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 /*
55 * Compat version of cputime_to_compat_timeval, perhaps this
56 * should be an inline in <linux/compat.h>.
57 */
cputime_to_compat_timeval(const cputime_t cputime,struct compat_timeval * value)58 static void cputime_to_compat_timeval(const cputime_t cputime,
59 struct compat_timeval *value)
60 {
61 struct timeval tv;
62 cputime_to_timeval(cputime, &tv);
63 value->tv_sec = tv.tv_sec;
64 value->tv_usec = tv.tv_usec;
65 }
66
67 #undef cputime_to_timeval
68 #define cputime_to_timeval cputime_to_compat_timeval
69
70
71 /*
72 * To use this file, asm/elf.h must define compat_elf_check_arch.
73 * The other following macros can be defined if the compat versions
74 * differ from the native ones, or omitted when they match.
75 */
76
77 #undef ELF_ARCH
78 #undef elf_check_arch
79 #define elf_check_arch compat_elf_check_arch
80
81 #ifdef COMPAT_ELF_PLATFORM
82 #undef ELF_PLATFORM
83 #define ELF_PLATFORM COMPAT_ELF_PLATFORM
84 #endif
85
86 #ifdef COMPAT_ELF_HWCAP
87 #undef ELF_HWCAP
88 #define ELF_HWCAP COMPAT_ELF_HWCAP
89 #endif
90
91 #ifdef COMPAT_ELF_HWCAP2
92 #undef ELF_HWCAP2
93 #define ELF_HWCAP2 COMPAT_ELF_HWCAP2
94 #endif
95
96 #ifdef COMPAT_ARCH_DLINFO
97 #undef ARCH_DLINFO
98 #define ARCH_DLINFO COMPAT_ARCH_DLINFO
99 #endif
100
101 #ifdef COMPAT_ELF_ET_DYN_BASE
102 #undef ELF_ET_DYN_BASE
103 #define ELF_ET_DYN_BASE COMPAT_ELF_ET_DYN_BASE
104 #endif
105
106 #ifdef COMPAT_ELF_EXEC_PAGESIZE
107 #undef ELF_EXEC_PAGESIZE
108 #define ELF_EXEC_PAGESIZE COMPAT_ELF_EXEC_PAGESIZE
109 #endif
110
111 #ifdef COMPAT_ELF_PLAT_INIT
112 #undef ELF_PLAT_INIT
113 #define ELF_PLAT_INIT COMPAT_ELF_PLAT_INIT
114 #endif
115
116 #ifdef COMPAT_SET_PERSONALITY
117 #undef SET_PERSONALITY
118 #define SET_PERSONALITY COMPAT_SET_PERSONALITY
119 #endif
120
121 #ifdef compat_start_thread
122 #undef start_thread
123 #define start_thread compat_start_thread
124 #endif
125
126 #ifdef compat_arch_setup_additional_pages
127 #undef ARCH_HAS_SETUP_ADDITIONAL_PAGES
128 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
129 #undef arch_setup_additional_pages
130 #define arch_setup_additional_pages compat_arch_setup_additional_pages
131 #endif
132
133 /*
134 * Rename a few of the symbols that binfmt_elf.c will define.
135 * These are all local so the names don't really matter, but it
136 * might make some debugging less confusing not to duplicate them.
137 */
138 #define elf_format compat_elf_format
139 #define init_elf_binfmt init_compat_elf_binfmt
140 #define exit_elf_binfmt exit_compat_elf_binfmt
141
142 /*
143 * We share all the actual code with the native (64-bit) version.
144 */
145 #include "binfmt_elf.c"
146