elf64-s390.c revision 99461
1/* IBM S/390-specific support for 64-bit ELF 2 Copyright 2000, 2001, 2002 Free Software Foundation, Inc. 3 Contributed Martin Schwidefsky (schwidefsky@de.ibm.com). 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 20 02111-1307, USA. */ 21 22#include "bfd.h" 23#include "sysdep.h" 24#include "bfdlink.h" 25#include "libbfd.h" 26#include "elf-bfd.h" 27 28static reloc_howto_type *elf_s390_reloc_type_lookup 29 PARAMS ((bfd *, bfd_reloc_code_real_type)); 30static void elf_s390_info_to_howto 31 PARAMS ((bfd *, arelent *, Elf_Internal_Rela *)); 32static boolean elf_s390_is_local_label_name 33 PARAMS ((bfd *, const char *)); 34static struct bfd_hash_entry *link_hash_newfunc 35 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *)); 36static struct bfd_link_hash_table *elf_s390_link_hash_table_create 37 PARAMS ((bfd *)); 38static boolean create_got_section 39 PARAMS((bfd *, struct bfd_link_info *)); 40static boolean elf_s390_create_dynamic_sections 41 PARAMS((bfd *, struct bfd_link_info *)); 42static void elf_s390_copy_indirect_symbol 43 PARAMS ((struct elf_link_hash_entry *, struct elf_link_hash_entry *)); 44static boolean elf_s390_check_relocs 45 PARAMS ((bfd *, struct bfd_link_info *, asection *, 46 const Elf_Internal_Rela *)); 47static asection *elf_s390_gc_mark_hook 48 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *, 49 struct elf_link_hash_entry *, Elf_Internal_Sym *)); 50static boolean elf_s390_gc_sweep_hook 51 PARAMS ((bfd *, struct bfd_link_info *, asection *, 52 const Elf_Internal_Rela *)); 53static boolean elf_s390_adjust_dynamic_symbol 54 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *)); 55static boolean allocate_dynrelocs 56 PARAMS ((struct elf_link_hash_entry *, PTR)); 57static boolean readonly_dynrelocs 58 PARAMS ((struct elf_link_hash_entry *, PTR)); 59static boolean elf_s390_size_dynamic_sections 60 PARAMS ((bfd *, struct bfd_link_info *)); 61static boolean elf_s390_relocate_section 62 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, 63 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **)); 64static boolean elf_s390_finish_dynamic_symbol 65 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *, 66 Elf_Internal_Sym *)); 67static enum elf_reloc_type_class elf_s390_reloc_type_class 68 PARAMS ((const Elf_Internal_Rela *)); 69static boolean elf_s390_finish_dynamic_sections 70 PARAMS ((bfd *, struct bfd_link_info *)); 71static boolean elf_s390_object_p PARAMS ((bfd *)); 72 73#define USE_RELA 1 /* We want RELA relocations, not REL. */ 74 75#include "elf/s390.h" 76 77/* In case we're on a 32-bit machine, construct a 64-bit "-1" value 78 from smaller values. Start with zero, widen, *then* decrement. */ 79#define MINUS_ONE (((bfd_vma)0) - 1) 80 81/* The relocation "howto" table. */ 82static reloc_howto_type elf_howto_table[] = 83{ 84 HOWTO (R_390_NONE, /* type */ 85 0, /* rightshift */ 86 0, /* size (0 = byte, 1 = short, 2 = long) */ 87 0, /* bitsize */ 88 false, /* pc_relative */ 89 0, /* bitpos */ 90 complain_overflow_dont, /* complain_on_overflow */ 91 bfd_elf_generic_reloc, /* special_function */ 92 "R_390_NONE", /* name */ 93 false, /* partial_inplace */ 94 0, /* src_mask */ 95 0, /* dst_mask */ 96 false), /* pcrel_offset */ 97 98 HOWTO(R_390_8, 0, 0, 8, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_8", false, 0,0x000000ff, false), 99 HOWTO(R_390_12, 0, 1, 12, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_390_12", false, 0,0x00000fff, false), 100 HOWTO(R_390_16, 0, 1, 16, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_16", false, 0,0x0000ffff, false), 101 HOWTO(R_390_32, 0, 2, 32, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_32", false, 0,0xffffffff, false), 102 HOWTO(R_390_PC32, 0, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PC32", false, 0,0xffffffff, true), 103 HOWTO(R_390_GOT12, 0, 1, 12, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_390_GOT12", false, 0,0x00000fff, false), 104 HOWTO(R_390_GOT32, 0, 2, 32, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOT32", false, 0,0xffffffff, false), 105 HOWTO(R_390_PLT32, 0, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PLT32", false, 0,0xffffffff, true), 106 HOWTO(R_390_COPY, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_COPY", false, 0,MINUS_ONE, false), 107 HOWTO(R_390_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GLOB_DAT",false, 0,MINUS_ONE, false), 108 HOWTO(R_390_JMP_SLOT, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_JMP_SLOT",false, 0,MINUS_ONE, false), 109 HOWTO(R_390_RELATIVE, 0, 4, 64, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_RELATIVE",false, 0,MINUS_ONE, false), 110 HOWTO(R_390_GOTOFF, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOTOFF", false, 0,MINUS_ONE, false), 111 HOWTO(R_390_GOTPC, 0, 4, 64, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOTPC", false, 0,MINUS_ONE, true), 112 HOWTO(R_390_GOT16, 0, 1, 16, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOT16", false, 0,0x0000ffff, false), 113 HOWTO(R_390_PC16, 0, 1, 16, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PC16", false, 0,0x0000ffff, true), 114 HOWTO(R_390_PC16DBL, 1, 1, 16, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PC16DBL", false, 0,0x0000ffff, true), 115 HOWTO(R_390_PLT16DBL, 1, 1, 16, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PLT16DBL", false, 0,0x0000ffff, true), 116 HOWTO(R_390_PC32DBL, 1, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PC32DBL", false, 0,0xffffffff, true), 117 HOWTO(R_390_PLT32DBL, 1, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PLT32DBL", false, 0,0xffffffff, true), 118 HOWTO(R_390_GOTPCDBL, 1, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOTPCDBL", false, 0,MINUS_ONE, true), 119 HOWTO(R_390_64, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_64", false, 0,MINUS_ONE, false), 120 HOWTO(R_390_PC64, 0, 4, 64, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PC64", false, 0,MINUS_ONE, true), 121 HOWTO(R_390_GOT64, 0, 4, 64, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOT64", false, 0,MINUS_ONE, false), 122 HOWTO(R_390_PLT64, 0, 4, 64, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_PLT64", false, 0,MINUS_ONE, true), 123 HOWTO(R_390_GOTENT, 1, 2, 32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_390_GOTENT", false, 0,MINUS_ONE, true), 124}; 125 126/* GNU extension to record C++ vtable hierarchy. */ 127static reloc_howto_type elf64_s390_vtinherit_howto = 128 HOWTO (R_390_GNU_VTINHERIT, 0,4,0,false,0,complain_overflow_dont, NULL, "R_390_GNU_VTINHERIT", false,0, 0, false); 129static reloc_howto_type elf64_s390_vtentry_howto = 130 HOWTO (R_390_GNU_VTENTRY, 0,4,0,false,0,complain_overflow_dont, _bfd_elf_rel_vtable_reloc_fn,"R_390_GNU_VTENTRY", false,0,0, false); 131 132static reloc_howto_type * 133elf_s390_reloc_type_lookup (abfd, code) 134 bfd *abfd ATTRIBUTE_UNUSED; 135 bfd_reloc_code_real_type code; 136{ 137 switch (code) 138 { 139 case BFD_RELOC_NONE: 140 return &elf_howto_table[(int) R_390_NONE]; 141 case BFD_RELOC_8: 142 return &elf_howto_table[(int) R_390_8]; 143 case BFD_RELOC_390_12: 144 return &elf_howto_table[(int) R_390_12]; 145 case BFD_RELOC_16: 146 return &elf_howto_table[(int) R_390_16]; 147 case BFD_RELOC_32: 148 return &elf_howto_table[(int) R_390_32]; 149 case BFD_RELOC_CTOR: 150 return &elf_howto_table[(int) R_390_32]; 151 case BFD_RELOC_32_PCREL: 152 return &elf_howto_table[(int) R_390_PC32]; 153 case BFD_RELOC_390_GOT12: 154 return &elf_howto_table[(int) R_390_GOT12]; 155 case BFD_RELOC_32_GOT_PCREL: 156 return &elf_howto_table[(int) R_390_GOT32]; 157 case BFD_RELOC_390_PLT32: 158 return &elf_howto_table[(int) R_390_PLT32]; 159 case BFD_RELOC_390_COPY: 160 return &elf_howto_table[(int) R_390_COPY]; 161 case BFD_RELOC_390_GLOB_DAT: 162 return &elf_howto_table[(int) R_390_GLOB_DAT]; 163 case BFD_RELOC_390_JMP_SLOT: 164 return &elf_howto_table[(int) R_390_JMP_SLOT]; 165 case BFD_RELOC_390_RELATIVE: 166 return &elf_howto_table[(int) R_390_RELATIVE]; 167 case BFD_RELOC_32_GOTOFF: 168 return &elf_howto_table[(int) R_390_GOTOFF]; 169 case BFD_RELOC_390_GOTPC: 170 return &elf_howto_table[(int) R_390_GOTPC]; 171 case BFD_RELOC_390_GOT16: 172 return &elf_howto_table[(int) R_390_GOT16]; 173 case BFD_RELOC_16_PCREL: 174 return &elf_howto_table[(int) R_390_PC16]; 175 case BFD_RELOC_390_PC16DBL: 176 return &elf_howto_table[(int) R_390_PC16DBL]; 177 case BFD_RELOC_390_PLT16DBL: 178 return &elf_howto_table[(int) R_390_PLT16DBL]; 179 case BFD_RELOC_VTABLE_INHERIT: 180 return &elf64_s390_vtinherit_howto; 181 case BFD_RELOC_VTABLE_ENTRY: 182 return &elf64_s390_vtentry_howto; 183 case BFD_RELOC_390_PC32DBL: 184 return &elf_howto_table[(int) R_390_PC32DBL]; 185 case BFD_RELOC_390_PLT32DBL: 186 return &elf_howto_table[(int) R_390_PLT32DBL]; 187 case BFD_RELOC_390_GOTPCDBL: 188 return &elf_howto_table[(int) R_390_GOTPCDBL]; 189 case BFD_RELOC_64: 190 return &elf_howto_table[(int) R_390_64]; 191 case BFD_RELOC_64_PCREL: 192 return &elf_howto_table[(int) R_390_PC64]; 193 case BFD_RELOC_390_GOT64: 194 return &elf_howto_table[(int) R_390_GOT64]; 195 case BFD_RELOC_390_PLT64: 196 return &elf_howto_table[(int) R_390_PLT64]; 197 case BFD_RELOC_390_GOTENT: 198 return &elf_howto_table[(int) R_390_GOTENT]; 199 default: 200 break; 201 } 202 return 0; 203} 204 205/* We need to use ELF64_R_TYPE so we have our own copy of this function, 206 and elf64-s390.c has its own copy. */ 207 208static void 209elf_s390_info_to_howto (abfd, cache_ptr, dst) 210 bfd *abfd ATTRIBUTE_UNUSED; 211 arelent *cache_ptr; 212 Elf_Internal_Rela *dst; 213{ 214 switch (ELF64_R_TYPE(dst->r_info)) 215 { 216 case R_390_GNU_VTINHERIT: 217 cache_ptr->howto = &elf64_s390_vtinherit_howto; 218 break; 219 220 case R_390_GNU_VTENTRY: 221 cache_ptr->howto = &elf64_s390_vtentry_howto; 222 break; 223 224 default: 225 BFD_ASSERT (ELF64_R_TYPE(dst->r_info) < (unsigned int) R_390_max); 226 cache_ptr->howto = &elf_howto_table[ELF64_R_TYPE(dst->r_info)]; 227 } 228} 229 230static boolean 231elf_s390_is_local_label_name (abfd, name) 232 bfd *abfd; 233 const char *name; 234{ 235 if (name[0] == '.' && (name[1] == 'X' || name[1] == 'L')) 236 return true; 237 238 return _bfd_elf_is_local_label_name (abfd, name); 239} 240 241/* Functions for the 390 ELF linker. */ 242 243/* The name of the dynamic interpreter. This is put in the .interp 244 section. */ 245 246#define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1" 247 248/* The size in bytes of the first entry in the procedure linkage table. */ 249#define PLT_FIRST_ENTRY_SIZE 32 250/* The size in bytes of an entry in the procedure linkage table. */ 251#define PLT_ENTRY_SIZE 32 252 253#define GOT_ENTRY_SIZE 8 254 255/* The first three entries in a procedure linkage table are reserved, 256 and the initial contents are unimportant (we zero them out). 