xref: /freebsd/lib/libc/i386/static_tls.h (revision 5d00c5a6571cdf533228338fa7ca532c91af1d66)
1*5d00c5a6SKonstantin Belousov /*-
2*5d00c5a6SKonstantin Belousov  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3*5d00c5a6SKonstantin Belousov  *
4*5d00c5a6SKonstantin Belousov  * Copyright (c) 2019 The FreeBSD Foundation
5*5d00c5a6SKonstantin Belousov  *
6*5d00c5a6SKonstantin Belousov  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
7*5d00c5a6SKonstantin Belousov  * under sponsorship from the FreeBSD Foundation.
8*5d00c5a6SKonstantin Belousov  *
9*5d00c5a6SKonstantin Belousov  * Redistribution and use in source and binary forms, with or without
10*5d00c5a6SKonstantin Belousov  * modification, are permitted provided that the following conditions
11*5d00c5a6SKonstantin Belousov  * are met:
12*5d00c5a6SKonstantin Belousov  * 1. Redistributions of source code must retain the above copyright
13*5d00c5a6SKonstantin Belousov  *    notice, this list of conditions and the following disclaimer.
14*5d00c5a6SKonstantin Belousov  * 2. Redistributions in binary form must reproduce the above copyright
15*5d00c5a6SKonstantin Belousov  *    notice, this list of conditions and the following disclaimer in the
16*5d00c5a6SKonstantin Belousov  *    documentation and/or other materials provided with the distribution.
17*5d00c5a6SKonstantin Belousov  *
18*5d00c5a6SKonstantin Belousov  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19*5d00c5a6SKonstantin Belousov  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20*5d00c5a6SKonstantin Belousov  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21*5d00c5a6SKonstantin Belousov  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22*5d00c5a6SKonstantin Belousov  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23*5d00c5a6SKonstantin Belousov  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24*5d00c5a6SKonstantin Belousov  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25*5d00c5a6SKonstantin Belousov  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26*5d00c5a6SKonstantin Belousov  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27*5d00c5a6SKonstantin Belousov  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28*5d00c5a6SKonstantin Belousov  * SUCH DAMAGE.
29*5d00c5a6SKonstantin Belousov  *
30*5d00c5a6SKonstantin Belousov  * $FreeBSD$
31*5d00c5a6SKonstantin Belousov  */
32*5d00c5a6SKonstantin Belousov 
33*5d00c5a6SKonstantin Belousov #ifndef _LIBC_I386_STATIC_TLS_H
34*5d00c5a6SKonstantin Belousov #define _LIBC_I386_STATIC_TLS_H
35*5d00c5a6SKonstantin Belousov 
36*5d00c5a6SKonstantin Belousov static __inline uintptr_t
37*5d00c5a6SKonstantin Belousov _libc_get_static_tls_base(size_t offset)
38*5d00c5a6SKonstantin Belousov {
39*5d00c5a6SKonstantin Belousov 	uintptr_t tlsbase;
40*5d00c5a6SKonstantin Belousov 
41*5d00c5a6SKonstantin Belousov 	__asm __volatile("movl %%gs:0, %0" : "=r" (tlsbase));
42*5d00c5a6SKonstantin Belousov 	tlsbase -= offset;
43*5d00c5a6SKonstantin Belousov 	return (tlsbase);
44*5d00c5a6SKonstantin Belousov }
45*5d00c5a6SKonstantin Belousov 
46*5d00c5a6SKonstantin Belousov #endif
47