1/*
2 * Based on arch/arm/include/asm/thread_info.h
3 *
4 * Copyright (C) 2002 Russell King.
5 * Copyright (C) 2012 ARM Ltd.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program 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
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18 */
19#ifndef __ASM_THREAD_INFO_H
20#define __ASM_THREAD_INFO_H
21
22#ifdef __KERNEL__
23
24#include <linux/compiler.h>
25
26#ifndef CONFIG_ARM64_64K_PAGES
27#define THREAD_SIZE_ORDER	2
28#endif
29
30#define THREAD_SIZE		16384
31#define THREAD_START_SP		(THREAD_SIZE - 16)
32
33#ifndef __ASSEMBLY__
34
35struct task_struct;
36
37#include <asm/types.h>
38
39typedef unsigned long mm_segment_t;
40
41/*
42 * low level task data that entry.S needs immediate access to.
43 * __switch_to() assumes cpu_context follows immediately after cpu_domain.
44 */
45struct thread_info {
46	unsigned long		flags;		/* low level flags */
47	mm_segment_t		addr_limit;	/* address limit */
48	struct task_struct	*task;		/* main task structure */
49	int			preempt_count;	/* 0 => preemptable, <0 => bug */
50	int			cpu;		/* cpu */
51};
52
53#define INIT_THREAD_INFO(tsk)						\
54{									\
55	.task		= &tsk,						\
56	.flags		= 0,						\
57	.preempt_count	= INIT_PREEMPT_COUNT,				\
58	.addr_limit	= KERNEL_DS,					\
59}
60
61#define init_thread_info	(init_thread_union.thread_info)
62#define init_stack		(init_thread_union.stack)
63
64/*
65 * how to get the current stack pointer from C
66 */
67register unsigned long current_stack_pointer asm ("sp");
68
69/*
70 * how to get the thread information struct from C
71 */
72static inline struct thread_info *current_thread_info(void) __attribute_const__;
73
74static inline struct thread_info *current_thread_info(void)
75{
76	return (struct thread_info *)
77		(current_stack_pointer & ~(THREAD_SIZE - 1));
78}
79
80#define thread_saved_pc(tsk)	\
81	((unsigned long)(tsk->thread.cpu_context.pc))
82#define thread_saved_sp(tsk)	\
83	((unsigned long)(tsk->thread.cpu_context.sp))
84#define thread_saved_fp(tsk)	\
85	((unsigned long)(tsk->thread.cpu_context.fp))
86
87#endif
88
89/*
90 * thread information flags:
91 *  TIF_SYSCALL_TRACE	- syscall trace active
92 *  TIF_SYSCALL_TRACEPOINT - syscall tracepoint for ftrace
93 *  TIF_SYSCALL_AUDIT	- syscall auditing
94 *  TIF_SECOMP		- syscall secure computing
95 *  TIF_SIGPENDING	- signal pending
96 *  TIF_NEED_RESCHED	- rescheduling necessary
97 *  TIF_NOTIFY_RESUME	- callback before returning to user
98 *  TIF_USEDFPU		- FPU was used by this task this quantum (SMP)
99 */
100#define TIF_SIGPENDING		0
101#define TIF_NEED_RESCHED	1
102#define TIF_NOTIFY_RESUME	2	/* callback before returning to user */
103#define TIF_FOREIGN_FPSTATE	3	/* CPU's FP state is not current's */
104#define TIF_NOHZ		7
105#define TIF_SYSCALL_TRACE	8
106#define TIF_SYSCALL_AUDIT	9
107#define TIF_SYSCALL_TRACEPOINT	10
108#define TIF_SECCOMP		11
109#define TIF_MEMDIE		18	/* is terminating due to OOM killer */
110#define TIF_FREEZE		19
111#define TIF_RESTORE_SIGMASK	20
112#define TIF_SINGLESTEP		21
113#define TIF_32BIT		22	/* 32bit process */
114#define TIF_SWITCH_MM		23	/* deferred switch_mm */
115
116#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
117#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
118#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
119#define _TIF_FOREIGN_FPSTATE	(1 << TIF_FOREIGN_FPSTATE)
120#define _TIF_NOHZ		(1 << TIF_NOHZ)
121#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
122#define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
123#define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
124#define _TIF_SECCOMP		(1 << TIF_SECCOMP)
125#define _TIF_32BIT		(1 << TIF_32BIT)
126
127#define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
128				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
129
130#define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
131				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
132				 _TIF_NOHZ)
133
134#endif /* __KERNEL__ */
135#endif /* __ASM_THREAD_INFO_H */
136