2002-01-31 Michael Snyder <msnyder@redhat.com>
[deliverable/binutils-gdb.git] / bfd / elf64-s390.c
1 /* IBM S/390-specific support for 64-bit ELF
2 Copyright 2000, 2001 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
28 static reloc_howto_type *elf_s390_reloc_type_lookup
29 PARAMS ((bfd *, bfd_reloc_code_real_type));
30 static void elf_s390_info_to_howto
31 PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));
32 static boolean elf_s390_is_local_label_name
33 PARAMS ((bfd *, const char *));
34 static struct bfd_hash_entry *link_hash_newfunc
35 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
36 static struct bfd_link_hash_table *elf_s390_link_hash_table_create
37 PARAMS ((bfd *));
38 static boolean create_got_section
39 PARAMS((bfd *, struct bfd_link_info *));
40 static boolean elf_s390_create_dynamic_sections
41 PARAMS((bfd *, struct bfd_link_info *));
42 static void elf_s390_copy_indirect_symbol
43 PARAMS ((struct elf_link_hash_entry *, struct elf_link_hash_entry *));
44 static boolean elf_s390_check_relocs
45 PARAMS ((bfd *, struct bfd_link_info *, asection *,
46 const Elf_Internal_Rela *));
47 static 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 *));
50 static boolean elf_s390_gc_sweep_hook
51 PARAMS ((bfd *, struct bfd_link_info *, asection *,
52 const Elf_Internal_Rela *));
53 static boolean elf_s390_adjust_dynamic_symbol
54 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
55 static boolean allocate_dynrelocs
56 PARAMS ((struct elf_link_hash_entry *, PTR));
57 static boolean readonly_dynrelocs
58 PARAMS ((struct elf_link_hash_entry *, PTR));
59 static boolean elf_s390_size_dynamic_sections
60 PARAMS ((bfd *, struct bfd_link_info *));
61 static boolean elf_s390_relocate_section
62 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
63 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
64 static boolean elf_s390_finish_dynamic_symbol
65 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
66 Elf_Internal_Sym *));
67 static enum elf_reloc_type_class elf_s390_reloc_type_class
68 PARAMS ((const Elf_Internal_Rela *));
69 static boolean elf_s390_finish_dynamic_sections
70 PARAMS ((bfd *, struct bfd_link_info *));
71 static 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. */
82 static 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. */
127 static 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);
129 static 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
132 static reloc_howto_type *
133 elf_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
208 static void
209 elf_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
230 static boolean
231 elf_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
339 struct 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
355 struct 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
365 struct 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
389 static struct bfd_hash_entry *
390 link_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
420 static struct bfd_link_hash_table *
421 elf_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
452 static boolean
453 create_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
483 static boolean
484 elf_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
512 static void
513 elf_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
562 static boolean
563 elf_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
857 static asection *
858 elf_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
898 static boolean
899 elf_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
1009 static boolean
1010 elf_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
1162 static boolean
1163 allocate_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 || h->root.type == bfd_link_hash_warning)
1174 return true;
1175
1176 info = (struct bfd_link_info *) inf;
1177 htab = elf_s390_hash_table (info);
1178
1179 if (htab->elf.dynamic_sections_created
1180 && h->plt.refcount > 0)
1181 {
1182 /* Make sure this symbol is output as a dynamic symbol.
1183 Undefined weak syms won't yet be marked as dynamic. */
1184 if (h->dynindx == -1
1185 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1186 {
1187 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1188 return false;
1189 }
1190
1191 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h))
1192 {
1193 asection *s = htab->splt;
1194
1195 /* If this is the first .plt entry, make room for the special
1196 first entry. */
1197 if (s->_raw_size == 0)
1198 s->_raw_size += PLT_FIRST_ENTRY_SIZE;
1199
1200 h->plt.offset = s->_raw_size;
1201
1202 /* If this symbol is not defined in a regular file, and we are
1203 not generating a shared library, then set the symbol to this
1204 location in the .plt. This is required to make function
1205 pointers compare as equal between the normal executable and
1206 the shared library. */
1207 if (! info->shared
1208 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1209 {
1210 h->root.u.def.section = s;
1211 h->root.u.def.value = h->plt.offset;
1212 }
1213
1214 /* Make room for this entry. */
1215 s->_raw_size += PLT_ENTRY_SIZE;
1216
1217 /* We also need to make an entry in the .got.plt section, which
1218 will be placed in the .got section by the linker script. */
1219 htab->sgotplt->_raw_size += GOT_ENTRY_SIZE;
1220
1221 /* We also need to make an entry in the .rela.plt section. */
1222 htab->srelplt->_raw_size += sizeof (Elf64_External_Rela);
1223 }
1224 else
1225 {
1226 h->plt.offset = (bfd_vma) -1;
1227 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1228 }
1229 }
1230 else
1231 {
1232 h->plt.offset = (bfd_vma) -1;
1233 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1234 }
1235
1236 if (h->got.refcount > 0)
1237 {
1238 asection *s;
1239 boolean dyn;
1240
1241 /* Make sure this symbol is output as a dynamic symbol.
