xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision feac8c8b)
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 #ifdef __KERNEL__
14 
15 #include <asm/page.h>
16 
17 /*
18  * Page fault error code bits
19  */
20 #define FAULT_CODE_WRITE	(1 << 0)	/* write access */
21 #define FAULT_CODE_INITIAL	(1 << 1)	/* initial page write */
22 #define FAULT_CODE_ITLB		(1 << 2)	/* ITLB miss */
23 #define FAULT_CODE_PROT		(1 << 3)	/* protection fault */
24 #define FAULT_CODE_USER		(1 << 4)	/* user-mode access */
25 
26 #ifndef __ASSEMBLY__
27 #include <asm/processor.h>
28 
29 struct thread_info {
30 	struct task_struct	*task;		/* main task structure */
31 	unsigned long		flags;		/* low level flags */
32 	__u32			status;		/* thread synchronous flags */
33 	__u32			cpu;
34 	int			preempt_count; /* 0 => preemptable, <0 => BUG */
35 	mm_segment_t		addr_limit;	/* thread address space */
36 	unsigned long		previous_sp;	/* sp of previous stack in case
37 						   of nested IRQ stacks */
38 	__u8			supervisor_stack[0];
39 };
40 
41 #endif
42 
43 #if defined(CONFIG_4KSTACKS)
44 #define THREAD_SHIFT	12
45 #else
46 #define THREAD_SHIFT	13
47 #endif
48 
49 #define THREAD_SIZE	(1 << THREAD_SHIFT)
50 #define STACK_WARN	(THREAD_SIZE >> 3)
51 
52 /*
53  * macros/functions for gaining access to the thread information structure
54  */
55 #ifndef __ASSEMBLY__
56 #define INIT_THREAD_INFO(tsk)			\
57 {						\
58 	.task		= &tsk,			\
59 	.flags		= 0,			\
60 	.status		= 0,			\
61 	.cpu		= 0,			\
62 	.preempt_count	= INIT_PREEMPT_COUNT,	\
63 	.addr_limit	= KERNEL_DS,		\
64 }
65 
66 /* how to get the current stack pointer from C */
67 register unsigned long current_stack_pointer asm("r15") __used;
68 
69 /* how to get the thread information struct from C */
70 static inline struct thread_info *current_thread_info(void)
71 {
72 	struct thread_info *ti;
73 #if defined(CONFIG_SUPERH64)
74 	__asm__ __volatile__ ("getcon	cr17, %0" : "=r" (ti));
75 #elif defined(CONFIG_CPU_HAS_SR_RB)
76 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
77 #else
78 	unsigned long __dummy;
79 
80 	__asm__ __volatile__ (
81 		"mov	r15, %0\n\t"
82 		"and	%1, %0\n\t"
83 		: "=&r" (ti), "=r" (__dummy)
84 		: "1" (~(THREAD_SIZE - 1))
85 		: "memory");
86 #endif
87 
88 	return ti;
89 }
90 
91 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
92 
93 extern void arch_task_cache_init(void);
94 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
95 extern void arch_release_task_struct(struct task_struct *tsk);
96 extern void init_thread_xstate(void);
97 
98 #endif /* __ASSEMBLY__ */
99 
100 /*
101  * Thread information flags
102  *
103  * - Limited to 24 bits, upper byte used for fault code encoding.
104  *
105  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
106  *   we blow the tst immediate size constraints and need to fix up
107  *   arch/sh/kernel/entry-common.S.
108  */
109 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
110 #define TIF_SIGPENDING		1	/* signal pending */
111 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
112 #define TIF_SINGLESTEP		4	/* singlestepping active */
113 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
114 #define TIF_SECCOMP		6	/* secure computing */
115 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
116 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
117 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
118 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
119 
120 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
121 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
122 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
123 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
124 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
125 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
126 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
127 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
128 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
129 
130 /* work to do in syscall trace */
131 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
132 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
133 				 _TIF_SYSCALL_TRACEPOINT)
134 
135 /* work to do on any return to u-space */
136 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
137 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
138 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
139 				 _TIF_SYSCALL_TRACEPOINT)
140 
141 /* work to do on interrupt/exception return */
142 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
143 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
144 
145 /*
146  * Thread-synchronous status.
147  *
148  * This is different from the flags in that nobody else
149  * ever touches our thread-synchronous status, so we don't
150  * have to worry about atomic accesses.
151  */
152 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
153 
154 #ifndef __ASSEMBLY__
155 
156 #define TI_FLAG_FAULT_CODE_SHIFT	24
157 
158 /*
159  * Additional thread flag encoding
160  */
161 static inline void set_thread_fault_code(unsigned int val)
162 {
163 	struct thread_info *ti = current_thread_info();
164 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
165 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
166 }
167 
168 static inline unsigned int get_thread_fault_code(void)
169 {
170 	struct thread_info *ti = current_thread_info();
171 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
172 }
173 
174 #endif	/* !__ASSEMBLY__ */
175 
176 #endif /* __KERNEL__ */
177 
178 #endif /* __ASM_SH_THREAD_INFO_H */
179