sysdeps/unix/sysv/linux/bits/mman-shared.h

   1 /* Memory-mapping-related declarations/definitions, not architecture-specific.
   2    Copyright (C) 2017-2019 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-shared.h> directly; include <sys/mman.h> instead."
  21 #endif
  22
  23 #ifdef __USE_GNU
  24 /* Flags for mremap.  */
  25 # define MREMAP_MAYMOVE 1
  26 # define MREMAP_FIXED   2
  27
  28 /* Flags for memfd_create.  */
  29 # ifndef MFD_CLOEXEC
  30 #  define MFD_CLOEXEC 1U
  31 #  define MFD_ALLOW_SEALING 2U
  32 #  define MFD_HUGETLB 4U
  33 # endif
  34
  35 /* Flags for mlock2.  */
  36 # ifndef MLOCK_ONFAULT
  37 #  define MLOCK_ONFAULT 1U
  38 # endif
  39
  40 /* Access rights for pkey_alloc.  */
  41 # ifndef PKEY_DISABLE_ACCESS
  42 #  define PKEY_DISABLE_ACCESS 0x1
  43 #  define PKEY_DISABLE_WRITE 0x2
  44 # endif
  45
  46 __BEGIN_DECLS
  47
  48 /* Create a new memory file descriptor.  NAME is a name for debugging.
  49    FLAGS is a combination of the MFD_* constants.  */
  50 int memfd_create (const char *__name, unsigned int __flags) __THROW;
  51
  52 /* Lock pages from ADDR (inclusive) to ADDR + LENGTH (exclusive) into
  53    memory.  FLAGS is a combination of the MLOCK_* flags above.  */
  54 int mlock2 (const void *__addr, size_t __length, unsigned int __flags) __THROW;
  55
  56 /* Allocate a new protection key, with the PKEY_DISABLE_* bits
  57    specified in ACCESS_RIGHTS.  The protection key mask for the
  58    current thread is updated to match the access privilege for the new
  59    key.  */
  60 int pkey_alloc (unsigned int __flags, unsigned int __access_rights) __THROW;
  61
  62 /* Update the access rights for the current thread for KEY, which must
  63    have been allocated using pkey_alloc.  */
  64 int pkey_set (int __key, unsigned int __access_rights) __THROW;
  65
  66 /* Return the access rights for the current thread for KEY, which must
  67    have been allocated using pkey_alloc.  */
  68 int pkey_get (int __key) __THROW;
  69
  70 /* Free an allocated protection key, which must have been allocated
  71    using pkey_alloc.  */
  72 int pkey_free (int __key) __THROW;
  73
  74 /* Apply memory protection flags for KEY to the specified address
  75    range.  */
  76 int pkey_mprotect (void *__addr, size_t __len, int __prot, int __pkey) __THROW;
  77
  78 __END_DECLS
  79
  80 #endif /* __USE_GNU */