module.c (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2) module.c (4e6a05fe5f87efd58da16fbf61e1f6329575fcfd)
1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 *
16 * Copyright (C) 2001 Rusty Russell.
17 * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
18 * Copyright (C) 2005 Thiemo Seufer
19 */
20
21#undef DEBUG
22
23#include <linux/moduleloader.h>
24#include <linux/elf.h>
25#include <linux/vmalloc.h>
26#include <linux/slab.h>
27#include <linux/fs.h>
28#include <linux/string.h>
29#include <linux/kernel.h>
1#include <linux/module.h>
2#include <linux/spinlock.h>
3
30#include <linux/module.h>
31#include <linux/spinlock.h>
32
33struct mips_hi16 {
34 struct mips_hi16 *next;
35 Elf_Addr *addr;
36 Elf_Addr value;
37};
38
39static struct mips_hi16 *mips_hi16_list;
40
4static LIST_HEAD(dbe_list);
5static DEFINE_SPINLOCK(dbe_lock);
6
41static LIST_HEAD(dbe_list);
42static DEFINE_SPINLOCK(dbe_lock);
43
44void *module_alloc(unsigned long size)
45{
46 if (size == 0)
47 return NULL;
48 return vmalloc(size);
49}
50
51/* Free memory returned from module_alloc */
52void module_free(struct module *mod, void *module_region)
53{
54 vfree(module_region);
55 /* FIXME: If module_region == mod->init_region, trim exception
56 table entries. */
57}
58
59int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
60 char *secstrings, struct module *mod)
61{
62 return 0;
63}
64
65static int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
66{
67 return 0;
68}
69
70static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
71{
72 *location += v;
73
74 return 0;
75}
76
77static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v)
78{
79 *location = v;
80
81 return 0;
82}
83
84static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
85{
86 if (v % 4) {
87 printk(KERN_ERR "module %s: dangerous relocation\n", me->name);
88 return -ENOEXEC;
89 }
90
91 if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
92 printk(KERN_ERR
93 "module %s: relocation overflow\n",
94 me->name);
95 return -ENOEXEC;
96 }
97
98 *location = (*location & ~0x03ffffff) |
99 ((*location + (v >> 2)) & 0x03ffffff);
100
101 return 0;
102}
103
104static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v)
105{
106 if (v % 4) {
107 printk(KERN_ERR "module %s: dangerous relocation\n", me->name);
108 return -ENOEXEC;
109 }
110
111 if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
112 printk(KERN_ERR
113 "module %s: relocation overflow\n",
114 me->name);
115 return -ENOEXEC;
116 }
117
118 *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff);
119
120 return 0;
121}
122
123static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v)
124{
125 struct mips_hi16 *n;
126
127 /*
128 * We cannot relocate this one now because we don't know the value of
129 * the carry we need to add. Save the information, and let LO16 do the
130 * actual relocation.
131 */
132 n = kmalloc(sizeof *n, GFP_KERNEL);
133 if (!n)
134 return -ENOMEM;
135
136 n->addr = (Elf_Addr *)location;
137 n->value = v;
138 n->next = mips_hi16_list;
139 mips_hi16_list = n;
140
141 return 0;
142}
143
144static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v)
145{
146 *location = (*location & 0xffff0000) |
147 ((((long long) v + 0x8000LL) >> 16) & 0xffff);
148
149 return 0;
150}
151
152static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v)
153{
154 unsigned long insnlo = *location;
155 Elf_Addr val, vallo;
156
157 /* Sign extend the addend we extract from the lo insn. */
158 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
159
160 if (mips_hi16_list != NULL) {
161 struct mips_hi16 *l;
162
163 l = mips_hi16_list;
164 while (l != NULL) {
165 struct mips_hi16 *next;
166 unsigned long insn;
167
168 /*
169 * The value for the HI16 had best be the same.
170 */
171 if (v != l->value)
172 goto out_danger;
173
174 /*
175 * Do the HI16 relocation. Note that we actually don't
176 * need to know anything about the LO16 itself, except
177 * where to find the low 16 bits of the addend needed
178 * by the LO16.
179 */
180 insn = *l->addr;
181 val = ((insn & 0xffff) << 16) + vallo;
182 val += v;
183
184 /*
185 * Account for the sign extension that will happen in
186 * the low bits.
