1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
|
/* Machine-dependent ELF dynamic relocation inline functions.
PowerPC64 version.
Copyright 1995-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, see <https://www.gnu.org/licenses/>. */
#ifndef dl_machine_h
#define dl_machine_h
#define ELF_MACHINE_NAME "powerpc64"
#include <assert.h>
#include <sys/param.h>
#include <dl-tls.h>
#include <sysdep.h>
#include <hwcapinfo.h>
#include <cpu-features.c>
#include <dl-static-tls.h>
#include <dl-funcdesc.h>
#include <dl-machine-rel.h>
/* Translate a processor specific dynamic tag to the index
in l_info array. */
#define DT_PPC64(x) (DT_PPC64_##x - DT_LOPROC + DT_NUM)
#define ELF_MULT_MACHINES_SUPPORTED
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int
elf_machine_matches_host (const Elf64_Ehdr *ehdr)
{
/* Verify that the binary matches our ABI version. */
if ((ehdr->e_flags & EF_PPC64_ABI) != 0)
{
#if _CALL_ELF != 2
if ((ehdr->e_flags & EF_PPC64_ABI) != 1)
return 0;
#else
if ((ehdr->e_flags & EF_PPC64_ABI) != 2)
return 0;
#endif
}
return ehdr->e_machine == EM_PPC64;
}
/* Return nonzero iff ELF header is compatible with the running host,
but not this loader. */
static inline int
elf_host_tolerates_machine (const Elf64_Ehdr *ehdr)
{
return ehdr->e_machine == EM_PPC;
}
/* Return nonzero iff ELF header is compatible with the running host,
but not this loader. */
static inline int
elf_host_tolerates_class (const Elf64_Ehdr *ehdr)
{
return ehdr->e_ident[EI_CLASS] == ELFCLASS32;
}
/* Return the run-time load address of the shared object, assuming it
was originally linked at zero. */
static inline Elf64_Addr
elf_machine_load_address (void) __attribute__ ((const));
static inline Elf64_Addr
elf_machine_load_address (void)
{
Elf64_Addr ret;
/* The first entry in .got (and thus the first entry in .toc) is the
link-time TOC_base, ie. r2. So the difference between that and
the current r2 set by the kernel is how far the shared lib has
moved. */
asm ( " ld %0,-32768(2)\n"
" subf %0,%0,2\n"
: "=r" (ret));
return ret;
}
/* Return the link-time address of _DYNAMIC. */
static inline Elf64_Addr
elf_machine_dynamic (void)
{
Elf64_Addr runtime_dynamic;
/* It's easier to get the run-time address. */
asm ( " addis %0,2,_DYNAMIC@toc@ha\n"
" addi %0,%0,_DYNAMIC@toc@l\n"
: "=b" (runtime_dynamic));
/* Then subtract off the load address offset. */
return runtime_dynamic - elf_machine_load_address() ;
}
/* The PLT uses Elf64_Rela relocs. */
#define elf_machine_relplt elf_machine_rela
#ifdef HAVE_INLINED_SYSCALLS
/* We do not need _dl_starting_up. */
# define DL_STARTING_UP_DEF
#else
# define DL_STARTING_UP_DEF \
".LC__dl_starting_up:\n" \
" .tc __GI__dl_starting_up[TC],__GI__dl_starting_up\n"
#endif
/* Initial entry point code for the dynamic linker. The C function
`_dl_start' is the real entry point; its return value is the user
program's entry point. */
#define RTLD_START \
asm (".pushsection \".text\"\n" \
" .align 2\n" \
" " ENTRY_2(_start) "\n" \
BODY_PREFIX "_start:\n" \
" " LOCALENTRY(_start) "\n" \
/* We start with the following on the stack, from top: \
argc (4 bytes); \
arguments for program (terminated by NULL); \
environment variables (terminated by NULL); \
arguments for the program loader. */ \
" mr 3,1\n" \
" li 4,0\n" \
" stdu 4,-128(1)\n" \
/* Call _dl_start with one parameter pointing at argc. */ \
" bl " DOT_PREFIX "_dl_start\n" \
" nop\n" \
/* Transfer control to _dl_start_user! */ \
" b " DOT_PREFIX "_dl_start_user\n" \
".LT__start:\n" \
" .long 0\n" \
" .byte 0x00,0x0c,0x24,0x40,0x00,0x00,0x00,0x00\n" \
" .long .LT__start-" BODY_PREFIX "_start\n" \
" .short .LT__start_name_end-.LT__start_name_start\n" \
".LT__start_name_start:\n" \
" .ascii \"_start\"\n" \
".LT__start_name_end:\n" \
" .align 2\n" \
" " END_2(_start) "\n" \
" .pushsection \".toc\",\"aw\"\n" \
DL_STARTING_UP_DEF \
".LC__rtld_local:\n" \
" .tc _rtld_local[TC],_rtld_local\n" \
".LC__dl_argc:\n" \
