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
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
5419
5420
5421
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443
5444
5445
5446
5447
5448
5449
5450
5451
5452
5453
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486
5487
5488
5489
5490
5491
5492
5493
5494
5495
5496
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507
5508
5509
5510
5511
5512
5513
5514
5515
5516
5517
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528
5529
5530
5531
5532
5533
5534
5535
5536
5537
5538
5539
5540
5541
5542
5543
5544
5545
5546
5547
5548
5549
5550
5551
5552
5553
5554
5555
5556
5557
5558
5559
5560
5561
5562
5563
5564
5565
5566
5567
5568
5569
5570
5571
5572
5573
5574
5575
5576
5577
5578
5579
5580
5581
5582
5583
5584
5585
5586
5587
5588
5589
5590
5591
5592
5593
5594
5595
5596
5597
5598
5599
5600
5601
5602
5603
5604
5605
5606
5607
5608
5609
5610
5611
5612
5613
5614
5615
5616
5617
5618
5619
5620
5621
5622
5623
5624
5625
5626
5627
5628
5629
5630
5631
5632
5633
5634
5635
5636
5637
5638
5639
5640
5641
5642
5643
5644
5645
5646
5647
5648
5649
5650
5651
5652
5653
5654
5655
5656
5657
5658
5659
5660
5661
5662
5663
5664
5665
5666
5667
5668
5669
5670
5671
5672
5673
5674
5675
5676
5677
5678
5679
5680
5681
5682
5683
5684
5685
5686
5687
5688
5689
5690
5691
5692
5693
5694
5695
5696
5697
5698
5699
5700
5701
5702
5703
5704
5705
5706
5707
5708
5709
5710
5711
5712
5713
5714
5715
5716
5717
5718
5719
5720
5721
5722
5723
5724
5725
5726
5727
5728
5729
5730
5731
5732
5733
5734
5735
5736
5737
5738
5739
5740
5741
5742
5743
5744
5745
5746
5747
5748
5749
5750
5751
5752
5753
5754
5755
5756
5757
5758
5759
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781
5782
5783
5784
5785
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804
5805
5806
5807
5808
5809
5810
5811
5812
5813
5814
5815
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826
5827
5828
5829
5830
5831
5832
5833
5834
5835
5836
5837
5838
5839
5840
5841
5842
5843
5844
5845
5846
5847
5848
5849
5850
5851
5852
5853
5854
5855
5856
5857
5858
5859
5860
5861
5862
5863
5864
5865
5866
5867
5868
5869
5870
5871
5872
5873
5874
5875
5876
5877
5878
5879
5880
5881
5882
5883
5884
5885
5886
5887
5888
5889
5890
5891
5892
5893
5894
5895
5896
5897
5898
5899
5900
5901
5902
5903
5904
5905
5906
5907
5908
5909
5910
5911
5912
5913
5914
5915
5916
5917
5918
5919
5920
5921
5922
5923
5924
5925
5926
5927
5928
5929
5930
5931
5932
5933
5934
5935
5936
5937
5938
5939
5940
5941
5942
5943
5944
5945
5946
5947
5948
5949
5950
5951
5952
5953
5954
5955
5956
5957
5958
5959
5960
5961
5962
5963
5964
5965
5966
5967
5968
5969
5970
5971
5972
5973
5974
5975
5976
5977
5978
5979
5980
5981
5982
5983
5984
5985
5986
5987
5988
5989
5990
5991
5992
5993
5994
5995
5996
5997
5998
5999
6000
6001
6002
6003
6004
6005
6006
6007
6008
6009
6010
6011
6012
6013
6014
6015
6016
6017
6018
6019
6020
6021
6022
6023
6024
6025
6026
6027
6028
6029
6030
6031
6032
6033
6034
6035
6036
6037
6038
6039
6040
6041
6042
6043
6044
6045
6046
6047
6048
6049
6050
6051
6052
6053
6054
6055
6056
6057
6058
6059
6060
6061
6062
6063
6064
6065
6066
6067
6068
6069
6070
6071
6072
6073
6074
6075
6076
6077
6078
6079
6080
6081
6082
6083
6084
6085
6086
6087
6088
6089
6090
6091
6092
6093
6094
6095
6096
6097
6098
6099
6100
6101
6102
6103
6104
6105
6106
6107
6108
6109
6110
6111
6112
6113
6114
6115
6116
6117
6118
6119
6120
6121
6122
6123
6124
6125
6126
6127
6128
6129
6130
6131
6132
6133
6134
6135
6136
6137
6138
6139
6140
6141
6142
6143
6144
6145
6146
6147
6148
6149
6150
6151
6152
6153
6154
6155
6156
6157
6158
6159
6160
6161
6162
6163
6164
6165
6166
6167
6168
6169
6170
6171
6172
6173
6174
6175
6176
6177
6178
6179
6180
6181
6182
6183
6184
6185
6186
6187
6188
6189
6190
6191
6192
6193
6194
6195
6196
6197
6198
6199
6200
6201
6202
6203
6204
6205
6206
6207
6208
6209
6210
6211
6212
6213
6214
6215
6216
6217
6218
6219
6220
6221
6222
6223
6224
6225
6226
6227
6228
6229
6230
6231
6232
6233
6234
6235
6236
6237
6238
6239
6240
6241
6242
6243
6244
6245
6246
6247
6248
6249
6250
6251
6252
6253
6254
6255
6256
6257
6258
6259
6260
6261
6262
6263
6264
6265
6266
6267
6268
6269
6270
6271
6272
6273
6274
6275
6276
6277
6278
6279
6280
6281
6282
6283
6284
6285
6286
6287
6288
6289
6290
6291
6292
6293
6294
6295
6296
6297
6298
6299
6300
6301
6302
6303
6304
6305
6306
6307
6308
6309
6310
6311
6312
6313
6314
6315
6316
6317
6318
6319
6320
6321
6322
6323
6324
6325
6326
6327
6328
6329
6330
6331
6332
6333
6334
6335
6336
6337
6338
6339
6340
6341
6342
6343
6344
6345
6346
6347
6348
6349
6350
6351
6352
6353
6354
6355
6356
6357
6358
6359
6360
6361
6362
6363
6364
6365
6366
6367
6368
6369
6370
6371
6372
6373
6374
6375
6376
6377
6378
6379
6380
6381
6382
6383
6384
6385
6386
6387
6388
6389
6390
6391
6392
6393
6394
6395
6396
6397
6398
6399
6400
6401
6402
6403
6404
6405
6406
6407
6408
6409
6410
6411
6412
6413
6414
6415
6416
6417
6418
6419
6420
6421
6422
6423
6424
6425
6426
6427
6428
6429
6430
6431
6432
6433
6434
6435
6436
6437
6438
6439
6440
6441
6442
6443
6444
6445
6446
6447
6448
6449
6450
6451
6452
6453
6454
6455
6456
6457
6458
6459
6460
6461
6462
6463
6464
6465
6466
6467
6468
6469
6470
6471
6472
6473
6474
6475
6476
6477
6478
6479
6480
6481
6482
6483
6484
6485
6486
6487
6488
6489
6490
6491
6492
6493
6494
6495
6496
6497
6498
6499
6500
6501
6502
6503
6504
6505
6506
6507
6508
6509
6510
6511
6512
6513
6514
6515
6516
6517
6518
6519
6520
6521
6522
6523
6524
6525
6526
6527
6528
6529
6530
6531
6532
6533
6534
6535
6536
6537
6538
6539
6540
6541
6542
6543
6544
6545
6546
6547
6548
6549
6550
6551
6552
6553
6554
6555
6556
6557
6558
6559
6560
6561
6562
6563
6564
6565
6566
6567
6568
6569
6570
6571
6572
6573
6574
6575
6576
6577
6578
6579
6580
6581
6582
6583
6584
6585
6586
6587
6588
6589
6590
6591
6592
6593
6594
6595
6596
6597
6598
6599
6600
6601
6602
6603
6604
6605
6606
6607
6608
6609
6610
6611
6612
6613
6614
6615
6616
6617
6618
6619
6620
6621
6622
6623
6624
6625
6626
6627
6628
6629
6630
6631
6632
6633
6634
6635
6636
6637
6638
6639
6640
6641
6642
6643
6644
6645
6646
6647
6648
6649
6650
6651
6652
6653
6654
6655
6656
6657
6658
6659
6660
6661
6662
6663
6664
6665
6666
6667
6668
6669
6670
6671
6672
6673
6674
6675
6676
6677
6678
6679
6680
6681
6682
6683
6684
6685
6686
6687
6688
6689
6690
6691
6692
6693
6694
6695
6696
6697
6698
6699
6700
6701
6702
6703
6704
6705
6706
6707
6708
6709
6710
6711
6712
6713
6714
6715
6716
6717
6718
6719
6720
6721
6722
6723
6724
6725
6726
6727
6728
6729
6730
6731
6732
6733
6734
6735
6736
6737
6738
6739
6740
6741
6742
6743
6744
6745
6746
6747
6748
6749
6750
6751
6752
6753
6754
6755
6756
6757
6758
6759
6760
6761
6762
6763
6764
6765
6766
6767
6768
6769
6770
6771
6772
6773
6774
6775
6776
6777
6778
6779
6780
6781
6782
6783
6784
6785
6786
6787
6788
6789
6790
6791
6792
6793
6794
6795
6796
6797
6798
6799
6800
6801
6802
6803
6804
6805
6806
6807
6808
6809
6810
6811
6812
6813
6814
6815
6816
6817
6818
6819
6820
6821
6822
6823
6824
6825
6826
6827
6828
6829
6830
6831
6832
6833
6834
6835
6836
6837
6838
6839
6840
6841
6842
6843
6844
6845
6846
6847
6848
6849
6850
6851
6852
6853
6854
6855
6856
6857
6858
6859
6860
6861
6862
6863
6864
6865
6866
6867
6868
6869
6870
6871
6872
6873
6874
6875
6876
6877
6878
6879
6880
6881
6882
6883
6884
6885
6886
6887
6888
6889
6890
6891
6892
6893
6894
6895
6896
6897
6898
6899
6900
6901
6902
6903
6904
6905
6906
6907
6908
6909
6910
6911
6912
6913
6914
6915
6916
6917
6918
6919
6920
6921
6922
6923
6924
6925
6926
6927
6928
6929
6930
6931
6932
6933
6934
6935
6936
6937
6938
6939
6940
6941
6942
6943
6944
6945
6946
6947
6948
6949
6950
6951
6952
6953
6954
6955
6956
6957
6958
6959
6960
6961
6962
6963
6964
6965
6966
6967
6968
6969
6970
6971
6972
6973
6974
6975
6976
6977
6978
6979
6980
6981
6982
6983
6984
6985
6986
6987
6988
6989
6990
6991
6992
6993
6994
6995
6996
6997
6998
6999
7000
7001
7002
7003
7004
7005
7006
7007
7008
7009
7010
7011
7012
7013
7014
7015
7016
7017
7018
7019
7020
7021
7022
7023
7024
7025
7026
7027
7028
7029
7030
7031
7032
7033
7034
7035
7036
7037
7038
7039
7040
7041
7042
7043
7044
7045
7046
7047
7048
7049
7050
7051
7052
7053
7054
7055
7056
7057
7058
7059
7060
7061
7062
7063
7064
7065
7066
7067
7068
7069
7070
7071
7072
7073
7074
7075
7076
7077
7078
7079
7080
7081
7082
7083
7084
7085
7086
7087
7088
7089
7090
7091
7092
7093
7094
7095
7096
7097
7098
7099
7100
7101
7102
7103
7104
7105
7106
7107
7108
7109
7110
7111
7112
7113
7114
7115
7116
7117
7118
7119
7120
7121
7122
7123
7124
7125
7126
7127
7128
7129
7130
7131
7132
7133
7134
7135
7136
7137
7138
7139
7140
7141
7142
7143
7144
7145
7146
7147
7148
7149
7150
7151
7152
7153
7154
7155
7156
7157
7158
7159
7160
7161
7162
7163
7164
7165
7166
7167
7168
7169
7170
7171
7172
7173
7174
7175
7176
7177
7178
7179
7180
7181
7182
7183
7184
7185
7186
7187
7188
7189
7190
7191
7192
7193
7194
7195
7196
7197
7198
7199
7200
7201
7202
7203
7204
7205
7206
7207
7208
7209
7210
7211
7212
7213
7214
7215
7216
7217
7218
7219
7220
7221
7222
7223
7224
7225
7226
7227
7228
7229
7230
7231
7232
7233
7234
7235
7236
7237
7238
7239
7240
7241
7242
7243
7244
7245
7246
7247
7248
7249
7250
7251
7252
7253
7254
7255
7256
7257
7258
7259
7260
7261
7262
7263
7264
7265
7266
7267
7268
7269
7270
7271
7272
7273
7274
7275
7276
7277
7278
7279
7280
7281
7282
7283
7284
7285
7286
7287
7288
7289
7290
7291
7292
7293
7294
7295
7296
7297
7298
7299
7300
7301
7302
7303
7304
7305
7306
7307
7308
7309
7310
7311
7312
7313
7314
7315
7316
7317
7318
7319
7320
7321
7322
7323
7324
7325
7326
7327
7328
7329
7330
7331
7332
7333
7334
7335
7336
7337
7338
7339
7340
7341
7342
7343
7344
7345
7346
7347
7348
7349
7350
7351
7352
7353
7354
7355
7356
7357
7358
7359
7360
7361
7362
7363
7364
7365
7366
7367
7368
7369
7370
7371
7372
7373
7374
7375
7376
7377
7378
7379
7380
7381
7382
7383
7384
7385
7386
7387
7388
7389
7390
7391
7392
7393
7394
7395
7396
7397
7398
7399
7400
7401
7402
7403
7404
7405
7406
7407
7408
7409
7410
7411
7412
7413
7414
7415
7416
7417
7418
7419
7420
7421
7422
7423
7424
7425
7426
7427
7428
7429
7430
7431
7432
7433
7434
7435
7436
7437
7438
7439
7440
7441
7442
7443
7444
7445
7446
7447
7448
7449
7450
7451
7452
7453
7454
7455
7456
7457
7458
7459
7460
7461
7462
7463
7464
7465
7466
7467
7468
7469
7470
7471
7472
7473
7474
7475
7476
7477
7478
7479
7480
7481
7482
7483
7484
7485
7486
7487
7488
7489
7490
7491
7492
7493
7494
7495
7496
7497
7498
7499
7500
7501
7502
7503
7504
7505
7506
7507
7508
7509
7510
7511
7512
7513
7514
7515
7516
7517
7518
7519
7520
7521
7522
7523
7524
7525
7526
7527
7528
7529
7530
7531
7532
7533
7534
7535
7536
7537
7538
7539
7540
7541
7542
7543
7544
7545
7546
7547
7548
7549
7550
7551
7552
7553
7554
7555
7556
7557
7558
7559
7560
7561
7562
7563
7564
7565
7566
7567
7568
7569
7570
7571
7572
7573
7574
7575
7576
7577
7578
7579
7580
7581
7582
7583
7584
7585
7586
7587
7588
7589
7590
7591
7592
7593
7594
7595
7596
7597
7598
7599
7600
7601
7602
7603
7604
7605
7606
7607
7608
7609
7610
7611
7612
7613
7614
7615
7616
7617
7618
7619
7620
7621
7622
7623
7624
7625
7626
7627
7628
7629
7630
7631
7632
7633
7634
7635
7636
7637
7638
7639
7640
7641
7642
7643
7644
7645
7646
7647
7648
7649
7650
7651
7652
7653
7654
7655
7656
7657
7658
7659
7660
7661
7662
7663
7664
7665
7666
7667
7668
7669
7670
7671
7672
7673
7674
7675
7676
7677
7678
7679
7680
7681
7682
7683
7684
7685
7686
7687
7688
7689
7690
7691
7692
7693
7694
7695
7696
7697
7698
7699
7700
7701
7702
7703
7704
7705
7706
7707
7708
7709
7710
7711
7712
7713
7714
7715
7716
7717
7718
7719
7720
7721
7722
7723
7724
7725
7726
7727
7728
7729
7730
7731
7732
7733
7734
7735
7736
7737
7738
7739
7740
7741
7742
7743
7744
7745
7746
7747
7748
7749
7750
7751
7752
7753
7754
7755
7756
7757
7758
7759
7760
7761
7762
7763
7764
7765
7766
7767
7768
7769
7770
7771
7772
7773
7774
7775
7776
7777
7778
7779
7780
7781
7782
7783
7784
7785
7786
7787
7788
7789
7790
7791
7792
7793
7794
7795
7796
7797
7798
7799
7800
7801
7802
7803
7804
7805
7806
7807
7808
7809
7810
7811
7812
7813
7814
7815
7816
7817
7818
7819
7820
7821
7822
7823
7824
7825
7826
7827
7828
7829
7830
7831
7832
7833
7834
7835
7836
7837
7838
7839
7840
7841
7842
7843
7844
7845
7846
7847
7848
7849
7850
7851
7852
7853
7854
7855
7856
7857
7858
7859
7860
7861
7862
7863
7864
7865
7866
7867
7868
7869
7870
7871
7872
7873
7874
7875
7876
7877
7878
7879
7880
7881
7882
7883
7884
7885
7886
7887
7888
7889
7890
7891
7892
7893
7894
7895
7896
7897
7898
7899
7900
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Generic hugetlb support.
* (C) Nadia Yvette Chambers, April 2004
*/
#include <linux/list.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/sysctl.h>
#include <linux/highmem.h>
#include <linux/mmu_notifier.h>
#include <linux/nodemask.h>
#include <linux/pagemap.h>
#include <linux/mempolicy.h>
#include <linux/compiler.h>
#include <linux/cpuset.h>
#include <linux/mutex.h>
#include <linux/memblock.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
#include <linux/sched/mm.h>
#include <linux/mmdebug.h>
#include <linux/sched/signal.h>
#include <linux/rmap.h>
#include <linux/string_helpers.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/jhash.h>
#include <linux/numa.h>
#include <linux/llist.h>
#include <linux/cma.h>
#include <linux/migrate.h>
#include <linux/nospec.h>
#include <linux/delayacct.h>
#include <linux/memory.h>
#include <linux/mm_inline.h>
#include <linux/padata.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <linux/io.h>
#include <linux/hugetlb.h>
#include <linux/hugetlb_cgroup.h>
#include <linux/node.h>
#include <linux/page_owner.h>
#include "internal.h"
#include "hugetlb_vmemmap.h"
int hugetlb_max_hstate __read_mostly;
unsigned int default_hstate_idx;
struct hstate hstates[HUGE_MAX_HSTATE];
#ifdef CONFIG_CMA
static struct cma *hugetlb_cma[MAX_NUMNODES];
static unsigned long hugetlb_cma_size_in_node[MAX_NUMNODES] __initdata;
static bool hugetlb_cma_folio(struct folio *folio, unsigned int order)
{
return cma_pages_valid(hugetlb_cma[folio_nid(folio)], &folio->page,
1 << order);
}
#else
static bool hugetlb_cma_folio(struct folio *folio, unsigned int order)
{
return false;
}
#endif
static unsigned long hugetlb_cma_size __initdata;
__initdata struct list_head huge_boot_pages[MAX_NUMNODES];
/* for command line parsing */
static struct hstate * __initdata parsed_hstate;
static unsigned long __initdata default_hstate_max_huge_pages;
static bool __initdata parsed_valid_hugepagesz = true;
static bool __initdata parsed_default_hugepagesz;
static unsigned int default_hugepages_in_node[MAX_NUMNODES] __initdata;
/*
* Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages,
* free_huge_pages, and surplus_huge_pages.
*/
DEFINE_SPINLOCK(hugetlb_lock);
/*
* Serializes faults on the same logical page. This is used to
* prevent spurious OOMs when the hugepage pool is fully utilized.
*/
static int num_fault_mutexes;
struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp;
/* Forward declaration */
static int hugetlb_acct_memory(struct hstate *h, long delta);
static void hugetlb_vma_lock_free(struct vm_area_struct *vma);
static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma);
static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma);
static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
unsigned long start, unsigned long end);
static struct resv_map *vma_resv_map(struct vm_area_struct *vma);
static inline bool subpool_is_free(struct hugepage_subpool *spool)
{
if (spool->count)
return false;
if (spool->max_hpages != -1)
return spool->used_hpages == 0;
if (spool->min_hpages != -1)
return spool->rsv_hpages == spool->min_hpages;
return true;
}
static inline void unlock_or_release_subpool(struct hugepage_subpool *spool,
unsigned long irq_flags)
{
spin_unlock_irqrestore(&spool->lock, irq_flags);
/* If no pages are used, and no other handles to the subpool
* remain, give up any reservations based on minimum size and
* free the subpool */
if (subpool_is_free(spool)) {
if (spool->min_hpages != -1)
hugetlb_acct_memory(spool->hstate,
-spool->min_hpages);
kfree(spool);
}
}
struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages,
long min_hpages)
{
struct hugepage_subpool *spool;
spool = kzalloc(sizeof(*spool), GFP_KERNEL);
if (!spool)
return NULL;
spin_lock_init(&spool->lock);
spool->count = 1;
spool->max_hpages = max_hpages;
spool->hstate = h;
spool->min_hpages = min_hpages;
if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) {
kfree(spool);
return NULL;
}
spool->rsv_hpages = min_hpages;
return spool;
}
void hugepage_put_subpool(struct hugepage_subpool *spool)
{
unsigned long flags;
spin_lock_irqsave(&spool->lock, flags);
BUG_ON(!spool->count);
spool->count--;
unlock_or_release_subpool(spool, flags);
}
/*
* Subpool accounting for allocating and reserving pages.
* Return -ENOMEM if there are not enough resources to satisfy the
* request. Otherwise, return the number of pages by which the
* global pools must be adjusted (upward). The returned value may
* only be different than the passed value (delta) in the case where
* a subpool minimum size must be maintained.
*/
static long hugepage_subpool_get_pages(struct hugepage_subpool *spool,
long delta)
{
long ret = delta;
if (!spool)
return ret;
spin_lock_irq(&spool->lock);
if (spool->max_hpages != -1) { /* maximum size accounting */
if ((spool->used_hpages + delta) <= spool->max_hpages)
spool->used_hpages += delta;
else {
ret = -ENOMEM;
goto unlock_ret;
}
}
/* minimum size accounting */
if (spool->min_hpages != -1 && spool->rsv_hpages) {
if (delta > spool->rsv_hpages) {
/*
* Asking for more reserves than those already taken on
* behalf of subpool. Return difference.
*/
ret = delta - spool->rsv_hpages;
spool->rsv_hpages = 0;
} else {
ret = 0; /* reserves already accounted for */
spool->rsv_hpages -= delta;
}
}
unlock_ret:
spin_unlock_irq(&spool->lock);
return ret;
}
/*
* Subpool accounting for freeing and unreserving pages.
* Return the number of global page reservations that must be dropped.
* The return value may only be different than the passed value (delta)
* in the case where a subpool minimum size must be maintained.
*/
static long hugepage_subpool_put_pages(struct hugepage_subpool *spool,
long delta)
{
long ret = delta;
unsigned long flags;
if (!spool)
return delta;
spin_lock_irqsave(&spool->lock, flags);
if (spool->max_hpages != -1) /* maximum size accounting */
spool->used_hpages -= delta;
/* minimum size accounting */
if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) {
if (spool->rsv_hpages + delta <= spool->min_hpages)
ret = 0;
else
ret = spool->rsv_hpages + delta - spool->min_hpages;
spool->rsv_hpages += delta;
if (spool->rsv_hpages > spool->min_hpages)
spool->rsv_hpages = spool->min_hpages;
}
/*
* If hugetlbfs_put_super couldn't free spool due to an outstanding
* quota reference, free it now.
*/
unlock_or_release_subpool(spool, flags);
return ret;
}
static inline struct hugepage_subpool *subpool_inode(struct inode *inode)
{
return HUGETLBFS_SB(inode->i_sb)->spool;
}
static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma)
{
return subpool_inode(file_inode(vma->vm_file));
}
/*
* hugetlb vma_lock helper routines
*/
void hugetlb_vma_lock_read(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
down_read(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
down_read(&resv_map->rw_sema);
}
}
void hugetlb_vma_unlock_read(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
up_read(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
up_read(&resv_map->rw_sema);
}
}
void hugetlb_vma_lock_write(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
down_write(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
down_write(&resv_map->rw_sema);
}
}
void hugetlb_vma_unlock_write(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
up_write(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
up_write(&resv_map->rw_sema);
}
}
int hugetlb_vma_trylock_write(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
return down_write_trylock(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
return down_write_trylock(&resv_map->rw_sema);
}
return 1;
}
void hugetlb_vma_assert_locked(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
lockdep_assert_held(&vma_lock->rw_sema);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
lockdep_assert_held(&resv_map->rw_sema);
}
}
void hugetlb_vma_lock_release(struct kref *kref)
{
struct hugetlb_vma_lock *vma_lock = container_of(kref,
struct hugetlb_vma_lock, refs);
kfree(vma_lock);
}
static void __hugetlb_vma_unlock_write_put(struct hugetlb_vma_lock *vma_lock)
{
struct vm_area_struct *vma = vma_lock->vma;
/*
* vma_lock structure may or not be released as a result of put,
* it certainly will no longer be attached to vma so clear pointer.
* Semaphore synchronizes access to vma_lock->vma field.
*/
vma_lock->vma = NULL;
vma->vm_private_data = NULL;
up_write(&vma_lock->rw_sema);
kref_put(&vma_lock->refs, hugetlb_vma_lock_release);
}
static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma)
{
if (__vma_shareable_lock(vma)) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
__hugetlb_vma_unlock_write_put(vma_lock);
} else if (__vma_private_lock(vma)) {
struct resv_map *resv_map = vma_resv_map(vma);
/* no free for anon vmas, but still need to unlock */
up_write(&resv_map->rw_sema);
}
}
static void hugetlb_vma_lock_free(struct vm_area_struct *vma)
{
/*
* Only present in sharable vmas.
*/
if (!vma || !__vma_shareable_lock(vma))
return;
if (vma->vm_private_data) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
down_write(&vma_lock->rw_sema);
__hugetlb_vma_unlock_write_put(vma_lock);
}
}
static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma)
{
struct hugetlb_vma_lock *vma_lock;
/* Only establish in (flags) sharable vmas */
if (!vma || !(vma->vm_flags & VM_MAYSHARE))
return;
/* Should never get here with non-NULL vm_private_data */
if (vma->vm_private_data)
return;
vma_lock = kmalloc(sizeof(*vma_lock), GFP_KERNEL);
if (!vma_lock) {
/*
* If we can not allocate structure, then vma can not
* participate in pmd sharing. This is only a possible
* performance enhancement and memory saving issue.
* However, the lock is also used to synchronize page
* faults with truncation. If the lock is not present,
* unlikely races could leave pages in a file past i_size
* until the file is removed. Warn in the unlikely case of
* allocation failure.
*/
pr_warn_once("HugeTLB: unable to allocate vma specific lock\n");
return;
}
kref_init(&vma_lock->refs);
init_rwsem(&vma_lock->rw_sema);
vma_lock->vma = vma;
vma->vm_private_data = vma_lock;
}
/* Helper that removes a struct file_region from the resv_map cache and returns
* it for use.
*/
static struct file_region *
get_file_region_entry_from_cache(struct resv_map *resv, long from, long to)
{
struct file_region *nrg;
VM_BUG_ON(resv->region_cache_count <= 0);
resv->region_cache_count--;
nrg = list_first_entry(&resv->region_cache, struct file_region, link);
list_del(&nrg->link);
nrg->from = from;
nrg->to = to;
return nrg;
}
static void copy_hugetlb_cgroup_uncharge_info(struct file_region *nrg,
struct file_region *rg)
{
#ifdef CONFIG_CGROUP_HUGETLB
nrg->reservation_counter = rg->reservation_counter;
nrg->css = rg->css;
if (rg->css)
css_get(rg->css);
#endif
}
/* Helper that records hugetlb_cgroup uncharge info. */
static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg,
struct hstate *h,
struct resv_map *resv,
struct file_region *nrg)
{
#ifdef CONFIG_CGROUP_HUGETLB
if (h_cg) {
nrg->reservation_counter =
&h_cg->rsvd_hugepage[hstate_index(h)];
nrg->css = &h_cg->css;
/*
* The caller will hold exactly one h_cg->css reference for the
* whole contiguous reservation region. But this area might be
* scattered when there are already some file_regions reside in
* it. As a result, many file_regions may share only one css
* reference. In order to ensure that one file_region must hold
* exactly one h_cg->css reference, we should do css_get for
* each file_region and leave the reference held by caller
* untouched.
*/
css_get(&h_cg->css);
if (!resv->pages_per_hpage)
resv->pages_per_hpage = pages_per_huge_page(h);
/* pages_per_hpage should be the same for all entries in
* a resv_map.
