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USB: cdc-wdm: Make wdm_flush() interruptible and add wdm_fsync().
[linux/fpc-iii.git] / arch / s390 / kernel / module.c
blob9bd1933848b893a041a830e387593319831213dd
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 #include <asm/alternative.h>
35 #include <asm/nospec-branch.h>
36 #include <asm/facility.h>
37
38 #if 0
39 #define DEBUGP printk
40 #else
41 #define DEBUGP(fmt , ...)
42 #endif
43
44 #define PLT_ENTRY_SIZE 20
45
46 void *module_alloc(unsigned long size)
47 {
48 if (PAGE_ALIGN(size) > MODULES_LEN)
49 return NULL;
50 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
51 GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
52 __builtin_return_address(0));
53 }
54
55 void module_arch_freeing_init(struct module *mod)
56 {
57 vfree(mod->arch.syminfo);
58 mod->arch.syminfo = NULL;
59 }
60
61 static void check_rela(Elf_Rela *rela, struct module *me)
62 {
63 struct mod_arch_syminfo *info;
64
65 info = me->arch.syminfo + ELF_R_SYM (rela->r_info);
66 switch (ELF_R_TYPE (rela->r_info)) {
67 case R_390_GOT12: /* 12 bit GOT offset. */
68 case R_390_GOT16: /* 16 bit GOT offset. */
69 case R_390_GOT20: /* 20 bit GOT offset. */
70 case R_390_GOT32: /* 32 bit GOT offset. */
71 case R_390_GOT64: /* 64 bit GOT offset. */
72 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
73 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
74 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
75 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
76 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
77 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
78 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
79 if (info->got_offset == -1UL) {
80 info->got_offset = me->arch.got_size;
81 me->arch.got_size += sizeof(void*);
82 }
83 break;
84 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
85 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
86 case R_390_PLT32: /* 32 bit PC relative PLT address. */
87 case R_390_PLT64: /* 64 bit PC relative PLT address. */
88 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
89 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
90 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
91 if (info->plt_offset == -1UL) {
92 info->plt_offset = me->arch.plt_size;
93 me->arch.plt_size += PLT_ENTRY_SIZE;
94 }
95 break;
96 case R_390_COPY:
97 case R_390_GLOB_DAT:
98 case R_390_JMP_SLOT:
99 case R_390_RELATIVE:
100 /* Only needed if we want to support loading of
101 modules linked with -shared. */
102 break;
103 }
104 }
105
106 /*
107 * Account for GOT and PLT relocations. We can't add sections for
108 * got and plt but we can increase the core module size.
109 */
110 int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
111 char *secstrings, struct module *me)
112 {
113 Elf_Shdr *symtab;
114 Elf_Sym *symbols;
115 Elf_Rela *rela;
116 char *strings;
117 int nrela, i, j;
118
119 /* Find symbol table and string table. */
120 symtab = NULL;
121 for (i = 0; i < hdr->e_shnum; i++)
122 switch (sechdrs[i].sh_type) {
123 case SHT_SYMTAB:
124 symtab = sechdrs + i;
125 break;
126 }
127 if (!symtab) {
128 printk(KERN_ERR "module %s: no symbol table\n", me->name);
129 return -ENOEXEC;
130 }
131
132 /* Allocate one syminfo structure per symbol. */
133 me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym);
134 me->arch.syminfo = vmalloc(me->arch.nsyms *
135 sizeof(struct mod_arch_syminfo));
136 if (!me->arch.syminfo)
137 return -ENOMEM;
138 symbols = (void *) hdr + symtab->sh_offset;
139 strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset;
140 for (i = 0; i < me->arch.nsyms; i++) {
141 if (symbols[i].st_shndx == SHN_UNDEF &&
142 strcmp(strings + symbols[i].st_name,
143 "_GLOBAL_OFFSET_TABLE_") == 0)
144 /* "Define" it as absolute. */
145 symbols[i].st_shndx = SHN_ABS;