1242 Undefined weak syms won't yet be marked as dynamic. */
1243 if (h->dynindx == -1
1244 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1245 {
1246 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1247 return false;
1248 }
1249
1250 s = htab->sgot;
1251 h->got.offset = s->_raw_size;
1252 s->_raw_size += GOT_ENTRY_SIZE;
1253 dyn = htab->elf.dynamic_sections_created;
1254 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
1255 htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
1256 }
1257 else
1258 h->got.offset = (bfd_vma) -1;
1259
1260 eh = (struct elf_s390_link_hash_entry *) h;
1261 if (eh->dyn_relocs == NULL)
1262 return true;
1263
1264 /* In the shared -Bsymbolic case, discard space allocated for
1265 dynamic pc-relative relocs against symbols which turn out to be
1266 defined in regular objects. For the normal shared case, discard
1267 space for pc-relative relocs that have become local due to symbol
1268 visibility changes. */
1269
1270 if (info->shared)
1271 {
1272 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1273 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1274 || info->symbolic))
1275 {
1276 struct elf_s390_dyn_relocs **pp;
1277
1278 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1279 {
1280 p->count -= p->pc_count;
1281 p->pc_count = 0;
1282 if (p->count == 0)
1283 *pp = p->next;
1284 else
1285 pp = &p->next;
1286 }
1287 }
1288 }
1289 else
1290 {
1291 /* For the non-shared case, discard space for relocs against
1292 symbols which turn out to need copy relocs or are not
1293 dynamic. */
1294
1295 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1296 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1297 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1298 || (htab->elf.dynamic_sections_created
1299 && (h->root.type == bfd_link_hash_undefweak
1300 || h->root.type == bfd_link_hash_undefined))))
1301 {
1302 /* Make sure this symbol is output as a dynamic symbol.
1303 Undefined weak syms won't yet be marked as dynamic. */
1304 if (h->dynindx == -1
1305 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1306 {
1307 if (! bfd_elf64_link_record_dynamic_symbol (info, h))
1308 return false;
1309 }
1310
1311 /* If that succeeded, we know we'll be keeping all the
1312 relocs. */
1313 if (h->dynindx != -1)
1314 goto keep;
1315 }
1316
1317 eh->dyn_relocs = NULL;
1318
1319 keep: ;
1320 }
1321
1322 /* Finally, allocate space. */
1323 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1324 {
1325 asection *sreloc = elf_section_data (p->sec)->sreloc;
1326 sreloc->_raw_size += p->count * sizeof (Elf64_External_Rela);
1327 }
1328
1329 return true;
1330 }
1331
1332 /* Find any dynamic relocs that apply to read-only sections. */
1333
1334 static boolean
1335 readonly_dynrelocs (h, inf)
1336 struct elf_link_hash_entry *h;
1337 PTR inf;
1338 {
1339 struct elf_s390_link_hash_entry *eh;
1340 struct elf_s390_dyn_relocs *p;
1341
1342 eh = (struct elf_s390_link_hash_entry *) h;
1343 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1344 {
1345 asection *s = p->sec->output_section;
1346
1347 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1348 {
1349 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1350
1351 info->flags |= DF_TEXTREL;
1352
1353 /* Not an error, just cut short the traversal. */
1354 return false;
1355 }
1356 }
1357 return true;
1358 }
1359
1360 /* Set the sizes of the dynamic sections. */
1361
1362 static boolean
1363 elf_s390_size_dynamic_sections (output_bfd, info)
1364 bfd *output_bfd ATTRIBUTE_UNUSED;
1365 struct bfd_link_info *info;
1366 {
1367 struct elf_s390_link_hash_table *htab;
1368 bfd *dynobj;
1369 asection *s;
1370 boolean relocs;
1371 bfd *ibfd;
1372
1373 htab = elf_s390_hash_table (info);
1374 dynobj = htab->elf.dynobj;
1375 if (dynobj == NULL)
1376 abort ();
1377
1378 if (htab->elf.dynamic_sections_created)
1379 {
1380 /* Set the contents of the .interp section to the interpreter. */
1381 if (! info->shared)
1382 {
1383 s = bfd_get_section_by_name (dynobj, ".interp");
1384 if (s == NULL)
1385 abort ();
1386 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1387 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1388 }
1389 }
1390
1391 /* Set up .got offsets for local syms, and space for local dynamic
1392 relocs. */
1393 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1394 {
1395 bfd_signed_vma *local_got;
1396 bfd_signed_vma *end_local_got;
1397 bfd_size_type locsymcount;
1398 Elf_Internal_Shdr *symtab_hdr;
1399 asection *srela;
1400
1401 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1402 continue;
1403
1404 for (s = ibfd->sections; s != NULL; s = s->next)
1405 {
1406 struct elf_s390_dyn_relocs *p;
1407
1408 for (p = *((struct elf_s390_dyn_relocs **)
1409 &elf_section_data (s)->local_dynrel);
1410 p != NULL;
1411 p = p->next)
1412 {
1413 if (!bfd_is_abs_section (p->sec)
1414 && bfd_is_abs_section (p->sec->output_section))
1415 {
1416 /* Input section has been discarded, either because
1417 it is a copy of a linkonce section or due to
1418 linker script /DISCARD/, so we'll be discarding
1419 the relocs too. */
1420 }
1421 else
1422 {
1423 srela = elf_section_data (p->sec)->sreloc;
1424 srela->_raw_size += p->count * sizeof (Elf64_External_Rela);
1425 }
1426 }
1427 }
1428
1429 local_got = elf_local_got_refcounts (ibfd);
1430 if (!local_got)
1431 continue;
1432
1433 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1434 locsymcount = symtab_hdr->sh_info;
1435 end_local_got = local_got + locsymcount;
1436 s = htab->sgot;
1437 srela = htab->srelgot;
1438 for (; local_got < end_local_got; ++local_got)
1439 {
1440 if (*local_got > 0)
1441 {
1442 *local_got = s->_raw_size;
1443 s->_raw_size += GOT_ENTRY_SIZE;
1444 if (info->shared)
1445 srela->_raw_size += sizeof (Elf64_External_Rela);
1446 }
1447 else
1448 *local_got = (bfd_vma) -1;
1449 }
1450 }
1451
1452 /* Allocate global sym .plt and .got entries, and space for global
1453 sym dynamic relocs. */
1454 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1455
1456 /* We now have determined the sizes of the various dynamic sections.
