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/*
* linux/arch/arm/kernel/module.c
*
* Copyright (C) 2002 Russell King.
* Modified for nommu by Hyok S. Choi
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Module allocation method suggested by Andi Kleen.
*/
#include <linux/module.h>
#include <linux/moduleloader.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/unwind.h>
#ifdef CONFIG_XIP_KERNEL
/*
* The XIP kernel text is mapped in the module area for modules and
* some other stuff to work without any indirect relocations.
* MODULES_VADDR is redefined here and not in asm/memory.h to avoid
* recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
*/
#undef MODULES_VADDR
#define MODULES_VADDR (((unsigned long)_etext + ~PGDIR_MASK) & PGDIR_MASK)
#endif
#ifdef CONFIG_MMU
void *module_alloc(unsigned long size)
{
struct vm_struct *area;
size = PAGE_ALIGN(size);
if (!size)
return NULL;
area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
if (!area)
return NULL;
return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
}
#else /* CONFIG_MMU */
void *module_alloc(unsigned long size)
{
return size == 0 ? NULL : vmalloc(size);
}
#endif /* !CONFIG_MMU */
void module_free(struct module *module, void *region)
{
vfree(region);
}
int module_frob_arch_sections(Elf_Ehdr *hdr,
Elf_Shdr *sechdrs,
char *secstrings,
struct module *mod)
{
#ifdef CONFIG_ARM_UNWIND
Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
for (s = sechdrs; s < sechdrs_end; s++) {
if (strcmp(".ARM.exidx.init.text", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_init = s;
else if (strcmp(".ARM.exidx.devinit.text", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_devinit = s;
else if (strcmp(".ARM.exidx", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_core = s;
else if (strcmp(".init.text", secstrings + s->sh_name) == 0)
mod->arch.sec_init_text = s;
else if (strcmp(".devinit.text", secstrings + s->sh_name) == 0)
mod->arch.sec_devinit_text = s;
else if (strcmp(".text", secstrings + s->sh_name) == 0)
mod->arch.sec_core_text = s;
}
#endif
return 0;
}
int
apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
unsigned int relindex, struct module *module)
{
Elf32_Shdr *symsec = sechdrs + symindex;
Elf32_Shdr *relsec = sechdrs + relindex;
Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
Elf32_Rel *rel = (void *)relsec->sh_addr;
unsigned int i;
for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
unsigned long loc;
Elf32_Sym *sym;
s32 offset;
offset = ELF32_R_SYM(rel->r_info);
if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
printk(KERN_ERR "%s: bad relocation, section %d reloc %d\n",
module->name, relindex, i);
return -ENOEXEC;
}
sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
printk(KERN_ERR "%s: out of bounds relocation, "
"section %d reloc %d offset %d size %d\n",
module->name, relindex, i, rel->r_offset,
dstsec->sh_size);
return -ENOEXEC;
}
loc = dstsec->sh_addr + rel->r_offset;
switch (ELF32_R_TYPE(rel->r_info)) {
case R_ARM_NONE:
/* ignore */
break;
case R_ARM_ABS32:
*(u32 *)loc += sym->st_value;
break;
case R_ARM_PC24:
case R_ARM_CALL:
case R_ARM_JUMP24:
offset = (*(u32 *)loc & 0x00ffffff) << 2;
if (offset & 0x02000000)
offset -= 0x04000000;
offset += sym->st_value - loc;
if (offset & 3 ||
offset <= (s32)0xfe000000 ||
offset >= (s32)0x02000000) {
printk(KERN_ERR
"%s: relocation out of range, section "
"%d reloc %d sym '%s'\n", module->name,
relindex, i, strtab + sym->st_name);
return -ENOEXEC;
}
offset >>= 2;
*(u32 *)loc &= 0xff000000;
*(u32 *)loc |= offset & 0x00ffffff;
break;
case R_ARM_V4BX:
/* Preserve Rm and the condition code. Alter
* other bits to re-code instruction as
* MOV PC,Rm.
*/
*(u32 *)loc &= 0xf000000f;
*(u32 *)loc |= 0x01a0f000;
break;
case R_ARM_PREL31:
offset = *(u32 *)loc + sym->st_value - loc;
*(u32 *)loc = offset & 0x7fffffff;
break;
default:
printk(KERN_ERR "%s: unknown relocation: %u\n",
module->name, ELF32_R_TYPE(rel->r_info));
return -ENOEXEC;
}
}
return 0;
}
int
apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
unsigned int symindex, unsigned int relsec, struct module *module)
{
printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
module->name);
return -ENOEXEC;
}
#ifdef CONFIG_ARM_UNWIND
static void register_unwind_tables(struct module *mod)
{
if (mod->arch.unw_sec_init && mod->arch.sec_init_text)
mod->arch.unwind_init =
unwind_table_add(mod->arch.unw_sec_init->sh_addr,
mod->arch.unw_sec_init->sh_size,
mod->arch.sec_init_text->sh_addr,
mod->arch.sec_init_text->sh_size);
if (mod->arch.unw_sec_devinit && mod->arch.sec_devinit_text)
mod->arch.unwind_devinit =
unwind_table_add(mod->arch.unw_sec_devinit->sh_addr,
mod->arch.unw_sec_devinit->sh_size,
mod->arch.sec_devinit_text->sh_addr,
mod->arch.sec_devinit_text->sh_size);
if (mod->arch.unw_sec_core && mod->arch.sec_core_text)
mod->arch.unwind_core =
unwind_table_add(mod->arch.unw_sec_core->sh_addr,
mod->arch.unw_sec_core->sh_size,
mod->arch.sec_core_text->sh_addr,
mod->arch.sec_core_text->sh_size);
}
static void unregister_unwind_tables(struct module *mod)
{
unwind_table_del(mod->arch.unwind_init);
unwind_table_del(mod->arch.unwind_devinit);
unwind_table_del(mod->arch.unwind_core);
}
#else
static inline void register_unwind_tables(struct module *mod) { }
static inline void unregister_unwind_tables(struct module *mod) { }
#endif
int
module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
struct module *module)
{
register_unwind_tables(module);
return 0;
}
void
module_arch_cleanup(struct module *mod)
{
unregister_unwind_tables(mod);
}
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