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1/*
2 * Kernel module help for s390.
3 *
4 * S390 version
5 * Copyright IBM Corp. 2002, 2003
6 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
7 * Martin Schwidefsky (schwidefsky@de.ibm.com)
8 *
9 * based on i386 version
10 * Copyright (C) 2001 Rusty Russell.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26#include <linux/module.h>
27#include <linux/elf.h>
28#include <linux/vmalloc.h>
29#include <linux/fs.h>
30#include <linux/string.h>
31#include <linux/kernel.h>
32#include <linux/moduleloader.h>
33#include <linux/bug.h>
34
35#if 0
36#define DEBUGP printk
37#else
38#define DEBUGP(fmt , ...)
39#endif
40
41#define PLT_ENTRY_SIZE 20
42
43void *module_alloc(unsigned long size)
44{
45 if (PAGE_ALIGN(size) > MODULES_LEN)
46 return NULL;
47 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
48 GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
49 __builtin_return_address(0));
50}
51
52void module_arch_freeing_init(struct module *mod)
53{
54 if (is_livepatch_module(mod) &&
55 mod->state == MODULE_STATE_LIVE)
56 return;
57
58 vfree(mod->arch.syminfo);
59 mod->arch.syminfo = NULL;
60}
61
62static void check_rela(Elf_Rela *rela, struct module *me)
63{
64 struct mod_arch_syminfo *info;
65
66 info = me->arch.syminfo + ELF_R_SYM (rela->r_info);
67 switch (ELF_R_TYPE (rela->r_info)) {
68 case R_390_GOT12: /* 12 bit GOT offset. */
69 case R_390_GOT16: /* 16 bit GOT offset. */
70 case R_390_GOT20: /* 20 bit GOT offset. */
71 case R_390_GOT32: /* 32 bit GOT offset. */
72 case R_390_GOT64: /* 64 bit GOT offset. */
73 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
74 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
75 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
76 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
77 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
78 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
79 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
80 if (info->got_offset == -1UL) {
81 info->got_offset = me->arch.got_size;
82 me->arch.got_size += sizeof(void*);
83 }
84 break;
85 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
86 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
87 case R_390_PLT32: /* 32 bit PC relative PLT address. */
88 case R_390_PLT64: /* 64 bit PC relative PLT address. */
89 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
90 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
91 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
92 if (info->plt_offset == -1UL) {
93 info->plt_offset = me->arch.plt_size;
94 me->arch.plt_size += PLT_ENTRY_SIZE;
95 }
96 break;
97 case R_390_COPY:
98 case R_390_GLOB_DAT:
99 case R_390_JMP_SLOT:
100 case R_390_RELATIVE:
101 /* Only needed if we want to support loading of
102 modules linked with -shared. */
103 break;
104 }
105}
106
107/*
108 * Account for GOT and PLT relocations. We can't add sections for
109 * got and plt but we can increase the core module size.
110 */
111int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
112 char *secstrings, struct module *me)
113{
114 Elf_Shdr *symtab;
115 Elf_Sym *symbols;
116 Elf_Rela *rela;
117 char *strings;
118 int nrela, i, j;
119
120 /* Find symbol table and string table. */
121 symtab = NULL;
122 for (i = 0; i < hdr->e_shnum; i++)
123 switch (sechdrs[i].sh_type) {
124 case SHT_SYMTAB:
125 symtab = sechdrs + i;
126 break;
127 }
128 if (!symtab) {
129 printk(KERN_ERR "module %s: no symbol table\n", me->name);