*/
VM_BUG_ON(resv->pages_per_hpage != pages_per_huge_page(h));
} else {
nrg->reservation_counter = NULL;
nrg->css = NULL;
}
#endif
}
static void put_uncharge_info(struct file_region *rg)
{
#ifdef CONFIG_CGROUP_HUGETLB
if (rg->css)
css_put(rg->css);
#endif
}
static bool has_same_uncharge_info(struct file_region *rg,
struct file_region *org)
{
#ifdef CONFIG_CGROUP_HUGETLB
return rg->reservation_counter == org->reservation_counter &&
rg->css == org->css;
#else
return true;
#endif
}
static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
{
struct file_region *nrg, *prg;
prg = list_prev_entry(rg, link);
if (&prg->link != &resv->regions && prg->to == rg->from &&
has_same_uncharge_info(prg, rg)) {
prg->to = rg->to;
list_del(&rg->link);
put_uncharge_info(rg);
kfree(rg);
rg = prg;
}
nrg = list_next_entry(rg, link);
if (&nrg->link != &resv->regions && nrg->from == rg->to &&
has_same_uncharge_info(nrg, rg)) {
nrg->from = rg->from;
list_del(&rg->link);
put_uncharge_info(rg);
kfree(rg);
}
}
static inline long
hugetlb_resv_map_add(struct resv_map *map, struct list_head *rg, long from,
long to, struct hstate *h, struct hugetlb_cgroup *cg,
long *regions_needed)
{
struct file_region *nrg;
if (!regions_needed) {
nrg = get_file_region_entry_from_cache(map, from, to);
record_hugetlb_cgroup_uncharge_info(cg, h, map, nrg);
list_add(&nrg->link, rg);
coalesce_file_region(map, nrg);
} else
*regions_needed += 1;
return to - from;
}
/*
* Must be called with resv->lock held.
*
* Calling this with regions_needed != NULL will count the number of pages
* to be added but will not modify the linked list. And regions_needed will
* indicate the number of file_regions needed in the cache to carry out to add
* the regions for this range.
*/
static long add_reservation_in_range(struct resv_map *resv, long f, long t,
struct hugetlb_cgroup *h_cg,
struct hstate *h, long *regions_needed)
{
long add = 0;
struct list_head *head = &resv->regions;
long last_accounted_offset = f;
struct file_region *iter, *trg = NULL;
struct list_head *rg = NULL;
if (regions_needed)
*regions_needed = 0;
/* In this loop, we essentially handle an entry for the range
* [last_accounted_offset, iter->from), at every iteration, with some
* bounds checking.
*/
list_for_each_entry_safe(iter, trg, head, link) {
/* Skip irrelevant regions that start before our range. */
if (iter->from < f) {
/* If this region ends after the last accounted offset,
* then we need to update last_accounted_offset.
*/
if (iter->to > last_accounted_offset)
last_accounted_offset = iter->to;
continue;
}
/* When we find a region that starts beyond our range, we've
* finished.
*/
if (iter->from >= t) {
rg = iter->link.prev;
break;
}
/* Add an entry for last_accounted_offset -> iter->from, and
* update last_accounted_offset.
*/
if (iter->from > last_accounted_offset)
add += hugetlb_resv_map_add(resv, iter->link.prev,
last_accounted_offset,
iter->from, h, h_cg,
regions_needed);
last_accounted_offset = iter->to;
}
/* Handle the case where our range extends beyond
* last_accounted_offset.
*/
if (!rg)
rg = head->prev;
if (last_accounted_offset < t)
add += hugetlb_resv_map_add(resv, rg, last_accounted_offset,
t, h, h_cg, regions_needed);
return add;
}
/* Must be called with resv->lock acquired. Will drop lock to allocate entries.
*/
static int allocate_file_region_entries(struct resv_map *resv,
int regions_needed)
__must_hold(&resv->lock)
{
LIST_HEAD(allocated_regions);
int to_allocate = 0, i = 0;
struct file_region *trg = NULL, *rg = NULL;
VM_BUG_ON(regions_needed < 0);
/*
* Check for sufficient descriptors in the cache to accommodate
* the number of in progress add operations plus regions_needed.
*
* This is a while loop because when we drop the lock, some other call
* to region_add or region_del may have consumed some region_entries,
* so we keep looping here until we finally have enough entries for
* (adds_in_progress + regions_needed).
*/
while (resv->region_cache_count <
(resv->adds_in_progress + regions_needed)) {
to_allocate = resv->adds_in_progress + regions_needed -
resv->region_cache_count;
/* At this point, we should have enough entries in the cache
* for all the existing adds_in_progress. We should only be
* needing to allocate for regions_needed.
*/
VM_BUG_ON(resv->region_cache_count < resv->adds_in_progress);
spin_unlock(&resv->lock);
for (i = 0; i < to_allocate; i++) {
trg = kmalloc(sizeof(*trg), GFP_KERNEL);
if (!trg)
goto out_of_memory;
list_add(&trg->link, &allocated_regions);
}
spin_lock(&resv->lock);
list_splice(&allocated_regions, &resv->region_cache);
resv->region_cache_count += to_allocate;
}
return 0;
out_of_memory:
list_for_each_entry_safe(rg, trg, &allocated_regions, link) {
list_del(&rg->link);
kfree(rg);
}
return -ENOMEM;
}
/*
* Add the huge page range represented by [f, t) to the reserve
* map. Regions will be taken from the cache to fill in this range.
* Sufficient regions should exist in the cache due to the previous
* call to region_chg with the same range, but in some cases the cache will not
* have sufficient entries due to races with other code doing region_add or
* region_del. The extra needed entries will be allocated.
*
* regions_needed is the out value provided by a previous call to region_chg.
*
* Return the number of new huge pages added to the map. This number is greater
* than or equal to zero. If file_region entries needed to be allocated for
* this operation and we were not able to allocate, it returns -ENOMEM.
* region_add of regions of length 1 never allocate file_regions and cannot
* fail; region_chg will always allocate at least 1 entry and a region_add for
* 1 page will only require at most 1 entry.
*/
static long region_add(struct resv_map *resv, long f, long t,
long in_regions_needed, struct hstate *h,
struct hugetlb_cgroup *h_cg)
{
long add = 0, actual_regions_needed = 0;
spin_lock(&resv->lock);
retry:
/* Count how many regions are actually needed to execute this add. */
add_reservation_in_range(resv, f, t, NULL, NULL,
&actual_regions_needed);
/*
* Check for sufficient descriptors in the cache to accommodate
* this add operation. Note that actual_regions_needed may be greater
* than in_regions_needed, as the resv_map may have been modified since
* the region_chg call. In this case, we need to make sure that we
* allocate extra entries, such that we have enough for all the
* existing adds_in_progress, plus the excess needed for this
* operation.
*/
if (actual_regions_needed > in_regions_needed &&
resv->region_cache_count <
resv->adds_in_progress +
(actual_regions_needed - in_regions_needed)) {
/* region_add operation of range 1 should never need to
* allocate file_region entries.
*/
VM_BUG_ON(t - f <= 1);
if (allocate_file_region_entries(
resv, actual_regions_needed - in_regions_needed)) {
return -ENOMEM;
}
goto retry;
}
add = add_reservation_in_range(resv, f, t, h_cg, h, NULL);
resv->adds_in_progress -= in_regions_needed;
spin_unlock(&resv->lock);
return add;
}
/*
* Examine the existing reserve map and determine how many
* huge pages in the specified range [f, t) are NOT currently
* represented. This routine is called before a subsequent
* call to region_add that will actually modify the reserve
* map to add the specified range [f, t). region_chg does
* not change the number of huge pages represented by the
* map. A number of new file_region structures is added to the cache as a
* placeholder, for the subsequent region_add call to use. At least 1
* file_region structure is added.
*
* out_regions_needed is the number of regions added to the
* resv->adds_in_progress. This value needs to be provided to a follow up call
* to region_add or region_abort for proper accounting.
*
* Returns the number of huge pages that need to be added to the existing
* reservation map for the range [f, t). This number is greater or equal to
* zero. -ENOMEM is returned if a new file_region structure or cache entry
* is needed and can not be allocated.
*/
static long region_chg(struct resv_map *resv, long f, long t,
long *out_regions_needed)
{
long chg = 0;
spin_lock(&resv->lock);
/* Count how many hugepages in this range are NOT represented. */
chg = add_reservation_in_range(resv, f, t, NULL, NULL,
out_regions_needed);
if (*out_regions_needed == 0)
*out_regions_needed = 1;
if (allocate_file_region_entries(resv, *out_regions_needed))
return -ENOMEM;
resv->adds_in_progress += *out_regions_needed;
spin_unlock(&resv->lock);
return chg;
}
/*
* Abort the in progress add operation. The adds_in_progress field
* of the resv_map keeps track of the operations in progress between
* calls to region_chg and region_add. Operations are sometimes
* aborted after the call to region_chg. In such cases, region_abort
* is called to decrement the adds_in_progress counter. regions_needed
* is the value returned by the region_chg call, it is used to decrement
* the adds_in_progress counter.
*
* NOTE: The range arguments [f, t) are not needed or used in this
* routine. They are kept to make reading the calling code easier as
* arguments will match the associated region_chg call.
*/
static void region_abort(struct resv_map *resv, long f, long t,
long regions_needed)
{
spin_lock(&resv->lock);
VM_BUG_ON(!resv->region_cache_count);
resv->adds_in_progress -= regions_needed;
spin_unlock(&resv->lock);
}
/*
* Delete the specified range [f, t) from the reserve map. If the
* t parameter is LONG_MAX, this indicates that ALL regions after f
* should be deleted. Locate the regions which intersect [f, t)
* and either trim, delete or split the existing regions.
*
* Returns the number of huge pages deleted from the reserve map.
* In the normal case, the return value is zero or more. In the
* case where a region must be split, a new region descriptor must
* be allocated. If the allocation fails, -ENOMEM will be returned.
* NOTE: If the parameter t == LONG_MAX, then we will never split
* a region and possibly return -ENOMEM. Callers specifying
* t == LONG_MAX do not need to check for -ENOMEM error.
*/
static long region_del(struct resv_map *resv, long f, long t)
{
struct list_head *head = &resv->regions;
struct file_region *rg, *trg;
struct file_region *nrg = NULL;
long del = 0;
retry:
spin_lock(&resv->lock);
list_for_each_entry_safe(rg, trg, head, link) {
/*
* Skip regions before the range to be deleted. file_region
* ranges are normally of the form [from, to). However, there
* may be a "placeholder" entry in the map which is of the form
* (from, to) with from == to. Check for placeholder entries
* at the beginning of the range to be deleted.
*/
if (rg->to <= f && (rg->to != rg->from || rg->to != f))
continue;
if (rg->from >= t)
break;
if (f > rg->from && t < rg->to) { /* Must split region */
/*
* Check for an entry in the cache before dropping
* lock and attempting allocation.
*/
if (!nrg &&
resv->region_cache_count > resv->adds_in_progress) {
nrg = list_first_entry(&resv->region_cache,
struct file_region,
link);
list_del(&nrg->link);
resv->region_cache_count--;
}
if (!nrg) {
spin_unlock(&resv->lock);
nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
if (!nrg)
return -ENOMEM;
goto retry;
}
del += t - f;
hugetlb_cgroup_uncharge_file_region(
resv, rg, t - f, false);
/* New entry for end of split region */
nrg->from = t;
nrg->to = rg->to;
copy_hugetlb_cgroup_uncharge_info(nrg, rg);
INIT_LIST_HEAD(&nrg->link);
/* Original entry is trimmed */
rg->to = f;
list_add(&nrg->link, &rg->link);
nrg = NULL;
break;
}
if (f <= rg->from && t >= rg->to) { /* Remove entire region */
del += rg->to - rg->from;
hugetlb_cgroup_uncharge_file_region(resv, rg,
rg->to - rg->from, true);
list_del(&rg->link);
kfree(rg);
continue;
}
if (f <= rg->from) { /* Trim beginning of region */
hugetlb_cgroup_uncharge_file_region(resv, rg,
t - rg->from, false);
del += t - rg->from;
rg->from = t;
} else { /* Trim end of region */
hugetlb_cgroup_uncharge_file_region(resv, rg,
rg->to - f, false);
del += rg->to - f;
rg->to = f;
}
}
spin_unlock(&resv->lock);
kfree(nrg);
return del;
}
/*
* A rare out of memory error was encountered which prevented removal of
* the reserve map region for a page. The huge page itself was free'ed
* and removed from the page cache. This routine will adjust the subpool
* usage count, and the global reserve count if needed. By incrementing
* these counts, the reserve map entry which could not be deleted will
* appear as a "reserved" entry instead of simply dangling with incorrect
* counts.
*/
void hugetlb_fix_reserve_counts(struct inode *inode)
{
struct hugepage_subpool *spool = subpool_inode(inode);
long rsv_adjust;
bool reserved = false;
rsv_adjust = hugepage_subpool_get_pages(spool, 1);
if (rsv_adjust > 0) {
struct hstate *h = hstate_inode(inode);
if (!hugetlb_acct_memory(h, 1))
reserved = true;
} else if (!rsv_adjust) {
reserved = true;
}
if (!reserved)
pr_warn("hugetlb: Huge Page Reserved count may go negative.\n");
}
/*
* Count and return the number of huge pages in the reserve map
* that intersect with the range [f, t).
*/
static long region_count(struct resv_map *resv, long f, long t)
{
struct list_head *head = &resv->regions;
struct file_region *rg;
long chg = 0;
spin_lock(&resv->lock);
/* Locate each segment we overlap with, and count that overlap. */
list_for_each_entry(rg, head, link) {
long seg_from;
long seg_to;
if (rg->to <= f)
continue;
if (rg->from >= t)
break;
seg_from = max(rg->from, f);
seg_to = min(rg->to, t);
chg += seg_to - seg_from;
}
spin_unlock(&resv->lock);
return chg;
}
/*
* Convert the address within this vma to the page offset within
* the mapping, huge page units here.
*/
static pgoff_t vma_hugecache_offset(struct hstate *h,
struct vm_area_struct *vma, unsigned long address)
{
return ((address - vma->vm_start) >> huge_page_shift(h)) +
(vma->vm_pgoff >> huge_page_order(h));
}
/**
* vma_kernel_pagesize - Page size granularity for this VMA.
* @vma: The user mapping.
*
* Folios in this VMA will be aligned to, and at least the size of the
* number of bytes returned by this function.
*
* Return: The default size of the folios allocated when backing a VMA.
*/
unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
{
if (vma->vm_ops && vma->vm_ops->pagesize)
return vma->vm_ops->pagesize(vma);
return PAGE_SIZE;
}
EXPORT_SYMBOL_GPL(vma_kernel_pagesize);
/*
* Return the page size being used by the MMU to back a VMA. In the majority
* of cases, the page size used by the kernel matches the MMU size. On
* architectures where it differs, an architecture-specific 'strong'
* version of this symbol is required.
*/
__weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
{
return vma_kernel_pagesize(vma);
}
/*
* Flags for MAP_PRIVATE reservations. These are stored in the bottom
* bits of the reservation map pointer, which are always clear due to
* alignment.
*/
#define HPAGE_RESV_OWNER (1UL << 0)
#define HPAGE_RESV_UNMAPPED (1UL << 1)
#define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED)
/*
* These helpers are used to track how many pages are reserved for
* faults in a MAP_PRIVATE mapping. Only the process that called mmap()
* is guaranteed to have their future faults succeed.
*
* With the exception of hugetlb_dup_vma_private() which is called at fork(),
* the reserve counters are updated with the hugetlb_lock held. It is safe
* to reset the VMA at fork() time as it is not in use yet and there is no
* chance of the global counters getting corrupted as a result of the values.
*
* The private mapping reservation is represented in a subtly different
* manner to a shared mapping. A shared mapping has a region map associated
* with the underlying file, this region map represents the backing file
* pages which have ever had a reservation assigned which this persists even
* after the page is instantiated. A private mapping has a region map
* associated with the original mmap which is attached to all VMAs which
* reference it, this region map represents those offsets which have consumed
* reservation ie. where pages have been instantiated.
*/
static unsigned long get_vma_private_data(struct vm_area_struct *vma)
{
return (unsigned long)vma->vm_private_data;
}
static void set_vma_private_data(struct vm_area_struct *vma,
unsigned long value)
{
vma->vm_private_data = (void *)value;
}
static void
resv_map_set_hugetlb_cgroup_uncharge_info(struct resv_map *resv_map,
struct hugetlb_cgroup *h_cg,
struct hstate *h)
{
#ifdef CONFIG_CGROUP_HUGETLB
if (!h_cg || !h) {
resv_map->reservation_counter = NULL;
resv_map->pages_per_hpage = 0;
resv_map->css = NULL;
} else {
resv_map->reservation_counter =
&h_cg->rsvd_hugepage[hstate_index(h)];
resv_map->pages_per_hpage = pages_per_huge_page(h);
resv_map->css = &h_cg->css;
}
#endif
}
struct resv_map *resv_map_alloc(void)
{
struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL);
if (!resv_map || !rg) {
kfree(resv_map);
kfree(rg);
return NULL;
}
kref_init(&resv_map->refs);
spin_lock_init(&resv_map->lock);
INIT_LIST_HEAD(&resv_map->regions);
init_rwsem(&resv_map->rw_sema);
resv_map->adds_in_progress = 0;
/*
* Initialize these to 0. On shared mappings, 0's here indicate these
* fields don't do cgroup accounting. On private mappings, these will be
* re-initialized to the proper values, to indicate that hugetlb cgroup
* reservations are to be un-charged from here.
*/
resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, NULL, NULL);
INIT_LIST_HEAD(&resv_map->region_cache);
list_add(&rg->link, &resv_map->region_cache);
resv_map->region_cache_count = 1;
return resv_map;
}
void resv_map_release(struct kref *ref)
{
struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
struct list_head *head = &resv_map->region_cache;
struct file_region *rg, *trg;
/* Clear out any active regions before we release the map. */
region_del(resv_map, 0, LONG_MAX);
/* ... and any entries left in the cache */
list_for_each_entry_safe(rg, trg, head, link) {
list_del(&rg->link);
kfree(rg);
}
VM_BUG_ON(resv_map->adds_in_progress);
kfree(resv_map);
}
static inline struct resv_map *inode_resv_map(struct inode *inode)
{
/*
* At inode evict time, i_mapping may not point to the original
* address space within the inode. This original address space
* contains the pointer to the resv_map. So, always use the
* address space embedded within the inode.
* The VERY common case is inode->mapping == &inode->i_data but,
* this may not be true for device special inodes.
*/
return (struct resv_map *)(&inode->i_data)->i_private_data;
}
static struct resv_map *vma_resv_map(struct vm_area_struct *vma)
{
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
if (vma->vm_flags & VM_MAYSHARE) {
struct address_space *mapping = vma->vm_file->f_mapping;
struct inode *inode = mapping->host;
return inode_resv_map(inode);
} else {
return (struct resv_map *)(get_vma_private_data(vma) &
~HPAGE_RESV_MASK);
}
}
static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map)
{
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma);
set_vma_private_data(vma, (unsigned long)map);
}
static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags)
{
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma);
set_vma_private_data(vma, get_vma_private_data(vma) | flags);
}
static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag)
{
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
return (get_vma_private_data(vma) & flag) != 0;
}
bool __vma_private_lock(struct vm_area_struct *vma)
{
return !(vma->vm_flags & VM_MAYSHARE) &&
get_vma_private_data(vma) & ~HPAGE_RESV_MASK &&
is_vma_resv_set(vma, HPAGE_RESV_OWNER);
}
void hugetlb_dup_vma_private(struct vm_area_struct *vma)
{
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
/*
* Clear vm_private_data
* - For shared mappings this is a per-vma semaphore that may be
* allocated in a subsequent call to hugetlb_vm_op_open.
* Before clearing, make sure pointer is not associated with vma
* as this will leak the structure. This is the case when called
* via clear_vma_resv_huge_pages() and hugetlb_vm_op_open has already
* been called to allocate a new structure.
* - For MAP_PRIVATE mappings, this is the reserve map which does
* not apply to children. Faults generated by the children are
* not guaranteed to succeed, even if read-only.
*/
if (vma->vm_flags & VM_MAYSHARE) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
if (vma_lock && vma_lock->vma != vma)
vma->vm_private_data = NULL;
} else
vma->vm_private_data = NULL;
}
/*
* Reset and decrement one ref on hugepage private reservation.
* Called with mm->mmap_lock writer semaphore held.
* This function should be only used by move_vma() and operate on
* same sized vma. It should never come here with last ref on the
* reservation.
*/
void clear_vma_resv_huge_pages(struct vm_area_struct *vma)
{
/*
* Clear the old hugetlb private page reservation.
* It has already been transferred to new_vma.
*
* During a mremap() operation of a hugetlb vma we call move_vma()
* which copies vma into new_vma and unmaps vma. After the copy
* operation both new_vma and vma share a reference to the resv_map
* struct, and at that point vma is about to be unmapped. We don't
* want to return the reservation to the pool at unmap of vma because
* the reservation still lives on in new_vma, so simply decrement the
* ref here and remove the resv_map reference from this vma.
*/
struct resv_map *reservations = vma_resv_map(vma);
if (reservations && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
resv_map_put_hugetlb_cgroup_uncharge_info(reservations);
kref_put(&reservations->refs, resv_map_release);
}
hugetlb_dup_vma_private(vma);
}
/* Returns true if the VMA has associated reserve pages */
static bool vma_has_reserves(struct vm_area_struct *vma, long chg)
{
if (vma->vm_flags & VM_NORESERVE) {
/*
* This address is already reserved by other process(chg == 0),
* so, we should decrement reserved count. Without decrementing,
* reserve count remains after releasing inode, because this
* allocated page will go into page cache and is regarded as
* coming from reserved pool in releasing step. Currently, we
* don't have any other solution to deal with this situation
* properly, so add work-around here.
*/
if (vma->vm_flags & VM_MAYSHARE && chg == 0)
return true;
else
return false;
}
/* Shared mappings always use reserves */
if (vma->vm_flags & VM_MAYSHARE) {
/*
* We know VM_NORESERVE is not set. Therefore, there SHOULD
* be a region map for all pages. The only situation where
* there is no region map is if a hole was punched via
* fallocate. In this case, there really are no reserves to
* use. This situation is indicated if chg != 0.
*/
if (chg)
return false;
else
return true;
}
/*
* Only the process that called mmap() has reserves for
* private mappings.
*/
if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
/*
* Like the shared case above, a hole punch or truncate
* could have been performed on the private mapping.
* Examine the value of chg to determine if reserves
* actually exist or were previously consumed.
* Very Subtle - The value of chg comes from a previous
* call to vma_needs_reserves(). The reserve map for
* private mappings has different (opposite) semantics
* than that of shared mappings. vma_needs_reserves()
* has already taken this difference in semantics into
* account. Therefore, the meaning of chg is the same
* as in the shared case above. Code could easily be
* combined, but keeping it separate draws attention to
* subtle differences.
*/
if (chg)
return false;
else
return true;
}
return false;
}
static void enqueue_hugetlb_folio(struct hstate *h, struct folio *folio)
{
int nid = folio_nid(folio);
lockdep_assert_held(&hugetlb_lock);
VM_BUG_ON_FOLIO(folio_ref_count(folio), folio);
list_move(&folio->lru, &h->hugepage_freelists[nid]);
h->free_huge_pages++;
h->free_huge_pages_node[nid]++;
folio_set_hugetlb_freed(folio);
}
static struct folio *dequeue_hugetlb_folio_node_exact(struct hstate *h,
int nid)
{
struct folio *folio;
bool pin = !!(current->flags & PF_MEMALLOC_PIN);
lockdep_assert_held(&hugetlb_lock);
list_for_each_entry(folio, &h->hugepage_freelists[nid], lru) {
if (pin && !folio_is_longterm_pinnable(folio))
continue;
if (folio_test_hwpoison(folio))
continue;
list_move(&folio->lru, &h->hugepage_activelist);
folio_ref_unfreeze(folio, 1);
folio_clear_hugetlb_freed(folio);
h->free_huge_pages--;
h->free_huge_pages_node[nid]--;
return folio;
}
return NULL;
}
static struct folio *dequeue_hugetlb_folio_nodemask(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nmask)
{
unsigned int cpuset_mems_cookie;
struct zonelist *zonelist;
struct zone *zone;
struct zoneref *z;
int node = NUMA_NO_NODE;
zonelist = node_zonelist(nid, gfp_mask);
retry_cpuset:
cpuset_mems_cookie = read_mems_allowed_begin();
for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) {
struct folio *folio;
if (!cpuset_zone_allowed(zone, gfp_mask))
continue;
/*
* no need to ask again on the same node. Pool is node rather than
* zone aware
*/
if (zone_to_nid(zone) == node)
continue;
node = zone_to_nid(zone);
folio = dequeue_hugetlb_folio_node_exact(h, node);
if (folio)
return folio;
}
if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
return NULL;
}
static unsigned long available_huge_pages(struct hstate *h)
{
return h->free_huge_pages - h->resv_huge_pages;
}
static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h,
struct vm_area_struct *vma,
unsigned long address, int avoid_reserve,
long chg)
{
struct folio *folio = NULL;
struct mempolicy *mpol;
gfp_t gfp_mask;
nodemask_t *nodemask;
int nid;
/*
* A child process with MAP_PRIVATE mappings created by their parent
* have no page reserves. This check ensures that reservations are
* not "stolen". The child may still get SIGKILLed
*/
if (!vma_has_reserves(vma, chg) && !available_huge_pages(h))
goto err;
/* If reserves cannot be used, ensure enough pages are in the pool */
if (avoid_reserve && !available_huge_pages(h))
goto err;
gfp_mask = htlb_alloc_mask(h);
nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask);
if (mpol_is_preferred_many(mpol)) {
folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask,
nid, nodemask);
/* Fallback to all nodes if page==NULL */
nodemask = NULL;
}
if (!folio)
folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask,
nid, nodemask);
if (folio && !avoid_reserve && vma_has_reserves(vma, chg)) {
folio_set_hugetlb_restore_reserve(folio);
h->resv_huge_pages--;
}
mpol_cond_put(mpol);
return folio;
err:
return NULL;
}
/*
* common helper functions for hstate_next_node_to_{alloc|free}.
* We may have allocated or freed a huge page based on a different
* nodes_allowed previously, so h->next_node_to_{alloc|free} might
* be outside of *nodes_allowed. Ensure that we use an allowed
* node for alloc or free.
*/
static int next_node_allowed(int nid, nodemask_t *nodes_allowed)
{
nid = next_node_in(nid, *nodes_allowed);
VM_BUG_ON(nid >= MAX_NUMNODES);
return nid;
}
static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed)
{
if (!node_isset(nid, *nodes_allowed))
nid = next_node_allowed(nid, nodes_allowed);
return nid;
}
/*
* returns the previously saved node ["this node"] from which to
* allocate a persistent huge page for the pool and advance the
* next node from which to allocate, handling wrap at end of node
* mask.
*/
static int hstate_next_node_to_alloc(int *next_node,
nodemask_t *nodes_allowed)
{
int nid;
VM_BUG_ON(!nodes_allowed);
nid = get_valid_node_allowed(*next_node, nodes_allowed);
*next_node = next_node_allowed(nid, nodes_allowed);
return nid;
}
/*
* helper for remove_pool_hugetlb_folio() - return the previously saved
* node ["this node"] from which to free a huge page. Advance the
* next node id whether or not we find a free huge page to free so
* that the next attempt to free addresses the next node.
*/
static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
{
int nid;
VM_BUG_ON(!nodes_allowed);
nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed);
h->next_nid_to_free = next_node_allowed(nid, nodes_allowed);
return nid;
}
#define for_each_node_mask_to_alloc(next_node, nr_nodes, node, mask) \
for (nr_nodes = nodes_weight(*mask); \
nr_nodes > 0 && \
((node = hstate_next_node_to_alloc(next_node, mask)) || 1); \
nr_nodes--)
#define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \
for (nr_nodes = nodes_weight(*mask); \
nr_nodes > 0 && \
((node = hstate_next_node_to_free(hs, mask)) || 1); \
nr_nodes--)
/* used to demote non-gigantic_huge pages as well */
static void __destroy_compound_gigantic_folio(struct folio *folio,
unsigned int order, bool demote)
{
int i;
int nr_pages = 1 << order;
struct page *p;
atomic_set(&folio->_entire_mapcount, 0);
atomic_set(&folio->_nr_pages_mapped, 0);
atomic_set(&folio->_pincount, 0);
for (i = 1; i < nr_pages; i++) {
p = folio_page(folio, i);
p->flags &= ~PAGE_FLAGS_CHECK_AT_FREE;
p->mapping = NULL;
clear_compound_head(p);
if (!demote)
set_page_refcounted(p);
}
__folio_clear_head(folio);
}
static void destroy_compound_hugetlb_folio_for_demote(struct folio *folio,
unsigned int order)
{
__destroy_compound_gigantic_folio(folio, order, true);
}
#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
static void destroy_compound_gigantic_folio(struct folio *folio,
unsigned int order)
{
__destroy_compound_gigantic_folio(folio, order, false);
}
static void free_gigantic_folio(struct folio *folio, unsigned int order)
{
/*
* If the page isn't allocated using the cma allocator,
* cma_release() returns false.
*/
#ifdef CONFIG_CMA
int nid = folio_nid(folio);
if (cma_release(hugetlb_cma[nid], &folio->page, 1 << order))
return;
#endif
free_contig_range(folio_pfn(folio), 1 << order);
}
#ifdef CONFIG_CONTIG_ALLOC
static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nodemask)
{
struct page *page;
unsigned long nr_pages = pages_per_huge_page(h);
if (nid == NUMA_NO_NODE)
nid = numa_mem_id();
#ifdef CONFIG_CMA
{
int node;
if (hugetlb_cma[nid]) {
page = cma_alloc(hugetlb_cma[nid], nr_pages,
huge_page_order(h), true);
if (page)
return page_folio(page);
}
if (!(gfp_mask & __GFP_THISNODE)) {
for_each_node_mask(node, *nodemask) {
if (node == nid || !hugetlb_cma[node])
continue;
page = cma_alloc(hugetlb_cma[node], nr_pages,
huge_page_order(h), true);
if (page)
return page_folio(page);
}
}
}
#endif
page = alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask);
return page ? page_folio(page) : NULL;
}
#else /* !CONFIG_CONTIG_ALLOC */
static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nodemask)
{
return NULL;
}
#endif /* CONFIG_CONTIG_ALLOC */
#else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
static struct folio *alloc_gigantic_folio(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nodemask)
{
return NULL;
}
static inline void free_gigantic_folio(struct folio *folio,
unsigned int order) { }
static inline void destroy_compound_gigantic_folio(struct folio *folio,
unsigned int order) { }
#endif
static inline void __clear_hugetlb_destructor(struct hstate *h,
struct folio *folio)
{
lockdep_assert_held(&hugetlb_lock);
folio_clear_hugetlb(folio);
}
/*
* Remove hugetlb folio from lists.
