1 /* $NetBSD: ppc_reloc.c,v 1.10 2001/09/10 06:09:41 mycroft Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD 5 * 6 * Copyright (C) 1998 Tsubai Masanari 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. The name of the author may not be used to endorse or promote products 18 * derived from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 * 31 * $FreeBSD$ 32 */ 33 34 #include <sys/param.h> 35 #include <sys/mman.h> 36 37 #include <errno.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 #include <machine/cpu.h> 43 #include <machine/atomic.h> 44 #include <machine/md_var.h> 45 46 #include "debug.h" 47 #include "rtld.h" 48 49 #define _ppc_ha(x) ((((u_int32_t)(x) & 0x8000) ? \ 50 ((u_int32_t)(x) + 0x10000) : (u_int32_t)(x)) >> 16) 51 #define _ppc_la(x) ((u_int32_t)(x) & 0xffff) 52 53 #define min(a,b) (((a) < (b)) ? (a) : (b)) 54 #define max(a,b) (((a) > (b)) ? (a) : (b)) 55 56 #define PLT_EXTENDED_BEGIN (1 << 13) 57 #define JMPTAB_BASE(N) (18 + N*2 + ((N > PLT_EXTENDED_BEGIN) ? \ 58 (N - PLT_EXTENDED_BEGIN)*2 : 0)) 59 60 void _rtld_bind_secureplt_start(void); 61 62 /* 63 * Process the R_PPC_COPY relocations 64 */ 65 int 66 do_copy_relocations(Obj_Entry *dstobj) 67 { 68 const Elf_Rela *relalim; 69 const Elf_Rela *rela; 70 71 /* 72 * COPY relocs are invalid outside of the main program 73 */ 74 assert(dstobj->mainprog); 75 76 relalim = (const Elf_Rela *)((const char *) dstobj->rela + 77 dstobj->relasize); 78 for (rela = dstobj->rela; rela < relalim; rela++) { 79 void *dstaddr; 80 const Elf_Sym *dstsym; 81 const char *name; 82 size_t size; 83 const void *srcaddr; 84 const Elf_Sym *srcsym = NULL; 85 const Obj_Entry *srcobj, *defobj; 86 SymLook req; 87 int res; 88 89 if (ELF_R_TYPE(rela->r_info) != R_PPC_COPY) { 90 continue; 91 } 92 93 dstaddr = (void *)(dstobj->relocbase + rela->r_offset); 94 dstsym = dstobj->symtab + ELF_R_SYM(rela->r_info); 95 name = dstobj->strtab + dstsym->st_name; 96 size = dstsym->st_size; 97 symlook_init(&req, name); 98 req.ventry = fetch_ventry(dstobj, ELF_R_SYM(rela->r_info)); 99 req.flags = SYMLOOK_EARLY; 100 101 for (srcobj = globallist_next(dstobj); srcobj != NULL; 102 srcobj = globallist_next(srcobj)) { 103 res = symlook_obj(&req, srcobj); 104 if (res == 0) { 105 srcsym = req.sym_out; 106 defobj = req.defobj_out; 107 break; 108 } 109 } 110 111 if (srcobj == NULL) { 112 _rtld_error("Undefined symbol \"%s\" " 113 " referenced from COPY" 114 " relocation in %s", name, dstobj->path); 115 return (-1); 116 } 117 118 srcaddr = (const void *)(defobj->relocbase+srcsym->st_value); 119 memcpy(dstaddr, srcaddr, size); 120 dbg("copy_reloc: src=%p,dst=%p,size=%d\n",srcaddr,dstaddr,size); 121 } 122 123 return (0); 124 } 125 126 127 /* 128 * Perform early relocation of the run-time linker image 129 */ 130 void 131 reloc_non_plt_self(Elf_Dyn *dynp, Elf_Addr relocbase) 132 { 133 const Elf_Rela *rela = NULL, *relalim; 134 Elf_Addr relasz = 0; 135 Elf_Addr *where; 136 137 /* 138 * Extract the rela/relasz values from the dynamic section 139 */ 