David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* Kernel module help for SH. |
| 3 | |
| 4 | SHcompact version by Kaz Kojima and Paul Mundt. |
| 5 | |
| 6 | SHmedia bits: |
| 7 | |
| 8 | Copyright 2004 SuperH (UK) Ltd |
| 9 | Author: Richard Curnow |
| 10 | |
| 11 | Based on the sh version, and on code from the sh64-specific parts of |
| 12 | modutils, originally written by Richard Curnow and Ben Gaster. |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 13 | */ |
| 14 | #include <linux/moduleloader.h> |
| 15 | #include <linux/elf.h> |
| 16 | #include <linux/vmalloc.h> |
| 17 | #include <linux/bug.h> |
| 18 | #include <linux/fs.h> |
| 19 | #include <linux/string.h> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <asm/unaligned.h> |
| 22 | #include <asm/dwarf.h> |
| 23 | |
| 24 | int apply_relocate_add(Elf32_Shdr *sechdrs, |
| 25 | const char *strtab, |
| 26 | unsigned int symindex, |
| 27 | unsigned int relsec, |
| 28 | struct module *me) |
| 29 | { |
| 30 | unsigned int i; |
| 31 | Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; |
| 32 | Elf32_Sym *sym; |
| 33 | Elf32_Addr relocation; |
| 34 | uint32_t *location; |
| 35 | uint32_t value; |
| 36 | |
| 37 | pr_debug("Applying relocate section %u to %u\n", relsec, |
| 38 | sechdrs[relsec].sh_info); |
| 39 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { |
| 40 | /* This is where to make the change */ |
| 41 | location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr |
| 42 | + rel[i].r_offset; |
| 43 | /* This is the symbol it is referring to. Note that all |
| 44 | undefined symbols have been resolved. */ |
| 45 | sym = (Elf32_Sym *)sechdrs[symindex].sh_addr |
| 46 | + ELF32_R_SYM(rel[i].r_info); |
| 47 | relocation = sym->st_value + rel[i].r_addend; |
| 48 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 49 | switch (ELF32_R_TYPE(rel[i].r_info)) { |
| 50 | case R_SH_NONE: |
| 51 | break; |
| 52 | case R_SH_DIR32: |
| 53 | value = get_unaligned(location); |
| 54 | value += relocation; |
| 55 | put_unaligned(value, location); |
| 56 | break; |
| 57 | case R_SH_REL32: |
| 58 | relocation = (relocation - (Elf32_Addr) location); |
| 59 | value = get_unaligned(location); |
| 60 | value += relocation; |
| 61 | put_unaligned(value, location); |
| 62 | break; |
| 63 | case R_SH_IMM_LOW16: |
| 64 | *location = (*location & ~0x3fffc00) | |
| 65 | ((relocation & 0xffff) << 10); |
| 66 | break; |
| 67 | case R_SH_IMM_MEDLOW16: |
| 68 | *location = (*location & ~0x3fffc00) | |
| 69 | (((relocation >> 16) & 0xffff) << 10); |
| 70 | break; |
| 71 | case R_SH_IMM_LOW16_PCREL: |
| 72 | relocation -= (Elf32_Addr) location; |
| 73 | *location = (*location & ~0x3fffc00) | |
| 74 | ((relocation & 0xffff) << 10); |
| 75 | break; |
| 76 | case R_SH_IMM_MEDLOW16_PCREL: |
| 77 | relocation -= (Elf32_Addr) location; |
| 78 | *location = (*location & ~0x3fffc00) | |
| 79 | (((relocation >> 16) & 0xffff) << 10); |
| 80 | break; |
| 81 | default: |
| 82 | printk(KERN_ERR "module %s: Unknown relocation: %u\n", |
| 83 | me->name, ELF32_R_TYPE(rel[i].r_info)); |
| 84 | return -ENOEXEC; |
| 85 | } |
| 86 | } |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | int module_finalize(const Elf_Ehdr *hdr, |
| 91 | const Elf_Shdr *sechdrs, |
| 92 | struct module *me) |
| 93 | { |
| 94 | int ret = 0; |
| 95 | |
| 96 | ret |= module_dwarf_finalize(hdr, sechdrs, me); |
| 97 | |
| 98 | return ret; |
| 99 | } |
| 100 | |
| 101 | void module_arch_cleanup(struct module *mod) |
| 102 | { |
| 103 | module_dwarf_cleanup(mod); |
| 104 | } |