130 return -ENOEXEC;
131 }
132
133 /* Allocate one syminfo structure per symbol. */
134 me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym);
135 me->arch.syminfo = vmalloc(me->arch.nsyms *
136 sizeof(struct mod_arch_syminfo));
137 if (!me->arch.syminfo)
138 return -ENOMEM;
139 symbols = (void *) hdr + symtab->sh_offset;
140 strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset;
141 for (i = 0; i < me->arch.nsyms; i++) {
142 if (symbols[i].st_shndx == SHN_UNDEF &&
143 strcmp(strings + symbols[i].st_name,
144 "_GLOBAL_OFFSET_TABLE_") == 0)
145 /* "Define" it as absolute. */
146 symbols[i].st_shndx = SHN_ABS;
147 me->arch.syminfo[i].got_offset = -1UL;
148 me->arch.syminfo[i].plt_offset = -1UL;
149 me->arch.syminfo[i].got_initialized = 0;
150 me->arch.syminfo[i].plt_initialized = 0;
151 }
152
153 /* Search for got/plt relocations. */
154 me->arch.got_size = me->arch.plt_size = 0;
155 for (i = 0; i < hdr->e_shnum; i++) {
156 if (sechdrs[i].sh_type != SHT_RELA)
157 continue;
158 nrela = sechdrs[i].sh_size / sizeof(Elf_Rela);
159 rela = (void *) hdr + sechdrs[i].sh_offset;
160 for (j = 0; j < nrela; j++)
161 check_rela(rela + j, me);
162 }
163
164 /* Increase core size by size of got & plt and set start
165 offsets for got and plt. */
166 me->core_layout.size = ALIGN(me->core_layout.size, 4);
167 me->arch.got_offset = me->core_layout.size;
168 me->core_layout.size += me->arch.got_size;
169 me->arch.plt_offset = me->core_layout.size;
170 me->core_layout.size += me->arch.plt_size;
171 return 0;
172}
173
174static int apply_rela_bits(Elf_Addr loc, Elf_Addr val,
175 int sign, int bits, int shift)
176{
177 unsigned long umax;
178 long min, max;
179
180 if (val & ((1UL << shift) - 1))
181 return -ENOEXEC;
182 if (sign) {
183 val = (Elf_Addr)(((long) val) >> shift);
184 min = -(1L << (bits - 1));
185 max = (1L << (bits - 1)) - 1;
186 if ((long) val < min || (long) val > max)
187 return -ENOEXEC;
188 } else {
189 val >>= shift;
190 umax = ((1UL << (bits - 1)) << 1) - 1;
191 if ((unsigned long) val > umax)
192 return -ENOEXEC;
193 }
194
195 if (bits == 8)
196 *(unsigned char *) loc = val;
197 else if (bits == 12)
198 *(unsigned short *) loc = (val & 0xfff) |
199 (*(unsigned short *) loc & 0xf000);
200 else if (bits == 16)
201 *(unsigned short *) loc = val;
202 else if (bits == 20)
203 *(unsigned int *) loc = (val & 0xfff) << 16 |
204 (val & 0xff000) >> 4 |
205 (*(unsigned int *) loc & 0xf00000ff);
206 else if (bits == 32)
207 *(unsigned int *) loc = val;
208 else if (bits == 64)
209 *(unsigned long *) loc = val;
210 return 0;
211}
212
213static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
214 const char *strtab, struct module *me)
215{
216 struct mod_arch_syminfo *info;
217 Elf_Addr loc, val;
218 int r_type, r_sym;
219 int rc = -ENOEXEC;
220
221 /* This is where to make the change */
222 loc = base + rela->r_offset;
223 /* This is the symbol it is referring to. Note that all
224 undefined symbols have been resolved. */
225 r_sym = ELF_R_SYM(rela->r_info);
226 r_type = ELF_R_TYPE(rela->r_info);
227 info = me->arch.syminfo + r_sym;
228 val = symtab[r_sym].st_value;
229
230 switch (r_type) {
231 case R_390_NONE: /* No relocation. */
232 rc = 0;
233 break;
234 case R_390_8: /* Direct 8 bit. */
235 case R_390_12: /* Direct 12 bit. */
236 case R_390_16: /* Direct 16 bit. */
237 case R_390_20: /* Direct 20 bit. */
238 case R_390_32: /* Direct 32 bit. */
239 case R_390_64: /* Direct 64 bit. */
240 val += rela->r_addend;
