1/* thread_info.h: MIPS low-level thread information
2 *
3 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
4 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
5 */
6
7#ifndef _ASM_THREAD_INFO_H
8#define _ASM_THREAD_INFO_H
9
10#ifdef __KERNEL__
11
12
13#ifndef __ASSEMBLY__
14
15#include <asm/processor.h>
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
22 *   must also be changed
23 */
24struct thread_info {
25	struct task_struct	*task;		/* main task structure */
26	struct exec_domain	*exec_domain;	/* execution domain */
27	unsigned long		flags;		/* low level flags */
28	unsigned long		tp_value;	/* thread pointer */
29	__u32			cpu;		/* current CPU */
30	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
31
32	mm_segment_t		addr_limit;	/* thread address space:
33						   0-0xBFFFFFFF for user-thead
34						   0-0xFFFFFFFF for kernel-thread
35						*/
36	struct restart_block	restart_block;
37	struct pt_regs		*regs;
38};
39
40/*
41 * macros/functions for gaining access to the thread information structure
42 *
43 * preempt_count needs to be 1 initially, until the scheduler is functional.
44 */
45#define INIT_THREAD_INFO(tsk)			\
46{						\
47	.task		= &tsk,			\
48	.exec_domain	= &default_exec_domain,	\
49	.flags		= 0,			\
50	.cpu		= 0,			\
51	.preempt_count	= 1,			\
52	.addr_limit	= KERNEL_DS,		\
53	.restart_block	= {			\
54		.fn = do_no_restart_syscall,	\
55	},					\
56}
57
58#define init_thread_info	(init_thread_union.thread_info)
59#define init_stack		(init_thread_union.stack)
60
61/* How to get the thread information struct from C.  */
62register struct thread_info *__current_thread_info __asm__("$28");
63#define current_thread_info()  __current_thread_info
64
65/* thread information allocation */
66#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
67#if defined(CONFIG_BCM_ENDPOINTDRV)
68#define THREAD_SIZE_ORDER (2)
69#else
70#define THREAD_SIZE_ORDER (1)
71#endif
72#endif
73#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT)
74#define THREAD_SIZE_ORDER (2)
75#endif
76#ifdef CONFIG_PAGE_SIZE_8KB
77#define THREAD_SIZE_ORDER (1)
78#endif
79#ifdef CONFIG_PAGE_SIZE_16KB
80#define THREAD_SIZE_ORDER (0)
81#endif
82#ifdef CONFIG_PAGE_SIZE_64KB
83#define THREAD_SIZE_ORDER (0)
84#endif
85
86#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
87#define THREAD_MASK (THREAD_SIZE - 1UL)
88
89#ifdef CONFIG_DEBUG_STACK_USAGE
90#define alloc_thread_info(tsk)					\
91({								\
92	struct thread_info *ret;				\
93								\
94	ret = kmalloc(THREAD_SIZE, GFP_KERNEL);			\
95	if (ret)						\
96		memset(ret, 0, THREAD_SIZE);			\
97	ret;							\
98})
99#else
100#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
101#endif
102
103#define free_thread_info(info) kfree(info)
104
105#endif /* !__ASSEMBLY__ */
106
107#define PREEMPT_ACTIVE		0x10000000
108
109/*
110 * thread information flags
111 * - these are process state flags that various assembly files may need to
112 *   access
113 * - pending work-to-be-done flags are in LSW
114 * - other flags in MSW
115 */
116#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
117#define TIF_SIGPENDING		2	/* signal pending */
118#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
119#define TIF_SYSCALL_AUDIT	4	/* syscall auditing active */
120#define TIF_SECCOMP		5	/* secure computing */
121#define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
122#define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
123#define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
124#define TIF_MEMDIE		18
125#define TIF_FREEZE		19
126#define TIF_SYSCALL_TRACE	31	/* syscall trace active */
127
128#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
129#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
130#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
131#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
132#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
133#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
134#define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
135#define _TIF_USEDFPU		(1<<TIF_USEDFPU)
136#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
137#define _TIF_FREEZE		(1<<TIF_FREEZE)
138
139/* work to do on interrupt/exception return */
140#define _TIF_WORK_MASK		(0x0000ffef & ~_TIF_SECCOMP)
141/* work to do on any return to u-space */
142#define _TIF_ALLWORK_MASK	(0x8000ffff & ~_TIF_SECCOMP)
143
144#endif /* __KERNEL__ */
145
146#endif /* _ASM_THREAD_INFO_H */
147