xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision 3cf3cdea)
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 	mm_segment_t		addr_limit;	/* thread address space */
34 	unsigned long		previous_sp;	/* sp of previous stack in case
35 						   of nested IRQ stacks */
36 	__u8			supervisor_stack[0];
37 };
38 
39 #endif
40 
41 #if defined(CONFIG_4KSTACKS)
42 #define THREAD_SHIFT	12
43 #else
44 #define THREAD_SHIFT	13
45 #endif
46 
47 #define THREAD_SIZE	(1 << THREAD_SHIFT)
48 #define STACK_WARN	(THREAD_SIZE >> 3)
49 
50 /*
51  * macros/functions for gaining access to the thread information structure
52  */
53 #ifndef __ASSEMBLY__
54 #define INIT_THREAD_INFO(tsk)			\
55 {						\
56 	.task		= &tsk,			\
57 	.flags		= 0,			\
58 	.status		= 0,			\
59 	.cpu		= 0,			\
60 	.preempt_count	= INIT_PREEMPT_COUNT,	\
61 	.addr_limit	= KERNEL_DS,		\
62 }
63 
64 /* how to get the current stack pointer from C */
65 register unsigned long current_stack_pointer asm("r15") __used;
66 
67 /* how to get the thread information struct from C */
68 static inline struct thread_info *current_thread_info(void)
69 {
70 	struct thread_info *ti;
71 #if defined(CONFIG_CPU_HAS_SR_RB)
72 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
73 #else
74 	unsigned long __dummy;
75 
76 	__asm__ __volatile__ (
77 		"mov	r15, %0\n\t"
78 		"and	%1, %0\n\t"
79 		: "=&r" (ti), "=r" (__dummy)
80 		: "1" (~(THREAD_SIZE - 1))
81 		: "memory");
82 #endif
83 
84 	return ti;
85 }
86 
87 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
88 
89 extern void arch_task_cache_init(void);
90 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
91 extern void arch_release_task_struct(struct task_struct *tsk);
92 extern void init_thread_xstate(void);
93 
94 #endif /* __ASSEMBLY__ */
95 
96 /*
97  * Thread information flags
98  *
99  * - Limited to 24 bits, upper byte used for fault code encoding.
100  *
101  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
102  *   we blow the tst immediate size constraints and need to fix up
103  *   arch/sh/kernel/entry-common.S.
104  */
105 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
106 #define TIF_SIGPENDING		1	/* signal pending */
107 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
108 #define TIF_NOTIFY_SIGNAL	3	/* signal notifications exist */
109 #define TIF_SINGLESTEP		4	/* singlestepping active */
110 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
111 #define TIF_SECCOMP		6	/* secure computing */
112 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
113 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
114 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
115 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
116 
117 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
118 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
119 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
120 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
121 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
122 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
123 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
124 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
125 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
126 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
127 
128 /* work to do in syscall trace */
129 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
130 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
131 				 _TIF_SYSCALL_TRACEPOINT)
132 
133 /* work to do on any return to u-space */
134 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
135 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
136 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
137 				 _TIF_SYSCALL_TRACEPOINT | _TIF_NOTIFY_SIGNAL)
138 
139 /* work to do on interrupt/exception return */
140 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
141 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
142 
143 /*
144  * Thread-synchronous status.
145  *
146  * This is different from the flags in that nobody else
147  * ever touches our thread-synchronous status, so we don't
148  * have to worry about atomic accesses.
149  */
150 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
151 
152 #ifndef __ASSEMBLY__
153 
154 #define TI_FLAG_FAULT_CODE_SHIFT	24
155 
156 /*
157  * Additional thread flag encoding
158  */
159 static inline void set_thread_fault_code(unsigned int val)
160 {
161 	struct thread_info *ti = current_thread_info();
162 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
163 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
164 }
165 
166 static inline unsigned int get_thread_fault_code(void)
167 {
168 	struct thread_info *ti = current_thread_info();
169 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
170 }
171 
172 #endif	/* !__ASSEMBLY__ */
173 #endif /* __ASM_SH_THREAD_INFO_H */
174