" .tc _dl_argc[TC],_dl_argc\n" \
".LC__dl_argv:\n" \
" .tc __GI__dl_argv[TC],__GI__dl_argv\n" \
".LC__dl_fini:\n" \
" .tc _dl_fini[TC],_dl_fini\n" \
" .popsection\n" \
" " ENTRY_2(_dl_start_user) "\n" \
/* Now, we do our main work of calling initialisation procedures. \
The ELF ABI doesn't say anything about parameters for these, \
so we just pass argc, argv, and the environment. \
Changing these is strongly discouraged (not least because argc is \
passed by value!). */ \
BODY_PREFIX "_dl_start_user:\n" \
" " LOCALENTRY(_dl_start_user) "\n" \
/* the address of _start in r30. */ \
" mr 30,3\n" \
/* &_dl_argc in 29, &_dl_argv in 27, and _dl_loaded in 28. */ \
" ld 28,.LC__rtld_local@toc(2)\n" \
" ld 29,.LC__dl_argc@toc(2)\n" \
" ld 27,.LC__dl_argv@toc(2)\n" \
/* _dl_init (_dl_loaded, _dl_argc, _dl_argv, _dl_argv+_dl_argc+1). */ \
" ld 3,0(28)\n" \
" lwa 4,0(29)\n" \
" ld 5,0(27)\n" \
" sldi 6,4,3\n" \
" add 6,5,6\n" \
" addi 6,6,8\n" \
" bl " DOT_PREFIX "_dl_init\n" \
" nop\n" \
/* Now, to conform to the ELF ABI, we have to: \
Pass argc (actually _dl_argc) in r3; */ \
" lwa 3,0(29)\n" \
/* Pass argv (actually _dl_argv) in r4; */ \
" ld 4,0(27)\n" \
/* Pass argv+argc+1 in r5; */ \
" sldi 5,3,3\n" \
" add 6,4,5\n" \
" addi 5,6,8\n" \
/* Pass the auxiliary vector in r6. This is passed to us just after \
_envp. */ \
"2: ldu 0,8(6)\n" \
" cmpdi 0,0\n" \
" bne 2b\n" \
" addi 6,6,8\n" \
/* Pass a termination function pointer (in this case _dl_fini) in \
r7. */ \
" ld 7,.LC__dl_fini@toc(2)\n" \
/* Pass the stack pointer in r1 (so far so good), pointing to a NULL \
value. This lets our startup code distinguish between a program \
linked statically, which linux will call with argc on top of the \
stack which will hopefully never be zero, and a dynamically linked \
program which will always have a NULL on the top of the stack. \
Take the opportunity to clear LR, so anyone who accidentally \
returns from _start gets SEGV. Also clear the next few words of \
the stack. */ \
" li 31,0\n" \
" std 31,0(1)\n" \
" mtlr 31\n" \
" std 31,8(1)\n" \
" std 31,16(1)\n" \
" std 31,24(1)\n" \
/* Now, call the start function descriptor at r30... */ \
" .globl ._dl_main_dispatch\n" \
"._dl_main_dispatch:\n" \
" " PPC64_LOAD_FUNCPTR(30) "\n" \
" bctr\n" \
".LT__dl_start_user:\n" \
" .long 0\n" \
" .byte 0x00,0x0c,0x24,0x40,0x00,0x00,0x00,0x00\n" \
" .long .LT__dl_start_user-" BODY_PREFIX "_dl_start_user\n" \
" .short .LT__dl_start_user_name_end-.LT__dl_start_user_name_start\n" \
".LT__dl_start_user_name_start:\n" \
" .ascii \"_dl_start_user\"\n" \
".LT__dl_start_user_name_end:\n" \
" .align 2\n" \
" " END_2(_dl_start_user) "\n" \
" .popsection");
/* ELF_RTYPE_CLASS_COPY iff TYPE should not be allowed to resolve to
one of the main executable's symbols, as for a COPY reloc.
To make function pointer comparisons work on most targets, the
relevant ABI states that the address of a non-local function in a
dynamically linked executable is the address of the PLT entry for
that function. This is quite reasonable since using the real
function address in a non-PIC executable would typically require
dynamic relocations in .text, something to be avoided. For such
functions, the linker emits a SHN_UNDEF symbol in the executable
with value equal to the PLT entry address. Normally, SHN_UNDEF
symbols have a value of zero, so this is a clue to ld.so that it
should treat these symbols specially. For relocations not in
ELF_RTYPE_CLASS_PLT (eg. those on function pointers), ld.so should
use the value of the executable SHN_UNDEF symbol, ie. the PLT entry
address. For relocations in ELF_RTYPE_CLASS_PLT (eg. the relocs in
the PLT itself), ld.so should use the value of the corresponding
defined symbol in the object that defines the function, ie. the
real function address. This complicates ld.so in that there are
now two possible values for a given symbol, and it gets even worse
because protected symbols need yet another set of rules.