* If vmemmap exists for the folio, update dtor so that the folio appears
* as just a compound page. Otherwise, wait until after allocating vmemmap
* to update dtor.
*
* A reference is held on the folio, except in the case of demote.
*
* Must be called with hugetlb lock held.
*/
static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
bool adjust_surplus,
bool demote)
{
int nid = folio_nid(folio);
VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio(folio), folio);
VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio_rsvd(folio), folio);
lockdep_assert_held(&hugetlb_lock);
if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
return;
list_del(&folio->lru);
if (folio_test_hugetlb_freed(folio)) {
h->free_huge_pages--;
h->free_huge_pages_node[nid]--;
}
if (adjust_surplus) {
h->surplus_huge_pages--;
h->surplus_huge_pages_node[nid]--;
}
/*
* We can only clear the hugetlb destructor after allocating vmemmap
* pages. Otherwise, someone (memory error handling) may try to write
* to tail struct pages.
*/
if (!folio_test_hugetlb_vmemmap_optimized(folio))
__clear_hugetlb_destructor(h, folio);
/*
* In the case of demote we do not ref count the page as it will soon
* be turned into a page of smaller size.
*/
if (!demote)
folio_ref_unfreeze(folio, 1);
h->nr_huge_pages--;
h->nr_huge_pages_node[nid]--;
}
static void remove_hugetlb_folio(struct hstate *h, struct folio *folio,
bool adjust_surplus)
{
__remove_hugetlb_folio(h, folio, adjust_surplus, false);
}
static void remove_hugetlb_folio_for_demote(struct hstate *h, struct folio *folio,
bool adjust_surplus)
{
__remove_hugetlb_folio(h, folio, adjust_surplus, true);
}
static void add_hugetlb_folio(struct hstate *h, struct folio *folio,
bool adjust_surplus)
{
int zeroed;
int nid = folio_nid(folio);
VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio);
lockdep_assert_held(&hugetlb_lock);
INIT_LIST_HEAD(&folio->lru);
h->nr_huge_pages++;
h->nr_huge_pages_node[nid]++;
if (adjust_surplus) {
h->surplus_huge_pages++;
h->surplus_huge_pages_node[nid]++;
}
folio_set_hugetlb(folio);
folio_change_private(folio, NULL);
/*
* We have to set hugetlb_vmemmap_optimized again as above
* folio_change_private(folio, NULL) cleared it.
*/
folio_set_hugetlb_vmemmap_optimized(folio);
/*
* This folio is about to be managed by the hugetlb allocator and
* should have no users. Drop our reference, and check for others
* just in case.
*/
zeroed = folio_put_testzero(folio);
if (unlikely(!zeroed))
/*
* It is VERY unlikely soneone else has taken a ref
* on the folio. In this case, we simply return as
* free_huge_folio() will be called when this other ref
* is dropped.
*/
return;
arch_clear_hugepage_flags(&folio->page);
enqueue_hugetlb_folio(h, folio);
}
static void __update_and_free_hugetlb_folio(struct hstate *h,
struct folio *folio)
{
bool clear_dtor = folio_test_hugetlb_vmemmap_optimized(folio);
if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
return;
/*
* If we don't know which subpages are hwpoisoned, we can't free
* the hugepage, so it's leaked intentionally.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
return;
/*
* If folio is not vmemmap optimized (!clear_dtor), then the folio
* is no longer identified as a hugetlb page. hugetlb_vmemmap_restore_folio
* can only be passed hugetlb pages and will BUG otherwise.
*/
if (clear_dtor && hugetlb_vmemmap_restore_folio(h, folio)) {
spin_lock_irq(&hugetlb_lock);
/*
* If we cannot allocate vmemmap pages, just refuse to free the
* page and put the page back on the hugetlb free list and treat
* as a surplus page.
*/
add_hugetlb_folio(h, folio, true);
spin_unlock_irq(&hugetlb_lock);
return;
}
/*
* Move PageHWPoison flag from head page to the raw error pages,
* which makes any healthy subpages reusable.
*/
if (unlikely(folio_test_hwpoison(folio)))
folio_clear_hugetlb_hwpoison(folio);
/*
* If vmemmap pages were allocated above, then we need to clear the
* hugetlb destructor under the hugetlb lock.
*/
if (clear_dtor) {
spin_lock_irq(&hugetlb_lock);
__clear_hugetlb_destructor(h, folio);
spin_unlock_irq(&hugetlb_lock);
}
/*
* Non-gigantic pages demoted from CMA allocated gigantic pages
* need to be given back to CMA in free_gigantic_folio.
*/
if (hstate_is_gigantic(h) ||
hugetlb_cma_folio(folio, huge_page_order(h))) {
destroy_compound_gigantic_folio(folio, huge_page_order(h));
free_gigantic_folio(folio, huge_page_order(h));
} else {
__free_pages(&folio->page, huge_page_order(h));
}
}
/*
* As update_and_free_hugetlb_folio() can be called under any context, so we cannot
* use GFP_KERNEL to allocate vmemmap pages. However, we can defer the
* actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate
* the vmemmap pages.
*
* free_hpage_workfn() locklessly retrieves the linked list of pages to be
* freed and frees them one-by-one. As the page->mapping pointer is going
* to be cleared in free_hpage_workfn() anyway, it is reused as the llist_node
* structure of a lockless linked list of huge pages to be freed.
*/
static LLIST_HEAD(hpage_freelist);
static void free_hpage_workfn(struct work_struct *work)
{
struct llist_node *node;
node = llist_del_all(&hpage_freelist);
while (node) {
struct folio *folio;
struct hstate *h;
folio = container_of((struct address_space **)node,
struct folio, mapping);
node = node->next;
folio->mapping = NULL;
/*
* The VM_BUG_ON_FOLIO(!folio_test_hugetlb(folio), folio) in
* folio_hstate() is going to trigger because a previous call to
* remove_hugetlb_folio() will clear the hugetlb bit, so do
* not use folio_hstate() directly.
*/
h = size_to_hstate(folio_size(folio));
__update_and_free_hugetlb_folio(h, folio);
cond_resched();
}
}
static DECLARE_WORK(free_hpage_work, free_hpage_workfn);
static inline void flush_free_hpage_work(struct hstate *h)
{
if (hugetlb_vmemmap_optimizable(h))
flush_work(&free_hpage_work);
}
static void update_and_free_hugetlb_folio(struct hstate *h, struct folio *folio,
bool atomic)
{
if (!folio_test_hugetlb_vmemmap_optimized(folio) || !atomic) {
__update_and_free_hugetlb_folio(h, folio);
return;
}
/*
* Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap pages.
*
* Only call schedule_work() if hpage_freelist is previously
* empty. Otherwise, schedule_work() had been called but the workfn
* hasn't retrieved the list yet.
*/
if (llist_add((struct llist_node *)&folio->mapping, &hpage_freelist))
schedule_work(&free_hpage_work);
}
static void bulk_vmemmap_restore_error(struct hstate *h,
struct list_head *folio_list,
struct list_head *non_hvo_folios)
{
struct folio *folio, *t_folio;
if (!list_empty(non_hvo_folios)) {
/*
* Free any restored hugetlb pages so that restore of the
* entire list can be retried.
* The idea is that in the common case of ENOMEM errors freeing
* hugetlb pages with vmemmap we will free up memory so that we
* can allocate vmemmap for more hugetlb pages.
*/
list_for_each_entry_safe(folio, t_folio, non_hvo_folios, lru) {
list_del(&folio->lru);
spin_lock_irq(&hugetlb_lock);
__clear_hugetlb_destructor(h, folio);
spin_unlock_irq(&hugetlb_lock);
update_and_free_hugetlb_folio(h, folio, false);
cond_resched();
}
} else {
/*
* In the case where there are no folios which can be
* immediately freed, we loop through the list trying to restore
* vmemmap individually in the hope that someone elsewhere may
* have done something to cause success (such as freeing some
* memory). If unable to restore a hugetlb page, the hugetlb
* page is made a surplus page and removed from the list.
* If are able to restore vmemmap and free one hugetlb page, we
* quit processing the list to retry the bulk operation.
*/
list_for_each_entry_safe(folio, t_folio, folio_list, lru)
if (hugetlb_vmemmap_restore_folio(h, folio)) {
list_del(&folio->lru);
spin_lock_irq(&hugetlb_lock);
add_hugetlb_folio(h, folio, true);
spin_unlock_irq(&hugetlb_lock);
} else {
list_del(&folio->lru);
spin_lock_irq(&hugetlb_lock);
__clear_hugetlb_destructor(h, folio);
spin_unlock_irq(&hugetlb_lock);
update_and_free_hugetlb_folio(h, folio, false);
cond_resched();
break;
}
}
}
static void update_and_free_pages_bulk(struct hstate *h,
struct list_head *folio_list)
{
long ret;
struct folio *folio, *t_folio;
LIST_HEAD(non_hvo_folios);
/*
* First allocate required vmemmmap (if necessary) for all folios.
* Carefully handle errors and free up any available hugetlb pages
* in an effort to make forward progress.
*/
retry:
ret = hugetlb_vmemmap_restore_folios(h, folio_list, &non_hvo_folios);
if (ret < 0) {
bulk_vmemmap_restore_error(h, folio_list, &non_hvo_folios);
goto retry;
}
/*
* At this point, list should be empty, ret should be >= 0 and there
* should only be pages on the non_hvo_folios list.
* Do note that the non_hvo_folios list could be empty.
* Without HVO enabled, ret will be 0 and there is no need to call
* __clear_hugetlb_destructor as this was done previously.
*/
VM_WARN_ON(!list_empty(folio_list));
VM_WARN_ON(ret < 0);
if (!list_empty(&non_hvo_folios) && ret) {
spin_lock_irq(&hugetlb_lock);
list_for_each_entry(folio, &non_hvo_folios, lru)
__clear_hugetlb_destructor(h, folio);
spin_unlock_irq(&hugetlb_lock);
}
list_for_each_entry_safe(folio, t_folio, &non_hvo_folios, lru) {
update_and_free_hugetlb_folio(h, folio, false);
cond_resched();
}
}
struct hstate *size_to_hstate(unsigned long size)
{
struct hstate *h;
for_each_hstate(h) {
if (huge_page_size(h) == size)
return h;
}
return NULL;
}
void free_huge_folio(struct folio *folio)
{
/*
* Can't pass hstate in here because it is called from the
* compound page destructor.
*/
struct hstate *h = folio_hstate(folio);
int nid = folio_nid(folio);
struct hugepage_subpool *spool = hugetlb_folio_subpool(folio);
bool restore_reserve;
unsigned long flags;
VM_BUG_ON_FOLIO(folio_ref_count(folio), folio);
VM_BUG_ON_FOLIO(folio_mapcount(folio), folio);
hugetlb_set_folio_subpool(folio, NULL);
if (folio_test_anon(folio))
__ClearPageAnonExclusive(&folio->page);
folio->mapping = NULL;
restore_reserve = folio_test_hugetlb_restore_reserve(folio);
folio_clear_hugetlb_restore_reserve(folio);
/*
* If HPageRestoreReserve was set on page, page allocation consumed a
* reservation. If the page was associated with a subpool, there
* would have been a page reserved in the subpool before allocation
* via hugepage_subpool_get_pages(). Since we are 'restoring' the
* reservation, do not call hugepage_subpool_put_pages() as this will
* remove the reserved page from the subpool.
*/
if (!restore_reserve) {
/*
* A return code of zero implies that the subpool will be
* under its minimum size if the reservation is not restored
* after page is free. Therefore, force restore_reserve
* operation.
*/
if (hugepage_subpool_put_pages(spool, 1) == 0)
restore_reserve = true;
}
spin_lock_irqsave(&hugetlb_lock, flags);
folio_clear_hugetlb_migratable(folio);
hugetlb_cgroup_uncharge_folio(hstate_index(h),
pages_per_huge_page(h), folio);
hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h),
pages_per_huge_page(h), folio);
mem_cgroup_uncharge(folio);
if (restore_reserve)
h->resv_huge_pages++;
if (folio_test_hugetlb_temporary(folio)) {
remove_hugetlb_folio(h, folio, false);
spin_unlock_irqrestore(&hugetlb_lock, flags);
update_and_free_hugetlb_folio(h, folio, true);
} else if (h->surplus_huge_pages_node[nid]) {
/* remove the page from active list */
remove_hugetlb_folio(h, folio, true);
spin_unlock_irqrestore(&hugetlb_lock, flags);
update_and_free_hugetlb_folio(h, folio, true);
} else {
arch_clear_hugepage_flags(&folio->page);
enqueue_hugetlb_folio(h, folio);
spin_unlock_irqrestore(&hugetlb_lock, flags);
}
}
/*
* Must be called with the hugetlb lock held
*/
static void __prep_account_new_huge_page(struct hstate *h, int nid)
{
lockdep_assert_held(&hugetlb_lock);
h->nr_huge_pages++;
h->nr_huge_pages_node[nid]++;
}
static void init_new_hugetlb_folio(struct hstate *h, struct folio *folio)
{
folio_set_hugetlb(folio);
INIT_LIST_HEAD(&folio->lru);
hugetlb_set_folio_subpool(folio, NULL);
set_hugetlb_cgroup(folio, NULL);
set_hugetlb_cgroup_rsvd(folio, NULL);
}
static void __prep_new_hugetlb_folio(struct hstate *h, struct folio *folio)
{
init_new_hugetlb_folio(h, folio);
hugetlb_vmemmap_optimize_folio(h, folio);
}
static void prep_new_hugetlb_folio(struct hstate *h, struct folio *folio, int nid)
{
__prep_new_hugetlb_folio(h, folio);
spin_lock_irq(&hugetlb_lock);
__prep_account_new_huge_page(h, nid);
spin_unlock_irq(&hugetlb_lock);
}
static bool __prep_compound_gigantic_folio(struct folio *folio,
unsigned int order, bool demote)
{
int i, j;
int nr_pages = 1 << order;
struct page *p;
__folio_clear_reserved(folio);
for (i = 0; i < nr_pages; i++) {
p = folio_page(folio, i);
/*
* For gigantic hugepages allocated through bootmem at
* boot, it's safer to be consistent with the not-gigantic
* hugepages and clear the PG_reserved bit from all tail pages
* too. Otherwise drivers using get_user_pages() to access tail
* pages may get the reference counting wrong if they see
* PG_reserved set on a tail page (despite the head page not
* having PG_reserved set). Enforcing this consistency between
* head and tail pages allows drivers to optimize away a check
* on the head page when they need know if put_page() is needed
* after get_user_pages().
*/
if (i != 0) /* head page cleared above */
__ClearPageReserved(p);
/*
* Subtle and very unlikely
*
* Gigantic 'page allocators' such as memblock or cma will
* return a set of pages with each page ref counted. We need
* to turn this set of pages into a compound page with tail
* page ref counts set to zero. Code such as speculative page
* cache adding could take a ref on a 'to be' tail page.
* We need to respect any increased ref count, and only set
* the ref count to zero if count is currently 1. If count
* is not 1, we return an error. An error return indicates
* the set of pages can not be converted to a gigantic page.
* The caller who allocated the pages should then discard the
* pages using the appropriate free interface.
*
* In the case of demote, the ref count will be zero.
*/
if (!demote) {
if (!page_ref_freeze(p, 1)) {
pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n");
goto out_error;
}
} else {
VM_BUG_ON_PAGE(page_count(p), p);
}
if (i != 0)
set_compound_head(p, &folio->page);
}
__folio_set_head(folio);
/* we rely on prep_new_hugetlb_folio to set the destructor */
folio_set_order(folio, order);
atomic_set(&folio->_entire_mapcount, -1);
atomic_set(&folio->_nr_pages_mapped, 0);
atomic_set(&folio->_pincount, 0);
return true;
out_error:
/* undo page modifications made above */
for (j = 0; j < i; j++) {
p = folio_page(folio, j);
if (j != 0)
clear_compound_head(p);
set_page_refcounted(p);
}
/* need to clear PG_reserved on remaining tail pages */
for (; j < nr_pages; j++) {
p = folio_page(folio, j);
__ClearPageReserved(p);
}
return false;
}
static bool prep_compound_gigantic_folio(struct folio *folio,
unsigned int order)
{
return __prep_compound_gigantic_folio(folio, order, false);
}
static bool prep_compound_gigantic_folio_for_demote(struct folio *folio,
unsigned int order)
{
return __prep_compound_gigantic_folio(folio, order, true);
}
/*
* PageHuge() only returns true for hugetlbfs pages, but not for normal or
* transparent huge pages. See the PageTransHuge() documentation for more
* details.
*/
int PageHuge(struct page *page)
{
struct folio *folio;
if (!PageCompound(page))
return 0;
folio = page_folio(page);
return folio_test_hugetlb(folio);
}
EXPORT_SYMBOL_GPL(PageHuge);
/*
* Find and lock address space (mapping) in write mode.
*
* Upon entry, the page is locked which means that page_mapping() is
* stable. Due to locking order, we can only trylock_write. If we can
* not get the lock, simply return NULL to caller.
*/
struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage)
{
struct address_space *mapping = page_mapping(hpage);
if (!mapping)
return mapping;
if (i_mmap_trylock_write(mapping))
return mapping;
return NULL;
}
static struct folio *alloc_buddy_hugetlb_folio(struct hstate *h,
gfp_t gfp_mask, int nid, nodemask_t *nmask,
nodemask_t *node_alloc_noretry)
{
int order = huge_page_order(h);
struct page *page;
bool alloc_try_hard = true;
bool retry = true;
/*
* By default we always try hard to allocate the page with
* __GFP_RETRY_MAYFAIL flag. However, if we are allocating pages in
* a loop (to adjust global huge page counts) and previous allocation
* failed, do not continue to try hard on the same node. Use the
* node_alloc_noretry bitmap to manage this state information.
*/
if (node_alloc_noretry && node_isset(nid, *node_alloc_noretry))
alloc_try_hard = false;
gfp_mask |= __GFP_COMP|__GFP_NOWARN;
if (alloc_try_hard)
gfp_mask |= __GFP_RETRY_MAYFAIL;
if (nid == NUMA_NO_NODE)
nid = numa_mem_id();
retry:
page = __alloc_pages(gfp_mask, order, nid, nmask);
/* Freeze head page */
if (page && !page_ref_freeze(page, 1)) {
__free_pages(page, order);
if (retry) { /* retry once */
retry = false;
goto retry;
}
/* WOW! twice in a row. */
pr_warn("HugeTLB head page unexpected inflated ref count\n");
page = NULL;
}
/*
* If we did not specify __GFP_RETRY_MAYFAIL, but still got a page this
* indicates an overall state change. Clear bit so that we resume
* normal 'try hard' allocations.
*/
if (node_alloc_noretry && page && !alloc_try_hard)
node_clear(nid, *node_alloc_noretry);
/*
* If we tried hard to get a page but failed, set bit so that
* subsequent attempts will not try as hard until there is an
* overall state change.
*/
if (node_alloc_noretry && !page && alloc_try_hard)
node_set(nid, *node_alloc_noretry);
if (!page) {
__count_vm_event(HTLB_BUDDY_PGALLOC_FAIL);
return NULL;
}
__count_vm_event(HTLB_BUDDY_PGALLOC);
return page_folio(page);
}
static struct folio *__alloc_fresh_hugetlb_folio(struct hstate *h,
gfp_t gfp_mask, int nid, nodemask_t *nmask,
nodemask_t *node_alloc_noretry)
{
struct folio *folio;
bool retry = false;
retry:
if (hstate_is_gigantic(h))
folio = alloc_gigantic_folio(h, gfp_mask, nid, nmask);
else
folio = alloc_buddy_hugetlb_folio(h, gfp_mask,
nid, nmask, node_alloc_noretry);
if (!folio)
return NULL;
if (hstate_is_gigantic(h)) {
if (!prep_compound_gigantic_folio(folio, huge_page_order(h))) {
/*
* Rare failure to convert pages to compound page.
* Free pages and try again - ONCE!
*/
free_gigantic_folio(folio, huge_page_order(h));
if (!retry) {
retry = true;
goto retry;
}
return NULL;
}
}
return folio;
}
static struct folio *only_alloc_fresh_hugetlb_folio(struct hstate *h,
gfp_t gfp_mask, int nid, nodemask_t *nmask,
nodemask_t *node_alloc_noretry)
{
struct folio *folio;
folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask,
node_alloc_noretry);
if (folio)
init_new_hugetlb_folio(h, folio);
return folio;
}
/*
* Common helper to allocate a fresh hugetlb page. All specific allocators
* should use this function to get new hugetlb pages
*
* Note that returned page is 'frozen': ref count of head page and all tail
* pages is zero.
*/
static struct folio *alloc_fresh_hugetlb_folio(struct hstate *h,
gfp_t gfp_mask, int nid, nodemask_t *nmask,
nodemask_t *node_alloc_noretry)
{
struct folio *folio;
folio = __alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask,
node_alloc_noretry);
if (!folio)
return NULL;
prep_new_hugetlb_folio(h, folio, folio_nid(folio));
return folio;
}
static void prep_and_add_allocated_folios(struct hstate *h,
struct list_head *folio_list)
{
unsigned long flags;
struct folio *folio, *tmp_f;
/* Send list for bulk vmemmap optimization processing */
hugetlb_vmemmap_optimize_folios(h, folio_list);
/* Add all new pool pages to free lists in one lock cycle */
spin_lock_irqsave(&hugetlb_lock, flags);
list_for_each_entry_safe(folio, tmp_f, folio_list, lru) {
__prep_account_new_huge_page(h, folio_nid(folio));
enqueue_hugetlb_folio(h, folio);
}
spin_unlock_irqrestore(&hugetlb_lock, flags);
}
/*
* Allocates a fresh hugetlb page in a node interleaved manner. The page
* will later be added to the appropriate hugetlb pool.
*/
static struct folio *alloc_pool_huge_folio(struct hstate *h,
nodemask_t *nodes_allowed,
nodemask_t *node_alloc_noretry,
int *next_node)
{
gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
int nr_nodes, node;
for_each_node_mask_to_alloc(next_node, nr_nodes, node, nodes_allowed) {
struct folio *folio;
folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, node,
nodes_allowed, node_alloc_noretry);
if (folio)
return folio;
}
return NULL;
}
/*
* Remove huge page from pool from next node to free. Attempt to keep
* persistent huge pages more or less balanced over allowed nodes.
* This routine only 'removes' the hugetlb page. The caller must make
* an additional call to free the page to low level allocators.
* Called with hugetlb_lock locked.
*/
static struct folio *remove_pool_hugetlb_folio(struct hstate *h,
nodemask_t *nodes_allowed, bool acct_surplus)
{
int nr_nodes, node;
struct folio *folio = NULL;
lockdep_assert_held(&hugetlb_lock);
for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) {
/*
* If we're returning unused surplus pages, only examine
* nodes with surplus pages.
*/
if ((!acct_surplus || h->surplus_huge_pages_node[node]) &&
!list_empty(&h->hugepage_freelists[node])) {
folio = list_entry(h->hugepage_freelists[node].next,
struct folio, lru);
remove_hugetlb_folio(h, folio, acct_surplus);
break;
}
}
return folio;
}
/*
* Dissolve a given free hugepage into free buddy pages. This function does
* nothing for in-use hugepages and non-hugepages.
* This function returns values like below:
*
* -ENOMEM: failed to allocate vmemmap pages to free the freed hugepages
* when the system is under memory pressure and the feature of
* freeing unused vmemmap pages associated with each hugetlb page
* is enabled.
* -EBUSY: failed to dissolved free hugepages or the hugepage is in-use
* (allocated or reserved.)
* 0: successfully dissolved free hugepages or the page is not a
* hugepage (considered as already dissolved)
*/
int dissolve_free_huge_page(struct page *page)
{
int rc = -EBUSY;
struct folio *folio = page_folio(page);
retry:
/* Not to disrupt normal path by vainly holding hugetlb_lock */
if (!folio_test_hugetlb(folio))
return 0;
spin_lock_irq(&hugetlb_lock);
if (!folio_test_hugetlb(folio)) {
rc = 0;
goto out;
}
if (!folio_ref_count(folio)) {
struct hstate *h = folio_hstate(folio);
if (!available_huge_pages(h))
goto out;
/*
* We should make sure that the page is already on the free list
* when it is dissolved.
*/
if (unlikely(!folio_test_hugetlb_freed(folio))) {
spin_unlock_irq(&hugetlb_lock);
cond_resched();
/*
* Theoretically, we should return -EBUSY when we
* encounter this race. In fact, we have a chance
* to successfully dissolve the page if we do a
* retry. Because the race window is quite small.
* If we seize this opportunity, it is an optimization
* for increasing the success rate of dissolving page.
*/
goto retry;
}
remove_hugetlb_folio(h, folio, false);
h->max_huge_pages--;
spin_unlock_irq(&hugetlb_lock);
/*
* Normally update_and_free_hugtlb_folio will allocate required vmemmmap
* before freeing the page. update_and_free_hugtlb_folio will fail to
* free the page if it can not allocate required vmemmap. We
* need to adjust max_huge_pages if the page is not freed.
* Attempt to allocate vmemmmap here so that we can take
* appropriate action on failure.
*
* The folio_test_hugetlb check here is because
* remove_hugetlb_folio will clear hugetlb folio flag for
* non-vmemmap optimized hugetlb folios.
*/
if (folio_test_hugetlb(folio)) {
rc = hugetlb_vmemmap_restore_folio(h, folio);
if (rc) {
spin_lock_irq(&hugetlb_lock);
add_hugetlb_folio(h, folio, false);
h->max_huge_pages++;
goto out;
}
} else
rc = 0;
update_and_free_hugetlb_folio(h, folio, false);
return rc;
}
out:
spin_unlock_irq(&hugetlb_lock);
return rc;
}
/*
* Dissolve free hugepages in a given pfn range. Used by memory hotplug to
* make specified memory blocks removable from the system.
* Note that this will dissolve a free gigantic hugepage completely, if any
* part of it lies within the given range.
* Also note that if dissolve_free_huge_page() returns with an error, all
* free hugepages that were dissolved before that error are lost.
*/
int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct page *page;
int rc = 0;
unsigned int order;
struct hstate *h;
if (!hugepages_supported())
return rc;
order = huge_page_order(&default_hstate);
for_each_hstate(h)
order = min(order, huge_page_order(h));
for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order) {
page = pfn_to_page(pfn);
rc = dissolve_free_huge_page(page);
if (rc)
break;
}
return rc;
}
/*
* Allocates a fresh surplus page from the page allocator.
*/
static struct folio *alloc_surplus_hugetlb_folio(struct hstate *h,
gfp_t gfp_mask, int nid, nodemask_t *nmask)
{
struct folio *folio = NULL;
if (hstate_is_gigantic(h))
return NULL;
spin_lock_irq(&hugetlb_lock);
if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages)
goto out_unlock;
spin_unlock_irq(&hugetlb_lock);
folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL);
if (!folio)
return NULL;
spin_lock_irq(&hugetlb_lock);
/*
* We could have raced with the pool size change.
* Double check that and simply deallocate the new page
* if we would end up overcommiting the surpluses. Abuse
* temporary page to workaround the nasty free_huge_folio
* codeflow
*/
if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) {
folio_set_hugetlb_temporary(folio);
spin_unlock_irq(&hugetlb_lock);
free_huge_folio(folio);
return NULL;
}
h->surplus_huge_pages++;
h->surplus_huge_pages_node[folio_nid(folio)]++;
out_unlock:
spin_unlock_irq(&hugetlb_lock);
return folio;
}
static struct folio *alloc_migrate_hugetlb_folio(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nmask)
{
struct folio *folio;
if (hstate_is_gigantic(h))
return NULL;
folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid, nmask, NULL);
if (!folio)
return NULL;
/* fresh huge pages are frozen */
folio_ref_unfreeze(folio, 1);
/*
* We do not account these pages as surplus because they are only
* temporary and will be released properly on the last reference
*/
folio_set_hugetlb_temporary(folio);
return folio;
}
/*
* Use the VMA's mpolicy to allocate a huge page from the buddy.
*/
static
struct folio *alloc_buddy_hugetlb_folio_with_mpol(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
struct folio *folio = NULL;
struct mempolicy *mpol;
gfp_t gfp_mask = htlb_alloc_mask(h);
int nid;
nodemask_t *nodemask;
nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask);
if (mpol_is_preferred_many(mpol)) {
gfp_t gfp = gfp_mask | __GFP_NOWARN;
gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL);
folio = alloc_surplus_hugetlb_folio(h, gfp, nid, nodemask);
/* Fallback to all nodes if page==NULL */
nodemask = NULL;
}
if (!folio)
folio = alloc_surplus_hugetlb_folio(h, gfp_mask, nid, nodemask);
mpol_cond_put(mpol);
return folio;
}
/* folio migration callback function */
struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
nodemask_t *nmask, gfp_t gfp_mask)
{
spin_lock_irq(&hugetlb_lock);
if (available_huge_pages(h)) {
struct folio *folio;
folio = dequeue_hugetlb_folio_nodemask(h, gfp_mask,
preferred_nid, nmask);
if (folio) {
spin_unlock_irq(&hugetlb_lock);
return folio;
}
}
spin_unlock_irq(&hugetlb_lock);
return alloc_migrate_hugetlb_folio(h, gfp_mask, preferred_nid, nmask);
}
/*
* Increase the hugetlb pool such that it can accommodate a reservation
* of size 'delta'.
