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 * Copyright (C) 2008 Helge Deller <deller@gmx.de> 10 * 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 * 27 * Notes: 28 * - PLT stub handling 29 * On 32bit (and sometimes 64bit) and with big kernel modules like xfs or 30 * ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may 31 * fail to reach their PLT stub if we only create one big stub array for 32 * all sections at the beginning of the core or init section. 33 * Instead we now insert individual PLT stub entries directly in front of 34 * of the code sections where the stubs are actually called. 35 * This reduces the distance between the PCREL location and the stub entry 36 * so that the relocations can be fulfilled. 37 * While calculating the final layout of the kernel module in memory, the 38 * kernel module loader calls arch_mod_section_prepend() to request the 39 * to be reserved amount of memory in front of each individual section. 40 * 41 * - SEGREL32 handling 42 * We are not doing SEGREL32 handling correctly. According to the ABI, we 43 * should do a value offset, like this: 44 * if (in_init(me, (void *)val)) 45 * val -= (uint32_t)me->module_init; 46 * else 47 * val -= (uint32_t)me->module_core; 48 * However, SEGREL32 is used only for PARISC unwind entries, and we want 49 * those entries to have an absolute address, and not just an offset. 50 * 51 * The unwind table mechanism has the ability to specify an offset for 52 * the unwind table; however, because we split off the init functions into 53 * a different piece of memory, it is not possible to do this using a 54 * single offset. Instead, we use the above hack for now. 55 */ 56 57 #include <linux/moduleloader.h> 58 #include <linux/elf.h> 59 #include <linux/vmalloc.h> 60 #include <linux/fs.h> 61 #include <linux/string.h> 62 #include <linux/kernel.h> 63 #include <linux/bug.h> 64 65 #include <asm/unwind.h> 66 67 #if 0 68 #define DEBUGP printk 69 #else 70 #define DEBUGP(fmt...) 71 #endif 72 73 #define RELOC_REACHABLE(val, bits) \ 74 (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \ 75 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \ 76 0 : 1) 77 78 #define CHECK_RELOC(val, bits) \ 79 if (!RELOC_REACHABLE(val, bits)) { \ 80 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \ 81 me->name, strtab + sym->st_name, (unsigned long)val, bits); \ 82 return -ENOEXEC; \ 83 } 84 85 /* Maximum number of GOT entries. We use a long displacement ldd from 86 * the bottom of the table, which has a maximum signed displacement of 87 * 0x3fff; however, since we're only going forward, this becomes 88 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have 89 * at most 1023 entries */ 90 #define MAX_GOTS 1023 91 92 /* three functions to determine where in the module core 93 * or init pieces the location is */ 94 static inline int in_init(struct module *me, void *loc) 95 { 96 return (loc >= me->module_init && 97 loc <= (me->module_init + me->init_size)); 98 } 99 100 static inline int in_core(struct module *me, void *loc) 101 { 102 return (loc >= me->module_core && 103 loc <= (me->module_core + me->core_size)); 104 } 105 106 static inline int in_local(struct module *me, void *loc) 107 { 108 return in_init(me, loc) || in_core(me, loc); 109 } 110 111 #ifndef CONFIG_64BIT 112 struct got_entry { 113 Elf32_Addr addr; 114 }; 115 116 struct stub_entry { 117 Elf32_Word insns[2]; /* each stub entry has two insns */ 118 }; 119 #else 120 struct got_entry { 121 Elf64_Addr addr; 122 }; 123 124 struct stub_entry { 125 Elf64_Word insns[4]; /* each stub entry has four insns */ 126 }; 127 #endif 128 129 /* Field selection types