On PowerPC64 we don't need any of this. The linker won't emit
SHN_UNDEF symbols with non-zero values. ld.so can make all
relocations behave "normally", ie. always use the real address
like PLT relocations. So always set ELF_RTYPE_CLASS_PLT. */
#if _CALL_ELF != 2
#define elf_machine_type_class(type) \
(ELF_RTYPE_CLASS_PLT | (((type) == R_PPC64_COPY) * ELF_RTYPE_CLASS_COPY))
#else
/* And now that you have read that large comment, you can disregard it
all for ELFv2. ELFv2 does need the special SHN_UNDEF treatment. */
#define IS_PPC64_TLS_RELOC(R) \
(((R) >= R_PPC64_TLS && (R) <= R_PPC64_DTPREL16_HIGHESTA) \
|| ((R) >= R_PPC64_TPREL16_HIGH && (R) <= R_PPC64_DTPREL16_HIGHA))
#define elf_machine_type_class(type) \
((((type) == R_PPC64_JMP_SLOT \
|| (type) == R_PPC64_ADDR24 \
|| IS_PPC64_TLS_RELOC (type)) * ELF_RTYPE_CLASS_PLT) \
| (((type) == R_PPC64_COPY) * ELF_RTYPE_CLASS_COPY))
#endif
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_PPC64_JMP_SLOT
/* We define an initialization function to initialize HWCAP/HWCAP2 and
platform data so it can be copied into the TCB later. This is called
very early in _dl_sysdep_start for dynamically linked binaries. */
#if defined(SHARED) && IS_IN (rtld)
# define DL_PLATFORM_INIT dl_platform_init ()
static inline void __attribute__ ((unused))
dl_platform_init (void)
{
__tcb_parse_hwcap_and_convert_at_platform ();
init_cpu_features (&GLRO(dl_powerpc_cpu_features));
}
#endif
/* Stuff for the PLT. */
#if _CALL_ELF != 2
#define PLT_INITIAL_ENTRY_WORDS 3
#define PLT_ENTRY_WORDS 3
#define GLINK_INITIAL_ENTRY_WORDS 8
/* The first 32k entries of glink can set an index and branch using two
instructions; past that point, glink uses three instructions. */
#define GLINK_ENTRY_WORDS(I) (((I) < 0x8000)? 2 : 3)
#else
#define PLT_INITIAL_ENTRY_WORDS 2
#define PLT_ENTRY_WORDS 1
#define GLINK_INITIAL_ENTRY_WORDS 8
#define GLINK_ENTRY_WORDS(I) 1
#endif
#define PPC_DCBST(where) asm volatile ("dcbst 0,%0" : : "r"(where) : "memory")
#define PPC_DCBT(where) asm volatile ("dcbt 0,%0" : : "r"(where) : "memory")
#define PPC_DCBF(where) asm volatile ("dcbf 0,%0" : : "r"(where) : "memory")
#define PPC_SYNC asm volatile ("sync" : : : "memory")
#define PPC_ISYNC asm volatile ("sync; isync" : : : "memory")
#define PPC_ICBI(where) asm volatile ("icbi 0,%0" : : "r"(where) : "memory")
#define PPC_DIE asm volatile ("tweq 0,0")
/* Use this when you've modified some code, but it won't be in the
instruction fetch queue (or when it doesn't matter if it is). */
#define MODIFIED_CODE_NOQUEUE(where) \
do { PPC_DCBST(where); PPC_SYNC; PPC_ICBI(where); } while (0)
/* Use this when it might be in the instruction queue. */
#define MODIFIED_CODE(where) \
do { PPC_DCBST(where); PPC_SYNC; PPC_ICBI(where); PPC_ISYNC; } while (0)
/* Set up the loaded object described by MAP so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */
static inline int __attribute__ ((always_inline))
elf_machine_runtime_setup (struct link_map *map, struct r_scope_elem *scope[],
int lazy, int profile)
{
if (map->l_info[DT_JMPREL])
{
Elf64_Word i;
Elf64_Word *glink = NULL;
Elf64_Xword *plt = (Elf64_Xword *) D_PTR (map, l_info[DT_PLTGOT]);
Elf64_Word num_plt_entries = (map->l_info[DT_PLTRELSZ]->d_un.d_val
/ sizeof (Elf64_Rela));
Elf64_Addr l_addr = map->l_addr;
Elf64_Dyn **info = map->l_info;
char *p;
extern void _dl_runtime_resolve (void);
extern void _dl_profile_resolve (void);
/* Relocate the DT_PPC64_GLINK entry in the _DYNAMIC section.
elf_get_dynamic_info takes care of the standard entries but
doesn't know exactly what to do with processor specific
entries. */
if (info[DT_PPC64(GLINK)] != NULL)
info[DT_PPC64(GLINK)]->d_un.d_ptr += l_addr;
if (lazy)
{
Elf64_Word glink_offset;
Elf64_Word offset;
Elf64_Addr dlrr;
dlrr = (Elf64_Addr) (profile ? _dl_profile_resolve
: _dl_runtime_resolve);
if (profile && GLRO(dl_profile) != NULL
&& _dl_name_match_p (GLRO(dl_profile), map))
/* This is the object we are looking for. Say that we really
want profiling and the timers are started. */
GL(dl_profile_map) = map;
#if _CALL_ELF != 2
/* We need to stuff the address/TOC of _dl_runtime_resolve
into doublewords 0 and 1 of plt_reserve. Then we need to
stuff the map address into doubleword 2 of plt_reserve.