257 Subsequent entries look like this. See the SVR4 ABI 386 258 supplement to see how this works. */ 259 260/* For the s390, simple addr offset can only be 0 - 4096. 261 To use the full 16777216 TB address space, several instructions 262 are needed to load an address in a register and execute 263 a branch( or just saving the address) 264 265 Furthermore, only r 0 and 1 are free to use!!! */ 266 267/* The first 3 words in the GOT are then reserved. 268 Word 0 is the address of the dynamic table. 269 Word 1 is a pointer to a structure describing the object 270 Word 2 is used to point to the loader entry address. 271 272 The code for PLT entries looks like this: 273 274 The GOT holds the address in the PLT to be executed. 275 The loader then gets: 276 24(15) = Pointer to the structure describing the object. 277 28(15) = Offset in symbol table 278 The loader must then find the module where the function is 279 and insert the address in the GOT. 280 281 PLT1: LARL 1,<fn>@GOTENT # 6 bytes Load address of GOT entry in r1 282 LG 1,0(1) # 6 bytes Load address from GOT in r1 283 BCR 15,1 # 2 bytes Jump to address 284 RET1: BASR 1,0 # 2 bytes Return from GOT 1st time 285 LGF 1,12(1) # 6 bytes Load offset in symbl table in r1 286 BRCL 15,-x # 6 bytes Jump to start of PLT 287 .long ? # 4 bytes offset into symbol table 288 289 Total = 32 bytes per PLT entry 290 Fixup at offset 2: relative address to GOT entry 291 Fixup at offset 22: relative branch to PLT0 292 Fixup at offset 28: 32 bit offset into symbol table 293 294 A 32 bit offset into the symbol table is enough. It allows for symbol 295 tables up to a size of 2 gigabyte. A single dynamic object (the main 296 program, any shared library) is limited to 4GB in size and I want to see 297 the program that manages to have a symbol table of more than 2 GB with a 298 total size of at max 4 GB. */ 299 300#define PLT_ENTRY_WORD0 (bfd_vma) 0xc0100000 301#define PLT_ENTRY_WORD1 (bfd_vma) 0x0000e310 302#define PLT_ENTRY_WORD2 (bfd_vma) 0x10000004 303#define PLT_ENTRY_WORD3 (bfd_vma) 0x07f10d10 304#define PLT_ENTRY_WORD4 (bfd_vma) 0xe310100c 305#define PLT_ENTRY_WORD5 (bfd_vma) 0x0014c0f4 306#define PLT_ENTRY_WORD6 (bfd_vma) 0x00000000 307#define PLT_ENTRY_WORD7 (bfd_vma) 0x00000000 308 309/* The first PLT entry pushes the offset into the symbol table 310 from R1 onto the stack at 8(15) and the loader object info 311 at 12(15), loads the loader address in R1 and jumps to it. */ 312 313/* The first entry in the PLT: 314 315 PLT0: 316 STG 1,56(15) # r1 contains the offset into the symbol table 317 LARL 1,_GLOBAL_OFFSET_TABLE # load address of global offset table 318 MVC 48(8,15),8(1) # move loader ino (object struct address) to stack 319 LG 1,16(1) # get entry address of loader 320 BCR 15,1 # jump to loader 321 322 Fixup at offset 8: relative address to start of GOT. */ 323 324#define PLT_FIRST_ENTRY_WORD0 (bfd_vma) 0xe310f038 325#define PLT_FIRST_ENTRY_WORD1 (bfd_vma) 0x0024c010 326#define PLT_FIRST_ENTRY_WORD2 (bfd_vma) 0x00000000 327#define PLT_FIRST_ENTRY_WORD3 (bfd_vma) 0xd207f030 328#define PLT_FIRST_ENTRY_WORD4 (bfd_vma) 0x1008e310 329#define PLT_FIRST_ENTRY_WORD5 (bfd_vma) 0x10100004 330#define PLT_FIRST_ENTRY_WORD6 (bfd_vma) 0x07f10700 331#define PLT_FIRST_ENTRY_WORD7 (bfd_vma) 0x07000700 332 333/* The s390 linker needs to keep track of the number of relocs that it 334 decides to copy as dynamic relocs in check_relocs for each symbol. 335 This is so that it can later discard them if they are found to be 336 unnecessary. We store the information in a field extending the 337 regular ELF linker hash table. */ 338 339struct elf_s390_dyn_relocs 340{ 341 struct elf_s390_dyn_relocs *next; 342 343 /* The input section of the reloc. */ 344 asection *sec; 345 346 /* Total number of relocs copied for the input section. */ 347 bfd_size_type count; 348 349 /* Number of pc-relative relocs copied for the input section. */ 350 bfd_size_type pc_count; 351}; 352 353/* s390 ELF linker hash entry. */ 354 355struct elf_s390_link_hash_entry 356{ 357 struct elf_link_hash_entry elf; 358 359 /* Track dynamic relocs copied for this symbol. */ 360 struct elf_s390_dyn_relocs *dyn_relocs; 361}; 362 363/* s390 ELF linker hash table. */ 364 365struct elf_s390_link_hash_table 366{ 367 struct elf_link_hash_table elf; 368 369 /* Short-cuts to get to dynamic linker sections. */ 370 asection *sgot; 371 asection *sgotplt; 372 asection *srelgot; 373 asection *splt; 374 asection *srelplt; 375 asection *sdynbss; 376 asection *srelbss; 377 378 /* Small local sym to section mapping cache. */ 379 struct sym_sec_cache sym_sec; 380}; 381 382/* Get the s390 ELF linker hash table from a link_info structure. */ 383 384#define elf_s390_hash_table(p) \ 385 ((struct elf_s390_link_hash_table *) ((p)->hash)) 386 387/* Create an entry in an s390 ELF linker hash table. */ 388 389static struct bfd_hash_entry * 390link_hash_newfunc (entry, table, string) 391 struct bfd_hash_entry *entry; 392 struct bfd_hash_table *table; 393 const char *string; 394{ 395 /* Allocate the structure if it has not already been allocated by a 396 subclass. */ 397 if (entry == NULL) 398 { 399 entry = bfd_hash_allocate (table, 400 sizeof (struct elf_s390_link_hash_entry)); 401 if (entry == NULL) 402 return entry; 403 } 404 405 /* Call the allocation method of the superclass. */ 406 entry = _bfd_elf_link_hash_newfunc (entry, table, string); 407 if (entry != NULL) 408 { 409 struct elf_s390_link_hash_entry *eh; 410 411 eh = (struct elf_s390_link_hash_entry *) entry; 412 eh->dyn_relocs = NULL; 413 } 414 415 return entry; 416} 417 418/* Create an s390 ELF linker hash table. */ 419 420static struct bfd_link_hash_table * 421elf_s390_link_hash_table_create (abfd) 422 bfd *abfd; 423{ 424 struct elf_s390_link_hash_table *ret; 425 bfd_size_type amt = sizeof (struct elf_s390_link_hash_table); 426 427 ret = (struct elf_s390_link_hash_table *) bfd_alloc (abfd, amt); 428 if (ret == NULL) 429 return NULL; 430 431 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc)) 432 { 433 bfd_release (abfd, ret); 434 return NULL; 435 } 436 437 ret->sgot = NULL; 438 ret->sgotplt = NULL; 439 ret->srelgot = NULL; 440 ret->splt = NULL; 441 ret->srelplt = NULL; 442 ret->sdynbss = NULL; 443 ret->srelbss = NULL; 444 ret->sym_sec.abfd = NULL; 445 446 return &ret->elf.root; 447} 448 449/* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up 450 shortcuts to them in our hash table. */ 451 452static boolean 453create_got_section (dynobj, info) 454 bfd *dynobj; 455 struct bfd_link_info *info; 456{ 457 struct elf_s390_link_hash_table *htab; 458 459 if (! _bfd_elf_create_got_section (dynobj, info)) 460 return false; 461 462 htab = elf_s390_hash_table (info); 463 htab->sgot = bfd_get_section_by_name (dynobj, ".got"); 464 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt"); 465 if (!htab->sgot || !htab->sgotplt) 466 abort (); 467 468 htab->srelgot = bfd_make_section (dynobj, ".rela.got"); 469 if (htab->srelgot == NULL 470 || ! bfd_set_section_flags (dynobj, htab->srelgot, 471 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS 472 | SEC_IN_MEMORY | SEC_LINKER_CREATED 473 | SEC_READONLY)) 474 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2)) 475 return false; 476 return true; 477} 478 479/* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and 480 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our 481 hash table. */ 482 483static boolean 484elf_s390_create_dynamic_sections (dynobj, info) 485 bfd *dynobj; 486 struct bfd_link_info *info; 487{ 488 struct elf_s390_link_hash_table *htab; 489 490 htab = elf_s390_hash_table (info); 491 if (!htab->sgot && !create_got_section (dynobj, info)) 492 return false; 493 494 if (!