summaryrefslogtreecommitdiff
path: root/include/linux/mm.h
blob: cc154454675ad79b7de1b816e7df25e4211fb7e0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
#ifndef _LINUX_MM_H
#define _LINUX_MM_H

#include <linux/errno.h>

#ifdef __KERNEL__

#include <linux/mmdebug.h>
#include <linux/gfp.h>
#include <linux/bug.h>
#include <linux/list.h>
#include <linux/mmzone.h>
#include <linux/rbtree.h>
#include <linux/atomic.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
#include <linux/range.h>
#include <linux/pfn.h>
#include <linux/percpu-refcount.h>
#include <linux/bit_spinlock.h>
#include <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
#include <linux/err.h>
#include <linux/page_ref.h>

struct mempolicy;
struct anon_vma;
struct anon_vma_chain;
struct file_ra_state;
struct user_struct;
struct writeback_control;
struct bdi_writeback;

#ifndef CONFIG_NEED_MULTIPLE_NODES	/* Don't use mapnrs, do it properly */
extern unsigned long max_mapnr;

static inline void set_max_mapnr(unsigned long limit)
{
	max_mapnr = limit;
}
#else
static inline void set_max_mapnr(unsigned long limit) { }
#endif

extern unsigned long totalram_pages;
extern void * high_memory;
extern int page_cluster;

#ifdef CONFIG_SYSCTL
extern int sysctl_legacy_va_layout;
#else
#define sysctl_legacy_va_layout 0
#endif

#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
extern const int mmap_rnd_bits_min;
extern const int mmap_rnd_bits_max;
extern int mmap_rnd_bits __read_mostly;
#endif
#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
extern const int mmap_rnd_compat_bits_min;
extern const int mmap_rnd_compat_bits_max;
extern int mmap_rnd_compat_bits __read_mostly;
#endif

#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>

#ifndef __pa_symbol
#define __pa_symbol(x)  __pa(RELOC_HIDE((unsigned long)(x), 0))
#endif

#ifndef page_to_virt
#define page_to_virt(x)	__va(PFN_PHYS(page_to_pfn(x)))
#endif

/*
 * To prevent common memory management code establishing
 * a zero page mapping on a read fault.
 * This macro should be defined within <asm/pgtable.h>.
 * s390 does this to prevent multiplexing of hardware bits
 * related to the physical page in case of virtualization.
 */
#ifndef mm_forbids_zeropage
#define mm_forbids_zeropage(X)	(0)
#endif

/*
 * Default maximum number of active map areas, this limits the number of vmas
 * per mm struct. Users can overwrite this number by sysctl but there is a
 * problem.
 *
 * When a program's coredump is generated as ELF format, a section is created
 * per a vma. In ELF, the number of sections is represented in unsigned short.
 * This means the number of sections should be smaller than 65535 at coredump.
 * Because the kernel adds some informative sections to a image of program at
 * generating coredump, we need some margin. The number of extra sections is
 * 1-3 now and depends on arch. We use "5" as safe margin, here.
 *
 * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
 * not a hard limit any more. Although some userspace tools can be surprised by
 * that.
 */
#define MAPCOUNT_ELF_CORE_MARGIN	(5)
#define DEFAULT_MAX_MAP_COUNT	(USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)

extern int sysctl_max_map_count;

extern unsigned long sysctl_user_reserve_kbytes;
extern unsigned long sysctl_admin_reserve_kbytes;

extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
extern unsigned long sysctl_overcommit_kbytes;

extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *,
				    size_t *, loff_t *);
extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
				    size_t *, loff_t *);

#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))

/* to align the pointer to the (next) page boundary */
#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)

/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
#define PAGE_ALIGNED(addr)	IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)

/*
 * Linux kernel virtual memory manager primitives.
 * The idea being to have a "virtual" mm in the same way
 * we have a virtual fs - giving a cleaner interface to the
 * mm details, and allowing different kinds of memory mappings
 * (from shared memory to executable loading to arbitrary
 * mmap() functions).
 */

extern struct kmem_cache *vm_area_cachep;

#ifndef CONFIG_MMU
extern struct rb_root nommu_region_tree;
extern struct rw_semaphore nommu_region_sem;

extern unsigned int kobjsize(const void *objp);
#endif

/*
 * vm_flags in vm_area_struct, see mm_types.h.
 * When changing, update also include/trace/events/mmflags.h
 */
#define VM_NONE		0x00000000

#define VM_READ		0x00000001	/* currently active flags */
#define VM_WRITE	0x00000002
#define VM_EXEC		0x00000004
#define VM_SHARED	0x00000008

/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
#define VM_MAYREAD	0x00000010	/* limits for mprotect() etc */
#define VM_MAYWRITE	0x00000020
#define VM_MAYEXEC	0x00000040
#define VM_MAYSHARE	0x00000080

#define VM_GROWSDOWN	0x00000100	/* general info on the segment */
#define VM_UFFD_MISSING	0x00000200	/* missing pages tracking */
#define VM_PFNMAP	0x00000400	/* Page-ranges managed without "struct page", just pure PFN */
#define VM_DENYWRITE	0x00000800	/* ETXTBSY on write attempts.. */
#define VM_UFFD_WP	0x00001000	/* wrprotect pages tracking */

#define VM_LOCKED	0x00002000
#define VM_IO           0x00004000	/* Memory mapped I/O or similar */

					/* Used by sys_madvise() */
#define VM_SEQ_READ	0x00008000	/* App will access data sequentially */
#define VM_RAND_READ	0x00010000	/* App will not benefit from clustered reads */

#define VM_DONTCOPY	0x00020000      /* Do not copy this vma on fork */
#define VM_DONTEXPAND	0x00040000	/* Cannot expand with mremap() */
#define VM_LOCKONFAULT	0x00080000	/* Lock the pages covered when they are faulted in */
#define VM_ACCOUNT	0x00100000	/* Is a VM accounted object */
#define VM_NORESERVE	0x00200000	/* should the VM suppress accounting */
#define VM_HUGETLB	0x00400000	/* Huge TLB Page VM */
#define VM_ARCH_1	0x01000000	/* Architecture-specific flag */
#define VM_ARCH_2	0x02000000
#define VM_DONTDUMP	0x04000000	/* Do not include in the core dump */

#ifdef CONFIG_MEM_SOFT_DIRTY
# define VM_SOFTDIRTY	0x08000000	/* Not soft dirty clean area */
#else
# define VM_SOFTDIRTY	0
#endif

#define VM_MIXEDMAP	0x10000000	/* Can contain "struct page" and pure PFN pages */
#define VM_HUGEPAGE	0x20000000	/* MADV_HUGEPAGE marked this vma */
#define VM_NOHUGEPAGE	0x40000000	/* MADV_NOHUGEPAGE marked this vma */
#define VM_MERGEABLE	0x80000000	/* KSM may merge identical pages */

#ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS
#define VM_HIGH_ARCH_BIT_0	32	/* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_BIT_1	33	/* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_BIT_2	34	/* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_BIT_3	35	/* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_0	BIT(VM_HIGH_ARCH_BIT_0)
#define VM_HIGH_ARCH_1	BIT(VM_HIGH_ARCH_BIT_1)
#define VM_HIGH_ARCH_2	BIT(VM_HIGH_ARCH_BIT_2)
#define VM_HIGH_ARCH_3	BIT(VM_HIGH_ARCH_BIT_3)
#endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */

#if defined(CONFIG_X86)
# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
#if defined (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS)
# define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
# define VM_PKEY_BIT0	VM_HIGH_ARCH_0	/* A protection key is a 4-bit value */
# define VM_PKEY_BIT1	VM_HIGH_ARCH_1
# define VM_PKEY_BIT2	VM_HIGH_ARCH_2
# define VM_PKEY_BIT3	VM_HIGH_ARCH_3
#endif
#elif defined(CONFIG_PPC)
# define VM_SAO		VM_ARCH_1	/* Strong Access Ordering (powerpc) */
#elif defined(CONFIG_PARISC)
# define VM_GROWSUP	VM_ARCH_1
#elif defined(CONFIG_METAG)
# define VM_GROWSUP	VM_ARCH_1
#elif defined(CONFIG_IA64)
# define VM_GROWSUP	VM_ARCH_1
#elif !defined(CONFIG_MMU)
# define VM_MAPPED_COPY	VM_ARCH_1	/* T if mapped copy of data (nommu mmap) */
#endif

#if defined(CONFIG_X86)
/* MPX specific bounds table or bounds directory */
# define VM_MPX		VM_ARCH_2
#endif

#ifndef VM_GROWSUP
# define VM_GROWSUP	VM_NONE
#endif

/* Bits set in the VMA until the stack is in its final location */
#define VM_STACK_INCOMPLETE_SETUP	(VM_RAND_READ | VM_SEQ_READ)

#ifndef VM_STACK_DEFAULT_FLAGS		/* arch can override this */
#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
#endif

#ifdef CONFIG_STACK_GROWSUP
#define VM_STACK	VM_GROWSUP
#else
#define VM_STACK	VM_GROWSDOWN
#endif

#define VM_STACK_FLAGS	(VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)

/*
 * Special vmas that are non-mergable, non-mlock()able.
 * Note: mm/huge_memory.c VM_NO_THP depends on this definition.
 */
#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)

