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 #include <linux/mm.h> 65 #include <linux/slab.h> 66 67 #include <asm/pgtable.h> 68 #include <asm/unwind.h> 69 70 #if 0 71 #define DEBUGP printk 72 #else 73 #define DEBUGP(fmt...) 74 #endif 75 76 #define RELOC_REACHABLE(val, bits) \ 77 (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \ 78 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \ 79 0 : 1) 80 81 #define CHECK_RELOC(val, bits) \ 82 if (!RELOC_REACHABLE(val, bits)) { \ 83 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \ 84 me->name, strtab + sym->st_name, (unsigned long)val, bits); \ 85 return -ENOEXEC; \ 86 } 87 88 /* Maximum number of GOT entries. We use a long displacement ldd from 89 * the bottom of the table, which has a maximum signed displacement of 90 * 0x3fff; however, since we're only going forward, this becomes 91 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have 92 * at most 1023 entries. 93 * To overcome this 14bit displacement with some kernel modules, we'll 94 * use instead the unusal 16bit displacement method (see reassemble_16a) 95 * which gives us a maximum positive displacement of 0x7fff, and as such 96 * allows us to allocate up to 4095 GOT entries. */ 97 #define MAX_GOTS 4095 98 99 /* three functions to determine where in the module core 100 * or init pieces the location is */ 101 static inline int in_init(struct module *me, void *loc) 102 { 103 return (loc >= me->module_init && 104 loc <= (me->module_init + me->init_size)); 105 } 106 107 static inline int in_core(struct module *me, void *loc) 108 { 109 return (loc >= me->module_core && 110 loc <= (me->module_core + me->core_size)); 111 } 112 113 static inline int in_local(struct module *me, void *loc) 114 { 115 return in_init(me, loc) || in_core(me, loc); 116 } 117 118 #ifndef CONFIG_64BIT 119 struct got_entry { 120 Elf32_Addr addr; 121 }; 122 123 struct stub_entry { 124 Elf32_Word insns[2]; /* each stub entry has two insns */ 125 }; 126 #else 127 struct got_entry { 128 Elf64_Addr addr; 129 }; 130 131 struct stub_entry { 132 Elf64_Word insns[4]; /* each stub entry has four insns */ 133 }; 134 #endif 135 136 /* Field selection types defined by hppa */ 137 #define rnd(x) (((x)+0x1000)&~0x1fff) 138 /* fsel: full 32 bits */ 139 #define fsel(v,a) ((v)+(a)) 140 /* lsel: select left 21 bits */ 141 #define lsel(v,a) (((v)+(a))>>11) 142 /* rsel: select right 11 bits */ 143 #define rsel(v,a) (((v)+(a))&0x7ff) 144 /* lrsel with rounding of addend to nearest 8k */ 145 #define lrsel(v,a) (((v)+rnd(a))>>11) 146 /* rrsel with rounding of addend to nearest 8k */ 147 #define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a))) 148 149 #define mask(x,sz) ((x) & ~((1<<(sz))-1)) 150 151 152 /* The reassemble_* functions prepare an immediate value for 153 insertion into an opcode. pa-risc uses all sorts of weird bitfields 154 in the instruction to hold the value. */ 155 static inline int sign_unext(int x, int len) 156 { 157 int len_ones; 158 159 len_ones = (1 << len) - 1; 160 return x & len_ones; 161 } 162 163 static inline int low_sign_unext(int x, int len) 164 { 165 int sign, temp; 166 167 sign = (x >> (len-1)) & 1; 168 temp = sign_unext(x, len-1); 169 return (temp << 1) | sign; 170 } 171 172 static inline int reassemble_14(int as14) 173 { 174 return (((as14 & 0x1fff) << 1) | 175 ((as14 & 0x2000) >> 13)); 176 } 177 178 static inline int reassemble_16a(int as16) 179 { 180 int s, t; 181 182 /* Unusual 16-bit encoding, for wide mode only. */ 183 t = (as16 << 1) & 