xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision 62e7ca52)
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 	struct restart_block	restart_block;
37 	unsigned long		previous_sp;	/* sp of previous stack in case
38 						   of nested IRQ stacks */
39 	__u8			supervisor_stack[0];
40 };
41 
42 #endif
43 
44 #if defined(CONFIG_4KSTACKS)
45 #define THREAD_SHIFT	12
46 #else
47 #define THREAD_SHIFT	13
48 #endif
49 
50 #define THREAD_SIZE	(1 << THREAD_SHIFT)
51 #define STACK_WARN	(THREAD_SIZE >> 3)
52 
53 /*
54  * macros/functions for gaining access to the thread information structure
55  */
56 #ifndef __ASSEMBLY__
57 #define INIT_THREAD_INFO(tsk)			\
58 {						\
59 	.task		= &tsk,			\
60 	.exec_domain	= &default_exec_domain,	\
61 	.flags		= 0,			\
62 	.status		= 0,			\
63 	.cpu		= 0,			\
64 	.preempt_count	= INIT_PREEMPT_COUNT,	\
65 	.addr_limit	= KERNEL_DS,		\
66 	.restart_block	= {			\
67 		.fn = do_no_restart_syscall,	\
68 	},					\
69 }
70 
71 #define init_thread_info	(init_thread_union.thread_info)
72 #define init_stack		(init_thread_union.stack)
73 
74 /* how to get the current stack pointer from C */
75 register unsigned long current_stack_pointer asm("r15") __used;
76 
77 /* how to get the thread information struct from C */
78 static inline struct thread_info *current_thread_info(void)
79 {
80 	struct thread_info *ti;
81 #if defined(CONFIG_SUPERH64)
82 	__asm__ __volatile__ ("getcon	cr17, %0" : "=r" (ti));
83 #elif defined(CONFIG_CPU_HAS_SR_RB)
84 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
85 #else
86 	unsigned long __dummy;
87 
88 	__asm__ __volatile__ (
89 		"mov	r15, %0\n\t"
90 		"and	%1, %0\n\t"
91 		: "=&r" (ti), "=r" (__dummy)
92 		: "1" (~(THREAD_SIZE - 1))
93 		: "memory");
94 #endif
95 
96 	return ti;
97 }
98 
99 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
100 
101 extern void arch_task_cache_init(void);
102 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
103 extern void arch_release_task_struct(struct task_struct *tsk);
104 extern void init_thread_xstate(void);
105 
106 #endif /* __ASSEMBLY__ */
107 
108 /*
109  * Thread information flags
110  *
111  * - Limited to 24 bits, upper byte used for fault code encoding.
112  *
113  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
114  *   we blow the tst immediate size constraints and need to fix up
115  *   arch/sh/kernel/entry-common.S.
116  */
117 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
118 #define TIF_SIGPENDING		1	/* signal pending */
119 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
120 #define TIF_SINGLESTEP		4	/* singlestepping active */
121 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
122 #define TIF_SECCOMP		6	/* secure computing */
123 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
124 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
125 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
126 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
127 
128 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
129 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
130 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
131 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
132 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
133 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
134 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
135 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
136 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
137 
138 /* work to do in syscall trace */
139 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
140 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
141 				 _TIF_SYSCALL_TRACEPOINT)
142 
143 /* work to do on any return to u-space */
144 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
145 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
146 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
147 				 _TIF_SYSCALL_TRACEPOINT)
148 
149 /* work to do on interrupt/exception return */
150 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
151 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
152 
153 /*
154  * Thread-synchronous status.
155  *
156  * This is different from the flags in that nobody else
157  * ever touches our thread-synchronous status, so we don't
158  * have to worry about atomic accesses.
159  */
160 #define TS_RESTORE_SIGMASK	0x0001	/* restore signal mask in do_signal() */
161 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
162 
163 #ifndef __ASSEMBLY__
164 
165 #define HAVE_SET_RESTORE_SIGMASK	1
166 static inline void set_restore_sigmask(void)
167 {
168 	struct thread_info *ti = current_thread_info();
169 	ti->status |= TS_RESTORE_SIGMASK;
170 	WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
171 }
172 
173 #define TI_FLAG_FAULT_CODE_SHIFT	24
174 
175 /*
176  * Additional thread flag encoding
177  */
178 static inline void set_thread_fault_code(unsigned int val)
179 {
180 	struct thread_info *ti = current_thread_info();
181 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
182 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
183 }
184 
185 static inline unsigned int get_thread_fault_code(void)
186 {
187 	struct thread_info *ti = current_thread_info();
188 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
189 }
190 
191 static inline void clear_restore_sigmask(void)
192 {
193 	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
194 }
195 static inline bool test_restore_sigmask(void)
196 {
197 	return current_thread_info()->status & TS_RESTORE_SIGMASK;
198 }
199 static inline bool test_and_clear_restore_sigmask(void)
200 {
201 	struct thread_info *ti = current_thread_info();
202 	if (!(ti->status & TS_RESTORE_SIGMASK))
203 		return false;
204 	ti->status &= ~TS_RESTORE_SIGMASK;
205 	return true;
206 }
207 
208 #endif	/* !__ASSEMBLY__ */
209 
210 #endif /* __KERNEL__ */
211 
212 #endif /* __ASM_SH_THREAD_INFO_H */
213