_bfd_elf_create_dynamic_sections (dynobj, info)) 495 return false; 496 497 htab->splt = bfd_get_section_by_name (dynobj, ".plt"); 498 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt"); 499 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss"); 500 if (!info->shared) 501 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss"); 502 503 if (!htab->splt || !htab->srelplt || !htab->sdynbss 504 || (!info->shared && !htab->srelbss)) 505 abort (); 506 507 return true; 508} 509 510/* Copy the extra info we tack onto an elf_link_hash_entry. */ 511 512static void 513elf_s390_copy_indirect_symbol (dir, ind) 514 struct elf_link_hash_entry *dir, *ind; 515{ 516 struct elf_s390_link_hash_entry *edir, *eind; 517 518 edir = (struct elf_s390_link_hash_entry *) dir; 519 eind = (struct elf_s390_link_hash_entry *) ind; 520 521 if (eind->dyn_relocs != NULL) 522 { 523 if (edir->dyn_relocs != NULL) 524 { 525 struct elf_s390_dyn_relocs **pp; 526 struct elf_s390_dyn_relocs *p; 527 528 if (ind->root.type == bfd_link_hash_indirect) 529 abort (); 530 531 /* Add reloc counts against the weak sym to the strong sym 532 list. Merge any entries against the same section. */ 533 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; ) 534 { 535 struct elf_s390_dyn_relocs *q; 536 537 for (q = edir->dyn_relocs; q != NULL; q = q->next) 538 if (q->sec == p->sec) 539 { 540 q->pc_count += p->pc_count; 541 q->count += p->count; 542 *pp = p->next; 543 break; 544 } 545 if (q == NULL) 546 pp = &p->next; 547 } 548 *pp = edir->dyn_relocs; 549 } 550 551 edir->dyn_relocs = eind->dyn_relocs; 552 eind->dyn_relocs = NULL; 553 } 554 555 _bfd_elf_link_hash_copy_indirect (dir, ind); 556} 557 558/* Look through the relocs for a section during the first phase, and 559 allocate space in the global offset table or procedure linkage 560 table. */ 561 562static boolean 563elf_s390_check_relocs (abfd, info, sec, relocs) 564 bfd *abfd; 565 struct bfd_link_info *info; 566 asection *sec; 567 const Elf_Internal_Rela *relocs; 568{ 569 struct elf_s390_link_hash_table *htab; 570 Elf_Internal_Shdr *symtab_hdr; 571 struct elf_link_hash_entry **sym_hashes; 572 const Elf_Internal_Rela *rel; 573 const Elf_Internal_Rela *rel_end; 574 asection *sreloc; 575 576 if (info->relocateable) 577 return true; 578 579 htab = elf_s390_hash_table (info); 580 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 581 sym_hashes = elf_sym_hashes (abfd); 582 583 sreloc = NULL; 584 585 rel_end = relocs + sec->reloc_count; 586 for (rel = relocs; rel < rel_end; rel++) 587 { 588 unsigned long r_symndx; 589 struct elf_link_hash_entry *h; 590 591 r_symndx = ELF64_R_SYM (rel->r_info); 592 593 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr)) 594 { 595 (*_bfd_error_handler) (_("%s: bad symbol index: %d"), 596 bfd_archive_filename (abfd), 597 r_symndx); 598 return false; 599 } 600 601 if (r_symndx < symtab_hdr->sh_info) 602 h = NULL; 603 else 604 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 605 606 switch (ELF64_R_TYPE (rel->r_info)) 607 { 608 case R_390_GOT12: 609 case R_390_GOT16: 610 case R_390_GOT32: 611 case R_390_GOT64: 612 case R_390_GOTENT: 613 /* This symbol requires a global offset table entry. */ 614 if (h != NULL) 615 { 616 h->got.refcount += 1; 617 } 618 else 619 { 620 bfd_signed_vma *local_got_refcounts; 621 622 /* This is a global offset table entry for a local symbol. */ 623 local_got_refcounts = elf_local_got_refcounts (abfd); 624 if (local_got_refcounts == NULL) 625 { 626 bfd_size_type size; 627 628 size = symtab_hdr->sh_info; 629 size *= sizeof (bfd_signed_vma); 630 local_got_refcounts = ((bfd_signed_vma *) 631 bfd_zalloc (abfd, size)); 632 if (local_got_refcounts == NULL) 633 return false; 634 elf_local_got_refcounts (abfd) = local_got_refcounts; 635 } 636 local_got_refcounts[r_symndx] += 1; 637 } 638 /* Fall through */ 639 640 case R_390_GOTOFF: 641 case R_390_GOTPC: 642 case R_390_GOTPCDBL: 643 if (htab->sgot == NULL) 644 { 645 if (htab->elf.dynobj == NULL) 646 htab->elf.dynobj = abfd; 647 if (!create_got_section (htab->elf.dynobj, info)) 648 return false; 649 } 650 break; 651 652 case R_390_PLT16DBL: 653 case R_390_PLT32: 654 case R_390_PLT32DBL: 655 case R_390_PLT64: 656 /* This symbol requires a procedure linkage table entry. We 657 actually build the entry in adjust_dynamic_symbol, 658 because this might be a case of linking PIC code which is 659 never referenced by a dynamic object, in which case we 660 don't need to generate a procedure linkage table entry 661 after all. */ 662 663 /* If this is a local symbol, we resolve it directly without 664 creating a procedure linkage table entry. */ 665 if (h == NULL) 666 continue; 667 668 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT; 669 h->plt.refcount += 1; 670 break; 671 672 case R_390_8: 673 case R_390_16: 674 case R_390_32: 675 case R_390_64: 676 case R_390_PC16: 677 case R_390_PC16DBL: 678 case R_390_PC32: 679 case R_390_PC32DBL: 680 case R_390_PC64: 681 if (h != NULL && !info->shared) 682 { 683 /* If this reloc is in a read-only section, we might 684 need a copy reloc. We can't check reliably at this 685 stage whether the section is read-only, as input 686 sections have not yet been mapped to output sections. 687 Tentatively set the flag for now, and correct in 688 adjust_dynamic_symbol. */ 689 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF; 690 691 /* We may need a .plt entry if the function this reloc 692 refers to is in a shared lib. */ 693 h->plt.refcount += 1; 694 } 695 696 /* If we are creating a shared library, and this is a reloc 697 against a global symbol, or a non PC relative reloc 698 against a local symbol, then we need to copy the reloc 699 into the shared library. However, if we are linking with 700 -Bsymbolic, we do not need to copy a reloc against a 701 global symbol which is defined in an object we are 702 including in the link (i.e., DEF_REGULAR is set). At 703 this point we have not seen all the input files, so it is 704 possible that DEF_REGULAR is not set now but will be set 705 later (it is never cleared). In case of a weak definition, 706 DEF_REGULAR may be cleared later by a strong definition in 707 a shared library. We account for that possibility below by 708 storing information in the relocs_copied field of the hash 709 table entry. A similar situation occurs when creating 710 shared libraries and symbol visibility changes render the 711 symbol local. 712 713 If on the other hand, we are creating an executable, we 714 may need to keep relocations for symbols satisfied by a 715 dynamic library if we manage to avoid copy relocs for the 716 symbol. */ 717 if ((info->shared 718 && (sec->flags & SEC_ALLOC) != 0 719 && ((ELF64_R_TYPE (rel->r_info) != R_390_PC16 720 && ELF64_R_TYPE (rel->r_info) != R_390_PC16DBL 721 && ELF64_R_TYPE (rel->r_info) != R_390_PC32 722 && ELF64_R_TYPE (rel->r_info) != R_390_PC32DBL 723 && ELF64_R_TYPE (rel->r_info) != R_390_PC64) 724 || (h != NULL 725 && (! info->symbolic 726 || h->root.type == bfd_link_hash_defweak 727 || (h->elf_link_hash_flags 728 & ELF_LINK_HASH_DEF_REGULAR) == 0)))) 729 || (!info->shared 730 && (sec->flags & SEC_ALLOC) != 0 731 && h != NULL 732 && (h->root.type == bfd_link_hash_defweak 733 || (h->elf_link_hash_flags 734 & ELF_LINK_HASH_DEF_REGULAR) == 0))) 735 { 736 struct elf_s390_dyn_relocs *p; 737 struct elf_s390_dyn_relocs **head; 738 739 /* We must copy these reloc types into the output file. 740 Create a reloc section in dynobj and make room for 741 this reloc. */ 742 if (sreloc == NULL) 743 { 744 const char *name; 745 bfd *dynobj; 746 747 name = (bfd_elf_string_from_elf_section 748 (abfd, 749 elf_elfheader (abfd)->e_shstrndx, 750 elf_section_data (sec)->rel_hdr.sh_name)); 751 if (name == NULL) 752 return false; 753 754 if (strncmp (name, ".rela", 5) != 0 755 || strcmp (bfd_get_section_name (abfd, sec), 756 name + 5) != 0) 757 { 758 (*_bfd_error_handler) 759 (_("%s: bad relocation section name `%s\'"), 760 bfd_archive_filename (abfd), name); 761 } 762 763 if (htab->elf.dynobj == NULL) 764 htab->elf.dynobj = abfd; 765 766 dynobj = htab->elf.dynobj; 767 sreloc = bfd_get_section_by_name (dynobj, name); 768 if (sreloc == NULL) 769 { 770 flagword flags; 771 772 sreloc = bfd_make_section (dynobj, name); 773 flags = (SEC_HAS_CONTENTS | SEC_READONLY 774 | SEC_IN_MEMORY | SEC_LINKER_CREATED); 775 if ((sec->flags & SEC_ALLOC) != 0) 776 flags |= SEC_ALLOC | SEC_LOAD; 777 if (sreloc == NULL 778 || ! bfd_set_section_flags (dynobj, sreloc, flags) 779 || ! bfd_set_section_alignment (dynobj, sreloc, 2)) 780 return false; 781 } 782 elf_section_data (sec)->sreloc = sreloc; 783 } 784 785 /* If this is a global symbol, we count the number of 786 relocations we need for this symbol. */ 787 if (h != NULL) 788 { 789 head = &((struct elf_s390_link_hash_entry *) h)->dyn_relocs; 790 } 791 else 792 { 793 /* Track dynamic relocs needed for local syms too. 794 We really need local syms available to do this 795 easily. Oh well. */ 796 797 asection *s; 798 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec, 799 sec, r_symndx); 800 if (s == NULL) 801 return false; 802 803 head = ((struct elf_s390_dyn_relocs **) 804 &elf_section_data (s)->local_dynrel); 805 } 806 807 p = *head; 808 if (p == NULL || p->sec != sec) 809 { 810 bfd_size_type amt = sizeof *p; 811 p = ((struct elf_s390_dyn_relocs *) 812 bfd_alloc (htab->elf.dynobj, amt)); 813 if (p == NULL) 814 return false; 815 p->next = *head; 816 *head = p; 817 p->sec = sec; 818 p->count = 0; 819 p->pc_count = 0; 820 } 821 822 p->count += 1; 823 if (ELF64_R_TYPE (rel->r_info) == R_390_PC16 824 || ELF64_R_TYPE (rel->r_info) == R_390_PC16DBL 825 || ELF64_R_TYPE (rel->r_info) == R_390_PC32 826 || ELF64_R_TYPE (rel->r_info) == R_390_PC32DBL 827 || ELF64_R_TYPE (rel->r_info) == R_390_PC64) 828 p->pc_count += 1; 829 } 830 break; 831 832 /* This relocation describes the C++ object vtable hierarchy. 833 Reconstruct it for later use during GC. */ 834 case R_390_GNU_VTINHERIT: 835 if (!_bfd_elf64_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 836 return false; 837 break; 838 839 /* This relocation describes which C++ vtable entries are actually 840 used. Record for later use during GC. */ 841 case R_390_GNU_VTENTRY: 842 if (!