140 for (; dynp->d_tag != DT_NULL; dynp++) { 141 switch (dynp->d_tag) { 142 case DT_RELA: 143 rela = (const Elf_Rela *)(relocbase+dynp->d_un.d_ptr); 144 break; 145 case DT_RELASZ: 146 relasz = dynp->d_un.d_val; 147 break; 148 } 149 } 150 151 /* 152 * Relocate these values 153 */ 154 relalim = (const Elf_Rela *)((const char *)rela + relasz); 155 for (; rela < relalim; rela++) { 156 where = (Elf_Addr *)(relocbase + rela->r_offset); 157 *where = (Elf_Addr)(relocbase + rela->r_addend); 158 } 159 } 160 161 162 /* 163 * Relocate a non-PLT object with addend. 164 */ 165 static int 166 reloc_nonplt_object(Obj_Entry *obj_rtld __unused, Obj_Entry *obj, 167 const Elf_Rela *rela, SymCache *cache, int flags, RtldLockState *lockstate) 168 { 169 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 170 const Elf_Sym *def; 171 const Obj_Entry *defobj; 172 Elf_Addr tmp; 173 174 switch (ELF_R_TYPE(rela->r_info)) { 175 176 case R_PPC_NONE: 177 break; 178 179 case R_PPC_ADDR32: /* word32 S + A */ 180 case R_PPC_GLOB_DAT: /* word32 S + A */ 181 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, 182 flags, cache, lockstate); 183 if (def == NULL) { 184 return (-1); 185 } 186 187 tmp = (Elf_Addr)(defobj->relocbase + def->st_value + 188 rela->r_addend); 189 190 /* Don't issue write if unnecessary; avoid COW page fault */ 191 if (*where != tmp) { 192 *where = tmp; 193 } 194 break; 195 196 case R_PPC_RELATIVE: /* word32 B + A */ 197 tmp = (Elf_Addr)(obj->relocbase + rela->r_addend); 198 199 /* As above, don't issue write unnecessarily */ 200 if (*where != tmp) { 201 *where = tmp; 202 } 203 break; 204 205 case R_PPC_COPY: 206 /* 207 * These are deferred until all other relocations 208 * have been done. All we do here is make sure 209 * that the COPY relocation is not in a shared 210 * library. They are allowed only in executable 211 * files. 212 */ 213 if (!obj->mainprog) { 214 _rtld_error("%s: Unexpected R_COPY " 215 " relocation in shared library", 216 obj->path); 217 return (-1); 218 } 219 break; 220 221 case R_PPC_JMP_SLOT: 222 /* 223 * These will be handled by the plt/jmpslot routines 224 */ 225 break; 226 227 case R_PPC_DTPMOD32: 228 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, 229 flags, cache, lockstate); 230 231 if (def == NULL) 232 return (-1); 233 234 *where = (Elf_Addr) defobj->tlsindex; 235 236 break; 237 238 case R_PPC_TPREL32: 239 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, 240 flags, cache, lockstate); 241 242 if (def == NULL) 243 return (-1); 244 245 /* 246 * We lazily allocate offsets for static TLS as we 247 * see the first relocation that references the 248 * TLS block. This allows us to support (small 249 * amounts of) static TLS in dynamically loaded 250 * modules. If we run out of space, we generate an 251 * error. 