1 /* Kernel dynamically loadable module help for PARISC. 2 * 3 * The best reference for this stuff is probably the Processor- 4 * Specific ELF Supplement for PA-RISC: 5 * http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf 6 * 7 * Linux/PA-RISC Project (http://www.parisc-linux.org/) 8 * Copyright (C) 2003 Randolph Chung <tausq at debian . org> 9 * 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 24 * 25 * 26 * Notes: 27 * - SEGREL32 handling 28 * We are not doing SEGREL32 handling correctly. According to the ABI, we 29 * should do a value offset, like this: 30 * if (in_init(me, (void *)val)) 31 * val -= (uint32_t)me->module_init; 32 * else 33 * val -= (uint32_t)me->module_core; 34 * However, SEGREL32 is used only for PARISC unwind entries, and we want 35 * those entries to have an absolute address, and not just an offset. 36 * 37 * The unwind table mechanism has the ability to specify an offset for 38 * the unwind table; however, because we split off the init functions into 39 * a different piece of memory, it is not possible to do this using a 40 * single offset. Instead, we use the above hack for now. 41 */ 42 43 #include <linux/moduleloader.h> 44 #include <linux/elf.h> 45 #include <linux/vmalloc.h> 46 #include <linux/fs.h> 47 #include <linux/string.h> 48 #include <linux/kernel.h> 49 #include <linux/bug.h> 50 51 #include <asm/unwind.h> 52 53 #if 0 54 #define DEBUGP printk 55 #else 56 #define DEBUGP(fmt...) 57 #endif 58 59 #define CHECK_RELOC(val, bits) \ 60 if ( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \ 61 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) { \ 62 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \ 63 me->name, strtab + sym->st_name, (unsigned long)val, bits); \ 64 return -ENOEXEC; \ 65 } 66 67 /* Maximum number of GOT entries. We use a long displacement ldd from 68 * the bottom of the table, which has a maximum signed displacement of 69 * 0x3fff; however, since we're only going forward, this becomes 70 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have 71 * at most 1023 entries */ 72 #define MAX_GOTS 1023 73 74 /* three functions to determine where in the module core 75 * or init pieces the location is */ 76 static inline int in_init(struct module *me, void *loc) 77 { 78 return (loc >= me->module_init && 79 loc <= (me->module_init + me->init_size)); 80 } 81 82 static inline int in_core(struct module *me, void *loc) 83 { 84 return (loc >= me->module_core && 85 loc <= (me->module_core + me->core_size)); 86 } 87 88 static inline int in_local(struct module *me, void *loc) 89 { 90 return in_init(me, loc) || in_core(me, loc); 91 } 92 93 static inline int in_local_section(struct module *me, void *loc, void *dot) 94 { 95 return (in_init(me, loc) && in_init(me, dot)) || 96 (in_core(me, loc) && in_core(me, dot)); 97 } 98 99 100 #ifndef CONFIG_64BIT 101 struct got_entry { 102 Elf32_Addr addr; 103 }; 104 105 #define Elf_Fdesc Elf32_Fdesc 106 107 struct stub_entry { 108 Elf32_Word insns[2]; /* each stub entry has two insns */ 109 }; 110 #else 111 struct got_entry { 112 Elf64_Addr addr; 113 }; 114 115 #define Elf_Fdesc Elf64_Fdesc 116 117 struct stub_entry { 118 Elf64_Word insns[4]; /* each stub entry has four insns */ 119 }; 120 #endif 121 122 /* Field selection types defined by hppa */ 123 #define rnd(x) (((x)+0x1000)&~0x1fff) 124 /* fsel: full 32 bits */ 125 #define fsel(v,a) ((v)+(a)) 126 /* lsel: select left 21 bits */ 