146 me->arch.syminfo[i].got_offset = -1UL;
147 me->arch.syminfo[i].plt_offset = -1UL;
148 me->arch.syminfo[i].got_initialized = 0;
149 me->arch.syminfo[i].plt_initialized = 0;
150 }
151
152 /* Search for got/plt relocations. */
153 me->arch.got_size = me->arch.plt_size = 0;
154 for (i = 0; i < hdr->e_shnum; i++) {
155 if (sechdrs[i].sh_type != SHT_RELA)
156 continue;
157 nrela = sechdrs[i].sh_size / sizeof(Elf_Rela);
158 rela = (void *) hdr + sechdrs[i].sh_offset;
159 for (j = 0; j < nrela; j++)
160 check_rela(rela + j, me);
161 }
162
163 /* Increase core size by size of got & plt and set start
164 offsets for got and plt. */
165 me->core_size = ALIGN(me->core_size, 4);
166 me->arch.got_offset = me->core_size;
167 me->core_size += me->arch.got_size;
168 me->arch.plt_offset = me->core_size;
169 if (me->arch.plt_size) {
170 if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable)
171 me->arch.plt_size += PLT_ENTRY_SIZE;
172 me->core_size += me->arch.plt_size;
173 }
174 return 0;
175 }
176
177 static int apply_rela_bits(Elf_Addr loc, Elf_Addr val,
178 int sign, int bits, int shift)
179 {
180 unsigned long umax;
181 long min, max;
182
183 if (val & ((1UL << shift) - 1))
184 return -ENOEXEC;
185 if (sign) {
186 val = (Elf_Addr)(((long) val) >> shift);
187 min = -(1L << (bits - 1));
188 max = (1L << (bits - 1)) - 1;
189 if ((long) val < min || (long) val > max)
190 return -ENOEXEC;
191 } else {
192 val >>= shift;
193 umax = ((1UL << (bits - 1)) << 1) - 1;
194 if ((unsigned long) val > umax)
195 return -ENOEXEC;
196 }
197
198 if (bits == 8)
199 *(unsigned char *) loc = val;
200 else if (bits == 12)
201 *(unsigned short *) loc = (val & 0xfff) |
202 (*(unsigned short *) loc & 0xf000);
203 else if (bits == 16)
204 *(unsigned short *) loc = val;
205 else if (bits == 20)
206 *(unsigned int *) loc = (val & 0xfff) << 16 |
207 (val & 0xff000) >> 4 |
208 (*(unsigned int *) loc & 0xf00000ff);
209 else if (bits == 32)
210 *(unsigned int *) loc = val;
211 else if (bits == 64)
212 *(unsigned long *) loc = val;
213 return 0;
214 }
215
216 static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
217 const char *strtab, struct module *me)
218 {
219 struct mod_arch_syminfo *info;
220 Elf_Addr loc, val;
221 int r_type, r_sym;
222 int rc = -ENOEXEC;
223
224 /* This is where to make the change */
225 loc = base + rela->r_offset;
226 /* This is the symbol it is referring to. Note that all
227 undefined symbols have been resolved. */
228 r_sym = ELF_R_SYM(rela->r_info);
229 r_type = ELF_R_TYPE(rela->r_info);
230 info = me->arch.syminfo + r_sym;
231 val = symtab[r_sym].st_value;
232
233 switch (r_type) {
234 case R_390_NONE: /* No relocation. */
235 rc = 0;
236 break;
237 case R_390_8: /* Direct 8 bit. */
238 case R_390_12: /* Direct 12 bit. */
239 case R_390_16: /* Direct 16 bit. */
240 case R_390_20: /* Direct 20 bit. */
241 case R_390_32: /* Direct 32 bit. */
242 case R_390_64: /* Direct 64 bit. */
243 val += rela->r_addend;
244 if (r_type == R_390_8)
245 rc = apply_rela_bits(loc, val, 0, 8, 0);
246 else if (r_type == R_390_12)
247 rc = apply_rela_bits(loc, val, 0, 12, 0);
248 else if (r_type == R_390_16)
249 rc = apply_rela_bits(loc, val, 0, 16, 0);
250 else if (r_type == R_390_20)
251 rc = apply_rela_bits(loc, val, 1, 20, 0);
252 else if (r_type == R_390_32)
253 rc = apply_rela_bits(loc, val, 0, 32, 0);
254 else if (r_type == R_390_64)
255 rc = apply_rela_bits(loc, val, 0, 64, 0);
256 break;
257 case R_390_PC16: /* PC relative 16 bit. */
258 case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */
259 case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */
260 case R_390_PC32: /* PC relative 32 bit. */
261 case R_390_PC64: /* PC relative 64 bit. */
262 val += rela->r_addend - loc;
263 if (r_type == R_390_PC16)
264 rc = apply_rela_bits(loc, val, 1, 16, 0);
265 else if (r_type == R_390_PC16DBL)