0xffff; 184 s = (as16 & 0x8000); 185 return (t ^ s ^ (s >> 1)) | (s >> 15); 186 } 187 188 189 static inline int reassemble_17(int as17) 190 { 191 return (((as17 & 0x10000) >> 16) | 192 ((as17 & 0x0f800) << 5) | 193 ((as17 & 0x00400) >> 8) | 194 ((as17 & 0x003ff) << 3)); 195 } 196 197 static inline int reassemble_21(int as21) 198 { 199 return (((as21 & 0x100000) >> 20) | 200 ((as21 & 0x0ffe00) >> 8) | 201 ((as21 & 0x000180) << 7) | 202 ((as21 & 0x00007c) << 14) | 203 ((as21 & 0x000003) << 12)); 204 } 205 206 static inline int reassemble_22(int as22) 207 { 208 return (((as22 & 0x200000) >> 21) | 209 ((as22 & 0x1f0000) << 5) | 210 ((as22 & 0x00f800) << 5) | 211 ((as22 & 0x000400) >> 8) | 212 ((as22 & 0x0003ff) << 3)); 213 } 214 215 void *module_alloc(unsigned long size) 216 { 217 /* using RWX means less protection for modules, but it's 218 * easier than trying to map the text, data, init_text and 219 * init_data correctly */ 220 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END, 221 GFP_KERNEL | __GFP_HIGHMEM, 222 PAGE_KERNEL_RWX, -1, 223 __builtin_return_address(0)); 224 } 225 226 #ifndef CONFIG_64BIT 227 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 228 { 229 return 0; 230 } 231 232 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 233 { 234 return 0; 235 } 236 237 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 238 { 239 unsigned long cnt = 0; 240 241 for (; n > 0; n--, rela++) 242 { 243 switch (ELF32_R_TYPE(rela->r_info)) { 244 case R_PARISC_PCREL17F: 245 case R_PARISC_PCREL22F: 246 cnt++; 247 } 248 } 249 250 return cnt; 251 } 252 #else 253 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) 254 { 255 unsigned long cnt = 0; 256 257 for (; n > 0; n--, rela++) 258 { 259 switch (ELF64_R_TYPE(rela->r_info)) { 260 case R_PARISC_LTOFF21L: 261 case R_PARISC_LTOFF14R: 262 case R_PARISC_PCREL22F: 263 cnt++; 264 } 265 } 266 267 return cnt; 268 } 269 270 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) 271 { 272 unsigned long cnt = 0; 273 274 for (; n > 0; n--, rela++) 275 { 276 switch (ELF64_R_TYPE(rela->r_info)) { 277 case R_PARISC_FPTR64: 278 cnt++; 279 } 280 } 281 282 return cnt; 283 } 284 285 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) 286 { 287 unsigned long cnt = 0; 288 289 for (; n > 0; n--, rela++) 290 { 291 switch (ELF64_R_TYPE(rela->r_info)) { 292 case R_PARISC_PCREL22F: 293 cnt++; 294 } 295 } 296 297 return cnt; 298 } 299 #endif 300 301 302 /* Free memory returned from module_alloc */ 303 void module_free(struct module *mod, void *module_region) 304 { 305 kfree(mod->arch.section); 306 mod->arch.section = NULL; 307 308 vfree(module_region); 309 } 310 311 /* Additional bytes needed in front of individual sections */ 312 unsigned int arch_mod_section_prepend(struct module *mod, 313 unsigned int section) 314 { 315 /* size needed for all stubs of this section (including 316 * one additional for correct alignment of the stubs) */ 317 return (mod->arch.section[section].stub_entries + 1) 318 * sizeof(struct stub_entry); 319 } 320 321 #define CONST 322 int module_frob_arch_sections(CONST Elf_Ehdr *hdr, 323 CONST Elf_Shdr *sechdrs, 324 CONST char *secstrings, 325 struct module *me) 326 { 327 unsigned long gots = 0, fdescs = 0, len; 328 unsigned int i; 329 330 len = hdr->e_shnum * sizeof(me->arch.section[0]); 331 me->arch.section = kzalloc(len, GFP_KERNEL); 332 if (!me->arch.section) 333 return -ENOMEM; 334 335 for (i = 1; i < hdr->e_shnum; i++) { 336 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr; 337 