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 
35 struct task_struct;
36 
37 #include <asm/types.h>
38 
39 typedef 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  */
45 struct 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  */
67 register unsigned long current_stack_pointer asm ("sp");
68 
69 /*
70  * how to get the thread information struct from C
71  */
72 static inline struct thread_info *current_thread_info(void) __attribute_const__;
73 
74 static 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