ia64/linux-2.6.18-xen.hg

view arch/mips/kernel/module.c @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
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 */
21 #undef DEBUG
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>
30 #include <linux/module.h>
31 #include <linux/spinlock.h>
33 struct mips_hi16 {
34 struct mips_hi16 *next;
35 Elf_Addr *addr;
36 Elf_Addr value;
37 };
39 static struct mips_hi16 *mips_hi16_list;
41 static LIST_HEAD(dbe_list);
42 static DEFINE_SPINLOCK(dbe_lock);
44 void *module_alloc(unsigned long size)
45 {
46 if (size == 0)
47 return NULL;
48 return vmalloc(size);
49 }
51 /* Free memory returned from module_alloc */
52 void 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 }
59 int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
60 char *secstrings, struct module *mod)
61 {
62 return 0;
63 }
65 static int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
66 {
67 return 0;
68 }
70 static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
71 {
72 *location += v;
74 return 0;
75 }
77 static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v)
78 {
79 *location = v;
81 return 0;
82 }
84 static 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 }
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 }
98 *location = (*location & ~0x03ffffff) |
99 ((*location + (v >> 2)) & 0x03ffffff);
101 return 0;
102 }
104 static 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 }
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 }
118 *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff);
120 return 0;
121 }
123 static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v)
124 {
125 struct mips_hi16 *n;
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;
136 n->addr = (Elf_Addr *)location;
137 n->value = v;
138 n->next = mips_hi16_list;
139 mips_hi16_list = n;
141 return 0;
142 }
144 static 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);
149 return 0;
150 }
152 static 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;
157 /* Sign extend the addend we extract from the lo insn. */
158 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
160 if (mips_hi16_list != NULL) {
161 struct mips_hi16 *l;
163 l = mips_hi16_list;
164 while (l != NULL) {
165 struct mips_hi16 *next;
166 unsigned long insn;
168 /*
169 * The value for the HI16 had best be the same.
170 */
171 if (v != l->value)
172 goto out_danger;
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;
184 /*
185 * Account for the sign extension that will happen in
186 * the low bits.
187 */
188 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
190 insn = (insn & ~0xffff) | val;
191 *l->addr = insn;
193 next = l->next;
194 kfree(l);
195 l = next;
196 }
198 mips_hi16_list = NULL;
199 }
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;
208 return 0;
210 out_danger:
211 printk(KERN_ERR "module %s: dangerous " "relocation\n", me->name);
213 return -ENOEXEC;
214 }
216 static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v)
217 {
218 *location = (*location & 0xffff0000) | (v & 0xffff);
220 return 0;
221 }
223 static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v)
224 {
225 *(Elf_Addr *)location = v;
227 return 0;
228 }
230 static 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);
236 return 0;
237 }
239 static 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);
245 return 0;
246 }
248 static 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 };
257 static 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 };
269 int 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;
280 pr_debug("Applying relocate section %u to %u\n", relsec,
281 sechdrs[relsec].sh_info);
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 /* Ignore unresolved weak symbol */
292 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
293 continue;
294 printk(KERN_WARNING "%s: Unknown symbol %s\n",
295 me->name, strtab + sym->st_name);
296 return -ENOENT;
297 }
299 v = sym->st_value;
301 res = reloc_handlers_rel[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
302 if (res)
303 return res;
304 }
306 return 0;
307 }
309 int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
310 unsigned int symindex, unsigned int relsec,
311 struct module *me)
312 {
313 Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr;
314 Elf_Sym *sym;
315 u32 *location;
316 unsigned int i;
317 Elf_Addr v;
318 int res;
320 pr_debug("Applying relocate section %u to %u\n", relsec,
321 sechdrs[relsec].sh_info);
323 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
324 /* This is where to make the change */
325 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
326 + rel[i].r_offset;
327 /* This is the symbol it is referring to */
328 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
329 + ELF_MIPS_R_SYM(rel[i]);
330 if (!sym->st_value) {
331 /* Ignore unresolved weak symbol */
332 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
333 continue;
334 printk(KERN_WARNING "%s: Unknown symbol %s\n",
335 me->name, strtab + sym->st_name);
336 return -ENOENT;
337 }
339 v = sym->st_value + rel[i].r_addend;
341 res = reloc_handlers_rela[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
342 if (res)
343 return res;
344 }
346 return 0;
347 }
349 /* Given an address, look for it in the module exception tables. */
350 const struct exception_table_entry *search_module_dbetables(unsigned long addr)
351 {
352 unsigned long flags;
353 const struct exception_table_entry *e = NULL;
354 struct mod_arch_specific *dbe;
356 spin_lock_irqsave(&dbe_lock, flags);
357 list_for_each_entry(dbe, &dbe_list, dbe_list) {
358 e = search_extable(dbe->dbe_start, dbe->dbe_end - 1, addr);
359 if (e)
360 break;
361 }
362 spin_unlock_irqrestore(&dbe_lock, flags);
364 /* Now, if we found one, we are running inside it now, hence
365 we cannot unload the module, hence no refcnt needed. */
366 return e;
367 }
369 /* Put in dbe list if neccessary. */
370 int module_finalize(const Elf_Ehdr *hdr,
371 const Elf_Shdr *sechdrs,
372 struct module *me)
373 {
374 const Elf_Shdr *s;
375 char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
377 INIT_LIST_HEAD(&me->arch.dbe_list);
378 for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
379 if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
380 continue;
381 me->arch.dbe_start = (void *)s->sh_addr;
382 me->arch.dbe_end = (void *)s->sh_addr + s->sh_size;
383 spin_lock_irq(&dbe_lock);
384 list_add(&me->arch.dbe_list, &dbe_list);
385 spin_unlock_irq(&dbe_lock);
386 }
387 return 0;
388 }
390 void module_arch_cleanup(struct module *mod)
391 {
392 spin_lock_irq(&dbe_lock);
393 list_del(&mod->arch.dbe_list);
394 spin_unlock_irq(&dbe_lock);
395 }