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels); 338 unsigned int count, s; 339 340 if (strncmp(secstrings + sechdrs[i].sh_name, 341 ".PARISC.unwind", 14) == 0) 342 me->arch.unwind_section = i; 343 344 if (sechdrs[i].sh_type != SHT_RELA) 345 continue; 346 347 /* some of these are not relevant for 32-bit/64-bit 348 * we leave them here to make the code common. the 349 * compiler will do its thing and optimize out the 350 * stuff we don't need 351 */ 352 gots += count_gots(rels, nrels); 353 fdescs += count_fdescs(rels, nrels); 354 355 /* XXX: By sorting the relocs and finding duplicate entries 356 * we could reduce the number of necessary stubs and save 357 * some memory. */ 358 count = count_stubs(rels, nrels); 359 if (!count) 360 continue; 361 362 /* so we need relocation stubs. reserve necessary memory. */ 363 /* sh_info gives the section for which we need to add stubs. */ 364 s = sechdrs[i].sh_info; 365 366 /* each code section should only have one relocation section */ 367 WARN_ON(me->arch.section[s].stub_entries); 368 369 /* store number of stubs we need for this section */ 370 me->arch.section[s].stub_entries += count; 371 } 372 373 /* align things a bit */ 374 me->core_size = ALIGN(me->core_size, 16); 375 me->arch.got_offset = me->core_size; 376 me->core_size += gots * sizeof(struct got_entry); 377 378 me->core_size = ALIGN(me->core_size, 16); 379 me->arch.fdesc_offset = me->core_size; 380 me->core_size += fdescs * sizeof(Elf_Fdesc); 381 382 me->arch.got_max = gots; 383 me->arch.fdesc_max = fdescs; 384 385 return 0; 386 } 387 388 #ifdef CONFIG_64BIT 389 static Elf64_Word get_got(struct module *me, unsigned long value, long addend) 390 { 391 unsigned int i; 392 struct got_entry *got; 393 394 value += addend; 395 396 BUG_ON(value == 0); 397 398 got = me->module_core + me->arch.got_offset; 399 for (i = 0; got[i].addr; i++) 400 if (got[i].addr == value) 401 goto out; 402 403 BUG_ON(++me->arch.got_count > me->arch.got_max); 404 405 got[i].addr = value; 406 out: 407 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry), 408 value); 409 return i * sizeof(struct got_entry); 410 } 411 #endif /* CONFIG_64BIT */ 412 413 #ifdef CONFIG_64BIT 414 static Elf_Addr get_fdesc(struct module *me, unsigned long value) 415 { 416 Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset; 417 418 if (!value) { 419 printk(KERN_ERR "%s: zero OPD requested!\n", me->name); 420 return 0; 421 } 422 423 /* Look for existing fdesc entry. */ 424 while (fdesc->addr) { 425 if (fdesc->addr == value) 426 return (Elf_Addr)fdesc; 427 fdesc++; 428 } 429 430 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max); 431 432 /* Create new one */ 433 fdesc->addr = value; 434 fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset; 435 return (Elf_Addr)fdesc; 436 } 437 #endif /* CONFIG_64BIT */ 438 439 enum elf_stub_type { 440 ELF_STUB_GOT, 441 ELF_STUB_MILLI, 442 ELF_STUB_DIRECT, 443 }; 444 445 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend, 446 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec) 447 { 448 struct stub_entry *stub; 449 int __maybe_unused d; 450 451 /* initialize stub_offset to point in front of the section */ 452 if (!me->arch.section[targetsec].stub_offset) { 453 loc0 -= (me->arch.section[targetsec].stub_entries + 1) * 454 sizeof(struct stub_entry); 455 /* get correct alignment for the stubs */ 456 loc0 = ALIGN(loc0, sizeof(struct stub_entry)); 457 me->arch.section[targetsec].stub_offset = loc0; 458 } 459 460 /* get address of stub entry */ 461 