/* This mask defines which mm->def_flags a process can inherit its parent */
#define VM_INIT_DEF_MASK	VM_NOHUGEPAGE

/* This mask is used to clear all the VMA flags used by mlock */
#define VM_LOCKED_CLEAR_MASK	(~(VM_LOCKED | VM_LOCKONFAULT))

/*
 * mapping from the currently active vm_flags protection bits (the
 * low four bits) to a page protection mask..
 */
extern pgprot_t protection_map[16];

#define FAULT_FLAG_WRITE	0x01	/* Fault was a write access */
#define FAULT_FLAG_MKWRITE	0x02	/* Fault was mkwrite of existing pte */
#define FAULT_FLAG_ALLOW_RETRY	0x04	/* Retry fault if blocking */
#define FAULT_FLAG_RETRY_NOWAIT	0x08	/* Don't drop mmap_sem and wait when retrying */
#define FAULT_FLAG_KILLABLE	0x10	/* The fault task is in SIGKILL killable region */
#define FAULT_FLAG_TRIED	0x20	/* Second try */
#define FAULT_FLAG_USER		0x40	/* The fault originated in userspace */
#define FAULT_FLAG_REMOTE	0x80	/* faulting for non current tsk/mm */
#define FAULT_FLAG_INSTRUCTION  0x100	/* The fault was during an instruction fetch */

/*
 * vm_fault is filled by the the pagefault handler and passed to the vma's
 * ->fault function. The vma's ->fault is responsible for returning a bitmask
 * of VM_FAULT_xxx flags that give details about how the fault was handled.
 *
 * MM layer fills up gfp_mask for page allocations but fault handler might
 * alter it if its implementation requires a different allocation context.
 *
 * pgoff should be used in favour of virtual_address, if possible.
 */
struct vm_fault {
	unsigned int flags;		/* FAULT_FLAG_xxx flags */
	gfp_t gfp_mask;			/* gfp mask to be used for allocations */
	pgoff_t pgoff;			/* Logical page offset based on vma */
	void __user *virtual_address;	/* Faulting virtual address */

	struct page *cow_page;		/* Handler may choose to COW */
	struct page *page;		/* ->fault handlers should return a
					 * page here, unless VM_FAULT_NOPAGE
					 * is set (which is also implied by
					 * VM_FAULT_ERROR).
					 */
	void *entry;			/* ->fault handler can alternatively
					 * return locked DAX entry. In that
					 * case handler should return
					 * VM_FAULT_DAX_LOCKED and fill in
					 * entry here.
					 */
};

/*
 * Page fault context: passes though page fault handler instead of endless list
 * of function arguments.
 */
struct fault_env {
	struct vm_area_struct *vma;	/* Target VMA */
	unsigned long address;		/* Faulting virtual address */
	unsigned int flags;		/* FAULT_FLAG_xxx flags */
	pmd_t *pmd;			/* Pointer to pmd entry matching
					 * the 'address'
					 */
	pte_t *pte;			/* Pointer to pte entry matching
					 * the 'address'. NULL if the page
					 * table hasn't been allocated.
					 */
	spinlock_t *ptl;		/* Page table lock.
					 * Protects pte page table if 'pte'
					 * is not NULL, otherwise pmd.
					 */
	pgtable_t prealloc_pte;		/* Pre-allocated pte page table.
					 * vm_ops->map_pages() calls
					 * alloc_set_pte() from atomic context.
					 * do_fault_around() pre-allocates
					 * page table to avoid allocation from
					 * atomic context.
					 */
};

/*
 * These are the virtual MM functions - opening of an area, closing and
 * unmapping it (needed to keep files on disk up-to-date etc), pointer
 * to the functions called when a no-page or a wp-page exception occurs. 
 */
struct vm_operations_struct {
	void (*open)(struct vm_area_struct * area);
	void (*close)(struct vm_area_struct * area);
	int (*mremap)(struct vm_area_struct * area);
	int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
	int (*pmd_fault)(struct vm_area_struct *, unsigned long address,
						pmd_t *, unsigned int flags);
	void (*map_pages)(struct fault_env *fe,
			pgoff_t start_pgoff, pgoff_t end_pgoff);

	/* notification that a previously read-only page is about to become
	 * writable, if an error is returned it will cause a SIGBUS */
	int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);

	/* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
	int (*pfn_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);

	/* called by access_process_vm when get_user_pages() fails, typically
	 * for use by special VMAs that can switch between memory and hardware
	 */
	int (*access)(struct vm_area_struct *vma, unsigned long addr,
		      void *buf, int len, int write);

	/* Called by the /proc/PID/maps code to ask the vma whether it
	 * has a special name.  Returning non-NULL will also cause this
	 * vma to be dumped unconditionally. */
	const char *(*name)(struct vm_area_struct *vma);

#ifdef CONFIG_NUMA
	/*
	 * set_policy() op must add a reference to any non-NULL @new mempolicy
	 * to hold the policy upon return.  Caller should pass NULL @new to
	 * remove a policy and fall back to surrounding context--i.e. do not
	 * install a MPOL_DEFAULT policy, nor the task or system default
	 * mempolicy.
	 */
	int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);

	/*
	 * get_policy() op must add reference [mpol_get()] to any policy at
	 * (vma,addr) marked as MPOL_SHARED.  The shared policy infrastructure
	 * in mm/mempolicy.c will do this automatically.
	 * get_policy() must NOT add a ref if the policy at (vma,addr) is not
	 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
	 * If no [shared/vma] mempolicy exists at the addr, get_policy() op
	 * must return NULL--i.e., do not "fallback" to task or system default
	 * policy.
	 */
	struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
					unsigned long addr);
#endif
	/*
	 * Called by vm_normal_page() for special PTEs to find the
	 * page for @addr.  This is useful if the default behavior
	 * (using pte_page()) would not find the correct page.
	 */
	struct page *(*find_special_page)(struct vm_area_struct *vma,
					  unsigned long addr);
};

struct mmu_gather;
struct inode;

#define page_private(page)		((page)->private)
#define set_page_private(page, v)	((page)->private = (v))

#if !defined(__HAVE_ARCH_PTE_DEVMAP) || !defined(CONFIG_TRANSPARENT_HUGEPAGE)
static inline int pmd_devmap(pmd_t pmd)
{
	return 0;
}
#endif

/*
 * FIXME: take this include out, include page-flags.h in
 * files which need it (119 of them)
 */
#include <linux/page-flags.h>
#include <linux/huge_mm.h>

/*
 * Methods to modify the page usage count.
 *
 * What counts for a page usage:
 * - cache mapping   (page->mapping)
 * - private data    (page->private)
 * - page mapped in a task's page tables, each mapping
 *   is counted separately
 *
 * Also, many kernel routines increase the page count before a critical
 * routine so they can be sure the page doesn't go away from under them.
 */

/*
 * Drop a ref, return true if the refcount fell to zero (the page has no users)
 */
static inline int put_page_testzero(struct page *page)
{
	VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
	return page_ref_dec_and_test(page);
}

/*
 * Try to grab a ref unless the page has a refcount of zero, return false if
 * that is the case.
 * This can be called when MMU is off so it must not access
 * any of the virtual mappings.
 */
static inline int get_page_unless_zero(struct page *page)
{
	return page_ref_add_unless(page, 1, 0);
}

extern int page_is_ram(unsigned long pfn);

enum {
	REGION_INTERSECTS,
	REGION_DISJOINT,
	REGION_MIXED,
};

int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
		      unsigned long desc);

/* Support for virtually mapped pages */
struct page *vmalloc_to_page(const void *addr);
unsigned long vmalloc_to_pfn(const void *addr);

/*
 * Determine if an address is within the vmalloc range
 *
 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
 * is no special casing required.
 */
static inline bool is_vmalloc_addr(const void *x)
{
#ifdef CONFIG_MMU
	unsigned long addr = (unsigned long)x;

	return addr >= VMALLOC_START && addr < VMALLOC_END;
#else
	return false;
#endif
}
#ifdef CONFIG_MMU
extern int is_vmalloc_or_module_addr(const void *x);
#else
static inline int is_vmalloc_or_module_addr(const void *x)
{
	return 0;
}
#endif

extern void kvfree(const void *addr);

static inline atomic_t *compound_mapcount_ptr(struct page *page)
{
	return &page[1].compound_mapcount;
}

static inline int compound_mapcount(struct page *page)
{
	VM_BUG_ON_PAGE(!PageCompound(page), page);
	page = compound_head(page);
	return atomic_read(compound_mapcount_ptr(page)) + 1;
}

/*
 * The atomic page->_mapcount, starts from -1: so that transitions
 * both from it and to it can be tracked, using atomic_inc_and_test
 * and atomic_add_negative(-1).
 */
static inline void page_mapcount_reset(struct page *page)
{
	atomic_set(&(page)->_mapcount, -1);
}

int __page_mapcount(struct page *page);

static inline int page_mapcount(struct page *page)
{
	VM_BUG_ON_PAGE(PageSlab(page), page);

	if (unlikely(PageCompound(page)))
		return __page_mapcount(page);
	return atomic_read(&page->_mapcount) + 1;
}