defined by hppa */ 130 #define rnd(x) (((x)+0x1000)&~0x1fff) 131 /* fsel: full 32 bits */ 132 #define fsel(v,a) ((v)+(a)) 133 /* lsel: select left 21 bits */ 134 #define lsel(v,a) (((v)+(a))>>11) 135 /* rsel: select right 11 bits */ 136 #define rsel(v,a) (((v)+(a))&0x7ff) 137 /* lrsel with rounding of addend to nearest 8k */ 138 #define lrsel(v,a) (((v)+rnd(a))>>11) 139 /* rrsel with rounding of addend to nearest 8k */ 140 #define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a))) 141 142 #define mask(x,sz) ((x) & ~((1<<(sz))-1)) 143 144 145 /* The reassemble_* functions prepare an immediate value for 146 insertion into an opcode. pa-risc uses all sorts of weird bitfields 147 in the instruction to hold the value. */ 148 static inline int reassemble_14(int as14) 149 { 150 return (((as14 & 0x1fff) << 1) | 151 ((as14 & 0x2000) >> 13)); 152 } 153 154 static inline int reassemble_17(int as17) 155 { 156 return (((as17 & 0x10000) >> 16) | 157 ((as17 & 0x0f800) << 5) | 158 ((as17 & 0x00400) >> 8) | 159 ((as17 & 0x003ff) << 3)); 160 } 161 162 static inline int reassemble_21(int as21) 163 { 164 return (((as21 & 0x100000) >> 20) | 165 ((as21 & 0x0ffe00) >> 8) | 166 ((as21 & 0x000180) << 7) | 167 ((as21 & 0x00007c) << 14) | 168 ((as21 & 0x000003) << 12)); 169 } 170 171 static inline int reassemble_22(int as22) 172 { 173 return (((as22 & 0x200000) >> 21) | 174 ((as22 & 0x1f0000) << 5) | 175 ((as22 & 0x00f800) << 5) | 176 ((as22 & 0x000400) >> 8) | 177 ((as22 & 0x0003ff) << 3)); 178 } 179 180 void *module_alloc(unsigned long size) 181 { 182 if (size == 0) 183 return NULL; 184 return vmalloc(size); 185 } 186 187 #ifndef CONFIG_64BIT 188 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 189 { 190 return 0; 191 } 192 193 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 194 { 195 return 0; 196 } 197 198 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 199 { 200 unsigned long cnt = 0; 201 202 for (; n > 0; n--, rela++) 203 { 204 switch (ELF32_R_TYPE(rela->r_info)) { 205 case R_PARISC_PCREL17F: 206 case R_PARISC_PCREL22F: 207 cnt++; 208 } 209 } 210 211 return cnt; 212 } 213 #else 214 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 215 { 216 unsigned long cnt = 0; 217 218 for (; n > 0; n--, rela++) 219 { 220 switch (ELF64_R_TYPE(rela->r_info)) { 221 case R_PARISC_LTOFF21L: 222 case R_PARISC_LTOFF14R: 223 case R_PARISC_PCREL22F: 224 cnt++; 225 } 226 } 227 228 return cnt; 229 } 230 231 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 232 { 233 unsigned long cnt = 0; 234 235 for (; n > 0; n--, rela++) 236 { 237 switch (ELF64_R_TYPE(rela->r_info)) { 238 case R_PARISC_FPTR64: 239 cnt++; 240 } 241 } 242 243 return cnt; 244 } 245 246 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 247 { 248 unsigned long cnt = 0; 249 250 for (; n > 0; n--, rela++) 251 { 252 switch (ELF64_R_TYPE(rela->r_info)) { 253 case R_PARISC_PCREL22F: 254 cnt++; 255 } 256 } 257 258 return cnt; 259 } 260 #endif 261 262 263 /* Free memory returned from module_alloc */ 264 void module_free(struct module *mod, void *module_region) 265 { 266 kfree(mod->arch.section); 267 mod->arch.section = NULL; 268 269 vfree(module_region); 270 /* FIXME: If module_region == mod->init_region, trim exception 271 table entries. */ 272 } 273 274 /* Additional bytes needed in front of individual sections */ 275 unsigned int arch_mod_section_prepend(struct module *mod, 276 unsigned int section) 277 { 278 /* size needed for all stubs of this section (including 279 * one additional for correct alignment of the stubs) */ 280 return (mod->arch.section[section].stub_entries + 1) 281 * sizeof(struct stub_entry); 282 } 283 