xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision 9cfc5c90)
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 	unsigned long		flags;		/* low level flags */
31 	__u32			status;		/* thread synchronous flags */
32 	__u32			cpu;
33 	int			preempt_count; /* 0 => preemptable, <0 => BUG */
34 	mm_segment_t		addr_limit;	/* thread address space */
35 	unsigned long		previous_sp;	/* sp of previous stack in case
36 						   of nested IRQ stacks */
37 	__u8			supervisor_stack[0];
38 };
39 
40 #endif
41 
42 #if defined(CONFIG_4KSTACKS)
43 #define THREAD_SHIFT	12
44 #else
45 #define THREAD_SHIFT	13
46 #endif
47 
48 #define THREAD_SIZE	(1 << THREAD_SHIFT)
49 #define STACK_WARN	(THREAD_SIZE >> 3)
50 
51 /*
52  * macros/functions for gaining access to the thread information structure
53  */
54 #ifndef __ASSEMBLY__
55 #define INIT_THREAD_INFO(tsk)			\
56 {						\
57 	.task		= &tsk,			\
58 	.flags		= 0,			\
59 	.status		= 0,			\
60 	.cpu		= 0,			\
61 	.preempt_count	= INIT_PREEMPT_COUNT,	\
62 	.addr_limit	= KERNEL_DS,		\
63 }
64 
65 #define init_thread_info	(init_thread_union.thread_info)
66 #define init_stack		(init_thread_union.stack)
67 
68 /* how to get the current stack pointer from C */
69 register unsigned long current_stack_pointer asm("r15") __used;
70 
71 /* how to get the thread information struct from C */
72 static inline struct thread_info *current_thread_info(void)
73 {
74 	struct thread_info *ti;
75 #if defined(CONFIG_SUPERH64)
76 	__asm__ __volatile__ ("getcon	cr17, %0" : "=r" (ti));
77 #elif defined(CONFIG_CPU_HAS_SR_RB)
78 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
79 #else
80 	unsigned long __dummy;
81 
82 	__asm__ __volatile__ (
83 		"mov	r15, %0\n\t"
84 		"and	%1, %0\n\t"
85 		: "=&r" (ti), "=r" (__dummy)
86 		: "1" (~(THREAD_SIZE - 1))
87 		: "memory");
88 #endif
89 
90 	return ti;
91 }
92 
93 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
94 
95 extern void arch_task_cache_init(void);
96 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
97 extern void arch_release_task_struct(struct task_struct *tsk);
98 extern void init_thread_xstate(void);
99 
100 #endif /* __ASSEMBLY__ */
101 
102 /*
103  * Thread information flags
104  *
105  * - Limited to 24 bits, upper byte used for fault code encoding.
106  *
107  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
108  *   we blow the tst immediate size constraints and need to fix up
109  *   arch/sh/kernel/entry-common.S.
110  */
111 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
112 #define TIF_SIGPENDING		1	/* signal pending */
113 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
114 #define TIF_SINGLESTEP		4	/* singlestepping active */
115 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
116 #define TIF_SECCOMP		6	/* secure computing */
117 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
118 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
119 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
120 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
121 
122 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
123 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
124 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
125 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
126 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
127 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
128 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
129 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
130 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
131 
132 /* work to do in syscall trace */
133 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
134 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
135 				 _TIF_SYSCALL_TRACEPOINT)
136 
137 /* work to do on any return to u-space */
138 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
139 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
140 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
141 				 _TIF_SYSCALL_TRACEPOINT)
142 
143 /* work to do on interrupt/exception return */
144 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
145 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
146 
147 /*
148  * Thread-synchronous status.
149  *
150  * This is different from the flags in that nobody else
151  * ever touches our thread-synchronous status, so we don't
152  * have to worry about atomic accesses.
153  */
154 #define TS_RESTORE_SIGMASK	0x0001	/* restore signal mask in do_signal() */
155 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
156 
157 #ifndef __ASSEMBLY__
158 
159 #define HAVE_SET_RESTORE_SIGMASK	1
160 static inline void set_restore_sigmask(void)
161 {
162 	struct thread_info *ti = current_thread_info();
163 	ti->status |= TS_RESTORE_SIGMASK;
164 	WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
165 }
166 
167 #define TI_FLAG_FAULT_CODE_SHIFT	24
168 
169 /*
170  * Additional thread flag encoding
171  */
172 static inline void set_thread_fault_code(unsigned int val)
173 {
174 	struct thread_info *ti = current_thread_info();
175 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
176 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
177 }
178 
179 static inline unsigned int get_thread_fault_code(void)
180 {
181 	struct thread_info *ti = current_thread_info();
182 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
183 }
184 
185 static inline void clear_restore_sigmask(void)
186 {
187 	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
188 }
189 static inline bool test_restore_sigmask(void)
190 {
191 	return current_thread_info()->status & TS_RESTORE_SIGMASK;
192 }
193 static inline bool test_and_clear_restore_sigmask(void)
194 {
195 	struct thread_info *ti = current_thread_info();
196 	if (!(ti->status & TS_RESTORE_SIGMASK))
197 		return false;
198 	ti->status &= ~TS_RESTORE_SIGMASK;
199 	return true;
200 }
201 
202 #endif	/* !__ASSEMBLY__ */
203 
204 #endif /* __KERNEL__ */
205 
206 #endif /* __ASM_SH_THREAD_INFO_H */
207