1/* Thread-local storage descriptor handling in the ELF dynamic linker.
2 x86_64 version.
3 Copyright (C) 2005-2022 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20#include <stdint.h>
21
22#ifndef _X86_64_DL_TLSDESC_H
23# define _X86_64_DL_TLSDESC_H 1
24
25/* Type used to represent a TLS descriptor in the GOT. */
26struct tlsdesc
27{
28 /* Anonymous union is used here to ensure that GOT entry slot is always
29 8 bytes for both x32 and x86-64. */
30 union
31 {
32 ptrdiff_t (*entry) (struct tlsdesc *on_rax);
33 uint64_t entry_slot;
34 };
35 union
36 {
37 void *arg;
38 uint64_t arg_slot;
39 };
40};
41
42typedef struct dl_tls_index
43{
44 uint64_t ti_module;
45 uint64_t ti_offset;
46} tls_index;
47
48/* Type used as the argument in a TLS descriptor for a symbol that
49 needs dynamic TLS offsets. */
50struct tlsdesc_dynamic_arg
51{
52 tls_index tlsinfo;
53 size_t gen_count;
54};
55
56extern ptrdiff_t attribute_hidden
57 _dl_tlsdesc_return(struct tlsdesc *on_rax),
58 _dl_tlsdesc_undefweak(struct tlsdesc *on_rax);
59
60# ifdef SHARED
61extern void *_dl_make_tlsdesc_dynamic (struct link_map *map,
62 size_t ti_offset)
63 attribute_hidden;
64
65extern ptrdiff_t attribute_hidden _dl_tlsdesc_dynamic(struct tlsdesc *);
66# endif
67
68#endif
69

source code of glibc/sysdeps/x86_64/dl-tlsdesc.h