1#ifndef _ASM_M32R_THREAD_INFO_H
2#define _ASM_M32R_THREAD_INFO_H
3
4/* thread_info.h: m32r low-level thread information
5 *
6 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
7 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
8 * Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
9 */
10
11#ifdef __KERNEL__
12
13#ifndef __ASSEMBLY__
14#include <asm/processor.h>
15#endif
16
17/*
18 * low level task data that entry.S needs immediate access to
19 * - this struct should fit entirely inside of one cache line
20 * - this struct shares the supervisor stack pages
21 * - if the contents of this structure are changed, the assembly constants must also be changed
22 */
23#ifndef __ASSEMBLY__
24
25struct thread_info {
26	struct task_struct	*task;		/* main task structure */
27	struct exec_domain	*exec_domain;	/* execution domain */
28	unsigned long		flags;		/* low level flags */
29	unsigned long		status;		/* thread-synchronous flags */
30	__u32			cpu;		/* current CPU */
31	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
32
33	mm_segment_t		addr_limit;	/* thread address space:
34					 	   0-0xBFFFFFFF for user-thread
35						   0-0xFFFFFFFF for kernel-thread
36						*/
37	struct restart_block    restart_block;
38
39	__u8			supervisor_stack[0];
40};
41
42#else /* !__ASSEMBLY__ */
43
44/* offsets into the thread_info struct for assembly code access */
45#define TI_TASK		0x00000000
46#define TI_EXEC_DOMAIN	0x00000004
47#define TI_FLAGS	0x00000008
48#define TI_STATUS	0x0000000C
49#define TI_CPU		0x00000010
50#define TI_PRE_COUNT	0x00000014
51#define TI_ADDR_LIMIT	0x00000018
52#define TI_RESTART_BLOCK 0x000001C
53
54#endif
55
56#define PREEMPT_ACTIVE		0x10000000
57
58/*
59 * macros/functions for gaining access to the thread information structure
60 *
61 * preempt_count needs to be 1 initially, until the scheduler is functional.
62 */
63#ifndef __ASSEMBLY__
64
65#define INIT_THREAD_INFO(tsk)			\
66{						\
67	.task		= &tsk,			\
68	.exec_domain	= &default_exec_domain,	\
69	.flags		= 0,			\
70	.cpu		= 0,			\
71	.preempt_count	= 1,			\
72	.addr_limit	= KERNEL_DS,		\
73	.restart_block = {			\
74		.fn = do_no_restart_syscall,	\
75	},					\
76}
77
78#define init_thread_info	(init_thread_union.thread_info)
79#define init_stack		(init_thread_union.stack)
80
81#define THREAD_SIZE (2*PAGE_SIZE)
82
83/* how to get the thread information struct from C */
84static inline struct thread_info *current_thread_info(void)
85{
86	struct thread_info *ti;
87
88	__asm__ __volatile__ (
89		"ldi	%0, #%1			\n\t"
90		"and	%0, sp			\n\t"
91		: "=r" (ti) : "i" (~(THREAD_SIZE - 1))
92	);
93
94	return ti;
95}
96
97/* thread information allocation */
98#ifdef CONFIG_DEBUG_STACK_USAGE
99#define alloc_thread_info(tsk)					\
100	({							\
101		struct thread_info *ret;			\
102	 							\
103	 	ret = kmalloc(THREAD_SIZE, GFP_KERNEL);		\
104	 	if (ret)					\
105	 		memset(ret, 0, THREAD_SIZE);		\
106	 	ret;						\
107	 })
108#else
109#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
110#endif
111
112#define free_thread_info(info) kfree(info)
113
114#define TI_FLAG_FAULT_CODE_SHIFT	28
115
116static inline void set_thread_fault_code(unsigned int val)
117{
118	struct thread_info *ti = current_thread_info();
119	ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
120		| (val << TI_FLAG_FAULT_CODE_SHIFT);
121}
122
123static inline unsigned int get_thread_fault_code(void)
124{
125	struct thread_info *ti = current_thread_info();
126	return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
127}
128
129#else /* !__ASSEMBLY__ */
130
131#define THREAD_SIZE	8192
132
133/* how to get the thread information struct from ASM */
134#define GET_THREAD_INFO(reg)	GET_THREAD_INFO reg
135	.macro GET_THREAD_INFO reg
136	ldi	\reg, #-THREAD_SIZE
137	and	\reg, sp
138	.endm
139
140#endif
141
142/*
143 * thread information flags
144 * - these are process state flags that various assembly files may need to access
145 * - pending work-to-be-done flags are in LSW
146 * - other flags in MSW
147 */
148#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
149#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
150#define TIF_SIGPENDING		2	/* signal pending */
151#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
152#define TIF_SINGLESTEP		4	/* restore singlestep on return to user mode */
153#define TIF_IRET		5	/* return with iret */
154#define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
155					/* 31..28 fault code */
156#define TIF_MEMDIE		17
157
158#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
159#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
160#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
161#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
162#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
163#define _TIF_IRET		(1<<TIF_IRET)
164#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
165
166#define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
167#define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
168
169/*
170 * Thread-synchronous status.
171 *
172 * This is different from the flags in that nobody else
173 * ever touches our thread-synchronous status, so we don't
174 * have to worry about atomic accesses.
175 */
176#define TS_USEDFPU		0x0001	/* FPU was used by this task this quantum (SMP) */
177
178#endif /* __KERNEL__ */
179
180#endif /* _ASM_M32R_THREAD_INFO_H */
181