*/
static int gather_surplus_pages(struct hstate *h, long delta)
__must_hold(&hugetlb_lock)
{
LIST_HEAD(surplus_list);
struct folio *folio, *tmp;
int ret;
long i;
long needed, allocated;
bool alloc_ok = true;
lockdep_assert_held(&hugetlb_lock);
needed = (h->resv_huge_pages + delta) - h->free_huge_pages;
if (needed <= 0) {
h->resv_huge_pages += delta;
return 0;
}
allocated = 0;
ret = -ENOMEM;
retry:
spin_unlock_irq(&hugetlb_lock);
for (i = 0; i < needed; i++) {
folio = alloc_surplus_hugetlb_folio(h, htlb_alloc_mask(h),
NUMA_NO_NODE, NULL);
if (!folio) {
alloc_ok = false;
break;
}
list_add(&folio->lru, &surplus_list);
cond_resched();
}
allocated += i;
/*
* After retaking hugetlb_lock, we need to recalculate 'needed'
* because either resv_huge_pages or free_huge_pages may have changed.
*/
spin_lock_irq(&hugetlb_lock);
needed = (h->resv_huge_pages + delta) -
(h->free_huge_pages + allocated);
if (needed > 0) {
if (alloc_ok)
goto retry;
/*
* We were not able to allocate enough pages to
* satisfy the entire reservation so we free what
* we've allocated so far.
*/
goto free;
}
/*
* The surplus_list now contains _at_least_ the number of extra pages
* needed to accommodate the reservation. Add the appropriate number
* of pages to the hugetlb pool and free the extras back to the buddy
* allocator. Commit the entire reservation here to prevent another
* process from stealing the pages as they are added to the pool but
* before they are reserved.
*/
needed += allocated;
h->resv_huge_pages += delta;
ret = 0;
/* Free the needed pages to the hugetlb pool */
list_for_each_entry_safe(folio, tmp, &surplus_list, lru) {
if ((--needed) < 0)
break;
/* Add the page to the hugetlb allocator */
enqueue_hugetlb_folio(h, folio);
}
free:
spin_unlock_irq(&hugetlb_lock);
/*
* Free unnecessary surplus pages to the buddy allocator.
* Pages have no ref count, call free_huge_folio directly.
*/
list_for_each_entry_safe(folio, tmp, &surplus_list, lru)
free_huge_folio(folio);
spin_lock_irq(&hugetlb_lock);
return ret;
}
/*
* This routine has two main purposes:
* 1) Decrement the reservation count (resv_huge_pages) by the value passed
* in unused_resv_pages. This corresponds to the prior adjustments made
* to the associated reservation map.
* 2) Free any unused surplus pages that may have been allocated to satisfy
* the reservation. As many as unused_resv_pages may be freed.
*/
static void return_unused_surplus_pages(struct hstate *h,
unsigned long unused_resv_pages)
{
unsigned long nr_pages;
LIST_HEAD(page_list);
lockdep_assert_held(&hugetlb_lock);
/* Uncommit the reservation */
h->resv_huge_pages -= unused_resv_pages;
if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
goto out;
/*
* Part (or even all) of the reservation could have been backed
* by pre-allocated pages. Only free surplus pages.
*/
nr_pages = min(unused_resv_pages, h->surplus_huge_pages);
/*
* We want to release as many surplus pages as possible, spread
* evenly across all nodes with memory. Iterate across these nodes
* until we can no longer free unreserved surplus pages. This occurs
* when the nodes with surplus pages have no free pages.
* remove_pool_hugetlb_folio() will balance the freed pages across the
* on-line nodes with memory and will handle the hstate accounting.
*/
while (nr_pages--) {
struct folio *folio;
folio = remove_pool_hugetlb_folio(h, &node_states[N_MEMORY], 1);
if (!folio)
goto out;
list_add(&folio->lru, &page_list);
}
out:
spin_unlock_irq(&hugetlb_lock);
update_and_free_pages_bulk(h, &page_list);
spin_lock_irq(&hugetlb_lock);
}
/*
* vma_needs_reservation, vma_commit_reservation and vma_end_reservation
* are used by the huge page allocation routines to manage reservations.
*
* vma_needs_reservation is called to determine if the huge page at addr
* within the vma has an associated reservation. If a reservation is
* needed, the value 1 is returned. The caller is then responsible for
* managing the global reservation and subpool usage counts. After
* the huge page has been allocated, vma_commit_reservation is called
* to add the page to the reservation map. If the page allocation fails,
* the reservation must be ended instead of committed. vma_end_reservation
* is called in such cases.
*
* In the normal case, vma_commit_reservation returns the same value
* as the preceding vma_needs_reservation call. The only time this
* is not the case is if a reserve map was changed between calls. It
* is the responsibility of the caller to notice the difference and
* take appropriate action.
*
* vma_add_reservation is used in error paths where a reservation must
* be restored when a newly allocated huge page must be freed. It is
* to be called after calling vma_needs_reservation to determine if a
* reservation exists.
*
* vma_del_reservation is used in error paths where an entry in the reserve
* map was created during huge page allocation and must be removed. It is to
* be called after calling vma_needs_reservation to determine if a reservation
* exists.
*/
enum vma_resv_mode {
VMA_NEEDS_RESV,
VMA_COMMIT_RESV,
VMA_END_RESV,
VMA_ADD_RESV,
VMA_DEL_RESV,
};
static long __vma_reservation_common(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr,
enum vma_resv_mode mode)
{
struct resv_map *resv;
pgoff_t idx;
long ret;
long dummy_out_regions_needed;
resv = vma_resv_map(vma);
if (!resv)
return 1;
idx = vma_hugecache_offset(h, vma, addr);
switch (mode) {
case VMA_NEEDS_RESV:
ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed);
/* We assume that vma_reservation_* routines always operate on
* 1 page, and that adding to resv map a 1 page entry can only
* ever require 1 region.
*/
VM_BUG_ON(dummy_out_regions_needed != 1);
break;
case VMA_COMMIT_RESV:
ret = region_add(resv, idx, idx + 1, 1, NULL, NULL);
/* region_add calls of range 1 should never fail. */
VM_BUG_ON(ret < 0);
break;
case VMA_END_RESV:
region_abort(resv, idx, idx + 1, 1);
ret = 0;
break;
case VMA_ADD_RESV:
if (vma->vm_flags & VM_MAYSHARE) {
ret = region_add(resv, idx, idx + 1, 1, NULL, NULL);
/* region_add calls of range 1 should never fail. */
VM_BUG_ON(ret < 0);
} else {
region_abort(resv, idx, idx + 1, 1);
ret = region_del(resv, idx, idx + 1);
}
break;
case VMA_DEL_RESV:
if (vma->vm_flags & VM_MAYSHARE) {
region_abort(resv, idx, idx + 1, 1);
ret = region_del(resv, idx, idx + 1);
} else {
ret = region_add(resv, idx, idx + 1, 1, NULL, NULL);
/* region_add calls of range 1 should never fail. */
VM_BUG_ON(ret < 0);
}
break;
default:
BUG();
}
if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV)
return ret;
/*
* We know private mapping must have HPAGE_RESV_OWNER set.
*
* In most cases, reserves always exist for private mappings.
* However, a file associated with mapping could have been
* hole punched or truncated after reserves were consumed.
* As subsequent fault on such a range will not use reserves.
* Subtle - The reserve map for private mappings has the
* opposite meaning than that of shared mappings. If NO
* entry is in the reserve map, it means a reservation exists.
* If an entry exists in the reserve map, it means the
* reservation has already been consumed. As a result, the
* return value of this routine is the opposite of the
* value returned from reserve map manipulation routines above.
*/
if (ret > 0)
return 0;
if (ret == 0)
return 1;
return ret;
}
static long vma_needs_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV);
}
static long vma_commit_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV);
}
static void vma_end_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
(void)__vma_reservation_common(h, vma, addr, VMA_END_RESV);
}
static long vma_add_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV);
}
static long vma_del_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV);
}
/*
* This routine is called to restore reservation information on error paths.
* It should ONLY be called for folios allocated via alloc_hugetlb_folio(),
* and the hugetlb mutex should remain held when calling this routine.
*
* It handles two specific cases:
* 1) A reservation was in place and the folio consumed the reservation.
* hugetlb_restore_reserve is set in the folio.
* 2) No reservation was in place for the page, so hugetlb_restore_reserve is
* not set. However, alloc_hugetlb_folio always updates the reserve map.
*
* In case 1, free_huge_folio later in the error path will increment the
* global reserve count. But, free_huge_folio does not have enough context
* to adjust the reservation map. This case deals primarily with private
* mappings. Adjust the reserve map here to be consistent with global
* reserve count adjustments to be made by free_huge_folio. Make sure the
* reserve map indicates there is a reservation present.
*
* In case 2, simply undo reserve map modifications done by alloc_hugetlb_folio.
*/
void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma,
unsigned long address, struct folio *folio)
{
long rc = vma_needs_reservation(h, vma, address);
if (folio_test_hugetlb_restore_reserve(folio)) {
if (unlikely(rc < 0))
/*
* Rare out of memory condition in reserve map
* manipulation. Clear hugetlb_restore_reserve so
* that global reserve count will not be incremented
* by free_huge_folio. This will make it appear
* as though the reservation for this folio was
* consumed. This may prevent the task from
* faulting in the folio at a later time. This
* is better than inconsistent global huge page
* accounting of reserve counts.
*/
folio_clear_hugetlb_restore_reserve(folio);
else if (rc)
(void)vma_add_reservation(h, vma, address);
else
vma_end_reservation(h, vma, address);
} else {
if (!rc) {
/*
* This indicates there is an entry in the reserve map
* not added by alloc_hugetlb_folio. We know it was added
* before the alloc_hugetlb_folio call, otherwise
* hugetlb_restore_reserve would be set on the folio.
* Remove the entry so that a subsequent allocation
* does not consume a reservation.
*/
rc = vma_del_reservation(h, vma, address);
if (rc < 0)
/*
* VERY rare out of memory condition. Since
* we can not delete the entry, set
* hugetlb_restore_reserve so that the reserve
* count will be incremented when the folio
* is freed. This reserve will be consumed
* on a subsequent allocation.
*/
folio_set_hugetlb_restore_reserve(folio);
} else if (rc < 0) {
/*
* Rare out of memory condition from
* vma_needs_reservation call. Memory allocation is
* only attempted if a new entry is needed. Therefore,
* this implies there is not an entry in the
* reserve map.
*
* For shared mappings, no entry in the map indicates
* no reservation. We are done.
*/
if (!(vma->vm_flags & VM_MAYSHARE))
/*
* For private mappings, no entry indicates
* a reservation is present. Since we can
* not add an entry, set hugetlb_restore_reserve
* on the folio so reserve count will be
* incremented when freed. This reserve will
* be consumed on a subsequent allocation.
*/
folio_set_hugetlb_restore_reserve(folio);
} else
/*
* No reservation present, do nothing
*/
vma_end_reservation(h, vma, address);
}
}
/*
* alloc_and_dissolve_hugetlb_folio - Allocate a new folio and dissolve
* the old one
* @h: struct hstate old page belongs to
* @old_folio: Old folio to dissolve
* @list: List to isolate the page in case we need to
* Returns 0 on success, otherwise negated error.
*/
static int alloc_and_dissolve_hugetlb_folio(struct hstate *h,
struct folio *old_folio, struct list_head *list)
{
gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
int nid = folio_nid(old_folio);
struct folio *new_folio = NULL;
int ret = 0;
retry:
spin_lock_irq(&hugetlb_lock);
if (!folio_test_hugetlb(old_folio)) {
/*
* Freed from under us. Drop new_folio too.
*/
goto free_new;
} else if (folio_ref_count(old_folio)) {
bool isolated;
/*
* Someone has grabbed the folio, try to isolate it here.
* Fail with -EBUSY if not possible.
*/
spin_unlock_irq(&hugetlb_lock);
isolated = isolate_hugetlb(old_folio, list);
ret = isolated ? 0 : -EBUSY;
spin_lock_irq(&hugetlb_lock);
goto free_new;
} else if (!folio_test_hugetlb_freed(old_folio)) {
/*
* Folio's refcount is 0 but it has not been enqueued in the
* freelist yet. Race window is small, so we can succeed here if
* we retry.
*/
spin_unlock_irq(&hugetlb_lock);
cond_resched();
goto retry;
} else {
if (!new_folio) {
spin_unlock_irq(&hugetlb_lock);
new_folio = alloc_buddy_hugetlb_folio(h, gfp_mask, nid,
NULL, NULL);
if (!new_folio)
return -ENOMEM;
__prep_new_hugetlb_folio(h, new_folio);
goto retry;
}
/*
* Ok, old_folio is still a genuine free hugepage. Remove it from
* the freelist and decrease the counters. These will be
* incremented again when calling __prep_account_new_huge_page()
* and enqueue_hugetlb_folio() for new_folio. The counters will
* remain stable since this happens under the lock.
*/
remove_hugetlb_folio(h, old_folio, false);
/*
* Ref count on new_folio is already zero as it was dropped
* earlier. It can be directly added to the pool free list.
*/
__prep_account_new_huge_page(h, nid);
enqueue_hugetlb_folio(h, new_folio);
/*
* Folio has been replaced, we can safely free the old one.
*/
spin_unlock_irq(&hugetlb_lock);
update_and_free_hugetlb_folio(h, old_folio, false);
}
return ret;
free_new:
spin_unlock_irq(&hugetlb_lock);
if (new_folio) {
/* Folio has a zero ref count, but needs a ref to be freed */
folio_ref_unfreeze(new_folio, 1);
update_and_free_hugetlb_folio(h, new_folio, false);
}
return ret;
}
int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list)
{
struct hstate *h;
struct folio *folio = page_folio(page);
int ret = -EBUSY;
/*
* The page might have been dissolved from under our feet, so make sure
* to carefully check the state under the lock.
* Return success when racing as if we dissolved the page ourselves.
*/
spin_lock_irq(&hugetlb_lock);
if (folio_test_hugetlb(folio)) {
h = folio_hstate(folio);
} else {
spin_unlock_irq(&hugetlb_lock);
return 0;
}
spin_unlock_irq(&hugetlb_lock);
/*
* Fence off gigantic pages as there is a cyclic dependency between
* alloc_contig_range and them. Return -ENOMEM as this has the effect
* of bailing out right away without further retrying.
*/
if (hstate_is_gigantic(h))
return -ENOMEM;
if (folio_ref_count(folio) && isolate_hugetlb(folio, list))
ret = 0;
else if (!folio_ref_count(folio))
ret = alloc_and_dissolve_hugetlb_folio(h, folio, list);
return ret;
}
struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
unsigned long addr, int avoid_reserve)
{
struct hugepage_subpool *spool = subpool_vma(vma);
struct hstate *h = hstate_vma(vma);
struct folio *folio;
long map_chg, map_commit, nr_pages = pages_per_huge_page(h);
long gbl_chg;
int memcg_charge_ret, ret, idx;
struct hugetlb_cgroup *h_cg = NULL;
struct mem_cgroup *memcg;
bool deferred_reserve;
gfp_t gfp = htlb_alloc_mask(h) | __GFP_RETRY_MAYFAIL;
memcg = get_mem_cgroup_from_current();
memcg_charge_ret = mem_cgroup_hugetlb_try_charge(memcg, gfp, nr_pages);
if (memcg_charge_ret == -ENOMEM) {
mem_cgroup_put(memcg);
return ERR_PTR(-ENOMEM);
}
idx = hstate_index(h);
/*
* Examine the region/reserve map to determine if the process
* has a reservation for the page to be allocated. A return
* code of zero indicates a reservation exists (no change).
*/
map_chg = gbl_chg = vma_needs_reservation(h, vma, addr);
if (map_chg < 0) {
if (!memcg_charge_ret)
mem_cgroup_cancel_charge(memcg, nr_pages);
mem_cgroup_put(memcg);
return ERR_PTR(-ENOMEM);
}
/*
* Processes that did not create the mapping will have no
* reserves as indicated by the region/reserve map. Check
* that the allocation will not exceed the subpool limit.
* Allocations for MAP_NORESERVE mappings also need to be
* checked against any subpool limit.
*/
if (map_chg || avoid_reserve) {
gbl_chg = hugepage_subpool_get_pages(spool, 1);
if (gbl_chg < 0)
goto out_end_reservation;
/*
* Even though there was no reservation in the region/reserve
* map, there could be reservations associated with the
* subpool that can be used. This would be indicated if the
* return value of hugepage_subpool_get_pages() is zero.
* However, if avoid_reserve is specified we still avoid even
* the subpool reservations.
*/
if (avoid_reserve)
gbl_chg = 1;
}
/* If this allocation is not consuming a reservation, charge it now.
*/
deferred_reserve = map_chg || avoid_reserve;
if (deferred_reserve) {
ret = hugetlb_cgroup_charge_cgroup_rsvd(
idx, pages_per_huge_page(h), &h_cg);
if (ret)
goto out_subpool_put;
}
ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg);
if (ret)
goto out_uncharge_cgroup_reservation;
spin_lock_irq(&hugetlb_lock);
/*
* glb_chg is passed to indicate whether or not a page must be taken
* from the global free pool (global change). gbl_chg == 0 indicates
* a reservation exists for the allocation.
*/
folio = dequeue_hugetlb_folio_vma(h, vma, addr, avoid_reserve, gbl_chg);
if (!folio) {
spin_unlock_irq(&hugetlb_lock);
folio = alloc_buddy_hugetlb_folio_with_mpol(h, vma, addr);
if (!folio)
goto out_uncharge_cgroup;
spin_lock_irq(&hugetlb_lock);
if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) {
folio_set_hugetlb_restore_reserve(folio);
h->resv_huge_pages--;
}
list_add(&folio->lru, &h->hugepage_activelist);
folio_ref_unfreeze(folio, 1);
/* Fall through */
}
hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, folio);
/* If allocation is not consuming a reservation, also store the
* hugetlb_cgroup pointer on the page.
*/
if (deferred_reserve) {
hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h),
h_cg, folio);
}
spin_unlock_irq(&hugetlb_lock);
hugetlb_set_folio_subpool(folio, spool);
map_commit = vma_commit_reservation(h, vma, addr);
if (unlikely(map_chg > map_commit)) {
/*
* The page was added to the reservation map between
* vma_needs_reservation and vma_commit_reservation.
* This indicates a race with hugetlb_reserve_pages.
* Adjust for the subpool count incremented above AND
* in hugetlb_reserve_pages for the same page. Also,
* the reservation count added in hugetlb_reserve_pages
* no longer applies.
*/
long rsv_adjust;
rsv_adjust = hugepage_subpool_put_pages(spool, 1);
hugetlb_acct_memory(h, -rsv_adjust);
if (deferred_reserve)
hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h),
pages_per_huge_page(h), folio);
}
if (!memcg_charge_ret)
mem_cgroup_commit_charge(folio, memcg);
mem_cgroup_put(memcg);
return folio;
out_uncharge_cgroup:
hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg);
out_uncharge_cgroup_reservation:
if (deferred_reserve)
hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h),
h_cg);
out_subpool_put:
if (map_chg || avoid_reserve)
hugepage_subpool_put_pages(spool, 1);
out_end_reservation:
vma_end_reservation(h, vma, addr);
if (!memcg_charge_ret)
mem_cgroup_cancel_charge(memcg, nr_pages);
mem_cgroup_put(memcg);
return ERR_PTR(-ENOSPC);
}
int alloc_bootmem_huge_page(struct hstate *h, int nid)
__attribute__ ((weak, alias("__alloc_bootmem_huge_page")));
int __alloc_bootmem_huge_page(struct hstate *h, int nid)
{
struct huge_bootmem_page *m = NULL; /* initialize for clang */
int nr_nodes, node = nid;
/* do node specific alloc */
if (nid != NUMA_NO_NODE) {
m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h),
0, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
if (!m)
return 0;
goto found;
}
/* allocate from next node when distributing huge pages */
for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, &node_states[N_MEMORY]) {
m = memblock_alloc_try_nid_raw(
huge_page_size(h), huge_page_size(h),
0, MEMBLOCK_ALLOC_ACCESSIBLE, node);
/*
* Use the beginning of the huge page to store the
* huge_bootmem_page struct (until gather_bootmem
* puts them into the mem_map).
*/
if (!m)
return 0;
goto found;
}
found:
/*
* Only initialize the head struct page in memmap_init_reserved_pages,
* rest of the struct pages will be initialized by the HugeTLB
* subsystem itself.
* The head struct page is used to get folio information by the HugeTLB
* subsystem like zone id and node id.
*/
memblock_reserved_mark_noinit(virt_to_phys((void *)m + PAGE_SIZE),
huge_page_size(h) - PAGE_SIZE);
/* Put them into a private list first because mem_map is not up yet */
INIT_LIST_HEAD(&m->list);
list_add(&m->list, &huge_boot_pages[node]);
m->hstate = h;
return 1;
}
/* Initialize [start_page:end_page_number] tail struct pages of a hugepage */
static void __init hugetlb_folio_init_tail_vmemmap(struct folio *folio,
unsigned long start_page_number,
unsigned long end_page_number)
{
enum zone_type zone = zone_idx(folio_zone(folio));
int nid = folio_nid(folio);
unsigned long head_pfn = folio_pfn(folio);
unsigned long pfn, end_pfn = head_pfn + end_page_number;
int ret;
for (pfn = head_pfn + start_page_number; pfn < end_pfn; pfn++) {
struct page *page = pfn_to_page(pfn);
__init_single_page(page, pfn, zone, nid);
prep_compound_tail((struct page *)folio, pfn - head_pfn);
ret = page_ref_freeze(page, 1);
VM_BUG_ON(!ret);
}
}
static void __init hugetlb_folio_init_vmemmap(struct folio *folio,
struct hstate *h,
unsigned long nr_pages)
{
int ret;
/* Prepare folio head */
__folio_clear_reserved(folio);
__folio_set_head(folio);
ret = folio_ref_freeze(folio, 1);
VM_BUG_ON(!ret);
/* Initialize the necessary tail struct pages */
hugetlb_folio_init_tail_vmemmap(folio, 1, nr_pages);
prep_compound_head((struct page *)folio, huge_page_order(h));
}
static void __init prep_and_add_bootmem_folios(struct hstate *h,
struct list_head *folio_list)
{
unsigned long flags;
struct folio *folio, *tmp_f;
/* Send list for bulk vmemmap optimization processing */
hugetlb_vmemmap_optimize_folios(h, folio_list);
list_for_each_entry_safe(folio, tmp_f, folio_list, lru) {
if (!folio_test_hugetlb_vmemmap_optimized(folio)) {
/*
* If HVO fails, initialize all tail struct pages
* We do not worry about potential long lock hold
* time as this is early in boot and there should
* be no contention.
*/
hugetlb_folio_init_tail_vmemmap(folio,
HUGETLB_VMEMMAP_RESERVE_PAGES,
pages_per_huge_page(h));
}
/* Subdivide locks to achieve better parallel performance */
spin_lock_irqsave(&hugetlb_lock, flags);
__prep_account_new_huge_page(h, folio_nid(folio));
enqueue_hugetlb_folio(h, folio);
spin_unlock_irqrestore(&hugetlb_lock, flags);
}
}
/*
* Put bootmem huge pages into the standard lists after mem_map is up.
* Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages.
*/
static void __init gather_bootmem_prealloc_node(unsigned long nid)
{
LIST_HEAD(folio_list);
struct huge_bootmem_page *m;
struct hstate *h = NULL, *prev_h = NULL;
list_for_each_entry(m, &huge_boot_pages[nid], list) {
struct page *page = virt_to_page(m);
struct folio *folio = (void *)page;
h = m->hstate;
/*
* It is possible to have multiple huge page sizes (hstates)
* in this list. If so, process each size separately.
*/
if (h != prev_h && prev_h != NULL)
prep_and_add_bootmem_folios(prev_h, &folio_list);
prev_h = h;
VM_BUG_ON(!hstate_is_gigantic(h));
WARN_ON(folio_ref_count(folio) != 1);
hugetlb_folio_init_vmemmap(folio, h,
HUGETLB_VMEMMAP_RESERVE_PAGES);
init_new_hugetlb_folio(h, folio);
list_add(&folio->lru, &folio_list);
/*
* We need to restore the 'stolen' pages to totalram_pages
* in order to fix confusing memory reports from free(1) and
* other side-effects, like CommitLimit going negative.
*/
adjust_managed_page_count(page, pages_per_huge_page(h));
cond_resched();
}
prep_and_add_bootmem_folios(h, &folio_list);
}
static void __init gather_bootmem_prealloc_parallel(unsigned long start,
unsigned long end, void *arg)
{
int nid;
for (nid = start; nid < end; nid++)
gather_bootmem_prealloc_node(nid);
}
static void __init gather_bootmem_prealloc(void)
{
struct padata_mt_job job = {
.thread_fn = gather_bootmem_prealloc_parallel,
.fn_arg = NULL,
.start = 0,
.size = num_node_state(N_MEMORY),
.align = 1,
.min_chunk = 1,
.max_threads = num_node_state(N_MEMORY),
.numa_aware = true,
};
padata_do_multithreaded(&job);
}
static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid)
{
unsigned long i;
char buf[32];
for (i = 0; i < h->max_huge_pages_node[nid]; ++i) {
if (hstate_is_gigantic(h)) {
if (!alloc_bootmem_huge_page(h, nid))
break;
} else {
struct folio *folio;
gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
folio = alloc_fresh_hugetlb_folio(h, gfp_mask, nid,
&node_states[N_MEMORY], NULL);
if (!folio)
break;
free_huge_folio(folio); /* free it into the hugepage allocator */
}
cond_resched();
}
if (i == h->max_huge_pages_node[nid])
return;
string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
pr_warn("HugeTLB: allocating %u of page size %s failed node%d. Only allocated %lu hugepages.\n",
h->max_huge_pages_node[nid], buf, nid, i);
h->max_huge_pages -= (h->max_huge_pages_node[nid] - i);
h->max_huge_pages_node[nid] = i;
}
static bool __init hugetlb_hstate_alloc_pages_specific_nodes(struct hstate *h)
{
int i;
bool node_specific_alloc = false;
for_each_online_node(i) {
if (h->max_huge_pages_node[i] > 0) {
hugetlb_hstate_alloc_pages_onenode(h, i);
node_specific_alloc = true;
}
}
return node_specific_alloc;
}
static void __init hugetlb_hstate_alloc_pages_errcheck(unsigned long allocated, struct hstate *h)
{
if (allocated < h->max_huge_pages) {
char buf[32];
string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n",
h->max_huge_pages, buf, allocated);
h->max_huge_pages = allocated;
}
}
static void __init hugetlb_pages_alloc_boot_node(unsigned long start, unsigned long end, void *arg)
{
struct hstate *h = (struct hstate *)arg;
int i, num = end - start;
nodemask_t node_alloc_noretry;
LIST_HEAD(folio_list);
int next_node = first_online_node;
/* Bit mask controlling how hard we retry per-node allocations.*/
nodes_clear(node_alloc_noretry);
for (i = 0; i < num; ++i) {
struct folio *folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY],
&node_alloc_noretry, &next_node);
if (!folio)
break;
list_move(&folio->lru, &folio_list);
cond_resched();
}
prep_and_add_allocated_folios(h, &folio_list);
}
static unsigned long __init hugetlb_gigantic_pages_alloc_boot(struct hstate *h)
{
unsigned long i;
for (i = 0; i < h->max_huge_pages; ++i) {
if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE))
break;
cond_resched();
}
return i;
}
static unsigned long __init hugetlb_pages_alloc_boot(struct hstate *h)
{
struct padata_mt_job job = {
.fn_arg = h,
.align = 1,
.numa_aware = true
};
job.thread_fn = hugetlb_pages_alloc_boot_node;
job.start = 0;
job.size = h->max_huge_pages;
/*
* job.max_threads is twice the num_node_state(N_MEMORY),
*
* Tests below indicate that a multiplier of 2 significantly improves
* performance, and although larger values also provide improvements,
* the gains are marginal.
*
* Therefore, choosing 2 as the multiplier strikes a good balance between
* enhancing parallel processing capabilities and maintaining efficient
* resource management.
*
* +------------+-------+-------+-------+-------+-------+
* | multiplier | 1 | 2 | 3 | 4 | 5 |
* +------------+-------+-------+-------+-------+-------+
* | 256G 2node | 358ms | 215ms | 157ms | 134ms | 126ms |
* | 2T 4node | 979ms | 679ms | 543ms | 489ms | 481ms |
* | 50G 2node | 71ms | 44ms | 37ms | 30ms | 31ms |
* +------------+-------+-------+-------+-------+-------+
*/
job.max_threads = num_node_state(N_MEMORY) * 2;
job.min_chunk = h->max_huge_pages / num_node_state(N_MEMORY) / 2;
padata_do_multithreaded(&job);
return h->nr_huge_pages;
}
/*
* NOTE: this routine is called in different contexts for gigantic and
* non-gigantic pages.
