arch/x86/lib/efi/reloc_ia32.c

   1 /*
   2  * reloc_ia32.c - position independent x86 ELF shared object relocator
   3  * Copyright (C) 1999 Hewlett-Packard Co.
   4  * Contributed by David Mosberger <davidm@hpl.hp.com>.
   5  *
   6  * All rights reserved.
   7  *
   8  * SPDX-License-Identifier:     BSD-3-Clause
   9  */
  10
  11 #include <common.h>
  12 #include <efi.h>
  13 #include <elf.h>
  14 #include <asm/elf.h>
  15
  16 efi_status_t _relocate(long ldbase, Elf32_Dyn *dyn, efi_handle_t image,
  17                        struct efi_system_table *systab)
  18 {
  19         long relsz = 0, relent = 0;
  20         Elf32_Rel *rel = 0;
  21         unsigned long *addr;
  22         int i;
  23
  24         for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
  25                 switch (dyn[i].d_tag) {
  26                 case DT_REL:
  27                         rel = (Elf32_Rel *)((unsigned long)dyn[i].d_un.d_ptr +
  28                                                                 ldbase);
  29                         break;
  30
  31                 case DT_RELSZ:
  32                         relsz = dyn[i].d_un.d_val;
  33                         break;
  34
  35                 case DT_RELENT:
  36                         relent = dyn[i].d_un.d_val;
  37                         break;
  38
  39                 case DT_RELA:
  40                         break;
  41
  42                 default:
  43                         break;
  44                 }
  45         }
  46
  47         if (!rel && relent == 0)
  48                 return EFI_SUCCESS;
  49
  50         if (!rel || relent == 0)
  51                 return EFI_LOAD_ERROR;
  52
  53         while (relsz > 0) {
  54                 /* apply the relocs */
  55                 switch (ELF32_R_TYPE(rel->r_info)) {
  56                 case R_386_NONE:
  57                         break;
  58
  59                 case R_386_RELATIVE:
  60                         addr = (unsigned long *)(ldbase + rel->r_offset);
  61                         *addr += ldbase;
  62                         break;
  63
  64                 default:
  65                         break;
  66                 }
  67                 rel = (Elf32_Rel *)((char *)rel + relent);
  68                 relsz -= relent;
  69         }
  70
  71         return EFI_SUCCESS;
  72 }