252 */ 253 if (!defobj->tls_done) { 254 if (!allocate_tls_offset( 255 __DECONST(Obj_Entry *, defobj))) { 256 _rtld_error("%s: No space available for static " 257 "Thread Local Storage", obj->path); 258 return (-1); 259 } 260 } 261 262 *(Elf_Addr **)where = *where * sizeof(Elf_Addr) 263 + (Elf_Addr *)(def->st_value + rela->r_addend 264 + defobj->tlsoffset - TLS_TP_OFFSET - TLS_TCB_SIZE); 265 266 break; 267 268 case R_PPC_DTPREL32: 269 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, 270 flags, cache, lockstate); 271 272 if (def == NULL) 273 return (-1); 274 275 *where += (Elf_Addr)(def->st_value + rela->r_addend 276 - TLS_DTV_OFFSET); 277 278 break; 279 280 default: 281 _rtld_error("%s: Unsupported relocation type %d" 282 " in non-PLT relocations\n", obj->path, 283 ELF_R_TYPE(rela->r_info)); 284 return (-1); 285 } 286 return (0); 287 } 288 289 290 /* 291 * Process non-PLT relocations 292 */ 293 int 294 reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags, 295 RtldLockState *lockstate) 296 { 297 const Elf_Rela *relalim; 298 const Elf_Rela *rela; 299 const Elf_Phdr *phdr; 300 SymCache *cache; 301 int r = -1; 302 303 if ((flags & SYMLOOK_IFUNC) != 0) 304 /* XXX not implemented */ 305 return (0); 306 307 /* 308 * The dynamic loader may be called from a thread, we have 309 * limited amounts of stack available so we cannot use alloca(). 310 */ 311 if (obj != obj_rtld) { 312 cache = calloc(obj->dynsymcount, sizeof(SymCache)); 313 /* No need to check for NULL here */ 314 } else 315 cache = NULL; 316 317 /* 318 * From the SVR4 PPC ABI: 319 * "The PowerPC family uses only the Elf32_Rela relocation 320 * entries with explicit addends." 321 */ 322 relalim = (const Elf_Rela *)((const char *)obj->rela + obj->relasize); 323 for (rela = obj->rela; rela < relalim; rela++) { 324 if (reloc_nonplt_object(obj_rtld, obj, rela, cache, flags, 325 lockstate) < 0) 326 goto done; 327 } 328 r = 0; 329 done: 330 if (cache != NULL) 331 free(cache); 332 333 /* 334 * Synchronize icache for executable segments in case we made 335 * any changes. 336 */ 337 for (phdr = obj->phdr; 338 (const char *)phdr < (const char *)obj->phdr + obj->phsize; 339 phdr++) { 340 if (phdr->p_type == PT_LOAD && (phdr->p_flags & PF_X) != 0) { 341 __syncicache(obj->relocbase + phdr->p_vaddr, 342 phdr->p_memsz); 343 } 344 } 345 346 return (r); 347 } 348 349 /* 350 * Initialise a PLT slot to the resolving trampoline 351 */ 352 static int 353 reloc_plt_object(Obj_Entry *obj, const Elf_Rela *rela) 354 { 355 Elf_Word *where = (Elf_Word *)(obj->relocbase + rela->r_offset); 356 Elf_Addr *pltresolve, *pltlongresolve, *jmptab; 357 Elf_Addr distance; 358 int N = obj->pltrelasize / sizeof(Elf_Rela); 359 int reloff; 360 361 reloff = rela - obj->pltrela; 362 363 if (reloff < 0) 364 return (-1); 365 366 if (obj->gotptr != NULL) { 367 *where += (Elf_Addr)obj->relocbase; 368 return (0); 369 } 370 371 pltlongresolve = obj->pltgot + 5; 372 pltresolve = pltlongresolve + 5; 373 374 distance = (Elf_Addr)pltresolve - (Elf_Addr)(where + 1); 375 376 dbg(" reloc_plt_object: where=%p,pltres=%p,reloff=%x,distance=%x", 377 (void *)where, (void *)pltresolve, reloff, distance); 378 379 if (reloff < PLT_EXTENDED_BEGIN) { 380 /* li r11,reloff */ 381 /* b