187 */
188 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
189
190 insn = (insn & ~0xffff) | val;
191 *l->addr = insn;
192
193 next = l->next;
194 kfree(l);
195 l = next;
196 }
197
198 mips_hi16_list = NULL;
199 }
200
201 /*
202 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
203 */
204 val = v + vallo;
205 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
206 *location = insnlo;
207
208 return 0;
209
210out_danger:
211 printk(KERN_ERR "module %s: dangerous " "relocation\n", me->name);
212
213 return -ENOEXEC;
214}
215
216static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v)
217{
218 *location = (*location & 0xffff0000) | (v & 0xffff);
219
220 return 0;
221}
222
223static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v)
224{
225 *(Elf_Addr *)location = v;
226
227 return 0;
228}
229
230static int apply_r_mips_higher_rela(struct module *me, u32 *location,
231 Elf_Addr v)
232{
233 *location = (*location & 0xffff0000) |
234 ((((long long) v + 0x80008000LL) >> 32) & 0xffff);
235
236 return 0;
237}
238
239static int apply_r_mips_highest_rela(struct module *me, u32 *location,
240 Elf_Addr v)
241{
242 *location = (*location & 0xffff0000) |
243 ((((long long) v + 0x800080008000LL) >> 48) & 0xffff);
244
245 return 0;
246}
247
248static int (*reloc_handlers_rel[]) (struct module *me, u32 *location,
249 Elf_Addr v) = {
250 [R_MIPS_NONE] = apply_r_mips_none,
251 [R_MIPS_32] = apply_r_mips_32_rel,
252 [R_MIPS_26] = apply_r_mips_26_rel,
253 [R_MIPS_HI16] = apply_r_mips_hi16_rel,
254 [R_MIPS_LO16] = apply_r_mips_lo16_rel
255};
256
257static int (*reloc_handlers_rela[]) (struct module *me, u32 *location,
258 Elf_Addr v) = {
259 [R_MIPS_NONE] = apply_r_mips_none,
260 [R_MIPS_32] = apply_r_mips_32_rela,
261 [R_MIPS_26] = apply_r_mips_26_rela,
262 [R_MIPS_HI16] = apply_r_mips_hi16_rela,
263 [R_MIPS_LO16] = apply_r_mips_lo16_rela,
264 [R_MIPS_64] = apply_r_mips_64_rela,
265 [R_MIPS_HIGHER] = apply_r_mips_higher_rela,
266 [R_MIPS_HIGHEST] = apply_r_mips_highest_rela
267};
268
269int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
270 unsigned int symindex, unsigned int relsec,
271 struct module *me)
272{
273 Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr;
274 Elf_Sym *sym;
275 u32 *location;
276 unsigned int i;
277 Elf_Addr v;
278 int res;
279
280 pr_debug("Applying relocate section %u to %u\n", relsec,
281 sechdrs[relsec].sh_info);
282
283 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
284 /* This is where to make the change */
285 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
286 + rel[i].r_offset;
287 /* This is the symbol it is referring to */
288 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
289 + ELF_MIPS_R_SYM(rel[i]);
290 if (!sym->st_value) {
291 printk(KERN_WARNING "%s: Unknown symbol %s\n",
292 me->name, strtab + sym->st_name);
293 return -ENOENT;
294 }
295
296 v = sym->st_value;
297
298 res = reloc_handlers_rel[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
299 if (res)
300 return res;
301 }
302
303 return 0;
304}
305
306int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
307 unsigned int symindex, unsigned int relsec,
308 struct module *me)
309{
310 Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr;
311 Elf_Sym *sym;
312 u32 *location;
313 unsigned int i;
314 Elf_Addr v;
315 int res;
316
317 pr_debug("Applying relocate section %u to %u\n", relsec,
318 sechdrs[relsec].sh_info);
319
320 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
321 /* This is where to make the change */
322 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
323 + rel[i].r_offset;
324 /* This is the symbol it is referring to */
325 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
326 + ELF_MIPS_R_SYM(rel[i]);
327 if (!sym->st_value) {
328 printk(KERN_WARNING "%s: Unknown symbol %s\n",
329 me->name, strtab + sym->st_name);
330 return -ENOENT;
331 }
332
333 v = sym->st_value + rel[i].r_addend;
334
335 res = reloc_handlers_rela[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
336 if (res)
337 return res;
338 }
339
340 return 0;
341}
342
7/* Given an address, look for it in the module exception tables. */
8const struct exception_table_entry *search_module_dbetables(unsigned long addr)
9{
10 unsigned long flags;
11 const struct exception_table_entry *e = NULL;
12 struct mod_arch_specific *dbe;
13
14 spin_lock_irqsave(&dbe_lock, flags);

--- 39 unchanged lines hidden --- 		343/* Given an address, look for it in the module exception tables. */
344const struct exception_table_entry *search_module_dbetables(unsigned long addr)
345{
346 unsigned long flags;
347 const struct exception_table_entry *e = NULL;
348 struct mod_arch_specific *dbe;
349
350 spin_lock_irqsave(&dbe_lock, flags);

--- 39 unchanged lines hidden ---