/* Kernel module help for i386.
Copyright (C) 2001 Rusty Russell.
This program 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 2 of the License, or
(at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt...)
#endif
void *module_alloc(unsigned long size)
{
if (size == 0)
return NULL;
return vmalloc_exec(size);
}
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
vfree(module_region);
/* FIXME: If module_region == mod->init_region, trim exception
table entries. */
}
/* We don't need anything special. */
int module_frob_arch_sections(Elf_Ehdr *hdr,
Elf_Shdr *sechdrs,
char *secstrings,
struct module *mod)
{
return 0;
}
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_386_32:
/* We add the value into the location given */
*location += sym->st_value;
break;
case R_386_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)
{
printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
me->name);
return -ENOEXEC;
}
int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
const Elf_Shdr *s, *text = NULL, *alt = NULL, *locks = NULL;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
if (!strcmp(".text", secstrings + s->sh_name))
text = s;
if (!strcmp(".altinstructions", secstrings + s->sh_name))
alt = s;
if (!strcmp(".smp_locks", secstrings + s->sh_name))
locks= s;
}
if (alt) {
/* patch .altinstructions */
void *aseg = (void *)alt->sh_addr;
apply_alternatives(aseg, aseg + alt->sh_size);
}
if (locks && text) {
void *lseg = (void *)locks->sh_addr;
void *tseg = (void *)text->sh_addr;
alternatives_smp_module_add(me, me->name,
lseg, lseg + locks->sh_size,
tseg, tseg + text->sh_size);
}
return 0;
}
void module_arch_cleanup(struct module *mod)
{
alternatives_smp_module_del(mod);
}
