aboutsummaryrefslogtreecommitdiff
path: root/arch/sh/kernel/module.c
blob: ae0be697a89e4b220f527a2bdb34f4da7ec7d318 (plain)
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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*  Kernel module help for SH.

    SHcompact version by Kaz Kojima and Paul Mundt.

    SHmedia bits:

	Copyright 2004 SuperH (UK) Ltd
	Author: Richard Curnow

	Based on the sh version, and on code from the sh64-specific parts of
	modutils, originally written by Richard Curnow and Ben Gaster.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/bug.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/unaligned.h>
#include <asm/dwarf.h>

void *module_alloc(unsigned long size)
{
	if (size == 0)
		return NULL;

	return vmalloc_exec(size);
}


/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
	vfree(module_region);
}

/* We don't need anything special. */
int module_frob_arch_sections(Elf_Ehdr *hdr,
			      Elf_Shdr *sechdrs,
			      char *secstrings,
			      struct module *mod)
{
	return 0;
}

int apply_relocate_add(Elf32_Shdr *sechdrs,
		   const char *strtab,
		   unsigned int symindex,
		   unsigned int relsec,
		   struct module *me)
{
	unsigned int i;
	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
	Elf32_Sym *sym;
	Elf32_Addr relocation;
	uint32_t *location;
	uint32_t value;

	pr_debug("Applying relocate section %u to %u\n", relsec,
		 sechdrs[relsec].sh_info);
	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
		/* This is where to make the change */
		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
			+ rel[i].r_offset;
		/* This is the symbol it is referring to.  Note that all
		   undefined symbols have been resolved.  */
		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
			+ ELF32_R_SYM(rel[i].r_info);
		relocation = sym->st_value + rel[i].r_addend;

#ifdef CONFIG_SUPERH64
		/* For text addresses, bit2 of the st_other field indicates
		 * whether the symbol is SHmedia (1) or SHcompact (0).  If
		 * SHmedia, the LSB of the symbol needs to be asserted
		 * for the CPU to be in SHmedia mode when it starts executing
		 * the branch target. */
		relocation |= !!(sym->st_other & 4);
#endif

		switch (ELF32_R_TYPE(rel[i].r_info)) {
		case R_SH_DIR32:
			value = get_unaligned(location);
			value += relocation;
			put_unaligned(value, location);
			break;
		case R_SH_REL32:
			relocation = (relocation - (Elf32_Addr) location);
			value = get_unaligned(location);
			value += relocation;
			put_unaligned(value, location);
			break;
		case R_SH_IMM_LOW16:
			*location = (*location & ~0x3fffc00) |
				((relocation & 0xffff) << 10);
			break;
		case R_SH_IMM_MEDLOW16:
			*location = (*location & ~0x3fffc00) |
				(((relocation >> 16) & 0xffff) << 10);
			break;
		case R_SH_IMM_LOW16_PCREL:
			relocation -= (Elf32_Addr) location;
			*location = (*location & ~0x3fffc00) |
				((relocation & 0xffff) << 10);
			break;
		case R_SH_IMM_MEDLOW16_PCREL:
			relocation -= (Elf32_Addr) location;
			*location = (*location & ~0x3fffc00) |
				(((relocation >> 16) & 0xffff) << 10);
			break;
		default:
			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
			       me->name, ELF32_R_TYPE(rel[i].r_info));
			return -ENOEXEC;
		}
	}
	return 0;
}

int apply_relocate(Elf32_Shdr *sechdrs,
		       const char *strtab,
		       unsigned int symindex,
		       unsigned int relsec,
		       struct module *me)
{
	printk(KERN_ERR "module %s: REL RELOCATION unsupported\n",
	       me->name);
	return -ENOEXEC;
}

int module_finalize(const Elf_Ehdr *hdr,
		    const Elf_Shdr *sechdrs,
		    struct module *me)
{
	int ret = 0;

	ret |= module_dwarf_finalize(hdr, sechdrs, me);

	return ret;
}

void module_arch_cleanup(struct module *mod)
{
	module_dwarf_cleanup(mod);
}