1457 Allocate memory for them. */
1458 relocs = false;
1459 for (s = dynobj->sections; s != NULL; s = s->next)
1460 {
1461 if ((s->flags & SEC_LINKER_CREATED) == 0)
1462 continue;
1463
1464 if (s == htab->splt
1465 || s == htab->sgot
1466 || s == htab->sgotplt)
1467 {
1468 /* Strip this section if we don't need it; see the
1469 comment below. */
1470 }
1471 else if (strncmp (bfd_get_section_name (dynobj, s), ".rela", 5) == 0)
1472 {
1473 if (s->_raw_size != 0 && s != htab->srelplt)
1474 relocs = true;
1475
1476 /* We use the reloc_count field as a counter if we need
1477 to copy relocs into the output file. */
1478 s->reloc_count = 0;
1479 }
1480 else
1481 {
1482 /* It's not one of our sections, so don't allocate space. */
1483 continue;
1484 }
1485
1486 if (s->_raw_size == 0)
1487 {
1488 /* If we don't need this section, strip it from the
1489 output file. This is to handle .rela.bss and
1490 .rela.plt. We must create it in
1491 create_dynamic_sections, because it must be created
1492 before the linker maps input sections to output
1493 sections. The linker does that before
1494 adjust_dynamic_symbol is called, and it is that
1495 function which decides whether anything needs to go
1496 into these sections. */
1497
1498 _bfd_strip_section_from_output (info, s);
1499 continue;
1500 }
1501
1502 /* Allocate memory for the section contents. We use bfd_zalloc
1503 here in case unused entries are not reclaimed before the
1504 section's contents are written out. This should not happen,
1505 but this way if it does, we get a R_390_NONE reloc instead
1506 of garbage. */
1507 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1508 if (s->contents == NULL)
1509 return false;
1510 }
1511
1512 if (htab->elf.dynamic_sections_created)
1513 {
1514 /* Add some entries to the .dynamic section. We fill in the
1515 values later, in elf_s390_finish_dynamic_sections, but we
1516 must add the entries now so that we get the correct size for
1517 the .dynamic section. The DT_DEBUG entry is filled in by the
1518 dynamic linker and used by the debugger. */
1519 #define add_dynamic_entry(TAG, VAL) \
1520 bfd_elf64_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1521
1522 if (! info->shared)
1523 {
1524 if (!add_dynamic_entry (DT_DEBUG, 0))
1525 return false;
1526 }
1527
1528 if (htab->splt->_raw_size != 0)
1529 {
1530 if (!add_dynamic_entry (DT_PLTGOT, 0)
1531 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1532 || !add_dynamic_entry (DT_PLTREL, DT_RELA)
1533 || !add_dynamic_entry (DT_JMPREL, 0))
1534 return false;
1535 }
1536
1537 if (relocs)
1538 {
1539 if (!add_dynamic_entry (DT_RELA, 0)
1540 || !add_dynamic_entry (DT_RELASZ, 0)
1541 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela)))
1542 return false;
1543
1544 /* If any dynamic relocs apply to a read-only section,
1545 then we need a DT_TEXTREL entry. */
1546 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, (PTR) info);
1547
1548 if ((info->flags & DF_TEXTREL) != 0)
1549 {
1550 if (!add_dynamic_entry (DT_TEXTREL, 0))
1551 return false;
1552 }
1553 }
1554 }
1555 #undef add_dynamic_entry
1556
1557 return true;
1558 }
1559
1560 /* Relocate a 390 ELF section. */
1561
1562 static boolean
1563 elf_s390_relocate_section (output_bfd, info, input_bfd, input_section,
1564 contents, relocs, local_syms, local_sections)
1565 bfd *output_bfd;
1566 struct bfd_link_info *info;
1567 bfd *input_bfd;
1568 asection *input_section;
1569 bfd_byte *contents;
1570 Elf_Internal_Rela *relocs;
1571 Elf_Internal_Sym *local_syms;
1572 asection **local_sections;
1573 {
1574 struct elf_s390_link_hash_table *htab;
1575 Elf_Internal_Shdr *symtab_hdr;
1576 struct elf_link_hash_entry **sym_hashes;
1577 bfd_vma *local_got_offsets;
1578 Elf_Internal_Rela *rel;
1579 Elf_Internal_Rela *relend;
1580
1581 htab = elf_s390_hash_table (info);
1582 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1583 sym_hashes = elf_sym_hashes (input_bfd);
1584 local_got_offsets = elf_local_got_offsets (input_bfd);
1585
1586 rel = relocs;
1587 relend = relocs + input_section->reloc_count;
1588 for (; rel < relend; rel++)
1589 {
1590 int r_type;
1591 reloc_howto_type *howto;
1592 unsigned long r_symndx;
1593 struct elf_link_hash_entry *h;
1594 Elf_Internal_Sym *sym;
1595 asection *sec;
1596 bfd_vma off;
1597 bfd_vma relocation;
1598 boolean unresolved_reloc;
1599 bfd_reloc_status_type r;
1600
1601 r_type = ELF64_R_TYPE (rel->r_info);
1602 if (r_type == (int) R_390_GNU_VTINHERIT
1603 || r_type == (int) R_390_GNU_VTENTRY)
1604 continue;
1605 if (r_type < 0 || r_type >= (int) R_390_max)
1606 {
1607 bfd_set_error (bfd_error_bad_value);
1608 return false;
1609 }
1610 howto = elf_howto_table + r_type;
1611
1612 r_symndx = ELF64_R_SYM (rel->r_info);
1613
1614 if (info->relocateable)
1615 {
1616 /* This is a relocateable link. We don't have to change
1617 anything, unless the reloc is against a section symbol,