pltresolve */ 382 where[0] = 0x39600000 | reloff; 383 where[1] = 0x48000000 | (distance & 0x03fffffc); 384 } else { 385 jmptab = obj->pltgot + JMPTAB_BASE(N); 386 jmptab[reloff] = (u_int)pltlongresolve; 387 388 /* lis r11,jmptab[reloff]@ha */ 389 /* lwzu r12,jmptab[reloff]@l(r11) */ 390 /* mtctr r12 */ 391 /* bctr */ 392 where[0] = 0x3d600000 | _ppc_ha(&jmptab[reloff]); 393 where[1] = 0x858b0000 | _ppc_la(&jmptab[reloff]); 394 where[2] = 0x7d8903a6; 395 where[3] = 0x4e800420; 396 } 397 398 399 /* 400 * The icache will be sync'd in reloc_plt, which is called 401 * after all the slots have been updated 402 */ 403 404 return (0); 405 } 406 407 408 /* 409 * Process the PLT relocations. 410 */ 411 int 412 reloc_plt(Obj_Entry *obj, int flags __unused, RtldLockState *lockstate __unused) 413 { 414 const Elf_Rela *relalim; 415 const Elf_Rela *rela; 416 int N = obj->pltrelasize / sizeof(Elf_Rela); 417 418 if (obj->pltrelasize != 0) { 419 420 relalim = (const Elf_Rela *)((const char *)obj->pltrela + 421 obj->pltrelasize); 422 for (rela = obj->pltrela; rela < relalim; rela++) { 423 assert(ELF_R_TYPE(rela->r_info) == R_PPC_JMP_SLOT); 424 425 if (reloc_plt_object(obj, rela) < 0) { 426 return (-1); 427 } 428 } 429 } 430 431 /* 432 * Sync the icache for the byte range represented by the 433 * trampoline routines and call slots. 434 */ 435 if (obj->pltgot != NULL && obj->gotptr == NULL) 436 __syncicache(obj->pltgot, JMPTAB_BASE(N)*4); 437 438 return (0); 439 } 440 441 442 /* 443 * LD_BIND_NOW was set - force relocation for all jump slots 444 */ 445 int 446 reloc_jmpslots(Obj_Entry *obj, int flags, RtldLockState *lockstate) 447 { 448 const Obj_Entry *defobj; 449 const Elf_Rela *relalim; 450 const Elf_Rela *rela; 451 const Elf_Sym *def; 452 Elf_Addr *where; 453 Elf_Addr target; 454 455 relalim = (const Elf_Rela *)((const char *)obj->pltrela + 456 obj->pltrelasize); 457 for (rela = obj->pltrela; rela < relalim; rela++) { 458 assert(ELF_R_TYPE(rela->r_info) == R_PPC_JMP_SLOT); 459 where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 460 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, 461 SYMLOOK_IN_PLT | flags, NULL, lockstate); 462 if (def == NULL) { 463 dbg("reloc_jmpslots: sym not found"); 464 return (-1); 465 } 466 467 target = (Elf_Addr)(defobj->relocbase + def->st_value); 468 469 #if 0 470 /* PG XXX */ 471 dbg("\"%s\" in \"%s\" --> %p in \"%s\"", 472 defobj->strtab + def->st_name, basename(obj->path), 473 (void *)target, basename(defobj->path)); 474 #endif 475 476 reloc_jmpslot(where, target, defobj, obj, 477 (const Elf_Rel *) rela); 478 } 479 480 obj->jmpslots_done = true; 481 482 return (0); 483 } 484 485 486 /* 487 * Update the value of a PLT jump slot. Branch directly to the target if 488 * it is within +/- 32Mb, otherwise go indirectly via the pltcall 489 * trampoline call and jump table. 