241 if (r_type == R_390_8)
242 rc = apply_rela_bits(loc, val, 0, 8, 0);
243 else if (r_type == R_390_12)
244 rc = apply_rela_bits(loc, val, 0, 12, 0);
245 else if (r_type == R_390_16)
246 rc = apply_rela_bits(loc, val, 0, 16, 0);
247 else if (r_type == R_390_20)
248 rc = apply_rela_bits(loc, val, 1, 20, 0);
249 else if (r_type == R_390_32)
250 rc = apply_rela_bits(loc, val, 0, 32, 0);
251 else if (r_type == R_390_64)
252 rc = apply_rela_bits(loc, val, 0, 64, 0);
253 break;
254 case R_390_PC16: /* PC relative 16 bit. */
255 case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */
256 case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */
257 case R_390_PC32: /* PC relative 32 bit. */
258 case R_390_PC64: /* PC relative 64 bit. */
259 val += rela->r_addend - loc;
260 if (r_type == R_390_PC16)
261 rc = apply_rela_bits(loc, val, 1, 16, 0);
262 else if (r_type == R_390_PC16DBL)
263 rc = apply_rela_bits(loc, val, 1, 16, 1);
264 else if (r_type == R_390_PC32DBL)
265 rc = apply_rela_bits(loc, val, 1, 32, 1);
266 else if (r_type == R_390_PC32)
267 rc = apply_rela_bits(loc, val, 1, 32, 0);
268 else if (r_type == R_390_PC64)
269 rc = apply_rela_bits(loc, val, 1, 64, 0);
270 break;
271 case R_390_GOT12: /* 12 bit GOT offset. */
272 case R_390_GOT16: /* 16 bit GOT offset. */
273 case R_390_GOT20: /* 20 bit GOT offset. */
274 case R_390_GOT32: /* 32 bit GOT offset. */
275 case R_390_GOT64: /* 64 bit GOT offset. */
276 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
277 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
278 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
279 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
280 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
281 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
282 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
283 if (info->got_initialized == 0) {
284 Elf_Addr *gotent;
285
286 gotent = me->core_layout.base + me->arch.got_offset +
287 info->got_offset;
288 *gotent = val;
289 info->got_initialized = 1;
290 }
291 val = info->got_offset + rela->r_addend;
292 if (r_type == R_390_GOT12 ||
293 r_type == R_390_GOTPLT12)
294 rc = apply_rela_bits(loc, val, 0, 12, 0);
295 else if (r_type == R_390_GOT16 ||
296 r_type == R_390_GOTPLT16)
297 rc = apply_rela_bits(loc, val, 0, 16, 0);
298 else if (r_type == R_390_GOT20 ||
299 r_type == R_390_GOTPLT20)
300 rc = apply_rela_bits(loc, val, 1, 20, 0);
301 else if (r_type == R_390_GOT32 ||
302 r_type == R_390_GOTPLT32)
303 rc = apply_rela_bits(loc, val, 0, 32, 0);
304 else if (r_type == R_390_GOT64 ||
305 r_type == R_390_GOTPLT64)
306 rc = apply_rela_bits(loc, val, 0, 64, 0);
307 else if (r_type == R_390_GOTENT ||
308 r_type == R_390_GOTPLTENT) {
309 val += (Elf_Addr) me->core_layout.base - loc;
310 rc = apply_rela_bits(loc, val, 1, 32, 1);
311 }
312 break;
313 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
314 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
315 case R_390_PLT32: /* 32 bit PC relative PLT address. */
316 case R_390_PLT64: /* 64 bit PC relative PLT address. */
317 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
318 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
319 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
320 if (info->plt_initialized == 0) {
321 unsigned int *ip;
322 ip = me->core_layout.base + me->arch.plt_offset +
323 info->plt_offset;
324 ip[0] = 0x0d10e310; /* basr 1,0; lg 1,10(1); br 1 */
325 ip[1] = 0x100a0004;
326 ip[2] = 0x07f10000;
