1 // SPDX-License-Identifier: BSD-3-Clause 2 /* 3 * reloc_x86_64.c - position independent x86_64 ELF shared object relocator 4 * Copyright (C) 1999 Hewlett-Packard Co. 5 * Contributed by David Mosberger <davidm@hpl.hp.com>. 6 * Copyright (C) 2005 Intel Co. 7 * Contributed by Fenghua Yu <fenghua.yu@intel.com>. 8 * 9 * All rights reserved. 10 */ 11 12 #include <common.h> 13 #include <efi.h> 14 #include <elf.h> 15 #include <asm/elf.h> 16 17 efi_status_t EFIAPI _relocate(long ldbase, Elf64_Dyn *dyn) 18 { 19 long relsz = 0, relent = 0; 20 Elf64_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_RELA: 27 rel = (Elf64_Rel *) 28 ((unsigned long)dyn[i].d_un.d_ptr + ldbase); 29 break; 30 case DT_RELASZ: 31 relsz = dyn[i].d_un.d_val; 32 break; 33 case DT_RELAENT: 34 relent = dyn[i].d_un.d_val; 35 break; 36 default: 37 break; 38 } 39 } 40 41 if (!rel && relent == 0) 42 return EFI_SUCCESS; 43 44 if (!rel || relent == 0) 45 return EFI_LOAD_ERROR; 46 47 while (relsz > 0) { 48 /* apply the relocs */ 49 switch (ELF64_R_TYPE(rel->r_info)) { 50 case R_X86_64_NONE: 51 break; 52 case R_X86_64_RELATIVE: 53 addr = (unsigned long *)(ldbase + rel->r_offset); 54 *addr += ldbase; 55 break; 56 default: 57 break; 58 } 59 rel = (Elf64_Rel *)((char *)rel + relent); 60 relsz -= relent; 61 } 62 63 return EFI_SUCCESS; 64 } 65