| Jonas Bonn | 5a2bbb8 | 2011-06-04 22:35:19 +0300 | [diff] [blame] | 1 | /* |
| 2 | * OpenRISC module.c |
| 3 | * |
| 4 | * Linux architectural port borrowing liberally from similar works of |
| 5 | * others. All original copyrights apply as per the original source |
| 6 | * declaration. |
| 7 | * |
| 8 | * Modifications for the OpenRISC architecture: |
| 9 | * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License |
| 13 | * as published by the Free Software Foundation; either version |
| 14 | * 2 of the License, or (at your option) any later version. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/moduleloader.h> |
| 18 | #include <linux/elf.h> |
| 19 | |
| 20 | int apply_relocate_add(Elf32_Shdr *sechdrs, |
| 21 | const char *strtab, |
| 22 | unsigned int symindex, |
| 23 | unsigned int relsec, |
| 24 | struct module *me) |
| 25 | { |
| 26 | unsigned int i; |
| 27 | Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; |
| 28 | Elf32_Sym *sym; |
| 29 | uint32_t *location; |
| 30 | uint32_t value; |
| 31 | |
| 32 | pr_debug("Applying relocate section %u to %u\n", relsec, |
| 33 | sechdrs[relsec].sh_info); |
| 34 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { |
| 35 | /* This is where to make the change */ |
| 36 | location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr |
| 37 | + rel[i].r_offset; |
| 38 | |
| 39 | /* This is the symbol it is referring to. Note that all |
| 40 | undefined symbols have been resolved. */ |
| 41 | sym = (Elf32_Sym *)sechdrs[symindex].sh_addr |
| 42 | + ELF32_R_SYM(rel[i].r_info); |
| 43 | value = sym->st_value + rel[i].r_addend; |
| 44 | |
| 45 | switch (ELF32_R_TYPE(rel[i].r_info)) { |
| 46 | case R_OR32_32: |
| 47 | *location = value; |
| 48 | break; |
| 49 | case R_OR32_CONST: |
| 50 | location = (uint16_t *)location + 1; |
| 51 | *((uint16_t *)location) = (uint16_t) (value); |
| 52 | break; |
| 53 | case R_OR32_CONSTH: |
| 54 | location = (uint16_t *)location + 1; |
| 55 | *((uint16_t *)location) = (uint16_t) (value >> 16); |
| 56 | break; |
| 57 | case R_OR32_JUMPTARG: |
| 58 | value -= (uint32_t)location; |
| 59 | value >>= 2; |
| 60 | value &= 0x03ffffff; |
| 61 | value |= *location & 0xfc000000; |
| 62 | *location = value; |
| 63 | break; |
| 64 | default: |
| 65 | pr_err("module %s: Unknown relocation: %u\n", |
| 66 | me->name, ELF32_R_TYPE(rel[i].r_info)); |
| 67 | break; |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | return 0; |
| 72 | } |