1618 in which case we have to adjust according to where the
1619 section symbol winds up in the output section. */
1620 if (r_symndx < symtab_hdr->sh_info)
1621 {
1622 sym = local_syms + r_symndx;
1623 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1624 {
1625 sec = local_sections[r_symndx];
1626 rel->r_addend += sec->output_offset + sym->st_value;
1627 }
1628 }
1629
1630 continue;
1631 }
1632
1633 /* This is a final link. */
1634 h = NULL;
1635 sym = NULL;
1636 sec = NULL;
1637 unresolved_reloc = false;
1638 if (r_symndx < symtab_hdr->sh_info)
1639 {
1640 sym = local_syms + r_symndx;
1641 sec = local_sections[r_symndx];
1642 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, sec, rel);
1643 }
1644 else
1645 {
1646 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1647 while (h->root.type == bfd_link_hash_indirect
1648 || h->root.type == bfd_link_hash_warning)
1649 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1650
1651 if (h->root.type == bfd_link_hash_defined
1652 || h->root.type == bfd_link_hash_defweak)
1653 {
1654 sec = h->root.u.def.section;
1655 if (sec->output_section == NULL)
1656 {
1657 /* Set a flag that will be cleared later if we find a
1658 relocation value for this symbol. output_section
1659 is typically NULL for symbols satisfied by a shared
1660 library. */
1661 unresolved_reloc = true;
1662 relocation = 0;
1663 }
1664 else
1665 relocation = (h->root.u.def.value
1666 + sec->output_section->vma
1667 + sec->output_offset);
1668 }
1669 else if (h->root.type == bfd_link_hash_undefweak)
1670 relocation = 0;
1671 else if (info->shared
1672 && (!info->symbolic || info->allow_shlib_undefined)
1673 && !info->no_undefined
1674 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1675 relocation = 0;
1676 else
1677 {
1678 if (! ((*info->callbacks->undefined_symbol)
1679 (info, h->root.root.string, input_bfd,
1680 input_section, rel->r_offset,
1681 (!info->shared || info->no_undefined
1682 || ELF_ST_VISIBILITY (h->other)))))
1683 return false;
1684 relocation = 0;
1685 }
1686 }
1687
1688 switch (r_type)
1689 {
1690 case R_390_GOT12:
1691 case R_390_GOT16:
1692 case R_390_GOT32:
1693 case R_390_GOT64:
1694 case R_390_GOTENT:
1695 /* Relocation is to the entry for this symbol in the global
1696 offset table. */
1697 if (htab->sgot == NULL)
1698 abort ();
1699
1700 if (h != NULL)
1701 {
1702 boolean dyn;
1703
1704 off = h->got.offset;
1705 dyn = htab->elf.dynamic_sections_created;
1706 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)
1707 || (info->shared
1708 && (info->symbolic
1709 || h->dynindx == -1
1710 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
1711 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1712 {
1713 /* This is actually a static link, or it is a
1714 -Bsymbolic link and the symbol is defined
1715 locally, or the symbol was forced to be local
1716 because of a version file. We must initialize
1717 this entry in the global offset table. Since the
1718 offset must always be a multiple of 2, we use the
1719 least significant bit to record whether we have
1720 initialized it already.
1721
1722 When doing a dynamic link, we create a .rel.got
1723 relocation entry to initialize the value. This
1724 is done in the finish_dynamic_symbol routine. */
1725 if ((off & 1) != 0)
1726 off &= ~1;
1727 else
1728 {
1729 bfd_put_64 (output_bfd, relocation,
1730 htab->sgot->contents + off);
1731 h->got.offset |= 1;
1732 }
1733 }
1734 else
1735 unresolved_reloc = false;
1736 }
1737 else
1738 {
1739 if (local_got_offsets == NULL)
1740 abort ();
1741
1742 off = local_got_offsets[r_symndx];
1743
1744 /* The offset must always be a multiple of 8. We use
1745 the least significant bit to record whether we have
1746 already generated the necessary reloc. */
1747 if ((off & 1) != 0)
1748 off &= ~1;
1749 else
1750 {
1751 bfd_put_64 (output_bfd, relocation,
1752 htab->sgot->contents + off);
1753
1754 if (info->shared)
1755 {
1756 asection *srelgot;
1757 Elf_Internal_Rela outrel;
1758 Elf64_External_Rela *loc;
1759
1760 srelgot = htab->srelgot;
1761 if (srelgot == NULL)
1762 abort ();
1763
1764 outrel.r_offset = (htab->sgot->output_section->vma
1765 + htab->sgot->output_offset
1766 + off);
1767 outrel.r_info = ELF64_R_INFO (0, R_390_RELATIVE);
1768 outrel.r_addend = relocation;
1769 loc = (Elf64_External_Rela *) srelgot->contents;
1770 loc += srelgot->reloc_count++;
1771 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1772 }
1773
1774 local_got_offsets[r_symndx] |= 1;
1775 }
1776 }
1777
1778 if (off >= (bfd_vma) -2)
1779 abort ();
1780
1781 relocation = htab->sgot->output_offset + off;
1782
1783 /*
1784 * For @GOTENT the relocation is against the offset between
1785 * the instruction and the symbols entry in the GOT and not
1786 * between the start of the GOT and the symbols entry. We
1787 * add the vma of the GOT to get the correct value.