284 #define CONST 285 int module_frob_arch_sections(CONST Elf_Ehdr *hdr, 286 CONST Elf_Shdr *sechdrs, 287 CONST char *secstrings, 288 struct module *me) 289 { 290 unsigned long gots = 0, fdescs = 0, len; 291 unsigned int i; 292 293 len = hdr->e_shnum * sizeof(me->arch.section[0]); 294 me->arch.section = kzalloc(len, GFP_KERNEL); 295 if (!me->arch.section) 296 return -ENOMEM; 297 298 for (i = 1; i < hdr->e_shnum; i++) { 299 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr; 300 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels); 301 unsigned int count, s; 302 303 if (strncmp(secstrings + sechdrs[i].sh_name, 304 ".PARISC.unwind", 14) == 0) 305 me->arch.unwind_section = i; 306 307 if (sechdrs[i].sh_type != SHT_RELA) 308 continue; 309 310 /* some of these are not relevant for 32-bit/64-bit 311 * we leave them here to make the code common. the 312 * compiler will do its thing and optimize out the 313 * stuff we don't need 314 */ 315 gots += count_gots(rels, nrels); 316 fdescs += count_fdescs(rels, nrels); 317 318 /* XXX: By sorting the relocs and finding duplicate entries 319 * we could reduce the number of necessary stubs and save 320 * some memory. */ 321 count = count_stubs(rels, nrels); 322 if (!count) 323 continue; 324 325 /* so we need relocation stubs. reserve necessary memory. */ 326 /* sh_info gives the section for which we need to add stubs. */ 327 s = sechdrs[i].sh_info; 328 329 /* each code section should only have one relocation section */ 330 WARN_ON(me->arch.section[s].stub_entries); 331 332 /* store number of stubs we need for this section */ 333 me->arch.section[s].stub_entries += count; 334 } 335 336 /* align things a bit */ 337 me->core_size = ALIGN(me->core_size, 16); 338 me->arch.got_offset = me->core_size; 339 me->core_size += gots * sizeof(struct got_entry); 340 341 me->core_size = ALIGN(me->core_size, 16); 342 me->arch.fdesc_offset = me->core_size; 343 me->core_size += fdescs * sizeof(Elf_Fdesc); 344 345 me->arch.got_max = gots; 346 me->arch.fdesc_max = fdescs; 347 348 return 0; 349 } 350 351 #ifdef CONFIG_64BIT 352 static Elf64_Word get_got(struct module *me, unsigned long value, long addend) 353 { 354 unsigned int i; 355 struct got_entry *got; 356 357 value += addend; 358 359 BUG_ON(value == 0); 360 361 got = me->module_core + me->arch.got_offset; 362 for (i = 0; got[i].addr; i++) 363 if (got[i].addr == value) 364 goto out; 365 366 BUG_ON(++me->arch.got_count > me->arch.got_max); 367 368 got[i].addr = value; 369 out: 370 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry), 371 value); 372 return i * sizeof(struct got_entry); 373 } 374 #endif /* CONFIG_64BIT */ 375 376 #ifdef CONFIG_64BIT 377 static Elf_Addr get_fdesc(struct module *me, unsigned long value) 378 { 379 Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset; 380 381 if (!value) { 382 printk(KERN_ERR "%s: zero OPD requested!\n", me->name); 383 return 0; 384 } 385 386 /* Look for existing fdesc entry. */ 387 while (fdesc->addr) { 388 if (fdesc->addr == value) 389 return (Elf_Addr)fdesc; 390 fdesc++; 391 } 392 393 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max); 394 395 /* Create new one */ 396 fdesc->addr = value; 397 fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset; 398 return (Elf_Addr)fdesc; 399 } 400 #endif /* CONFIG_64BIT */ 401 402 enum elf_stub_type { 403 ELF_STUB_GOT, 404 ELF_STUB_MILLI, 405 ELF_STUB_DIRECT, 406 }; 407 408 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend, 409 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec) 410 { 411 struct stub_entry *stub; 412 413 /* initialize stub_offset to point in front of the section */ 414 