xref: /openbmc/linux/arch/sh/include/asm/thread_info.h (revision 95e9fd10)
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 #define PREEMPT_ACTIVE		0x10000000
45 
46 #if defined(CONFIG_4KSTACKS)
47 #define THREAD_SHIFT	12
48 #else
49 #define THREAD_SHIFT	13
50 #endif
51 
52 #define THREAD_SIZE	(1 << THREAD_SHIFT)
53 #define STACK_WARN	(THREAD_SIZE >> 3)
54 
55 /*
56  * macros/functions for gaining access to the thread information structure
57  */
58 #ifndef __ASSEMBLY__
59 #define INIT_THREAD_INFO(tsk)			\
60 {						\
61 	.task		= &tsk,			\
62 	.exec_domain	= &default_exec_domain,	\
63 	.flags		= 0,			\
64 	.status		= 0,			\
65 	.cpu		= 0,			\
66 	.preempt_count	= INIT_PREEMPT_COUNT,	\
67 	.addr_limit	= KERNEL_DS,		\
68 	.restart_block	= {			\
69 		.fn = do_no_restart_syscall,	\
70 	},					\
71 }
72 
73 #define init_thread_info	(init_thread_union.thread_info)
74 #define init_stack		(init_thread_union.stack)
75 
76 /* how to get the current stack pointer from C */
77 register unsigned long current_stack_pointer asm("r15") __used;
78 
79 /* how to get the thread information struct from C */
80 static inline struct thread_info *current_thread_info(void)
81 {
82 	struct thread_info *ti;
83 #if defined(CONFIG_SUPERH64)
84 	__asm__ __volatile__ ("getcon	cr17, %0" : "=r" (ti));
85 #elif defined(CONFIG_CPU_HAS_SR_RB)
86 	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
87 #else
88 	unsigned long __dummy;
89 
90 	__asm__ __volatile__ (
91 		"mov	r15, %0\n\t"
92 		"and	%1, %0\n\t"
93 		: "=&r" (ti), "=r" (__dummy)
94 		: "1" (~(THREAD_SIZE - 1))
95 		: "memory");
96 #endif
97 
98 	return ti;
99 }
100 
101 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
102 
103 extern void arch_task_cache_init(void);
104 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
105 extern void arch_release_task_struct(struct task_struct *tsk);
106 extern void init_thread_xstate(void);
107 
108 #endif /* __ASSEMBLY__ */
109 
110 /*
111  * Thread information flags
112  *
113  * - Limited to 24 bits, upper byte used for fault code encoding.
114  *
115  * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
116  *   we blow the tst immediate size constraints and need to fix up
117  *   arch/sh/kernel/entry-common.S.
118  */
119 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
120 #define TIF_SIGPENDING		1	/* signal pending */
121 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
122 #define TIF_SINGLESTEP		4	/* singlestepping active */
123 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
124 #define TIF_SECCOMP		6	/* secure computing */
125 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
126 #define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
127 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
128 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
129 
130 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
131 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
132 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
133 #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
134 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
135 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
136 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
137 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
138 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
139 
140 /* work to do in syscall trace */
141 #define _TIF_WORK_SYSCALL_MASK	(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
142 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
143 				 _TIF_SYSCALL_TRACEPOINT)
144 
145 /* work to do on any return to u-space */
146 #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
147 				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
148 				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
149 				 _TIF_SYSCALL_TRACEPOINT)
150 
151 /* work to do on interrupt/exception return */
152 #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
153 				 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
154 
155 /*
156  * Thread-synchronous status.
157  *
158  * This is different from the flags in that nobody else
159  * ever touches our thread-synchronous status, so we don't
160  * have to worry about atomic accesses.
161  */
162 #define TS_RESTORE_SIGMASK	0x0001	/* restore signal mask in do_signal() */
163 #define TS_USEDFPU		0x0002	/* FPU used by this task this quantum */
164 
165 #ifndef __ASSEMBLY__
166 
167 #define HAVE_SET_RESTORE_SIGMASK	1
168 static inline void set_restore_sigmask(void)
169 {
170 	struct thread_info *ti = current_thread_info();
171 	ti->status |= TS_RESTORE_SIGMASK;
172 	WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
173 }
174 
175 #define TI_FLAG_FAULT_CODE_SHIFT	24
176 
177 /*
178  * Additional thread flag encoding
179  */
180 static inline void set_thread_fault_code(unsigned int val)
181 {
182 	struct thread_info *ti = current_thread_info();
183 	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
184 		| (val << TI_FLAG_FAULT_CODE_SHIFT);
185 }
186 
187 static inline unsigned int get_thread_fault_code(void)
188 {
189 	struct thread_info *ti = current_thread_info();
190 	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
191 }
192 
193 static inline void clear_restore_sigmask(void)
194 {
195 	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
196 }
197 static inline bool test_restore_sigmask(void)
198 {
199 	return current_thread_info()->status & TS_RESTORE_SIGMASK;
200 }
201 static inline bool test_and_clear_restore_sigmask(void)
202 {
203 	struct thread_info *ti = current_thread_info();
204 	if (!(ti->status & TS_RESTORE_SIGMASK))
205 		return false;
206 	ti->status &= ~TS_RESTORE_SIGMASK;
207 	return true;
208 }
209 #endif	/* !__ASSEMBLY__ */
210 
211 #endif /* __KERNEL__ */
212 
213 #endif /* __ASM_SH_THREAD_INFO_H */
214