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->init_layout.base; 46 * else 47 * val -= (uint32_t)me->core_layout.base; 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->init_layout.base && 104 loc <= (me->init_layout.base + me->init_layout.size)); 105 } 106 107 static inline int in_core(struct module *me, void *loc) 108 { 109 return (loc >= me->core_layout.base && 110 loc <= (me->core_layout.base + me->core_layout.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, 222 PAGE_KERNEL_RWX, 0, NUMA_NO_NODE, 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 void module_arch_freeing_init(struct module *mod) 302 { 303 kfree(mod->arch.section); 304 mod->arch.section = NULL; 305 } 306 307 /* Additional bytes needed in front of individual sections */ 308 unsigned int arch_mod_section_prepend(struct module *mod, 309 unsigned int section) 310 { 311 /* size needed for all stubs of this section (including 312 * one additional for correct alignment of the stubs) */ 313 return (mod->arch.section[section].stub_entries + 1) 314 * sizeof(struct stub_entry); 315 } 316 317 #define CONST 318 int module_frob_arch_sections(CONST Elf_Ehdr *hdr, 319 CONST Elf_Shdr *sechdrs, 320 CONST char *secstrings, 321 struct module *me) 322 { 323 unsigned long gots = 0, fdescs = 0, len; 324 unsigned int i; 325 326 len = hdr->e_shnum * sizeof(me->arch.section[0]); 327 me->arch.section = kzalloc(len, GFP_KERNEL); 328 if (!me->arch.section) 329 return -ENOMEM; 330 331 for (i = 1; i < hdr->e_shnum; i++) { 332 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr; 333 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels); 334 unsigned int count, s; 335 336 if (strncmp(secstrings + sechdrs[i].sh_name, 337 ".PARISC.unwind", 14) == 0) 338 me->arch.unwind_section = i; 339 340 if (sechdrs[i].sh_type != SHT_RELA) 341 continue; 342 343 /* some of these are not relevant for 32-bit/64-bit 344 * we leave them here to make the code common. the 345 * compiler will do its thing and optimize out the 346 * stuff we don't need 347 */ 348 gots += count_gots(rels, nrels); 349 fdescs += count_fdescs(rels, nrels); 350 351 /* XXX: By sorting the relocs and finding duplicate entries 352 * we could reduce the number of necessary stubs and save 353 * some memory. */ 354 count = count_stubs(rels, nrels); 355 if (!count) 356 continue; 357 358 /* so we need relocation stubs. reserve necessary memory. */ 359 /* sh_info gives the section for which we need to add stubs. */ 360 s = sechdrs[i].sh_info; 361 362 /* each code section should only have one relocation section */ 363 WARN_ON(me->arch.section[s].stub_entries); 364 365 /* store number of stubs we need for this section */ 366 me->arch.section[s].stub_entries += count; 367 } 368 369 /* align things a bit */ 370 me->core_layout.size = ALIGN(me->core_layout.size, 16); 371 me->arch.got_offset = me->core_layout.size; 372 me->core_layout.size += gots * sizeof(struct got_entry); 373 374 me->core_layout.size = ALIGN(me->core_layout.size, 16); 375 me->arch.fdesc_offset = me->core_layout.size; 376 me->core_layout.size += fdescs * sizeof(Elf_Fdesc); 377 378 me->arch.got_max = gots; 379 me->arch.fdesc_max = fdescs; 380 381 return 0; 382 } 383 384 #ifdef CONFIG_64BIT 385 static Elf64_Word get_got(struct module *me, unsigned long value, long addend) 386 { 387 unsigned int i; 388 struct got_entry *got; 389 390 value += addend; 391 392 BUG_ON(value == 0); 393 394 got = me->core_layout.base + me->arch.got_offset; 395 for (i = 0; got[i].addr; i++) 396 if (got[i].addr == value) 397 goto out; 398 399 BUG_ON(++me->arch.got_count > me->arch.got_max); 400 401 got[i].addr = value; 402 out: 403 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry), 404 value); 405 return i * sizeof(struct got_entry); 406 } 407 #endif /* CONFIG_64BIT */ 408 409 #ifdef CONFIG_64BIT 410 static Elf_Addr get_fdesc(struct module *me, unsigned long value) 411 { 412 Elf_Fdesc *fdesc = me->core_layout.base + me->arch.fdesc_offset; 413 414 if (!value) { 415 printk(KERN_ERR "%s: zero OPD requested!