if (!me->arch.section[targetsec].stub_offset) { 415 loc0 -= (me->arch.section[targetsec].stub_entries + 1) * 416 sizeof(struct stub_entry); 417 /* get correct alignment for the stubs */ 418 loc0 = ALIGN(loc0, sizeof(struct stub_entry)); 419 me->arch.section[targetsec].stub_offset = loc0; 420 } 421 422 /* get address of stub entry */ 423 stub = (void *) me->arch.section[targetsec].stub_offset; 424 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry); 425 426 /* do not write outside available stub area */ 427 BUG_ON(0 == me->arch.section[targetsec].stub_entries--); 428 429 430 #ifndef CONFIG_64BIT 431 /* for 32-bit the stub looks like this: 432 * ldil L'XXX,%r1 433 * be,n R'XXX(%sr4,%r1) 434 */ 435 //value = *(unsigned long *)((value + addend) & ~3); /* why? */ 436 437 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */ 438 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */ 439 440 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 441 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4); 442 443 #else 444 /* for 64-bit we have three kinds of stubs: 445 * for normal function calls: 446 * ldd 0(%dp),%dp 447 * ldd 10(%dp), %r1 448 * bve (%r1) 449 * ldd 18(%dp), %dp 450 * 451 * for millicode: 452 * ldil 0, %r1 453 * ldo 0(%r1), %r1 454 * ldd 10(%r1), %r1 455 * bve,n (%r1) 456 * 457 * for direct branches (jumps between different section of the 458 * same module): 459 * ldil 0, %r1 460 * ldo 0(%r1), %r1 461 * bve,n (%r1) 462 */ 463 switch (stub_type) { 464 case ELF_STUB_GOT: 465 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */ 466 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */ 467 stub->insns[2] = 0xe820d000; /* bve (%r1) */ 468 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */ 469 470 stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff); 471 break; 472 case ELF_STUB_MILLI: 473 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 474 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 475 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */ 476 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */ 477 478 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 479 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 480 break; 481 case ELF_STUB_DIRECT: 482 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 483 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 484 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */ 485 486 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 487 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 488 break; 489 } 490 491 #endif 492 493 return (Elf_Addr)stub; 494 } 495 496 int apply_relocate(Elf_Shdr *sechdrs, 497 const char *strtab, 498 unsigned int symindex, 499 unsigned int relsec, 500 struct module *me) 501 { 502 /* parisc should not need this ... */ 503 printk(KERN_ERR "module %s: RELOCATION unsupported\n", 504 me->name); 505 return -ENOEXEC; 506 } 507 508 #ifndef CONFIG_64BIT 509 int apply_relocate_add(Elf_Shdr *sechdrs, 510 const char *strtab, 511 unsigned int symindex, 512 unsigned int relsec, 513 struct module *me) 514 { 515 int i; 516 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 517 Elf32_Sym *sym; 518 Elf32_Word *loc; 519 Elf32_Addr val; 520 Elf32_Sword addend; 521 Elf32_Addr dot; 522 Elf_Addr loc0; 523 unsigned int targetsec = sechdrs[relsec].sh_info; 524 //unsigned long dp = (unsigned long)$global$; 525 register unsigned long dp asm ("r27"); 526 527 DEBUGP("Applying relocate section %u to %u\n", relsec, 528 targetsec); 529 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 530 /* This is where to make the change */ 531 loc = (void *)sechdrs[targetsec].sh_addr 