This allows the GLINK0 code to transfer control to the
correct trampoline which will transfer control to fixup
in dl-machine.c. */
{
/* The plt_reserve area is the 1st 3 doublewords of the PLT. */
Elf64_FuncDesc *plt_reserve = (Elf64_FuncDesc *) plt;
Elf64_FuncDesc *resolve_fd = (Elf64_FuncDesc *) dlrr;
plt_reserve->fd_func = resolve_fd->fd_func;
plt_reserve->fd_toc = resolve_fd->fd_toc;
plt_reserve->fd_aux = (Elf64_Addr) map;
#ifdef RTLD_BOOTSTRAP
/* When we're bootstrapping, the opd entry will not have
been relocated yet. */
plt_reserve->fd_func += l_addr;
plt_reserve->fd_toc += l_addr;
#endif
}
#else
/* When we don't have function descriptors, the first doubleword
of the PLT holds the address of _dl_runtime_resolve, and the
second doubleword holds the map address. */
plt[0] = dlrr;
plt[1] = (Elf64_Addr) map;
#endif
/* Set up the lazy PLT entries. */
glink = (Elf64_Word *) D_PTR (map, l_info[DT_PPC64(GLINK)]);
offset = PLT_INITIAL_ENTRY_WORDS;
glink_offset = GLINK_INITIAL_ENTRY_WORDS;
for (i = 0; i < num_plt_entries; i++)
{
plt[offset] = (Elf64_Xword) &glink[glink_offset];
offset += PLT_ENTRY_WORDS;
glink_offset += GLINK_ENTRY_WORDS (i);
}
/* Now, we've modified data. We need to write the changes from
the data cache to a second-level unified cache, then make
sure that stale data in the instruction cache is removed.
(In a multiprocessor system, the effect is more complex.)
Most of the PLT shouldn't be in the instruction cache, but
there may be a little overlap at the start and the end.
Assumes that dcbst and icbi apply to lines of 16 bytes or
more. Current known line sizes are 16, 32, and 128 bytes. */
for (p = (char *) plt; p < (char *) &plt[offset]; p += 16)
PPC_DCBST (p);
PPC_SYNC;
}
}
return lazy;
}
#if _CALL_ELF == 2
extern void attribute_hidden _dl_error_localentry (struct link_map *map,
const Elf64_Sym *refsym);
/* If the PLT entry resolves to a function in the same object, return
the target function's local entry point offset if usable. */
static inline Elf64_Addr __attribute__ ((always_inline))
ppc64_local_entry_offset (struct link_map *map, lookup_t sym_map,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym)
{
/* If the target function is in a different object, we cannot
use the local entry point. */
if (sym_map != map)
{
/* Check that optimized plt call stubs for localentry:0 functions
are not being satisfied by a non-zero localentry symbol. */
if (map->l_info[DT_PPC64(OPT)]
&& (map->l_info[DT_PPC64(OPT)]->d_un.d_val & PPC64_OPT_LOCALENTRY) != 0
&& refsym->st_info == ELFW(ST_INFO) (STB_GLOBAL, STT_FUNC)
&& (STO_PPC64_LOCAL_MASK & refsym->st_other) == 0
&& (STO_PPC64_LOCAL_MASK & sym->st_other) != 0)
_dl_error_localentry (map, refsym);
return 0;
}
/* If the linker inserted multiple TOCs, we cannot use the
local entry point. */
if (map->l_info[DT_PPC64(OPT)]
&& (map->l_info[DT_PPC64(OPT)]->d_un.d_val & PPC64_OPT_MULTI_TOC))
return 0;
/* If the target function is an ifunc then the local entry offset is
for the resolver, not the final destination. */
if (__builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0))
return 0;
/* Otherwise, we can use the local entry point. Retrieve its offset
from the symbol's ELF st_other field. */
return PPC64_LOCAL_ENTRY_OFFSET (sym->st_other);
}
#endif
/* Change the PLT entry whose reloc is 'reloc' to call the actual
routine. */
static inline Elf64_Addr __attribute__ ((always_inline))
elf_machine_fixup_plt (struct link_map *map, lookup_t sym_map,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const Elf64_Rela *reloc,
Elf64_Addr *reloc_addr, Elf64_Addr finaladdr)
{
#if _CALL_ELF != 2
Elf64_FuncDesc *plt = (Elf64_FuncDesc *) reloc_addr;
Elf64_FuncDesc *rel = (Elf64_FuncDesc *) finaladdr;
Elf64_Addr offset = 0;
Elf64_FuncDesc zero_fd = {0, 0, 0};
PPC_DCBT (&plt->fd_aux);
PPC_DCBT (&plt->fd_func);
/* If sym_map is NULL, it's a weak undefined sym; Set the plt to
zero. finaladdr should be zero already in this case, but guard
against invalid plt relocations with non-zero addends. */
if (sym_map == NULL)
finaladdr = 0;
/* Don't die here if finaladdr is zero, die if this plt entry is
actually called. Makes a difference when LD_BIND_NOW=1.
