1/*
2 * thread_info.h: sparc low-level thread information
3 * adapted from the ppc version by Pete Zaitcev, which was
4 * adapted from the i386 version by Paul Mackerras
5 *
6 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
7 * Copyright (c) 2002  Pete Zaitcev (zaitcev@yahoo.com)
8 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
9 */
10
11#ifndef _ASM_THREAD_INFO_H
12#define _ASM_THREAD_INFO_H
13
14#ifdef __KERNEL__
15
16#ifndef __ASSEMBLY__
17
18#include <asm/btfixup.h>
19#include <asm/ptrace.h>
20#include <asm/page.h>
21
22/*
23 * Low level task data.
24 *
25 * If you change this, change the TI_* offsets below to match.
26 */
27#define NSWINS 8
28struct thread_info {
29	unsigned long		uwinmask;
30	struct task_struct	*task;		/* main task structure */
31	struct exec_domain	*exec_domain;	/* execution domain */
32	unsigned long		flags;		/* low level flags */
33	int			cpu;		/* cpu we're on */
34	int			preempt_count;	/* 0 => preemptable,
35						   <0 => BUG */
36	int			softirq_count;
37	int			hardirq_count;
38
39	/* Context switch saved kernel state. */
40	unsigned long ksp;	/* ... ksp __attribute__ ((aligned (8))); */
41	unsigned long kpc;
42	unsigned long kpsr;
43	unsigned long kwim;
44
45	/* A place to store user windows and stack pointers
46	 * when the stack needs inspection.
47	 */
48	struct reg_window	reg_window[NSWINS];	/* align for ldd! */
49	unsigned long		rwbuf_stkptrs[NSWINS];
50	unsigned long		w_saved;
51
52	struct restart_block	restart_block;
53};
54
55/*
56 * macros/functions for gaining access to the thread information structure
57 *
58 * preempt_count needs to be 1 initially, until the scheduler is functional.
59 */
60#define INIT_THREAD_INFO(tsk)				\
61{							\
62	.uwinmask	=	0,			\
63	.task		=	&tsk,			\
64	.exec_domain	=	&default_exec_domain,	\
65	.flags		=	0,			\
66	.cpu		=	0,			\
67	.preempt_count	=	1,			\
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 thread information struct from C */
77register struct thread_info *current_thread_info_reg asm("g6");
78#define current_thread_info()   (current_thread_info_reg)
79
80/*
81 * thread information allocation
82 */
83#if PAGE_SHIFT == 13
84#define THREAD_INFO_ORDER  0
85#else /* PAGE_SHIFT */
86#define THREAD_INFO_ORDER  1
87#endif
88
89BTFIXUPDEF_CALL(struct thread_info *, alloc_thread_info, void)
90#define alloc_thread_info(tsk) BTFIXUP_CALL(alloc_thread_info)()
91
92BTFIXUPDEF_CALL(void, free_thread_info, struct thread_info *)
93#define free_thread_info(ti) BTFIXUP_CALL(free_thread_info)(ti)
94
95#endif /* __ASSEMBLY__ */
96
97/*
98 * Size of kernel stack for each process.
99 * Observe the order of get_free_pages() in alloc_thread_info().
100 * The sun4 has 8K stack too, because it's short on memory, and 16K is a waste.
101 */
102#define THREAD_SIZE		8192
103
104/*
105 * Offsets in thread_info structure, used in assembly code
106 * The "#define REGWIN_SZ 0x40" was abolished, so no multiplications.
107 */
108#define TI_UWINMASK	0x00	/* uwinmask */
109#define TI_TASK		0x04
110#define TI_EXECDOMAIN	0x08	/* exec_domain */
111#define TI_FLAGS	0x0c
112#define TI_CPU		0x10
113#define TI_PREEMPT	0x14	/* preempt_count */
114#define TI_SOFTIRQ	0x18	/* softirq_count */
115#define TI_HARDIRQ	0x1c	/* hardirq_count */
116#define TI_KSP		0x20	/* ksp */
117#define TI_KPC		0x24	/* kpc (ldd'ed with kpc) */
118#define TI_KPSR		0x28	/* kpsr */
119#define TI_KWIM		0x2c	/* kwim (ldd'ed with kpsr) */
120#define TI_REG_WINDOW	0x30
121#define TI_RWIN_SPTRS	0x230
122#define TI_W_SAVED	0x250
123/* #define TI_RESTART_BLOCK 0x25n */ /* Nobody cares */
124
125#define PREEMPT_ACTIVE		0x4000000
126
127/*
128 * thread information flag bit numbers
129 */
130#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
131/* flag bit 1 is available */
132#define TIF_SIGPENDING		2	/* signal pending */
133#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
134#define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
135#define TIF_USEDFPU		8	/* FPU was used by this task
136					 * this quantum (SMP) */
137#define TIF_POLLING_NRFLAG	9	/* true if poll_idle() is polling
138					 * TIF_NEED_RESCHED */
139#define TIF_MEMDIE		10
140
141/* as above, but as bit values */
142#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
143#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
144#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
145#define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
146#define _TIF_USEDFPU		(1<<TIF_USEDFPU)
147#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
148
149#endif /* __KERNEL__ */
150
151#endif /* _ASM_THREAD_INFO_H */
152