_bfd_elf64_gc_record_vtentry (abfd, sec, h, rel->r_addend)) 843 return false; 844 break; 845 846 default: 847 break; 848 } 849 } 850 851 return true; 852} 853 854/* Return the section that should be marked against GC for a given 855 relocation. */ 856 857static asection * 858elf_s390_gc_mark_hook (abfd, info, rel, h, sym) 859 bfd *abfd; 860 struct bfd_link_info *info ATTRIBUTE_UNUSED; 861 Elf_Internal_Rela *rel; 862 struct elf_link_hash_entry *h; 863 Elf_Internal_Sym *sym; 864{ 865 if (h != NULL) 866 { 867 switch (ELF64_R_TYPE (rel->r_info)) 868 { 869 case R_390_GNU_VTINHERIT: 870 case R_390_GNU_VTENTRY: 871 break; 872 873 default: 874 switch (h->root.type) 875 { 876 case bfd_link_hash_defined: 877 case bfd_link_hash_defweak: 878 return h->root.u.def.section; 879 880 case bfd_link_hash_common: 881 return h->root.u.c.p->section; 882 883 default: 884 break; 885 } 886 } 887 } 888 else 889 { 890 return bfd_section_from_elf_index (abfd, sym->st_shndx); 891 } 892 893 return NULL; 894} 895 896/* Update the got entry reference counts for the section being removed. */ 897 898static boolean 899elf_s390_gc_sweep_hook (abfd, info, sec, relocs) 900 bfd *abfd; 901 struct bfd_link_info *info; 902 asection *sec; 903 const Elf_Internal_Rela *relocs; 904{ 905 Elf_Internal_Shdr *symtab_hdr; 906 struct elf_link_hash_entry **sym_hashes; 907 bfd_signed_vma *local_got_refcounts; 908 const Elf_Internal_Rela *rel, *relend; 909 unsigned long r_symndx; 910 struct elf_link_hash_entry *h; 911 912 elf_section_data (sec)->local_dynrel = NULL; 913 914 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 915 sym_hashes = elf_sym_hashes (abfd); 916 local_got_refcounts = elf_local_got_refcounts (abfd); 917 918 relend = relocs + sec->reloc_count; 919 for (rel = relocs; rel < relend; rel++) 920 switch (ELF64_R_TYPE (rel->r_info)) 921 { 922 case R_390_GOT12: 923 case R_390_GOT16: 924 case R_390_GOT32: 925 case R_390_GOT64: 926 case R_390_GOTOFF: 927 case R_390_GOTPC: 928 case R_390_GOTPCDBL: 929 case R_390_GOTENT: 930 r_symndx = ELF64_R_SYM (rel->r_info); 931 if (r_symndx >= symtab_hdr->sh_info) 932 { 933 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 934 if (h->got.refcount > 0) 935 h->got.refcount -= 1; 936 } 937 else if (local_got_refcounts != NULL) 938 { 939 if (local_got_refcounts[r_symndx] > 0) 940 local_got_refcounts[r_symndx] -= 1; 941 } 942 break; 943 944 case R_390_8: 945 case R_390_12: 946 case R_390_16: 947 case R_390_32: 948 case R_390_64: 949 case R_390_PC16: 950 case R_390_PC16DBL: 951 case R_390_PC32: 952 case R_390_PC32DBL: 953 case R_390_PC64: 954 r_symndx = ELF64_R_SYM (rel->r_info); 955 if (r_symndx >= symtab_hdr->sh_info) 956 { 957 struct elf_s390_link_hash_entry *eh; 958 struct elf_s390_dyn_relocs **pp; 959 struct elf_s390_dyn_relocs *p; 960 961 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 962 963 if (!info->shared && h->plt.refcount > 0) 964 h->plt.refcount -= 1; 965 966 eh = (struct elf_s390_link_hash_entry *) h; 967 968 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next) 969 if (p->sec == sec) 970 { 971 if (ELF64_R_TYPE (rel->r_info) == R_390_PC16 972 || ELF64_R_TYPE (rel->r_info) == R_390_PC16DBL 973 || ELF64_R_TYPE (rel->r_info) == R_390_PC32) 974 p->pc_count -= 1; 975 p->count -= 1; 976 if (p->count == 0) 977 *pp = p->next; 978 break; 979 } 980 } 981 break; 982 983 case R_390_PLT16DBL: 984 case R_390_PLT32: 985 case R_390_PLT32DBL: 986 case R_390_PLT64: 987 r_symndx = ELF64_R_SYM (rel->r_info); 988 if (r_symndx >= symtab_hdr->sh_info) 989 { 990 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 991 if (h->plt.refcount > 0) 992 h->plt.refcount -= 1; 993 } 994 break; 995 996 default: 997 break; 998 } 999 1000 return true; 1001} 1002 1003/* Adjust a symbol defined by a dynamic object and referenced by a 1004 regular object. The current definition is in some section of the 1005 dynamic object, but we're not including those sections. We have to 1006 change the definition to something the rest of the link can 1007 understand. */ 1008 1009static boolean 1010elf_s390_adjust_dynamic_symbol (info, h) 1011 struct bfd_link_info *info; 1012 struct elf_link_hash_entry *h; 1013{ 1014 struct elf_s390_link_hash_table *htab; 1015 struct elf_s390_link_hash_entry * eh; 1016 struct elf_s390_dyn_relocs *p; 1017 asection *s; 1018 unsigned int power_of_two; 1019 1020 /* If this is a function, put it in the procedure linkage table. We 1021 will fill in the contents of the procedure linkage table later 1022 (although we could actually do it here). */ 1023 if (h->type == STT_FUNC 1024 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0) 1025 { 1026 if (h->plt.refcount <= 0 1027 || (! info->shared 1028 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0 1029 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0 1030 && h->root.type != bfd_link_hash_undefweak 1031 && h->root.type != bfd_link_hash_undefined)) 1032 { 1033 /* This case can occur if we saw a PLT32 reloc in an input 1034 file, but the symbol was never referred to by a dynamic 1035 object, or if all references were garbage collected. In 1036 such a case, we don't actually need to build a procedure 1037 linkage table, and we can just do a PC32 reloc instead. */ 1038 h->plt.offset = (bfd_vma) -1; 1039 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT; 1040 } 1041 1042 return true; 1043 } 1044 else 1045 /* It's possible that we incorrectly decided a .plt reloc was 1046 needed for an R_390_PC32 reloc to a non-function sym in 1047 check_relocs. We can't decide accurately between function and 1048 non-function syms in check-relocs; Objects loaded later in 1049 the link may change h->type. So fix it now. */ 1050 h->plt.offset = (bfd_vma) -1; 1051 1052 /* If this is a weak symbol, and there is a real definition, the 1053 processor independent code will have arranged for us to see the 1054 real definition first, and we can just use the same value. */ 1055 if (h->weakdef != NULL) 1056 { 1057 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined 1058 || h->weakdef->root.type == bfd_link_hash_defweak); 1059 h->root.u.def.section = h->weakdef->root.u.def.section; 1060 h->root.u.def.value = h->weakdef->root.u.def.value; 1061 return true; 1062 } 1063 1064 /* This is a reference to a symbol defined by a dynamic object which 1065 is not a function. */ 1066 1067 /* If we are creating a shared library, we must presume that the 1068 only references to the symbol are via the global offset table. 1069 For such cases we need not do anything here; the relocations will 1070 be handled correctly by relocate_section. */ 1071 if (info->shared) 1072 return true; 1073 1074 /* If there are no references to this symbol that do not use the 1075 GOT, we don't need to generate a copy reloc. */ 1076 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0) 1077 return true; 1078 1079 /* If -z nocopyreloc was given, we won't generate them either. */ 1080 if (info->nocopyreloc) 1081 { 1082 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF; 1083 return true; 1084 } 1085 1086 eh = (struct elf_s390_link_hash_entry *) h; 1087 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1088 { 1089 s = p->sec->output_section; 1090 if (s != NULL && (s->flags & SEC_READONLY) != 0) 1091 break; 1092 } 1093 1094 /* If we didn't find any dynamic relocs in read-only sections, then 1095 we'll be keeping the dynamic relocs and avoiding the copy reloc. */ 1096 if (p == NULL) 1097 { 1098 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF; 1099 return true; 1100 } 1101 1102 /* We must allocate the symbol in our .dynbss section, which will 1103 become part of the .bss section of the executable. There will be 1104 an entry for this symbol in the .dynsym section. The dynamic 1105 object will contain position independent code, so all references 1106 from the dynamic object to this symbol will go through the global 1107 offset table. The dynamic linker will use the .dynsym entry to 1108 determine the address it must put in the global offset table, so 1109 both the dynamic object and the regular object will refer to the 1110 same memory location for the variable. */ 1111 1112 htab = elf_s390_hash_table (info); 1113 1114 /* We must generate a R_390_COPY reloc to tell the dynamic linker to 1115 copy the initial value out of the dynamic object and into the 1116 runtime process image. */ 1117 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0) 1118 { 1119 htab->srelbss->_raw_size += sizeof (Elf64_External_Rela); 1120 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY; 1121 } 1122 1123 /* We need to figure out the alignment required for this symbol. I 1124 have no idea how ELF linkers handle this. */ 1125 power_of_two = bfd_log2 (h->size); 1126 if (power_of_two > 3) 1127 power_of_two = 3; 1128 1129 /* Apply the required alignment. */ 1130 s = htab->sdynbss; 1131 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two)); 1132 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s)) 1133 { 1134 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two)) 1135 return false; 1136 } 1137 1138 /* Define the symbol as being at this point in the section. */ 1139 h->root.u.def.section = s; 1140 h->root.u.def.value = s->_raw_size; 1141 1142 /* Increment the section size to make room for the symbol. */ 1143 s->_raw_size += h->size; 1144 1145 return true; 1146} 1147 1148/* This is the condition under which elf_s390_finish_dynamic_symbol 1149 will be called from elflink.h. If elflink.h doesn't call our 1150 finish_dynamic_symbol routine, we'll need to do something about 1151 initializing any .plt and .got entries in elf_s390_relocate_section. */ 1152#define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, INFO, H) \ 1153 ((DYN) \ 1154 && ((INFO)->shared \ 1155 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \ 1156 && ((H)->dynindx != -1 \ 1157 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)) 1158 1159/* Allocate space in .plt, .got and associated reloc sections for 1160 dynamic relocs. */ 1161 1162static boolean 1163allocate_dynrelocs (h, inf) 1164 struct elf_link_hash_entry *h; 1165 PTR inf; 1166{ 1167 struct bfd_link_info *info; 1168 struct elf_s390_link_hash_table *htab; 1169 struct elf_s390_link_hash_entry *eh; 1170 struct elf_s390_dyn_relocs *p; 1171 1172 if (h->root.type == bfd_link_hash_indirect) 1173 return true; 1174 1175 if (h->root.type == bfd_link_hash_warning) 1176 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1177 1178 info = (struct bfd_link_info *) inf; 1179 htab = elf_s390_hash_table (info); 1180 1181 if (htab->elf.dynamic_sections_created 1182 && h->plt.refcount > 0) 1183 { 1184 /* Make sure this symbol is output as a dynamic symbol. 