1/* $OpenBSD: tcb.h,v 1.7 2017/04/20 10:03:40 kettenis Exp $ */
2
3/*
4 * Copyright (c) 2011 Philip Guenther <guenther@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#ifndef _MACHINE_TCB_H_
20#define _MACHINE_TCB_H_
21
22#ifdef _KERNEL
23
24#include <machine/reg.h>
25
26/*
27 * In userspace, register %g7 contains the address of the thread's TCB
28 */
29#define TCB_GET(p) \
30 ((void *)(p)->p_md.md_tf->tf_global[7])
31#define TCB_SET(p, addr) \
32 ((p)->p_md.md_tf->tf_global[7] = (int64_t)(addr))
33
34#else /* _KERNEL */
35
36/* ELF TLS ABI calls for big TCB, with static TLS data at negative offsets */
37#define TLS_VARIANT 2
38
39register void *__tcb __asm__ ("g7");
40#define TCB_GET() (__tcb)
41#define TCB_SET(tcb) ((__tcb) = (tcb))
42
43#endif /* _KERNEL */
44#endif /* _MACHINE_TCB_H_ */