* - For gigantic pages, this is called early in the boot process and
* pages are allocated from memblock allocated or something similar.
* Gigantic pages are actually added to pools later with the routine
* gather_bootmem_prealloc.
* - For non-gigantic pages, this is called later in the boot process after
* all of mm is up and functional. Pages are allocated from buddy and
* then added to hugetlb pools.
*/
static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
{
unsigned long allocated;
static bool initialized __initdata;
/* skip gigantic hugepages allocation if hugetlb_cma enabled */
if (hstate_is_gigantic(h) && hugetlb_cma_size) {
pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n");
return;
}
/* hugetlb_hstate_alloc_pages will be called many times, initialize huge_boot_pages once */
if (!initialized) {
int i = 0;
for (i = 0; i < MAX_NUMNODES; i++)
INIT_LIST_HEAD(&huge_boot_pages[i]);
initialized = true;
}
/* do node specific alloc */
if (hugetlb_hstate_alloc_pages_specific_nodes(h))
return;
/* below will do all node balanced alloc */
if (hstate_is_gigantic(h))
allocated = hugetlb_gigantic_pages_alloc_boot(h);
else
allocated = hugetlb_pages_alloc_boot(h);
hugetlb_hstate_alloc_pages_errcheck(allocated, h);
}
static void __init hugetlb_init_hstates(void)
{
struct hstate *h, *h2;
for_each_hstate(h) {
/* oversize hugepages were init'ed in early boot */
if (!hstate_is_gigantic(h))
hugetlb_hstate_alloc_pages(h);
/*
* Set demote order for each hstate. Note that
* h->demote_order is initially 0.
* - We can not demote gigantic pages if runtime freeing
* is not supported, so skip this.
* - If CMA allocation is possible, we can not demote
* HUGETLB_PAGE_ORDER or smaller size pages.
*/
if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
continue;
if (hugetlb_cma_size && h->order <= HUGETLB_PAGE_ORDER)
continue;
for_each_hstate(h2) {
if (h2 == h)
continue;
if (h2->order < h->order &&
h2->order > h->demote_order)
h->demote_order = h2->order;
}
}
}
static void __init report_hugepages(void)
{
struct hstate *h;
for_each_hstate(h) {
char buf[32];
string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
pr_info("HugeTLB: registered %s page size, pre-allocated %ld pages\n",
buf, h->free_huge_pages);
pr_info("HugeTLB: %d KiB vmemmap can be freed for a %s page\n",
hugetlb_vmemmap_optimizable_size(h) / SZ_1K, buf);
}
}
#ifdef CONFIG_HIGHMEM
static void try_to_free_low(struct hstate *h, unsigned long count,
nodemask_t *nodes_allowed)
{
int i;
LIST_HEAD(page_list);
lockdep_assert_held(&hugetlb_lock);
if (hstate_is_gigantic(h))
return;
/*
* Collect pages to be freed on a list, and free after dropping lock
*/
for_each_node_mask(i, *nodes_allowed) {
struct folio *folio, *next;
struct list_head *freel = &h->hugepage_freelists[i];
list_for_each_entry_safe(folio, next, freel, lru) {
if (count >= h->nr_huge_pages)
goto out;
if (folio_test_highmem(folio))
continue;
remove_hugetlb_folio(h, folio, false);
list_add(&folio->lru, &page_list);
}
}
out:
spin_unlock_irq(&hugetlb_lock);
update_and_free_pages_bulk(h, &page_list);
spin_lock_irq(&hugetlb_lock);
}
#else
static inline void try_to_free_low(struct hstate *h, unsigned long count,
nodemask_t *nodes_allowed)
{
}
#endif
/*
* Increment or decrement surplus_huge_pages. Keep node-specific counters
* balanced by operating on them in a round-robin fashion.
* Returns 1 if an adjustment was made.
*/
static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
int delta)
{
int nr_nodes, node;
lockdep_assert_held(&hugetlb_lock);
VM_BUG_ON(delta != -1 && delta != 1);
if (delta < 0) {
for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, nodes_allowed) {
if (h->surplus_huge_pages_node[node])
goto found;
}
} else {
for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) {
if (h->surplus_huge_pages_node[node] <
h->nr_huge_pages_node[node])
goto found;
}
}
return 0;
found:
h->surplus_huge_pages += delta;
h->surplus_huge_pages_node[node] += delta;
return 1;
}
#define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
nodemask_t *nodes_allowed)
{
unsigned long min_count;
unsigned long allocated;
struct folio *folio;
LIST_HEAD(page_list);
NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL);
/*
* Bit mask controlling how hard we retry per-node allocations.
* If we can not allocate the bit mask, do not attempt to allocate
* the requested huge pages.
*/
if (node_alloc_noretry)
nodes_clear(*node_alloc_noretry);
else
return -ENOMEM;
/*
* resize_lock mutex prevents concurrent adjustments to number of
* pages in hstate via the proc/sysfs interfaces.
*/
mutex_lock(&h->resize_lock);
flush_free_hpage_work(h);
spin_lock_irq(&hugetlb_lock);
/*
* Check for a node specific request.
* Changing node specific huge page count may require a corresponding
* change to the global count. In any case, the passed node mask
* (nodes_allowed) will restrict alloc/free to the specified node.
*/
if (nid != NUMA_NO_NODE) {
unsigned long old_count = count;
count += persistent_huge_pages(h) -
(h->nr_huge_pages_node[nid] -
h->surplus_huge_pages_node[nid]);
/*
* User may have specified a large count value which caused the
* above calculation to overflow. In this case, they wanted
* to allocate as many huge pages as possible. Set count to
* largest possible value to align with their intention.
*/
if (count < old_count)
count = ULONG_MAX;
}
/*
* Gigantic pages runtime allocation depend on the capability for large
* page range allocation.
* If the system does not provide this feature, return an error when
* the user tries to allocate gigantic pages but let the user free the
* boottime allocated gigantic pages.
*/
if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) {
if (count > persistent_huge_pages(h)) {
spin_unlock_irq(&hugetlb_lock);
mutex_unlock(&h->resize_lock);
NODEMASK_FREE(node_alloc_noretry);
return -EINVAL;
}
/* Fall through to decrease pool */
}
/*
* Increase the pool size
* First take pages out of surplus state. Then make up the
* remaining difference by allocating fresh huge pages.
*
* We might race with alloc_surplus_hugetlb_folio() here and be unable
* to convert a surplus huge page to a normal huge page. That is
* not critical, though, it just means the overall size of the
* pool might be one hugepage larger than it needs to be, but
* within all the constraints specified by the sysctls.
*/
while (h->surplus_huge_pages && count > persistent_huge_pages(h)) {
if (!adjust_pool_surplus(h, nodes_allowed, -1))
break;
}
allocated = 0;
while (count > (persistent_huge_pages(h) + allocated)) {
/*
* If this allocation races such that we no longer need the
* page, free_huge_folio will handle it by freeing the page
* and reducing the surplus.
*/
spin_unlock_irq(&hugetlb_lock);
/* yield cpu to avoid soft lockup */
cond_resched();
folio = alloc_pool_huge_folio(h, nodes_allowed,
node_alloc_noretry,
&h->next_nid_to_alloc);
if (!folio) {
prep_and_add_allocated_folios(h, &page_list);
spin_lock_irq(&hugetlb_lock);
goto out;
}
list_add(&folio->lru, &page_list);
allocated++;
/* Bail for signals. Probably ctrl-c from user */
if (signal_pending(current)) {
prep_and_add_allocated_folios(h, &page_list);
spin_lock_irq(&hugetlb_lock);
goto out;
}
spin_lock_irq(&hugetlb_lock);
}
/* Add allocated pages to the pool */
if (!list_empty(&page_list)) {
spin_unlock_irq(&hugetlb_lock);
prep_and_add_allocated_folios(h, &page_list);
spin_lock_irq(&hugetlb_lock);
}
/*
* Decrease the pool size
* First return free pages to the buddy allocator (being careful
* to keep enough around to satisfy reservations). Then place
* pages into surplus state as needed so the pool will shrink
* to the desired size as pages become free.
*
* By placing pages into the surplus state independent of the
* overcommit value, we are allowing the surplus pool size to
* exceed overcommit. There are few sane options here. Since
* alloc_surplus_hugetlb_folio() is checking the global counter,
* though, we'll note that we're not allowed to exceed surplus
* and won't grow the pool anywhere else. Not until one of the
* sysctls are changed, or the surplus pages go out of use.
*/
min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages;
min_count = max(count, min_count);
try_to_free_low(h, min_count, nodes_allowed);
/*
* Collect pages to be removed on list without dropping lock
*/
while (min_count < persistent_huge_pages(h)) {
folio = remove_pool_hugetlb_folio(h, nodes_allowed, 0);
if (!folio)
break;
list_add(&folio->lru, &page_list);
}
/* free the pages after dropping lock */
spin_unlock_irq(&hugetlb_lock);
update_and_free_pages_bulk(h, &page_list);
flush_free_hpage_work(h);
spin_lock_irq(&hugetlb_lock);
while (count < persistent_huge_pages(h)) {
if (!adjust_pool_surplus(h, nodes_allowed, 1))
break;
}
out:
h->max_huge_pages = persistent_huge_pages(h);
spin_unlock_irq(&hugetlb_lock);
mutex_unlock(&h->resize_lock);
NODEMASK_FREE(node_alloc_noretry);
return 0;
}
static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio)
{
int i, nid = folio_nid(folio);
struct hstate *target_hstate;
struct page *subpage;
struct folio *inner_folio;
int rc = 0;
target_hstate = size_to_hstate(PAGE_SIZE << h->demote_order);
remove_hugetlb_folio_for_demote(h, folio, false);
spin_unlock_irq(&hugetlb_lock);
/*
* If vmemmap already existed for folio, the remove routine above would
* have cleared the hugetlb folio flag. Hence the folio is technically
* no longer a hugetlb folio. hugetlb_vmemmap_restore_folio can only be
* passed hugetlb folios and will BUG otherwise.
*/
if (folio_test_hugetlb(folio)) {
rc = hugetlb_vmemmap_restore_folio(h, folio);
if (rc) {
/* Allocation of vmemmmap failed, we can not demote folio */
spin_lock_irq(&hugetlb_lock);
folio_ref_unfreeze(folio, 1);
add_hugetlb_folio(h, folio, false);
return rc;
}
}
/*
* Use destroy_compound_hugetlb_folio_for_demote for all huge page
* sizes as it will not ref count folios.
*/
destroy_compound_hugetlb_folio_for_demote(folio, huge_page_order(h));
/*
* Taking target hstate mutex synchronizes with set_max_huge_pages.
* Without the mutex, pages added to target hstate could be marked
* as surplus.
*
* Note that we already hold h->resize_lock. To prevent deadlock,
* use the convention of always taking larger size hstate mutex first.
*/
mutex_lock(&target_hstate->resize_lock);
for (i = 0; i < pages_per_huge_page(h);
i += pages_per_huge_page(target_hstate)) {
subpage = folio_page(folio, i);
inner_folio = page_folio(subpage);
if (hstate_is_gigantic(target_hstate))
prep_compound_gigantic_folio_for_demote(inner_folio,
target_hstate->order);
else
prep_compound_page(subpage, target_hstate->order);
folio_change_private(inner_folio, NULL);
prep_new_hugetlb_folio(target_hstate, inner_folio, nid);
free_huge_folio(inner_folio);
}
mutex_unlock(&target_hstate->resize_lock);
spin_lock_irq(&hugetlb_lock);
/*
* Not absolutely necessary, but for consistency update max_huge_pages
* based on pool changes for the demoted page.
*/
h->max_huge_pages--;
target_hstate->max_huge_pages +=
pages_per_huge_page(h) / pages_per_huge_page(target_hstate);
return rc;
}
static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed)
__must_hold(&hugetlb_lock)
{
int nr_nodes, node;
struct folio *folio;
lockdep_assert_held(&hugetlb_lock);
/* We should never get here if no demote order */
if (!h->demote_order) {
pr_warn("HugeTLB: NULL demote order passed to demote_pool_huge_page.\n");
return -EINVAL; /* internal error */
}
for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) {
list_for_each_entry(folio, &h->hugepage_freelists[node], lru) {
if (folio_test_hwpoison(folio))
continue;
return demote_free_hugetlb_folio(h, folio);
}
}
/*
* Only way to get here is if all pages on free lists are poisoned.
* Return -EBUSY so that caller will not retry.
*/
return -EBUSY;
}
#define HSTATE_ATTR_RO(_name) \
static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
#define HSTATE_ATTR_WO(_name) \
static struct kobj_attribute _name##_attr = __ATTR_WO(_name)
#define HSTATE_ATTR(_name) \
static struct kobj_attribute _name##_attr = __ATTR_RW(_name)
static struct kobject *hugepages_kobj;
static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE];
static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp);
static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp)
{
int i;
for (i = 0; i < HUGE_MAX_HSTATE; i++)
if (hstate_kobjs[i] == kobj) {
if (nidp)
*nidp = NUMA_NO_NODE;
return &hstates[i];
}
return kobj_to_node_hstate(kobj, nidp);
}
static ssize_t nr_hugepages_show_common(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h;
unsigned long nr_huge_pages;
int nid;
h = kobj_to_hstate(kobj, &nid);
if (nid == NUMA_NO_NODE)
nr_huge_pages = h->nr_huge_pages;
else
nr_huge_pages = h->nr_huge_pages_node[nid];
return sysfs_emit(buf, "%lu\n", nr_huge_pages);
}
static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
struct hstate *h, int nid,
unsigned long count, size_t len)
{
int err;
nodemask_t nodes_allowed, *n_mask;
if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
return -EINVAL;
if (nid == NUMA_NO_NODE) {
/*
* global hstate attribute
*/
if (!(obey_mempolicy &&
init_nodemask_of_mempolicy(&nodes_allowed)))
n_mask = &node_states[N_MEMORY];
else
n_mask = &nodes_allowed;
} else {
/*
* Node specific request. count adjustment happens in
* set_max_huge_pages() after acquiring hugetlb_lock.
*/
init_nodemask_of_node(&nodes_allowed, nid);
n_mask = &nodes_allowed;
}
err = set_max_huge_pages(h, count, nid, n_mask);
return err ? err : len;
}
static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
struct kobject *kobj, const char *buf,
size_t len)
{
struct hstate *h;
unsigned long count;
int nid;
int err;
err = kstrtoul(buf, 10, &count);
if (err)
return err;
h = kobj_to_hstate(kobj, &nid);
return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len);
}
static ssize_t nr_hugepages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
return nr_hugepages_show_common(kobj, attr, buf);
}
static ssize_t nr_hugepages_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t len)
{
return nr_hugepages_store_common(false, kobj, buf, len);
}
HSTATE_ATTR(nr_hugepages);
#ifdef CONFIG_NUMA
/*
* hstate attribute for optionally mempolicy-based constraint on persistent
* huge page alloc/free.
*/
static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj,
struct kobj_attribute *attr,
char *buf)
{
return nr_hugepages_show_common(kobj, attr, buf);
}
static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t len)
{
return nr_hugepages_store_common(true, kobj, buf, len);
}
HSTATE_ATTR(nr_hugepages_mempolicy);
#endif
static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h = kobj_to_hstate(kobj, NULL);
return sysfs_emit(buf, "%lu\n", h->nr_overcommit_huge_pages);
}
static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
int err;
unsigned long input;
struct hstate *h = kobj_to_hstate(kobj, NULL);
if (hstate_is_gigantic(h))
return -EINVAL;
err = kstrtoul(buf, 10, &input);
if (err)
return err;
spin_lock_irq(&hugetlb_lock);
h->nr_overcommit_huge_pages = input;
spin_unlock_irq(&hugetlb_lock);
return count;
}
HSTATE_ATTR(nr_overcommit_hugepages);
static ssize_t free_hugepages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h;
unsigned long free_huge_pages;
int nid;
h = kobj_to_hstate(kobj, &nid);
if (nid == NUMA_NO_NODE)
free_huge_pages = h->free_huge_pages;
else
free_huge_pages = h->free_huge_pages_node[nid];
return sysfs_emit(buf, "%lu\n", free_huge_pages);
}
HSTATE_ATTR_RO(free_hugepages);
static ssize_t resv_hugepages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h = kobj_to_hstate(kobj, NULL);
return sysfs_emit(buf, "%lu\n", h->resv_huge_pages);
}
HSTATE_ATTR_RO(resv_hugepages);
static ssize_t surplus_hugepages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h;
unsigned long surplus_huge_pages;
int nid;
h = kobj_to_hstate(kobj, &nid);
if (nid == NUMA_NO_NODE)
surplus_huge_pages = h->surplus_huge_pages;
else
surplus_huge_pages = h->surplus_huge_pages_node[nid];
return sysfs_emit(buf, "%lu\n", surplus_huge_pages);
}
HSTATE_ATTR_RO(surplus_hugepages);
static ssize_t demote_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t len)
{
unsigned long nr_demote;
unsigned long nr_available;
nodemask_t nodes_allowed, *n_mask;
struct hstate *h;
int err;
int nid;
err = kstrtoul(buf, 10, &nr_demote);
if (err)
return err;
h = kobj_to_hstate(kobj, &nid);
if (nid != NUMA_NO_NODE) {
init_nodemask_of_node(&nodes_allowed, nid);
n_mask = &nodes_allowed;
} else {
n_mask = &node_states[N_MEMORY];
}
/* Synchronize with other sysfs operations modifying huge pages */
mutex_lock(&h->resize_lock);
spin_lock_irq(&hugetlb_lock);
while (nr_demote) {
/*
* Check for available pages to demote each time thorough the
* loop as demote_pool_huge_page will drop hugetlb_lock.
*/
if (nid != NUMA_NO_NODE)
nr_available = h->free_huge_pages_node[nid];
else
nr_available = h->free_huge_pages;
nr_available -= h->resv_huge_pages;
if (!nr_available)
break;
err = demote_pool_huge_page(h, n_mask);
if (err)
break;
nr_demote--;
}
spin_unlock_irq(&hugetlb_lock);
mutex_unlock(&h->resize_lock);
if (err)
return err;
return len;
}
HSTATE_ATTR_WO(demote);
static ssize_t demote_size_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct hstate *h = kobj_to_hstate(kobj, NULL);
unsigned long demote_size = (PAGE_SIZE << h->demote_order) / SZ_1K;
return sysfs_emit(buf, "%lukB\n", demote_size);
}
static ssize_t demote_size_store(struct kobject *kobj,
struct kobj_attribute *attr,
const char *buf, size_t count)
{
struct hstate *h, *demote_hstate;
unsigned long demote_size;
unsigned int demote_order;
demote_size = (unsigned long)memparse(buf, NULL);
demote_hstate = size_to_hstate(demote_size);
if (!demote_hstate)
return -EINVAL;
demote_order = demote_hstate->order;
if (demote_order < HUGETLB_PAGE_ORDER)
return -EINVAL;
/* demote order must be smaller than hstate order */
h = kobj_to_hstate(kobj, NULL);
if (demote_order >= h->order)
return -EINVAL;
/* resize_lock synchronizes access to demote size and writes */
mutex_lock(&h->resize_lock);
h->demote_order = demote_order;
mutex_unlock(&h->resize_lock);
return count;
}
HSTATE_ATTR(demote_size);
static struct attribute *hstate_attrs[] = {
&nr_hugepages_attr.attr,
&nr_overcommit_hugepages_attr.attr,
&free_hugepages_attr.attr,
&resv_hugepages_attr.attr,
&surplus_hugepages_attr.attr,
#ifdef CONFIG_NUMA
&nr_hugepages_mempolicy_attr.attr,
#endif
NULL,
};
static const struct attribute_group hstate_attr_group = {
.attrs = hstate_attrs,
};
static struct attribute *hstate_demote_attrs[] = {
&demote_size_attr.attr,
&demote_attr.attr,
NULL,
};
static const struct attribute_group hstate_demote_attr_group = {
.attrs = hstate_demote_attrs,
};
static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
struct kobject **hstate_kobjs,
const struct attribute_group *hstate_attr_group)
{
int retval;
int hi = hstate_index(h);
hstate_kobjs[hi] = kobject_create_and_add(h->name, parent);
if (!hstate_kobjs[hi])
return -ENOMEM;
retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group);
if (retval) {
kobject_put(hstate_kobjs[hi]);
hstate_kobjs[hi] = NULL;
return retval;
}
if (h->demote_order) {
retval = sysfs_create_group(hstate_kobjs[hi],
&hstate_demote_attr_group);
if (retval) {
pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
kobject_put(hstate_kobjs[hi]);
hstate_kobjs[hi] = NULL;
return retval;
}
}
return 0;
}
#ifdef CONFIG_NUMA
static bool hugetlb_sysfs_initialized __ro_after_init;
/*
* node_hstate/s - associate per node hstate attributes, via their kobjects,
* with node devices in node_devices[] using a parallel array. The array
* index of a node device or _hstate == node id.
* This is here to avoid any static dependency of the node device driver, in
* the base kernel, on the hugetlb module.
*/
struct node_hstate {
struct kobject *hugepages_kobj;
struct kobject *hstate_kobjs[HUGE_MAX_HSTATE];
};
static struct node_hstate node_hstates[MAX_NUMNODES];
/*
* A subset of global hstate attributes for node devices
*/
static struct attribute *per_node_hstate_attrs[] = {
&nr_hugepages_attr.attr,
&free_hugepages_attr.attr,
&surplus_hugepages_attr.attr,
NULL,
};
static const struct attribute_group per_node_hstate_attr_group = {
.attrs = per_node_hstate_attrs,
};
/*
* kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj.
* Returns node id via non-NULL nidp.
*/
static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp)
{
int nid;
for (nid = 0; nid < nr_node_ids; nid++) {
struct node_hstate *nhs = &node_hstates[nid];
int i;
for (i = 0; i < HUGE_MAX_HSTATE; i++)
if (nhs->hstate_kobjs[i] == kobj) {
if (nidp)
*nidp = nid;
return &hstates[i];
}
}
BUG();
return NULL;
}
/*
* Unregister hstate attributes from a single node device.
* No-op if no hstate attributes attached.
*/
void hugetlb_unregister_node(struct node *node)
{
struct hstate *h;
struct node_hstate *nhs = &node_hstates[node->dev.id];
if (!nhs->hugepages_kobj)
return; /* no hstate attributes */
for_each_hstate(h) {
int idx = hstate_index(h);
struct kobject *hstate_kobj = nhs->hstate_kobjs[idx];
if (!hstate_kobj)
continue;
if (h->demote_order)
sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group);
sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group);
kobject_put(hstate_kobj);
nhs->hstate_kobjs[idx] = NULL;
}
kobject_put(nhs->hugepages_kobj);
nhs->hugepages_kobj = NULL;
}
/*
* Register hstate attributes for a single node device.
* No-op if attributes already registered.
*/
void hugetlb_register_node(struct node *node)
{
struct hstate *h;
struct node_hstate *nhs = &node_hstates[node->dev.id];
int err;
if (!hugetlb_sysfs_initialized)
return;
if (nhs->hugepages_kobj)
return; /* already allocated */
nhs->hugepages_kobj = kobject_create_and_add("hugepages",
&node->dev.kobj);
if (!nhs->hugepages_kobj)
return;
for_each_hstate(h) {
err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj,
nhs->hstate_kobjs,
&per_node_hstate_attr_group);
if (err) {
pr_err("HugeTLB: Unable to add hstate %s for node %d\n",
h->name, node->dev.id);
hugetlb_unregister_node(node);
break;
}
}
}
/*
* hugetlb init time: register hstate attributes for all registered node
* devices of nodes that have memory. All on-line nodes should have
* registered their associated device by this time.
*/
static void __init hugetlb_register_all_nodes(void)
{
int nid;
for_each_online_node(nid)
hugetlb_register_node(node_devices[nid]);
}
#else /* !CONFIG_NUMA */
static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp)
{
BUG();
if (nidp)
*nidp = -1;
return NULL;
}
static void hugetlb_register_all_nodes(void) { }
#endif
#ifdef CONFIG_CMA
static void __init hugetlb_cma_check(void);
#else
static inline __init void hugetlb_cma_check(void)
{
}
#endif
static void __init hugetlb_sysfs_init(void)
{
struct hstate *h;
int err;
hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj);
if (!hugepages_kobj)
return;
for_each_hstate(h) {
err = hugetlb_sysfs_add_hstate(h, hugepages_kobj,
hstate_kobjs, &hstate_attr_group);
if (err)
pr_err("HugeTLB: Unable to add hstate %s", h->name);
}
#ifdef CONFIG_NUMA
hugetlb_sysfs_initialized = true;
#endif
hugetlb_register_all_nodes();
}
#ifdef CONFIG_SYSCTL
static void hugetlb_sysctl_init(void);
#else
static inline void hugetlb_sysctl_init(void) { }
#endif
static int __init hugetlb_init(void)
{
int i;
BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE <
__NR_HPAGEFLAGS);
if (!hugepages_supported()) {
if (hugetlb_max_hstate || default_hstate_max_huge_pages)
pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n");
return 0;
}
/*
* Make sure HPAGE_SIZE (HUGETLB_PAGE_ORDER) hstate exists. Some
* architectures depend on setup being done here.
*/
hugetlb_add_hstate(HUGETLB_PAGE_ORDER);
if (!parsed_default_hugepagesz) {
/*
* If we did not parse a default huge page size, set
* default_hstate_idx to HPAGE_SIZE hstate. And, if the
* number of huge pages for this default size was implicitly
* specified, set that here as well.
* Note that the implicit setting will overwrite an explicit
* setting. A warning will be printed in this case.
*/
default_hstate_idx = hstate_index(size_to_hstate(HPAGE_SIZE));
if (default_hstate_max_huge_pages) {
if (default_hstate.max_huge_pages) {
char buf[32];
string_get_size(huge_page_size(&default_hstate),
1, STRING_UNITS_2, buf, 32);
pr_warn("HugeTLB: Ignoring hugepages=%lu associated with %s page size\n",
default_hstate.max_huge_pages, buf);
pr_warn("HugeTLB: Using hugepages=%lu for number of default huge pages\n",
default_hstate_max_huge_pages);
}
default_hstate.max_huge_pages =
default_hstate_max_huge_pages;
for_each_online_node(i)
default_hstate.max_huge_pages_node[i] =
default_hugepages_in_node[i];
}
}
hugetlb_cma_check();
hugetlb_init_hstates();
gather_bootmem_prealloc();
report_hugepages();
hugetlb_sysfs_init();
hugetlb_cgroup_file_init();
hugetlb_sysctl_init();
#ifdef CONFIG_SMP
num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus());
#else
num_fault_mutexes = 1;
#endif
hugetlb_fault_mutex_table =
kmalloc_array(num_fault_mutexes, sizeof(struct mutex),
GFP_KERNEL);
BUG_ON(!hugetlb_fault_mutex_table);
for (i = 0; i < num_fault_mutexes; i++)
mutex_init(&hugetlb_fault_mutex_table[i]);
return 0;
}
subsys_initcall(hugetlb_init);
/* Overwritten by architectures with more huge page sizes */
bool __init __attribute((weak)) arch_hugetlb_valid_size(unsigned long size)
{
return size == HPAGE_SIZE;
}
void __init hugetlb_add_hstate(unsigned int order)
{
struct hstate *h;
unsigned long i;
if (size_to_hstate(PAGE_SIZE << order)) {
return;
}
BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE);
BUG_ON(order < order_base_2(__NR_USED_SUBPAGE));
h = &hstates[hugetlb_max_hstate++];
mutex_init(&h->resize_lock);
h->order = order;
h->mask = ~(huge_page_size(h) - 1);
for (i = 0; i < MAX_NUMNODES; ++i)
INIT_LIST_HEAD(&h->hugepage_freelists[i]);
INIT_LIST_HEAD(&h->hugepage_activelist);
h->next_nid_to_alloc = first_memory_node;
h->next_nid_to_free = first_memory_node;
snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB",
huge_page_size(h)/SZ_1K);
parsed_hstate = h;
}
bool __init __weak hugetlb_node_alloc_supported(void)
{
return true;
}
static void __init hugepages_clear_pages_in_node(void)
{
if (!hugetlb_max_hstate) {
default_hstate_max_huge_pages = 0;
memset(default_hugepages_in_node, 0,
sizeof(default_hugepages_in_node));
} else {
parsed_hstate->max_huge_pages = 0;
memset(parsed_hstate->max_huge_pages_node, 0,
sizeof(parsed_hstate->max_huge_pages_node));
}
}
/*
* hugepages command line processing
* hugepages normally follows a valid hugepagsz or default_hugepagsz
* specification. If not, ignore the hugepages value. hugepages can also
* be the first huge page command line option in which case it implicitly
* specifies the number of huge pages for the default size.
*/
static int __init hugepages_setup(char *s)
{
unsigned long *mhp;
static unsigned long *last_mhp;
int node = NUMA_NO_NODE;
int count;
unsigned long tmp;
char *p = s;
if (!parsed_valid_hugepagesz) {
pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s);
parsed_valid_hugepagesz = true;
return 1;
}
/*
* !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter
* yet, so this hugepages= parameter goes to the "default hstate".
* Otherwise, it goes with the previously parsed hugepagesz or
* default_hugepagesz.