532 + rel[i].r_offset; 533 /* This is the start of the target section */ 534 loc0 = sechdrs[targetsec].sh_addr; 535 /* This is the symbol it is referring to */ 536 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 537 + ELF32_R_SYM(rel[i].r_info); 538 if (!sym->st_value) { 539 printk(KERN_WARNING "%s: Unknown symbol %s\n", 540 me->name, strtab + sym->st_name); 541 return -ENOENT; 542 } 543 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 544 dot = (Elf32_Addr)loc & ~0x03; 545 546 val = sym->st_value; 547 addend = rel[i].r_addend; 548 549 #if 0 550 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t : 551 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n", 552 strtab + sym->st_name, 553 (uint32_t)loc, val, addend, 554 r(R_PARISC_PLABEL32) 555 r(R_PARISC_DIR32) 556 r(R_PARISC_DIR21L) 557 r(R_PARISC_DIR14R) 558 r(R_PARISC_SEGREL32) 559 r(R_PARISC_DPREL21L) 560 r(R_PARISC_DPREL14R) 561 r(R_PARISC_PCREL17F) 562 r(R_PARISC_PCREL22F) 563 "UNKNOWN"); 564 #undef r 565 #endif 566 567 switch (ELF32_R_TYPE(rel[i].r_info)) { 568 case R_PARISC_PLABEL32: 569 /* 32-bit function address */ 570 /* no function descriptors... */ 571 *loc = fsel(val, addend); 572 break; 573 case R_PARISC_DIR32: 574 /* direct 32-bit ref */ 575 *loc = fsel(val, addend); 576 break; 577 case R_PARISC_DIR21L: 578 /* left 21 bits of effective address */ 579 val = lrsel(val, addend); 580 *loc = mask(*loc, 21) | reassemble_21(val); 581 break; 582 case R_PARISC_DIR14R: 583 /* right 14 bits of effective address */ 584 val = rrsel(val, addend); 585 *loc = mask(*loc, 14) | reassemble_14(val); 586 break; 587 case R_PARISC_SEGREL32: 588 /* 32-bit segment relative address */ 589 /* See note about special handling of SEGREL32 at 590 * the beginning of this file. 591 */ 592 *loc = fsel(val, addend); 593 break; 594 case R_PARISC_DPREL21L: 595 /* left 21 bit of relative address */ 596 val = lrsel(val - dp, addend); 597 *loc = mask(*loc, 21) | reassemble_21(val); 598 break; 599 case R_PARISC_DPREL14R: 600 /* right 14 bit of relative address */ 601 val = rrsel(val - dp, addend); 602 *loc = mask(*loc, 14) | reassemble_14(val); 603 break; 604 case R_PARISC_PCREL17F: 605 /* 17-bit PC relative address */ 606 /* calculate direct call offset */ 607 val += addend; 608 val = (val - dot - 8)/4; 609 if (!RELOC_REACHABLE(val, 17)) { 610 /* direct distance too far, create 611 * stub entry instead */ 612 val = get_stub(me, sym->st_value, addend, 613 ELF_STUB_DIRECT, loc0, targetsec); 614 val = (val - dot - 8)/4; 615 CHECK_RELOC(val, 17); 616 } 617 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val); 618 break; 619 case R_PARISC_PCREL22F: 620 /* 22-bit PC relative address; only defined for pa20 */ 621 /* calculate direct call offset */ 622 val += addend; 623 val = (val - dot - 8)/4; 624 if (!RELOC_REACHABLE(val, 22)) { 625 /* direct distance too far, create 626 * stub entry instead */ 627 val = get_stub(me, sym->st_value, addend, 628 ELF_STUB_DIRECT, loc0, targetsec); 629 val = (val - dot - 8)/4; 630 CHECK_RELOC(val, 22); 631 } 632 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 633 break; 634 635 default: 636 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 637 me->name, ELF32_R_TYPE(rel[i].r_info)); 638 return -ENOEXEC; 639 } 640 } 641 642 return 0; 643 } 644 645 #else 646 int apply_relocate_add(Elf_Shdr *sechdrs, 647 const char *strtab, 648 unsigned int symindex, 649 unsigned int relsec, 650 struct module *me) 651 { 652 int i; 653 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; 654 Elf64_Sym *sym; 655 Elf64_Word *loc; 656 Elf64_Xword *loc64; 657 Elf64_Addr val; 658 Elf64_Sxword addend; 659 Elf64_Addr