1788 */
1789 if (r_type == R_390_GOTENT)
1790 relocation += htab->sgot->output_section->vma;
1791
1792 break;
1793
1794 case R_390_GOTOFF:
1795 /* Relocation is relative to the start of the global offset
1796 table. */
1797
1798 /* Note that sgot->output_offset is not involved in this
1799 calculation. We always want the start of .got. If we
1800 defined _GLOBAL_OFFSET_TABLE in a different way, as is
1801 permitted by the ABI, we might have to change this
1802 calculation. */
1803 relocation -= htab->sgot->output_section->vma;
1804
1805 break;
1806
1807 case R_390_GOTPC:
1808 case R_390_GOTPCDBL:
1809 /* Use global offset table as symbol value. */
1810 relocation = htab->sgot->output_section->vma;
1811 unresolved_reloc = false;
1812 break;
1813
1814 case R_390_PLT16DBL:
1815 case R_390_PLT32:
1816 case R_390_PLT32DBL:
1817 case R_390_PLT64:
1818 /* Relocation is to the entry for this symbol in the
1819 procedure linkage table. */
1820
1821 /* Resolve a PLT32 reloc against a local symbol directly,
1822 without using the procedure linkage table. */
1823 if (h == NULL)
1824 break;
1825
1826 if (h->plt.offset == (bfd_vma) -1
1827 || htab->splt == NULL)
1828 {
1829 /* We didn't make a PLT entry for this symbol. This
1830 happens when statically linking PIC code, or when
1831 using -Bsymbolic. */
1832 break;
1833 }
1834
1835 relocation = (htab->splt->output_section->vma
1836 + htab->splt->output_offset
1837 + h->plt.offset);
1838 unresolved_reloc = false;
1839 break;
1840
1841 case R_390_8:
1842 case R_390_16:
1843 case R_390_32:
1844 case R_390_64:
1845 case R_390_PC16:
1846 case R_390_PC16DBL:
1847 case R_390_PC32:
1848 case R_390_PC32DBL:
1849 case R_390_PC64:
1850 /* r_symndx will be zero only for relocs against symbols
1851 from removed linkonce sections, or sections discarded by
1852 a linker script. */
1853 if (r_symndx == 0
1854 || (input_section->flags & SEC_ALLOC) == 0)
1855 break;
1856
1857 if ((info->shared
1858 && ((r_type != R_390_PC16
1859 && r_type != R_390_PC16DBL
1860 && r_type != R_390_PC32
1861 && r_type != R_390_PC32DBL
1862 && r_type != R_390_PC64)
1863 || (h != NULL
1864 && h->dynindx != -1
1865 && (! info->symbolic
1866 || (h->elf_link_hash_flags
1867 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1868 || (!info->shared
1869 && h != NULL
1870 && h->dynindx != -1
1871 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1872 && (((h->elf_link_hash_flags
1873 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1874 && (h->elf_link_hash_flags
1875 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1876 || h->root.type == bfd_link_hash_undefweak
1877 || h->root.type == bfd_link_hash_undefined)))
1878 {
1879 Elf_Internal_Rela outrel;
1880 boolean skip, relocate;
1881 asection *sreloc;
1882 Elf64_External_Rela *loc;
1883
1884 /* When generating a shared object, these relocations
1885 are copied into the output file to be resolved at run
1886 time. */
1887
1888 skip = false;
1889
1890 outrel.r_offset =
1891 _bfd_elf_section_offset (output_bfd, info, input_section,
1892 rel->r_offset);
1893 if (outrel.r_offset == (bfd_vma) -1)
1894 skip = true;
1895
1896 outrel.r_offset += (input_section->output_section->vma
1897 + input_section->output_offset);
1898
1899 if (skip)
1900 {
1901 memset (&outrel, 0, sizeof outrel);
1902 relocate = false;
1903 }
1904 else if (h != NULL
1905 && h->dynindx != -1
1906 && (r_type == R_390_PC16
1907 || r_type == R_390_PC16DBL
1908 || r_type == R_390_PC32
1909 || r_type == R_390_PC32DBL
1910 || r_type == R_390_PC64
1911 || !info->shared
1912 || !info->symbolic
1913 || (h->elf_link_hash_flags
1914 & ELF_LINK_HASH_DEF_REGULAR) == 0))
1915 {
1916 relocate = false;
1917 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
1918 outrel.r_addend = rel->r_addend;
1919 }
1920 else
1921 {
1922 /* This symbol is local, or marked to become local. */
1923 relocate = true;
1924 outrel.r_info = ELF64_R_INFO (0, R_390_RELATIVE);
1925 outrel.r_addend = relocation + rel->r_addend;
1926 }
1927
1928 sreloc = elf_section_data (input_section)->sreloc;
1929 if (sreloc == NULL)
1930 abort ();
1931
1932 loc = (Elf64_External_Rela *) sreloc->contents;
1933 loc += sreloc->reloc_count++;
1934 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc);
1935
1936 /* If this reloc is against an external symbol, we do
1937 not want to fiddle with the addend. Otherwise, we
1938 need to include the symbol value so that it becomes
1939 an addend for the dynamic reloc. */
1940 if (! relocate)
1941 continue;
1942 }
1943
1944 break;
1945
1946 default:
1947 break;
1948 }
1949
1950 if (unresolved_reloc
1951 && !(info->shared
1952 && (input_section->flags & SEC_DEBUGGING) != 0
1953 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
1954 (*_bfd_error_handler)
1955 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
1956 bfd_archive_filename (input_bfd),
1957 bfd_get_section_name (input_bfd, input_section),
1958 (long) rel->r_offset,
1959 h->root.root.string);
1960
1961 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1962 contents, rel->r_offset,
1963 relocation, rel->r_addend);
1964
1965 if (r != bfd_reloc_ok)
1966 {
1967 const char *name;