#ifdef CONFIG_TRANSPARENT_HUGEPAGE
int total_mapcount(struct page *page);
int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
#else
static inline int total_mapcount(struct page *page)
{
	return page_mapcount(page);
}
static inline int page_trans_huge_mapcount(struct page *page,
					   int *total_mapcount)
{
	int mapcount = page_mapcount(page);
	if (total_mapcount)
		*total_mapcount = mapcount;
	return mapcount;
}
#endif

static inline struct page *virt_to_head_page(const void *x)
{
	struct page *page = virt_to_page(x);

	return compound_head(page);
}

void __put_page(struct page *page);

void put_pages_list(struct list_head *pages);

void split_page(struct page *page, unsigned int order);

/*
 * Compound pages have a destructor function.  Provide a
 * prototype for that function and accessor functions.
 * These are _only_ valid on the head of a compound page.
 */
typedef void compound_page_dtor(struct page *);

/* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
enum compound_dtor_id {
	NULL_COMPOUND_DTOR,
	COMPOUND_PAGE_DTOR,
#ifdef CONFIG_HUGETLB_PAGE
	HUGETLB_PAGE_DTOR,
#endif
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
	TRANSHUGE_PAGE_DTOR,
#endif
	NR_COMPOUND_DTORS,
};
extern compound_page_dtor * const compound_page_dtors[];

static inline void set_compound_page_dtor(struct page *page,
		enum compound_dtor_id compound_dtor)
{
	VM_BUG_ON_PAGE(compound_dtor >= NR_COMPOUND_DTORS, page);
	page[1].compound_dtor = compound_dtor;
}

static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
{
	VM_BUG_ON_PAGE(page[1].compound_dtor >= NR_COMPOUND_DTORS, page);
	return compound_page_dtors[page[1].compound_dtor];
}

static inline unsigned int compound_order(struct page *page)
{
	if (!PageHead(page))
		return 0;
	return page[1].compound_order;
}

static inline void set_compound_order(struct page *page, unsigned int order)
{
	page[1].compound_order = order;
}

void free_compound_page(struct page *page);

#ifdef CONFIG_MMU
/*
 * Do pte_mkwrite, but only if the vma says VM_WRITE.  We do this when
 * servicing faults for write access.  In the normal case, do always want
 * pte_mkwrite.  But get_user_pages can cause write faults for mappings
 * that do not have writing enabled, when used by access_process_vm.
 */
static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
{
	if (likely(vma->vm_flags & VM_WRITE))
		pte = pte_mkwrite(pte);
	return pte;
}

int alloc_set_pte(struct fault_env *fe, struct mem_cgroup *memcg,
		struct page *page);
#endif

/*
 * Multiple processes may "see" the same page. E.g. for untouched
 * mappings of /dev/null, all processes see the same page full of
 * zeroes, and text pages of executables and shared libraries have
 * only one copy in memory, at most, normally.
 *
 * For the non-reserved pages, page_count(page) denotes a reference count.
 *   page_count() == 0 means the page is free. page->lru is then used for
 *   freelist management in the buddy allocator.
 *   page_count() > 0  means the page has been allocated.
 *
 * Pages are allocated by the slab allocator in order to provide memory
 * to kmalloc and kmem_cache_alloc. In this case, the management of the
 * page, and the fields in 'struct page' are the responsibility of mm/slab.c
 * unless a particular usage is carefully commented. (the responsibility of
 * freeing the kmalloc memory is the caller's, of course).
 *
 * A page may be used by anyone else who does a __get_free_page().
 * In this case, page_count still tracks the references, and should only
 * be used through the normal accessor functions. The top bits of page->flags
 * and page->virtual store page management information, but all other fields
 * are unused and could be used privately, carefully. The management of this
 * page is the responsibility of the one who allocated it, and those who have
 * subsequently been given references to it.
 *
 * The other pages (we may call them "pagecache pages") are completely
 * managed by the Linux memory manager: I/O, buffers, swapping etc.
 * The following discussion applies only to them.
 *
 * A pagecache page contains an opaque `private' member, which belongs to the
 * page's address_space. Usually, this is the address of a circular list of
 * the page's disk buffers. PG_private must be set to tell the VM to call
 * into the filesystem to release these pages.
 *
 * A page may belong to an inode's memory mapping. In this case, page->mapping
 * is the pointer to the inode, and page->index is the file offset of the page,
 * in units of PAGE_SIZE.
 *
 * If pagecache pages are not associated with an inode, they are said to be
 * anonymous pages. These may become associated with the swapcache, and in that
 * case PG_swapcache is set, and page->private is an offset into the swapcache.
 *
 * In either case (swapcache or inode backed), the pagecache itself holds one
 * reference to the page. Setting PG_private should also increment the
 * refcount. The each user mapping also has a reference to the page.
 *
 * The pagecache pages are stored in a per-mapping radix tree, which is
 * rooted at mapping->page_tree, and indexed by offset.
 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
 * lists, we instead now tag pages as dirty/writeback in the radix tree.
 *
 * All pagecache pages may be subject to I/O:
 * - inode pages may need to be read from disk,
 * - inode pages which have been modified and are MAP_SHARED may need
 *   to be written back to the inode on disk,
 * - anonymous pages (including MAP_PRIVATE file mappings) which have been
 *   modified may need to be swapped out to swap space and (later) to be read
 *   back into memory.
 */

/*
 * The zone field is never updated after free_area_init_core()
 * sets it, so none of the operations on it need to be atomic.
 */

/* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */
#define SECTIONS_PGOFF		((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
#define NODES_PGOFF		(SECTIONS_PGOFF - NODES_WIDTH)
#define ZONES_PGOFF		(NODES_PGOFF - ZONES_WIDTH)
#define LAST_CPUPID_PGOFF	(ZONES_PGOFF - LAST_CPUPID_WIDTH)

/*
 * Define the bit shifts to access each section.  For non-existent
 * sections we define the shift as 0; that plus a 0 mask ensures
 * the compiler will optimise away reference to them.
 */
#define SECTIONS_PGSHIFT	(SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
#define NODES_PGSHIFT		(NODES_PGOFF * (NODES_WIDTH != 0))
#define ZONES_PGSHIFT		(ZONES_PGOFF * (ZONES_WIDTH != 0))
#define LAST_CPUPID_PGSHIFT	(LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0))

/* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
#ifdef NODE_NOT_IN_PAGE_FLAGS
#define ZONEID_SHIFT		(SECTIONS_SHIFT + ZONES_SHIFT)
#define ZONEID_PGOFF		((SECTIONS_PGOFF < ZONES_PGOFF)? \
						SECTIONS_PGOFF : ZONES_PGOFF)
#else
#define ZONEID_SHIFT		(NODES_SHIFT + ZONES_SHIFT)
#define ZONEID_PGOFF		((NODES_PGOFF < ZONES_PGOFF)? \
						NODES_PGOFF : ZONES_PGOFF)
#endif

#define ZONEID_PGSHIFT		(ZONEID_PGOFF * (ZONEID_SHIFT != 0))

#if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
#error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
#endif

#define ZONES_MASK		((1UL << ZONES_WIDTH) - 1)
#define NODES_MASK		((1UL << NODES_WIDTH) - 1)
#define SECTIONS_MASK		((1UL << SECTIONS_WIDTH) - 1)
#define LAST_CPUPID_MASK	((1UL << LAST_CPUPID_SHIFT) - 1)
#define ZONEID_MASK		((1UL << ZONEID_SHIFT) - 1)

static inline enum zone_type page_zonenum(const struct page *page)
{
	return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
}

#ifdef CONFIG_ZONE_DEVICE
void get_zone_device_page(struct page *page);
void put_zone_device_page(struct page *page);
static inline bool is_zone_device_page(const struct page *page)
{
	return page_zonenum(page) == ZONE_DEVICE;
}
#else
static inline void get_zone_device_page(struct page *page)
{
}
static inline void put_zone_device_page(struct page *page)
{
}
static inline bool is_zone_device_page(const struct page *page)
{
	return false;
}
#endif

static inline void get_page(struct page *page)
{
	page = compound_head(page);
	/*
	 * Getting a normal page or the head of a compound page
	 * requires to already have an elevated page->_refcount.
	 */
	VM_BUG_ON_PAGE(page_ref_count(page) <= 0, page);
	page_ref_inc(page);

	if (unlikely(is_zone_device_page(page)))
		get_zone_device_page(page);
}

static inline void put_page(struct page *page)
{
	page = compound_head(page);

	if (put_page_testzero(page))
		__put_page(page);

	if (unlikely(is_zone_device_page(page)))
		put_zone_device_page(page);
}

#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
#define SECTION_IN_PAGE_FLAGS
#endif

/*
 * The identification function is mainly used by the buddy allocator for
 * determining if two pages could be buddies. We are not really identifying
 * the zone since we could be using the section number id if we do not have
 * node id available in page flags.
 * We only guarantee that it will return the same value for two combinable
 * pages in a zone.
 */
static inline int page_zone_id(struct page *page)
{
	return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
}

static inline int zone_to_nid(struct zone *zone)
{
#ifdef CONFIG_NUMA
	return zone->node;
#else
	return 0;
#endif
}