dot; 660 Elf_Addr loc0; 661 unsigned int targetsec = sechdrs[relsec].sh_info; 662 663 DEBUGP("Applying relocate section %u to %u\n", relsec, 664 targetsec); 665 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 666 /* This is where to make the change */ 667 loc = (void *)sechdrs[targetsec].sh_addr 668 + rel[i].r_offset; 669 /* This is the start of the target section */ 670 loc0 = sechdrs[targetsec].sh_addr; 671 /* This is the symbol it is referring to */ 672 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr 673 + ELF64_R_SYM(rel[i].r_info); 674 if (!sym->st_value) { 675 printk(KERN_WARNING "%s: Unknown symbol %s\n", 676 me->name, strtab + sym->st_name); 677 return -ENOENT; 678 } 679 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 680 dot = (Elf64_Addr)loc & ~0x03; 681 loc64 = (Elf64_Xword *)loc; 682 683 val = sym->st_value; 684 addend = rel[i].r_addend; 685 686 #if 0 687 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t : 688 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n", 689 strtab + sym->st_name, 690 loc, val, addend, 691 r(R_PARISC_LTOFF14R) 692 r(R_PARISC_LTOFF21L) 693 r(R_PARISC_PCREL22F) 694 r(R_PARISC_DIR64) 695 r(R_PARISC_SEGREL32) 696 r(R_PARISC_FPTR64) 697 "UNKNOWN"); 698 #undef r 699 #endif 700 701 switch (ELF64_R_TYPE(rel[i].r_info)) { 702 case R_PARISC_LTOFF21L: 703 /* LT-relative; left 21 bits */ 704 val = get_got(me, val, addend); 705 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n", 706 strtab + sym->st_name, 707 loc, val); 708 val = lrsel(val, 0); 709 *loc = mask(*loc, 21) | reassemble_21(val); 710 break; 711 case R_PARISC_LTOFF14R: 712 /* L(ltoff(val+addend)) */ 713 /* LT-relative; right 14 bits */ 714 val = get_got(me, val, addend); 715 val = rrsel(val, 0); 716 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n", 717 strtab + sym->st_name, 718 loc, val); 719 *loc = mask(*loc, 14) | reassemble_14(val); 720 break; 721 case R_PARISC_PCREL22F: 722 /* PC-relative; 22 bits */ 723 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n", 724 strtab + sym->st_name, 725 loc, val); 726 val += addend; 727 /* can we reach it locally? */ 728 if (in_local(me, (void *)val)) { 729 /* this is the case where the symbol is local 730 * to the module, but in a different section, 731 * so stub the jump in case it's more than 22 732 * bits away */ 733 val = (val - dot - 8)/4; 734 if (!RELOC_REACHABLE(val, 22)) { 735 /* direct distance too far, create 736 * stub entry instead */ 737 val = get_stub(me, sym->st_value, 738 addend, ELF_STUB_DIRECT, 739 loc0, targetsec); 740 } else { 741 /* Ok, we can reach it directly. */ 742 val = sym->st_value; 743 val += addend; 744 } 745 } else { 746 val = sym->st_value; 747 if (strncmp(strtab + sym->st_name, "$$", 2) 748 == 0) 749 val = get_stub(me, val, addend, ELF_STUB_MILLI, 750 loc0, targetsec); 751 else 752 val = get_stub(me, val, addend, ELF_STUB_GOT, 753 loc0, targetsec); 754 } 755 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 756 strtab + sym->st_name, loc, sym->st_value, 757 addend, val); 758 val = (val - dot - 8)/4; 759 CHECK_RELOC(val, 22); 760 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 761 break; 762 case R_PARISC_DIR64: 763 /* 64-bit effective address */ 764 *loc64 = val + addend; 765 break; 766 case R_PARISC_SEGREL32: 767 /* 32-bit segment relative address */ 768 /* See note about special handling of SEGREL32 at 769 * the beginning of this file. 770 */ 771 *loc = fsel(val, addend); 772 break; 773 case R_PARISC_FPTR64: 774 /* 64-bit function address */ 775 if(in_local(me, (void *)(val + addend))) { 776 *loc64 = get_fdesc(me, val+addend); 777 DEBUGP("FDESC for %s at %p