From 2f79e48ae2651fff08d08dab3acf1294467c1155 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 30 Jan 2008 13:31:46 +0100 Subject: [PATCH] x86: compat_binfmt_elf This adds fs/compat_binfmt_elf.c, a wrapper around fs/binfmt_elf.c for 32-bit ELF support on 64-bit kernels. It can replace all the hand-rolled versions of this that each 32/64 arch has, which are all about the same. To use this, an arch's asm/elf.h has to define at least a few compat_* macros that parallel the various macros that fs/binfmt_elf.c uses for native support. There is no attempt to deal with compat macros for the core dump format support. To use this file, the arch has to define compat_gregset_t for linux/elfcore-compat.h and #define CORE_DUMP_USE_REGSET. The 32-bit compatible formats should come automatically from task_user_regset_view called on a 32-bit task. Signed-off-by: Roland McGrath Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- fs/compat_binfmt_elf.c | 131 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+) create mode 100644 fs/compat_binfmt_elf.c diff --git a/fs/compat_binfmt_elf.c b/fs/compat_binfmt_elf.c new file mode 100644 index 0000000000..0adced2f29 --- /dev/null +++ b/fs/compat_binfmt_elf.c @@ -0,0 +1,131 @@ +/* + * 32-bit compatibility support for ELF format executables and core dumps. + * + * Copyright (C) 2007 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License v.2. + * + * Red Hat Author: Roland McGrath. + * + * This file is used in a 64-bit kernel that wants to support 32-bit ELF. + * asm/elf.h is responsible for defining the compat_* and COMPAT_* macros + * used below, with definitions appropriate for 32-bit ABI compatibility. + * + * We use macros to rename the ABI types and machine-dependent + * functions used in binfmt_elf.c to compat versions. + */ + +#include +#include + +/* + * Rename the basic ELF layout types to refer to the 32-bit class of files. + */ +#undef ELF_CLASS +#define ELF_CLASS ELFCLASS32 + +#undef elfhdr +#undef elf_phdr +#undef elf_note +#undef elf_addr_t +#define elfhdr elf32_hdr +#define elf_phdr elf32_phdr +#define elf_note elf32_note +#define elf_addr_t Elf32_Addr + +/* + * The machine-dependent core note format types are defined in elfcore-compat.h, + * which requires asm/elf.h to define compat_elf_gregset_t et al. + */ +#define elf_prstatus compat_elf_prstatus +#define elf_prpsinfo compat_elf_prpsinfo + +/* + * Compat version of cputime_to_compat_timeval, perhaps this + * should be an inline in . + */ +static void cputime_to_compat_timeval(const cputime_t cputime, + struct compat_timeval *value) +{ + struct timeval tv; + cputime_to_timeval(cputime, &tv); + value->tv_sec = tv.tv_sec; + value->tv_usec = tv.tv_usec; +} + +#undef cputime_to_timeval +#define cputime_to_timeval cputime_to_compat_timeval + + +/* + * To use this file, asm/elf.h must define compat_elf_check_arch. + * The other following macros can be defined if the compat versions + * differ from the native ones, or omitted when they match. + */ + +#undef ELF_ARCH +#undef elf_check_arch +#define elf_check_arch compat_elf_check_arch + +#ifdef COMPAT_ELF_PLATFORM +#undef ELF_PLATFORM +#define ELF_PLATFORM COMPAT_ELF_PLATFORM +#endif + +#ifdef COMPAT_ELF_HWCAP +#undef ELF_HWCAP +#define ELF_HWCAP COMPAT_ELF_HWCAP +#endif + +#ifdef COMPAT_ARCH_DLINFO +#undef ARCH_DLINFO +#define ARCH_DLINFO COMPAT_ARCH_DLINFO +#endif + +#ifdef COMPAT_ELF_ET_DYN_BASE +#undef ELF_ET_DYN_BASE +#define ELF_ET_DYN_BASE COMPAT_ELF_ET_DYN_BASE +#endif + +#ifdef COMPAT_ELF_EXEC_PAGESIZE +#undef ELF_EXEC_PAGESIZE +#define ELF_EXEC_PAGESIZE COMPAT_ELF_EXEC_PAGESIZE +#endif + +#ifdef COMPAT_ELF_PLAT_INIT +#undef ELF_PLAT_INIT +#define ELF_PLAT_INIT COMPAT_ELF_PLAT_INIT +#endif + +#ifdef COMPAT_SET_PERSONALITY +#undef SET_PERSONALITY +#define SET_PERSONALITY COMPAT_SET_PERSONALITY +#endif + +#ifdef compat_start_thread +#undef start_thread +#define start_thread compat_start_thread +#endif + +#ifdef compat_arch_setup_additional_pages +#undef ARCH_HAS_SETUP_ADDITIONAL_PAGES +#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 +#undef arch_setup_additional_pages +#define arch_setup_additional_pages compat_arch_setup_additional_pages +#endif + +/* + * Rename a few of the symbols that binfmt_elf.c will define. + * These are all local so the names don't really matter, but it + * might make some debugging less confusing not to duplicate them. + */ +#define elf_format compat_elf_format +#define init_elf_binfmt init_compat_elf_binfmt +#define exit_elf_binfmt exit_compat_elf_binfmt + +/* + * We share all the actual code with the native (64-bit) version. + */ +#include "binfmt_elf.c" -- 2.39.5