266 rc = apply_rela_bits(loc, val, 1, 16, 1);
267 else if (r_type == R_390_PC32DBL)
268 rc = apply_rela_bits(loc, val, 1, 32, 1);
269 else if (r_type == R_390_PC32)
270 rc = apply_rela_bits(loc, val, 1, 32, 0);
271 else if (r_type == R_390_PC64)
272 rc = apply_rela_bits(loc, val, 1, 64, 0);
273 break;
274 case R_390_GOT12: /* 12 bit GOT offset. */
275 case R_390_GOT16: /* 16 bit GOT offset. */
276 case R_390_GOT20: /* 20 bit GOT offset. */
277 case R_390_GOT32: /* 32 bit GOT offset. */
278 case R_390_GOT64: /* 64 bit GOT offset. */
279 case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
280 case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
281 case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
282 case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
283 case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
284 case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
285 case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
286 if (info->got_initialized == 0) {
287 Elf_Addr *gotent;
288
289 gotent = me->module_core + me->arch.got_offset +
290 info->got_offset;
291 *gotent = val;
292 info->got_initialized = 1;
293 }
294 val = info->got_offset + rela->r_addend;
295 if (r_type == R_390_GOT12 ||
296 r_type == R_390_GOTPLT12)
297 rc = apply_rela_bits(loc, val, 0, 12, 0);
298 else if (r_type == R_390_GOT16 ||
299 r_type == R_390_GOTPLT16)
300 rc = apply_rela_bits(loc, val, 0, 16, 0);
301 else if (r_type == R_390_GOT20 ||
302 r_type == R_390_GOTPLT20)
303 rc = apply_rela_bits(loc, val, 1, 20, 0);
304 else if (r_type == R_390_GOT32 ||
305 r_type == R_390_GOTPLT32)
306 rc = apply_rela_bits(loc, val, 0, 32, 0);
307 else if (r_type == R_390_GOT64 ||
308 r_type == R_390_GOTPLT64)
309 rc = apply_rela_bits(loc, val, 0, 64, 0);
310 else if (r_type == R_390_GOTENT ||
311 r_type == R_390_GOTPLTENT) {
312 val += (Elf_Addr) me->module_core - loc;
313 rc = apply_rela_bits(loc, val, 1, 32, 1);
314 }
315 break;
316 case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
317 case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
318 case R_390_PLT32: /* 32 bit PC relative PLT address. */
319 case R_390_PLT64: /* 64 bit PC relative PLT address. */
320 case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
321 case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
322 case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
323 if (info->plt_initialized == 0) {
324 unsigned int *ip;
325 ip = me->module_core + me->arch.plt_offset +
326 info->plt_offset;
327 ip[0] = 0x0d10e310; /* basr 1,0 */
328 ip[1] = 0x100a0004; /* lg 1,10(1) */
329 if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable) {
330 unsigned int *ij;
331 ij = me->module_core +
332 me->arch.plt_offset +
333 me->arch.plt_size - PLT_ENTRY_SIZE;
334 ip[2] = 0xa7f40000 + /* j __jump_r1 */
335 (unsigned int)(u16)
336 (((unsigned long) ij - 8 -
337 (unsigned long) ip) / 2);
338 } else {
339 ip[2] = 0x07f10000; /* br %r1 */
340 }
341 ip[3] = (unsigned int) (val >> 32);
342 ip[4] = (unsigned int) val;
343 info->plt_initialized = 1;
344 }
345 if (r_type == R_390_PLTOFF16 ||
346 r_type == R_390_PLTOFF32 ||
347 r_type == R_390_PLTOFF64)
348 val = me->arch.plt_offset - me->arch.got_offset +
349 info->plt_offset + rela->r_addend;
350 else {
351 if (!((r_type == R_390_PLT16DBL &&
352 val - loc + 0xffffUL < 0x1ffffeUL) ||
353 (r_type == R_390_PLT32DBL &&
354 val - loc + 0xffffffffULL < 0x1fffffffeULL)))
355 val = (Elf_Addr) me->module_core +
356 me->arch.plt_offset +
357 info->plt_offset;
358 val += rela->r_addend - loc;
359 }
360 if (r_type == R_390_PLT16DBL)
361 rc = apply_rela_bits(loc, val, 1, 16, 1);
362 else if (r_type == R_390_PLTOFF16)
363 rc = apply_rela_bits(loc, val, 0, 16, 0);
364 else if (r_type == R_390_PLT32DBL)
365 rc = apply_rela_bits(loc, val, 1, 32, 1);
366 else if (r_type == R_390_PLT32 ||