127 #define lsel(v,a) (((v)+(a))>>11) 128 /* rsel: select right 11 bits */ 129 #define rsel(v,a) (((v)+(a))&0x7ff) 130 /* lrsel with rounding of addend to nearest 8k */ 131 #define lrsel(v,a) (((v)+rnd(a))>>11) 132 /* rrsel with rounding of addend to nearest 8k */ 133 #define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a))) 134 135 #define mask(x,sz) ((x) & ~((1<<(sz))-1)) 136 137 138 /* The reassemble_* functions prepare an immediate value for 139 insertion into an opcode. pa-risc uses all sorts of weird bitfields 140 in the instruction to hold the value. */ 141 static inline int reassemble_14(int as14) 142 { 143 return (((as14 & 0x1fff) << 1) | 144 ((as14 & 0x2000) >> 13)); 145 } 146 147 static inline int reassemble_17(int as17) 148 { 149 return (((as17 & 0x10000) >> 16) | 150 ((as17 & 0x0f800) << 5) | 151 ((as17 & 0x00400) >> 8) | 152 ((as17 & 0x003ff) << 3)); 153 } 154 155 static inline int reassemble_21(int as21) 156 { 157 return (((as21 & 0x100000) >> 20) | 158 ((as21 & 0x0ffe00) >> 8) | 159 ((as21 & 0x000180) << 7) | 160 ((as21 & 0x00007c) << 14) | 161 ((as21 & 0x000003) << 12)); 162 } 163 164 static inline int reassemble_22(int as22) 165 { 166 return (((as22 & 0x200000) >> 21) | 167 ((as22 & 0x1f0000) << 5) | 168 ((as22 & 0x00f800) << 5) | 169 ((as22 & 0x000400) >> 8) | 170 ((as22 & 0x0003ff) << 3)); 171 } 172 173 void *module_alloc(unsigned long size) 174 { 175 if (size == 0) 176 return NULL; 177 return vmalloc(size); 178 } 179 180 #ifndef CONFIG_64BIT 181 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 182 { 183 return 0; 184 } 185 186 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 187 { 188 return 0; 189 } 190 191 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 192 { 193 unsigned long cnt = 0; 194 195 for (; n > 0; n--, rela++) 196 { 197 switch (ELF32_R_TYPE(rela->r_info)) { 198 case R_PARISC_PCREL17F: 199 case R_PARISC_PCREL22F: 200 cnt++; 201 } 202 } 203 204 return cnt; 205 } 206 #else 207 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 208 { 209 unsigned long cnt = 0; 210 211 for (; n > 0; n--, rela++) 212 { 213 switch (ELF64_R_TYPE(rela->r_info)) { 214 case R_PARISC_LTOFF21L: 215 case R_PARISC_LTOFF14R: 216 case R_PARISC_PCREL22F: 217 cnt++; 218 } 219 } 220 221 return cnt; 222 } 223 224 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 225 { 226 unsigned long cnt = 0; 227 228 for (; n > 0; n--, rela++) 229 { 230 switch (ELF64_R_TYPE(rela->r_info)) { 231 case R_PARISC_FPTR64: 232 cnt++; 233 } 234 } 235 236 return cnt; 237 } 238 239 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 240 { 241 unsigned long cnt = 0; 242 243 for (; n > 0; n--, rela++) 244 { 245 switch (ELF64_R_TYPE(rela->r_info)) { 246 case R_PARISC_PCREL22F: 247 cnt++; 248 } 249 } 250 251 return cnt; 252 } 253 #endif 254 255 256 /* Free memory returned from module_alloc */ 257 void module_free(struct module *mod, void *module_region) 258 { 259 vfree(module_region); 260 /* FIXME: If module_region == mod->init_region, trim exception 261 table entries. */ 262 } 263 264 #define CONST 265 int module_frob_arch_sections(CONST Elf_Ehdr *hdr, 266 CONST Elf_Shdr *sechdrs, 267 CONST char *secstrings, 268 struct module *me) 269 { 270 unsigned long gots = 0, fdescs = 0, stubs = 0, init_stubs = 0; 271 unsigned int i; 272 273 for (i = 1; i < hdr->e_shnum; i++) { 274 const Elf_Rela *rels = (void *)hdr + sechdrs[i].sh_offset; 275 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels); 