1185 Undefined weak syms won't yet be marked as dynamic. */ 1186 if (h->dynindx == -1 1187 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) 1188 { 1189 if (! bfd_elf64_link_record_dynamic_symbol (info, h)) 1190 return false; 1191 } 1192 1193 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h)) 1194 { 1195 asection *s = htab->splt; 1196 1197 /* If this is the first .plt entry, make room for the special 1198 first entry. */ 1199 if (s->_raw_size == 0) 1200 s->_raw_size += PLT_FIRST_ENTRY_SIZE; 1201 1202 h->plt.offset = s->_raw_size; 1203 1204 /* If this symbol is not defined in a regular file, and we are 1205 not generating a shared library, then set the symbol to this 1206 location in the .plt. This is required to make function 1207 pointers compare as equal between the normal executable and 1208 the shared library. */ 1209 if (! info->shared 1210 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) 1211 { 1212 h->root.u.def.section = s; 1213 h->root.u.def.value = h->plt.offset; 1214 } 1215 1216 /* Make room for this entry. */ 1217 s->_raw_size += PLT_ENTRY_SIZE; 1218 1219 /* We also need to make an entry in the .got.plt section, which 1220 will be placed in the .got section by the linker script. */ 1221 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE; 1222 1223 /* We also need to make an entry in the .rela.plt section. */ 1224 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela); 1225 } 1226 else 1227 { 1228 h->plt.offset = (bfd_vma) -1; 1229 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT; 1230 } 1231 } 1232 else 1233 { 1234 h->plt.offset = (bfd_vma) -1; 1235 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT; 1236 } 1237 1238 if (h->got.refcount > 0) 1239 { 1240 asection *s; 1241 boolean dyn; 1242 1243 /* Make sure this symbol is output as a dynamic symbol. 1244 Undefined weak syms won't yet be marked as dynamic. */ 1245 if (h->dynindx == -1 1246 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) 1247 { 1248 if (! bfd_elf64_link_record_dynamic_symbol (info, h)) 1249 return false; 1250 } 1251 1252 s = htab->sgot; 1253 h->got.offset = s->_raw_size; 1254 s->_raw_size += GOT_ENTRY_SIZE; 1255 dyn = htab->elf.dynamic_sections_created; 1256 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)) 1257 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela); 1258 } 1259 else 1260 h->got.offset = (bfd_vma) -1; 1261 1262 eh = (struct elf_s390_link_hash_entry *) h; 1263 if (eh->dyn_relocs == NULL) 1264 return true; 1265 1266 /* In the shared -Bsymbolic case, discard space allocated for 1267 dynamic pc-relative relocs against symbols which turn out to be 1268 defined in regular objects. For the normal shared case, discard 1269 space for pc-relative relocs that have become local due to symbol 1270 visibility changes. */ 1271 1272 if (info->shared) 1273 { 1274 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0 1275 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0 1276 || info->symbolic)) 1277 { 1278 struct elf_s390_dyn_relocs **pp; 1279 1280 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 1281 { 1282 p->count -= p->pc_count; 1283 p->pc_count = 0; 1284 if (p->count == 0) 1285 *pp = p->next; 1286 else 1287 pp = &p->next; 1288 } 1289 } 1290 } 1291 else 1292 { 1293 /* For the non-shared case, discard space for relocs against 1294 symbols which turn out to need copy relocs or are not 1295 dynamic. */ 1296 1297 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0 1298 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 1299 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) 1300 || (htab->elf.dynamic_sections_created 1301 && (h->root.type == bfd_link_hash_undefweak 1302 || h->root.type == bfd_link_hash_undefined)))) 1303 { 1304 /* Make sure this symbol is output as a dynamic symbol. 1305 Undefined weak syms won't yet be marked as dynamic. */ 1306 if (h->dynindx == -1 1307 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) 1308 { 1309 if (! bfd_elf64_link_record_dynamic_symbol (info, h)) 1310 return false; 1311 } 1312 1313 /* If that succeeded, we know we'll be keeping all the 1314 relocs. */ 1315 if (h->dynindx != -1) 1316 goto keep; 1317 } 1318 1319 eh->dyn_relocs = NULL; 1320 1321 keep: ; 1322 } 1323 1324 /* Finally, allocate space. */ 1325 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1326 { 1327 asection *sreloc = elf_section_data (p->sec)->sreloc; 1328 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela); 1329 } 1330 1331 return true; 1332} 1333 1334/* Find any dynamic relocs that apply to read-only sections. */ 1335 1336static boolean 1337readonly_dynrelocs (h, inf) 1338 struct elf_link_hash_entry *h; 1339 PTR inf; 1340{ 1341 struct elf_s390_link_hash_entry *eh; 1342 struct elf_s390_dyn_relocs *p; 1343 1344 if (h->root.type == bfd_link_hash_warning) 1345 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1346 1347 eh = (struct elf_s390_link_hash_entry *) h; 1348 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1349 { 1350 asection *s = p->sec->output_section; 1351 1352 if (s != NULL && (s->flags & SEC_READONLY) != 0) 1353 { 1354 struct bfd_link_info *info = (struct bfd_link_info *) inf; 1355 1356 info->flags |= DF_TEXTREL; 1357 1358 /* Not an error, just cut short the traversal. */ 1359 return false; 1360 } 1361 } 1362 return true; 1363} 1364 1365/* Set the sizes of the dynamic sections. */ 1366 1367static boolean 1368elf_s390_size_dynamic_sections (output_bfd, info) 1369 bfd *output_bfd ATTRIBUTE_UNUSED; 1370 struct bfd_link_info *info; 1371{ 1372 struct elf_s390_link_hash_table *htab; 1373 bfd *dynobj; 1374 asection *s; 1375 boolean relocs; 1376 bfd *ibfd; 1377 1378 htab = elf_s390_hash_table (info); 1379 dynobj = htab->elf.dynobj; 1380 if (dynobj == NULL) 1381 abort (); 1382 1383 if (htab->elf.dynamic_sections_created) 1384 { 1385 /* Set the contents of the .interp section to the interpreter. */ 1386 if (! info->shared) 1387 { 1388 s = bfd_get_section_by_name (dynobj, ".interp"); 1389 if (s == NULL) 1390 abort (); 1391 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER; 1392 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER; 1393 } 1394 } 1395 1396 /* Set up .got offsets for local syms, and space for local dynamic 1397 relocs. */ 1398 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next) 1399 { 1400 bfd_signed_vma *local_got; 1401 bfd_signed_vma *end_local_got; 1402 bfd_size_type locsymcount; 1403 Elf_Internal_Shdr *symtab_hdr; 1404 asection *srela; 1405 1406 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour) 1407 continue; 1408 1409 for (s = ibfd->sections; s != NULL; s = s->next) 1410 { 1411 struct elf_s390_dyn_relocs *p; 1412 1413 for (p = *((struct elf_s390_dyn_relocs **) 1414 &elf_section_data (s)->local_dynrel); 1415 p != NULL; 1416 p = p->next) 1417 { 1418 if (!bfd_is_abs_section (p->sec) 1419 && bfd_is_abs_section (p->sec->output_section)) 1420 { 1421 /* Input section has been discarded, either because 1422 it is a copy of a linkonce section or due to 1423 linker script /DISCARD/, so we'll be discarding 1424 the relocs too. */ 1425 } 1426 else if (p->count != 0) 1427 { 1428 srela = elf_section_data (p->sec)->sreloc; 1429 srela->_raw_size += p->count * sizeof (Elf64_External_Rela); 1430 if ((p->sec->output_section->flags & SEC_READONLY) != 0) 1431 info->flags |= DF_TEXTREL; 1432 } 1433 } 1434 } 1435 1436 local_got = elf_local_got_refcounts (ibfd); 1437 if (!local_got) 1438 continue; 1439 1440 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr; 1441 locsymcount = symtab_hdr->sh_info; 1442 end_local_got = local_got + locsymcount; 1443 s = htab->sgot; 1444 srela = htab->srelgot; 1445 for (; local_got < end_local_got; ++local_got) 1446 { 1447 if (*local_got > 0) 1448 { 1449 *local_got = s->_raw_size; 1450 s->_raw_size += GOT_ENTRY_SIZE; 1451 if (info->shared) 1452 srela->_raw_size += sizeof (Elf64_External_Rela); 1453 } 1454 else 1455 *local_got = (bfd_vma) -1; 1456 } 1457 } 1458 1459 /* Allocate global sym .plt and .got entries, and space for global 1460 sym dynamic relocs. */ 1461 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info); 1462 1463 /* We now have determined the sizes of the various dynamic sections. 