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
28 struct 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 */
77 register 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 #define THREAD_INFO_ORDER  1
84 
85 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
86 
87 BTFIXUPDEF_CALL(struct thread_info *, alloc_thread_info, void)
88 #define alloc_thread_info(tsk) BTFIXUP_CALL(alloc_thread_info)()
89 
90 BTFIXUPDEF_CALL(void, free_thread_info, struct thread_info *)
91 #define free_thread_info(ti) BTFIXUP_CALL(free_thread_info)(ti)
92 
93 #endif /* __ASSEMBLY__ */
94 
95 /*
96  * Size of kernel stack for each process.
97  * Observe the order of get_free_pages() in alloc_thread_info().
98  * The sun4 has 8K stack too, because it's short on memory, and 16K is a waste.
99  */
100 #define THREAD_SIZE		8192
101 
102 /*
103  * Offsets in thread_info structure, used in assembly code
104  * The "#define REGWIN_SZ 0x40" was abolished, so no multiplications.
105  */
106 #define TI_UWINMASK	0x00	/* uwinmask */
107 #define TI_TASK		0x04
108 #define TI_EXECDOMAIN	0x08	/* exec_domain */
109 #define TI_FLAGS	0x0c
110 #define TI_CPU		0x10
111 #define TI_PREEMPT	0x14	/* preempt_count */
112 #define TI_SOFTIRQ	0x18	/* softirq_count */
113 #define TI_HARDIRQ	0x1c	/* hardirq_count */
114 #define TI_KSP		0x20	/* ksp */
115 #define TI_KPC		0x24	/* kpc (ldd'ed with kpc) */
116 #define TI_KPSR		0x28	/* kpsr */
117 #define TI_KWIM		0x2c	/* kwim (ldd'ed with kpsr) */
118 #define TI_REG_WINDOW	0x30
119 #define TI_RWIN_SPTRS	0x230
120 #define TI_W_SAVED	0x250
121 /* #define TI_RESTART_BLOCK 0x25n */ /* Nobody cares */
122 
123 #define PREEMPT_ACTIVE		0x4000000
124 
125 /*
126  * thread information flag bit numbers
127  */
128 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
129 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
130 #define TIF_SIGPENDING		2	/* signal pending */
131 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
132 #define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
133 #define TIF_USEDFPU		8	/* FPU was used by this task
134 					 * this quantum (SMP) */
135 #define TIF_POLLING_NRFLAG	9	/* true if poll_idle() is polling
136 					 * TIF_NEED_RESCHED */
137 #define TIF_MEMDIE		10
138 #define TIF_FREEZE		11	/* is freezing for suspend */
139 
140 /* as above, but as bit values */
141 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
142 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
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 #define _TIF_DO_NOTIFY_RESUME_MASK	(_TIF_NOTIFY_RESUME | \
150 					 _TIF_SIGPENDING | \
151 					 _TIF_RESTORE_SIGMASK)
152 #define _TIF_FREEZE		(1<<TIF_FREEZE)
153 
154 #endif /* __KERNEL__ */
155 
156 #endif /* _ASM_THREAD_INFO_H */
157