490 */ 491 Elf_Addr 492 reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target, 493 const Obj_Entry *defobj __unused, const Obj_Entry *obj, const Elf_Rel *rel) 494 { 495 Elf_Addr offset; 496 const Elf_Rela *rela = (const Elf_Rela *) rel; 497 498 dbg(" reloc_jmpslot: where=%p, target=%p", 499 (void *)wherep, (void *)target); 500 501 if (ld_bind_not) 502 goto out; 503 504 /* 505 * At the PLT entry pointed at by `wherep', construct 506 * a direct transfer to the now fully resolved function 507 * address. 508 */ 509 offset = target - (Elf_Addr)wherep; 510 511 if (obj->gotptr != NULL) { 512 assert(wherep >= (Elf_Word *)obj->pltgot); 513 assert(wherep < 514 (Elf_Word *)obj->pltgot + obj->pltrelasize); 515 *wherep = target; 516 goto out; 517 } 518 519 if (abs((int)offset) < 32*1024*1024) { /* inside 32MB? */ 520 /* b value # branch directly */ 521 *wherep = 0x48000000 | (offset & 0x03fffffc); 522 __syncicache(wherep, 4); 523 } else { 524 Elf_Addr *pltcall, *jmptab; 525 int distance; 526 int N = obj->pltrelasize / sizeof(Elf_Rela); 527 int reloff = rela - obj->pltrela; 528 529 if (reloff < 0) 530 return (-1); 531 532 pltcall = obj->pltgot; 533 534 dbg(" reloc_jmpslot: indir, reloff=%x, N=%x\n", 535 reloff, N); 536 537 jmptab = obj->pltgot + JMPTAB_BASE(N); 538 jmptab[reloff] = target; 539 mb(); /* Order jmptab update before next changes */ 540 541 if (reloff < PLT_EXTENDED_BEGIN) { 542 /* for extended PLT entries, we keep the old code */ 543 544 distance = (Elf_Addr)pltcall - (Elf_Addr)(wherep + 1); 545 546 /* li r11,reloff */ 547 /* b pltcall # use indirect pltcall routine */ 548 549 /* first instruction same as before */ 550 wherep[1] = 0x48000000 | (distance & 0x03fffffc); 551 __syncicache(wherep, 8); 552 } 553 } 554 555 out: 556 return (target); 557 } 558 559 int 560 reloc_iresolve(Obj_Entry *obj __unused, 561 struct Struct_RtldLockState *lockstate __unused) 562 { 563 564 /* XXX not implemented */ 565 return (0); 566 } 567 568 int 569 reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, 570 struct Struct_RtldLockState *lockstate __unused) 571 { 572 573 /* XXX not implemented */ 574 return (0); 575 } 576 577 /* 578 * Setup the plt glue routines. 579 */ 580 #define PLTCALL_SIZE 20 581 #define PLTLONGRESOLVE_SIZE 20 582 #define PLTRESOLVE_SIZE 24 583 584 void 585 init_pltgot(Obj_Entry *obj) 586 { 587 Elf_Word *pltcall, *pltresolve, *pltlongresolve; 588 Elf_Word *jmptab; 589 int N = obj->pltrelasize / sizeof(Elf_Rela); 590 591 pltcall = obj->pltgot; 592 593 if (pltcall == NULL) { 594 return; 595 } 596 597 /* Handle Secure-PLT first, if applicable. */ 598 if (obj->gotptr != NULL) { 599 obj->gotptr[1] = (Elf_Addr)_rtld_bind_secureplt_start; 600 obj->gotptr[2] = (Elf_Addr)obj; 601 dbg("obj %s secure-plt gotptr=%p start=%p obj=%p", 602 obj->path, obj->gotptr, 603 (void *)obj->gotptr[1], (void *)obj->gotptr[2]); 604 return; 605 } 606 607 /* 608 * From the SVR4 PPC ABI: 609 * 610 * 'The first 18 words (72 bytes) of the PLT are reserved for 611 * use by the dynamic linker. 612 * ... 