276 277 if (strncmp(secstrings + sechdrs[i].sh_name, 278 ".PARISC.unwind", 14) == 0) 279 me->arch.unwind_section = i; 280 281 if (sechdrs[i].sh_type != SHT_RELA) 282 continue; 283 284 /* some of these are not relevant for 32-bit/64-bit 285 * we leave them here to make the code common. the 286 * compiler will do its thing and optimize out the 287 * stuff we don't need 288 */ 289 gots += count_gots(rels, nrels); 290 fdescs += count_fdescs(rels, nrels); 291 if(strncmp(secstrings + sechdrs[i].sh_name, 292 ".rela.init", 10) == 0) 293 init_stubs += count_stubs(rels, nrels); 294 else 295 stubs += count_stubs(rels, nrels); 296 } 297 298 /* align things a bit */ 299 me->core_size = ALIGN(me->core_size, 16); 300 me->arch.got_offset = me->core_size; 301 me->core_size += gots * sizeof(struct got_entry); 302 303 me->core_size = ALIGN(me->core_size, 16); 304 me->arch.fdesc_offset = me->core_size; 305 me->core_size += fdescs * sizeof(Elf_Fdesc); 306 307 me->core_size = ALIGN(me->core_size, 16); 308 me->arch.stub_offset = me->core_size; 309 me->core_size += stubs * sizeof(struct stub_entry); 310 311 me->init_size = ALIGN(me->init_size, 16); 312 me->arch.init_stub_offset = me->init_size; 313 me->init_size += init_stubs * sizeof(struct stub_entry); 314 315 me->arch.got_max = gots; 316 me->arch.fdesc_max = fdescs; 317 me->arch.stub_max = stubs; 318 me->arch.init_stub_max = init_stubs; 319 320 return 0; 321 } 322 323 #ifdef CONFIG_64BIT 324 static Elf64_Word get_got(struct module *me, unsigned long value, long addend) 325 { 326 unsigned int i; 327 struct got_entry *got; 328 329 value += addend; 330 331 BUG_ON(value == 0); 332 333 got = me->module_core + me->arch.got_offset; 334 for (i = 0; got[i].addr; i++) 335 if (got[i].addr == value) 336 goto out; 337 338 BUG_ON(++me->arch.got_count > me->arch.got_max); 339 340 got[i].addr = value; 341 out: 342 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry), 343 value); 344 return i * sizeof(struct got_entry); 345 } 346 #endif /* CONFIG_64BIT */ 347 348 #ifdef CONFIG_64BIT 349 static Elf_Addr get_fdesc(struct module *me, unsigned long value) 350 { 351 Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset; 352 353 if (!value) { 354 printk(KERN_ERR "%s: zero OPD requested!\n", me->name); 355 return 0; 356 } 357 358 /* Look for existing fdesc entry. */ 359 while (fdesc->addr) { 360 if (fdesc->addr == value) 361 return (Elf_Addr)fdesc; 362 fdesc++; 363 } 364 365 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max); 366 367 /* Create new one */ 368 fdesc->addr = value; 369 fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset; 370 return (Elf_Addr)fdesc; 371 } 372 #endif /* CONFIG_64BIT */ 373 374 enum elf_stub_type { 375 ELF_STUB_GOT, 376 ELF_STUB_MILLI, 377 ELF_STUB_DIRECT, 378 }; 379 380 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend, 381 enum elf_stub_type stub_type, int init_section) 382 { 383 unsigned long i; 384 struct stub_entry *stub; 385 386 if(init_section) { 387 i = me->arch.init_stub_count++; 388 BUG_ON(me->arch.init_stub_count > me->arch.init_stub_max); 389 stub = me->module_init + me->arch.init_stub_offset + 390 i * sizeof(struct stub_entry); 391 } else { 392 i = me->arch.stub_count++; 393 BUG_ON(me->arch.stub_count > me->arch.stub_max); 394 stub = me->module_core + me->arch.stub_offset + 395 i * sizeof(struct stub_entry); 396 } 397 398 #ifndef CONFIG_64BIT 399 /* for 32-bit the stub