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/*
* Copyright (c) 2008 Carsten Schlote <c.schlote@konzeptpark.de>
* See file CREDITS for list of people who contributed to this project.
*
* This file is part of barebox.
*
* barebox is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* barebox is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with barebox. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file
* Moduleloader Subsystem
*
* These relocation stubs are taken from Linux 2.6.10 They are used by the
* higher level ELF loader code to place ELF files to arbitrary addresses.
*/
#include <common.h>
#include <elf.h>
#include <module.h>
#include <errno.h>
int apply_relocate(Elf32_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
unsigned int i;
Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr;
Elf32_Sym *sym;
uint32_t *location;
DEBUGP("Applying relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rel[i].r_offset;
/* This is the symbol it is referring to. Note that all
undefined symbols have been resolved. */
sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+ ELF32_R_SYM(rel[i].r_info);
switch (ELF32_R_TYPE(rel[i].r_info)) {
case R_68K_32:
/* We add the value into the location given */
*location += sym->st_value;
break;
case R_68K_PC32:
/* Add the value, subtract its postition */
*location += sym->st_value - (uint32_t)location;
break;
default:
printk(KERN_ERR "module %s: Unknown relocation: %u\n",
me->name, ELF32_R_TYPE(rel[i].r_info));
return -ENOEXEC;
}
}
return 0;
}
int apply_relocate_add(Elf32_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
unsigned int i;
Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
Elf32_Sym *sym;
uint32_t *location;
DEBUGP("Applying relocate_add section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rel[i].r_offset;
/* This is the symbol it is referring to. Note that all
undefined symbols have been resolved. */
sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+ ELF32_R_SYM(rel[i].r_info);
switch (ELF32_R_TYPE(rel[i].r_info)) {
case R_68K_32:
/* We add the value into the location given */
*location = rel[i].r_addend + sym->st_value;
break;
case R_68K_PC32:
/* Add the value, subtract its postition */
*location = rel[i].r_addend + sym->st_value - (uint32_t)location;
break;
default:
printk(KERN_ERR "module %s: Unknown relocation: %u\n",
me->name, ELF32_R_TYPE(rel[i].r_info));
return -ENOEXEC;
}
}
return 0;
}
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