613 * 'If the executable or shared object requires N procedure 614 * linkage table entries, the link editor shall reserve 3*N 615 * words (12*N bytes) following the 18 reserved words. The 616 * first 2*N of these words are the procedure linkage table 617 * entries themselves. The static linker directs calls to bytes 618 * (72 + (i-1)*8), for i between 1 and N inclusive. The remaining 619 * N words (4*N bytes) are reserved for use by the dynamic linker.' 620 */ 621 622 /* 623 * Copy the absolute-call assembler stub into the first part of 624 * the reserved PLT area. 625 */ 626 memcpy(pltcall, _rtld_powerpc_pltcall, PLTCALL_SIZE); 627 628 /* 629 * Determine the address of the jumptable, which is the dyn-linker 630 * reserved area after the call cells. Write the absolute address 631 * of the jumptable into the absolute-call assembler code so it 632 * can determine this address. 633 */ 634 jmptab = obj->pltgot + JMPTAB_BASE(N); 635 pltcall[1] |= _ppc_ha(jmptab); /* addis 11,11,jmptab@ha */ 636 pltcall[2] |= _ppc_la(jmptab); /* lwz 11,jmptab@l(11) */ 637 638 /* 639 * Skip down 20 bytes into the initial reserved area and copy 640 * in the standard resolving assembler call. Into this assembler, 641 * insert the absolute address of the _rtld_bind_start routine 642 * and the address of the relocation object. 643 * 644 * We place pltlongresolve first, so it can fix up its arguments 645 * and then fall through to the regular PLT resolver. 646 */ 647 pltlongresolve = obj->pltgot + 5; 648 649 memcpy(pltlongresolve, _rtld_powerpc_pltlongresolve, 650 PLTLONGRESOLVE_SIZE); 651 pltlongresolve[0] |= _ppc_ha(jmptab); /* lis 12,jmptab@ha */ 652 pltlongresolve[1] |= _ppc_la(jmptab); /* addi 12,12,jmptab@l */ 653 654 pltresolve = pltlongresolve + PLTLONGRESOLVE_SIZE/sizeof(uint32_t); 655 memcpy(pltresolve, _rtld_powerpc_pltresolve, PLTRESOLVE_SIZE); 656 pltresolve[0] |= _ppc_ha(_rtld_bind_start); 657 pltresolve[1] |= _ppc_la(_rtld_bind_start); 658 pltresolve[3] |= _ppc_ha(obj); 659 pltresolve[4] |= _ppc_la(obj); 660 661 /* 662 * The icache will be sync'd in reloc_plt, which is called 663 * after all the slots have been updated 664 */ 665 } 666 667 void 668 ifunc_init(Elf_Auxinfo aux_info[__min_size(AT_COUNT)] __unused) 669 { 670 671 } 672 673 void 674 pre_init(void) 675 { 676 677 } 678 679 void 680 allocate_initial_tls(Obj_Entry *list) 681 { 682 Elf_Addr **tp; 683 684 /* 685 * Fix the size of the static TLS block by using the maximum 686 * offset allocated so far and adding a bit for dynamic modules to 687 * use. 688 */ 689 690 tls_static_space = tls_last_offset + tls_last_size + RTLD_STATIC_TLS_EXTRA; 691 692 tp = (Elf_Addr **)((char *) allocate_tls(list, NULL, TLS_TCB_SIZE, 8) 693 + TLS_TP_OFFSET + TLS_TCB_SIZE); 694 695 /* 696 * XXX gcc seems to ignore 'tp = _tp;' 697 */ 698 699 __asm __volatile("mr 2,%0" :: "r"(tp)); 700 } 701 702 void* 703 __tls_get_addr(tls_index* ti) 704 { 705 register Elf_Addr **tp; 706 char *p; 707 708 __asm __volatile("mr %0,2" : "=r"(tp)); 709 p = tls_get_addr_common((Elf_Addr**)((Elf_Addr)tp - TLS_TP_OFFSET 710 - TLS_TCB_SIZE), ti->ti_module, ti->ti_offset); 711 712 return (p + TLS_DTV_OFFSET); 713 } 714