1464 Allocate memory for them. */ 1465 relocs = false; 1466 for (s = dynobj->sections; s != NULL; s = s->next) 1467 { 1468 if ((s->flags & SEC_LINKER_CREATED) == 0) 1469 continue; 1470 1471 if (s == htab->splt 1472 || s == htab->sgot 1473 || s == htab->sgotplt) 1474 { 1475 /* Strip this section if we don't need it; see the 1476 comment below. */ 1477 } 1478 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0) 1479 { 1480 if (s->_raw_size != 0 && s != htab->srelplt) 1481 relocs = true; 1482 1483 /* We use the reloc_count field as a counter if we need 1484 to copy relocs into the output file. */ 1485 s->reloc_count = 0; 1486 } 1487 else 1488 { 1489 /* It's not one of our sections, so don't allocate space. */ 1490 continue; 1491 } 1492 1493 if (s->_raw_size == 0) 1494 { 1495 /* If we don't need this section, strip it from the 1496 output file. This is to handle .rela.bss and 1497 .rela.plt. We must create it in 1498 create_dynamic_sections, because it must be created 1499 before the linker maps input sections to output 1500 sections. The linker does that before 1501 adjust_dynamic_symbol is called, and it is that 1502 function which decides whether anything needs to go 1503 into these sections. */ 1504 1505 _bfd_strip_section_from_output (info, s); 1506 continue; 1507 } 1508 1509 /* Allocate memory for the section contents. We use bfd_zalloc 1510 here in case unused entries are not reclaimed before the 1511 section's contents are written out. This should not happen, 1512 but this way if it does, we get a R_390_NONE reloc instead 1513 of garbage. */ 1514 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size); 1515 if (s->contents == NULL) 1516 return false; 1517 } 1518 1519 if (htab->elf.dynamic_sections_created) 1520 { 1521 /* Add some entries to the .dynamic section. We fill in the 1522 values later, in elf_s390_finish_dynamic_sections, but we 1523 must add the entries now so that we get the correct size for 1524 the .dynamic section. The DT_DEBUG entry is filled in by the 1525 dynamic linker and used by the debugger. */ 1526#define add_dynamic_entry(TAG, VAL) \ 1527 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL)) 1528 1529 if (! info->shared) 1530 { 1531 if (!add_dynamic_entry (DT_DEBUG, 0)) 1532 return false; 1533 } 1534 1535 if (htab->splt->_raw_size != 0) 1536 { 1537 if (!add_dynamic_entry (DT_PLTGOT, 0) 1538 || !add_dynamic_entry (DT_PLTRELSZ, 0) 1539 || !add_dynamic_entry (DT_PLTREL, DT_RELA) 1540 || !add_dynamic_entry (DT_JMPREL, 0)) 1541 return false; 1542 } 1543 1544 if (relocs) 1545 { 1546 if (!add_dynamic_entry (DT_RELA, 0) 1547 || !add_dynamic_entry (DT_RELASZ, 0) 1548 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela))) 1549 return false; 1550 1551 /* If any dynamic relocs apply to a read-only section, 1552 then we need a DT_TEXTREL entry. */ 1553 if ((info->flags & DF_TEXTREL) == 0) 1554 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, 1555 (PTR) info); 1556 1557 if ((info->flags & DF_TEXTREL) != 0) 1558 { 1559 if (!add_dynamic_entry (DT_TEXTREL, 0)) 1560 return false; 1561 } 1562 } 1563 } 1564#undef add_dynamic_entry 1565 1566 return true; 1567} 1568 1569/* Relocate a 390 ELF section. */ 1570 1571static boolean 1572elf_s390_relocate_section (output_bfd, info, input_bfd, input_section, 1573 contents, relocs, local_syms, local_sections) 1574 bfd *output_bfd; 1575 struct bfd_link_info *info; 1576 bfd *input_bfd; 1577 asection *input_section; 1578 bfd_byte *contents; 1579 Elf_Internal_Rela *relocs; 1580 Elf_Internal_Sym *local_syms; 1581 asection **local_sections; 1582{ 1583 struct elf_s390_link_hash_table *htab; 1584 Elf_Internal_Shdr *symtab_hdr; 1585 struct elf_link_hash_entry **sym_hashes; 1586 bfd_vma *local_got_offsets; 1587 Elf_Internal_Rela *rel; 1588 Elf_Internal_Rela *relend; 1589 1590 if (info->relocateable) 1591 return true; 1592 1593 htab = elf_s390_hash_table (info); 1594 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; 1595 sym_hashes = elf_sym_hashes (input_bfd); 1596 local_got_offsets = elf_local_got_offsets (input_bfd); 1597 1598 rel = relocs; 1599 relend = relocs + input_section->reloc_count; 1600 for (; rel < relend; rel++) 1601 { 1602 int r_type; 1603 reloc_howto_type *howto; 1604 unsigned long r_symndx; 1605 struct elf_link_hash_entry *h; 1606 Elf_Internal_Sym *sym; 1607 asection *sec; 1608 bfd_vma off; 1609 bfd_vma relocation; 1610 boolean unresolved_reloc; 1611 bfd_reloc_status_type r; 1612 1613 r_type = ELF64_R_TYPE (rel->r_info); 1614 if (r_type == (int) R_390_GNU_VTINHERIT 1615 || r_type == (int) R_390_GNU_VTENTRY) 1616 continue; 1617 if (r_type < 0 || r_type >= (int) R_390_max) 1618 { 1619 bfd_set_error (bfd_error_bad_value); 1620 return false; 1621 } 1622 1623 howto = elf_howto_table + r_type; 1624 r_symndx = ELF64_R_SYM (rel->r_info); 1625 h = NULL; 1626 sym = NULL; 1627 sec = NULL; 1628 unresolved_reloc = false; 1629 if (r_symndx < symtab_hdr->sh_info) 1630 { 1631 sym = local_syms + r_symndx; 1632 sec = local_sections[r_symndx]; 1633 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, sec, rel); 1634 } 1635 else 1636 { 1637 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1638 while (h->root.type == bfd_link_hash_indirect 1639 || h->root.type == bfd_link_hash_warning) 1640 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1641 1642 if (h->root.type == bfd_link_hash_defined 1643 || h->root.type == bfd_link_hash_defweak) 1644 { 1645 sec = h->root.u.def.section; 1646 if (sec->output_section == NULL) 1647 { 1648 /* Set a flag that will be cleared later if we find a 1649 relocation value for this symbol. output_section 1650 is typically NULL for symbols satisfied by a shared 1651 library. */ 1652 unresolved_reloc = true; 1653 relocation = 0; 1654 } 1655 else 1656 relocation = (h->root.u.def.value 1657 + sec->output_section->vma 1658 + sec->output_offset); 1659 } 1660 else if (h->root.type == bfd_link_hash_undefweak) 1661 relocation = 0; 1662 else if (info->shared 1663 && (!info->symbolic || info->allow_shlib_undefined) 1664 && !info->no_undefined 1665 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT) 1666 relocation = 0; 1667 else 1668 { 1669 if (! ((*info->callbacks->undefined_symbol) 1670 (info, h->root.root.string, input_bfd, 1671 input_section, rel->r_offset, 1672 (!info->shared || info->no_undefined 1673 || ELF_ST_VISIBILITY (h->other))))) 1674 return false; 1675 relocation = 0; 1676 } 1677 } 1678 1679 switch (r_type) 1680 { 1681 case R_390_GOT12: 1682 case R_390_GOT16: 1683 case R_390_GOT32: 1684 case R_390_GOT64: 1685 case R_390_GOTENT: 1686 /* Relocation is to the entry for this symbol in the global 1687 offset table. */ 1688 if (htab->sgot == NULL) 1689 abort (); 1690 1691 if (h != NULL) 1692 { 1693 boolean dyn; 1694 1695 off = h->got.offset; 1696 dyn = htab->elf.dynamic_sections_created; 1697 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h) 1698 || (info->shared 1699 && (info->symbolic 1700 || h->dynindx == -1 1701 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL)) 1702 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))) 1703 { 1704 /* This is actually a static link, or it is a 1705 -Bsymbolic link and the symbol is defined 1706 locally, or the symbol was forced to be local 1707 because of a version file. We must initialize 1708 this entry in the global offset table. Since the 1709 offset must always be a multiple of 2, we use the 1710 least significant bit to record whether we have 1711 initialized it already. 1712 1713 When doing a dynamic link, we create a .rel.got 1714 relocation entry to initialize the value. This 1715 is done in the finish_dynamic_symbol routine. */ 1716 if ((off & 1) != 0) 1717 off &= ~1; 1718 else 1719 { 1720 bfd_put_64 (output_bfd, relocation, 1721 htab->sgot->contents + off); 1722 h->got.offset |= 1; 1723 } 1724 } 1725 else 1726 unresolved_reloc = false; 1727 } 1728 else 1729 { 1730 if (local_got_offsets == NULL) 1731 abort (); 1732 1733 off = local_got_offsets[r_symndx]; 1734 1735 /* The offset must always be a multiple of 8. We use 1736 the least significant bit to record whether we have 1737 already generated the necessary reloc. */ 1738 if ((off & 1) != 0) 1739 off &= ~1; 1740 else 1741 { 1742 bfd_put_64 (output_bfd, relocation, 1743 htab->sgot->contents + off); 1744 1745 if (info->shared) 1746 { 1747 asection *srelgot; 1748 Elf_Internal_Rela outrel; 1749 Elf64_External_Rela *loc; 1750 1751 srelgot = htab->srelgot; 1752 if (srelgot == NULL) 1753 abort (); 1754 1755 outrel.r_offset = (htab->sgot->output_section->vma 1756 + htab->sgot->output_offset 1757 + off); 1758 outrel.r_info = ELF64_R_INFO (0, R_390_RELATIVE); 1759 outrel.r_addend = relocation; 1760 loc = (Elf64_External_Rela *) srelgot->contents; 1761 loc += srelgot->reloc_count++; 1762 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 1763 } 1764 1765 local_got_offsets[r_symndx] |= 1; 1766 } 1767 } 1768 1769 if (off >= (bfd_vma) -2) 1770 abort (); 1771 1772 relocation = htab->sgot->output_offset + off; 1773 1774 /* 1775 * For @GOTENT the relocation is against the offset between 1776 * the instruction and the symbols entry in the GOT and not 1777 * between the start of the GOT and the symbols entry. We 1778 * add the vma of the GOT to get the correct value. 