arch/cris/kernel/module.c

   1 /*  Kernel module help for i386.
   2     Copyright (C) 2001 Rusty Russell.
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17 */
  18 #include <linux/moduleloader.h>
  19 #include <linux/elf.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/fs.h>
  22 #include <linux/string.h>
  23 #include <linux/kernel.h>
  24 #include <linux/slab.h>
  25
  26 #if 0
  27 #define DEBUGP printk
  28 #else
  29 #define DEBUGP(fmt , ...)
  30 #endif
  31
  32 #ifdef CONFIG_ETRAX_KMALLOCED_MODULES
  33 void *module_alloc(unsigned long size)
  34 {
  35         if (size == 0)
  36                 return NULL;
  37         return kmalloc(size, GFP_KERNEL);
  38 }
  39
  40 /* Free memory returned from module_alloc */
  41 void module_free(struct module *mod, void *module_region)
  42 {
  43         kfree(module_region);
  44 }
  45 #endif
  46
  47 int apply_relocate_add(Elf32_Shdr *sechdrs,
  48                        const char *strtab,
  49                        unsigned int symindex,
  50                        unsigned int relsec,
  51                        struct module *me)
  52 {
  53         unsigned int i;
  54         Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
  55
  56         DEBUGP ("Applying add relocate section %u to %u\n", relsec,
  57                 sechdrs[relsec].sh_info);
  58
  59         for (i = 0; i < sechdrs[relsec].sh_size / sizeof (*rela); i++) {
  60                 /* This is where to make the change */
  61                 uint32_t *loc
  62                         = ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
  63                            + rela[i].r_offset);
  64                 /* This is the symbol it is referring to.  Note that all
  65                    undefined symbols have been resolved.  */
  66                 Elf32_Sym *sym
  67                         = ((Elf32_Sym *)sechdrs[symindex].sh_addr
  68                            + ELF32_R_SYM (rela[i].r_info));
  69                 switch (ELF32_R_TYPE(rela[i].r_info)) {
  70                 case R_CRIS_32:
  71                         *loc = sym->st_value + rela[i].r_addend;
  72                         break;
  73                 case R_CRIS_32_PCREL:
  74                         *loc = sym->st_value - (unsigned)loc + rela[i].r_addend - 4;
  75                          break;
  76                 default:
  77                         printk(KERN_ERR "module %s: Unknown relocation: %u\n",
  78                                me->name, ELF32_R_TYPE(rela[i].r_info));
  79                         return -ENOEXEC;
  80                 }
  81         }
  82
  83         return 0;
  84 }