finaladdr may be zero for a weak undefined symbol, or when an
ifunc resolver returns zero. */
if (finaladdr == 0)
rel = &zero_fd;
else
{
PPC_DCBT (&rel->fd_aux);
PPC_DCBT (&rel->fd_func);
}
/* If the opd entry is not yet relocated (because it's from a shared
object that hasn't been processed yet), then manually reloc it. */
if (finaladdr != 0 && map != sym_map && !sym_map->l_relocated
#if !defined RTLD_BOOTSTRAP && defined SHARED
/* Bootstrap map doesn't have l_relocated set for it. */
&& sym_map != &GL(dl_rtld_map)
#endif
)
offset = sym_map->l_addr;
/* For PPC64, fixup_plt copies the function descriptor from opd
over the corresponding PLT entry.
Initially, PLT Entry[i] is set up for lazy linking, or is zero.
For lazy linking, the fd_toc and fd_aux entries are irrelevant,
so for thread safety we write them before changing fd_func. */
plt->fd_aux = rel->fd_aux + offset;
plt->fd_toc = rel->fd_toc + offset;
PPC_DCBF (&plt->fd_toc);
PPC_ISYNC;
plt->fd_func = rel->fd_func + offset;
PPC_DCBST (&plt->fd_func);
PPC_ISYNC;
#else
finaladdr += ppc64_local_entry_offset (map, sym_map, refsym, sym);
*reloc_addr = finaladdr;
#endif
return finaladdr;
}
static inline void __attribute__ ((always_inline))
elf_machine_plt_conflict (struct link_map *map, lookup_t sym_map,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const Elf64_Rela *reloc,
Elf64_Addr *reloc_addr, Elf64_Addr finaladdr)
{
#if _CALL_ELF != 2
Elf64_FuncDesc *plt = (Elf64_FuncDesc *) reloc_addr;
Elf64_FuncDesc *rel = (Elf64_FuncDesc *) finaladdr;
Elf64_FuncDesc zero_fd = {0, 0, 0};
if (sym_map == NULL)
finaladdr = 0;
if (finaladdr == 0)
rel = &zero_fd;
plt->fd_func = rel->fd_func;
plt->fd_aux = rel->fd_aux;
plt->fd_toc = rel->fd_toc;
PPC_DCBST (&plt->fd_func);
PPC_DCBST (&plt->fd_aux);
PPC_DCBST (&plt->fd_toc);
PPC_SYNC;
#else
finaladdr += ppc64_local_entry_offset (map, sym_map, refsym, sym);
*reloc_addr = finaladdr;
#endif
}
/* Return the final value of a plt relocation. */
static inline Elf64_Addr
elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
Elf64_Addr value)
{
return value + reloc->r_addend;
}
/* Names of the architecture-specific auditing callback functions. */
#if _CALL_ELF != 2
#define ARCH_LA_PLTENTER ppc64_gnu_pltenter
#define ARCH_LA_PLTEXIT ppc64_gnu_pltexit
#else
#define ARCH_LA_PLTENTER ppc64v2_gnu_pltenter
#define ARCH_LA_PLTEXIT ppc64v2_gnu_pltexit
#endif
#endif /* dl_machine_h */
#ifdef RESOLVE_MAP
#define PPC_LO(v) ((v) & 0xffff)
#define PPC_HI(v) (((v) >> 16) & 0xffff)
#define PPC_HA(v) PPC_HI ((v) + 0x8000)
#define PPC_HIGHER(v) (((v) >> 32) & 0xffff)
#define PPC_HIGHERA(v) PPC_HIGHER ((v) + 0x8000)
#define PPC_HIGHEST(v) (((v) >> 48) & 0xffff)
#define PPC_HIGHESTA(v) PPC_HIGHEST ((v) + 0x8000)
#define BIT_INSERT(var, val, mask) \
((var) = ((var) & ~(Elf64_Addr) (mask)) | ((val) & (mask)))
#define dont_expect(X) __builtin_expect ((X), 0)
extern void attribute_hidden _dl_reloc_overflow (struct link_map *map,