327 ip[3] = (unsigned int) (val >> 32);
328 ip[4] = (unsigned int) val;
329 info->plt_initialized = 1;
330 }
331 if (r_type == R_390_PLTOFF16 ||
332 r_type == R_390_PLTOFF32 ||
333 r_type == R_390_PLTOFF64)
334 val = me->arch.plt_offset - me->arch.got_offset +
335 info->plt_offset + rela->r_addend;
336 else {
337 if (!((r_type == R_390_PLT16DBL &&
338 val - loc + 0xffffUL < 0x1ffffeUL) ||
339 (r_type == R_390_PLT32DBL &&
340 val - loc + 0xffffffffULL < 0x1fffffffeULL)))
341 val = (Elf_Addr) me->core_layout.base +
342 me->arch.plt_offset +
343 info->plt_offset;
344 val += rela->r_addend - loc;
345 }
346 if (r_type == R_390_PLT16DBL)
347 rc = apply_rela_bits(loc, val, 1, 16, 1);
348 else if (r_type == R_390_PLTOFF16)
349 rc = apply_rela_bits(loc, val, 0, 16, 0);
350 else if (r_type == R_390_PLT32DBL)
351 rc = apply_rela_bits(loc, val, 1, 32, 1);
352 else if (r_type == R_390_PLT32 ||
353 r_type == R_390_PLTOFF32)
354 rc = apply_rela_bits(loc, val, 0, 32, 0);
355 else if (r_type == R_390_PLT64 ||
356 r_type == R_390_PLTOFF64)
357 rc = apply_rela_bits(loc, val, 0, 64, 0);
358 break;
359 case R_390_GOTOFF16: /* 16 bit offset to GOT. */
360 case R_390_GOTOFF32: /* 32 bit offset to GOT. */
361 case R_390_GOTOFF64: /* 64 bit offset to GOT. */
362 val = val + rela->r_addend -
363 ((Elf_Addr) me->core_layout.base + me->arch.got_offset);
364 if (r_type == R_390_GOTOFF16)
365 rc = apply_rela_bits(loc, val, 0, 16, 0);
366 else if (r_type == R_390_GOTOFF32)
367 rc = apply_rela_bits(loc, val, 0, 32, 0);
368 else if (r_type == R_390_GOTOFF64)
369 rc = apply_rela_bits(loc, val, 0, 64, 0);
370 break;
371 case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */
372 case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */
373 val = (Elf_Addr) me->core_layout.base + me->arch.got_offset +
374 rela->r_addend - loc;
375 if (r_type == R_390_GOTPC)
376 rc = apply_rela_bits(loc, val, 1, 32, 0);
377 else if (r_type == R_390_GOTPCDBL)
378 rc = apply_rela_bits(loc, val, 1, 32, 1);
379 break;
380 case R_390_COPY:
381 case R_390_GLOB_DAT: /* Create GOT entry. */
382 case R_390_JMP_SLOT: /* Create PLT entry. */
383 case R_390_RELATIVE: /* Adjust by program base. */
384 /* Only needed if we want to support loading of
385 modules linked with -shared. */
386 return -ENOEXEC;
387 default:
388 printk(KERN_ERR "module %s: unknown relocation: %u\n",
389 me->name, r_type);
390 return -ENOEXEC;
391 }
392 if (rc) {
393 printk(KERN_ERR "module %s: relocation error for symbol %s "
394 "(r_type %i, value 0x%lx)\n",
395 me->name, strtab + symtab[r_sym].st_name,
396 r_type, (unsigned long) val);
397 return rc;
398 }
399 return 0;
400}
401
402int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
403 unsigned int symindex, unsigned int relsec,
404 struct module *me)
405{
406 Elf_Addr base;
407 Elf_Sym *symtab;
408 Elf_Rela *rela;
409 unsigned long i, n;
410 int rc;
411
412 DEBUGP("Applying relocate section %u to %u\n",
413 relsec, sechdrs[relsec].sh_info);
414 base = sechdrs[sechdrs[relsec].sh_info].sh_addr;
415 symtab = (Elf_Sym *) sechdrs[symindex].sh_addr;
416 rela = (Elf_Rela *) sechdrs[relsec].sh_addr;
417 n = sechdrs[relsec].sh_size / sizeof(Elf_Rela);
418
419 for (i = 0; i < n; i++, rela++) {
420 rc = apply_rela(rela, base, symtab, strtab, me);
421 if (rc)
422 return rc;
423 }
424 return 0;
425}
426
427int module_finalize(const Elf_Ehdr *hdr,
428 const Elf_Shdr *sechdrs,
429 struct module *me)
430{
431 jump_label_apply_nops(me);
432 return 0;
433}
1/*
2 * Kernel module help for s390.
