1/* Definitions for POSIX memory map interface. Linux generic version.
2 Copyright (C) 2001-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _SYS_MMAN_H
20# error "Never use <bits/mman-linux.h> directly; include <sys/mman.h> instead."
21#endif
22
23/* The following definitions basically come from the kernel headers.
24 But the kernel header is not namespace clean. */
25
26
27/* Protections are chosen from these bits, OR'd together. The
28 implementation does not necessarily support PROT_EXEC or PROT_WRITE
29 without PROT_READ. The only guarantees are that no writing will be
30 allowed without PROT_WRITE and no access will be allowed for PROT_NONE. */
31
32#define PROT_READ 0x1 /* Page can be read. */
33#define PROT_WRITE 0x2 /* Page can be written. */
34#define PROT_EXEC 0x4 /* Page can be executed. */
35#define PROT_NONE 0x0 /* Page can not be accessed. */
36#define PROT_GROWSDOWN 0x01000000 /* Extend change to start of
37 growsdown vma (mprotect only). */
38#define PROT_GROWSUP 0x02000000 /* Extend change to start of
39 growsup vma (mprotect only). */
40
41/* Sharing types (must choose one and only one of these). */
42#define MAP_SHARED 0x01 /* Share changes. */
43#define MAP_PRIVATE 0x02 /* Changes are private. */
44#define MAP_SHARED_VALIDATE 0x03 /* Share changes and validate
45 extension flags. */
46#define MAP_TYPE 0x0f /* Mask for type of mapping. */
47
48/* Other flags. */
49#define MAP_FIXED 0x10 /* Interpret addr exactly. */
50#define MAP_FILE 0
51#ifdef __MAP_ANONYMOUS
52# define MAP_ANONYMOUS __MAP_ANONYMOUS /* Don't use a file. */
53#else
54# define MAP_ANONYMOUS 0x20 /* Don't use a file. */
55#endif
56#define MAP_ANON MAP_ANONYMOUS
57/* When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size. */
58#define MAP_HUGE_SHIFT 26
59#define MAP_HUGE_MASK 0x3f
60
61/* Flags to `msync'. */
62#define MS_ASYNC 1 /* Sync memory asynchronously. */
63#define MS_SYNC 4 /* Synchronous memory sync. */
64#define MS_INVALIDATE 2 /* Invalidate the caches. */
65
66/* Advice to `madvise'. */
67#ifdef __USE_MISC
68# define MADV_NORMAL 0 /* No further special treatment. */
69# define MADV_RANDOM 1 /* Expect random page references. */
70# define MADV_SEQUENTIAL 2 /* Expect sequential page references. */
71# define MADV_WILLNEED 3 /* Will need these pages. */
72# define MADV_DONTNEED 4 /* Don't need these pages. */
73# define MADV_FREE 8 /* Free pages only if memory pressure. */
74# define MADV_REMOVE 9 /* Remove these pages and resources. */
75# define MADV_DONTFORK 10 /* Do not inherit across fork. */
76# define MADV_DOFORK 11 /* Do inherit across fork. */
77# define MADV_MERGEABLE 12 /* KSM may merge identical pages. */
78# define MADV_UNMERGEABLE 13 /* KSM may not merge identical pages. */
79# define MADV_HUGEPAGE 14 /* Worth backing with hugepages. */
80# define MADV_NOHUGEPAGE 15 /* Not worth backing with hugepages. */
81# define MADV_DONTDUMP 16 /* Explicitly exclude from the core dump,
82 overrides the coredump filter bits. */
83# define MADV_DODUMP 17 /* Clear the MADV_DONTDUMP flag. */
84# define MADV_WIPEONFORK 18 /* Zero memory on fork, child only. */
85# define MADV_KEEPONFORK 19 /* Undo MADV_WIPEONFORK. */
86# define MADV_COLD 20 /* Deactivate these pages. */
87# define MADV_PAGEOUT 21 /* Reclaim these pages. */
88# define MADV_POPULATE_READ 22 /* Populate (prefault) page tables
89 readable. */
90# define MADV_POPULATE_WRITE 23 /* Populate (prefault) page tables
91 writable. */
92# define MADV_DONTNEED_LOCKED 24 /* Like MADV_DONTNEED, but drop
93 locked pages too. */
94# define MADV_COLLAPSE 25 /* Synchronous hugepage collapse. */
95# define MADV_HWPOISON 100 /* Poison a page for testing. */
96#endif
97
98/* The POSIX people had to invent similar names for the same things. */
99#ifdef __USE_XOPEN2K
100# define POSIX_MADV_NORMAL 0 /* No further special treatment. */
101# define POSIX_MADV_RANDOM 1 /* Expect random page references. */
102# define POSIX_MADV_SEQUENTIAL 2 /* Expect sequential page references. */
103# define POSIX_MADV_WILLNEED 3 /* Will need these pages. */
104# define POSIX_MADV_DONTNEED 4 /* Don't need these pages. */
105#endif
106
107/* Flags for `mlockall'. */
108#ifndef MCL_CURRENT
109# define MCL_CURRENT 1 /* Lock all currently mapped pages. */
110# define MCL_FUTURE 2 /* Lock all additions to address
111 space. */
112# define MCL_ONFAULT 4 /* Lock all pages that are
113 faulted in. */
114#endif
115
116#include <bits/mman-shared.h>
117

source code of glibc/sysdeps/unix/sysv/linux/bits/mman-linux.h