#ifdef NODE_NOT_IN_PAGE_FLAGS
extern int page_to_nid(const struct page *page);
#else
static inline int page_to_nid(const struct page *page)
{
	return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
}
#endif

#ifdef CONFIG_NUMA_BALANCING
static inline int cpu_pid_to_cpupid(int cpu, int pid)
{
	return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
}

static inline int cpupid_to_pid(int cpupid)
{
	return cpupid & LAST__PID_MASK;
}

static inline int cpupid_to_cpu(int cpupid)
{
	return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
}

static inline int cpupid_to_nid(int cpupid)
{
	return cpu_to_node(cpupid_to_cpu(cpupid));
}

static inline bool cpupid_pid_unset(int cpupid)
{
	return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
}

static inline bool cpupid_cpu_unset(int cpupid)
{
	return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
}

static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
{
	return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
}

#define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
{
	return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
}

static inline int page_cpupid_last(struct page *page)
{
	return page->_last_cpupid;
}
static inline void page_cpupid_reset_last(struct page *page)
{
	page->_last_cpupid = -1 & LAST_CPUPID_MASK;
}
#else
static inline int page_cpupid_last(struct page *page)
{
	return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
}

extern int page_cpupid_xchg_last(struct page *page, int cpupid);

static inline void page_cpupid_reset_last(struct page *page)
{
	page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
}
#endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
#else /* !CONFIG_NUMA_BALANCING */
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
{
	return page_to_nid(page); /* XXX */
}

static inline int page_cpupid_last(struct page *page)
{
	return page_to_nid(page); /* XXX */
}

static inline int cpupid_to_nid(int cpupid)
{
	return -1;
}

static inline int cpupid_to_pid(int cpupid)
{
	return -1;
}

static inline int cpupid_to_cpu(int cpupid)
{
	return -1;
}

static inline int cpu_pid_to_cpupid(int nid, int pid)
{
	return -1;
}

static inline bool cpupid_pid_unset(int cpupid)
{
	return 1;
}

static inline void page_cpupid_reset_last(struct page *page)
{
}

static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
{
	return false;
}
#endif /* CONFIG_NUMA_BALANCING */

static inline struct zone *page_zone(const struct page *page)
{
	return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
}

static inline pg_data_t *page_pgdat(const struct page *page)
{
	return NODE_DATA(page_to_nid(page));
}

#ifdef SECTION_IN_PAGE_FLAGS
static inline void set_page_section(struct page *page, unsigned long section)
{
	page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
	page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
}

static inline unsigned long page_to_section(const struct page *page)
{
	return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
}
#endif

static inline void set_page_zone(struct page *page, enum zone_type zone)
{
	page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
	page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
}

static inline void set_page_node(struct page *page, unsigned long node)
{
	page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
	page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
}

static inline void set_page_links(struct page *page, enum zone_type zone,
	unsigned long node, unsigned long pfn)
{
	set_page_zone(page, zone);
	set_page_node(page, node);
#ifdef SECTION_IN_PAGE_FLAGS
	set_page_section(page, pfn_to_section_nr(pfn));
#endif
}

#ifdef CONFIG_MEMCG
static inline struct mem_cgroup *page_memcg(struct page *page)
{
	return page->mem_cgroup;
}
static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
{
	WARN_ON_ONCE(!rcu_read_lock_held());
	return READ_ONCE(page->mem_cgroup);
}
#else
static inline struct mem_cgroup *page_memcg(struct page *page)
{
	return NULL;
}
static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
{
	WARN_ON_ONCE(!rcu_read_lock_held());
	return NULL;
}
#endif

/*
 * Some inline functions in vmstat.h depend on page_zone()
 */
#include <linux/vmstat.h>

static __always_inline void *lowmem_page_address(const struct page *page)
{
	return page_to_virt(page);
}

#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
#define HASHED_PAGE_VIRTUAL
#endif

#if defined(WANT_PAGE_VIRTUAL)
static inline void *page_address(const struct page *page)
{
	return page->virtual;
}
static inline void set_page_address(struct page *page, void *address)
{
	page->virtual = address;
}
#define page_address_init()  do { } while(0)
#endif

#if defined(HASHED_PAGE_VIRTUAL)
void *page_address(const struct page *page);
void set_page_address(struct page *page, void *virtual);
void page_address_init(void);
#endif

#if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
#define page_address(page) lowmem_page_address(page)
#define set_page_address(page, address)  do { } while(0)
#define page_address_init()  do { } while(0)
#endif

extern void *page_rmapping(struct page *page);
extern struct anon_vma *page_anon_vma(struct page *page);
extern struct address_space *page_mapping(struct page *page);

extern struct address_space *__page_file_mapping(struct page *);

static inline
struct address_space *page_file_mapping(struct page *page)
{
	if (unlikely(PageSwapCache(page)))
		return __page_file_mapping(page);

	return page->mapping;
}

extern pgoff_t __page_file_index(struct page *page);

/*
 * Return the pagecache index of the passed page.  Regular pagecache pages
 * use ->index whereas swapcache pages use swp_offset(->private)
 */
static inline pgoff_t page_index(struct page *page)
{
	if (unlikely(PageSwapCache(page)))
		return __page_file_index(page);
	return page->index;
}

bool page_mapped(struct page *page);
struct address_space *page_mapping(struct page *page);

/*
 * Return true only if the page has been allocated with
 * ALLOC_NO_WATERMARKS and the low watermark was not
 * met implying that the system is under some pressure.
 */
static inline bool page_is_pfmemalloc(struct page *page)
{
	/*
	 * Page index cannot be this large so this must be
	 * a pfmemalloc page.
	 */
	return page->index == -1UL;
}

/*
 * Only to be called by the page allocator on a freshly allocated
 * page.
 */
static inline void set_page_pfmemalloc(struct page *page)
{
	page->index = -1UL;
}

static inline void clear_page_pfmemalloc(struct page *page)
{
	page->index = 0;
}

/*
 * Different kinds of faults, as returned by handle_mm_fault().
 * Used to decide whether a process gets delivered SIGBUS or
 * just gets major/minor fault counters bumped up.
 */

#define VM_FAULT_OOM	0x0001
#define VM_FAULT_SIGBUS	0x0002
#define VM_FAULT_MAJOR	0x0004
#define VM_FAULT_WRITE	0x0008	/* Special case for get_user_pages */
#define VM_FAULT_HWPOISON 0x0010	/* Hit poisoned small page */
#define VM_FAULT_HWPOISON_LARGE 0x0020  /* Hit poisoned large page. Index encoded in upper bits */
#define VM_FAULT_SIGSEGV 0x0040

#define VM_FAULT_NOPAGE	0x0100	/* ->fault installed the pte, not return page */
#define VM_FAULT_LOCKED	0x0200	/* ->fault locked the returned page */
#define VM_FAULT_RETRY	0x0400	/* ->fault blocked, must retry */
#define VM_FAULT_FALLBACK 0x0800	/* huge page fault failed, fall back to small */
#define VM_FAULT_DAX_LOCKED 0x1000	/* ->fault has locked DAX entry */

#define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */

#define VM_FAULT_ERROR	(VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
			 VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
			 VM_FAULT_FALLBACK)

/* Encode hstate index for a hwpoisoned large page */
#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)

/*
 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
 */
extern void pagefault_out_of_memory(void);

#define offset_in_page(p)	((unsigned long)(p) & ~PAGE_MASK)

/*
 * Flags passed to show_mem() and show_free_areas() to suppress output in
 * various contexts.
 */
#define SHOW_MEM_FILTER_NODES		(0x0001u)	/* disallowed nodes */

extern void show_free_areas(unsigned int flags);
extern bool skip_free_areas_node(unsigned int flags, int nid);

int shmem_zero_setup(struct vm_area_struct *);
#ifdef CONFIG_SHMEM
bool shmem_mapping(struct address_space *mapping);
#else
static inline bool shmem_mapping(struct address_space *mapping)
{
	return false;
}
#endif

extern bool can_do_mlock(void);
extern int user_shm_lock(size_t, struct user_struct *);
extern void user_shm_unlock(size_t, struct user_struct *);

/*
 * Parameter block passed down to zap_pte_range in exceptional cases.
 */
struct zap_details {
	struct address_space *check_mapping;	/* Check page->mapping if set */
	pgoff_t	first_index;			/* Lowest page->index to unmap */
	pgoff_t last_index;			/* Highest page->index to unmap */
	bool ignore_dirty;			/* Ignore dirty pages */
	bool check_swap_entries;		/* Check also swap entries */
};

struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
		pte_t pte);
struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
				pmd_t pmd);

int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
		unsigned long size);
void zap_page_range(struct vm_area_struct *vma, unsigned long address,
		unsigned long size, struct zap_details *);
void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
		unsigned long start, unsigned long end);