const char *name,
Elf64_Addr *const reloc_addr,
const Elf64_Sym *refsym);
static inline void __attribute__ ((always_inline))
elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc,
void *const reloc_addr_arg)
{
Elf64_Addr *const reloc_addr = reloc_addr_arg;
*reloc_addr = l_addr + reloc->r_addend;
}
/* This computes the value used by TPREL* relocs. */
static inline Elf64_Addr __attribute__ ((always_inline, const))
elf_machine_tprel (struct link_map *map,
struct link_map *sym_map,
const Elf64_Sym *sym,
const Elf64_Rela *reloc)
{
#ifndef RTLD_BOOTSTRAP
if (sym_map)
{
CHECK_STATIC_TLS (map, sym_map);
#endif
return TLS_TPREL_VALUE (sym_map, sym, reloc);
#ifndef RTLD_BOOTSTRAP
}
#endif
return 0;
}
/* Call function at address VALUE (an OPD entry) to resolve ifunc relocs. */
static inline Elf64_Addr __attribute__ ((always_inline))
resolve_ifunc (Elf64_Addr value,
const struct link_map *map, const struct link_map *sym_map)
{
#if _CALL_ELF != 2
#ifndef RESOLVE_CONFLICT_FIND_MAP
/* The function we are calling may not yet have its opd entry relocated. */
Elf64_FuncDesc opd;
if (map != sym_map
# if !defined RTLD_BOOTSTRAP && defined SHARED
/* Bootstrap map doesn't have l_relocated set for it. */
&& sym_map != &GL(dl_rtld_map)
# endif
&& !sym_map->l_relocated)
{
Elf64_FuncDesc *func = (Elf64_FuncDesc *) value;
opd.fd_func = func->fd_func + sym_map->l_addr;
opd.fd_toc = func->fd_toc + sym_map->l_addr;
opd.fd_aux = func->fd_aux;
/* GCC 4.9+ eliminates the branch as dead code, force the odp set
dependency. */
asm ("" : "=r" (value) : "0" (&opd), "X" (opd));
}
#endif
#endif
return ((Elf64_Addr (*) (unsigned long int)) value) (GLRO(dl_hwcap));
}
/* Perform the relocation specified by RELOC and SYM (which is fully
resolved). MAP is the object containing the reloc. */
static inline void __attribute__ ((always_inline))
elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
const Elf64_Rela *reloc,
const Elf64_Sym *sym,
const struct r_found_version *version,
void *const reloc_addr_arg,
int skip_ifunc)
{
Elf64_Addr *const reloc_addr = reloc_addr_arg;
const int r_type = ELF64_R_TYPE (reloc->r_info);
const Elf64_Sym *const refsym = sym;
union unaligned
{
uint16_t u2;
uint32_t u4;
uint64_t u8;
} __attribute__ ((__packed__));
if (r_type == R_PPC64_RELATIVE)
{
*reloc_addr = map->l_addr + reloc->r_addend;
return;
}
if (__glibc_unlikely (r_type == R_PPC64_NONE))
return;
/* We need SYM_MAP even in the absence of TLS, for elf_machine_fixup_plt
and STT_GNU_IFUNC. */
struct link_map *sym_map = RESOLVE_MAP (map, scope, &sym, version, r_type);
Elf64_Addr value = SYMBOL_ADDRESS (sym_map, sym, true) + reloc->r_addend;
if (sym != NULL
&& __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0)
&& __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
&& __builtin_expect (!skip_ifunc, 1))
value = resolve_ifunc (value, map, sym_map);
/* For relocs that don't edit code, return.