1968
1969 if (h != NULL)
1970 name = h->root.root.string;
1971 else
1972 {
1973 name = bfd_elf_string_from_elf_section (input_bfd,
1974 symtab_hdr->sh_link,
1975 sym->st_name);
1976 if (name == NULL)
1977 return false;
1978 if (*name == '\0')
1979 name = bfd_section_name (input_bfd, sec);
1980 }
1981
1982 if (r == bfd_reloc_overflow)
1983 {
1984
1985 if (! ((*info->callbacks->reloc_overflow)
1986 (info, name, howto->name, (bfd_vma) 0,
1987 input_bfd, input_section, rel->r_offset)))
1988 return false;
1989 }
1990 else
1991 {
1992 (*_bfd_error_handler)
1993 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
1994 bfd_archive_filename (input_bfd),
1995 bfd_get_section_name (input_bfd, input_section),
1996 (long) rel->r_offset, name, (int) r);
1997 return false;
1998 }
1999 }
2000 }
2001
2002 return true;
2003 }
2004
2005 /* Finish up dynamic symbol handling. We set the contents of various
2006 dynamic sections here. */
2007
2008 static boolean
2009 elf_s390_finish_dynamic_symbol (output_bfd, info, h, sym)
2010 bfd *output_bfd;
2011 struct bfd_link_info *info;
2012 struct elf_link_hash_entry *h;
2013 Elf_Internal_Sym *sym;
2014 {
2015 struct elf_s390_link_hash_table *htab;
2016
2017 htab = elf_s390_hash_table (info);
2018
2019 if (h->plt.offset != (bfd_vma) -1)
2020 {
2021 bfd_vma plt_index;
2022 bfd_vma got_offset;
2023 Elf_Internal_Rela rela;
2024 Elf64_External_Rela *loc;
2025
2026 /* This symbol has an entry in the procedure linkage table. Set
2027 it up. */
2028
2029 if (h->dynindx == -1
2030 || htab->splt == NULL
2031 || htab->sgotplt == NULL
2032 || htab->srelplt == NULL)
2033 abort ();
2034
2035 /* Calc. index no.
2036 Current offset - size first entry / entry size. */
2037 plt_index = (h->plt.offset - PLT_FIRST_ENTRY_SIZE) / PLT_ENTRY_SIZE;
2038
2039 /* Offset in GOT is PLT index plus GOT headers(3) times 8,
2040 addr & GOT addr. */
2041 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
2042
2043 /* Fill in the blueprint of a PLT. */
2044 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD0,
2045 htab->splt->contents + h->plt.offset);
2046 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD1,
2047 htab->splt->contents + h->plt.offset + 4);
2048 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD2,
2049 htab->splt->contents + h->plt.offset + 8);
2050 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD3,
2051 htab->splt->contents + h->plt.offset + 12);
2052 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD4,
2053 htab->splt->contents + h->plt.offset + 16);
2054 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD5,
2055 htab->splt->contents + h->plt.offset + 20);
2056 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD6,
2057 htab->splt->contents + h->plt.offset + 24);
2058 bfd_put_32 (output_bfd, (bfd_vma) PLT_ENTRY_WORD7,
2059 htab->splt->contents + h->plt.offset + 28);
2060 /* Fixup the relative address to the GOT entry */
2061 bfd_put_32 (output_bfd,
2062 (htab->sgotplt->output_section->vma +
2063 htab->sgotplt->output_offset + got_offset
2064 - (htab->splt->output_section->vma + h->plt.offset))/2,
2065 htab->splt->contents + h->plt.offset + 2);
2066 /* Fixup the relative branch to PLT 0 */
2067 bfd_put_32 (output_bfd, - (PLT_FIRST_ENTRY_SIZE +
2068 (PLT_ENTRY_SIZE * plt_index) + 22)/2,
2069 htab->splt->contents + h->plt.offset + 24);
2070 /* Fixup offset into symbol table */
2071 bfd_put_32 (output_bfd, plt_index * sizeof (Elf64_External_Rela),
2072 htab->splt->contents + h->plt.offset + 28);
2073
2074 /* Fill in the entry in the global offset table.
2075 Points to instruction after GOT offset. */
2076 bfd_put_64 (output_bfd,
2077 (htab->splt->output_section->vma
2078 + htab->splt->output_offset
2079 + h->plt.offset
2080 + 14),
2081 htab->sgotplt->contents + got_offset);
2082
2083 /* Fill in the entry in the .rela.plt section. */
2084 rela.r_offset = (htab->sgotplt->output_section->vma
2085 + htab->sgotplt->output_offset
2086 + got_offset);
2087 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_JMP_SLOT);
2088 rela.r_addend = 0;
2089 loc = (Elf64_External_Rela *) htab->srelplt->contents + plt_index;
2090 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2091
2092 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2093 {
2094 /* Mark the symbol as undefined, rather than as defined in
2095 the .plt section. Leave the value alone. This is a clue
2096 for the dynamic linker, to make function pointer
2097 comparisons work between an application and shared
2098 library. */
2099 sym->st_shndx = SHN_UNDEF;
2100 }
2101 }
2102
2103 if (h->got.offset != (bfd_vma) -1)
2104 {
2105 Elf_Internal_Rela rela;
2106 Elf64_External_Rela *loc;
2107
2108 /* This symbol has an entry in the global offset table. Set it
2109 up. */
2110
2111 if (htab->sgot == NULL || htab->srelgot == NULL)
2112 abort ();
2113
2114 rela.r_offset = (htab->sgot->output_section->vma
2115 + htab->sgot->output_offset
2116 + (h->got.offset &~ (bfd_vma) 1));
2117
2118 /* If this is a static link, or it is a -Bsymbolic link and the
2119 symbol is defined locally or was forced to be local because
2120 of a version file, we just want to emit a RELATIVE reloc.