367 r_type == R_390_PLTOFF32)
368 rc = apply_rela_bits(loc, val, 0, 32, 0);
369 else if (r_type == R_390_PLT64 ||
370 r_type == R_390_PLTOFF64)
371 rc = apply_rela_bits(loc, val, 0, 64, 0);
372 break;
373 case R_390_GOTOFF16: /* 16 bit offset to GOT. */
374 case R_390_GOTOFF32: /* 32 bit offset to GOT. */
375 case R_390_GOTOFF64: /* 64 bit offset to GOT. */
376 val = val + rela->r_addend -
377 ((Elf_Addr) me->module_core + me->arch.got_offset);
378 if (r_type == R_390_GOTOFF16)
379 rc = apply_rela_bits(loc, val, 0, 16, 0);
380 else if (r_type == R_390_GOTOFF32)
381 rc = apply_rela_bits(loc, val, 0, 32, 0);
382 else if (r_type == R_390_GOTOFF64)
383 rc = apply_rela_bits(loc, val, 0, 64, 0);
384 break;
385 case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */
386 case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */
387 val = (Elf_Addr) me->module_core + me->arch.got_offset +
388 rela->r_addend - loc;
389 if (r_type == R_390_GOTPC)
390 rc = apply_rela_bits(loc, val, 1, 32, 0);
391 else if (r_type == R_390_GOTPCDBL)
392 rc = apply_rela_bits(loc, val, 1, 32, 1);
393 break;
394 case R_390_COPY:
395 case R_390_GLOB_DAT: /* Create GOT entry. */
396 case R_390_JMP_SLOT: /* Create PLT entry. */
397 case R_390_RELATIVE: /* Adjust by program base. */
398 /* Only needed if we want to support loading of
399 modules linked with -shared. */
400 return -ENOEXEC;
401 default:
402 printk(KERN_ERR "module %s: unknown relocation: %u\n",
403 me->name, r_type);
404 return -ENOEXEC;
405 }
406 if (rc) {
407 printk(KERN_ERR "module %s: relocation error for symbol %s "
408 "(r_type %i, value 0x%lx)\n",
409 me->name, strtab + symtab[r_sym].st_name,
410 r_type, (unsigned long) val);
411 return rc;
412 }
413 return 0;
414 }
415
416 int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
417 unsigned int symindex, unsigned int relsec,
418 struct module *me)
419 {
420 Elf_Addr base;
421 Elf_Sym *symtab;
422 Elf_Rela *rela;
423 unsigned long i, n;
424 int rc;
425
426 DEBUGP("Applying relocate section %u to %u\n",
427 relsec, sechdrs[relsec].sh_info);
428 base = sechdrs[sechdrs[relsec].sh_info].sh_addr;
429 symtab = (Elf_Sym *) sechdrs[symindex].sh_addr;
430 rela = (Elf_Rela *) sechdrs[relsec].sh_addr;
431 n = sechdrs[relsec].sh_size / sizeof(Elf_Rela);
432
433 for (i = 0; i < n; i++, rela++) {
434 rc = apply_rela(rela, base, symtab, strtab, me);
435 if (rc)
436 return rc;
437 }
438 return 0;
439 }
440
441 int module_finalize(const Elf_Ehdr *hdr,
442 const Elf_Shdr *sechdrs,
443 struct module *me)
444 {
445 const Elf_Shdr *s;
446 char *secstrings, *secname;
447 void *aseg;
448
449 if (IS_ENABLED(CONFIG_EXPOLINE) &&
450 !nospec_disable && me->arch.plt_size) {
451 unsigned int *ij;
452
453 ij = me->module_core + me->arch.plt_offset +
454 me->arch.plt_size - PLT_ENTRY_SIZE;
455 if (test_facility(35)) {
456 ij[0] = 0xc6000000; /* exrl %r0,.+10 */
457 ij[1] = 0x0005a7f4; /* j . */
458 ij[2] = 0x000007f1; /* br %r1 */
459 } else {
460 ij[0] = 0x44000000 | (unsigned int)
461 offsetof(struct _lowcore, br_r1_trampoline);
462 ij[1] = 0xa7f40000; /* j . */
463 }
464 }
465
466 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
467 for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
468 aseg = (void *) s->sh_addr;
469 secname = secstrings + s->sh_name;
470
471 if (!strcmp(".altinstructions", secname))
472 /* patch .altinstructions */
473 apply_alternatives(aseg, aseg + s->sh_size);
474
475 if (IS_ENABLED(CONFIG_EXPOLINE) &&
476 (!strncmp(".s390_indirect", secname, 14)))
477 nospec_revert(aseg, aseg + s->sh_size);
478
479 if (IS_ENABLED(CONFIG_EXPOLINE) &&
480 (!strncmp(".s390_return", secname, 12)))
481 nospec_revert(aseg, aseg + s->sh_size);
482 }
483
484 jump_label_apply_nops(me);
485 vfree(me->arch.syminfo);
486 me->arch.syminfo = NULL;
487 return 0;
488 }
Linux with added FPC-III support