points to %lx\n", 778 strtab + sym->st_name, *loc64, 779 ((Elf_Fdesc *)*loc64)->addr); 780 } else { 781 /* if the symbol is not local to this 782 * module then val+addend is a pointer 783 * to the function descriptor */ 784 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n", 785 strtab + sym->st_name, 786 loc, val); 787 *loc64 = val + addend; 788 } 789 break; 790 791 default: 792 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n", 793 me->name, ELF64_R_TYPE(rel[i].r_info)); 794 return -ENOEXEC; 795 } 796 } 797 return 0; 798 } 799 #endif 800 801 static void 802 register_unwind_table(struct module *me, 803 const Elf_Shdr *sechdrs) 804 { 805 unsigned char *table, *end; 806 unsigned long gp; 807 808 if (!me->arch.unwind_section) 809 return; 810 811 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr; 812 end = table + sechdrs[me->arch.unwind_section].sh_size; 813 gp = (Elf_Addr)me->module_core + me->arch.got_offset; 814 815 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n", 816 me->arch.unwind_section, table, end, gp); 817 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end); 818 } 819 820 static void 821 deregister_unwind_table(struct module *me) 822 { 823 if (me->arch.unwind) 824 unwind_table_remove(me->arch.unwind); 825 } 826 827 int module_finalize(const Elf_Ehdr *hdr, 828 const Elf_Shdr *sechdrs, 829 struct module *me) 830 { 831 int i; 832 unsigned long nsyms; 833 const char *strtab = NULL; 834 Elf_Sym *newptr, *oldptr; 835 Elf_Shdr *symhdr = NULL; 836 #ifdef DEBUG 837 Elf_Fdesc *entry; 838 u32 *addr; 839 840 entry = (Elf_Fdesc *)me->init; 841 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry, 842 entry->gp, entry->addr); 843 addr = (u32 *)entry->addr; 844 printk("INSNS: %x %x %x %x\n", 845 addr[0], addr[1], addr[2], addr[3]); 846 printk("got entries used %ld, gots max %ld\n" 847 "fdescs used %ld, fdescs max %ld\n", 848 me->arch.got_count, me->arch.got_max, 849 me->arch.fdesc_count, me->arch.fdesc_max); 850 #endif 851 852 register_unwind_table(me, sechdrs); 853 854 /* haven't filled in me->symtab yet, so have to find it 855 * ourselves */ 856 for (i = 1; i < hdr->e_shnum; i++) { 857 if(sechdrs[i].sh_type == SHT_SYMTAB 858 && (sechdrs[i].sh_type & SHF_ALLOC)) { 859 int strindex = sechdrs[i].sh_link; 860 /* FIXME: AWFUL HACK 861 * The cast is to drop the const from 862 * the sechdrs pointer */ 863 symhdr = (Elf_Shdr *)&sechdrs[i]; 864 strtab = (char *)sechdrs[strindex].sh_addr; 865 break; 866 } 867 } 868 869 DEBUGP("module %s: strtab %p, symhdr %p\n", 870 me->name, strtab, symhdr); 871 872 if(me->arch.got_count > MAX_GOTS) { 873 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n", 874 me->name, me->arch.got_count, MAX_GOTS); 875 return -EINVAL; 876 } 877 878 kfree(me->arch.section); 879 me->arch.section = NULL; 880 881 /* no symbol table */ 882 if(symhdr == NULL) 883 return 0; 884 885 oldptr = (void *)symhdr->sh_addr; 886 newptr = oldptr + 1; /* we start counting at 1 */ 887 nsyms = symhdr->sh_size / sizeof(Elf_Sym); 888 DEBUGP("OLD num_symtab %lu\n", nsyms); 889 890 for (i = 1; i < nsyms; i++) { 891 oldptr++; /* note, count starts at 1 so preincrement */ 892 if(strncmp(strtab + oldptr->st_name, 893 ".L", 2) == 0) 894 continue; 895 896 if(newptr != oldptr) 897 *newptr++ = *oldptr; 898 else 899 newptr++; 900 901 } 902 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; 903 DEBUGP("NEW num_symtab %lu\n", nsyms); 904 symhdr->sh_size = nsyms * sizeof(Elf_Sym); 905 return module_bug_finalize(hdr, sechdrs, me); 906 } 907 908 void module_arch_cleanup(struct module *mod) 909 { 910 deregister_unwind_table(mod); 911 module_bug_cleanup(mod); 912 } 913