Logo Search packages:      
Sourcecode: linux-2.6 version File versions

module.c

/*
 *  linux/arch/arm/kernel/module.c
 *
 *  Copyright (C) 2002 Russell King.
 *
 * 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/elf.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>

#include <asm/pgtable.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.
 * MODULE_START is redefined here and not in asm/memory.h to avoid
 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
 */
extern void _etext;
#undef MODULE_START
#define MODULE_START    (((unsigned long)&_etext + ~PGDIR_MASK) & PGDIR_MASK)
#endif

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, MODULE_START, MODULE_END);
      if (!area)
            return NULL;

      return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL);
}

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)
{
      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_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)0xfc000000 ||
                      offset >= (s32)0x04000000) {
                        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;

            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;
}

int
module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
            struct module *module)
{
      return 0;
}

void
module_arch_cleanup(struct module *mod)
{
}

Generated by  Doxygen 1.6.0   Back to index