For relocs that might edit instructions, break from the switch. */
switch (r_type)
{
case R_PPC64_ADDR64:
case R_PPC64_GLOB_DAT:
*reloc_addr = value;
return;
case R_PPC64_IRELATIVE:
if (__glibc_likely (!skip_ifunc))
value = resolve_ifunc (value, map, sym_map);
*reloc_addr = value;
return;
case R_PPC64_JMP_IREL:
if (__glibc_likely (!skip_ifunc))
value = resolve_ifunc (value, map, sym_map);
/* Fall thru */
case R_PPC64_JMP_SLOT:
#ifdef RESOLVE_CONFLICT_FIND_MAP
elf_machine_plt_conflict (map, sym_map, refsym, sym,
reloc, reloc_addr, value);
#else
elf_machine_fixup_plt (map, sym_map, refsym, sym,
reloc, reloc_addr, value);
#endif
return;
case R_PPC64_DTPMOD64:
if (map->l_info[DT_PPC64(OPT)]
&& (map->l_info[DT_PPC64(OPT)]->d_un.d_val & PPC64_OPT_TLS))
{
#ifdef RTLD_BOOTSTRAP
reloc_addr[0] = 0;
reloc_addr[1] = (sym_map->l_tls_offset - TLS_TP_OFFSET
+ TLS_DTV_OFFSET);
return;
#else
if (sym_map != NULL)
{
# ifndef SHARED
CHECK_STATIC_TLS (map, sym_map);
# else
if (TRY_STATIC_TLS (map, sym_map))
# endif
{
reloc_addr[0] = 0;
/* Set up for local dynamic. */
reloc_addr[1] = (sym_map->l_tls_offset - TLS_TP_OFFSET
+ TLS_DTV_OFFSET);
return;
}
}
#endif
}
#ifdef RTLD_BOOTSTRAP
/* During startup the dynamic linker is always index 1. */
*reloc_addr = 1;
#else
/* Get the information from the link map returned by the
resolve function. */
if (sym_map != NULL)
*reloc_addr = sym_map->l_tls_modid;
#endif
return;
case R_PPC64_DTPREL64:
if (map->l_info[DT_PPC64(OPT)]
&& (map->l_info[DT_PPC64(OPT)]->d_un.d_val & PPC64_OPT_TLS))
{
#ifdef RTLD_BOOTSTRAP
*reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
return;
#else
if (sym_map != NULL)
{
/* This reloc is always preceded by R_PPC64_DTPMOD64. */
# ifndef SHARED
assert (HAVE_STATIC_TLS (map, sym_map));
# else
if (HAVE_STATIC_TLS (map, sym_map))
# endif
{
*reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
return;
}
}
#endif
}
/* During relocation all TLS symbols are defined and used.
Therefore the offset is already correct. */
#ifndef RTLD_BOOTSTRAP
if (sym_map != NULL)
*reloc_addr = TLS_DTPREL_VALUE (sym, reloc);
#endif
return;
case R_PPC64_TPREL64:
*reloc_addr = elf_machine_tprel (map, sym_map, sym, reloc);
return;
case R_PPC64_TPREL16_LO_DS:
value = elf_machine_tprel (map, sym_map, sym, reloc);
if (dont_expect ((value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_TPREL16_LO_DS", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Half *) reloc_addr, value, 0xfffc);
break;
case R_PPC64_TPREL16_DS:
value = elf_machine_tprel (map, sym_map, sym, reloc);
if (dont_expect ((value + 0x8000) >= 0x10000 || (value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_TPREL16_DS", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Half *) reloc_addr, value, 0xfffc);
break;
case R_PPC64_TPREL16:
value = elf_machine_tprel (map, sym_map, sym, reloc);
if (dont_expect ((value + 0x8000) >= 0x10000))
_dl_reloc_overflow (map, "R_PPC64_TPREL16", reloc_addr, refsym);
*(Elf64_Half *) reloc_addr = PPC_LO (value);
break;
case R_PPC64_TPREL16_LO:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_LO (value);
break;
case R_PPC64_TPREL16_HI:
value = elf_machine_tprel (map, sym_map, sym, reloc);
if (dont_expect (value + 0x80000000 >= 0x100000000LL))
_dl_reloc_overflow (map, "R_PPC64_TPREL16_HI", reloc_addr, refsym);
*(Elf64_Half *) reloc_addr = PPC_HI (value);
break;
case R_PPC64_TPREL16_HIGH:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HI (value);
break;
case R_PPC64_TPREL16_HA:
value = elf_machine_tprel (map, sym_map, sym, reloc);
if (dont_expect (value + 0x80008000 >= 0x100000000LL))
_dl_reloc_overflow (map, "R_PPC64_TPREL16_HA", reloc_addr, refsym);
*(Elf64_Half *) reloc_addr = PPC_HA (value);
break;
case R_PPC64_TPREL16_HIGHA:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HA (value);
break;
case R_PPC64_TPREL16_HIGHER:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HIGHER (value);
break;
case R_PPC64_TPREL16_HIGHEST:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HIGHEST (value);
break;
case R_PPC64_TPREL16_HIGHERA:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HIGHERA (value);
break;
case R_PPC64_TPREL16_HIGHESTA:
value = elf_machine_tprel (map, sym_map, sym, reloc);
*(Elf64_Half *) reloc_addr = PPC_HIGHESTA (value);
break;