3 *
4 * S390 version
5 * Copyright IBM Corp. 2002, 2003
6 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
7 * Martin Schwidefsky (schwidefsky@de.ibm.com)
8 *
9 * based on i386 version
10 * Copyright (C) 2001 Rusty Russell.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26#include <linux/module.h>
27#include <linux/elf.h>
28#include <linux/vmalloc.h>
29#include <linux/fs.h>
30#include <linux/string.h>
31#include <linux/kernel.h>
32#include <linux/moduleloader.h>
33#include <linux/bug.h>
34
35#if 0
36#define DEBUGP printk
37#else
38#define DEBUGP(fmt , ...)
39#endif
40
41#define PLT_ENTRY_SIZE 20
42
43void *module_alloc(unsigned long size)
44{
45 if (PAGE_ALIGN(size) > MODULES_LEN)
46 return NULL;
47 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
48 GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
49 __builtin_return_address(0));
50}
51
52void module_arch_freeing_init(struct module *mod)
53{
54 vfree(mod->arch.syminfo);
55 mod->arch.syminfo = NULL;
56}
57
58static void check_rela(Elf_Rela *rela, struct module *me)
59{
60 struct mod_arch_syminfo *info;
61
62 info = me->arch.syminfo + ELF_R_SYM (rela->r_info);
63 switch (ELF_R_TYPE (rela->r_info)) {
64 case R_390_GOT12: /* 12 bit GOT offset. */
65 case R_390_GOT16: /* 16 bit GOT offset. */
66 case R_390_GOT20: /* 20 bit GOT offset. */
67 case R_390_GOT32: /* 32 bit GOT offset. */
68 case R_390_GOT64: /* 64 bit GOT offset. */
69 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
70 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
71 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
72 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
73 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
74 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
75 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
76 if (info->got_offset == -1UL) {
77 info->got_offset = me->arch.got_size;
78 me->arch.got_size += sizeof(void*);
79 }
80 break;
81 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
82 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
83 case R_390_PLT32: /* 32 bit PC relative PLT address. */
84 case R_390_PLT64: /* 64 bit PC relative PLT address. */
85 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
86 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
87 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
88 if (info->plt_offset == -1UL) {
89 info->plt_offset = me->arch.plt_size;
90 me->arch.plt_size += PLT_ENTRY_SIZE;
91 }
92 break;
93 case R_390_COPY:
94 case R_390_GLOB_DAT:
95 case R_390_JMP_SLOT:
96 case R_390_RELATIVE:
97 /* Only needed if we want to support loading of
98 modules linked with -shared. */
99 break;
100 }
101}
102
103/*
104 * Account for GOT and PLT relocations. We can't add sections for
105 * got and plt but we can increase the core module size.
106 */
107int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
108 char *secstrings, struct module *me)
109{
110 Elf_Shdr *symtab;
111 Elf_Sym *symbols;
112 Elf_Rela *rela;
113 char *strings;
114 int nrela, i, j;
115
116 /* Find symbol table and string table. */
117 symtab = NULL;
118 for (i = 0; i < hdr->e_shnum; i++)
119 switch (sechdrs[i].sh_type) {
120 case SHT_SYMTAB:
121 symtab = sechdrs + i;
122 break;
123 }
124 if (!symtab) {
125 printk(KERN_ERR "module %s: no symbol table\n", me->name);
126 return -ENOEXEC;
127 }
128
129 /* Allocate one syminfo structure per symbol. */
130 me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym);
