linux/arch/sh/kernel/module.c
Paul Mundt 5a3abba77d sh: Tidy up the dwarf module helpers.
This enables us to build the dwarf unwinder both with modules enabled and
disabled in addition to reducing code size in the latter case. The
helpers are also consolidated, and modified to resemble the BUG module
helpers.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-10-13 13:32:19 +09:00

162 lines
4.4 KiB
C

/* Kernel module help for SH.
SHcompact version by Kaz Kojima and Paul Mundt.
SHmedia bits:
Copyright 2004 SuperH (UK) Ltd
Author: Richard Curnow
Based on the sh version, and on code from the sh64-specific parts of
modutils, originally written by Richard Curnow and Ben Gaster.
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/bug.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/unaligned.h>
#include <asm/dwarf.h>
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);
}
/* 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_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;
Elf32_Addr relocation;
uint32_t *location;
uint32_t value;
pr_debug("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);
relocation = sym->st_value + rel[i].r_addend;
#ifdef CONFIG_SUPERH64
/* For text addresses, bit2 of the st_other field indicates
* whether the symbol is SHmedia (1) or SHcompact (0). If
* SHmedia, the LSB of the symbol needs to be asserted
* for the CPU to be in SHmedia mode when it starts executing
* the branch target. */
relocation |= !!(sym->st_other & 4);
#endif
switch (ELF32_R_TYPE(rel[i].r_info)) {
case R_SH_DIR32:
value = get_unaligned(location);
value += relocation;
put_unaligned(value, location);
break;
case R_SH_REL32:
relocation = (relocation - (Elf32_Addr) location);
value = get_unaligned(location);
value += relocation;
put_unaligned(value, location);
break;
case R_SH_IMM_LOW16:
*location = (*location & ~0x3fffc00) |
((relocation & 0xffff) << 10);
break;
case R_SH_IMM_MEDLOW16:
*location = (*location & ~0x3fffc00) |
(((relocation >> 16) & 0xffff) << 10);
break;
case R_SH_IMM_LOW16_PCREL:
relocation -= (Elf32_Addr) location;
*location = (*location & ~0x3fffc00) |
((relocation & 0xffff) << 10);
break;
case R_SH_IMM_MEDLOW16_PCREL:
relocation -= (Elf32_Addr) location;
*location = (*location & ~0x3fffc00) |
(((relocation >> 16) & 0xffff) << 10);
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(Elf32_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
printk(KERN_ERR "module %s: REL RELOCATION unsupported\n",
me->name);
return -ENOEXEC;
}
int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
int ret = 0;
ret |= module_dwarf_finalize(hdr, sechdrs, me);
ret |= module_bug_finalize(hdr, sechdrs, me);
return ret;
}
void module_arch_cleanup(struct module *mod)
{
module_bug_cleanup(mod);
module_dwarf_cleanup(mod);
}