2121 The entry in the global offset table will already have been
2122 initialized in the relocate_section function. */
2123 if (info->shared
2124 && (info->symbolic
2125 || h->dynindx == -1
2126 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
2127 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
2128 {
2129 BFD_ASSERT((h->got.offset & 1) != 0);
2130 rela.r_info = ELF64_R_INFO (0, R_390_RELATIVE);
2131 rela.r_addend = (h->root.u.def.value
2132 + h->root.u.def.section->output_section->vma
2133 + h->root.u.def.section->output_offset);
2134 }
2135 else
2136 {
2137 BFD_ASSERT((h->got.offset & 1) == 0);
2138 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgot->contents + h->got.offset);
2139 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_GLOB_DAT);
2140 rela.r_addend = 0;
2141 }
2142
2143 loc = (Elf64_External_Rela *) htab->srelgot->contents;
2144 loc += htab->srelgot->reloc_count++;
2145 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2146 }
2147
2148 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2149 {
2150 Elf_Internal_Rela rela;
2151 Elf64_External_Rela *loc;
2152
2153 /* This symbols needs a copy reloc. Set it up. */
2154
2155 if (h->dynindx == -1
2156 || (h->root.type != bfd_link_hash_defined
2157 && h->root.type != bfd_link_hash_defweak)
2158 || htab->srelbss == NULL)
2159 abort ();
2160
2161 rela.r_offset = (h->root.u.def.value
2162 + h->root.u.def.section->output_section->vma
2163 + h->root.u.def.section->output_offset);
2164 rela.r_info = ELF64_R_INFO (h->dynindx, R_390_COPY);
2165 rela.r_addend = 0;
2166 loc = (Elf64_External_Rela *) htab->srelbss->contents;
2167 loc += htab->srelbss->reloc_count++;
2168 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
2169 }
2170
2171 /* Mark some specially defined symbols as absolute. */
2172 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2173 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0
2174 || strcmp (h->root.root.string, "_PROCEDURE_LINKAGE_TABLE_") == 0)
2175 sym->st_shndx = SHN_ABS;
2176
2177 return true;
2178 }
2179
2180 /* Used to decide how to sort relocs in an optimal manner for the
2181 dynamic linker, before writing them out. */
2182
2183 static enum elf_reloc_type_class
2184 elf_s390_reloc_type_class (rela)
2185 const Elf_Internal_Rela *rela;
2186 {
2187 switch ((int) ELF64_R_TYPE (rela->r_info))
2188 {
2189 case R_390_RELATIVE:
2190 return reloc_class_relative;
2191 case R_390_JMP_SLOT:
2192 return reloc_class_plt;
2193 case R_390_COPY:
2194 return reloc_class_copy;
2195 default:
2196 return reloc_class_normal;
2197 }
2198 }
2199
2200 /* Finish up the dynamic sections. */
2201
2202 static boolean
2203 elf_s390_finish_dynamic_sections (output_bfd, info)
2204 bfd *output_bfd;
2205 struct bfd_link_info *info;
2206 {
2207 struct elf_s390_link_hash_table *htab;
2208 bfd *dynobj;
2209 asection *sdyn;
2210
2211 htab = elf_s390_hash_table (info);
2212 dynobj = htab->elf.dynobj;
2213 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2214
2215 if (htab->elf.dynamic_sections_created)
2216 {
2217 Elf64_External_Dyn *dyncon, *dynconend;
2218
2219 if (sdyn == NULL || htab->sgot == NULL)
2220 abort ();
2221
2222 dyncon = (Elf64_External_Dyn *) sdyn->contents;
2223 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2224 for (; dyncon < dynconend; dyncon++)
2225 {
2226 Elf_Internal_Dyn dyn;
2227 asection *s;
2228
2229 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn);
2230
2231 switch (dyn.d_tag)
2232 {
2233 default:
2234 continue;
2235
2236 case DT_PLTGOT:
2237 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2238 break;
2239
2240 case DT_JMPREL:
2241 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2242 break;
2243
2244 case DT_PLTRELSZ:
2245 s = htab->srelplt->output_section;
2246 if (s->_cooked_size != 0)
2247 dyn.d_un.d_val = s->_cooked_size;
2248 else
2249 dyn.d_un.d_val = s->_raw_size;
2250 break;
2251
2252 case DT_RELASZ:
2253 /* The procedure linkage table relocs (DT_JMPREL) should
2254 not be included in the overall relocs (DT_RELA).
