fs/compat_binfmt_elf.c

   1 /*
   2  * 32-bit compatibility support for ELF format executables and core dumps.
   3  *
   4  * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.
   5  *
   6  * This copyrighted material is made available to anyone wishing to use,
   7  * modify, copy, or redistribute it subject to the terms and conditions
   8  * of the GNU General Public License v.2.
   9  *
  10  * Red Hat Author: Roland McGrath.
  11  *
  12  * This file is used in a 64-bit kernel that wants to support 32-bit ELF.
  13  * asm/elf.h is responsible for defining the compat_* and COMPAT_* macros
  14  * used below, with definitions appropriate for 32-bit ABI compatibility.
  15  *
  16  * We use macros to rename the ABI types and machine-dependent
  17  * functions used in binfmt_elf.c to compat versions.
  18  */
  19
  20 #include <linux/elfcore-compat.h>
  21 #include <linux/time.h>
  22
  23 /*
  24  * Rename the basic ELF layout types to refer to the 32-bit class of files.
  25  */
  26 #undef  ELF_CLASS
  27 #define ELF_CLASS       ELFCLASS32
  28
  29 #undef  elfhdr
  30 #undef  elf_phdr
  31 #undef  elf_shdr
  32 #undef  elf_note
  33 #undef  elf_addr_t
  34 #define elfhdr          elf32_hdr
  35 #define elf_phdr        elf32_phdr
  36 #define elf_shdr        elf32_shdr
  37 #define elf_note        elf32_note
  38 #define elf_addr_t      Elf32_Addr
  39
  40 /*
  41  * Some data types as stored in coredump.
  42  */
  43 #define user_long_t             compat_long_t
  44 #define user_siginfo_t          compat_siginfo_t
  45 #define copy_siginfo_to_user    copy_siginfo_to_user32
  46
  47 /*
  48  * The machine-dependent core note format types are defined in elfcore-compat.h,
  49  * which requires asm/elf.h to define compat_elf_gregset_t et al.
  50  */
  51 #define elf_prstatus    compat_elf_prstatus
  52 #define elf_prpsinfo    compat_elf_prpsinfo
  53
  54 #ifdef CONFIG_ELF_CORE
  55 /*
  56  * Compat version of cputime_to_compat_timeval, perhaps this
  57  * should be an inline in <linux/compat.h>.
  58  */
  59 static void cputime_to_compat_timeval(const cputime_t cputime,
  60                                       struct compat_timeval *value)
  61 {
  62         struct timeval tv;
  63         cputime_to_timeval(cputime, &tv);
  64         value->tv_sec = tv.tv_sec;
  65         value->tv_usec = tv.tv_usec;
  66 }
  67 #endif
  68
  69 #undef cputime_to_timeval
  70 #define cputime_to_timeval cputime_to_compat_timeval
  71
  72
  73 /*
  74  * To use this file, asm/elf.h must define compat_elf_check_arch.
  75  * The other following macros can be defined if the compat versions
  76  * differ from the native ones, or omitted when they match.
  77  */
  78
  79 #undef  ELF_ARCH
  80 #undef  elf_check_arch
  81 #define elf_check_arch  compat_elf_check_arch
  82
  83 #ifdef  COMPAT_ELF_PLATFORM
  84 #undef  ELF_PLATFORM
  85 #define ELF_PLATFORM            COMPAT_ELF_PLATFORM
  86 #endif
  87
  88 #ifdef  COMPAT_ELF_HWCAP
  89 #undef  ELF_HWCAP
  90 #define ELF_HWCAP               COMPAT_ELF_HWCAP
  91 #endif
  92
  93 #ifdef  COMPAT_ELF_HWCAP2
  94 #undef  ELF_HWCAP2
  95 #define ELF_HWCAP2              COMPAT_ELF_HWCAP2
  96 #endif
  97
  98 #ifdef  COMPAT_ARCH_DLINFO
  99 #undef  ARCH_DLINFO
 100 #define ARCH_DLINFO             COMPAT_ARCH_DLINFO
 101 #endif
 102
 103 #ifdef  COMPAT_ELF_ET_DYN_BASE
 104 #undef  ELF_ET_DYN_BASE
 105 #define ELF_ET_DYN_BASE         COMPAT_ELF_ET_DYN_BASE
 106 #endif
 107
 108 #ifdef COMPAT_ELF_EXEC_PAGESIZE
 109 #undef  ELF_EXEC_PAGESIZE
 110 #define ELF_EXEC_PAGESIZE       COMPAT_ELF_EXEC_PAGESIZE
 111 #endif
 112
 113 #ifdef  COMPAT_ELF_PLAT_INIT
 114 #undef  ELF_PLAT_INIT
 115 #define ELF_PLAT_INIT           COMPAT_ELF_PLAT_INIT
 116 #endif
 117
 118 #ifdef  COMPAT_SET_PERSONALITY
 119 #undef  SET_PERSONALITY
 120 #define SET_PERSONALITY         COMPAT_SET_PERSONALITY
 121 #endif
 122
 123 #ifdef  compat_start_thread
 124 #undef  start_thread
 125 #define start_thread            compat_start_thread
 126 #endif
 127
 128 #ifdef  compat_arch_setup_additional_pages
 129 #undef  ARCH_HAS_SETUP_ADDITIONAL_PAGES
 130 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
 131 #undef  arch_setup_additional_pages
 132 #define arch_setup_additional_pages compat_arch_setup_additional_pages
 133 #endif
 134
 135 /*
 136  * Rename a few of the symbols that binfmt_elf.c will define.
 137  * These are all local so the names don't really matter, but it
 138  * might make some debugging less confusing not to duplicate them.
 139  */
 140 #define elf_format              compat_elf_format
 141 #define init_elf_binfmt         init_compat_elf_binfmt
 142 #define exit_elf_binfmt         exit_compat_elf_binfmt
 143
 144 /*
 145  * We share all the actual code with the native (64-bit) version.
 146  */
 147 #include "binfmt_elf.c"