\n", me->name); 416 return 0; 417 } 418 419 /* Look for existing fdesc entry. */ 420 while (fdesc->addr) { 421 if (fdesc->addr == value) 422 return (Elf_Addr)fdesc; 423 fdesc++; 424 } 425 426 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max); 427 428 /* Create new one */ 429 fdesc->addr = value; 430 fdesc->gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset; 431 return (Elf_Addr)fdesc; 432 } 433 #endif /* CONFIG_64BIT */ 434 435 enum elf_stub_type { 436 ELF_STUB_GOT, 437 ELF_STUB_MILLI, 438 ELF_STUB_DIRECT, 439 }; 440 441 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend, 442 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec) 443 { 444 struct stub_entry *stub; 445 int __maybe_unused d; 446 447 /* initialize stub_offset to point in front of the section */ 448 if (!me->arch.section[targetsec].stub_offset) { 449 loc0 -= (me->arch.section[targetsec].stub_entries + 1) * 450 sizeof(struct stub_entry); 451 /* get correct alignment for the stubs */ 452 loc0 = ALIGN(loc0, sizeof(struct stub_entry)); 453 me->arch.section[targetsec].stub_offset = loc0; 454 } 455 456 /* get address of stub entry */ 457 stub = (void *) me->arch.section[targetsec].stub_offset; 458 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry); 459 460 /* do not write outside available stub area */ 461 BUG_ON(0 == me->arch.section[targetsec].stub_entries--); 462 463 464 #ifndef CONFIG_64BIT 465 /* for 32-bit the stub looks like this: 466 * ldil L'XXX,%r1 467 * be,n R'XXX(%sr4,%r1) 468 */ 469 //value = *(unsigned long *)((value + addend) & ~3); /* why? */ 470 471 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */ 472 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */ 473 474 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 475 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4); 476 477 #else 478 /* for 64-bit we have three kinds of stubs: 479 * for normal function calls: 480 * ldd 0(%dp),%dp 481 * ldd 10(%dp), %r1 482 * bve (%r1) 483 * ldd 18(%dp), %dp 484 * 485 * for millicode: 486 * ldil 0, %r1 487 * ldo 0(%r1), %r1 488 * ldd 10(%r1), %r1 489 * bve,n (%r1) 490 * 491 * for direct branches (jumps between different section of the 492 * same module): 493 * ldil 0, %r1 494 * ldo 0(%r1), %r1 495 * bve,n (%r1) 496 */ 497 switch (stub_type) { 498 case ELF_STUB_GOT: 499 d = get_got(me, value, addend); 500 if (d <= 15) { 501 /* Format 5 */ 502 stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp */ 503 stub->insns[0] |= low_sign_unext(d, 5) << 16; 504 } else { 505 /* Format 3 */ 506 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */ 507 stub->insns[0] |= reassemble_16a(d); 508 } 509 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */ 510 stub->insns[2] = 0xe820d000; /* bve (%r1) */ 511 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */ 512 break; 513 case ELF_STUB_MILLI: 514 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 515 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 516 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */ 517 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */ 518 519 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 520 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 521 break; 522 case ELF_STUB_DIRECT: 523 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ 524 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ 