1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/*
* Kernel module support for Nios II.
*
* Copyright (C) 2004 Microtronix Datacom Ltd.
* Written by Wentao Xu <xuwentao@microtronix.com>
* Copyright (C) 2001, 2003 Rusty Russell
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*/
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/cacheflush.h>
/*
* Modules should NOT be allocated with kmalloc for (obvious) reasons.
* But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
* from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
* addresses in 0xc0000000)
*/
void *module_alloc(unsigned long size)
{
if (size == 0)
return NULL;
return kmalloc(size, GFP_KERNEL);
}
/* Free memory returned from module_alloc */
void module_memfree(void *module_region)
{
kfree(module_region);
}
int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
unsigned int symindex, unsigned int relsec,
struct module *mod)
{
unsigned int i;
Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
pr_debug("Applying relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
/* This is where to make the change */
uint32_t word;
uint32_t *loc
= ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rela[i].r_offset);
/* This is the symbol it is referring to. Note that all
undefined symbols have been resolved. */
Elf32_Sym *sym
= ((Elf32_Sym *)sechdrs[symindex].sh_addr
+ ELF32_R_SYM(rela[i].r_info));
uint32_t v = sym->st_value + rela[i].r_addend;
pr_debug("reltype %d 0x%x name:<%s>\n",
ELF32_R_TYPE(rela[i].r_info),
rela[i].r_offset, strtab + sym->st_name);
switch (ELF32_R_TYPE(rela[i].r_info)) {
case R_NIOS2_NONE:
break;
case R_NIOS2_BFD_RELOC_32:
*loc += v;
break;
case R_NIOS2_PCREL16:
v -= (uint32_t)loc + 4;
if ((int32_t)v > 0x7fff ||
(int32_t)v < -(int32_t)0x8000) {
pr_err("module %s: relocation overflow\n",
mod->name);
return -ENOEXEC;
}
word = *loc;
*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
(word & 0x3f);
break;
case R_NIOS2_CALL26:
if (v & 3) {
pr_err("module %s: dangerous relocation\n",
mod->name);
return -ENOEXEC;
}
if ((v >> 28) != ((uint32_t)loc >> 28)) {
pr_err("module %s: relocation overflow\n",
mod->name);
return -ENOEXEC;
}
*loc = (*loc & 0x3f) | ((v >> 2) << 6);
break;
case R_NIOS2_HI16:
word = *loc;
*loc = ((((word >> 22) << 16) |
((v >> 16) & 0xffff)) << 6) | (word & 0x3f);
break;
case R_NIOS2_LO16:
word = *loc;
*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
(word & 0x3f);
break;
case R_NIOS2_HIADJ16:
{
Elf32_Addr word2;
word = *loc;
word2 = ((v >> 16) + ((v >> 15) & 1)) & 0xffff;
*loc = ((((word >> 22) << 16) | word2) << 6) |
(word & 0x3f);
}
break;
default:
pr_err("module %s: Unknown reloc: %u\n",
mod->name, ELF32_R_TYPE(rela[i].r_info));
return -ENOEXEC;
}
}
return 0;
}
int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
struct module *me)
{
flush_cache_all();
return 0;
}
|