/**
 * mm_walk - callbacks for walk_page_range
 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
 *	       this handler is required to be able to handle
 *	       pmd_trans_huge() pmds.  They may simply choose to
 *	       split_huge_page() instead of handling it explicitly.
 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
 * @pte_hole: if set, called for each hole at all levels
 * @hugetlb_entry: if set, called for each hugetlb entry
 * @test_walk: caller specific callback function to determine whether
 *             we walk over the current vma or not. Returning 0
 *             value means "do page table walk over the current vma,"
 *             and a negative one means "abort current page table walk
 *             right now." 1 means "skip the current vma."
 * @mm:        mm_struct representing the target process of page table walk
 * @vma:       vma currently walked (NULL if walking outside vmas)
 * @private:   private data for callbacks' usage
 *
 * (see the comment on walk_page_range() for more details)
 */
struct mm_walk {
	int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
			 unsigned long next, struct mm_walk *walk);
	int (*pte_entry)(pte_t *pte, unsigned long addr,
			 unsigned long next, struct mm_walk *walk);
	int (*pte_hole)(unsigned long addr, unsigned long next,
			struct mm_walk *walk);
	int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
			     unsigned long addr, unsigned long next,
			     struct mm_walk *walk);
	int (*test_walk)(unsigned long addr, unsigned long next,
			struct mm_walk *walk);
	struct mm_struct *mm;
	struct vm_area_struct *vma;
	void *private;
};

int walk_page_range(unsigned long addr, unsigned long end,
		struct mm_walk *walk);
int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk);
void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
		unsigned long end, unsigned long floor, unsigned long ceiling);
int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
			struct vm_area_struct *vma);
void unmap_mapping_range(struct address_space *mapping,
		loff_t const holebegin, loff_t const holelen, int even_cows);
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
	unsigned long *pfn);
int follow_phys(struct vm_area_struct *vma, unsigned long address,
		unsigned int flags, unsigned long *prot, resource_size_t *phys);
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
			void *buf, int len, int write);

static inline void unmap_shared_mapping_range(struct address_space *mapping,
		loff_t const holebegin, loff_t const holelen)
{
	unmap_mapping_range(mapping, holebegin, holelen, 0);
}

extern void truncate_pagecache(struct inode *inode, loff_t new);
extern void truncate_setsize(struct inode *inode, loff_t newsize);
void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
int truncate_inode_page(struct address_space *mapping, struct page *page);
int generic_error_remove_page(struct address_space *mapping, struct page *page);
int invalidate_inode_page(struct page *page);

#ifdef CONFIG_MMU
extern int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
		unsigned int flags);
extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
			    unsigned long address, unsigned int fault_flags,
			    bool *unlocked);
#else
static inline int handle_mm_fault(struct vm_area_struct *vma,
		unsigned long address, unsigned int flags)
{
	/* should never happen if there's no MMU */
	BUG();
	return VM_FAULT_SIGBUS;
}
static inline int fixup_user_fault(struct task_struct *tsk,
		struct mm_struct *mm, unsigned long address,
		unsigned int fault_flags, bool *unlocked)
{
	/* should never happen if there's no MMU */
	BUG();
	return -EFAULT;
}
#endif

extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len,
		unsigned int gup_flags);
extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
		void *buf, int len, unsigned int gup_flags);

long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
			    unsigned long start, unsigned long nr_pages,
			    unsigned int gup_flags, struct page **pages,
			    struct vm_area_struct **vmas, int *locked);
long get_user_pages(unsigned long start, unsigned long nr_pages,
			    unsigned int gup_flags, struct page **pages,
			    struct vm_area_struct **vmas);
long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
		    unsigned int gup_flags, struct page **pages, int *locked);
long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
			       unsigned long start, unsigned long nr_pages,
			       struct page **pages, unsigned int gup_flags);
long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
		    struct page **pages, unsigned int gup_flags);
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
			struct page **pages);

/* Container for pinned pfns / pages */
struct frame_vector {
	unsigned int nr_allocated;	/* Number of frames we have space for */
	unsigned int nr_frames;	/* Number of frames stored in ptrs array */
	bool got_ref;		/* Did we pin pages by getting page ref? */
	bool is_pfns;		/* Does array contain pages or pfns? */
	void *ptrs[0];		/* Array of pinned pfns / pages. Use
				 * pfns_vector_pages() or pfns_vector_pfns()
				 * for access */
};

struct frame_vector *frame_vector_create(unsigned int nr_frames);
void frame_vector_destroy(struct frame_vector *vec);
int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
		     unsigned int gup_flags, struct frame_vector *vec);
void put_vaddr_frames(struct frame_vector *vec);
int frame_vector_to_pages(struct frame_vector *vec);
void frame_vector_to_pfns(struct frame_vector *vec);

static inline unsigned int frame_vector_count(struct frame_vector *vec)
{
	return vec->nr_frames;
}

static inline struct page **frame_vector_pages(struct frame_vector *vec)
{
	if (vec->is_pfns) {
		int err = frame_vector_to_pages(vec);

		if (err)
			return ERR_PTR(err);
	}
	return (struct page **)(vec->ptrs);
}

static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
{
	if (!vec->is_pfns)
		frame_vector_to_pfns(vec);
	return (unsigned long *)(vec->ptrs);
}

struct kvec;
int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
			struct page **pages);
int get_kernel_page(unsigned long start, int write, struct page **pages);
struct page *get_dump_page(unsigned long addr);

extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
extern void do_invalidatepage(struct page *page, unsigned int offset,
			      unsigned int length);

int __set_page_dirty_nobuffers(struct page *page);
int __set_page_dirty_no_writeback(struct page *page);
int redirty_page_for_writepage(struct writeback_control *wbc,
				struct page *page);
void account_page_dirtied(struct page *page, struct address_space *mapping);
void account_page_cleaned(struct page *page, struct address_space *mapping,
			  struct bdi_writeback *wb);
int set_page_dirty(struct page *page);
int set_page_dirty_lock(struct page *page);
void cancel_dirty_page(struct page *page);
int clear_page_dirty_for_io(struct page *page);

int get_cmdline(struct task_struct *task, char *buffer, int buflen);

/* Is the vma a continuation of the stack vma above it? */
static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr)
{
	return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
}

static inline bool vma_is_anonymous(struct vm_area_struct *vma)
{
	return !vma->vm_ops;
}

static inline int stack_guard_page_start(struct vm_area_struct *vma,
					     unsigned long addr)
{
	return (vma->vm_flags & VM_GROWSDOWN) &&
		(vma->vm_start == addr) &&
		!vma_growsdown(vma->vm_prev, addr);
}

/* Is the vma a continuation of the stack vma below it? */
static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr)
{
	return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP);
}

static inline int stack_guard_page_end(struct vm_area_struct *vma,
					   unsigned long addr)
{
	return (vma->vm_flags & VM_GROWSUP) &&
		(vma->vm_end == addr) &&
		!vma_growsup(vma->vm_next, addr);
}

int vma_is_stack_for_current(struct vm_area_struct *vma);

extern unsigned long move_page_tables(struct vm_area_struct *vma,
		unsigned long old_addr, struct vm_area_struct *new_vma,
		unsigned long new_addr, unsigned long len,
		bool need_rmap_locks);
extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
			      unsigned long end, pgprot_t newprot,
			      int dirty_accountable, int prot_numa);
extern int mprotect_fixup(struct vm_area_struct *vma,
			  struct vm_area_struct **pprev, unsigned long start,
			  unsigned long end, unsigned long newflags);

/*
 * doesn't attempt to fault and will return short.
 */
int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
			  struct page **pages);
/*
 * per-process(per-mm_struct) statistics.
 */
static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
{
	long val = atomic_long_read(&mm->rss_stat.count[member]);

#ifdef SPLIT_RSS_COUNTING
	/*
	 * counter is updated in asynchronous manner and may go to minus.
	 * But it's never be expected number for users.
	 */
	if (val < 0)
		val = 0;
#endif
	return (unsigned long)val;
}

static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
{
	atomic_long_add(value, &mm->rss_stat.count[member]);
}

static inline void inc_mm_counter(struct mm_struct *mm, int member)
{
	atomic_long_inc(&mm->rss_stat.count[member]);
}

static inline void dec_mm_counter(struct mm_struct *mm, int member)
{
	atomic_long_dec(&mm->rss_stat.count[member]);
}

/* Optimized variant when page is already known not to be PageAnon */
static inline int mm_counter_file(struct page *page)
{
	if (PageSwapBacked(page))
		return MM_SHMEMPAGES;
	return MM_FILEPAGES;
}

static inline int mm_counter(struct page *page)
{
	if (PageAnon(page))
		return MM_ANONPAGES;
	return mm_counter_file(page);
}

static inline unsigned long get_mm_rss(struct mm_struct *mm)
{
	return get_mm_counter(mm, MM_FILEPAGES) +
		get_mm_counter(mm, MM_ANONPAGES) +
		get_mm_counter(mm, MM_SHMEMPAGES);
}

static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
{
	return max(mm->hiwater_rss, get_mm_rss(mm));
}

static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
{
	return max(mm->hiwater_vm, mm->total_vm);
}

static inline void update_hiwater_rss(struct mm_struct *mm)
{
	unsigned long _rss = get_mm_rss(mm);

	if ((mm)->hiwater_rss < _rss)
		(mm)->hiwater_rss = _rss;
}

static inline void update_hiwater_vm(struct mm_struct *mm)
{
	if (mm->hiwater_vm < mm->total_vm)
		mm->hiwater_vm = mm->total_vm;
}

static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
{
	mm->hiwater_rss = get_mm_rss(mm);
}

static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
					 struct mm_struct *mm)
{
	unsigned long hiwater_rss = get_mm_hiwater_rss(mm);

	if (*maxrss < hiwater_rss)
		*maxrss = hiwater_rss;
}

#if defined(SPLIT_RSS_COUNTING)
void sync_mm_rss(struct mm_struct *mm);
#else
static inline void sync_mm_rss(struct mm_struct *mm)
{
}
#endif

