1 /* Definitions for BSD-style memory management. 2 Copyright (C) 1994-2022 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 /* These are the bits used by 4.4 BSD and its derivatives. On systems 20 (such as GNU) where these facilities are not system services but can be 21 emulated in the C library, these are the definitions we emulate. */ 22 23 #ifndef _SYS_MMAN_H 24 # error "Never use <bits/mman.h> directly; include <sys/mman.h> instead." 25 #endif 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_NONE 0x00 /* No access. */ 33 #define PROT_READ 0x04 /* Pages can be read. */ 34 #define PROT_WRITE 0x02 /* Pages can be written. */ 35 #define PROT_EXEC 0x01 /* Pages can be executed. */ 36 37 /* Flags contain mapping type, sharing type and options. */ 38 39 /* Mapping type (must choose one and only one of these). */ 40 #ifdef __USE_MISC 41 # define MAP_FILE 0x0001 /* Mapped from a file or device. */ 42 # define MAP_ANON 0x0002 /* Allocated from anonymous virtual memory. */ 43 # define MAP_TYPE 0x000f /* Mask for type field. */ 44 # define MAP_ANONYMOUS MAP_ANON /* Linux name. */ 45 #endif 46 47 /* Sharing types (must choose one and only one of these). */ 48 #ifdef __USE_MISC 49 # define MAP_COPY 0x0020 /* Virtual copy of region at mapping time. */ 50 #endif 51 #define MAP_SHARED 0x0010 /* Share changes. */ 52 #define MAP_PRIVATE 0x0000 /* Changes private; copy pages on write. */ 53 54 /* Other flags. */ 55 #define MAP_FIXED 0x0100 /* Map address must be exactly as requested. */ 56 #ifdef __USE_MISC 57 # define MAP_NOEXTEND 0x0200 /* For MAP_FILE, don't change file size. */ 58 # define MAP_HASSEMPHORE 0x0400 /* Region may contain semaphores. */ 59 # define MAP_INHERIT 0x0800 /* Region is retained after exec. */ 60 #endif 61 62 /* Advice to `madvise'. */ 63 #ifdef __USE_MISC 64 # define MADV_NORMAL 0 /* No further special treatment. */ 65 # define MADV_RANDOM 1 /* Expect random page references. */ 66 # define MADV_SEQUENTIAL 2 /* Expect sequential page references. */ 67 # define MADV_WILLNEED 3 /* Will need these pages. */ 68 # define MADV_DONTNEED 4 /* Don't need these pages. */ 69 #endif 70 71 /* The POSIX people had to invent similar names for the same things. */ 72 #ifdef __USE_XOPEN2K 73 # define POSIX_MADV_NORMAL 0 /* No further special treatment. */ 74 # define POSIX_MADV_RANDOM 1 /* Expect random page references. */ 75 # define POSIX_MADV_SEQUENTIAL 2 /* Expect sequential page references. */ 76 # define POSIX_MADV_WILLNEED 3 /* Will need these pages. */ 77 # define POSIX_MADV_DONTNEED 4 /* Don't need these pages. */ 78 #endif 79 80 /* Flags to `msync'. */ 81 #define MS_ASYNC 1 /* Sync memory asynchronously. */ 82 #define MS_SYNC 0 /* Synchronous memory sync. */ 83 #define MS_INVALIDATE 2 /* Invalidate the caches. */ 84 85 /* Flags for `mremap'. */ 86 #ifdef __USE_GNU 87 # define MREMAP_MAYMOVE 1 /* Mapping address may change. */ 88 # define MREMAP_FIXED 2 /* Fifth argument sets new address. */ 89 #endif 90 91 /* Flags for `mlockall' (can be OR'd together). */ 92 #define MCL_CURRENT 1 /* Lock all currently mapped pages. */ 93 #define MCL_FUTURE 2 /* Lock all additions to address 94 space. */ 95