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 #ifdef CONFIG_ARM64_4K_PAGES
27 #define THREAD_SIZE_ORDER	2
28 #elif defined(CONFIG_ARM64_16K_PAGES)
29 #define THREAD_SIZE_ORDER	0
30 #endif
31 
32 #define THREAD_SIZE		16384
33 #define THREAD_START_SP		(THREAD_SIZE - 16)
34 
35 #ifndef __ASSEMBLY__
36 
37 struct task_struct;
38 
39 #include <asm/types.h>
40 
41 typedef unsigned long mm_segment_t;
42 
43 /*
44  * low level task data that entry.S needs immediate access to.
45  * __switch_to() assumes cpu_context follows immediately after cpu_domain.
46  */
47 struct thread_info {
48 	unsigned long		flags;		/* low level flags */
49 	mm_segment_t		addr_limit;	/* address limit */
50 	struct task_struct	*task;		/* main task structure */
51 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
52 	int			cpu;		/* cpu */
53 };
54 
55 #define INIT_THREAD_INFO(tsk)						\
56 {									\
57 	.task		= &tsk,						\
58 	.flags		= 0,						\
59 	.preempt_count	= INIT_PREEMPT_COUNT,				\
60 	.addr_limit	= KERNEL_DS,					\
61 }
62 
63 #define init_thread_info	(init_thread_union.thread_info)
64 #define init_stack		(init_thread_union.stack)
65 
66 /*
67  * how to get the current stack pointer from C
68  */
69 register unsigned long current_stack_pointer asm ("sp");
70 
71 /*
72  * how to get the thread information struct from C
73  */
74 static inline struct thread_info *current_thread_info(void) __attribute_const__;
75 
76 /*
77  * struct thread_info can be accessed directly via sp_el0.
78  */
79 static inline struct thread_info *current_thread_info(void)
80 {
81 	unsigned long sp_el0;
82 
83 	asm ("mrs %0, sp_el0" : "=r" (sp_el0));
84 
85 	return (struct thread_info *)sp_el0;
86 }
87 
88 #define thread_saved_pc(tsk)	\
89 	((unsigned long)(tsk->thread.cpu_context.pc))
90 #define thread_saved_sp(tsk)	\
91 	((unsigned long)(tsk->thread.cpu_context.sp))
92 #define thread_saved_fp(tsk)	\
93 	((unsigned long)(tsk->thread.cpu_context.fp))
94 
95 #endif
96 
97 /*
98  * thread information flags:
99  *  TIF_SYSCALL_TRACE	- syscall trace active
100  *  TIF_SYSCALL_TRACEPOINT - syscall tracepoint for ftrace
101  *  TIF_SYSCALL_AUDIT	- syscall auditing
102  *  TIF_SECOMP		- syscall secure computing
103  *  TIF_SIGPENDING	- signal pending
104  *  TIF_NEED_RESCHED	- rescheduling necessary
105  *  TIF_NOTIFY_RESUME	- callback before returning to user
106  *  TIF_USEDFPU		- FPU was used by this task this quantum (SMP)
107  */
108 #define TIF_SIGPENDING		0
109 #define TIF_NEED_RESCHED	1
110 #define TIF_NOTIFY_RESUME	2	/* callback before returning to user */
111 #define TIF_FOREIGN_FPSTATE	3	/* CPU's FP state is not current's */
112 #define TIF_NOHZ		7
113 #define TIF_SYSCALL_TRACE	8
114 #define TIF_SYSCALL_AUDIT	9
115 #define TIF_SYSCALL_TRACEPOINT	10
116 #define TIF_SECCOMP		11
117 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
118 #define TIF_FREEZE		19
119 #define TIF_RESTORE_SIGMASK	20
120 #define TIF_SINGLESTEP		21
121 #define TIF_32BIT		22	/* 32bit process */
122 
123 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
124 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
125 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
126 #define _TIF_FOREIGN_FPSTATE	(1 << TIF_FOREIGN_FPSTATE)
127 #define _TIF_NOHZ		(1 << TIF_NOHZ)
128 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
129 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
130 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
131 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
132 #define _TIF_32BIT		(1 << TIF_32BIT)
133 
134 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
135 				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
136 
137 #define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
138 				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
139 				 _TIF_NOHZ)
140 
141 #endif /* __KERNEL__ */
142 #endif /* __ASM_THREAD_INFO_H */
143