131 me->arch.syminfo = vmalloc(me->arch.nsyms *
132 sizeof(struct mod_arch_syminfo));
133 if (!me->arch.syminfo)
134 return -ENOMEM;
135 symbols = (void *) hdr + symtab->sh_offset;
136 strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset;
137 for (i = 0; i < me->arch.nsyms; i++) {
138 if (symbols[i].st_shndx == SHN_UNDEF &&
139 strcmp(strings + symbols[i].st_name,
140 "_GLOBAL_OFFSET_TABLE_") == 0)
141 /* "Define" it as absolute. */
142 symbols[i].st_shndx = SHN_ABS;
143 me->arch.syminfo[i].got_offset = -1UL;
144 me->arch.syminfo[i].plt_offset = -1UL;
145 me->arch.syminfo[i].got_initialized = 0;
146 me->arch.syminfo[i].plt_initialized = 0;
147 }
148
149 /* Search for got/plt relocations. */
150 me->arch.got_size = me->arch.plt_size = 0;
151 for (i = 0; i < hdr->e_shnum; i++) {
152 if (sechdrs[i].sh_type != SHT_RELA)
153 continue;
154 nrela = sechdrs[i].sh_size / sizeof(Elf_Rela);
155 rela = (void *) hdr + sechdrs[i].sh_offset;
156 for (j = 0; j < nrela; j++)
157 check_rela(rela + j, me);
158 }
159
160 /* Increase core size by size of got & plt and set start
161 offsets for got and plt. */
162 me->core_layout.size = ALIGN(me->core_layout.size, 4);
163 me->arch.got_offset = me->core_layout.size;
164 me->core_layout.size += me->arch.got_size;
165 me->arch.plt_offset = me->core_layout.size;
166 me->core_layout.size += me->arch.plt_size;
167 return 0;
168}
169
170static int apply_rela_bits(Elf_Addr loc, Elf_Addr val,
171 int sign, int bits, int shift)
172{
173 unsigned long umax;
174 long min, max;
175
176 if (val & ((1UL << shift) - 1))
177 return -ENOEXEC;
178 if (sign) {
179 val = (Elf_Addr)(((long) val) >> shift);
180 min = -(1L << (bits - 1));
181 max = (1L << (bits - 1)) - 1;
182 if ((long) val < min || (long) val > max)
183 return -ENOEXEC;
184 } else {
185 val >>= shift;
186 umax = ((1UL << (bits - 1)) << 1) - 1;
187 if ((unsigned long) val > umax)
188 return -ENOEXEC;
189 }
190
191 if (bits == 8)
192 *(unsigned char *) loc = val;
193 else if (bits == 12)
194 *(unsigned short *) loc = (val & 0xfff) |
195 (*(unsigned short *) loc & 0xf000);
196 else if (bits == 16)
197 *(unsigned short *) loc = val;
198 else if (bits == 20)
199 *(unsigned int *) loc = (val & 0xfff) << 16 |
200 (val & 0xff000) >> 4 |
201 (*(unsigned int *) loc & 0xf00000ff);
202 else if (bits == 32)
203 *(unsigned int *) loc = val;
204 else if (bits == 64)
205 *(unsigned long *) loc = val;
206 return 0;
207}
208
209static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
210 const char *strtab, struct module *me)
211{
212 struct mod_arch_syminfo *info;
213 Elf_Addr loc, val;
214 int r_type, r_sym;
215 int rc = -ENOEXEC;
216
217 /* This is where to make the change */
218 loc = base + rela->r_offset;
219 /* This is the symbol it is referring to. Note that all
220 undefined symbols have been resolved. */
221 r_sym = ELF_R_SYM(rela->r_info);
222 r_type = ELF_R_TYPE(rela->r_info);
223 info = me->arch.syminfo + r_sym;
224 val = symtab[r_sym].st_value;
225
226 switch (r_type) {
227 case R_390_NONE: /* No relocation. */
228 rc = 0;
229 break;
230 case R_390_8: /* Direct 8 bit. */
231 case R_390_12: /* Direct 12 bit. */
232 case R_390_16: /* Direct 16 bit. */
233 case R_390_20: /* Direct 20 bit. */
234 case R_390_32: /* Direct 32 bit. */
235 case R_390_64: /* Direct 64 bit. */
236 val += rela->r_addend;
237 if (r_type == R_390_8)
238 rc = apply_rela_bits(loc, val, 0, 8, 0);
239 else if (r_type == R_390_12)