stub = (void *) me->arch.section[targetsec].stub_offset; 462 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry); 463 464 /* do not write outside available stub area */ 465 BUG_ON(0 == me->arch.section[targetsec].stub_entries--); 466 467 468 #ifndef CONFIG_64BIT 469 /* for 32-bit the stub looks like this: 470 * ldil L'XXX,%r1 471 * be,n R'XXX(%sr4,%r1) 472 */ 473 //value = *(unsigned long *)((value + addend) & ~3); /* why? */ 474 475 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */ 476 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */ 477 478 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 479 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4); 480 481 #else 482 /* for 64-bit we have three kinds of stubs: 483 * for normal function calls: 484 * ldd 0(%dp),%dp 485 * ldd 10(%dp), %r1 486 * bve (%r1) 487 * ldd 18(%dp), %dp 488 * 489 * for millicode: 490 * ldil 0, %r1 491 * ldo 0(%r1), %r1 492 * ldd 10(%r1), %r1 493 * bve,n (%r1) 494 * 495 * for direct branches (jumps between different section of the 496 * same module): 497 * ldil 0, %r1 498 * ldo 0(%r1), %r1 499 * bve,n (%r1) 500 */ 501 switch (stub_type) { 502 case ELF_STUB_GOT: 503 d = get_got(me, value, addend); 504 if (d <= 15) { 505 /* Format 5 */ 506 stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp */ 507 stub->insns[0] |= low_sign_unext(d, 5) << 16; 508 } else { 509 /* Format 3 */ 510 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */ 511 stub->insns[0] |= reassemble_16a(d); 512 } 513 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */ 514 stub->insns[2] = 0xe820d000; /* bve (%r1) */ 515 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */ 516 break; 517 case ELF_STUB_MILLI: 518 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 519 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 520 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */ 521 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */ 522 523 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 524 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 525 break; 526 case ELF_STUB_DIRECT: 527 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 528 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 529 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */ 530 531 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 532 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 533 break; 534 } 535 536 #endif 537 538 return (Elf_Addr)stub; 539 } 540 541 #ifndef CONFIG_64BIT 542 int apply_relocate_add(Elf_Shdr *sechdrs, 543 const char *strtab, 544 unsigned int symindex, 545 unsigned int relsec, 546 struct module *me) 547 { 548 int i; 549 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 550 Elf32_Sym *sym; 551 Elf32_Word *loc; 552 Elf32_Addr val; 553 Elf32_Sword addend; 554 Elf32_Addr dot; 555 Elf_Addr loc0; 556 unsigned int targetsec = sechdrs[relsec].sh_info; 557 //unsigned long dp = (unsigned long)$global$; 558 register unsigned long dp asm ("r27"); 559 560 DEBUGP("Applying relocate section %u to %u\n", relsec, 561 targetsec); 562 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 563 /* This is where to make the change */ 564 loc = (void *)sechdrs[targetsec].sh_addr 565 + rel[i].r_offset; 566 /* This is the start of the target section */ 567 loc0 = sechdrs[targetsec].sh_addr; 568 /* This is the symbol it is referring to */ 569 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 570 + ELF32_R_SYM(rel[i].r_info); 571 if (!sym->st_value) { 572 printk(KERN_WARNING "%s: Unknown symbol %s\n", 573 me->name, strtab + sym->st_name); 574 return -ENOENT; 575 } 576 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 577 dot = (Elf32_Addr)loc & ~0x03; 578 579 val = sym->st_value; 580 addend = rel[i].r_addend; 581 582 #if 0 583 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t : 584 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n", 585 strtab + sym->st_name, 586 (uint32_t)loc, val, addend, 587 r(R_PARISC_PLABEL32) 588 r(R_PARISC_DIR32) 589 r(R_PARISC_DIR21L) 590 r(R_PARISC_DIR14R) 591 r(R_PARISC_SEGREL32) 592 r(R_PARISC_DPREL21L) 593 r(R_PARISC_DPREL14R) 594 r(R_PARISC_PCREL17F) 595 r(R_PARISC_PCREL22F) 596 "UNKNOWN"); 597 #undef r 598 #endif 599 600 switch (ELF32_R_TYPE(rel[i].r_info)) { 601 case R_PARISC_PLABEL32: 602 /* 32-bit function address */ 603 /* no function descriptors... */ 604 *loc = fsel(val, addend); 605 break; 606 case R_PARISC_DIR32: 607 /* direct 32-bit ref */ 608 *loc = fsel(val, addend); 609 break; 610 case R_PARISC_DIR21L: 611 /* left 21 bits of effective address */ 612 val = lrsel(val, addend); 613 *loc = mask(*loc, 21) | reassemble_21(val); 614 break; 615 case R_PARISC_DIR14R: 616 /* right 14 bits of effective address */ 617 val = rrsel(val, addend); 618 *loc = mask(*loc, 14) | reassemble_14(val); 619 break; 620 case R_PARISC_SEGREL32: 621 /* 32-bit segment relative address */ 622 /* See note about special handling of SEGREL32 at 623 * the beginning of this file. 624 */ 625 *loc = fsel(val, addend); 626 break; 627 case R_PARISC_DPREL21L: 628 /* left 21 bit of relative address */ 629 val = lrsel(val - dp, addend); 630 *loc = mask(*loc, 21) | reassemble_21(val); 631 break; 632 case R_PARISC_DPREL14R: 633 /* right 14 bit of relative address */ 634 val = rrsel(val - dp, addend); 635 *loc = mask(*loc, 14) | reassemble_14(val); 636 break; 637 case R_PARISC_PCREL17F: 638 /* 17-bit PC relative address */ 639 /* calculate direct call offset */ 640 val += addend; 641 val = (val - dot - 8)/4; 642 if (!RELOC_REACHABLE(val, 17)) { 643 /* direct distance too far, create 644 * stub entry instead */ 645 val = get_stub(me, sym->st_value, addend, 646 ELF_STUB_DIRECT, loc0, targetsec); 647 val = (val - dot - 8)/4; 648 CHECK_RELOC(val, 17); 649 } 650 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val); 651 break; 652 case R_PARISC_PCREL22F: 653 /* 22-bit PC relative address; only defined for pa20 */ 654 /* calculate direct call offset */ 655 val += addend; 656 val = (val - dot - 8)/4; 657 if (!RELOC_REACHABLE(val, 22)) { 658 /* direct distance too far, create 659 * stub entry instead */ 660 val = get_stub(me, sym->st_value, addend, 661 ELF_STUB_DIRECT, loc0, targetsec); 662 val = (val - dot - 8)/4; 663 CHECK_RELOC(val, 22); 664 } 665 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 666 break; 667 668 default: 669 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 670 me->name, ELF32_R_TYPE(rel[i].r_info)); 671 return -ENOEXEC; 672 } 673 } 674 675 return 0; 676 } 677 678 #else 679 int apply_relocate_add(Elf_Shdr *sechdrs, 680 const char *strtab, 681 unsigned int symindex, 682 unsigned int relsec, 683 struct module *me) 684 { 685 int i; 686 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; 687 Elf64_Sym *sym; 688 Elf64_Word *loc; 689 Elf64_Xword *loc64; 690 Elf64_Addr val; 691 Elf64_Sxword addend; 692 Elf64_Addr dot; 693 Elf_Addr loc0; 694 unsigned int targetsec = sechdrs[relsec].sh_info; 695 696 DEBUGP("Applying relocate section %u to %u\n", relsec, 697 targetsec); 698 