*/
else if (!hugetlb_max_hstate)
mhp = &default_hstate_max_huge_pages;
else
mhp = &parsed_hstate->max_huge_pages;
if (mhp == last_mhp) {
pr_warn("HugeTLB: hugepages= specified twice without interleaving hugepagesz=, ignoring hugepages=%s\n", s);
return 1;
}
while (*p) {
count = 0;
if (sscanf(p, "%lu%n", &tmp, &count) != 1)
goto invalid;
/* Parameter is node format */
if (p[count] == ':') {
if (!hugetlb_node_alloc_supported()) {
pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n");
return 1;
}
if (tmp >= MAX_NUMNODES || !node_online(tmp))
goto invalid;
node = array_index_nospec(tmp, MAX_NUMNODES);
p += count + 1;
/* Parse hugepages */
if (sscanf(p, "%lu%n", &tmp, &count) != 1)
goto invalid;
if (!hugetlb_max_hstate)
default_hugepages_in_node[node] = tmp;
else
parsed_hstate->max_huge_pages_node[node] = tmp;
*mhp += tmp;
/* Go to parse next node*/
if (p[count] == ',')
p += count + 1;
else
break;
} else {
if (p != s)
goto invalid;
*mhp = tmp;
break;
}
}
/*
* Global state is always initialized later in hugetlb_init.
* But we need to allocate gigantic hstates here early to still
* use the bootmem allocator.
*/
if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate))
hugetlb_hstate_alloc_pages(parsed_hstate);
last_mhp = mhp;
return 1;
invalid:
pr_warn("HugeTLB: Invalid hugepages parameter %s\n", p);
hugepages_clear_pages_in_node();
return 1;
}
__setup("hugepages=", hugepages_setup);
/*
* hugepagesz command line processing
* A specific huge page size can only be specified once with hugepagesz.
* hugepagesz is followed by hugepages on the command line. The global
* variable 'parsed_valid_hugepagesz' is used to determine if prior
* hugepagesz argument was valid.
*/
static int __init hugepagesz_setup(char *s)
{
unsigned long size;
struct hstate *h;
parsed_valid_hugepagesz = false;
size = (unsigned long)memparse(s, NULL);
if (!arch_hugetlb_valid_size(size)) {
pr_err("HugeTLB: unsupported hugepagesz=%s\n", s);
return 1;
}
h = size_to_hstate(size);
if (h) {
/*
* hstate for this size already exists. This is normally
* an error, but is allowed if the existing hstate is the
* default hstate. More specifically, it is only allowed if
* the number of huge pages for the default hstate was not
* previously specified.
*/
if (!parsed_default_hugepagesz || h != &default_hstate ||
default_hstate.max_huge_pages) {
pr_warn("HugeTLB: hugepagesz=%s specified twice, ignoring\n", s);
return 1;
}
/*
* No need to call hugetlb_add_hstate() as hstate already
* exists. But, do set parsed_hstate so that a following
* hugepages= parameter will be applied to this hstate.
*/
parsed_hstate = h;
parsed_valid_hugepagesz = true;
return 1;
}
hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT);
parsed_valid_hugepagesz = true;
return 1;
}
__setup("hugepagesz=", hugepagesz_setup);
/*
* default_hugepagesz command line input
* Only one instance of default_hugepagesz allowed on command line.
*/
static int __init default_hugepagesz_setup(char *s)
{
unsigned long size;
int i;
parsed_valid_hugepagesz = false;
if (parsed_default_hugepagesz) {
pr_err("HugeTLB: default_hugepagesz previously specified, ignoring %s\n", s);
return 1;
}
size = (unsigned long)memparse(s, NULL);
if (!arch_hugetlb_valid_size(size)) {
pr_err("HugeTLB: unsupported default_hugepagesz=%s\n", s);
return 1;
}
hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT);
parsed_valid_hugepagesz = true;
parsed_default_hugepagesz = true;
default_hstate_idx = hstate_index(size_to_hstate(size));
/*
* The number of default huge pages (for this size) could have been
* specified as the first hugetlb parameter: hugepages=X. If so,
* then default_hstate_max_huge_pages is set. If the default huge
* page size is gigantic (> MAX_PAGE_ORDER), then the pages must be
* allocated here from bootmem allocator.
*/
if (default_hstate_max_huge_pages) {
default_hstate.max_huge_pages = default_hstate_max_huge_pages;
for_each_online_node(i)
default_hstate.max_huge_pages_node[i] =
default_hugepages_in_node[i];
if (hstate_is_gigantic(&default_hstate))
hugetlb_hstate_alloc_pages(&default_hstate);
default_hstate_max_huge_pages = 0;
}
return 1;
}
__setup("default_hugepagesz=", default_hugepagesz_setup);
static nodemask_t *policy_mbind_nodemask(gfp_t gfp)
{
#ifdef CONFIG_NUMA
struct mempolicy *mpol = get_task_policy(current);
/*
* Only enforce MPOL_BIND policy which overlaps with cpuset policy
* (from policy_nodemask) specifically for hugetlb case
*/
if (mpol->mode == MPOL_BIND &&
(apply_policy_zone(mpol, gfp_zone(gfp)) &&
cpuset_nodemask_valid_mems_allowed(&mpol->nodes)))
return &mpol->nodes;
#endif
return NULL;
}
static unsigned int allowed_mems_nr(struct hstate *h)
{
int node;
unsigned int nr = 0;
nodemask_t *mbind_nodemask;
unsigned int *array = h->free_huge_pages_node;
gfp_t gfp_mask = htlb_alloc_mask(h);
mbind_nodemask = policy_mbind_nodemask(gfp_mask);
for_each_node_mask(node, cpuset_current_mems_allowed) {
if (!mbind_nodemask || node_isset(node, *mbind_nodemask))
nr += array[node];
}
return nr;
}
#ifdef CONFIG_SYSCTL
static int proc_hugetlb_doulongvec_minmax(struct ctl_table *table, int write,
void *buffer, size_t *length,
loff_t *ppos, unsigned long *out)
{
struct ctl_table dup_table;
/*
* In order to avoid races with __do_proc_doulongvec_minmax(), we
* can duplicate the @table and alter the duplicate of it.
*/
dup_table = *table;
dup_table.data = out;
return proc_doulongvec_minmax(&dup_table, write, buffer, length, ppos);
}
static int hugetlb_sysctl_handler_common(bool obey_mempolicy,
struct ctl_table *table, int write,
void *buffer, size_t *length, loff_t *ppos)
{
struct hstate *h = &default_hstate;
unsigned long tmp = h->max_huge_pages;
int ret;
if (!hugepages_supported())
return -EOPNOTSUPP;
ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos,
&tmp);
if (ret)
goto out;
if (write)
ret = __nr_hugepages_store_common(obey_mempolicy, h,
NUMA_NO_NODE, tmp, *length);
out:
return ret;
}
static int hugetlb_sysctl_handler(struct ctl_table *table, int write,
void *buffer, size_t *length, loff_t *ppos)
{
return hugetlb_sysctl_handler_common(false, table, write,
buffer, length, ppos);
}
#ifdef CONFIG_NUMA
static int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write,
void *buffer, size_t *length, loff_t *ppos)
{
return hugetlb_sysctl_handler_common(true, table, write,
buffer, length, ppos);
}
#endif /* CONFIG_NUMA */
static int hugetlb_overcommit_handler(struct ctl_table *table, int write,
void *buffer, size_t *length, loff_t *ppos)
{
struct hstate *h = &default_hstate;
unsigned long tmp;
int ret;
if (!hugepages_supported())
return -EOPNOTSUPP;
tmp = h->nr_overcommit_huge_pages;
if (write && hstate_is_gigantic(h))
return -EINVAL;
ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos,
&tmp);
if (ret)
goto out;
if (write) {
spin_lock_irq(&hugetlb_lock);
h->nr_overcommit_huge_pages = tmp;
spin_unlock_irq(&hugetlb_lock);
}
out:
return ret;
}
static struct ctl_table hugetlb_table[] = {
{
.procname = "nr_hugepages",
.data = NULL,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = hugetlb_sysctl_handler,
},
#ifdef CONFIG_NUMA
{
.procname = "nr_hugepages_mempolicy",
.data = NULL,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &hugetlb_mempolicy_sysctl_handler,
},
#endif
{
.procname = "hugetlb_shm_group",
.data = &sysctl_hugetlb_shm_group,
.maxlen = sizeof(gid_t),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "nr_overcommit_hugepages",
.data = NULL,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = hugetlb_overcommit_handler,
},
{ }
};
static void hugetlb_sysctl_init(void)
{
register_sysctl_init("vm", hugetlb_table);
}
#endif /* CONFIG_SYSCTL */
void hugetlb_report_meminfo(struct seq_file *m)
{
struct hstate *h;
unsigned long total = 0;
if (!hugepages_supported())
return;
for_each_hstate(h) {
unsigned long count = h->nr_huge_pages;
total += huge_page_size(h) * count;
if (h == &default_hstate)
seq_printf(m,
"HugePages_Total: %5lu\n"
"HugePages_Free: %5lu\n"
"HugePages_Rsvd: %5lu\n"
"HugePages_Surp: %5lu\n"
"Hugepagesize: %8lu kB\n",
count,
h->free_huge_pages,
h->resv_huge_pages,
h->surplus_huge_pages,
huge_page_size(h) / SZ_1K);
}
seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K);
}
int hugetlb_report_node_meminfo(char *buf, int len, int nid)
{
struct hstate *h = &default_hstate;
if (!hugepages_supported())
return 0;
return sysfs_emit_at(buf, len,
"Node %d HugePages_Total: %5u\n"
"Node %d HugePages_Free: %5u\n"
"Node %d HugePages_Surp: %5u\n",
nid, h->nr_huge_pages_node[nid],
nid, h->free_huge_pages_node[nid],
nid, h->surplus_huge_pages_node[nid]);
}
void hugetlb_show_meminfo_node(int nid)
{
struct hstate *h;
if (!hugepages_supported())
return;
for_each_hstate(h)
printk("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n",
nid,
h->nr_huge_pages_node[nid],
h->free_huge_pages_node[nid],
h->surplus_huge_pages_node[nid],
huge_page_size(h) / SZ_1K);
}
void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm)
{
seq_printf(m, "HugetlbPages:\t%8lu kB\n",
K(atomic_long_read(&mm->hugetlb_usage)));
}
/* Return the number pages of memory we physically have, in PAGE_SIZE units. */
unsigned long hugetlb_total_pages(void)
{
struct hstate *h;
unsigned long nr_total_pages = 0;
for_each_hstate(h)
nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h);
return nr_total_pages;
}
static int hugetlb_acct_memory(struct hstate *h, long delta)
{
int ret = -ENOMEM;
if (!delta)
return 0;
spin_lock_irq(&hugetlb_lock);
/*
* When cpuset is configured, it breaks the strict hugetlb page
* reservation as the accounting is done on a global variable. Such
* reservation is completely rubbish in the presence of cpuset because
* the reservation is not checked against page availability for the
* current cpuset. Application can still potentially OOM'ed by kernel
* with lack of free htlb page in cpuset that the task is in.
* Attempt to enforce strict accounting with cpuset is almost
* impossible (or too ugly) because cpuset is too fluid that
* task or memory node can be dynamically moved between cpusets.
*
* The change of semantics for shared hugetlb mapping with cpuset is
* undesirable. However, in order to preserve some of the semantics,
* we fall back to check against current free page availability as
* a best attempt and hopefully to minimize the impact of changing
* semantics that cpuset has.
*
* Apart from cpuset, we also have memory policy mechanism that
* also determines from which node the kernel will allocate memory
* in a NUMA system. So similar to cpuset, we also should consider
* the memory policy of the current task. Similar to the description
* above.
*/
if (delta > 0) {
if (gather_surplus_pages(h, delta) < 0)
goto out;
if (delta > allowed_mems_nr(h)) {
return_unused_surplus_pages(h, delta);
goto out;
}
}
ret = 0;
if (delta < 0)
return_unused_surplus_pages(h, (unsigned long) -delta);
out:
spin_unlock_irq(&hugetlb_lock);
return ret;
}
static void hugetlb_vm_op_open(struct vm_area_struct *vma)
{
struct resv_map *resv = vma_resv_map(vma);
/*
* HPAGE_RESV_OWNER indicates a private mapping.
* This new VMA should share its siblings reservation map if present.
* The VMA will only ever have a valid reservation map pointer where
* it is being copied for another still existing VMA. As that VMA
* has a reference to the reservation map it cannot disappear until
* after this open call completes. It is therefore safe to take a
* new reference here without additional locking.
*/
if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
resv_map_dup_hugetlb_cgroup_uncharge_info(resv);
kref_get(&resv->refs);
}
/*
* vma_lock structure for sharable mappings is vma specific.
* Clear old pointer (if copied via vm_area_dup) and allocate
* new structure. Before clearing, make sure vma_lock is not
* for this vma.
*/
if (vma->vm_flags & VM_MAYSHARE) {
struct hugetlb_vma_lock *vma_lock = vma->vm_private_data;
if (vma_lock) {
if (vma_lock->vma != vma) {
vma->vm_private_data = NULL;
hugetlb_vma_lock_alloc(vma);
} else
pr_warn("HugeTLB: vma_lock already exists in %s.\n", __func__);
} else
hugetlb_vma_lock_alloc(vma);
}
}
static void hugetlb_vm_op_close(struct vm_area_struct *vma)
{
struct hstate *h = hstate_vma(vma);
struct resv_map *resv;
struct hugepage_subpool *spool = subpool_vma(vma);
unsigned long reserve, start, end;
long gbl_reserve;
hugetlb_vma_lock_free(vma);
resv = vma_resv_map(vma);
if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER))
return;
start = vma_hugecache_offset(h, vma, vma->vm_start);
end = vma_hugecache_offset(h, vma, vma->vm_end);
reserve = (end - start) - region_count(resv, start, end);
hugetlb_cgroup_uncharge_counter(resv, start, end);
if (reserve) {
/*
* Decrement reserve counts. The global reserve count may be
* adjusted if the subpool has a minimum size.
*/
gbl_reserve = hugepage_subpool_put_pages(spool, reserve);
hugetlb_acct_memory(h, -gbl_reserve);
}
kref_put(&resv->refs, resv_map_release);
}
static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr)
{
if (addr & ~(huge_page_mask(hstate_vma(vma))))
return -EINVAL;
/*
* PMD sharing is only possible for PUD_SIZE-aligned address ranges
* in HugeTLB VMAs. If we will lose PUD_SIZE alignment due to this
* split, unshare PMDs in the PUD_SIZE interval surrounding addr now.
*/
if (addr & ~PUD_MASK) {
/*
* hugetlb_vm_op_split is called right before we attempt to
* split the VMA. We will need to unshare PMDs in the old and
* new VMAs, so let's unshare before we split.
*/
unsigned long floor = addr & PUD_MASK;
unsigned long ceil = floor + PUD_SIZE;
if (floor >= vma->vm_start && ceil <= vma->vm_end)
hugetlb_unshare_pmds(vma, floor, ceil);
}
return 0;
}
static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma)
{
return huge_page_size(hstate_vma(vma));
}
/*
* We cannot handle pagefaults against hugetlb pages at all. They cause
* handle_mm_fault() to try to instantiate regular-sized pages in the
* hugepage VMA. do_page_fault() is supposed to trap this, so BUG is we get
* this far.
*/
static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf)
{
BUG();
return 0;
}
/*
* When a new function is introduced to vm_operations_struct and added
* to hugetlb_vm_ops, please consider adding the function to shm_vm_ops.
* This is because under System V memory model, mappings created via
* shmget/shmat with "huge page" specified are backed by hugetlbfs files,
* their original vm_ops are overwritten with shm_vm_ops.
*/
const struct vm_operations_struct hugetlb_vm_ops = {
.fault = hugetlb_vm_op_fault,
.open = hugetlb_vm_op_open,
.close = hugetlb_vm_op_close,
.may_split = hugetlb_vm_op_split,
.pagesize = hugetlb_vm_op_pagesize,
};
static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
int writable)
{
pte_t entry;
unsigned int shift = huge_page_shift(hstate_vma(vma));
if (writable) {
entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page,
vma->vm_page_prot)));
} else {
entry = huge_pte_wrprotect(mk_huge_pte(page,
vma->vm_page_prot));
}
entry = pte_mkyoung(entry);
entry = arch_make_huge_pte(entry, shift, vma->vm_flags);
return entry;
}
static void set_huge_ptep_writable(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
pte_t entry;
entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep)));
if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1))
update_mmu_cache(vma, address, ptep);
}
bool is_hugetlb_entry_migration(pte_t pte)
{
swp_entry_t swp;
if (huge_pte_none(pte) || pte_present(pte))
return false;
swp = pte_to_swp_entry(pte);
if (is_migration_entry(swp))
return true;
else
return false;
}
bool is_hugetlb_entry_hwpoisoned(pte_t pte)
{
swp_entry_t swp;
if (huge_pte_none(pte) || pte_present(pte))
return false;
swp = pte_to_swp_entry(pte);
if (is_hwpoison_entry(swp))
return true;
else
return false;
}
static void
hugetlb_install_folio(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr,
struct folio *new_folio, pte_t old, unsigned long sz)
{
pte_t newpte = make_huge_pte(vma, &new_folio->page, 1);
__folio_mark_uptodate(new_folio);
hugetlb_add_new_anon_rmap(new_folio, vma, addr);
if (userfaultfd_wp(vma) && huge_pte_uffd_wp(old))
newpte = huge_pte_mkuffd_wp(newpte);
set_huge_pte_at(vma->vm_mm, addr, ptep, newpte, sz);
hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm);
folio_set_hugetlb_migratable(new_folio);
}
int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
struct vm_area_struct *dst_vma,
struct vm_area_struct *src_vma)
{
pte_t *src_pte, *dst_pte, entry;
struct folio *pte_folio;
unsigned long addr;
bool cow = is_cow_mapping(src_vma->vm_flags);
struct hstate *h = hstate_vma(src_vma);
unsigned long sz = huge_page_size(h);
unsigned long npages = pages_per_huge_page(h);
struct mmu_notifier_range range;
unsigned long last_addr_mask;
int ret = 0;
if (cow) {
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, src,
src_vma->vm_start,
src_vma->vm_end);
mmu_notifier_invalidate_range_start(&range);
vma_assert_write_locked(src_vma);
raw_write_seqcount_begin(&src->write_protect_seq);
} else {
/*
* For shared mappings the vma lock must be held before
* calling hugetlb_walk() in the src vma. Otherwise, the
* returned ptep could go away if part of a shared pmd and
* another thread calls huge_pmd_unshare.
*/
hugetlb_vma_lock_read(src_vma);
}
last_addr_mask = hugetlb_mask_last_page(h);
for (addr = src_vma->vm_start; addr < src_vma->vm_end; addr += sz) {
spinlock_t *src_ptl, *dst_ptl;
src_pte = hugetlb_walk(src_vma, addr, sz);
if (!src_pte) {
addr |= last_addr_mask;
continue;
}
dst_pte = huge_pte_alloc(dst, dst_vma, addr, sz);
if (!dst_pte) {
ret = -ENOMEM;
break;
}
/*
* If the pagetables are shared don't copy or take references.
*
* dst_pte == src_pte is the common case of src/dest sharing.
* However, src could have 'unshared' and dst shares with
* another vma. So page_count of ptep page is checked instead
* to reliably determine whether pte is shared.
*/
if (page_count(virt_to_page(dst_pte)) > 1) {
addr |= last_addr_mask;
continue;
}
dst_ptl = huge_pte_lock(h, dst, dst_pte);
src_ptl = huge_pte_lockptr(h, src, src_pte);
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
entry = huge_ptep_get(src_pte);
again:
if (huge_pte_none(entry)) {
/*
* Skip if src entry none.
*/
;
} else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) {
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);
set_huge_pte_at(dst, addr, dst_pte, entry, sz);
} else if (unlikely(is_hugetlb_entry_migration(entry))) {
swp_entry_t swp_entry = pte_to_swp_entry(entry);
bool uffd_wp = pte_swp_uffd_wp(entry);
if (!is_readable_migration_entry(swp_entry) && cow) {
/*
* COW mappings require pages in both
* parent and child to be set to read.
*/
swp_entry = make_readable_migration_entry(
swp_offset(swp_entry));
entry = swp_entry_to_pte(swp_entry);
if (userfaultfd_wp(src_vma) && uffd_wp)
entry = pte_swp_mkuffd_wp(entry);
set_huge_pte_at(src, addr, src_pte, entry, sz);
}
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);
set_huge_pte_at(dst, addr, dst_pte, entry, sz);
} else if (unlikely(is_pte_marker(entry))) {
pte_marker marker = copy_pte_marker(
pte_to_swp_entry(entry), dst_vma);
if (marker)
set_huge_pte_at(dst, addr, dst_pte,
make_pte_marker(marker), sz);
} else {
entry = huge_ptep_get(src_pte);
pte_folio = page_folio(pte_page(entry));
folio_get(pte_folio);
/*
* Failing to duplicate the anon rmap is a rare case
* where we see pinned hugetlb pages while they're
* prone to COW. We need to do the COW earlier during
* fork.
*
* When pre-allocating the page or copying data, we
* need to be without the pgtable locks since we could
* sleep during the process.
*/
if (!folio_test_anon(pte_folio)) {
hugetlb_add_file_rmap(pte_folio);
} else if (hugetlb_try_dup_anon_rmap(pte_folio, src_vma)) {
pte_t src_pte_old = entry;
struct folio *new_folio;
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
/* Do not use reserve as it's private owned */
new_folio = alloc_hugetlb_folio(dst_vma, addr, 1);
if (IS_ERR(new_folio)) {
folio_put(pte_folio);
ret = PTR_ERR(new_folio);
break;
}
ret = copy_user_large_folio(new_folio,
pte_folio,
addr, dst_vma);
folio_put(pte_folio);
if (ret) {
folio_put(new_folio);
break;
}
/* Install the new hugetlb folio if src pte stable */
dst_ptl = huge_pte_lock(h, dst, dst_pte);
src_ptl = huge_pte_lockptr(h, src, src_pte);
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
entry = huge_ptep_get(src_pte);
if (!pte_same(src_pte_old, entry)) {
restore_reserve_on_error(h, dst_vma, addr,
new_folio);
folio_put(new_folio);
/* huge_ptep of dst_pte won't change as in child */
goto again;
}
hugetlb_install_folio(dst_vma, dst_pte, addr,
new_folio, src_pte_old, sz);
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
continue;
}
if (cow) {
/*
* No need to notify as we are downgrading page
* table protection not changing it to point
* to a new page.
*
* See Documentation/mm/mmu_notifier.rst
*/
huge_ptep_set_wrprotect(src, addr, src_pte);
entry = huge_pte_wrprotect(entry);
}
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);
set_huge_pte_at(dst, addr, dst_pte, entry, sz);
hugetlb_count_add(npages, dst);
}
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
}
if (cow) {
raw_write_seqcount_end(&src->write_protect_seq);
mmu_notifier_invalidate_range_end(&range);
} else {
hugetlb_vma_unlock_read(src_vma);
}
return ret;
}
static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr,
unsigned long new_addr, pte_t *src_pte, pte_t *dst_pte,
unsigned long sz)
{
struct hstate *h = hstate_vma(vma);
struct mm_struct *mm = vma->vm_mm;
spinlock_t *src_ptl, *dst_ptl;
pte_t pte;
dst_ptl = huge_pte_lock(h, mm, dst_pte);
src_ptl = huge_pte_lockptr(h, mm, src_pte);
/*
* We don't have to worry about the ordering of src and dst ptlocks
* because exclusive mmap_lock (or the i_mmap_lock) prevents deadlock.
*/
if (src_ptl != dst_ptl)
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
pte = huge_ptep_get_and_clear(mm, old_addr, src_pte);
set_huge_pte_at(mm, new_addr, dst_pte, pte, sz);
if (src_ptl != dst_ptl)
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
}
int move_hugetlb_page_tables(struct vm_area_struct *vma,
struct vm_area_struct *new_vma,
unsigned long old_addr, unsigned long new_addr,
unsigned long len)
{
struct hstate *h = hstate_vma(vma);
struct address_space *mapping = vma->vm_file->f_mapping;
unsigned long sz = huge_page_size(h);
struct mm_struct *mm = vma->vm_mm;
unsigned long old_end = old_addr + len;
unsigned long last_addr_mask;
pte_t *src_pte, *dst_pte;
struct mmu_notifier_range range;
bool shared_pmd = false;
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, old_addr,
old_end);
adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end);
/*
* In case of shared PMDs, we should cover the maximum possible
* range.
*/
flush_cache_range(vma, range.start, range.end);
mmu_notifier_invalidate_range_start(&range);
last_addr_mask = hugetlb_mask_last_page(h);
/* Prevent race with file truncation */
hugetlb_vma_lock_write(vma);
i_mmap_lock_write(mapping);
for (; old_addr < old_end; old_addr += sz, new_addr += sz) {
src_pte = hugetlb_walk(vma, old_addr, sz);
if (!src_pte) {
old_addr |= last_addr_mask;
new_addr |= last_addr_mask;
continue;
}
if (huge_pte_none(huge_ptep_get(src_pte)))
continue;
if (huge_pmd_unshare(mm, vma, old_addr, src_pte)) {
shared_pmd = true;
old_addr |= last_addr_mask;
new_addr |= last_addr_mask;
continue;
}
dst_pte = huge_pte_alloc(mm, new_vma, new_addr, sz);
if (!dst_pte)
break;
move_huge_pte(vma, old_addr, new_addr, src_pte, dst_pte, sz);
}
if (shared_pmd)
flush_hugetlb_tlb_range(vma, range.start, range.end);
else
flush_hugetlb_tlb_range(vma, old_end - len, old_end);
mmu_notifier_invalidate_range_end(&range);
i_mmap_unlock_write(mapping);
hugetlb_vma_unlock_write(vma);
return len + old_addr - old_end;
}
void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start, unsigned long end,
struct page *ref_page, zap_flags_t zap_flags)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long address;
pte_t *ptep;
pte_t pte;
spinlock_t *ptl;
struct page *page;
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
bool adjust_reservation = false;
unsigned long last_addr_mask;
bool force_flush = false;
WARN_ON(!is_vm_hugetlb_page(vma));
BUG_ON(start & ~huge_page_mask(h));
BUG_ON(end & ~huge_page_mask(h));
/*
* This is a hugetlb vma, all the pte entries should point
* to huge page.
*/
tlb_change_page_size(tlb, sz);
tlb_start_vma(tlb, vma);
last_addr_mask = hugetlb_mask_last_page(h);
address = start;
for (; address < end; address += sz) {
ptep = hugetlb_walk(vma, address, sz);
if (!ptep) {
address |= last_addr_mask;
continue;
}
ptl = huge_pte_lock(h, mm, ptep);
if (huge_pmd_unshare(mm, vma, address, ptep)) {
spin_unlock(ptl);
tlb_flush_pmd_range(tlb, address & PUD_MASK, PUD_SIZE);
force_flush = true;
address |= last_addr_mask;
continue;
}
pte = huge_ptep_get(ptep);
if (huge_pte_none(pte)) {
spin_unlock(ptl);
continue;
}
/*
* Migrating hugepage or HWPoisoned hugepage is already
* unmapped and its refcount is dropped, so just clear pte here.
*/
if (unlikely(!pte_present(pte))) {
/*
* If the pte was wr-protected by uffd-wp in any of the
* swap forms, meanwhile the caller does not want to
* drop the uffd-wp bit in this zap, then replace the
* pte with a marker.
*/
if (pte_swp_uffd_wp_any(pte) &&
!(zap_flags & ZAP_FLAG_DROP_MARKER))
set_huge_pte_at(mm, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP),
sz);
else
huge_pte_clear(mm, address, ptep, sz);
spin_unlock(ptl);
continue;
}
page = pte_page(pte);
/*
* If a reference page is supplied, it is because a specific
* page is being unmapped, not a range. Ensure the page we
* are about to unmap is the actual page of interest.
*/
if (ref_page) {
if (page != ref_page) {
spin_unlock(ptl);
continue;
}
/*
* Mark the VMA as having unmapped its page so that
* future faults in this VMA will fail rather than
* looking like data was lost
*/
set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED);
}
pte = huge_ptep_get_and_clear(mm, address, ptep);
tlb_remove_huge_tlb_entry(h, tlb, ptep, address);
if (huge_pte_dirty(pte))
set_page_dirty(page);
/* Leave a uffd-wp pte marker if needed */
if (huge_pte_uffd_wp(pte) &&
!(zap_flags & ZAP_FLAG_DROP_MARKER))
set_huge_pte_at(mm, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP),
sz);
hugetlb_count_sub(pages_per_huge_page(h), mm);
hugetlb_remove_rmap(page_folio(page));
/*
* Restore the reservation for anonymous page, otherwise the
* backing page could be stolen by someone.
* If there we are freeing a surplus, do not set the restore
* reservation bit.
*/
if (!h->surplus_huge_pages && __vma_private_lock(vma) &&
folio_test_anon(page_folio(page))) {
folio_set_hugetlb_restore_reserve(page_folio(page));
/* Reservation to be adjusted after the spin lock */
adjust_reservation = true;
}
spin_unlock(ptl);
/*
* Adjust the reservation for the region that will have the
* reserve restored. Keep in mind that vma_needs_reservation() changes
* resv->adds_in_progress if it succeeds. If this is not done,
* do_exit() will not see it, and will keep the reservation
* forever.
*/
if (adjust_reservation && vma_needs_reservation(h, vma, address))
vma_add_reservation(h, vma, address);
tlb_remove_page_size(tlb, page, huge_page_size(h));
/*
* Bail out after unmapping reference page if supplied
*/
if (ref_page)
break;
}
tlb_end_vma(tlb, vma);
/*
* If we unshared PMDs, the TLB flush was not recorded in mmu_gather. We
* could defer the flush until now, since by holding i_mmap_rwsem we
* guaranteed that the last refernece would not be dropped. But we must
* do the flushing before we return, as otherwise i_mmap_rwsem will be
* dropped and the last reference to the shared PMDs page might be
* dropped as well.
