| 1 | |
| 2 | * Kernel module support for Nios II.
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| 3 | *
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| 4 | * Copyright (C) 2004 Microtronix Datacom Ltd.
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| 5 | * Written by Wentao Xu <[email protected]>
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| 6 | * Copyright (C) 2001, 2003 Rusty Russell
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| 7 | *
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| 8 | * This file is subject to the terms and conditions of the GNU General
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| 9 | * Public License. See the file COPYING in the main directory of this
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| 10 | * archive for more details.
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| 11 |
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| 12 |
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| 13 | #include <linux/moduleloader.h>
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| 14 | #include <linux/elf.h>
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| 15 | #include <linux/mm.h>
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| 16 | #include <linux/slab.h>
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| 17 | #include <linux/fs.h>
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| 18 | #include <linux/string.h>
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| 19 | #include <linux/kernel.h>
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| 20 |
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| 21 | #include <asm/cacheflush.h>
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| 22 |
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| 23 | int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
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| 24 | unsigned int symindex, unsigned int relsec,
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| 25 | struct module *mod)
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| 26 | {
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| 27 | unsigned int i;
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| 28 | Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
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| 29 |
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| 30 | pr_debug("Applying relocate section %u to %u\n", relsec,
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| 31 | sechdrs[relsec].sh_info);
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| 32 |
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| 33 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
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| 34 |
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| 35 | uint32_t word;
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| 36 | uint32_t *loc
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| 37 | = ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
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| 38 | + rela[i].r_offset);
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| 39 | |
| 40 | undefined symbols have been resolved.
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| 41 | Elf32_Sym *sym
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| 42 | = ((Elf32_Sym *)sechdrs[symindex].sh_addr
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| 43 | + ELF32_R_SYM(rela[i].r_info));
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| 44 | uint32_t v = sym->st_value + rela[i].r_addend;
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| 45 |
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| 46 | pr_debug("reltype %d 0x%x name:<%s>\n",
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| 47 | ELF32_R_TYPE(rela[i].r_info),
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| 48 | rela[i].r_offset, strtab + sym->st_name);
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| 49 |
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| 50 | switch (ELF32_R_TYPE(rela[i].r_info)) {
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| 51 | case R_NIOS2_NONE:
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| 52 | break;
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| 53 | case R_NIOS2_BFD_RELOC_32:
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| 54 | *loc += v;
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| 55 | break;
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| 56 | case R_NIOS2_PCREL16:
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| 57 | v -= (uint32_t)loc + 4;
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| 58 | if ((int32_t)v > 0x7fff ||
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| 59 | (int32_t)v < -(int32_t)0x8000) {
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| 60 | pr_err("module %s: relocation overflow\n",
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| 61 | mod->name);
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| 62 | return -ENOEXEC;
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| 63 | }
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| 64 | word = *loc;
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| 65 | *loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
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| 66 | (word & 0x3f);
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| 67 | break;
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| 68 | case R_NIOS2_CALL26:
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| 69 | if (v & 3) {
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| 70 | pr_err("module %s: dangerous relocation\n",
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| 71 | mod->name);
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| 72 | return -ENOEXEC;
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| 73 | }
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| 74 | if ((v >> 28) != ((uint32_t)loc >> 28)) {
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| 75 | pr_err("module %s: relocation overflow\n",
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| 76 | mod->name);
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| 77 | return -ENOEXEC;
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| 78 | }
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| 79 | *loc = (*loc & 0x3f) | ((v >> 2) << 6);
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| 80 | break;
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| 81 | case R_NIOS2_HI16:
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| 82 | word = *loc;
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| 83 | *loc = ((((word >> 22) << 16) |
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| 84 | ((v >> 16) & 0xffff)) << 6) | (word & 0x3f);
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| 85 | break;
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| 86 | case R_NIOS2_LO16:
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| 87 | word = *loc;
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| 88 | *loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
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| 89 | (word & 0x3f);
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| 90 | break;
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| 91 | case R_NIOS2_HIADJ16:
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| 92 | {
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| 93 | Elf32_Addr word2;
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| 94 |
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| 95 | word = *loc;
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| 96 | word2 = ((v >> 16) + ((v >> 15) & 1)) & 0xffff;
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| 97 | *loc = ((((word >> 22) << 16) | word2) << 6) |
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| 98 | (word & 0x3f);
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| 99 | }
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| 100 | break;
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| 101 |
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| 102 | default:
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| 103 | pr_err("module %s: Unknown reloc: %u\n",
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| 104 | mod->name, ELF32_R_TYPE(rela[i].r_info));
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| 105 | return -ENOEXEC;
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| 106 | }
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| 107 | }
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| 108 |
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| 109 | return 0;
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| 110 | }
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| 111 |
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| 112 | int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
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| 113 | struct module *me)
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| 114 | {
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| 115 | flush_cache_all();
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| 116 | return 0;
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| 117 | }
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