifier_block *nb, unsigned long event, void *ptr)
{
	struct drm_i915_private *dev_priv =
		container_of(nb, struct drm_i915_private, mm.oom_notifier);
	struct drm_device *dev = dev_priv->dev;
	struct drm_i915_gem_object *obj;
	unsigned long timeout = msecs_to_jiffies(5000) + 1;
	unsigned long pinned, bound, unbound, freed_pages;
	bool was_interruptible;
	bool unlock;

	while (!i915_gem_shrinker_lock(dev, &unlock) && --timeout) {
		schedule_timeout_killable(1);
		if (fatal_signal_pending(current))
			return NOTIFY_DONE;
	}
	if (timeout == 0) {
		pr_err("Unable to purge GPU memory due lock contention.\n");
		return NOTIFY_DONE;
	}

	was_interruptible = dev_priv->mm.interruptible;
	dev_priv->mm.interruptible = false;

	freed_pages = i915_gem_shrink_all(dev_priv);

	dev_priv->mm.interruptible = was_interruptible;

	/* Because we may be allocating inside our own driver, we cannot
	 * assert that there are no objects with pinned pages that are not
	 * being pointed to by hardware.
	 */
	unbound = bound = pinned = 0;
	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
		if (!obj->base.filp) /* not backed by a freeable object */
			continue;

		if (obj->pages_pin_count)
			pinned += obj->base.size;
		else
			unbound += obj->base.size;
	}
	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (!obj->base.filp)
			continue;

		if (obj->pages_pin_count)
			pinned += obj->base.size;
		else
			bound += obj->base.size;
	}

	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	if (freed_pages || unbound || bound)
		pr_info("Purging GPU memory, %lu bytes freed, %lu bytes still pinned.\n",
			freed_pages << PAGE_SHIFT, pinned);
	if (unbound || bound)
		pr_err("%lu and %lu bytes still available in the "
		       "bound and unbound GPU page lists.\n",
		       bound, unbound);

	*(unsigned long *)ptr += freed_pages;
	return NOTIFY_DONE;
}

struct i915_vma *i915_gem_obj_to_ggtt(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma;

	vma = list_first_entry(&obj->vma_list, typeof(*vma), vma_link);
	if (vma->vm != i915_obj_to_ggtt(obj))
		return NULL;

	return vma;
}