#ifndef __HAVE_ARCH_PTE_DEVMAP
static inline int pte_devmap(pte_t pte)
{
	return 0;
}
#endif

int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);

extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
			       spinlock_t **ptl);
static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
				    spinlock_t **ptl)
{
	pte_t *ptep;
	__cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
	return ptep;
}

#ifdef __PAGETABLE_PUD_FOLDED
static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
						unsigned long address)
{
	return 0;
}
#else
int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
#endif

#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
						unsigned long address)
{
	return 0;
}

static inline void mm_nr_pmds_init(struct mm_struct *mm) {}

static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
{
	return 0;
}

static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}

#else
int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);

static inline void mm_nr_pmds_init(struct mm_struct *mm)
{
	atomic_long_set(&mm->nr_pmds, 0);
}

static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
{
	return atomic_long_read(&mm->nr_pmds);
}

static inline void mm_inc_nr_pmds(struct mm_struct *mm)
{
	atomic_long_inc(&mm->nr_pmds);
}

static inline void mm_dec_nr_pmds(struct mm_struct *mm)
{
	atomic_long_dec(&mm->nr_pmds);
}
#endif

int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address);
int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);

/*
 * The following ifdef needed to get the 4level-fixup.h header to work.
 * Remove it when 4level-fixup.h has been removed.
 */
#if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
{
	return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
		NULL: pud_offset(pgd, address);
}

static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
{
	return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
		NULL: pmd_offset(pud, address);
}
#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */

#if USE_SPLIT_PTE_PTLOCKS
#if ALLOC_SPLIT_PTLOCKS
void __init ptlock_cache_init(void);
extern bool ptlock_alloc(struct page *page);
extern void ptlock_free(struct page *page);

static inline spinlock_t *ptlock_ptr(struct page *page)
{
	return page->ptl;
}
#else /* ALLOC_SPLIT_PTLOCKS */
static inline void ptlock_cache_init(void)
{
}

static inline bool ptlock_alloc(struct page *page)
{
	return true;
}

static inline void ptlock_free(struct page *page)
{
}

static inline spinlock_t *ptlock_ptr(struct page *page)
{
	return &page->ptl;
}
#endif /* ALLOC_SPLIT_PTLOCKS */

static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
	return ptlock_ptr(pmd_page(*pmd));
}

static inline bool ptlock_init(struct page *page)
{
	/*
	 * prep_new_page() initialize page->private (and therefore page->ptl)
	 * with 0. Make sure nobody took it in use in between.
	 *
	 * It can happen if arch try to use slab for page table allocation:
	 * slab code uses page->slab_cache, which share storage with page->ptl.
	 */
	VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
	if (!ptlock_alloc(page))
		return false;
	spin_lock_init(ptlock_ptr(page));
	return true;
}

/* Reset page->mapping so free_pages_check won't complain. */
static inline void pte_lock_deinit(struct page *page)
{
	page->mapping = NULL;
	ptlock_free(page);
}

#else	/* !USE_SPLIT_PTE_PTLOCKS */
/*
 * We use mm->page_table_lock to guard all pagetable pages of the mm.
 */
static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
	return &mm->page_table_lock;
}
static inline void ptlock_cache_init(void) {}
static inline bool ptlock_init(struct page *page) { return true; }
static inline void pte_lock_deinit(struct page *page) {}
#endif /* USE_SPLIT_PTE_PTLOCKS */

static inline void pgtable_init(void)
{
	ptlock_cache_init();
	pgtable_cache_init();
}

static inline bool pgtable_page_ctor(struct page *page)
{
	if (!ptlock_init(page))
		return false;
	inc_zone_page_state(page, NR_PAGETABLE);
	return true;
}

static inline void pgtable_page_dtor(struct page *page)
{
	pte_lock_deinit(page);
	dec_zone_page_state(page, NR_PAGETABLE);
}

#define pte_offset_map_lock(mm, pmd, address, ptlp)	\
({							\
	spinlock_t *__ptl = pte_lockptr(mm, pmd);	\
	pte_t *__pte = pte_offset_map(pmd, address);	\
	*(ptlp) = __ptl;				\
	spin_lock(__ptl);				\
	__pte;						\
})

#define pte_unmap_unlock(pte, ptl)	do {		\
	spin_unlock(ptl);				\
	pte_unmap(pte);					\
} while (0)

#define pte_alloc(mm, pmd, address)			\
	(unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd, address))

#define pte_alloc_map(mm, pmd, address)			\
	(pte_alloc(mm, pmd, address) ? NULL : pte_offset_map(pmd, address))

#define pte_alloc_map_lock(mm, pmd, address, ptlp)	\
	(pte_alloc(mm, pmd, address) ?			\
		 NULL : pte_offset_map_lock(mm, pmd, address, ptlp))

#define pte_alloc_kernel(pmd, address)			\
	((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
		NULL: pte_offset_kernel(pmd, address))

#if USE_SPLIT_PMD_PTLOCKS

static struct page *pmd_to_page(pmd_t *pmd)
{
	unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
	return virt_to_page((void *)((unsigned long) pmd & mask));
}

static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
	return ptlock_ptr(pmd_to_page(pmd));
}

static inline bool pgtable_pmd_page_ctor(struct page *page)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
	page->pmd_huge_pte = NULL;
#endif
	return ptlock_init(page);
}

static inline void pgtable_pmd_page_dtor(struct page *page)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
	VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
#endif
	ptlock_free(page);
}

#define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte)

#else

static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
	return &mm->page_table_lock;
}

static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; }
static inline void pgtable_pmd_page_dtor(struct page *page) {}

#define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)

#endif

static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
{
	spinlock_t *ptl = pmd_lockptr(mm, pmd);
	spin_lock(ptl);
	return ptl;
}

extern void free_area_init(unsigned long * zones_size);
extern void free_area_init_node(int nid, unsigned long * zones_size,
		unsigned long zone_start_pfn, unsigned long *zholes_size);
extern void free_initmem(void);

/*
 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
 * into the buddy system. The freed pages will be poisoned with pattern
 * "poison" if it's within range [0, UCHAR_MAX].
 * Return pages freed into the buddy system.
 */
extern unsigned long free_reserved_area(void *start, void *end,
					int poison, char *s);

#ifdef	CONFIG_HIGHMEM
/*
 * Free a highmem page into the buddy system, adjusting totalhigh_pages
 * and totalram_pages.
 */
extern void free_highmem_page(struct page *page);
#endif

extern void adjust_managed_page_count(struct page *page, long count);
extern void mem_init_print_info(const char *str);

extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end);

/* Free the reserved page into the buddy system, so it gets managed. */
static inline void __free_reserved_page(struct page *page)
{
	ClearPageReserved(page);
	init_page_count(page);
	__free_page(page);
}

static inline void free_reserved_page(struct page *page)
{
	__free_reserved_page(page);
	adjust_managed_page_count(page, 1);
}

static inline void mark_page_reserved(struct page *page)
{
	SetPageReserved(page);
	adjust_managed_page_count(page, -1);
}

/*
 * Default method to free all the __init memory into the buddy system.
 * The freed pages will be poisoned with pattern "poison" if it's within
 * range [0, UCHAR_MAX].
 * Return pages freed into the buddy system.
 */
static inline unsigned long free_initmem_default(int poison)
{
	extern char __init_begin[], __init_end[];

	return free_reserved_area(&__init_begin, &__init_end,
				  poison, "unused kernel");
}

static inline unsigned long get_num_physpages(void)
{
	int nid;
	unsigned long phys_pages = 0;

	for_each_online_node(nid)
		phys_pages += node_present_pages(nid);

	return phys_pages;
}

#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/*
 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
 * zones, allocate the backing mem_map and account for memory holes in a more
 * architecture independent manner. This is a substitute for creating the
 * zone_sizes[] and zholes_size[] arrays and passing them to
 * free_area_init_node()
 *
 * An architecture is expected to register range of page frames backed by
 * physical memory with memblock_add[_node]() before calling
 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic
 * usage, an architecture is expected to do something like
 *
 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
 * 							 max_highmem_pfn};
 * for_each_valid_physical_page_range()
 * 	memblock_add_node(base, size, nid)
 * free_area_init_nodes(max_zone_pfns);
 *
 * free_bootmem_with_active_regions() calls free_bootmem_node() for each
 * registered physical page range.  Similarly
 * sparse_memory_present_with_active_regions() calls memory_present() for
 * each range when SPARSEMEM is enabled.
 *
 * See mm/page_alloc.c for more information on each function exposed by
 * CONFIG_HAVE_MEMBLOCK_NODE_MAP.
 */
extern void free_area_init_nodes(unsigned long *max_zone_pfn);
unsigned long node_map_pfn_alignment(void);
unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
						unsigned long end_pfn);
extern unsigned long absent_pages_in_range(unsigned long start_pfn,
						unsigned long end_pfn);
extern void get_pfn_range_for_nid(unsigned int nid,
			unsigned long *start_pfn, unsigned long *end_pfn);
extern unsigned long find_min_pfn_with_active_regions(void);
extern void free_bootmem_with_active_regions(int nid,
						unsigned long max_low_pfn);
extern void sparse_memory_present_with_active_regions(int nid);