525 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */ 526 527 stub->insns[0] |= reassemble_21(lrsel(value, addend)); 528 stub->insns[1] |= reassemble_14(rrsel(value, addend)); 529 break; 530 } 531 532 #endif 533 534 return (Elf_Addr)stub; 535 } 536 537 #ifndef CONFIG_64BIT 538 int apply_relocate_add(Elf_Shdr *sechdrs, 539 const char *strtab, 540 unsigned int symindex, 541 unsigned int relsec, 542 struct module *me) 543 { 544 int i; 545 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 546 Elf32_Sym *sym; 547 Elf32_Word *loc; 548 Elf32_Addr val; 549 Elf32_Sword addend; 550 Elf32_Addr dot; 551 Elf_Addr loc0; 552 unsigned int targetsec = sechdrs[relsec].sh_info; 553 //unsigned long dp = (unsigned long)$global$; 554 register unsigned long dp asm ("r27"); 555 556 DEBUGP("Applying relocate section %u to %u\n", relsec, 557 targetsec); 558 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 559 /* This is where to make the change */ 560 loc = (void *)sechdrs[targetsec].sh_addr 561 + rel[i].r_offset; 562 /* This is the start of the target section */ 563 loc0 = sechdrs[targetsec].sh_addr; 564 /* This is the symbol it is referring to */ 565 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 566 + ELF32_R_SYM(rel[i].r_info); 567 if (!sym->st_value) { 568 printk(KERN_WARNING "%s: Unknown symbol %s\n", 569 me->name, strtab + sym->st_name); 570 return -ENOENT; 571 } 572 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 573 dot = (Elf32_Addr)loc & ~0x03; 574 575 val = sym->st_value; 576 addend = rel[i].r_addend; 577 578 #if 0 579 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t : 580 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n", 581 strtab + sym->st_name, 582 (uint32_t)loc, val, addend, 583 r(R_PARISC_PLABEL32) 584 r(R_PARISC_DIR32) 585 r(R_PARISC_DIR21L) 586 r(R_PARISC_DIR14R) 587 r(R_PARISC_SEGREL32) 588 r(R_PARISC_DPREL21L) 589 r(R_PARISC_DPREL14R) 590 r(R_PARISC_PCREL17F) 591 r(R_PARISC_PCREL22F) 592 "UNKNOWN"); 593 #undef r 594 #endif 595 596 switch (ELF32_R_TYPE(rel[i].r_info)) { 597 case R_PARISC_PLABEL32: 598 /* 32-bit function address */ 599 /* no function descriptors... */ 600 *loc = fsel(val, addend); 601 break; 602 case R_PARISC_DIR32: 603 /* direct 32-bit ref */ 604 *loc = fsel(val, addend); 605 break; 606 case R_PARISC_DIR21L: 607 /* left 21 bits of effective address */ 608 val = lrsel(val, addend); 609 *loc = mask(*loc, 21) | reassemble_21(val); 610 break; 611 case R_PARISC_DIR14R: 612 /* right 14 bits of effective address */ 613 val = rrsel(val, addend); 614 *loc = mask(*loc, 14) | reassemble_14(val); 615 break; 616 case R_PARISC_SEGREL32: 617 /* 32-bit segment relative address */ 618 /* See note about special handling of SEGREL32 at 619 * the beginning of this file. 620 */ 621 *loc = fsel(val, addend); 622 break; 623 case R_PARISC_SECREL32: 624 /* 32-bit section relative address. */ 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 case R_PARISC_PCREL32: 668 /* 32-bit PC relative address */ 669 *loc = val - dot - 8 + addend; 670 break; 671 672 default: 673 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 674 me->name, ELF32_R_TYPE(rel[i].r_info)); 675 return -ENOEXEC; 676 } 677 } 678 679 return 0; 680 } 681 682 #else 683 int apply_relocate_add(Elf_Shdr *sechdrs, 684 const char *strtab, 685 unsigned int symindex, 686 unsigned int relsec, 687 struct module *me) 688 { 689 int i; 690 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; 691 Elf64_Sym *sym; 692 Elf64_Word *loc; 693 Elf64_Xword *loc64; 694 Elf64_Addr val; 695 Elf64_Sxword addend; 696 Elf64_Addr dot; 697 Elf_Addr loc0; 698 unsigned int targetsec = sechdrs[relsec].sh_info; 699 700 