xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision aac28965)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_THREAD_INFO_H
3 #define __ASM_SH_THREAD_INFO_H
4 
5 /* SuperH version
6  * Copyright (C) 2002  Niibe Yutaka
7  *
8  * The copyright of original i386 version is:
9  *
10  *  Copyright (C) 2002  David Howells (dhowells@redhat.com)
11  *  - Incorporating suggestions made by Linus Torvalds and Dave Miller
12  */
13 #include <asm/page.h>
14 
15 /*
16  * Page fault error code bits
17  */
18 #define FAULT_CODE_WRITE	(1 << 0)	/* write access */
19 #define FAULT_CODE_INITIAL	(1 << 1)	/* initial page write */
20 #define FAULT_CODE_ITLB		(1 << 2)	/* ITLB miss */
21 #define FAULT_CODE_PROT		(1 << 3)	/* protection fault */
22 #define FAULT_CODE_USER		(1 << 4)	/* user-mode access */
23 
24 #ifndef __ASSEMBLY__
25 #include <asm/processor.h>
26 
27 struct thread_info {
28 	struct task_struct	*task;		/* main task structure */
29 	unsigned long		flags;		/* low level flags */
30 	__u32			status;		/* thread synchronous flags */
31 	__u32			cpu;
32 	int			preempt_count; /* 0 => preemptable, <0 => BUG */
33 	unsigned long		previous_sp;	/* sp of previous stack in case
34 						   of nested IRQ stacks */
35 	__u8			supervisor_stack[];
36 };
37 
38 #endif
39 
40 #if defined(CONFIG_4KSTACKS)
41 #define THREAD_SHIFT	12
42 #else
43 #define THREAD_SHIFT	13
44 #endif
45 
46 #define THREAD_SIZE	(1 << THREAD_SHIFT)
47 #define STACK_WARN	(THREAD_SIZE >> 3)
48 
49 /*
50  * macros/functions for gaining access to the thread information structure
51  */
52 #ifndef __ASSEMBLY__
53 #define INIT_THREAD_INFO(tsk)			\
54 {						\
55 	.task		= &tsk,			\
56 	.flags		= 0,			\
57 	.status		= 0,			\
58 	.cpu		= 0,			\
59 	.preempt_count	= INIT_PREEMPT_COUNT,	\
60 }
61 
62 /* how to get the current stack pointer from C */
63 register unsigned long current_stack_pointer asm("r15") __used;
64 
65 /* how to get the thread information struct from C */
66 static inline struct thread_info *current_thread_info(void)
67 {
68 	struct thread_info *ti;
69 #if defined(CONFIG_CPU_HAS_SR_RB)
70 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
71 #else
72 	unsigned long __dummy;
73 
74 	__asm__ __volatile__ (
75 		"mov	r15, %0\n\t"
76 		"and	%1, %0\n\t"
77 		: "=&r" (ti), "=r" (__dummy)
78 		: "1" (~(THREAD_SIZE - 1))
79 		: "memory");
80 #endif
81 
82 	return ti;
83 }
84 
85 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
86 
87 extern void arch_task_cache_init(void);
88 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
89 extern void arch_release_task_struct(struct task_struct *tsk);
90 extern void init_thread_xstate(void);
91 
92 #endif /* __ASSEMBLY__ */
93 
94 /*
95  * Thread information flags
96  *
97  * - Limited to 24 bits, upper byte used for fault code encoding.
98  *
99  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
100  *   we blow the tst immediate size constraints and need to fix up
101  *   arch/sh/kernel/entry-common.S.
102  */
103 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
104 #define TIF_SIGPENDING		1	/* signal pending */
105 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
106 #define TIF_NOTIFY_SIGNAL	3	/* signal notifications exist */
107 #define TIF_SINGLESTEP		4	/* singlestepping active */
108 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
109 #define TIF_SECCOMP		6	/* secure computing */
110 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
111 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
112 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
113 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
114 
115 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
116 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
117 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
118 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
119 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
120 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
121 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
122 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
123 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
124 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
125 
126 /* work to do in syscall trace */
127 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
128 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
129 				 _TIF_SYSCALL_TRACEPOINT)
130 
131 /* work to do on any return to u-space */
132 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
133 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
134 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
135 				 _TIF_SYSCALL_TRACEPOINT | _TIF_NOTIFY_SIGNAL)
136 
137 /* work to do on interrupt/exception return */
138 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
139 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
140 
141 /*
142  * Thread-synchronous status.
143  *
144  * This is different from the flags in that nobody else
145  * ever touches our thread-synchronous status, so we don't
146  * have to worry about atomic accesses.
147  */
148 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
149 
150 #ifndef __ASSEMBLY__
151 
152 #define TI_FLAG_FAULT_CODE_SHIFT	24
153 
154 /*
155  * Additional thread flag encoding
156  */
157 static inline void set_thread_fault_code(unsigned int val)
158 {
159 	struct thread_info *ti = current_thread_info();
160 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
161 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
162 }
163 
164 static inline unsigned int get_thread_fault_code(void)
165 {
166 	struct thread_info *ti = current_thread_info();
167 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
168 }
169 
170 #endif	/* !__ASSEMBLY__ */
171 #endif /* __ASM_SH_THREAD_INFO_H */
172