#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */

#if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \
    !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID)
static inline int __early_pfn_to_nid(unsigned long pfn,
					struct mminit_pfnnid_cache *state)
{
	return 0;
}
#else
/* please see mm/page_alloc.c */
extern int __meminit early_pfn_to_nid(unsigned long pfn);
/* there is a per-arch backend function. */
extern int __meminit __early_pfn_to_nid(unsigned long pfn,
					struct mminit_pfnnid_cache *state);
#endif

extern void set_dma_reserve(unsigned long new_dma_reserve);
extern void memmap_init_zone(unsigned long, int, unsigned long,
				unsigned long, enum memmap_context);
extern void setup_per_zone_wmarks(void);
extern int __meminit init_per_zone_wmark_min(void);
extern void mem_init(void);
extern void __init mmap_init(void);
extern void show_mem(unsigned int flags);
extern long si_mem_available(void);
extern void si_meminfo(struct sysinfo * val);
extern void si_meminfo_node(struct sysinfo *val, int nid);
#ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
extern unsigned long arch_reserved_kernel_pages(void);
#endif

extern __printf(2, 3)
void warn_alloc(gfp_t gfp_mask, const char *fmt, ...);

extern void setup_per_cpu_pageset(void);

extern void zone_pcp_update(struct zone *zone);
extern void zone_pcp_reset(struct zone *zone);

/* page_alloc.c */
extern int min_free_kbytes;
extern int watermark_scale_factor;

/* nommu.c */
extern atomic_long_t mmap_pages_allocated;
extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);

/* interval_tree.c */
void vma_interval_tree_insert(struct vm_area_struct *node,
			      struct rb_root *root);
void vma_interval_tree_insert_after(struct vm_area_struct *node,
				    struct vm_area_struct *prev,
				    struct rb_root *root);
void vma_interval_tree_remove(struct vm_area_struct *node,
			      struct rb_root *root);
struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root,
				unsigned long start, unsigned long last);
struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
				unsigned long start, unsigned long last);

#define vma_interval_tree_foreach(vma, root, start, last)		\
	for (vma = vma_interval_tree_iter_first(root, start, last);	\
	     vma; vma = vma_interval_tree_iter_next(vma, start, last))

void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
				   struct rb_root *root);
void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
				   struct rb_root *root);
struct anon_vma_chain *anon_vma_interval_tree_iter_first(
	struct rb_root *root, unsigned long start, unsigned long last);
struct anon_vma_chain *anon_vma_interval_tree_iter_next(
	struct anon_vma_chain *node, unsigned long start, unsigned long last);
#ifdef CONFIG_DEBUG_VM_RB
void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
#endif

#define anon_vma_interval_tree_foreach(avc, root, start, last)		 \
	for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
	     avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))

/* mmap.c */
extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
extern int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
	unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert,
	struct vm_area_struct *expand);
static inline int vma_adjust(struct vm_area_struct *vma, unsigned long start,
	unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert)
{
	return __vma_adjust(vma, start, end, pgoff, insert, NULL);
}
extern struct vm_area_struct *vma_merge(struct mm_struct *,
	struct vm_area_struct *prev, unsigned long addr, unsigned long end,
	unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
	struct mempolicy *, struct vm_userfaultfd_ctx);
extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
extern int split_vma(struct mm_struct *,
	struct vm_area_struct *, unsigned long addr, int new_below);
extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
	struct rb_node **, struct rb_node *);
extern void unlink_file_vma(struct vm_area_struct *);
extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
	unsigned long addr, unsigned long len, pgoff_t pgoff,
	bool *need_rmap_locks);
extern void exit_mmap(struct mm_struct *);

static inline int check_data_rlimit(unsigned long rlim,
				    unsigned long new,
				    unsigned long start,
				    unsigned long end_data,
				    unsigned long start_data)
{
	if (rlim < RLIM_INFINITY) {
		if (((new - start) + (end_data - start_data)) > rlim)
			return -ENOSPC;
	}

	return 0;
}

extern int mm_take_all_locks(struct mm_struct *mm);
extern void mm_drop_all_locks(struct mm_struct *mm);

extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
extern struct file *get_mm_exe_file(struct mm_struct *mm);
extern struct file *get_task_exe_file(struct task_struct *task);

extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);

extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
				   const struct vm_special_mapping *sm);
extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
				   unsigned long addr, unsigned long len,
				   unsigned long flags,
				   const struct vm_special_mapping *spec);
/* This is an obsolete alternative to _install_special_mapping. */
extern int install_special_mapping(struct mm_struct *mm,
				   unsigned long addr, unsigned long len,
				   unsigned long flags, struct page **pages);

extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);

extern unsigned long mmap_region(struct file *file, unsigned long addr,
	unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
extern unsigned long do_mmap(struct file *file, unsigned long addr,
	unsigned long len, unsigned long prot, unsigned long flags,
	vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate);
extern int do_munmap(struct mm_struct *, unsigned long, size_t);

static inline unsigned long
do_mmap_pgoff(struct file *file, unsigned long addr,
	unsigned long len, unsigned long prot, unsigned long flags,
	unsigned long pgoff, unsigned long *populate)
{
	return do_mmap(file, addr, len, prot, flags, 0, pgoff, populate);
}

#ifdef CONFIG_MMU
extern int __mm_populate(unsigned long addr, unsigned long len,
			 int ignore_errors);
static inline void mm_populate(unsigned long addr, unsigned long len)
{
	/* Ignore errors */
	(void) __mm_populate(addr, len, 1);
}
#else
static inline void mm_populate(unsigned long addr, unsigned long len) {}
#endif

/* These take the mm semaphore themselves */
extern int __must_check vm_brk(unsigned long, unsigned long);
extern int vm_munmap(unsigned long, size_t);
extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
        unsigned long, unsigned long,
        unsigned long, unsigned long);

struct vm_unmapped_area_info {
#define VM_UNMAPPED_AREA_TOPDOWN 1
	unsigned long flags;
	unsigned long length;
	unsigned long low_limit;
	unsigned long high_limit;
	unsigned long align_mask;
	unsigned long align_offset;
};

extern unsigned long unmapped_area(struct vm_unmapped_area_info *info);
extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info);

/*
 * Search for an unmapped address range.
 *
 * We are looking for a range that:
 * - does not intersect with any VMA;
 * - is contained within the [low_limit, high_limit) interval;
 * - is at least the desired size.
 * - satisfies (begin_addr & align_mask) == (align_offset & align_mask)
 */
static inline unsigned long
vm_unmapped_area(struct vm_unmapped_area_info *info)
{
	if (info->flags & VM_UNMAPPED_AREA_TOPDOWN)
		return unmapped_area_topdown(info);
	else
		return unmapped_area(info);
}

/* truncate.c */
extern void truncate_inode_pages(struct address_space *, loff_t);
extern void truncate_inode_pages_range(struct address_space *,
				       loff_t lstart, loff_t lend);
extern void truncate_inode_pages_final(struct address_space *);

/* generic vm_area_ops exported for stackable file systems */
extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
extern void filemap_map_pages(struct fault_env *fe,
		pgoff_t start_pgoff, pgoff_t end_pgoff);
extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);

/* mm/page-writeback.c */
int write_one_page(struct page *page, int wait);
void task_dirty_inc(struct task_struct *tsk);

/* readahead.c */
#define VM_MAX_READAHEAD	128	/* kbytes */
#define VM_MIN_READAHEAD	16	/* kbytes (includes current page) */

int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
			pgoff_t offset, unsigned long nr_to_read);

void page_cache_sync_readahead(struct address_space *mapping,
			       struct file_ra_state *ra,
			       struct file *filp,
			       pgoff_t offset,
			       unsigned long size);

void page_cache_async_readahead(struct address_space *mapping,
				struct file_ra_state *ra,
				struct file *filp,
				struct page *pg,
				pgoff_t offset,
				unsigned long size);

/* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
extern int expand_stack(struct vm_area_struct *vma, unsigned long address);

/* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */
extern int expand_downwards(struct vm_area_struct *vma,
		unsigned long address);
#if VM_GROWSUP
extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
#else
  #define expand_upwards(vma, address) (0)
#endif

/* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
					     struct vm_area_struct **pprev);

/* Look up the first VMA which intersects the interval start_addr..end_addr-1,
   NULL if none.  Assume start_addr < end_addr. */
static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
{
	struct vm_area_struct * vma = find_vma(mm,start_addr);

	if (vma && end_addr <= vma->vm_start)
		vma = NULL;
	return vma;
}

static inline unsigned long vma_pages(struct vm_area_struct *vma)
{
	return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
}