240 rc = apply_rela_bits(loc, val, 0, 12, 0);
241 else if (r_type == R_390_16)
242 rc = apply_rela_bits(loc, val, 0, 16, 0);
243 else if (r_type == R_390_20)
244 rc = apply_rela_bits(loc, val, 1, 20, 0);
245 else if (r_type == R_390_32)
246 rc = apply_rela_bits(loc, val, 0, 32, 0);
247 else if (r_type == R_390_64)
248 rc = apply_rela_bits(loc, val, 0, 64, 0);
249 break;
250 case R_390_PC16: /* PC relative 16 bit. */
251 case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */
252 case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */
253 case R_390_PC32: /* PC relative 32 bit. */
254 case R_390_PC64: /* PC relative 64 bit. */
255 val += rela->r_addend - loc;
256 if (r_type == R_390_PC16)
257 rc = apply_rela_bits(loc, val, 1, 16, 0);
258 else if (r_type == R_390_PC16DBL)
259 rc = apply_rela_bits(loc, val, 1, 16, 1);
260 else if (r_type == R_390_PC32DBL)
261 rc = apply_rela_bits(loc, val, 1, 32, 1);
262 else if (r_type == R_390_PC32)
263 rc = apply_rela_bits(loc, val, 1, 32, 0);
264 else if (r_type == R_390_PC64)
265 rc = apply_rela_bits(loc, val, 1, 64, 0);
266 break;
267 case R_390_GOT12: /* 12 bit GOT offset. */
268 case R_390_GOT16: /* 16 bit GOT offset. */
269 case R_390_GOT20: /* 20 bit GOT offset. */
270 case R_390_GOT32: /* 32 bit GOT offset. */
271 case R_390_GOT64: /* 64 bit GOT offset. */
272 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
273 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
274 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
275 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
276 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
277 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
278 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
279 if (info->got_initialized == 0) {
280 Elf_Addr *gotent;
281
282 gotent = me->core_layout.base + me->arch.got_offset +
283 info->got_offset;
284 *gotent = val;
285 info->got_initialized = 1;
286 }
287 val = info->got_offset + rela->r_addend;
288 if (r_type == R_390_GOT12 ||
289 r_type == R_390_GOTPLT12)
290 rc = apply_rela_bits(loc, val, 0, 12, 0);
291 else if (r_type == R_390_GOT16 ||
292 r_type == R_390_GOTPLT16)
293 rc = apply_rela_bits(loc, val, 0, 16, 0);
294 else if (r_type == R_390_GOT20 ||
295 r_type == R_390_GOTPLT20)
296 rc = apply_rela_bits(loc, val, 1, 20, 0);
297 else if (r_type == R_390_GOT32 ||
298 r_type == R_390_GOTPLT32)
299 rc = apply_rela_bits(loc, val, 0, 32, 0);
300 else if (r_type == R_390_GOT64 ||
301 r_type == R_390_GOTPLT64)
302 rc = apply_rela_bits(loc, val, 0, 64, 0);
303 else if (r_type == R_390_GOTENT ||
304 r_type == R_390_GOTPLTENT) {
305 val += (Elf_Addr) me->core_layout.base - loc;
306 rc = apply_rela_bits(loc, val, 1, 32, 1);
307 }
308 break;
309 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
310 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
311 case R_390_PLT32: /* 32 bit PC relative PLT address. */
312 case R_390_PLT64: /* 64 bit PC relative PLT address. */
313 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
314 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
315 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
316 if (info->plt_initialized == 0) {
317 unsigned int *ip;
318 ip = me->core_layout.base + me->arch.plt_offset +
319 info->plt_offset;
320 ip[0] = 0x0d10e310; /* basr 1,0; lg 1,10(1); br 1 */
321 ip[1] = 0x100a0004;
322 ip[2] = 0x07f10000;
323 ip[3] = (unsigned int) (val >> 32);
324 ip[4] = (unsigned int) val;