*
* In theory we could defer the freeing of the PMD pages as well, but
* huge_pmd_unshare() relies on the exact page_count for the PMD page to
* detect sharing, so we cannot defer the release of the page either.
* Instead, do flush now.
*/
if (force_flush)
tlb_flush_mmu_tlbonly(tlb);
}
void __hugetlb_zap_begin(struct vm_area_struct *vma,
unsigned long *start, unsigned long *end)
{
if (!vma->vm_file) /* hugetlbfs_file_mmap error */
return;
adjust_range_if_pmd_sharing_possible(vma, start, end);
hugetlb_vma_lock_write(vma);
if (vma->vm_file)
i_mmap_lock_write(vma->vm_file->f_mapping);
}
void __hugetlb_zap_end(struct vm_area_struct *vma,
struct zap_details *details)
{
zap_flags_t zap_flags = details ? details->zap_flags : 0;
if (!vma->vm_file) /* hugetlbfs_file_mmap error */
return;
if (zap_flags & ZAP_FLAG_UNMAP) { /* final unmap */
/*
* Unlock and free the vma lock before releasing i_mmap_rwsem.
* When the vma_lock is freed, this makes the vma ineligible
* for pmd sharing. And, i_mmap_rwsem is required to set up
* pmd sharing. This is important as page tables for this
* unmapped range will be asynchrously deleted. If the page
* tables are shared, there will be issues when accessed by
* someone else.
*/
__hugetlb_vma_unlock_write_free(vma);
} else {
hugetlb_vma_unlock_write(vma);
}
if (vma->vm_file)
i_mmap_unlock_write(vma->vm_file->f_mapping);
}
void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct page *ref_page,
zap_flags_t zap_flags)
{
struct mmu_notifier_range range;
struct mmu_gather tlb;
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma->vm_mm,
start, end);
adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end);
mmu_notifier_invalidate_range_start(&range);
tlb_gather_mmu(&tlb, vma->vm_mm);
__unmap_hugepage_range(&tlb, vma, start, end, ref_page, zap_flags);
mmu_notifier_invalidate_range_end(&range);
tlb_finish_mmu(&tlb);
}
/*
* This is called when the original mapper is failing to COW a MAP_PRIVATE
* mapping it owns the reserve page for. The intention is to unmap the page
* from other VMAs and let the children be SIGKILLed if they are faulting the
* same region.
*/
static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
struct page *page, unsigned long address)
{
struct hstate *h = hstate_vma(vma);
struct vm_area_struct *iter_vma;
struct address_space *mapping;
pgoff_t pgoff;
/*
* vm_pgoff is in PAGE_SIZE units, hence the different calculation
* from page cache lookup which is in HPAGE_SIZE units.
*/
address = address & huge_page_mask(h);
pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
vma->vm_pgoff;
mapping = vma->vm_file->f_mapping;
/*
* Take the mapping lock for the duration of the table walk. As
* this mapping should be shared between all the VMAs,
* __unmap_hugepage_range() is called as the lock is already held
*/
i_mmap_lock_write(mapping);
vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) {
/* Do not unmap the current VMA */
if (iter_vma == vma)
continue;
/*
* Shared VMAs have their own reserves and do not affect
* MAP_PRIVATE accounting but it is possible that a shared
* VMA is using the same page so check and skip such VMAs.
*/
if (iter_vma->vm_flags & VM_MAYSHARE)
continue;
/*
* Unmap the page from other VMAs without their own reserves.
* They get marked to be SIGKILLed if they fault in these
* areas. This is because a future no-page fault on this VMA
* could insert a zeroed page instead of the data existing
* from the time of fork. This would look like data corruption
*/
if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER))
unmap_hugepage_range(iter_vma, address,
address + huge_page_size(h), page, 0);
}
i_mmap_unlock_write(mapping);
}
/*
* hugetlb_wp() should be called with page lock of the original hugepage held.
* Called with hugetlb_fault_mutex_table held and pte_page locked so we
* cannot race with other handlers or page migration.
* Keep the pte_same checks anyway to make transition from the mutex easier.
*/
static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, unsigned int flags,
struct folio *pagecache_folio, spinlock_t *ptl,
struct vm_fault *vmf)
{
const bool unshare = flags & FAULT_FLAG_UNSHARE;
pte_t pte = huge_ptep_get(ptep);
struct hstate *h = hstate_vma(vma);
struct folio *old_folio;
struct folio *new_folio;
int outside_reserve = 0;
vm_fault_t ret = 0;
unsigned long haddr = address & huge_page_mask(h);
struct mmu_notifier_range range;
/*
* Never handle CoW for uffd-wp protected pages. It should be only
* handled when the uffd-wp protection is removed.
*
* Note that only the CoW optimization path (in hugetlb_no_page())
* can trigger this, because hugetlb_fault() will always resolve
* uffd-wp bit first.
*/
if (!unshare && huge_pte_uffd_wp(pte))
return 0;
/*
* hugetlb does not support FOLL_FORCE-style write faults that keep the
* PTE mapped R/O such as maybe_mkwrite() would do.
*/
if (WARN_ON_ONCE(!unshare && !(vma->vm_flags & VM_WRITE)))
return VM_FAULT_SIGSEGV;
/* Let's take out MAP_SHARED mappings first. */
if (vma->vm_flags & VM_MAYSHARE) {
set_huge_ptep_writable(vma, haddr, ptep);
return 0;
}
old_folio = page_folio(pte_page(pte));
delayacct_wpcopy_start();
retry_avoidcopy:
/*
* If no-one else is actually using this page, we're the exclusive
* owner and can reuse this page.
*/
if (folio_mapcount(old_folio) == 1 && folio_test_anon(old_folio)) {
if (!PageAnonExclusive(&old_folio->page)) {
folio_move_anon_rmap(old_folio, vma);
SetPageAnonExclusive(&old_folio->page);
}
if (likely(!unshare))
set_huge_ptep_writable(vma, haddr, ptep);
delayacct_wpcopy_end();
return 0;
}
VM_BUG_ON_PAGE(folio_test_anon(old_folio) &&
PageAnonExclusive(&old_folio->page), &old_folio->page);
/*
* If the process that created a MAP_PRIVATE mapping is about to
* perform a COW due to a shared page count, attempt to satisfy
* the allocation without using the existing reserves. The pagecache
* page is used to determine if the reserve at this address was
* consumed or not. If reserves were used, a partial faulted mapping
* at the time of fork() could consume its reserves on COW instead
* of the full address range.
*/
if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
old_folio != pagecache_folio)
outside_reserve = 1;
folio_get(old_folio);
/*
* Drop page table lock as buddy allocator may be called. It will
* be acquired again before returning to the caller, as expected.
*/
spin_unlock(ptl);
new_folio = alloc_hugetlb_folio(vma, haddr, outside_reserve);
if (IS_ERR(new_folio)) {
/*
* If a process owning a MAP_PRIVATE mapping fails to COW,
* it is due to references held by a child and an insufficient
* huge page pool. To guarantee the original mappers
* reliability, unmap the page from child processes. The child
* may get SIGKILLed if it later faults.
*/
if (outside_reserve) {
struct address_space *mapping = vma->vm_file->f_mapping;
pgoff_t idx;
u32 hash;
folio_put(old_folio);
/*
* Drop hugetlb_fault_mutex and vma_lock before
* unmapping. unmapping needs to hold vma_lock
* in write mode. Dropping vma_lock in read mode
* here is OK as COW mappings do not interact with
* PMD sharing.
*
* Reacquire both after unmap operation.
*/
idx = vma_hugecache_offset(h, vma, haddr);
hash = hugetlb_fault_mutex_hash(mapping, idx);
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
unmap_ref_private(mm, vma, &old_folio->page, haddr);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
hugetlb_vma_lock_read(vma);
spin_lock(ptl);
ptep = hugetlb_walk(vma, haddr, huge_page_size(h));
if (likely(ptep &&
pte_same(huge_ptep_get(ptep), pte)))
goto retry_avoidcopy;
/*
* race occurs while re-acquiring page table
* lock, and our job is done.
*/
delayacct_wpcopy_end();
return 0;
}
ret = vmf_error(PTR_ERR(new_folio));
goto out_release_old;
}
/*
* When the original hugepage is shared one, it does not have
* anon_vma prepared.
*/
ret = vmf_anon_prepare(vmf);
if (unlikely(ret))
goto out_release_all;
if (copy_user_large_folio(new_folio, old_folio, address, vma)) {
ret = VM_FAULT_HWPOISON_LARGE;
goto out_release_all;
}
__folio_mark_uptodate(new_folio);
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr,
haddr + huge_page_size(h));
mmu_notifier_invalidate_range_start(&range);
/*
* Retake the page table lock to check for racing updates
* before the page tables are altered
*/
spin_lock(ptl);
ptep = hugetlb_walk(vma, haddr, huge_page_size(h));
if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) {
pte_t newpte = make_huge_pte(vma, &new_folio->page, !unshare);
/* Break COW or unshare */
huge_ptep_clear_flush(vma, haddr, ptep);
hugetlb_remove_rmap(old_folio);
hugetlb_add_new_anon_rmap(new_folio, vma, haddr);
if (huge_pte_uffd_wp(pte))
newpte = huge_pte_mkuffd_wp(newpte);
set_huge_pte_at(mm, haddr, ptep, newpte, huge_page_size(h));
folio_set_hugetlb_migratable(new_folio);
/* Make the old page be freed below */
new_folio = old_folio;
}
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(&range);
out_release_all:
/*
* No restore in case of successful pagetable update (Break COW or
* unshare)
*/
if (new_folio != old_folio)
restore_reserve_on_error(h, vma, haddr, new_folio);
folio_put(new_folio);
out_release_old:
folio_put(old_folio);
spin_lock(ptl); /* Caller expects lock to be held */
delayacct_wpcopy_end();
return ret;
}
/*
* Return whether there is a pagecache page to back given address within VMA.
*/
static bool hugetlbfs_pagecache_present(struct hstate *h,
struct vm_area_struct *vma, unsigned long address)
{
struct address_space *mapping = vma->vm_file->f_mapping;
pgoff_t idx = linear_page_index(vma, address);
struct folio *folio;
folio = filemap_get_folio(mapping, idx);
if (IS_ERR(folio))
return false;
folio_put(folio);
return true;
}
int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping,
pgoff_t idx)
{
struct inode *inode = mapping->host;
struct hstate *h = hstate_inode(inode);
int err;
idx <<= huge_page_order(h);
__folio_set_locked(folio);
err = __filemap_add_folio(mapping, folio, idx, GFP_KERNEL, NULL);
if (unlikely(err)) {
__folio_clear_locked(folio);
return err;
}
folio_clear_hugetlb_restore_reserve(folio);
/*
* mark folio dirty so that it will not be removed from cache/file
* by non-hugetlbfs specific code paths.
*/
folio_mark_dirty(folio);
spin_lock(&inode->i_lock);
inode->i_blocks += blocks_per_huge_page(h);
spin_unlock(&inode->i_lock);
return 0;
}
static inline vm_fault_t hugetlb_handle_userfault(struct vm_fault *vmf,
struct address_space *mapping,
unsigned long reason)
{
u32 hash;
/*
* vma_lock and hugetlb_fault_mutex must be dropped before handling
* userfault. Also mmap_lock could be dropped due to handling
* userfault, any vma operation should be careful from here.
*/
hugetlb_vma_unlock_read(vmf->vma);
hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
return handle_userfault(vmf, reason);
}
/*
* Recheck pte with pgtable lock. Returns true if pte didn't change, or
* false if pte changed or is changing.
*/
static bool hugetlb_pte_stable(struct hstate *h, struct mm_struct *mm,
pte_t *ptep, pte_t old_pte)
{
spinlock_t *ptl;
bool same;
ptl = huge_pte_lock(h, mm, ptep);
same = pte_same(huge_ptep_get(ptep), old_pte);
spin_unlock(ptl);
return same;
}
static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
struct vm_area_struct *vma,
struct address_space *mapping, pgoff_t idx,
unsigned long address, pte_t *ptep,
pte_t old_pte, unsigned int flags,
struct vm_fault *vmf)
{
struct hstate *h = hstate_vma(vma);
vm_fault_t ret = VM_FAULT_SIGBUS;
int anon_rmap = 0;
unsigned long size;
struct folio *folio;
pte_t new_pte;
spinlock_t *ptl;
unsigned long haddr = address & huge_page_mask(h);
bool new_folio, new_pagecache_folio = false;
u32 hash = hugetlb_fault_mutex_hash(mapping, idx);
/*
* Currently, we are forced to kill the process in the event the
* original mapper has unmapped pages from the child due to a failed
* COW/unsharing. Warn that such a situation has occurred as it may not
* be obvious.
*/
if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) {
pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n",
current->pid);
goto out;
}
/*
* Use page lock to guard against racing truncation
* before we get page_table_lock.
*/
new_folio = false;
folio = filemap_lock_hugetlb_folio(h, mapping, idx);
if (IS_ERR(folio)) {
size = i_size_read(mapping->host) >> huge_page_shift(h);
if (idx >= size)
goto out;
/* Check for page in userfault range */
if (userfaultfd_missing(vma)) {
/*
* Since hugetlb_no_page() was examining pte
* without pgtable lock, we need to re-test under
* lock because the pte may not be stable and could
* have changed from under us. Try to detect
* either changed or during-changing ptes and retry
* properly when needed.
*
* Note that userfaultfd is actually fine with
* false positives (e.g. caused by pte changed),
* but not wrong logical events (e.g. caused by
* reading a pte during changing). The latter can
* confuse the userspace, so the strictness is very
* much preferred. E.g., MISSING event should
* never happen on the page after UFFDIO_COPY has
* correctly installed the page and returned.
*/
if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) {
ret = 0;
goto out;
}
return hugetlb_handle_userfault(vmf, mapping,
VM_UFFD_MISSING);
}
folio = alloc_hugetlb_folio(vma, haddr, 0);
if (IS_ERR(folio)) {
/*
* Returning error will result in faulting task being
* sent SIGBUS. The hugetlb fault mutex prevents two
* tasks from racing to fault in the same page which
* could result in false unable to allocate errors.
* Page migration does not take the fault mutex, but
* does a clear then write of pte's under page table
* lock. Page fault code could race with migration,
* notice the clear pte and try to allocate a page
* here. Before returning error, get ptl and make
* sure there really is no pte entry.
*/
if (hugetlb_pte_stable(h, mm, ptep, old_pte))
ret = vmf_error(PTR_ERR(folio));
else
ret = 0;
goto out;
}
clear_huge_page(&folio->page, address, pages_per_huge_page(h));
__folio_mark_uptodate(folio);
new_folio = true;
if (vma->vm_flags & VM_MAYSHARE) {
int err = hugetlb_add_to_page_cache(folio, mapping, idx);
if (err) {
/*
* err can't be -EEXIST which implies someone
* else consumed the reservation since hugetlb
* fault mutex is held when add a hugetlb page
* to the page cache. So it's safe to call
* restore_reserve_on_error() here.
*/
restore_reserve_on_error(h, vma, haddr, folio);
folio_put(folio);
goto out;
}
new_pagecache_folio = true;
} else {
folio_lock(folio);
ret = vmf_anon_prepare(vmf);
if (unlikely(ret))
goto backout_unlocked;
anon_rmap = 1;
}
} else {
/*
* If memory error occurs between mmap() and fault, some process
* don't have hwpoisoned swap entry for errored virtual address.
* So we need to block hugepage fault by PG_hwpoison bit check.
*/
if (unlikely(folio_test_hwpoison(folio))) {
ret = VM_FAULT_HWPOISON_LARGE |
VM_FAULT_SET_HINDEX(hstate_index(h));
goto backout_unlocked;
}
/* Check for page in userfault range. */
if (userfaultfd_minor(vma)) {
folio_unlock(folio);
folio_put(folio);
/* See comment in userfaultfd_missing() block above */
if (!hugetlb_pte_stable(h, mm, ptep, old_pte)) {
ret = 0;
goto out;
}
return hugetlb_handle_userfault(vmf, mapping,
VM_UFFD_MINOR);
}
}
/*
* If we are going to COW a private mapping later, we examine the
* pending reservations for this page now. This will ensure that
* any allocations necessary to record that reservation occur outside
* the spinlock.
*/
if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
if (vma_needs_reservation(h, vma, haddr) < 0) {
ret = VM_FAULT_OOM;
goto backout_unlocked;
}
/* Just decrements count, does not deallocate */
vma_end_reservation(h, vma, haddr);
}
ptl = huge_pte_lock(h, mm, ptep);
ret = 0;
/* If pte changed from under us, retry */
if (!pte_same(huge_ptep_get(ptep), old_pte))
goto backout;
if (anon_rmap)
hugetlb_add_new_anon_rmap(folio, vma, haddr);
else
hugetlb_add_file_rmap(folio);
new_pte = make_huge_pte(vma, &folio->page, ((vma->vm_flags & VM_WRITE)
&& (vma->vm_flags & VM_SHARED)));
/*
* If this pte was previously wr-protected, keep it wr-protected even
* if populated.
*/
if (unlikely(pte_marker_uffd_wp(old_pte)))
new_pte = huge_pte_mkuffd_wp(new_pte);
set_huge_pte_at(mm, haddr, ptep, new_pte, huge_page_size(h));
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* Optimization, do the COW without a second fault */
ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl, vmf);
}
spin_unlock(ptl);
/*
* Only set hugetlb_migratable in newly allocated pages. Existing pages
* found in the pagecache may not have hugetlb_migratable if they have
* been isolated for migration.
*/
if (new_folio)
folio_set_hugetlb_migratable(folio);
folio_unlock(folio);
out:
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
return ret;
backout:
spin_unlock(ptl);
backout_unlocked:
if (new_folio && !new_pagecache_folio)
restore_reserve_on_error(h, vma, haddr, folio);
folio_unlock(folio);
folio_put(folio);
goto out;
}
#ifdef CONFIG_SMP
u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx)
{
unsigned long key[2];
u32 hash;
key[0] = (unsigned long) mapping;
key[1] = idx;
hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0);
return hash & (num_fault_mutexes - 1);
}
#else
/*
* For uniprocessor systems we always use a single mutex, so just
* return 0 and avoid the hashing overhead.
*/
u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx)
{
return 0;
}
#endif
vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
pte_t *ptep, entry;
spinlock_t *ptl;
vm_fault_t ret;
u32 hash;
struct folio *folio = NULL;
struct folio *pagecache_folio = NULL;
struct hstate *h = hstate_vma(vma);
struct address_space *mapping;
int need_wait_lock = 0;
unsigned long haddr = address & huge_page_mask(h);
struct vm_fault vmf = {
.vma = vma,
.address = haddr,
.real_address = address,
.flags = flags,
.pgoff = vma_hugecache_offset(h, vma, haddr),
/* TODO: Track hugetlb faults using vm_fault */
/*
* Some fields may not be initialized, be careful as it may
* be hard to debug if called functions make assumptions
*/
};
/*
* Serialize hugepage allocation and instantiation, so that we don't
* get spurious allocation failures if two CPUs race to instantiate
* the same page in the page cache.
*/
mapping = vma->vm_file->f_mapping;
hash = hugetlb_fault_mutex_hash(mapping, vmf.pgoff);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
/*
* Acquire vma lock before calling huge_pte_alloc and hold
* until finished with ptep. This prevents huge_pmd_unshare from
* being called elsewhere and making the ptep no longer valid.
*/
hugetlb_vma_lock_read(vma);
ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h));
if (!ptep) {
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
return VM_FAULT_OOM;
}
entry = huge_ptep_get(ptep);
if (huge_pte_none_mostly(entry)) {
if (is_pte_marker(entry)) {
pte_marker marker =
pte_marker_get(pte_to_swp_entry(entry));
if (marker & PTE_MARKER_POISONED) {
ret = VM_FAULT_HWPOISON_LARGE;
goto out_mutex;
}
}
/*
* Other PTE markers should be handled the same way as none PTE.
*
* hugetlb_no_page will drop vma lock and hugetlb fault
* mutex internally, which make us return immediately.
*/
return hugetlb_no_page(mm, vma, mapping, vmf.pgoff, address,
ptep, entry, flags, &vmf);
}
ret = 0;
/*
* entry could be a migration/hwpoison entry at this point, so this
* check prevents the kernel from going below assuming that we have
* an active hugepage in pagecache. This goto expects the 2nd page
* fault, and is_hugetlb_entry_(migration|hwpoisoned) check will
* properly handle it.
*/
if (!pte_present(entry)) {
if (unlikely(is_hugetlb_entry_migration(entry))) {
/*
* Release the hugetlb fault lock now, but retain
* the vma lock, because it is needed to guard the
* huge_pte_lockptr() later in
* migration_entry_wait_huge(). The vma lock will
* be released there.
*/
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
migration_entry_wait_huge(vma, ptep);
return 0;
} else if (unlikely(is_hugetlb_entry_hwpoisoned(entry)))
ret = VM_FAULT_HWPOISON_LARGE |
VM_FAULT_SET_HINDEX(hstate_index(h));
goto out_mutex;
}
/*
* If we are going to COW/unshare the mapping later, we examine the
* pending reservations for this page now. This will ensure that any
* allocations necessary to record that reservation occur outside the
* spinlock. Also lookup the pagecache page now as it is used to
* determine if a reservation has been consumed.
*/
if ((flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) &&
!(vma->vm_flags & VM_MAYSHARE) && !huge_pte_write(entry)) {
if (vma_needs_reservation(h, vma, haddr) < 0) {
ret = VM_FAULT_OOM;
goto out_mutex;
}
/* Just decrements count, does not deallocate */
vma_end_reservation(h, vma, haddr);
pagecache_folio = filemap_lock_hugetlb_folio(h, mapping,
vmf.pgoff);
if (IS_ERR(pagecache_folio))
pagecache_folio = NULL;
}
ptl = huge_pte_lock(h, mm, ptep);
/* Check for a racing update before calling hugetlb_wp() */
if (unlikely(!pte_same(entry, huge_ptep_get(ptep))))
goto out_ptl;
/* Handle userfault-wp first, before trying to lock more pages */
if (userfaultfd_wp(vma) && huge_pte_uffd_wp(huge_ptep_get(ptep)) &&
(flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) {
if (!userfaultfd_wp_async(vma)) {
spin_unlock(ptl);
if (pagecache_folio) {
folio_unlock(pagecache_folio);
folio_put(pagecache_folio);
}
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
return handle_userfault(&vmf, VM_UFFD_WP);
}
entry = huge_pte_clear_uffd_wp(entry);
set_huge_pte_at(mm, haddr, ptep, entry,
huge_page_size(hstate_vma(vma)));
/* Fallthrough to CoW */
}
/*
* hugetlb_wp() requires page locks of pte_page(entry) and
* pagecache_folio, so here we need take the former one
* when folio != pagecache_folio or !pagecache_folio.
*/
folio = page_folio(pte_page(entry));
if (folio != pagecache_folio)
if (!folio_trylock(folio)) {
need_wait_lock = 1;
goto out_ptl;
}
folio_get(folio);
if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) {
if (!huge_pte_write(entry)) {
ret = hugetlb_wp(mm, vma, address, ptep, flags,
pagecache_folio, ptl, &vmf);
goto out_put_page;
} else if (likely(flags & FAULT_FLAG_WRITE)) {
entry = huge_pte_mkdirty(entry);
}
}
entry = pte_mkyoung(entry);
if (huge_ptep_set_access_flags(vma, haddr, ptep, entry,
flags & FAULT_FLAG_WRITE))
update_mmu_cache(vma, haddr, ptep);
out_put_page:
if (folio != pagecache_folio)
folio_unlock(folio);
folio_put(folio);
out_ptl:
spin_unlock(ptl);
if (pagecache_folio) {
folio_unlock(pagecache_folio);
folio_put(pagecache_folio);
}
out_mutex:
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
/*
* Generally it's safe to hold refcount during waiting page lock. But
* here we just wait to defer the next page fault to avoid busy loop and
* the page is not used after unlocked before returning from the current
* page fault. So we are safe from accessing freed page, even if we wait
* here without taking refcount.
*/
if (need_wait_lock)
folio_wait_locked(folio);
return ret;
}
#ifdef CONFIG_USERFAULTFD
/*
* Can probably be eliminated, but still used by hugetlb_mfill_atomic_pte().
*/
static struct folio *alloc_hugetlb_folio_vma(struct hstate *h,
struct vm_area_struct *vma, unsigned long address)
{
struct mempolicy *mpol;
nodemask_t *nodemask;
struct folio *folio;
gfp_t gfp_mask;
int node;
gfp_mask = htlb_alloc_mask(h);
node = huge_node(vma, address, gfp_mask, &mpol, &nodemask);
folio = alloc_hugetlb_folio_nodemask(h, node, nodemask, gfp_mask);
mpol_cond_put(mpol);
return folio;
}
/*
* Used by userfaultfd UFFDIO_* ioctls. Based on userfaultfd's mfill_atomic_pte
* with modifications for hugetlb pages.
*/
int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
struct vm_area_struct *dst_vma,
unsigned long dst_addr,
unsigned long src_addr,
uffd_flags_t flags,
struct folio **foliop)
{
struct mm_struct *dst_mm = dst_vma->vm_mm;
bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE);
bool wp_enabled = (flags & MFILL_ATOMIC_WP);
struct hstate *h = hstate_vma(dst_vma);
struct address_space *mapping = dst_vma->vm_file->f_mapping;
pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr);
unsigned long size;
int vm_shared = dst_vma->vm_flags & VM_SHARED;
pte_t _dst_pte;
spinlock_t *ptl;
int ret = -ENOMEM;
struct folio *folio;
int writable;
bool folio_in_pagecache = false;
if (uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) {
ptl = huge_pte_lock(h, dst_mm, dst_pte);
/* Don't overwrite any existing PTEs (even markers) */
if (!huge_pte_none(huge_ptep_get(dst_pte))) {
spin_unlock(ptl);
return -EEXIST;
}
_dst_pte = make_pte_marker(PTE_MARKER_POISONED);
set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte,
huge_page_size(h));
/* No need to invalidate - it was non-present before */
update_mmu_cache(dst_vma, dst_addr, dst_pte);
spin_unlock(ptl);
return 0;
}
if (is_continue) {
ret = -EFAULT;
folio = filemap_lock_hugetlb_folio(h, mapping, idx);
if (IS_ERR(folio))
goto out;
folio_in_pagecache = true;
} else if (!*foliop) {
/* If a folio already exists, then it's UFFDIO_COPY for
* a non-missing case. Return -EEXIST.
*/
if (vm_shared &&
hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) {
ret = -EEXIST;
goto out;
}
folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0);
if (IS_ERR(folio)) {
ret = -ENOMEM;
goto out;
}
ret = copy_folio_from_user(folio, (const void __user *) src_addr,
false);
/* fallback to copy_from_user outside mmap_lock */
if (unlikely(ret)) {
ret = -ENOENT;
/* Free the allocated folio which may have
* consumed a reservation.
*/
restore_reserve_on_error(h, dst_vma, dst_addr, folio);
folio_put(folio);
/* Allocate a temporary folio to hold the copied
* contents.
*/
folio = alloc_hugetlb_folio_vma(h, dst_vma, dst_addr);
if (!folio) {
ret = -ENOMEM;
goto out;
}
*foliop = folio;
/* Set the outparam foliop and return to the caller to
* copy the contents outside the lock. Don't free the
* folio.
*/
goto out;
}
} else {
if (vm_shared &&
hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) {
folio_put(*foliop);
ret = -EEXIST;
*foliop = NULL;
goto out;
}
folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0);
if (IS_ERR(folio)) {
folio_put(*foliop);
ret = -ENOMEM;
*foliop = NULL;
goto out;
}
ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma);
folio_put(*foliop);
*foliop = NULL;
if (ret) {
folio_put(folio);
goto out;
}
}
/*
* The memory barrier inside __folio_mark_uptodate makes sure that
* preceding stores to the page contents become visible before
* the set_pte_at() write.
*/
__folio_mark_uptodate(folio);
/* Add shared, newly allocated pages to the page cache. */
if (vm_shared && !is_continue) {
size = i_size_read(mapping->host) >> huge_page_shift(h);
ret = -EFAULT;
if (idx >= size)
goto out_release_nounlock;
/*
* Serialization between remove_inode_hugepages() and
* hugetlb_add_to_page_cache() below happens through the
* hugetlb_fault_mutex_table that here must be hold by
* the caller.
*/
ret = hugetlb_add_to_page_cache(folio, mapping, idx);
if (ret)
goto out_release_nounlock;
folio_in_pagecache = true;
}
ptl = huge_pte_lock(h, dst_mm, dst_pte);
ret = -EIO;
if (folio_test_hwpoison(folio))
goto out_release_unlock;
/*
* We allow to overwrite a pte marker: consider when both MISSING|WP
* registered, we firstly wr-protect a none pte which has no page cache
* page backing it, then access the page.
*/
ret = -EEXIST;
if (!huge_pte_none_mostly(huge_ptep_get(dst_pte)))
goto out_release_unlock;
if (folio_in_pagecache)
hugetlb_add_file_rmap(folio);
else
hugetlb_add_new_anon_rmap(folio, dst_vma, dst_addr);
/*
* For either: (1) CONTINUE on a non-shared VMA, or (2) UFFDIO_COPY
* with wp flag set, don't set pte write bit.