looks like this: 400 * ldil L'XXX,%r1 401 * be,n R'XXX(%sr4,%r1) 402 */ 403 //value = *(unsigned long *)((value + addend) & ~3); /* why? */ 404 405 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */ 406 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */ 407 408 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 409 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4); 410 411 #else 412 /* for 64-bit we have three kinds of stubs: 413 * for normal function calls: 414 * ldd 0(%dp),%dp 415 * ldd 10(%dp), %r1 416 * bve (%r1) 417 * ldd 18(%dp), %dp 418 * 419 * for millicode: 420 * ldil 0, %r1 421 * ldo 0(%r1), %r1 422 * ldd 10(%r1), %r1 423 * bve,n (%r1) 424 * 425 * for direct branches (jumps between different section of the 426 * same module): 427 * ldil 0, %r1 428 * ldo 0(%r1), %r1 429 * bve,n (%r1) 430 */ 431 switch (stub_type) { 432 case ELF_STUB_GOT: 433 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */ 434 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */ 435 stub->insns[2] = 0xe820d000; /* bve (%r1) */ 436 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */ 437 438 stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff); 439 break; 440 case ELF_STUB_MILLI: 441 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 442 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 443 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */ 444 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */ 445 446 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 447 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 448 break; 449 case ELF_STUB_DIRECT: 450 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 451 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 452 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */ 453 454 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 455 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 456 break; 457 } 458 459 #endif 460 461 return (Elf_Addr)stub; 462 } 463 464 int apply_relocate(Elf_Shdr *sechdrs, 465 const char *strtab, 466 unsigned int symindex, 467 unsigned int relsec, 468 struct module *me) 469 { 470 /* parisc should not need this ... */ 471 printk(KERN_ERR "module %s: RELOCATION unsupported\n", 472 me->name); 473 return -ENOEXEC; 474 } 475 476 #ifndef CONFIG_64BIT 477 int apply_relocate_add(Elf_Shdr *sechdrs, 478 const char *strtab, 479 unsigned int symindex, 480 unsigned int relsec, 481 struct module *me) 482 { 483 int i; 484 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 485 Elf32_Sym *sym; 486 Elf32_Word *loc; 487 Elf32_Addr val; 488 Elf32_Sword addend; 489 Elf32_Addr dot; 490 //unsigned long dp = (unsigned long)$global$; 491 register unsigned long dp asm ("r27"); 492 493 DEBUGP("Applying relocate section %u to %u\n", relsec, 494 sechdrs[relsec].sh_info); 495 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 496 /* This is where to make the change */ 497 loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 498 + rel[i].r_offset; 499 /* This is the symbol it is referring to */ 500 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 501 + ELF32_R_SYM(rel[i].r_info); 502 if (!sym->st_value) { 503 printk(KERN_WARNING "%s: Unknown symbol %s\n", 504 me->name, strtab + sym->st_name); 505 return -ENOENT; 506 } 507 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 508 dot = (Elf32_Addr)loc & ~0x03; 509 510 val = sym->st_value; 511 addend = rel[i].r_addend; 512 513 #if 