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 699 /* This is where to make the change */ 700 loc = (void *)sechdrs[targetsec].sh_addr 701 + rel[i].r_offset; 702 /* This is the start of the target section */ 703 loc0 = sechdrs[targetsec].sh_addr; 704 /* This is the symbol it is referring to */ 705 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr 706 + ELF64_R_SYM(rel[i].r_info); 707 if (!sym->st_value) { 708 printk(KERN_WARNING "%s: Unknown symbol %s\n", 709 me->name, strtab + sym->st_name); 710 return -ENOENT; 711 } 712 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 713 dot = (Elf64_Addr)loc & ~0x03; 714 loc64 = (Elf64_Xword *)loc; 715 716 val = sym->st_value; 717 addend = rel[i].r_addend; 718 719 #if 0 720 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t : 721 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n", 722 strtab + sym->st_name, 723 loc, val, addend, 724 r(R_PARISC_LTOFF14R) 725 r(R_PARISC_LTOFF21L) 726 r(R_PARISC_PCREL22F) 727 r(R_PARISC_DIR64) 728 r(R_PARISC_SEGREL32) 729 r(R_PARISC_FPTR64) 730 "UNKNOWN"); 731 #undef r 732 #endif 733 734 switch (ELF64_R_TYPE(rel[i].r_info)) { 735 case R_PARISC_LTOFF21L: 736 /* LT-relative; left 21 bits */ 737 val = get_got(me, val, addend); 738 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n", 739 strtab + sym->st_name, 740 loc, val); 741 val = lrsel(val, 0); 742 *loc = mask(*loc, 21) | reassemble_21(val); 743 break; 744 case R_PARISC_LTOFF14R: 745 /* L(ltoff(val+addend)) */ 746 /* LT-relative; right 14 bits */ 747 val = get_got(me, val, addend); 748 val = rrsel(val, 0); 749 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n", 750 strtab + sym->st_name, 751 loc, val); 752 *loc = mask(*loc, 14) | reassemble_14(val); 753 break; 754 case R_PARISC_PCREL22F: 755 /* PC-relative; 22 bits */ 756 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n", 757 strtab + sym->st_name, 758 loc, val); 759 val += addend; 760 /* can we reach it locally? */ 761 if (in_local(me, (void *)val)) { 762 /* this is the case where the symbol is local 763 * to the module, but in a different section, 764 * so stub the jump in case it's more than 22 765 * bits away */ 766 val = (val - dot - 8)/4; 767 if (!RELOC_REACHABLE(val, 22)) { 768 /* direct distance too far, create 769 * stub entry instead */ 770 val = get_stub(me, sym->st_value, 771 addend, ELF_STUB_DIRECT, 772 loc0, targetsec); 773 } else { 774 /* Ok, we can reach it directly. */ 775 val = sym->st_value; 776 val += addend; 777 } 778 } else { 779 val = sym->st_value; 780 if (strncmp(strtab + sym->st_name, "$$", 2) 781 == 0) 782 val = get_stub(me, val, addend, ELF_STUB_MILLI, 783 loc0, targetsec); 784 else 785 val = get_stub(me, val, addend, ELF_STUB_GOT, 786 loc0, targetsec); 787 } 788 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 789 strtab + sym->st_name, loc, sym->st_value, 790 addend, val); 791 val = (val - dot - 8)/4; 792 CHECK_RELOC(val, 22); 793 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 794 break; 795 case R_PARISC_DIR64: 796 /* 64-bit effective address */ 797 *loc64 = val + addend; 798 break; 799 case R_PARISC_SEGREL32: 800 /* 32-bit segment relative address */ 801 /* See note about special handling of SEGREL32 at 802 * the beginning of this file. 803 */ 804 *loc = fsel(val, addend); 805 break; 806 case R_PARISC_FPTR64: 807 /* 64-bit function address */ 808 if(in_local(me, (void *)(val + addend))) { 809 *loc64 = get_fdesc(me, val+addend); 810 DEBUGP("FDESC for %s at %p points to %lx\n", 811 strtab + sym->st_name, *loc64, 812 ((Elf_Fdesc *)*loc64)->addr); 813 } else { 814 /* if the symbol is not local to this 815 * module then val+addend is a pointer 816 * to the function descriptor */ 817 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n", 818 strtab + sym->st_name, 819 loc, val); 820 *loc64 = val + addend; 821 } 822 break; 823 824 default: 825 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n", 826 me->name, ELF64_R_TYPE(rel[i].r_info)); 827 return -ENOEXEC; 828 } 829 } 830 return 0; 831 } 832 #endif 833 834 static void 835 register_unwind_table(struct module *me, 836 const Elf_Shdr *sechdrs) 837 { 838 unsigned char *table, *end; 839 unsigned long gp; 840 841 if (!me->arch.unwind_section) 842 return; 843 844 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr; 845 end = table + sechdrs[me->arch.unwind_section].sh_size; 846 gp = (Elf_Addr)me->module_core + me->arch.got_offset; 847 848 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n", 849 me->arch.unwind_section, table, end, gp); 850 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end); 851 } 852 853 static void 854 deregister_unwind_table(struct module *me) 855 { 856 if (me->arch.unwind) 857 unwind_table_remove(me->arch.unwind); 858 } 859 860 int module_finalize(const Elf_Ehdr *hdr, 861 const Elf_Shdr *sechdrs, 862 struct module *me) 863 { 864 int i; 865 unsigned long nsyms; 866 const char *strtab = NULL; 867 Elf_Sym *newptr, *oldptr; 868 Elf_Shdr *symhdr = NULL; 869 #ifdef DEBUG 870 Elf_Fdesc *entry; 871 u32 *addr; 872 873 entry = (Elf_Fdesc *)me->init; 874 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry, 875 entry->gp, entry->addr); 876 addr = (u32 *)entry->addr; 877 printk("INSNS: %x %x %x %x\n", 878 addr[0], addr[1], addr[2], addr[3]); 879 printk("got entries used %ld, gots max %ld\n" 880 "fdescs used %ld, fdescs max %ld\n", 881 me->arch.got_count, me->arch.got_max, 882 me->arch.fdesc_count, me->arch.fdesc_max); 883 #endif 884 885 register_unwind_table(me, sechdrs); 886 887 /* haven't filled in me->symtab yet, so have to find it 888 * ourselves */ 889 for (i = 1; i < hdr->e_shnum; i++) { 890 if(sechdrs[i].sh_type == SHT_SYMTAB 891 && (sechdrs[i].sh_flags & SHF_ALLOC)) { 892 int strindex = sechdrs[i].sh_link; 893 /* FIXME: AWFUL HACK 894 * The cast is to drop the const from 895 * the sechdrs pointer */ 896 symhdr = (Elf_Shdr *)&sechdrs[i]; 897 strtab = (char *)sechdrs[strindex].sh_addr; 898 break; 899 } 900 } 901 902 DEBUGP("module %s: strtab %p, symhdr %p\n", 903 me->name, strtab, symhdr); 904 905 if(me->arch.got_count > MAX_GOTS) { 906 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n", 907 me->name, me->arch.got_count, MAX_GOTS); 908 return -EINVAL; 909 } 910 911 kfree(me->arch.section); 912 me->arch.section = NULL; 913 914 /* no symbol table */ 915 if(symhdr == NULL) 916 return 0; 917 918 oldptr = (void *)symhdr->sh_addr; 919 newptr = oldptr + 1; /* we start counting at 1 */ 920 nsyms = symhdr->sh_size / sizeof(Elf_Sym); 921 DEBUGP("OLD num_symtab %lu\n", nsyms); 922 923 for (i = 1; i < nsyms; i++) { 924 oldptr++; /* note, count starts at 1 so preincrement */ 925 if(strncmp(strtab + oldptr->st_name, 926 ".L", 2) == 0) 927 continue; 928 929 if(newptr != oldptr) 930 *newptr++ = *oldptr; 931 else 932 newptr++; 933 934 } 935 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; 936 DEBUGP("NEW num_symtab %lu\n", nsyms); 937 symhdr->sh_size = nsyms * sizeof(Elf_Sym); 938 return 0; 939 } 940 941 void module_arch_cleanup(struct module *mod) 942 { 943 deregister_unwind_table(mod); 944 } 945