1 /* Kernel module help for i386.
2 Copyright (C) 2001 Rusty Russell.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18 #include <linux/moduleloader.h>
19 #include <linux/elf.h>
20 #include <linux/vmalloc.h>
21 #include <linux/fs.h>
22 #include <linux/string.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25
26 #if 0
27 #define DEBUGP printk
28 #else
29 #define DEBUGP(fmt , ...)
30 #endif
31
32 #ifdef CONFIG_ETRAX_KMALLOCED_MODULES
module_alloc(unsigned long size)33 void *module_alloc(unsigned long size)
34 {
35 if (size == 0)
36 return NULL;
37 return kmalloc(size, GFP_KERNEL);
38 }
39
40 /* Free memory returned from module_alloc */
module_free(struct module * mod,void * module_region)41 void module_free(struct module *mod, void *module_region)
42 {
43 kfree(module_region);
44 }
45 #endif
46
apply_relocate_add(Elf32_Shdr * sechdrs,const char * strtab,unsigned int symindex,unsigned int relsec,struct module * me)47 int apply_relocate_add(Elf32_Shdr *sechdrs,
48 const char *strtab,
49 unsigned int symindex,
50 unsigned int relsec,
51 struct module *me)
52 {
53 unsigned int i;
54 Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
55
56 DEBUGP ("Applying add relocate section %u to %u\n", relsec,
57 sechdrs[relsec].sh_info);
58
59 for (i = 0; i < sechdrs[relsec].sh_size / sizeof (*rela); i++) {
60 /* This is where to make the change */
61 uint32_t *loc
62 = ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
63 + rela[i].r_offset);
64 /* This is the symbol it is referring to. Note that all
65 undefined symbols have been resolved. */
66 Elf32_Sym *sym
67 = ((Elf32_Sym *)sechdrs[symindex].sh_addr
68 + ELF32_R_SYM (rela[i].r_info));
69 switch (ELF32_R_TYPE(rela[i].r_info)) {
70 case R_CRIS_32:
71 *loc = sym->st_value + rela[i].r_addend;
72 break;
73 case R_CRIS_32_PCREL:
74 *loc = sym->st_value - (unsigned)loc + rela[i].r_addend - 4;
75 break;
76 default:
77 printk(KERN_ERR "module %s: Unknown relocation: %u\n",
78 me->name, ELF32_R_TYPE(rela[i].r_info));
79 return -ENOEXEC;
80 }
81 }
82
83 return 0;
84 }
85