Commit | Line | Data |
---|---|---|
1da177e4 LT |
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> | |
91768d6c | 24 | #include <linux/bug.h> |
1da177e4 LT |
25 | |
26 | #if 0 | |
27 | #define DEBUGP printk | |
28 | #else | |
29 | #define DEBUGP(fmt...) | |
30 | #endif | |
31 | ||
32 | void *module_alloc(unsigned long size) | |
33 | { | |
34 | if (size == 0) | |
35 | return NULL; | |
36 | return vmalloc_exec(size); | |
37 | } | |
38 | ||
39 | ||
40 | /* Free memory returned from module_alloc */ | |
41 | void module_free(struct module *mod, void *module_region) | |
42 | { | |
43 | vfree(module_region); | |
44 | /* FIXME: If module_region == mod->init_region, trim exception | |
45 | table entries. */ | |
46 | } | |
47 | ||
48 | /* We don't need anything special. */ | |
49 | int module_frob_arch_sections(Elf_Ehdr *hdr, | |
50 | Elf_Shdr *sechdrs, | |
51 | char *secstrings, | |
52 | struct module *mod) | |
53 | { | |
54 | return 0; | |
55 | } | |
56 | ||
57 | int apply_relocate(Elf32_Shdr *sechdrs, | |
58 | const char *strtab, | |
59 | unsigned int symindex, | |
60 | unsigned int relsec, | |
61 | struct module *me) | |
62 | { | |
63 | unsigned int i; | |
64 | Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr; | |
65 | Elf32_Sym *sym; | |
66 | uint32_t *location; | |
67 | ||
68 | DEBUGP("Applying relocate section %u to %u\n", relsec, | |
69 | sechdrs[relsec].sh_info); | |
70 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { | |
71 | /* This is where to make the change */ | |
72 | location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr | |
73 | + rel[i].r_offset; | |
74 | /* This is the symbol it is referring to. Note that all | |
75 | undefined symbols have been resolved. */ | |
76 | sym = (Elf32_Sym *)sechdrs[symindex].sh_addr | |
77 | + ELF32_R_SYM(rel[i].r_info); | |
78 | ||
79 | switch (ELF32_R_TYPE(rel[i].r_info)) { | |
80 | case R_386_32: | |
81 | /* We add the value into the location given */ | |
82 | *location += sym->st_value; | |
83 | break; | |
84 | case R_386_PC32: | |
85 | /* Add the value, subtract its postition */ | |
86 | *location += sym->st_value - (uint32_t)location; | |
87 | break; | |
88 | default: | |
89 | printk(KERN_ERR "module %s: Unknown relocation: %u\n", | |
90 | me->name, ELF32_R_TYPE(rel[i].r_info)); | |
91 | return -ENOEXEC; | |
92 | } | |
93 | } | |
94 | return 0; | |
95 | } | |
96 | ||
97 | int apply_relocate_add(Elf32_Shdr *sechdrs, | |
98 | const char *strtab, | |
99 | unsigned int symindex, | |
100 | unsigned int relsec, | |
101 | struct module *me) | |
102 | { | |
103 | printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n", | |
104 | me->name); | |
105 | return -ENOEXEC; | |
106 | } | |
107 | ||
1da177e4 LT |
108 | int module_finalize(const Elf_Ehdr *hdr, |
109 | const Elf_Shdr *sechdrs, | |
110 | struct module *me) | |
111 | { | |
139ec7c4 RR |
112 | const Elf_Shdr *s, *text = NULL, *alt = NULL, *locks = NULL, |
113 | *para = NULL; | |
1da177e4 LT |
114 | char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; |
115 | ||
1da177e4 | 116 | for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { |
9a0b5817 GH |
117 | if (!strcmp(".text", secstrings + s->sh_name)) |
118 | text = s; | |
119 | if (!strcmp(".altinstructions", secstrings + s->sh_name)) | |
120 | alt = s; | |
121 | if (!strcmp(".smp_locks", secstrings + s->sh_name)) | |
122 | locks= s; | |
139ec7c4 RR |
123 | if (!strcmp(".parainstructions", secstrings + s->sh_name)) |
124 | para = s; | |
9a0b5817 GH |
125 | } |
126 | ||
127 | if (alt) { | |
128 | /* patch .altinstructions */ | |
129 | void *aseg = (void *)alt->sh_addr; | |
130 | apply_alternatives(aseg, aseg + alt->sh_size); | |
131 | } | |
132 | if (locks && text) { | |
133 | void *lseg = (void *)locks->sh_addr; | |
134 | void *tseg = (void *)text->sh_addr; | |
135 | alternatives_smp_module_add(me, me->name, | |
136 | lseg, lseg + locks->sh_size, | |
137 | tseg, tseg + text->sh_size); | |
138 | } | |
139ec7c4 RR |
139 | |
140 | if (para) { | |
141 | void *pseg = (void *)para->sh_addr; | |
142 | apply_paravirt(pseg, pseg + para->sh_size); | |
143 | } | |
144 | ||
91768d6c | 145 | return module_bug_finalize(hdr, sechdrs, me); |
1da177e4 LT |
146 | } |
147 | ||
148 | void module_arch_cleanup(struct module *mod) | |
149 | { | |
9a0b5817 | 150 | alternatives_smp_module_del(mod); |
91768d6c | 151 | module_bug_cleanup(mod); |
1da177e4 | 152 | } |