xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision 034f90b3)
1 #ifndef __ASM_SH_THREAD_INFO_H
2 #define __ASM_SH_THREAD_INFO_H
3 
4 /* SuperH version
5  * Copyright (C) 2002  Niibe Yutaka
6  *
7  * The copyright of original i386 version is:
8  *
9  *  Copyright (C) 2002  David Howells (dhowells@redhat.com)
10  *  - Incorporating suggestions made by Linus Torvalds and Dave Miller
11  */
12 #ifdef __KERNEL__
13 
14 #include <asm/page.h>
15 
16 /*
17  * Page fault error code bits
18  */
19 #define FAULT_CODE_WRITE	(1 << 0)	/* write access */
20 #define FAULT_CODE_INITIAL	(1 << 1)	/* initial page write */
21 #define FAULT_CODE_ITLB		(1 << 2)	/* ITLB miss */
22 #define FAULT_CODE_PROT		(1 << 3)	/* protection fault */
23 #define FAULT_CODE_USER		(1 << 4)	/* user-mode access */
24 
25 #ifndef __ASSEMBLY__
26 #include <asm/processor.h>
27 
28 struct thread_info {
29 	struct task_struct	*task;		/* main task structure */
30 	struct exec_domain	*exec_domain;	/* execution domain */
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 	.exec_domain	= &default_exec_domain,	\
60 	.flags		= 0,			\
61 	.status		= 0,			\
62 	.cpu		= 0,			\
63 	.preempt_count	= INIT_PREEMPT_COUNT,	\
64 	.addr_limit	= KERNEL_DS,		\
65 }
66 
67 #define init_thread_info	(init_thread_union.thread_info)
68 #define init_stack		(init_thread_union.stack)
69 
70 /* how to get the current stack pointer from C */
71 register unsigned long current_stack_pointer asm("r15") __used;
72 
73 /* how to get the thread information struct from C */
74 static inline struct thread_info *current_thread_info(void)
75 {
76 	struct thread_info *ti;
77 #if defined(CONFIG_SUPERH64)
78 	__asm__ __volatile__ ("getcon	cr17, %0" : "=r" (ti));
79 #elif defined(CONFIG_CPU_HAS_SR_RB)
80 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
81 #else
82 	unsigned long __dummy;
83 
84 	__asm__ __volatile__ (
85 		"mov	r15, %0\n\t"
86 		"and	%1, %0\n\t"
87 		: "=&r" (ti), "=r" (__dummy)
88 		: "1" (~(THREAD_SIZE - 1))
89 		: "memory");
90 #endif
91 
92 	return ti;
93 }
94 
95 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
96 
97 extern void arch_task_cache_init(void);
98 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
99 extern void arch_release_task_struct(struct task_struct *tsk);
100 extern void init_thread_xstate(void);
101 
102 #endif /* __ASSEMBLY__ */
103 
104 /*
105  * Thread information flags
106  *
107  * - Limited to 24 bits, upper byte used for fault code encoding.
108  *
109  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
110  *   we blow the tst immediate size constraints and need to fix up
111  *   arch/sh/kernel/entry-common.S.
112  */
113 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
114 #define TIF_SIGPENDING		1	/* signal pending */
115 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
116 #define TIF_SINGLESTEP		4	/* singlestepping active */
117 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
118 #define TIF_SECCOMP		6	/* secure computing */
119 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
120 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
121 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
122 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
123 
124 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
125 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
126 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
127 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
128 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
129 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
130 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
131 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
132 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
133 
134 /* work to do in syscall trace */
135 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
136 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
137 				 _TIF_SYSCALL_TRACEPOINT)
138 
139 /* work to do on any return to u-space */
140 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
141 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
142 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
143 				 _TIF_SYSCALL_TRACEPOINT)
144 
145 /* work to do on interrupt/exception return */
146 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
147 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
148 
149 /*
150  * Thread-synchronous status.
151  *
152  * This is different from the flags in that nobody else
153  * ever touches our thread-synchronous status, so we don't
154  * have to worry about atomic accesses.
155  */
156 #define TS_RESTORE_SIGMASK	0x0001	/* restore signal mask in do_signal() */
157 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
158 
159 #ifndef __ASSEMBLY__
160 
161 #define HAVE_SET_RESTORE_SIGMASK	1
162 static inline void set_restore_sigmask(void)
163 {
164 	struct thread_info *ti = current_thread_info();
165 	ti->status |= TS_RESTORE_SIGMASK;
166 	WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
167 }
168 
169 #define TI_FLAG_FAULT_CODE_SHIFT	24
170 
171 /*
172  * Additional thread flag encoding
173  */
174 static inline void set_thread_fault_code(unsigned int val)
175 {
176 	struct thread_info *ti = current_thread_info();
177 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
178 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
179 }
180 
181 static inline unsigned int get_thread_fault_code(void)
182 {
183 	struct thread_info *ti = current_thread_info();
184 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
185 }
186 
187 static inline void clear_restore_sigmask(void)
188 {
189 	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
190 }
191 static inline bool test_restore_sigmask(void)
192 {
193 	return current_thread_info()->status & TS_RESTORE_SIGMASK;
194 }
195 static inline bool test_and_clear_restore_sigmask(void)
196 {
197 	struct thread_info *ti = current_thread_info();
198 	if (!(ti->status & TS_RESTORE_SIGMASK))
199 		return false;
200 	ti->status &= ~TS_RESTORE_SIGMASK;
201 	return true;
202 }
203 
204 #endif	/* !__ASSEMBLY__ */
205 
206 #endif /* __KERNEL__ */
207 
208 #endif /* __ASM_SH_THREAD_INFO_H */
209