1779 */ 1780 if (r_type == R_390_GOTENT) 1781 relocation += htab->sgot->output_section->vma; 1782 1783 break; 1784 1785 case R_390_GOTOFF: 1786 /* Relocation is relative to the start of the global offset 1787 table. */ 1788 1789 /* Note that sgot->output_offset is not involved in this 1790 calculation. We always want the start of .got. If we 1791 defined _GLOBAL_OFFSET_TABLE in a different way, as is 1792 permitted by the ABI, we might have to change this 1793 calculation. */ 1794 relocation -= htab->sgot->output_section->vma; 1795 1796 break; 1797 1798 case R_390_GOTPC: 1799 case R_390_GOTPCDBL: 1800 /* Use global offset table as symbol value. */ 1801 relocation = htab->sgot->output_section->vma; 1802 unresolved_reloc = false; 1803 break; 1804 1805 case R_390_PLT16DBL: 1806 case R_390_PLT32: 1807 case R_390_PLT32DBL: 1808 case R_390_PLT64: 1809 /* Relocation is to the entry for this symbol in the 1810 procedure linkage table. */ 1811 1812 /* Resolve a PLT32 reloc against a local symbol directly, 1813 without using the procedure linkage table. */ 1814 if (h == NULL) 1815 break; 1816 1817 if (h->plt.offset == (bfd_vma) -1 1818 || htab->splt == NULL) 1819 { 1820 /* We didn't make a PLT entry for this symbol. This 1821 happens when statically linking PIC code, or when 1822 using -Bsymbolic. */ 1823 break; 1824 } 1825 1826 relocation = (htab->splt->output_section->vma 1827 + htab->splt->output_offset 1828 + h->plt.offset); 1829 unresolved_reloc = false; 1830 break; 1831 1832 case R_390_8: 1833 case R_390_16: 1834 case R_390_32: 1835 case R_390_64: 1836 case R_390_PC16: 1837 case R_390_PC16DBL: 1838 case R_390_PC32: 1839 case R_390_PC32DBL: 1840 case R_390_PC64: 1841 /* r_symndx will be zero only for relocs against symbols 1842 from removed linkonce sections, or sections discarded by 1843 a linker script. */ 1844 if (r_symndx == 0 1845 || (input_section->flags & SEC_ALLOC) == 0) 1846 break; 1847 1848 if ((info->shared 1849 && ((r_type != R_390_PC16 1850 && r_type != R_390_PC16DBL 1851 && r_type != R_390_PC32 1852 && r_type != R_390_PC32DBL 1853 && r_type != R_390_PC64) 1854 || (h != NULL 1855 && h->dynindx != -1 1856 && (! info->symbolic 1857 || (h->elf_link_hash_flags 1858 & ELF_LINK_HASH_DEF_REGULAR) == 0)))) 1859 || (!info->shared 1860 && h != NULL 1861 && h->dynindx != -1 1862 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0 1863 && (((h->elf_link_hash_flags 1864 & ELF_LINK_HASH_DEF_DYNAMIC) != 0 1865 && (h->elf_link_hash_flags 1866 & ELF_LINK_HASH_DEF_REGULAR) == 0) 1867 || h->root.type == bfd_link_hash_undefweak 1868 || h->root.type == bfd_link_hash_undefined))) 1869 { 1870 Elf_Internal_Rela outrel; 1871 boolean skip, relocate; 1872 asection *sreloc; 1873 Elf64_External_Rela *loc; 1874 1875 /* When generating a shared object, these relocations 1876 are copied into the output file to be resolved at run 1877 time. */ 1878 1879 skip = false; 1880 relocate = false; 1881 1882 outrel.r_offset = 1883 _bfd_elf_section_offset (output_bfd, info, input_section, 1884 rel->r_offset); 1885 if (outrel.r_offset == (bfd_vma) -1) 1886 skip = true; 1887 else if (outrel.r_offset == (bfd_vma) -2) 1888 skip = true, relocate = true; 1889 1890 outrel.r_offset += (input_section->output_section->vma 1891 + input_section->output_offset); 1892 1893 if (skip) 1894 memset (&outrel, 0, sizeof outrel); 1895 else if (h != NULL 1896 && h->dynindx != -1 1897 && (r_type == R_390_PC16 1898 || r_type == R_390_PC16DBL 1899 || r_type == R_390_PC32 1900 || r_type == R_390_PC32DBL 1901 || r_type == R_390_PC64 1902 || !info->shared 1903 || !info->symbolic 1904 || (h->elf_link_hash_flags 1905 & ELF_LINK_HASH_DEF_REGULAR) == 0)) 1906 { 1907 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type); 1908 outrel.r_addend = rel->r_addend; 1909 } 1910 else 1911 { 1912 /* This symbol is local, or marked to become local. */ 1913 relocate = true; 1914 outrel.r_info = ELF64_R_INFO (0, R_390_RELATIVE); 1915 outrel.r_addend = relocation + rel->r_addend; 1916 } 1917 1918 sreloc = elf_section_data (input_section)->sreloc; 1919 if (sreloc == NULL) 1920 abort (); 1921 1922 loc = (Elf64_External_Rela *) sreloc->contents; 1923 loc += sreloc->reloc_count++; 1924 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 1925 1926 /* If this reloc is against an external symbol, we do 1927 not want to fiddle with the addend. Otherwise, we 1928 need to include the symbol value so that it becomes 1929 an addend for the dynamic reloc. */ 1930 if (! relocate) 1931 continue; 1932 } 1933 1934 break; 1935 1936 default: 1937 break; 1938 } 1939 1940 if (unresolved_reloc 1941 && !(info->shared 1942 && (input_section->flags & SEC_DEBUGGING) != 0 1943 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)) 1944 (*_bfd_error_handler) 1945 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"), 1946 bfd_archive_filename (input_bfd), 1947 bfd_get_section_name (input_bfd, input_section), 1948 (long) rel->r_offset, 1949 h->root.root.string); 1950 1951 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 1952 contents, rel->r_offset, 1953 relocation, rel->r_addend); 1954 1955 if (r != bfd_reloc_ok) 1956 { 1957 const char *name; 1958 1959 if (h != NULL) 1960 name = h->root.root.string; 1961 else 1962 { 1963 name = bfd_elf_string_from_elf_section (input_bfd, 1964 symtab_hdr->sh_link, 1965 sym->st_name); 1966 if (name == NULL) 1967 return false; 1968 if (*name == '\0') 1969 name = bfd_section_name (input_bfd, sec); 1970 } 1971 1972 if (r == bfd_reloc_overflow) 1973 { 1974 1975 if (! ((*info->callbacks->reloc_overflow) 1976 (info, name, howto->name, (bfd_vma) 0, 1977 input_bfd, input_section, rel->r_offset))) 1978 return false; 1979 } 1980 else 1981 { 1982 (*_bfd_error_handler) 1983 (_("%s(%s+0x%lx): reloc against `%s': error %d"), 1984 bfd_archive_filename (input_bfd), 1985 bfd_get_section_name (input_bfd, input_section), 1986 (long) rel->r_offset, name, (int) r); 1987 return false; 1988 } 1989 } 1990 } 1991 1992 return true; 1993} 1994 1995/* Finish up dynamic symbol handling. We set the contents of various 1996 dynamic sections here. */ 1997 1998static boolean 1999elf_s390_finish_dynamic_symbol (output_bfd, info, h, sym) 2000 bfd *output_bfd; 2001 struct bfd_link_info *info; 2002 struct elf_link_hash_entry *h; 2003 Elf_Internal_Sym *sym; 2004{ 2005 struct elf_s390_link_hash_table *htab; 2006 2007 htab = elf_s390_hash_table (info); 2008 2009 if (h->plt.offset != (bfd_vma) -1) 2010 { 2011 bfd_vma plt_index; 2012 bfd_vma got_offset; 2013 Elf_Internal_Rela rela; 2014 Elf64_External_Rela *loc; 2015 2016 /* This symbol has an entry in the procedure linkage table. Set 2017 it up. */ 2018 2019 if (h->dynindx == -1 2020 || htab->splt == NULL 2021 || htab->sgotplt == NULL 2022 || htab->srelplt == NULL) 2023 abort (); 2024 2025 /* Calc. index no. 2026 Current offset - size first entry / entry size. */ 2027 plt_index = (h->plt.offset - PLT_FIRST_ENTRY_SIZE) / PLT_ENTRY_SIZE; 2028 2029 /* Offset in GOT is PLT index plus GOT headers(3) times 8, 2030 addr & GOT addr. */ 2031 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE; 2032 2033 /* Fill in the blueprint of a PLT. */ 2034 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD0, 2035 htab->splt->contents + h->plt.offset); 2036 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD1, 2037 htab->splt->contents + h->plt.offset + 4); 2038 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD2, 2039 htab->splt->contents + h->plt.offset + 8); 2040 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD3, 2041 htab->splt->contents + h->plt.offset + 12); 2042 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD4, 2043 htab->splt->contents + h->plt.offset + 16); 2044 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD5, 2045 htab->splt->contents + h->plt.offset + 20); 2046 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD6, 2047 htab->splt->contents + h->plt.offset + 24); 2048 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD7, 2049 htab->splt->contents + h->plt.offset + 28); 2050 /* Fixup the relative address to the GOT entry */ 2051 bfd_put_32 (output_bfd, 2052 (htab->sgotplt->output_section->vma + 2053 htab->sgotplt->output_offset + got_offset 2054 - (htab->splt->output_section->vma + h->plt.offset))/2, 2055 htab->splt->contents + h->plt.offset + 2); 2056 /* Fixup the relative branch to PLT 0 */ 2057 bfd_put_32 (output_bfd, - (PLT_FIRST_ENTRY_SIZE + 2058 (PLT_ENTRY_SIZE * plt_index) + 22)/2, 2059 htab->splt->contents + h->plt.offset + 24); 2060 /* Fixup offset into symbol table */ 2061 bfd_put_32 (output_bfd, plt_index * sizeof (Elf64_External_Rela), 2062 htab->splt->contents + h->plt.offset + 28); 2063 2064 /* Fill in the entry in the global offset table. 2065 Points to instruction after GOT offset. */ 2066 bfd_put_64 (output_bfd, 2067 (htab->splt->output_section->vma 2068 + htab->splt->output_offset 2069 + h->plt.offset 2070 + 14), 2071 htab->sgotplt->contents + got_offset); 2072 2073 /* Fill in the entry in the .rela.plt section. */ 2074 rela.r_offset = (htab->sgotplt->output_section->vma 2075 + htab->sgotplt->output_offset 2076 + got_offset); 2077 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_JMP_SLOT); 2078 rela.r_addend = 0; 2079 loc = (Elf64_External_Rela *) htab->srelplt->contents + plt_index; 2080 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 2081 2082 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) 2083 { 2084 /* Mark the symbol as undefined, rather than as defined in 2085 the .plt section. Leave the value alone. This is a clue 2086 for the dynamic linker, to make function pointer 2087 comparisons work between an application and shared 2088 library. */ 2089 sym->st_shndx = SHN_UNDEF; 2090 } 2091 } 2092 2093 if (h->got.offset != (bfd_vma) -1) 2094 { 2095 Elf_Internal_Rela rela; 2096 Elf64_External_Rela *loc; 2097 2098 /* This symbol has an entry in the global offset table. Set it 2099 up. */ 2100 2101 if (htab->sgot == NULL || htab->srelgot == NULL) 2102 abort (); 2103 2104 rela.r_offset = (htab->sgot->output_section->vma 2105 + htab->sgot->output_offset 2106 + (h->got.offset &~ (bfd_vma) 1)); 2107 2108 /* If this is a static link, or it is a -Bsymbolic link and the 2109 symbol is defined locally or was forced to be local because 2110 of a version file, we just want to emit a RELATIVE reloc. 