1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file COPYING in the main directory of this archive
4 * for more details.
5 */
6
7#include <linux/moduleloader.h>
8#include <linux/elf.h>
9#include <linux/vmalloc.h>
10#include <linux/fs.h>
11#include <linux/string.h>
12#include <linux/kernel.h>
13
14#if 0
15#define DEBUGP(fmt, ...) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
16#else
17#define DEBUGP(fmt, ...) no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
18#endif
19
20#ifdef CONFIG_MODULES
21
22int apply_relocate(Elf32_Shdr *sechdrs,
23 const char *strtab,
24 unsigned int symindex,
25 unsigned int relsec,
26 struct module *me)
27{
28 unsigned int i;
29 Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr;
30 Elf32_Sym *sym;
31 uint32_t *location;
32
33 DEBUGP("Applying relocate section %u to %u\n", relsec,
34 sechdrs[relsec].sh_info);
35 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
36 /* This is where to make the change */
37 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
38 + rel[i].r_offset;
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
44 switch (ELF32_R_TYPE(rel[i].r_info)) {
45 case R_68K_32:
46 /* We add the value into the location given */
47 *location += sym->st_value;
48 break;
49 case R_68K_PC32:
50 /* Add the value, subtract its position */
51 *location += sym->st_value - (uint32_t)location;
52 break;
53 default:
54 pr_err("module %s: Unknown relocation: %u\n", me->name,
55 ELF32_R_TYPE(rel[i].r_info));
56 return -ENOEXEC;
57 }
58 }
59 return 0;
60}
61
62int apply_relocate_add(Elf32_Shdr *sechdrs,
63 const char *strtab,
64 unsigned int symindex,
65 unsigned int relsec,
66 struct module *me)
67{
68 unsigned int i;
69 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
70 Elf32_Sym *sym;
71 uint32_t *location;
72
73 DEBUGP("Applying relocate_add section %u to %u\n", relsec,
74 sechdrs[relsec].sh_info);
75 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
76 /* This is where to make the change */
77 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
78 + rel[i].r_offset;
79 /* This is the symbol it is referring to. Note that all
80 undefined symbols have been resolved. */
81 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
82 + ELF32_R_SYM(rel[i].r_info);
83
84 switch (ELF32_R_TYPE(rel[i].r_info)) {
85 case R_68K_32:
86 /* We add the value into the location given */
87 *location = rel[i].r_addend + sym->st_value;
88 break;
89 case R_68K_PC32:
90 /* Add the value, subtract its position */
91 *location = rel[i].r_addend + sym->st_value - (uint32_t)location;
92 break;
93 default:
94 pr_err("module %s: Unknown relocation: %u\n", me->name,
95 ELF32_R_TYPE(rel[i].r_info));
96 return -ENOEXEC;
97 }
98 }
99 return 0;
100}
101
102int module_finalize(const Elf_Ehdr *hdr,
103 const Elf_Shdr *sechdrs,
104 struct module *mod)
105{
106 module_fixup(mod, mod->arch.fixup_start, mod->arch.fixup_end);
107 return 0;
108}
109
110#endif /* CONFIG_MODULES */
111
112void module_fixup(struct module *mod, struct m68k_fixup_info *start,
113 struct m68k_fixup_info *end)
114{
115#ifdef CONFIG_MMU
116 struct m68k_fixup_info *fixup;
117
118 for (fixup = start; fixup < end; fixup++) {
119 switch (fixup->type) {
120 case m68k_fixup_memoffset:
121 *(u32 *)fixup->addr = m68k_memoffset;
122 break;
123 case m68k_fixup_vnode_shift:
124 *(u16 *)fixup->addr += m68k_virt_to_node_shift;
125 break;
126 }
127 }
128#endif
129}
130

source code of linux/arch/m68k/kernel/module.c