2255 Therefore, we override the DT_RELASZ entry here to
2256 make it not include the JMPREL relocs. Since the
2257 linker script arranges for .rela.plt to follow all
2258 other relocation sections, we don't have to worry
2259 about changing the DT_RELA entry. */
2260 s = htab->srelplt->output_section;
2261 if (s->_cooked_size != 0)
2262 dyn.d_un.d_val -= s->_cooked_size;
2263 else
2264 dyn.d_un.d_val -= s->_raw_size;
2265 break;
2266 }
2267
2268 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon);
2269 }
2270
2271 /* Fill in the special first entry in the procedure linkage table. */
2272 if (htab->splt && htab->splt->_raw_size > 0)
2273 {
2274 /* fill in blueprint for plt 0 entry */
2275 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD0,
2276 htab->splt->contents );
2277 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD1,
2278 htab->splt->contents +4 );
2279 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD3,
2280 htab->splt->contents +12 );
2281 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD4,
2282 htab->splt->contents +16 );
2283 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD5,
2284 htab->splt->contents +20 );
2285 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD6,
2286 htab->splt->contents + 24);
2287 bfd_put_32 (output_bfd, (bfd_vma) PLT_FIRST_ENTRY_WORD7,
2288 htab->splt->contents + 28 );
2289 /* Fixup relative address to start of GOT */
2290 bfd_put_32 (output_bfd,
2291 (htab->sgotplt->output_section->vma +
2292 htab->sgotplt->output_offset
2293 - htab->splt->output_section->vma - 6)/2,
2294 htab->splt->contents + 8);
2295 }
2296 elf_section_data (htab->splt->output_section)
2297 ->this_hdr.sh_entsize = PLT_ENTRY_SIZE;
2298 }
2299
2300 if (htab->sgotplt)
2301 {
2302 /* Fill in the first three entries in the global offset table. */
2303 if (htab->sgotplt->_raw_size > 0)
2304 {
2305 bfd_put_64 (output_bfd,
2306 (sdyn == NULL ? (bfd_vma) 0
2307 : sdyn->output_section->vma + sdyn->output_offset),
2308 htab->sgotplt->contents);
2309 /* One entry for shared object struct ptr. */
2310 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 8);
2311 /* One entry for _dl_runtime_resolve. */
2312 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 12);
2313 }
2314
2315 elf_section_data (htab->sgot->output_section)
2316 ->this_hdr.sh_entsize = 8;
2317 }
2318 return true;
2319 }
2320
2321 static boolean
2322 elf_s390_object_p (abfd)
2323 bfd *abfd;
2324 {
2325 return bfd_default_set_arch_mach (abfd, bfd_arch_s390, bfd_mach_s390_esame);
2326 }
2327
2328 /*
2329 * Why was the hash table entry size definition changed from
2330 * ARCH_SIZE/8 to 4? This breaks the 64 bit dynamic linker and
2331 * this is the only reason for the s390_elf64_size_info structure.
2332 */
2333
2334 const struct elf_size_info s390_elf64_size_info =
2335 {
2336 sizeof (Elf64_External_Ehdr),
2337 sizeof (Elf64_External_Phdr),
2338 sizeof (Elf64_External_Shdr),
2339 sizeof (Elf64_External_Rel),
2340 sizeof (Elf64_External_Rela),
2341 sizeof (Elf64_External_Sym),
2342 sizeof (Elf64_External_Dyn),
2343 sizeof (Elf_External_Note),
2344 8, /* hash-table entry size */
2345 1, /* internal relocations per external relocations */
2346 64, /* arch_size */
2347 8, /* file_align */
2348 ELFCLASS64, EV_CURRENT,
2349 bfd_elf64_write_out_phdrs,
2350 bfd_elf64_write_shdrs_and_ehdr,
2351 bfd_elf64_write_relocs,
2352 bfd_elf64_swap_symbol_out,
2353 bfd_elf64_slurp_reloc_table,
2354 bfd_elf64_slurp_symbol_table,
2355 bfd_elf64_swap_dyn_in,
2356 bfd_elf64_swap_dyn_out,
2357 NULL,
2358 NULL,
2359 NULL,
2360 NULL
2361 };
2362
2363 #define TARGET_BIG_SYM bfd_elf64_s390_vec
2364 #define TARGET_BIG_NAME "elf64-s390"
2365 #define ELF_ARCH bfd_arch_s390
2366 #define ELF_MACHINE_CODE EM_S390
2367 #define ELF_MACHINE_ALT1 EM_S390_OLD
2368 #define ELF_MAXPAGESIZE 0x1000
2369
2370 #define elf_backend_size_info s390_elf64_size_info
2371
2372 #define elf_backend_can_gc_sections 1
2373 #define elf_backend_can_refcount 1
2374 #define elf_backend_want_got_plt 1
2375 #define elf_backend_plt_readonly 1
2376 #define elf_backend_want_plt_sym 0
2377 #define elf_backend_got_header_size 24
2378 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2379
2380 #define elf_info_to_howto elf_s390_info_to_howto
2381
2382 #define bfd_elf64_bfd_is_local_label_name elf_s390_is_local_label_name
2383 #define bfd_elf64_bfd_link_hash_table_create elf_s390_link_hash_table_create
2384 #define bfd_elf64_bfd_reloc_type_lookup elf_s390_reloc_type_lookup
2385
2386 #define elf_backend_adjust_dynamic_symbol elf_s390_adjust_dynamic_symbol
2387 #define elf_backend_check_relocs elf_s390_check_relocs
2388 #define elf_backend_copy_indirect_symbol elf_s390_copy_indirect_symbol
2389 #define elf_backend_create_dynamic_sections elf_s390_create_dynamic_sections
2390 #define elf_backend_finish_dynamic_sections elf_s390_finish_dynamic_sections
2391 #define elf_backend_finish_dynamic_symbol elf_s390_finish_dynamic_symbol
2392 #define elf_backend_gc_mark_hook elf_s390_gc_mark_hook
2393 #define elf_backend_gc_sweep_hook elf_s390_gc_sweep_hook
2394 #define elf_backend_reloc_type_class elf_s390_reloc_type_class
2395 #define elf_backend_relocate_section elf_s390_relocate_section
2396 #define elf_backend_size_dynamic_sections elf_s390_size_dynamic_sections
2397 #define elf_backend_reloc_type_class elf_s390_reloc_type_class
2398
2399 #define elf_backend_object_p elf_s390_object_p
2400
2401 #include "elf64-target.h"
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