DEBUGP("Applying relocate section %u to %u\n", relsec, 701 targetsec); 702 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 703 /* This is where to make the change */ 704 loc = (void *)sechdrs[targetsec].sh_addr 705 + rel[i].r_offset; 706 /* This is the start of the target section */ 707 loc0 = sechdrs[targetsec].sh_addr; 708 /* This is the symbol it is referring to */ 709 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr 710 + ELF64_R_SYM(rel[i].r_info); 711 if (!sym->st_value) { 712 printk(KERN_WARNING "%s: Unknown symbol %s\n", 713 me->name, strtab + sym->st_name); 714 return -ENOENT; 715 } 716 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; 717 dot = (Elf64_Addr)loc & ~0x03; 718 loc64 = (Elf64_Xword *)loc; 719 720 val = sym->st_value; 721 addend = rel[i].r_addend; 722 723 #if 0 724 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t : 725 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n", 726 strtab + sym->st_name, 727 loc, val, addend, 728 r(R_PARISC_LTOFF14R) 729 r(R_PARISC_LTOFF21L) 730 r(R_PARISC_PCREL22F) 731 r(R_PARISC_DIR64) 732 r(R_PARISC_SEGREL32) 733 r(R_PARISC_FPTR64) 734 "UNKNOWN"); 735 #undef r 736 #endif 737 738 switch (ELF64_R_TYPE(rel[i].r_info)) { 739 case R_PARISC_LTOFF21L: 740 /* LT-relative; left 21 bits */ 741 val = get_got(me, val, addend); 742 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n", 743 strtab + sym->st_name, 744 loc, val); 745 val = lrsel(val, 0); 746 *loc = mask(*loc, 21) | reassemble_21(val); 747 break; 748 case R_PARISC_LTOFF14R: 749 /* L(ltoff(val+addend)) */ 750 /* LT-relative; right 14 bits */ 751 val = get_got(me, val, addend); 752 val = rrsel(val, 0); 753 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n", 754 strtab + sym->st_name, 755 loc, val); 756 *loc = mask(*loc, 14) | reassemble_14(val); 757 break; 758 case R_PARISC_PCREL22F: 759 /* PC-relative; 22 bits */ 760 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n", 761 strtab + sym->st_name, 762 loc, val); 763 val += addend; 764 /* can we reach it locally? */ 765 if (in_local(me, (void *)val)) { 766 /* this is the case where the symbol is local 767 * to the module, but in a different section, 768 * so stub the jump in case it's more than 22 769 * bits away */ 770 val = (val - dot - 8)/4; 771 if (!RELOC_REACHABLE(val, 22)) { 772 /* direct distance too far, create 773 * stub entry instead */ 774 val = get_stub(me, sym->st_value, 775 addend, ELF_STUB_DIRECT, 776 loc0, targetsec); 777 } else { 778 /* Ok, we can reach it directly. */ 779 val = sym->st_value; 780 val += addend; 781 } 782 } else { 783 val = sym->st_value; 784 if (strncmp(strtab + sym->st_name, "$$", 2) 785 == 0) 786 val = get_stub(me, val, addend, ELF_STUB_MILLI, 787 loc0, targetsec); 788 else 789 val = get_stub(me, val, addend, ELF_STUB_GOT, 790 loc0, targetsec); 791 } 792 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 793 strtab + sym->st_name, loc, sym->st_value, 794 addend, val); 795 val = (val - dot - 8)/4; 796 CHECK_RELOC(val, 22); 797 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); 798 break; 799 case R_PARISC_PCREL32: 800 /* 32-bit PC relative address */ 801 *loc = val - dot - 8 + addend; 802 break; 803 case R_PARISC_DIR64: 804 /* 64-bit effective address */ 805 *loc64 = val + addend; 806 break; 807 case R_PARISC_SEGREL32: 808 /* 32-bit segment relative address */ 809 /* See note about special handling of SEGREL32 at 810 * the beginning of this file. 811 */ 812 *loc = fsel(val, addend); 813 break; 814 case R_PARISC_SECREL32: 815 /* 32-bit section relative address. */ 816 *loc = fsel(val, addend); 817 break; 818 case R_PARISC_FPTR64: 819 /* 64-bit function address */ 820 if(in_local(me, (void *)(val + addend))) { 821 *loc64 = get_fdesc(me, val+addend); 822 DEBUGP("FDESC for %s at %p points to %lx\n", 823 strtab + sym->st_name, *loc64, 824 ((Elf_Fdesc *)*loc64)->addr); 825 } else { 826 /* if the symbol is not local to this 827 * module then val+addend is a pointer 828 * to the function descriptor */ 829 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n", 830 strtab + sym->st_name, 831 loc, val); 832 *loc64 = val + addend; 833 } 834 break; 835 836 default: 837 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n", 838 me->name, ELF64_R_TYPE(rel[i].r_info)); 839 return -ENOEXEC; 840 } 841 } 842 return 0; 843 } 844 #endif 845 846 static void 847 register_unwind_table(struct module *me, 848 const Elf_Shdr *sechdrs) 849 { 850 unsigned char *table, *end; 851 unsigned long gp; 852 853 if (!me->arch.unwind_section) 854 return; 855 856 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr; 857 end = table + sechdrs[me->arch.unwind_section].sh_size; 858 gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset; 859 860 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n", 861 me->arch.unwind_section, table, end, gp); 862 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end); 863 } 864 865 static void 866 deregister_unwind_table(struct module *me) 867 { 868 if (me->arch.unwind) 869 unwind_table_remove(me->arch.unwind); 870 } 871 872 int module_finalize(const Elf_Ehdr *hdr, 873 const Elf_Shdr *sechdrs, 874 struct module *me) 875 { 876 int i; 877 unsigned long nsyms; 878 const char *strtab = NULL; 879 Elf_Sym *newptr, *oldptr; 880 Elf_Shdr *symhdr = NULL; 881 #ifdef DEBUG 882 Elf_Fdesc *entry; 883 u32 *addr; 884 885 entry = (Elf_Fdesc *)me->init; 886 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry, 887 entry->gp, entry->addr); 888 addr = (u32 *)entry->addr; 889 printk("INSNS: %x %x %x %x\n", 890 addr[0], addr[1], addr[2], addr[3]); 891 printk("got entries used %ld, gots max %ld\n" 892 "fdescs used %ld, fdescs max %ld\n", 893 me->arch.got_count, me->arch.got_max, 894 me->arch.fdesc_count, me->arch.fdesc_max); 895 #endif 896 897 register_unwind_table(me, sechdrs); 898 899 /* haven't filled in me->symtab yet, so have to find it 900 * ourselves */ 901 for (i = 1; i < hdr->e_shnum; i++) { 902 if(sechdrs[i].sh_type == SHT_SYMTAB 903 && (sechdrs[i].sh_flags & SHF_ALLOC)) { 904 int strindex = sechdrs[i].sh_link; 905 /* FIXME: AWFUL HACK 906 * The cast is to drop the const from 907 * the sechdrs pointer */ 908 symhdr = (Elf_Shdr *)&sechdrs[i]; 909 strtab = (char *)sechdrs[strindex].sh_addr; 910 break; 911 } 912 } 913 914 DEBUGP("module %s: strtab %p, symhdr %p\n", 915 me->name, strtab, symhdr); 916 917 if(me->arch.got_count > MAX_GOTS) { 918 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n", 919 me->name, me->arch.got_count, MAX_GOTS); 920 return -EINVAL; 921 } 922 923 kfree(me->arch.section); 924 me->arch.section = NULL; 925 926 /* no symbol table */ 927 if(symhdr == NULL) 928 return 0; 929 930 oldptr = (void *)symhdr->sh_addr; 931 newptr = oldptr + 1; /* we start counting at 1 */ 932 nsyms = symhdr->sh_size / sizeof(Elf_Sym); 933 DEBUGP("OLD num_symtab %lu\n", nsyms); 934 935 for (i = 1; i < nsyms; i++) { 936 oldptr++; /* note, count starts at 1 so preincrement */ 937 if(strncmp(strtab + oldptr->st_name, 938 ".L", 2) == 0) 939 continue; 940 941 if(newptr != oldptr) 942 *newptr++ = *oldptr; 943 else 944 newptr++; 945 946 } 947 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; 948 DEBUGP("NEW num_symtab %lu\n", nsyms); 949 symhdr->sh_size = nsyms * sizeof(Elf_Sym); 950 return 0; 951 } 952 953 void module_arch_cleanup(struct module *mod) 954 { 955 deregister_unwind_table(mod); 956 } 957