elf32_machdep.c revision 78342 
1/*-
2 * Copyright 1996-1998 John D. Polstra.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: head/sys/powerpc/powerpc/elf_machdep.c 78342 2001-06-16 07:14:07Z benno $
26 */
27
28#include <sys/param.h>
29#include <sys/kernel.h>
30#include <sys/systm.h>
31#include <sys/malloc.h>
32#include <sys/proc.h>
33#include <sys/namei.h>
34#include <sys/fcntl.h>
35#include <sys/vnode.h>
36#include <sys/linker.h>
37#include <machine/elf.h>
38
39/* Process one elf relocation with addend. */
40int
41elf_reloc(linker_file_t lf, const void *data, int type, const char *sym)
42{
43	Elf_Addr relocbase = (Elf_Addr) lf->address;
44	Elf_Addr *where;
45	Elf_Addr addr;
46	Elf_Addr addend;
47	Elf_Word rtype;
48	const Elf_Rel *rel;
49	const Elf_Rela *rela;
50
51	switch (type) {
52	case ELF_RELOC_REL:
53		rel = (const Elf_Rel *)data;
54		where = (Elf_Addr *) (relocbase + rel->r_offset);
55		addend = *where;
56		rtype = ELF_R_TYPE(rel->r_info);
57		break;
58	case ELF_RELOC_RELA:
59		rela = (const Elf_Rela *)data;
60		where = (Elf_Addr *) (relocbase + rela->r_offset);
61		addend = rela->r_addend;
62		rtype = ELF_R_TYPE(rela->r_info);
63		break;
64	default:
65		panic("elf_reloc: unknown relocation mode %d\n", type);
66	}
67
68	switch (rtype) {
69
70		case R_PPC_NONE:
71			break;
72
73		case R_PPC_GLOB_DAT:
74			addr = (Elf_Addr)
75				linker_file_lookup_symbol(lf, sym, 1);
76			if (addr == NULL)
77				return -1;
78                        addr += addend;
79			if (*where != addr)
80				*where = addr;
81			break;
82
83		case R_PPC_JMP_SLOT:
84			/* No point in lazy binding for kernel modules. */
85			addr = (Elf_Addr)
86				linker_file_lookup_symbol(lf, sym, 1);
87			if (addr == NULL)
88				return -1;
89			if (*where != addr)
90				*where = addr;
91			break;
92
93		case R_PPC_RELATIVE:
94			addr = relocbase + addend + *where;
95			if (*where != addr)
96				*where = addr;
97			break;
98
99		case R_PPC_COPY:
100			/*
101			 * There shouldn't be copy relocations in kernel
102			 * objects.
103			 */
104			printf("kldload: unexpected R_COPY relocation\n");
105			return -1;
106
107		default:
108			printf("kldload: unexpected relocation type %d\n",
109			       (int) rtype);
110			return -1;
111	}
112	return(0);
113}
114