2111 The entry in the global offset table will already have been 2112 initialized in the relocate_section function. */ 2113 if (info->shared 2114 && (info->symbolic 2115 || h->dynindx == -1 2116 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL)) 2117 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)) 2118 { 2119 BFD_ASSERT((h->got.offset & 1) != 0); 2120 rela.r_info = ELF64_R_INFO (0, R_390_RELATIVE); 2121 rela.r_addend = (h->root.u.def.value 2122 + h->root.u.def.section->output_section->vma 2123 + h->root.u.def.section->output_offset); 2124 } 2125 else 2126 { 2127 BFD_ASSERT((h->got.offset & 1) == 0); 2128 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgot->contents + h->got.offset); 2129 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_GLOB_DAT); 2130 rela.r_addend = 0; 2131 } 2132 2133 loc = (Elf64_External_Rela *) htab->srelgot->contents; 2134 loc += htab->srelgot->reloc_count++; 2135 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 2136 } 2137 2138 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0) 2139 { 2140 Elf_Internal_Rela rela; 2141 Elf64_External_Rela *loc; 2142 2143 /* This symbols needs a copy reloc. Set it up. */ 2144 2145 if (h->dynindx == -1 2146 || (h->root.type != bfd_link_hash_defined 2147 && h->root.type != bfd_link_hash_defweak) 2148 || htab->srelbss == NULL) 2149 abort (); 2150 2151 rela.r_offset = (h->root.u.def.value 2152 + h->root.u.def.section->output_section->vma 2153 + h->root.u.def.section->output_offset); 2154 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_COPY); 2155 rela.r_addend = 0; 2156 loc = (Elf64_External_Rela *) htab->srelbss->contents; 2157 loc += htab->srelbss->reloc_count++; 2158 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 2159 } 2160 2161 /* Mark some specially defined symbols as absolute. */ 2162 if (strcmp (h->root.root.string, "_DYNAMIC") == 0 2163 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0 2164 || strcmp (h->root.root.string, "_PROCEDURE_LINKAGE_TABLE_") == 0) 2165 sym->st_shndx = SHN_ABS; 2166 2167 return true; 2168} 2169 2170/* Used to decide how to sort relocs in an optimal manner for the 2171 dynamic linker, before writing them out. */ 2172 2173static enum elf_reloc_type_class 2174elf_s390_reloc_type_class (rela) 2175 const Elf_Internal_Rela *rela; 2176{ 2177 switch ((int) ELF64_R_TYPE (rela->r_info)) 2178 { 2179 case R_390_RELATIVE: 2180 return reloc_class_relative; 2181 case R_390_JMP_SLOT: 2182 return reloc_class_plt; 2183 case R_390_COPY: 2184 return reloc_class_copy; 2185 default: 2186 return reloc_class_normal; 2187 } 2188} 2189 2190/* Finish up the dynamic sections. */ 2191 2192static boolean 2193elf_s390_finish_dynamic_sections (output_bfd, info) 2194 bfd *output_bfd; 2195 struct bfd_link_info *info; 2196{ 2197 struct elf_s390_link_hash_table *htab; 2198 bfd *dynobj; 2199 asection *sdyn; 2200 2201 htab = elf_s390_hash_table (info); 2202 dynobj = htab->elf.dynobj; 2203 sdyn = bfd_get_section_by_name (dynobj, ".dynamic"); 2204 2205 if (htab->elf.dynamic_sections_created) 2206 { 2207 Elf64_External_Dyn *dyncon, *dynconend; 2208 2209 if (sdyn == NULL || htab->sgot == NULL) 2210 abort (); 2211 2212 dyncon = (Elf64_External_Dyn *) sdyn->contents; 2213 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size); 2214 for (; dyncon < dynconend; dyncon++) 2215 { 2216 Elf_Internal_Dyn dyn; 2217 asection *s; 2218 2219 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn); 2220 2221 switch (dyn.d_tag) 2222 { 2223 default: 2224 continue; 2225 2226 case DT_PLTGOT: 2227 dyn.d_un.d_ptr = htab->sgot->output_section->vma; 2228 break; 2229 2230 case DT_JMPREL: 2231 dyn.d_un.d_ptr = htab->srelplt->output_section->vma; 2232 break; 2233 2234 case DT_PLTRELSZ: 2235 s = htab->srelplt->output_section; 2236 if (s->_cooked_size != 0) 2237 dyn.d_un.d_val = s->_cooked_size; 2238 else 2239 dyn.d_un.d_val = s->_raw_size; 2240 break; 2241 2242 case DT_RELASZ: 2243 /* The procedure linkage table relocs (DT_JMPREL) should 2244 not be included in the overall relocs (DT_RELA). 2245 Therefore, we override the DT_RELASZ entry here to 2246 make it not include the JMPREL relocs. Since the 2247 linker script arranges for .rela.plt to follow all 2248 other relocation sections, we don't have to worry 2249 about changing the DT_RELA entry. */ 2250 s = htab->srelplt->output_section; 2251 if (s->_cooked_size != 0) 2252 dyn.d_un.d_val -= s->_cooked_size; 2253 else 2254 dyn.d_un.d_val -= s->_raw_size; 2255 break; 2256 } 2257 2258 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon); 2259 } 2260 2261 /* Fill in the special first entry in the procedure linkage table. */ 2262 if (htab->splt && htab->splt->_raw_size > 0) 2263 { 2264 /* fill in blueprint for plt 0 entry */ 2265 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD0, 2266 htab->splt->contents ); 2267 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD1, 2268 htab->splt->contents +4 ); 2269 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD3, 2270 htab->splt->contents +12 ); 2271 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD4, 2272 htab->splt->contents +16 ); 2273 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD5, 2274 htab->splt->contents +20 ); 2275 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD6, 2276 htab->splt->contents + 24); 2277 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD7, 2278 htab->splt->contents + 28 ); 2279 /* Fixup relative address to start of GOT */ 2280 bfd_put_32 (output_bfd, 2281 (htab->sgotplt->output_section->vma + 2282 htab->sgotplt->output_offset 2283 - htab->splt->output_section->vma - 6)/2, 2284 htab->splt->contents + 8); 2285 } 2286 elf_section_data (htab->splt->output_section) 2287 ->this_hdr.sh_entsize = PLT_ENTRY_SIZE; 2288 } 2289 2290 if (htab->sgotplt) 2291 { 2292 /* Fill in the first three entries in the global offset table. */ 2293 if (htab->sgotplt->_raw_size > 0) 2294 { 2295 bfd_put_64 (output_bfd, 2296 (sdyn == NULL ? (bfd_vma) 0 2297 : sdyn->output_section->vma + sdyn->output_offset), 2298 htab->sgotplt->contents); 2299 /* One entry for shared object struct ptr. */ 2300 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 8); 2301 /* One entry for _dl_runtime_resolve. */ 2302 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 12); 2303 } 2304 2305 elf_section_data (htab->sgot->output_section) 2306 ->this_hdr.sh_entsize = 8; 2307 } 2308 return true; 2309} 2310 2311static boolean 2312elf_s390_object_p (abfd) 2313 bfd *abfd; 2314{ 2315 return bfd_default_set_arch_mach (abfd, bfd_arch_s390, bfd_mach_s390_64); 2316} 2317 2318/* 2319 * Why was the hash table entry size definition changed from 2320 * ARCH_SIZE/8 to 4? This breaks the 64 bit dynamic linker and 2321 * this is the only reason for the s390_elf64_size_info structure. 2322 */ 2323 2324const struct elf_size_info s390_elf64_size_info = 2325{ 2326 sizeof (Elf64_External_Ehdr), 2327 sizeof (Elf64_External_Phdr), 2328 sizeof (Elf64_External_Shdr), 2329 sizeof (Elf64_External_Rel), 2330 sizeof (Elf64_External_Rela), 2331 sizeof (Elf64_External_Sym), 2332 sizeof (Elf64_External_Dyn), 2333 sizeof (Elf_External_Note), 2334 8, /* hash-table entry size */ 2335 1, /* internal relocations per external relocations */ 2336 64, /* arch_size */ 2337 8, /* file_align */ 2338 ELFCLASS64, EV_CURRENT, 2339 bfd_elf64_write_out_phdrs, 2340 bfd_elf64_write_shdrs_and_ehdr, 2341 bfd_elf64_write_relocs, 2342 bfd_elf64_swap_symbol_out, 2343 bfd_elf64_slurp_reloc_table, 2344 bfd_elf64_slurp_symbol_table, 2345 bfd_elf64_swap_dyn_in, 2346 bfd_elf64_swap_dyn_out, 2347 NULL, 2348 NULL, 2349 NULL, 2350 NULL 2351}; 2352 2353#define TARGET_BIG_SYM bfd_elf64_s390_vec 2354#define TARGET_BIG_NAME "elf64-s390" 2355#define ELF_ARCH bfd_arch_s390 2356#define ELF_MACHINE_CODE EM_S390 2357#define ELF_MACHINE_ALT1 EM_S390_OLD 2358#define ELF_MAXPAGESIZE 0x1000 2359 2360#define elf_backend_size_info s390_elf64_size_info 2361 2362#define elf_backend_can_gc_sections 1 2363#define elf_backend_can_refcount 1 2364#define elf_backend_want_got_plt 1 2365#define elf_backend_plt_readonly 1 2366#define elf_backend_want_plt_sym 0 2367#define elf_backend_got_header_size 24 2368#define elf_backend_plt_header_size PLT_ENTRY_SIZE 2369#define elf_backend_rela_normal 1 2370 2371#define elf_info_to_howto elf_s390_info_to_howto 2372 2373#define bfd_elf64_bfd_is_local_label_name elf_s390_is_local_label_name 2374#define bfd_elf64_bfd_link_hash_table_create elf_s390_link_hash_table_create 2375#define bfd_elf64_bfd_reloc_type_lookup elf_s390_reloc_type_lookup 2376 2377#define elf_backend_adjust_dynamic_symbol elf_s390_adjust_dynamic_symbol 2378#define elf_backend_check_relocs elf_s390_check_relocs 2379#define elf_backend_copy_indirect_symbol elf_s390_copy_indirect_symbol 2380#define elf_backend_create_dynamic_sections elf_s390_create_dynamic_sections 2381#define elf_backend_finish_dynamic_sections elf_s390_finish_dynamic_sections 2382#define elf_backend_finish_dynamic_symbol elf_s390_finish_dynamic_symbol 2383#define elf_backend_gc_mark_hook elf_s390_gc_mark_hook 2384#define elf_backend_gc_sweep_hook elf_s390_gc_sweep_hook 2385#define elf_backend_reloc_type_class elf_s390_reloc_type_class 2386#define elf_backend_relocate_section elf_s390_relocate_section 2387#define elf_backend_size_dynamic_sections elf_s390_size_dynamic_sections 2388#define elf_backend_reloc_type_class elf_s390_reloc_type_class 2389 2390#define elf_backend_object_p elf_s390_object_p 2391 2392#include "elf64-target.h" 2393