325 info->plt_initialized = 1;
326 }
327 if (r_type == R_390_PLTOFF16 ||
328 r_type == R_390_PLTOFF32 ||
329 r_type == R_390_PLTOFF64)
330 val = me->arch.plt_offset - me->arch.got_offset +
331 info->plt_offset + rela->r_addend;
332 else {
333 if (!((r_type == R_390_PLT16DBL &&
334 val - loc + 0xffffUL < 0x1ffffeUL) ||
335 (r_type == R_390_PLT32DBL &&
336 val - loc + 0xffffffffULL < 0x1fffffffeULL)))
337 val = (Elf_Addr) me->core_layout.base +
338 me->arch.plt_offset +
339 info->plt_offset;
340 val += rela->r_addend - loc;
341 }
342 if (r_type == R_390_PLT16DBL)
343 rc = apply_rela_bits(loc, val, 1, 16, 1);
344 else if (r_type == R_390_PLTOFF16)
345 rc = apply_rela_bits(loc, val, 0, 16, 0);
346 else if (r_type == R_390_PLT32DBL)
347 rc = apply_rela_bits(loc, val, 1, 32, 1);
348 else if (r_type == R_390_PLT32 ||
349 r_type == R_390_PLTOFF32)
350 rc = apply_rela_bits(loc, val, 0, 32, 0);
351 else if (r_type == R_390_PLT64 ||
352 r_type == R_390_PLTOFF64)
353 rc = apply_rela_bits(loc, val, 0, 64, 0);
354 break;
355 case R_390_GOTOFF16: /* 16 bit offset to GOT. */
356 case R_390_GOTOFF32: /* 32 bit offset to GOT. */
357 case R_390_GOTOFF64: /* 64 bit offset to GOT. */
358 val = val + rela->r_addend -
359 ((Elf_Addr) me->core_layout.base + me->arch.got_offset);
360 if (r_type == R_390_GOTOFF16)
361 rc = apply_rela_bits(loc, val, 0, 16, 0);
362 else if (r_type == R_390_GOTOFF32)
363 rc = apply_rela_bits(loc, val, 0, 32, 0);
364 else if (r_type == R_390_GOTOFF64)
365 rc = apply_rela_bits(loc, val, 0, 64, 0);
366 break;
367 case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */
368 case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */
369 val = (Elf_Addr) me->core_layout.base + me->arch.got_offset +
370 rela->r_addend - loc;
371 if (r_type == R_390_GOTPC)
372 rc = apply_rela_bits(loc, val, 1, 32, 0);
373 else if (r_type == R_390_GOTPCDBL)
374 rc = apply_rela_bits(loc, val, 1, 32, 1);
375 break;
376 case R_390_COPY:
377 case R_390_GLOB_DAT: /* Create GOT entry. */
378 case R_390_JMP_SLOT: /* Create PLT entry. */
379 case R_390_RELATIVE: /* Adjust by program base. */
380 /* Only needed if we want to support loading of
381 modules linked with -shared. */
382 return -ENOEXEC;
383 default:
384 printk(KERN_ERR "module %s: unknown relocation: %u\n",
385 me->name, r_type);
386 return -ENOEXEC;
387 }
388 if (rc) {
389 printk(KERN_ERR "module %s: relocation error for symbol %s "
390 "(r_type %i, value 0x%lx)\n",
391 me->name, strtab + symtab[r_sym].st_name,
392 r_type, (unsigned long) val);
393 return rc;
394 }
395 return 0;
396}
397
398int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
399 unsigned int symindex, unsigned int relsec,
400 struct module *me)
401{
402 Elf_Addr base;
403 Elf_Sym *symtab;
404 Elf_Rela *rela;
405 unsigned long i, n;
406 int rc;
407
408 DEBUGP("Applying relocate section %u to %u\n",
409 relsec, sechdrs[relsec].sh_info);
410 base = sechdrs[sechdrs[relsec].sh_info].sh_addr;
411 symtab = (Elf_Sym *) sechdrs[symindex].sh_addr;
412 rela = (Elf_Rela *) sechdrs[relsec].sh_addr;
413 n = sechdrs[relsec].sh_size / sizeof(Elf_Rela);
414
415 for (i = 0; i < n; i++, rela++) {
416 rc = apply_rela(rela, base, symtab, strtab, me);
417 if (rc)
418 return rc;
419 }
420 return 0;
421}
422
423int module_finalize(const Elf_Ehdr *hdr,
424 const Elf_Shdr *sechdrs,
425 struct module *me)
426{
427 jump_label_apply_nops(me);
428 vfree(me->arch.syminfo);
429 me->arch.syminfo = NULL;
430 return 0;
431}