#ifndef RTLD_BOOTSTRAP /* None of the following appear in ld.so */
case R_PPC64_ADDR16_LO_DS:
if (dont_expect ((value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_ADDR16_LO_DS", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Half *) reloc_addr, value, 0xfffc);
break;
case R_PPC64_ADDR16_LO:
*(Elf64_Half *) reloc_addr = PPC_LO (value);
break;
case R_PPC64_ADDR16_HI:
if (dont_expect (value + 0x80000000 >= 0x100000000LL))
_dl_reloc_overflow (map, "R_PPC64_ADDR16_HI", reloc_addr, refsym);
/* Fall through. */
case R_PPC64_ADDR16_HIGH:
*(Elf64_Half *) reloc_addr = PPC_HI (value);
break;
case R_PPC64_ADDR16_HA:
if (dont_expect (value + 0x80008000 >= 0x100000000LL))
_dl_reloc_overflow (map, "R_PPC64_ADDR16_HA", reloc_addr, refsym);
/* Fall through. */
case R_PPC64_ADDR16_HIGHA:
*(Elf64_Half *) reloc_addr = PPC_HA (value);
break;
case R_PPC64_ADDR30:
{
Elf64_Addr delta = value - (Elf64_Xword) reloc_addr;
if (dont_expect ((delta + 0x80000000) >= 0x100000000LL
|| (delta & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_ADDR30", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Word *) reloc_addr, delta, 0xfffffffc);
}
break;
case R_PPC64_COPY:
if (dont_expect (sym == NULL))
/* This can happen in trace mode when an object could not be found. */
return;
if (dont_expect (sym->st_size > refsym->st_size
|| (GLRO(dl_verbose)
&& sym->st_size < refsym->st_size)))
{
const char *strtab;
strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
_dl_error_printf ("%s: Symbol `%s' has different size" \
" in shared object," \
" consider re-linking\n",
RTLD_PROGNAME, strtab + refsym->st_name);
}
memcpy (reloc_addr_arg, (char *) value,
MIN (sym->st_size, refsym->st_size));
return;
case R_PPC64_UADDR64:
((union unaligned *) reloc_addr)->u8 = value;
return;
case R_PPC64_UADDR32:
((union unaligned *) reloc_addr)->u4 = value;
return;
case R_PPC64_ADDR32:
if (dont_expect ((value + 0x80000000) >= 0x100000000LL))
_dl_reloc_overflow (map, "R_PPC64_ADDR32", reloc_addr, refsym);
*(Elf64_Word *) reloc_addr = value;
return;
case R_PPC64_ADDR24:
if (dont_expect ((value + 0x2000000) >= 0x4000000 || (value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_ADDR24", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Word *) reloc_addr, value, 0x3fffffc);
break;
case R_PPC64_ADDR16:
if (dont_expect ((value + 0x8000) >= 0x10000))
_dl_reloc_overflow (map, "R_PPC64_ADDR16", reloc_addr, refsym);
*(Elf64_Half *) reloc_addr = value;
break;
case R_PPC64_UADDR16:
if (dont_expect ((value + 0x8000) >= 0x10000))
_dl_reloc_overflow (map, "R_PPC64_UADDR16", reloc_addr, refsym);
((union unaligned *) reloc_addr)->u2 = value;
return;
case R_PPC64_ADDR16_DS:
if (dont_expect ((value + 0x8000) >= 0x10000 || (value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_ADDR16_DS", reloc_addr, refsym);
BIT_INSERT (*(Elf64_Half *) reloc_addr, value, 0xfffc);
break;
case R_PPC64_ADDR16_HIGHER:
*(Elf64_Half *) reloc_addr = PPC_HIGHER (value);
break;
case R_PPC64_ADDR16_HIGHEST:
*(Elf64_Half *) reloc_addr = PPC_HIGHEST (value);
break;
case R_PPC64_ADDR16_HIGHERA:
*(Elf64_Half *) reloc_addr = PPC_HIGHERA (value);
break;
case R_PPC64_ADDR16_HIGHESTA:
*(Elf64_Half *) reloc_addr = PPC_HIGHESTA (value);
break;
case R_PPC64_ADDR14:
case R_PPC64_ADDR14_BRTAKEN:
case R_PPC64_ADDR14_BRNTAKEN:
{
if (dont_expect ((value + 0x8000) >= 0x10000 || (value & 3) != 0))
_dl_reloc_overflow (map, "R_PPC64_ADDR14", reloc_addr, refsym);
Elf64_Word insn = *(Elf64_Word *) reloc_addr;
BIT_INSERT (insn, value, 0xfffc);
if (r_type != R_PPC64_ADDR14)
{
insn &= ~(1 << 21);
if (r_type == R_PPC64_ADDR14_BRTAKEN)
insn |= 1 << 21;
if ((insn & (0x14 << 21)) == (0x04 << 21))
insn |= 0x02 << 21;
else if ((insn & (0x14 << 21)) == (0x10 << 21))
insn |= 0x08 << 21;
}
*(Elf64_Word *) reloc_addr = insn;
}
break;
case R_PPC64_REL32:
*(Elf64_Word *) reloc_addr = value - (Elf64_Addr) reloc_addr;
return;
case R_PPC64_REL64:
*reloc_addr = value - (Elf64_Addr) reloc_addr;
return;
#endif /* !RTLD_BOOTSTRAP */
default:
_dl_reloc_bad_type (map, r_type, 0);
return;
}
MODIFIED_CODE_NOQUEUE (reloc_addr);
}
static inline void __attribute__ ((always_inline))
elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
Elf64_Addr l_addr, const Elf64_Rela *reloc,
int skip_ifunc)
{
/* elf_machine_runtime_setup handles this. */
}
#endif /* RESOLVE */
|