1/*
2 *  include/asm-s390/thread_info.h
3 *
4 *  S390 version
5 *    Copyright (C) IBM Corp. 2002,2006
6 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
7 */
8
9#ifndef _ASM_THREAD_INFO_H
10#define _ASM_THREAD_INFO_H
11
12#ifdef __KERNEL__
13
14/*
15 * Size of kernel stack for each process
16 */
17#ifndef __s390x__
18#ifndef __SMALL_STACK
19#define THREAD_ORDER 1
20#define ASYNC_ORDER  1
21#else
22#define THREAD_ORDER 0
23#define ASYNC_ORDER  0
24#endif
25#else /* __s390x__ */
26#ifndef __SMALL_STACK
27#define THREAD_ORDER 2
28#define ASYNC_ORDER  2
29#else
30#define THREAD_ORDER 1
31#define ASYNC_ORDER  1
32#endif
33#endif /* __s390x__ */
34
35#define THREAD_SIZE (PAGE_SIZE << THREAD_ORDER)
36#define ASYNC_SIZE  (PAGE_SIZE << ASYNC_ORDER)
37
38#ifndef __ASSEMBLY__
39#include <asm/processor.h>
40#include <asm/lowcore.h>
41
42/*
43 * low level task data that entry.S needs immediate access to
44 * - this struct should fit entirely inside of one cache line
45 * - this struct shares the supervisor stack pages
46 * - if the contents of this structure are changed, the assembly constants must also be changed
47 */
48struct thread_info {
49	struct task_struct	*task;		/* main task structure */
50	struct exec_domain	*exec_domain;	/* execution domain */
51	unsigned long		flags;		/* low level flags */
52	unsigned int		cpu;		/* current CPU */
53	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
54	struct restart_block	restart_block;
55};
56
57/*
58 * macros/functions for gaining access to the thread information structure
59 */
60#define INIT_THREAD_INFO(tsk)			\
61{						\
62	.task		= &tsk,			\
63	.exec_domain	= &default_exec_domain,	\
64	.flags		= 0,			\
65	.cpu		= 0,			\
66	.preempt_count	= 1,			\
67	.restart_block	= {			\
68		.fn = do_no_restart_syscall,	\
69	},					\
70}
71
72#define init_thread_info	(init_thread_union.thread_info)
73#define init_stack		(init_thread_union.stack)
74
75/* how to get the thread information struct from C */
76static inline struct thread_info *current_thread_info(void)
77{
78	return (struct thread_info *)((*(unsigned long *) __LC_KERNEL_STACK)-THREAD_SIZE);
79}
80
81/* thread information allocation */
82#define alloc_thread_info(tsk) ((struct thread_info *) \
83	__get_free_pages(GFP_KERNEL,THREAD_ORDER))
84#define free_thread_info(ti) free_pages((unsigned long) (ti),THREAD_ORDER)
85
86#endif
87
88/*
89 * thread information flags bit numbers
90 */
91#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
92#define TIF_RESTORE_SIGMASK	1	/* restore signal mask in do_signal() */
93#define TIF_SIGPENDING		2	/* signal pending */
94#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
95#define TIF_RESTART_SVC		4	/* restart svc with new svc number */
96#define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
97#define TIF_SINGLE_STEP		6	/* deliver sigtrap on return to user */
98#define TIF_MCCK_PENDING	7	/* machine check handling is pending */
99#define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
100#define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling
101					   TIF_NEED_RESCHED */
102#define TIF_31BIT		18	/* 32bit process */
103#define TIF_MEMDIE		19
104
105#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
106#define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
107#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
108#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
109#define _TIF_RESTART_SVC	(1<<TIF_RESTART_SVC)
110#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
111#define _TIF_SINGLE_STEP	(1<<TIF_SINGLE_STEP)
112#define _TIF_MCCK_PENDING	(1<<TIF_MCCK_PENDING)
113#define _TIF_USEDFPU		(1<<TIF_USEDFPU)
114#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
115#define _TIF_31BIT		(1<<TIF_31BIT)
116
117#endif /* __KERNEL__ */
118
119#define PREEMPT_ACTIVE		0x4000000
120
121#endif /* _ASM_THREAD_INFO_H */
122