0 514 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t : 515 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n", 516 strtab + sym->st_name, 517 (uint32_t)loc, val, addend, 518 r(R_PARISC_PLABEL32) 519 r(R_PARISC_DIR32) 520 r(R_PARISC_DIR21L) 521 r(R_PARISC_DIR14R) 522 r(R_PARISC_SEGREL32) 523 r(R_PARISC_DPREL21L) 524 r(R_PARISC_DPREL14R) 525 r(R_PARISC_PCREL17F) 526 r(R_PARISC_PCREL22F) 527 "UNKNOWN"); 528 #undef r 529 #endif 530 531 switch (ELF32_R_TYPE(rel[i].r_info)) { 532 case R_PARISC_PLABEL32: 533 /* 32-bit function address */ 534 /* no function descriptors... */ 535 *loc = fsel(val, addend); 536 break; 537 case R_PARISC_DIR32: 538 /* direct 32-bit ref */ 539 *loc = fsel(val, addend); 540 break; 541 case R_PARISC_DIR21L: 542 /* left 21 bits of effective address */ 543 val = lrsel(val, addend); 544 *loc = mask(*loc, 21) | reassemble_21(val); 545 break; 546 case R_PARISC_DIR14R: 547 /* right 14 bits of effective address */ 548 val = rrsel(val, addend); 549 *loc = mask(*loc, 14) | reassemble_14(val); 550 break; 551 case R_PARISC_SEGREL32: 552 /* 32-bit segment relative address */ 553 /* See note about special handling of SEGREL32 at 554 * the beginning of this file. 555 */ 556 *loc = fsel(val, addend); 557 break; 558 case R_PARISC_DPREL21L: 559 /* left 21 bit of relative address */ 560 val = lrsel(val - dp, addend); 561 *loc = mask(*loc, 21) | reassemble_21(val); 562 break; 563 case R_PARISC_DPREL14R: 564 /* right 14 bit of relative address */ 565 val = rrsel(val - dp, addend); 566 *loc = mask(*loc, 14) | reassemble_14(val); 567 break; 568 case R_PARISC_PCREL17F: 569 /* 17-bit PC relative address */ 570 val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc)); 571 val = (val - dot - 8)/4; 572 CHECK_RELOC(val, 17) 573 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val); 574 break; 575 case R_PARISC_PCREL22F: 576 /* 22-bit PC relative address; only defined for pa20 */ 577 val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc)); 578 DEBUGP("STUB FOR %s loc %lx+%lx at %lx\n", 579 strtab + sym->st_name, (unsigned long)loc, addend, 580 val) 581 val = (val - dot - 8)/4; 582 CHECK_RELOC(val, 22); 583 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 584 break; 585 586 default: 587 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 588 me->name, ELF32_R_TYPE(rel[i].r_info)); 589 return -ENOEXEC; 590 } 591 } 592 593 return 0; 594 } 595 596 #else 597 int apply_relocate_add(Elf_Shdr *sechdrs, 598 const char *strtab, 599 unsigned int symindex, 600 unsigned int relsec, 601 struct module *me) 602 { 603 int i; 604 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; 605 Elf64_Sym *sym; 606 Elf64_Word *loc; 607 Elf64_Xword *loc64; 608 Elf64_Addr val; 609 Elf64_Sxword addend; 610 Elf64_Addr dot; 611 612 DEBUGP("Applying relocate section %u to %u\n", relsec, 613 sechdrs[relsec].sh_info); 614 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 615 /* This is where to make the change */ 616 loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 617 + rel[i].r_offset; 618 /* This is the symbol it is referring to */ 619 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr 620 + ELF64_R_SYM(rel[i].r_info); 621 if (!sym->st_value) { 622 printk(KERN_WARNING "%s: Unknown symbol %s\n", 623 me->name, strtab + sym->st_name); 624 return -ENOENT; 625 } 626 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 627 dot = (Elf64_Addr)loc & ~0x03; 628 loc64 = (Elf64_Xword *)loc; 629 630 val = sym->st_value; 631 addend = rel[i].r_addend; 632 633 #if 0 634 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t : 635 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n", 636 strtab + sym->st_name, 637 loc, val, addend, 638 r(R_PARISC_LTOFF14R) 639 r(R_PARISC_LTOFF21L) 640 r(R_PARISC_PCREL22F) 641 r(R_PARISC_DIR64) 642 r(R_PARISC_SEGREL32) 643 r(R_PARISC_FPTR64) 644 "UNKNOWN"); 645 #undef r 646 #endif 647 648 switch (ELF64_R_TYPE(rel[i].r_info)) { 649 case R_PARISC_LTOFF21L: 650 /* LT-relative; left 21 bits */ 651 val = get_got(me, val, addend); 652 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n", 653 strtab + sym->st_name, 654 loc, val); 655 val = lrsel(val, 0); 656 *loc = mask(*loc, 21) | reassemble_21(val); 657 break; 658 case R_PARISC_LTOFF14R: 659 /* L(ltoff(val+addend)) */ 660 /* LT-relative; right 14 bits */ 661 val = get_got(me, val, addend); 662 val = rrsel(val, 0); 663 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n", 664 strtab + sym->st_name, 665 loc, val); 666 *loc = mask(*loc, 14) | reassemble_14(val); 667 break; 668 case R_PARISC_PCREL22F: 669 /* PC-relative; 22 bits */ 670 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n", 671 strtab + sym->st_name, 672 loc, val); 673 /* can we reach it locally? */ 674 if(!in_local_section(me, (void *)val, (void *)dot)) { 675 676 if (in_local(me, (void *)val)) 677 /* this is the case where the 678 * symbol is local to the 679 * module, but in a different 680 * section, so stub the jump 681 * in case it's more than 22 682 * bits away */ 683 val = get_stub(me, val, addend, ELF_STUB_DIRECT, 684 in_init(me, loc)); 685 else if (strncmp(strtab + sym->st_name, "$$", 2) 686 == 0) 687 val = get_stub(me, val, addend, ELF_STUB_MILLI, 688 in_init(me, loc)); 689 else 690 val = get_stub(me, val, addend, ELF_STUB_GOT, 691 in_init(me, loc)); 692 } 693 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 694 strtab + sym->st_name, loc, sym->st_value, 695 addend, val); 696 /* FIXME: local symbols work as long as the 697 * core and init pieces aren't separated too 698 * far. If this is ever broken, you will trip 699 * the check below. The way to fix it would 700 * be to generate local stubs to go between init 701 * and core */ 702 if((Elf64_Sxword)(val - dot - 8) > 0x800000 -1 || 703 (Elf64_Sxword)(val - dot - 8) < -0x800000) { 704 printk(KERN_ERR "Module %s, symbol %s is out of range for PCREL22F relocation\n", 705 me->name, strtab + sym->st_name); 706 return -ENOEXEC; 707 } 708 val = (val - dot - 8)/4; 709 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 710 break; 711 case R_PARISC_DIR64: 712 /* 64-bit effective address */ 713 *loc64 = val + addend; 714 break; 715 case R_PARISC_SEGREL32: 716 /* 32-bit segment relative address */ 717 /* See note about special handling of SEGREL32 at 718 * the beginning of this file. 719 */ 720 *loc = fsel(val, addend); 721 break; 722 case R_PARISC_FPTR64: 723 /* 64-bit function address */ 724 if(in_local(me, (void *)(val + addend))) { 725 *loc64 = get_fdesc(me, val+addend); 726 DEBUGP("FDESC for %s at %p points to %lx\n", 727 strtab + sym->st_name, *loc64, 728 ((Elf_Fdesc *)*loc64)->addr); 729 } else { 730 /* if the symbol is not local to this 731 * module then val+addend is a pointer 732 * to the function descriptor */ 733 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n", 734 strtab + sym->st_name, 735 loc, val); 736 *loc64 = val + addend; 737 } 738 break; 739 740 default: 741 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n", 742 me->name, ELF64_R_TYPE(rel[i].r_info)); 743 return -ENOEXEC; 744 } 745 } 746 return 0; 747 } 748 #endif 749 750 static void 751 register_unwind_table(struct module *me, 752 const Elf_Shdr *sechdrs) 753 { 754 unsigned char *table, *end; 755 unsigned long gp; 756 757 if (!me->arch.unwind_section) 758 return; 759 760 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr; 761 end = table + sechdrs[me->arch.unwind_section].sh_size; 762 gp = (Elf_Addr)me->module_core + me->arch.got_offset; 763 764 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n", 765 me->arch.unwind_section, table, end, gp); 766 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end); 767 } 768 769 static void 770 deregister_unwind_table(struct module *me) 771 { 772 if (me->arch.unwind) 773 unwind_table_remove(me->arch.unwind); 774 } 775 776 int module_finalize(const Elf_Ehdr *hdr, 777 const Elf_Shdr *sechdrs, 778 struct module *me) 779 { 780 int i; 781 unsigned long nsyms; 782 const char *strtab = NULL; 783 Elf_Sym *newptr, *oldptr; 784 Elf_Shdr *symhdr = NULL; 785 #ifdef DEBUG 786 Elf_Fdesc *entry; 787 u32 *addr; 788 789 entry = (Elf_Fdesc *)me->init; 790 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry, 791 entry->gp, entry->addr); 792 addr = (u32 *)entry->addr; 793 printk("INSNS: %x %x %x %x\n", 794 addr[0], addr[1], addr[2], addr[3]); 795 printk("stubs used %ld, stubs max %ld\n" 796 "init_stubs used %ld, init stubs max %ld\n" 797 "got entries used %ld, gots max %ld\n" 798 "fdescs used %ld, fdescs max %ld\n", 799 me->arch.stub_count, me->arch.stub_max, 800 me->arch.init_stub_count, me->arch.init_stub_max, 801 me->arch.got_count, me->arch.got_max, 802 me->arch.fdesc_count, me->arch.fdesc_max); 803 #endif 804 805 register_unwind_table(me, sechdrs); 806 807 /* haven't filled in me->symtab yet, so have to find it 808 * ourselves */ 809 for (i = 1; i < hdr->e_shnum; i++) { 810 if(sechdrs[i].sh_type == SHT_SYMTAB 811 && (sechdrs[i].sh_type & SHF_ALLOC)) { 812 int strindex = sechdrs[i].sh_link; 813 /* FIXME: AWFUL HACK 814 * The cast is to drop the const from 815 * the sechdrs pointer */ 816 symhdr = (Elf_Shdr *)&sechdrs[i]; 817 strtab = (char *)sechdrs[strindex].sh_addr; 818 break; 819 } 820 } 821 822 DEBUGP("module %s: strtab %p, symhdr %p\n", 823 me->name, strtab, symhdr); 824 825 if(me->arch.got_count > MAX_GOTS) { 826 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n", 827 me->name, me->arch.got_count, MAX_GOTS); 828 return -EINVAL; 829 } 830 831 /* no symbol table */ 832 if(symhdr == NULL) 833 return 0; 834 835 oldptr = (void *)symhdr->sh_addr; 836 newptr = oldptr + 1; /* we start counting at 1 */ 837 nsyms = symhdr->sh_size / sizeof(Elf_Sym); 838 DEBUGP("OLD num_symtab %lu\n", nsyms); 839 840 for (i = 1; i < nsyms; i++) { 841 oldptr++; /* note, count starts at 1 so preincrement */ 842 if(strncmp(strtab + oldptr->st_name, 843 ".L", 2) == 0) 844 continue; 845 846 if(newptr != oldptr) 847 *newptr++ = *oldptr; 848 else 849 newptr++; 850 851 } 852 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; 853 DEBUGP("NEW num_symtab %lu\n", nsyms); 854 symhdr->sh_size = nsyms * sizeof(Elf_Sym); 855 return module_bug_finalize(hdr, sechdrs, me); 856 } 857 858 void module_arch_cleanup(struct module *mod) 859 { 860 deregister_unwind_table(mod); 861 module_bug_cleanup(mod); 862 } 863