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 (at) hpl.hp.com>. 6 * Copyright (C) 2005 Intel Co. 7 * Contributed by Fenghua Yu <fenghua.yu (at) 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 _relocate(long ldbase, Elf64_Dyn *dyn, efi_handle_t image, 18 struct efi_system_table *systab) 19 { 20 long relsz = 0, relent = 0; 21 Elf64_Rel *rel = 0; 22 unsigned long *addr; 23 int i; 24 25 for (i = 0; dyn[i].d_tag != DT_NULL; ++i) { 26 switch (dyn[i].d_tag) { 27 case DT_RELA: 28 rel = (Elf64_Rel *) 29 ((unsigned long)dyn[i].d_un.d_ptr + ldbase); 30 break; 31 case DT_RELASZ: 32 relsz = dyn[i].d_un.d_val; 33 break; 34 case DT_RELAENT: 35 relent = dyn[i].d_un.d_val; 36 break; 37 default: 38 break; 39 } 40 } 41 42 if (!rel && relent == 0) 43 return EFI_SUCCESS; 44 45 if (!rel || relent == 0) 46 return EFI_LOAD_ERROR; 47 48 while (relsz > 0) { 49 /* apply the relocs */ 50 switch (ELF64_R_TYPE(rel->r_info)) { 51 case R_X86_64_NONE: 52 break; 53 case R_X86_64_RELATIVE: 54 addr = (unsigned long *)(ldbase + rel->r_offset); 55 *addr += ldbase; 56 break; 57 default: 58 break; 59 } 60 rel = (Elf64_Rel *)((char *)rel + relent); 61 relsz -= relent; 62 } 63 64 return EFI_SUCCESS; 65 } 66