/* Look up the first VMA which exactly match the interval vm_start ... vm_end */
static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
				unsigned long vm_start, unsigned long vm_end)
{
	struct vm_area_struct *vma = find_vma(mm, vm_start);

	if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
		vma = NULL;

	return vma;
}

#ifdef CONFIG_MMU
pgprot_t vm_get_page_prot(unsigned long vm_flags);
void vma_set_page_prot(struct vm_area_struct *vma);
#else
static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
{
	return __pgprot(0);
}
static inline void vma_set_page_prot(struct vm_area_struct *vma)
{
	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
}
#endif

#ifdef CONFIG_NUMA_BALANCING
unsigned long change_prot_numa(struct vm_area_struct *vma,
			unsigned long start, unsigned long end);
#endif

struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
			unsigned long pfn, unsigned long size, pgprot_t);
int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
			unsigned long pfn);
int vm_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
			unsigned long pfn, pgprot_t pgprot);
int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
			pfn_t pfn);
int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);


struct page *follow_page_mask(struct vm_area_struct *vma,
			      unsigned long address, unsigned int foll_flags,
			      unsigned int *page_mask);

static inline struct page *follow_page(struct vm_area_struct *vma,
		unsigned long address, unsigned int foll_flags)
{
	unsigned int unused_page_mask;
	return follow_page_mask(vma, address, foll_flags, &unused_page_mask);
}

#define FOLL_WRITE	0x01	/* check pte is writable */
#define FOLL_TOUCH	0x02	/* mark page accessed */
#define FOLL_GET	0x04	/* do get_page on page */
#define FOLL_DUMP	0x08	/* give error on hole if it would be zero */
#define FOLL_FORCE	0x10	/* get_user_pages read/write w/o permission */
#define FOLL_NOWAIT	0x20	/* if a disk transfer is needed, start the IO
				 * and return without waiting upon it */
#define FOLL_POPULATE	0x40	/* fault in page */
#define FOLL_SPLIT	0x80	/* don't return transhuge pages, split them */
#define FOLL_HWPOISON	0x100	/* check page is hwpoisoned */
#define FOLL_NUMA	0x200	/* force NUMA hinting page fault */
#define FOLL_MIGRATION	0x400	/* wait for page to replace migration entry */
#define FOLL_TRIED	0x800	/* a retry, previous pass started an IO */
#define FOLL_MLOCK	0x1000	/* lock present pages */
#define FOLL_REMOTE	0x2000	/* we are working on non-current tsk/mm */
#define FOLL_COW	0x4000	/* internal GUP flag */

typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
			void *data);
extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
			       unsigned long size, pte_fn_t fn, void *data);


#ifdef CONFIG_PAGE_POISONING
extern bool page_poisoning_enabled(void);
extern void kernel_poison_pages(struct page *page, int numpages, int enable);
extern bool page_is_poisoned(struct page *page);
#else
static inline bool page_poisoning_enabled(void) { return false; }
static inline void kernel_poison_pages(struct page *page, int numpages,
					int enable) { }
static inline bool page_is_poisoned(struct page *page) { return false; }
#endif

#ifdef CONFIG_DEBUG_PAGEALLOC
extern bool _debug_pagealloc_enabled;
extern void __kernel_map_pages(struct page *page, int numpages, int enable);

static inline bool debug_pagealloc_enabled(void)
{
	return _debug_pagealloc_enabled;
}

static inline void
kernel_map_pages(struct page *page, int numpages, int enable)
{
	if (!debug_pagealloc_enabled())
		return;

	__kernel_map_pages(page, numpages, enable);
}
#ifdef CONFIG_HIBERNATION
extern bool kernel_page_present(struct page *page);
#endif	/* CONFIG_HIBERNATION */
#else	/* CONFIG_DEBUG_PAGEALLOC */
static inline void
kernel_map_pages(struct page *page, int numpages, int enable) {}
#ifdef CONFIG_HIBERNATION
static inline bool kernel_page_present(struct page *page) { return true; }
#endif	/* CONFIG_HIBERNATION */
static inline bool debug_pagealloc_enabled(void)
{
	return false;
}
#endif	/* CONFIG_DEBUG_PAGEALLOC */

#ifdef __HAVE_ARCH_GATE_AREA
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
extern int in_gate_area_no_mm(unsigned long addr);
extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
#else
static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
	return NULL;
}
static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
	return 0;
}
#endif	/* __HAVE_ARCH_GATE_AREA */

extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);

#ifdef CONFIG_SYSCTL
extern int sysctl_drop_caches;
int drop_caches_sysctl_handler(struct ctl_table *, int,
					void __user *, size_t *, loff_t *);
#endif

void drop_slab(void);
void drop_slab_node(int nid);

#ifndef CONFIG_MMU
#define randomize_va_space 0
#else
extern int randomize_va_space;
#endif

const char * arch_vma_name(struct vm_area_struct *vma);
void print_vma_addr(char *prefix, unsigned long rip);

void sparse_mem_maps_populate_node(struct page **map_map,
				   unsigned long pnum_begin,
				   unsigned long pnum_end,
				   unsigned long map_count,
				   int nodeid);

struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
void *vmemmap_alloc_block(unsigned long size, int node);
struct vmem_altmap;
void *__vmemmap_alloc_block_buf(unsigned long size, int node,
		struct vmem_altmap *altmap);
static inline void *vmemmap_alloc_block_buf(unsigned long size, int node)
{
	return __vmemmap_alloc_block_buf(size, node, NULL);
}

void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
int vmemmap_populate_basepages(unsigned long start, unsigned long end,
			       int node);
int vmemmap_populate(unsigned long start, unsigned long end, int node);
void vmemmap_populate_print_last(void);
#ifdef CONFIG_MEMORY_HOTPLUG
void vmemmap_free(unsigned long start, unsigned long end);
#endif
void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
				  unsigned long size);

enum mf_flags {
	MF_COUNT_INCREASED = 1 << 0,
	MF_ACTION_REQUIRED = 1 << 1,
	MF_MUST_KILL = 1 << 2,
	MF_SOFT_OFFLINE = 1 << 3,
};
extern int memory_failure(unsigned long pfn, int trapno, int flags);
extern void memory_failure_queue(unsigned long pfn, int trapno, int flags);
extern int unpoison_memory(unsigned long pfn);
extern int get_hwpoison_page(struct page *page);
#define put_hwpoison_page(page)	put_page(page)
extern int sysctl_memory_failure_early_kill;
extern int sysctl_memory_failure_recovery;
extern void shake_page(struct page *p, int access);
extern atomic_long_t num_poisoned_pages;
extern int soft_offline_page(struct page *page, int flags);


/*
 * Error handlers for various types of pages.
 */
enum mf_result {
	MF_IGNORED,	/* Error: cannot be handled */
	MF_FAILED,	/* Error: handling failed */
	MF_DELAYED,	/* Will be handled later */
	MF_RECOVERED,	/* Successfully recovered */
};

enum mf_action_page_type {
	MF_MSG_KERNEL,
	MF_MSG_KERNEL_HIGH_ORDER,
	MF_MSG_SLAB,
	MF_MSG_DIFFERENT_COMPOUND,
	MF_MSG_POISONED_HUGE,
	MF_MSG_HUGE,
	MF_MSG_FREE_HUGE,
	MF_MSG_UNMAP_FAILED,
	MF_MSG_DIRTY_SWAPCACHE,
	MF_MSG_CLEAN_SWAPCACHE,
	MF_MSG_DIRTY_MLOCKED_LRU,
	MF_MSG_CLEAN_MLOCKED_LRU,
	MF_MSG_DIRTY_UNEVICTABLE_LRU,
	MF_MSG_CLEAN_UNEVICTABLE_LRU,
	MF_MSG_DIRTY_LRU,
	MF_MSG_CLEAN_LRU,
	MF_MSG_TRUNCATED_LRU,
	MF_MSG_BUDDY,
	MF_MSG_BUDDY_2ND,
	MF_MSG_UNKNOWN,
};

#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
extern void clear_huge_page(struct page *page,
			    unsigned long addr,
			    unsigned int pages_per_huge_page);
extern void copy_user_huge_page(struct page *dst, struct page *src,
				unsigned long addr, struct vm_area_struct *vma,
				unsigned int pages_per_huge_page);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */

extern struct page_ext_operations debug_guardpage_ops;
extern struct page_ext_operations page_poisoning_ops;

#ifdef CONFIG_DEBUG_PAGEALLOC
extern unsigned int _debug_guardpage_minorder;
extern bool _debug_guardpage_enabled;

static inline unsigned int debug_guardpage_minorder(void)
{
	return _debug_guardpage_minorder;
}

static inline bool debug_guardpage_enabled(void)
{
	return _debug_guardpage_enabled;
}

static inline bool page_is_guard(struct page *page)
{
	struct page_ext *page_ext;

	if (!debug_guardpage_enabled())
		return false;

	page_ext = lookup_page_ext(page);
	if (unlikely(!page_ext))
		return false;

	return test_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
}
#else
static inline unsigned int debug_guardpage_minorder(void) { return 0; }
static inline bool debug_guardpage_enabled(void) { return false; }
static inline bool page_is_guard(struct page *page) { return false; }
#endif /* CONFIG_DEBUG_PAGEALLOC */

#if MAX_NUMNODES > 1
void __init setup_nr_node_ids(void);
#else
static inline void setup_nr_node_ids(void) {}
#endif

#endif /* __KERNEL__ */
#endif /* _LINUX_MM_H */