1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 *
5 * Vineetg: Oct 2009
6 *  No need for ARC specific thread_info allocator (kmalloc/free). This is
7 *  anyways one page allocation, thus slab alloc can be short-circuited and
8 *  the generic version (get_free_page) would be loads better.
9 *
10 * Sameer Dhavale: Codito Technologies 2004
11 */
12
13#ifndef _ASM_THREAD_INFO_H
14#define _ASM_THREAD_INFO_H
15
16#include <asm/page.h>
17
18#ifdef CONFIG_16KSTACKS
19#define THREAD_SIZE_ORDER 1
20#else
21#define THREAD_SIZE_ORDER 0
22#endif
23
24#define THREAD_SIZE     (PAGE_SIZE << THREAD_SIZE_ORDER)
25#define THREAD_SHIFT	(PAGE_SHIFT << THREAD_SIZE_ORDER)
26
27#ifndef __ASSEMBLY__
28
29#include <linux/thread_info.h>
30#include <asm/segment.h>
31
32/*
33 * low level task data that entry.S needs immediate access to
34 * - this struct should fit entirely inside of one cache line
35 * - this struct shares the supervisor stack pages
36 * - if the contents of this structure are changed, the assembly constants
37 *   must also be changed
38 */
39struct thread_info {
40	unsigned long flags;		/* low level flags */
41	int preempt_count;		/* 0 => preemptable, <0 => BUG */
42	struct task_struct *task;	/* main task structure */
43	mm_segment_t addr_limit;	/* thread address space */
44	__u32 cpu;			/* current CPU */
45	unsigned long thr_ptr;		/* TLS ptr */
46};
47
48/*
49 * macros/functions for gaining access to the thread information structure
50 *
51 * preempt_count needs to be 1 initially, until the scheduler is functional.
52 */
53#define INIT_THREAD_INFO(tsk)			\
54{						\
55	.task       = &tsk,			\
56	.flags      = 0,			\
57	.cpu        = 0,			\
58	.preempt_count  = INIT_PREEMPT_COUNT,	\
59	.addr_limit = KERNEL_DS,		\
60}
61
62static inline __attribute_const__ struct thread_info *current_thread_info(void)
63{
64	register unsigned long sp asm("sp");
65	return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
66}
67
68#endif /* !__ASSEMBLY__ */
69
70/*
71 * thread information flags
72 * - these are process state flags that various assembly files may need to
73 *   access
74 * - pending work-to-be-done flags are in LSW
75 * - other flags in MSW
76 */
77#define TIF_RESTORE_SIGMASK	0	/* restore sig mask in do_signal() */
78#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
79#define TIF_SIGPENDING		2	/* signal pending */
80#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
81#define TIF_SYSCALL_AUDIT	4	/* syscall auditing active */
82#define TIF_NOTIFY_SIGNAL	5	/* signal notifications exist */
83#define TIF_SYSCALL_TRACE	15	/* syscall trace active */
84
85/* true if poll_idle() is polling TIF_NEED_RESCHED */
86#define TIF_MEMDIE		16
87
88#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
89#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
90#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
91#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
92#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
93#define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
94#define _TIF_MEMDIE		(1<<TIF_MEMDIE)
95
96/* work to do on interrupt/exception return */
97#define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
98				 _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL)
99
100/*
101 * _TIF_ALLWORK_MASK includes SYSCALL_TRACE, but we don't need it.
102 * SYSCALL_TRACE is anyway seperately/unconditionally tested right after a
103 * syscall, so all that reamins to be tested is _TIF_WORK_MASK
104 */
105
106#endif /* _ASM_THREAD_INFO_H */
107