1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (C) 2003 David Xu <davidxu@freebsd.org>
5 * Copyright (c) 2001 Daniel Eischen <deischen@freebsd.org>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Neither the name of the author nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #ifndef _MACHINE_TLS_H_
31 #define _MACHINE_TLS_H_
32
33 #include <x86/sysarch.h>
34
35 #define TLS_VARIANT_II
36
37 struct pthread;
38
39 /*
40 * Variant II tcb, first two members are required by rtld,
41 * %fs (amd64) / %gs (i386) points to the structure.
42 */
43 struct tcb {
44 struct tcb *tcb_self; /* required by rtld */
45 uintptr_t *tcb_dtv; /* required by rtld */
46 struct pthread *tcb_thread;
47 };
48
49 #define TLS_DTV_OFFSET 0
50 #ifdef __amd64__
51 #define TLS_TCB_ALIGN 16
52 #else
53 #define TLS_TCB_ALIGN 4
54 #endif
55 #define TLS_TCB_SIZE sizeof(struct tcb)
56 #define TLS_TP_OFFSET 0
57
58 static __inline void
_tcb_set(struct tcb * tcb)59 _tcb_set(struct tcb *tcb)
60 {
61 #ifdef __amd64__
62 amd64_set_fsbase(tcb);
63 #else
64 i386_set_gsbase(tcb);
65 #endif
66 }
67
68 static __inline struct tcb *
_tcb_get(void)69 _tcb_get(void)
70 {
71 struct tcb *tcb;
72
73 #ifdef __amd64__
74 __asm __volatile("movq %%fs:0, %0" : "=r" (tcb));
75 #else
76 __asm __volatile("movl %%gs:0, %0" : "=r" (tcb));
77 #endif
78 return (tcb);
79 }
80
81 #endif /* !_MACHINE_TLS_H_ */
82