*/
if (wp_enabled || (is_continue && !vm_shared))
writable = 0;
else
writable = dst_vma->vm_flags & VM_WRITE;
_dst_pte = make_huge_pte(dst_vma, &folio->page, writable);
/*
* Always mark UFFDIO_COPY page dirty; note that this may not be
* extremely important for hugetlbfs for now since swapping is not
* supported, but we should still be clear in that this page cannot be
* thrown away at will, even if write bit not set.
*/
_dst_pte = huge_pte_mkdirty(_dst_pte);
_dst_pte = pte_mkyoung(_dst_pte);
if (wp_enabled)
_dst_pte = huge_pte_mkuffd_wp(_dst_pte);
set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte, huge_page_size(h));
hugetlb_count_add(pages_per_huge_page(h), dst_mm);
/* No need to invalidate - it was non-present before */
update_mmu_cache(dst_vma, dst_addr, dst_pte);
spin_unlock(ptl);
if (!is_continue)
folio_set_hugetlb_migratable(folio);
if (vm_shared || is_continue)
folio_unlock(folio);
ret = 0;
out:
return ret;
out_release_unlock:
spin_unlock(ptl);
if (vm_shared || is_continue)
folio_unlock(folio);
out_release_nounlock:
if (!folio_in_pagecache)
restore_reserve_on_error(h, dst_vma, dst_addr, folio);
folio_put(folio);
goto out;
}
#endif /* CONFIG_USERFAULTFD */
struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma,
unsigned long address, unsigned int flags,
unsigned int *page_mask)
{
struct hstate *h = hstate_vma(vma);
struct mm_struct *mm = vma->vm_mm;
unsigned long haddr = address & huge_page_mask(h);
struct page *page = NULL;
spinlock_t *ptl;
pte_t *pte, entry;
int ret;
hugetlb_vma_lock_read(vma);
pte = hugetlb_walk(vma, haddr, huge_page_size(h));
if (!pte)
goto out_unlock;
ptl = huge_pte_lock(h, mm, pte);
entry = huge_ptep_get(pte);
if (pte_present(entry)) {
page = pte_page(entry);
if (!huge_pte_write(entry)) {
if (flags & FOLL_WRITE) {
page = NULL;
goto out;
}
if (gup_must_unshare(vma, flags, page)) {
/* Tell the caller to do unsharing */
page = ERR_PTR(-EMLINK);
goto out;
}
}
page = nth_page(page, ((address & ~huge_page_mask(h)) >> PAGE_SHIFT));
/*
* Note that page may be a sub-page, and with vmemmap
* optimizations the page struct may be read only.
* try_grab_page() will increase the ref count on the
* head page, so this will be OK.
*
* try_grab_page() should always be able to get the page here,
* because we hold the ptl lock and have verified pte_present().
*/
ret = try_grab_page(page, flags);
if (WARN_ON_ONCE(ret)) {
page = ERR_PTR(ret);
goto out;
}
*page_mask = (1U << huge_page_order(h)) - 1;
}
out:
spin_unlock(ptl);
out_unlock:
hugetlb_vma_unlock_read(vma);
/*
* Fixup retval for dump requests: if pagecache doesn't exist,
* don't try to allocate a new page but just skip it.
*/
if (!page && (flags & FOLL_DUMP) &&
!hugetlbfs_pagecache_present(h, vma, address))
page = ERR_PTR(-EFAULT);
return page;
}
long hugetlb_change_protection(struct vm_area_struct *vma,
unsigned long address, unsigned long end,
pgprot_t newprot, unsigned long cp_flags)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long start = address;
pte_t *ptep;
pte_t pte;
struct hstate *h = hstate_vma(vma);
long pages = 0, psize = huge_page_size(h);
bool shared_pmd = false;
struct mmu_notifier_range range;
unsigned long last_addr_mask;
bool uffd_wp = cp_flags & MM_CP_UFFD_WP;
bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE;
/*
* In the case of shared PMDs, the area to flush could be beyond
* start/end. Set range.start/range.end to cover the maximum possible
* range if PMD sharing is possible.
*/
mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA,
0, mm, start, end);
adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end);
BUG_ON(address >= end);
flush_cache_range(vma, range.start, range.end);
mmu_notifier_invalidate_range_start(&range);
hugetlb_vma_lock_write(vma);
i_mmap_lock_write(vma->vm_file->f_mapping);
last_addr_mask = hugetlb_mask_last_page(h);
for (; address < end; address += psize) {
spinlock_t *ptl;
ptep = hugetlb_walk(vma, address, psize);
if (!ptep) {
if (!uffd_wp) {
address |= last_addr_mask;
continue;
}
/*
* Userfaultfd wr-protect requires pgtable
* pre-allocations to install pte markers.
*/
ptep = huge_pte_alloc(mm, vma, address, psize);
if (!ptep) {
pages = -ENOMEM;
break;
}
}
ptl = huge_pte_lock(h, mm, ptep);
if (huge_pmd_unshare(mm, vma, address, ptep)) {
/*
* When uffd-wp is enabled on the vma, unshare
* shouldn't happen at all. Warn about it if it
* happened due to some reason.
*/
WARN_ON_ONCE(uffd_wp || uffd_wp_resolve);
pages++;
spin_unlock(ptl);
shared_pmd = true;
address |= last_addr_mask;
continue;
}
pte = huge_ptep_get(ptep);
if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) {
/* Nothing to do. */
} else if (unlikely(is_hugetlb_entry_migration(pte))) {
swp_entry_t entry = pte_to_swp_entry(pte);
struct page *page = pfn_swap_entry_to_page(entry);
pte_t newpte = pte;
if (is_writable_migration_entry(entry)) {
if (PageAnon(page))
entry = make_readable_exclusive_migration_entry(
swp_offset(entry));
else
entry = make_readable_migration_entry(
swp_offset(entry));
newpte = swp_entry_to_pte(entry);
pages++;
}
if (uffd_wp)
newpte = pte_swp_mkuffd_wp(newpte);
else if (uffd_wp_resolve)
newpte = pte_swp_clear_uffd_wp(newpte);
if (!pte_same(pte, newpte))
set_huge_pte_at(mm, address, ptep, newpte, psize);
} else if (unlikely(is_pte_marker(pte))) {
/* No other markers apply for now. */
WARN_ON_ONCE(!pte_marker_uffd_wp(pte));
if (uffd_wp_resolve)
/* Safe to modify directly (non-present->none). */
huge_pte_clear(mm, address, ptep, psize);
} else if (!huge_pte_none(pte)) {
pte_t old_pte;
unsigned int shift = huge_page_shift(hstate_vma(vma));
old_pte = huge_ptep_modify_prot_start(vma, address, ptep);
pte = huge_pte_modify(old_pte, newprot);
pte = arch_make_huge_pte(pte, shift, vma->vm_flags);
if (uffd_wp)
pte = huge_pte_mkuffd_wp(pte);
else if (uffd_wp_resolve)
pte = huge_pte_clear_uffd_wp(pte);
huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte);
pages++;
} else {
/* None pte */
if (unlikely(uffd_wp))
/* Safe to modify directly (none->non-present). */
set_huge_pte_at(mm, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP),
psize);
}
spin_unlock(ptl);
}
/*
* Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare
* may have cleared our pud entry and done put_page on the page table:
* once we release i_mmap_rwsem, another task can do the final put_page
* and that page table be reused and filled with junk. If we actually
* did unshare a page of pmds, flush the range corresponding to the pud.
*/
if (shared_pmd)
flush_hugetlb_tlb_range(vma, range.start, range.end);
else
flush_hugetlb_tlb_range(vma, start, end);
/*
* No need to call mmu_notifier_arch_invalidate_secondary_tlbs() we are
* downgrading page table protection not changing it to point to a new
* page.
*
* See Documentation/mm/mmu_notifier.rst
*/
i_mmap_unlock_write(vma->vm_file->f_mapping);
hugetlb_vma_unlock_write(vma);
mmu_notifier_invalidate_range_end(&range);
return pages > 0 ? (pages << h->order) : pages;
}
/* Return true if reservation was successful, false otherwise. */
bool hugetlb_reserve_pages(struct inode *inode,
long from, long to,
struct vm_area_struct *vma,
vm_flags_t vm_flags)
{
long chg = -1, add = -1;
struct hstate *h = hstate_inode(inode);
struct hugepage_subpool *spool = subpool_inode(inode);
struct resv_map *resv_map;
struct hugetlb_cgroup *h_cg = NULL;
long gbl_reserve, regions_needed = 0;
/* This should never happen */
if (from > to) {
VM_WARN(1, "%s called with a negative range\n", __func__);
return false;
}
/*
* vma specific semaphore used for pmd sharing and fault/truncation
* synchronization
*/
hugetlb_vma_lock_alloc(vma);
/*
* Only apply hugepage reservation if asked. At fault time, an
* attempt will be made for VM_NORESERVE to allocate a page
* without using reserves
*/
if (vm_flags & VM_NORESERVE)
return true;
/*
* Shared mappings base their reservation on the number of pages that
* are already allocated on behalf of the file. Private mappings need
* to reserve the full area even if read-only as mprotect() may be
* called to make the mapping read-write. Assume !vma is a shm mapping
*/
if (!vma || vma->vm_flags & VM_MAYSHARE) {
/*
* resv_map can not be NULL as hugetlb_reserve_pages is only
* called for inodes for which resv_maps were created (see
* hugetlbfs_get_inode).
*/
resv_map = inode_resv_map(inode);
chg = region_chg(resv_map, from, to, ®ions_needed);
} else {
/* Private mapping. */
resv_map = resv_map_alloc();
if (!resv_map)
goto out_err;
chg = to - from;
set_vma_resv_map(vma, resv_map);
set_vma_resv_flags(vma, HPAGE_RESV_OWNER);
}
if (chg < 0)
goto out_err;
if (hugetlb_cgroup_charge_cgroup_rsvd(hstate_index(h),
chg * pages_per_huge_page(h), &h_cg) < 0)
goto out_err;
if (vma && !(vma->vm_flags & VM_MAYSHARE) && h_cg) {
/* For private mappings, the hugetlb_cgroup uncharge info hangs
* of the resv_map.
*/
resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, h_cg, h);
}
/*
* There must be enough pages in the subpool for the mapping. If
* the subpool has a minimum size, there may be some global
* reservations already in place (gbl_reserve).
*/
gbl_reserve = hugepage_subpool_get_pages(spool, chg);
if (gbl_reserve < 0)
goto out_uncharge_cgroup;
/*
* Check enough hugepages are available for the reservation.
* Hand the pages back to the subpool if there are not
*/
if (hugetlb_acct_memory(h, gbl_reserve) < 0)
goto out_put_pages;
/*
* Account for the reservations made. Shared mappings record regions
* that have reservations as they are shared by multiple VMAs.
* When the last VMA disappears, the region map says how much
* the reservation was and the page cache tells how much of
* the reservation was consumed. Private mappings are per-VMA and
* only the consumed reservations are tracked. When the VMA
* disappears, the original reservation is the VMA size and the
* consumed reservations are stored in the map. Hence, nothing
* else has to be done for private mappings here
*/
if (!vma || vma->vm_flags & VM_MAYSHARE) {
add = region_add(resv_map, from, to, regions_needed, h, h_cg);
if (unlikely(add < 0)) {
hugetlb_acct_memory(h, -gbl_reserve);
goto out_put_pages;
} else if (unlikely(chg > add)) {
/*
* pages in this range were added to the reserve
* map between region_chg and region_add. This
* indicates a race with alloc_hugetlb_folio. Adjust
* the subpool and reserve counts modified above
* based on the difference.
*/
long rsv_adjust;
/*
* hugetlb_cgroup_uncharge_cgroup_rsvd() will put the
* reference to h_cg->css. See comment below for detail.
*/
hugetlb_cgroup_uncharge_cgroup_rsvd(
hstate_index(h),
(chg - add) * pages_per_huge_page(h), h_cg);
rsv_adjust = hugepage_subpool_put_pages(spool,
chg - add);
hugetlb_acct_memory(h, -rsv_adjust);
} else if (h_cg) {
/*
* The file_regions will hold their own reference to
* h_cg->css. So we should release the reference held
* via hugetlb_cgroup_charge_cgroup_rsvd() when we are
* done.
*/
hugetlb_cgroup_put_rsvd_cgroup(h_cg);
}
}
return true;
out_put_pages:
/* put back original number of pages, chg */
(void)hugepage_subpool_put_pages(spool, chg);
out_uncharge_cgroup:
hugetlb_cgroup_uncharge_cgroup_rsvd(hstate_index(h),
chg * pages_per_huge_page(h), h_cg);
out_err:
hugetlb_vma_lock_free(vma);
if (!vma || vma->vm_flags & VM_MAYSHARE)
/* Only call region_abort if the region_chg succeeded but the
* region_add failed or didn't run.
*/
if (chg >= 0 && add < 0)
region_abort(resv_map, from, to, regions_needed);
if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
kref_put(&resv_map->refs, resv_map_release);
set_vma_resv_map(vma, NULL);
}
return false;
}
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
long freed)
{
struct hstate *h = hstate_inode(inode);
struct resv_map *resv_map = inode_resv_map(inode);
long chg = 0;
struct hugepage_subpool *spool = subpool_inode(inode);
long gbl_reserve;
/*
* Since this routine can be called in the evict inode path for all
* hugetlbfs inodes, resv_map could be NULL.
*/
if (resv_map) {
chg = region_del(resv_map, start, end);
/*
* region_del() can fail in the rare case where a region
* must be split and another region descriptor can not be
* allocated. If end == LONG_MAX, it will not fail.
*/
if (chg < 0)
return chg;
}
spin_lock(&inode->i_lock);
inode->i_blocks -= (blocks_per_huge_page(h) * freed);
spin_unlock(&inode->i_lock);
/*
* If the subpool has a minimum size, the number of global
* reservations to be released may be adjusted.
*
* Note that !resv_map implies freed == 0. So (chg - freed)
* won't go negative.
*/
gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed));
hugetlb_acct_memory(h, -gbl_reserve);
return 0;
}
#ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
static unsigned long page_table_shareable(struct vm_area_struct *svma,
struct vm_area_struct *vma,
unsigned long addr, pgoff_t idx)
{
unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) +
svma->vm_start;
unsigned long sbase = saddr & PUD_MASK;
unsigned long s_end = sbase + PUD_SIZE;
/* Allow segments to share if only one is marked locked */
unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED_MASK;
unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED_MASK;
/*
* match the virtual addresses, permission and the alignment of the
* page table page.
*
* Also, vma_lock (vm_private_data) is required for sharing.
*/
if (pmd_index(addr) != pmd_index(saddr) ||
vm_flags != svm_flags ||
!range_in_vma(svma, sbase, s_end) ||
!svma->vm_private_data)
return 0;
return saddr;
}
bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr)
{
unsigned long start = addr & PUD_MASK;
unsigned long end = start + PUD_SIZE;
#ifdef CONFIG_USERFAULTFD
if (uffd_disable_huge_pmd_share(vma))
return false;
#endif
/*
* check on proper vm_flags and page table alignment
*/
if (!(vma->vm_flags & VM_MAYSHARE))
return false;
if (!vma->vm_private_data) /* vma lock required for sharing */
return false;
if (!range_in_vma(vma, start, end))
return false;
return true;
}
/*
* Determine if start,end range within vma could be mapped by shared pmd.
* If yes, adjust start and end to cover range associated with possible
* shared pmd mappings.
*/
void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma,
unsigned long *start, unsigned long *end)
{
unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE),
v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE);
/*
* vma needs to span at least one aligned PUD size, and the range
* must be at least partially within in.
*/
if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) ||
(*end <= v_start) || (*start >= v_end))
return;
/* Extend the range to be PUD aligned for a worst case scenario */
if (*start > v_start)
*start = ALIGN_DOWN(*start, PUD_SIZE);
if (*end < v_end)
*end = ALIGN(*end, PUD_SIZE);
}
/*
* Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc()
* and returns the corresponding pte. While this is not necessary for the
* !shared pmd case because we can allocate the pmd later as well, it makes the
* code much cleaner. pmd allocation is essential for the shared case because
* pud has to be populated inside the same i_mmap_rwsem section - otherwise
* racing tasks could either miss the sharing (see huge_pte_offset) or select a
* bad pmd for sharing.
*/
pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pud_t *pud)
{
struct address_space *mapping = vma->vm_file->f_mapping;
pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
vma->vm_pgoff;
struct vm_area_struct *svma;
unsigned long saddr;
pte_t *spte = NULL;
pte_t *pte;
i_mmap_lock_read(mapping);
vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) {
if (svma == vma)
continue;
saddr = page_table_shareable(svma, vma, addr, idx);
if (saddr) {
spte = hugetlb_walk(svma, saddr,
vma_mmu_pagesize(svma));
if (spte) {
get_page(virt_to_page(spte));
break;
}
}
}
if (!spte)
goto out;
spin_lock(&mm->page_table_lock);
if (pud_none(*pud)) {
pud_populate(mm, pud,
(pmd_t *)((unsigned long)spte & PAGE_MASK));
mm_inc_nr_pmds(mm);
} else {
put_page(virt_to_page(spte));
}
spin_unlock(&mm->page_table_lock);
out:
pte = (pte_t *)pmd_alloc(mm, pud, addr);
i_mmap_unlock_read(mapping);
return pte;
}
/*
* unmap huge page backed by shared pte.
*
* Hugetlb pte page is ref counted at the time of mapping. If pte is shared
* indicated by page_count > 1, unmap is achieved by clearing pud and
* decrementing the ref count. If count == 1, the pte page is not shared.
*
* Called with page table lock held.
*
* returns: 1 successfully unmapped a shared pte page
* 0 the underlying pte page is not shared, or it is the last user
*/
int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
pgd_t *pgd = pgd_offset(mm, addr);
p4d_t *p4d = p4d_offset(pgd, addr);
pud_t *pud = pud_offset(p4d, addr);
i_mmap_assert_write_locked(vma->vm_file->f_mapping);
hugetlb_vma_assert_locked(vma);
BUG_ON(page_count(virt_to_page(ptep)) == 0);
if (page_count(virt_to_page(ptep)) == 1)
return 0;
pud_clear(pud);
put_page(virt_to_page(ptep));
mm_dec_nr_pmds(mm);
return 1;
}
#else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pud_t *pud)
{
return NULL;
}
int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
return 0;
}
void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma,
unsigned long *start, unsigned long *end)
{
}
bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr)
{
return false;
}
#endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
#ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB
pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, unsigned long sz)
{
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pte_t *pte = NULL;
pgd = pgd_offset(mm, addr);
p4d = p4d_alloc(mm, pgd, addr);
if (!p4d)
return NULL;
pud = pud_alloc(mm, p4d, addr);
if (pud) {
if (sz == PUD_SIZE) {
pte = (pte_t *)pud;
} else {
BUG_ON(sz != PMD_SIZE);
if (want_pmd_share(vma, addr) && pud_none(*pud))
pte = huge_pmd_share(mm, vma, addr, pud);
else
pte = (pte_t *)pmd_alloc(mm, pud, addr);
}
}
if (pte) {
pte_t pteval = ptep_get_lockless(pte);
BUG_ON(pte_present(pteval) && !pte_huge(pteval));
}
return pte;
}
/*
* huge_pte_offset() - Walk the page table to resolve the hugepage
* entry at address @addr
*
* Return: Pointer to page table entry (PUD or PMD) for
* address @addr, or NULL if a !p*d_present() entry is encountered and the
* size @sz doesn't match the hugepage size at this level of the page
* table.
*/
pte_t *huge_pte_offset(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pgd = pgd_offset(mm, addr);
if (!pgd_present(*pgd))
return NULL;
p4d = p4d_offset(pgd, addr);
if (!p4d_present(*p4d))
return NULL;
pud = pud_offset(p4d, addr);
if (sz == PUD_SIZE)
/* must be pud huge, non-present or none */
return (pte_t *)pud;
if (!pud_present(*pud))
return NULL;
/* must have a valid entry and size to go further */
pmd = pmd_offset(pud, addr);
/* must be pmd huge, non-present or none */
return (pte_t *)pmd;
}
/*
* Return a mask that can be used to update an address to the last huge
* page in a page table page mapping size. Used to skip non-present
* page table entries when linearly scanning address ranges. Architectures
* with unique huge page to page table relationships can define their own
* version of this routine.
*/
unsigned long hugetlb_mask_last_page(struct hstate *h)
{
unsigned long hp_size = huge_page_size(h);
if (hp_size == PUD_SIZE)
return P4D_SIZE - PUD_SIZE;
else if (hp_size == PMD_SIZE)
return PUD_SIZE - PMD_SIZE;
else
return 0UL;
}
#else
/* See description above. Architectures can provide their own version. */
__weak unsigned long hugetlb_mask_last_page(struct hstate *h)
{
#ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
if (huge_page_size(h) == PMD_SIZE)
return PUD_SIZE - PMD_SIZE;
#endif
return 0UL;
}
#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
/*
* These functions are overwritable if your architecture needs its own
* behavior.
*/
bool isolate_hugetlb(struct folio *folio, struct list_head *list)
{
bool ret = true;
spin_lock_irq(&hugetlb_lock);
if (!folio_test_hugetlb(folio) ||
!folio_test_hugetlb_migratable(folio) ||
!folio_try_get(folio)) {
ret = false;
goto unlock;
}
folio_clear_hugetlb_migratable(folio);
list_move_tail(&folio->lru, list);
unlock:
spin_unlock_irq(&hugetlb_lock);
return ret;
}
int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison)
{
int ret = 0;
*hugetlb = false;
spin_lock_irq(&hugetlb_lock);
if (folio_test_hugetlb(folio)) {
*hugetlb = true;
if (folio_test_hugetlb_freed(folio))
ret = 0;
else if (folio_test_hugetlb_migratable(folio) || unpoison)
ret = folio_try_get(folio);
else
ret = -EBUSY;
}
spin_unlock_irq(&hugetlb_lock);
return ret;
}
int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
int ret;
spin_lock_irq(&hugetlb_lock);
ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared);
spin_unlock_irq(&hugetlb_lock);
return ret;
}
void folio_putback_active_hugetlb(struct folio *folio)
{
spin_lock_irq(&hugetlb_lock);
folio_set_hugetlb_migratable(folio);
list_move_tail(&folio->lru, &(folio_hstate(folio))->hugepage_activelist);
spin_unlock_irq(&hugetlb_lock);
folio_put(folio);
}
void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason)
{
struct hstate *h = folio_hstate(old_folio);
hugetlb_cgroup_migrate(old_folio, new_folio);
set_page_owner_migrate_reason(&new_folio->page, reason);
/*
* transfer temporary state of the new hugetlb folio. This is
* reverse to other transitions because the newpage is going to
* be final while the old one will be freed so it takes over
* the temporary status.
*
* Also note that we have to transfer the per-node surplus state
* here as well otherwise the global surplus count will not match
* the per-node's.
*/
if (folio_test_hugetlb_temporary(new_folio)) {
int old_nid = folio_nid(old_folio);
int new_nid = folio_nid(new_folio);
folio_set_hugetlb_temporary(old_folio);
folio_clear_hugetlb_temporary(new_folio);
/*
* There is no need to transfer the per-node surplus state
* when we do not cross the node.
*/
if (new_nid == old_nid)
return;
spin_lock_irq(&hugetlb_lock);
if (h->surplus_huge_pages_node[old_nid]) {
h->surplus_huge_pages_node[old_nid]--;
h->surplus_huge_pages_node[new_nid]++;
}
spin_unlock_irq(&hugetlb_lock);
}
}
static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
unsigned long start,
unsigned long end)
{
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
struct mm_struct *mm = vma->vm_mm;
struct mmu_notifier_range range;
unsigned long address;
spinlock_t *ptl;
pte_t *ptep;
if (!(vma->vm_flags & VM_MAYSHARE))
return;
if (start >= end)
return;
flush_cache_range(vma, start, end);
/*
* No need to call adjust_range_if_pmd_sharing_possible(), because
* we have already done the PUD_SIZE alignment.
*/
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm,
start, end);
mmu_notifier_invalidate_range_start(&range);
hugetlb_vma_lock_write(vma);
i_mmap_lock_write(vma->vm_file->f_mapping);
for (address = start; address < end; address += PUD_SIZE) {
ptep = hugetlb_walk(vma, address, sz);
if (!ptep)
continue;
ptl = huge_pte_lock(h, mm, ptep);
huge_pmd_unshare(mm, vma, address, ptep);
spin_unlock(ptl);
}
flush_hugetlb_tlb_range(vma, start, end);
i_mmap_unlock_write(vma->vm_file->f_mapping);
hugetlb_vma_unlock_write(vma);
/*
* No need to call mmu_notifier_arch_invalidate_secondary_tlbs(), see
* Documentation/mm/mmu_notifier.rst.
*/
mmu_notifier_invalidate_range_end(&range);
}
/*
* This function will unconditionally remove all the shared pmd pgtable entries
* within the specific vma for a hugetlbfs memory range.
*/
void hugetlb_unshare_all_pmds(struct vm_area_struct *vma)
{
hugetlb_unshare_pmds(vma, ALIGN(vma->vm_start, PUD_SIZE),
ALIGN_DOWN(vma->vm_end, PUD_SIZE));
}
#ifdef CONFIG_CMA
static bool cma_reserve_called __initdata;
static int __init cmdline_parse_hugetlb_cma(char *p)
{
int nid, count = 0;
unsigned long tmp;
char *s = p;
while (*s) {
if (sscanf(s, "%lu%n", &tmp, &count) != 1)
break;
if (s[count] == ':') {
if (tmp >= MAX_NUMNODES)
break;
nid = array_index_nospec(tmp, MAX_NUMNODES);
s += count + 1;
tmp = memparse(s, &s);
hugetlb_cma_size_in_node[nid] = tmp;
hugetlb_cma_size += tmp;
/*
* Skip the separator if have one, otherwise
* break the parsing.
*/
if (*s == ',')
s++;
else
break;
} else {
hugetlb_cma_size = memparse(p, &p);
break;
}
}
return 0;
}
early_param("hugetlb_cma", cmdline_parse_hugetlb_cma);
void __init hugetlb_cma_reserve(int order)
{
unsigned long size, reserved, per_node;
bool node_specific_cma_alloc = false;
int nid;
/*
* HugeTLB CMA reservation is required for gigantic
* huge pages which could not be allocated via the
* page allocator. Just warn if there is any change
* breaking this assumption.
*/
VM_WARN_ON(order <= MAX_PAGE_ORDER);
cma_reserve_called = true;
if (!hugetlb_cma_size)
return;
for (nid = 0; nid < MAX_NUMNODES; nid++) {
if (hugetlb_cma_size_in_node[nid] == 0)
continue;
if (!node_online(nid)) {
pr_warn("hugetlb_cma: invalid node %d specified\n", nid);
hugetlb_cma_size -= hugetlb_cma_size_in_node[nid];
hugetlb_cma_size_in_node[nid] = 0;
continue;
}
if (hugetlb_cma_size_in_node[nid] < (PAGE_SIZE << order)) {
pr_warn("hugetlb_cma: cma area of node %d should be at least %lu MiB\n",
nid, (PAGE_SIZE << order) / SZ_1M);
hugetlb_cma_size -= hugetlb_cma_size_in_node[nid];
hugetlb_cma_size_in_node[nid] = 0;
} else {
node_specific_cma_alloc = true;
}
}
/* Validate the CMA size again in case some invalid nodes specified. */
if (!hugetlb_cma_size)
return;
if (hugetlb_cma_size < (PAGE_SIZE << order)) {
pr_warn("hugetlb_cma: cma area should be at least %lu MiB\n",
(PAGE_SIZE << order) / SZ_1M);
hugetlb_cma_size = 0;
return;
}
if (!node_specific_cma_alloc) {
/*
* If 3 GB area is requested on a machine with 4 numa nodes,
* let's allocate 1 GB on first three nodes and ignore the last one.
*/
per_node = DIV_ROUND_UP(hugetlb_cma_size, nr_online_nodes);
pr_info("hugetlb_cma: reserve %lu MiB, up to %lu MiB per node\n",
hugetlb_cma_size / SZ_1M, per_node / SZ_1M);
}
reserved = 0;
for_each_online_node(nid) {
int res;
char name[CMA_MAX_NAME];
if (node_specific_cma_alloc) {
if (hugetlb_cma_size_in_node[nid] == 0)
continue;
size = hugetlb_cma_size_in_node[nid];
} else {
size = min(per_node, hugetlb_cma_size - reserved);
}
size = round_up(size, PAGE_SIZE << order);
snprintf(name, sizeof(name), "hugetlb%d", nid);
/*
* Note that 'order per bit' is based on smallest size that
* may be returned to CMA allocator in the case of
* huge page demotion.
*/
res = cma_declare_contiguous_nid(0, size, 0,
PAGE_SIZE << HUGETLB_PAGE_ORDER,
0, false, name,
&hugetlb_cma[nid], nid);
if (res) {
pr_warn("hugetlb_cma: reservation failed: err %d, node %d",
res, nid);
continue;
}
reserved += size;
pr_info("hugetlb_cma: reserved %lu MiB on node %d\n",
size / SZ_1M, nid);
if (reserved >= hugetlb_cma_size)
break;
}
if (!reserved)
/*
* hugetlb_cma_size is used to determine if allocations from
* cma are possible. Set to zero if no cma regions are set up.
*/
hugetlb_cma_size = 0;
}
static void __init hugetlb_cma_check(void)
{
if (!hugetlb_cma_size || cma_reserve_called)
return;
pr_warn("hugetlb_cma: the option isn't supported by current arch\n");
}
#endif /* CONFIG_CMA */
|