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